Rapid Growth Kinetics, Mechanical Properties and Thermal Stability of Siox Thin Films Grown by Rapid Thermal Low Pressure Chemical Vapor Deposition

ABSTRACTHigh quality SiOx films were deposited onto InP substrates in the temperature range of 350 to 550°C and pressure range of 5 to 15 Torr. Depositions were made by means of rapid thermal low pressure chemical vapor deposition (RT-LPCVD) using oxygen (O2) and 2% diluted silane (SiH4) in argon (Ar) gas sources, with O2:SiH4 gas ratio of 5:1 to 50:1. High deposition rates of 15–50 nm/sec were obtained, providing uniform SiOx layers, with low stresses of −5×109 to −2×109 dyne-cm−2, and thermal stability on post deposition temperatures up to 1000°C. The SiOx films had refractive indexes between 1.44 and 1.50, densities of 2.25 to 2.37grcm−3 and exhibited wet etch rates of 0.2 to 0.8 nmsec.−1 through standard p-etch process. The influence of the various process parameters on the SiOx film properties was examined.