Low Specific On-Resistance SOI LDMOS with Non-Depleted Embedded P-Island and Dual Trench Gate

A new silicon-on-insulator (SOI) trench lateral double-diffused metal oxide semiconductor (LDMOS) with a reduced specific on-resistance R_\rm on,sp is presented. The structure features a non-depleted embedded p-type island (EP) and dual vertical trench gate (DG) (EP-DG SOI). First, the optimized doping concentration of drift region is increased due to the assisted depletion effect of EP. Secondly, the dual conduction channel is provided by the DG when the EP-DG SOI is in the on-state. The increased optimized doping concentration of the drift region and the dual conduction channel result in a dramatic reduction in R_\rm on,sp. The mechanism of the EP is analyzed, and the characteristics of R_\rm on,sp and breakdown voltage (BV) are discussed. Compared with conventional trench gate SOI LDMOS, the EP-DG SOI decreases R_\rm on,sp by 47.1% and increases BV from 196 V to 212 V at the same cell pitch by simulation.