System and method for reducing particles in epitaxial reactors

Abstract

An apparatus and method for reducing particles in reactors. The apparatus includes an enclosure for processing the semiconductor wafers. The enclosure has a wafer handling chamber connected by an isolation gate valve to a processing chamber. Additionally, the apparatus includes pipes for delivering a purge gas into the wafer handling chamber. The purge gas is used to eliminates particles from the enclosure. The apparatus also includes a pilot operated back pressure regulator for regulating the delivery and removal of the purge gas from the enclosure. The apparatus actuates the isolation gate valve in a controlled rate to reduce disturbances from the purge gas entering into the enclosure. The apparatus also includes a Bernoulli wand for lifting and holding a single semiconductor wafer. A dome loaded regulator is used to control the ramp rates of the gas to the Bernoulli wand. The dome loaded regulator is actuated by a pilot gas. The ramp up and ramp down rates of the Bernoulli wand gas can be control by a multitude of restrictions and check valves in the pilot gas line. The apparatus also utilizes ionizers in the purge gas lines entering the wafer handling chamber and load locks. Through the use of an alpha particle emission source in the purge gas line prior to the load lock and wafer handling chamber, the purged gas molecules are ionized. The ionized gas is conductive and therefore discharges all static inside the semiconductor equipment. By removable of the static charge particle and wafers are no longer attracted to each other by electrostatic force. In addition, the apparatus includes means for reducing gas flow turbulence when switching valves within the reactor.