Thermal Characteristics Enhancement of Drain-Extended FinFETs for System on Chip Applications With Dual High-k Field Plates

Abstract

In this paper, we analyze the electrical and thermal characteristics through Drain-Extended Fin Field-effect Transistor (DeFinFET) using separated high-k field plates. In this article, we first compare the structure using silicon dioxide (SiO2) as the field plate near the drain with that using aluminum oxide (Al2O3). The maximum lattice temperature (Tmax) in the hafnium oxide (HfO2)/SiO2 structure is 391.953 K under the same current condition, whereas Tmaxis reduced to 360.941 K in the HfO2/Al2O3 structure, indicating improved thermal management. Similarly, the thermal resistance (Rth) is reduced by 8.73% in the Al2O3 based structure, indicating improved thermal characteristics. Heat flux analysis results show that 60.1% of the generated heat is dissipated through the extended drain region, which identifies the heat dissipation path of the device. And when the length of the Al2O3 field plate in the HfO2/Al2O3 structure was changed to 20 nm, 40 nm, 60 nm, and 80 nm, the Rth of the 80 nm configuration was found to achieve the best thermal performance with a thermal resistance of 217.091 μm · K/mW. In addition, in this structure, the drain current reduction rate due to SHE was the lowest at 12.1%, and excellent breakdown voltage (VBD) was derived because the electric field was not concentrated at the field plate junction near the drain. Consequently, the proposed device has potential application to high voltage (HV) System on Chip (SoC).