Modulation of Growth Rate by Electric Current in Liquid-Phase Epitaxy of 4H-SiC

The crystallization of 4H-SiC from Si--C solution in liquid-phase electroepitaxy (LPEE) at 1870 and 2050 °C was investigated. The growth of 4H-SiC was enhanced or suppressed by the application of DC with positive or negative polarity, respectively. By the application of AC, the Joule heating effect was separated from the effect of DC on LPEE. We showed that the effect of DC on LPEE consists of a linear electromigration effect and a quadratic Joule heating effect. The results demonstrate that growth rate can be controlled by adjusting not only temperature but also electric current. The variation of growth rate with temperature in LPEE was also examined, and it was shown that the electromigration effect can be controlled independently of the Joule heating effect by increasing the C concentration in the Si--C solution. At higher temperatures, the growth rate in LPEE can be improved without the enhancement of the Joule heating effect.