High stability of CdZnSSe active layers in ZnSe‐based laser diodes by introducing strain‐compensating barrier layers

Abstract

AbstractA series of four similar laser structures with an emission wavelength of 520 nm was grown by molecular beam epitaxy. The difference was the alternating implementation of an additional 5 nm thick ZnSSe layer with a high sulfur composition of 25% neighboring the quantum well on the n‐, p‐ or n‐& p‐side. A high stability of the CdZnSSe active layer was observed by introducing such a kind of strain compensating barrier layers. In lifetime measurements a large improvement was noticed by the p‐ and n‐ & p‐side barrier layers. With respect to the strain compensating effect of only one barrier layer, the p‐side layer is more effective than the n‐side one. It is assumed that the p‐side barrier layer acts not only as strain‐compensating layer, but also as blocking layer against the Cd diffusion into the p‐doped layers. A lifetime extension of one order of magnitude could be achieved. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)