The present invention relates to an insulated gate bipolar transistor, a technical problem to be solved is to provide an insulated gate bipolar transistor short-circuit robustness (short circuit ruggedness) and a saturation voltage VCE (sat) is optimized in a mutual trade-off relationship is.
The present invention is the first conductivity type drift layer having a surface opposite the second surface of the first surface, the first surface for this purpose; The first mutually spaced apart on a first surface of the conductive type drift layer formed of the second conductivity type well region; A first conductivity type emitter region formed above each of the second conductivity type well region; The second gate electrode between the gate insulating film is interposed in the first-conductivity-type drift layer formed of a conductive type well region; And in the second surface formed on the second conductivity type collector region made of a insulated gate bipolar transistor of the first conductivity type drift layer, it is determined by expression below the saturation voltage Vce of the insulated gate bipolar transistor,

Short-circuit current of the insulated gate bipolar transistor Ice (sat) is determined by equation below,

A common base α _PNP gain of the equation is 0.4 to 0.75.
Here, K is a constant, T is absolute temperature, q is the amount of charge, d is the distance between the drift layer width, Lch is the channel length, Wr is well area, Da is the bipolar diffusion constant, ni is an electronic number, F (d / La ) is a function value, _ns is the spreading factor μ, Cox is the capacitance of the gate insulating film, Z is the number of cells / cm, Vge is the gate voltage, Vth is the threshold voltage.