Thermal transient suppression material and method of production

• US 7,498,376 B2
• Filed: 06/23/2004
• Issued: 03/03/2009
• Est. Priority Date: 06/23/2004
• Status: Expired due to Fees

• Current Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Original Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Inventors: Myers, Bruce A., Chaudhuri, Arun K.
• Primary Examiner(s): Cain; Edward J
• Application Number:
  US10/874,654
• Publication Number:
  US 20050287352A1
• Time in Patent Office: 1,714 Days
• Field of Search: 524/275, 524/277, 524/487, 524/488, 524/489
• US Class Current: 524/487
• CPC Class Codes: C09K 5/063 Materials absorbing or liberating heat during crystallisation; Heat storage materials
• CPC Class Codes: C09K 5/14 Solid materials, e.g. powdery or granular
• CPC Class Codes: H01L 23/3737 Organic materials with or without a thermoconductive filler
• CPC Class Codes: H01L 23/4275 by melting or evaporation of solids
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: Y02P 20/129 Energy recovery, e.g. by cogeneration, H2recovery or pressure recovery turbines
• CPC Class Codes: Y10T 428/25 Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles

Abstract

The present invention provides a high performance polymer-base material capable of dissipating transient thermal energy generated by an electronic module, such as a heat-generating power device. The methods of the present invention involve adding a suitable thinner to reduce the viscosity and increase the volume of a polymer-base matrix material so that a large amount of thermal absorbing particles may be added. The final cured product may have a filler content of more than 80 weight %. Further, the present invention provides a new and reduced cost formulation of a polymer-base thermal transient suppression material containing organic wax particles.

Claims

1. A polymer-base material for encapsulating an electronic module comprising

a silicone polymer matrix material;

and

filler particles dispersed in the matrix material, wherein the filler particles include organic wax particles and dielectric particles, and wherein a ratio of polymer matrix material to organic wax to dielectric particles is 34;

26;

40.

2. The polymer-base material of claim 1, wherein the organic wax particles are made of a polypropylene compound.

3. A method for producing a thermal transient suppression material on a heat generating electronic module comprising:

mixing a curable silicone compound and a suitable thinner to form a thinned matrix-forming material;

combining a filler to the thinned matrix-forming material to form a mixture, said filler being selected form the group consisting of dielectrically coated solder alloy particles and wax particles;

applying the mixture onto the heat generating electronic module; and

evaporating the thinner from the coating, and curing the curable compound to form a thermal transient suppression material, said a thermal transient suppression material composed of the filler dispersed in a cured matrix material.

4. A method as claimed in claim 3, wherein the suitable thinner comprises Octamethyl trisiloxane, tetradecamethyl hexasloxane and hexamethyl disiloxane.

5. A method as claimed in claim 3, wherein the mixture comprises up to 80 weight percent of the thinned matrix-forming material.

6. A method as claimed in claim 3, further comprising, prior applying the mixture onto the hear generating electronic module, adding a dielectric filler, wherein the dielectric filler is a ceramic material.

7. A method as claimed in claim 6, wherein the dielectric filler is alumina, boron nitride, silicon carbide, silicon nitride or a combination thereof.

8. A method as claimed in claim 3, wherein said thermal transient suppression material comprises more than 80 weight percent of said filler.

9. A method as claimed in claim 3, wherein said thermal transient suppression material has a thickness of about 0.05 mm or less.

10. A method as claimed in claim 3, wherein the filler comprises synthetic wax particles.

11. A method as in claim 10, wherein the wax particles are made of a polypropylene compound.

12. A method as in claim 10, wherein the thermal transient suppression material comprises about 60 to about 80 weight percent wax particles.