Abstract
The device performance of HfO2-based InP MOSFETs with or without Al2O3 interfacial passivation layer and SF6 plasma treatment is investigated. With both Al2O3 interfacial passivation layer (IPL) and SF6 plasma treatment, the transconductance, mobility, and drain current are improved by 50%, 56%, 100% respectively compared with those of a single HfO2 gate oxide layer without SF6 plasma treatment. Also we have investigated SF6 plasma treatment in two ways: 1) 4 minutes treatment from the middle of 5 nm HfO2 oxide, 2) 4 minutes treatment from the top of 5 nm HfO2 oxide. Results show that treatment in the middle introduces more F into the high κ layer and drive current can be further enhanced by over 20% compared with treatment at the top of gate oxide stack.