CAMP Annual Report: Page 7
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The group is also investigating the planarization of dielectric (oxide, nitride, poly-Si and recently some polyimides) films with controlled and variable selectivity. The investigation of controlled selectivity in material removal during the polishing of oxide, nitride, and poly-Si films has led to several fundamental discoveries. Several ceria and silica based compositions that yield a high nitride and low oxide polish rate and simultaneously a controllable poly-Si removal rate have been identified. It was shown that the presence of protonated functional groups of the additive is critical to suppress nitride removal to a few angstroms/min., since they can bind through strong hydrogen bonding to the nitrogen with unpaired electrons on the nitride surface. Both the stress and doping of the nitride film also play a critical role.
Aqueous and abrasive-free solutions of PDADMAC and PEI as well as several other polymers have been shown to polish poly-Si film at high rates with no oxide or nitride removal. The results were published in several recent papers. Some of these compositions were used to improve the surface finish of extreme UV lithography mask substrates. Continuing the collaboration with Lee Cook’s group at Dow, additives to these abrasive-free solutions that yield non-prestonian behavior were identified. This work is continuing.
The Photo-Acoustic Research (PAR) and Nanomechanics/Nanomaterials (NN) Laboratories (PAR) directed and co-directed by Professor Cetin Cetinkaya have been conducting analytical, computational, and experimental studies in the areas of laser-based particle removal and contact/non-contact adhesion measurements. There is a critical need in various industries for accurate adhesion measurements and characterization of micro/nanoparticles on flat and rough substrates. The PAR Lab has developed a novel characterization method to quantify the adhesion properties of single microparticles in a non-contact/non-destructive manner under various conditions. Since the non-contact method does not require the dislodgement of the particle from its substrate, the contributions of external effects, such as humidity, electrical field, and temperature, can be studied on a single particle at the same contact point. The recent focus is on the investigation of graphene adhesion. The PAR lab is developing a technique to measure the work-of-adhesion of the graphene-SiO2 interface. The PAR and NN laboratories have received research funds from the National Science Foundation, Intel, SEMATECH, Xerox Corporation, Wyeth Pharmaceuticals, Pfizer Inc., the Consortium for the Advancement of Manufacturing in Pharmaceuticals (CAMP), Praxair/Electronics, the US Army, as well as the Center for Advanced Materials Processing (CAMP) at Clarkson.
Summer 2012 research activities carried out by Senior University Professor Richard Partch and his group concluded with considerable success in achieving goals for sources of external funding.
Six undergraduates from Clarkson, Syracuse University and SUNY Buffalo obtained data on 1) use of paper manufacturing waste sludge as a feed for conversion to oil in a batch reactor at high pressure and temperature; 2) preparation of gold nanoparticles functionalized with an organo platinum cancer chemotherapy derivative and death rates of normal versus cancer cells; and 3) isolation of Urushiol, the benzenoid catechol active irritant in poison ivy, and determining ability to bond the molecule to a receptor having potential as an antidote.
Graduate students Jim Touchette and David Gervasi completed their degrees studying filled rubber composites designed to reduce energy used by copy machines, and Justen Schaefer's thesis dealt with various aspects of freeze drying nanoparticles. Data by the former two make it possible to reduce toner fuser roller temperature by 50oC. Ph.D. students Lifeng Chen, Chenyu Lin and Meghan Molloy have made great progress on their respective topics: microcapsules for improved thermal printing; determining kinetic and functional group factors for charge transfer interaction between aromatic rings; and crystallization and surface reaction of benzotriazole derivatives.
Research technicians Eddie Howell, Chris Lanthier, Jon Sampson, Deborah Shipp, Dinusha Siriwardena and Tania Tannahill advanced understanding on 1) deinking of paper printed with toner containing polymer from renewable plant sources, 2) making new bio-based toner less moisture sensitive, and 3) preparing microcapsules capable of releasing core liquid on demand for sensing and neutralizing biological hazards.
New projects have been funded by Corning, Inc. on aspects of glass technology and by Polymer Group Int. on non-woven fabric treatment.
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