Capacitance analysis of Al _0.25 Ga _0.75 N/GaN heterostructure barrier varactor diodes

Abstract

) layers with respective thicknesses of 500 nm and 1 µm to form the top and the bottom ohmic contacts. At room temperature, the C-V characteristics show a maximum capacitance C max at approximately -1.8 V because of the induced piezoelectric field within the heterostructure, and the I-V characteristics show an increase in leakage current below -1.5 V and above 0.5 V.

Status and Prospects of High-Power Heterostructure Barrier Varactor Frequency Multipliers

“…As noted above, HBVs were initially realized in the AlGaAs/GaAs material system, which is lattice matched over the entire Al x Ga 1-x As range. In addition, the AlGaN/GaN material system, with its superior thermal conductivity and large heterostructure band offsets, has been explored [46], [47], in addition to the low-bandgap system AlSb/InAs [48]. However, improved performance was achieved using the more mature InGaAs/InAlAs semiconductor compound alloy because of its higher mobility and moderate bandgap offset.…”