Patent application number | Description | Published |
20080206993 | Using Spectra to Determine Polishing Endpoints - Methods of determining a polishing endpoint are described using spectra obtained during a polishing sequence. In particular, techniques for using only desired spectra, faster searching methods and more robust rate determination methods are described. | 08-28-2008 |
20080239308 | HIGH THROUGHPUT MEASUREMENT SYSTEM - A substrate processing system includes a processing module to process a substrate, a factory interface module configured to accommodate at least one cassette for holding the substrate, a spectrographic monitoring system positioned in or adjoining the factory interface module, and a substrate handler to transfer the substrate between the at least one cassette, the spectrographic monitoring system and the processing module. | 10-02-2008 |
20080243433 | METHODS AND APPARATUS FOR GENERATING A LIBRARY OF SPECTRA - A method of generating a library from a reference substrate for use in processing product wafers is described. The method includes measuring substrate characteristics at a plurality of well-defined points of a reference substrate, measuring spectra at plurality of measurement points of the reference substrate, there being more measurement points than well-defined points, and associating measured spectra with measured substrate characteristics. | 10-02-2008 |
20080305729 | THIN POLISHING PAD WITH WINDOW AND MOLDING PROCESS - A polishing pad is described that has a polishing layer with a polishing surface, an adhesive layer on a side of the polishing layer opposite the polishing layer, and a solid light-transmitting window extending through and molded to the polishing layer. The window has a top surface coplanar with the polishing surface and a bottom surface coplanar with a lower surface of the adhesive layer. A method of making a polishing pad includes forming an aperture through a polishing layer and an adhesive layer, securing a backing piece to the adhesive layer on a side opposite a polishing surface of the polishing layer, dispensing a liquid polymer into the aperture, and curing the liquid polymer to form a window. | 12-11-2008 |
20090017726 | SPECTRA BASED ENDPOINTING FOR CHEMICAL MECHANICAL POLISHING - Methods and apparatus for spectrum-based endpointing. An endpointing method includes selecting two or more reference spectra. Each reference spectrum is a spectrum of white light reflected from a film of interest on a first substrate and has a thickness greater than a target thickness. The reference spectra is selected for particular spectra-based endpoint determination logic so that the target thickness is achieved when endpoint is called by applying the particular spectra-based endpoint logic. The method includes obtaining two or more current spectra. Each current spectrum is a spectrum of white light reflected from a film of interest on a second substrate when the film of interest is being subjected to a polishing step and has a current thickness that is greater than the target thickness. The method includes determining, for the second substrate, when an endpoint of the polishing step has been achieved. | 01-15-2009 |
20090033942 | Determining Physical Property of Substrate - A method of determining a physical property of a substrate includes recording a first spectrum obtained from a substrate, the first spectrum being obtained during a polishing process that alters a physical property of the substrate. The method includes identifying, in a database, at least one of several previously recorded spectra that is similar to the recorded first spectrum. Each of the spectra in the database has a physical property value associated therewith. The method includes generating a signal indicating that a first value of the physical property is associated with the first spectrum, the first value being determined using the physical property value associated with the identified previously recorded spectrum in the database. A system for determining a physical property of a substrate includes a polishing machine, an endpoint determining module, and a database. | 02-05-2009 |
20090036026 | SUBSTRATE THICKNESS MEASURING DURING POLISHING - A computer program product that determines a polishing endpoint includes obtaining spectra from different zones on a substrate during different times in a polishing sequence, matches the spectra with indexes in a library and uses the indexes to determining a polishing rate for each of the different zones from the indexes. An adjusted polishing rate can be determined for one of the zones, which causes the substrate to have a desired profile when the polishing end time is reached. | 02-05-2009 |
20090149115 | WAFER EDGE CHARACTERIZATION BY SUCCESSIVE RADIUS MEASUREMENTS - Systems and methods for performing one or more measurements of a substrate at one or more radii along the substrate are described. Thickness measurements taken at various radii along the substrate can be averaged together to obtain an average value that reflects an overall substrate thickness. A more accurate measurement of the overall substrate thickness can be obtained by performing multiple measurements and averaging the measurements together. Using the average value, polishing can be adjusted to ensure that the substrate achieves a desired planarized thickness profile. | 06-11-2009 |
20090156098 | Automatic Gain Control - Methods and apparatus for automatic gain control. A film on a substrate is polished by a chemical mechanical polisher that includes a polishing pad and an in-situ monitoring system. The polishing pad includes a first portion, and the in-situ monitoring system includes a light source and a light detector. The light source emits light, and light emitted from the light source is directed through the first portion and to a surface of the film being polished. Light reflecting from the surface of the film being polished and passing through the first portion is received at the light detector. An electronic signal is generated based on the light received at the light detector. When the electronic signal is evaluated not to satisfy one or more constraints, a gain for the light detector is adjusted so that the electronic signal would satisfy the one or more constraints. | 06-18-2009 |
20090253351 | FRICTION SENSOR FOR POLISHING SYSTEM - A system method and apparatus to monitor a frictional coefficient of a substrate undergoing polishing is described. A polishing pad assembly includes a polishing layer including a polishing surface, and a substrate contacting member flexibly coupled to the polishing layer having a top surface to contact an exposed surface of a substrate. At least a portion of the top surface is substantially coplanar with the polishing surface. A sensor is provided to measure a lateral displacement of the substrate contacting member. Some embodiments may provide accurate endpoint detection during chemical mechanical polishing to indicate the exposure of an underlying layer. | 10-08-2009 |
20090262353 | METHODS AND APPARATUS FOR MEASURING SUBSTRATE EDGE THICKNESS DURING POLISHING - Systems, methods and apparatus are provided for determining a substrate polishing endpoint. The invention includes a light source adapted to transmit light to an edge of a substrate; one or more detectors adapted to detect an arrangement of light reflected from the substrate edge; and a controller adapted to determine a polishing endpoint for the substrate edge based on the arrangement of reflected light. Numerous other aspects are provided. | 10-22-2009 |
20090305610 | MULTIPLE WINDOW PAD ASSEMBLY - A method and apparatus for detecting and obtaining a metric indicative of a polishing process is described. The apparatus includes a polishing pad having an optically transparent region adapted to obtain polishing metric from at least one substrate from at least two distinct radial positions of the polishing pad. The method includes obtaining a polishing metric from at least two substrates being polished simultaneously on a single polishing pad. | 12-10-2009 |
