SYSTEM AND METHOD FOR BONDING ELECTRONIC COMPONENTS ON SUBSTRATES HAVING ROUGH SURFACES - Patent application

Abstract

To provide electronic devices, methods, and textile products, for bonding electronic components on textile substrates such as fabric with rough surfaces.SOLUTION: A method for bonding an electronic component (e.g., in a packaged die form) to a substrate with a rough surface and / or incorporating an electronic device in a substrate of an item (e.g., a piece of clothing) comprises: disposing an insulating adhesive on a substrate 1000; applying heat and pressure to the insulating adhesive to cause the adhesive to flow into at least one opening formed in the substrate; curing the insulating adhesive to form a pad 1402 that is partially embedded in the substrate; disposing a trace 1400 on a planar smooth surface of the pad; depositing an anisotropic conductive material 1500 on the pad so as to cover the trace; placing the electronic component on the pad so that an electrical coupling is formed between the electronic component 1700 and the trace; and bonding the electronic component to the substrate by curing the anisotropic conductive material.SELECTED DRAWING: Figure 18

Description

Summary of the Invention [Problem to be solved by the invention]

[0001] The present disclosure generally relates to a system and method for bonding electronic components onto a substrate having a rough surface (e.g., a textile substrate such as a fabric). In the prior art, a chip is bonded to the fabric via conductive epoxy and wire bonding. A non-conductive adhesive is manually placed on the fabric. An electronic component is placed on the non-conductive adhesive with the conductive pads facing up so that the conductive pads are accessible. A first end of a wire is then bonded to a trace formed on the fabric via conductive epoxy. A second, opposing end of the wire is bonded to a conductive pad of the chip via conductive epoxy or wire bonding. The conductive epoxy is manually placed on the fabric and the chip. The wire connections often fail, thus resulting in undesirable yield and / or lifespan of the fabric electronics. This manual process is also relatively expensive and time consuming.

[0002] The present disclosure relates to implementing a system and method for bonding an electronic component (e.g., an integrated circuit) to a substrate having a rough surface (e.g., a textile substrate such as a woven fabric). The method includes disposing an insulating adhesive (e.g., an epoxy) on the substrate, applying heat and pressure to the insulating adhesive to cause the adhesive to flow into at least one opening formed in the substrate, curing the insulating adhesive to form a pad at least partially embedded in the substrate, the pad including an exposed flat smooth surface, disposing at least one trace on the flat smooth surface of the pad, depositing an anisotropic conductive material (e.g., an anisotropic conductive paste (ACP) or an anisotropic conductive film (ACF)) on the pad to at least cover the at least one trace, disposing the electronic component on the pad such that an electrical bond is formed between the electronic component and the at least one trace, and bonding the electronic component to the substrate by curing the anisotropic conductive material. The electronic component may be electrically coupled to the at least one trace at the same time that the electronic component is bonded to the substrate.

[0003] The pad is a rigid or semi-rigid structure having a size and shape selected such that the flexibility of the substrate is not affected by the pad. The flat smooth surface of the pad is free of any openings.

[0004] In some scenarios, the electronic components may be formed on a die of semiconductor material, the die being bonded to the substrate via the anisotropic conductive material. Alternatively, the electronic components are formed on a die of semiconductor material packaged as a chip, the chip being bonded to the substrate via the anisotropic conductive material.

[0005] In these or other scenarios, proper operation of the electronic device including the electronic component is verified prior to curing of the anisotropic conductive material. After being bonded to the substrate, the electronic component may be coated with a flexible, fluid-resistant material.

[0006] This document also relates to an electronic device. The electronic device includes a substrate (e.g., a textile substrate such as a woven fabric) having a rough surface, a pad (the pad being formed of a cured insulating adhesive (e.g., epoxy) at least partially embedded in the substrate) integrated with the substrate, at least one trace disposed on a flat smooth surface of the pad, an anisotropic conductive material deposited on the flat smooth surface of the pad to at least cover the at least one trace, and an electronic component bonded to the pad via the cured anisotropic conductive material. The anisotropic conductive material facilitates electrical coupling between the electronic component and the at least one trace.

[0007] In some scenarios, the pad is a rigid or semi-rigid structure with a size and shape selected such that the flexibility of the substrate is not affected by the pad. The flat smooth surface of the pad is free of any openings.

