Improvement of the MOCVD-grown InGaP-on-Si towards high-efficiency solar cell application

The thermal cycle annealing (TCA) for GaAs layer grown on Si substrate (GaA s/Si) increased the photoluminescence (PL) intensity of InGaP epilayer whic h was regrown on the GaAs/Si substrate by about 100 times. The full-width a t half-maximum (FWHM) of double-crystal X-ray diffraction (DXRD) was decrea sed from 313 to 251 arcsec. From the electron-beam-induced current (EBIC) i mage measurements, the defect-related dark spots density (DSD) of the regro wn InGaP layer was reduced by about 30% by using TCA GaAs/Si substrate. Thi s means that TCA treatment for GaAs layer effectively increased the crystal quality of InGaP epilayer regrown on GaAs/Si substrate (InGaP/GaAs/Si). Th e PL intensity of InGaP epilayer was also enhanced due to the passivation o f the residual defect-related nonradiative recombination centres by post-gr owth phosphine (PH3/H-2 = 10%) plasma exposure. (C) 2001 Elsevier Science B .V. All rights reserved.