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US5357673A Expired / Lapsed US ⏱️ 0.0 years remaining

Semiconductor device encapsulation method

Assignee: Aumovio Systems Inc
•
Filing: 1993-10-01
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Granted: 1994-10-25
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Expires: 2013-10-01
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Abstract

Abstract In a semiconductor device encapsulation assembly (50; 60), a semiconductor device (21), preferably a pressure transducer, is mounted on a base (11) in a cavity (20) formed by the base and surrounding walls (15). Electrical connections, preferably wire bonds (27), connect the semiconductor device to conductor paths (28) on the base within the cavity. An encapsulation material comprising a thixotropic fluorosiloxane material (51; 61) is applied in the cavity and completely covers the semiconductor device and the electrical connections. This structure enables the semiconductor device to withstand typical automotive contaminants, such as mild acids and gasoline, while also preventing erratic semiconductor device operation due to bubbles which may be drawn into the encapsulation material.

Inventors

  • 👤 Anthony J. Polak
  • 👤 David J. Schifferle
  • 👤 Tom Wang

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 12:01
CPC Classifications
H; H10; H10W; H10W74/00; H10W74/40; H10W74/47; H10W74/476; H10W72/00; H10W72/30; H10W74/01; H10W74/10; H10W74/111; H10W74/114; H10W90/00; H10W72/071; H10W72/073; H10W72/07331; H10W72/07336; H10W72/07351; H10W72/07352; H10W72/321; H10W72/50; H10W72/551; H10W72/552; H10W72/5522; H10W72/851; H10W72/874; H10W72/884; H10W90/701; H10W90/731; H10W90/734; H10W90/751; H10W90/754; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49124; Y10T29/4913; Y10T29/49144

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 148 words
A method for providing a semiconductor device encapsulation assembly comprising the steps of: providing a protective outer structure having a base and surrounding walls which form an internal cavity open at one end and otherwise sealed; providing a plurality of conductor paths on said base such that some of these paths are within said cavity; mounting a semiconductor device on said base such that said semiconductor device is in said cavity; providing electrical connections for electrically connecting said semiconductor device to said plurality of conductor paths on said base, said cavity with said base, said surrounding walls, said conductor paths, said semiconductor device and said provided electrical connections forming a pre-existing assembly; and applying in an initial liquid form within said cavity in said are-existing assembly an encapsulation material which completely covers said semiconductor device and said electrical connections, wherein said encapsulation material comprises a thixotropic flurosiloxane material.
Claim 2
Independent Claim 148 words
A method for providing a semiconductor device encapsulation assembly comprising the steps of: providing a protective outer structure having a base and surrounding walls which form an internal cavity open at one end and otherwise sealed; providing a plurality of conductor paths on said base such that some of these paths are within said cavity; mounting a semiconductor device on said base such that said semiconductor device is in said cavity; providing electrical connections for electrically connecting said semiconductor device to said plurality of conductor paths on said base, said cavity with said base, said surrounding walls, said conductor paths, said semiconductor device and said provided electrical connections forming a pre-existing assembly; and applying in an initial liquid form within said cavity in said are-existing assembly an encapsulation material which completely covers said semiconductor device and said electrical connections, wherein said encapsulation material comprises a thixotropic flurosiloxane material.
Claim 3
Dependent Claim 14 words
A method according to claim 1 wherein said semiconductor device is a pressure transducer.
Claim 4
Dependent Claim 27 words
A method according to claim 2 which includes the step of curing said encapsulation material after its application to said semiconductor device and said electrical connection means.
Claim 5
Dependent Claim 30 words
A method according to claim 3 wherein said step of providing said protective outer structure includes the step of soldering said base to said walls to form a hermetic seal.
Claim 6
Dependent Claim 31 words
A method according to claim 4 wherein said electrical connections comprise a plurality of wire bonds from bonding pads on a top surface of said semiconductor device to said conductor paths.
Claim 7
Dependent Claim 39 words
A method according to claim 5 wherein the step of mounting said semiconductor device in said cavity on said base comprises the step of mounting and bonding a bottom surface of said semiconductor device to metalization on said base.
Claim 8
Dependent Claim 19 words
A method according to claim 6 wherein said applied encapsulation material comprises a mixture of polyfluorosiloxane and fumed silica.
Claim 9
Dependent Claim 14 words
A method according to claim 1 wherein said thixotropic encapsulation material includes fumed silica.
Claim 10
Dependent Claim 28 words
A method according to claim 8 wherein said encapsulation material comprises a mixture of said flurosiloxane material and fumed silica in an approximate 100; 2-4 ratio by weight.
Claim 11
Dependent Claim 23 words
A method according to claim 1 wherein said applying step comprises applying said thixotropic encapsulation material directly in contact with said semiconductor device.

References Cited (Backward Citations)

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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) 1997-10-24 1998-04-25 1998-10-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2001-10-24 2002-04-25 2002-10-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2005-10-24 2006-04-25 2006-10-25 $7700.00 Window Closed / Lapsed

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