| 摘要 |
A depleted base transistor with high forward voltage blocking capability includes cathode and anode regions on opposite faces of a semiconductor substrate, a base region therebetween, a rectifying junction for depleting a portion of the base region of majority free carriers and an insulated gate electrode in a trench for modulating the conductivity of the depleted portion of the base region. The regions are formed as a vertical stack of semiconductor layers with the anode region (e.g., P+) as the bottom layer, the buffer region (e.g., N+) on the anode region, the drift region/e.g., N-) on the buffer region, the blocking voltage enhancement region (e.g., N-) on the drift region and the cathode region (e.g., N+) as the top layer on the blocking voltage enhancement region. The trench extends into the substrate at the first face so that a sidewall thereof extends adjacent the cathode region and the blocking voltage enhancement region and defines an interface between these adjacent regions and the interior of the trench which contains the insulated gate electrode. The rectifying junction is provided to deplete at least a portion of the blocking voltage enhancement region so that the P-N diode formed by the stack of anode, buffer, drift, blocking voltage enhancement and cathode regions blocks forward voltages when the insulated gate electrode is maintained at the same potential as the cathode region.
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