Piezoresistive 4H-Silicon Carbide (SiC) pressure sensor

A novel 4H SiC piezoresistive pressure sensor has been fabricated using a high temperature metallization system. The sensor has been fabricated using 100 mm 4H- SiC Wafers with an double EPI layer. While the top has been etched to form the piezoresistors, the lower Epi-layer is oppositely doped acts as an isolation layer. The formation of the membrane has been performed by a reactive ion etching (RIE) process enabling etch rates of up to 4 µm/min through bulk SiC. The gold-based metallization system is able to withstand high temperatures.