%A Xi Wang(王曦), Hong-Bin Pu(蒲红斌), Qing Liu(刘青), Li-Qi An(安丽琪) %T Shortening turn-on delay of SiC light triggered thyristor by 7-shaped thin n-base doping profile %0 Journal Article %D 2018 %J Chin. Phys. B %R 10.1088/1674-1056/27/10/108502 %P 108502-108502 %V 27 %N 10 %U {https://cpb.iphy.ac.cn/CN/abstract/article_121096.shtml} %8 2018-10-05 %X

A new 4H-SiC light triggered thyristor (LTT) with 7-shaped thin n-base doping profile is proposed and simulated using a two-dimensional numerical method. In this new structure, the bottom region of the thin n-base has a graded doping profile to induce an accelerating electric field and compensate for the shortcoming of the double-layer thin n-base structure in transmitting injected holes. In addition, the accelerating electric field can also speed up the transmission of photon-generated carriers during light triggering. As a result, the current gain of the top pnp transistor of the SiC LTT is further increased. According to the TCAD simulations, the turn-on delay time of the SiC LTT decreases by about 91.5% compared with that of previous double-layer thin n-base SiC LTT. The minimum turn-on delay time of the SiC LTT is only 828 ns, when triggered by 100 mW/cm2 ultraviolet light. Meanwhile, there is only a slight degradation in the forward blocking characteristic.