Sep 18 2007
A patent for a new way of making an industrial ceramic that is used widely in semiconductors, industrial abrasives, and as a diamond substitute has been issued to University of Massachusetts Amherst chemist Patricia Bianconi.
The new process for making silicon carbide (commercially known as Carborundum) yields super-smooth ceramic films and is cheaper and more energy efficient that other ways of producing the material. And because the resulting ceramic is polymer-based, it can be shaped into usable products more easily than silicon carbide made by traditional means.
Polymer precursors to silicon-based ceramics have been studied for several decades, but smooth films of silicon carbide suitable for electronic uses have not yet been produced from those precursors. So Bianconi and graduate students Michael Pitcher and Scott Joray decided to try making smooth ceramic films using new polymers called polysilynes. These polymers were synthesized with a specially designed structure consisting of a silicon backbone with carbon-based side chains. When heated under an inert gas such as argon, carbon atoms from the side chain react with the silicon backbone, decomposing into a solid, hard ceramic film.
Bianconi’s new method results in ceramic films that are the smoothest, most continuous and defect free ceramic films ever reported from polymer precursors. And the newly patented process is extremely efficient; whatever quantity of ingredients is used yields the same quantity of product. The technique is also the only polymer-based method that produces the ceramic with a chemical composition identical to silicon carbide.
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