US5348913A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Methods for encapsulating electronic devices
Assignee: Nokia Bell Labs
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Filing: 1993-08-06
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Granted: 1994-09-20
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Expires: 2013-08-06
Abstract
Abstract In a preferred embodiment of the invention, a substrate (11) is cleaned by immersing it in an organic solvent (17) and subjecting it to acoustic energy, immersing it in alcohol, immersing it in a surfactant, subjecting it to a cascading rinse in deionized water, baking it (FIG. 3 ), and thereafter subjecting it to ultraviolet light in an ozone ambient (FIG. 4). When the foregoing steps are followed, the contact angle is significantly reduced, and an encapsulant (14) that is thereafter applied provides more reliable protection to an encapsulated device (12) from outside contaminants.
Inventors
- 👤 Richard McBride
- 👤 Ching-Ping Wong
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 09:16
CPC Classifications
H; H10; H10W; H10W74/00; H10W74/01; H10W99/00; Y; Y10; Y10S; Y10S148/00; Y10S148/017; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49124; Y10T29/4913; Y10T29/49146
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
114 words
A method for encapsulating an electronic device supported on a substrate comprising the steps of: cleaning the substrate; mounting an electronic device on one surface of the substrate; encasing the electronic device in a fluid encapsulant; and causing the encapsulant to harden and to adhere to both the substrate and the device; wherein the cleaning step comprises the steps of: immersing the substrate in an organic solvent; subjecting the immersed substrate to acoustic energy; removing the organic solvent from the substrate; and exposing the substrate to ultraviolet light in an environment containing ozone to provide to the substrate a relatively low contact angle, thereby to increase wetting of the substrate by the fluid encapsulant.
Claim 2
Independent Claim
114 words
A method for encapsulating an electronic device supported on a substrate comprising the steps of: cleaning the substrate; mounting an electronic device on one surface of the substrate; encasing the electronic device in a fluid encapsulant; and causing the encapsulant to harden and to adhere to both the substrate and the device; wherein the cleaning step comprises the steps of: immersing the substrate in an organic solvent; subjecting the immersed substrate to acoustic energy; removing the organic solvent from the substrate; and exposing the substrate to ultraviolet light in an environment containing ozone to provide to the substrate a relatively low contact angle, thereby to increase wetting of the substrate by the fluid encapsulant.
Claim 3
Dependent Claim
20 words
The method of claim 1 wherein: the step of removing the organic solvent comprises the step of baking the substrate.
Claim 4
Dependent Claim
23 words
The method of claim 2 wherein: prior to baking, the substrate is immersed in an alcohol while subjecting the substrate to acoustic energy.
Claim 5
Dependent Claim
19 words
The method of claim 2 wherein: prior to baking, the substrate is subjected to a rinse in deionized water.
Claim 6
Dependent Claim
25 words
The method of claim 3 wherein: after said immersing in alcohol and prior to baking, the substrate is subjected to a rinse in deionized water.
Claim 7
Dependent Claim
23 words
The method of claim 5 wherein: prior to the water rinse and after immersing in alcohol, the substrate is immersed in a surfactant.
Claim 8
Dependent Claim
17 words
The method of claim 6 wherein: the substrate is subjected to ultraviolet radiation for about five minutes.
Claim 9
Dependent Claim
15 words
The method of claim 7 wherein: the cleaning step occurs prior to the mounting step.
Claim 10
Dependent Claim
24 words
The method of claim 7 wherein: the cleaning step occurs after the mounting step, whereby the electronic device is cleaned along with the substrate.
Claim 11
Dependent Claim
17 words
The method of claim 6 wherein: while immersed in surfactant, the substrate is subjected to acoustic energy.
Claim 12
Independent Claim
111 words
A method for encapsulating an electronic device supported on a first surface of a substrate comprising the steps of: immersing the substrate in an organic solvent; subjecting the immersed substrate to acoustic energy; removing the organic solvent from the substrate; providing to the first surface of the substrate a relatively low contact angle comprising the step of exposing the first surface of the substrate to ultraviolet light in an environment containing ozone; completely encasing the electronic device in a fluid encapsulant, the fluid encapsulant covering at least part of the first surface of the substrate; and causing the encapsulant to harden and to adhere to both the substrate and the device.
Claim 13
Independent Claim
111 words
A method for encapsulating an electronic device supported on a first surface of a substrate comprising the steps of: immersing the substrate in an organic solvent; subjecting the immersed substrate to acoustic energy; removing the organic solvent from the substrate; providing to the first surface of the substrate a relatively low contact angle comprising the step of exposing the first surface of the substrate to ultraviolet light in an environment containing ozone; completely encasing the electronic device in a fluid encapsulant, the fluid encapsulant covering at least part of the first surface of the substrate; and causing the encapsulant to harden and to adhere to both the substrate and the device.
Claim 14
Dependent Claim
38 words
The method of claim 11 wherein: the fluid encapsulant is an uncured polymer precursor; and the step of causing the encapsulant to harden comprises the step of polymerizing the fluid encapsulant to cause it to become a solid.
Claim 15
Dependent Claim
35 words
The method of claim 12 wherein: the electronic device is an integrated circuit; and the substrate is selected from the group consisting of Si, SiO 2 , SiN, SiON, ceramic, and a III-V semiconductor compound.
Claim 16
Dependent Claim
21 words
The method of claim 12 wherein: said encapsulant is selected from the group consisting of silicone, epoxy, polyimide, Parylene and polyurethane.
Claim 17
Dependent Claim
22 words
The method of claim 14 wherein: said substrate is selected from the group consisting of SiO 2 , SiN, SiON and ceramic.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1997-09-19 | 1998-03-21 | 1998-09-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-09-19 | 2002-03-21 | 2002-09-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-09-19 | 2006-03-21 | 2006-09-20 | $7700.00 | Window Closed / Lapsed |