Patent CA704304A successfully refreshed from Google Patents.
Patent US4976393A successfully refreshed from Google Patents.
US4976393A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Semiconductor device and production process thereof, as well as wire bonding device used therefor
Assignee: Hitachi Ltd
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Filing: 1987-12-17
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Granted: 1990-12-11
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Expires: 2007-12-17
Abstract
Abstract The present invention concerns a semiconductor device and a process for producing semiconductor device, as well as a wire bonding device used therefor. In accordance with the present invention, a ball formed at the top end of a bonding wire is sphericalized by electric discharge within a reducing gas atmosphere at a high temperature from 100° C. to 200° C. By using the ball of the bonding wire formed under such a condition to the bonding of the bonding pad of a semiconductor pellet, it is possible to conduct highly reliable ball bonding with excellent bondability and with no development of cracks or the like in the semiconductor pellet, as well as to obtain a highly reliable semiconductor device, that is, LSI or IC.
Inventors
- 👤 Makoto Nakajima
- 👤 Yoshio Ohashi
- 👤 Toshio Chuma
- 👤 Kazuo Hatori
- 👤 Isao Araki
- 👤 Masahiro Koizumi
- 👤 Jin Onuki
- 👤 Hitoshi Suzuki
- 👤 Susumu Okikawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 15:16
CPC Classifications
B; B23; B23K; B23K20/00; B23K20/002; B23K20/004; B23K20/005; B23K20/007; H; H10; H10W; H10W72/00; H10W72/071; H10W72/0711; H10W72/01; H10W72/015; H10W72/01551; H10W72/07141; H10W72/07168; H10W72/07178; H10W72/073; H10W72/075; H10W72/07502; H10W72/07511; H10W72/07521; H10W72/07531; H10W72/07532; H10W72/07533; H10W72/07541; H10W72/50; H10W72/531; H10W72/536; H10W72/5363; H10W72/551; H10W72/552; H10W72/5522; H10W72/5524; H10W72/5525; H10W72/59; H10W72/851; H10W72/874; H10W72/884; H10W72/90; H10W72/951; H10W72/952; H10W74/00; H10W90/00; H10W90/701; H10W90/731; H10W90/736; H10W90/751; H10W90/756
Claims Analysis
Total Claims: 34
Claim 1
Independent Claim
238 words
A fabrication method for a semiconductor device having a semiconductor pellet, at least one bonding pad, having a major surface, disposed on one major surface of the pellet, and at least one lead member disposed outside the pellet, comprising: (a) forming a ball on an end of a bonding wire, projecting from the tip of a bonding capillary, by electric discharge between the end of the wire and an electrode, in a reducing gas atmosphere including at least hydrogen, the hydrogen being contained in the gas atmosphere in an amount smaller than 4% by volume, the gas atmosphere having a temperature of at least 100° C., but lower than a temperature at which the wire sticks to the bonding capillary, the gas atmoshpere, at the gas atmosphere temperature, being supplied through nozzles directed at the end of wire, the gas atmosphere being maintained at said temperature at least while the ball is being hardened, so as to provide a softened ball as compared to the hardness of a ball formed in a gas atmosphere at lower temperatures, the wire being made of copper; and (b) ball-bonding the wire to the pad through the ball with the capillary, by pushing the ball against the major surface of the pad vertically while the ball is projected from the tip of the capillary, whereby, due to said softened ball, cracking during ball-bonding is avoided while a predetermined bonding area is achieved.
Claim 2
Dependent Claim
238 words
A fabrication method for a semiconductor device having a semiconductor pellet, at least one bonding pad, having a major surface, disposed on one major surface of the pellet, and at least one lead member disposed outside the pellet, comprising: (a) forming a ball on an end of a bonding wire, projecting from the tip of a bonding capillary, by electric discharge between the end of the wire and an electrode, in a reducing gas atmosphere including at least hydrogen, the hydrogen being contained in the gas atmosphere in an amount smaller than 4% by volume, the gas atmosphere having a temperature of at least 100° C., but lower than a temperature at which the wire sticks to the bonding capillary, the gas atmoshpere, at the gas atmosphere temperature, being supplied through nozzles directed at the end of wire, the gas atmosphere being maintained at said temperature at least while the ball is being hardened, so as to provide a softened ball as compared to the hardness of a ball formed in a gas atmosphere at lower temperatures, the wire being made of copper; and (b) ball-bonding the wire to the pad through the ball with the capillary, by pushing the ball against the major surface of the pad vertically while the ball is projected from the tip of the capillary, whereby, due to said softened ball, cracking during ball-bonding is avoided while a predetermined bonding area is achieved.
Claim 3
Dependent Claim
54 words
A fabrication method according to claim 1, further comprising: (c) after the step (b), transferring the capillary to a position above one end portion of the lead; and then (d) wedge-bonding the wire to the one end portion of the lead with the capillary by pushing the wire against the surface of the lead.
Claim 4
Dependent Claim
15 words
A fabrication method according to claim 2, wherein the bonding pad is made of aluminum.
Claim 5
Dependent Claim
26 words
A fabrication method according to claim 3, wherein the electric discharge is performed with the bonding wire as an anode and the electrode as a cathode.
