MENLO PARK, CA, July 29, 2004 — Ultra Clean Holdings, Inc. (Nasdaq: UCTT), a developer and supplier of critical subsystems for the semiconductor capital equipment industry, focusing on gas delivery systems, today announced plans to construct a manufacturing facility in China.

Scheduled for a Q1, 2005 opening, the facility is strategically located in Kangqiao Technology Park, Pudong, Shanghai.  The facility will have a cleanroom with class 100 and class 1000 areas for the welding and assembly of gas delivery systems and other major modules of the semiconductor process tool. 

According to Clarence Granger, President and Chief Executive Officer, "It is clear to us that to capture additional outsourcing opportunities in subassembly manufacturing and integration, we need to locate where those opportunities currently exist and are likely to expand.  We believe that opening this facility in Shanghai will allow us to serve current customers more effectively, and position us well to penetrate new customers in the Asian market.”

About Ultra Clean Holdings, Inc.
Ultra Clean Holdings, Inc. is a developer and supplier of critical subsystems for the semiconductor capital equipment industry, focusing on gas delivery systems.  Ultra Clean offers its customers a complete outsourced solution for gas delivery systems, improved design-to-delivery cycle times, component neutral design and manufacturing and component testing capabilities.  Ultra Clean’s customers are primarily original equipment manufacturers of semiconductor capital equipment.  The Company is headquartered in Menlo Park, California.  Additional information is available at www.uct.com.

Safe Harbor Statement
The foregoing information contains, or may be deemed to contain, "forward-looking statements" (as defined in the U.S. Private Securities Litigation Reform Act of 1995) which reflect our current views with respect to future events and performance.  We use words such as "believe," "likely", "position", and similar expressions to identify these forward-looking statements.  All forward-looking statements address matters that involve risks and uncertainties. Accordingly, you should not rely on forward-looking statements, as there are or will be important factors that could cause our actual results, as well as those of the markets we serve and operate in, levels of activity, performance, achievements and prospects to differ materially from the results predicted or implied by these forward- looking statements. These risks, uncertainties and other factors include, among others, those identified in "Risk Factors," "Management's Discussion and Analysis of Financial Condition and Results of Operations" and elsewhere in our S-1 registration statement and Form 10-Q filed with the Securities and Exchange Commission.  Ultra Clean Holdings, Inc. undertakes no obligation to publicly update or review any forward-looking statements, whether as a result of new information, future developments or otherwise.