Patent US6048656A successfully refreshed from Google Patents.
US6048656A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Void-free underfill of surface mounted chips
Assignee: Micron Technology Inc
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Filing: 1999-05-11
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Granted: 2000-04-11
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Expires: 2019-05-11
Abstract
Abstract A vacuum source creates uniform flow of underfill material in the interstices between a semiconductor device and a substrate. A semiconductor device is attached to a substrate and a plurality of dams surround the semiconductor device. The dams have at least a first opening to allow underfill material to be injected into the space between the semiconductor device and the substrate. A vacuum cup is placed over a second opening and a vacuum source is applied to draw the underfill material throughout the interstices. Because the vacuum source is drawing the underfill material in a uniform manner, the underfill material fills the space without creating voids. If desired, multiple vacuum sources and multiple injection sites may be used. The underfill material may also be inserted from an aperture in the substrate located beneath the semiconductor device.
Inventors
- 👤 Salman Akram
- 👤 Tongbi Jiang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 15:10
CPC Classifications
H; H10; H10W; H10W72/00; H10W72/01; H10W72/011; H10W72/0113; H10W72/30; H10W74/00; H10W74/01; H10W74/012; H10W74/10; H10W74/15; H10W70/00; H10W70/60; H10W70/67; H10W70/68; H10W70/681; H10W72/013; H10W72/01308; H10W72/071; H10W72/072; H10W72/073; H10W72/07311; H10W72/381; H10W72/387; H10W72/851; H10W72/853; H10W72/856; H10W90/00; H10W90/701; H10W90/721; H10W90/724; H10W90/731; H10W90/734
Claims Analysis
Total Claims: 57
Claim 1
Independent Claim
84 words
A method of attaching a semiconductor device to a substrate, the method comprising: electrically and mechanically connecting the semiconductor device to the substrate, leaving a gap therebetween; providing a dam on the substrate substantially surrounding the semiconductor device, the dam having at least a first opening and a second opening; inserting an underfill material into the gap from the first opening of the dam; and applying a continuous vacuum to the second opening of the dam to draw the underfill material into the gap.
Claim 2
Independent Claim
84 words
A method of attaching a semiconductor device to a substrate, the method comprising: electrically and mechanically connecting the semiconductor device to the substrate, leaving a gap therebetween; providing a dam on the substrate substantially surrounding the semiconductor device, the dam having at least a first opening and a second opening; inserting an underfill material into the gap from the first opening of the dam; and applying a continuous vacuum to the second opening of the dam to draw the underfill material into the gap.
Claim 3
Dependent Claim
15 words
The method of claim 1, wherein the vacuum draws the underfill material into the gap.
Claim 4
Dependent Claim
29 words
The method of claim 1, wherein the first opening is at a first corner of the dam and the second opening is at a second corner of the dam.
Claim 5
Dependent Claim
14 words
The method of claim 1, wherein the underfill is inserted with a dispensing needle.
Claim 6
Dependent Claim
15 words
The method of claim 1, wherein a vacuum cup forms a seal with the dam.
Claim 7
Dependent Claim
19 words
The method of claim 1, wherein the underfill is inserted through a first plurality of openings of the dam.
Claim 8
Dependent Claim
15 words
The method of claim 6, wherein each opening is in a corner of the dam.
Claim 9
Dependent Claim
19 words
The method of claim 1, wherein the vacuum is applied to a second plurality of openings in the dam.
Claim 10
Dependent Claim
15 words
The method of claim 8, wherein each opening is in a corner of the dam.
Claim 11
Dependent Claim
18 words
The method of claim 1, wherein providing the dam comprises dispensing a glob top fence onto the substrate.
Claim 12
Dependent Claim
20 words
The method of claim 1, wherein providing the dam comprises forming the dam at least as high as the gap.
Claim 13
Dependent Claim
79 words
A process for underfilling a device on a substrate comprising: positioning the device on a substrate such that a space is created between the device and the substrate, the device having a plurality of sides; substantially enclosing the plurality of sides of the device with a dam; inserting an underfill material into at least a first opening in the dam; and drawing the underfill material into the space toward a second opening in the dam with a continuous vacuum.
Claim 14
Dependent Claim
79 words
A process for underfilling a device on a substrate comprising: positioning the device on a substrate such that a space is created between the device and the substrate, the device having a plurality of sides; substantially enclosing the plurality of sides of the device with a dam; inserting an underfill material into at least a first opening in the dam; and drawing the underfill material into the space toward a second opening in the dam with a continuous vacuum.
