Abstract: The present invention includes an exposure chamber configured to contain a passivating gas having a selected hydrogen concentration, the exposure chamber further configured to contain at least one NLO crystal for exposure to the passivating gas within the chamber, a passivating gas source fluidically connected to the exposure chamber, the passivating gas source configured to supply passivating gas to an interior portion of the exposure chamber, and a substrate configured to hold the NLO crystal within the chamber, the substrate further configured to maintain a temperature of the NLO crystal at or near a selected temperature, the selected temperature being below a melting temperature of the NLO crystal.

Abstract: An improved solid-state laser for generating 193 nm light is described. This laser uses the 6th harmonic of a fundamental wavelength near 1160 nm to generate the 193 nm light. The laser mixes the 1160 nm fundamental wavelength with the 5th harmonic, which is at a wavelength of approximately 232 nm. By proper selection of non-linear media, such mixing can be achieved by nearly non-critical phase matching. This mixing results in high conversion efficiency, good stability, and high reliability.

Abstract: Optimization of optical parametric models for structural analysis using optical critical dimension metrology is described. A method includes determining a first optical model fit for a parameter of a structure. The first optical model fit is based on a domain of quantities for a first model of the structure. A first near optical field response is determined for a first quantity of the domain of quantities and a second near optical field response is determined for a second, different quantity of the domain of quantities. The first and second near optical field responses are compared to locate a common region of high optical field intensity for the parameter of the structure. The first model of the structure is modified to provide a second, different model of the structure. A second, different optical model fit is determined for the parameter of the structure based on the second model of the structure.

Abstract: A pulse multiplier includes a polarizing beam splitter, a wave plate, and a set of mirrors. The polarizing beam splitter receives an input laser pulse. The wave plate receives light from the polarized beam splitter and generates a first set of pulses and a second set of pulses. The first set of pulses has a different polarization than the second set of pulses. The polarizing beam splitter, the wave plate, and the set of mirrors create a ring cavity. The polarizing beam splitter transmits the first set of pulses as an output of the pulse multiplier and reflects the second set of pulses into the ring cavity. This pulse multiplier can inexpensively reduce the peak power per pulse while increasing the number of pulses per second with minimal total power loss.

Abstract: A cell for a vacuum ultraviolet plasma light source, the cell having a closed sapphire tube containing at least one noble gas. Such a cell does not have a metal housing, metal-to-metal seals, or any other metal flanges or components, except for the electrodes (in some embodiments). In this manner, the cell is kept to a relatively small size, and exhibits a more uniform heating of the gas and cell than can be readily achieved with a hybridized metal/window cell design. These designs generally result in higher plasma temperatures (a brighter light source), shorter wavelength output, and lower optical noise due to fewer gas convection currents created between the hotter plasma regions and surrounding colder gases. These cells provide a greater amount of output with wavelengths in the vacuum ultraviolet range than do quartz or fused silica cells. These cells also produce continuous spectral emission well into the infrared range, making them a broadband light source.

Abstract: A system for inspecting a specimen is provided. The system includes an illumination subsystem configured to produce a plurality of channels of light energy, each channel of light energy produced having differing characteristics (type, wavelength, etc.) from at least one other channel of light energy. Optics are configured to receive the plurality of channels of light energy and combine them into a spatially separated combined light energy beam and direct it toward the specimen. A data acquisition subsystem comprising at least one detector is provided, configured to separate reflected light energy into a plurality of received channels corresponding to the plurality of channels of light energy and detect the received channels.

Abstract: A method and apparatus for propagating charge through a sensor and implementation thereof is provided. The method and apparatus may be used to inspect specimens, the sensor operating to advance an accumulated charge between gates of the TDI sensor. The design implementation provides a set of values representing a plurality of out of phase signals, such as sinusoidal or trapezoidal signals. These out of phase signals are converted and transmitted to the sensor. The converted signals cause the sensor to transfer charges in the sensor toward an end of the sensor. Aspects such as feed through correction and correction of nonlinearities are addressed.

