SAN JOSE, CA, October 12, 2006 -- KLA-Tencor Corporation (NasdaqGS: KLAC) today announced it has completed its acquisition of ADE Corporation (NasdaqGM: ADEX). Former ADE stockholders will receive $32.50 per share in cash. The transaction is valued at approximately $474 million.

"We are pleased to welcome ADE as part of KLA-Tencor," stated Rick Wallace, CEO. "The addition of ADE further strengthens our leading inspection and metrology product portfolio and will deliver even more value to our customers."

About KLA-Tencor:

KLA-Tencor is the world leader in yield management and process control solutions for semiconductor manufacturing and related industries. Headquartered in San Jose, Calif., the company has sales and service offices around the world. An S&P 500 company, KLA-Tencor is traded on the NASDAQ Global Select Market under the symbol KLAC. Additional information about the company is available on the Internet at http://www.kla-tencor.com, which website is not part of this press release.

Cautionary Statement Regarding Forward-Looking Statements

This news release contains certain forward-looking statements within the meaning of the "safe harbor" provisions of the United States Private Securities Litigation Reform Act of 1995 and federal securities law. Such forward-looking statements are subject to known and unknown risks and uncertainties that could cause actual results to differ materially from those expressed or implied by such statements. Those statements that make reference to expectations, predictions, beliefs, and assumptions should be considered forward-looking statements. These statements include, but are not limited to, those associated with the strengthening of KLA-Tencor's product portfolio and the delivery of value to KLA-Tencor's customers. These statements involve risks and uncertainties including those associated with the integration of ADE, changes in laws or regulations

and other similar factors. Further information on potential factors that could affect KLA-Tencor's business is contained in its reports on file with the Securities and Exchange Commission, including its Form 10-K for the fiscal year ended June 30, 2005 and its Form 10-Q for the quarter ended March 31, 2006. KLA-Tencor is under no obligation to (and expressly disclaim any such obligation to) update or alter its forward-looking statements whether as a result of new information, future events or otherwise.

Contact:
Meggan Powers
Director Corporate Communications