Numerical study on the self-heating effects for vacuum/high-k gate dielectric tri-gate FinFETs. (April 2019)

• Record Type: Journal Article
• Authors: Zhang, Guohe; Lai, Junhua; Zhu, Shengli; Wei, Sufen; Liang, Feng; Yang, Cheng-Fu
• Is Part Of: Microelectronics and reliability. Volume 95(2019)
• Page Start: 52
• Page End: 57
• Publication Date: 2019-04
• Subjects: Vacuum gate dielectric tri-gate FinFET -- High-k FinFET -- Self-heating effect -- Gaseous thermal conductivity -- Trade-offs; Electronic apparatus and appliances -- Reliability -- Periodicals; Miniature electronic equipment -- Periodicals; Appareils électroniques -- Fiabilité -- Périodiques; Équipement électronique miniaturisé -- Périodiques; Electronic apparatus and appliances -- Reliability; Miniature electronic equipment; Periodicals; 621.3815
• DOI: 10.1016/j.microrel.2019.02.006
• Languages: English
• ISSNs: 0026-2714

Abstract

Abstract: The self-heating effects (SHEs) for Vacuum Gate Dielectric (VGD) tri-gate FinFET compared with High-k (HK) Dielectric tri-gate FinFET were investigated here based on 3D numerical electro-thermal TCAD simulation method. Simulation results show that VGD device suffers from a fiercer SHEs than HK device which will result in larger saturation current degradation. It is due to the low thermal conductivity of the gas around the channel which impedes the heat diffusion to the sinks and increases the peak temperature in the hot spot region. The SHEs can be suppressed by increasing the width of gas gap and gas pressure, based on the analysis of the pressure-dependent thermal conductivity of the gas in Nano-gap. However, the increased gas gap width entails the loss of the gate control ability over the channel resulting in the severer short channel effects. Highlights: The SHEs of the VGD tri-gate FinFETs were investigated here compared with high-k dielectric tri-gate FinFETs. VGD tri-gate FinFETs suffer from a fiercer self-heating effect resulting in the performance reliability issue. The pressure-dependent thermal conductivity of gas is modeled for studying the heat diffusion mechanism in nanoscale gap. The SHEs in the device with vacuum gate dielectric can be suppressed by increasing the width of gas gap and gas pressure.