Growth of MgxZn1 xO films using remote plasma MOCVD

MgxZn1 xO films were successfully grown on a-plane sapphire (1 1 ¯2 0) substrates by remote plasma enhanced metalorganic chemical vapor deposition (RPE-MOCVD). Diethyl zinc (DEZn), bis-ethylcyclopentadienyl magnesium (EtCp2Mg) and oxygen plasma were used as source materials. By increasing Mg content in the films, the crystal structure was shifted through a mixed state from wurtzite to rock-salt with no significant segregation. Both optical absorption edges and emission peaks of MgxZn1 xO films shifted to the higher energy by increasing the Mg content at room temperature, showing an alloy broadening. The Stokes’ shift of wurtzite MgxZn1 xO alloy films was quantitatively evaluated, resulting in a linear dependence on the absorption edge energy.