Prof. Roger H. French Profile

Prof. Roger H. French

Kyocera Professor at Case Western Reserve Univ

SPIE Involvement:

Author

Publications (42)

Proceedings Article | 18 September 2018 Presentation

Degradation analysis of polyamide-based backsheets in field photovoltaic modules under different climatic conditions (Conference Presentation)

Yadong Lyu, Andrew Fairbrother, Jae Hyun Kim, Xiaohong Gu, Michael Kempe, Liang Ji, Kent Whitfield, Kenneth Boyce, Adam Hauser, Greg O’Brien, Scott Julien, Kai-Tak Wan, Yu Wang, Laura Bruckman, Roger French

Proceedings Volume 10759, 107590F (2018) https://doi.org/10.1117/12.2325843

KEYWORDS: Climatology, Climate change, Solar cells, Oceanography, Spectroscopy

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Proceedings Article | 23 August 2017 Paper

Degradation of photovoltaic backsheet materials under multi-factor accelerated UV light exposures

Addison Klinke, Abdulkerim Gok, Roger French, Laura Bruckman, Silas Ifeanyi

Proceedings Volume 10370, 1037004 (2017) https://doi.org/10.1117/12.2274108

KEYWORDS: Solar cells, Ultraviolet radiation, Humidity, Statistical modeling, FT-IR spectroscopy, Absorbance, Infrared spectroscopy, Polymers, Analytics, Photovoltaics

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Proceedings Article | 23 August 2017 Paper

Characterizing the weathering induced changes in optical performance and properties of poly(ethylene-terephthalate) via MaPd:RTS spectroscopy

Devin Gordon, Lin DeNoyer, Corey Meyer, Noah Sweet, David Burns, Laura Bruckman, Roger French

Proceedings Volume 10370, 1037005 (2017) https://doi.org/10.1117/12.2274113

KEYWORDS: Positron emission tomography, Ultraviolet radiation, Light scattering, Spectroscopy, Solar cells, UV optics, Reflection, Refraction, Optical properties, Air contamination

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Proceedings Article | 23 August 2017 Paper

Model development of degradation of PV modules backsheet with locating place of module

Yu Wang, Sebastien Merzlic, Andrew Fairbrother, Lucas Fridman, Scott Julien, Amy Lefebvre, Xiaohong Gu, Liang Ji, Kenneth Boyce, Michael Kempe, Kai-tak Wan, Roger French, Laura Bruckman, Camille Loyer, Gregory O'Brien

Proceedings Volume 10370, 103700L (2017) https://doi.org/10.1117/12.2274209

KEYWORDS: Solar cells, Climatology, FT-IR spectroscopy, Photovoltaics, Humidity, Positron emission tomography, Spectroscopy

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Proceedings Article | 23 August 2017 Paper

Degradation analysis of field-exposed photovoltaic modules with non-fluoropolymer-based backsheets

Kenneth Boyce, Sebastien Merzlic, Andrew Fairbrother, Xiaohong Gu, Scott Julien, Kai-Tak Wan, Liang Ji, Amy Lefebvre, Greg O'Brien, Yu Wang, Laura Bruckman, Roger French, Michael Kempe

Proceedings Volume 10370, 1037003 (2017) https://doi.org/10.1117/12.2272488

KEYWORDS: Photovoltaics, Solar cells, Polymers, Reliability, Optical inspection, Colorimetry, Raman spectroscopy, Infrared spectroscopy

