A Study of Inhomogeneous Schottky Diodes on n-Type 4H-SiC
In this study, we performed a statistical analysis of 500 Ni Schottky diodes distributed across a 2-inch, n-type 4H-SiC wafer with an epilayer grown by chemical vapor deposition. A majority of the diodes displayed ideal thermionic emission when under forward bias, whereas some diodes showed ‘double-barrier’ characteristics with a ‘knee’ in the low-voltage log I vs. V plot. X-ray topography (XRT) and polarized light microscopy (PLM) revealed no correlations between screw dislocations and micropipes and the presence of double-barrier diodes. Depth resolved cathodoluminescence (DRCLS) indicated that certain deep-level states are associated with the observed electrical variations.
Robert P. Devaty, David J. Larkin and Stephen E. Saddow
D.J. Ewing et al., "A Study of Inhomogeneous Schottky Diodes on n-Type 4H-SiC", Materials Science Forum, Vols. 527-529, pp. 911-914, 2006