Self-adhesive connector tape for RFID devices

Abstract

A radio frequency identification (RFID) device includes: an antenna that defines a gap; and an RFID connector strip that spans the gap and is electrically coupled to the antenna. The RFID connector strip is secured to the antenna by a self-adhesive substance, such as a pressure sensitive adhesive, an isotropic conductive adhesive, or an anisotropic conductive adhesive. The use of a self-adhesive substance allows such RFID devices to be assembled at a facility other than a dedicated RFID device manufacturing facility, which may include a packaging supplier's factory. In addition, such RFID devices allow the creation of a flexible "build-on-demand" system that is capable of producing fewer RFID devices than would typically be produced using conventional methods. Such a system may further test, program, apply printing, and / or cut the RFID devices it assembles.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of U.S. Provisional Utility Patent Application No. 62 / 836,900, filed on April 22, 2019, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present invention relates to radio frequency identification (RFID) devices and more particularly to self-adhesive RFID straps and techniques for attaching the RFID straps to antennas. Background Art

[0004] Radio frequency identification tags and labels (collectively referred to herein as "devices") are widely used to associate objects with identification codes. Radio frequency identification devices typically have an antenna in combination with analog and / or digital electronics, which may include, for example, communication electronics, data storage, and control logic. For example, radio frequency identification tags may be used in conjunction with security locks in automobiles, may be used for access control in buildings, and may be used to track inventory and packages.

[0005] One challenge associated with manufacturing RFID devices is the need to assemble them in specialized RFID manufacturing facilities. Part of the reason for this challenge is the way in which the antenna of such devices is secured to the other components of the device. For example, in one method, an antenna and a separate RFID connection tape (which includes an RFID chip) are provided. An adhesive is applied to a pad of the antenna, and then the RFID connection tape is placed in contact with the adhesive. The adhesive is then cured to secure the RFID connection tape to the antenna. The properties of the adhesive are critical to the function and parameters of the RFID device (for example, the minimum power at which the device can respond to a reader / writer system and the frequency at which the device is configured for optimal operation), which requires advanced manufacturing facilities to achieve the required control. Therefore, this type of RFID device may only be manufactured and assembled at a dedicated facility.

[0006] For convenience, an RFID manufacturing plant or facility may be located near a plant or facility of a product manufacturer, from which the product manufacturer obtains RFID devices for integration into its products. This location of the two plants may reduce the cost of shipping RFID devices from the RFID manufacturer to the product manufacturer. However, if the product manufacturer moves its plant or facility to another location (e.g., to a different country for manufacturing cost considerations), the cost of shipping RFID devices from the RFID manufacturer's plant or facility to the new location may increase significantly, as may the impact on the environment.

[0007] In addition, RFID manufacturers may tend to manufacture RFID devices in large quantities for the sake of economies of scale. Therefore, the number of RFID devices that RFID manufacturers tend to manufacture may be greater than the number that customers require.

[0008] Therefore, there is a need for an RFID device that can be assembled at a factory or facility other than a dedicated RFID device manufacturing factory or facility. There is also a need for an RFID device that can be assembled more simply, thereby allowing a (preferably portable) "build on demand" system that can produce fewer RFID devices than are typically produced using traditional methods.

[0009] It is therefore an object of the present disclosure to provide an RFID device that can be assembled at a factory or facility other than a dedicated RFID device manufacturing factory or facility. It is another object of the present disclosure to provide an RFID device that can be assembled more simply, thereby allowing a (preferably portable) "build-on-demand" system that can produce fewer RFID devices than would normally be produced using conventional methods. Summary of the invention

[0010] Aspects of the present application may be embodied individually or together in the devices and systems described and claimed below. The aspects may be used individually or in combination with other aspects of the invention described herein, and the description of the aspects together is not intended to exclude: the use of the aspects alone, or the protection of the aspects in different combinations or alone, as set forth in the scope of the invention claims attached hereto.

[0011] A radio frequency identification device and methods of making and using the same are described herein. The radio frequency identification device includes an antenna defining a gap and a radio frequency identification connection strip electrically coupled to the antenna across the gap.

[0012] In some embodiments, the RFID connection band is fixed to the antenna by a self-adhesive substance or material. In some embodiments, the self-adhesive substance or material includes or is: a pressure-sensitive adhesive, an isotropic conductive adhesive (such as an adhesive paste or film), or an anisotropic conductive adhesive (such as an adhesive paste or film).