Abstract: Inspection of EUV patterned masks, blank masks, and patterned wafers generated by EUV patterned masks requires high magnification and a large field of view at the image plane. An EUV inspection system can include a light source directed to an inspected surface, a detector for detecting light deflected from the inspected surface, and an optic configuration for directing the light from the inspected surface to the detector. In particular, the detector can include a plurality of sensor modules. Additionally, the optic configuration can include a plurality of mirrors that provide magnification of at least 100× within an optical path less than 5 meters long. In one embodiment, the optical path is approximately 2-3 meters long.

Abstract: A laser illuminator for use in an inspection system, such as a semiconductor wafer inspection system or photomask inspection system is provided. The gain medium in the illuminator comprises optical fiber, and amplification, beam splitting, frequency and/or bandwidth conversion, peak power reduction, and q-switching or mode locking may be employed. Certain constructs including doped fiber, gratings, saturable absorbers, and laser diodes are disclosed to provide enhanced illumination.

Abstract: An improved inspection system using back-side illuminated linear sensing for propagating charge through a sensor is provided. Focusing optics may be used with a back side illuminated linear sensor to inspect specimens, the back side illuminated linear sensor operating to advance an accumulated charge from one side of each pixel to the other side. The design comprises controlling voltage profiles across pixel gates from one side to the other side in order to advance charge between to a charge accumulation region. Controlling voltage profiles comprises attaching a continuous polysilicon gate across each pixel within a back side illuminated linear sensor array. Polysilicon gates and voltages applied thereto enable efficient electron advancement using a controlled voltage profile.

Abstract: A relatively high NA objective employed for use in imaging a specimen is provided. The objective includes a lens group having at least one focusing lens configured to receive light energy and form an intermediate image, at least one field lens oriented to receive the intermediate image and provide intermediate light energy, and a Mangin mirror arrangement positioned to receive the intermediate light energy and apply light energy to the specimen. One or more elements may employ an aspheric surface. The objective may provide an uncorrected spectral bandwidth up to approximately 193 to 266 nanometers and numerical apertures in excess of 0.9. Elements are less than 100 millimeters in diameter and may fit within a standard microscope. The field lens may include more than one lens and may be formed of a material different from at least one other lens in the objective.

Abstract: A method and apparatus for inspecting a specimen are provided. The apparatus comprises a primary illumination source, a catadioptric objective exhibiting central obscuration that directs light energy received from the primary illumination source at a substantially normal angle toward the specimen, and an optical device, such as a prism or reflective surface, positioned within the central obscuration resulting from the catadioptric objective for receiving further illumination from a secondary illumination source and diverting the further illumination to the specimen. The method comprises illuminating a surface of the specimen at a variety of angles using a primary illumination source, illuminating the surface using a secondary illumination source, the illuminating by the secondary illumination source occurring at a substantially normal angle of incidence; and imaging all reflected, scattered, and diffracted light energy received from the surface onto a detector.

Abstract: An ultra-broadband ultraviolet (UV) catadioptric imaging microscope system with wide-range zoom capability. The microscope system, which includes a catadioptric lens group and a zooming tube lens group, has high optical resolution in the deep UV wavelengths, continuously adjustable magnification, and a high numerical aperture. The system integrates microscope modules such as objectives, tube lenses and zoom optics to reduce the number of components, and to simplify the system manufacturing process. The preferred embodiment offers excellent image quality across a very broad deep ultraviolet spectral range, combined with an all-refractive zooming tube lens. The zooming tube lens is modified to compensate for higher-order chromatic aberrations that would normally limit performance.

