Mobility enhancement in heavily doped 4H-SiC (0001), (112¯0), and (11¯00) MOSFETs via an oxidation-minimizing process

Abstract

The effects of a process that minimizes oxidation of SiC on the channel mobility of heavily doped 4H-SiC (0001), (112¯0) and (11¯00) metal-oxide-semiconductor field-effect transistors (MOSFETs) were investigated. High field-effect mobilities were obtained for these MOSFETs even when the acceptor concentration of the p-body (N A) exceeded 1 × 1018 cm-3. The field-effect mobility for the (0001) MOSFETs reached 25 cm2 V-1 s-1 (N A = 1 × 1018 cm-3). The fabricated (11 2¯ 0) and (1 1¯ 00) MOSFETs showed very high channel mobilities of 125 cm2 V-1 s-1 (N A = 1 × 1018 cm-3) and 80 cm2 V-1 s-1 (N A = 5 × 1018 cm-3), respectively.