High efficiency InP solar cells from low toxicity tertiarybutylphosphine and trimethylindium by OMVPE

Large scale manufacture of phosphide based compound semiconductor devices by organo-metallic vapor phase epitaxy (OMVPE) typically requires the use of highly toxic phosphine. Advancements in phosphine substitutes have identified tertiarybutylphosphine (TBP) as an excellent precursor for OMVPE of InP. High quality undoped and doped InP films were grown using TBP and trimethylindium. Impurity doped InP films were achieved utilizing diethylzinc and silane for p-type and n-type respectively. 16% efficient solar cells under air mass zero, one sun intensity were demonstrated with V_OC of 871 mV and fill factor of 82.6%. It was shown that TBP could replace phosphine, without adversely affecting device quality in OMVPE deposition of InP, thus significantly reducing toxic gas exposure risk