PHOTOLUMINESCENCE EFFICIENCY STUDY OF WET CHEMICALLY ETCHED CDTE/CD(1-X)NG(X)TE WIRES

Optically active semiconductor wires with lateral extensions between 60 nm and 5 μm based on CdTe/Cd1-xMgxTe quantum well structures have been fabricated by electron beam lithography and subsequent pattern transfer using a wet chemical etching process. Changes of the relative photoluminescence efficiency have been studied by photoluminescence spectroscopy as a function of the wire widths. For narrow wires nonradiative recombination at the wire sidewalls becomes the major recombination mechanism, strongly decreasing the photoluminescence efficiency. We discuss the influence of the exciton diffusion on the photoluminescence efficiency by investigating the wire width dependence of the photoluminescence intensity as a function of temperature and quantum well thickness. High photoluminescence efficiencies are obtained in the case of small diffusion lengths as for example at low temperatures and narrow quantum wells.© 1995 American Institute of Physics.