Claim 6
Dependent Claim
35 words
A fabrication method according to claim 4, wherein the electric discharge is generated between the end of the wire and the electrode, the end of the wire and the electrode being separated a predetermined distance.
Claim 7
Dependent Claim
23 words
A fabrication method according to claim 5, wherein the bonding wire is bonded to the pad by heating in combination with ultrasonic vibration.
Claim 8
Dependent Claim
22 words
A fabrication method according to claim 6, wherein the wire is bonded to the lead by heating in combination with ultrasonic vibration.
Claim 9
Dependent Claim
17 words
A fabrication method according to claim 8, wherein the gas atmosphere temperature is higher than 150° C.
Claim 10
Dependent Claim
20 words
A fabrication method according to claim 8, wherein the gas at atmosphere is not greater than 200° C. in temperature.
Claim 11
Dependent Claim
23 words
A fabrication method according to claim 9, wherein the gas atmosphere comprises, in addition to hydrogen, at least one of nitrogen and argon.
Claim 12
Dependent Claim
22 words
A fabrication method according to claim 10, wherein the gas atmosphere consists of hydrogen and at least one of nitrogen and argon.
Claim 13
Dependent Claim
23 words
A fabrication method according to claim 10, wherein the hydrogen is in the gas atmosphere in an amount smaller than 3% by volume.
Claim 14
Dependent Claim
19 words
A fabrication method according to claim 5, wherein the gas atmosphere is not greater than 200° C. in temperature.
Claim 15
Dependent Claim
23 words
A fabrication method according to claim 13, wherein the gas atmosphere comprises, in addition to hydrogen, at least one of nitrogen and argon.
Claim 16
Dependent Claim
22 words
A fabrication method according to claim 14, wherein the gas atmosphere consists of hydrogen and at least one of nitrogen and argon.
Claim 17
Dependent Claim
23 words
A fabrication method according to claim 14, wherein the hydrogen is in the gas atmosphere in an amount smaller than 3% by volume.
Claim 18
Dependent Claim
22 words
A fabrication method according to claim 5, wherein the wire is bonded to the lead by heating in combination with ultrasonic vibration.
Claim 19
Dependent Claim
17 words
A fabrication method according to claim 17, wherein the gas atmosphere temperature is at least 150° C.
Claim 20
Dependent Claim
26 words
A fabrication method according to claim 2, wherein the electric discharge is performed using the bonding wire as an anode and the electrode as a cathode.
Claim 21
Dependent Claim
35 words
A fabrication method according to claim 19, wherein the electric discharge is generated between the end of the wire and the electrode, the end of the wire and the electrode being separated a predetermined distance.
Claim 22
Dependent Claim
23 words
A fabrication method according to claim 20, wherein the bonding wire is bonded to the pad by heating in combination with ultrasonic vibration.
Claim 23
Dependent Claim
22 words
A fabrication method according to claim 21, wherein the wire is bonded to the lead by heating in combination with ultrasonic vibration.
Claim 24
Dependent Claim
15 words
A fabrication method according to claim 22, wherein the bonding pad is made of aluminum.
Claim 25
Dependent Claim
17 words
A fabrication method according to claim 23, wherein the gas atmosphere temperature is at least 150° C.
Claim 26
Dependent Claim
18 words
A fabrication method according to claim 24, wherein the gas atmosphere temperature is not greater than 200° C.
Claim 27
Dependent Claim
23 words
A fabrication method according to claim 25, wherein the gas atmosphere includes, in addition to hydrogen, at least one of nitrogen and argon.
Claim 28
Dependent Claim
24 words
A fabrication method according to claim 26, wherein the hydrogen is contained in the gas atmosphere in an amount smaller then 3% by volume.
Claim 29
Dependent Claim
26 words
A fabrication method according to claim 2, wherein the wire is wedge-bonded to the one end portion of the lead in a lead oxidation-preventing gas atmosphere.
Claim 30
Dependent Claim
15 words
A fabrication method according to claim 28, wherein the lead oxidation-preventing gas atmosphere contains hydrogen.
Claim 31
Dependent Claim
26 words
A fabrication method according to claim 29, wherein the hydrogen is contained in the lead oxidation-preventing gas atmosphere in an amount less than 4% by volume.
Claim 32
Dependent Claim
18 words
A fabrication method according to claim 1, wherein the gas atmosphere has a temperature of 100° C.-200° C.
Claim 33
Dependent Claim
18 words
A fabrication method according to claim 31, wherein the gas atmosphere has a temperature of 150° C.-200° C.
Claim 34
Dependent Claim
20 words
A fabrication method according to claim 32, wherein the gas atmosphere is also supplied through nozzles directed at the electrode.
References Cited (Backward Citations)
JPS58143540A
Cited
EP0088557A2
Cited
GB2137914A
Cited
JPS607137A
Cited
GB2146937A
Cited
GB2157607A
Cited
US4732313A
Cited
US4705204A
Cited
JPS61290732A
Cited
JPS62219935A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-12-10 | 1994-06-11 | 1994-12-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-12-10 | 1998-06-11 | 1998-12-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-12-10 | 2002-06-11 | 2002-12-11 | $7700.00 | Window Closed / Lapsed |