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

A drain-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 SiO
₂
and HfO
₂
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 HfO
₂
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 Ω·um
²
, and a large figure of merit (V
_BD
²
/R
_{ON_sp}
) of 11.46 W/um
²
, which are greatly improved HV performance over other devices. This indicates that the HfO
₂
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 × 10
^-4
A/,um, low OFF-state current (I
_OFF
) of 6.54 × 10
^-10
A/,um, and small subthreshold swing (SS) of 65.54 mV/decade are observed for the optimized HfO
₂
-DeFinFET. Consequently, the proposed design with the high-k field plate can be a pathway to realize HV DeFinFETs for SoC technology.