Surface Adsorption Behavior in a Model CMP Slurry

Due to their high surface area, abrasive particles in CMP slurry can have a significant impact on the effective concentration of key chemical components, which in turn, can have a profound influence on the slurry performance. Working with Dr. William America of IBM, Professor Yuzhuo Li and his graduate students Fadwa Odeh and Sameer Dhane have conducted research to observe the adsorption of a key ingredient in the slurry, benzotriazole (BTA) onto the surface of representative abrasive particles such as silica. It was observed that the extent of surface adsorption is heavily controlled by the type of silica and the presence of other chemicals such as glycine and copper ions. The complex formed between BTA and copper ions results in a greater driving force for the surface adsorption. Furthermore, the copper ions introduced during the CMP process have an even greater impact on the adsorption behavior of BTA and other key chemical ingredients. This research is particularly useful in providing insight into the chemical mechanical polishing mechanism and the further optimization of a CMP slurry.

Forces between Nanoparticles, Fundamentals of CMP, Nanobiosensors, Self-Assembly of Nanoporous Colloids, Film Coating, Nanocomposites, and Biophysics (Human Skin, Ageing of Human Cells, Bacterial Bioremediation)

CAMP Professor Igor Sokolov, from the Department of Physics at Clarkson University, uses Scanning Probe Microscopy (SPM) for a variety of research topics. He has used SPM to study the fundamentals of copper CMP. The SPM tip was used to mimic a single abrasive silica particle, typical of those used in CMP slurry, to study the removal rate of copper oxides (collaboration with CAMP Professor Babu). He is using the SPM in a project involving the measurement of particle-wafer and particle-pad interactions using an Atomic Force Microscope (collaboration with CAMP Professor Subramanian).

Professor Sokolov is working with CAMP Professor Ian Suni, in studying a new architecture of biosensors. He also studies glucose biosensor molecules in cooperation with Professor Linda Luck, of Clarkson's Biology Department

Professor Sokolov's research includes self-assembly of nanoporous colloids with different shapes and various functions. This includes making "smart dust" particles with encoded color "bar codes" (patent pending), which can be used in biomedical labeling, security and product tagging. (See Figure 2.)

In addition Professor Sokolov is investigating the force interaction in complex biological systems, including epithelial human cells and various bacteria. In collaboration with Professor Craig Woodworth (of Clarkson's Department of Biology), he studies the mechanical properties of ageing human cells. He is also collaborating with CAMP Professor Anja Mueller and Professor Stefan Grimberg (of Clarkson's Civil and Environmental Engineering Department) to study molecular mechanisms of bacterial interaction with various oils during the process of bioremediation.

Figure 2: An image of smart dust particles that are really nanoporous glass.


Figure 2 and 3

CAMP Technical Writer and Editor Dr. Dana M. Barry accepts a ChemLuminary Award for Public Relations on behalf of the Northern NY section of the American Chemical Society (ACS), at the ACS National Convention in Philadelphia, PA on August 24. This national award was for Dr. Barry's Chemical Sensation Project. From left: Dr. William Oliver (Chair of the Committee on Public Relations and Communications), Dr. Dana Barry (officer of the Northern NY section of the ACS), and Dr. James Burke (Chair of the Board of Directors of the ACS).

Northern NY Section of the American Chemical Society Receives National Awards for Programs Run by Clarkson's Dr. Dana Barry

The Northern New York section of the American Chemical Society (ACS) received national awards for programs run by Dr. Dana Barry, technical writer and editor of Clarkson University's Center for Advanced Materials Processing. The section received a ChemLuminary Award in Public Relations for Dr. Barry's Chemical Sensation Project with Japan, as well as a ChemPower Award (Certificate of Excellence) for her World First MarsLink Space Mission Program. The awards were presented at the ACS National Convention held during the month of August in Philadelphia, PA.

The Chemical Sensation Project is an international effort to promote and improve perceptions of chemistry and chemical professionals. Dr. Barry's main collaborator for this project is Professor Hideyuki Kanematsu of Suzuka National College of Technology in Japan. Dr. Barry's Mars Mission Program provides students with a unique opportunity to experience first hand the excitement of chemistry through an educational program linked to the NASA Mars Missions.

Her international team has participants in the United States and Malaysia. She has program support from Space Explorers Inc., and her main collaborator is Dr. Roger Haw, Co-Founder of Ansted University.

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Research on Obscurants

Senior University Professor Richard Partch is involved with research on obscurants. He and Professor Goia have already prepared several samples of potential obscurants (in their CAMP laboratories) by a combination of chemical and physical methods. Separate from experimentation at CAMP, Professor Partch is coordinator / leader for a team of scientists at U.S. Army Edgewood laboratories, Sigma Technologies International Inc. and CAMP. The focus of the team is to adapt and improve Sigma's capabilities to produce aluminum flakes having optimized morphology for IR obscuration. This teamwork is funded by a grant from the U.S. Army which supports the activity of Sigma.

Electrochemical Deposition of Metals for Semiconductor/ Nanotechnology Applications

Electrochemical methods provide inexpensive and powerful tools to deposit nanostructures and to tailor the nanostructure of surfaces. CAMP Professor Ian Suni is using electrochemical deposition and dissolution of metals to form controlled nanostructures for applications to semiconductor processing, catalysis, and biosensor development. For example, he recently developed an electrochemical method for depositing a Cu seed layer atop the Ta barrier layer during interconnect formation on Si devices. Another CAMP project involves the development of electrochemical methods for copper planarization during Si device fabrication. Professor Suni is also involved in fundamental research supported by the National Science Foundation to develop new electrochemical biosensors.

. Quantum Physics for Nanotechnology and Information Processing

CAMP Professor Vladimir Privman, of Clarkson University's Departments of Chemistry, Electrical and Computer Engineering, and Physics, is the Director of the ARO and NSF-funded Center for Quantum Device Technology. He is exploring implications of quantum physics for future nanotechnology and information processing. He has also contributed to theories of uniform fine particles. Professor Privman's main contributions have been in developing and evaluating approaches to utilize semiconductor heterostructures and quantum wells, based on the silicon-chip device technology, for quantum information processing (quantum computing) and spintronics. He has also worked in modeling electron transport of relevance to single-quantum measurement and control.


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