CCMP CMC Materials Inc

Cabot Microelectronics Corporation (Nasdaq:CCMP), the leading supplier of chemical mechanical planarization (CMP) slurries to the semiconductor industry, announced today that it will present at the Morgan Stanley Small Cap Chemicals Roundtable in New York, NY, at 1:30 p.m. Eastern Time, on Wednesday, November 30, 2005. Forward looking and other material information may be discussed during the presentation. A copy of the presentation will be available in the Investor Relations section of the company's website, www.cabotcmp.com. About Cabot Microelectronics Cabot Microelectronics Corporation, headquartered in Aurora, Illinois, is the leading supplier of CMP slurries for polishing various materials used in semiconductor manufacturing processes. The company's products play a critical role in the production of advanced semiconductor devices, enabling the manufacture of smaller, faster and more complex devices by its customers. For more information about Cabot Microelectronics Corporation visit www.cabotcmp.com or contact the company at (630) 499-2600.