A Bulk Full-Gate SOI-LDMOS Device With Bulk Channel and Electron Accumulation Effect

A novel LDMOS featuring bulk full gate (BFG) with bulk channel and electron accumulation effect, named BFG-LDMOS, is proposed and investigated. The BFG includes bulk gate oxide (BGO) that is inserted in the
${N}$
-drift and the full gate (FG) that is formed by the wide open base transistor (P-body/
${N}$
-drift/P
⁺
). The gate potential is extended in the gate-
${N}$
-drift-drain (GND) region, and thus, the bulk channel of the P-body and electron accumulation effect of the
${N}$
-drift in the source-
${N}$
-drift-drain (SND) region is achieved, which significantly reduces the specific ON-resistance (
${R}_{\text {ON,sp}}$
). In addition, the P-body,
${N}$
-drift, and N
⁺
drain are divided by the BGO, and the P-body/
${N}$
-drift junction (PN1) sustains the breakdown electric field for both sides, which guarantees the breakdown voltage (BV) like conventional LDMOS. The 3-D simulation results indicate that the BV and
${R}_{\text {ON,sp}}$
are 249 V and 2.93
$\text{m}\Omega \cdot $
cm
²
for the proposed BFG-LDMOS, respectively, and the Baliga’s figure of merit (FoM) is high up to 21 MW/cm
²
, which breaks through the silicon limit of the reduced surface field (RESURF).