We demonstrate improved electrical and optical properties of indium tin oxide (ITO)/Al reflectors, via SF6 plasma treatments, for vertical-type GaN light emitting diodes. A 200 nm thick ITO film was deposited and annealed at 650°C to obtain ohmic contacts with p-GaN, after which SF6 and O2 plasma were applied on ITO before the Al deposition to effectively increase the work function of ITO and decrease the roughness of the ITO surface. The SF6 plasma-treated ITO/Al reflector showed the lowest specific contact resistance of 9.83× 10-4 ω cm2 and the highest reflectance of 91% at 460 nm, compared to as-deposited and O2 plasma-treated ITO/Al reflectors.
ASJC Scopus subject areas
- Chemical Engineering(all)
- Materials Science(all)
- Physical and Theoretical Chemistry
- Electrical and Electronic Engineering