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.