20100056023 | Adjusting Polishing Rates by Using Spectrographic Monitoring of a Substrate During Processing - A computer-implemented method includes receiving a sequence of current spectra of reflected light from a substrate; comparing each current spectrum from the sequence of current spectra to a plurality of reference spectra from a reference spectra library to generate a sequence of best-match reference spectra; determining a goodness of fit for the sequence of best-match reference spectra; and determining at least one of whether to adjust a polishing rate or an adjustment for the polishing rate, based on the goodness of fit. | 03-04-2010 |
20100103422 | GOODNESS OF FIT IN SPECTROGRAPHIC MONITORING OF A SUBSTRATE DURING PROCESSING - A sequence of current spectra is obtained with an in-situ optical monitoring system, and each current spectrum is compared to a plurality of reference spectra from a plurality of reference spectra libraries. The library that provides a best fit to the sequence of current spectra is determined, and a polishing endpoint is determined based on the sequence of current spectra and the library that provides a best fit to the sequence of current spectra. | 04-29-2010 |
20100105288 | MULTIPLE LIBRARIES FOR SPECTROGRAPHIC MONITORING OF ZONES OF A SUBSTRATE DURING PROCESSING - Methods, systems, and apparatus, including computer program products, for spectrographic monitoring of a substrate during chemical mechanical polishing are described. In one aspect, a computer-implemented method includes receiving a first sequence of current spectra of reflected light from a first zone of a substrate. A second sequence of current spectra of reflected light from a second zone of the substrate is received. Each current spectrum from the first sequence of current spectra is compared to a plurality of reference spectra from a first reference spectra library to generate a first sequence of best-match reference spectra. Each current spectrum from the second sequence of current spectra is compared to a plurality of reference spectra from a second reference spectra library to generate a second sequence of best-match reference spectra. The second reference spectra library is distinct from the first reference spectra library. | 04-29-2010 |
20100114532 | WEIGHTED SPECTROGRAPHIC MONITORING OF A SUBSTRATE DURING PROCESSING - A substrate having an outermost layer undergoing polishing and at least one underlying layer is irradiated with light. A sequence of current spectra is obtained with an in-situ optical monitoring system, a current spectrum from the sequence of current spectra being a spectrum of the light reflected from the substrate, wherein the current spectrum includes a range of wavelengths and, for all wavelengths in the range of wavelengths, a value corresponding to a wavelength. Further, a value of the current spectrum corresponding to a wavelength is modified with at least one value in a gain factor spectrum, wherein the gain factor spectrum includes a first range of wavelengths and, for all wavelengths in the first range of wavelengths, a value corresponding to a wavelength. The polishing of the outermost layer of the substrate is then changed based upon the modified value of the current spectrum. | 05-06-2010 |
20100120330 | ENDPOINT CONTROL OF MULTIPLE-WAFER CHEMICAL MECHANICAL POLISHING - A computer-implemented method includes polishing substrates simultaneously in a polishing apparatus. Each substrate has a polishing rate independently controllable by an independently variable polishing parameter. Measurement data that varies with the thickness of each of the substrates is acquired from each of the substrates during polishing with an in-situ monitoring system. A projected thickness that each substrate will have at a target time is determined based on the measurement data. The polishing parameter for at least one substrate is adjusted to adjust the polishing rate of the at least one substrate such that the substrates have closer to the same thickness at the target time than without the adjustment. | 05-13-2010 |
20100120331 | ENDPOINT CONTROL OF MULTIPLE-WAFER CHEMICAL MECHANICAL POLISHING - A computer-implemented method includes polishing substrates simultaneously in a polishing apparatus. Each substrate has a polishing rate independently controllable by an independently variable polishing parameter. Measurement data that varies with the thickness of each of the substrates is acquired from each of the substrates during polishing with an in-situ monitoring system. A projected time at which each substrate will reach a target thickness is determined based on the measurement data. The polishing parameter for at least one substrate is adjusted to adjust the polishing rate of the at least one substrate such that the substrates reach the target thickness closer to the same time than without the adjustment. | 05-13-2010 |
20100120333 | In-Line Wafer Thickness Sensing - A method of forming bare silicon substrates is described. A bare silicon substrate is measured, wherein measuring is performed by a non-contact capacitance measurement device to obtain a signal at a point on the substrate. The signal or a thickness indicated by the signal is communicated to a controller. An adjusted polishing parameter according to the signal or thickness indicated by the signal is determined. After determining an adjusted polishing parameter, the bare silicon substrate is polished on a polisher using the adjusted polishing parameter. | 05-13-2010 |
20100124792 | EDDY CURRENT SENSOR WITH ENHANCED EDGE RESOLUTION - An apparatus for monitoring the thickness of a conductive layer on a substrate includes a support to hold a substrate having a conductive layer, an eddy current monitoring system including a first plurality of core portions, and a motor to cause relative motion between the support and the eddy current monitoring system such that the substrate moves across the first plurality of core portions in a direction that defines a first axis. At least one core portion is positioned further from a second axis than at least two other core portions. The second axis is orthogonal to the first axis. | 05-20-2010 |
20100124870 | Semi-Quantitative Thickness Determination - While a substrate is polished, it is also irradiated with light from a light source. A current spectrum of the light reflected from the surface of the substrate is measured. A selected peak, having a first parameter value, is identified in the current spectrum. A value of a second parameter associated with the first parameter is determined from a lookup table using a processor. Depending on the value of the second parameter, the polishing of the substrate is changed. An initial spectrum of light reflected from the substrate before the polishing of the substrate can be measured and a wavelength corresponding to a selected peak of the initial spectrum can be determined. | 05-20-2010 |
20100129939 | USING OPTICAL METROLOGY FOR WITHIN WAFER FEED FORWARD PROCESS CONTROL - A method of controlling the polishing of a substrate includes polishing a substrate on a first platen using a first set of parameters, obtaining first and second sequences of measured spectra from first and second regions of the substrate with an in-situ optical monitoring system, generating first and second sequences of values from the first and second sequences of measured spectra, fitting first and second linear functions to the first and second sequences of values, determining a difference between the first linear function and the second linear function, adjusting at least one parameter of a second set of parameters based on the difference, and polishing the substrate on a second platen using the adjusted parameter. | 05-27-2010 |
