The characteristics of nitride-based Schottky diodes with a single low-temperature GaN nucleation layer and multiple MgxNy/GaN nucleation layers were presented. With multiple MgxNy/GaN nucleation layers, it was found that reverse leakage current became smaller by 6 orders of magnitude than that with a conventional low-temperature GaN nucleation layer. This result might be attributed to the significant reduction of threading dislocations and threading dislocation-related surface states. From the double crystal X-ray diffraction and photoluminescence analyses, it was found that the introduction of multiple MgxNy/GaN nucleation layers could be able to reduce the edge-type threading dislocations effectively. Furthermore, it was also found that effective Schottky barrier height increased from 1.07 to 1.15eV with the insertion of the multiple MgxNy/GaN nucleation layers.

Dislocation Reduction in Nitride-Based Schottky Diodes by using Multiple MgxNy/GaN Nucleation Layers. K.H.Lee, P.C.Chang, S.J.Chang, Y.K.Su, Y.C.Wang, C.L.Yu, C.H.Kuo: Thin Solid Films, 2010, 518[10], 2839-42