Background Image

News & Events


Clarkson University's Babu Receives 30th Patent

Clarkson University Distinguished University Professor and Center for Advanced Materials Processing (CAMP) Director S.V. Babu received his 30th patent this past fall on U.S. Patent 8,822,340, “Abrasive compositions for chemical mechanical polishing and methods for using same.”

S.V. BabuHis co-inventors are Pradeepa Dandu (now at Intel) and Vamsi K. Devarapalli (now at IBM), both former Ph.D. students of Babu, and Guillaume Criniere and Claire Pitosis (both of Rhodia, now part of Solvay).
Chemical-mechanical planarization (CMP) generally involves the planarization at the nanolevel of uneven topography on a substrate’s surface, typically a semiconductor-related substrate. The planarized surface allows for a much higher precision in photolithography, allowing a large number of interconnecting metal layers to be added sequentially on the substrate surface, analogous to a multi-story structure.

The CMP process includes slurry and a polishing pad. The polishing slurry typically contains abrasive particles dispersed in a liquid carrier. It is applied to the substrate’s surface using the polishing pad, mounted on a platen in a polishing tool. A rotating head holds the substrate against the polishing pad to achieve the planarized substrate surface. This type of CMP process combines a "mechanical" effect of smoothing with abrasive particles and a "chemical" effect of reacting with acidic or basic fluid solution.

In traditional CMP processes, a high silicon dioxide and a low silicon nitride removal rate are desired to minimize loss of the nitride film. In contrast, there are certain new applications where the reverse, i.e., a high nitride and a low oxide removal rate, the so-called reverse selectivity, is desirable. Such reverse selectivity, however, has been very difficult to achieve.

This new invention, developed jointly with Rhodia, provides a stabilized composition containing ceria abrasives for use in the CMP process to achieve the desired high reverse selectivity.

Babu is an expert in the field of chemical-mechanical planarization. He has supervised 41 Ph.D. and 38 master of science students and is a co-author of more than 240 professional publications, including more than 180 peer-reviewed publications.

He has co-organized many symposiums and served as a keynote speaker numerous times. Among other honors, he is a recipient of the 2004 IBM Faculty Award and was honored in 2010 with a Visiting Professorship for Senior International Scientists by the Chinese Academy of Sciences in Shanghai. In addition, the World Education Congress, held in Mumbai, India, honored him in 2012 with an Education Leadership Award for his outstanding leadership and contributions to the field of education.

Clarkson University launches leaders into the global economy. One in five alumni already leads as a CEO, VP or equivalent senior executive of a company. Located just outside the Adirondack Park in Potsdam, N.Y., Clarkson is a nationally recognized research university for undergraduates with select graduate programs in signature areas of academic excellence directed toward the world’s pressing issues. Through 50 rigorous programs of study in engineering, business, arts, sciences and the health professions, the entire learning-living community spans boundaries across disciplines, nations and cultures to build powers of observation, challenge the status quo, and connect discovery and engineering innovation with enterprise.

[A photograph for media use is available at .]

[News directors and editors: For more information, contact Annie Harrison, Director of Media Relations, at 315-268-6764 or]

Calendar View the full calendar >>

Full Calendar RSS Feed