In order to optimize the growth conditions for ZnCdSe quantum wells (QWs) used as active region in ZnSe-based laser diodes, the influence of different growth parameters on their optical and structural properties have been investigated. To avoid cadmium diffusion and segregation out of the QWs, low-temperature growth is highly desirable. At the same time, to maintain a high crystal quality, migration enhanced epitaxy was used and the ternary compound has been grown as a CdSe/ZnSe sub-monolayer superlattice (SMSL), This growth technique results in a distinct improvement of structural as M-ell as optical properties compared to QWs grown by conventional molecular beam epitaxy. These improvements are accompanied by an increase in the internal quantum efficiency of light emitting diodes. However, up to now, no significant influence on other device characteristics was found. A laser diode based on a SMSL working in continuous wave mode at room temperature could be realized