White Oak Semiconductor Sandston, Virginia Cleanroom lighting helps maintain the integrity of a controlled environment.

Featured Products: SRT, SRH
Application Type: Industrial Cleanroom

Chrome and steel. Cleanroom suits. Polished tiles and bare walls leading to waffled floors and filtered ceilings. The White Oak Semiconductor manufacturing complex is a high-tech facility that has specific requirements for cleanliness. Once inside, you realize the extent of the exacting standards necessary throughout the facility to maintain the integrity of a cleanroom environment.

White Oak Semiconductor is a joint venture between two electronics giants: Motorola and Siemens. They have combined their knowledge and resources to produce an 800,000 square foot campus situated on 210 acres east of Richmond, Virginia. The complex consists of a state-of-the-art cleanroom wafer fabrication building, a probe assembly and test building, a central utility building, and an industrial water treatment facility, as well as an administration building. Together, they form a fully-integrated microchip manufacturing operation.

White Oak began operation in the fall of 1997 after an aggressive construction schedule that began October 30, 1996. They currently produce the smallest DRAM (dynamic random access memory) chip in the world -- processed on 8-inch silicon wafers, utilizing the latest .25 micron technology.

Lighting Challenge
By definition, a cleanroom is an enclosed area in which the concentration of airborne particles is controlled to specified limits. The number of particles allowed in an area determines its clean-room classification as established by Federal Standard 209E. People and materials entering a cleanroom are subject to strict guidelines, and each component of a cleanroom has to be designed and constructed in a way that will maintain the integrity of the controlled environment.

White Oak's requirements for the lighting included high quality, energy efficient fixtures suitable for different cleanroom class ratings and compatible with a variety of ceiling types. Deliveries that coincided with installation and minimal carton waste were also required to ensure the jobsite complied with special cleanroom construction protocol.

Lighting Solution
Light fixtures for cleanrooms are designed to meet the needs of the various class levels and are designated as "suitable for use" in certain classes. The White Oak Semiconductor facility utilizes approximately 1,000 fixtures marketed under the IntegraSealTM brand by Lithonia Lighting. Nine-hundred-nine of the SRT Series, which are suitable for use in Class 10,000-100,000 cleanrooms, and 103 of the SRH Series, which are suitable for Class 100-1,000, were used. IntegraSeal recessed troffers feature completely sealed and gasketed housings, and lenses with internal prisms for smooth, easy-to-clean surfaces.

Because many cleanroom areas are constructed with 1 1/2 to 2-inch wide ceiling T-bars to support the additional weight of air filters and other components, cleanroom lighting must accommodate them. Standard IntegraSeal fixtures are suitable for T-bars up to 1 1/2 inches wide, however, for the White Oak job, Lithonia custom designed fixtures to fit 2-inch wide T-bars where needed. This customization was a key element of Lithonia's participation in the project.

Several designers and contractors participated in the project in order to adhere to the construction schedule of the complex. To facilitate installation of the lighting, the SRT and SRH fixtures were shipped with lamps installed and a prewired whip. Also, at the request of the contractor, the SRH doorframes were shipped separately to further reduce labor costs. Cleanroom protocol requires that waste be kept to a minimum and that deliveries coincide with installation. Therefore, Lithonia provided job-packed fixtures to minimize carton removal and coordinated staggered shipments to the jobsite.

Henry Becker, Facility Manager at White Oak, fully appreciates the need for every component of a controlled environment to perform as it should. When asked about the lighting, Becker said, "I just take it for granted because it doesn't give me any problems. It does what it's supposed to do."

Conclusion
Microchip technology continues to advance at a rapid pace due to the commitment of industry leaders such as Motorola and Siemens. The flexibility and responsiveness demonstrated by Lithonia Lighting on the White Oak job are indicative of the criteria necessary for fast-track demanding projects.