An IGBT has parallel spaced trenches lined with gate oxide and filled with conductive polysilicon gate bodies. The trenches extend through a P− base region which is about 7 microns deep. A deep narrow N+ emitter diffusion is at the top of the trench and a shallow P+ contact diffusion extends between adjacent emitter diffusions. The N+ emitter diffusions are arranged to define a minimum RB′. The trenches are sufficiently deep to define long channel regions which can withstand a substantial portion of the blocking voltage of the device. A second blanket emitter implant and diffusion defines a shallow high concentration emitter diffusion extension at the top of the die for improved contact to the emitter diffusions.