Bipolar transistor
AssigneeSharp Kabushiki Kaisha
InventorJohn Kevin Twynam
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Abstract
A bipolar transistor of the present invention comprises a collector layer made of an n-type semiconductor and an emitter layer made of an n-type semiconductor provided on this collector layer. A gate layer for injecting p-type carriers (holes) into the emitter layer is provided on the emitter layer. A p-type carrier retaining layer is formed between the collector layer and the emitter layer. The p-type carrier retaining layer temporarily retains the p-type carriers that are injected from the gate layer into the emitter layer and diffused in the emitter layer and reach the p-type carrier retaining layer. The bipolar transistor has a structure whose performance is not influenced by sheet resistance of the base layer, and is able to exhibit a high current gain even in a high-frequency region.
Claims13
A bipolar transistor comprising:
- a collector layer which is made of a first conductive type semiconductor;
- an emitter layer which is made of the first conductive type semiconductor provided on the collector layer;
- a gate layer which is provided on the emitter layer and intended to inject second conductive type carriers into the emitter layer;
- and
- a second conductive type carrier retaining layer which is formed between the collector layer and the emitter layer and temporarily retains the second conductive type carriers that are injected from the gate layer into the emitter layer and diffused in the emitter layer and reach the carrier retaining layer.
Dependencies are inferred from the claim text.