US5639678A
Expired / Lapsed
US
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Method of making semiconductor device with metal silicide nitride layer and metal silicide
Assignee: SK Hynix Inc
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Filing: 1995-01-10
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Granted: 1997-06-17
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Expires: 2015-01-10
Abstract
Abstract A MOSFET in accordance with this invention includes: a metal silicide layer formed on a impurity region and on the upper surface of a gate electrode; a metal silicide nitride layer formed on the metal silicide layer; and a metal nitride layer formed on the metal silicide nitride layer. The process for formation of a conductive layer includes the steps of: (a) forming an impurity region in a semiconductor substrate; (b) forming a metal layer on the impurity region; (c) carrying out a heat treatment under an inert gas atmosphere to form a metal silicide of metastable phase; and (d) carrying out a heat treatment under an nitrogen gas atmosphere so as for the metal silicide of the metastable phase to be phase-transited to a stable phase.
Inventors
- 👤 Chang-Jae Lee
- 👤 Chang-Reol Kim
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 12:51
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/60; H10D30/01; H10D30/021; H10D30/0223; H10D30/0227; H10D62/00; H10D62/80; H10D62/83; H10D64/00; H10D64/01; H10D64/011; H10D64/0111; H10D64/0112; H10D64/60; H10D64/62; H10D64/66; H10D64/661; H10D64/662; H10D64/663; H10P; H10P10/00; H10W; H10W20/00; H10W20/40
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
129 words
A process for formation of a conductive layer, comprising the steps of: (a) forming an impurity region on a silicon-containing semiconductor substrate; (b) forming a metal layer on the impurity region; (c) carrying out a first heat treatment under an inert gas atmosphere, wherein the metal and the silicon of the semiconductor substrate bond together to form a metal silicide of a metastable phase; and (d) carrying out a second heat treatment under a nitrogen containing atmosphere wherein the metal silicide of the metastable phase phase-transits to a metal silicide layer, a metal silicide nitride layer and a metal nitride layer of a stable phase; wherein a conductive layer is formed comprising the impurity region, the metal silicide layer, the metal silicide nitride layer, and the metal nitride layer.
Claim 2
Dependent Claim
129 words
A process for formation of a conductive layer, comprising the steps of: (a) forming an impurity region on a silicon-containing semiconductor substrate; (b) forming a metal layer on the impurity region; (c) carrying out a first heat treatment under an inert gas atmosphere, wherein the metal and the silicon of the semiconductor substrate bond together to form a metal silicide of a metastable phase; and (d) carrying out a second heat treatment under a nitrogen containing atmosphere wherein the metal silicide of the metastable phase phase-transits to a metal silicide layer, a metal silicide nitride layer and a metal nitride layer of a stable phase; wherein a conductive layer is formed comprising the impurity region, the metal silicide layer, the metal silicide nitride layer, and the metal nitride layer.
Claim 3
Dependent Claim
30 words
The process as claimed in claim 1, wherein: the metal silicide layer comprises TiSi 2 ; the metal silicide nitride layer comprises TiSiN; and the metal nitride layer comprises TiN.
Claim 4
Dependent Claim
59 words
The process as claimed in claim 1, wherein: the metal layer is formed by a sputtering process; the first heat treatment is carried out at a temperature of about 600°-700° C. under an argon or neon gas atmosphere; and the second heat treatment is carried out at a temperature of about 700° C. under an NH 3 gas atmosphere.
Claim 5
Dependent Claim
118 words
The process as claimed in claim 1, wherein: a titanium layer is formed on the impurity region; the first heat treatment is carried out at a temperature of about 600°-700° C. under an inert gas atmosphere so as to form a TiSi layer; and the second heat treatment is carried out at a temperature of about 700° C. under an NH 3 gas atmosphere so as to form a TiN layer on the surface of the TiSi layer, wherein the TiSi layer lying under the TiN layer forms a TiSi 2 layer; wherein a conductive layer is formed in which the semiconductor impurity region, the TiSi 2 layer and the TiN layer are stacked in the cited order.
Claim 6
Dependent Claim
91 words
The process as claimed in claim 4, wherein: the second heat treatment is carried out at a temperature of about 700° C. under an NH 3 gas atmosphere so as to form a TiN layer on the surface of the TiSi layer; and the TiSi layer lying under the TiN layer is formed partly into TiSiN and partly into TiSi 2 ; wherein a conductive layer is formed in which the semiconductor impurity region, the TiSi 2 layer, the TiSiN layer and the TiN layer are stacked in the cited order.
Claim 7
Dependent Claim
23 words
The process as claimed in claim 4, wherein the titanium layer is formed to a thickness of 1000 Angstroms by a sputtering process.
Claim 8
Dependent Claim
134 words
A process for making a MOSFET in a semiconductor substrate, comprising the steps of: (a) forming a source, a drain and a gate on a silicon containing substrate, wherein the source, drain and gate have exposed upper surfaces; (b) forming a metal layer on the whole surface; (c) carrying out a first heat treatment under an inert gas atmosphere wherein the metal layer and the silicon are bonded to form a metal silicide of a metastable phase; and (d) carrying out a second heat treatment under a nitrogen containing gas atmosphere wherein the metal silicide of the metastable phase phase-transits to a stable phase; wherein a conductive layer is formed on the source and drain, wherein the conductive layer comprises a metal silicide layer, a metal silicide nitride layer and a metal nitride layer.
