CHARACTERIZATION OF HIGHLY EFFICIENT CDTE THIN-FILM SOLAR-CELLS BY LOW-TEMPERATURE PHOTOLUMINESCENCE

Highly efficient CdTe thin film solar cells prepared by close-spaced s ublimation (CSS) method with a,glass/ITO/CdS/CdTe/Cu-doped carbon/Ag s tructure were characterized by low-temperature photoluminescence (PL) measurement. A broad 1.47 eV band probably due to V-Cd-Cl defect compl exes appeared as a result of CdCl2 treatment. CdS/CdTe junction PL rev ealed that a CdSxTe1-x mixed crystal layer was formed at the CdS/CdTe interface region during the deposition of CdTe by CSS and that CdCl2 t reatment promoted the formation of the mixed crystal layer. Furthermor e. in the PL spectra of the heat-treated CdTe after screen printing of the Cu-doped carbon electrode, a neutral-acceptor bound exciton (A(Cu )(0),X) line at 1.590 eV was observed. suggesting that Cu atoms were i ncorporated into CdTe as effective accepters after the heat treatment.