Semiconductor device and method of making the same

Claim 2

A semiconductor device comprising: a semiconductor substrate, at least an impurity-diffused region formed on a part of a principal face of said substrate, an insulation film formed on said substrate with an opening to expose said impurity-diffused region therefrom, at least a polycrystalline semiconductor layer formed on said insulation film to surround said opening on said impurity-diffused region, and a conductive film formed to connect said impurity-diffused region and said polycrystalline semiconductor layer surrounding said opening.

Claim 3

A semiconductor device in accordance with claim 1, wherein said conductive film is of a metal film to be selectively deposited on semiconductor surface.

Claim 4

A semiconductor device in accordance with claim 1, wherein said conductive film is a tungsten film.

Claim 5

A semiconductor device in accordance with claim 1, wherein said conductive film is a tungsten film of low-pressure CVD deposition.

Claim 6

A semiconductor device in accordance with claim 1, wherein said at least a polycrystalline semiconductor layer comprises a first polycrystalline semiconductor layer and a second polycrystalline semiconductor layer with a" second insulation film formed inbetween.

Claim 7

A semiconductor device in accordance with claim 5, wherein said first polycrystalline semiconductor layer and said second polycrystalline semiconductor layer are polycrystalline silicon layers.

Claim 8

A semiconductor device in accordance with claim 5, wherein said first polycrystalline semiconductor layer and said second polycrystalline semiconductor layer are polycrystalline silicon layers, and said conductive film is a tungsten film.

Claim 9

Method for making the semiconductor device comprising the steps of: . forming an insulation film on a semiconductor substrate, forming a polycrystalline semiconductor layer on said insulation film, forming at least one complex opening by boring through said polycrystalline semiconductor layer and further underlying insulation film thereby exposing a surface of said substrate, introducing an impurity through said complex opening into said substrate to form an impurity-diffused region in said substrate, and selectively forming a conductive film on said impurity-diffused region and on said polycrystalline layer, to connect said impurity-diffused region and said polycrystalline film therewith.

Claim 10

Method for making the semiconductor device comprising the steps of: . forming an insulation film on a semiconductor substrate, forming a polycrystalline semiconductor layer on said insulation film, forming at least one complex opening by boring through said polycrystalline semiconductor layer and further underlying insulation film thereby exposing a surface of said substrate, introducing an impurity through said complex opening into said substrate to form an impurity-diffused region in said substrate, and selectively forming a conductive film on said impurity-diffused region and on said polycrystalline layer, to connect said impurity-diffused region and said polycrystalline film therewith.

Claim 11

Method for making the semiconductor device in accordance with claim 6, wherein said conductive film is formed with a material to be selectively deposited on semiconductor surface.

Claim 12

Method for making the semiconductor device in accordance with claim 6, wherein said conductive film is a tungsten film.

Claim 13

Method for making the semiconductor device in accordance with claim 6, wherein said conductive film is a tungsten film of low-pressure CVD deposition.

Claim 14

Method for making the semiconductor device in accordance with claim 8, which further comprises steps of after forming said polycrycrystalline semiconductor layer, forming a second insulation film on said polycrystalline semiconductor layer and further forming a second polycrystalline semiconductor layer on selected part of said second insulation film, and said forming of complex opening including boring through said second insulation film and said second polycrystalline semiconductor layer in one sequence together with said boring.

Claim 15

A semiconductor device in accordance with claim 12, wherein said first polycrystalline semiconductor layer and said second polycrystalline semiconductor layer are polycrystalline silicon layers.

Claim 16

A semiconductor device in accordance with claim 12, wherein said first polycrystalline semiconductor layer and said second polycrystalline semiconductor layer are polycrystalline silicon layers, and said conductive film is a tungsten film.