Properties of delta doped Al_(0.25)Ga_(0.75)N and GaN epitaxial layers

摘要

Delta doping (paused growth doping) was investigated as an alternative to uniformly distributing the dopant in the nitride semiconductor layer.In this work,delta doped layer were produced in MOVPE-grown AlGaN and GaN layers at a susceptor temperature of 1220 degC by turning off the group III precursors (TMG and TMA) and introducing into the reactor a silicon precursor Si_2H_6 (disilane) for a fixed period (pause time) before growth was restarted.The compositional and electrical properties as a function of aluminum content and dopant flux were investigated for nitirde layers on 2 inch c-plane sapphire substrates.