[0008] In these or other scenarios, the electronic components are formed on a die of semiconductor material. The die is bonded to a substrate via an anisotropic conductive material. Alternatively, the electronic components are formed on a die of semiconductor material packaged as a chip. The chip is bonded to a substrate via an anisotropic conductive material. Proper operation of the electronic device may be verified before the anisotropic conductive material is cured. The electronic components may be coated with a flexible, fluid-resistant material (e.g., a rubber or polymeric material). [Brief description of the drawings]

[0009] The present solution is described with reference to the following drawings, in which like numerals represent like items throughout:

[0010] [Figure 1] FIG. 1 provides a diagram of an exemplary system for bonding electronic components onto a substrate having a rough surface (e.g., a textile substrate).

[0011] [Diagram 2]FIG. 2 provides a diagram of an example architecture of the computing device shown in FIG.

[0012] [Diagram 3] FIG. 3 provides an illustration of an exemplary substrate.

[0013] [Figure 4] FIG. 4 provides a diagram of an exemplary chip that includes an integrated circuit.

[0014] [Diagram 5] FIG. 5 provides an illustration of an exemplary trace formed within a pad that is integral with and at least partially embedded in a substrate.

[0015] [Figure 6] FIG. 6 provides an illustration of another exemplary trace formed within a pad that is integral with and at least partially embedded in a substrate.

[0016] [Figure 7] FIG. 7 provides an illustration of an exemplary electronic device (eg, a radio frequency (RF) tag) integrated with a substrate.

[0017] [Figure 8] FIG. 8 provides an illustration of another exemplary electronic device (eg, a communication device and a power source) integrated with a substrate.

[0018] [Figure 9] FIG. 9 provides an exemplary flow diagram for bonding an electronic component (e.g., in packaged chip or die form) to a substrate having a rough surface and / or for incorporating an electronic device into the substrate of an article (e.g., a piece of clothing).

[0019] [Figure 10] FIG. 10 provides a diagram that is useful for understanding how substrate-based electronic devices are fabricated. [Figure 11]FIG. 11 provides a diagram useful for understanding how substrate-based electronic devices are fabricated. [Figure 12] FIG. 12 provides a diagram that is useful for understanding how substrate-based electronic devices are fabricated. [Figure 13] FIG. 13 provides a diagram that is useful for understanding how substrate-based electronic devices are fabricated. [Figure 14] FIG. 14 provides a diagram that is useful for understanding how substrate-based electronic devices are fabricated. [Figure 15] FIG. 15 provides a diagram that is useful for understanding how substrate-based electronic devices are fabricated. [Figure 16] FIG. 16 provides a diagram that is useful for understanding how substrate-based electronic devices are fabricated. [Figure 17] FIG. 17 provides a diagram that is useful for understanding how substrate-based electronic devices are fabricated. [Figure 18] FIG. 18 provides a diagram useful for understanding how substrate-based electronic devices are fabricated.

[0020] [Figure 19] FIG. 19 provides an illustration of an exemplary substrate-based electronic device that includes electronic components and traces disposed on and coupled to pads formed on a substrate having a rough surface.

[0021] [Figure 20] FIG. 20 provides an illustration of an exemplary pad formed on a substrate.

[0022] [Figure 21] FIG. 21 provides an illustration of an exemplary trace formed on a substrate.

[0023] [Figure 22]FIG. 22 provides a diagram of an exemplary electronic component bonded to the substrate shown in FIGS. 20-21 such that electrical coupling exists between the traces and conductive pads of the electronic component.

[0024] [Figure 23] FIG. 23 provides an illustration of an exemplary sensor bonded to a substrate in accordance with the present solution. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] It will be readily understood that the components of the embodiments as generally described herein and illustrated in the accompanying drawings could be arranged and designed in a wide variety of different configurations. Thus, the following more detailed description of various embodiments, as represented in the drawings, is not intended to limit the scope of the disclosure, but is merely representative of the various embodiments. While various aspects of the embodiments are presented in the drawings, the drawings are not necessarily drawn to scale unless specifically indicated.

[0026] The present solution may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the present solution is therefore indicated by the appended claims, rather than by this detailed description. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope.

[0027] Throughout this specification, references to features, advantages, or similar language do not imply that all of the features and advantages that may be realized in the solution should or are in any single embodiment of the solution. Rather, language referring to features and advantages is understood to mean that a particular feature, advantage, or characteristic that is described in connection with an embodiment is included in at least one embodiment of the solution. Thus, throughout this specification, discussions of features and advantages and similar language may, but do not necessarily, refer to the same embodiment.

[0028] Furthermore, the described features, advantages, and characteristics of the solution may be combined in any suitable manner in one or more embodiments. Those skilled in the art will recognize in light of the description herein that the solution can be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments of the solution.

