Semiconductor device having a miniature junction area and process for fabricating same

Claim 2

A semiconductor device comprising: a semiconductor substrate having a first semiconductor region of one conductivity type and a second semiconductor region of the opposite conductivity type contained in said first semiconductor region with a p-n junction between said first and second semiconductor regions; an insulating film on one main surface of said substrate and having an opening which exposes portions of the surface of said first semiconductor region and of the surface of said second semiconductor region; a silicon thin film having a first segment covering said insulating film and a second segment in direct contact with the exposed surfaces of said first and second semiconductor regions, and a silicon oxide film produced by the selective oxidation of a portion of said silicon thin film and covering a portion of said p-n junction exposed in said opening of said insulating film; portions of said first and second segments of said silicon thin film that are not selectively oxidized defining first and second electrode wiring paths which are mutually separated by said silicon oxide film, said first and second electrode wiring paths making ohmic contacts with said first and second semiconductor regions, respectively.

Claim 3

The semiconductor device of claim 1, in which said silicon thin film is comprised of polycrystalline silicon and said first and second electrode wiring paths are doped with impurities of said one and said opposite conductivity types, respectively.

Claim 4

The semiconductor device of claim 1, further comprising an insulating layer covering the surface of said first and second electrode wiring paths.

Claim 5

The semiconductor device of claim 2, further comprising an electrical connection to at least one of said first and second electrode wiring paths through said insulating layer.

Claim 6

A semiconductor device comprising a semiconductor substrate of one conductivity type having a first region of the opposite conductivity type therein with a p-n junction between said substrate and said first region, an insulating film on the surface of said substrate and having an opening which exposes a portion of the surface of said first region as well as a portion of the surface of said substrate, a silicon thin film in direct contact with the exposed surface of said first region and extending onto said insulating film, and a silicon oxide film produced by the selective oxidation of said silicon thin film and covering a portion of said p-n junction exposed in said opening of said insulating film and also covering a portion of said insulating film, a portion of said silicon thin film that is not selectively oxidized being patterned and surrounded by said silicon oxide film and making ohmic contact with said first region.

Claim 7

A semiconductor device comprising a semiconductor substrate of one conductivity type having a first region of the opposite conductivity type therein with a p-n junction between said substrate and said first region, an insulating film on the surface of said substrate and having an opening which exposes a portion of the surface of said first region as well as a portion of the surface of said substrate, a silicon thin film in direct contact with the exposed surface of said first region and extending onto said insulating film, and a silicon oxide film produced by the selective oxidation of said silicon thin film and covering a portion of said p-n junction exposed in said opening of said insulating film and also covering a portion of said insulating film, a portion of said silicon thin film that is not selectively oxidized being patterned and surrounded by said silicon oxide film and making ohmic contact with said first region.

Claim 8

A semiconductor device comprising a semiconductor substrate having a first semiconductor region of one conductivity type and a second region of the opposite conductivity type with a p-n junction between said first and second semiconductor regions; an insulating film on the surface of said substrate and having an opening which exposes a portion of said first region, a portion of said second region and a portion of said p-n junction; a silicon oxide film produced by the selective oxidation of a silicon thin film and being in direct contact with the exposed portion of said p-n junction and with portions of the exposed areas of said first and second regions in said opening of said insulating film and on said insulating film; and first and second silicon thin film members left by the selective oxidation of said silicon thin film and mutually separated by said silicon oxide film, said first and second silicon thin film members making ohmic contacts with said first and second regions in said opening, respectively and extending onto said insulating film.

Claim 9

A semiconductor device comprising a semiconductor substrate having a first semiconductor region of one conductivity type and a second region of the opposite conductivity type with a p-n junction between said first and second semiconductor regions; an insulating film on the surface of said substrate and having an opening which exposes a portion of said first region, a portion of said second region and a portion of said p-n junction; a silicon oxide film produced by the selective oxidation of a silicon thin film and being in direct contact with the exposed portion of said p-n junction and with portions of the exposed areas of said first and second regions in said opening of said insulating film and on said insulating film; and first and second silicon thin film members left by the selective oxidation of said silicon thin film and mutually separated by said silicon oxide film, said first and second silicon thin film members making ohmic contacts with said first and second regions in said opening, respectively and extending onto said insulating film.

Claim 10

A semiconductor device comprising a semiconductor substrate of one conductivity type, a first region of an opposite conductivity type formed in said substrate, a second region of said one conductivity type formed in said first region and defining a first p-n junction with said first region, a third region of said opposite conductivity type formed in said second region and defining a second p-n junction with said second region, said first and second p-n junctions extending to the surface of said substrate, an insulating film on said surface of said substrate; an insulating film on said surface of said substrate and having an opening which exposes a portion of said first region as well as a portion of said second region and said third region; a silicon oxide film produced by the selective oxidation of a silicon film, said silicon oxide film being in direct contact with said first and second p-n junctions at said surface of said substrate and with portions of the exposed areas of said first, second, and third regions in said opening of said insulating film, and first, second, and third silicon thin film members not oxidized during the selective oxidation of said silicon thin film and mutually separated by said silicon oxide film, said first, second, and third silicon thin film members respectively making ohmic contact with said first, second, and third regions in said opening.

Claim 11

A semiconductor device comprising a semiconductor substrate of one conductivity type, a first region of an opposite conductivity type formed in said substrate, a second region of said one conductivity type formed in said first region and defining a first p-n junction with said first region, a third region of said opposite conductivity type formed in said second region and defining a second p-n junction with said second region, said first and second p-n junctions extending to the surface of said substrate, an insulating film on said surface of said substrate; an insulating film on said surface of said substrate and having an opening which exposes a portion of said first region as well as a portion of said second region and said third region; a silicon oxide film produced by the selective oxidation of a silicon film, said silicon oxide film being in direct contact with said first and second p-n junctions at said surface of said substrate and with portions of the exposed areas of said first, second, and third regions in said opening of said insulating film, and first, second, and third silicon thin film members not oxidized during the selective oxidation of said silicon thin film and mutually separated by said silicon oxide film, said first, second, and third silicon thin film members respectively making ohmic contact with said first, second, and third regions in said opening.

Claim 12

The semiconductor device of claim 7, further comprising a fourth region of said opposite conductivity type formed in said first region and having a higher impurity concentration than said first region and underlying said first silicon thin film.

Claim 13

The semiconductor device of claim 8, in which said third and fourth regions are formed by the simultaneous introduction of impurities of said opposite conductivity type through said first and third silicon thin films, respectively.