4H-SiC混合PN/Schottky二极管的研制

报道了4H-SiC混合PN/Schottky二极管的设计、制备和特性．该器件用镍作为肖特基接触金属，使用了结终端扩展（JTE）技术．在肖特基接触下的n型漂移区采用多能量注入的方法形成P区而组成面对面的PN结，这些PN结将肖特基接触屏蔽在高场之外，离子注入的退化是在1500℃下进行了30min．器件可耐压600V，在600V时的最小反向漏电流为1×10-3A/cm2．1000μm的大器件在正向电压为3V时电流密度为200A/cm2，而300μm的小尺寸器件在正向电压为3.5V电流密度可达1000A/cm2．

Fabrication of 4H-SiC Merged PN-Schottky Diodes

The design, fabrication and characteristics of 4H-SiC merged PN-Schottky (MPS) diodes with Ni Schottky contact and junction termination extension (JTE) edge termination are reported. A multiple-energy implantation Al in the surface of the n- drift region below the face-to-face Schottky metal formed pn junctions, which screen the Schottky contact from high electrical, post implantation annealing has been done at 1500℃ for 30min in the ultra-high purity Ar ambient. The devices can block more than 600V reverse voltage and the lowest leakage current at -600V is 1×10-3A/cm2, while the forward current density at 3V is more than 200A/cm2 for 1000μm devices, 1000A/cm2 at 3.5V for 300μm devices.