[0029] Throughout this specification, reference to "one embodiment," "an embodiment," or similar language means that a particular feature, structure, or characteristic described in connection with the illustrated embodiment is included in at least one embodiment of the solution. Thus, throughout this specification, the phrases "in one embodiment," "in an embodiment," and similar language may, but do not necessarily, all refer to the same embodiment.

[0030] As used in this document, the singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. As used in this document, the term "comprising" means "including, but not limited to."

[0031] One of the challenges in fabricating textile electronics is to bond electronic components onto textiles. As mentioned above in the background section of this document, a known solution for creating textile electronic devices is to bond electronic components (e.g., integrated circuits) onto textile pieces using wires and two different types of epoxy. However, this known solution is difficult to scale into an automated fabrication process for textile electronics. This known approach requires the development of new chip packages. To solve this problem, the present solution provides a system and method for fabricating textile electronics by mounting packaged chips or bare dies onto a substrate in a novel way.

[0032] The present solution generally relates to a system and method for bonding electronic components onto a substrate having a rough surface (e.g., a textile substrate such as a fabric). The present solution utilizes an adhesive to create one or more smooth and flat surfaces on a portion of the substrate. Conductive traces are then formed on the substrate and / or the smooth / flat surface according to a printing technique. Electronic components (e.g., integrated circuits in packaged chip, chiplet or bare die form, batteries, and / or surface mounted passive components such as resistors or capacitors) are aligned with and mounted onto the conductive traces using a bonding process. As used herein, the term "chiplet" refers to a circuit block designed to cooperate with other circuit components to form a more complex circuit. Circuit blocks may include, but are not limited to, passive electronic components (e.g., resistors and / or capacitors). Bonding processes may include, but are not limited to, ACP bonding process and / or ACF bonding process.

[0033] Exemplary System

[0034] Referring now to FIG. 1, a schematic diagram of an exemplary system 100 for bonding electronic components onto a substrate having a rough surface (e.g., a textile substrate such as a fabric) is provided. The electronic components may include, but are not limited to, ICs, batteries, resistors, capacitors, inductors, diodes, and / or other active / passive elements. A diagram of an exemplary electronic component 400 is provided in FIG. 4. The electronic component 400 comprises a packaged chip having an integrated circuit. As shown in FIG. 1, the system 100 comprises a counter 104 on which the substrate 102 (e.g., a fabric) may be placed or otherwise positioned. The counter 104 may have a conveyor belt 126 or other means disposed thereon to mechanically move the substrate 102 in a direction 130.

[0035] A dispensing machine 116 may be provided for the substrate 102. The dispensing machine 116 is configured to receive a reel and / or spool and rotate the reel / spool in two opposite directions as indicated by arrows 132, 134. The rotation is accomplished using gears and motors. The substrate 102 is wound onto the reel / spool. The substrate 102 may be formed from cotton or a synthetic material.

[0036] The substrate 102 may include, but is not limited to, a woven fabric as shown in FIG. 3. In particular, the woven fabric includes a plurality of openings 300 that (i) make it difficult to form electrically isolated, high-resolution traces on the fabric, and (ii) make it difficult to surface mount an electronic component 400 or die on the fabric. Difficulty (i) exists because each trace formed on the fabric also has an opening aligned with the opening 300. Thus, the trace needs to have a relatively large surface area to account for the loss of material caused by the openings. In practice, two adjacent traces overlap or otherwise contact each other, thereby providing no electrical insulation between them. Difficulty (ii) exists because each contact pad 402 of the electronic component 400 or die (a) has a size that is the same or smaller than the size of each opening, and / or (b) a spacing between adjacent contact pads that is the same as the spacing of the openings 300. Thus, when a surface mounting process is employed, an incomplete electrical connection or no electrical connection may be formed between at least one contact pad and at least one trace. The present solution addresses these issues, and the manner in which these issues are addressed will become apparent as the discussion proceeds.

[0037] During the manufacturing process, the computing device 140 controls the dispensing machine 116 to rotate the reel / spool an amount that allows a portion of the substrate 102 to be unwound. The conveyor belt 126 then moves the unwound portion of the substrate 102 a particular amount in the direction 130. The conveyor belt 126 may also be controlled by the computing device 140. In some scenarios, the substrate 102 is moved in the direction 130 and / or the opposite direction 152 such that a given portion 142 of the substrate 102 is aligned with a given component 106, 108, 110, 112, 114, 118 of the manufacturing system 150 at a different time during the manufacturing process. In other scenarios, the manufacturing system 150 includes an alignment mechanism 138 that moves the components 106, 108, 110, 112, 114, 118 relative to a given portion 142 of the substrate 102 during the manufacturing process. The alignment mechanism 138 may include, but is not limited to, motors, gears, tracks, and / or articulated arms. The alignment mechanism 138 is also controlled by a computing device 140. The substrate 102 may have at least one alignment marking that may be used to guide the computing device 140 to properly align the components 106, 108, 110, 112, 114, 118 with a given portion 142 thereof. The alignment markings may include, but are not limited to, shapes or lines printed on the substrate created by and / or formed using a color die.

