Tailored Polycrystalline Substrate for SmartSiC^TM Substrates Enabling High Performance Power Devices

Abstract

Silicon Carbide (SiC) Power Devices have emerged as a breakthrough technology for a wide range of applications in the frame of high-power electronics, notably in the 600 to 3,300V. The last decades have shown a continuous and impressive improvement in both 4H-SiC wafer size and quality. Nevertheless, the availability of such wafers remains a challenge for the SiC power industry. In the last three years, Soitec has successfully adapted the Smart Cut™ technology to Silicon Carbide, resulting in the integration of a thin layer of high quality 4H-SiC on an ultra-low resistivity 3C p-SiC handle wafer. The so-called SmartSiC™ offers a drastic yield improvement for the whole industry thanks to the multiple times re-use of the 4H-SiC donor wafer, as well as an improvement of the device’s electrical performance, especially thanks to the ultra-low resistivity polycrystalline silicon carbide (p-SiC). The latter being specially developed to enhance the new SmartSiC™ substrate capabilities. In this paper, we present the work done by Mersen and Soitec to tailor the p-SiC properties, and thus the SmartSiC™ ones including such material.