Effect of Scandium Nitride Film Orientation on Growth and Electrical Properties

Scandium nitride (ScN) is a degenerate semiconductor with great potential as a complementary material to enhance GaN performance in high-power and high-speed electronic applications. Electron mobilities up to 130 cm²/(Vs) have been reported for (100)- ScN on (100)-MgO substrates. The values reported for (111)- ScN, however, are significantly lower. In this work, we investigate the effect of ScN orientation on film growth, composition and electrical properties. A series of thin ScN films were deposited on (111)-, (110)- and (100)-MgO substrates using reactive magnetron sputtering. X-ray diffraction showed that ScN grew with the same orientation as the MgO and crystalline growth and quality was dependent on growth conditions. Secondary ion mass spectroscopy showed that while the variation in the oxygen concentration was negligible, the fluorine and hydrogen concentrations differed between ScN orientations. Hall-effect measurements showed that mobility, carrier concentration, and resistivity were dependent on orientation. In this presentation we will discuss the correlation between the measured electrical properties and the ScN crystallinity and composition.