Vol. 50, Issue 2, pp. 323-330
gallium nitride, molecular beam epitaxy, contacts
We investigated the influence of the In0.17Ga0.83N:Mg contact layer grown by plasma assisted molecular beam epitaxy on the resistivity of p-type Ni/Au contacts. We demonstrate that the Schottky barrier width for p-type contact is less than 5 nm. We compare circular transmission line measurements with a p-n diode current-voltage characteristics and show that discrepancies between these two methods can occur if surface quality is deteriorated. It is found that the most efficient contacts to p-type material consist of In0.17Ga0.83N:Mg contact layer with Mg doping level as high as 2 × 1020 cm–3.