Method for fabricating a bipolar transistor
AssigneeInfineon Technologies AG
InventorsKarl-Heinz Müller, Konrad Wolf
Life of this patent
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Abstract
A method for producing bipolar transistors with the aid of selective epitaxy for producing a collector and base. The method includes widening the area of the base either by the isotropic etching of the conductive layer or by the oxidation of the conductive layer and by the subsequent removal of the oxide layer. This widening of the area of the base prevents the occurrence of short-circuits between the emitter and the collector during the subsequent production of the base.
Claims16
A method for fabricating a bipolar transistor, comprising the steps of:
- providing a semiconductor substrate with a conductive region;
- successively applying at least one first insulating layer, at least one conductive layer and at least one second insulating layer to the semiconductor substrate;
- applying a mask;
- carrying out a substantially anisotropic etching of the second insulating layer, a substantially isotropic etching of the conductive layer and a substantially anisotropic etching of the first insulating layer, so that an opening to the conductive region is produced;
- producing a collector and a base, which is connected to the conductive layer, by selective epitaxy in the opening, which is carried out in one process step;
- and
- producing an emitter.
A method for fabricating a bipolar transistor, comprising the steps of:
- providing a semiconductor substrate with a conductive region;
- successively applying at least one first insulating layer, at least one conductive layer and at least one second insulating layer to the semiconductor substrate;
- applying a mask;
- anisotropically etching the second insulating layer and the conductive layer;
- thermally oxidizing the side walls of the conductive layer, so that an oxide layer is produced at the side wall of the conductive layer;
- anisotropically etching the first insulating layer, so that an opening to the conductive region is produced;
- producing a collector by selective epitaxy in the opening;
- etching away the oxide layer on the side wall of the conductive layer;
- producing a base, which is connected to the conductive layer, by selective epitaxy in the opening;
- and
- producing an emitter.
A method for fabricating a bipolar transistor, comprising the steps of:
- providing a semiconductor substrate with a conductive region;
- successively applying at least one first insulating layer, at least one conductive layer and at least one second insulating layer to the semiconductor substrate;
- applying a mask;
- anisotropically etching the second insulating layer and the conductive layer;
- thermally oxidizing the side wall of the conductive layer, so that an oxide layer is produced at the side wall of the conductive layer;
- anisotropically etching the first insulating layer, so that an opening to the conductive region is produced;
- etching away the oxide layer on the side wall of the conductive layer;
- producing a collector and a base, which is connected to the conductive layer, by selective epitaxy in the opening;
- and
- producing an emitter.
Dependencies are inferred from the claim text.