Cabot Microelectronics to Release Financial Results for Second Quarter of Fiscal Year 2011 on April 28

Cabot Microelectronics Corporation (Nasdaq:CCMP), the world’s leading supplier of chemical mechanical planarization (CMP) slurries and a growing CMP pad supplier to the semiconductor industry, announced today that it will release financial results for its second quarter of Fiscal Year 2011, which ended March 31, 2011, on Thursday, April 28.

The press release, which will be issued prior to market open and available in the Investor Relations section of the company’s website, www.cabotcmp.com, will be followed by a conference call at 9:00 a.m. Central Time.

The conference call will be available via webcast from www.cabotcmp.com, or by phone at 866-362-5158. Callers outside the U.S. can dial 617-597-5397. The conference code for the call is 66882479.

ABOUT CABOT MICROELECTRONICS CORPORATION

Cabot Microelectronics Corporation, headquartered in Aurora, Illinois, is the world's leading supplier of CMP polishing slurries and a growing CMP pad supplier to the semiconductor industry. 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. The company’s mission is to create value by developing reliable and innovative solutions, through close customer collaboration, that solve today’s challenges and help enable tomorrow’s technology. Since becoming an independent public company in 2000, the company has grown to approximately 975 employees on a global basis. For more information about Cabot Microelectronics Corporation, visit www.cabotcmp.com or contact Amy Ford, Director of Investor Relations at 630-499-2600.