Mapping of the thermal profile and leakage current behavior in scaled Forksheet FET
摘要
One of the major reliability challenges in next-generation semiconductor devices includes the self-heating effect (SHE) and gate-induced drain leakage (GIDL). These effects are considered a significant roadblock in scaling; hence, it is necessary to address them. The conventional use of silicon dioxide (SiO2) in silicon-on-insulator (SOI) has proven effective in reducing leakage currents. However, SiO2 also tends to impede heat dissipation through the substrate, leading to heat accumulation within the device. Ideally, it is desired that the SOI blocks off the leakage currents selectively, while allowing the flow of heat through the SOI to make the substrate act as a heat sink. The proposed use of boron nitride (BN) as SOI can be a suitable replacement for SiO2, since it has high thermal conductivity while having high electrical resistivity. Our TCAD simulations show 12 and 6% reductions in lattice temperature for N-type and P-type Forksheet Field-Effect Transistors (FSFETs), respectively. The simulation also shows a significant increase of around 27.42% in the electron mobility when BN is used as SOI instead of SiO2. The GIDL current has been reduced by two orders of magnitude. Thus, BN as SOI demonstrates better thermal management and the reliability of FSFET. In addition, we have identified and quantified various heating mechanisms: Joule, Peltier, Thomson, and recombination heats, which are responsible for heat generation and thermal hotspots in the device.