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Search Publications by: Alamgir Karim (Assoc)

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Displaying 26 - 50 of 100

Pattern-directed to isotropic dewetting transition in polymer films on micropatterned surfaces with differential surface energy contrast

January 27, 2007
Author(s)
D Julthongpiput, Wenhua Zhang, Jack F. Douglas, Alamgir Karim, Michael J. Fasolka
Surface chemical patterns can both cause and direct dewetting in overlying thin films. However, a key factor in this behavior, the magnitude of surface energy differences between pattern domains ( ?g ), is largely unevaluated. To probe the effect of this

Wetting-Dewetting Transition Line in Thin Polystyrene Films

September 9, 2005
Author(s)
H Raghavan, K M. Ashley, A Seghal, Jack F. Douglas, Alamgir Karim
We review recent advances in the application of combinatorial methods to polymer thin film characterization. Combinatorial methods allow the rapid exploration of multidimensional parameter spaces that naturally arise in the description of polymer film

Combinatorial Peel Tests for the Characterization of Adhesion Behavior of Polymeric Films

February 1, 2005
Author(s)
R Song, Martin Chiang, A J. Crosby, Alamgir Karim, Eric J. Amis, Naomi Eidelman
The self-adhesion behavior of an optically smooth poly(methyl methacrylate) (PMMA) thin film (ca.. 100 nm) on different evaporated metal substrates has been investigated using a combinatorial method approach. In this investigation through high-throughput

Discrete Combinatorial Investigation of Polymer Mixture Phase Boundaries

January 1, 2005
Author(s)
J Cabral, Alamgir Karim
We report a combinatorial approach for mapping bulk polymer mixture phase behavior. The technique consists of a parallel cloud point detection scheme using discrete composition libraries, which are scanned across a temperature range and optically imaged

A New Design for High-Throughput Peel Tests: Statistical Analysis and Example

December 1, 2004
Author(s)
A Chiche, Weiping Zhang, Christopher Stafford, Alamgir Karim
The peel test is one of the most common techniques to investigate the properties of pressure sensitive adhesives (PSAs). As the demand increases for combinatorial tools to rapidly test material performance, designinig a high-throughput peel test is a

A Buckling-Based Metrology for Measuring the Elastic Moduli of Polymeric Thin Films

August 1, 2004
Author(s)
Christopher Stafford, Eva Simonyi, C Harrison, Kathryn Beers, Alamgir Karim, Eric J. Amis, Mark R. VanLandingham, H C. Kim, W Volksen, R D. Miller
As technology continues towards smaller, thinner and lighter devices, more stringent demands are placed on thin polymer films as diffusion barriers, dielectric coatings, electronic packaging and so on. Therefore, there is a growing need for testing

An Open Source Informatics System for Combinatorial Materials Research

March 1, 2004
Author(s)
Weiping Zhang, Michael J. Fasolka, Alamgir Karim, Eric J. Amis
Laboratory Research Informatics Systems (LRIS) hold great promise in streamlining research generally, and are particularly necessary for new data-intensive research strategies such as combinatorial and high-throughput approaches. In this talk, we describe

Energy Analysis of Multi-Lens Adhesion Measurements

March 1, 2004
Author(s)
Aaron M. Forster, Christopher Stafford, Alamgir Karim
The NIST Combinatorial Methods Center (NCMC) has adapted the Johnson Kendall, and Roberts (JKR) adhesive contact test for the development of a high-throughput adhesion measurement platform. This technique utilizes an array of hemispherical lenses to

Finite-Size Effects on Surface Segregation in Polymer Blend Films Above and Below the Critical Point of Phase Separation

March 1, 2004
Author(s)
H Grull, Li Piin Sung, Alamgir Karim, Jack F. Douglas, Sushil K. Satija, Makoto Hayashi, H Jinnai, TT Hashimoto, Charles C. Han
We investigate the influence of temperature and confinement on surface segregation in thin films of deuterated polybutadiene and polyisoprene near the critical point for phase separation. Neutron reflectivity measurements show that polyisoprene enriches at

Combinatorial Techniques to Measure Curing of Epoxy Films

February 1, 2004
Author(s)
Aaron M. Forster, D Ragahavan, Naomi Eidelman, Alamgir Karim
Combinatorial methods were implemented in the investigation of time and temperature effects on epoxy curing by using three complementary techniques: axisymmetric adhesion testing, FT-IR reflectance mapping, and confocal fluorescence mapping to characterize

Phase Behavior of PS - PVME Nanocomposites

January 1, 2004
Author(s)
K Yurekli, Alamgir Karim, Eric J. Amis, R Krishnamoorti
The influence of nanometer thick, highly anisotropic organically modified layered silicate (montmorillonite) on the phase behavior of deuterated polystyrene (dPS) and polyvinylmethylether (PVME) is investigated using a combination of small angle neutron

Combinatorial Chemistry

October 13, 2003
Author(s)
J D. Hewes, Debra L. Kaiser, Alamgir Karim, Eric J. Amis
In 1995, the rapid fabrication of tens, hundreds, and, eventually, tens of thousands of samples in two-dimensional arrays of discrete microscaled samples (pixels) using lithography methods developed for the electronics industry was reported. Importantly

Combinatorial Characterization of Cell Interactions with Polymer Surfaces

September 1, 2003
Author(s)
J C. Meredith, J L. Sormana, B G. Keselowsky, A J. Garcia, Alessandro Tona, Alamgir Karim, Eric J. Amis
The combinatorial library and high-throughput techniques presented here allow rapid, efficient, and accurate exploration of the effects of microstructure and surface features on cell adhesion and proliferation. The new technique serves as a natural

High-Throughput Measurements of Polymer Adhesion and Mechanical Properties

September 1, 2003
Author(s)
Christopher Stafford, Aaron M. Forster, C Harrison, Cher H. Davis, Eric J. Amis, Alamgir Karim
Polymer adhesion is important to numerous technologies including electronic packaging, coatings and paints, biomedical implants, and pressure-sensitive adhesives. The challenge is to understand the fundamental driving forces for the development of adhesive

Modification of Thin Film Phase Separation by a Surfactant

March 25, 2003
Author(s)
Li Piin Sung, Alamgir Karim, Jack F. Douglas, Charles C. Han
Phase separation in thin films leads to the formation of surface patterns (holes, bumps, and bicontinuous surface features) which depend on the film composition. These features are interpreted to arise from surface tension variations within the film that

Chemically Amplified Resist Fundamentals Studies by Combinatorial approaches

March 1, 2003
Author(s)
M Wang, Vivek Prabhu, Eric K. Lin, Michael J. Fasolka, Alamgir Karim
Sub-100 nm lithography requires more understanding of photoresist material properties and processing conditions to achieve necessary critical dimension control of patterned structures. As resist thickness and feature linewidth decrease, fundamental