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The selection of polymeric materials utilized in photovoltaic (PV) modules has changed relatively little since the inception of the PV industry, with ethylene-vinyl acetate (EVA), polyethylene terephthalate (PET), and fluoropolymer-based laminates being the most widely adopted primary components of the encapsulant and backsheet materials. The backsheet must serve to electrically insulate the solar cells and protect them from the effects of weathering. Due to continued downward pressure on cost, other polymeric materials are being formulated to withstand outdoor exposure for use in backsheets to replace either the PET film, the fluoropoymer film, or both. Because of their relatively recent deployment, less is known about their reliability and if they are durable enough to fulfill the ≥25 year warranties of current PV modules. This work presents a degradation analysis of field-exposed modules with polyamide- and polyester-based backsheets. Modules were exposed for up to five years in different geographic locations: USA (Maryland, Ohio), China, and Italy. Surface and cross-sectional analysis included visual inspection, colorimetry, glossimetry, and Fourier-transform infrared spectroscopy. Each module experienced different types of degradation depending on the exposure site, even for the same material and module brand. For instance, the polyamide-based backsheet experienced hairline cracking and greater yellowing and chemical changes in China (Changsu, humid subtropical climate), while in Italy (Rome, hot-summer Mediterranean climate) it underwent macroscopic cracking and greater losses in gloss. Spectroscopic studies have permitted identification of degradation products and changes in polymer structure over time. Comparisons are made to fielded modules with fluoropolymer-based backsheets, as well as backsheet materials in accelerated laboratory exposures. Implications for qualification testing and service life prediction of the non-fluoropolymer-based backsheets are discussed.

Proceedings Article | 2 November 2016 Presentation

Cross-correlation of backsheet degradation between real-world exposed modules and accelerated exposures of backsheet materials (Conference Presentation)

Laura Bruckman, Roger French, Michael Kempe, Amy Lefebvre, Yu Wang, Xiaohong Gu, Liang Ji, Kai-Tak Wan, Christopher Flueckiger

Proceedings Volume 9938, 993805 (2016) https://doi.org/10.1117/12.2238162

KEYWORDS: Data modeling, Solar cells, Atmospheric modeling, Climatology, Performance modeling, Polymers, Meteorology, Data acquisition, Feature selection, Nondestructive evaluation

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Proceedings Article | 26 September 2016 Presentation + Paper

Characterizing the weathering induced haze formation and gloss loss of poly(ethylene-terephthalate) via MaPd:RTS spectroscopy

Devin Gordon, Corey Meyer, Noah Sweet, Laura Bruckman, Roger French, Lin DeNoyer, Cara Fagerholm, Abdulkerim Gok

Proceedings Volume 9938, 99380I (2016) https://doi.org/10.1117/12.2238295

KEYWORDS: Positron emission tomography, Air contamination, Spectroscopy, Ultraviolet radiation, Optical properties, Scattering, Refraction, Data modeling, Light scattering, Statistical modeling

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Proceedings Article | 23 September 2015 Paper

A data science approach to understanding photovoltaic module degradation

Nikhil Goel, Cara Fagerholm, Christopher Alcantara, Nicholas Wheeler, Abdulkerim Gok, Timothy Peshek, Laura Bruckman, Davis Zabiyaka, Mason Terry, Thomas Dang, Roger French

Proceedings Volume 9563, 95630L (2015) https://doi.org/10.1117/12.2209204

KEYWORDS: Solar cells, Confocal microscopy, Photovoltaics, Electroluminescence, Positron emission tomography, Raman spectroscopy, Microscopy, Data modeling, Diagnostics, Corrosion

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Proceedings Article | 8 October 2014 Paper

Optical properties of PV backsheets: key indicators of module performance and durability

William Gambogi, Thomas Felder, James Kopchick, Alexander Bradley, Babak Hamzavytehrany, T. John Trout, R. Scott Peacock, Katherine Stika, Abdulkerim Gok, Roger French, Oakland Fu, Hongjie Hu

Proceedings Volume 9179, 91790P (2014) https://doi.org/10.1117/12.2062063

KEYWORDS: Optical properties, Solar cells, FT-IR spectroscopy, Ultraviolet radiation, Positron emission tomography, Spectroscopy, Chemical analysis, Photovoltaics, Polymers, Oxidation

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Proceedings Article | 8 October 2014 Paper

Thermal performance of microinverters on dual-axis trackers

Mohammad Hossain, Timothy Peshek, Yifan Xu, Liang Ji, Alexis Abramson, Roger French, Jiayang Sun

Proceedings Volume 9179, 91790J (2014) https://doi.org/10.1117/12.2061235

KEYWORDS: Solar cells, Photovoltaics, Temperature metrology, Capacitors, Data analysis, Reliability, Statistical analysis, Data modeling, Field effect transistors, Thermal modeling

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Proceedings Article | 24 September 2013 Paper

Photovoltaic lifetime and degradation science statistical pathway development: acrylic degradation

