LPCVD conditions generating an intense homogeneous decomposition of silane in the temperature range of 500-630/spl deg/C

In this paper, the transition from homogeneous to heterogeneous kinetic regime is studied in the temperature range from 500 to 630/spl deg/C in a hot wall LPCVD industrial reactor. A hyperbolic-type dependence of the threshold SiH/sub 4/ flow rate (generating a strong homogeneous reaction) as a function of total pressure (in the range of 0.4-1.3 torr) is obtained for the hot wall LPCVD tube in the whole temperature range investigated. For a SiH/sub 4/ flow rate kept constant and higher than a certain value (50 sccm), a weak dependence of the threshold partial pressure on the deposition temperature is obtained for temperatures higher than 550/spl deg/C.