The Thermochemistry, Toxicity and Growth Properties of Alkylarsine Alternative Sources

Current CVD techniques for III/V semiconductor thin films (OMVPE, Hydride VPE and Gas-source MBE) uses arsine and phosphine as Group-V reactants. However, both these hydrides are extremely toxic, high pressure gases. To develop a safer semiconductor process we have investigated organoarsenic compounds as alternatives to arsine since they have the advantage of being low vapor pressure liquids; e.g., typically, Pvap 250 Torr at 20C. The organoarsenic compounds studied in our work were the alkyl derivatives of arsine, R sub n AsH sub (3-n), where R included methyl, ethyl and butyl-based homologs with varying degrees (n=1- 3) of hydrogen atom substitution.