GaAs solar cells with conversion efficiencies as high as 14percnt; at AM1 have been grown by the GaCl/AsH3hydride technique. Thin (sim;200 Aring;) layers of InGaP were used to passivate the GaAs top surface. We observe a 70hyphen;fold increase in photoluminescence intensity of the GaAs after passivation, which is consistent with a lowering of the GaAs surface recombination velocity from gsim;106to 104cm/sec. Shorthyphen;circuit current densities (Jsc) as high as 22 mA/cm2and openhyphen;circuit voltages as high as 0.96 V were observed. (If achieved together, those values would yield an efficiency of almost 18percnt;.)Vocwas observed to increase directly withphyphen;layer thickness (t), whereasJscdecreased directly witht. The efficiency also increased as the zinc doping was decreased.
展开▼
