Papers by Keyword: Fast Epitaxy

Abstract: Homoepitaxial growth of 4H-SiC and characterization of deep levels obtained mainly in the authors’ group have been reviewed. The growth rate has been increased to 24 om/h with keeping very good surface morphology and low trap concentration on 8o off-axis 4H-SiC(0001) by hot-wall chemical vapor deposition at 1650oC. The increased growth rate has resulted in the enhanced conversion of basal-plane dislocations into threading edge dislocations in epilayers. The Z1/2 and EH6/7 concentrations can be decreased to about 1·1012 cm-3 by increasing the C/Si ratio during CVD. Extensive investigation on as-grown and electron-irradiated epilayers indicates that both the Z1/2 and EH6/7 centers may be attributed to the same origin related to carbon displacement, probably a carbon vacancy. Deep levels observed in as-grown and irradiated p-type 4H-SiC are also presented.

Abstract: Generation of stacking faults (SFs) in fast epitaxial growth of 4H-SiC(0001) has been reduced in vertical hot-wall chemical vapor deposition (CVD). 52 µm-thick epilayers with and without SFs are used to investigate impacts of SFs on the performance of Schottky barrier diodes (SBDs). The density, shape and structure of stacking faults have been characterized by cathodeluminescence (CL), photoluminescence (PL) and high-resolution transmission electron microscopy (HR-TEM). These analyses indicate that most (> 75 %) SFs with an 8H structure are generated near the epilayer/substrate interface during CVD. It is also revealed that the SFs cause the lowering of Schottky barrier height as well as the decrease of breakdown voltage.