20100130100 | USING OPTICAL METROLOGY FOR WAFER TO WAFER FEED BACK PROCESS CONTROL - A method of controlling the polishing of a substrate includes polishing a substrate on a first platen using a first set of parameters, obtaining first and second sequences of measured spectra from first and second regions of the substrate with an in-situ optical monitoring system, generating first and second sequences of values from the first and second sequences of measured spectra, fitting first and second linear functions to the first and second sequences of values, determining a difference between the first linear function and the second linear function, adjusting at least one parameter of the first set of parameters based on the difference, and polishing the second substrate on the first platen using the adjusted parameter. | 05-27-2010 |
20100184357 | Polishing Pad and System with Window Support - A polishing system includes a polishing pad having a solid light-transmissive window, an optical fiber having an end, and a spacer having a vertical aperture therethrough. A bottom surface of the spacer contacts the end of the optical fiber, a top surface of the spacer contacts the underside of the window, and the vertical aperture is aligned with the optical fiber. | 07-22-2010 |
20100185314 | GST Film Thickness Monitoring - In polishing a substrate having a layer of GST disposed over an underlying layer, during polishing, a non-polarized light beam is directed onto the layer of GST. The non-polarized light beam reflects from the first substrate to generate a reflected light beam having an infra-red component. A sequence of measurements of intensity of the infra-red component of the reflected light beam are generated, and, in a processor, a time at which the sequence of measurements exhibits a predefined feature is determined. | 07-22-2010 |
20100217430 | SPECTROGRAPHIC MONITORING OF A SUBSTRATE DURING PROCESSING USING INDEX VALUES - Methods, systems, and apparatus for spectrographic monitoring of a substrate during chemical mechanical polishing are described. In one aspect, a computer-implemented method includes storing a library having a plurality of reference spectra, each reference spectrum of the plurality of reference spectra having a stored associated index value, measuring a sequence of spectra in-situ during polishing to obtain measured spectra, for each measured spectrum of the sequence of spectra, finding a best matching reference spectrum to generate a sequence of best matching reference spectra, determining the associated index value for each best matching spectrum from the sequence of best matching reference spectra to generate a sequence of index values, fitting a linear function to the sequence of index values, and halting the polishing either when the linear function matches or exceeds a target index or when the associated index value from the determining step matches or exceeds the target index. | 08-26-2010 |
20100261413 | Determining Physical Property of Substrate - A method of determining a physical property of a substrate includes recording a first spectrum obtained from a substrate, the first spectrum being obtained during a polishing process that alters a physical property of the substrate. The method includes identifying, in a database, at least one of several previously recorded spectra that is similar to the recorded first spectrum. Each of the spectra in the database has a physical property value associated therewith. The method includes generating a signal indicating that a first value of the physical property is associated with the first spectrum, the first value being determined using the physical property value associated with the identified previously recorded spectrum in the database. A system for determining a physical property of a substrate includes a polishing machine, an endpoint determining module, and a database. | 10-14-2010 |
20100269417 | TREATMENT OF POLISHING PAD WINDOW - A window of solid light-transmissive polymer is formed in a polishing pad, and at least one surface of the window is treated to increase the smoothness of the at least one surface. | 10-28-2010 |
20100297916 | METHODS OF USING OPTICAL METROLOGY FOR FEED BACK AND FEED FORWARD PROCESS CONTROL - A method includes polishing a substrate on a first platen using a first set of parameters, obtaining a plurality of measured spectra from at least two zones, comparing the plurality of measured spectra with a reference spectrum to evaluate the thickness of each of the at least two zones of the substrate, comparing a thickness of a first zone with a thickness of a second zone, determining whether the thickness of the first zone falls within a predetermined range of the thickness of the second zone, and if the thickness does not fall within the predetermined range, at least one of a) adjusting at least one parameter of the first set and polishing a second substrate on the first platen using the adjusted parameters, or b) adjusting at least one parameter of a second set and polishing the substrate on a second platen using the adjusted parameters. | 11-25-2010 |
20110046918 | METHODS AND APPARATUS FOR GENERATING A LIBRARY OF SPECTRA - A method of generating a library from a reference substrate for use in processing product wafers is described. The method includes measuring substrate characteristics at a plurality of well-defined points of a reference substrate, measuring spectra at plurality of measurement points of the reference substrate, there being more measurement points than well-defined points, and associating measured spectra with measured substrate characteristics. | 02-24-2011 |
20110104987 | ENDPOINT METHOD USING PEAK LOCATION OF SPECTRA CONTOUR PLOTS VERSUS TIME - In one aspect, a method of polishing includes polishing a substrate, and receiving an identification of a selected spectral feature and a characteristic of the selected spectral feature to monitor during polishing. The method includes measuring a sequence of spectra of light reflected from the substrate while the substrate is being polished, where at least some of the spectra of the sequence differ due to material being removed during the polishing. The method of polishing includes determining a value of a characteristic of the selected spectral feature for each of the spectra in the sequence of spectra to generate a sequence of values for the characteristic, fitting a function to the sequence of values, and determining either a polishing endpoint or an adjustment for a polishing rate based on the function. | 05-05-2011 |
20110189856 | High Sensitivity Real Time Profile Control Eddy Current Monitoring System - A method of chemical mechanical polishing a metal layer on a substrate includes polishing the metal layer on the substrate at first and second polishing stations, monitoring thickness of the metal layer during polishing at the first and second polishing station with first and second eddy current monitoring systems having different resonant frequencies, and controlling pressures applied by a carrier head to the substrate during polishing at the first and second polishing stations to improve uniformity based on thickness measurements from the first and second eddy current monitoring systems. | 08-04-2011 |
20110189925 | High Sensitivity Real Time Profile Control Eddy Current Monitoring System - An apparatus for chemical mechanical polishing includes a platen having a surface to support a polishing pad, and an eddy current monitoring system to generate an eddy current signal. The eddy current monitoring system includes a core and a coil wound around a portion of the core. The core includes a back portion, a first prong extending from the back portion in a first direction normal to the surface of the platen and having a width in a second direction parallel to the surface of the platen, and second and third prongs extending from the back portion in parallel with the first protrusion, the second and third prongs positioned on opposite sides of and equidistant from the first prong. A spacing between each of the second and third prongs and the first prong is approximately equal to twice the width of the first prong. | 08-04-2011 |
