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US4476157A Expired / Lapsed US ⏱️ 0.0 years remaining

Method for manufacturing schottky barrier diode

Assignee: Toshiba Corp
•
Filing: 1982-07-28
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Granted: 1984-10-09
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Expires: 2002-07-28
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Abstract

Abstract Disclosed is a method for manufacturing a Schottky barrier diode. An insulating film is formed on a silicon substrate of one conductivity type. The insulating film has a hole therein partially exposing the surface of the silicon substrate. Then, a polycrystalline silicon layer is formed to cover that portion of the insulating film which surrounds the contact hole, the inner wall of the contact hole, and the exposed surface portion of the silicon substrate. Thereafter, a metal layer is deposited to cover at least the polycrystalline silicon layer. The polycrystalline silicon is then alloyed with the metal to form a metal silicide layer.

Inventors

  • 👤 Satoshi Shinozaki

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 15:26
CPC Classifications
H; H10; H10D; H10D64/00; H10D64/01; H10D64/012; H10D64/0121

Claims Analysis

Total Claims: 17
Claim 1
Independent Claim 117 words
A method for manufacturing a Schottky barrier diode, comprising the steps of: forming an insulating film on a silicon substrate of one conductivity type, said insulating film having a hole partially exposing the surface of said silicon substrate; forming a layer of polycrystalline silicon containing an impurity of said one conductivity type to cover a portion of said insulating film surrounding said hole, an inner wall of said hole and the exposed surface portion of said silicon substrate; depositing a layer of a Schottky barrier formation metal to cover at least said polycrystalline silicon layer; and alloying said polycrystalline silicon with said Schottky barrier formation metal to form a metal silicide layer which rectification-contacts said silicon substrate.
Claim 2
Independent Claim 117 words
A method for manufacturing a Schottky barrier diode, comprising the steps of: forming an insulating film on a silicon substrate of one conductivity type, said insulating film having a hole partially exposing the surface of said silicon substrate; forming a layer of polycrystalline silicon containing an impurity of said one conductivity type to cover a portion of said insulating film surrounding said hole, an inner wall of said hole and the exposed surface portion of said silicon substrate; depositing a layer of a Schottky barrier formation metal to cover at least said polycrystalline silicon layer; and alloying said polycrystalline silicon with said Schottky barrier formation metal to form a metal silicide layer which rectification-contacts said silicon substrate.
Claim 3
Dependent Claim 21 words
A method according to claim 1, further including the step of forming a wiring metal layer on said metal silicide layer.
Claim 4
Dependent Claim 22 words
A method according to claim 2, wherein said Schottky barrier formation metal is alloyed also with a surface silicon of said substrate.
Claim 5
Dependent Claim 18 words
A method according to claim 3, wherein the alloying is performed by heating in an inert gas atmosphere.
Claim 6
Dependent Claim 29 words
A method according to claim 1, wherein said insulating film comprises a silicon dioxide film on said silicon substrate and a silicon nitride film on said silicon dioxide film.
Claim 7
Dependent Claim 26 words
A method according to claim 2, further including the step of forming a second insulating film to cover an edge portion of said metal silicide layer.
Claim 8
Dependent Claim 29 words
A method according to claim 2, further including the step of forming a second metal layer for preventing a reaction of said metal silicide with said wiring metal layer.
Claim 9
Dependent Claim 44 words
A method according to claim 7, wherein said metal silicide layer comprises platinum silicide, said wiring metal layer comprises aluminum or an alloy thereof, and said second metal layer comprises a member selected from the group consisting of titanium, tungsten, and a titanium-tungsten alloy.
Claim 10
Independent Claim 20 words
A method according to one of claims 1 through 8, wherein said impurity is ion-implanted into said polycrystalline silicon layer.
Claim 11
Independent Claim 44 words
A method according to one of claims 1 through 8, further comprising the step of forming, prior to the alloy formation, a diffusion layer in the surface of said silicon substrate by diffusing the impurity from said polycrystalline silicon layer into said silicon substrate.
Claim 12
Dependent Claim 24 words
A method according to claim 10, wherein an interface between said metal silicide layer and said silicon substrate is located within said diffusion layer.
Claim 13
Dependent Claim 20 words
A method according to claim 11, wherein said one conductivity type is an n-conductivity type, and said impurity is arsenic.
Claim 14
Independent Claim 140 words
A method for manufacturing a Schottky barrier diode, comprising the steps of: forming an insulating film on a silicon substrate of one conductivity type, said insulating film having a hole partially exposing the surface of said silicon substrate and said insulating film having a layered structure comprising a first layer and a second layer formed on and overhanging said first layer; forming a layer of polycrystalline silicon containing an impurity of said one conductivity type to cover a portion of said insulating film surrounding said hole, an inner wall of said hole and the exposed surface portion of said silicon substrate; depositing a layer of a Schottky barrier formation metal to cover at least said polycrystalline silicon layer; and alloying said polycrystalline silicon with said Schottky barrier formation metal to form a metal silicide layer which rectification-contacts said silicon substrate.
Claim 15
Independent Claim 140 words
A method for manufacturing a Schottky barrier diode, comprising the steps of: forming an insulating film on a silicon substrate of one conductivity type, said insulating film having a hole partially exposing the surface of said silicon substrate and said insulating film having a layered structure comprising a first layer and a second layer formed on and overhanging said first layer; forming a layer of polycrystalline silicon containing an impurity of said one conductivity type to cover a portion of said insulating film surrounding said hole, an inner wall of said hole and the exposed surface portion of said silicon substrate; depositing a layer of a Schottky barrier formation metal to cover at least said polycrystalline silicon layer; and alloying said polycrystalline silicon with said Schottky barrier formation metal to form a metal silicide layer which rectification-contacts said silicon substrate.
Claim 16
Dependent Claim 17 words
A method as in claim 13, wherein said first layer of said insulating film comprises silicon dioxide.
Claim 17
Dependent Claim 17 words
A method as in claim 13, wherein said second layer of said insulating film comprises silicon nitride.

References Cited (Backward Citations)

US4128670A Cited
US4364166A Cited
US4313971A Cited
US4375999A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-10-09 1988-04-09 1988-10-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-10-09 1992-04-09 1992-10-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-10-09 1996-04-09 1996-10-09 $7700.00 Window Closed / Lapsed

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