5 - Metal oxide-based LED and LASER: Theoretical concepts, conventional devices, and LED based on quantum dots

Abstract

Different metal oxides, which encompass the profuse materials on the earth’s crust, are materials used in conventional ceramics. Metal oxides are patently dissimilar from traditional inorganic materials in terms of their material design, charge transportation, defect states, electronic structure, thin-film processing, and optoelectronic characteristics. Recently, new advancements in metal oxide materials for optoelectronic devices and their enhanced properties have been achieved with the addition of newly conducting oxides like CuO@ZnO, SiO2-p-CuO/n-Si, CuO-based QDLEDs, oxide–metal oxide-based organic light-emitting diodes (OLEDs), monolithically integrated Sb-III laser diodes fabricated on miscut, optically pumped quantum dot lasing and integrated optical cavities, and LASER using the L-ITO@DFB cavity CdTexSe(1-x), SQDs, QLEDs. The stated survey includes the universality and inimitability of different metal oxides and quantum dots for LED and LASER fabrication, where their performances have been highlighted. ZnO has been considered an ideal metal oxide for UV and blue LED due to its high excitation energy and large band gap. Furthermore, ZnO would also be a suitable metal oxide for short-wavelength laser diodes and UV and blue laser applications due to its high binding energy and broad band gap. In addition, a solution process-based CuO thin film is introduced as a new hole injection layer (HIL) for quantum dot light-emitting diodes (QDLEDs). Overall, it has been observed that metal oxides, especially quantum dot-based devices, show enhanced performances as compared to those of conventional devices.