20110195528 | POLISHING SYSTEM WITH IN-LINE AND IN-SITU METROLOGY - A computer-implemented method for process control in chemical mechanical polishing in which an initial pre-polishing thickness of a substrate is measured at a metrology station, a parameter of an endpoint algorithm is determined from the initial thickness of the substrate, a substrates is polished at a polishing station, and polishing stops when an endpoint criterion is detected using the endpoint algorithm. | 08-11-2011 |
20110212673 | POLISHING PAD WITH PARTIALLY RECESSED WINDOW - A polishing pad has an opaque polishing layer with an aperture therethrough and a polishing surface, and a solid light-transmissive window in the aperture. The solid light-transmissive window includes an outer portion secured to the polishing layer and an inner portion secured to the outer portion. The outer portion has a upper surface recessed relative to the polishing surface, whereas the inner portion has an upper surface that is substantially co-planar with the polishing surface. | 09-01-2011 |
20110256805 | Adaptively Tracking Spectrum Features For Endpoint Detection - A method of controlling polishing includes polishing a substrate, monitoring a substrate during polishing with an in-situ monitoring system, generating a sequence of values from measurements from the in-situ monitoring system, fitting a non-linear function to the sequence of values, determining a projected time at which the non-linear function reaches a target value; and determining at least one of a polishing endpoint or an adjustment for a polishing rate based on the projected time. | 10-20-2011 |
20110256818 | Molding Windows in Thin Pads - A polishing pad includes a polishing layer having a polishing surface, an adhesive layer on a side of the polishing layer opposite the polishing layer, and a solid light-transmitting window extending through and molded to the polishing layer. The solid light-transmitting window has an upper portion with a first lateral dimension and a lower portion with a second lateral dimension that is smaller than the first lateral dimension. A top surface of the solid light-transmitting window coplanar with the polishing surface and a bottom surface of the solid light-transmitting window coplanar with a lower surface of the adhesive layer. | 10-20-2011 |
20110281510 | Pad Window Insert - A polishing pad includes a polishing layer having a polishing surface, an adhesive layer on a side of the polishing layer opposite the polishing layer, and a solid light-transmitting window extending through and molded to the polishing layer. The solid light-transmitting window has an upper portion with a first lateral dimension and a lower portion with a second lateral dimension that is smaller than the first lateral dimension. A top surface of the solid light-transmitting window coplanar with the polishing surface and a bottom surface of the solid light-transmitting window coplanar with a lower surface of the adhesive layer. | 11-17-2011 |
20110282477 | ENDPOINT CONTROL OF MULTIPLE SUBSTRATES WITH MULTIPLE ZONES ON THE SAME PLATEN IN CHEMICAL MECHANICAL POLISHING - A plurality of substrates are polished simultaneously on the same polishing pad. A sequence of spectra is measured from each zone of each substrate, and for each measured spectrum in the sequence of spectra for each zone of each substrate, a best matching reference spectrum is determined from a library of reference spectra. For each zone of each substrate, a linear function is fit to a sequence of index values associated with the best matching reference spectra. For at least one zone, a projected time at which the zone will reach a target index value is determined based on the linear function, and the polishing parameter for at least one zone on at least one substrate is adjusted such that the at least one zone of the at least one substrate has closer to the target index at the projected time than without such adjustment. | 11-17-2011 |
20110294400 | Determining Physical Property of Substrate - A method of determining a physical property of a substrate includes recording a first spectrum obtained from a substrate, the first spectrum being obtained during a polishing process that alters a physical property of the substrate. The method includes identifying, in a database, at least one of several previously recorded spectra that is similar to the recorded first spectrum. Each of the spectra in the database has a physical property value associated therewith. The method includes generating a signal indicating that a first value of the physical property is associated with the first spectrum, the first value being determined using the physical property value associated with the identified previously recorded spectrum in the database. A system for determining a physical property of a substrate includes a polishing machine, an endpoint determining module, and a database. | 12-01-2011 |
20110294402 | Eddy Current System for In-Situ Profile Measurement - An eddy current monitoring system may include an elongated core. One or more coils may be coupled with the elongated core for producing an oscillating magnetic field that may couple with one or more conductive regions on a wafer. The core may be translated relative to the wafer to provide improved resolution while maintaining sufficient signal strength. An eddy current monitoring system may include a DC-coupled marginal oscillator for producing an oscillating magnetic field at a resonant frequency, where the resonant frequency may change as a result of changes to one or more conductive regions. Eddy current monitoring systems may be used to enable real-time profile control. | 12-01-2011 |
20110300775 | Control of Overpolishing of Multiple Substrates on the Same Platen in Chemical Mechanical Polishing - A polishing method includes simultaneously polishing two substrates, a first substrate and a second substrate, on the same polishing pad. A default overpolishing time is stored and an in-situ monitoring system monitors the two substrates. The in-situ monitoring system further determines a first polishing endpoint time and a second polishing endpoint time of the first and second substrates, respectively. The polishing method further includes calculating an overpolishing stop time where the overpolishing stop time is between the first polishing endpoint time plus the default overpolishing time and the second polishing endpoint time plus the default overpolishing time. Polishing of the first substrate is continued past the first polishing endpoint time and polishing of the second substrate is continued past the second polishing endpoint time. Polishing of both the first substrate and the second substrate is halted simultaneously at the overpolishing stop time. | 12-08-2011 |
20120028377 | USING OPTICAL METROLOGY FOR WITHIN WAFER FEED FORWARD PROCESS CONTROL - A method of controlling the polishing of a substrate includes polishing a substrate on a first platen using a first set of parameters, obtaining first and second sequences of measured spectra from first and second regions of the substrate with an in-situ optical monitoring system, generating first and second sequences of values from the first and second sequences of measured spectra, fitting first and second linear functions to the first and second sequences of values, determining a difference between the first linear function and the second linear function, adjusting at least one parameter of a second set of parameters based on the difference, and polishing the substrate on a second platen using the adjusted parameter. | 02-02-2012 |
20120028813 | Selecting Reference Libraries For Monitoring Of Multiple Zones On A Substrate - A method of configuring a polishing monitoring system includes receiving user input selecting a plurality of libraries, each library of the plurality of libraries comprising a plurality of reference spectra for use in matching to measured spectra during polishing, each reference spectrum of the plurality of reference spectra having an associated index value, for a first zone of a substrate, receiving user input selecting a first subset of the plurality of libraries, and for a second zone of the substrate, receiving user input selecting a second subset of the plurality of libraries. | 02-02-2012 |