Ian Kidd, Laura Bruckman, Nicholas Wheeler, Jiayang Sun, Roger French

Proceedings Volume 8825, 88250D (2013) https://doi.org/10.1117/12.2024717

KEYWORDS: Photovoltaics, Analytics, Ultraviolet radiation, Absorption, Polymethylmethacrylate, Solar cells, Statistical analysis, Absorbance, Solar concentrators, Standards development

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Proceedings Article | 24 September 2013 Paper

Degradation of transparent conductive oxides: mechanistic insights across configurations and exposures

Heather Lemire, Kelly Peterson, Ina Martin, Kenneth Singer, Roger French, Samuel Sprawls

Proceedings Volume 8825, 882502 (2013) https://doi.org/10.1117/12.2024691

KEYWORDS: Transparent conductors, Air contamination, Oxides, Photovoltaics, Solar energy, Sun, Solar cells, Tin, Humidity, Optical properties

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Proceedings Article | 25 March 2013 Paper

GaN microdomes for broadband omnidirectional antireflection for concentrator photovoltaics

Ian Kidd, Roger French, Hongping Zhao, Matthew McGoogan, Tyler Piedimonte, Lu Han

Proceedings Volume 8620, 862016 (2013) https://doi.org/10.1117/12.2002864

KEYWORDS: Gallium nitride, Reflectivity, Silica, Reflection, Antireflective coatings, Polarization, Photovoltaics, Etching, Finite-difference time-domain method, Reactive ion etching

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SPIE Journal Paper | 19 November 2012

Photodegradation in a stress and response framework: poly(methyl methacrylate) for solar mirrors and lens

Myles Murray, Laura Bruckman, Roger French

JPE, Vol. 2, Issue 1, 022004, (November 2012) https://doi.org/10.1117/12.10.1117/1.JPE.2.022004

KEYWORDS: Ultraviolet radiation, Polymethylmethacrylate, Photovoltaics, Absorbance, Solar energy, Solar radiation, Mirrors, Absorption, Lamps, Solar cells

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Proceedings Article | 16 October 2012 Paper

Degradation of back surface acrylic mirrors for low concentration and mirror-augmented photovoltaics

Devin Gordon, Mark Schuetz, Greg Reinbolt, Myles Murray, Roger French, Samuel Richardson, Laura Bruckman

Proceedings Volume 8472, 847205 (2012) https://doi.org/10.1117/12.930102

KEYWORDS: Mirrors, Ultraviolet radiation, Photovoltaics, Scattering, Reflectivity, Humidity, Light scattering, Corrosion, Optical transfer functions, Aluminum

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Proceedings Article | 19 September 2011 Paper

Design and performance of a low-cost acrylic reflector for a ~7x concentrating photovoltaic module

Roger French, Kara Shell, Mark Schuetz, Scott Brown, Robert Davis

Proceedings Volume 8108, 81080A (2011) https://doi.org/10.1117/12.897763

KEYWORDS: Compound parabolic concentrators, Mirrors, Prototyping, Reflectors, Ray tracing, Reflectivity, Aluminum, Receivers, Ultraviolet radiation, Silver

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Proceedings Article | 13 September 2011 Paper

Solar radiation durability framework applied to acrylic solar mirrors

Wei-Chun Lin, Jim Elman, Kara Shell, Scott Brown, Devin Gordon, Mark Schuetz, Sean Fowler, Roger French, Myles Murray

Proceedings Volume 8112, 811203 (2011) https://doi.org/10.1117/12.893827

KEYWORDS: Mirrors, Ultraviolet radiation, Photovoltaics, Polymethylmethacrylate, Solar cells, Solar radiation, Absorbance, Polymers, Neodymium, Optical properties

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SPIE Journal Paper | 1 July 2009

Fluid-photoresist interactions and imaging in high-index immersion lithography

Hoang Tran, Eric Hendrickx, Frieda Van Roey, Geert Vandenberghe, Roger French

JM3, Vol. 8, Issue 03, 033006, (July 2009) https://doi.org/10.1117/12.10.1117/1.3224950

