EP0042698A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Semiconductor device
Assignee: Toshiba Corp
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Filing: 1981-06-10
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Granted: —
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Expires: 2001-06-10
Abstract
Abstract A semiconductor device has a semiconductor substrate of a first conductivity type, and a diffused region of a second conductivity type. A first insulation film is formed on the substrate, having an opening exposing the surface of the diffused region. First and second polycrystalline layers doped with impurities associated with the second conductivity type are disposed in the opening, and the concentration of the impurities of the first polycrystalline layer is higher than that of the second polycrystalline layer. A metal electrode is formed on the second polycrystalline layer.
Inventors
- 👤 Sigeru Komatsu
- 👤 Hiroshi Inoue
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 04:52
CPC Classifications
H; H10; H10P; H10P32/00; H10P32/10; H10P32/17; H10P32/171; H10D; H10D64/00; H10D64/01; H10D64/011; H10D64/0111; H10D64/0113; H10P32/14; H10P32/1408; H10P32/1414
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
111 words
A semiconductor device comprising a semiconductor substrate of a first conductivity type; an insulation layer formed on said substrate and having at least one opening exposing a portion of said substrate; a polycrystalline semiconductor layer formed on said exposed substrate and containing impurity associated with a conductivity type opposite to that of the first conductivity type; a metal electrode formed on said polycrystalline layer; and a diffused region of the opposite conductivity type formed beneath the polycrystalline layer in said substrate; characterised in that the polycrystalline layer comprises two parts, one upon the other, the impurity concentration of the part adjacent the substrate being greater than that of the other part.
Claim 2
Dependent Claim
111 words
A semiconductor device comprising a semiconductor substrate of a first conductivity type; an insulation layer formed on said substrate and having at least one opening exposing a portion of said substrate; a polycrystalline semiconductor layer formed on said exposed substrate and containing impurity associated with a conductivity type opposite to that of the first conductivity type; a metal electrode formed on said polycrystalline layer; and a diffused region of the opposite conductivity type formed beneath the polycrystalline layer in said substrate; characterised in that the polycrystalline layer comprises two parts, one upon the other, the impurity concentration of the part adjacent the substrate being greater than that of the other part.
Claim 3
Dependent Claim
65 words
A semiconductor device as claimed in claim 1, characterised in that the concentration of impurities in said first polycrystalline layer is in the range of 0 . 6 x 10 21 to 2 x 10 21 /cm 3 , and the concentration of impurities in said second polycrystalline layer is in the range 1 x 10 20 to 5 x 10 20 /cm 3 .
Claim 4
Dependent Claim
29 words
A semiconductor device, characterised in that a further insulation layer is formed on said insulation layer, said insulation layer and said further insulation layer being etchable with different etchants.
Claim 5
Dependent Claim
29 words
A semiconductor device, characterised in that a further insulation layer is formed on said insulation layer, said insulation layer and said further insulation layer being etchable with different etchants.
Claim 6
Dependent Claim
29 words
A semiconductor device according to claim 3, characterised in that said insulation layer is made of a silicon oxide, and said further insulation layer is made of silicon nitride.
Claim 7
Independent Claim
132 words
A method of forming a semiconductor device comprising the steps of forming an insulation layer on a substate having a first conductivity type; exposing a selected portion of the substrate through the insulation layer; depositing a polycrystalline semiconductor layer having impurities associated with a second conductivity type opposite the first conductivity type on the exposed substrate; diffusing material from the polycrystalline layer into the substrate to form a diffused region of the second conductivity type ; forming a metal electrode on the polycrystalline layer; characterised in that the polycrystalline layer is in two parts deposited separately, the first part being deposited on to the substrate and the second part being deposited on to the first part and the impurity concentration of the first part being greater than that of the second part.
Claim 8
Independent Claim
132 words
A method of forming a semiconductor device comprising the steps of forming an insulation layer on a substate having a first conductivity type; exposing a selected portion of the substrate through the insulation layer; depositing a polycrystalline semiconductor layer having impurities associated with a second conductivity type opposite the first conductivity type on the exposed substrate; diffusing material from the polycrystalline layer into the substrate to form a diffused region of the second conductivity type ; forming a metal electrode on the polycrystalline layer; characterised in that the polycrystalline layer is in two parts deposited separately, the first part being deposited on to the substrate and the second part being deposited on to the first part and the impurity concentration of the first part being greater than that of the second part.
Claim 9
Dependent Claim
31 words
A method as claimed in claim 5, characterised in that the concentration ratio of the impurities in said first and econd polycrystalline layers are in the range of 1.5 to 100.
Claim 10
Dependent Claim
59 words
A method as claimed in claim 5, characterised in that the concentration of impurities in the first polycrystalline layer is in the range of 0.6 x 10 21 to 2 x 10 21 /cm 3 , and the concentration of impurities in the second polycrystalline layer is in the range of 1 x 10 20 to 5 x 1020/cm3.
Claim 11
Dependent Claim
34 words
A method as claimed in claim 5, further comprising the step of forming a further insulation layer on the insulation layer, the further insulation layer and the insulation layer being etchable with different etchants.
References Cited (Backward Citations)
No citation records indexed.
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