Download or read book Dual domain Point Diffraction Interferometer written by and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A hybrid spatial/temporal-domain point diffraction interferometer (referred to as the dual-domain PS/PDI) that is capable of suppressing the scattered-reference-light noise that hinders the conventional PS/PDI is provided. The dual-domain PS/PDI combines the separate noise-suppression capabilities of the widely-used phase-shifting and Fourier-transform fringe pattern analysis methods. The dual-domain PS/PDI relies on both a more restrictive implementation of the image plane PS/PDI mask and a new analysis method to be applied to the interferograms generated and recorded by the modified PS/PDI. The more restrictive PS/PDI mask guarantees the elimination of spatial-frequency crosstalk between the signal and the scattered-light noise arising from scattered-reference-light interfering with the test beam. The new dual-domain analysis method is then used to eliminate scattered-light noise arising from both the scattered-reference-light interfering with the test beam and the scattered-reference-light interfering with the "true" pinhole-diffracted reference light. The dual-domain analysis method has also been demonstrated to provide performance enhancement when using the non-optimized standard PS/PDI design. The dual-domain PS/PDI is essentially a three-tiered filtering system composed of lowpass spatial-filtering the test-beam electric field using the more restrictive PS/PDI mask, bandpass spatial-filtering the individual interferogram irradiance frames making up the phase-shifting series, and bandpass temporal-filtering the phase-shifting series as a whole.
Download or read book Dual domain Lateral Shearing Interferometer written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The phase-shifting point diffraction interferometer (PS/PDI) was developed to address the problem of at-wavelength metrology of extreme ultraviolet (EUV) optical systems. Although extremely accurate, the fact that the PS/PDI is limited to use with coherent EUV sources, such as undulator radiation, is a drawback for its widespread use. An alternative to the PS/PDI, with relaxed coherence requirements, is lateral shearing interferometry (LSI). The use of a cross-grating, carrier-frequency configuration to characterize a large-field 4.times.-reduction EUV lithography optic is demonstrated. The results obtained are directly compared with PS/PDI measurements. A defocused implementation of the lateral shearing interferometer in which an image-plane filter allows both phase-shifting and Fourier wavefront recovery. The two wavefront recovery methods can be combined in a dual-domain technique providing suppression of noise added by self-interference of high-frequency components in the test-optic wavefront.
Download or read book EUV Lithography written by Vivek Bakshi and published by SPIE Press. This book was released on 2009 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt: Editorial Review Dr. Bakshi has compiled a thorough, clear reference text covering the important fields of EUV lithography for high-volume manufacturing. This book has resulted from his many years of experience in EUVL development and from teaching this subject to future specialists. The book proceeds from an historical perspective of EUV lithography, through source technology, optics, projection system design, mask, resist, and patterning performance, to cost of ownership. Each section contains worked examples, a comprehensive review of challenges, and relevant citations for those who wish to further investigate the subject matter. Dr. Bakshi succeeds in presenting sometimes unfamiliar material in a very clear manner. This book is also valuable as a teaching tool. It has become an instant classic and far surpasses others in the EUVL field. --Dr. Akira Endo, Chief Development Manager, Gigaphoton Inc. Description Extreme ultraviolet lithography (EUVL) is the principal lithography technology aiming to manufacture computer chips beyond the current 193-nm-based optical lithography, and recent progress has been made on several fronts: EUV light sources, optics, optics metrology, contamination control, masks and mask handling, and resists. This comprehensive volume is comprised of contributions from the world's leading EUVL researchers and provides all of the critical information needed by practitioners and those wanting an introduction to the field. Interest in EUVL technology continues to increase, and this volume provides the foundation required for understanding and applying this exciting technology. About the editor of EUV Lithography Dr. Vivek Bakshi previously served as a senior member of the technical staff at SEMATECH; he is now president of EUV Litho, Inc., in Austin, Texas.
