Electrical characterization of 6H-SiC enhancement-mode MOSFETs at high temperatures

Linear, small-signal enhancement-mode MOSFETs are fabricated in p-type 6H-S iC. Ion implantation of nitrogen and aluminum are used to form the n(+)-reg ions for the source/drain contacts and the channel-stop, respectively. Dire ct current measurements were performed up to 673 K, revealing a drain-to-so urce saturation current I-DSS of 1.53 mA mm(-1) at V-DS = + 10 V and V-GS = + 9 V, a transconductance in saturation of 0.56 mS mm(-1) at V-GS = + 9 V and a subthreshold slope of 170 mV per decade at room temperature. The exce llent high temperature behavior is demonstrated by an I-ON/I-Off ratio of 1 0(5) at 673 K (10(8) at 303 K) and low leakage currents (<10 pA) below thre shold up to 523 K. The inversion layer mobility of the electrons mu(n) is 4 0 cm(2) V-1 s(-1) at room temperature, having a thermally activated region up to 423 K with maximum of 44 cm(2) V-1 s(-1) before decreasing by phonon scattering. (C) 1999 Elsevier Science S.A. All rights reserved.