Claim 9
Dependent Claim
134 words
A process for making a MOSFET in a semiconductor substrate, comprising the steps of: (a) forming a source, a drain and a gate on a silicon containing substrate, wherein the source, drain and gate have exposed upper surfaces; (b) forming a metal layer on the whole surface; (c) carrying out a first heat treatment under an inert gas atmosphere wherein the metal layer and the silicon are bonded to form a metal silicide of a metastable phase; and (d) carrying out a second heat treatment under a nitrogen containing gas atmosphere wherein the metal silicide of the metastable phase phase-transits to a stable phase; wherein a conductive layer is formed on the source and drain, wherein the conductive layer comprises a metal silicide layer, a metal silicide nitride layer and a metal nitride layer.
Claim 10
Dependent Claim
66 words
The process as claimed in claim 7, wherein: the metal layer is formed to a thickness of about 1000 Angstroms by a sputtering process; the first heat treatment is carried out at a temperature of about 600°-700° C. under an argon or neon gas atmosphere; and the second heat treatment is carried out at a temperature of about 700° C. under an NH 3 gas atmosphere.
Claim 11
Dependent Claim
91 words
The process as claimed in claim 7, wherein: a titanium layer is formed on the source, drain and gate; the first heat treatment is carried out at a temperature of about 600°-700° C. under an inert gas atmosphere so as to form a TiSi layer; and the second heat treatment is carried out at a temperature of about 700° C. under an NH 3 gas atmosphere so as to form a TiN layer on the TiSi layer, and the TiSi layer lying under the TiN layer forms a TiSi 2 layer.
Claim 12
Dependent Claim
93 words
The process as claimed in claim 9, wherein: the second heat treatment is carried out at a temperature of about 700° C. under an NH 3 gas atmosphere so as to form the TiN layer on the TiSi layer; and the TiSi layer lying under the TiN layer is formed partly into TiSiN and partly into TiSi 2 ; wherein the conductive layer is formed in which a semiconductor impurity region of the source or drain, the TiSi 2 layer, the TiSiN layer and the TiN layer are stacked in the cited order.
Claim 13
Dependent Claim
24 words
The process as claimed in claim 9, wherein, the titanium layer is formed in a thickness of about 1000 Angstroms by a sputtering process.
Claim 14
Dependent Claim
24 words
The process as claimed in claim 3, wherein, the metal layer is formed by a sputtering process to a thickness of about 1000 Angstroms.
Claim 15
Dependent Claim
18 words
The process as claimed in claim 3, wherein, the first heat treatment is conducted for about 20 minutes.
Claim 16
Dependent Claim
18 words
The process as claimed in claim 4, wherein, the first heat treatment is conducted for about 20 minutes.
Claim 17
Dependent Claim
18 words
The process as claimed in claim 8, wherein, the first heat treatment is conducted for about 20 minutes.
Claim 18
Dependent Claim
18 words
The process as claimed in claim 9, wherein, the first heat treatment is conducted for about 20 minutes.
Claim 19
Dependent Claim
119 words
A process for formation of a conductive layer, comprising the steps of: (a) forming an impurity region on a silicon-containing semiconductor substrate; (b) forming a metal layer on the impurity region; (c) carrying out a first heat treatment under an inert gas atmosphere, wherein the metal and the silicon of the semiconductor substrate bond together to form a metal silicide of a metastable phase; and (d) carrying out a second heat treatment under a nitrogen containing atmosphere wherein the metal silicide of the metastable phase phase-transits to a metal silicide layer and a metal nitride layer of a stable phase; wherein a conductive layer is formed comprising the impurity region, the metal silicide layer and the metal nitride layer.
Claim 20
Dependent Claim
119 words
A process for formation of a conductive layer, comprising the steps of: (a) forming an impurity region on a silicon-containing semiconductor substrate; (b) forming a metal layer on the impurity region; (c) carrying out a first heat treatment under an inert gas atmosphere, wherein the metal and the silicon of the semiconductor substrate bond together to form a metal silicide of a metastable phase; and (d) carrying out a second heat treatment under a nitrogen containing atmosphere wherein the metal silicide of the metastable phase phase-transits to a metal silicide layer and a metal nitride layer of a stable phase; wherein a conductive layer is formed comprising the impurity region, the metal silicide layer and the metal nitride layer.
Claim 21
Dependent Claim
23 words
The process as claimed in claim 17, wherein: the metal silicide layer comprises TiSi 2 ; and the metal nitride layer comprises TiN.
Claim 22
Dependent Claim
27 words
The process as claimed in claim 18, wherein a metal silicide nitride layer comprising TiSiN is formed between the metal silicide layer and the metal nitride layer.
Claim 23
Dependent Claim
59 words
The process as claimed in claim 17, wherein: the metal layer is formed by a sputtering process; the first heat treatment is carried out at a temperature of about 600°-700° C. under an argon or neon gas atmosphere; and the second heat treatment is carried out at a temperature of about 700° C. under an NH 3 gas atmosphere.
References Cited (Backward Citations)
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| 3.5 Years (Year 4) | 2000-06-16 | 2000-12-16 | 2001-06-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-06-16 | 2004-12-16 | 2005-06-17 | $3760.00 | Window Closed / Lapsed |
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