[go: up one dir, main page]
More Web Proxy on the site http://driver.im/

USRE39992E1 - Morphing fillers and thermal interface materials - Google Patents

Morphing fillers and thermal interface materials Download PDF

Info

Publication number
USRE39992E1
USRE39992E1 US11/122,210 US12221005A USRE39992E US RE39992 E1 USRE39992 E1 US RE39992E1 US 12221005 A US12221005 A US 12221005A US RE39992 E USRE39992 E US RE39992E
Authority
US
United States
Prior art keywords
thermally conductive
alloy
paste
mechanically compliant
pad
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime, expires
Application number
US11/122,210
Inventor
Sanjay Misra
GM Fazley Elahee
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Henkel IP and Holding GmbH
Original Assignee
Bergquist Co Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US09/865,778 external-priority patent/US6649325B1/en
Priority claimed from US09/946,879 external-priority patent/US6797758B2/en
Application filed by Bergquist Co Inc filed Critical Bergquist Co Inc
Priority to US11/122,210 priority Critical patent/USRE39992E1/en
Application granted granted Critical
Publication of USRE39992E1 publication Critical patent/USRE39992E1/en
Assigned to THE BERGQUIST COMPANY reassignment THE BERGQUIST COMPANY ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: ELAHEE, GM FAZLEY, MISRA, SANJAY
Assigned to Henkel IP & Holding GmbH reassignment Henkel IP & Holding GmbH ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: THE BERGQUIST COMPANY
Adjusted expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L23/00Details of semiconductor or other solid state devices
    • H01L23/34Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements
    • H01L23/36Selection of materials, or shaping, to facilitate cooling or heating, e.g. heatsinks
    • H01L23/373Cooling facilitated by selection of materials for the device or materials for thermal expansion adaptation, e.g. carbon
    • H01L23/3737Organic materials with or without a thermoconductive filler
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L23/00Details of semiconductor or other solid state devices
    • H01L23/34Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements
    • H01L23/36Selection of materials, or shaping, to facilitate cooling or heating, e.g. heatsinks
    • H01L23/373Cooling facilitated by selection of materials for the device or materials for thermal expansion adaptation, e.g. carbon
    • H01L23/3736Metallic materials
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L24/00Arrangements for connecting or disconnecting semiconductor or solid-state bodies; Methods or apparatus related thereto
    • H01L24/01Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L24/26Layer connectors, e.g. plate connectors, solder or adhesive layers; Manufacturing methods related thereto
    • H01L24/28Structure, shape, material or disposition of the layer connectors prior to the connecting process
    • H01L24/29Structure, shape, material or disposition of the layer connectors prior to the connecting process of an individual layer connector
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28HEAT EXCHANGE IN GENERAL
    • F28FDETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F13/00Arrangements for modifying heat-transfer, e.g. increasing, decreasing
    • F28F2013/005Thermal joints
    • F28F2013/006Heat conductive materials
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/26Layer connectors, e.g. plate connectors, solder or adhesive layers; Manufacturing methods related thereto
    • H01L2224/28Structure, shape, material or disposition of the layer connectors prior to the connecting process
    • H01L2224/29Structure, shape, material or disposition of the layer connectors prior to the connecting process of an individual layer connector
    • H01L2224/29001Core members of the layer connector
    • H01L2224/29099Material
    • H01L2224/29198Material with a principal constituent of the material being a combination of two or more materials in the form of a matrix with a filler, i.e. being a hybrid material, e.g. segmented structures, foams
    • H01L2224/29199Material of the matrix
    • H01L2224/2929Material of the matrix with a principal constituent of the material being a polymer, e.g. polyester, phenolic based polymer, epoxy
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/26Layer connectors, e.g. plate connectors, solder or adhesive layers; Manufacturing methods related thereto
    • H01L2224/28Structure, shape, material or disposition of the layer connectors prior to the connecting process
    • H01L2224/29Structure, shape, material or disposition of the layer connectors prior to the connecting process of an individual layer connector
    • H01L2224/29001Core members of the layer connector
    • H01L2224/29099Material
    • H01L2224/29198Material with a principal constituent of the material being a combination of two or more materials in the form of a matrix with a filler, i.e. being a hybrid material, e.g. segmented structures, foams
    • H01L2224/29298Fillers
    • H01L2224/29299Base material
    • H01L2224/29386Base material with a principal constituent of the material being a non metallic, non metalloid inorganic material
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/26Layer connectors, e.g. plate connectors, solder or adhesive layers; Manufacturing methods related thereto
    • H01L2224/28Structure, shape, material or disposition of the layer connectors prior to the connecting process
    • H01L2224/29Structure, shape, material or disposition of the layer connectors prior to the connecting process of an individual layer connector
    • H01L2224/29001Core members of the layer connector
    • H01L2224/29099Material
    • H01L2224/29198Material with a principal constituent of the material being a combination of two or more materials in the form of a matrix with a filler, i.e. being a hybrid material, e.g. segmented structures, foams
    • H01L2224/29298Fillers
    • H01L2224/29399Coating material
    • H01L2224/294Coating material with a principal constituent of the material being a metal or a metalloid, e.g. boron [B], silicon [Si], germanium [Ge], arsenic [As], antimony [Sb], tellurium [Te] and polonium [Po], and alloys thereof
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/26Layer connectors, e.g. plate connectors, solder or adhesive layers; Manufacturing methods related thereto
    • H01L2224/31Structure, shape, material or disposition of the layer connectors after the connecting process
    • H01L2224/32Structure, shape, material or disposition of the layer connectors after the connecting process of an individual layer connector
    • H01L2224/321Disposition
    • H01L2224/32151Disposition the layer connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive
    • H01L2224/32221Disposition the layer connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked
    • H01L2224/32245Disposition the layer connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked the item being metallic
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/013Alloys
    • H01L2924/0132Binary Alloys
    • H01L2924/01322Eutectic Alloys, i.e. obtained by a liquid transforming into two solid phases
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/15Details of package parts other than the semiconductor or other solid state devices to be connected
    • H01L2924/151Die mounting substrate
    • H01L2924/156Material
    • H01L2924/157Material with a principal constituent of the material being a metal or a metalloid, e.g. boron [B], silicon [Si], germanium [Ge], arsenic [As], antimony [Sb], tellurium [Te] and polonium [Po], and alloys thereof
    • H01L2924/15738Material with a principal constituent of the material being a metal or a metalloid, e.g. boron [B], silicon [Si], germanium [Ge], arsenic [As], antimony [Sb], tellurium [Te] and polonium [Po], and alloys thereof the principal constituent melting at a temperature of greater than or equal to 950 C and less than 1550 C
    • H01L2924/15747Copper [Cu] as principal constituent
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/30Technical effects
    • H01L2924/301Electrical effects
    • H01L2924/3011Impedance

