Bipolar transistor with side wall base contacts
Abstract
Abstract A bipolar-type semiconductor device includes a semiconductor substrate on which a collector layer of a first conductivity type, a multilayered structure having a first insulating layer, a first semiconductor layer for connecting a base region, containing an impurity of a second conductivity type, and a second insulating layer, which are sequentially stacked on the semiconductor substrate, in which a first opening is formed in the first semiconductor layer and the second insulating layer, and a second opening having a smaller width than that of the first opening is formed in a position of the first insulating layer corresponding to the bottom portion of the first opening, a second semiconductor layer of the first conductivity type constituting a collector or emitter region formed in the second opening on the impurity-doped layer, a third semiconductor layer of the second conductivity type formed in the first opening, in which a first portion on the second semiconductor layer constitutes a base region, and a second portion adjacent to the first semiconductor layer constitutes a base connecting region, a third insulating layer formed on the base connecting region, and an impurity-doped region of the first conductivity type formed on a surface region of the third semiconductor layer surrounded by the third insulating layer, the impurity-doped region constituting an emitter or collector region.
Inventors
- 👤 Toshio Yamaguchi
Bibliographic Details
Claims Analysis
Total Claims: 7References Cited (Backward Citations)
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