St. Peters, MO, January 21, 2004 – MEMC Electronic Materials, Inc. (NYSE: WFR) today announced that it has entered into an agreement with IMEC to join its Industrial Affiliation Program (IIAP) that targets the implementation of high-mobility layers and advanced source/drain engineering solutions in scaled planar devices as well as to license IMEC’s strained silicon technology. Strained silicon is a materials solution based on increasing carrier mobility that provides device manufacturers an alternative path to continue scaling beyond the 90nm technology node.

Located in Belgium, IMEC is Europe's leading independent research center in the field of microelectronics and nanotechnology.  By participating in IMEC’s Industrial Affiliation Program, MEMC researchers get the opportunity to work within IMEC in cooperation with researchers from several semiconductor device manufacturers, with the goal of providing solutions for improved device performance by implementing strained silicon (Si) in the transistor channel for scaled planar MOS devices.  In addition, MEMC has also established a licensing agreement to produce blanket strained silicon bulk wafers using IMEC's thin strain relaxed buffer (SRB) technology.

“We are very excited about this new relationship with IMEC,” said Nabeel Gareeb, MEMC’s Chief Executive Officer.  “This puts us in a position to share ideas and insights with our customer-partners concerning the commercialization of strained silicon technology in general. We will use this knowledge and the licensing arrangement to accelerate our in-house development program and rapidly deliver high volume and economical capability.”

Strained silicon bulk wafers using this license will be produced at MEMC’s St. Peters manufacturing facility, with engineering and qualification samples available by May 2004. This is an addition to current samples based on MEMC’s in-house strained silicon development effort.

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MEMC JOINS IMEC’S INDUSTRIAL AFFILIATE PROGRAM AND Licenses Strained Silicon Technology

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“Our thin SiGe SRB technology allows us to build strained Si layers with a similar quality as the more familiar thick SRB approach, achieving 10 times thinner SiGe SRB layers and without the need for an expensive CMP step.

These features make our technology economically attractive,” said Dr. Luc Van den hove, Vice President Silicon Process and Device Technology at IMEC. “The collaboration with MEMC will help to make strained Si available to IC manufacturers.”

About MEMC

MEMC is the world’s largest public company solely devoted to the supply of wafers to semiconductor device manufacturers.  MEMC has been a pioneer in the design and development of wafer technologies over the past four decades.  With R&D and manufacturing facilities in the U.S., Europe and Asia, MEMC enables the next generation of high performance semiconductor devices.

About IMEC

 
IMEC (Inter-university MicroElectronics Center) was founded in 1984 and today is Europe's largest independent research center in the field of microelectronics, nanotechnology, enabling design methods and technologies for ICT systems. IMEC's activities concentrate on the design technology for integrated information and communication systems; silicon process steps and modules, silicon processes; nanotechnology, microsystems, alternative devices and packaging; solar cells; and advanced training in microelectronics. IMEC is headquartered in Leuven, Belgium, and has a staff of more than 1300 people including over 380 industrial residents and guest researchers. Its revenue in 2002 of more than 138M euro was derived from agreements and contracts with the Flemish government, equipment and material suppliers and semiconductor and system-oriented companies worldwide, the EC, MEDEA+ and ESA. News from IMEC is located at http://www.imec.be

This news release contains a forward-looking statement concerning the anticipated availability in May 2004 of engineering and qualification samples of strained silicon. This statement involves certain risks and uncertainties that could cause actual results to differ materially.

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MEMC JOINS IMEC’S INDUSTRIAL AFFILIATE PROGRAM AND Licenses Strained Silicon Technology

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CONTACT:    

MEMC

Janine Orf                                           Jim Donaldson

Director, Investor Relations                Director, Marketing Communications

636-474-5443                                      636-474-5929

jorf@memc.com                                 jdonaldson@memc.com

Michael Polyviou                                Vincent Mayeda

or Scot Hoffman                                 Senior Director

Financial Dynamics                             Loomis Group

212-850-5600                                      909-614-1767

mpolyviou@fd-us.com                       vincent@loomisgroup.com

IMEC

Katrien Marent

Corporate Communication Manager IMEC

Phone: +32 16 281 880

Katrien.Marent@imec.be

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