Abstract:
Transmissivity is restored to a gallium stained substrate by directing an electron beam to the substrate in the presence of an etching gas. For higher concentration of implanted gallium, the transparency can be substantially restored without reducing the thickness of the substrate. For lower doses of implanted gallium, the transmission is restored to 100% although the thickness of the substrate is reduced. The invention is suitable for use in the repair of photolitography masks.
Abstract:
Masks can be repaired by creating a structure that is different from the original design, but that produces the same aerial image. For example, missing opaque material can be replaced by implanting gallium atoms to reduce transmission and quartz can be etched to an appropriate depth to produce the proper phase. In another aspect, a laser or other means can be used to remove an area of a mask around a defect, and then mask structures, either the intended design structures or alternate structures that produce the same aerial image, can be constructed using charged particle beam deposition and etching. For example, an electron beam can be used to deposit quartz to alter the phase of transmitted light. An electron beam can also be used with a gas to etch quartz to remove a layer including implanted gallium atoms. Gallium staining can also be reduced or eliminated by providing a sacrificial layer that can be removed, along with the implanted gallium atoms, using, for example, a broad ion beam. In another aspect, a charged particle beam can be programmed to etch a defect using three-dimensional information derived from two charged particle beams images of the defect from different angle.
Abstract:
Methods and apparatus for calibration of a scanned beam system (8) are provided by sampling a calibration specimen (22) containing an array of targets with a spacing between samples that is greater than the spacing between targets in an array and forming an image from the samples to reduce calibration specimen degradation and to magnify calibration errors to enable very fine calibration of the scanned beam system (8).
Abstract:
Methods and apparatus for calibration of a scanned beam system (8) are provided by sampling a calibration specimen (22) containing an array of targets with a spacing between samples that is greater than the spacing between targets in an array and forming an image from the samples to reduce calibration specimen degradation and to magnify calibration errors to enable very fine calibration of the scanned beam system (8).
Abstract:
Methods and apparatus for calibration of a scanned beam system (8) are provided by sampling a calibration specimen (22) containing an array of targets with a spacing between samples that is greater than the spacing between targets in an array and forming an image from the samples to reduce calibration specimen degradation and to magnify calibration errors to enable very fine calibration of the scanned beam system (8).
Abstract:
Masks can be repaired by creating a structure that is different from the original design, but that produces the same aerial image. For example, missing opaque material can be replaced by implanting gallium atoms to reduce transmission and quartz can be etched to an appropriate depth to produce the proper phase. In another aspect, a laser or other means can be used to remove an area of a mask around a defect, and then mask structures, either the intended design structures or alternate structures that produce the same aerial image, can be constructed using charged particle beam deposition and etching. For example, an electron beam can be used to deposit quartz to alter the phase of transmitted light. An electron beam can also be used with a gas to etch quartz to remove a layer including implanted gallium atoms. Gallium staining can also be reduced or eliminated by providing a sacrificial layer that can be removed, along with the implanted gallium atoms, using, for example, a broad ion beam. In another aspect, a charged particle beam can be programmed to etch a defect using three-dimensional information derived from two charged particle beams images of the defect from different angle.
Abstract:
Topographical data from a scanning probe microscope (5Pm) or similar device is used as a substitute for endpoint detection to allow accurate repair of defects in phase shift photomasks using a charged particle beam system (210-216). The topographical data from a defect area is used to create a display of a semitransparent topographical map (217), which can be superimposed over a charged particle beam image (218-222). The density of the topographical image and the alignment of the two images can be adjusted by the operator in order to accurately position the beam (224). Topographical data from an SPM can also be used to adjust charged particle beam dose for each point within the defect area based upon the elevation and surface angle at the particular point (225-230). The charge particle beam is then used to repair the defect (s) (232-234).
Abstract:
Transmissivity is restored to a gallium stained substrate by directing an electron beam to the substrate in the presence of an etching gas. For higher concentration of implanted gallium, the transparency can be substantially restored without reducing the thickness of the substrate. For lower doses of implanted gallium, the transmission is restored to 100% although the thickness of the substrate is reduced. The invention is suitable for use in the repair of photolitography masks.
Abstract:
Topographical data from a scanning probe microscope or similar device is used as a substitute for endpoint detection to allow accurate repair of defects in phase shift photomasks using a charged particle beam system. The topographical data from a defect area is used to create a display of a semitransparent topographical map, which can be superimposed over a charged particle beam image. The density of the topographical image and the alignment of the two images can be adjusted by the operator in order to accurately position the beam. Topographical data from an SPM can also be used to adjust charged particle beam dose for each point within the defect area based upon the elevation and surface angle at the particular point.
Abstract:
Masks can be repaired by creating a structure that is different from the original design, but that produces the same aerial image. For example, missing opaque material can be replaced by implanting gallium atoms to reduce transmission and quartz can be etched to an appropriate depth to produce the proper phase. In another aspect, a laser or other means can be used to remove an area of a mask around a defect, and then mask structures, either the intended design structures or alternate structures that produce the same aerial image, can be constructed using charged particle beam deposition and etching. For example, an electron beam can be used to deposit quartz to alter the phase of transmitted light. An electron beam can also be used with a gas to etch quartz to remove a layer including implanted gallium atoms. Gallium staining can also be reduced or eliminated by providing a sacrificial layer that can be removed, along with the implanted gallium atoms, using, for example, a broad ion beam. In another aspect, a charged particle beam can be programmed to etch a defect using three-dimensional information derived from two charged particle beams images of the defect from different angle.