Download or read book Null Test Fourier Domain Alignment Technique for Phase shifting Point Diffraction Interferometer written by and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Alignment technique for calibrating a phase-shifting point diffraction interferometer involves three independent steps where the first two steps independently align the image points and pinholes in rotation and separation to a fixed reference coordinate system, e.g, CCD. Once the two sub-elements have been properly aligned to the reference in two parameters (separation and orientation), the third step is to align the two sub-element coordinate systems to each other in the two remaining parameters (x, y) using standard methods of locating the pinholes relative to some easy to find reference point.
Download or read book Interferometric At wavelength Flare Characterization of EUV Optical Systems written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The extreme ultraviolet (EUV) phase-shifting point diffraction interferometer (PS/PDI) provides the high-accuracy wavefront characterization critical to the development of EUV lithography systems. Enhancing the implementation of the PS/PDI can significantly extend its spatial-frequency measurement bandwidth. The enhanced PS/PDI is capable of simultaneously characterizing both wavefront and flare. The enhanced technique employs a hybrid spatial/temporal-domain point diffraction interferometer (referred to as the dual-domain PS/PDI) that is capable of suppressing the scattered-reference-light noise that hinders the conventional PS/PDI. Using the dual-domain technique in combination with a flare-measurement-optimized mask and an iterative calculation process for removing flare contribution caused by higher order grating diffraction terms, the enhanced PS/PDI can be used to simultaneously measure both figure and flare in optical systems.
Download or read book Official Gazette of the United States Patent and Trademark Office written by United States. Patent and Trademark Office and published by . This book was released on 2001 with total page 1438 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Point Diffraction Interferometry written by Daodang Wang and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The point diffraction interferometer (PDI) employs a point-diffraction spherical wavefront as ideal measurement reference, and it overcomes the accuracy limitation of reference optics in traditional interferometers. To overcome the limitation of measurement range either with pinhole (low light transmission) or with single-mode fiber (low NA), a single-mode fiber with narrowed exit aperture has been proposed to obtain the point-diffraction wavefront with both high NA and high power. It is a key issue to analyze the point-diffraction wavefront error in PDI, which determines the achievable accuracy of the system. The FDTD method based on the vector diffraction theory provides a powerful tool for the design and optimization of the PDI system. In addition, a high-precision method based on shearing interferometry can be applied to measure point-diffraction wavefront with high NA, in which a double-step calibration including three-dimensional coordinate reconstruction and symmetric lateral displacement compensation is used to calibrate the geometric aberration. The PDI is expected to be a powerful tool for high-precision optical testing. With the PDI method, a high accuracy with RMS value better than subnanometer can be obtained in the optical surface testing and submicron in the absolute three-dimensional coordinate measurement, demonstrating the feasibility and wide application foreground of PDI.
Download or read book Selected Topics on Optical Fiber Technology written by Moh Yasin and published by IntechOpen. This book was released on 2012-02-22 with total page 682 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a comprehensive account of the recent advances and research in optical fiber technology. It covers a broad spectrum of topics in special areas of optical fiber technology. The book highlights the development of fiber lasers, optical fiber applications in medical, imaging, spectroscopy and measurement, new optical fibers and sensors. This is an essential reference for researchers working in optical fiber researches and for industrial users who need to be aware of current developments in fiber lasers, sensors and other optical fiber applications.
Download or read book Optical Interferometry written by Alexandr Banishev and published by BoD – Books on Demand. This book was released on 2017-02-15 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt: Optical methods of measurements are the most sensitive techniques of noncontact investigations, and at the same time, they are fast as well as accurate which increases reproducibility of observed results. In recent years, the importance of optical interferometry methods for research has dramatically increased, and applications range from precise surface testing to finding extrasolar planets. This book covers various aspects of optical interferometry including descriptions of novel apparatuses and methods, application interferometry for studying biological objects, surface qualities, materials characterization, and optical testing. The book includes a series of chapters in which experts share recent progress in interferometry through original research and literature reviews.
