Growth, processing and characterization of GaN/AlGaN/SiC vertical n-p diodes

Application of SiC substrates instead of the most commonly used sapphire for the heteroepitaxial growth of III-Nitrides offers advantages as better lattice matching, higher thermal conductivity, and electrical conductivity. This namely offers interesting perspectives for the development of vertical III-Nitride devices for switching purposes. For example, an AlGaN/SiC heterojunction could improve the performance of SiC bipolar transistors. In this work, n-type GaN layers have been grown by MOVPE on p-type 4H-SiC substrates using Si doped Al 0.08 Ga 0.92 N or Al 0.3 Ga 0.7 N nucleation layers. They have been characterized with temperature dependent current-voltage ( I-V-T ), capacitance-voltage ( C-V ) techniques and transmission electron microscopy (TEM).

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