20120064801 | Feedback Control of Polishing Using Optical Detection of Clearance - A method of controlling polishing includes polishing a first substrate having an overlying layer on an underlying layer or layer structure. During polishing, the substrate is monitored with an in-situ monitoring system to generate a sequence of measurements. The measurements are sorted into groups, each group associated with a different zone of a plurality of zones on the substrate. For each zone, a time at which the overlying layer is cleared is determined based on the measurements from the associated group. At least one second adjusted polishing pressure for at least zone is calculated based on a pressure applied in the at least one zone during polishing the substrate, the time for the at least one zone, and the time for another zone. A second substrate is polished using the at least one adjusted polishing pressure. | 03-15-2012 |
20120100642 | Spectra Based Endpointing for Chemical Mechanical Polishing - A computer implemented method of monitoring a polishing process includes, for each sweep of a plurality of sweeps of an optical sensor across a substrate undergoing polishing, obtaining a plurality of current spectra, each current spectrum of the plurality of current spectra being a spectrum resulting from reflection of white light from the substrate, for each sweep of the plurality of sweeps, determining a difference between each current spectrum and each reference spectrum of a plurality of reference spectra to generate a plurality of differences, for each sweep of the plurality of sweeps, determining a smallest difference of the plurality of differences, thus generating a sequence of smallest difference, and determining a polishing endpoint based on the sequence of smallest differences. | 04-26-2012 |
20120196511 | Gathering Spectra From Multiple Optical Heads - A polishing apparatus includes a platen to hold a polishing pad having a plurality of optical apertures, a carrier head to hold a substrate against the polishing pad, a motor to generate relative motion between the carrier head and the platen, and an optical monitoring system. The optical monitoring system includes at least one light source, a common detector, and an optical assembly configured to direct light from the at least one light source to each of a plurality of separated positions in the platen, to direct light from each position of the plurality of separated positions to the substrate as the substrate passes over said each position, to receive reflected light from the substrate as the substrate passes over said each position, and to direct the reflected light from each of the plurality of separated positions to the common detector. | 08-02-2012 |
20120227903 | Automatic Gain Control - Methods and apparatus for automatic gain control. A film on a substrate is polished by a chemical mechanical polisher that includes a polishing pad and an in-situ monitoring system. The polishing pad includes a first portion, and the in-situ monitoring system includes a light source and a light detector. The light source emits light, and light emitted from the light source is directed through the first portion and to a surface of the film being polished. Light reflecting from the surface of the film being polished and passing through the first portion is received at the light detector. An electronic signal is generated based on the light received at the light detector. When the electronic signal is evaluated not to satisfy one or more constraints, a gain for the light detector is adjusted so that the electronic signal would satisfy the one or more constraints. | 09-13-2012 |
20120276661 | HIGH SENSITIVITY EDDY CURRENT MONITORING SYSTEM - A method of chemical mechanical polishing a substrate includes polishing a metal layer on the substrate at a polishing station, monitoring thickness of the metal layer during polishing at the polishing station with an eddy current monitoring system, and controlling pressures applied by a carrier head to the substrate during polishing of the metal layer at the polishing station based on thickness measurements of the metal layer from the eddy current monitoring system to reduce differences between an expected thickness profile of the metal layer and a target profile, wherein the metal layer has a resistivity greater than 700 ohm Angstroms. | 11-01-2012 |
20120276662 | EDDY CURRENT MONITORING OF METAL FEATURES - A method of chemical mechanical polishing a substrate includes polishing a plurality of discrete separated metal features of a layer on the substrate at a polishing station, using an eddy current monitoring system to monitor thickness of the metal features in the layer, and controlling pressures applied by a carrier head to the substrate during polishing of the layer at the polishing station based on thickness measurements of the metal features from the eddy current monitoring system to reduce differences between an expected thickness profile of the metal feature and a target profile. | 11-01-2012 |
20120276814 | AUTOMATIC SELECTION OF REFERENCE SPECTRA LIBRARY - A computer-implemented method of generating reference spectra includes polishing a plurality of set-up substrates, the plurality of set-up substrates comprising at least three set-up substrates, measuring a sequence of spectra from each of the plurality of set-up substrates during polishing with an in-situ optical monitoring system to provide a plurality of sequences of spectra, generating a plurality of sequences of potential reference spectra from the plurality of sequences of spectra, determining which sequence of potential reference spectra of the plurality of sequences provides a best match to remaining sequences of the plurality of sequences, and storing the sequence of potential reference spectra determined to provide the best match as reference spectra, and selecting and storing the sequence of potential reference spectra. | 11-01-2012 |
20120276817 | EDDY CURRENT MONITORING OF METAL RESIDUE OR METAL PILLARS - A method of chemical mechanical polishing a substrate includes polishing a metal layer on the substrate at a polishing station, monitoring thickness of the metal layer during polishing at the polishing station with an eddy current monitoring system, and halting polishing when the eddy current monitoring system indicates that residue of the metal layer is removed from an underlying layer and a top surface of the underlying layer is exposed. | 11-01-2012 |
20120289124 | ENDPOINT DETECTION USING SPECTRUM FEATURE TRAJECTORIES - A method of polishing includes polishing a substrate, making a sequence of measurements of light reflected from the substrate while the substrate is being polished, at least some of the measurements of the sequence of measurements differing due to material being removed during polishing, for each measurement in the sequence, determining a first value of a first characteristic and a second value of a different second characteristic of the light to generate a sequence of first values and second values, storing a predetermined path in a coordinate space of the first characteristic and the second characteristic, for each measurement in the sequence, determining a position on the path based on the first value and the second value, and determining at least one of a polishing endpoint or an adjustment for a polishing rate based on the position on the path. | 11-15-2012 |
