High-Voltage Drain-Extended FinFET With a High-k Dielectric Field Plate

Abstract

Adrain-extended (De) FinFET (DeFinFET) with a high-k dielectric field plate is proposed for high-voltage (HV) system-on-chip (SoC) applications at 10-nm CMOS technology nodes. Conventional DeFinFETs without the dielectric field plate and DeFinFETs with SiO2 and HfO2 field plate are investigated by varying the length (L-EXT) and the doping concentration (N-EXT) of the fin extension and the thickness (T-FOX) of the dielectric field plate. The optimized device with the HfO2 field plate has a high breakdown voltage (V-BD) of 8.56 V, a low specific ON-state resistance (R-ON_sp) of 6.40 Omega.mu m(2), and a large figure of merit (V-BD(2)/RON_sp) of 11.46 W/mu m(2), which are greatly improved HV performance over other devices. This indicates that the HfO2 field plate can effectively address the tradeoff between V-BD and R-ON_sp. In addition, the excellent electrical characteristics such as high ON-state current (I-ON) of 3.07 x 10(-4) A/mu m, low OFF-state current (I-OFF) of 6.54 x 10(-10) A/mu m, and small subthreshold swing (SS) of 65.54 mV/decade are observed for the optimized HfO2-DeFinFET. Consequently, the proposed design with the high-k field plate can be a pathway to realize HV DeFinFETs for SoC technology.