Optimization and Experiments of Lateral Semi-Superjunction Device Based on Normalized Current-Carrying Capability

A lateral double diffused metal oxide semiconductor transistor with the semi-superjunction (semi-SJ LDMOS) is optimized based on the normalized current-carrying capability (CC) and experimentally realized in this letter. The device is fabricated based on an optimized equivalent substrate and the semi-SJ is introduced near the source. The semi-SJ increases the local doping concentration in the N regions meanwhile reduces the current path area and carrier mobility, resulting in the variation of CCs before and after the introduction of the semi-SJ. The normalized CC factor η
_C
is proposed to evaluate this variation, with which the minimum specific on-resistance R
_ON,sp
is predicted by the condition of η
_C
= 1. The experiments of the semi-SJ LDMOS exhibit a minimum R
_ON,sp
of 25.5 mΩ·cm
²
under a breakdown voltage V
_B
of 464.3 V. This represents a reduction in R
_ON,sp
by 37.7% when compared with the theoretical R
_ON,sp
of triple RESURF devices.