Chemical-vapor-deposition apparatus and method for reducing particulate contamination in a chemical-vapor-deposition process

摘要

In an epitaxial reactor system using a vacuum pump, which is connected to the reaction chamber (7) by an exhaust line (25), particulate contaminants normally deposit in the exhaust line (25) near its juncture with the reaction chamber (7). When the vacuum pump is isolated from the reaction chamber (7) during a back-filling operation, these contaminants can be entrained in the currents of gas normally produced in the back-filling operation. A removable baffle (33) having the shape of a truncated cone is placed in the exhaust line (25) at its juncture with the reaction chamber (7) to prevent these particles from re-entering the reaction chamber (7).