Definitions

  • the present invention is a continuation-in-part of application Ser. No. 09/543,661, filed Apr. 5, 2000, now U.S. Pat. No. 6,339,120 entitled “METHOD OF PREPARING THERMALLY CONDUCTIVE COMPOUNDS BY LIQUID METAL BRIDGED PARTICLE CLUSTERS”, and continuation-in-part application Ser. No. 09/690,994, filed Oct. 17, 2000, now U.S. Pat. No. 6,624,224 entitled “METHOD OF PREPARING THERMALLY CONDUCTIVE COMPOUNDS BY LIQUID METAL BRIDGED PARTICLE CLUSTERS”, and application Ser. No. 09/865,778, filed May 25, 2001, now U.S. Pat. No.
  • the present invention relates generally to a method of preparing thermally conductive interface materials and compounds for improving heat transfer from a heat generating semiconductor device to a heat dissipator device such as a heat sink or heat spreader. More specifically, the present invention relates to a method and/or technique for preparing a mixture of an indium alloy blended with a polymer matrix, the polymer being in the solid phase at room temperatures and with both the alloy and the polymer having a melting temperature of between about 40° C. and 120° C., preferably between about 40° C. and 100° C.
  • the present invention involves a process for blending a normally solid polymeric matrix with a low melting alloy of indium metal for forming an improved thermal management system for use in combination with high performance semiconductor devices.
  • the thermal impedance or resistance created between two components in a typical electronic thermal management assembly is increased when surface imperfections are present on the opposed surfaces of the two components.
  • the causes of poor physical contact typically lie with macroscopic warpage of one or both surfaces, surface roughness, or other non-flat characteristics created on one or both of the opposed contact surfaces. Areas of non-intimate surface contact result in the creation of air-filled voids which are, of course, exceptionally poor conductors of heat.
  • High thermal impedance resulting from poor thermal contact results in undesirable heating of electronic components which in turn accelerates the rate of failure of the components such as semiconductor components and comprising the assembly.
  • Replacement of air gaps or voids with a thermally conducting medium comprising a good thermal management system has been found to sharply reduce the thermal impedance and/or resistance.
  • thermally conductive pastes for use with heat generating semiconductor devices.
  • liquid metals were not readily adapted for this purpose, primarily because of problems created with the tendency of the liquid metal to form alloys and/or amalgams, which altered or modified the thermal and other physical properties of the mounting systems.
  • Other thermal interface materials are made by dispersing thermally conductive fillers in a polymer matrix. While most polymer matrices range in thermal conductivity from 0.1-0.2 W-m ⁇ 1 -K ⁇ , the properties of the fillers are quite varied.
  • improved interface materials have been developed based on incorporation of low melting alloys as fillers capable of altering their shape in response to heat and pressure.
  • these fillers are in solid phase, as is the polymer matrix, with this combination of features facilitating ease of handling.
  • these morphing fillers respond to heat and pressure by their ability to flow into and fill air gaps or voids that may be present in the matrix, thereby avoiding creation of standoff or poor particle-to-particle contact (see FIG. 2 ).
  • interfaces having thin cross-sections may be employed.
  • those dispersions utilizing only polymeric matrices having dispersed low melting alloys function well (see FIG. 3 ).
  • it is normally desirable to utilize highly thermally conductive particulate fillers in combinations with the low melting alloys in order to create large heat percolating clusters see for example FIG. 4 ).
  • an indium-containing alloy is selected which is in the solid phase at room temperature, while having a melt temperature of between about 40° C. and 120° C.
  • the alloy is then subjected to a size reduction operation—typically by emulsifying, while in molten phase, in the polymer matrix of interest.
  • a surface active agent may be added during the emulsification to enhance the rheological properties and dispersion stability.
  • the size reduction of the metal alloy may be accomplished by blow or impact, or alternatively by grinding or abrasion, under cryogenic conditions. Depending upon the particular type of equipment and conditions under which the particulate is formed, it may be possible to add the surface active agent to the working material while undergoing size reduction process.
  • the metallic powder can then be blended with a quantity of a matrix polymer which is likewise in the solid phase at room temperature, having a melt point of between about 40° and 100° C. to form a compliant pad.
  • the polymer matrix is preferably selected from the group consisting of paraffin, microwax, and silicone waxes.
  • the low melting alloy may also be blended with a particulate filler such as, for example, boron nitride or alumina with the resultant mixture being mechanically agitated in the presence of a compatible wetting agent to form a stable dispersion for ultimate blending with the polymer matrix.
  • melt temperatures for the polymer matrix and the metal alloy are both indicated as being between about 40° C. and 120° C.
  • a differential be maintained between the actual melt temperatures.
  • Other differential relationships may also be useful. While certain other metal alloys may be found useful, indium-based alloys are generally preferred for utilization in the present invention.
  • thermal interface compounds prepared in accordance with the present invention are such that conventional production handling techniques may be employed during assembly operations.
  • the compounds may be handled or formed into an interface device by stamping or they may be printed directly onto heat-transfer surfaces. Alternatively, they may be made into tapes that can be die-cut so as to be later applied directly onto the heat transfer surfaces.
  • compositions of materials useful as thermal interface compounds wherein a low melting metallic alloy is retained within a polymer matrix, and wherein each of these components is in the solid phase at room temperature, and has a melting temperature of between about 40° C. and 120° C. and preferably between about 40° C. and 100° C.
  • hard particulate fillers such as boron nitride and/or alumina
  • FIG. 1 is a demonstrative display of the performance of a prior art thermal interface utilizing a hard particulate within a conventional polymeric matrix, and demonstrating the non-responsive or non-compliant nature of the combination when subjected to the application of heat and pressure;
  • FIG. 2 is a view similar to FIG. 1 illustrating the response of a low melting point alloy within a conventional polymeric matrix, and showing the response when subjected to the application of heat and pressure;
  • FIG. 3 is a demonstrative sketch illustrating a metal alloy dispersed within a conventional polymeric matrix
  • FIG. 4 is a demonstrative sketch illustrating the arrangement of percolating clusters of a metal alloy in which a thermally conducting inorganic particulate is dispersed, with the alloy/particulate clusters being in turn disposed within a polymeric matrix;
  • FIG. 5 is a demonstrative sketch illustrating a low melting point alloy dispersed within a polymeric matrix and designed for accommodating surface areas which are small and/or flat and which lie between a heat generating semiconductor device and a heat sink;
  • FIG. 6 is a demonstrative sketch illustrating a percolating cluster of low melting point metal alloy blended with particulate, and held in place within a laterally disposed mechanical standoff for application as a thermal interface between surfaces of large warpage, it being noted that the presence of high thermal conductivity fillers assists in the creation of large heat percolating clusters;
  • FIG. 7 is a flow diagram illustrating the steps involved in a typical operation for preparing thermal interface devices in accordance with the present invention.
  • FIG. 8 is a graph demonstrating the change in thermal impedance versus temperature for the metal alloy and polymeric components of phase-change interface materials prepared in accordance with the present invention.
  • FIG. 9 is an illustration of a typical semiconductor mounted on a finned heat sink, and having the thermal interface of the present invention interposed between opposed surfaces of the semiconductor device and the heat sink.
  • an indium-containing alloy is initially selected with this alloy having a melt temperature of between about 40° C. and 100° C., it being understood that alloys having melt temperatures of up to about 120° C. may also find application.
  • the low melting indium alloy comprises indium alloys containing quantities of bismuth, tin, and/or zinc as set forth below.
  • the selected indium alloy is subjected to an emulsification step wherein the metal is reduced to a finely divided form. It is preferred that the metal alloy be reduced to particles which average about 1-100 ⁇ m in diameter.
  • the size reduction or emulsification may be undertaken in a high shear mixer, with the addition of a compatible surface active agent at a point in this step.
  • the metal particulate is blended with a polymer, with the blend being subsequently cured to form the polymeric matrix retainer.
  • the materials may be compounded in liquid state creating an emulsion with metal droplets dispersed in the polymer.
  • silanes, titanates, zirconates and/or assorted surface active agents are preferred to improve rheology and stability of the dispersion, and particularly for creating a hydrophobic barrier.
  • Surface treatments with surface active agents that work well for improving rheology as well as stability of the dispersion, especially against moisture, are alkyl functional silanes, such as for example octyl triethoxy silane (OTES).
  • OTES octyl triethoxy silane
  • MTMS methyltrimethoxy
  • compositions have been prepared, with numbers being by weight:
  • Formulations 3, 4 and 5 may be applied as coatings by typical coating techniques including hot stamp, screen printing, or applied to the heat transfer surface directly by other means. These coatings will typically have a cross-sectional thickness of less than about 10 mils.
  • those formulations containing a particulate filler such as Formulations 1, 2 and 6 may find particular application. These coatings may be applied to carriers such as glass or polymer fabrics, plastic films or metal foils. When supported, the coatings may be handled with ease, thereby facilitating their use in production.
  • Formula 3 is recommended, although those of Formula 4 and 5 are highly suited as well.
  • the metal droplet will deform completely so as to reduce contact resistance without increasing standoff. See for example the demonstrative dispersions illustrated in FIG. 5 .
  • formulations pursuant to Formula 1 are well suited, it being noted that this formulation has highly desirable thermal conductive properties.
  • the metal droplets present in the formulation will continue to function for reduction of contact resistance, while portions of the metallic component will be present in larger percolating clusters for enhanced transfer of thermal energy. See, for example, the demonstrative percolating cluster dispersions of FIG. 6 .
  • a thermal interface is prepared pursuant to any one selected formulation of Formulas 1 through 6 of Table II, with a thermal interface so prepared being employed in combination with a heat generating semiconductor device of conventional configuration.
  • the assembly 30 shown in FIG. 9 includes a heat generating semiconductor device or package illustrated at 31 having a heat sink, heat spreader, or other finned heat dissipating member illustrated at 32 .
  • a mechanically compliant thermally conductive interface 33 is interposed between the opposed surfaces of semiconductor device 31 and heat dissipating member 32 , prepared in accordance with the present invention.
  • FIG. 7 is a flow diagram setting forth the steps typically undertaken in accordance with the creation of thermally conductive interfaces in accordance with the present invention. As indicated, and as is apparent from the flow diagram, the alloy/particulate mixture is blended until the surfaces of the particulate are thoroughly wetted with a surface active agent, and thereafter an alloy/particulate/matrix formulation is prepared through the addition to a selected polymer, preferably one which is heated to a highly flowable condition or in the “B” stage of cure.
  • FIG. 7 is a flow chart illustrating the steps undertaken in preparing the thermal interfaces of the present invention commencing with the initial milling of the indium alloy, and identifying the steps that follow.
  • the preferred method is emulsification of the metal in molten form. This can either be done in-situ in the polymer matrix of interest or in another liquid medium, followed by separation and purification of the powder. Utilizing typical operating parameters, the powdered alloy is available in sizes ranging up to about 100 microns.
  • Surface treatment includes, preferably, the addition of a surface active agent such as, for example, octyl triethoxy silane (OTES) or methyl triethoxy silane (MTMS).
  • a surface active agent such as, for example, octyl triethoxy silane (OTES) or methyl triethoxy silane (MTMS).
  • OTES octyl triethoxy silane
  • MTMS methyl triethoxy silane
  • These silanes bind to the oxides which readily form of the surface of the metallic particles to create a hydrophobic barrier. Additionally, they compatibilize the particles with the polymer matrix and reduce particle aggregation.
  • titanates or zirconates such as, for example, the barium or calcium salt forms, may be used.
  • particulate materials such as boron nitride and alumina may typically be employed to improve the thermal conductivity and stability of the blend. These particulate components may be present in a range up to about 15% by volume, although blends containing up to about 50% by volume may be employed successfully.
  • the alloy coats the particulate, with the blending operation being undertaken with the alloy in the liquid phase.
  • the polymer matrix is preferably selected from paraffin, microwax, and silicone waxes comprising alkyl silicones.
  • microwax having a melting point of about 50-60° C. has been found particularly suited for this application.
  • this step by undertaken with both components in the liquid phase.
  • the materials are blended in a high shear mixer until the metal becomes thoroughly dispersed in the polymer, at which time it may be formed into the configuration desired for the thermal interface.
  • Conventional techniques for preparing the coating may be utilized, with this operation being compatible with most liquid phase treatment operations.
  • prior art thermal interfaces utilizing hard particulate within a conventional hard or firm polymeric matrix lacks the ability to flow under heat and pressure, and therefore results in a standoff between the adjacent or opposed surfaces.
  • FIG. 2 illustrates the performance and activity when a phase change filler is employed in a polymeric matrix, with the filler deforming and modifying its configuration under heat and pressure, thereby permitting the opposed surfaces to mate.
  • FIG. 3 demonstrates the dispersal of metal alloy particles within a polymer, with the configuration of the particulate being determined primarily by surface tension phenomena.
  • this figure demonstrates the presence of percolating clusters of inorganic particulate such as boron nitride confined within metal alloy, with the percolating effect being achieved through the merger of various individual particulate.
  • this figure demonstrates the utilization of a low melting metal alloy as a dispersion for small and flat surfaces, it being noted that the metal alloy conforms under the influence of heat and pressure to enhance the contact areas.
  • the curves illustrate the performance and properties of the polymer taken together with the metal alloy component in a typical thermal interface.
  • the phase change for the metal alloy component occurs at a temperature approximately 10° higher than that for the polymeric matrix. This has been found to be a workable arrangement with respect to temperature differentials pursuant to the present invention.
  • Boron nitride or alumina particulate preferably ranges in size from about 1 micron and up to about 40 microns in diameter or cross-sectional thickness. It will be observed that the platelet-like configuration of boron nitride in particular provides a highly desirable configuration and combination when wetted with liquid metal. The effective boron nitride particle is illustrated in FIG. 4 of the drawings. Viscosity control is also aided by this feature or property of boron nitride.
  • silicone wax utilized in the formulations of the examples is GP-533 (M.P. of 60° C.) (Genesee Polymer of Flint, Mich.), with these materials being, of course, commercially available.
  • a microwax employed is M-7332 (M.P. of 55° C.) (Moore and Munger of Shelton, Conn.).
  • Another polymer matrix used is a one-part soft reactive silicone elastomer (GE Toshiba Silicones of Tokyo, Japan).
  • One unusual and unexpected property or feature of formulations of the present invention is the electrical resistivity.
  • Formulation 1 When Formulation 1 is formed in a pad of thickness of 3-5 mils and interposed between opposed surfaces of a semiconductor device and a heat sink, the electrical resistivity of the pad has been found to be highly significant, having a value of up to about 10 12 ⁇ cm (Formulation 1, Table II).

