Analysis And Simulation Of SiC Schottky Barrier Diodes

Silicon carbide as the third generation of semiconductor materials which has obvious advantages in the band gap, breakdown field strength, saturated electron drift velocity and so on, therefore, it has been widely concerned all over the world, the research prospect is really widely. In this paper, the basic characteristics of W/SiC SBD were simulated and analysed.This paper relatively systematically introduces how to use the semiconductor device simulation software of ISE-TCAD to simulate, the software can build and simulate of the different structure of semiconductor devices, and software is highly integrated and powerful. In the paper, by using the software on the W/SiC SBD under different conditions to simulation Ⅰ-Ⅴ characteristics. In order to enhance the in-depth study of the W/SiC SBD, also joined it with comparative simulation study of the P-N junction diode and Au/SiC SBD.Through the W/SiC SBD I-V characteristics research, we draw the following conclusion:1) W/SiC schottky diode has lower positive turn-on voltage. The higher the temperature, the forward current is smaller, and the reverse current and the ideal factor are the greater. Below the room temperature, the reverse current do not tends to saturation with increases of bias voltage.2) In a relative thin epitaxial layer, the change of forward current depends on the substrate concentration, and that of reverse current depends on the epitaxial concentration.3) In a relative thin epitaxial layer and below the substrate concentration, as epitaxial layer thickness increases, the reverse and forward current are all decreased, and the proportion of the former decline is greater.4) At room temperature, after the forward voltage higher than about1900volts, the device begins to breakdown.5) Both Au/SiC and W/SiC have lower turn-on voltage.The work functions of different metal have nearly no impact on the forward current and marked impact on the reverse current.