Patent EP0617474A1 successfully refreshed from Google Patents.
EP0110307A2
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Semiconductor die-attach technique and composition therefor
Assignee: Samsung Electronics Co Ltd
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Filing: 1983-11-23
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Granted: —
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Expires: 2003-11-23
Abstract
Abstract A method of attaching semiconductor die to a package substrate and a composition for such die attach is disclosed, which method and composition comprise the combination of a low and a high-melting powder with a vehicle consisting of a solvent and a binder so as to form a thick-film ink. The ink is deposited onto the package substrate and the semiconductor die with a metallized back surface is located in contact with the deposited ink. The package containing the ink and the die is heated to a temperature of approximately 160 °C so as to remove the solvent from the powders and the residual binder. Next, the package is fired at a temperature within the range of approximately 200 °C to 430 °C so as to melt the low-melting powder which bonds the chip to the package substrate. Then, a lid is sealed over the die-receiving cavity of the package by heating the package and the bonded die to a temperature within a range of approximately 400°C to 450°C wherein the low-melting powder remelts and the high-melting powder partially dissolves into the liquid of the remelted low-melting powder.
Inventors
- 👤 Carl Edward Hoge
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 02:04
CPC Classifications
H; H10; H10W; H10W72/00; H10W72/30; B; B23; B23K; B23K35/00; B23K35/02; B23K35/0222; B23K35/0244; B23K35/025; H10W20/00; H10W20/40; H10W72/071; H10W72/073; H10W72/07331; H10W72/07337; H10W72/321; H10W72/325; H10W72/351; H10W72/352; H10W72/353; H10W72/354
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
149 words
A method of attaching semiconductor die to a package substrate comprising: a. combining a low and a high melting powder with a vehicle consisting of a solvent and a binder so as to form an ink; b. depositing said ink onto the package substrate; c. locating the semiconductor die in contact with the deposited ink; d. heating the package containing the ink and the die to a temperature within a range of approximately 150°C to 160°C so as to remove the solvent from said powders; e. firing the package containing the dried ink and die to a temperature within a range of approximately 350°C to 430°C so as to melt the low-melting powder; and, f. heating the package and the bonded die to a temperature up to approximately 450°C wherein said low-melting phase may remelt and said high-melting powder partially dissolves into the liquid of said remelted low-melting powder.
Claim 2
Independent Claim
149 words
A method of attaching semiconductor die to a package substrate comprising: a. combining a low and a high melting powder with a vehicle consisting of a solvent and a binder so as to form an ink; b. depositing said ink onto the package substrate; c. locating the semiconductor die in contact with the deposited ink; d. heating the package containing the ink and the die to a temperature within a range of approximately 150°C to 160°C so as to remove the solvent from said powders; e. firing the package containing the dried ink and die to a temperature within a range of approximately 350°C to 430°C so as to melt the low-melting powder; and, f. heating the package and the bonded die to a temperature up to approximately 450°C wherein said low-melting phase may remelt and said high-melting powder partially dissolves into the liquid of said remelted low-melting powder.
Claim 3
Dependent Claim
28 words
A method as in Claim 1 further characterized by said low-melting powder being formed of compositions selected from the group consisting of lead, indium, silver, gold and tin.
Claim 4
Dependent Claim
30 words
A method as in Claim 2 further characterized by said low-melting powder being formed of approximately 80 to 90 weight percent lead and approximately 20 to 10 weight percent indium.
Claim 5
Dependent Claim
31 words
A method as in Claim 2 further characterized by said low-melting powder being formed of approximately 92.5 weight percent lead, approximately 5 weight percent indium and approximately 2.5 weight percent silver.
Claim 6
Dependent Claim
18 words
A method as in Claim 3 or 4 further characterized by said high-melting powder being formed of silver.
Claim 7
Dependent Claim
26 words
A method as in Claim 2 further characterized by said low-melting powder being formed of approximately 80 weight percent gold and approximately 20 weight percent tin.
Claim 8
Dependent Claim
16 words
A method as in Claim 6 further characterized by said high-melting powder being formed of gold.
Claim 9
Dependent Claim
41 words
A method as in Claim 1 further characterized by said low and high-melting powders being combined at a ratio of approximately 40 to 70 volume percent of the low-melting powder and approximately 60 to 30 volume percent of the high-melting powder.
Claim 10
Dependent Claim
29 words
A method as in Claim 1 further characterized by the particle sizes of each of the low and high-melting powders being no larger than approximately 0.002 inches (50 microns).
Claim 11
Dependent Claim
21 words
A method as in Claim 1 further characterized by said solvent being selected from the group consisting of terpineol and butylcarbitol-acetate.
Claim 12
Dependent Claim
32 words
A method as in Claim 1 further characterized by said vehicle being formed of approximately 97 to 99 weight percent terpineol solvent and approximately 3 to 1 weight percent ethyl cellulose binder.
Claim 13
Dependent Claim
18 words
A method as in Claim 1 further characterized by said firing step being performed in a hydrogen atmosphere.
Claim 14
Dependent Claim
24 words
A method as in Claim 1 further characterized by said binder being selected from the group consisting of ethyl cellulose, nitrocellulose and acrylic resin.
Claim 15
Dependent Claim
66 words
A semiconductor die-attach composition comprising: a. a low-melting metal powder having a melting point within the range of approximately 173°C to 350°C; b. a high-melting metal powder having a melting point within the range of approximately 900°C to 1100°C and being soluble in said low-melting powder; and c. a vehicle for blending said low-melting powder with said high-melting powder so as to form a thick-film ink.
Claim 16
Dependent Claim
66 words
A semiconductor die-attach composition comprising: a. a low-melting metal powder having a melting point within the range of approximately 173°C to 350°C; b. a high-melting metal powder having a melting point within the range of approximately 900°C to 1100°C and being soluble in said low-melting powder; and c. a vehicle for blending said low-melting powder with said high-melting powder so as to form a thick-film ink.
Claim 17
Dependent Claim
25 words
A composition as in Claim 14 further characterized by said low-melting powder being selected from the group consisting of lead, indium, silver, gold and tin.
Claim 18
Dependent Claim
30 words
A composition as in Claim 15 further characterized by said low-melting powder being formed of approximately 80 to 90 weight percent lead and approximately 20 to 10 weight percent indium.
Claim 19
Dependent Claim
31 words
A composition as in Claim 15 further characterized by said low-melting powder being formed of approximately 92.5 weight percent lead, approximately 5 weight percent indium and approximately 2.5 weight percent silver.
Claim 20
Dependent Claim
18 words
A composition as in Claim 16 or 17 further characterized by said high-melting powder being formed of silver.
Claim 21
Dependent Claim
25 words
A composition as in Claim 15 further characterized by said low-melting powder being formed of approximately 80 weight percent gold and 20 weight percent tin.
Claim 22
Dependent Claim
16 words
A composition as in Claim 19 further characterized by said high-melting powder being formed of gold.
Claim 23
Dependent Claim
41 words
A composition as in Claim 14 further characterized by said low and high-melting powders being combined at a ratio of approximately 40 to 70 volume percent of said low-melting powder and approximately 60 to 30 volume percent of said high-melting powder.
Claim 24
Dependent Claim
33 words
A composition as in Claim 14 further characterized by said organic vehicle being formed of approximately 98 to 99 weight percent terpineol solvent and approximately 2 to 1 weight percent ethyl cellulose binder.
References Cited (Backward Citations)
No citation records indexed.
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