[0013] A method of assembling an RFID device is also described. In some embodiments, the method includes providing an antenna and an RFID connection strip. The method further includes securing the RFID connection strip to the antenna using a self-adhesive substance as described above so that the RFID connection strip is electrically coupled to the antenna across a gap defined by the antenna.

[0014] Also described herein is a system for assembling the RFID device. In some embodiments, the system for assembling the RFID device includes: an antenna creation station configured to form an antenna, the antenna defining a gap. In some embodiments, the system includes an antenna creation station as described above and a connection tape attachment station, the connection tape attachment station being configured to electrically couple the RFID connection tape to the antenna across the gap, and the RFID connection tape being fixed to the antenna by a self-adhesive substance or material as described above. In some embodiments, the system includes the creation station and attachment station described above, and further includes: a test station configured to test the performance of the RFID device assembled by the system. In other embodiments, the system includes the creation station, attachment station and test station as described above, and further includes: a programming station configured to program the RFID chip of the RFID device assembled by the system. The above system may further include: a printing station configured to apply a human-readable indicia to the RFID device assembled by the system; and / or a cutting station configured to cut a portion of the RFID device assembled by the system. The various stations described above may be arranged to be located at one location (eg, within one facility), at multiple locations, or at multiple facilities at the same location. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a schematic side elevation view of an antenna of a radio frequency identification device according to the present disclosure;

[0016] Figure 1A yes Figure 1 A schematic top plan view of an antenna;

[0017] Figure 2 yes Figure 1A schematic side elevation view of an antenna and a radio frequency identification connection strip to be fixed to the antenna using a self-adhesive substance;

[0018] Figure 3 yes Figure 2 A schematic side elevation view of an antenna and an RFID connection strip secured together to define an RFID device;

[0019] Figure 3A yes Figure 3 A schematic top plan view of a radio frequency identification device;

[0020] Figure 4 yes Figure 2 A schematic side elevation view of an RFID connection tape provided with a first exemplary self-adhesive substance;

[0021] Figure 5 yes Figure 2 A schematic side elevation view of an RFID connection tape provided with a second exemplary self-adhesive substance;

[0022] Figure 6 yes Figure 2 A schematic side elevation view of an RFID connection tape provided with a third exemplary self-adhesive substance; and

[0023] Figure 7 is a schematic diagram of a “build-on-demand” system for manufacturing radio frequency identification devices according to the present disclosure. DETAILED DESCRIPTION

[0024] Detailed embodiments of the present invention are disclosed herein as required; however, it should be understood that the disclosed embodiments are merely examples of the present invention, which may be embodied in various forms. Therefore, the specific details disclosed herein should not be interpreted as limiting, but only as a basis for the scope of the invention and as a representative basis for teaching those skilled in the art to use the present invention in various ways in almost any appropriate manner.

[0025] Figure 1 An antenna 10 of the type that can be incorporated into the RFID device described herein is shown. The antenna 10 can be made and configured in a variety of different ways without departing from the scope of the present disclosure. However, in one embodiment, the antenna is configured in a conventional manner, having a pair of pads 12, 14 ( Figure 1A ).

[0026] Rather than applying adhesive to the spacers 12, 14 (as in conventional methods), a self-adhesive substance or material 18 having defined properties (e.g., thickness and real and imaginary parts of the dielectric constant) is applied to the RFID connection tape 20 to be secured to the antenna 10 ( Figure 2 ) to define the RFID device 22 ( Figure 3 and Figure 3A The self-adhesive substance or material 18 is configured to adhere to the antenna 10 to fix the RFID connection strip 20 (such as a pad of the RFID connection strip 20) to the antenna 10 (the RFID connection strip 20 spans the gap 16 and is electrically coupled to the antenna 10, such as Figure 3A ), without the need for a separate curing process (as required in conventional methods). Figure 2 A self-adhesive substance or material 18 is shown applied to an RFID tape 20, but it should be understood that the self-adhesive substance 18 may in turn be applied to the antenna 10 or to both the antenna 10 and the RFID tape 20. In another embodiment, a first substance may be applied to the antenna 10 and a second substance may be applied to the RFID tape 20, the two substances (when in contact with each other) combining to produce a self-adhesive substance or material. While it is within the scope of the present disclosure to apply the self-adhesive substance or material 18 (or a component thereof) to the antenna 10, it may be advantageous to apply the self-adhesive substance or material 18 only to the RFID tape 20 because applying the substance or material to the antenna 10 may require controlled printing. However, in other embodiments, the self-adhesive substance or material (or a component thereof) may be applied or printed to the antenna in a pattern.