Landscapes

  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Computer Hardware Design (AREA)
  • Power Engineering (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Physics & Mathematics (AREA)
  • Compositions Of Macromolecular Compounds (AREA)
  • Cooling Or The Like Of Semiconductors Or Solid State Devices (AREA)
  • Manufacture Of Metal Powder And Suspensions Thereof (AREA)
  • Polyesters Or Polycarbonates (AREA)
  • Conductive Materials (AREA)
  • Processes Of Treating Macromolecular Substances (AREA)
  • Powder Metallurgy (AREA)
  • Ceramic Products (AREA)

Abstract

A thermally conductive mechanically compliant pad including a quantity of gallium and/or indium alloy liquid at temperatures below about 120° C. and a boron nitride particulate solid blended into the liquid metal alloy to form a paste. The paste is then combined with a quantity of a matrix forming flowable plastic resin such as microwax, silicone wax, or other silicone polymer to form the thermally conductive mechanically compliant pad, the compliant pad comprising from between about 10% and 90% of metal alloy coated particulate, balance flowable plastic resin.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS
The present invention is a continuation-in-part of application Ser. No. 09/543,661, filed Apr. 5, 2000, now U.S. Pat. No. 6,339,120 entitled “METHOD OF PREPARING THERMALLY CONDUCTIVE COMPOUNDS BY LIQUID METAL BRIDGED PARTICLE CLUSTERS”, and continuation-in-part application Ser. No. 09/690,994, filed Oct. 17, 2000, now U.S. Pat. No. 6,624,224 entitled “METHOD OF PREPARING THERMALLY CONDUCTIVE COMPOUNDS BY LIQUID METAL BRIDGED PARTICLE CLUSTERS”, and application Ser. No. 09/865,778, filed May 25, 2001, now U.S. Pat. No. 6,649,325 entitled “THERMALLY CONDUCTIVE DIELECTRIC MOUNTS FOR PRINTED CIRCUITRY AND SEMICONDUCTOR DEVICES AND METHOD OF PREPARATION”, all of which are assigned to the same assignee as the present invention.
BACKGROUND OF THE INVENTION
The present invention relates generally to a method of preparing thermally conductive interface materials and compounds for improving heat transfer from a heat generating semiconductor device to a heat dissipator device such as a heat sink or heat spreader. More specifically, the present invention relates to a method and/or technique for preparing a mixture of an indium alloy blended with a polymer matrix, the polymer being in the solid phase at room temperatures and with both the alloy and the polymer having a melting temperature of between about 40° C. and 120° C., preferably between about 40° C. and 100° C. These blends of metal alloy and polymer have been found to sharply reduce the thermal resistance or impedance which typically arises from a less-than-perfect contact between the boundaries or surfaces of a thermal interface positioned between the components of the assembly. More particularly, the present invention involves a process for blending a normally solid polymeric matrix with a low melting alloy of indium metal for forming an improved thermal management system for use in combination with high performance semiconductor devices.
The thermal impedance or resistance created between two components in a typical electronic thermal management assembly is increased when surface imperfections are present on the opposed surfaces of the two components. The causes of poor physical contact typically lie with macroscopic warpage of one or both surfaces, surface roughness, or other non-flat characteristics created on one or both of the opposed contact surfaces. Areas of non-intimate surface contact result in the creation of air-filled voids which are, of course, exceptionally poor conductors of heat. High thermal impedance resulting from poor thermal contact results in undesirable heating of electronic components which in turn accelerates the rate of failure of the components such as semiconductor components and comprising the assembly. Replacement of air gaps or voids with a thermally conducting medium comprising a good thermal management system has been found to sharply reduce the thermal impedance and/or resistance.
In the past, liquid metals have been proposed for incorporation in thermally conductive pastes for use with heat generating semiconductor devices. In some cases, liquid metals were not readily adapted for this purpose, primarily because of problems created with the tendency of the liquid metal to form alloys and/or amalgams, which altered or modified the thermal and other physical properties of the mounting systems. Other thermal interface materials are made by dispersing thermally conductive fillers in a polymer matrix. While most polymer matrices range in thermal conductivity from 0.1-0.2 W-m−1-K, the properties of the fillers are quite varied. They include silica (2 W-m−1-K), zinc oxide (10-20 W-m−1-K), alumina (20-30 W-m−1-K), aluminum nitride (100 W-m−1-K), and boron nitride (200 W-m−1-K). When placed in the thermal joint, these compounds are intended to displace air and reduce overall thermal impedance. Addition of thermally conductive fillers, generally consisting of fine particulates, improved the thermal conductivity of the compound filling the voids.
In our copending application Ser. No. 09/543,661, a number of low melting alloys are disclosed which are highly effective for use as thermal interfaces in thermal management systems for enhancement of percolation of thermal energy. The present invention provides additional advantages in thermal interfaces through the use of certain selected polymer matrices for retention of the low melting alloy, the matrices having melting points which are also low and, preferably, relatively close to the melting points of the retained alloys. These polymers as well as the alloys are in solid phase at room temperature, and this feature facilitates ease of handling of the thermal interface particularly during production and use.
In accordance with the present invention, improved interface materials have been developed based on incorporation of low melting alloys as fillers capable of altering their shape in response to heat and pressure. At room temperature, these fillers are in solid phase, as is the polymer matrix, with this combination of features facilitating ease of handling. In addition, these morphing fillers respond to heat and pressure by their ability to flow into and fill air gaps or voids that may be present in the matrix, thereby avoiding creation of standoff or poor particle-to-particle contact (see FIG. 2).
In those applications where the opposed surface areas are small, or alternatively are relatively flat, interfaces having thin cross-sections may be employed. Typically, in such applications, those dispersions utilizing only polymeric matrices having dispersed low melting alloys function well (see FIG. 3). For interfaces employing a laterally disposed mechanical standoff, or those subject to large warpage, it is normally desirable to utilize highly thermally conductive particulate fillers in combinations with the low melting alloys in order to create large heat percolating clusters (see for example FIG. 4).
SUMMARY OF THE INVENTION
In accordance with the present invention, an indium-containing alloy is selected which is in the solid phase at room temperature, while having a melt temperature of between about 40° C. and 120° C. The alloy is then subjected to a size reduction operation—typically by emulsifying, while in molten phase, in the polymer matrix of interest. A surface active agent may be added during the emulsification to enhance the rheological properties and dispersion stability. Alternatively, the size reduction of the metal alloy may be accomplished by blow or impact, or alternatively by grinding or abrasion, under cryogenic conditions. Depending upon the particular type of equipment and conditions under which the particulate is formed, it may be possible to add the surface active agent to the working material while undergoing size reduction process. The metallic powder can then be blended with a quantity of a matrix polymer which is likewise in the solid phase at room temperature, having a melt point of between about 40° and 100° C. to form a compliant pad. The polymer matrix is preferably selected from the group consisting of paraffin, microwax, and silicone waxes. The low melting alloy may also be blended with a particulate filler such as, for example, boron nitride or alumina with the resultant mixture being mechanically agitated in the presence of a compatible wetting agent to form a stable dispersion for ultimate blending with the polymer matrix.
It should be noted that while the melt temperatures for the polymer matrix and the metal alloy are both indicated as being between about 40° C. and 120° C., it is desirable that a differential be maintained between the actual melt temperatures. For example, it has been found desirable to select a polymer matrix having a melting temperature which is approximately 10° C. lower than that of the metal alloy. Other differential relationships may also be useful. While certain other metal alloys may be found useful, indium-based alloys are generally preferred for utilization in the present invention.
The physical properties of thermal interface compounds prepared in accordance with the present invention are such that conventional production handling techniques may be employed during assembly operations. In this connection, the compounds may be handled or formed into an interface device by stamping or they may be printed directly onto heat-transfer surfaces. Alternatively, they may be made into tapes that can be die-cut so as to be later applied directly onto the heat transfer surfaces.
Therefore, it is a primary object of the present invention to provide compositions of materials useful as thermal interface compounds, wherein a low melting metallic alloy is retained within a polymer matrix, and wherein each of these components is in the solid phase at room temperature, and has a melting temperature of between about 40° C. and 120° C. and preferably between about 40° C. and 100° C.
It is a further object of the present invention to provide an improved combination of components utilized to form a composition which is useful as thermal interface compounds, and wherein hard particulate fillers such as boron nitride and/or alumina may be employed in combination with an indium alloy, and thereafter blended into and retained within a polymeric matrix.
It is yet a further object of the present invention to provide an improved thermal interface compound which is dry and solid at room temperature, and which changes to liquid phase at moderately elevated temperatures, thereby permitting the compounds to be easily handled utilizing conventional handling techniques and yet respond effectively in a thermal management application.
Other and further objects of the present invention will become apparent to those skilled in the art upon a study of the following specification, appended claims, and accompanying drawings.
IN THE DRAWINGS
FIG. 1 is a demonstrative display of the performance of a prior art thermal interface utilizing a hard particulate within a conventional polymeric matrix, and demonstrating the non-responsive or non-compliant nature of the combination when subjected to the application of heat and pressure;
FIG. 2 is a view similar to FIG. 1 illustrating the response of a low melting point alloy within a conventional polymeric matrix, and showing the response when subjected to the application of heat and pressure;
FIG. 3 is a demonstrative sketch illustrating a metal alloy dispersed within a conventional polymeric matrix;
FIG. 4 is a demonstrative sketch illustrating the arrangement of percolating clusters of a metal alloy in which a thermally conducting inorganic particulate is dispersed, with the alloy/particulate clusters being in turn disposed within a polymeric matrix;
FIG. 5 is a demonstrative sketch illustrating a low melting point alloy dispersed within a polymeric matrix and designed for accommodating surface areas which are small and/or flat and which lie between a heat generating semiconductor device and a heat sink;
FIG. 6 is a demonstrative sketch illustrating a percolating cluster of low melting point metal alloy blended with particulate, and held in place within a laterally disposed mechanical standoff for application as a thermal interface between surfaces of large warpage, it being noted that the presence of high thermal conductivity fillers assists in the creation of large heat percolating clusters;
FIG. 7 is a flow diagram illustrating the steps involved in a typical operation for preparing thermal interface devices in accordance with the present invention;
