Electromagnetic interference (EMI) mitigation materials and EMI absorbing compositions including carbon nanotubes

Abstract

Exemplary embodiments of electromagnetic interference (EMI) mitigation materials and EMI absorbing compositions that include carbon nanotubes are disclosed. The carbon nanotubes may include single-walled carbon nanotubes, multi-walled carbon nanotubes, and / or carbon nanostructures comprising a branched network of cross-linked carbon nanotube structures. For example, exemplary embodiments may include a composition including carbon nanotubes in a polymer resin, whereby the composition is operable to absorb noise and / or to reflect signals, thereby preventing passage or transmission of signals through the composition. Further, for example, exemplary embodiments may include a broadband millimeter wave EMI absorber comprising carbon nanotubes.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of U.S. Patent Application No. 17 / 962,698, filed on October 10, 2022, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present disclosure relates to electromagnetic interference (EMI) mitigation materials and EMI absorbing compositions including carbon nanotubes (eg, single-walled carbon nanotubes, multi-walled carbon nanotubes, and / or carbon nanostructures, etc.). Background Art

[0004] This section provides background information related to the present disclosure which is not necessarily prior art.

[0005] Electrical components such as semiconductors, integrated circuit packages, transistors, etc. typically have pre-designed temperatures at which the electrical components operate optimally. Ideally, the pre-designed temperature is close to the temperature of the surrounding air. However, the operation of the electrical components generates heat. If the heat is not removed, the electrical components may operate at a temperature significantly higher than their normal or desirable operating temperature. Such excessively high temperatures may adversely affect the operating characteristics of the electrical components and the operation of the associated devices.

[0006] In order to avoid or at least reduce the adverse operating characteristics from heat generation, heat should be removed, for example, by conducting the heat from the operating electrical components to the heat sink. The heat sink can then be cooled by conventional convection and / or radiation techniques. During conduction, heat can be transferred from the operating electrical components to the heat sink by direct surface contact between the electrical components and the heat sink and / or by contact of the electrical components and the heat sink surfaces via an intermediate medium or thermal interface material (TIM). Thermal interface materials can be used to fill the gaps between the heat transfer surfaces in order to increase the heat transfer efficiency compared to filling the gaps with air (a relatively poor thermal conductor).

[0007] In addition, a common problem in the operation of electronic devices is the generation of electromagnetic radiation within the electronic circuits of the device. This radiation can cause electromagnetic interference (EMI) or radio frequency interference (RFI), which can interfere with the operation of other electronic devices within a certain distance. Without adequate shielding, EMI / RFI interference can cause degradation or complete loss of important signals, rendering the electronic device inefficient or inoperable.

[0008] A common solution to mitigate the effects of EMI / RFI is through the use of shields that can absorb and / or reflect and / or redirect EMI energy. These shields are typically employed to keep the EMI / RFI within its source and isolate other devices adjacent to the EMI / RFI source.

[0009] As used herein, the term "EMI" should be considered to include and refer generally to EMI emissions and RFI emissions, and the term "electromagnetic" should be considered to include and refer generally to electromagnetic frequencies and radio frequencies from external and internal sources. Thus, the term shielding (as used herein) broadly includes and refers to mitigating (or limiting) EMI and / or RFI, such as by absorbing, reflecting, blocking and / or redirecting energy, or some combination thereof, so that EMI and / or RFI no longer interferes, for example, with government compliance and / or internal functions of electronic component systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.

[0011] Figures 1A to 1E An exemplary pyramid pattern of a material according to an exemplary embodiment is shown.

[0012] FIG. 2A to FIG. 2E Steps of an exemplary process related to fabricating a pattern in a filled dielectric system according to an exemplary embodiment are respectively shown.

[0013] Figure 3 A multilayer film structure including a block copolymer film having a through-thickness domain according to an exemplary embodiment is shown.

[0014] Figure 4 A multilayer film structure is shown in which the filler density of each layer increases in a direction from the top layer to the bottom layer according to an exemplary embodiment.

[0015] Figure 5 A filled dielectric having a pyramid structure is shown according to an exemplary embodiment, wherein the pyramid structure includes air-filled micro-balloons, micro-spheres or micro-bubbles therein.

[0016] Figure 6 An exemplary embodiment including a pyramid structure, a planarization layer, and a multi-layer frequency selective surface (FSS) structure is shown.

[0017] Figure 7 A pyramid structure is shown along a portion of a board level shield (BLS) according to an exemplary embodiment.

[0018] Figure 8 Pyramid structures along a portion of a BLS are shown according to an exemplary embodiment, wherein one or more of the pyramid structures have different dimensions (eg, different randomized or non-randomized heights, etc.) than one or more other pyramid structures.

[0019] Fig. 9A pyramid structure along a portion of a BLS is shown according to an exemplary embodiment, wherein air-filled micro-balloons, micro-spheres, or micro-bubbles are included in the pyramid structure, for example, to reduce the dielectric constant of the pyramid structure.

[0020] Fig.10 Pyramid structures along a portion of a BLS are shown according to an exemplary embodiment, wherein at least one or more of the pyramid structures are multi-layered and the packing density of each layer increases in a direction from a top layer to a bottom layer.

[0021] Fig.11 A BLS according to an exemplary embodiment and pyramidal structures along the inner surfaces of the top and side walls of the BLS are shown, wherein the pyramidal structures protrude inward from the top and side walls of the BLS in a direction generally toward a component on a substrate (e.g., an integrated circuit (IC) on a printed circuit board (PCB), etc.).

[0022] Fig.12 A BLS is shown according to an exemplary embodiment along with pyramid structures along the outer surfaces of the BLS top and sidewalls, wherein the pyramid structures protrude outwardly from the BLS top and sidewalls in a direction generally away from the PCB components.

[0023] Fig.13 A BLS and pyramidal structures along the top and side walls of the BLS are shown according to an exemplary embodiment, wherein the pyramidal structures are along both the outer and inner surfaces of the BLS top and side walls that protrude outward and inward in opposite directions generally toward and generally away from the PCB component, respectively.

[0024] Fig.14 Both non-pyramid structures and pyramidal structures are shown along a portion of a BLS according to an exemplary embodiment.

[0025] Fig.15 A non-pyramid structure along a portion of a BLS is shown according to an exemplary embodiment.

[0026] Fig.16 An outer device housing is shown according to an exemplary embodiment, which includes multi-layer films and / or metamaterials configured to provide one or more of an electrical conductor, a waveguide, an EMI absorber, a thermal interface material (TIM), and a dielectric.

[0027] Fig.17 An interposer between two PCBs is shown according to an exemplary embodiment, comprising multilayer films and / or metamaterials configured to provide one or more of an electrical conductor, a waveguide, an EMI absorber, a thermal interface material (TIM), and a dielectric.

[0028] Fig.18An integrated circuit (IC) package is shown according to an exemplary embodiment, which includes multilayer films and / or metamaterials configured to provide one or more of electrical conductors / interconnects, waveguides, EMI absorbers, thermal interface materials (TIMs), and dielectrics.

[0029] Fig.19 A multi-layered frequency selective surface (FSS) structure including patterns of conductive, EMI absorbing and / or metamaterial elements is shown according to an exemplary embodiment.

[0030] Fig. 20 A metamaterial TIM configured and operable to provide a thermally conductive heat path and to direct a millimeter wave signal generally toward a reflector is shown according to an exemplary embodiment.

[0031] Fig.21A and Fig. 21B According to an exemplary embodiment, the FIG. 2A to FIG. 2E Example flexible material filled dielectric pyramid structures made by the process shown.

[0032] Fig. 22 is a perspective view of a board level shield (BLS) having one sidewall of the BLS made of EMI absorbing material or absorber according to an exemplary embodiment.

[0033] Fig.23 It is shown Fig. 22 Graphs of simulated reduction in total radiated power (decibels (dB)) versus frequency (gigahertz (GHz)) for a board level shield in FIG. 5 , where the position of the absorber is varied in two cases as the frequency shift of maximum total radiated power reduction occurs.

[0034] Fig.24 EMI absorbing pyramid structures are shown along the exterior of a device component defining a cavity or chamber according to an exemplary embodiment.

[0035] Fig.25 A pyramid structure of an EMI absorber according to an exemplary embodiment is shown.

[0036] Fig.26 is a graph of reflection loss (decibel (dB)) versus frequency (gigahertz (GHz)) for a composition including 0.5 volume % (vol%) carbon nanostructures. For comparison, Fig.26 Also included are reflection losses for a composition including 10 vol% carbon black and a composition including 50 vol% silicon carbide (SiC).

[0037] Corresponding reference numerals may indicate corresponding (but not necessarily identical) parts throughout the several views of the drawings. DETAILED DESCRIPTION

[0038] Example embodiments will now be described more fully with reference to the accompanying drawings.

[0039] As recognized herein, systems that transmit energy may experience interference from reflections back to the transmitter. These unwanted reflections may interfere with other systems. EMI absorbers with magnetic or dielectric fillers may be used to reduce the level of reflections. Typical reflectivity reduction for weather-resistant outdoor EMI absorber materials may be -20 decibels (dB), which will eliminate about 99% of reflections. Conventional broadband millimeter wave EMI absorbers with frequencies of 77 gigahertz (GHz) and 90 GHz may include dielectric fillers such as carbon black and / or silicon carbide with very high loadings of up to 20 volume % (vol %) to achieve -20 dB reflection losses. However, manufacturing with such high filler loadings is often difficult, especially when manufacturing EMI absorbing sheets with relatively fine pyramidal patterns.

[0040] Thus, exemplary embodiments of EMI mitigation materials (e.g., EMI absorbers, thermally conductive EMI absorbers, etc.) comprising carbon nanotubes are disclosed herein. The carbon nanotubes may include single-walled carbon nanotubes, multi-walled carbon nanotubes, and / or carbon nanostructures comprising a branched network of cross-linked carbon nanotube structures. For example, exemplary embodiments may include broadband millimeter-wave EMI absorbers comprising carbon nanotubes.

[0041] Exemplary embodiments may include relatively low filler loadings (e.g., as low as 0.1% to 0.5% by volume) of carbon nanostructures (CNS) and other highly conductive coatings, branched and cross-linked carbon nanotube structures, etc. At such low filler loading levels, the CNS filler can be fully mixed in a liquid silicone or other thermosetting material matrix to give a low viscosity. The low viscosity mixture can allow the mixture to be easily poured or cast into a shape or pattern (e.g., a pattern of pyramidal structures, etc.) that can be configured to operate at a frequency of about 40 gigahertz (GHz) to about 120 GHz and / or a frequency of about 60 GHz to about 90 GHz and / or a frequency of about 70 GHz to about 85 GHz with a reflection loss greater than 15 decibels (e.g., a reflection loss greater than 20 dB, etc.).

[0042] In an exemplary embodiment, the CNS material is mixed in a liquid silicone or a thermosetting material at a low concentration ranging from about 0.1 vol% to about 1.0 vol%, for example, by using a centrifugal mixer, etc. The composition or mixture is low in viscosity and can be easily poured or cast into a mold to make a mold such as Fig.26The compositions shown to have high loadings of carbon black (e.g., 10 vol%, etc.) or silicon carbide (SiC) (e.g., 50 vol%, etc.) produce similar or better results than pyramid pattern parts. Advantageously, in some exemplary embodiments, low filler loading levels of CNS (e.g., about 0.1 vol% to about 1.0 vol%, etc.) produce low viscosities for easier manufacturing and lower costs than higher filler loading levels.

[0043] In an exemplary embodiment, the EMI absorber includes carbon nanotubes within a polymer resin. The EMI absorber is operable to absorb noise and / or to reflect signals, thereby preventing the signals from passing or transmitting through the EMI absorber.

[0044] In an exemplary embodiment, an automotive component (e.g., a radar bracket, etc.) includes an EMI absorber that includes carbon black and / or carbon nanotubes in an injection moldable resin and / or is configured to operate at a frequency of about 40 gigahertz (GHz) to about 120 GHz and / or a frequency of about 60 GHz to about 90 GHz and / or a frequency of about 70 GHz to about 85 GHz with a reflection loss greater than 15 decibels. The EMI absorber is operable to absorb noise and / or to reflect signals, thereby preventing the signals from passing or transmitting through the automotive component.

[0045] In an exemplary embodiment, the composition of the injection moldable EMI absorber includes carbon black and / or carbon nanotubes within an injection moldable resin. The composition is operable to absorb noise and / or to reflect signals, thereby preventing the signals from passing or transmitting through the composition.

[0046] In an exemplary embodiment, the composition of the EMI absorber includes carbon nanotubes in a polymer resin. The composition is operable to absorb noise and / or to reflect signals, thereby preventing the signal from passing or transmitting through the composition. The carbon nanotubes may include one or more of single-walled carbon nanotubes, multi-walled carbon nanotubes, and / or carbon nanostructures including a branched network of cross-linked carbon nanotube structures.

[0047] The resin may include a thermoplastic resin. The carbon nanotube may include a single-walled carbon nanotube in a thermoplastic resin, a multi-walled carbon nanotube in a thermoplastic resin, and / or a carbon nanostructure of a branched network including a cross-linked carbon nanotube structure in a thermoplastic resin. The thermoplastic resin may include one or more of liquid silicone, urethane, polycarbonate, polyamide, polyester, and / or polyolefin. In some exemplary embodiments, the thermoplastic resin includes one or more of polybutylene terephthalate, polypropylene, thermoplastic vulcanizate, thermoplastic elastomer, and / or a mixture including polyolefin.

[0048] The resin may include an injection moldable resin. The carbon nanotubes may include single walled carbon nanotubes within the injection moldable resin, multi walled carbon nanotubes within the injection moldable resin, and / or a carbon nanostructure including a branched network of cross-linked carbon nanotube structures within the injection moldable resin.

[0049] The resin may include polypropylene and Santoprene thermoplastic vulcanizate, and the carbon nanotubes may include carbon nanostructures. For example, exemplary embodiments (e.g., compositions, EMI absorbers, automotive parts, etc.) may include about 29.5% by volume or less of Santoprene thermoplastic vulcanizate, about 69.5% by volume or more of polypropylene, and about 0.5% by volume or less of carbon nanostructures. As another example, exemplary embodiments (e.g., compositions, EMI absorbers, automotive parts, etc.) may include about 10% by volume or less of Santoprene thermoplastic vulcanizate, about 89% by volume or more of polypropylene, and about 0.3% by volume or less of carbon nanostructures.

[0050] The resin may include a two-component silicone composition including a silicone component A and a silicone component B. The ratio of the weight percentage of the silicone component A to the weight percentage of the silicone component B may be in the range of about 1:1 to about 10:1.

[0051] The resin may include a two-component urethane composition including a urethane component A and a urethane component B. The ratio of the weight percent of urethane component A to the weight percent of urethane component B may be in a range of about 1:1 to about 10:1.

[0052] The resin may include a silicone or urethane resin. Example embodiments (eg, a composition, an EMI absorber, an automotive component, etc.) may include about 99.4 wt % silicone or urethane resin and about 0.6 wt % carbon nanotubes in the silicone or urethane resin.

[0053] Exemplary embodiments (e.g., compositions, EMI absorbers, automotive parts, etc.) may include about 98 to about 99 weight percent resin and about 2 weight percent or less carbon nanotubes. Exemplary embodiments (e.g., compositions, EMI absorbers, automotive parts, etc.) may include about 1 volume percent or less carbon nanotubes.

[0054] Exemplary embodiments (e.g., compositions, EMI absorbers, automotive parts, etc.) may be configured to operate with a reflection loss greater than 15 decibels at frequencies from about 40 gigahertz (GHz) to about 120 GHz and / or from about 60 GHz to about 90 GHz and / or from about 70 GHz to about 85 GHz.

[0055] Exemplary embodiments (eg, compositions, EMI absorbers, automotive parts, etc.) can include about 0.5 volume percent or less of carbon nanotubes.

[0056] Exemplary embodiments (eg, compositions, EMI absorbers, automotive components, etc.) may be configured to operate at frequencies of approximately 77 GHz with reflection losses greater than 15 decibels.

[0057] In an exemplary embodiment (e.g., a composition, an EMI absorber, an automotive component, etc.), one or more fillers and / or additives are within the resin. The one or more fillers and / or additives may include one or more pigments, plasticizers, processing aids, flame retardants, extenders, tackifiers, EMI absorbing fillers, conductive fillers, and / or magnetic particles.

[0058] EMI absorbers (e.g., EMI absorbing sheets, automotive parts, injection molded EMI absorbers, EMI absorbing automotive parts, EMI absorbing radar brackets, etc.) may include the compositions disclosed herein and / or be made (e.g., injection molded, etc.) from the compositions disclosed herein. For example, the EMI absorber may be injection molded from the composition so that the EMI absorber has an integral, one-piece construction. As another example, the EMI absorber may be an EMI absorbing sheet made from the composition.

[0059] The EMI absorber may include a pattern of EMI absorbing structures comprising the composition. The EMI absorbing structure may include a quadrangular pyramid structure including a rectangular base configured so that the rectangular bases of adjacent quadrangular pyramid structures are in contact with each other without substantially any gap or spacing distance between the rectangular bases of adjacent quadrangular pyramid structures. The pattern of the EMI absorbing structure may include a pattern of pyramidal structures, a pattern of non-pyramidal structures, a pattern including a combination of pyramidal structures and non-pyramidal structures, and / or a pattern including a structure of at least two structures with predetermined or random different heights. The EMI absorbing structure may protrude outwardly along a first portion of the EMI absorber. The fabric may be along a second portion of the EMI absorber opposite to the first portion along which the EMI absorbing structure protrudes outwardly. The fabric may include one or more of a flame retardant meta-aromatic polyamide material and / or an open woven polymer fabric; and / or the fabric may include a fabric layer along the second portion of the EMI absorber; and / or the fabric may be configured to provide reinforcement and mechanical strength to the EMI absorber.

[0060] The radar bracket can be injection molded from the composition disclosed herein. The EMI absorbing radar bracket can include the composition disclosed herein and / or be made of the composition disclosed herein (e.g., injection molding, etc.). The EMI absorbing radar bracket can be configured to be positionable relative to the radar device, where the reflection loss changes the radiation around the radar device. The radar bracket may include a pattern of EMI absorbing structures, which include the composition disclosed herein and / or are made of the composition disclosed herein (e.g., injection molding, etc.). The EMI absorbing structure may protrude outward along at least a portion of the radar bracket. The automotive component may include the composition disclosed herein and / or be made of the composition disclosed herein (e.g., injection molding, etc.). The automobile may include the automotive component and / or the radar bracket disclosed herein.

[0061] Thermal management and EMI mitigation materials may include the compositions disclosed herein. Thermal management and EMI mitigation materials may be configured to be multifunctional, having a first function of EMI mitigation and a second function of thermal management. For example, thermal management and EMI mitigation materials may be configured to operate at frequencies of about 40 gigahertz (GHz) to about 120 GHz with a reflection loss greater than 15 decibels and have a high thermal conductivity (e.g., in a range of about 1 W / mK (watts per meter per Kelvin) to about 10 W / mK, etc.).

[0062] EMI mitigation materials may include the compositions disclosed herein. For example, the EMI mitigation material may include a multilayer film structure defined by multiple layers having different filler densities and / or concentrations. As another example, EMI mitigation may include a multilayer film structure defined by multiple layers including fillers dispersed within the layers to define through-thickness domains and / or separated discrete regions within the layers.

[0063] In an exemplary embodiment, a method for preparing a composition for an EMI absorber includes: mixing carbon nanotubes in a polymer resin so that the composition includes less than 1% by volume of carbon nanotubes. The composition can be operated to absorb noise and / or to reflect signals, thereby preventing signals from passing through the composition or transmitting. For example, the composition can be operated at a frequency of about 40 gigahertz (GHz) to about 120GHz and / or a frequency of about 60GHz to about 90GHz and / or a frequency of about 70GHz to about 85GHz with a reflection loss greater than 15 decibels. The composition can be operated at a frequency of about 77GHz with a reflection loss greater than 15 decibels. The composition can be configured to be multifunctional, having a first function of EMI mitigation and a second function of thermal management. For example, the composition can be configured to operate at a frequency of about 40 gigahertz (GHz) to about 120GHz with a reflection loss greater than 15 decibels, and having a high thermal conductivity (e.g., in the range of about 1W / mK (watt / meter / calvin) to about 10W / mK, etc.). The composition may include about 0.5% by volume or less of carbon nanotubes. The carbon nanotubes may include single-walled carbon nanotubes, multi-walled carbon nanotubes, and / or carbon nanostructures including a branched network of cross-linked carbon nanotube structures. The polymer resin may include a liquid silicone and / or a thermosetting material matrix.

[0064] The method may include mixing carbon nanotubes into a composite liquid silicone and / or thermoset matrix such that the composition includes carbon nanotubes in an amount ranging from about 0.1 volume % to about 0.5 volume %.

[0065] The method may include pouring or casting the composition into a mold, and molding the composition into a molded part having a pattern of an EMI absorber. The EMI absorber may include a quadrangular pyramid structure protruding outward along at least one side of the molded part and including a rectangular base, which is configured such that the rectangular bases of adjacent quadrangular pyramid structures contact each other without substantially any gap or spacing distance between the rectangular bases of adjacent quadrangular pyramid structures. Molding the composition into a molded part may include injection molding the composition into a radar bracket.

[0066] Also disclosed herein are exemplary embodiments of films (e.g., multilayer block copolymer films, homogeneous block copolymer films, monolayer block copolymer films, etc.) and patterned materials (e.g., roll-to-roll patternable polymers, etc.) that may have controlled and / or tailored properties (e.g., thermal management, electromagnetic interference (EMI) mitigation, electrical conductivity, thermal conductivity, EMI absorption, magnetic, dielectric and / or structural properties, etc.). Also disclosed are exemplary embodiments of systems and methods for preparing such multilayer films, patterned materials, and monolayer / homogeneous films. Also disclosed are exemplary embodiments of thermal management and / or EMI mitigation materials, board-level shields, and devices. For example, an electronic device (e.g., a smart phone, a smart watch, a 5G package antenna (AIP), etc.) may include one or more of the multilayer films, patterned materials, monolayer / homogeneous films, board-level shields, and / or thermal management and / or EMI mitigation materials disclosed herein.

[0067] In an exemplary embodiment, the material includes a pattern of structures (e.g., a pattern of pyramidal structures, a hierarchical pattern, a pattern of non-pyramidal structures, a pattern of bell-shaped structures, a combination thereof, etc.). The material may include a filled dielectric, such as polydimethylsiloxane filled with carbon black and / or carbon nanotubes (e.g., single-walled carbon nanotubes, multi-walled carbon nanotubes and / or carbon nanostructures, etc.), a filled block copolymer system, a filled elastic system (e.g., cured elastomer, thermoplastic elastomer (TPE), Santoprene thermoplastic vulcanizate, etc.), a filled thermoplastic system (e.g., liquid silicone, urethane, polycarbonate, polyamide, polyester, polyolefin, polybutylene terephthalate, thermoplastic vulcanizate, thermoplastic elastomer, a mixture including polyolefin, acrylonitrile butadiene styrene (ABS), polypropylene (PP), polyethylene (PE), etc.), an injection moldable and / or polymer resin filled with single-walled carbon nanotubes, multi-walled carbon nanotubes and / or carbon nanostructures, etc. The structural pattern may include a pattern of pyramidal structures (e.g., a quadrangular pyramid, a truncated pyramid with a rectangular base, Figures 1A to 1E The pyramidal structure shown, etc.), a non-pyramid structure, or a combination of a pyramidal structure and a non-pyramid structure.

[0068] Referring now to the accompanying drawings, Figures 1A to 1E An exemplary pyramid pattern 100 for a material (eg, a film, a layer, etc.) is shown in accordance with an exemplary embodiment. Example dimensions (in centimeters (cm)) are provided for illustration purposes only. Other exemplary embodiments may include Figures 1A to 1E The different patterns shown, for example, patterns of non-pyramid structures, structures with different sizes, structures with different patterns or layouts, combinations of pyramidal structures and non-pyramid structures, etc.

[0069] FIG. 2A to FIG. 2E1 and 2 respectively show methods for making patterns (e.g., in a filled dielectric system (e.g., polydimethylsiloxane (PDMS) filled with carbon black and / or carbon nanotubes, a filled block copolymer system, a filled elastic system, a filled thermoplastic system, an injection moldable resin filled with carbon nanotubes, a polymer resin filled with carbon nanotubes, etc.) according to exemplary embodiments. Figures 1A to 1E In general, the exemplary process includes computer design to model a part, 3D printing or additive manufacturing to create a modeled part, finishing the 3D printed part for final properties (e.g., gloss, etc.), creating a mold using the 3D printed part, and creating a material including the pattern in a filled dielectric system using the mold (e.g., via casting, injection molding, etc.).

[0070] First step 201 ( Figure 2A ) includes computer design to model the part. Computer modeling of the 3D part, for example by using computer-aided design (CAD) or the like. The second step 202 ( Figure 2B ) includes 3D printing or additive manufacturing (e.g., fused deposition modeling (FDM), stereolithography (SLA), laser direct structure (LDS), etc.) of the modeled part based on information from the computer design of the modeled part. The 3D printed part (e.g., 3D printed thermoplastic relief master, etc.) can then undergo post-processing, such as removing excess material, post-curing, applying a surface layer for matte or glossy finishing, etc.

[0071] The third step 203 ( Figure 2C ) includes using 3D printed parts to replicate molds (e.g., elastomers, etc.). For example, a pattern can be replicated into a concave mold using a 3D printed part in various ways. For example, a pattern can be replicated into a concave mold made of polydimethylsiloxane (PDMS) via fused deposition modeling, stereolithography, etc. using a 3D printed part. The concave mold can be surface treated, such as with a release layer (e.g., a self-assembled monolayer, other barrier or release layer, etc.) for easy demolding, ultraviolet (UV) vitrification, vapor phase silanization, etc.

[0072] As another example, frontal photopolymerization and a polymerizable photoresist can be used to create a concave PDMS mold, for example, from a rigid thiol-ene pattern, etc. As another example, CNC (computer numerical control) milling can be used to create a metal (e.g., aluminum, etc.) concave mold. Another example includes a frontal photopolymerization method using thiol-ene as an optical adhesive that is cured under a UV lamp while on a conveyor belt in a continuous process (e.g., configured to pass under the UV lamp several times during curing, etc.). Additional examples include replicating a pattern into a thermoset material to provide a mold from which a part (e.g., a thermoset material, a thermoplastic material, an elastomer, etc.) can be further replicated.

[0073] Fourth step 204 ( Figure 2D ) includes using a concave mold to create a part made of PDMS and carbon black. For example, this fourth step 204 can be performed after making a reverse PDMS mold (concave pattern) from a 3D printed master (convex pattern). In this fourth step 204, the concave mold is used as a starting point for making a pattern (e.g., a pyramid pattern, other geometric patterns, etc.) in a filled dielectric (e.g., PDMS filled with carbon black, an injection moldable resin filled with carbon nanotubes, a polymer resin filled with carbon nanotubes, etc.). The mixture of PDMS and carbon black (or other filled dielectric system) can be applied (e.g., poured, etc.) to the concave mold, then degassed and oven cured, and then the PDMS / carbon black part is removed (e.g., peeled off, etc.) from the concave mold.

[0074] Fifth step 205 ( Figure 2E ) can include testing the molded PDMS and carbon black parts. For example, the height and width of the pattern produced on the molded part can be analyzed. Or, for example, the molded part can undergo a reflectivity test. As another example, the concave PDMS mold can undergo a durability test to determine how many molded parts can be created using a single mold (e.g., at least 20 filled elastomer parts, etc.) before the height and pattern fidelity begin to deteriorate after casting multiple parts from a single mold.

[0075] In alternative exemplary embodiments, other processes may alternatively or additionally be used to prepare patterned materials in a filled dielectric system. Example processes include roll-to-roll processes, such as a roll-to-roll patternable polymer process for continuous pattern replication, a roll-to-roll process including multiple nozzles for dispensing materials onto a film or layer simultaneously, and the like. Other example processes include extrusion, curtain coating, 3D printing or additive manufacturing (e.g., fused deposition modeling, stereolithography, laser direct construction with modeling, etc.), front photopolymerization with a photomask and / or with a soft master, CNC (computer numerical control) milling, injection or compression molding (e.g., using thermoset molds, etc.), soft molding (e.g., using pre-formed (cross-linked) PDMS molds, etc.), UV systems with conveyor belt thermoplastic replication, thermoset masters, thiol-ene with soft masters, inkjet (e.g., inkjet dielectrics onto metals for insulation, etc.), screen printing, spraying, laser welding of discrete layers (e.g., different depths in different layers, etc.), laser patterning of polyimide films to allow plating (e.g., plating of FSS elements, etc.), casting, injection molding, rolling / forming processes, integrated parts incorporating pyramidal surfaces in the design, etc.

[0076] In an exemplary embodiment, a 3D printed mold insert may be used in conjunction with a compression or injection molding process. Pattern manufacturing may be performed in a vacuum oven. For example, a 3D printed master may be placed on a metal sheet. Then, a flat composite sheet (e.g., polycaprolactone filled with carbon black, etc.) made by compression molding may be placed on the 3D printed master and surrounded by a bracket. A weight (e.g., a metal block, etc.) may be placed on top of the composite sheet. The gravity of the weight on top of the composite sheet is used to create a pattern in the composite sheet from the concave pattern of the 3D printed master. The material is heated in the oven and then removed from the oven. The material is allowed to cool, and then the composite material is separated from the 3D printed master.

[0077] In an exemplary embodiment, a material with a pattern can be prepared in a filled dielectric system using a roll-to-roll process. The process may include self-aligning a self-patterned block copolymer roll-to-roll with sufficient particle loading for good or satisfactory performance. The patterned PDMS tape can be used for patterning together with a heating plate (which can be a tunnel oven, etc.). The patterned PDMS tape may include a plurality of concave patterned (e.g., silica gel, etc.) portions, the ends of which are combined or joined together using PDMS. PDMS can be cured along the joints between the ends of the concave patterned portions. The patterned PDMS tape is wound on a roller. The rollers can be spaced apart a sufficient distance to avoid sagging of the patterned PDMS tape.

[0078] During the roll-to-roll process, a carrier (e.g., an aluminum carrier with a release layer, etc.) of an uncured mixture of PDMS and carbon black (or other filled dielectric system) moves across a heated plate. The patterned PDMS tape contacts the uncured mixture of PDMS and carbon black. After a sufficient amount of contact time with the patterned PDMS tape to allow mold filling to be completed, the process can begin to cure the uncured mixture of PDMS and carbon black. The cured PDMS and carbon black parts can then be removed (e.g., peeled off, etc.) from the patterned PDMS tape and carrier.

[0079] In an exemplary embodiment, a stepwise deposition process may be used to provide a pattern along a material (e.g., Figures 1A to 1E In this exemplary embodiment, the process may include gradually depositing materials (e.g., thermally conductive, electrically conductive, EMI absorbing, magnetic and / or dielectric materials, etc.) onto the functional carrier film. The functional carrier film may include a filled dielectric system, such as polydimethylsiloxane (PDMS) filled with carbon black, a filled block copolymer system, a filled elastic system (e.g., a cured elastomer, a thermoplastic elastomer (TPE), a Santoprene thermoplastic vulcanizate, etc.), a filled thermoplastic system (e.g., liquid silicone, urethane, polycarbonate, polyamide, polyester, polyolefin, polybutylene terephthalate, thermoplastic vulcanizate, thermoplastic elastomer, a mixture including polyolefin, acrylonitrile butadiene styrene (ABS), polypropylene (PP), polyethylene (PE), etc.), an injection moldable resin filled with carbon nanotubes, a polymer resin filled with carbon nanotubes, etc. Functional carrier films may include Kapton polyimide films, Mylar polyester films, thermoplastic films that can be used for stereolithography (SLA) printing, and the like.

[0080] In an exemplary embodiment, the material may be deposited or otherwise applied to the functional carrier film by spraying, printing, additive manufacturing, etc. For example, the material may be applied to the functional carrier film by laser jet printing a first layer of material (e.g., conductive and / or thermally conductive ink, etc.) onto the functional carrier film. A second layer of the same or different material may be laser jet printed on top of the first layer. This may be performed as part of a roll-to-roll process with the addition of a laser jet printer.

[0081] In an exemplary embodiment, the film or layer may be provided with materials of different thicknesses or heights to accommodate the height variations of shorter and taller PCB components. For example, an additive manufacturing process may be used to apply thermally conductive materials of different thicknesses along the bottom layer of a multilayer film structure, such that when the multilayer film structure is mounted above a PCB component, thicker and thinner portions of the thermally conductive material will be disposed above and in compressive contact with the top surfaces of the shorter and taller PCB components, respectively. As another example, additive manufacturing may be used to apply thermally conductive material along the top surface of a shorter PCB component, thereby increasing the total height of the shorter component plus the thermally conductive material.

[0082] In an exemplary embodiment, the bottom film or layer of the multilayer film structure may be configured to allow the multilayer film structure to be removably separated from and reattached to the PCB, such as via adhesion, adhesive, mechanical attachment, etc. For example, the multilayer film structure may be attached to the PCB, removed from the PCB (e.g., to facilitate access to PCB components, etc.), and reattached to the PCB without damaging (e.g., without cutting, without stretching, etc.) the multilayer film structure.

[0083] The above process can be used to provide a variety of patterns of different structural shapes (e.g., quadrangular pyramids, pyramid structures, non-pyramidal structures, combinations thereof, etc.), including Figures 5 to 15 An exemplary pattern of structures is shown. The pattern of structures may also be provided by other suitable processes. For example, the pattern of structures may include a multilayer film, a single layer film, or a homogeneous layer / film having a full thickness domain tailored for a particular property as disclosed herein. Or, for example, the pattern of structures may include a metamaterial.

[0084] In an exemplary embodiment, the multilayer film (broadly, the multilayer structure) includes a plurality of block copolymer films or layers having a full thickness domain. As an example, the block copolymer may include a polystyrene-polyethylene block copolymer (e.g., polystyrene-block-poly (ethylene oxide) (PS-b-PEO), etc.), a polystyrene-acrylate block copolymer (e.g., polystyrene and poly (methyl methacrylate) (PS-PMMA), etc.), a styrene-diene block copolymer (e.g., styrene-butadiene (SB) diblock copolymer, styrene-isoprene diblock copolymer, styrene-butadiene-styrene (SBS) triblock copolymer, styrene-isoprene-styrene (SIS) triblock copolymer, styrene-butadiene (SB) star block copolymer, etc.), a hydrogenated styrene-diene block copolymer, a styrene-isoprene diblock copolymer, a styrene-butadiene-styrene (SBS) triblock copolymer, a styrene-isoprene-styrene (SIS) triblock copolymer, a styrene-butadiene (SB) star block copolymer, etc.), a Copolymers (e.g., hydrogenated SBS styrene-(ethylene-butylene)-styrene, etc.), segmented block copolymers (e.g., segmented polyester-polyether, segmented polyamide-polyether, etc.), polyolefin block copolymers, ethylene oxide / propylene oxide block copolymers, silicone copolymer systems (e.g., siloxane / polysulfone copolymers, siloxane / polyurethane, siloxane / polyurea copolymers, siloxane / polyamide copolymers, siloxane / polyimide copolymers, siloxane / polyamide / polyimide copolymers, siloxane / polyester copolymers, siloxane / polycarbonate copolymers, siloxane / polystyrene copolymers, siloxane / epoxy networks, etc.), hard block copolymers, other block copolymers, and / or combinations thereof. In an exemplary embodiment, the block copolymer film or layer includes polystyrene-block-poly(ethylene oxide) (PS-b-PEO) and / or polystyrene and poly(methyl methacrylate) (PS-PMMA), but other block copolymers may be used in other exemplary embodiments.

[0085] Specific fillers can be preferentially added to a domain, thereby enhancing the properties of the domain of the block copolymer film. In exemplary embodiments disclosed herein, one or more fillers are added to the domains of multiple block copolymer films, thereby tailoring the domains of multiple block copolymer films for specific properties (e.g., thermal management, electromagnetic interference (EMI) mitigation, electrical conductivity, thermal conductivity, EMI absorption, magnetic, dielectric and / or structural properties, etc.).

[0086] Multiple block copolymer films with tailored domains can be assembled (e.g., laminated, stacked, etc.) into a multilayer structure (e.g., a laminated structure, etc.). The multilayer structure can be manufactured by roll-to-roll processing, spin casting, extrusion, curtain coating, 3D printing, additive manufacturing (e.g., fused deposition modeling (FDM), stereolithography (SLA), laser direct structure (LDS), etc.), molding, etc.

[0087] In an exemplary embodiment, vertical orientation control and biased separation / dispersion of fillers (e.g., functional nanoparticles, nickel cobalt, boron nitride, coated filler particles, etc.) can be used to tailor the full-thickness domains of each film or layer to have specific electrical, thermal, magnetic, dielectric and / or structural properties. By controlling the domain size, shape and structure within multiple films or layers, the domains can be configured to create patterns (e.g., macroscopic patterns or hierarchical patterns based on patterns in individual layers, etc.) or gradients (e.g., impedance gradients constructed across domains of multilayer block copolymer films / layers by filler loading, etc.), etc.

[0088] Domains can be configured so that multiple layers have different functions. Domains within one layer can be configured differently or the same as domains in one or more other layers (e.g., for controlled performance, etc.).

[0089] Multiple films or layers can be configured differently from each other. For example, the films or layers can have different thicknesses, can include different fillers (e.g., different materials, sizes and / or shapes, etc.), can be made of different base or matrix materials, can have domains with different configurations (e.g., tailored to have different functions, different sizes, different locations, etc.), etc.

[0090] For example, a multilayer film structure may include a plurality of films or layers, at least one or more of which include a base or matrix material and / or a different type of filler than at least one or more other films or layers. In this example, the multilayer film structure may include a first film or layer including a first base or matrix material and a first type of filler (e.g., a thermally conductive filler, etc.). The multilayer film structure may also include a second film or layer including a second base or matrix material different from the first base or matrix material and a second type of filler different from the first type of filler (e.g., a conductive and / or EMI absorbing filler, etc.).

[0091] Alternative exemplary embodiments may include polymer films / layers as homogeneous or monolayer structures and / or unseparated block copolymers. For example, a homogeneous or monolayer film structure may include a specially made full thickness domain spaced apart from each other in a homogeneous or monolayer film structure to have specific electrical, thermal, magnetic, dielectric and / or structural properties. The vertical orientation control and biased separation / dispersion of fillers (e.g., functional nanoparticles, nickel cobalt, boron nitride, coated filler particles, etc.) may be used to space apart and specially make the full thickness domain in a homogeneous or monolayer film structure. By controlling the domain size, shape and structure in a homogeneous or monolayer film structure, the domain may be configured to create a pattern (e.g., a macroscopic pattern or hierarchical pattern based on a pattern in each layer, etc.) or a gradient (e.g., an impedance gradient constructed by a domain across each layer by a filler loading, etc.). The domain may be configured to make different spaced apart parts of a homogeneous or monolayer film structure have different functions. The domains in the first and second spaced apart parts of a homogeneous or monolayer film structure may be configured differently or identically from each other (e.g., for controlled performance, etc.).

[0092] Figure 3 A multilayer film structure 300 according to an exemplary embodiment embodying one or more aspects of the present disclosure is shown. As shown, the multilayer film structure 300 includes four films or layers 302, 304, 306, 308 and full-thickness domains 310, 312, 314, 316 in each of the four layers. In alternative embodiments, the multilayer film structure may be configured differently, such as having more or less than four layers, more or less full-thickness domains, etc.

[0093] The domains within the various layers may be tailored to have specific characteristics, properties, functions, and / or performance (e.g., electrical, thermal, magnetic, dielectric, and / or structural, etc.). As an example, the domain 310 in the first or top layer 302 may be configured for thermal performance. The domains 312, 314 in the respective second and third layers 304, 306 may be configured for EMI mitigation (e.g., conductive, EMI absorbing, magnetic, etc.). The domain 316 in the fourth or bottom layer 308 may be configured for dielectric performance.

[0094] The domains in each layer can create a pattern that is tailored or unique to that individual layer. The patterns of the individual layers can cooperate to define or create a macro pattern in the multilayer film structure (e.g., through its thickness, etc.). For example, the domains of one layer can be vertically aligned and / or at least partially overlapped with the domains of another layer, so that the vertically aligned and / or at least partially overlapping domains within a layer cooperate to define a pathway (e.g., an electrically and / or thermally conductive pathway, a via, a post, etc.) vertically through the thickness of the layer.

[0095] In an exemplary embodiment, domains of different layers may include vertically aligned thermally and / or electrically conductive fillers that create vertical through-thickness conduction pathways through the different layers. For example, a thermal pathway with relatively high thermal conductivity may be created that may be high enough to provide good performance even if the multilayer film structure has a relatively high contact resistance. Depending on the contact resistance of the multilayer film structure, a relatively thin, soft, and conformable thermally conductive layer may be added to reduce the contact resistance and better thermal performance.

[0096] Block copolymers can be used as Figure 3The base or matrix material 320 of one or more of the four films 302, 304, 306, 308 shown. For example, polystyrene-block-poly(ethylene oxide) (PS-b-PEO) can be used as the base or matrix material 320 of only one, two, three, or all of the films of the multilayer film structure 300. Or, for example, polystyrene and poly(methyl methacrylate) (PS-PMMA) can be used as the base or matrix material 320 of only one, two, three, or all of the films of the multilayer film structure 300. Different polymers can instead be selected to allow for larger domain sizes than can be achieved using polystyrene-block-poly(ethylene oxide) (PS-b-PEO) and / or polystyrene and poly(methyl methacrylate) (PS-PMMA). In other embodiments, a different base or matrix material may be used for one or more of the films, such as a polystyrene-polyethylene block copolymer, another polystyrene-acrylate block copolymer, a styrene-diene block copolymer (e.g., a styrene-butadiene (SB) diblock copolymer, a styrene-isoprene diblock copolymer, a styrene-butadiene-styrene (SBS) triblock copolymer, a styrene-isoprene-styrene (SIS) triblock copolymer, a styrene-butadiene (SB) radial block copolymer, etc.), a hydrogenated styrene-diene block copolymer (e.g., a hydrogenated SBS styrene-(ethylene-)ethylene-bis(ethylene) ... butylene)-styrene, etc.), segmented block copolymers (e.g., segmented polyester-polyether, segmented polyamide-polyether, etc.), polyolefin block copolymers, ethylene oxide / propylene oxide block copolymers, silicone copolymer systems (e.g., siloxane / polysulfone copolymers, siloxane / polyurethane, siloxane / polyurea copolymers, siloxane / polyamide copolymers, siloxane / polyimide copolymers, siloxane / polyamide / polyimide copolymers, siloxane / polyester copolymers, siloxane / polycarbonate copolymers, siloxane / polystyrene copolymers, siloxane / epoxy resin networks, etc.), hard block copolymers, other block copolymers and / or combinations thereof.

[0097] A wide variety of fillers can be included into the base or matrix material 320 of the membrane to tailor, modify and / or functionally adjust the properties of the resulting membrane. Fillers can include functional nanoparticles, conductive fillers, thermally conductive fillers, EMI or microwave absorbing fillers, magnetic fillers, dielectric fillers, coating fillers, combinations thereof, etc. Fillers can be added and mixed into a bulk material including a base or matrix material, thereby providing a mixture of filler and base or matrix material. Example fillers include carbon black, boron nitride, nickel cobalt, air-filled microballoons, air-filled microbubbles, air-filled microspheres, carbonyl iron, iron silicide, iron particles, iron-chromium compounds, silver, alloys containing 85% iron, 9.5% silicon and 5.5% aluminum, alloys containing about 20% iron and 80% nickel, ferrites, magnetic alloys, magnetic powders, magnetic flakes, magnetic particles, nickel-based alloys and powders, chromium alloys, aluminum oxide, copper, zinc oxide, aluminum oxide, aluminum, graphite, ceramics, silicon carbide, manganese zinc, glass fibers, carbon nanotubes (e.g., single-walled carbon nanotubes, multi-walled carbon nanotubes and / or carbon nanostructures, etc.), combinations thereof, etc. The filler may include granules, spheres, microspheres, ellipsoids, irregular spheres, strands, flakes, powders, nanotubes, and / or any or all combinations of these shapes. In addition, exemplary embodiments may also include different grades (e.g., different sizes, different purities, different shapes, etc.) of the same (or different) fillers.

[0098] In an exemplary embodiment, a film of a multilayer film structure (e.g., Figure 3 The films 302, 304, 306 and / or 308, etc., of the illustrated multi-layer film structure 300 may be made by casting, film extrusion, lamination, etc.

[0099] Figure 4 An exemplary embodiment of a multilayer film structure 400 (e.g., a four-layer film structure, etc.) according to an exemplary embodiment that specifically implements one or more aspects of the present disclosure is shown. In this exemplary embodiment, as indicated by the arrows, the packing density of each layer increases in the direction from the top layer 402 to the bottom layer 408. Therefore, the bottom layer 408 has the highest packing density, while the top layer 402 has the lowest packing density. Regarding the two middle layers 404 and 406 between the top layer 402 and the bottom layer 408, the lower middle layer 406 has a higher packing density than the upper middle layer 406. The total thickness or height dimension of the multilayer film structure 400 may be approximately 1.7 millimeters (mm). However, the 1.7 mm dimension is provided for illustration only, as in other embodiments the multilayer film structure may be thicker or thinner than 1.7 mm. In addition, Figure 4 The illustrated multilayer film structure 400 includes four layers 402 , 404 , 406 , 408 , but other exemplary embodiments may include multilayer film structures having more or less than four layers.

[0100] In an exemplary embodiment, a multilayer film structure may include a film having functionality (e.g., for electrical, thermal, absorber, magnetic, dielectric, and / or structural, etc.) in separate discrete regions. For example, a multilayer film structure may include a film configured to have thermal management functionality, EMI shielding functionality, and EMI absorption functionality in separate discrete regions of the multilayer film structure.

[0101] The multilayer film structure may have different loadings within the layers or films for different properties, effects, etc. For example, the multilayer film structure may have different loadings from layer to layer, which may be operable to be used in accordance with Figures 5 to 15 , Fig.21A , Fig. 21B The pyramidal or non-pyramid structures shown in and described herein can mitigate EMI in a manner similar to the EMI mitigation provided by the pyramidal or non-pyramid structures shown in and described herein (e.g., absorbing high frequency EMI, etc.).

[0102] In an exemplary embodiment, the multilayer film structure and / or patterned material may be provided with a backing, for example, via a metallization process, lamination, tape casting, vacuum deposition, other suitable processes, combinations thereof, etc. The backing may include one or more metals (e.g., aluminum, copper, etc.), coated metals (e.g., nickel-clad aluminum, etc.), clad metals, metallized polymer films / plastics, aluminized Mylar biaxially oriented polyethylene terephthalate (BoPET), other backing materials, combinations thereof, etc. For example, a backing may be provided along an outer exposed surface (e.g., Figure 3 or Figure 4 A backing including a metal (e.g., aluminum, copper, etc.) is provided (e.g., via a metallization process, etc.) on the bottom surface of the multilayer film structure 300 and / or 400 shown, respectively. Alternatively, for example, a patterned material may be provided along the bottom surface (e.g., Figure 5 , Figure 6 or Fig.21A , Fig. 21B The bottom surface of the patterned materials 500, 600 and / or 2100, respectively, etc., is provided (eg, via a metallization process, etc.) with a backing including a metal (eg, aluminum, copper, etc.).

[0103] In an exemplary embodiment, the multilayer film structure and / or patterned material may have a relatively high contact resistance, depending on the materials used. Alternatively, for example, the multilayer film structure and / or patterned material may be provided with one or more thermally conductive pillars (broadly, portions) having very high thermal conductivity to help compensate and / or overcome the relatively high contact resistance.

[0104] In an exemplary embodiment, one or more thermal interface materials, heat sinks, thermoelectric modules, etc. can be used with the multilayer film structure and / or patterned material. For example, a heat sink (e.g., a graphite heat sink, etc.) can be disposed along the multilayer film structure (e.g., laminated to, sealed between films via laser welding, etc.). Alternatively, for example, a thermoelectric module can be disposed along the multilayer film structure.

[0105] As another example, a thermal interface material can be disposed along the top surface and / or bottom surface of the multilayer film structure. In this latter example, the thermal interface material can help accommodate height variations of shorter and taller PCB components. For example, the thermal interface material can be disposed along the bottom surface of the multilayer film structure so that when the multilayer film structure is mounted above the PCB component, the thermal interface material will be disposed above the top surface of the PCB component and in compressive contact therewith. The thermal interface material can also be disposed along the top surface of the multilayer film structure so that the thermal interface material compressively contacts a heat sink (e.g., a housing or device housing, etc.). Example thermal interface materials include thermal gap fillers, thermal phase change materials, thermally conductive EMI absorbers or hybrid thermal / EMI absorbers, thermally conductive grease, thermally conductive paste, thermally conductive putty, dispensable thermal interface materials, thermally conductive pads, etc.

[0106] Exemplary embodiments may include one or more radiating antenna elements defined or created by domains in one or more layers or films of a multilayer film structure, a homogeneous film structure, or a single-layer film structure. Exemplary embodiments may include a film structure (e.g., a multilayer film structure, a homogeneous film structure, a single-layer film structure, etc.) comprising one or more layers or films configured to provide environmental protection (e.g., a vapor or oxygen barrier, etc.) (e.g., having a domain tailored therefor, etc.). Exemplary embodiments may include one or more waveguides defined or created by domains in one or more layers or films of a multilayer film structure, a homogeneous film structure, or a single-layer film structure. Thus, exemplary embodiments may include a multilayer film structure having multiple layers or films having domains configured to provide one or more radiating antenna elements, one or more waveguides, EMI mitigation, thermal management, dielectric properties, structures, and / or environmental protection, etc. Exemplary embodiments may also include homogeneous or single layer film structures having a single or monolayer or film having domains configured to provide one or more radiating antenna elements, one or more waveguides, EMI mitigation, thermal management, dielectric properties, structural and / or environmental protection, etc.

[0107] Figures 5 to 15 and Fig.21A , Fig. 21B An exemplary structure (e.g., a pyramid structure, a non-pyramid structure, etc.) configured for EMI mitigation (e.g., absorbing high frequencies, etc.) according to an exemplary embodiment is shown in which one or more aspects of the present disclosure are embodied. Figures 7 to 15In a board level shield (BLS), a structure may be disposed along (e.g., attached to, etc.) and protrude outwardly from a portion of the board level shield (BLS). For example, the structure may protrude outwardly from an inner surface and / or outer surface of a BLS top, cover, lid, sidewall, fence, frame, etc. The BLS may be configured (e.g., made of metal, shaped, sized, etc.) to mitigate (e.g., block, reflect, etc.) low frequency EMI. The structure may be configured (e.g., made of EMI absorbing material, shaped, sized, etc.) to mitigate (e.g., absorb, etc.) high frequency EMI.

[0108] Figures 5 to 15 and Fig.21A , Fig. 21B An exemplary pyramid structure is shown as a quadrangular pyramid. The rectangular bases of adjacent pyramids may contact each other without substantially any gaps or separation distances between the rectangular bases. This helps to avoid reflectivity that may occur if there are gaps between the rectangular bases of the pyramid structures. Other exemplary embodiments may include non-pyramid structures that taper or decrease in width (e.g., curve generally smoothly, etc.) from the top (e.g., from a point, etc.) toward the base. For example, Fig.14 and Fig.15 Exemplary embodiments are shown to include non-pyramid structures 1400, 1500, respectively. Alternative exemplary embodiments may include structures with non-rectangular bases (e.g., hexagonal bases, triangular bases, etc.). Therefore, the present disclosure should not be limited to only quadrangular pyramid structures, as other exemplary embodiments may include structures with different three-dimensional geometries.

[0109] In an exemplary embodiment, the side of the structure may not be completely smooth or define a perfect straight line from top to bottom. For example, when viewed at a high magnification, the side may appear to have a stepped configuration. However, the side of the pyramidal or non-pyramid structure may preferably be relatively smooth (e.g., without any significant steps of any size, etc.) to reduce or avoid reflections of EMI incident on the structure. In addition, the structure may be configured to have a varying slope or taper along the side (e.g., at least two or more slopes, etc.). For example, a pyramidal structure may have a relatively gentle taper from the base toward the middle portion, a more rapid taper from the middle portion toward the top, and then a smaller taper from there to the top of the structure.

[0110] Figures 5 to 15 and Fig.21A , Fig. 21B The structure shown can be FIG. 2A to FIG. 2E Prepared by the process shown in and described above. Figures 5 to 15 and Fig.21A , Fig. 21BThe structures shown may include filled dielectrics, such as polydimethylsiloxane (PDMS) filled with carbon black, filled block copolymer systems, filled elastomeric systems, filled thermoplastic systems, etc. Alternatively, Figures 5 to 15 and Fig.21A , Fig. 21B The structures shown may be made of other materials and / or by other suitable processes (e.g., gradually depositing materials onto a functional carrier film, etc.). The structures may include one or more first structures along a first layer and one or more second structures along a second layer. The first and second structures may be configured differently, e.g., different shapes, different heights, made of different materials, etc.

[0111] In an exemplary embodiment, the configuration of the structures (e.g., height, shape, position, etc.) can be non-randomized or randomized (e.g., via a computer randomization process, etc.). Randomizing the height of the structures along the interior of the BLS can help reduce or avoid cavity resonances under the BLS. An exemplary embodiment can include four-sided pyramid structures with bases of the same size, but one or more of the four-sided pyramid structures can have a different height than one or more other four-sided pyramid structures. For example, taller pyramids can be arranged along an edge or periphery, while shorter pyramids can be arranged in a middle or inner portion spaced inwardly from the edge or periphery.

[0112] Structures with different heights can be used to accommodate the height variations of shorter and taller PCB components. For example, taller and shorter structures can be disposed along the inner surface of a BLS cover or lid so that when the BLS is mounted above the PCB components, the taller and shorter structures are disposed substantially above the shorter and taller PCB components, respectively. The different heights of the structures can also help avoid or reduce cavity resonances beneath the BLS.

[0113] Figure 5 A filling dielectric 538 including a pyramid structure 540 according to an exemplary embodiment 500 embodying one or more aspects of the present disclosure is shown. As shown, the pyramid structure 540 includes air-filled particles 542 (e.g., air-filled micro-balloons, air-filled micro-bubbles, air-filled micro-spheres, etc.) within the filling dielectric 538. The air-filled particles 542 add air to the pyramid structure 540, which reduces (e.g., controllably reduces, etc.) the dielectric constant. With the air-filled particles 542 therein, the dielectric constant of the pyramid structure 540 can approximate the dielectric constant of a foam and / or approach the dielectric properties of a foam.

[0114] In addition to or alternatively to loading or filling the air-filled particles 542, in other exemplary embodiments, the pyramidal and / or non-pyramidal structures may be covered or coated by a polymer including air-filled particles (e.g., air-filled microballoons, air-filled microbubbles, air-filled microspheres, hollow glass, plastic and / or ceramic microspheres, other microspheres, etc.). For example, an exemplary embodiment may include a pyramidal structure coated or covered by a microballoon-filled polymer (e.g., for environmental resistance, etc.). In this example, the microballoon-filled polymer may cover the pyramidal structures and define a flattening layer for filling the spaces between the pyramidal structures. The inverted pyramidal structures of the flattening microballoon-filled polymer layer may be interlaced or interwoven with the pyramidal structures so that the combined pyramidal structures and the flattening microballoon-filled polymer layer have a generally flat sheet-like configuration. The flattening microballoon-filled polymer layer may be operable to inhibit or prevent dust and / or other debris from filling the spaces, holes, openings, gaps, etc. between the pyramidal structures. As an example, the microballoon filling polymer may include a low dielectric loss, low dielectric constant (e.g., less than 10, between 1 and 2, less than 1, etc.) material, such as Laird's LoK low dielectric loss, low dielectric constant materials including thermoset plastics or silicone and hollow glass microspheres, etc. Alternatively, in other exemplary embodiments, other materials (e.g., including materials that are not low dielectric loss, low dielectric constant materials and / or do not include hollow glass microspheres, etc.) may be used to define a planarization layer and / or to cover or coat the pyramids and / or non-pyramid structures to inhibit or prevent dust and / or other debris from filling the spaces, holes, openings, gaps, etc. between the pyramids and / or non-pyramid structures. Therefore, aspects of the present disclosure include methods of inhibiting or preventing dust and / or other debris from filling the spaces, holes, openings, gaps, etc. between the pyramid structures and / or non-pyramid structures disclosed herein.

[0115] Figure 6 An EMI absorber 644 including a pyramid structure 640, a planarization layer 646, and a multi-layer frequency selective surface (FSS) structure 648 according to an exemplary embodiment 600 embodying one or more aspects of the present disclosure is shown. As shown, the EMI absorber 644 and the pyramid structure 640 may include polydimethylsiloxane (PDMS) filled with carbon black, a filled block copolymer system, a filled elastomeric system (e.g., cured elastomer, thermoplastic elastomer (TPE), Santoprene thermoplastic vulcanizate, etc.), a filled thermoplastic system (e.g., polyamide, acrylonitrile butadiene styrene (ABS), polypropylene (PP), polyethylene (PE), etc.), an injection moldable resin filled with carbon nanotubes, a polymer resin filled with carbon nanotubes, etc.

[0116] like Figure 6As shown, the planarization layer 646 includes or defines downwardly protruding inverted pyramid structures 650 for filling spaces between the upwardly protruding pyramid structures 640 of the EMI absorber 644. The inverted pyramid structures 650 of the planarization layer 646 may be interlaced or interwoven with the pyramid structures 640 such that the combination of the EMI absorber 644 and the planarization layer 646 has a generally flat sheet-like configuration.

[0117] The planarization layer 646 may include dielectric materials (e.g., gradient dielectrics for impedance matching, uniform dielectric planarization layers, etc.), thermally conductive materials, electrically conductive materials, etc. The planarization layer 646 may help strengthen the pyramid structures, protect against fracture of the pyramid structures 640, provide adhesion, provide rigidity or structure for attachment and / or adjust elastic modulus, and / or inhibit or prevent dust and / or other debris from filling spaces, holes, openings, gaps, etc. between the pyramid structures 640. The planarization layer 646 may be provided with different thicknesses to accommodate height variations of shorter and taller components of a PCB, SIP, etc.

[0118] In exemplary embodiments where the planarization layer is conductive, one or more dielectric materials (e.g., a thin dielectric layer, etc.) may be disposed along the exposed outer surface portion of the planarization layer to prevent adjacent device components from shorting through the conductive planarization layer. As another example, when a TIM is used as a planarization layer (e.g., injection molding, etc.), the dielectric material may be embedded in the thermal interface material (TIM). In other exemplary embodiments including EMI absorbing structures (e.g., Figure 5 , Figures 7 to 15 and Fig.21A , Fig. 21B etc.) can also use the planarization layers described herein (e.g., Figure 6 646 etc. shown).

[0119] Figure 6 The illustrated multi-layer frequency selective surface (FSS) structure 648 includes a multi-layer (e.g., three layers, etc.) FSS element 652. Alternative embodiments may include FSS structures having more or less than three layers (e.g., a single layer, two layers, four layers, etc.). For example, Fig.19 An exemplary embodiment 1900 of a multi-layer FSS structure 1948 is shown including four layers 1902, 1904, 1906, 1908 of FSS elements 1952. Alternatively, for example, exemplary embodiments may include a single layer of FSS elements, multiple coplanar rings in a single plane, conductive metamaterials in a pattern on a dielectric along the bottom side of the BLS and / or along a ground plane, etc. Thus, the present disclosure should not be limited to only three or four layer FSS structures.

[0120] like Figure 6 and Fig.19As shown, the layers of a multi-layer frequency selective surface (FSS) structure 648, 1948, respectively, include patterns of FSS elements 652, 1952. The FSS elements may include conductive materials, EMI absorbing materials, and / or metamaterials.

[0121] exist Figure 6 and Fig.19 In the illustrated embodiment, the FSS element 652, 1952 comprises an annular element (e.g., a ring, a substantially annular element, etc.) having an open area or opening. As an example, the open area or opening may include perforations or holes punched into the layer for airflow before or after providing the FSS element (e.g., laser patterning onto the layer, etc.). Alternatively, for example, the open area or opening may be formed by etching or cleaning a cured / uncured polymer from the FSS element. As another example, the FSS layer may be prepared using a mold configured to create the open area or opening.

[0122] like Figure 6 As shown, the multiple layers of the multilayer FSS structure 648 can be arranged in a stacked manner (e.g., a laminated structure, etc.) such that the FSS elements 652 of each layer overlap and are vertically aligned with the FSS elements 652 in other layers. The openings or open areas of each layer are thus vertically aligned with the openings or open areas of other layers. Therefore, since air and / or liquid can flow within the vertically aligned openings or open areas, the FSS elements 652 can be used to mitigate EMI without completely blocking the flow of air and / or liquid through the multilayer FSS structure. Alternative embodiments may include a multilayer FSS structure configured such that all FSS elements do not overlap and are not vertically aligned with other FSS elements (e.g., Fig.19 1948 etc.) and / or include FSS elements configured to have no openings or open areas.

[0123] In an exemplary embodiment, a multi-layer FSS structure (e.g., 648 ( Figure 6 )、1948( Fig.19 ) and the like) may include block copolymers, polydimethylsiloxane (PDMS), thermoplastic films prepared by the process disclosed herein, and the like.

[0124] Multilayer FSS structure (e.g., 648( Figure 6 )、1948( Fig.19) etc.) may include multiple films or layers having FSS elements provided by the processes disclosed herein. As an example, the FSS structure may include an FSS element comprising copper and a film or layer comprising Mylar biaxially oriented polyethylene terephthalate (BoPET). In this example, the copper pattern of the FSS element may be etched onto the Mylar BoPET film or layer using the FR4 / PCB manufacturing process. As another example, the FSS element may be disposed along the film or layer by 3D printing or additive manufacturing (e.g., fused deposition modeling, stereolithography, laser direct construction with modeling, etc.). Alternatively, for example, the FSS element may include a conductive ink (e.g., ink comprising silver and / or copper, etc.) inkjet printed along the film or layer (e.g., via a microjet inkjet printer, etc.). As another example, an impregnated plastic film may include portions that become conductive after being struck by a laser, which conductive portions define conductive FSS elements. As another example, the film or layer of the multilayer FSS structure may be impregnated with, embedded with, and / or printed with one or more materials to generate a patterned conductivity region (e.g., ring, etc.) defining the FSS surface. Other processes may also be used to provide a film or layer with a FSS element.

[0125] Films with conductive FSS elements can be assembled (eg, stacked, laminated, etc.) together to form a multi-layer FSS structure. The FSS elements can be supported by an absorber to reduce the absorber frequency.

[0126] In an exemplary embodiment, the FSS structure (e.g., 648 ( Figure 6 )、1948( Fig.19 ) etc.) can be operated to block energy across one or more specific frequencies or frequency ranges while also allowing one or more different specific frequencies or frequency ranges to pass. In this case, the FSS structure can be used as a single-band or multi-band bandpass waveguide and / or EMI mitigation structure.

[0127] In an exemplary embodiment, one or more FSS elements may have a different shape and / or size than one or more other FSS elements.For example, another exemplary embodiment may include a FSS structure having FSS ring elements of varying thickness and / or varying radius.

[0128] In an exemplary embodiment, the layers of the multi-layer FSS structure can be of any shape (e.g., rectangular, circular, triangular, etc.) and / or size, e.g., to operate at multiple frequencies and / or over a wider bandwidth, etc. In operation, the FSS structure can reflect, absorb, block and / or redirect signals at near-grazing incidence (90 degrees off normal) to stop the energy.

[0129] Figure 7A pyramid structure 740 is shown along a portion (e.g., top, cover, lid, sidewall, fence, frame, etc.) of a board level shield (BLS) 754 according to an exemplary embodiment 700 embodying one or more aspects of the present disclosure. Figure 7 In the example shown, the pyramid structure 740 is a quadrangular pyramid with a rectangular base. The pyramid structure 740 can be arranged along the BLS (e.g., Fig.11 , Fig.12 and Fig.13 The pyramid structure 740 may be configured to mitigate (e.g., absorb, etc.) high frequency EMI. The BLS 754 may be configured (e.g., made of metal, etc.) to mitigate (e.g., block, etc.) low frequency EMI.

[0130] Figure 8 A pyramid structure 840 is shown along a portion (e.g., top, cover, lid, sidewall, fence, frame, etc.) of a board level shield (BLS) 854 according to an exemplary embodiment 800 embodying one or more aspects of the present disclosure. Figure 8 In the example shown, the pyramid structure 840 is a four-sided pyramid with a rectangular base. In this example, the dimensions of the pyramid structures 840 are not all the same. For example, the two inner pyramid structures are shown to have different heights, which are less than the heights of the two outer pyramid structures. The pyramid structure 840 can be configured to mitigate (e.g., absorb, etc.) high-frequency EMI. The BLS 854 can be configured (e.g., made of metal, etc.) to mitigate (e.g., block, etc.) low-frequency EMI.

[0131] Fig. 9 A pyramid structure 940 is shown along a portion (e.g., top, cover, lid, sidewall, fence, frame, etc.) of a board level shield (BLS) 954 according to an exemplary embodiment 900 embodying one or more aspects of the present disclosure. Fig. 9 In the example shown, the pyramid structure includes air-filled micro-balloons, micro-spheres, micro-bubbles 942, etc. The air added by the micro-balloons, micro-spheres, or micro-bubbles 942 reduces the dielectric constant of the pyramid structure 940. The pyramid structure 940 is a four-sided pyramid with a rectangular base. The pyramid structure 940 can be configured to mitigate (e.g., absorb, etc.) high-frequency EMI. The BLS 954 can be configured (e.g., made of metal, etc.) to mitigate (e.g., block, etc.) low-frequency EMI.

[0132] Fig.10 A pyramid structure 1040 is shown along a portion (e.g., top, cover, lid, sidewall, fence, frame, etc.) of a board level shield (BLS) 1054 according to an exemplary embodiment 1000 embodying one or more aspects of the present disclosure. Fig.10 In the example shown, at least one or more pyramid structures 1040 are multi-layered. Fig.10 As shown, as indicated by the arrows, the packing density of each layer of the multilayer pyramid structure 1040 increases in the direction from the top layer to the bottom layer. Therefore, the bottom layer has the highest packing density, while the top layer has the lowest packing density. Regarding the two middle layers between the top layer and the bottom layer, the lower middle layer has a higher packing density than the upper middle layer. The pyramid structure 1040 can be configured to mitigate (e.g., absorb, etc.) high-frequency EMI. The BLS1054 can be configured (e.g., made of metal, etc.) to mitigate (e.g., block, etc.) low-frequency EMI.

[0133] By way of example only, the multilayer pyramid structure may have an overall height of about 2 mm or less and layers of about 100 microns thick. However, these dimensions are provided for illustration only, as the multilayer pyramid structure may have a different overall height and / or layers of different thicknesses. Additionally, Fig.10 The illustrated multilayer pyramid structure 100 includes four layers, but other exemplary embodiments may include multilayer pyramid structures having more or less than four layers. A varying gradient of filler material may be used for a multilayer film absorber structure (e.g., multilayer pyramid structure 1040, etc.). The multilayer film absorber structure (e.g., multilayer pyramid structure 1040, etc.) may be sufficiently flexible to be wrapped around at least a portion of a shield, device, etc.

[0134] Fig.11 , Fig.12 and Fig.13 Pyramidal structures 1140, 1240, 1340 along the top and sidewalls of board level shields (BLS) 1154, 1254, 1354, respectively, according to exemplary embodiments 1100, 1200, 1300 are shown embodying one or more aspects of the present disclosure. The BLS is generally mounted above an integrated circuit (IC) (broadly, a component or heat source) on a PCB (broadly, a substrate). The pyramidal structures can be configured to mitigate (e.g., absorb, etc.) high frequency EMI. The BLS can be configured (e.g., made of metal, etc.) to mitigate (e.g., block, etc.) low frequency EMI.

[0135] exist Fig.11 In the illustrated exemplary embodiment 1100 , the pyramidal structures 1140 are shown protruding inwardly from the inner surfaces of the BLS top 1156 and the BLS sidewalls 1158 in a direction generally toward the integrated circuit 1160 on the PCB 1162 .

[0136] exist Fig.12In the illustrated exemplary embodiment 1200 , the pyramidal structures 1240 are shown protruding outwardly from the outer surfaces of the BLS top 1256 and the BLS sidewalls 1258 in a direction generally away from the integrated circuit 1260 on the PCB 1262 .

[0137] exist Fig.13 In the illustrated exemplary embodiment 1300 , the pyramidal structure 1340 is shown along both the inner and outer surfaces of the BLS top 1356 and the BLS sidewall 1358 such that the pyramidal structure 1340 protrudes inwardly and outwardly in opposite directions relative to the BLS 1354 and the integrated circuit 1360 on the PCB 1362 .

[0138] Fig.14 Pyramid structures 1440 and non-pyramid structures 1464 along a portion (e.g., top, cover, lid, sidewall, fence, frame, etc.) of a board level shield (BLS) 1454 according to an exemplary embodiment 1400 are shown, embodying one or more aspects of the present disclosure. The pyramidal and non-pyramid structures 1440, 1464 can be configured to mitigate (e.g., absorb, etc.) high frequency EMI. The BLS 1454 can be configured (e.g., made of metal, etc.) to mitigate (e.g., block, etc.) low frequency EMI. Fig.14 As shown, the non-pyramid structure 1464 has a varying slope or taper along its sides.

[0139] Fig.15 A structure 1564 is shown along a portion (e.g., top, cover, lid, sidewall, fence, frame, etc.) of a board level shield (BLS) 1554 according to an exemplary embodiment 1500 embodying one or more aspects of the present disclosure. The structure 1564 can be configured to mitigate (e.g., absorb, etc.) high frequency EMI. The BLS 1554 can be configured (e.g., made of metal, etc.) to mitigate (e.g., block, etc.) low frequency EMI.

[0140] like Fig.15 As shown, each overall structure 1564 is generally upright and extends generally perpendicular to the portion of the BLS 1554. Each structure 1564 includes pyramids 1566 along two sides, and these pyramids 1566 extend generally outward from the structure 1564 in a direction generally parallel to the BLS portion 1554. By having pyramids 1566 along two sides of the structure 1564, Fig.15 The illustrated double-sided structure 1564 may have improved deflection and reduced contact resistance.

[0141] In an exemplary embodiment, the EMI absorbing protrusion structure (e.g., Figures 5 to 15 and Fig.21A , Fig. 21BIn some embodiments, the EMI absorbing protrusion structure may be provided with an inert non-functional material (e.g., a protective coating, etc.) along (e.g., attached to, etc.) one or more exposed and / or flat surfaces. In these embodiments, an inert non-functional material (e.g., a protective coating, etc.) may be applied to (e.g., coated to, etc.) the EMI absorbing protrusion structure. The inert non-functional material may be configured to protect the EMI absorbing protrusion structure from deformation (and loss of performance) and / or allow the EMI absorbing protrusion structure to be pressed onto a surface without interfering with (e.g., without significantly degrading, etc.) the function or performance of the EMI absorbing protrusion structure.

[0142] An exemplary embodiment includes a method of attaching an EMI absorbing protrusion structure to a surface. In this exemplary embodiment, the method may include applying a protective coating over the three-dimensional shape of the EMI absorbing protrusion structure. The method may also include applying a compressive force to the protective coating to ensure high bond strength (or PSA adhesion) to the surface. The protective coating may be removable and / or inert (e.g., dielectric, non-absorbent, etc.).

[0143] Also disclosed herein are exemplary embodiments of device components including (e.g., integrally including, made of, etc.) multilayer film structures, patterned materials, metamaterials, and / or functional films. In exemplary embodiments, multilayer film structures, patterned materials, metamaterials, and / or functional films may be included in device components and / or used as device components, such as housings, back covers, mid-plates, screen plates, inner plates, the outer skin of devices, inserts, IC packages, etc. In these embodiments, device components may retain their original functions, but also have additional functions (e.g., EMI mitigation, thermal management, dielectric, magnetic, and / or structure, etc.) provided by multilayer film structures, patterned materials, metamaterials, and / or functional films. As an example, multilayer film structures, patterned materials, metamaterials, and / or functional films may be included in the housing or outer skin of devices (e.g., smart phones, game system consoles, smart watches, 5G packaged antennas (AIP), etc.) and / or may be used as the housing or outer skin of devices.

[0144] In an exemplary embodiment, a multilayer film structure, patterned material, metamaterial and / or functional film can be used to transfer heat from one or more hotter parts or regions of a device (e.g., PCB components, etc.) to one or more cooler parts or regions (e.g., other PCB components, unused portions of the PCB, etc.). By considering the device as a whole for thermal management purposes, rather than treating each individual component separately and transferring heat based on a single component, exemplary embodiments can allow for more uniform device temperatures and improved device thermal properties, even though individual components may be heated due to heat transfer from other components. Therefore, exemplary embodiments can include using other parts of the electronic device as a heat sink so that heat is transferred from one component to another component or unused portion of the PCB. For example, an inner panel of an electronic device can include a multilayer film structure, patterned material, metamaterial and / or functional film for providing thermal management. The multilayer film structure, patterned material, metamaterial and / or functional film of the inner panel can extract waste heat from one or more regions and transfer / distribute the waste heat to one or more other regions, which can heat and increase the temperature of these one or more other regions of the electronic device. This in turn can make the device temperature more uniform and allow heat to be dissipated more evenly.

[0145] Fig.16 An outer device housing 1668 including a multi-layer film structure (e.g., a four-layer film structure, etc.) and / or a metamaterial 1670 according to an exemplary embodiment 1600 is shown embodying one or more aspects of the present disclosure. Fig.16 In the illustrated exemplary embodiment 1600 , the outer device housing 1668 includes four layers 1602 , 1604 , 1606 , 1608 that may be configured to provide one or more of a conductor 1672 , a waveguide 1674 , an EMI absorber 1676 , a thermal interface material (TIM) 1678 , and a dielectric 1680 .

[0146] The waveguide 1674 provided by the multi-layer film structure and / or metamaterial 1670 is operable to guide waves from the PCB component 1681 on the PCB 1662. The thermal interface material 1678 provided by the multi-layer film structure and / or metamaterial 1670 is operable to establish a thermally conductive heat path from the PCB component 1682 to the exterior of the outer device housing 1668.

[0147] The multilayer film structure and / or metamaterial 1670 can be configured to allow desired signals to pass (e.g., bandpass, etc.) at the enclosure or external device level, while rejecting and preventing other undesired signals from passing (e.g., bandstop, etc.). The multilayer film structure and / or metamaterial 1670 can be used to mitigate EMI via directional signal manipulation in the external device housing 1668.

[0148] The outer device housing 1668 may also or alternatively include an FSS structure (e.g., 648 ( Figure 6 )、1948( Fig.19 ) etc.). For example, the conductive metamaterial in a pattern may be disposed along an inner surface of the outer device housing 1668.

[0149] Thus, the exemplary embodiments disclosed herein may include a multifunctional outer device housing 1668 in that the outer device housing 1668 retains its original function as an outer device housing 1668. However, the outer device housing 1668 also includes additional functionality, such as functionality associated with the waveguide 1674 and thermal interface material 1678 provided by the multilayer film structure and / or metamaterial 1670. Fig.16 In the illustrated embodiment, the outer device housing 1668 includes four layers 1602, 1604, 1606, 1608, although other exemplary embodiments may include an outer device housing having more or less than four layers.

[0150] Fig.17 An insert 1768 including a multi-layer film structure (eg, a four-layer film structure, etc.) and / or a metamaterial 1770 according to an exemplary embodiment 1700 is shown embodying one or more aspects of the present disclosure. Fig.17 In the illustrated exemplary embodiment 1700 , a multi-layer film structure and / or metamaterial insert 1770 is positioned or sandwiched between two PCBs 1762 and 1763 .

[0151] The multilayer film structure and / or metamaterial insert 1770 may be configured to provide one or more of a conductor 1772, a waveguide 1774, an EMI absorber 1776, a thermal interface material (TIM) 1778, and a dielectric 1780 inserted between the two lower PCBs 1762 and the upper PCB 1763. The multilayer film structure and / or metamaterial insert 1770 may be a selective functional structure, such as to connect the two sandwiched PCBs to form an electrical interconnection, provide EMI shielding, and / or provide a thermal conductive path, etc. The multilayer film structure and / or metamaterial insert 1770 may include a portion having a relatively high dielectric constant, so that the two PCBs 1762, 1763 are capacitively coupled via the insert portion having a high dielectric constant.

[0152] In an exemplary embodiment, an interposer is provided for connecting two PCBs or SIPs with components via electrical connection traces between the molding (eg, injection molding, etc.) of the functional block copolymer and the SIP. Fig.17In the exemplary embodiment shown, insert 1768 includes four layers 1702, 1704, 1706, 1708, although other exemplary embodiments may include inserts having more or less than four layers.

[0153] Insert 1768 may be configured to allow interconnection between PCBs 1762, 1763 as desired while also having loaded EMI properties. Inserts 1762, 1763 may be positioned between two PCBs 1762, 1763, each including at least one component 1781, 1782, 1783, 1784 thereon. As disclosed herein, insert 1768 may include a block copolymer of at least two polymers and one or more fillers. Insert 1768 may include at least one electrical trace that passes through insert 1768 to provide at least one electrical connection between at least one component on one circuit board and at least one component on another circuit board. For example, Fig.17 The illustrated insert 1768 may provide electrical connections between the PCB components 1781 , 1782 on the lower PCB 1762 and the corresponding PCB components 1783 , 1784 on the upper PCB 1763 .

[0154] Exemplary embodiments may include patterning the functions in the multilayer film structure to match the layout of the components on two or more PCBs. When the PCBs are clamped together, the patterned multilayer film structure can provide electrical interconnection and other functions between the components on the PCBs. In exemplary embodiments, patterned films can be created to provide electrical interconnection for SIP (system in package). In exemplary embodiments, the multilayer film structure including the block copolymer film can be used as a substrate material for a PCB.

[0155] Fig.18 An integrated circuit (IC) package 1868 for an IC die 1881 including a multi-layer film structure and / or a metamaterial 1870 according to an exemplary embodiment 1800 embodying one or more aspects of the present disclosure is shown. Fig.18 As shown, the multilayer film structure and / or metamaterial 1870 may be configured to provide one or more of an electrical conductor / interconnect 1872 , a waveguide 1874 , an EMI absorber 1876 , a thermal interface material (TIM) 1878 , and a dielectric 1880 .

[0156] The multilayer film structure and / or metamaterial 1870 may be configured to manipulate energy or electromagnetic radiation, etc. The multilayer film structure and / or metamaterial IC package may be a selectively functional structure, such as part EMI shield, part TIM, part EMI absorber, part waveguide and / or part electrical conductor, etc. The multilayer film structure and / or metamaterial 1870 may be configured to provide a 3D structure (e.g., IC package substrate, etc.) that includes interconnects and / or vertical and multi-level as waveguides or coaxial structures, etc. Fig.18 In the illustrated embodiment, IC package 1868 includes four layers 1802 , 1804 , 1806 , 1808 , although other exemplary embodiments may include IC packages having more or less than four layers.

[0157] Fig. 20 A metamaterial TIM 2085 positioned within a device (eg, a smartphone, etc.) according to an exemplary embodiment 2000 embodying one or more aspects of the present disclosure is shown. Fig. 20 As shown, the metamaterial TIM 2085 is positioned between (e.g., compressively sandwiched between, etc.) an external device housing / heat sink 2086 and a PCB 2062 including an array 2087 of antenna elements 2088. In this exemplary embodiment, the metamaterial TIM 2085 is configured to be operable to provide a thermally conductive heat path substantially between the PCB 2062 and the external device housing / heat sink 2086. As indicated by the arrows, the metamaterial TIM 2085 is also configured to be operable to direct or manipulate signals (e.g., millimeter wave signals, etc.) from the antenna elements 2088 toward a reflector 2089. The reflector 2089 can then reflect the signals upward, thereby avoiding the problem of high dielectric constant effects on antenna performance.

[0158] Metamaterial patterning (e.g., FSS, etc.) can be used in a device housing or enclosure to direct signals for EMI reduction and for eliminating or reducing side lobes. As an example, a metamaterial FSS can be used inside a radome, which can allow for a reduction in radome thickness (e.g., from about 3 mm to 1 / 2 mm, etc.).

[0159] Fig.21A and Fig. 21B The exemplary embodiments shown in the drawings include a method for implementing one or more aspects of the present disclosure. FIG. 2A to FIG. 2E An example flexible material 2100 of a filled dielectric pyramid structure prepared by the process shown. The filled dielectric may include polydimethylsiloxane (PDMS) filled with carbon black, a filled block copolymer system, a filled elastic system, a filled thermoplastic system, etc. As disclosed herein, the pyramid structure may include a four-sided pyramid configured to be operable for EMI mitigation.

[0160] like Fig. 21BAs shown, the material 2100 having filled dielectric pyramid structures can be sufficiently flexible and conformable to be wrapped around a component, device, etc. Thus, the flexible material 2100 can include a functional (e.g., EMI mitigation, etc.) wrap 2 that can be wrapped around at least a portion of a PCB (e.g., wrapped around both sides, etc.).

[0161] Traditional board-level shields operate to contain EMI energy by creating a conductive metal Faraday cage around device components. Metal shields are often also used to contain thermal energy beneath them, which must be released, making EMI reduction and heat transfer cross-operations. Traditional board-level shields have a rectangular configuration of conductive metal with five sides. The sixth side of the Faraday shield is provided by the ground plane of the PCB.

[0162] In the exemplary embodiments disclosed herein, one (or more) metal sidewalls of the BLS are replaced by an absorber material. As an example, the absorber material may include one or more multilayer film structures and / or patterned materials disclosed herein, such as a multilayer film structure including a block copolymer film having domains (e.g., Figure 3 and Figure 4 etc.), FSS structures including FSS elements (e.g., Figure 6 and Fig.19 etc.), materials with pyramidal and / or non-pyramidal structures (e.g. Figures 1A to 1E , FIG. 2A to FIG. 2E , Figures 5 to 15 and Fig.21A , Fig. 21B wait).

[0163] By controlling the absorber thickness and placement, a high impedance wall can be created that will block or prevent electromagnetic energy from passing through the absorber. Typically, this can be frequency specific. The absorber material can include a thermally conductive absorber material to facilitate heat transfer in a hybrid EMI / thermal device.

[0164] In an exemplary embodiment, one or more BLS sidewalls may be made of an absorber material configured to direct or steer different frequencies in different directions such that some frequencies may be attenuated while remaining frequencies may not be attenuated.

[0165] Fig. 22 A board level shield (BLS) 2254 according to an exemplary embodiment 2200 that embodies one or more aspects of the present disclosure is shown. The BLS 2254 includes a top 2256 and four side walls. The BLS top 2256 and three side walls 2258 are made of a conductive metal (e.g., a metal sheet, etc.). The fourth side wall 2259 is made of an absorber material 2290 instead of the conductive metal used for the BLS top 2256 and the three other side walls 2258.

[0166] The fourth sidewall 2259 may be made of a thermally conductive absorber material 2290 such that the fourth sidewall is thermally conductive. In this case, the fourth sidewall 2259 may operate to absorb EMI while also allowing heat transfer. The sidewalls 2258 and 2259 may be configured (e.g., include mounting feet, etc.) for mounting (e.g., soldering, etc.) to the PCT 2262 or other substrate.

[0167] Fig.23 It is shown Fig. 22 Graph of simulated reduction in total radiated power (decibels (dB)) versus frequency (gigahertz (GHz)) for a board level shield in FIG. 5 , where the position of the absorber is different in two cases as the frequency shift of maximum total radiated power reduction occurs.

[0168] Exemplary embodiments may include laser curing of a dopant catalyst (e.g., spots, etc.) within the film to crystallize the dopant, thereby providing enhanced properties such as thermal management, electromagnetic interference (EMI) mitigation, electrical conductivity, thermal conductivity, EMI absorption, magnetic, dielectric and / or structural properties, etc. Other exemplary embodiments may include tape casting of inkjet printing of materials into openings (e.g., perforations, cuts, holes, etc.) in the film to provide electrical interconnects and / or thermal pathways.

[0169] Exemplary embodiments may include methods of providing EMI mitigation (e.g., EMI shielding, EMI absorption, etc.) and / or thermal management using at least one of a shape (e.g., a sheet, other extensions or protrusions, etc.), one or more domains of a multilayer block copolymer film structure, doping, and / or patterning. The shape may include a pyramidal structure (e.g., a four-sided pyramid, etc.) and / or a non-pyramidal structure.

[0170] In an exemplary embodiment, a method of preparing a multilayer thermal management and / or electromagnetic interference (EMI) mitigation material may include creating a block copolymer film having domains by adding one or more fillers or additives to modify one or more properties, characteristics, functions and / or performance of the domains (e.g., thermal management, electromagnetic interference (EMI) mitigation, electrical conductivity, thermal conductivity, EMI absorption, magnetic, dielectric and / or structural properties, etc.).

[0171] In an exemplary embodiment, a method of manufacturing a film may include: determining a functional pattern; selecting a first polymer having a first property; selecting a second polymer having a second property; selecting a functional material (e.g., predefined, predetermined form, etc.) having a third property (e.g., thermal conductivity, electrical conductivity, EMI absorption, dielectric, structure, etc.); and using the first and second polymers and the functional material to prepare a film via a block copolymer process so that the film has a functional pattern when assembled together (e.g., stacked and laminated into a multilayer structure, etc.). The functional pattern may include the height of the column, the width of the column, the spacing of the column, the loadability of the filler and / or the density of the filler in the column, etc.

[0172] In an exemplary embodiment, the multilayer structure includes a base layer that includes (e.g., is formed with, etc.) structures (e.g., pyramidal structures, non-pyramidal structures, etc.) protruding from the base layer along at least a first side of the base layer. A planarization layer is along the first side that provides a substantially planar surface opposite to a second side of the base layer.

[0173] The planarization layer may include dielectric materials (e.g., gradient dielectrics for impedance matching, uniform dielectric planarization layers, etc.), thermally conductive materials, electrically conductive materials, etc. At least one membrane layer may be disposed along (e.g., attached to, etc.) the planarization layer opposite the base layer.

[0174] The multilayer structure may include a frequency selective surface (FSS) element (e.g., a conductive ring, etc.) disposed generally between the film layer and the planarization layer. For example, the FSS element may include a conductive ring in a pattern. The multilayer structure may include multiple FSS layers or films (e.g., in a stacked arrangement, etc.) including FSS elements, such as conductive rings printed along or embedded within multiple layers or films. FSS elements of one layer may overlap FSS elements in another layer. FSS elements may include a base layer including EMI absorbing material.

[0175] In an exemplary embodiment, regions of increased or decreased magnetic properties may be created within a multilayer film structure and / or patterned material. For example, regions of magnetic attraction and repulsion may be used when a loaded copolymer resin is polymerized into a film during extrusion or calendaring.

[0176] In exemplary embodiments where thermal interface materials may be applied to and / or used in conjunction with multilayer film structures and / or patterned materials, a wide variety of thermal interface materials may be used. Example thermal interface materials include thermal gap fillers, thermal phase change materials, thermally conductive EMI absorbers or hybrid thermal / EMI absorbers, thermally conductive grease, thermally conductive paste, thermally conductive putty, dispensable thermal interface materials, thermally conductive pads, and the like.

[0177] In exemplary embodiments including or involving board-level shields, a wide variety of materials may be used for the board-level shields (broadly, shields) or portions thereof, such as cold-rolled steel, nickel-silver alloys, copper-nickel alloys, stainless steel, tin-plated cold-rolled steel, tin-plated copper alloys, carbon steel, brass, copper, aluminum, copper-beryllium alloys, phosphor bronze, steel, alloys thereof, plastic materials coated with conductive materials, or any other suitable conductive and / or magnetic materials. The materials disclosed in this application are provided herein for illustration only, as different materials may be used, for example, depending on the specific application.

[0178] Exemplary embodiments may include multilayer film structures and / or patterned materials that include at least a portion (e.g., a full thickness domain of a block copolymer film, etc.) having a high thermal conductivity (e.g., in the range of about 1 W / mK (watts per meter per calvin) to about 6 W / mK, etc.), depending on the specific materials used to prepare the multilayer film and / or patterned material and the loading percentage of the thermally conductive filler (if any). These thermal conductivities are merely examples, as other embodiments may include multilayer films and / or patterned materials that include at least a portion having a thermal conductivity greater than 6 W / mK, less than 1 W / mK, or between 1 W / mK and 6 W / mK.

[0179] In an exemplary embodiment, at least a portion of the multilayer film structure and / or patterned material may be heat-conductive (e.g., the heat-conductive domain of a block copolymer film, etc.), with a relatively high thermal conductivity. In these embodiments, the heat-conductive portion of the multilayer film structure and / or patterned material may be used to define or provide a portion of a heat-conductive path from a heat source to a heat removal / heat dissipation structure or component. The heat-conductive portion of the multilayer film structure and / or patterned material may be used, for example, to help conduct heat energy (e.g., heat, etc.) away from the heat source of an electronic device. The heat-conductive portion of the multilayer film structure and / or patterned material may be generally positioned between a heat source and a heat removal / heat dissipation structure or component to establish a thermal joint, interface, passage or heat-conductive path, along which heat may be transferred (e.g., conducted) from a heat source to a heat removal / heat dissipation structure or component. During operation, the heat-conductive portion of the multilayer film structure and / or patterned material may be used to allow heat to be transferred (e.g., conducted heat, etc.) from a heat source to a heat removal / heat dissipation structure or component along a heat-conductive path. In exemplary embodiments where the multilayer film structure and / or patterned material includes at least a portion for EMI mitigation (e.g., conductive and / or EMI absorbing domains of a block copolymer film, etc.), the multilayer film structure and / or patterned material may also be operable to mitigate EMI (e.g., absorb, block, reflect, etc.) incident on the EMI mitigation portion of the multilayer film structure and / or patterned material.

[0180] The example embodiments disclosed herein may be used with a wide range of heat sources, electronic devices (e.g., smart phones, etc.), and / or heat removal / dissipation structures or components (e.g., heat sinks, heat pipes, vapor chambers, device external housings or shells, etc.). For example, a heat source may include one or more heat generating components or devices (e.g., a CPU, a wafer in an underfill, a semiconductor device, a flip chip device, a graphics processing unit (GPU), a digital signal processor (DSP), a multiprocessor system, an integrated circuit (IC), a multi-core processor, etc.). In general, a heat source may include any component or device that has a temperature higher than a thermally conductive portion of a multilayer film structure and / or patterned material or that provides or transfers heat to a thermally conductive portion of a multilayer film structure and / or patterned material, regardless of whether the heat is generated by the heat source or is merely transferred through or via the heat source. Therefore, aspects of the present disclosure should not be limited to use with any single type of heat source, electronic device, heat removal / dissipation structure, etc.

[0181] In an exemplary embodiment, the EMI absorbing structure or EMI absorber may be outside or along the outside of the cavity or chamber. The EMI absorber or structure may be configured (e.g., shaped with a cone or pyramid, etc.) to suppress or reduce the likelihood of incident radiation (e.g., high frequency radiation at wide angles, radiation at stray frequencies, etc.) being reflected into the cavity or chamber through an aperture (e.g., an automotive radar aperture, etc.). Thus, the EMI absorber placement may allow for performance improvements and removal of stray frequencies for electronic devices (e.g., ADVICS (Advanced Intelligent Chassis System), etc.) within the cavity or chamber.

[0182] Fig.24 An exemplary device component 2400 embodying one or more aspects of the present disclosure and structures 2404 (eg, EMI absorbing pyramid structures, etc.) along the outside of the device component 2400 are shown. The structures 2404 are configured for EMI mitigation (eg, absorbing high frequency EMI, etc.).

[0183] The structures 2404 can be disposed along (e.g., attached to, etc.) and protrude outwardly from one or more exterior portions of the device component 2400. In the illustrated embodiment, the structures 2404 are disposed along the exterior or outer surface of the top wall or portion 2408 of the device. The structures 2404 are also disposed along the exterior or outer surface of the sides or sidewalls 2412 of the device.

[0184] Device component 2400 may define an interior, cavity, or chamber 2416 and an aperture or opening 2420 (e.g., an automotive radar aperture, a non-automotive radar aperture, other radar aperture, etc.) into chamber 2416. In the illustrated embodiment, structure 2404 is disposed along and / or defines the entire top surface 2408 of device component 2400, which in turn defines aperture 2420 into chamber 2416. Thus, structure 2404 is disposed around the entire perimeter of aperture 2420. In alternative embodiments, EMI absorbing structures may also be disposed along one or more interior surfaces of the device component within chamber 2416. In these alternative embodiments, EMI absorbing structures 2404 (e.g., pyramidal structures, etc.) may be disposed along both the interior and exterior surfaces of device component 2400 such that the EMI absorbing structures protrude inwardly and outwardly in opposite directions relative to device component 2400.

[0185] Device component 2400 may include an electronic device housing, a board level shield (BLS), other device components, etc. Device component 2400 may be configured (e.g., made of metal, shaped, sized, etc.) to mitigate (e.g., block, reflect, etc.) low frequency EMI. Structure 2404 may be configured (e.g., made of EMI absorbing material, shaped, sized, etc.) to mitigate (e.g., absorb, etc.) high frequency EMI.

[0186] Placing structure 2404 along the outside of device component 2400 can reduce the likelihood that incident radiation will reflect through aperture 2420 into interior, chamber or cavity 2416. Structure 2404 can operate to inhibit or prevent incident radiation from reflecting through aperture 2420 into cavity or chamber 2416.

[0187] As an example, structure 2404 may be configured to be operable to suppress high frequency radiation at wide angles from reaching aperture 2420. Placement of EMI absorbing structure 2404 may allow for improved performance of electronic devices (e.g., ADVICS (Advanced Intelligent Chassis System), etc.) within cavity or chamber 2416 and removal of radiation at stray frequencies.

[0188] EMI absorbing structure 2404 may include a quadrangular pyramid (eg, Fig.25The rectangular bases of adjacent pyramids may contact each other without substantially any gaps or spacing distances between the rectangular bases. This helps to avoid reflectivity that may occur if there are gaps between the rectangular bases of the pyramid structures. Other exemplary embodiments may include non-pyramid structures that taper or decrease in width (e.g., curve generally smoothly, etc.) from the top (e.g., from a point, etc.) toward the base. Alternative exemplary embodiments may include structures with non-rectangular bases (e.g., hexagonal bases, triangular bases, etc.). Therefore, the present disclosure should not be limited to only quadrangular pyramid structures, as other exemplary embodiments may include structures with different three-dimensional geometric shapes.

[0189] In an exemplary embodiment, the side of the structure 2404 may not be completely smooth or define a perfect straight line from top to bottom. For example, when viewed at a high magnification, the side may appear to have a stepped configuration. However, the side of the pyramidal or non-pyramid structure may preferably be relatively smooth (e.g., without any significant steps of any size, etc.) to reduce or avoid reflections of EMI incident on the structure. In addition, the structure may be configured to have a varying slope or taper along the side (e.g., at least two or more slopes, etc.). For example, a pyramidal structure may have a relatively gentle taper from the base toward the middle portion, a more rapid taper from the middle portion toward the top, and then a smaller taper from there to the top of the structure.

[0190] The structures 2404, 2504 may include a filled dielectric, such as polydimethylsiloxane (PDMS) filled with carbon black, another filled block copolymer system, a filled elastomeric system, a filled thermoplastic system, an injection moldable resin filled with carbon nanotubes, a polymer resin filled with carbon nanotubes, etc. Alternatively, the structures 2404, 2504 may be made of other materials and / or by other suitable processes (e.g., stepwise deposition of materials onto a functional carrier film, etc.).

[0191] In an exemplary embodiment, the configuration (e.g., height, shape, position, etc.) of structures 2404 may be non-randomized or randomized (e.g., via a computer randomization process, etc.). Randomizing the height of structures 2404 along the outside of device component 2400 may help reduce or avoid cavity resonances beneath a device housing that houses device component 2400. An exemplary embodiment may include quadrangular pyramid structures having bases of the same size, but one or more quadrangular pyramid structures may have a different height than one or more other quadrangular pyramid structures.

[0192] Structures having different heights can be used to accommodate height variations of shorter and taller adjacent components. For example, taller and shorter structures can be positioned relative to device component 2400 so that when device component 2400 is installed within an electronic device, taller and shorter structures 2404 are aligned with the shorter and taller components, respectively. The different heights of the structures can help avoid or reduce cavity resonances within a device housing that houses device component 2400.

[0193] The pyramid structure may include air-filled particles (e.g., air-filled microballoons, air-filled microbubbles, air-filled microspheres, etc.) for controllably reducing the dielectric constant of the pyramid structure. The air-filled particles add air to the pyramid structure, which reduces the dielectric constant (e.g., approximating foam, approaching foam properties, etc.).

[0194] Fig.25 A pyramid structure 2504 for an EMI absorber (e.g., EMI absorber 2404, etc.) according to an exemplary embodiment that embodies one or more aspects of the present disclosure is shown. By way of example only, the pyramid structure 2504 may have parameters such as a flat base of approximately 2.5 millimeters (mm) thick, a wedge thickness of approximately 2 mm, a wedge or pyramid height of approximately 3 mm, a truncated top of the pyramid of approximately 0.5 mm, a valley height of 0.5 mm, and a dielectric constant of n to j3.3. In this example, the pyramid height is 3 mm, but the base of the pyramid 2504 is located within the flat base at a distance below the top of the "valley height (i.e., 0.5 mm)". This is done to control the "valley" during modeling. A value of 0 for the "valley height" would place the base of the pyramid at the same location as the top of the flat base. The top of the pyramid is truncated by a value equal to the "truncation" (0.5 mm). For a value of 0 for the "truncation", the pyramid would reach a point at the "wedge height" value (3 mm). Although better electronic performance may be obtained if the "truncations" and "valley heights" are zero, thereby forming sharp pyramids and sharp valleys, non-zero values ​​for the "truncations" and "valley heights" may be based on manufacturing capabilities.

[0195] In an exemplary embodiment, a composition for an electromagnetic interference (EMI) absorber includes carbon nanotubes that are substantially cylindrical and have different inner diameters and / or different outer diameters.

[0196] In an exemplary embodiment, the carbon nanotubes include multi-walled carbon nanotubes that are hollow, generally cylindrical, and tubular. At least one multi-walled carbon nanotube has an inner diameter and an outer diameter that are different from the inner diameter and outer diameter of at least one other multi-walled carbon nanotube, respectively.

[0197] In an exemplary embodiment, the carbon nanotubes include multi-walled carbon nanotubes. At least one multi-walled carbon nanotube has a wall number that is different from the wall number of at least one other multi-walled carbon nanotube.

[0198] In an exemplary embodiment, the carbon nanotubes are generally cylindrical and have both different inner diameters and different outer diameters.

[0199] In an exemplary embodiment, the carbon nanotubes include multi-walled carbon nanotubes. The carbon nanotubes may also include single-walled carbon nanotubes and / or carbon nanostructures including a branched network of cross-linked carbon nanotube structures.

[0200] In an exemplary embodiment, the carbon nanotubes are located within an injection moldable resin. The composition may further include carbon black located within the injection moldable resin.

[0201] In an exemplary embodiment, the carbon nanotubes are located in a resin including one or more of the following: liquid silicone, urethane, polycarbonate, polyamide, polyester, polyolefin, polybutylene terephthalate, polypropylene, thermoplastic vulcanizate, thermoplastic elastomer, nylon and / or a mixture including polyolefin.

[0202] In an exemplary embodiment, the carbon nanotubes are located in a resin including polypropylene and Santoprene thermoplastic vulcanizate. For example, the composition can include about 10 volume % or less of Santoprene thermoplastic vulcanizate, about 89 volume % or more of polypropylene, and about 0.3 volume % or less of carbon nanotubes.

[0203] In an exemplary embodiment, the composition includes less than about 2 wt % carbon nanotubes.

[0204] In an exemplary embodiment, the composition further comprises one or more fillers and / or additives, including one or more pigments, plasticizers, processing aids, flame retardants, extenders, tackifiers, EMI absorbers, conductive fillers and / or magnetic particles.

[0205] In an exemplary embodiment, an automotive part is injection molded from the composition disclosed herein such that the automotive part has an integral, one-piece construction.

[0206] In an exemplary embodiment, a thermal management and EMI mitigation material includes the composition disclosed herein and is configured to be multifunctional, having a first function of EMI mitigation and a second function of thermal management.

[0207] In an exemplary embodiment, an electromagnetic interference (EMI) absorber includes one or more EMI absorbing structures. The one or more EMI absorbing structures include carbon nanotubes that are generally cylindrical and have different inner diameters and / or different outer diameters.

[0208] In an exemplary embodiment of the EMI absorber, the carbon nanotubes include multi-walled carbon nanotubes that are hollow, generally cylindrical and tubular. At least one multi-walled carbon nanotube has an inner diameter and an outer diameter that are different from the inner diameter and outer diameter of at least one other multi-walled carbon nanotube, respectively.

[0209] In an exemplary embodiment of the EMI absorber, the carbon nanotubes include multi-walled carbon nanotubes. At least one multi-walled carbon nanotube has a wall number that is different from the wall number of at least one other multi-walled carbon nanotube.

[0210] In an exemplary embodiment of an EMI absorber, the carbon nanotubes are generally cylindrical and have both different inner diameters and different outer diameters.

[0211] In an exemplary embodiment of the EMI absorber, the carbon nanotubes include multi-walled carbon nanotubes. The carbon nanotubes may also include single-walled carbon nanotubes and / or carbon nanostructures including a branched network of cross-linked carbon nanotube structures.

[0212] In an exemplary embodiment of the EMI absorber, one or more EMI absorbing structures include less than about 2 weight percent carbon nanotubes. The EMI absorber is configured to operate with a reflection loss greater than 15 decibels at a frequency from about 40 gigahertz (GHz) to about 120 GHz and / or from about 60 GHz to about 90 GHz and / or from about 70 GHz to about 85 GHz; and / or the EMI absorber is configured to operate with a reflection loss greater than 15 decibels at a frequency of about 77 GHz.

[0213] In an exemplary embodiment of the EMI absorber, the carbon nanotubes are located in a resin including one or more of the following: liquid silicone, urethane, polycarbonate, polyamide, polyester, polyolefin, polybutylene terephthalate, polypropylene, thermoplastic vulcanizate, thermoplastic elastomer, nylon and / or a mixture including polyolefins.

[0214] In an exemplary embodiment of the EMI absorber, the carbon nanotubes are located in a resin including polypropylene and Santoprene thermoplastic vulcanizate. For example, the EMI absorber may include less than about 10% by volume of Santoprene thermoplastic vulcanizate, more than about 89% by volume of polypropylene, and less than about 0.3% by volume of carbon nanotubes.

[0215] In an exemplary embodiment of the EMI absorber, one or more EMI absorbing structures include a pattern of quadrangular pyramid structures, wherein the quadrangular pyramid structures include rectangular bases, and the rectangular bases are configured such that the rectangular bases of adjacent quadrangular pyramid structures are in contact with each other without substantially any gaps or spacing distances between the rectangular bases of adjacent quadrangular pyramid structures.

[0216] In an exemplary embodiment of an EMI absorber, a low dielectric loss, low dielectric constant material is disposed over one or more EMI absorbing structures. The low dielectric loss, low dielectric constant material defines a planarization layer having a reverse pattern that is interlaced with the one or more EMI absorbing structures such that the one or more EMI absorbing structures and the planarization layer collectively have a substantially planar configuration and / or such that the planarization layer defines a planar surface over the one or more EMI absorbing structures.

[0217] Example embodiments are provided so that the present disclosure will be thorough, and the scope will be fully conveyed to those skilled in the art. A large number of specific details, such as examples of specific parts, devices, and methods, are set forth to provide a thorough understanding of the embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be adopted, the example embodiments can be implemented in many different forms, and no content should be interpreted as limiting the scope of the present disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail. In addition, the advantages and improvements that can be achieved with one or more exemplary embodiments of the present invention are provided only for illustrative purposes, and do not limit the scope of the present disclosure (because the exemplary embodiments disclosed herein can provide all or none of the above-mentioned advantages and improvements, and still fall within the scope of the present disclosure).

[0218] The specific dimensions, specific materials and / or specific shapes disclosed herein are examples in nature, and do not limit the scope of the present disclosure. The disclosure of the specific value and specific value range for a given parameter here is not the exhaustion of other values ​​and value ranges that can be used for one or more of the examples disclosed here. Moreover, it is envisioned that any two specific values ​​for the specific parameters narrated here can limit the endpoints of the value range that can be suitable for the given parameter (that is, the disclosure of the first value and the second value for a given parameter can be interpreted as disclosure that can also adopt any value between the first and second values ​​for a given parameter). For example, if parameter X is exemplified as having value A and also exemplified as having value Z here, it is envisioned that parameter X can have a value range from about A to about Z. Similarly, it is envisioned that the disclosure of two or more value ranges (regardless of whether such ranges are nested, overlapped or different) for a parameter includes all possible combinations of the value ranges that can be clamped using the endpoints of the disclosed range. For example, if parameter X is illustrated herein as having values ​​within the range 1-10 or 2-9 or 3-8, it is also contemplated that parameter X may have other value ranges including 1-9, 1-8, 1-3, 1-2, 2-10, 2-8, 2-3, 3-10, and 3-9.

[0219] The terms used herein are only for the purpose of describing specific example embodiments and are not intended to be limiting. As used herein, the singular forms "one" and "an" may be intended to also include plural forms, unless the context clearly indicates otherwise. The terms "including" and "having" are inclusive, and therefore specify the presence of the described features, integers, steps, operations, elements and / or parts, but do not exclude the presence or increase of one or more other features, integers, steps, operations, elements, parts and / or their groups. The method steps, processes and operations described herein are not to be interpreted as necessarily requiring their execution in the particular order discussed or illustrated, unless specifically identified as an execution order. It is also to be understood that additional or alternative steps may be adopted.

[0220] When an element or layer is referred to as being "on," "engaged," "connected," or "coupled" to another element or layer, the element or layer may be directly on, directly engaged, connected, or coupled to another element or layer, or intervening elements or layers may be present. Conversely, when an element is referred to as being "directly on," "directly engaged," "directly connected," or "directly coupled" to another element or layer, no intervening elements or layers may be present. Other words used to describe relationships between elements should be interpreted in the same manner (e.g., "between" versus "directly between," "adjacent" versus "directly adjacent," etc.). As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0221] The term "approximately" when applied to a value indicates that the calculation or measurement allows for slight imprecision in the value (close to exact in value; approximately or reasonably close to a value; nearly). If for some reason the imprecision provided by "approximately" is not otherwise understood in the art in this ordinary sense, then "approximately" as used herein indicates at least the variation that may result from ordinary measurement methods or use of such parameters. For example, the terms "substantially," "about," and "roughly" may be used herein to mean within manufacturing tolerances. Whether or not modified by the term "approximately," the claims include equivalents to the quantities.

[0222] Although the terms first, second, third, etc. can be used to describe various elements, components, regions, layers and / or parts here, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms can only be used to distinguish an element, component, region, layer or part from another region, layer or part. Terms such as "first", "second" and other numerical terms do not imply order when used here, unless the context clearly indicates. Thus, the first element, component, region, layer or part discussed below can be referred to as the second element, component, region, layer or part without departing from the teaching of the example embodiments.

[0223] Spatially relative terms (such as "inside", "outside", "below", "below", "down", "above", "upper", etc.) can be used here for ease of description to describe the relationship of one element or feature to another element or feature as illustrated in the drawings. Spatially relative terms may be intended to include different orientations of the device in use or operation in addition to the orientations depicted in the drawings. For example, if the device in the drawings is flipped, the elements described as "below" or "below" other elements or features will be oriented to be "above" other elements or features. Thus, the example term "below" can include both the above and below orientations. The device can be oriented in other ways (rotated 90 degrees or in other orientations), so the spatially relative descriptors used here are interpreted.

[0224] The foregoing description of the embodiments has been provided for the purpose of illustration and description. It is not intended to be exhaustive or to limit the present disclosure. The independent elements, intended or described uses or features of a particular embodiment are generally not limited to that particular embodiment, but are interchangeable where appropriate and can be used in a selected embodiment (even if the embodiment is not specifically shown or described). The same content can also be changed in many ways. Such changes are not considered to be deviations from the present disclosure, and all such modifications are intended to be included within the scope of the present disclosure.

Claims

1. A composition for an electromagnetic interference (EMI) absorber, the composition comprising substantially cylindrical carbon nanotubes having different inner diameters and / or different outer diameters.

2. The composition according to claim 1, in, The carbon nanotubes include multi-walled carbon nanotubes that are hollow, generally cylindrical and tubular, and wherein at least one of the multi-walled carbon nanotubes has an inner diameter and an outer diameter that are different from the inner diameter and outer diameter of at least one other of the multi-walled carbon nanotubes, respectively.

3. The composition according to claim 1, in, The carbon nanotubes include multi-walled carbon nanotubes, and wherein at least one of the multi-walled carbon nanotubes has a wall number that is different from a wall number of at least one other of the multi-walled carbon nanotubes.

4. The composition according to claim 1, in, The carbon nanotubes are generally cylindrical and have both different inner diameters and different outer diameters.

5. The composition according to claim 1, in, The carbon nanotubes include multi-walled carbon nanotubes.

6. The composition according to claim 5, in, The carbon nanotubes also include single-walled carbon nanotubes and / or carbon nanostructures comprising a branched network of cross-linked carbon nanotube structures.

7. The composition according to any one of claims 1 to 6, in, The carbon nanotubes are located within an injection moldable resin.

8. The composition according to claim 7, in, The composition also includes carbon black within the injection moldable resin.

9. The composition according to any one of claims 1 to 6, in, The carbon nanotubes are located in a resin comprising one or more of the following: liquid silicone, urethane, polycarbonate, polyamide, polyester, polyolefin, polybutylene terephthalate, polypropylene, thermoplastic vulcanizate, thermoplastic elastomer, nylon, and / or a mixture including polyolefin.

10. The composition according to any one of claims 1 to 6, in, The carbon nanotubes are located within a resin including polypropylene and Santoprene thermoplastic vulcanizate.

11. The composition according to claim 10, in, The composition includes less than about 10% by volume of Santoprene thermoplastic vulcanizate, more than about 89% by volume of polypropylene, and less than about 0.3% by volume of carbon nanotubes.

12. The composition according to any one of claims 1 to 6, in, The composition includes less than about 2% by weight of carbon nanotubes.

13. The composition according to any one of claims 1 to 6, in, The composition also includes one or more fillers and / or additives, including one or more pigments, plasticizers, processing aids, flame retardants, extenders, tackifiers, EMI absorbers, conductive fillers and / or magnetic particles.

14. An EMI absorber comprising the composition according to any one of claims 1 to 6, in, The EMI absorber includes one or more EMI absorbing structures.

15. The EMI absorber according to claim 14, in, The one or more EMI absorbing structures include a pattern of quadrangular pyramid structures including rectangular bases configured such that the rectangular bases of adjacent quadrangular pyramid structures contact each other without substantially any gaps or spacing distances between the rectangular bases of adjacent quadrangular pyramid structures.

16. The EMI absorber of claim 14, further comprising a low dielectric loss, low dielectric constant material disposed over the one or more EMI absorbing structures, in, The low dielectric loss, low dielectric constant material defines a planarization layer having a reverse pattern, which is interlaced with the one or more EMI absorbing structures so that the one or more EMI absorbing structures and the planarization layer collectively have a substantially flat construction, and / or so that the planarization layer defines a flat surface located above the one or more EMI absorbing structures.

17. The EMI absorber according to claim 14, in: The EMI absorber is configured to operate with a reflection loss greater than 15 decibels at frequencies from about 40 gigahertz GHz to about 120 GHz and / or from about 60 GHz to about 90 GHz and / or from about 70 GHz to about 85 GHz; and / or The EMI absorber is configured to operate at a frequency of approximately 77 GHz with a reflection loss greater than 15 decibels.

18. An automobile part which is injection molded from the composition according to any one of claims 1 to 6 such that the automobile part has an integral one-piece construction.

19. A thermal management and EMI mitigation material, comprising the composition of any one of claims 1 to 6, and configured to be multifunctional, having a first function of EMI mitigation and a second function of thermal management.

20. An electromagnetic interference (EMI) absorber, comprising one or more EMI absorbing structures, wherein the one or more EMI absorbing structures comprise carbon nanotubes that are substantially cylindrical and have different inner diameters and / or different outer diameters.

21. The EMI absorber according to claim 20, in, The carbon nanotubes include multi-walled carbon nanotubes that are hollow, generally cylindrical and tubular, and wherein at least one of the multi-walled carbon nanotubes has an inner diameter and an outer diameter that are different from the inner diameter and outer diameter of at least one other of the multi-walled carbon nanotubes, respectively.

22. The EMI absorber according to claim 20, in, The carbon nanotubes include multi-walled carbon nanotubes, and wherein at least one of the multi-walled carbon nanotubes has a wall number that is different from a wall number of at least one other of the multi-walled carbon nanotubes.

23. The EMI absorber according to claim 20, in, The carbon nanotubes are generally cylindrical and have both different inner diameters and different outer diameters.

24. The EMI absorber according to claim 20, in, The carbon nanotubes include multi-walled carbon nanotubes.

25. The EMI absorber according to claim 24, in, The carbon nanotubes also include single-walled carbon nanotubes and / or carbon nanostructures comprising a branched network of cross-linked carbon nanotube structures.

26. The EMI absorber according to any one of claims 20 to 25, in, The one or more EMI absorbing structures include less than about 2 wt. % carbon nanotubes, and wherein: The EMI absorber is configured to operate with a reflection loss greater than 15 decibels at frequencies from about 40 gigahertz GHz to about 120 GHz and / or from about 60 GHz to about 90 GHz and / or from about 70 GHz to about 85 GHz; and / or The EMI absorber is configured to operate at a frequency of approximately 77 GHz with a reflection loss greater than 15 decibels.

27. The EMI absorber according to any one of claims 20 to 25, in, The carbon nanotubes are located in a resin comprising one or more of the following: liquid silicone, urethane, polycarbonate, polyamide, polyester, polyolefin, polybutylene terephthalate, polypropylene, thermoplastic vulcanizate, thermoplastic elastomer, nylon, and / or a mixture including polyolefin.

28. The EMI absorber according to any one of claims 20 to 25, in, The carbon nanotubes are located within a resin including polypropylene and Santoprene thermoplastic vulcanizate.

29. The EMI absorber according to claim 28, in, The EMI absorber includes less than about 10 volume percent of Santoprene thermoplastic vulcanizate, more than about 89 volume percent of polypropylene, and less than about 0.3 volume percent of carbon nanotubes.

30. The EMI absorber according to any one of claims 20 to 25, in, The one or more EMI absorbing structures include a pattern of quadrangular pyramid structures including rectangular bases configured such that the rectangular bases of adjacent quadrangular pyramid structures contact each other without substantially any gaps or spacing distances between the rectangular bases of adjacent quadrangular pyramid structures.

31. The EMI absorber of any one of claims 20 to 25, further comprising a low dielectric loss, low dielectric constant material disposed over the one or more EMI absorbing structures, in, The low dielectric loss, low dielectric constant material defines a planarization layer having a reverse pattern, which is interlaced with the one or more EMI absorbing structures so that the one or more EMI absorbing structures and the planarization layer collectively have a substantially flat construction, and / or so that the planarization layer defines a flat surface located above the one or more EMI absorbing structures.

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