4H-SiC diodes with nickel silicide (Ni2Si) and molybdenum (Mo) Schottky contacts have been fabricated and characterised at temperature up to 400°C. Room temperature boron implantation has been used to form a single zone junction termination extension. Both Ni2Si and Mo diodes revealed unchanging ideality factors and barrier heights (1.45 and 1.3 eV, respectively) at temperatures up to 400°C. Soft recoverable breakdowns were observed both in Ni2Si and Mo Schottky diodes at voltages above 1450 V and 3400 V depending on the epitaxial structure used. These values are about 76% and 94% of the ideal avalanche breakdown voltages. The Ni2Si diodes revealed positive temperature coefficients of breakdown voltage at temperature up to 240°C.

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Physics-based analytical models are seen as an efficient way of predicting the characteristics of power devices since they can achieve high computational efficiency and may be easily calibrated using parameters obtained from experimental data. This paper presents an analytical model for a 4H-SiC Enhancement Mode Vertical JFET (VJFET), based on the physics of this device. The on-state and blocking behaviour of VJFETs with finger widths ranging from 1.6+m to 2.2+m are studied and compared with the results of finite element simulations. It is shown that the analytical model is capable of accurately predicting both the on-state and blocking characteristics from a single set of parameters, underlining its utility as a device design and circuit analysis tool.

Although Silicon Carbide has become the material of choice for high power applications in a range of extreme environments, the interest in creating active chemical sensors requires the development of transistors for additional control circuits to operate in these environments. Despite the recent advances in the quality of oxide layers on SiC, the mobility of inversion layers is still low and this will affect the maximum frequency of the operation for these devices. We present simulation results which indicate that a delta channel, in both n-channel and p-channel structures, is suitable for transistors used with these low level signals. By varying the doping levels of the device we have shown that the optimum delta doping for this application is 1.43x1019 cm-3 for both n and p channel devices. We then show the effects of high temperatures on the delta FET devices and make comparisons with standard SiC MOSFET devices.