Chemical Beam Epitaxial Growth of GaP and InP Using Alternative, Safer Precursors

Phosphorus (P)-based alloys are important for applications in areas including optoelectronics and high speed electronics. Gas phase technologies such as organometallic vapor phase epitaxy (OMVPE) and chemical beam epitaxy (CBE) have traditionally used the extremely dangerous hydride, phosphine (PH3). Less hazardous alternatives need to be found. Three such alternative P-sources are: tertiarybutylphosphine (TBP), bisphosphinoethane (BPE) and trisdimethylaminophosphine (TDMAP). InP and GaP growth results using TBP, BPE, and TDMAP along with a brief discussion of the pyrolysis of these alternative P-sources are presented. InP has been grown using ethyldimethylindium and pre-cracked BPE with excellent surface morphology and strong 10 K photoluminescence with a half width of 4.8 meV. The residual doping level typically was in the high 1015 to low 1016 cm-3 range. GaP has been grown at a substrate temperature of 480°C without precracking the TDMAP.