KEYWORDS: Microfluidics, Water, Microfluidic imaging, Semiconducting wafers, Immersion lithography, Crystals, Liquids, Quartz, Printing, Lithography

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SPIE Journal Paper | 1 April 2009

Index of refraction of high-index lithographic immersion fluids and its variability

Min Yang, Simon Kaplan, Roger French, John Burnett

JM3, Vol. 8, Issue 02, 023005, (April 2009) https://doi.org/10.1117/12.10.1117/1.3124189

KEYWORDS: Refraction, Water, Refractive index, Prisms, Thermal optics, Lithography, Microfluidics, Absorbance, Temperature metrology, Immersion lithography

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SPIE Journal Paper | 1 July 2008

Optical properties of Teflon^® AF amorphous fluoropolymers

Min Yang, Roger French, Edward Tokarsky

JM3, Vol. 7, Issue 03, 033010, (July 2008) https://doi.org/10.1117/12.10.1117/1.2965541

KEYWORDS: Atrial fibrillation, Absorption, Absorbance, Optical properties, Refractive index, Refraction, Polymers, Silicon, Data modeling, Silicon films

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Proceedings Article | 12 March 2008 Paper

High-index immersion fluids enabling cost-effective single-exposure lithography for 32 nm half pitches

Rebekah Derryberry, Adam Bernfeld, Michael Mocella, Freida Van Roey, Roger French, Hoang Tran, Doug Adelman, Eric Hendrickx, Charles Chen, Mureo Kaku, Nyrissa Rogado

Proceedings Volume 6924, 692417 (2008) https://doi.org/10.1117/12.772105

KEYWORDS: Semiconducting wafers, Absorbance, Silicon, Water, Microfluidics, Lithography, Liquids, Contamination, Double patterning technology, Extreme ultraviolet

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Proceedings Article | 26 March 2007 Paper

High-index immersion lithography with second-generation immersion fluids to enable numerical aperatures of 1.55 for cost effective 32-nm half pitches

J. Feldman, C. Chen, M. Lemon, B. Fones, D. Adelman, K. Krohn, L. Brubaker, M. Yang, H. Tran, A. Shoe, O. Nagao, S. McLain, R. French, M. Kaku, R. Wheland, M. Mocella, V. Liberman, B. Fischel, W. Qiu, D. Hardy

Proceedings Volume 6520, 65201O (2007) https://doi.org/10.1117/12.712234

KEYWORDS: Water, Absorbance, Microfluidics, Refractive index, Immersion lithography, Diffractive optical elements, Contamination, Scanners, Computational fluid dynamics, Absorption

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Proceedings Article | 15 March 2006 Paper

Second generation fluids for 193nm immersion lithography

Doug Adelman, Min Yang, Aaron Shoe, Hoang Tran, Steve McLain, Jerald Feldman, Michael Lemon, Sheng Peng, Michael Crawford, Roger French, Weiming Qiu, Robert Wheland

Proceedings Volume 6154, 615415 (2006) https://doi.org/10.1117/12.656626

KEYWORDS: Microfluidics, Refractive index, Immersion lithography, Microfluidic imaging, Water, Absorbance, Transparency, Lithography, 193nm lithography, Optical lithography

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SPIE Journal Paper | 1 July 2005

Imaging of 32-nm 1:1 lines and spaces using 193-nm immersion interference lithography with second-generation immersion fluids to achieve a numerical aperture of 1.5 and a k₁ of 0.25

Roger French, Harry Sewell, Min Yang, Sheng Peng, Diane McCafferty, Weiming Qiu, Robert Wheland, Michael Lemon, Louis Markoya, Michael Crawford

JM3, Vol. 4, Issue 03, 031103, (July 2005) https://doi.org/10.1117/12.10.1117/1.2039953

KEYWORDS: Refractive index, Water, Oscillators, Absorption, Absorbance, Lithography, Immersion lithography, Microfluidics, Microfluidic imaging, Glasses

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Proceedings Article | 12 May 2005 Paper

Second generation fluids for 193 nm immersion lithography

Michael Lemon, Robert Wheland, Sheng Peng, Michael Crawford, Roger French, Min Yang, Weiming Qiu