20120323355 | SPECTROGRAPHIC MONITORING OF A SUBSTRATE DURING PROCESSING USING INDEX VALUES - Methods, systems, and apparatus for spectrographic monitoring of a substrate during chemical mechanical polishing are described. In one aspect, a computer-implemented method includes storing a library having a plurality of reference spectra, each reference spectrum of the plurality of reference spectra having a stored associated index value, measuring a sequence of spectra in-situ during polishing to obtain measured spectra, for each measured spectrum of the sequence of spectra, finding a best matching reference spectrum to generate a sequence of best matching reference spectra, determining the associated index value for each best matching spectrum from the sequence of best matching reference spectra to generate a sequence of index values, fitting a linear function to the sequence of index values, and halting the polishing either when the linear function matches or exceeds a target index or when the associated index value from the determining step matches or exceeds the target index. | 12-20-2012 |
20130059499 | Semi-Quantitative Thickness Determination - While a substrate is polished, it is also irradiated with light from a light source. A current spectrum of the light reflected from the surface of the substrate is measured. A selected peak, having a first parameter value, is identified in the current spectrum. A value of a second parameter associated with the first parameter is determined from a lookup table using a processor. Depending on the value of the second parameter, the polishing of the substrate is changed. An initial spectrum of light reflected from the substrate before the polishing of the substrate can be measured and a wavelength corresponding to a selected peak of the initial spectrum can be determined. | 03-07-2013 |
20130167614 | FRICTION SENSOR FOR POLISHING SYSTEM - A system method and apparatus to monitor a frictional coefficient of a substrate undergoing polishing is described. A polishing pad assembly includes a polishing layer including a polishing surface, and a substrate contacting member flexibly coupled to the polishing layer having a top surface to contact an exposed surface of a substrate. At least a portion of the top surface is substantially coplanar with the polishing surface. A sensor is provided to measure a lateral displacement of the substrate contacting member. Some embodiments may provide accurate endpoint detection during chemical mechanical polishing to indicate the exposure of an underlying layer. | 07-04-2013 |
20130204424 | Adjusting Polishing Rates by Using Spectrographic Monitoring of a Substrate During Processing - A computer-implemented method includes receiving a sequence of current spectra of reflected light from a substrate; comparing each current spectrum from the sequence of current spectra to a plurality of reference spectra from a reference spectra library to generate a sequence of best-match reference spectra; determining a goodness of fit for the sequence of best-match reference spectra; and determining at least one of whether to adjust a polishing rate or an adjustment for the polishing rate, based on the goodness of fit. | 08-08-2013 |
20130224890 | Feedback Control Using Detection Of Clearance And Adjustment For Uniform Topography - A method of controlling polishing includes storing a desired ratio representing a ratio for a clearance time of a first zone of a substrate to a clearance time of a second zone of the substrate. During polishing of a first substrate, an overlying layer is monitored, a sequence of measurements is generated, and the measurements are sorted a first group associated with the first zone of the substrate and a second group associated with the second zone on the substrate. A first time and a second time at which the overlying layer is cleared is determined based on the measurements from the first group and the second group, respectively. At least one adjusted polishing pressure is calculated for the first zone based on a first pressure applied in the first zone during polishing the first substrate, the first time, the second time, and the desired ratio. | 08-29-2013 |
20130231032 | POLISHING PAD WITH TWO-SECTION WINDOW HAVING RECESS - A method of forming a polishing pad with a polishing layer having a polishing surface and a back surface. A plurality of grooves are formed on the polishing surface, and an indentation is formed in the back surface of the polishing layer. A region on the polishing surface corresponding to the indentation in the back surface is free of grooves or has shallower grooves. | 09-05-2013 |
20130280827 | METHOD OF CONTROLLING POLISHING USING IN-SITU OPTICAL MONITORING AND FOURIER TRANSFORM - A method of controlling a polishing operation includes polishing a substrate, during polishing obtaining a sequence over time of measured spectra from the substrate with an in-situ optical monitoring system, for each measured spectrum from the sequence of measured spectra applying a Fourier transform to the measured spectrum to generate a transformed spectrum thus generating a sequence of transformed spectra, for each transformed spectrum identifying a peak of interest from a plurality of peaks in the transformed spectrum, for each transformed spectrum determining a position value for the peak of interest in the transformed spectrum thus generating a sequence of position values, and determining at least one of a polishing endpoint or an adjustment of a pressure to the substrate from the sequence of position values. | 10-24-2013 |
20130280989 | USER-INPUT FUNCTIONS FOR DATA SEQUENCES IN POLISHING ENDPOINT DETECTION - A method of controlling polishing includes receiving user input through a graphical user interface selecting a function, the function including at least one parameter that can be varied, polishing a substrate, monitoring a substrate during polishing with an in-situ monitoring system, generating a sequence of values from measurements from the in-situ monitoring system, fitting the function to the sequence of values, the fitting including determining a value of the at least one parameter that provides a best fit of the function to the sequence of values, determining a projected time at which the function equals a target value, and determining at least one of a polishing endpoint or an adjustment for a polishing rate based on the projected time. | 10-24-2013 |
20130295826 | POLISHING PAD FOR ENDPOINT DETECTION AND RELATED METHODS - A polishing pad has a polishing layer with a polishing surface and a back surface. A plurality of grooves are formed on the polishing surface, and an indentation is formed in the back surface of the polishing layer. A region on the polishing surface corresponding to the indentation in the back surface is free of grooves or has shallower grooves. | 11-07-2013 |
20130309951 | THIN POLISHING PAD WITH WINDOW AND MOLDING PROCESS - A polishing pad is described that has a polishing layer with a polishing surface, an adhesive layer on a side of the polishing layer opposite the polishing layer, and a solid light-transmitting window extending through and molded to the polishing layer. The window has a top surface coplanar with the polishing surface and a bottom surface coplanar with a lower surface of the adhesive layer. A method of making a polishing pad includes forming an aperture through a polishing layer and an adhesive layer, securing a backing piece to the adhesive layer on a side opposite a polishing surface of the polishing layer, dispensing a liquid polymer into the aperture, and curing the liquid polymer to form a window. | 11-21-2013 |
20130344625 | ENDPOINTING DETECTION FOR CHEMICAL MECHANICAL POLISHING BASED ON SPECTROMETRY - Methods and apparatus for spectrum-based endpointing. An endpointing method includes selecting a reference spectrum. The reference spectrum is a spectrum of white light reflected from a film of interest on a first substrate and has a thickness greater than a target thickness. The reference spectrum is empirically selected for particular spectrum-based endpoint determination logic so that the target thickness is achieved when endpoint is called by applying the particular spectrum-based endpoint logic. The method includes obtaining a current spectrum. The current spectrum is a spectrum of white light reflected from a film of interest on a second substrate when the film of interest is being subjected to a polishing step and has a current thickness that is greater than the target thickness. The method includes determining, for the second substrate, when an endpoint of the polishing step has been achieved. The determining is based on the reference and current spectra. | 12-26-2013 |