[0027] The nature of the self-adhesive substance 18 may vary without departing from the scope of the present disclosure. For example, in one embodiment, the self-adhesive substance 18 is or includes a pressure-sensitive adhesive 18a, such as Figure 4 In another embodiment, the self-adhesive material 18 is or includes an isotropic conductive adhesive 18b (eg Figure 5 ), the isotropic conductive adhesive 18b can be configured as, for example, a paste or a film. In another embodiment, the self-adhesive material 18 is or includes an anisotropic conductive adhesive 18c (such as Figure 6 ), the anisotropic conductive adhesive 18c can be configured as, for example, an adhesive paste or a film. It should be understood that Figures 4 to 6 The self-adhesive substances or materials shown are exemplary only, and self-adhesive structures according to the present disclosure may have different compositions without departing from the scope of the present disclosure.

[0028] Depending on the properties of the self-adhesive substance or material 18, the RFID connection tape 20 can be coupled to the antenna 10 through reactance, such as E-field coupling, inductive H-field coupling, or a combination of the two. The coupling is a function of the properties of the self-adhesive substance or material 18, such as the capacitance is affected by the thickness of the self-adhesive substance or material 18 (i.e., doubling the thickness causes the capacitance to decrease to 1 / 2 of the original amount). The coupling is also related to the real and imaginary parts of the dielectric constant, and doubling the real part of the dielectric constant increases the capacitance to twice the original amount. The effect of the imaginary part is more complicated because the increase is associated with higher wireless RF energy losses flowing through the material between the antenna pads 12, 14 and the pads of the RFID connection tape 20 (through the self-adhesive substance or material 18). Therefore, care should be taken when selecting and applying the self-adhesive substance or material 18 to ensure that it can achieve the expected, generally optimal performance of the final RFID device 22.

[0029] Using a self-adhesive substance or material 18 to join the antenna 10 and the RFID connection strip 20 may have many advantages. For example, compared to conventional methods, Figures 1 to 3 The assembly process shown in is simplified because there is no need to cure the self-adhesive substance or material 18 (e.g., by applying heat or ultraviolet light) to secure the antenna 10 to the RFID connection strip 20. By simplifying the assembly process, the RFID device 22 (after the RFID device manufacturer manufactures the RFID connection strip 20) can be assembled outside of a dedicated RFID device manufacturing plant or facility, including in a plant or facility that is not suitable for the precision processes that are typically performed (and required) when assembling RFID devices according to traditional methods. For example, Figures 1 to 3 The illustrated assembly process may be performed in a factory (such as a packaging supplier's factory) or a facility that is primarily used to manufacture the product into which the RFID device 22 will be incorporated.

[0030] In addition to the components of the RFID device 22 (primarily the RFID connection strip 20) being transferred from the manufacturer to the assembly site, intellectual property (such as antenna design and attachment method) can also be transferred to allow simplified on-site assembly of the RFID device 22. For example, it may be beneficial to provide the assembly site with the tools and techniques required to print conductive ink or form foil into an antenna (e.g., by punching or cutting foil) rather than providing the assembly site with a finished antenna (although it is also within the scope of the present disclosure for the manufacturer to provide the assembler with a formed antenna or a finished antenna). In another example, the assembler can be provided with the tools and techniques required to test the assembled RFID device.

[0031] The reduction in machine complexity provided by the RFID devices described herein also allows the use of small (e.g., small footprint), potentially mobile, "build-on-demand" systems that can assemble the RFID devices described herein, such as the RFID device 22. One or more such systems may be installed in or near the assembler's facility or factory. Depending on the location where such a system is installed, a support system may be provided that may include power and data communications, such as a satellite transceiver, if such capabilities are not available or are unreliable at the location. By assembling the RFID devices on site, the disadvantages of relocating the assembler's facility or factory away from the RFID device manufacturer's factory or facility (including increased shipping costs and environmental externalities) may be reduced.