Proceedings Volume 5754, (2005) https://doi.org/10.1117/12.606448

KEYWORDS: Water, Oscillators, Refraction, Absorption, Absorbance, Microfluidics, Immersion lithography, Optical lithography, Lithography, Microfluidic imaging

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Proceedings Article | 28 May 2004 Paper

157-nm pellicles for photolithography: mechanistic investigation of the deep-UV photolysis of fluorocarbons

Robert Wheland, Steffen Jockusch, Nicholas Turro, Paul Zimmerman, Michael Lemon, Tatjana Widerschpan, Andre Braun, Kwangjoo Lee, Roger French

Proceedings Volume 5377, (2004) https://doi.org/10.1117/12.534381

KEYWORDS: Fluorine, Photolysis, Pellicles, Ultraviolet radiation, FT-IR spectroscopy, Liquids, Polymers, Oxygen, Deep ultraviolet, Optical lithography

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Proceedings Article | 28 May 2004 Paper

Immersion fluid refractive indices using prism minimum deviation techniques

Gerald Cooney, Simon Kaplan, Ron Synowicki, Greg Pribil, John Burnett, Roger French, Steven Green, Craig Herzinger, Min Yang, Michael Lemon

Proceedings Volume 5377, (2004) https://doi.org/10.1117/12.537727

KEYWORDS: Prisms, Refractive index, Liquids, Vacuum ultraviolet, Water, Thermal optics, Refraction, Immersion lithography, Nitrogen, Environmental sensing

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SPIE Journal Paper | 1 January 2004

Transparent fluids for 157-nm immersion lithography

Roderick Kunz, Michael Switkes, Roger Sinta, Jane Curtin, Roger French, Robert Wheland, Chien-Ping Kao, Michael Mawn, Lois Lin, Paula Wetmore, Val Krukonis, Kara Williams

JM3, Vol. 3, Issue 01, (January 2004) https://doi.org/10.1117/12.10.1117/1.1637366

KEYWORDS: Absorption, Immersion lithography, Liquids, Absorbance, Vacuum ultraviolet, Microfluidics, Water, Carbon monoxide, Oxygen, Chemical analysis

Proceedings Article | 12 June 2003 Paper

Single-layer fluoropolymer resists for 157-nm lithography

Kenneth Leffew, William Farnham, Frank Schadt, Robert Wheland, Viacheslav Petrov, Jerald Feldman, Fredrick Zumsteg, Michael Crawford, Roger French, Hoang Tran, Weiming Qiu, Andrew Feiring

Proceedings Volume 5039, (2003) https://doi.org/10.1117/12.485206

KEYWORDS: Absorbance, Polymers, Etching, Silicon, Resistance, Absorption, Fluorine, Lithography, Infrared radiation, Photoresist materials

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Proceedings Article | 30 July 2002 Paper

Behavior of candidate organic pellicle materials under 157-nm laser irradiation

Robert Wheland, Joe Gordan, Xun Zhang, Andrew Grenville, Roger French, Vladimir Liberman, Mordechai Rothschild, Jan Sedlacek

Proceedings Volume 4691, (2002) https://doi.org/10.1117/12.474604

KEYWORDS: Pellicles, Oxygen, Lamps, Polymers, Reticles, Semiconducting wafers, Absorption, Laser irradiation, Absorbance, Polymer thin films

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Proceedings Article | 30 July 2002 Paper

157-nm pellicles: polymer design for transparency and lifetime

M. Lemon, Vladimir Liberman, Roderick Kunz, Roger French, Weiming Qiu, Robert Wheland, Joe Gordon, Gregory Blackman, Mordechai Rothschild, Xun Zhang, A. Grenville

Proceedings Volume 4691, (2002) https://doi.org/10.1117/12.474605

KEYWORDS: Polymers, Pellicles, Absorbance, Transparency, Absorption, Quantum efficiency, Optical lithography, Lithography, Molecular lasers, Vacuum ultraviolet

