High Pressure Plasma (HPP) Deposition of Polycrystalline Silicon Ribbons

Abstract

A high pressure plasma (HPP) deposition process has been characterized for its potential in producing polycrystalline silicon films (ribbons) at low cost. Gas Chromatographic (GC) analysis of HPP deposition reactor effluent gases has been used for characterizing the deposition process. Silicon tetrachloride, trichlorosilane, dichlorosilane, and silane have been evaluated as possible silicon source gases for silicon deposition by HPP. Deposition efficiencies have been determined under various experimental conditions such as rf power of HPP, concentration and flow rate of reactant gases, and substrate temperature. These efficiencies were found to be higher than those obtained by a conventional chemical vapor deposition (CVD) process under all conditions of practical interest. The observed improvements in HPP silicon deposition may be explained using thermodynamics, operative kinetic processes, and deposition mechanisms. Economic potential of the HPP deposition process for producing silicon films appears favorable.