Improved channel mobility of 4H-SiC n-MOSFETs by ultrahigh-temperature gate oxidation with low-oxygen partial-pressure cooling

摘要

An n-channel metal-oxide-semiconductor field-effect transistor (MOSFET) with high field-effect mobility (mu(FE)) on 4H-SiC (0001) was fabricated using an ultrahigh-temperature gate-oxidation technique, and its improved channel mobility was demonstrated by employing a low-oxygen partial-pressure cooling procedure. The ideal Hatband voltage for n-MOS and p-MOS capacitors and hysteresis-free drain current-gate voltage (I-d-V-g) characteristics were obtained through gate oxidation at 1450 degrees C in 100% O-2 ambient at 1 atm followed by the low-oxygen partial-pressure (1%) rapid-cooling procedure. From the I-d-V-g characteristics, a mu(FE) of 15.8 cm(2) V-1 s(-1) was obtained under the pure O-2 gate-oxidation process. (C) 2018 The Japan Society of Applied Physics