REAL-TIME MONITORING OF SURFACE-REACTIONS DURING PLASMA-ENHANCED CVD OF SILICON

Reacting silicon surfaces in contact with a SiH4 glow discharge have been studied by a real-time, in situ Fourier-transform infrared attenuated total reflection (FT-IR-ATR) technique. In the early stages of silicon deposition at a substrate temperature of 200 degrees C, SiH2 is the major surface species although (SiH2)(n) chains and SiH3 also exist, while at room temperature, SiH3 and (SiH2)(n) chains are the dominant surface products. At a temperature of -95 degrees C, polymerization reactions among adsorbates proceed on the surface to form polysilanes consisting of (SiH2)(n) chains terminated with SiH3.