Chemical Vapor Deposition of Epitaxial Silicon from Silane at Low Temperatures: II. Plasma Enhanced Deposition

Abstract

The deposition of epitaxial silicon films at temperatures from 600°–800°C by both very low-pressure chemical vapor deposition (VLPCVD) and plasma-enhanced chemical vapor deposition (PECVD) has been examined. The VLPCVD deposition process was described in detail in Part I of this series. Plasma enhancement of the deposition process led to enhanced growth rates without a change in the apparent activation energy, and the mild ion bombardment (plasma) exposure during deposition introduced no observable stacking faults or dislocations. The effects of plasma power, argon dilution, and hydrogen dilution on the efficiency of the plasma deposition enhancement with very low total pressures (1–10 mtorr) were examined. Under the conditions employed here, power coupling efficiency is relatively low and growth rate enhancement does not become significant until temperatures are below 700°C. The implications of these observations for future PECVD applications for epitaxial deposition are discussed. © 1989, The Electrochemical Society, Inc. All rights reserved.