Mobility enhancement in heavily doped 4H-SiC (0001), (1120), and (1100) MOSFETs via an oxidation-minimizing process

Abstract

Abstract The effects of a process that minimizes oxidation of SiC on the channel mobility of heavily doped 4H-SiC (0001), (112̄0) and (11̄00) 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 × 10 18 cm −3 . The field-effect mobility for the (0001) MOSFETs reached 25 cm 2 V −1 s −1 ( N A = 1 × 10 18 cm −3 ). The fabricated (11 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mover accent="true"> <mml:mrow> <mml:mn>2</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>¯</mml:mo> </mml:mrow> </mml:mover> </mml:math> 0) and (1 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mover accent="true"> <mml:mrow> <mml:mn>1</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>¯</mml:mo> </mml:mrow> </mml:mover> </mml:math> 00) MOSFETs showed very high channel mobilities of 125 cm 2 V −1 s −1 ( N A = 1 × 10 18 cm −3 ) and 80 cm 2 V −1 s −1 ( N A = 5 × 10 18 cm −3 ), respectively.