Electrophoretic deposition of CdSe@CdZnS–ZnS multi core–shell QDs for quantum efficiency control of InGaN/GaN MQW LEDs

Abstract

CdSe@CdZnS–ZnS multi core–shell quantum dots (MCSQDs) were deposited on fluorine doped tin oxide (FTO) glass substrates as well as InGaN/GaN MQW LEDs by electrophoretic deposition (EPD). The as synthesized QDs having particle size 6 nm with emission peak at 596 nm. The number of QDs deposited on the substrate increased with prolonged deposition times and applied voltages. Lower voltage (20 V) deposition on FTO glass showed linearity in photoluminescence (PL) peak intensity. The green emitted InGaN/GaN MQW LEDs showed the dual PL emission after EPD of CdSe@CdZnS–ZnS MCSQDs. Surface roughness and PL peak intensity nearby 596 nm showed a reverse relationship in QDs deposited InGaN/GaN MQW LEDs.