A Physics-based Thermal Model of Nanosheet MOSFETs for Device-Circuit Co-design

A physics-based thermal model is developed to describe the self-heating effects (SHE) on nanosheet MOSFETs. Three stages of transient temperature response due to the anisotropic heat dissipation and asymmetrical temperature distribution are well understood by the thermal RC network model, providing the physical insight into frequency-dependent SHE in AC operation. The proposed model is further implemented into SPICE simulator for high-efficient thermal assessment in circuit level by the flexible BEOL. Layout design in inverter cell correlated with thermal behavior is investigated for static and transient operation downwards 3nm CMOS node. The SHE and thermal-aware reliability in inverter-based ring oscillator are predicted. The thermal model can be used as a device-circuit co-design tool to assess the thermal behavior accurately and efficiently.