Embedded epitaxial growth of 4H-SiC on trenched substrates and pn junction characteristics

Embedded epitaxial growth has been carried out on 4H-SiC substrates with very narrow and deep trenches. The growth behavior near trenches is investigated under various growth conditions. Epitaxial growth on the sidewalls and at the bottom of trenches was enhanced under a low C/Si ratio which may bring a larger surface diffusion length of reactant species. Pn diodes were fabricated by embedded epitaxial growth on trenched substrates. The crystallographic orientation of the trenches has been found to be important for device fabrication.