A study of V/Al/Pt/Au and Ti/Al/Pt/Au contacts to n-Al0.3Ga 0.7N/GaN heterostructures is presented. Vanadium was chosen as a potential replacement for Ti because V is expected to form a thermally stable nitride with a low work function. Low-resistance Ohmic contacts are achieved with V/Al/Pt/Au layers after annealing at 650°C, which represents a decrease of 150°C compared to the Ti/Al/Pt/Au counterpart. This contact exhibits two orders of magnitude lower specific contact resistance compared to the Ti/Al/Pt/Au contacts studied in this work when annealed at temperatures less than 800°C, although the specific contact resistance of the Ti/Al/Pt/Au contacts is lower when annealed at higher temperatures. A contact resistance and specific contact resistance of 0.8±0.1mm and (1.4±0.3) ×10-5cm2, respectively, are obtained after annealing at 650°C for 45 s.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)