Observations of inhomogeneity of 3C-SiC layers grown on 6H-SiC substrates by using scanning internal photoemission microscopy

Abstract

3C-SiC layers epitaxially grown on 6H-SiC substrates have been characterized by forming Ni Schottky contacts by scanning internal photoemission microscopy (SIPM). SIPM measurements with a green laser clearly imaged domain patterns consisting of 3C-and 6H-SiC. SIPM with a red laser also revealed that boundaries of the 3C/6H and 3C/3C domains have a lower Schottky barrier. These results are consistent with the current-voltage characteristics. We found that this method is a powerful tool for investigating the inhomogeneity of both crystal quality and electrical characteristics.

(Invited) Two-Dimensional Characterization of Wide-Bandgap Materials and Contact Interfaces by Using Scanning Internal Photoemission Microscopy

“…Thus, the crystal quality of 3C-SiC is not as good as those of 4H-and 6H-SiC. We measured Ni Schottky contacts on p-3C-SiC layers grown on 4H or 6H-SiC substrates (14,15). As shown in Figure 9, the sample surface consists of 3C-SiC domains with a flat top.…”

“…Recently, as wide-bandgap semiconductor materials have been intensively studied for high-power RF and switching electron devices, we reconstructed SIPM for these by using visible lasers. We demonstrated two-dimensional (2-D) characterization of interfacial reaction and surface damages in SiC, GaN, and Oxide-semiconductor Schottky contacts (5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18). We also demonstrated that SIPM is available for semiconductor/semiconductor (S/S) hetero-interfaces and metal-insulator-semiconductor (MIS) interfaces (19,20).…”