20140024293 | Control Of Overpolishing Of Multiple Substrates On the Same Platen In Chemical Mechanical Polishing - A polishing method includes simultaneously polishing a first substrate and a second substrate on the same polishing pad, storing a default overpolishing time, determining first and second polishing endpoint times of the first and substrates with the in-situ monitoring system, determining a difference between the first and second polishing endpoint times, and determining whether the difference exceeds a threshold. If the difference is less than the threshold, then an overpolishing stop time is calculated and polishing of the first substrate and the second substrates is halted simultaneously at the overpolishing stop time. If the difference is greater than the threshold, then first and second overpolishing stop times that equal the first and second endpoint times plus the default overpolishing time are calculated, and polishing of the first and second substrates is halted at the first and second overpolishing stop times, respectively. | 01-23-2014 |
20140030956 | CONTROL OF POLISHING OF MULTIPLE SUBSTRATES ON THE SAME PLATEN IN CHEMICAL MECHANICAL POLISHING - A polishing method includes positioning two substrates in contact with the same polishing pad. Prior to commencement of polishing and while the two substrates are in contact with the polishing pad, two starting values are generated from an in-situ monitoring system. Either a starting polishing time or a pressure applied to one of the substrates can be adjusted so that the two substrates have closer endpoint conditions. During polishing the two substrates are monitored with the in-situ monitoring system to generate a two sequences of values, and a polishing endpoint can be detected or an adjustment for a polishing parameter can be based on the two sequences of values. | 01-30-2014 |
20140039660 | SPECTROGRAPHIC MONITORING OF A SUBSTRATE DURING PROCESSING USING INDEX VALUES - Methods, systems, and apparatus for spectrographic monitoring of a substrate during chemical mechanical polishing are described. In one aspect, a computer-implemented method includes storing a library having a plurality of reference spectra, each reference spectrum of the plurality of reference spectra having a stored associated index value, measuring a sequence of spectra in-situ during polishing to obtain measured spectra, for each measured spectrum of the sequence of spectra, finding a best matching reference spectrum to generate a sequence of best matching reference spectra, determining the associated index value for each best matching spectrum from the sequence of best matching reference spectra to generate a sequence of index values, fitting a linear function to the sequence of index values, and halting the polishing either when the linear function matches or exceeds a target index or when the associated index value from the determining step matches or exceeds the target index. | 02-06-2014 |
20140045282 | Using Spectra to Determine Polishing Endpoints - Methods of determining a polishing endpoint are described using spectra obtained during a polishing sequence. In particular, techniques for using only desired spectra, faster searching methods and more robust rate determination methods are described. | 02-13-2014 |
20140080232 | PEAK-BASED ENDPOINTING FOR CHEMICAL MECHANICAL POLISHING - A polishing system receives one or more target parameters for a selected peak in a spectrum of light, polishes a substrate, measures a current spectrum of light reflected from the substrate while the substrate is being polished, identifies the selected peak in the current spectrum, measures one or more current parameters of the selected peak in the current spectrum, compares the current parameters of the selected peak to the target parameters, and ceases to polish the substrate when the current parameters and the target parameters have a pre defined relationship. | 03-20-2014 |
20140093987 | Residue Detection with Spectrographic Sensor - Detecting residue of a filler material over a patterned underlying layer includes causing relative motion between a probe of an optical metrology system and a substrate, obtaining a plurality of measured spectra with the optical metrology system through the probe from a plurality of different measurement spots within an area on the substrate, comparing each of the plurality of measured spectra to a reference spectrum to generate a plurality of similarity values, the reference spectrum being a spectrum reflected from the filler material, combining the similarity values to generate a scalar value, and determining the presence of residue based on the scalar value. | 04-03-2014 |
20140113524 | ENDPOINTING WITH SELECTIVE SPECTRAL MONITORING - A method of controlling polishing includes polishing a substrate, monitoring the substrate during polishing with an in-situ spectrographic monitoring system to generate a sequence of measured spectra, selecting less than all of the measured spectra to generate a sequence of selected spectra, generating a sequence of values from the sequence of selected spectra, and determining at least one of a polishing endpoint or an adjustment for a polishing rate based on the sequence of values. | 04-24-2014 |
20140127971 | IN-SITU MONITORING SYSTEM WITH MONITORING OF ELONGATED REGION - A method of chemical mechanical polishing a substrate includes polishing a layer on the substrate at a polishing station, monitoring the layer during polishing at the polishing station with an in-situ monitoring system, the in-situ monitoring system monitoring an elongated region and generating a measured signal, computing an angle between a primary axis of the elongated region and a tangent to an edge of the substrate, modifying the measured signal based on the angle to generate a modified signal, and at least one of detecting a polishing endpoint or modifying a polishing parameter based on the modified signal. | 05-08-2014 |
20140134758 | TECHNIQUES FOR MATCHING SPECTRA - A method of controlling processing of a substrate includes measuring a spectrum reflected from the substrate, for each partition of a plurality of partitions of the measured spectrum, computing a partition value based on the measured spectrum within the partition to generate a plurality of partition values, for each reference spectrum signature of a plurality of reference spectrum signatures, determining a membership function for each partition, for each partition, computing a membership value based on the membership function for the partition and the partition value for the partition to generate a plurality of groups of membership values with each group of the plurality of groups associated with a reference spectrum signature, selecting a best matching reference spectrum signature from the plurality of reference spectra signatures based on the plurality of groups of membership values, and determining a characterizing value associated with the best matching reference spectrum signature. | 05-15-2014 |
20140141695 | Multi-Platen Multi-Head Polishing Architecture - A polishing apparatus includes a plurality of stations supported on a platform, the plurality of stations including at least two polishing stations and a transfer station, each polishing station including a platen to support a polishing pad, a plurality of carrier heads suspended from and movable along a track such that each polishing station is selectively positionable at the stations, and a controller configured to control motion of the carrier heads along the track such that during polishing at each polishing station only a single carrier head is positioned in the polishing station. | 05-22-2014 |
