The effect of high-temperature epitaxial SiC layer growth on the structure of porous silicon carbide

Porous silicon carbide layers obtained by electrochemical etching of 6H-SiC at three anode current densities were investigated. X-ray double- and triple-crystal diffractometry and scanning electron microscopy were used to study the structure of porous SiC layers before and after high-temperature sublimation growth of 6H-SiC epilayers. The density of pores in the structure is found to be independent of the current density in electrochemical etching. The effective diameter of pores increases with increasing current density, resulting in higher porosity of the structure. High-temperature annealing modifies the structure without changing the sample porosity. The structural rearrangement is accompanied by coalescence of single pores and an increase in their diameter