Zinc oxide ultraviolet light-emitting devices : design and fabrication.
Date of Issue2007
School of Electrical and Electronic Engineering
ZnO is one of the semiconductor materials that shows great potential in the fabrication of ultraviolet (UV) light-emitting devices for diverse applications. However, most of the high-quality ZnO thin films are fabricated on expensive lattice-matched sapphire substrates at high temperature (>350 oC). They are not suitable to be manufactured in large quantities and integrated with other silicon-based devices. Besides that, the properties of the ZnO films grown at high temperature are difficult to be modified by post-growth process. Therefore, we proposed the use of filtered cathodic vacuum arc (FCVA) technique to fabricate ZnO thin films and UV light-emitting devices. This is because the FCVA technique has major advantages: 1) The lattice-matching requirement between the substrate and the deposited film is not needed, 2) it is a low-temperature deposition process (<350 oC) due to the high kinetic energies of the deposited species, 3) it allows the fabrication of thin films on large substrates (as large as 6” in diameter), 4) it provides freedom of choices in the target materials for the fabrication of doped and undoped films, since the stoichiometry of the deposited films are independent of that of the targets, 5) it produces microparticle-free thin films, and 6) it is a cost-effective technique to fabricate thin films that is well established and accepted by the industry for mass production.
DRNTU::Engineering::Electrical and electronic engineering