The Simulation Study of the SOI Trench LDMOS With Lateral Super Junction

A novel lateral double diffused metal oxide semiconductor (LDMOS) with trench oxide layer, featuring a lateral super junction structure based on the silicon-on-insulator technology is proposed. On the one hand, the lateral super junction combined with the TOL can enhance both the surface and the bulk electric field of the N-drift by the charge compensation. Thus, the breakdown voltage (BV) is improved. On the other hand, the N-Pillar of the lateral super junction provides another current channel for electrons at the forward conduction state, thus the Specific on resistance (R
_on,sp
) is decreased. As the simulation results show, the proposed LDMOS exhibits trapezoidal electric field distribution with BV of 422V, and double electron channels with R
_on,sp
of 30.7 mΩ·cm
²
, thus the figure of merit (FOM) (FOM = BV
²
/R
_on,sp
, Baliga's FOM) of 5.82 MW/cm
²
is achieved, breaking through the silicon limit.