FIG. 8 is a graph demonstrating the change in thermal impedance versus temperature for the metal alloy and polymeric components of phase-change interface materials prepared in accordance with the present invention; and
FIG. 9 is an illustration of a typical semiconductor mounted on a finned heat sink, and having the thermal interface of the present invention interposed between opposed surfaces of the semiconductor device and the heat sink.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In carrying out the steps of the present invention, an indium-containing alloy is initially selected with this alloy having a melt temperature of between about 40° C. and 100° C., it being understood that alloys having melt temperatures of up to about 120° C. may also find application. Preferably, the low melting indium alloy comprises indium alloys containing quantities of bismuth, tin, and/or zinc as set forth below.
The selected indium alloy is subjected to an emulsification step wherein the metal is reduced to a finely divided form. It is preferred that the metal alloy be reduced to particles which average about 1-100 μm in diameter. The size reduction or emulsification may be undertaken in a high shear mixer, with the addition of a compatible surface active agent at a point in this step.
Following size reduction, the metal particulate is blended with a polymer, with the blend being subsequently cured to form the polymeric matrix retainer. Alternatively, the materials may be compounded in liquid state creating an emulsion with metal droplets dispersed in the polymer.
Specific Preferred Embodiments
In order to describe the preferred embodiments, the following examples are given:
TABLE I
Alloys which are prepared for use in the present
invention having the composition and melting points as
follows:
Melting
Indium Bismuth Sn Zinc Point
Alloy (%) (%) (%) (%) (° C.
1 51 32.5 16.5 0 60
2 66.3 33.7 0 0 70
3 26 57 17 0 79
4 52.2 0 46 1.8 108 
Surface Active Agents
As surface active agents, silanes, titanates, zirconates and/or assorted surface active agents are preferred to improve rheology and stability of the dispersion, and particularly for creating a hydrophobic barrier. Surface treatments with surface active agents that work well for improving rheology as well as stability of the dispersion, especially against moisture, are alkyl functional silanes, such as for example octyl triethoxy silane (OTES). Another example is methyltrimethoxy (MTMS) silane. These silanes bind to the oxides on the surface of the metal particles, creating a durable hydrophobic barrier. Additionally, these silanes compatibilize the particles with the polymer matrix and reduce particle aggregation.
The following compositions have been prepared, with numbers being by weight:
TABLE II
40 μm
Boron
Matrix Alloy 1 Nitride OTES
Parts Parts Parts Parts
by by by by
Formula weight Vol % weight Vol % weight Vol % weight Vol %
1 1001 30 1200 52 100 15 12 3
2 1001 34 1000 48 83 14 10 4
3 1001 35 1200 61 0 0 12 4
4 1001 40 1000 56 0 0 10 4
5 1002 35 1200 61 0 0 12 4
6 1003 30 1200 52 100 15 12 3
1silicone wax consisting of siloxane backbones with pendant alkyl chains and having a melting point of 60° C.
2microwax, melting point 60° C.
3soft silicone polymer consisting of a reactive siloxane elastomer.
Typical properties of the formulations are set forth in Table III:
TABLE III
Thermal
Conductivity Thermal Impedance4
Formula (W/m-K) (K-cm2/W
1 >7 0.25
2 5.0 0.20
3 1.8 0.20
6 >7 0.25
4ASTM D5470, flat surfaces, no mechanical standoff.
Thermal Management Applications
Compounds prepared pursuant to the formulations of Table III are varied. Formulations 3, 4 and 5, in particular, may be applied as coatings by typical coating techniques including hot stamp, screen printing, or applied to the heat transfer surface directly by other means. These coatings will typically have a cross-sectional thickness of less than about 10 mils.
For coatings of larger cross-section, those formulations containing a particulate filler, such as Formulations 1, 2 and 6 may find particular application. These coatings may be applied to carriers such as glass or polymer fabrics, plastic films or metal foils. When supported, the coatings may be handled with ease, thereby facilitating their use in production.
Heat Transfer Modes
For those applications which require intimate contact, i.e., where the contact line is desired to be as thin as possible, Formula 3 is recommended, although those of Formula 4 and 5 are highly suited as well. In each event, the metal droplet will deform completely so as to reduce contact resistance without increasing standoff. See for example the demonstrative dispersions illustrated in FIG. 5.
For those applications requiring mechanical, standoff, formulations pursuant to Formula 1 are well suited, it being noted that this formulation has highly desirable thermal conductive properties. In addition, the metal droplets present in the formulation will continue to function for reduction of contact resistance, while portions of the metallic component will be present in larger percolating clusters for enhanced transfer of thermal energy. See, for example, the demonstrative percolating cluster dispersions of FIG. 6.
Device Application
With attention now being directed to FIG. 9 of the drawings, a thermal interface is prepared pursuant to any one selected formulation of Formulas 1 through 6 of Table II, with a thermal interface so prepared being employed in combination with a heat generating semiconductor device of conventional configuration. Accordingly, the assembly 30 shown in FIG. 9, includes a heat generating semiconductor device or package illustrated at 31 having a heat sink, heat spreader, or other finned heat dissipating member illustrated at 32. Interposed between the opposed surfaces of semiconductor device 31 and heat dissipating member 32 is a mechanically compliant thermally conductive interface 33, prepared in accordance with the present invention.
FIG. 7 is a flow diagram setting forth the steps typically undertaken in accordance with the creation of thermally conductive interfaces in accordance with the present invention. As indicated, and as is apparent from the flow diagram, the alloy/particulate mixture is blended until the surfaces of the particulate are thoroughly wetted with a surface active agent, and thereafter an alloy/particulate/matrix formulation is prepared through the addition to a selected polymer, preferably one which is heated to a highly flowable condition or in the “B” stage of cure.
Typical Preparation Operation
As indicated above, FIG. 7 is a flow chart illustrating the steps undertaken in preparing the thermal interfaces of the present invention commencing with the initial milling of the indium alloy, and identifying the steps that follow.
Conversion of Alloy to Powdered Form
The preferred method is emulsification of the metal in molten form. This can either be done in-situ in the polymer matrix of interest or in another liquid medium, followed by separation and purification of the powder. Utilizing typical operating parameters, the powdered alloy is available in sizes ranging up to about 100 microns.
Surface Treatment
Surface treatment includes, preferably, the addition of a surface active agent such as, for example, octyl triethoxy silane (OTES) or methyl triethoxy silane (MTMS). These silanes bind to the oxides which readily form of the surface of the metallic particles to create a hydrophobic barrier. Additionally, they compatibilize the particles with the polymer matrix and reduce particle aggregation. Alternatively, or additionally, titanates or zirconates such as, for example, the barium or calcium salt forms, may be used.
Blending with Thermally Conductive Particulate
As indicated hereinabove, particulate materials such as boron nitride and alumina may typically be employed to improve the thermal conductivity and stability of the blend. These particulate components may be present in a range up to about 15% by volume, although blends containing up to about 50% by volume may be employed successfully. When blended, the alloy coats the particulate, with the blending operation being undertaken with the alloy in the liquid phase.
The Polymer Matrix
As indicated, the polymer matrix is preferably selected from paraffin, microwax, and silicone waxes comprising alkyl silicones. For most purposes microwax having a melting point of about 50-60° C. has been found particularly suited for this application. As indicated above, it is generally desirable to utilize a polymer matrix which undergoes a phase change at a temperature of about 10° C. lower than the phase change temperature of the alloy.
Blending Alloy with Polymer Matrix
It is generally preferred that this step by undertaken with both components in the liquid phase. As such, the materials are blended in a high shear mixer until the metal becomes thoroughly dispersed in the polymer, at which time it may be formed into the configuration desired for the thermal interface. Conventional techniques for preparing the coating may be utilized, with this operation being compatible with most liquid phase treatment operations.
Properties of Thermal Interfaces
As illustrated in FIG. 1, prior art thermal interfaces utilizing hard particulate within a conventional hard or firm polymeric matrix lacks the ability to flow under heat and pressure, and therefore results in a standoff between the adjacent or opposed surfaces.
FIG. 2 illustrates the performance and activity when a phase change filler is employed in a polymeric matrix, with the filler deforming and modifying its configuration under heat and pressure, thereby permitting the opposed surfaces to mate.
FIG. 3 demonstrates the dispersal of metal alloy particles within a polymer, with the configuration of the particulate being determined primarily by surface tension phenomena.
With reference to FIG. 4, this figure demonstrates the presence of percolating clusters of inorganic particulate such as boron nitride confined within metal alloy, with the percolating effect being achieved through the merger of various individual particulate.
With attention being directed to FIG. 5, this figure demonstrates the utilization of a low melting metal alloy as a dispersion for small and flat surfaces, it being noted that the metal alloy conforms under the influence of heat and pressure to enhance the contact areas.
With reference to FIG. 6, it will be observed that a percolating cluster of dispersions of metal alloy/inorganic particulate retained within the confines of laterally dispersed mechanical standoff elements 40-40 in order to accommodate larger area surfaces or those subject to large warpage.
With attention now being directed to FIG. 8 of the drawings, it will be noted that the curves illustrate the performance and properties of the polymer taken together with the metal alloy component in a typical thermal interface. As indicated, the phase change for the metal alloy component occurs at a temperature approximately 10° higher than that for the polymeric matrix. This has been found to be a workable arrangement with respect to temperature differentials pursuant to the present invention.
General Commentary
Boron nitride or alumina particulate preferably ranges in size from about 1 micron and up to about 40 microns in diameter or cross-sectional thickness. It will be observed that the platelet-like configuration of boron nitride in particular provides a highly desirable configuration and combination when wetted with liquid metal. The effective boron nitride particle is illustrated in FIG. 4 of the drawings. Viscosity control is also aided by this feature or property of boron nitride.
One silicone wax utilized in the formulations of the examples is GP-533 (M.P. of 60° C.) (Genesee Polymer of Flint, Mich.), with these materials being, of course, commercially available. A microwax employed is M-7332 (M.P. of 55° C.) (Moore and Munger of Shelton, Conn.). Another polymer matrix used is a one-part soft reactive silicone elastomer (GE Toshiba Silicones of Tokyo, Japan).
One unusual and unexpected property or feature of formulations of the present invention is the electrical resistivity. When Formulation 1 is formed in a pad of thickness of 3-5 mils and interposed between opposed surfaces of a semiconductor device and a heat sink, the electrical resistivity of the pad has been found to be highly significant, having a value of up to about 1012 Ω·cm (Formulation 1, Table II).
It will be appreciated that the above examples are given for purposes of illustration only and are not to be otherwise construed as a limitation upon the scope of the following appended claims.