[0032] Figure 7 An exemplary "build-on-demand" system 24 is shown in FIG. The system 24 may be provided with a number of workstations at which different stages of RFID device creation and assembly are performed, and the system 24 includes a mechanism (e.g., a conveyor) for transporting RFID devices 22 or components thereof from one workstation to the next. For example, an antenna creation station 26 may include the components required to form the antenna 10. If the system 24 is provided with an antenna creation station 26, it may be advantageous for the antenna 10 to be digitally defined (i.e., having a changeable pattern without physically adjusting the system 24). Examples of digitally defined antennas may include inkjet deposition of conductive ink or a laser system configured to cut foil materials, although other methods (e.g., selective abrasion) may also be used. It is also within the scope of the present disclosure for the system 24 to omit the antenna creation station 26 and instead provide the system 24 with a formed antenna 10. However, the antenna creation station 26 may be preferred in order to provide the assembler with greater flexibility and reduce dependence on the RFID device manufacturer.

[0033] Additional workstations of the system 24 may include: a connection tape attachment station 28, which is configured to electrically couple the RFID connection tape 20 to the antenna 10 via the self-adhesive substance 18, as described above. A testing station 30 (if provided) is positioned downstream of the connection tape attachment station 28, and the testing station 30 can be configured to test the performance of the RFID device 22 assembled by the system 24. A programming station 32 (if provided) can be configured to program the RFID chip 34 of the RFID device 22 assembled by the system 24. If provided, a printing station 36 can be configured to apply human-readable markings to the RFID device 22 assembled by the system 24. If provided, a cutting station (referenced as 38) can be configured to cut portions of the RFID device 22 assembled by the system 24 using, for example, an XY cutter or a laser. The RFID device 22 assembled by the system 24 can be incorporated into a piece of merchandise or the like (e.g., a product label) after leaving the system 24, as indicated at reference numeral 40. It should be understood that the "build on demand" system according to the present disclosure can provide less than Figure 7 All workstations shown in, or there are additional workstations not shown. In addition, it should be understood that the various different workstations of the "build on demand" system according to the present disclosure can be provided in any suitable order (e.g., positioning the printing station 36 upstream of the programming station 32).

[0034] The size and portability of the "build on demand" system may vary depending on its configuration and functionality. For example, it is contemplated that such a system may be configured to fit inside a standard shipping container for easy transportation over land and / or sea. In another embodiment, such a system may be configured to facilitate air transportation to assist in rapid movement from one location to another. In yet another embodiment, the "build on demand" system may be provided as a "desktop" unit similar in size to the printers that are provided to product manufacturers as part of their RFID offerings for printing variable, human-readable information.

[0035] The present invention takes into account that, for the sake of economies of scale, RFID manufacturers may prefer to manufacture RFID devices in large quantities. The number of RFID devices that RFID manufacturers prefer to manufacture may be greater than the number required by customers. In one embodiment currently contemplated by the present invention, a wet tape structure for an inlay can be created. The present invention contemplates that the adhesive used in association with the tape is a pressure sensitive adhesive, but is not limited to this. There are several ways to construct a wet tape. For example, in one embodiment, in a conventional wet tape construction process, the tape is made in a chip attach machine using a lead frame, a chip adhesive and at least one chip. The tape can then be converted into a wet tape by: 1) using a laminating transfer tape and / or 2) applying at least one adhesive with a liner on a reel before cutting into individual tapes (such as pressure sensitive tapes).

[0036] In another embodiment, it is currently contemplated to construct a wet strap by first converting the leadframe so as to first make a wet leadframe. The wet leadframe may be run through a die attach machine to apply at least one die adhesive and attach at least one die to make a finished inlay. This wet first strap approach allows for the attachment of a die that is relatively high cost compared to the rest of the inlay at the end of the manufacturing process, thereby reducing the risk of damage to the die and reducing the overall cost of the strap. It is noted that for both wet inlay construction methods briefly mentioned herein, the leadframe may be made by: 1) a conventional etching process; 2) a hybrid process that includes at least two cutting steps, one of which may use a laser; and / or 3) using a laser. It is contemplated that the leadframe may be made by only one of these methods or a combination of the various methods mentioned herein.

