Luminescence properties of CdS quantum dots on ZnSe

The luminescence properties of self-assembled CdS quantum dots (QDs) were s tudied. CdS QD structures formed on ZnSe buffer layers without capping laye rs showed intense photoluminescence (PL). The PL peak position could be con trolled by changing the amount of CdS deposited. Introduction of the cappin g layer enhanced the PL intensity. The buffer layer material selected also affected the luminescence properties of the CdS QDs, and brighter PL with t he higher transition energy was observed by replacing the ZnSe buffer layer with ZnSSe. A light emitting diode structure based on CdS QDs sandwiched i n the pn junction of ZnSe was fabricated and bright blue or green luminesce nce from current injection was observed at 77 K as well as at room temperat ure. (C) 1999 American Vacuum Society. [S0734-211X(99)03105-4].