20140141696 | Polishing System with In-Sequence Sensor - A polishing apparatus includes a plurality of stations supported on a platform, the plurality of stations including at least two polishing stations and a transfer station, each polishing station including a platen to support a polishing pad, a plurality of carrier heads suspended from and movable along a track such that each polishing station is selectively positionable at the stations, and a controller configured to control motion of the carrier heads along the track such that during polishing at each polishing station only a single carrier head is positioned in the polishing station. | 05-22-2014 |
20140206259 | REFLECTIVITY MEASUREMENTS DURING POLISHING USING A CAMERA - A substrate polishing system includes a platen to support a polishing surface, a carrier head configured to hold a substrate against the polishing surface during polishing, a light source configured to direct a light beam onto a surface of the substrate, a detector including an array of detection elements, and a controller. The detector is configured to detect reflections of the light beam from an area of the surface, and is configured to generate an image having pixels representing regions on the substrate having a length less than 0.1 mm. The controller is configured to receive the image and to detect clearance of a metal layer from an underlying layer on the substrate based on the image. | 07-24-2014 |
20140222188 | ENDPOINT CONTROL OF MULTIPLE SUBSTRATES OF VARYING THICKNESS ON THE SAME PLATEN IN CHEMICAL MECHANICAL POLISHING - A difference between a first expected required polish time for a first substrate and a second expected required polish time for a second substrate is determined using a first pre-polish thickness and a second pre-polish thickness measured at an in-line metrology station. A duration of an initial period is determined based on the difference between the first expected required polish time and the second expected required polish time. For the initial period at a beginning of a polishing operation, no pressure is applied to whichever of the first substrate and the second substrate has a lesser expected required polish time while simultaneously pressure is applied to whichever of the first substrate and the second substrate has a greater expected required polish time. After the initial period, pressure is applied to both the first substrate and the second substrate. | 08-07-2014 |
20140242878 | WEIGHTED REGRESSION OF THICKNESS MAPS FROM SPECTRAL DATA - A method of controlling a polishing operation includes measuring a plurality of spectra at a plurality of different positions on a substrate to provide a plurality of measured spectra. For each measured spectrum of the plurality of measured spectra, a characterizing value is generated based on the measured spectrum. For each characterizing value, a goodness of fit of the measured spectrum to another spectrum used in generating the characterizing value is determined. A wafer-level characterizing value map is generated by applying a regression to the plurality of characterizing values with the plurality of goodnesses of fit used as weighting factors in the regression. A polishing endpoint or a polishing parameter of the polishing apparatus is adjusted based on the wafer-level characterizing map, and the substrate or a subsequent substrate is polished in the polishing apparatus with the adjusted polishing endpoint or polishing parameter. | 08-28-2014 |
20140242879 | PATH FOR PROBE OF SPECTROGRAPHIC METROLOGY SYSTEM - A method of operating a polishing system includes polishing a substrate at a polishing station, the substrate held by a carrier head during polishing, transporting the substrate to an in-sequence optical metrology system positioned between the polishing station and another polishing station or a transfer station, measuring a plurality of spectra reflected from the substrate with a probe of the optical metrology system while moving the carrier head to cause the probe to traverse a path across the substrate and while the probe remains stationary, the path across the substrate comprising either a plurality of concentric circles or a plurality of substantially radially aligned arcuate segments, and adjusting a polishing endpoint or a polishing parameter of the polishing system based on one or more characterizing values generated based on at least some of the plurality of spectra. | 08-28-2014 |
20140242881 | FEED FORWARD PARAMETER VALUES FOR USE IN THEORETICALLY GENERATING SPECTRA - A method of controlling a polishing operation is described. A controller stores an optical model for a layer stack having a plurality of layers and a plurality of input parameters including a first parameter and a second parameter. The controller stores data defining a plurality of default values for the first parameter and measures an optical property of a substrate and generates a second value. Using the optical model and the second value and iterating over the first values, a number of reference spectra are calculated. A spectrum is measured and the measured spectrum is matched to the reference spectra and the best matched reference spectrum is determined. The first value of the best matched reference spectrum is determined and is used to adjust a polishing endpoint or a polishing parameter of a polishing apparatus. | 08-28-2014 |
20140242883 | DETERMINATION OF WAFER ANGULAR POSITION FOR IN-SEQUENCE METROLOGY - A polishing apparatus includes a carrier head configured to hold a wafer in a first plane, the wafer having a perimeter and a fiducial, a drive shaft having an axis perpendicular to the first plane and configured to rotate the carrier head about the axis, a light source configured to direct light onto an outer face of the wafer at a position adjacent the perimeter of the wafer; a detector configured to detect the light collected from the wafer while the drive shaft rotates the carrier head and the wafer; and a controller configured to receive a first signal indicating an angular position of the drive shaft and receive a second signal from the detector, the controller configured to determine based on the first signal and the second signal an angular position of the fiducial with respect the carrier head. | 08-28-2014 |
20140273745 | X-RAY METROLOGY FOR CONTROL OF POLISHING - A method of controlling a polishing operation includes receiving a first measurement of a first amount of metal on a substrate made by a first x-ray monitoring system after a first metal layer is deposited on the substrate and before a second metal layer is deposited on the substrate, transferring the substrate to a carrier head of a chemical mechanical polishing apparatus the substrate after the second metal layer is deposited on the substrate, making a second measurement of a second amount of metal on the substrate with a second x-ray monitoring system in the chemical mechanical polishing apparatus, comparing the first measurement to the second measurement to determine a difference, and adjusting a polishing endpoint or a polishing parameter of the polishing apparatus based on the difference. | 09-18-2014 |
20140316550 | Spectra Based Endpointing for Chemical Mechanical Polishing - A computer implemented method of monitoring a polishing process includes, for each sweep of a plurality of sweeps of an optical sensor across a substrate undergoing polishing, obtaining a plurality of current spectra, each current spectrum of the plurality of current spectra being a spectrum resulting from reflection of white light from the substrate, for each sweep of the plurality of sweeps, determining a difference between each current spectrum and each reference spectrum of a plurality of reference spectra to generate a plurality of differences, for each sweep of the plurality of sweeps, determining a smallest difference of the plurality of differences, thus generating a sequence of smallest difference, and determining a polishing endpoint based on the sequence of smallest differences. | 10-23-2014 |