| Class / Patent application number | Description | Number of patent applications / Date published |
|---|
| 355056000 | Automatic or semiautomatic focusing when varying image size | 9 |
| 20090103068 | EXPOSURE APPARATUS AND METHOD FOR PHOTOLITHOGRAPHY PROCESS - Provided is an exposure apparatus including a variable focusing device. The variable focusing device may include a transparent membrane that may be deformed in the presence of an electric field. The deformation of the transparent membrane may allow the focus length of a radiation beam to be modified. In an embodiment, the variable focusing device may be modulated such that a radiation beam having a first focus length is provided for a first position on an exposure target and a radiation beam having a second focus length is provided for a second position on the exposure target. A method and computer-readable medium are also provided. | 04-23-2009 |
| 20110181856 | Auto-focusing device and method for maskless exposure apparatus - Example embodiments are directed to an auto-focusing device for use in a maskless exposure apparatus that performs a beam focus calibration and an auto-focusing method using the same. The auto-focusing device includes a projection optical unit, a focus calibration unit, and a controller. The projection optical unit includes a distance measurement sensor and a focus controller that generate a beam of light. The focus calibration unit includes a substrate having a reference mark on which the beam generated from the projection optical unit is illuminated, a measuring optical unit configured to obtain image information of the beam illuminated on the reference mark, and a stage configured to support the substrate and the measuring optical unit. The controller is configured to control the focus controller so that a beam of the beam generated from the measuring optical unit is located on the surface of an exposed member. | 07-28-2011 |
| 20130083305 | METHOD, OPTICAL MODULE AND AUTO-FOCUSING SYSTEM FOR WAFER EDGE EXPOSURE - Embodiments relate to a method, optical module and auto-focusing system for wafer edge exposure. The optical module comprises a light source emitting light of a wavelength to expose a photoresist, an exposing optics and a mask with an aperture between the light source and the exposing optics. The light emitted from the light source passes through the mask and then reaches the exposing optics to image the aperture on the wafer edge covered with the photoresist to form a focused light spot. The positions of the light source, the mask and the exposing optics, and the size of the aperture are configured such that the optical axis of the incident light is perpendicular to the wafer surface, and the light spot completely covers the wafer edge in the radial direction of the wafer. | 04-04-2013 |
| 20140036245 | APPARATUS AND METHODS FOR REDUCING AUTOFOCUS ERROR - In a lithography tool used in fabricating microelectronic devices, autofocus (AF) systems provide automatic image focusing before making exposures. To reduce production of erroneous results based on interaction of a beam of AF light with certain regions on lithographic substrates, a subject AF device has a sending unit and a receiving unit. The sending unit directs an AF light beam to the substrate, and the receiving unit receives AF light reflected from the substrate. The receiving unit has a system photodetector and a patterned optical element that receives AF light from the substrate and transmits a selected diffraction order(s) of said light. The system photodetector senses light of the selected diffraction order of reflected AF light while at least one additional photodetector detects divergent reflected AF light. Substrate areas exhibiting unusual amounts of divergent light may indicate a focus-error condition. The AF systems can be configured as fringe-projection or slit-projection AF systems. | 02-06-2014 |
| 20140049761 | DESIGN RULES FOR REDUCING THE SENSITIVITY OF FRINGE PROJECTION AUTOFOCUS TO AIR TEMPERATURE CHANGES - Fringe projection autofocus systems are provided with variable pitch diffraction gratings or multiple diffraction gratings so that a reference beam and a measurement beam propagate along a common path. Alternatively, an input beam can be directed to a diffraction grating so that the selected diffraction orders propagate along a common path. In some examples, distinct spectral bands are used for reference and measurement beams. | 02-20-2014 |
| 20140300879 | FLUID EXTRACTION SYSTEM, LITHOGRAPHIC APPARATUS AND DEVICE MANUFACTURING METHOD - An immersion lithographic apparatus typically includes a fluid handling system. The fluid handling system generally has a two-phase fluid extraction system configured to remove a mixture of gas and liquid from a given location. Because the extraction fluid comprises two phases, the pressure in the extraction system can vary. This pressure variation can be passed through the immersion liquid and cause inaccuracy in the exposure. To reduce the pressure fluctuation in the extraction system, a buffer chamber may be used. This buffer chamber may be connected to the fluid extraction system in order to provide a volume of gas which reduces pressure fluctuation. Alternatively or additionally, a flexible wall may be provided somewhere in the fluid extraction system. The flexible wall may change shape in response to a pressure change in the fluid extraction system. By changing shape, the flexible wall can help to reduce, or eliminate, the pressure fluctuation. | 10-09-2014 |
| 20150070670 | CORRECTION OF ERRORS CAUSED BY AMBIENT NON-UNIFORMITIES IN A FRINGE-PROJECTION AUTOFOCUS SYSTEM IN ABSENCE OF A REFERENCE MIRROR - Fringe-projection autofocus system devoid of a reference mirror. Contributions to error in determination of a target surface profile caused by air non-uniformities measured based on multiple measurements of the target surface performed at different wavelengths, and/or angles of incidence, and/or grating pitches and subtracted from the measured profile, rendering the system substantially insensitive to presence of air turbulence. Same optical beams forming a fringe irradiance pattern on target surface are used for measurement of the surface profile and reduction of measurement error by the amount attributed to air turbulence. | 03-12-2015 |
| 20180024448 | FOCUS CENTERING METHOD FOR DIGITAL LITHOGRAPHY | 01-25-2018 |
| 355057000 | Reflector between original and photo-sensitive paper | 1 |
| 20130038848 | OPTICAL DEVICES HAVING KINEMATIC COMPONENTS - Optical devices that have at least one optical element and a plurality of kinematic components are disclosed. The number m of the kinematic components of one type exceed the number n of degrees of freedom in which the optical element can be manipulated. At least one of the n degrees of freedom can be x-displacement, y-displacement, z-displacement or tilt. | 02-14-2013 |