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The introduction of 157 nm as the next optical lithography wavelength has created a need for new soft (polymeric) or hard (quartz) pellicle materials. Pellicles should be > 98% transparent to incident 157 nm light and, ideally, sufficiently resistant to photochemical damage to remain useful for an exposure lifetime of 7.5 kJ/cm2. The transparency specification has been met. We have developed families of experimental Teflon™AF (TAFx) polymers with > 98% transparency which can be spin coated and lifted as micron-scale, unsupported membranes. Still higher transparencies should be possible once optimization of intrinsic (composition, end groups, impurities, molecular weight) and extrinsic (oxygen, absorbed hydrocarbons, contaminants) factors are completed. The measured transparencies of actual pellicle films, however, are affected by many factors other than absorption. Film thickness must be precisely controlled so as to allow operation at the fringe maxima for the lithographic wavelength. Roughness and thickness uniformity are also critical. An important part of our program has thus been learning how to spin membranes from the solvents that dissolve our pellicle candidates. Meeting the durability specification at 157 nm remains a major concern. The 157 nm radiation durability lifetime of a polymer is determined by two fundamental properties: the fraction of 157 nm radiation absorbed and the fraction (quantum efficiency) of this absorbed radiation that results in photochemical darkening. Originally it was assumed that lifetime increases uniformly with increasing transparency. We now have cases where materials with very different absorbances (TAFx4P and 46P) have similar lifetimes and materials with similar absorptions (TAFx46P and 2P) have very different lifetimes. These findings demonstrate the importance of the relative quantum efficiencies as the 157 nm light energy distributes itself along degradative versus non-degradative pathways. In an effort to identify chemical and structural features that control lifetime, we have been studying model molecular materials, some quite similar to the monomer units used to make our pellicle candidates. Several of these models have shown transparencies much higher and lifetimes far longer than our best pellicle candidates to date.

Proceedings Article | 14 September 2001 Paper

Materials design and development of fluoropolymers for use as pellicles in 157-nm photolithography

Kenneth Sharp, Weiming Qiu, Roger French, David Jones, Xun Zhang, Robert Wheland, M. Lemon, Joseph Gordon, Fredrick Zumsteg

Proceedings Volume 4346, (2001) https://doi.org/10.1117/12.435710

KEYWORDS: Pellicles, Absorption, Polymers, Absorbance, Vacuum ultraviolet, Adhesives, Optical lithography, Atrial fibrillation, Spectroscopy, Transparency

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Proceedings Article | 24 August 2001 Paper

157-nm imaging using thick single-layer resists

Roger French, Andrew Feiring, Michael Crawford, Robert Smalley, Frank Schadt, Fredrick Zumsteg, Jerald Feldman, Viacheslav Petrov

Proceedings Volume 4345, (2001) https://doi.org/10.1117/12.436874

KEYWORDS: Absorption, Absorbance, Etching, Polymers, Lithography, Transparency, Vacuum ultraviolet, Photoresist materials, Scanning electron microscopy, Resistance

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Proceedings Article | 5 July 2000 Paper

Fluoropolymers for 157-nm lithography: optical properties from VUV absorbance and ellipsometry measurements

Andrew Feiring, Jerald Feldman, Robert Wheland, Roger French, James Hilfiker, David Jones, Ron Synowicki, Fredrick Zumsteg

Proceedings Volume 4000, (2000) https://doi.org/10.1117/12.388988

KEYWORDS: Absorbance, Pellicles, Vacuum ultraviolet, Polymers, Ellipsometry, Thin films, Spectroscopy, Reflectivity, Optical properties, Absorption