[0038] The pad is then integrated and at least partially embedded in the substrate 102. An illustration of an exemplary pad 500 is provided in FIG. 5. The pad 500 has a flat smooth continuous surface 502 and includes a material filling the opening 300 of the given portion 142 of the substrate 102. At this point, the adhesive applicator 106 is aligned with the given portion 142 of the substrate 102. The adhesive applicator includes a nozzle 124 for dispensing and applying adhesive to the given portion 142 of the substrate 102. Nozzles are well known in the art. The adhesive may include, but is not limited to, a one-part insulating epoxy, or a two-part insulating epoxy (e.g., having part number 2216 available from 3M in the United States). The amount of adhesive placed on the substrate 102 is selected according to a given application and / or the desired shape / size of the pad.

[0039] Heat and pressure are then applied to the adhesive and a given portion 142 of the substrate 102 within a given time (e.g., 1-20 minutes). At this point, a heat / pressure applicator 108 is aligned with the adhesive. Heat / pressure applicators are well known in the art. In some scenarios, the heat / pressure applicator 108 includes a press plate 122 that is movable in two opposing directions indicated by arrows 154. The press plate 122 may be coated with a non-stick material or have a non-stick film 136 bonded to it. The non-stick features of the press plate 122 ensure that the adhesive does not adhere or otherwise bond to the press plate while heat / pressure is applied thereto.

[0040] As the press plate 122 moves into contact with the substrate 102, the adhesive and the given portion 142 of the substrate are compressed between the press plate 122 and the counter 104 (or conveyor belt 126) for a given time (e.g., 1-3 minutes). The temperature of the press plate is raised (e.g., via conductive wires disposed within the press plate) to a given temperature (e.g., 150-160° C.) before, during, or after it moves into contact with the substrate 102. The application of heat and pressure causes the adhesive to flow into the openings 300 of the given portion 142 of the substrate 102 and harden such that the pad 500 becomes integral with the substrate. The pad 500 provides a flat, smooth, exposed, continuous surface (without any openings) upon which an electronic component (e.g., a chip or die) can be mounted on the given portion 142 of the substrate. The pad 500 is a rigid or semi-rigid structure. The shape and size of the pad is selected such that the flexibility of the substrate is not affected thereby, or is only minimally affected. The pad can have any shape, such as a circular, oval, square, or rectangular shape.

[0041] After the pads are formed, a trace printer 110 is used to place one or more conductive traces on the substrate 102. Trace printers are well known in the art. In some scenarios, the trace printer includes an inkjet printer configured to dispense a conductive ink whereby the traces are printed or otherwise deposited on the object (e.g., substrate 102). An illustration of a conductive trace 504 disposed on a substrate is provided in FIG. 5. In FIG. 5, the conductive trace 504 is shown as being disposed only on the pad 500. The present solution is not limited in this respect. The conductive trace can be disposed on the pad and / or other areas of the substrate where no pad is present as shown in FIG. 6. The conductive trace can have any geometric shape selected according to a given application. For example, as shown in FIGS. 7-8, an electronic device (e.g., a radio frequency identification (RFID) device) may include a conductive trace that forms an antenna structure 700, 800 (e.g., a dipole or coil) directly on a fabric 730, 830. Conductive traces continue to the pads 710, 810 for connection to the processor 720, 820. Conductive traces may additionally or alternatively be provided to form an electrical connector between an electronic component (e.g., chip / die) and the power source 802.

[0042] The printer 110 may also form at least one alignment marking 506 on the pad 500 that can be subsequently used to guide proper placement of an electronic component (e.g., chip / die) on the pad. Alignment markings may include, but are not limited to, shapes or lines printed on the pad or substrate (e.g., of a color different from the color of the pad or substrate), created by stitching (e.g., using a thread of a color different from the color of the pad or substrate), and / or formed using a die (e.g., a die having a color different from the color of the pad or substrate).