Claims (11)

1. A method of preparing thermally conductive mechanically compliant pads comprising the steps of:
(a) selecting a quantity of an indium containing alloy which has a melt temperature of between about 40° C. and 120° C.
(b) treating said alloy to cause dispersal into divided form;
(c) combining said dispersed alloy with a compatible surface active agent and thermally conductive particles and blended to form a paste; and
(d) combining said dispersed alloy containing paste with a quantity of a flowable plastic resin material to form a thermally conductive mechanically compliant pad with said thermally conductive mechanically compliant pad comprising from between about 10% and 90% by volume of the combined dispersed metal alloy and thermally conductive particulate, balance flowable plastic resin.
2. The method of claim 1 wherein the particles making up said thermally conductive particulate solid have a diameter of between about 1 and 40 microns.
3. The method of claim 1 wherein said liquid alloy substantially encapsulates said thermally conductive particles to form a coating thereon, and wherein the liquid metal to thermally conductive particle volume ratio is at least 3:1.
4. The method of claim 1 wherein said blended paste is further blended with microwax or silicone wax to form a conformable pad, with the pad comprising between about 10% and 90% by volume of homogeneous paste, balance microwax or silicone wax.
5. The method of claim 1 being particularly characterized in that said liquid metal alloy is in liquid state at temperatures above 60° C.
6. The compliant thermally conductive pad prepared in accordance with the steps of claim 1.
7. A method of preparing thermally conductive mechanically compliant pads comprising the steps of:
(a) selecting a quantity of an indium containing alloy which has a melt temperature of between about 40° C. and 120° C.;
(b) treating said alloy to cause dispersal into divided form;
(c) combining said dispersed alloy with thermally conductive particles and blending the combination to form a paste; and
(d) combining said dispersed alloy containing paste with a quantity of a flowable plastic resin material to form a thermally conductive mechanically compliant pad with said thermally conductive mechanically compliant pad comprising between about 10 % and 90 % by volume of the combined dispersed metal alloy and thermally conductive particulate, balance flowable plastic resin.
8. A thermally conductive electrically-resistive mechanically compliant pad comprising a mixture of:
(a) between about 10 % and 90 % by volume of a paste, which paste includes a blend of:
(i) an indium containing alloy having a melt temperature of between about 40° C. and 120° C.;
(ii) thermally conductive particles, at least a portion thereof being dispersed within at least a portion of said indium containing alloy; and
(b) balance flowable plastic resin.
9. A thermally conductive electrically-resistive mechanically compliant pad comprising:
(a) an indium containing alloy having a melt temperature of between about 40° C. and 120° C., and being in divided particulate form of between about 1 and 100 μm in diameter; and
(b) a polymeric resin material having a melt temperature of between about 40° C. and 120° C.
10. A thermally conductive mechanically compliant pad as in claim 9, including a compatible surface active agent.
11. A thermally conductive mechanically compliant pad as in claim 9 wherein the melt temperature of said polymeric resin material is about 10° C. lower than the melt temperature of said indium containing alloy.
US11/122,210 2000-04-05 2005-05-04 Morphing fillers and thermal interface materials Expired - Lifetime USRE39992E1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US11/122,210 USRE39992E1 (en) 2000-04-05 2005-05-04 Morphing fillers and thermal interface materials

