Chemical vapor deposition of β-SiC on silicon-on-sapphire and silicon-on-insulator substrates

Abstract

Cubic silicon carbide (β-SiC) films have been grown epitaxially on silicon-on-sapphire (SOS) substrates by chemical vapor deposition. A fresh layer of silicon is first deposited in situ on the SOS substrate at approximately 1050°C. The silicon layer is then carbonized while being heated to 1360°C. The β-SiC layer is grown at 1360°C using silane and propane as sources. β-SiC films can also be grown directly on the SOS substrate without utilizing a fresh silicon layer. Deposition of β-SiC films on silicon-on-insulator (SOI) substrates has also been accomplished with slight modification of the growth parameters described above.The β-SiC films have been characterized by IR reflectance spectroscopy, optical microscopy and electron microscopy. Typical films are 7 μm thick and have a specular surface with some physical features. Electrical transport properties as determined by the Van der Pauw Hall method show the β-SiC films to be p-type while those grown on SOI were n-type. X-ray rocking curve measurements were obtained to determine the crystalline quality of the films. In addition, preliminary optical characterization of the films has been performed.