To enable driving at a high withstand voltage and a large current, increase latchup immunity, and reduce ON resistance per unit area in an IGBT, a trench constituted by an upper stage trench and a lower stage trench is formed over an entire wafer surface between an n+ emitter region and a p+ collector region, and the trench is filled with a trench-filling insulating film. Thus, a drift region for supporting the withstand voltage is folded in the depth direction of the wafer, thereby lengthening the effective drift length. An emitter-side field plate is buried in the trench-filling insulating film to block a lateral electric field generated on the emitter side of the trench-filling insulating film, and as a result, an electric field generated at a PN junction between an n− drift region and a p base region is reduced.
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机译:为了能够在高耐压和大电流下驱动,提高闩锁抗扰度并降低IGBT中的每单位面积的导通电阻,由上级沟槽和下级沟槽构成的沟槽形成在整个晶片表面之间。 n + Sup>发射极区和ap + Sup>集电极区,并用沟槽填充绝缘膜填充沟槽。因此,用于支撑耐压的漂移区域在晶片的深度方向上折叠,从而延长了有效漂移长度。发射极侧场板掩埋在沟槽填充绝缘膜中,以阻挡在沟槽填充绝缘膜的发射极侧产生的横向电场,其结果是,在n之间的PN结处产生的电场- Sup>漂移区和ap基极区减小。
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