CCMP CMC Materials Inc

Cabot Microelectronics Corporation (Nasdaq:CCMP), the world's leading supplier of chemical mechanical planarization (CMP) polishing slurries to the semiconductor industry, announced today that it will host its 2008 Investor Day on Thursday, June 5, 2008, at the Millennium UN Plaza Hotel in New York City, at 1:00 p.m. Eastern Time. During the event, Cabot Microelectronics' Chairman and CEO, William Noglows, and members of the company�s leadership team will discuss the company�s business and strategy. Forward looking information may be discussed during the event, and formal presentations will be webcast. Interested parties may listen to the webcast and view the accompanying slide presentations by visiting the Investor Relations� page of the company�s website, www.cabotcmp.com. The webcast will be archived on the company�s website for 30 days. ABOUT CABOT MICROELECTRONICS CORPORATION Cabot Microelectronics Corporation, headquartered in Aurora, Illinois, is the world's leading supplier of CMP slurries used in semiconductor and data storage manufacturing. The company's products play a critical role in the production of the most advanced semiconductor devices, enabling the manufacture of smaller, faster and more complex devices by its customers. Since becoming an independent public company in 2000, the company has grown to approximately 800 employees on a global basis. The company's vision is to become the world leader in shaping, enabling and enhancing the performance of surfaces, so the company is leveraging its expertise in CMP slurry formulation, materials and polishing techniques developed for the semiconductor industry and applying it to demanding surface modification applications in other industries where shaping, enabling and enhancing the performance of surfaces is critical to success. For more information about Cabot Microelectronics Corporation, visit www.cabotcmp.com or contact Amy Ford, Director of Investor Relations at (630) 499-2600.