Effects of hydrostatic and uniaxial stress on the Schottky barrier heights of Ga-polarity and N-polarity n-GaN

Measurements of the Schottky barrier heights of Ni/Au contacts on Ga-polarity and N-polarity n-GaN under hydrostatic pressure were reported. It was found that the two different polarities of GaN yield significantly different rates of Schottky barrier height increase with an increase in pressure. Results show that uniaxial stress affects Schottky barrier height only minimally. The changes in barrier height were attributed to a combination of band structure and piezoelectric effects.