Applications Claiming Priority (5)

Application Number Priority Date Filing Date Title
US09/543,661 US6339120B1 (en) 2000-04-05 2000-04-05 Method of preparing thermally conductive compounds by liquid metal bridged particle clusters
US09/690,994 US6624224B1 (en) 2000-04-05 2000-10-17 Method of preparing thermally conductive compounds by liquid metal bridged particle clusters
US09/865,778 US6649325B1 (en) 2001-05-25 2001-05-25 Thermally conductive dielectric mounts for printed circuitry and semi-conductor devices and method of preparation
US09/946,879 US6797758B2 (en) 2000-04-05 2001-09-05 Morphing fillers and thermal interface materials
US11/122,210 USRE39992E1 (en) 2000-04-05 2005-05-04 Morphing fillers and thermal interface materials

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
US09/946,879 Reissue US6797758B2 (en) 2000-04-05 2001-09-05 Morphing fillers and thermal interface materials

Publications (1)

Publication Number Publication Date
USRE39992E1 true USRE39992E1 (en) 2008-01-01

Family

ID=24169008

Family Applications (3)

Application Number Title Priority Date Filing Date
US09/543,661 Expired - Lifetime US6339120B1 (en) 2000-04-05 2000-04-05 Method of preparing thermally conductive compounds by liquid metal bridged particle clusters
US09/690,994 Expired - Lifetime US6624224B1 (en) 2000-04-05 2000-10-17 Method of preparing thermally conductive compounds by liquid metal bridged particle clusters
US11/122,210 Expired - Lifetime USRE39992E1 (en) 2000-04-05 2005-05-04 Morphing fillers and thermal interface materials

Family Applications Before (2)

Application Number Title Priority Date Filing Date
US09/543,661 Expired - Lifetime US6339120B1 (en) 2000-04-05 2000-04-05 Method of preparing thermally conductive compounds by liquid metal bridged particle clusters
US09/690,994 Expired - Lifetime US6624224B1 (en) 2000-04-05 2000-10-17 Method of preparing thermally conductive compounds by liquid metal bridged particle clusters

Country Status (10)

Country Link
US (3) US6339120B1 (en)
EP (1) EP1143512B1 (en)
JP (1) JP2001329068A (en)
AT (1) ATE387722T1 (en)
CA (1) CA2343504A1 (en)
DE (3) DE1143512T1 (en)
ES (1) ES2163380T1 (en)
GR (1) GR20010300073T1 (en)
TR (1) TR200103156T3 (en)
TW (1) TW591776B (en)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10068830B2 (en) 2014-02-13 2018-09-04 Honeywell International Inc. Compressible thermal interface materials
US10155894B2 (en) 2014-07-07 2018-12-18 Honeywell International Inc. Thermal interface material with ion scavenger
US10174433B2 (en) 2013-12-05 2019-01-08 Honeywell International Inc. Stannous methanesulfonate solution with adjusted pH
US10287471B2 (en) 2014-12-05 2019-05-14 Honeywell International Inc. High performance thermal interface materials with low thermal impedance
US10312177B2 (en) 2015-11-17 2019-06-04 Honeywell International Inc. Thermal interface materials including a coloring agent
US10428256B2 (en) 2017-10-23 2019-10-01 Honeywell International Inc. Releasable thermal gel
US10501671B2 (en) 2016-07-26 2019-12-10 Honeywell International Inc. Gel-type thermal interface material
US10781349B2 (en) 2016-03-08 2020-09-22 Honeywell International Inc. Thermal interface material including crosslinker and multiple fillers
US11041103B2 (en) 2017-09-08 2021-06-22 Honeywell International Inc. Silicone-free thermal gel
US11072706B2 (en) 2018-02-15 2021-07-27 Honeywell International Inc. Gel-type thermal interface material
US11373921B2 (en) 2019-04-23 2022-06-28 Honeywell International Inc. Gel-type thermal interface material with low pre-curing viscosity and elastic properties post-curing

Families Citing this family (49)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6339120B1 (en) * 2000-04-05 2002-01-15 The Bergquist Company Method of preparing thermally conductive compounds by liquid metal bridged particle clusters
US6984685B2 (en) * 2000-04-05 2006-01-10 The Bergquist Company Thermal interface pad utilizing low melting metal with retention matrix
US6797758B2 (en) * 2000-04-05 2004-09-28 The Bergquist Company Morphing fillers and thermal interface materials
US7311967B2 (en) 2001-10-18 2007-12-25 Intel Corporation Thermal interface material and electronic assembly having such a thermal interface material
GB2395360B (en) * 2001-10-26 2005-03-16 Ngk Insulators Ltd Heat sink material
JP2003201528A (en) * 2001-10-26 2003-07-18 Ngk Insulators Ltd Heat sink material
US6946190B2 (en) * 2002-02-06 2005-09-20 Parker-Hannifin Corporation Thermal management materials
DE60229072D1 (en) * 2002-02-06 2008-11-06 Parker Hannifin Corp HEAT CONTROL MATERIALS WITH PHASE REVERSE DISPERSION
US7846778B2 (en) * 2002-02-08 2010-12-07 Intel Corporation Integrated heat spreader, heat sink or heat pipe with pre-attached phase change thermal interface material and method of making an electronic assembly
US6703128B2 (en) * 2002-02-15 2004-03-09 Delphi Technologies, Inc. Thermally-capacitive phase change encapsulant for electronic devices
US6787899B2 (en) * 2002-03-12 2004-09-07 Intel Corporation Electronic assemblies with solidified thixotropic thermal interface material
US7147367B2 (en) * 2002-06-11 2006-12-12 Saint-Gobain Performance Plastics Corporation Thermal interface material with low melting alloy
US6813153B2 (en) * 2002-09-18 2004-11-02 Intel Corporation Polymer solder hybrid
US6919504B2 (en) * 2002-12-19 2005-07-19 3M Innovative Properties Company Flexible heat sink
US6831835B2 (en) * 2002-12-24 2004-12-14 Ault, Inc. Multi-layer laminated structures, method for fabricating such structures, and power supply including such structures
US20040120129A1 (en) * 2002-12-24 2004-06-24 Louis Soto Multi-layer laminated structures for mounting electrical devices and method for fabricating such structures
US7252877B2 (en) * 2003-02-04 2007-08-07 Intel Corporation Polymer matrices for polymer solder hybrid materials
JP4551074B2 (en) * 2003-10-07 2010-09-22 信越化学工業株式会社 Curable organopolysiloxane composition and semiconductor device
US7193307B2 (en) * 2004-03-25 2007-03-20 Ault Incorporated Multi-layer FET array and method of fabricating
US20050228097A1 (en) * 2004-03-30 2005-10-13 General Electric Company Thermally conductive compositions and methods of making thereof
JP5305656B2 (en) * 2004-08-23 2013-10-02 モーメンティブ・パフォーマンス・マテリアルズ・インク Thermally conductive composition and method for producing the same
US7351360B2 (en) * 2004-11-12 2008-04-01 International Business Machines Corporation Self orienting micro plates of thermally conducting material as component in thermal paste or adhesive
US7259580B2 (en) * 2005-02-22 2007-08-21 International Business Machines Corporation Method and apparatus for temporary thermal coupling of an electronic device to a heat sink during test
CN1919962A (en) * 2005-08-26 2007-02-28 鸿富锦精密工业(深圳)有限公司 Heat interfacial material and method for making the same
CN101351755B (en) * 2006-03-28 2013-08-14 派克汉尼芬公司 Dispensable cured resin
US7527859B2 (en) * 2006-10-08 2009-05-05 Momentive Performance Materials Inc. Enhanced boron nitride composition and compositions made therewith
CN101803010B (en) * 2007-09-11 2014-01-29 陶氏康宁公司 Thermal interface material, electronic device containing the thermal interface material, and methods for their preparation and use
WO2009035906A2 (en) * 2007-09-11 2009-03-19 Dow Corning Corporation Composite, thermal interface material containing the composite, and methods for their preparation and use
WO2009131913A2 (en) * 2008-04-21 2009-10-29 Honeywell International Inc. Thermal interconnect and interface materials, methods of production and uses thereof
JP4840416B2 (en) * 2008-07-22 2011-12-21 富士通株式会社 Manufacturing method of semiconductor device
JP4913874B2 (en) * 2010-01-18 2012-04-11 信越化学工業株式会社 Curable organopolysiloxane composition and semiconductor device
US8348139B2 (en) * 2010-03-09 2013-01-08 Indium Corporation Composite solder alloy preform
JP5565758B2 (en) * 2011-06-29 2014-08-06 信越化学工業株式会社 Curable, grease-like thermally conductive silicone composition and semiconductor device
US9835648B2 (en) * 2011-06-30 2017-12-05 Intel Corporation Liquid metal interconnects
KR102429873B1 (en) * 2015-08-31 2022-08-05 삼성전자주식회사 Anisotropic conductive material, electronic device including anisotropic conductive material and method of manufacturing electronic device
WO2017044712A1 (en) 2015-09-11 2017-03-16 Laird Technologies, Inc. Devices for absorbing energy from electronic components
KR102675774B1 (en) * 2016-11-30 2024-06-18 삼성전자주식회사 Paste material, interconnection element formed from paste material and electronic device including interconnection element
DE102017116931B4 (en) 2017-07-26 2021-01-14 Deutsches Zentrum für Luft- und Raumfahrt e.V. Repair device and method of making a repair device
CN107501953B (en) * 2017-09-20 2023-03-10 深圳沃尔提莫电子材料有限公司 Heat-conducting silicone grease containing liquid metal heat-conducting filler
TWI698287B (en) 2019-08-27 2020-07-11 華碩電腦股份有限公司 Method of coating liquid metal heat-dissipatng paste and heat-dissipatng module using liquid metal heat-dissipatng paste
CN112449546B (en) * 2019-08-27 2024-07-19 华硕电脑股份有限公司 Liquid metal heat dissipation paste coating method and heat dissipation module
DE102019123950A1 (en) 2019-09-06 2021-03-11 Deutsches Zentrum für Luft- und Raumfahrt e.V. Tool device with a heating mat and repair methods and manufacturing methods for workpieces made of plastic material
DE102019123952A1 (en) 2019-09-06 2021-03-11 Deutsches Zentrum für Luft- und Raumfahrt e.V. Heating mat
CN113491584B (en) * 2020-03-20 2022-08-02 北京梦之墨科技有限公司 Liquid metal flexible patch for CT positioning and preparation method thereof
CN111589464B (en) * 2020-04-23 2023-03-31 台州学院 Boron nitride-loaded rhodium-gallium-tin liquid alloy catalyst and preparation method and application thereof
US11937372B2 (en) * 2020-06-24 2024-03-19 Yale University Biphasic material and stretchable circuit board
KR20220016680A (en) 2020-08-03 2022-02-10 삼성전자주식회사 Thermal interface material, method of manufacturing the same, and semiconductor package including the same
CN115725185B (en) * 2022-12-20 2024-03-15 深圳先进电子材料国际创新研究院 Thermal interface material based on liquid metal bridging aluminum powder and preparation method thereof
WO2024166781A1 (en) * 2023-02-09 2024-08-15 信越化学工業株式会社 Thermally conductive composition

