Analytical Model and Design of 4H-SiC Planar and Trenched JBS Diodes

An analytical instrument to design 4H-SiC planar and trenched junction barrier Schottky (JBS) diodes is proposed. The tool is based on a novel full analytical description of the electric field distribution into channel region of the device under reverse bias conditions. The model favorably exploits compact and reversible expressions that take into account all physical and geometrical quantities of the device in order to calculate the electric field at the Schottky contact as well as the reverse diode current, up to the occurrence of the physical limits of the Schottky junction. In contrast to the existing literature, the generality of the model is achieved by the absence of empirical parameters, since all the expressions are analytically derived. Finally, the capability of the analytical model to design generic JBS structures (planar, trenched, or recessed p-type regions) is shown in a step-by-step design process, too. Comparisons with numerical simulations and experimental data evidenced the high validity of the model and showed that it can be used both for high-voltage power diodes and for high switching frequency devices.