Chemical Vapor Deposition of Selective Epitaxial Silicon Layers.

A process of selective epitaxial growth of silicon on an oxide- patterned substrate is developed and the quality of the deposited silicon film is characterized. Good selectivity is achieved in depositing silicon only in the area where the silicon substrate is exposed and not in the areas covered with the oxide. The quality of the deposited silicon film is investigated by SEM and TEM. No dislocations are observed in the samples investigated by TEM. The junction leakage of diodes fabricated on these samples is measured. At a reverse bias of 5 volts, a leakage current density of 30 nA/cm sup 2 is obtained. Precleaning at 1025C for 3 minutes in H sub 2 for the patterned Si substrate was found to be adequate to produce good quality Si films. The size of the facet was found to be reduced by lowering the flow rate of the HCI during the deposition.