Patent ID: 7633122
Filing Date: 2009-12-15
Classification: H01L

Abstract:
1. An insulated gate bipolar transistor device comprising: a semiconductor substrate having a first semiconductor layer of a first conductivity type and a second semiconductor layer of a second conductivity type, which is opposite of the first conductivity type, on a surface of the first semiconductor layer; stripe-shaped trenches formed in a surface of the second semiconductor layer; third semiconductor regions of the first conductivity type in the surface of the second semiconductor layer arranged between every other of the trenches along a direction perpendicular to a longitudinal direction of the trenches so that the third semiconductor regions are alternately arranged with surface regions of the second semiconductor layer existing between the trenches along the surface of the second semiconductor layer; at least one fourth semiconductor region of the second conductivity type selectively formed in at least one surface portion of the third semiconductor regions; a gate electrode in each of the trenches with a gate oxide film interposed between the gate electrode and the respective trench; an emitter electrode in direct contact with the third semiconductor regions and the fourth semiconductor regions; a collector electrode in contact with the first semiconductor layer; and an interlayer insulator film covering the surface regions of the second semiconductor layer to prevent the emitter electrode from contacting the surface regions of the second semiconductor layer.