P-N AND P-N-P JUNCTION ARRAYS IN CUINSE(2) CRYSTALS - CATHODOLUMINESCENCE AND CAPACITANCE STUDY

Microstructures in p-CuInSe2 single crystals tailored by a strong elec tric field have been studied using the methods of local cathodolumines cence, electron-beam-induced current (EBIC), capacitance-voltage (C-V) characteristics, and deep-level transient spectroscopy (DLTS) spectra , and have been considered through a prism of elemental stability in t he ternary compound. The shortest-wavelength cathodoluminescence radia tion ((h) over bar omega(m) = 1.023 eV) is observed from a layer of n type, the longer-wavelength radiation ((h) over bar omega(m) = 1.01 an d 0.973 eV), from p-type areas, both a p layer and the p-bulk crystal. The analysis of the spectra has allowed us to attribute experimental features to optical transitions associated with donor and acceptor lev els of V-Cu, V-Se, Cui point defects. The capacitance study by the C-V characteristics and DLTS spectra as well as the EBIC test have shown formation of diode-type or transistor-type microstructures. The \N-D-N -A\ concentration profile, thermal activation, and emission energies o f 22-25 and 170 meV, and a capture cross-section sigma(h) = 2 x 10(-19 ) cm(2) of the deep donor level have been obtained for the microstruct ures. The two-stage resistive model has been considered for p-n and p- n-p junction formation. (C) 1997 American Institute of Physics.