A Novel IGBT With Voltage-Clamping for Turn-on Overshoot Suppression Under Hard-Switching

A 600 V-rated insulated gate bipolar transistor (IGBT) with improved turn-on transient characteristics is proposed and investigated by simulation. The proposed IGBT features a built-in voltage-clamping structure. The floating
${p}$
-body adjacent to the trench gate is clamped at an appropriately high voltage before turn-on. This slows down the hole accumulation process in the floating
p
-body during turn-on transient, and thus the self-charging displacement current through the gate capacitance is reduced. The increasing rate for the gate voltage (
dV
_GE
/
dt
) is then reduced. As a result, the proposed IGBT achieves a 25% decrease in collector current (
$I_C$
) overshoot and 34% decrease in
dI
_C
/
dt
, when compared with the conventional IGBT with the same turn-on loss (
E
_ON
), at IC = 250 A/cm
²
under hard-switching. Its fabrication process is compatible with conventional trench IGBT.