DEPENDENCE OF ELECTRON MOBILITY ON EPI CHANNEL DOPING INGaN MOSFETS

摘要

The field-effect mobility and Hall mobility of electrons in lateral, accumulation-mode GaN MOSFETs have been comparatively studied. The devices were fabricated on three different samples, Sample A consisting of 70 nm n-type (N_D = 5x10~(17) cm~(-3)) GaN and Sample B 0.5 μm unintentionally doped (N_D < 1x10~(16) cm~(-3)) GaN, both on 2 μm undoped Al_(0.35)Ga_(0.65)N grown on the n~+-SiC substrates and Sample C 3 μm unintentionally doped GaN on the sapphire substrate. The maximal field-effect mobilities are 120 cm~2/V-s, 90 cm~2/V-s and 53 cm~2/V-s respectively in the three samples. The Hall mobility is also measured for Samples A & B and reaches a maximal value of 160 cm~2/V-s.