Metal Au, Ni and Ni/Au contacts on n-GaN were studied for metal contacts for the fabrication of Shottky barrier ultraviolet photodetectors. AES, RBS and current-voltage measurements were used to study the samples. Figure 2 shows the current voltage mechanism of Au, Ni and Ni/Au transparent contacts onto GaN. The Schottky barrier heights of Au contacts were averaged at 0.84 ± 0.02 eV and the ideality factors of 1.7 ± 0.3. Series resistance for these contacts was about 481 ± 4 Ω. Ni contacts onto GaN are dominated by tunneling currents and the leakage current is higher than that of Au. The Schottky barrier heights of Ni contacts were averaged at 0.82 ± 0.04 eV and the ideality factors of 1.9 ± 0.2. Series resistance for these contacts was about 38 ± 1 Ω, far less than that of Au contacts. Ni/Au contacts are annealed at 500 °C for transparency. The leakage current of Ni/Au is two orders of magnitude lower than that of Ni and Au, and the Schottky barrier height was averaged at 2.04 ± 0.01 eV for ideality factors of about 1.6 ± 0.4.
|Consider for a student <br> award (Yes / No)?||No0|
|Level (Hons, MSc, <br> PhD, other)?||other|
|Would you like to <br> submit a short paper <br> for the Conference <br> Proceedings (Yes / No)?||Yes|