Semiconductor device and driving circuit for semiconductor device
First Claim
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1. A semiconductor device comprising:
- an insulated gate bipolar transistor (IGBT) of a first conductivity type including a first insulated gate transistor of said first conductivity type and a bipolar transistor of a second conductivity type connected between first and second main electrodes; and
a second insulated gate transistor of said second conductivity type configured to short-circuit a base and emitter of said bipolar transistor during an ON state of said second insulated gate transistor, whereina thickness of a gate insulating film of said second insulated gate transistor is so set as to satisfy a prescribed breakdown voltage higher than an element breakdown voltage of said IGBT.
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Abstract
A PMOS transistor (Q2) provided for developing a short circuit between the base and emitter of an N-type IGBT during turn-OFF includes a P diffusion region (5), a P diffusion region (6), and a conductive film (10) and a second gate electrode (15) provided via a gate oxide film (21) on a surface of an N− epitaxial layer (2) between the P diffusion regions (5 and 6). The gate oxide film (21) is formed in a thickness having a gate breakdown voltage higher than the element breakdown voltage of a typical field oxide film and the like.
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Citations
10 Claims
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1. A semiconductor device comprising:
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an insulated gate bipolar transistor (IGBT) of a first conductivity type including a first insulated gate transistor of said first conductivity type and a bipolar transistor of a second conductivity type connected between first and second main electrodes; and a second insulated gate transistor of said second conductivity type configured to short-circuit a base and emitter of said bipolar transistor during an ON state of said second insulated gate transistor, wherein a thickness of a gate insulating film of said second insulated gate transistor is so set as to satisfy a prescribed breakdown voltage higher than an element breakdown voltage of said IGBT. - View Dependent Claims (2, 3, 4, 5, 6, 7)
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8. A driving circuit for a semiconductor device, wherein said semiconductor device comprises:
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an insulated gate bipolar transistor (IGBT) of a first conductivity type including a first insulated gate transistor of said first conductivity type and a bipolar transistor of a second conductivity type connected between first and second main electrodes; and a second insulated gate transistor of said second conductivity type configured to short-circuit a base and emitter of said bipolar transistor during an ON state of said second insulated gate transistor, wherein a thickness of a gate insulating film of said second insulated gate transistor is so set as to satisfy a prescribed breakdown voltage higher than an element breakdown voltage of said IGBT, and said driving circuit comprises; first control signal supply means supplying a first control signal to a gate electrode of said first insulated gate transistor; and second control signal supply means supplying a second control signal obtained in response to said first control signal to the gate electrode of said second insulated gate transistor, wherein said second control signal supply means generates, as said second control signal, a first voltage for turning said second insulated gate transistor off when said first control signal provides instructions to turn said first insulated gate transistor on, and generates a second voltage for turning said second insulated gate transistor on when said first control signal provides instructions to turn said first insulated gate transistor off.
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9. A driving circuit for a semiconductor device, wherein said semiconductor device comprises:
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an insulated gate bipolar transistor (IGBT) of a first conductivity type including a first insulated gate transistor of said first conductivity type and a bipolar transistor of a second conductivity type connected between first and second main electrodes; and a second insulated gate transistor of said second conductivity type configured to short-circuit a base and emitter of said bipolar transistor during a ON state of said second insulated gate transistor, wherein a thickness of a gate insulating film of said second insulated gate transistor is so set as to satisfy a prescribed breakdown voltage higher than an element breakdown voltage of said IGBT, and said driving circuit comprises; a coil having one end applied with a constant voltage and the other end connected to the emitter electrode of said bipolar transistor; control signal supply means supplying a first control signal to a gate electrode of said first insulated gate transistor; and fixed voltage supply means supplying a fixed potential obtained by shifting said constant voltage in the direction of turning said second insulated gate transistor on, to the gate electrode of said second insulated gate transistor.
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10. A driving circuit for a semiconductor device, wherein said semiconductor device comprises:
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an insulated gate bipolar transistor (IGBT) of a first conductivity type including a first insulated gate transistor of said first conductivity type and a bipolar transistor of a second conductivity type connected between first and second main electrodes; and a second insulated gate transistor of said second conductivity type configured to short-circuit a base and emitter of said bipolar transistor during a ON state of said second insulated gate transistor, wherein a thickness of a gate insulating film of said second insulated gate transistor is so set as to satisfy a prescribed breakdown voltage higher than an element breakdown voltage of said IGBT, and said driving circuit comprises; a coil having one end applied with a constant voltage and the other end connected to the emitter electrode of said bipolar transistor; and a control signal supply means supplying the same control signal to a gate electrodes of both said first and second insulated gate transistors.
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Specification