In this study, a thick Cu block (0.2 mm) with high heat capacitance was fabricated and attached to the source pad of a 1.2 kV Schottky barrier diode wall integrated trench MOSFET (SWITCH-MOS), to improve the ability to withstand a short-circuit while maintaining low on-resistance. Experimental results show that at a low drain-to-source voltage (V dd =100 V), the Cu block can improve the short-circuit endurance time and the short-circuit energy density by 15.1 % and 18.4 %, respectively. TCAD simulation results show that during a long short-circuit transient, Joule heat can be transferred from SiC to a Cu block, thus providing a greater capacity for withstanding a short-circuit.