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With the introduction of 157 nm as the next optical lithography wavelength, the need for new pellicle and photoresist materials optimized for this wavelength has produced much activity in optical characterization of thin film materials. Here we focus on ultra transparent fluoropolymers for 157 nm pellicle applications where absorbances below 0.01/micrometers are necessary to achieve transmissions above 98 percent. Transmission-based absorbance/micrometers measurements performed using VUV spectroscopy are characterized by rapid turn-around time, and are essential during the materials design and screening phase of a new materials development program. Once suitable candidate materials families have been identified for development into 157 nm pellicles, VUV ellipsometry becomes essential to model the film structure, characterize the complex index of refraction, and to tune the pellicle's etalon design. Comparison of VUV absorbance measurements of fluoropolymer thin films on CaF₂ substrates with VUV ellipsometry measurements of the same polymers on silicon substrates demonstrates some of the artifacts in, and helps define the accuracy of transmission based absorbance measurements. Fresnel interference fringes can produce transmission oscillations that can lead to underestimation, or even negative values, of the film absorbance. Film thickness nonuniformity can serve to reduce the Fresnel interference fringes, leading to reduce variation in the apparent 157 nm absorbance for micrometers thick films. VUV ellipsometry coupled with Fresnel analysis of the thin film/substrate system formally takes into consideration all of these optical artifacts, while at the same time determining the complex index of refraction of the materials. Using VUV ellipsometry and Fresnel analysis, the absorbance values do not show the large apparent oscillations, the film thickness is directly determined in the measurement, and film microstructure is also modeled. We have identified ultra transparent fluoropolymers which have 157 nm absorbances below 0.01/micrometers . These materials have the appropriate optical properties for use as 157 nm pellicles with greater than 98 percent transmission. This is an important for the development of 157 nm lithography, since the lack of a 157nm pellicle has been identified as a critical path issue.

Proceedings Article | 23 June 2000 Paper

New materials for 157-nm photoresists: characterization and properties

Robert Smalley, Susan Holl, Roger French, Fredrick Zumsteg, Andrew Feiring, Mookkan Periyasamy, Ling Liao, Roderick Kunz, Veena Rao, Frank Schadt, Michael Crawford, Jerald Feldman

Proceedings Volume 3999, (2000) https://doi.org/10.1117/12.388319

KEYWORDS: Etching, Transparency, Resistance, Polymers, Plasma etching, Photoresist materials, Plasma, Photoresist developing, Lithography, Absorption

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Proceedings Article | 30 June 1999 Paper

Optical superlattices as phase-shift masks for microlithography

Greg Hughes, Charlie Torardi, Roger French, Peter Carcia, Laurent Dieu, L. Wilson, C. Miao, Gillian Reynolds, David Jones, M. Lemon, M. Reilly

Proceedings Volume 3790, (1999) https://doi.org/10.1117/12.351257

KEYWORDS: Photomasks, Etching, Multilayers, Optical lithography, Quartz, Chromium, Transmittance, Superlattices, Optical properties, Reactive ion etching

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Proceedings Article | 18 December 1998 Paper

TiSi-nitride attenuating phase-shift photomask for 193-nm lithography

M. Lemon, David Jones, Peter Carcia, C. Miao, Gillian Reynolds, Roger French, Charlie Torardi, Greg Hughes, M. Reilly, L. Wilson

Proceedings Volume 3546, (1998) https://doi.org/10.1117/12.332857

KEYWORDS: Etching, Photomasks, Lithography, Quartz, Transmittance, Chemistry, Dry etching, Reactive ion etching, Chromium, Wet etching

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Proceedings Article | 27 December 1996 Paper

Materials screening for attenuating embedded phase-shift photoblanks for DUV and 193-nm photolithography

Bruce Smith, Jeff Meth, Kenneth Sharp, Roger French, Peter Carcia

Proceedings Volume 2884, (1996) https://doi.org/10.1117/12.262809

KEYWORDS: Deep ultraviolet, Multilayers, Optical properties, Sputter deposition, Photomasks, Composites, Transmittance, Etching, Inspection, Phase shifts

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Proceedings Article | 22 May 1995 Paper

Metrology of etched quartz and chrome embedded phase shift gratings using scatterometry

Roger French, Blaine Johs, Franklin Kalk, S. Sohail Naqvi, Susan Wilson, Herschel Marchman, John McNeil

Proceedings Volume 2439, (1995) https://doi.org/10.1117/12.209233

KEYWORDS: Photomasks, Quartz, Etching, Diffraction gratings, Phase shifts, Oxides, Scatterometry, Atomic force microscopy, Diffraction, Scatter measurement

Proceedings Article | 7 December 1994 Paper

Chromium-based attenuated embedded shifter preproduction

Roger French, Greg Hughes, H. Ufuk Alpay, Franklin Kalk

Proceedings Volume 2322, (1994) https://doi.org/10.1117/12.195825

KEYWORDS: Phase shifts, Photomasks, Inspection, Etching, Scanning electron microscopy, Photomask technology, Phase shifting, Dry etching, Absorbance, Optical inspection

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