TCAD Simulation of Single-Event Transient and Hardening in 700V LDMOS Transistors

This paper presents single-event transient (SET) simulation results for 700V LDMOS, simultaneously, a hardened LDMOS with buried oxide in the drift region is proposed and the saturation characteristic of SET effect is discussed for the first time. Charge collection is used to reveal the response mechanism of SET. By comparing the simulation results from the conventional LDMOS and proposed hardened NiN-LDMOS, the NiN-LDMOS has a lower charge collection of the drain electrode and shorter transient response time. A corresponding comparison was also made according to the different positions of BOX. Results show that with a heavy ion having the linear energy transfer (LET) value of 0.8pC/μm striking vertically into 60μm, the pulse width of the SET signal can be reduced from 24ns of the conventional LDMOS to 4ns of the NiN-LDMOS. Therefore, the hardened NiN-LDMOS can achieve better SET performance than the conventional one under different LET values.