Methodology for Improving Temperature Sensing Performance and Thermal Stability of 4H‐SiC JBS Diodes

Abstract In harsh industrial conditions, real‐time and precise temperature monitoring is vital for system safety and efficiency, necessitating high‐precision, durable, and reliable temperature sensors. However, developing sensors that balance high sensitivity with thermal reliability is challenging. Herein, high‐sensitivity and high‐linearity devices for high‐temperature applications are successfully achieved by designing and fabricating 4H‐SiC Junction Barrier Schottky (JBS) diodes. Notably, after 36 h aging at 500 °C, diodes with small active areas achieve a maximum sensitivity ( S ) of 1.65 mV °C ⁻¹ , with only a 6.8% reduction relative to the pristine device, while maintaining high linearity ( R ² > 0.999) over a broad current range (500 µA–2 mA). Specially, large active area diodes achieve the highest S of 2.24 mV °C ⁻¹ among the reported Schottky‐based devices. In addition, a critical aspect is the in‐depth investigation of degradation mechanisms governing the performance degradation after high‐temperature aging over 200–500 °C. The findings identify the presence of a 12 nm‐thick interfacial layer and the significant increase in the interface state density between the titanium layer and 4H‐SiC following aging at 500 °C. These results provide valuable methodologies for improving temperature sensing performance and thermal stability of 4H‐SiC JBS Diodes.