Patent US4770948A successfully refreshed from Google Patents.
US4770948A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High-purity metal and metal silicide target for LSI electrodes
Assignee: JAPAN ENERGY DENSHI ZAIRYO KK
•
Filing: 1986-06-23
•
Granted: 1988-09-13
•
Expires: 2006-06-23
Abstract
Abstract There is provided a high-purity molybdenum target or high-purity molybdenum silicide target for LSI electrodes which comprises a high-purity metallic molybdenum having an alkali metal content of not more than 100 ppb and a radioactive element content of not more than 10 ppb. Further, a process is provided for producing such target comprising a wet purification processing followed by a series of dry processings.
Inventors
- 👤 Hideo Oikawa
- 👤 Takao Amazawa
- 👤 Nakahachiro Honna
- 👤 Hideo Miyazaki
- 👤 Iwao Kyono
- 👤 Nobuyuki Mori
- 👤 Yoshiharu Katoh
- 👤 Masami Kuroki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 03:58
CPC Classifications
C; C22; C22B; C22B34/00; C22B34/30; C22B34/34; H; H10; H10D; H10D64/00; H10D64/01; H10D64/013; H10D64/01302; H10D64/01304; H10D64/01316; H10D64/01318; H10D64/0132; H10D64/60; H10D64/66; H10D64/665; H10D64/667; H10D64/668; H10P; H10P14/00; H10P14/40; H10P14/42; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12493; Y10T428/12528; Y10T428/12674; Y10T428/12771; Y10T428/12806; Y10T428/12826; Y10T428/12833
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
86 words
In a sputtering or vapor-deposition arrangement for the formation of LSI electrodes wherein a high-purity metal target is used as a source of metal vapor for said arrangement so that a film of said metal is formed on a substrate, the improvement comprises said metal of the target being selected from a group consisting of molybdenum, tungsten or compounds thereof, said metal having an alkali metal content of not more than about 100 ppb and a radioactive element content of not more than about 10 ppb.
Claim 2
Dependent Claim
86 words
In a sputtering or vapor-deposition arrangement for the formation of LSI electrodes wherein a high-purity metal target is used as a source of metal vapor for said arrangement so that a film of said metal is formed on a substrate, the improvement comprises said metal of the target being selected from a group consisting of molybdenum, tungsten or compounds thereof, said metal having an alkali metal content of not more than about 100 ppb and a radioactive element content of not more than about 10 ppb.
Claim 3
Dependent Claim
106 words
The arrangement of claim 1 wherein the high-purity metal target has been produced by dissolving the metal into an acid or ammonia to form an aqueous metal-containing solution; filtering the aqueous solution; causing the aqueous metal-containing solution to form metal-containing crystals by adjusting temperature and composition of the solution; collecting the crystals by solid-liquid separation; washing and drying the collected crystals; reducing the dried crystals by heating in the presence of high-purity hydrogen to produce a high-purity metal powder; compacting the powder; sintering the compact; electron beam melting the sintered compact to produce a high-purity metal ingot; and thereafter plastically working the ingot with subsequent machining.
Claim 4
Dependent Claim
24 words
The arrangement of claims 1 or 2 wherein the alkali metal is selected from a group consisting of sodium, potassium or the combination thereof.
Claim 5
Dependent Claim
24 words
The arrangement of claims 1 or 2 wherein the radioactive element is selected from a group consisting of uranium, thorium or a combination thereof.
Claim 6
Dependent Claim
39 words
The arrangement of claims 1 or 2 wherein the high-purity metal target has an iron content of about 0.5 ppm, a nickel content of less than about 0.05 ppm, and a cobalt content of less than about 0.01 ppm.
Claim 7
Dependent Claim
18 words
A metal electrode film deposited on a substrate made according to the arrangement of claims 1 or 2.
Claim 8
Dependent Claim
92 words
In a sputtering or vapor-deposition arrangement for the formation of LSI electrodes wherein a high-purity metal silicide target is used as a source of metal vapor for said arrangement so that a film of said metal is formed on a substrate, the improvement comprises said metal of said metal silicide of the target being selected from a group consisting of molybdenum, tungsten or compounds thereof, said metal silicide having an alkali metal content of not more than about 100 ppb and a radioactive element content of not more than about 10 ppb.
Claim 9
Dependent Claim
92 words
In a sputtering or vapor-deposition arrangement for the formation of LSI electrodes wherein a high-purity metal silicide target is used as a source of metal vapor for said arrangement so that a film of said metal is formed on a substrate, the improvement comprises said metal of said metal silicide of the target being selected from a group consisting of molybdenum, tungsten or compounds thereof, said metal silicide having an alkali metal content of not more than about 100 ppb and a radioactive element content of not more than about 10 ppb.
Claim 10
Dependent Claim
120 words
The arrangement of claim 7 wherein the high-purity metal silicide target has been produced by mixing a high-purity molybdenum or tungsten metal powder with a high-purity silicone powder; said molybdenum or tungsten metal powder being prepared by dissolving the metal into an acid or ammonia to form an aqueous metal-containing solution; filtering the aqueous solution; causing the aqueous metal-containing solution to form metal-containing crystals by adjusting temperature and composition of the solution; collecting the crystals by solid-liquid separation; washing and drying the collected crystals; reducing the dried crystals by heating in the presence of high-purity hydrogen to form a high-purity metal powder; compacting the mixture of powders; sintering the compact; and thereafter plastically working the sintered compact with subsequent machining.
Claim 11
Dependent Claim
24 words
The arrangement of claims 7 or 8 wherein the alkali metal is selected from a group consisting of sodium, potassium or a combination thereof.
Claim 12
Dependent Claim
24 words
The arrangement of claims 7 or 8 wherein the radioactive element is selected from a group consisting of uranium, thorium or a combination thereof.
Claim 13
Dependent Claim
40 words
The arrangement of claims 7 or 8 wherein said high-purity metal silicide target has an iron content of about 0.5 ppm, a nickel content of less than about 0.05 ppm, and a cobalt content of less than about 0.01 ppm.
Claim 14
Dependent Claim
19 words
The metal silicide electrode film deposited on a substrate made according to the arrangement of claims 7 or 8.
References Cited (Backward Citations)
US2948609A
Cited
CA670785A
Cited
JPS474130Y1
Cited
US3933474A
Cited
US4430296A
Cited
US4619695A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-09-13 | 1992-03-14 | 1992-09-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-09-13 | 1996-03-14 | 1996-09-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-09-13 | 2000-03-14 | 2000-09-13 | $7700.00 | Window Closed / Lapsed |