[0043] The electronic component 400 is then bonded to the pad 500. At this point, the anisotropic conductive material printer 112 is aligned with the pad 500. The printer 112 is configured to print or otherwise deposit an anisotropic conductive material onto the conductive traces and / or pads. Such printers are well known in the art. In some scenarios, the printer 112 includes an inkjet printer or an extrusion printer. The anisotropic conductive material may include, but is not limited to, anisotropic conductive paste (ACP) material or anisotropic conductive film (ACF) material. ACP and ACF materials are well known in the art. In some scenarios, the ACP and ACF materials include a thermosetting resin containing large graphite particles, gold particles, and gold-plated plastic particles. The anisotropic conductive material has a dual purpose: to create a vertical electrical connection between the traces and the conductive members (e.g., pads) of the electronic component (e.g., chip / die) and to securely bond the electronic component to the pads.

[0044] Once the anisotropic conductive material has been applied to the conductive traces printed on the substrate, the electronic component bonder 114 is aligned with a given portion 142 of the substrate 102. The electronic component bonder 114 includes mechanical means (e.g., an articulated arm) for aligning the electronic component with the traces and / or for placing the electronic component on the pads. The electronic component is strategically placed on the pads such that an electrical bond or connection is formed between the traces and the electronic component. Heat and / or pressure are then applied by the heat / pressure applicator 108 to form a conductive path between the traces and the electronic component and to cure the anisotropic conductive material. In effect, the electronic component is bonded to the substrate.

[0045] In some scenarios, proper operation of the electronic device may optionally be verified prior to application of heat / pressure to cure the anisotropic conductive material. Verification may be accomplished using an RFID tag reader and / or a transmitter of the computing device 140. If the electronic device is working properly, the anisotropic conductive material is cured. Conversely, if the electronic device is not working properly, the electronic component (e.g., chip / die) is removed from the pads and a new electronic component is placed on the pads.

[0046] In these or other scenarios, the electronic device may be coated with a flexible fluid-resistant material. The flexible fluid-resistant material may have a color that matches the color of the substrate 102. The applicator 106, the printer 110, and / or the printer 112 may be used to apply a coating of the flexible fluid-resistant material to the substrate 102.

[0047] The substrate 102 may then be cut by a cutting mechanism 118 to form a system with one or more integrated electronic devices (e.g., RFID tags). The systems may include, but are not limited to, medical patches with sensors and wireless communication devices, smart filters with sensors, bed sheets with sensors, sheet covers with sensors, foldable tents with antennas and solar transducers, and wearable items (e.g., shirts). The cutting mechanism 118 may include, but is not limited to, razors and / or scissors. Razors and scissors are well known in the art and therefore will not be described herein.

[0048] Referring now to Figure 2, a detailed block diagram of an exemplary architecture of a computing device 140 is provided. The computing device 140 may include more or less components than those shown in Figure 2. However, the components shown are sufficient to disclose an exemplary embodiment implementing the present solution. The hardware architecture of Figure 2 represents one embodiment of a representative computing device configured to facilitate fabrication of a substrate-based electronic device. As such, the computing device 140 of Figure 2 implements at least a portion of a method for bonding an electronic component (e.g., a chip) onto a substrate in accordance with the present solution.

[0049] Some or all of the components of computing device 140 may be implemented as hardware, software, and / or a combination of hardware and software. Hardware includes, but is not limited to, one or more electronic circuits. Electronic circuits may include, but are not limited to, passive components (e.g., resistors and capacitors) and / or active components (e.g., amplifiers and / or microprocessors). The passive and / or active components may be adapted, arranged, and / or programmed to perform one or more of the methodologies, procedures, or functions described herein.

[0050] 2, computing device 140 comprises a user interface 202, a CPU 206, a system bus 210, memory 212 connected to and accessible through other portions of computing device 140 via system bus 210, and hardware entities 214 connected to system bus 210. The user interface may include input devices (e.g., a keypad 250) and output devices (e.g., a speaker 252, a display 254, and / or light emitting diodes 256) to facilitate user software interaction to control the operation of computing device 140.

[0051] At least some of the hardware entities 214 perform actions involving access to and use of memory 212, which may be RAM, a disk drive, and / or a compact disk read only memory ("CD-ROM"). The hardware entities 214 may include a disk drive unit 216 with a computer-readable storage medium 218 that stores one or more sets of instructions 220 (e.g., software code) configured to implement one or more of the methodologies, procedures, or functions described herein. The instructions 220 may also reside completely or at least partially within the memory 212 and / or within the CPU 206 during its execution by the computing device 140. The memory 212 and the CPU 206 may also constitute a machine-readable medium. As used herein, the term "machine-readable medium" refers to a single medium or multiple media (e.g., a centralized or distributed database, and / or associated caches and servers) that store one or more sets of instructions 220. As used herein, the term "machine-readable medium" also refers to any medium that can store, encode, or carry a set of instructions 220 that are executed by computing device 140 and cause computing device 140 to perform any one or more of the methodologies of the present disclosure.