[0037] In another embodiment currently envisioned for wet connection tape construction, a wet hybrid lead frame process is utilized. This process is similar to the wet first connection tape method, but the lead frame can be flood coated or the adhesive can be printed on the backing paper. Then, the conductor laminate, PET or aluminum on paper can be laminated, and the bonding area (chip gap) is cut. The cutting can be done by laser, mechanical die cutting, or any other cutting method known in the art. Next, the cross web is cut and the web is torn off to form each lead frame on a reel. In one embodiment, these lead frames can then undergo a chip attachment process. This wet hybrid lead frame process allows for a faster and simpler manufacturing process and lower tool and material costs.

[0038] It should be understood that the embodiments described above are illustrations of some applications of the principles of the present application. Those skilled in the art may make many modifications without departing from the spirit and scope of the present application as claimed, which includes combinations of features that are disclosed or claimed separately herein. For these reasons, the scope of the present invention is not limited to the above description, but as set forth in the accompanying claims, and it should be understood that the claims may be directed to features of the present invention, including combinations of features that are disclosed or claimed separately herein.

Claims

1. A radio frequency identification device, comprising: an antenna defining a gap; as well as an RFID connection strip electrically coupled to the antenna across the gap, wherein the RFID connection tape is fixed to the antenna by a self-adhesive material, and the self-adhesive material is applied only to the RFID connection tape; and wherein the self-adhesive substance has a defined thickness and real and imaginary parts of a dielectric constant; and The self-adhesive substance is configured to adhere to the antenna to fix the RFID connection strip to the antenna without requiring a separate curing process.

2. The RFID device according to claim 1, wherein: The self-adhesive material includes a pressure-sensitive adhesive.

3. The RFID device according to claim 1, wherein: The self-adhesive material includes an isotropic conductive adhesive.

4. The RFID device according to claim 3, wherein: The isotropic conductive adhesive includes an adhesive paste.

5. The RFID device according to claim 3, wherein: The isotropic conductive adhesive includes a film.

6. The RFID device according to claim 1, wherein: The self-adhesive material includes anisotropic conductive glue.

7. The RFID device according to claim 6, wherein: The anisotropic conductive adhesive includes an adhesive paste.

8. The RFID device according to claim 6, wherein: The anisotropic conductive adhesive includes a film.

9. A method of assembling a radio frequency identification device, comprising: providing an antenna, the antenna defining a gap; Provide RFID connection belt; as well as fixing the RFID connection strip to the antenna using a self-adhesive material so that the RFID connection strip is electrically coupled to the antenna across the gap, The self-adhesive substance is applied only to the RFID connection strip; and wherein the self-adhesive substance has a defined thickness and real and imaginary parts of a dielectric constant; and The self-adhesive substance is configured to adhere to the antenna to fix the RFID connection strip to the antenna without requiring a separate curing process.

10. The method of claim 9, wherein: The self-adhesive material includes a pressure-sensitive adhesive.

11. The method of claim 9, wherein: The self-adhesive material includes an isotropic conductive adhesive.

12. The method of claim 11, wherein: The isotropic conductive adhesive includes an adhesive paste.

13. The method of claim 11, wherein: The isotropic conductive adhesive includes a film.

14. The method of claim 9, wherein: The self-adhesive material includes anisotropic conductive glue.

15. The method of claim 14, wherein: The anisotropic conductive adhesive includes an adhesive paste.

16. The method of claim 14, wherein: The anisotropic conductive adhesive includes a film.

17. A system for assembling a radio frequency identification device, comprising: an antenna creation station configured to form an antenna, the antenna defining a gap; as well as a strap attachment station configured to electrically couple an RFID strap to the antenna across the gap, wherein the RFID connection tape is fixed to the antenna by a self-adhesive material, and the self-adhesive material is applied only to the RFID connection tape; and wherein the self-adhesive substance has a defined thickness and real and imaginary parts of a dielectric constant; and The self-adhesive substance is configured to adhere to the antenna to fix the RFID connection strip to the antenna without requiring a separate curing process.

18. The system of claim 17, further comprising: A test station is configured to test the performance of the radio frequency identification device assembled in the system.

19. The system of claim 17, further comprising: A programming station is configured to program the RFID chip of the RFID device assembled by the system.

20. The system of claim 17, further comprising: A printing station is configured to apply human-readable indicia to radio frequency identification devices assembled by the system.

21. The system of claim 17, further comprising: A cutting station is configured to cut portions of the RFID devices assembled by the system.

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