March Newsletter: Page 1
Twenty Years of CMP Research and Development at Clarkson University’s CAMP
Distinguished University Professor and CAMP Director S.V. Babu
Clarkson’s Center for Advanced Materials Processing (CAMP) has carried out research involving chemical-mechanical planarization (CMP) for over twenty years now under the guidance and leadership of Distinguished University Professor S.V. Babu, the current CAMP Director since 1999.
CMP is a crucial enabling technology for the fabrication of complex logic and memory devices and other integrated circuit structures. It is used to planarize unwanted topographical features by selective material removal at each metallization level during the fabrication of these devices. This is necessary because of the limitations caused by the shallow depth of focus of the optical lithography tools used to create the ever shrinking features of present and future generation semiconductor devices. The CMP process requires the use of slurry and a polymeric polishing pad. The polishing slurry typically contains abrasive particles dispersed in a liquid carrier and is applied to the substrate’s surface using the polishing pad, mounted on a rotating platen in a polishing tool. A rotating head holds the wafer substrate face down against the rotating polishing pad while the uneven topography is planarized.
CMP began at CAMP as a result of two white papers written in 1993. These papers were developed through the discussions of CAMP Professors S.V. Babu, Ahmed Busnaina, Raymond Mackay, Egon Matijevic, Richard Partch, and Don Rasmussen with two former IBM technical managers and researchers, Drs. Mike Fury and Frank Kaufman. The white papers addressed the multiple problems and challenges in understanding and improving the CMP processes being developed and used in the semiconductor industry. The technical directions proposed in these documents exploited the expertise and skills existing at CAMP in thin film processing, particle synthesis, particle coatings, colloidal chemistry, surfactants, process control instrumentation, and in the removal of particles from finished surfaces. The startup CMP activity, which involved the combined efforts of all these CAMP researchers, took place in Professor Babu’s laboratory at CAMP using a polishing tool donated to CAMP by Strasbaugh, Inc. and test wafers for experimental trials donated by IBM in Burlington. The initial experimental efforts at CAMP on CMP were ably and expertly led by Dr. David Campbell, a retired Senior IBM engineer and manager.
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Professor Maria Gracheva Receives Tenure and Is Promoted to Associate Professor at Clarkson University
Professor Maria Gracheva has been granted tenure and promoted from Assistant Professor to Associate Professor in Clarkson University’s Department of Physics. She joined Clarkson in 2008. Before coming to Clarkson, Gracheva worked as a postdoctoral associate at Beckman Institute for Advanced Science and Technology at the University of Illinois (Urbana-Champaign), in the Department of Mathematics at the University of Minnesota (Minneapolis) and in the Physics Department at Lehigh University.
Professor Gracheva received a Master of Science degree and a Doctoral degree in solid state physics from Moscow State Engineering Physics Institute (MEPhI) in Russia. Her research expertise is in solid state physics, engineering physics, biophysics and the use of computer simulations in physics. She received National Science Foundation (NSF) support in the form of the CAREER Award and an EAGER award (Early-Concept Grants for Exploratory Research) for her research on electrically tunable membranes for characterization, separation and filtering of ions and biomolecules such as DNA and proteins. She has secured over $700,000 in funding from the NSF and other agencies. In addition, Gracheva is listed in Marquis Who’s Who in Science and Engineering, 10th Anniversary Edition, 2008-2009.
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Professor Ajit Achuthan Receives Tenure and Is Promoted to Associate Professor at Clarkson University
Professor Ajit Achuthan has been granted tenure and promoted from Assistant Professor to Associate Professor in Clarkson University’s Department of Mechanical & Aeronautical Engineering. He joined Clarkson in 2009. Before coming to Clarkson, Achuthan was an instructor and post-doctoral fellow with the School of Aeronautics & Astronautics at Purdue University and a mechanical engineer at the General Electric Global Research Center in Niskayuna, N.Y.
He received a Bachelor of Technology degree in civil engineering from Calicut University in India, a Master of Science degree in aerospace engineering from the Indian Institute of Technology, a Master of Engineering in civil engineering from the National University of Singapore, and a Ph.D. in aeronautics and astronautics from Purdue University. His research interest lies in the general area of solid mechanics. Specific research problems that he currently focuses on include material microstructure and residual stress evolution under severe environmental conditions as in additive manufacturing; crystal plasticity finite element modeling; nanoscale material instability; and acoustic metamaterials.
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