[0052] In some scenarios, the hardware entity 214 includes electronic circuitry (e.g., a processor) programmed to facilitate bonding of electronic components (e.g., chips) onto a substrate. In this regard, it should be understood that the electronic circuitry can access and execute software applications 222 installed on the computing device 140. The software applications 222 are generally operable to facilitate control of the adhesive applicator 106, heat / pressure applicator 108, trace printer 110, anisotropic conductive material printer 112, electronic component bonder 114, and / or cutting mechanism 118. Other functions of the software applications 2522 will become apparent as the discussion proceeds. Such other functions may relate to verification of proper operation by the electronic device during manufacture. Verification can be accomplished using an optional wireless communication device 230. The wireless communication device 230 can include, but is not limited to, an RFID tag reader and / or a transmitter.

[0053] Exemplary Methods

[0054] 9, a flow diagram of an exemplary method 900 for bonding an electronic component (e.g., in packaged die form) to a substrate having a rough surface and / or for incorporating an electronic device into a substrate of an article (e.g., a piece of clothing) is provided. The method 900 begins at 902 and continues to 904, where a substrate having a rough surface (e.g., substrate 102 of FIG. 1) is obtained. In some scenarios, the substrate is unwound from a reel / spool (e.g., by dispensing machine 116 of FIG. 1) and placed on a counter (e.g., counter 104 of FIG. 1). A cross-sectional view of an exemplary substrate 1000 obtained at 904 is provided in FIG. 10. As shown in FIG. 10, the substrate 1000 includes a plurality of openings 1002.

[0055] Next, a pad (e.g., pad 500 of FIG. 5) is integrated into and at least partially embedded in the substrate to provide a smooth surface on the substrate upon which an electronic component (e.g., electronic component 400 of FIG. 4) may be mounted. Thus, method 900 involves operations 906-912 for this purpose. At 906, adhesive is applied to or disposed on the substrate. In some scenarios, 906 includes aligning an adhesive applicator (e.g., adhesive applicator 106 of FIG. 1) with a given portion (e.g., portion 142 of FIG. 1) of the substrate (e.g., substrate 102 of FIG. 1) and dispensing adhesive from a nozzle (e.g., nozzle 124 of FIG. 1). A diagram showing adhesive 1100 disposed on substrate 1000 is provided in FIG. 11. The adhesive may include, but is not limited to, an insulating adhesive such as a one-part insulating epoxy (e.g., having part number 3621 available from Henkel Loctite, Germany) or a two-part insulating epoxy (e.g., having part number 2216 available from 3M, USA). The amount of adhesive placed on the substrate 1000 is selected according to a given application and / or the desired shape / size of the pad.

[0056] Heat and pressure are applied to the adhesive at 908 (e.g., via heat / pressure applicator 108 of FIG. 1) for a given time (e.g., 1-20 minutes). A diagram showing heat and pressure being applied to adhesive 1100 is provided in FIG. 12. At 910, the adhesive is allowed to flow into an opening in the substrate. A diagram showing adhesive 1100 in opening 1002 of substrate 1000 is provided in FIG. 13. The adhesive is then allowed to cure at 912. The cured adhesive provides a flat smooth continuous surface to the pad (e.g., surface 502 of FIG. 5). The pad is integrated into and at least partially embedded in the substrate. The pad is also a rigid or semi-rigid structure with a shape / size that does not affect or minimally affects the flexibility of the substrate.

[0057] After the pad is formed, traces are placed on the pad and / or substrate, as shown by 914. Techniques for placing traces on an object are well known in the art. Any known or to be known technique for placing traces on an object can be used herein. In some scenarios, a trace printer (e.g., trace printer 110 of FIG. 1) is used to print a conductive ink (e.g., silver ink) on the substrate. The trace printer can include, but is not limited to, an inkjet printer. A diagram showing traces 1400 placed on a pad 1402 and substrate 1000 is provided in FIG. 14.

[0058] At 916, alignment markings are optionally formed on the pads and / or substrate (e.g., also using printer 110 of FIG. 1). Alignment markings may be provided to facilitate proper placement of electronic components on the pads and / or substrate in subsequent operations. Alignment markings may include, but are not limited to, shapes or lines printed on the pads or substrate (e.g., of a color different from that of the pads or substrate), created by stitching (e.g., using a thread of a color different from that of the pads or substrate), and / or formed using a die (e.g., a die having a color different from that of the pads or substrate). Alignment of components may also be facilitated using an infrared (IR) camera to obtain an image of the contact pads and traces through the backside (i.e., the side opposite the connection side) of the components.

