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 |
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 |
20100035519 | REMOVABLE OPTICAL MONITORING SYSTEM FOR CHEMICAL MECHANICAL POLISHING - A polishing system includes a platen having a top surface to receive a polishing pad, a recess in the top surface, and a cavity inside the platen spaced from the recess, a carrier head to hold a surface of a substrate against the polishing pad on the platen, a monitoring module located in the cavity, the monitoring module including a light source and a detector, an optical head removably mounted in the recess in the top surface platen, and an optical fiber having a proximate end coupled to the monitoring module and a distal end held by the optical head holding the distal end of the optical fiber in a position to direct light through a window in the polishing pad to the surface of the substrate and receive reflected light from the surface of the substrate. | 02-11-2010 |
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 |
20100075582 | POLISHING PAD ASSEMBLY WITH GLASS OR CRYSTALLINE WINDOW - Methods and apparatus for providing a chemical mechanical polishing pad. The pad includes a polishing layer having a top surface and a bottom surface. The pad includes an aperture having a first opening in the top surface and a second opening in the bottom surface. The top surface is a polishing surface. The pad includes a window that includes a first portion made of soft plastic and a crystalline or glass like second portion. The window is transparent to white light. The window is situated in the aperture so that the first portion plugs the aperture and the second portion is on a bottom side of the first portion, wherein the first portion acts a slurry-tight barrier. | 03-25-2010 |
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 |
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 |
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 |
20100284007 | Spectrum Based Endpointing For Chemical Mechanical Polishing - 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. | 11-11-2010 |
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 |
20110209412 | METHOD OF MAKING POLISHING PAD ASSEMBLY WITH GLASS OR CRYSTALLINE WINDOW - Methods and apparatus for providing a chemical mechanical polishing pad. The pad includes a polishing layer having a top surface and a bottom surface. The pad includes an aperture having a first opening in the top surface and a second opening in the bottom surface. The top surface is a polishing surface. The pad includes a window that includes a first portion made of soft plastic and a crystalline or glass like second portion. The window is transparent to white light. The window is situated in the aperture so that the first portion plugs the aperture and the second portion is on a bottom side of the first portion, wherein the first portion acts a slurry-tight barrier. | 09-01-2011 |
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 |
20110275167 | Endpoint Method Using Peak Location Of Modified Spectra - A method of optically monitoring a substrate during polishing includes receiving an identification of a selected spectral feature and a characteristic of the selected spectral feature to monitor during polishing, measuring a first spectrum from the substrate during polishing, the first spectrum measured within an initial time following initiation of polishing, measuring a sequence of second spectra from the substrate during polishing, the sequence of second spectra measured after the initial time, for each second spectrum in the sequence of second spectra, removing the first spectrum from the second spectrum to generate a sequence of modified third spectra, determining a value of a characteristic of the selected spectral feature for each third spectrum in the sequence of third spectra to generate a sequence of values for the characteristic, and determining a polishing endpoint or an adjustment for a polishing rate based on the sequence of values. | 11-10-2011 |
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 |
20110287694 | 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. | 11-24-2011 |
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 |
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 |
20120034845 | TECHNIQUES FOR MATCHING MEASURED SPECTRA TO REFERENCE SPECTRA FOR IN-SITU OPTICAL MONITORING - A method of controlling polishing includes storing a library having a plurality of reference spectra, polishing a substrate, measuring a sequence of spectra of light from the substrate during polishing, for each measured spectrum of the sequence of spectra, finding a best matching reference spectrum using a matching technique other than sum of squared differences to generate a sequence of best matching reference spectra, and determining at least one of a polishing endpoint or an adjustment for a polishing rate based on the sequence of best matching reference spectra. Finding a best matching reference spectrum may include performing a cross-correlation of the measured spectrum with each of two or more of the plurality of reference spectra from the library and selecting a reference spectrum with the greatest correlation to the measured spectrum as a best matching reference spectrum. | 02-09-2012 |
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 |
20120096006 | BUILDING A LIBRARY OF SPECTRA FOR OPTICAL MONITORING - A method of controlling polishing includes storing a library having a plurality of reference spectra, polishing a substrate, measuring a sequence of spectra of light from the substrate during polishing, for each measured spectrum of the sequence of spectra, finding a best matching reference spectrum using a matching technique other than sum of squared differences to generate a sequence of best matching reference spectra, and determining at least one of a polishing endpoint or an adjustment for a polishing rate based on the sequence of best matching reference spectra. Finding a best matching reference spectrum may include performing a cross-correlation of the measured spectrum with each of two or more of the plurality of reference spectra from the library and selecting a reference spectrum with the greatest correlation to the measured spectrum as a best matching reference spectrum. | 04-19-2012 |
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 |
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 |
20120276815 | VARYING OPTICAL COEFFICIENTS TO GENERATE SPECTRA FOR POLISHING CONTROL - A method of generating a library of reference spectra includes storing an optical model for a layer stack having at a plurality of layers, receiving user input identifying a set of one or more refractive index functions and a set of one or more extinction coefficient functions a first layer from the plurality of layers, wherein the set of one or more refractive index functions includes a plurality of different refractive index functions or the set of one or more extinction coefficient functions includes a plurality of different extinction coefficient functions, and for each combination of a refractive index function from the set of refractive index functions and an extinction coefficient function from the set of extinction coefficient functions, calculating a reference spectrum using the optical model based on the refractive index function, the extinction coefficient function and a first thickness of the first layer. | 11-01-2012 |
20120278028 | GENERATING MODEL BASED SPECTRA LIBRARY FOR POLISHING - A method of generating a library of reference spectra, includes receiving a first spectrum representing a reflectance of a first stack of layers on a substrate, the first stack including a first dielectric layer, receiving a second spectrum representing a reflectance of a second stack layer on the substrate, the second stack including the first dielectric layer and a second dielectric layer that is not in the first stack, receiving user input identifying a plurality of different contribution percentages for at least one of the first stack or the second stack on the substrate, and for each contribution percentage from the plurality of different contribution percentages, calculating a reference spectrum from the first spectrum, the second spectrum and the contribution percentage. | 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 |
20130237128 | FITTING OF OPTICAL MODEL TO MEASURED SPECTRUM - A method of controlling a polishing operation includes polishing a first layer of a substrate, during polishing, obtaining a sequence over time of measured spectra with an in-situ optical monitoring system, for each measured spectrum from the sequence of measured spectra, fitting an optical model to the measured spectrum, the fitting including finding parameters that provide a minimum difference between an output spectrum of the optical model and the measured spectrum, the parameters including an endpoint parameter and at least one non-endpoint parameter, the fitting generating a sequence of fitted endpoint parameter values, each endpoint parameter value of the sequence associated with one of the spectra of the sequence of measured spectra, and determining at least one of a polishing endpoint or an adjustment of a pressure to the substrate from the sequence of fitted endpoint parameter values. | 09-12-2013 |
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 |
20130288572 | Linear Prediction For Filtering Of Data During In-Situ Monitoring Of Polishing - A method of controlling polishing includes polishing a substrate, during polishing monitoring the substrate with an in-situ monitoring system, the monitoring including generating a signal from a sensor, and filtering the signal to generate a filtered signal. The signal includes a sequence of measured values, and the filtered signal including a sequence of adjusted values. The filtering includes for each adjusted value in the sequence of adjusted values, generating at least one predicted value from the sequence of measured values using linear prediction, and calculating the adjusted value from the sequence of measured values and the predicted value. At least one of a polishing endpoint or an adjustment for a polishing rate is determined from the filtered signal. | 10-31-2013 |
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 |
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 |
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 |
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 |
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 |