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Search Publications by: Wen-Li Wu (Assoc)

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Displaying 1 - 25 of 193

Additive-Containing Rinses for LER and Defectivity Control During High-Resolution Resist Patterning

October 12, 2021
D L. Goldfarb, S D. Burns, M Angelopolous, S Skordas, R L. Burns, M C. Lawson, C J. Brodsky, V Vishnu, E Jablonski, Vivek Prabhu, Ronald L. Jones, B D. Vogt, Christopher Soles, Eric K. Lin, Wen-Li Wu
The addition of a surface conditioning agent to the de-ionized water rinse used to quench the photoresist development process is an attractive methodology that can afford a controlled decrease in resist line edge roughness (LER) or a reduction in

Chemically Amplified Photoresists Fundamental Properties and Limits of Applicability to Sub-100 nm Lithography

October 12, 2021
D M. Goldfarb, Eric K. Lin, Christopher Soles, B C. Trinque, S D. Burns, Ronald L. Jones, Joseph~undefined~undefined~undefined~undefined~undefined Lenhart, M Angelopoulos, C G. Wilson, Sushil K. Satija, Wen-Li Wu
State-of-the-art lithographic technologies combine chemically amplified photoresists and sophisticated radiation sources to delineate patterned areas with high spatial resolution, enabling the fabrication of continually decreasing feature sizes in the

Determination of the Complex Modulus of a Supported Ultra-Thin Polymer Film

October 12, 2021
Christopher C. White, Wen-Li Wu
A novel technique to quantitatively measure the complex modulus of ultra-thin polymer films (sub micron) is described. This technique employs a new mechanical impedance expression developed from a two-layer viscoelastic media model. This result is combined

Low Dielectric Constant Nanocomposite Thin Films Based on Silica Nanoparticle and Organic Thermosets

October 12, 2021
Q Lin, Stephen Cohen, Lynne Gignac, Brian Herbst, David Klaus, Eva Simonyi, Jeffrey Hedrick, John Warlaumont, Hae-Jeong Lee, Wen-Li Wu
Low dielectric constant (low-k) nanocomposite thin films have been prepared by spin coating and thermal cure of solution mixtures of two organic low-k thermoset pre-polymers and a silica nanoparticle with an average diameter of about 8nm. The electrical

Understanding Deviations in Lithographic Patterns Near Interfaces: Characterization of Antireflective Coatings (ARC) and the ARC/Resist Interface

October 12, 2021
Joseph~undefined~undefined~undefined~undefined~undefined Lenhart, Daniel A. Fischer, S Sambasivan, Eric K. Lin, Wen-Li Wu, Douglas Guerrero, Yijun Wang, R Puligadda
Interactions between a bottom anti-reflective coating (BARC) and a photo-resist can critically impact lithographic patterns. For example, a lithographic pattern can shrink or spread near a BARC interface, a process called undercutting or footing

Electron Reflectometry for Measuring Nanostructures on Opaque Substrate

July 8, 2019
Lawrence H. Friedman, Wen-Li Wu
Here, we present a method for measuring dimensions of nanostructures using specular reflection of electrons from an opaque surface. Development of this method has been motivated by measurement needs of the semiconductor industry, but it can also be more

X-ray Metrology for the Semiconductor Industry Tutorial

February 1, 2019
Daniel F. Sunday, Wen-Li Wu, Scott Barton, Regis J. Kline
The semiconductor industry is in need of new, in-line dimensional metrology methods with higher spatial resolution for characterizing their next generation nanodevices. The purpose of this short course is to train the semiconductor industry on the NIST

Characterization of Buried Structure in Directed Self Assembly Block Copolymers

July 30, 2014
Daniel F. Sunday, Matthew R. Hammond, Chengqing C. Wang, Wen-Li Wu, Dean M. DeLongchamp, Regis J. Kline, Melia Tjio, Joy Cheng, Jed W. Pitera
The directed self assembly (DSA) of block copolymers (BCP) can multiply or subdivide the pitch of a lithographically defined chemical or topological pattern and is a resolution enhancement candidate to augment conventional lithography for patterning sub-20

3D X-ray Metrology for Block Copolymer Lithography Line-Space Patterns

July 15, 2013
Daniel F. Sunday, Matthew R. Hammond, Chengqing C. Wang, Wen-Li Wu, Regis J. Kline, Gila E. Stein
We report on the development of a new measurement method, resonant critical-dimension small-angle x-ray scattering (CD-SAXS), for the characterization of the buried structure of block copolymers (BCP) used in directed self assembly (DSA). We use resonant

