Electrical characterization of Cu Schottky contacts to n-type GaAsN grown on (311)A/B GaAs substrates

The contact behavior of Cu on n-type GaAsN, grown on (100) and (311)A/B GaAs substrates by chemical beam epitaxy, has been investigated by current–voltage (I–V) and capacitance–voltage (C–V) measurements. Both N incorporation and growth orientation are found to influence the electrical properties of Cu/GaAsN Schottky diodes. The increasing N composition leads to an increase in the ideality factor and Schottky barrier height (C–V), whereas a decrease in the carrier concentration in samples with all adopted growth orientations. Compared with (100) and (311)B samples, the Schottky diodes constructed on (311)A GaAsN epilayer exhibit better performance with ideality factor close to 1 and higher barrier height. The interfacial chemical reaction between metal layer and surface atoms on the growth surface is believed to account for the observations. - Highlights: • The Schottky diodes of Cu on n-type GaAsN with (311)A/B orientations were fabricated. • Effect of N incorporation on the electrical properties of Cu/GaAsN was investigated. • Electrical performance of Cu/GaAsN diode can be tailored by the growth orientation. • The Schottky diodes constructed on (311)A GaAsN exhibit better performance.