Molecular beam epitaxy of p-type ZnSTe:N and p-n-junction light emitting diodes

p-type doping of ZnS1-xTex alloy with N acceptors has been studied with an idea that an upward shift of the valence band maximum due to Te incorporation could improve p-type doping efficiency. The resistivity was found to be less than 100 Ωcm for the layers with 0.2 < x < 0.3, which are suggested to be p-type from the currentvoltage (I - V) characteristic and the electron-beam induced current. For further characterization, ZnSTe:N/n-ZnS diode structures have been fabricated. It was found that the diode exhibits clear rectification in I - V characteristic, and blue-green electroluminescence probably due to hole injection from the ZnSTe:N layer into the n-ZnS layer. These results indicate p-type conduction in ZnSTe:N, and thus the light-emitting diode operation in the ZnS-based pn-junctions. (copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)