Critical Dimension small angel X-ray scattering measurements of FinFET and 3D memory structures

April 8, 2013
Regis J. Kline, Daniel F. Sunday, Chengqing C. Wang, Wen-Li Wu, Charlie Settens, Bunday Benjamin, Brad Thiel, Matyi Richard
Critical dimension small angle X-ray scattering (CD-SAXS) has been identified as a potential solution for measurement of nanoscale lithographic features by interrogating structures with sub-nanometer wavelength radiation in transmission geometry. The most

Intercomparison between optical and x-ray scatterometry measurements of FinFET structures

April 8, 2013
Paul Lemaillet, Thomas Germer, Regis J. Kline, Daniel Sunday, Chengqing C. Wang, Wen-Li Wu
In this paper, we present a comparison of profile measurements of vertical field effect transistor (FinFET) fin arrays by optical critical dimension (OCD) metrology and critical dimension small angle X-ray scattering (CD-SAXS) metrology. Spectroscopic

Neutron reflectivity characterization of the photoacid reaction-diffusion latent and developed images of molecular resists for extreme-ultraviolet lithography

May 11, 2012
Vivek M. Prabhu, Shuhui Kang, Wen-Li Wu, Sushil K. Satija, Christopher K. Ober, Jing Sha, Peter V. Bonnesen
Lithographic feature size requirements have approached a few radius of gyration of chemically-amplified photoresist polymers used in thin film patterning. Further, the feature dimensions are commensurate with the photoacid diffusion length that defines the

Characterization of the non-uniform reaction in chemically-amplified calix[4]resorcinarene molecular resist thin films

July 19, 2011
Vivek M. Prabhu, Shuhui Kang, Regis J. Kline, Dean M. DeLongchamp, Daniel A. Fischer, Wen-Li Wu, Sushil K. Satija, Jing Sha, Christopher K. Ober, Peter V. Bonnesen
The ccc stereoisomer-purified tert-butoxycarbonyloxy (t-Boc) protected calix[4]resorcinarene molecular resists blended with photoacid generator exhibit a non-uniform photoacid catalyzed reaction in thin films. The surface displays a reduced reaction extent

Lateral Uniformity in Chemical Composition along a Buried Reaction Front in Polymers

November 15, 2010
Kristopher Lavery, Vivek Prabhu, Sushil K. Satija, Wen-Li Wu
Off-specular neutron reflectometry was applied to characterize the form and amplitude of lateral compositional variations at a buried reaction-diffusion front. In this work, off-specular neutron measurements were first calibrated using off-specular X-ray

Photoresist latent and developer images as probed by neutron reflectivity methods

September 16, 2010
Vivek M. Prabhu, Shuhui Kang, David L. VanderHart, Eric K. Lin, Wen-Li Wu
Photoresist materials enable the fabrication of advanced integrated circuits with ever decreasing feature sizes. As next-generation light sources are developed, using extreme ultraviolet light of wavelength 13.5 nm, these highly-tuned formulations must

Elastic constants and dimensions of imprinted polymeric nanolines determined from Brillouin light scattering

January 18, 2010
Ward L. Johnson, Sudook A. Kim, Roy H. Geiss, Colm Flannery, Paul R. Heyliger, Christopher L. Soles, Wen-Li Wu, Chengqing C. Wang, Christopher M. Stafford, B D. Vogt
Elastic constants and cross-sectional dimensions of imprinted nanolines of poly(methyl methacrylate) (PMMA) on silicon are determined nondestructively from finite-element inversion analysis of dispersion curves of hypersonic acoustic modes of these

Small Angle X-Ray Scattering Measurements of Spatial Dependent Linewidth in Dense Nanoline Gratings

March 16, 2009
Chengqing C. Wang, Wei-En Fu, Bin Li, Huai Huang, Christopher Soles, Eric K. Lin, Wen-Li Wu, Paul S. Ho, Michael W. Cresswell
Small angle X-ray scattering (SAXS) was used to characterize the line cross section of nanoline gratings fabricated using electron beam lithography (EBL) patterning followed by anisotropic wet etching into silicon single crystal. SAXS results at normal