Claim 15
Dependent Claim
21 words
The process of claim 12, wherein the dam creates a substantial seal against the plurality of sides of the semiconductor device.
Claim 16
Dependent Claim
17 words
The process of claim 12, wherein the semiconductor device and the dam have a generally rectangular shape.
Claim 17
Dependent Claim
18 words
The process of claim 14, wherein the first opening is located at a first corner of the dam.
Claim 18
Dependent Claim
16 words
The process of claim 15, wherein the second opening is located cater-cornered from the first opening.
Claim 19
Dependent Claim
14 words
The process of claim 12, wherein the underfill material is drawn using a vacuum.
Claim 20
Dependent Claim
14 words
The process of claim 17, wherein the vacuum is applied by a vacuum cup.
Claim 21
Dependent Claim
15 words
The process of claim 18, wherein the vacuum cup creates a seal with the dam.
Claim 22
Dependent Claim
19 words
The process of claim 17, wherein the vacuum is applied to a second plurality of openings in the dam.
Claim 23
Dependent Claim
20 words
The process of claim 12, wherein the underfill material is inserted into a first plurality of openings in the dam.
Claim 24
Dependent Claim
18 words
The process of claim 12, wherein the second opening is at a lower pressure than the first opening.
Claim 25
Independent Claim
92 words
An apparatus for allowing uniform flow of underfill material in interstices between a semiconductor device and a substrate, the apparatus comprising: a first dam adjacent a first section of the semiconductor device and a second dam adjacent a second section of the semiconductor device; an underfill dispenser positioned proximate the first dam which injects underfill material into the interstices between the semiconductor device and the substrate; and a vacuum cup positioned proximate the second dam, wherein the vacuum cup provides a continuous suction force to draw the underfill material throughout the interstices.
Claim 26
Independent Claim
92 words
An apparatus for allowing uniform flow of underfill material in interstices between a semiconductor device and a substrate, the apparatus comprising: a first dam adjacent a first section of the semiconductor device and a second dam adjacent a second section of the semiconductor device; an underfill dispenser positioned proximate the first dam which injects underfill material into the interstices between the semiconductor device and the substrate; and a vacuum cup positioned proximate the second dam, wherein the vacuum cup provides a continuous suction force to draw the underfill material throughout the interstices.
Claim 27
Dependent Claim
19 words
The apparatus of claim 23, wherein the underfill dispenser is located at a first corner of the semiconductor device.
Claim 28
Dependent Claim
16 words
The apparatus of claim 24, wherein the vacuum cup is located cater-cornered from the underfill dispenser.
Claim 29
Dependent Claim
14 words
The apparatus of claim 23, wherein the underfill material is drawn using a vacuum.
Claim 30
Dependent Claim
20 words
The apparatus of claim 23, wherein the vacuum cup creates a seal with the first dam and the second dam.
Claim 31
Dependent Claim
13 words
The apparatus of claim 23, wherein the first and second dams are molded.
Claim 32
Dependent Claim
16 words
The apparatus of claim 23, wherein the first and second dams have cross-sections resembling gaussian distributions.
Claim 33
Dependent Claim
19 words
The apparatus of claim 23, wherein the first and second dams are at least as high as the interstices.
Claim 34
Independent Claim
53 words
A device for obtaining a void-free underfill in the space between a semiconductor device and a substrate, the device comprising: means for substantially enclosing the semiconductor device; means for injecting underfill material into the space between the semiconductor device and the substrate; and means for continuously drawing the underfill material throughout the space.
Claim 35
Independent Claim
53 words
A device for obtaining a void-free underfill in the space between a semiconductor device and a substrate, the device comprising: means for substantially enclosing the semiconductor device; means for injecting underfill material into the space between the semiconductor device and the substrate; and means for continuously drawing the underfill material throughout the space.
Claim 36
Dependent Claim
36 words
The device of claim 31, wherein the means for substantially enclosing the semiconductor device comprises a dam extending from the substrate around the perimeter of the semiconductor device, the dam having at least two openings therein.
Claim 37
Dependent Claim
15 words
The device of claim 32, wherein the openings are formed at corners of the dam.
Claim 38
Dependent Claim
80 words
A process for underfilling a device on a substrate comprising: positioning the device on a substrate such that a space is created between the device and the substrate, the device having a plurality of sides; enclosing the plurality of sides of the device with a dam; inserting an underfill material into an aperture in the substrate within the area beneath the device, and drawing the underfill material into the space toward an opening in the dam with a continuous vacuum.