Download or read book Memorandum written by and published by . This book was released on 2000 with total page 632 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Optical Interferometry 2e written by P. Hariharan and published by Academic Press. This book was released on 2003-09-22 with total page 369 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanotechnology, sensor and measurement industries depend on these advances in optical interferometry for accuracy and profitability.
Download or read book Phase shifting Point diffraction Interferometry at EUV Wavelengths written by and published by . This book was released on 1997 with total page 2 pages. Available in PDF, EPUB and Kindle. Book excerpt: A novel phase-shifting point-diffraction interferometer (PS/PDI) operating at the Advanced Light Source (ALS) is being used to perform wavefront-measuring metrology at 13.4-nm wavelength to characterize aberrations in a multilayer-coated 10x Schwarzschild objective designed for extreme ultraviolet (EUV) projection lithography experiments. To achieve 0.1-micron critical dimension pattern transfer with EUV projection lithography at 13.4-nm wavelength, nearly diffraction-limited all-reflective multilayer-coated optical systems with 0.1 numerical aperture are required. The EUV wavefront, determined by the mirror surfaces and the reflective multilayer coatings, is measurable only at the operational wavelength of the system. The authors goal is to measure the EUV wavefront to an accuracy of 0.01 waves rms (0.13 nm). The PS/PDI is a type of point-diffraction interferometer, modified for significantly improved throughput and phase-shifting capability. The interferometer design utilizes a grating beamsplitter and pinhole spatial filters in the object and image planes of the optical system under test. The 10x-reduction Schwarzschild objective, with image-side numerical aperture of 0.08, is illuminated by a sub-micron pinhole in the object plane. A coarse, 20-micron pitch grating placed between the illumination pinhole and the Schwarzschild system serves a dual role as a small-angle beam-splitter and a phase-shifting element. The first-order diffracted beam from the grating is spatially filtered in the image plane of the Schwarzschild with a sub-100-nm pinhole and becomes the `D reference` wave in the interferometer. The zero-order beam is the `test` wave, and it passes unobstructed through a 4.5-[mu]m window in the image plane. The test and reference beams are separated by several microns in the image plane to minimize beam overlap. The interference fringes are recorded with a CCD detector placed about 12 cm from the Schwarzschild image plane.
Download or read book Hybrid Shearing and Phase shifting Point Diffraction Interferometer written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A new interferometry configuration combines the strengths of two existing interferometry methods, improving the quality and extending the dynamic range of both. On the same patterned mask, placed near the image-plane of an optical system under test, patterns for phase-shifting point diffraction interferometry and lateral shearing interferometry coexist. The former giving verifiable high accuracy for the measurement of nearly diffraction-limited optical systems. The latter enabling the measurement of optical systems with more than one wave of aberration in the system wavefront. The interferometry configuration is a hybrid shearing and point diffraction interferometer system for testing an optical element that is positioned along an optical path including: a source of electromagnetic energy in the optical path; a first beam splitter that is secured to a device that includes means for maneuvering the first beam splitter in a first position wherein the first beam splitter is in the optical path dividing light from the source into a reference beam and a test beam and in a second position wherein the first beam splitter is outside the optical path: a hybrid mask which includes a first section that defines a test window and at least one reference pinhole and a second section that defines a second beam splitter wherein the hybrid mask is secured to a device that includes means for maneuvering either the first section or the second section into the optical path positioned in an image plane that is created by the optical element, with the proviso that the first section of the hybrid mask is positioned in the optical path when first beam splitter is positioned in the optical path; and a detector positioned after the hybrid mask along the optical path.
Download or read book Extreme Ultraviolet EUV Holographic Metrology for Lithography Applications written by Sang-hun Yi and published by . This book was released on 2000 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Analysis of the Point diffraction Interferometer and Application to Testing of Pressure loaded Windows written by and published by . This book was released on 1980 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Polarization Phase shifting Point diffraction Interferometer PHD written by Robert Mark Neal and published by . This book was released on with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Liquid Crystal Point Diffraction Interferometer written by Carolyn Regan Mercer and published by . This book was released on 1995 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt:
