Radiative recombination in ZnTe-CdSe and ZnSe-CdTe heterojunctions |
| |
Authors: | PA Gashin DA Sherban AV Simashkevich |
| |
Institution: | V.I. Lenin State University, Kishinev, USSR |
| |
Abstract: | Electroluminescence in II–VI heterojunctions has been investigated. Three types of ZnTe-CdSe heterojunctions were studied depending on the preparation method: Red diodes obtained by doping with O2, yellow Cu-doped diodes and green undoped heterojunctions. Radiation was observed only in the forward biased junctions. At 80 K the external quantum efficiency is about 1.3% for red ZnTe-CdSe heterojunctions and decreases by one order of magnitude at room temperature. The radiation intensity for the other heterojunctions is the same at 80 K but at 150 K the luminescence disappears. The band diagram and the electroluminescence spectra show that the two-directional injection takes place in the ZnTe-CdSe heterojunctions. The blue electroluminescence for ZnSe-CdTe heterojunctions is due to the injection of hot holes in ZnSe from the high-resistivity layer at the interface and the recombination of these holes with the free electrons through an accepto level at 0.124 eV from the valence band. At 80 K slow periodic current oscillations accompanied by in-phase oscillations of the luminescence have been observed in ZnSe-CdTe heterojunctions. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |