TWM526265U - Heat sink with electromagnetic wave shielding - Google Patents

Description

Heat sink with electromagnetic shielding

The present invention relates to a heat sink having electromagnetic wave shielding properties, and more particularly to a heat sink having high thermal conductivity, electrical conductivity and electromagnetic wave shielding property.

At present, electronic systems are moving toward thin, short, high heat resistance, versatility, high density, high reliability, and low cost, while functionally, powerful and high-speed signal transmission is required. Therefore, the line density is bound to increase, the distance between the carrier lines is getting closer and closer, and the operating frequency is toward a high bandwidth. In addition, the electromagnetic interference (EMI) caused by the unreasonable line layout is becoming more and more serious. serious. Therefore, Electromagnetic Compatibility (EMC) must be effectively managed to maintain the normal signal transmission and improve reliability of electronic products. In addition, electronic products must have high thermal conductivity, high dimensional stability, high opacity, high heat dissipation, high heat resistance, and low thermal expansion coefficient.

In order to overcome the above drawbacks, the present invention provides a heat sink with electromagnetic wave shielding properties. The manufacturing method of the present invention is simple, and the prepared heat sink has good heat dissipation performance and good electromagnetic shielding property.

This creation provides a heat sink with electromagnetic shielding, a package And comprising: a thermally conductive ink layer, a conductive adhesive layer, and a metal layer formed between the thermally conductive ink layer and the conductive adhesive layer.

The heat shield with electromagnetic wave shielding of the present invention further comprises a release layer, and the conductive adhesive layer is formed between the metal layer and the release layer.

In one embodiment of the present invention, the thermally conductive ink layer has a thickness of from 2 to 5 microns.

In one embodiment of the present invention, the metal layer has a thickness of 5 to 105 microns.

In one embodiment of the present invention, the conductive adhesive layer has a thickness of 5 to 25 microns.

In one embodiment of the present invention, the release layer has a thickness of 25 to 50 microns.

In a specific embodiment of the present invention, the thermally conductive ink layer comprises an inorganic thermally conductive powder. Preferably, the inorganic thermally conductive powder system is selected from the group consisting of aluminum oxide, aluminum oxide, zinc oxide, boron nitride, tantalum carbide, aluminum powder, and graphene. Further, the particles of the inorganic heat conductive powder are elliptical, spherical or sheet-like.

In a specific embodiment of the present invention, the thermally conductive ink layer further comprises an inorganic pigment or an organic pigment to change the color of the thermally conductive ink layer. The thermally conductive ink layer is black, white, red, yellow or green depending on the choice of pigment. White has a reflection and lightening effect, and when the reflectance is at least 85%, it is suitable for use in an illumination lamp of an LED photoelectric product, and has an effect of increasing the brightness. Black has the effect of shielding the line and beautifying the appearance, and can be made into bright black (Gloss > 50 °) or haze black (Gloss < 20 °).

In one embodiment of the present invention, the surface of the thermally conductive ink layer is a bright color (high gloss) or a matte (small gloss) ink color. If the color of the ink to be matte is used, it may be added to the heat-conductive ink by adding at least one selected from the group consisting of calcium sulfate, cerium oxide, titanium oxide, zinc sulfide, zirconia, calcium carbonate and clay to achieve matting. The purpose is to make the thermally conductive ink layer exhibit a matte state.

In one embodiment of the present invention, the thermally conductive ink layer may comprise an inorganic pigment having a color of white, dark red, cadmium red, cadmium lemon yellow, orange cadmium yellow, or black.

In one embodiment of the present invention, the inorganic pigment may be selected from at least one of the group consisting of titanium dioxide, carbon black, and iron oxide.

In a specific embodiment of the present invention, the color of the organic pigment contained in the thermally conductive ink layer may be aniline black, enamel black, enamel black, yellow, indigo blue or indigo green. The organic pigment may be selected from at least one of the group consisting of aniline, hydrazine, hydrazine, benzidine, and indigo.

In one embodiment of the present invention, the metal layer is a copper foil, an aluminum foil or other metal alloy foil or the like.

In a specific embodiment of the present invention, the copper foil is a rolled copper foil, an electrolytic copper foil or an ultra-thin copper foil.

When the heat sink of the present invention is used for a flexible circuit board, the metal layer is preferably a rolled copper foil having a tensile strength of 500 MPa or less and a thickness of 70 μm or less, preferably a tensile strength of 350 MPa or less and a thickness of 50 Å. Calendered copper foil below micron.

In a specific embodiment of the present invention, the conductive adhesive layer comprises Conductive functional metal particles, such as metal powder. Preferably, the metal powder system is selected from the group consisting of silver powder, copper powder, aluminum powder, nickel powder, gold-coated copper powder, gold-coated nickel powder, silver-coated copper powder, silver-coated nickel powder and alloy powder. One. Further, the particles in the metal powder are spherical, elliptical or plate-like.

In a specific embodiment of the present invention, the conductive adhesive layer comprises an epoxy resin, an acrylic resin, a urethane resin, a ruthenium rubber resin, a polyparaxylene resin, and a double horse 醯At least one resin of the group consisting of an imide resin and a polyimide resin. It is preferably an acrylic resin.

In one embodiment of the present invention, the release layer is a single-sided release film or a double-sided release film, and the color is transparent or white.

The heat-shielding heat-dissipating film of the present invention is simple in manufacturing method, has excellent heat-dissipating characteristics, electromagnetic shielding effect, electrical characteristics, low thermal resistance, and also has flexibility, so that the heat sink is relatively easy to process.

1,2‧‧ ‧ heat sink structure

101‧‧‧ Thermal ink layer

102‧‧‧metal layer

103‧‧‧Electrically conductive adhesive layer

104‧‧‧ release layer

1 is a cross-sectional view showing a first embodiment of the heat sink of the present invention; and FIG. 2 is a cross-sectional view showing a second embodiment of the heat sink of the present invention.

The embodiments of the present invention are described below by way of specific embodiments, and those skilled in the art can readily appreciate other advantages and functions of the present invention from the disclosure of the present disclosure.

It should be noted that the structure, proportion and size depicted in the drawings of this specification And the like, which are used in conjunction with the disclosure of the specification for the understanding and reading of those skilled in the art, and are not intended to limit the scope of the invention, and therefore do not have any technical significance, any structural modification, The change of the proportional relationship or the adjustment of the size should not fall within the scope of the technical content disclosed in this creation without affecting the effectiveness and the purpose of the creation. In the meantime, the terms "upper", "first", "second" and "one" as used in this specification are for convenience only, and are not intended to limit the scope of the creation of the creation. Changes or adjustments in their relative relationship are considered to be within the scope of the creation of the creation of the product without substantial changes.

First embodiment

Referring to FIG. 1 , the heat sink structure 1 of the present invention includes a thermal conductive ink layer 101 , a metal layer 102 and a conductive adhesive layer 103 . The metal layer 102 is formed on the thermal conductive ink layer 101 and conductively adhered. Between layers 103.

In this embodiment, a metal layer 102 having a thickness of 5 to 105 micrometers is first provided, and a heat conductive ink is coated on any surface of the metal layer 102, and dried as needed to form a heat conductive layer having a thickness of 2 to 5 micrometers. Ink layer 101. Next, the other surface of the metal layer 102 is coated with a conductive adhesive material to form a conductive adhesive layer 103 having a thickness of 5 to 25 μm, thereby forming the heat shield having electromagnetic wave shielding properties of the present invention.

In a preferred embodiment, the thermally conductive ink layer 101 comprises an inorganic thermally conductive powder. Preferably, the inorganic thermally conductive powder system is selected from the group consisting of aluminum nitride, aluminum oxide, zinc oxide, boron nitride, tantalum carbide, aluminum powder and graphene. One of the thermal powders. The metal layer 102 is a copper foil, an aluminum foil, or another alloy foil. The conductive adhesive layer 103 comprises at least one metal selected from the group consisting of silver powder or copper powder, aluminum powder, nickel powder, gold-coated copper powder, gold-coated nickel powder, silver-coated copper powder, silver-coated nickel powder and alloy powder. Powder.

Second embodiment

Referring to FIG. 2, the heat sink structure 2 of the present invention is shown, comprising: a thermal conductive ink layer 101, a metal layer 102, a conductive adhesive layer 103 and a release layer 104, wherein the metal layer 102 is formed on the thermal conductive ink. Between the layer 101 and the conductive adhesive layer 103; the conductive adhesive layer 103 is formed between the metal layer 102 and the release layer 104.

In this embodiment, a metal layer 102 having a thickness of 5 to 105 μm is first provided, and a heat conductive ink is coated on any surface of the metal layer 102 and dried to form a thermal conductive ink layer having a thickness of 2 to 5 μm. 101. Next, a release layer 104 having a thickness of 25 to 50 μm is provided, and a conductive adhesive material is coated or transferred on any surface of the release layer 104 to form a conductive adhesive layer 103 having a thickness of 5 to 25 μm. The conductive adhesive layer 103 is in a semi-polymerized semi-hardened state (B-stage), and the other surface of the metal layer 102 is attached to the conductive adhesive layer 103 of the release layer 104, and is pressed to make it tightly adhered. The heat sink with electromagnetic wave shielding is formed.

In a preferred embodiment, the thermally conductive ink layer 101 comprises an inorganic thermally conductive powder. Preferably, the inorganic thermally conductive powder system is selected from the group consisting of thermal conductive powders of at least one group consisting of aluminum nitride, aluminum oxide, zinc oxide, boron nitride, tantalum carbide, aluminum powder and graphene, and the metal layer 102 It may be a copper foil, and the conductive adhesive layer 103 is selected from the group consisting of silver powder or copper powder, aluminum powder, nickel powder, gold-coated copper powder, gold. At least one metal powder of the group consisting of nickel-coated powder, silver-coated copper powder, silver-coated nickel powder and alloy powder, and the release layer 104 is a double-sided release film.

Embodiments 1 to 8 of the heat sink structure of the second embodiment

The heat sink structure of the second embodiment of the present invention is manufactured by the method described below in accordance with the materials and thicknesses described in Table 1.

First, a copper foil layer is provided, and a heat conductive ink is applied to any surface of the copper foil layer and dried to form a thermally conductive ink layer. Next, a double-sided release layer is provided, and a conductive adhesive material is coated or transferred on any surface of the double-sided release layer to form a conductive adhesive layer, and the conductive adhesive layer is in a semi-polymerized semi-hardened state (B- Stage), the other surface of the copper foil layer is attached to the conductive adhesive layer of the double-sided release layer, and is pressed and bonded tightly, thereby forming the heat dissipation of the second embodiment of the present invention. sheet.

Comparative Example 1 Heat sink structure without a thermally conductive ink layer

A copper foil layer is provided, and an adhesive material is applied to the rough surface of the copper foil layer and dried to form a semi-cured adhesive layer. Next, a single-sided release layer is provided to adhere the adhesive layer. At this time, the adhesive layer is in a semi-polymerized semi-hardened state (B-stage), that is, the heat sink of Comparative Example 1 is formed.

Comparative Example 2 Heat sink structure without a thermally conductive ink layer

A copper foil layer is provided, and a conductive adhesive layer is coated on the rough surface of the copper foil layer and dried to form a semi-cured conductive adhesive layer. Next, a single-sided release layer is provided to adhere the adhesive layer, and the adhesive layer is in a semi-polymerized semi-hardened state (B-stage), that is, the heat sink of Comparative Example 2 is formed.

Test example: Characteristic test of the heat sink structure of this creation

After the double-sided release film of the heat sink structure samples of Examples 1 to 8 was peeled off, heat conduction and conductivity were performed with the heat sink structure samples of Comparative Examples 1 and 2. Sex and electromagnetic wave shielding test.

Thermal conductivity: Thermal conductivity is tested using a Hot Disk thermal conductivity meter. Two fully cured fin samples are placed on the upper and lower sides of the sensor, and the sample and sensor are sandwiched by two steel plates on the outer sides of the two samples. The thermal conductivity of the heat sink was measured by a sensor, and the results are reported in Table 2.

Conductivity: The copper foil single-plate substrate is etched to form a sample having a strip line, and then a cover film after punching is additionally prepared and attached to the strip line of the sample, at which time the hole exposes the strip line, and finally The heat sink was thermocompression bonded to the top of the cover film, and the electrical resistance (Ω) was measured using a multi-function high-precision electric meter (model CIE 3130B) to measure the conductivity data.

Electromagnetic wave shielding: First, the heat sink (the shielding material to be tested) is made into two samples, one is a load specimen and the other is a reference specimen. The load sample was a solid circle having a diameter of 133 mm, and the reference sample was a circular pattern having a diameter of 33 mm and a ring pattern of 133 (outer diameter) / 76 (inner diameter) mm. The coaxial transmission line tester and line analyzer using the model of Wiltron 37225B were measured by the coaxial transmission line method (ASTM 4935), and finally the electromagnetic wave shielding data of the heat sink was obtained.

Referring to Table 2, the heat sinks of the present inventions of Examples 1 to 8 can greatly improve the heat dissipation effect of the materials compared to Comparative Examples 1 and 2, and at the same time have good electrical conductivity and electromagnetic wave shielding properties.

The above embodiments are intended to illustrate the principles of the present invention and its effects, and are not intended to limit the present invention. Anyone who is familiar with the art may modify the above embodiments without departing from the spirit and scope of the creation. Therefore, the scope of protection of this creation should be as listed in the scope of patent application described later.

1‧‧ ‧ heat sink structure

101‧‧‧ Thermal ink layer

102‧‧‧metal layer

103‧‧‧Electrically conductive adhesive layer

Claims (19)

A heat sink with electromagnetic wave shielding includes: a thermally conductive ink layer; a conductive adhesive layer; and a metal layer formed between the thermally conductive ink layer and the conductive adhesive layer. The heat sink according to claim 1, further comprising a release layer disposed on the conductive adhesive layer, wherein the conductive adhesive layer is formed between the metal layer and the release layer. The heat sink of claim 1, wherein the thermally conductive ink layer has a thickness of 2 to 5 μm. The heat sink of claim 1, wherein the metal layer has a thickness of 5 to 105 μm. The heat sink of claim 1, wherein the conductive adhesive layer has a thickness of 5 to 25 μm. The heat sink of claim 2, wherein the release layer has a thickness of 25 to 50 microns. The heat sink of claim 1, wherein the thermally conductive ink layer comprises at least a group selected from the group consisting of aluminum nitride, aluminum oxide, zinc oxide, boron nitride, tantalum carbide, aluminum powder, and graphene. One of the thermal powders. The heat sink of claim 1, wherein the surface of the thermally conductive ink layer is a glossy or matte surface. The heat sink of claim 1, wherein the thermally conductive ink layer comprises an inorganic pigment or an organic pigment. The heat sink according to claim 9, wherein the inorganic pigment is at least one selected from the group consisting of titanium dioxide, carbon black, and iron oxide. The heat sink according to claim 9, wherein the organic pigment is at least one selected from the group consisting of aniline, anthraquinone, anthracene, benzidine and indigo. The heat sink of claim 8, wherein the matte thermal conductive ink layer comprises at least a group selected from the group consisting of calcium sulfate, cerium oxide, titanium dioxide, zinc sulfide, zirconium oxide, calcium carbonate, and clay. One of the additions. The heat sink according to claim 1, wherein the metal layer is a copper foil, an aluminum foil or an alloy foil. The heat sink of claim 1, wherein the metal layer is a copper foil. The heat sink according to claim 14, wherein the copper foil has a tensile strength of 500 MPa or less and a thickness of 70 μm or less. The heat sink of claim 1, wherein the conductive adhesive layer comprises a metal powder. The heat sink according to claim 16, wherein the metal powder system is selected from the group consisting of silver powder, copper powder, nickel powder, aluminum powder, graphite powder, nickel-plated graphite powder, gold-coated copper powder, gold-coated nickel powder, At least one of the group consisting of silver-coated copper powder, silver-coated nickel powder, and alloy powder. The heat sink according to claim 16, wherein the particles of the metal powder are spherical, elliptical or sheet-shaped. The heat sink according to claim 1, wherein the conductive adhesive layer comprises an epoxy resin, an acrylic resin, an urethane resin, a ruthenium rubber resin, and a polyparaxylene resin. At least one resin of the group consisting of a bismaleimide resin and a polyamidene resin.