Trench-gate-type insulated gate bipolar transistor

摘要

In a trench-gate-type insulated gate bipolar transistor, a current will not flow down to a lower portion of a trench, a high electrical field at the lower portion of the trench is suppressed even if a high voltage is applied, such as at a time of turning off, an increase in on-state resistance and a decrease in breakdown resistance and withstand voltage are suppressed. In the semiconductor device, a plurality of trenches is disposed to reach a rear surface of a drift layer, and a collector layer is disposed at a tip end side in an extended direction of the trenches in a surface layer portion of the drift layer. When a gate electrode is applied with a predetermined voltage, a channel region is formed in a portion of the base layer contacting the trenches, and an electric current flows in the predetermined direction along the trenches.

主权项

1. A semiconductor device comprising:
a semiconductor layer providing a first conductivity-type drift layer; a second conductivity-type base layer disposed at least in a surface layer portion of the drift layer adjacent to a front surface of the drift layer; a plurality of trenches extended in a predetermined direction from the base layer to the drift layer; a gate insulation film disposed on a wall surface of each of the plurality of trenches; a gate electrode disposed on the gate insulation film; a first conductivity-type emitter layer disposed in a surface layer portion of the base layer and at side portions of the plurality of trenches; a second conductivity-type collector layer disposed in the surface layer portion of the drift layer and separated from the base layer; an emitter electrode electrically connected to the emitter layer and the base layer; and a collector electrode electrically connected to the collector layer, wherein the trenches are disposed to reach a rear surface of the drift layer, the collector layer is disposed at a tip end side in an extended direction of the trenches in the surface layer portion of the drift layer, and when the gate electrode is applied with a predetermined voltage, a channel region is formed in a portion of the base layer contacting the trenches and an electric current flows in the predetermined direction along the trenches.