Ultra-thin quantum wells and fractional monolayer quantum dots of II-IV semiconductors for optoelectronic applicatons

CdTe/ZnTe and CdSe/ZnSe ultra-thin quantum wells (UTQW) with thickness of few monolayers present very strong excitonic emission and can be combined to cover the red-blue spectral range. They are grown by atomic layer epitaxy and the emission from thickness fluctuations can be completely avoided in many cases by choosing the appropriate growth parameters. Submonolayer coverage of CdSe produces fractional monolayer quantum dots (FMQD) which present very narrow blue emission, indicating a high degree of uniformity in size and shape. These UTQWs and FMQDs appear as promising candidates for the elaboration of red to blue light emission devices based on II-VI compounds