We demonstrate improved electrical and optical properties of indium tin oxide (ITO)/Al reflectors, via SF 6 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 SF 6 and O 2 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 cm 2 and the highest reflectance of 91% at 460 nm, compared to as-deposited and O 2 plasma-treated ITO/Al reflectors.
ASJC Scopus subject areas
- Electrical and Electronic Engineering
- Materials Science(all)
- Chemical Engineering(all)
- Physical and Theoretical Chemistry