[0059] The electronic component is then bonded to the pads according to ACP or ACF bonding techniques. ACP and ACF bonding techniques are well known. Any known or to be known ACP or ACF bonding technique can be used herein. Thus, method 900 continues at 918-930. At 918, anisotropic conductive material is deposited or otherwise disposed on the traces and / or pads. For example, an anisotropic conductive material printer (e.g., printer 112 of FIG. 1) is used to print the ACP or place the ACF on the conductive traces and / or pads. The anisotropic conductive material printer can include, but is not limited to, an inkjet printer or an extrusion printer. The anisotropic conductive material has the following purposes: to create a vertical electrical connection between the traces and the conductive pads of the electronic component (e.g., conductive pads 402 of FIG. 4) and to securely bond the electronic component to the pads. A diagram illustrating an anisotropic conductive material 1500 disposed on pads 1402 is provided in FIG. 15. In Fig. 15, the anisotropic conductive material 1500 covers the entire pad 1402. The solution is not limited in this respect. The anisotropic conductive material may cover only the portion of the pad where the traces are present, as shown in Fig. 16.

[0060] At 920, the electronic component is aligned with the traces and pads. A diagram showing electronic component 1700 aligned with traces 1400 and pads 1402 is provided in FIG. 17. Once this alignment is achieved, the electronic component is lowered and placed onto the pads and / or anisotropic conductive material such that an electrical bond / connection is made between the electronic component and the traces. A diagram showing electronic component 1700 residing on the anisotropic conductive material is provided in FIG.

[0061] In some scenarios, proper operation of the electronic device including the electronic component and the trace is optionally verified at 924. Verification can be accomplished using an RFID tag reader and / or a transmitter of a computing device (e.g., computing device 140 of FIG. 1). If the electronic device is not operating properly [926: no], the electronic component is replaced with another electronic component as indicated by 928. The method 900 then returns to 924. On the other hand, if the electronic device is operating properly [926: yes], heat and pressure are applied to the anisotropic conductive material at 929, thereby curing the anisotropic conductive material at 930. The electronic component is bonded to the pad and substrate when the anisotropic conductive material is cured. A diagram illustrating an exemplary electronic component 400 bonded to a pad 500 is provided in FIG. 19.

[0062] The electronic device may optionally be coated with a flexible, fluid-resistant material (e.g., a rubber or polymeric material) at 932. At 934, the substrate is optionally cut (e.g., by cutting mechanism 118 of FIG. 1 ) (e.g., to produce a textile substrate article such as a shirt or sheet having an integrated electronic device). 926 is then performed, where method 900 ends or other processing is performed.

[0063] Now referring to FIG. 23, a diagram is provided illustrating an exemplary electronic device fabricated according to the present solution. The electronic device may include, but is not limited to, an environmental sensor or a health monitor. In both scenarios, the electronic device comprises a capacitor or resistor. For example, if the electronic device comprises a temperature sensor, the electronic device senses the temperature via the measured resistance of the resistor. If the electronic device comprises a humidity sensor, the electronic device senses the humidity level via the measured capacitance of the capacitor. The resistor and / or capacitor may be in chiplet form. The chiplet may be coupled to a chip that includes a wireless communication device (e.g., an RF transceiver) so that the measurements can be communicated to a remote device (e.g., a smartphone, a smartwatch, or a personal computer). The present solution is not limited to the details of this example. The electronic device is disposed on a textile substrate 2302, such as a piece of clothing. The piece of clothing and the electronic device provide a textile product (e.g., a shirt with an environmental sensor or a health monitor).

[0064] Although the present solution has been illustrated and described with respect to one or more implementations, equivalent changes and modifications will occur to those skilled in the art upon reading and understanding this specification and the accompanying drawings. In addition, while a particular feature of the present solution may be disclosed with respect to only one of several implementations, such feature may be combined with one or more other features of other implementations as may be desirable and advantageous for any given or particular application. Thus, the breadth and scope of the present solution should not be limited by any of the above-described embodiments. Rather, the scope of the present solution should be defined according to the following claims and their equivalents.

Claims

1. 1. A method for bonding an electronic component to a substrate having a rough surface, comprising: disposing an insulating adhesive on the substrate; applying heat and pressure to the insulating adhesive to cause the insulating adhesive to flow into at least one opening formed in the substrate; curing the insulating adhesive to form at least one pad at least partially embedded within the substrate, the pad including an exposed flat smooth surface; disposing at least one trace on said flat smooth surface of said at least one pad; depositing an anisotropic conductive material on the at least one pad so as to at least cover the at least one trace; placing the electronic component on the at least one pad such that at least one electrical coupling is formed between the electronic component and the at least one trace; and bonding the electronic component to the substrate by curing the anisotropic conductive material; wherein a respective one of the at least one electrical coupling between the electronic component and the at least one trace is formed on a respective one of the at least one pad.

