Approaches to designing thermally stable Schottky contacts to n-GaN

The barrier heights of PdIn, Ni/Ga/Ni and Re Schottky contacts to n-GaN wer e investigated by current-voltage and capacitance-voltage measurements. Ele mental Pd and Ni contacts were also investigated for comparison. In each ca se, the barrier heights were determined as a function of annealing temperat ure. It was shown that stoichiometric PdIn contacts were more stable than P d-only contacts. Similarly, Ni/Ga/Ni diodes were found to be more stable th an Ni diodes. Both the Ni/Ga/Ni contact and the elemental Re contact were s table on short-term annealing up to 700 degrees C.