The red shift of ZnSSe metal-semiconductor-metal light emitting diodes with high injection currents

The reliable n(+)-ZnSSe metal-semiconductor-metal (MSM) blue-green light em itting diodes (LED's) have been fabricated. The contact metal was CuGe/Pt/A u. The current transport mechanisms agree very well with the back to back t unneling diodes. The kink phenomena mere observed in the MSM current-voltag e curves. In the metal-semiconductor interface, the element Zn in ZnSSe can be replaced by Cu results in some acceptor levels as radiative recombinati on centers in the MS interface. The peak wave-length in the LED electrolumi nescent (EL) spectra was strongly dependent on the injection currents from 5 to 40 mA. The peak wavelength and full width at half maximum are 510 and 10 nm, respectively, at 10 mA injection current. When the injection current increases to 15 mA, the peak wavelength shifted to 530 nm due to different recombination centers. Further increasing the injection currents, the peak wavelength shifted slightly to the long wavelength side.