2. The method of claim 1 , wherein the substrate comprises a textile substrate.

3. The method of claim 2 , wherein the textile substrate comprises a woven fabric including the at least one aperture.

4. The method of claim 1 , wherein the insulating adhesive comprises an epoxy.

5. The method of claim 1 , wherein the pad is a rigid or semi-rigid structure having a size and shape selected such that flexibility of the substrate is not affected by the pad.

6. The method of claim 1 , wherein the flat smooth surface of the pad is free of any openings.

7. The method of claim 1 , wherein the electronic component is formed on a die of a semiconductor material, the die being bonded to the substrate via the anisotropic conductive material.

8. The method of claim 1 , wherein the electronic components are formed on a die of semiconductor material packaged as a chip, the chip being bonded to the substrate via the anisotropic conductive material.

9. The method of claim 1 , wherein the anisotropic conductive material comprises an anisotropic conductive paste (ACP) or an anisotropic conductive film (ACF).

10. The method of claim 1 , further comprising verifying proper operation of an electronic device including the electronic component prior to curing the anisotropic conductive material.

11. The method of claim 1 , further comprising coating the electronic component with a flexible, fluid-resistant material after it is bonded to the substrate.

12. The method of claim 1 , wherein the electronic component is electrically coupled to the at least one trace at the same time that the electronic component is bonded to the substrate.

13. 1. An electronic device comprising: A substrate having a rough surface; at least one pad integral with said substrate, said at least one pad being formed of a cured insulating adhesive at least partially embedded within said substrate; at least one trace disposed on a flat, smooth surface of said at least one pad; an anisotropic conductive material deposited on the flat smooth surface of the at least one pad so as to at least cover the at least one trace; an electronic component bonded to the at least one pad via the cured anisotropic conductive material; at least one electrical coupling between the electronic component and the at least one trace is formed on each of the at least one pads; The anisotropic conductive material facilitates the at least one electrical coupling between the electronic component and the at least one trace.

14. The electronic device of claim 13 , wherein the substrate comprises a woven fabric including at least one aperture.

15. The electronic device of claim 13 , wherein the insulating adhesive comprises an epoxy.

16. 14. The electronic device of claim 13, wherein the pad is a rigid or semi-rigid structure having a size and shape selected such that flexibility of the substrate is not affected by the pad.

17. The electronic device of claim 13, wherein the flat smooth surface of the pad is free of any openings.

18. 14. The electronic device of claim 13, wherein the electronic components are formed on a die of semiconductor material, the die being bonded to the substrate via the anisotropic conductive material.

19. 14. The electronic device of claim 13, wherein the electronic components are formed on a die of semiconductor material packaged as a chip, the chip being bonded to the substrate via the anisotropic conductive material.

20. The electronic device of claim 13 , wherein the anisotropic conductive material comprises an anisotropic conductive paste (ACP) or an anisotropic conductive film (ACF).

21. 14. The electronic device of claim 13, wherein proper operation of the electronic device is verified before the anisotropic conductive material is cured.

22. 14. The electronic device of claim 13, further comprising a flexible, fluid-resistant material coating the electronic components.

23. The electronic device of claim 13 , wherein the electronic device comprises an environmental sensor or a health monitor.

24. A textile product comprising: A piece of fabric, at least one pad integral with said fabric piece, said pad being formed from a cured insulating adhesive at least partially embedded in said fabric piece; at least one trace disposed on a flat, smooth surface of said at least one pad; an anisotropic conductive material deposited on the flat smooth surface of the at least one pad so as to at least cover the at least one trace; an environmental sensor or health monitor bonded to the at least one pad through the cured anisotropic conductive material; A textile product, wherein on each of the at least one pad, a respective at least one electrical coupling between the environmental sensor or the health monitor and the at least one trace is formed.

25. 25. The textile product of claim 24, wherein the insulating adhesive comprises an epoxy.

26. 25. The textile product of claim 24, wherein the pad is a rigid or semi-rigid structure having a size and shape selected such that flexibility of the fabric piece is not affected by the pad.

27. 25. The textile product of claim 24, wherein the piece of fabric comprises a woven fabric having a plurality of apertures.

28. 28. The textile product of claim 27, wherein the flat smooth surface of the pad is free of any openings.

29. 25. The textile product of claim 24, wherein the anisotropically conductive material comprises an anisotropically conductive paste (ACP) or an anisotropically conductive film (ACF).

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