Indium tin oxide (ITO) (260 nm) and Ni (5 nm)/Au (10 nm) films were deposited onto glass substrates, p-GaN layers, n+ -InGaN/GaN short-period-superlattice (SPS), n++ -SPS and nitride-based green light-emitting diodes (LEDs). It was found that ITO could provide us an extremely high transparency (i.e., 95% at 520 nm). It was also found that the 1.03 × 10-3 ωcm2 specific contact resistance of ITO on n++ -SPS was reasonably small. Although forward voltage of the LED with ITO on n++ -SPS upper contact was slightly higher than that of the LED with Ni/Au on n++ -SPS upper contact, 20 Ma output power and external quantum efficiency of the green LED with ITO on n ++ -SPS upper contact could reach 4.98 m W and 8.2%, respectively, which were much larger than those observed from the green LED with Ni/Au on n++ -SPS upper contact. The reliability of ITO on n++ -SPS upper contact was also found to be reasonably good.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering