Abstract
This work analyzes the Al 2 O 3 /AlGaN interfacial quality of annealing-free device with multiple fluorine plasma treatments within Al 2 O 3 gate dielectric in HEMT which is expected to have good channel conductivity and high VTH at the same time. Benchmarking with devices that underwent pre-fluorination annealing right after 1 st layer of Al 2 O 3 deposition, unannealed device has about 10 times lower shallow interface trap density (D it ) which resulted in significantly smaller drain leakage current. However, doubled Ultra-violet (UV) -assisted V th hysteresis (ΔV TH ) in bi-directional I D -V G sweep measurement indicates higher concentration of deep-level traps without gate stack annealing.