Patent US2268156A successfully refreshed from Google Patents.
US4123293A
Expired / Lapsed
US
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Method of providing semiconductor pellet with heat sink
Assignee: Hitachi Ltd
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Filing: 1976-03-03
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Granted: 1978-10-31
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Expires: 1996-03-03
Abstract
Abstract A method of providing a silicon semiconductor pellet with a heat sink and a semiconductor device with such a heat sink. The heat sink to which the pellet is bonded with a eutectic alloy of gold and silicon interposed therebetween consists mainly of copper and contains a small amount of a metal other than copper and has been subjected to an annealing treatment.
Inventors
- 👤 Susumu Okikawa
- 👤 Osamu Yukawa
- 👤 Hiroshi Mikino
- 👤 Yoshio Nonaka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 12:15
CPC Classifications
B; B23; B23K; B23K35/00; B23K35/22; B23K35/24; B23K35/30; B23K35/3013; H; H10; H10W; H10W40/00; H10W40/20; H10W40/25; H10W40/255; H10W70/00; H10W70/01; H10W70/02; H10W72/00; H10W72/071; H10W72/073; H10W72/07331; H10W72/07336; H10W72/30; H10W72/351; H10W72/352; H10W72/851; H10W72/874; H10W72/884
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
93 words
A method of providing a silicon semiconductor pellet with a heat sink consisting mainly of copper, comprising the steps of incorporating about 0.10-0.13 weight % of a metal into said heat sink, said metal being Sn, Fe or Ag, annealing the heat sink into which said metal has been incorporated, and bonding a silicon pellet to the resulting heat sink by interposing a gold layer between said heat sink and said silicon pellet and by heating the resultant assembly to a temperature at which an eutectic alloy is formed of gold and silicon.
Claim 2
Independent Claim
93 words
A method of providing a silicon semiconductor pellet with a heat sink consisting mainly of copper, comprising the steps of incorporating about 0.10-0.13 weight % of a metal into said heat sink, said metal being Sn, Fe or Ag, annealing the heat sink into which said metal has been incorporated, and bonding a silicon pellet to the resulting heat sink by interposing a gold layer between said heat sink and said silicon pellet and by heating the resultant assembly to a temperature at which an eutectic alloy is formed of gold and silicon.
Claim 3
Dependent Claim
29 words
The method according to claim 1 in which said annealing is carried out by heating said heat sink at a temperature of about 390°-450° C. for about 3-10 minutes.
Claim 4
Dependent Claim
12 words
The method according to claim 2 in which said metal is Sn.
Claim 5
Independent Claim
90 words
A method of providing a silicon semiconductor pellet with a heat sink consisting mainly of copper, comprising the steps of incorporating about 0.10-0.13 weight % of a metal into said heat sink, said metal being Ni, annealing the heat sink into which said metal has been incorporated, and bonding a silicon pellet to the resulting heat sink by interposing a gold layer between said heat sink and said silicon pellet and by heating the resultant assembly to a temperature at which an eutectic alloy is formed of gold and silicon.
Claim 6
Independent Claim
90 words
A method of providing a silicon semiconductor pellet with a heat sink consisting mainly of copper, comprising the steps of incorporating about 0.10-0.13 weight % of a metal into said heat sink, said metal being Ni, annealing the heat sink into which said metal has been incorporated, and bonding a silicon pellet to the resulting heat sink by interposing a gold layer between said heat sink and said silicon pellet and by heating the resultant assembly to a temperature at which an eutectic alloy is formed of gold and silicon.
Claim 7
Dependent Claim
29 words
The method according to claim 4, in which said annealing is carried out by heating said heat sink at a temperature of about 390°-450° C. for about 3-10 minutes.