Claim 39
Dependent Claim
80 words
A process for underfilling a device on a substrate comprising: positioning the device on a substrate such that a space is created between the device and the substrate, the device having a plurality of sides; enclosing the plurality of sides of the device with a dam; inserting an underfill material into an aperture in the substrate within the area beneath the device, and drawing the underfill material into the space toward an opening in the dam with a continuous vacuum.
Claim 40
Dependent Claim
20 words
The process of claim 34, wherein the dam creates a seal against the plurality of sides of the semiconductor device.
Claim 41
Dependent Claim
17 words
The process of claim 34, wherein the semiconductor device and the dam have a generally rectangular shape.
Claim 42
Dependent Claim
16 words
The process of claim 36, wherein the opening is located at a corner of the dam.
Claim 43
Dependent Claim
14 words
The process of claim 34, wherein the underfill material is drawn using a vacuum.
Claim 44
Dependent Claim
14 words
The process of claim 38, wherein the vacuum is applied by a vacuum cup.
Claim 45
Dependent Claim
15 words
The process of claim 39, wherein the vacuum cup creates a seal with the dam.
Claim 46
Dependent Claim
18 words
The process of claim 34, wherein the vacuum is applied to a plurality of openings in the dam.
Claim 47
Independent Claim
93 words
A device mounted to a substrate comprising: a dam connected to the substrate, the dam substantially enclosing the device and having at least a first opening at a first corner of the device and having at least a second opening at a second corner of the device; and an underfill material positioned within a gap between the device and the substrate, the underfill material increasing the mounting strength of the device to the substrate, wherein the underfill material is drawn into the gap between the device and the substrate using a continuous vacuum.
Claim 48
Independent Claim
93 words
A device mounted to a substrate comprising: a dam connected to the substrate, the dam substantially enclosing the device and having at least a first opening at a first corner of the device and having at least a second opening at a second corner of the device; and an underfill material positioned within a gap between the device and the substrate, the underfill material increasing the mounting strength of the device to the substrate, wherein the underfill material is drawn into the gap between the device and the substrate using a continuous vacuum.
Claim 49
Dependent Claim
16 words
The device of claim 42, wherein the second corner is diagonally across from the first corner.
Claim 50
Dependent Claim
13 words
The device of claim 42, wherein the dam is made of epoxy resin.
Claim 51
Dependent Claim
31 words
The device of claim 42, wherein the dam has a third opening at a third corner of the device and having a fourth opening at a fourth corner of the device.
Claim 52
Dependent Claim
116 words
A semiconductor mounting device comprising: a substrate having a plurality of electrical contacts; a semiconductor device connected to the plurality of electrical contacts of the substrate such that a gap is formed between the semiconductor device and the substrate; a first dam positioned proximate a first side and a second side of the semiconductor device; a second dam positioned proximate a third side and a fourth side of the semiconductor device, and an underfill material positioned within the gap formed between the semiconductor device and the substrate to completely fill the gap, the underfill material extending from the first dam to the second dam, wherein the underfill material flows into the gap while applying a vacuum.
Claim 53
Dependent Claim
116 words
A semiconductor mounting device comprising: a substrate having a plurality of electrical contacts; a semiconductor device connected to the plurality of electrical contacts of the substrate such that a gap is formed between the semiconductor device and the substrate; a first dam positioned proximate a first side and a second side of the semiconductor device; a second dam positioned proximate a third side and a fourth side of the semiconductor device, and an underfill material positioned within the gap formed between the semiconductor device and the substrate to completely fill the gap, the underfill material extending from the first dam to the second dam, wherein the underfill material flows into the gap while applying a vacuum.
Claim 54
Dependent Claim
19 words
The semiconductor mounting device of claim 46, wherein the first and second dams are formed at approximate right angles.
Claim 55
Dependent Claim
18 words
The semiconductor mounting device of claim 46, wherein the first and second dams substantially enclose the semiconductor device.
Claim 56
Dependent Claim
25 words
The semiconductor mounting device of claim 46, further comprising openings between the first and second dams at a plurality of corners of the semiconductor device.
Claim 57
Dependent Claim
20 words
The semiconductor mounting device of claim 46, wherein the first and second dams stops the flow of the underfill material.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2003-04-11 | 2003-10-11 | 2004-04-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-04-11 | 2007-10-11 | 2008-04-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-04-11 | 2011-10-11 | 2012-04-11 | $7700.00 | Window Closed / Lapsed |