SEMICONDUCTOR DEVICE HAVING TRENCH STRUCTURE AND MANUFACTURING METHOD THEREOF

摘要

A semiconductor device with a trench structure is provided to easily adjust a depletion layer by forming a capacitively coupled conductor. A semiconductor substrate(1) has a plurality of first trenches(5) for forming a cell of an IGBT(insulated gate bipolar transistor) in the center of the substrate. A plurality of second trenches(7) are formed in the outer circumferential part of the semiconductor substrate to improve voltage tolerance. A first insulation layer(18) and a first trench conductor(19) are disposed in the first trench. A second insulation layer(26) and a second trench conductor(27) are disposed in the second trench. A plurality of capacitively coupled conductor layers(29) are formed to capacitively couple the plurality of second trenches.