Claim 8
Independent Claim
107 words
A method of providing a silicon semiconductor pellet with a heat sink comprising the steps of: preparing a heat sink material consisting mainly of copper, said heat sink material containing about 0.10-0.13 weight % of a metal selected from the group consisting of Sn, Fe, Ag, Ni, Zn and P; rolling said heat sink material; shaping the rolled heat sink material into a heat sink having desired dimensions; annealing said heat sink; and placing said silicon semiconductor pellet over said heat sink with gold foil interposed therebetween and scrubbing them at a temperature for forming a eutectic alloy between said gold foil and said silicon semiconductor pellet.
Claim 9
Independent Claim
107 words
A method of providing a silicon semiconductor pellet with a heat sink comprising the steps of: preparing a heat sink material consisting mainly of copper, said heat sink material containing about 0.10-0.13 weight % of a metal selected from the group consisting of Sn, Fe, Ag, Ni, Zn and P; rolling said heat sink material; shaping the rolled heat sink material into a heat sink having desired dimensions; annealing said heat sink; and placing said silicon semiconductor pellet over said heat sink with gold foil interposed therebetween and scrubbing them at a temperature for forming a eutectic alloy between said gold foil and said silicon semiconductor pellet.
Claim 10
Dependent Claim
47 words
The method according to claim 6, in which said rolling is performed with a reduction of about 37-42%, said annealing is performed by a heat treatment at a temperature of about 390°-450° C. for about 3-10 minutes, and said eutectic alloy forming temperature is about 380°-450° C.
Claim 11
Dependent Claim
16 words
The method according to claim 6, in which said annealing is performed in a non-oxidizing atmosphere.
Claim 12
Dependent Claim
17 words
The method according to claim 8, in which said non-oxidizing atmosphere is a N 2 -gas atmosphere.
Claim 13
Independent Claim
104 words
A method of providing a silicon semiconductor pellet with a heat sink comprising the steps of: preparing a heat sink material consisting mainly of copper, said heat sink material containing about 0.10-0.13 weight % of a metal selected from the group consisting of Sn, Fe, and Ag; rolling said heat sink material; shaping the rolled heat sink material into a heat sink having desired dimensions; annealing said heat sink; and placing said silicon semiconductor pellet over said heat sink with gold foil interposed therebetween and scrubbing them at a temperature for forming a eutectic alloy between said gold foil and said silicon semiconductor pellet.
Claim 14
Independent Claim
104 words
A method of providing a silicon semiconductor pellet with a heat sink comprising the steps of: preparing a heat sink material consisting mainly of copper, said heat sink material containing about 0.10-0.13 weight % of a metal selected from the group consisting of Sn, Fe, and Ag; rolling said heat sink material; shaping the rolled heat sink material into a heat sink having desired dimensions; annealing said heat sink; and placing said silicon semiconductor pellet over said heat sink with gold foil interposed therebetween and scrubbing them at a temperature for forming a eutectic alloy between said gold foil and said silicon semiconductor pellet.
Claim 15
Dependent Claim
47 words
The method according to claim 10, in which said rolling is performed with a reduction of about 37-42%, said annealing is performed by a heat treatment at a temperature of about 390°-450° C. for about 3-10 minutes, and said eutectic alloy forming temperature is about 380°-450° C.
Claim 16
Dependent Claim
16 words
The method according to claim 10, in which said annealing is performed in a non-oxidizing atmosphere.
Claim 17
Dependent Claim
17 words
The method according to claim 12, in which said non-oxidizing atmosphere is a N 2 -gas atmosphere.
References Cited (Backward Citations)
US1969702A
Cited
US2599002A
Cited
US2971251A
Cited
US2897107A
Cited
US3047437A
Cited
US3097198A
Cited
US3143442A
Cited
US3342804A
Cited
US3398135A
Cited
US3335126A
Cited
US3359256A
Cited
US3445454A
Cited
US3522235A
Cited
US3592807A
Cited
US3406164A
Cited
GB1114603A
Cited
US3544550A
Cited
US3637651A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-10-30 | 1982-05-01 | 1982-10-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-10-30 | 1986-05-01 | 1986-10-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-10-30 | 1990-05-01 | 1990-10-31 | $7700.00 | Window Closed / Lapsed |