Investigation of the properties of molecular beam epitaxy grown self-organized ZnSe quantum dots embedded in ZnS

ZnSe quantum dots (QDs) were grown on ZnS buffer with 1nm or 100 nm ZnS capping layer. Their optical and electrical properties were investigated using photoluminescence, capacitance-voltage, and deep level transient Fourier spectroscopy. PL peak located at 3.19 eV was observed at low temperature (10K) but the intensity was quenched rapidly with increasing temperature and finally disappeared at about 100 K. Apparent carrier density profile obtained from the C-V measurement exhibited a maximum at the depth of about 100 run below the surface, which was in good agreement,,vith where the single QDs layer was located. The electronic ground state energy level of ZnSe QDs was determined as about 0.11 eV below the conduction band of ZnS by DLTFS.