Abstract: An inspection system for inspecting a surface of a wafer/mask/reticle can include a modular array. The modular array can include a plurality of time delay integration (TDI) sensor modules, each TDI sensor module having a TDI sensor and a plurality of localized circuits for driving and processing the TDI sensor. At least one of the localized circuits can control a clock associated with the TDI sensor. At least one light pipe can be used to distribute a source illumination to the plurality of TDI sensor modules. The plurality of TDI sensor modules can be positioned capture a same inspection region or different inspection regions. The plurality of TDI sensor modules can be identical or provide for different integration stages. Spacing of the modules can be arranged to provide 100% coverage of the inspection region in one pass or for fractional coverage requiring two or more passes for complete coverage.

Abstract: A system and method for inspecting a specimen, such as a semiconductor wafer, including illuminating at least a portion of the specimen using an excimer source using at least one relatively intense wavelength from the source, detecting radiation received from the illuminated portion of the specimen, analyzing the detected radiation for potential defects present in the specimen portion.

Abstract: A reduced size catadioptric objective and system is disclosed. The objective may be employed with light energy having a wavelength in the range of approximately 190 nanometers through the infrared light range. Elements are less than 100 mm in diameter. The objective comprises a focusing lens group configured to receive the light energy, at least one field lens oriented to receive focused light energy from the focusing lens group and provide intermediate light energy, and a Mangin mirror arrangement positioned to receive the intermediate light energy from the field lens and form controlled light energy for transmission to a specimen. The Mangin mirror arrangement imparts controlled light energy with a numerical aperture in excess of 0.65 and up to approximately 0.90, and the design may be employed in various environments.

Abstract: A relatively high spectral bandwidth objective employed for use in imaging a specimen and method for imaging a specimen is provided. The objective includes a lens group having at least one focusing lens configured to receive light energy and form an intermediate image, at least one field lens oriented to receive the intermediate image and provide intermediate light energy, and a Mangin mirror arrangement positioned to receive the intermediate light energy and apply light energy to the specimen. The objective may provide, in certain instances, a spectral bandwidth up to approximately 193 to 266 nanometers and can provide numerical apertures in excess of 0.9. Elements are less than 100 millimeters in diameter and may fit within a standard microscope. The field lens may include more than one lens and may be formed of a material different from at least one other lens in the objective.

Abstract: A relatively high spectral bandwidth objective employed for use in imaging a specimen and method for imaging a specimen is provided. The objective includes a lens group having at least one focusing lens configured to receive light energy and form focused light energy. The focused light energy forms an intermediate image. The objective further includes at least one field lens located in proximity to an intermediate image, and a catadioptric arrangement positioned to receive the intermediate light energy from the at and form controlled light energy. The catadioptric arrangement may include at least one Mangin element and can include a meniscus lens element.

Abstract: A system for use with a reduced size catadioptric objective is disclosed. The system including the reduced size objective includes various subsystems to allow enhanced imaging, the subsystems including illumination, imaging, autofocus, positioning, sensor, data acquisition, and data analysis. The objective may be employed with light energy having a wavelength in the range of approximately 190 nanometers through the infrared light range, and elements of the objective are less than 100 mm in diameter. The objective comprises a focusing lens group and at least one field lens oriented to receive focused light energy from the focusing lens group and provide intermediate light energy. The objective also includes a Mangin mirror arrangement. The design imparts controlled light energy with a numerical aperture in excess of 0.65 and up to approximately 0.90 to a specimen for imaging purposes, and the design may be employed in various environments.

Abstract: A reduced size catadioptric inspection system employing a catadioptric objective and immersion substance is disclosed. The objective may be employed with light energy having a wavelength in the range of approximately 190 nanometers through the infrared light range, and can provide numerical apertures in excess of 0.9. Elements are less than 100 millimeters in diameter and may fit within a standard microscope. The objective comprises a focusing lens group, a field lens, a Mangin mirror arrangement, and an immersion substance or liquid between the Mangin mirror arrangement and the specimen. A variable focal length optical system for use with the objective in the catadioptric inspection system is also disclosed.