Semiconductor power device
AssigneeKabushiki Kaisha Toshiba
InventorHidetaka Hattori
Life of this patent
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Abstract
A p type base layer is formed in one surface region of an n type base layer. An n type emitter layer is formed in a surface region of the p type base layer. An emitter electrode is formed on the n type emitter layer and the p type base layer. A trench is formed in the n type emitter layer such that extends through the p type base layer to the n type base layer. A trench gate electrode is formed in the trench. The n type base layer has such a concentration gradient continuously changing in a thickness direction thereof that its portion in contact with the p type base layer has a lower concentration than its portion in contact with the p type collector layer, with the p type collector layer having a thickness of 1 μm or less.
Claims14
A semiconductor power device comprising:
- a first base layer containing an impurity of a first conductivity type so as to have a concentration gradient which continuously changes in a thickness direction thereof;
- a second base layer containing an impurity of a second conductivity type formed in one surface region of said first base layer;
- a trench having such a depth as to reach from a surface of said second base layer through said second base layer to said first base layer;
- an emitter layer containing an impurity of said first conductivity type formed in the surface region of said second base layer in such a manner so as to be in contact with said trench;
- a gate electrode formed in said trench;
- a collector layer formed in the other surface of said first base layer, said collector layer contains an impurity of said second conductivity type and has a thickness of 1 μm or less;
- a first main electrode continuously formed on said emitter layer and said second base layer;
- and
- a second main electrode formed on said collector layer.
A semiconductor power device comprising:
- a first base layer containing an impurity of a first conductivity type so as to have a concentration gradient which continuously changes in a thickness direction thereof;
- a second base layer containing an impurity of a second conductivity type formed in one surface region of said first base layer;
- an emitter layer containing an impurity of said first conductivity type formed in a surface region of said second base layer;
- a gate electrode continuously formed at least on said second base layer and said emitter layer;
- a collector layer formed on the other surface of said first base layer, said collector layer contains an impurity of said second conductivity type and has a thickness of 1 μm or less;
- a first main electrode formed on said second base layer;
- and
- a second main electrode formed on said collector layer.
Dependencies are inferred from the claim text.