Patent US4619697A successfully refreshed from Google Patents.
US4619697A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sputtering target material and process for producing the same
Assignee: Mitsubishi Metal Corp
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Filing: 1985-08-27
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Granted: 1986-10-28
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Expires: 2005-08-27
Abstract
Abstract A novel target material for use in the sputter formation of a metal silicide film in electrode wiring in a semiconductor device, and a process for producing such target material are disclosed. The process for producing the target material is characterized by first impregnating molten silicon into a calcined body containing at least one silicide forming metal component and a silicon component and then forming a sintered body with a reduced oxygen content containing both a metal silicide and silicon. The target material prepared in accordance with the invention is extremely low not only in oxygen content but also in the concentrations of other impurities and has high deflective strength as compared with the conventional sintered target. The film formed by sputtering the target of the invention has appreciably reduced impurity levels and hence, very low electric resistivities. The target of the invention enables sputtering to be performed 5 times as fast as in the case using the conventional sintered target.
Inventors
- 👤 Kenichi Hijikata
- 👤 Tadashi Sugihara
- 👤 Masashi Komabayashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 17:02
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/515; C04B35/58; C04B35/58085; C04B35/58092; C04B35/622; C04B35/64; C04B35/645; C04B35/65; C22; C22B; C22B34/00; C22B34/30; C22B34/34; C23; C23C; C23C14/00; C23C14/22; C23C14/34; C23C14/3407; C23C14/3414
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
89 words
A process for producing a sputtering target material that is low in oxygen content and is used for forming a metal silicide film suitable for use in electrode wiring in a semiconductor device, said process comprising the steps of preparing a calcined body composed of at least one silicide-forming metal component and a silicon component, and impregnating molten silicon in said calcined body by means of contact with said molten silicon, thereby forming a sintered body with low oxygen content that is made of a metal silicide and silicon.
Claim 2
Dependent Claim
89 words
A process for producing a sputtering target material that is low in oxygen content and is used for forming a metal silicide film suitable for use in electrode wiring in a semiconductor device, said process comprising the steps of preparing a calcined body composed of at least one silicide-forming metal component and a silicon component, and impregnating molten silicon in said calcined body by means of contact with said molten silicon, thereby forming a sintered body with low oxygen content that is made of a metal silicide and silicon.
Claim 3
Dependent Claim
23 words
A process according to claim 1 wherein said calcined body contains a compound made of a silicide-forming metal component and a silicon component.
Claim 4
Dependent Claim
51 words
A process according to claim 1 wherein said calcined body is prepared from a mixture of the powders of a silicide-forming metal component and a silicon component that are blended in such proportions that the atomic ratio of silicon to the metal component is greater than 2 but not exceeding 4.
Claim 5
Dependent Claim
35 words
A process according to claim 1 wherein said silicide-forming metal component is at least one metal element selected from the group consisting of Mo, W, Ta, Ti, V, Cr, Zr, Nb, Hf, Re and Y.
Claim 6
Dependent Claim
29 words
A process according to claim 4 wherein said silicide-forming metal component is at least one high-melting metal element selected from the group consisting of Mo, W, Ta and Ti.
Claim 7
Dependent Claim
52 words
A process according to claim 2 wherein said compound made of a silicide-forming metal component and a silicon component is represented by the formula MSi 2 (wherein M is at least one metal element selected from the group consisting of Mo, W, Ta, Ti, V, Cr, Zr, Nb, Hf, Re and Y).
Claim 8
Dependent Claim
59 words
A process according to claim 2 wherein said compound made of a silicide-forming metal component and a silicon component is any compound other than those which are represented by the formula MSi 2 (wherein M is at least one metal element selected from the group consisting of Mo, W, Ta, Ti, V, Cr, Zr, Nb, Hf, Re and Y).
Claim 9
Dependent Claim
25 words
A process according to claim 7 wherein said compound made of a silicide-forming metal component and a silicon component is Mo 5 Si 3 .
Claim 10
Dependent Claim
42 words
A target material having a structure wherein the particles of a high-melting metal disilicide of the formula MSi 2 (wherein M=Mo, W, Ta or Ti) and/or a solid solution compound of said high-melting metal disilicide are dispersed in a continuous silicon matrix.
Claim 11
Dependent Claim
42 words
A target material having a structure wherein the particles of a high-melting metal disilicide of the formula MSi 2 (wherein M=Mo, W, Ta or Ti) and/or a solid solution compound of said high-melting metal disilicide are dispersed in a continuous silicon matrix.
Claim 12
Dependent Claim
23 words
A target material according to claim 9 wherein the continuous silicon matrix accounts for not smaller than 5 vol % of the target.
Claim 13
Dependent Claim
42 words
A target material according to claim 9 or 10 wherein the dispersed particles of the high-melting metal disilicide and/or the solid solution compound of said high-melting metal disilicide are present as discrete particles which are either circular or elliptical in cross section.
Claim 14
Dependent Claim
63 words
A target material according to claim 9 or 10 wherein the dispersed particles of the high-melting metal disilicide and/or the solid solution compound of said high-melting metal disilicide are present as a mixture of two particulate forms, one being a discrete particle which is either circular or elliptical in cross section and the other being an agglomerate of two or more discrete particles.
Claim 15
Dependent Claim
44 words
A target material according to claim 9 or 10 wherein the dispersed particles of the high-melting metal disilicide and/or the solid solution compound of said high-melting metal disilicide are present as agglomerates of discrete particles which are either circular or elliptical in cross section.
Claim 16
Dependent Claim
28 words
A target material according to claim 11 wherein the discrete particles which are either circular or elliptical in cross section have sizes ranging from 5 to 500 μm.
Claim 17
Dependent Claim
28 words
A target material according to claim 12 wherein the discrete particles which are either circular or elliptical in cross section have sizes ranging from 5 to 500 μm.
Claim 18
Dependent Claim
28 words
A target material according to claim 13 wherein the discrete particles which are either circular or elliptical in cross section have sizes ranging from 5 to 500 μm.
Claim 19
Dependent Claim
20 words
A target material according to claim 9 or 10 that has a porosity of not higher than 1 vol %.
Claim 20
Dependent Claim
18 words
A target material according to claim 11 that has a porosity of not higher than 1 vol %.
Claim 21
Dependent Claim
18 words
A target material according to claim 12 that has a porosity of not higher than 1 vol %.
Claim 22
Dependent Claim
18 words
A target material according to claim 13 that has a porosity of not higher than 1 vol %.
Claim 23
Dependent Claim
18 words
A target material according to claim 14 that has a porosity of not higher than 1 vol %.
Claim 24
Dependent Claim
18 words
A target material according to claim 15 that has a porosity of not higher than 1 vol %.
Claim 25
Dependent Claim
18 words
A target material according to claim 16 that has a porosity of not higher than 1 vol %.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-10-27 | 1990-04-28 | 1990-10-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-10-27 | 1994-04-28 | 1994-10-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-10-27 | 1998-04-28 | 1998-10-28 | $7700.00 | Window Closed / Lapsed |