High-Quality and Wafer-Scale Cubic Silicon Carbide Single Crystals

Cubic silicon carbide (3C-SiC) has superior mobility and thermal conduction over that of widely applied hexagonal 4H-SiC. Moreover, much lower concentration of interfacial traps between insulating oxide gate and 3C-SiC helps fabricate reliable and long-life devices like metal-oxide-semiconductor field effect transistors. However, the growth of high-quality and wafer-scale 3C-SiC crystals has remained a big challenge up to now despite decades-long efforts by researchers because of its easy transformation into other polytypes during growth, limiting the development of 3C-SiC-based devices. Herein, we report that 3C-SiC can be made thermodynamically favored from nucleation to growth on a 4H-SiC substrate by top-seeded solution growth technique, beyond what is expected by classical nucleation theory. This enables the steady growth of high-quality and large-size 3C-SiC crystals (2-4-inch in diameter and 4.0-10.0 mm in thickness) sustainable. The as-grown 3C-SiC crystals are free of other polytypes and have high-crystalline quality. Our findings broaden the mechanism of hetero-seed crystal growth and provide a feasible route to mass production of 3C-SiC crystals, offering new opportunities to develop power electronic devices potentially with better performances than those based on 4H-SiC. 3C-SiC shows great potential in fabrication of reliable and long-life devices thanks to its superior mobility, thermal conduction, and low interfacial defects. The difficulties in the growth of 3C-SiC single crystals, however, hampers the device development. By adjustment of the melt surface tension, 3C-SiC are made thermodynamically favored from nucleation to growth on a 4H-SiC hetero-substrate by TSSG, leading to the successful growth of high-quality and wafer-scale 3C-SiC single crystals. The diameter and the thickness are 2-4 inches and 4.0-10.0 mm, respectively.image