Citations (30)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3226608A (en) 1959-06-24 1965-12-28 Gen Electric Liquid metal electrical connection
US3248615A (en) 1963-05-13 1966-04-26 Bbc Brown Boveri & Cie Semiconductor device with liquidized solder layer for compensation of expansion stresses
US3793106A (en) 1969-12-31 1974-02-19 Macdermid Inc Process for forming plastic parts having surfaces receptive to adherent coatings
US4129881A (en) 1976-03-18 1978-12-12 Ckd Praha, Oborovy Podnik Heat sink cooled, semiconductor device assembly having liquid metal interface
US4147669A (en) 1977-03-28 1979-04-03 Rockwell International Corporation Conductive adhesive for providing electrical and thermal conductivity
US4233103A (en) 1978-12-20 1980-11-11 The United States Of America As Represented By The Secretary Of The Air Force High temperature-resistant conductive adhesive and method employing same
US4254431A (en) 1979-06-20 1981-03-03 International Business Machines Corporation Restorable backbond for LSI chips using liquid metal coated dendrites
US4323914A (en) 1979-02-01 1982-04-06 International Business Machines Corporation Heat transfer structure for integrated circuit package
US4398975A (en) 1980-12-25 1983-08-16 Sony Corporation Conductive paste
US4520067A (en) 1982-06-23 1985-05-28 Union Carbide Corporation Composition useful for making circuit board substrates and electrical connectors
US4550140A (en) 1984-03-20 1985-10-29 Union Carbide Corporation Circuit board substrates prepared from poly(aryl ethers)s
US4764327A (en) 1986-01-14 1988-08-16 Mitsubishi Gas Chemical Company, Inc. Process of producing plastic-molded printed circuit boards
US5012858A (en) 1986-10-20 1991-05-07 Fujitsu Limited Method of cooling a semiconductor device with a cooling unit, using metal sherbet between the device and the cooling unit
US5053195A (en) 1989-07-19 1991-10-01 Microelectronics And Computer Technology Corp. Bonding amalgam and method of making
US5056706A (en) 1989-11-20 1991-10-15 Microelectronics And Computer Technology Corporation Liquid metal paste for thermal and electrical connections
US5170930A (en) 1991-11-14 1992-12-15 Microelectronics And Computer Technology Corporation Liquid metal paste for thermal and electrical connections
US5173256A (en) 1989-08-03 1992-12-22 International Business Machines Corporation Liquid metal matrix thermal paste
US5198189A (en) 1989-08-03 1993-03-30 International Business Machines Corporation Liquid metal matrix thermal paste
US5225157A (en) 1989-07-19 1993-07-06 Microelectronics And Computer Technology Corporation Amalgam composition for room temperature bonding
US5328087A (en) 1993-03-29 1994-07-12 Microelectronics And Computer Technology Corporation Thermally and electrically conductive adhesive material and method of bonding with same
US5445308A (en) 1993-03-29 1995-08-29 Nelson; Richard D. Thermally conductive connection with matrix material and randomly dispersed filler containing liquid metal
EP0696630A2 (en) 1994-08-10 1996-02-14 Fujitsu Limited Heat conductive material and method for producing the same
EP0708582A1 (en) 1994-10-20 1996-04-24 International Business Machines Corporation Electrically conductive paste materials and applications
US5529836A (en) 1992-07-31 1996-06-25 International Business Machines Corporation Multilayer article comprising a toughened polycyanurate
US5538789A (en) 1990-02-09 1996-07-23 Toranaga Technologies, Inc. Composite substrates for preparation of printed circuits
EP0813244A2 (en) 1996-06-14 1997-12-17 The Bergquist Company Semisolid thermal interface with low flow resistance
US5827907A (en) 1993-08-30 1998-10-27 Ibm Corporation Homo-, co- or multicomponent thermoplastic polymer dispersed in a thermoset resin
US5958590A (en) 1995-03-31 1999-09-28 International Business Machines Corporation Dendritic powder materials for high conductivity paste applications
US6339120B1 (en) * 2000-04-05 2002-01-15 The Bergquist Company Method of preparing thermally conductive compounds by liquid metal bridged particle clusters
US6649325B1 (en) 2001-05-25 2003-11-18 The Bergquist Company Thermally conductive dielectric mounts for printed circuitry and semi-conductor devices and method of preparation

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0661916B1 (en) * 1993-07-06 2000-05-17 Kabushiki Kaisha Toshiba Thermal conductivity sheet

