Growth Uniformity of Epitaxy Silicon Grown at 200 °C Using 60 MHz Very High Frequency Plasma Enhanced Vapor Phase Epitaxy

Abstract

We studied effect of film growth uniformity for low temperature silicon epitaxy using 60 MHz Very High Frequency Chemical Vapor Deposition (VHF PECVD). High quality, high growth rate epitaxy silicon can be obtained at low temperature using VHF PECVD. The major source of the film uniformity appears to be voltage distribution across the plasma electrode, and the uniformity could be improved by using double symmetric power feed using shielded cable. Use of double symmetric power feed around the center of the plasma electrode greatly reduced the voltage non-uniformity, and the shielded cables made stable power transport. As a result, the film thickness uniformity was improved from 21% to 5.8% with our modified reactor configuration.