Patent Citations (33)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3226608A (en) 1959-06-24 1965-12-28 Gen Electric Liquid metal electrical connection
US3248615A (en) 1963-05-13 1966-04-26 Bbc Brown Boveri & Cie Semiconductor device with liquidized solder layer for compensation of expansion stresses
US3793106A (en) 1969-12-31 1974-02-19 Macdermid Inc Process for forming plastic parts having surfaces receptive to adherent coatings
US4129881A (en) 1976-03-18 1978-12-12 Ckd Praha, Oborovy Podnik Heat sink cooled, semiconductor device assembly having liquid metal interface
US4147669A (en) 1977-03-28 1979-04-03 Rockwell International Corporation Conductive adhesive for providing electrical and thermal conductivity
US4233103A (en) 1978-12-20 1980-11-11 The United States Of America As Represented By The Secretary Of The Air Force High temperature-resistant conductive adhesive and method employing same
US4323914A (en) 1979-02-01 1982-04-06 International Business Machines Corporation Heat transfer structure for integrated circuit package
US4254431A (en) 1979-06-20 1981-03-03 International Business Machines Corporation Restorable backbond for LSI chips using liquid metal coated dendrites
US4398975A (en) 1980-12-25 1983-08-16 Sony Corporation Conductive paste
US4520067A (en) 1982-06-23 1985-05-28 Union Carbide Corporation Composition useful for making circuit board substrates and electrical connectors
US4550140A (en) 1984-03-20 1985-10-29 Union Carbide Corporation Circuit board substrates prepared from poly(aryl ethers)s
US4764327A (en) 1986-01-14 1988-08-16 Mitsubishi Gas Chemical Company, Inc. Process of producing plastic-molded printed circuit boards
US5012858A (en) 1986-10-20 1991-05-07 Fujitsu Limited Method of cooling a semiconductor device with a cooling unit, using metal sherbet between the device and the cooling unit
US5024264A (en) 1986-10-20 1991-06-18 Fujitsu Limited Method of cooling a semiconductor device with a cooling unit, using metal sherbet between the device and the cooling unit
US5053195A (en) 1989-07-19 1991-10-01 Microelectronics And Computer Technology Corp. Bonding amalgam and method of making
US5225157A (en) 1989-07-19 1993-07-06 Microelectronics And Computer Technology Corporation Amalgam composition for room temperature bonding
US5173256A (en) 1989-08-03 1992-12-22 International Business Machines Corporation Liquid metal matrix thermal paste
US5198189A (en) 1989-08-03 1993-03-30 International Business Machines Corporation Liquid metal matrix thermal paste
US5056706A (en) 1989-11-20 1991-10-15 Microelectronics And Computer Technology Corporation Liquid metal paste for thermal and electrical connections
US5538789A (en) 1990-02-09 1996-07-23 Toranaga Technologies, Inc. Composite substrates for preparation of printed circuits
US5565267A (en) 1990-02-09 1996-10-15 Toranaga Technologies, Inc. Composite substrates for preparation of printed circuits
US5170930A (en) 1991-11-14 1992-12-15 Microelectronics And Computer Technology Corporation Liquid metal paste for thermal and electrical connections
US5529836A (en) 1992-07-31 1996-06-25 International Business Machines Corporation Multilayer article comprising a toughened polycyanurate
US5445308A (en) 1993-03-29 1995-08-29 Nelson; Richard D. Thermally conductive connection with matrix material and randomly dispersed filler containing liquid metal
US5328087A (en) 1993-03-29 1994-07-12 Microelectronics And Computer Technology Corporation Thermally and electrically conductive adhesive material and method of bonding with same
US5827907A (en) 1993-08-30 1998-10-27 Ibm Corporation Homo-, co- or multicomponent thermoplastic polymer dispersed in a thermoset resin
EP0696630A2 (en) 1994-08-10 1996-02-14 Fujitsu Limited Heat conductive material and method for producing the same
EP0708582A1 (en) 1994-10-20 1996-04-24 International Business Machines Corporation Electrically conductive paste materials and applications
US5958590A (en) 1995-03-31 1999-09-28 International Business Machines Corporation Dendritic powder materials for high conductivity paste applications
EP0813244A2 (en) 1996-06-14 1997-12-17 The Bergquist Company Semisolid thermal interface with low flow resistance
US6339120B1 (en) * 2000-04-05 2002-01-15 The Bergquist Company Method of preparing thermally conductive compounds by liquid metal bridged particle clusters
US6624224B1 (en) * 2000-04-05 2003-09-23 The Bergquist Company Method of preparing thermally conductive compounds by liquid metal bridged particle clusters
US6649325B1 (en) 2001-05-25 2003-11-18 The Bergquist Company Thermally conductive dielectric mounts for printed circuitry and semi-conductor devices and method of preparation

Non-Patent Citations (5)

* Cited by examiner, † Cited by third party
Title
Harman Hard Gallium Alloys for Use as Low Contact Resistance Electrodes and for Bonding Thermocouples into Samples, The Review of Scientific Instruments, Jul. 1960, vol. 31, No. 7, pp. 717-720.
IBM Technical Disclosure Bulletin, vol. 19, No. 8, Jan. 1977 "Thermal Enhancement of Modules", E.B. Hultmark et al.
IBM Technical Disclosure Bulletin, vol. 20, No. 11B, Apr. 1978, "Electronic Packaging Structure", Arnold et al. pp. 4820-4822.
IBM Technical Disclosure Bulletin, vol. 20, No. 11B, Apr. 1978, "Liquid-Metal-Cooled Integrated Circuit Module Structures", Berndlmaier et al., pp. 4817-4818.
IEEE Transactions on Components, Hybrids, and Mfg. Tech., vol. 13, No. 4, Dec. 1990 "Materials/Processing Approaches to Phase Stabilization of Thermally Conductive Pastes", Anderson, Jr. et al., pp. 713-717.

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10174433B2 (en) 2013-12-05 2019-01-08 Honeywell International Inc. Stannous methanesulfonate solution with adjusted pH
US10068830B2 (en) 2014-02-13 2018-09-04 Honeywell International Inc. Compressible thermal interface materials
US10155894B2 (en) 2014-07-07 2018-12-18 Honeywell International Inc. Thermal interface material with ion scavenger
US10428257B2 (en) 2014-07-07 2019-10-01 Honeywell International Inc. Thermal interface material with ion scavenger
US10287471B2 (en) 2014-12-05 2019-05-14 Honeywell International Inc. High performance thermal interface materials with low thermal impedance
US10312177B2 (en) 2015-11-17 2019-06-04 Honeywell International Inc. Thermal interface materials including a coloring agent
US10781349B2 (en) 2016-03-08 2020-09-22 Honeywell International Inc. Thermal interface material including crosslinker and multiple fillers
US10501671B2 (en) 2016-07-26 2019-12-10 Honeywell International Inc. Gel-type thermal interface material
US11041103B2 (en) 2017-09-08 2021-06-22 Honeywell International Inc. Silicone-free thermal gel
US10428256B2 (en) 2017-10-23 2019-10-01 Honeywell International Inc. Releasable thermal gel
US11072706B2 (en) 2018-02-15 2021-07-27 Honeywell International Inc. Gel-type thermal interface material
US11373921B2 (en) 2019-04-23 2022-06-28 Honeywell International Inc. Gel-type thermal interface material with low pre-curing viscosity and elastic properties post-curing

Also Published As

Publication number Publication date
EP1143512A2 (en) 2001-10-10
TR200103156T3 (en) 2002-01-21
DE60132125D1 (en) 2008-02-14
US6339120B1 (en) 2002-01-15
ES2163380T1 (en) 2002-02-01
EP1143512A3 (en) 2004-10-06
EP1143512B1 (en) 2008-02-27
TW591776B (en) 2004-06-11
ATE387722T1 (en) 2008-03-15
DE60132943T2 (en) 2009-02-26
JP2001329068A (en) 2001-11-27
DE60132943D1 (en) 2008-04-10
DE1143512T1 (en) 2002-04-18
GR20010300073T1 (en) 2001-12-31
CA2343504A1 (en) 2001-10-05
DE60132125T2 (en) 2008-12-18
US6624224B1 (en) 2003-09-23

Similar Documents

Publication Publication Date Title
USRE39992E1 (en) Morphing fillers and thermal interface materials
US6797758B2 (en) Morphing fillers and thermal interface materials
US6984685B2 (en) Thermal interface pad utilizing low melting metal with retention matrix
JP3663032B2 (en) Semi-solid thermal interface material with low flow resistance
EP1797155B1 (en) Thermally conductive composition and method for preparing the same
US20050161632A1 (en) Phase change thermal interface composition having induced bonding property
JPH0695557B2 (en) Heat transfer compound and method for producing the same
EP0411286B1 (en) Liquid metal matrix thermal paste
CN108129841A (en) A kind of liquid metal insulating heat-conduction material and preparation method thereof
JP2009096961A (en) Heat-conductive silicone grease composition excellent in reworkability
WO2023024570A1 (en) Diamond-based thermally conductive filler and preparation method, composite thermally conductive material and electronic device
EP1143511B1 (en) Method of preparing thermally conductive compounds by liquid metal bridged particle clusters
JP2002003830A (en) Highly heat conductive composition and its application
TWI464749B (en) Conductive compositions
CA2343486A1 (en) Method of preparing thermally conductive compounds by liquid metal bridged particle clusters
US7381346B2 (en) Thermal interface material
US6652705B1 (en) Graphitic allotrope interface composition and method of fabricating the same
EP3536755A1 (en) A thermally conductive adhesive agent and a method for manufacturing thereof
JP2002020625A (en) Composition with high-heat conductivity and its use
WO2024154455A1 (en) Sheet-form heat dissipation member
WO2024101031A1 (en) Heat-conductive composition and heat-dissipating grease
WO2023250071A1 (en) Thermal interface materials with soft filler dispersions
JP2002217342A (en) Phase-change-type heat radiation member and its manufacturing method and application

Legal Events

Date Code Title Description
FPAY Fee payment

Year of fee payment: 8

AS Assignment

Owner name: THE BERGQUIST COMPANY, MINNESOTA

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:ELAHEE, GM FAZLEY;MISRA, SANJAY;REEL/FRAME:034435/0829

Effective date: 20010904

AS Assignment

Owner name: HENKEL IP & HOLDING GMBH, GERMANY

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:THE BERGQUIST COMPANY;REEL/FRAME:035779/0071

Effective date: 20150325

FPAY Fee payment

Year of fee payment: 12