HK1134380A - Wireless communication device using voltage switchable dielectric material - Google Patents

Description

Wireless communication device using voltage variable dielectric material

RELATED APPLICATIONS

This application claims priority to U.S. provisional patent application 60/739,725, entitled "RFID Tag Using Voltage switch Electrical Material", filed 22/11/2005, which is incorporated herein by reference.

This application also claims priority from 60/740,961, U.S. provisional patent application entitled "Light EmittingDevices With ESD Characteristics", filed on 29/11/2005, which is hereby incorporated by reference.

Technical Field

The disclosed embodiments relate generally to wireless communication devices. More specifically, embodiments described herein include those wireless communication devices that incorporate or incorporate voltage variable dielectric materials (voltageswitchable dielectric materials).

Background

The number of wireless communication devices and applications is increasing. These examples include chipsets and components for cellular communication devices, short-range wireless communication via WiFi (IEE E802.11 or bluetooth), and many other applications such as Radio Frequency Identification (RFID) tags.

RFID tags are becoming a common method of identifying and tracking objects during their life cycle. RFID tags are used in a wide variety of applications, such as marking goods and products in manufacturing, shipping, and distribution. RFID tags are also used for wireless transmission for military and civilian use. While RFID tags are effective in use, RFID components are fragile. In particular, RFID tags are sensitive to various threats from the external environment, since they are semiconductor devices in nature.

Drawings

FIG. 1 illustrates an apparatus for generating radio frequency identification information, wherein the apparatus is constructed to house a voltage variable dielectric material, according to one embodiment of the present invention.

Fig. 2A shows a first portion of a Radio Frequency Identification (RFID) tag device provided with a voltage variable dielectric material according to one embodiment of the present invention.

Fig. 2B illustrates a second portion of the RFID tag device shown in fig. 2A, in accordance with one embodiment of the present invention.

FIG. 2C illustrates an alternative application of one or more embodiments described herein.

Figure 3 illustrates a technique for forming a wireless communication device having VSD material integrated into its electrical components and/or elements, according to one embodiment of the present invention.

Figures 4A-4E illustrate a process for forming an RFID tag device using VSD material in accordance with one or more embodiments of the present invention.

Detailed Description

Embodiments described herein provide for the use of a voltage variable dielectric material (VSD) as part of a wireless communication device, such as a tag or chip set. The VSD material may be provided as part of the package or integrated or combined with electrical components and elements of the wireless communication device. As provided by one or more embodiments, the integration of VSD material can protect wireless communication devices from voltage transients, such as electrostatic discharge (ESD) and Electrical Overstress (EOS), as well as from moisture, shock, and other electrical or mechanical hazards.

Examples of wireless communication devices that may be suitable for use with embodiments described herein include RFID tags, cellular communication chips, short-range wireless communication chips and devices (e.g., provided in accordance with the bluetooth or IEEE802.11 standards), and other devices capable of receiving or transmitting microwave signals for communication.

As used herein, "voltage variable material" or "VSD material" is any composition or combination of compositions having the following characteristics: a material is either dielectric or non-conductive at all times unless a voltage is applied to the material that exceeds the level of the material's properties, in which case the material becomes conductive. Thus, VSD material is dielectric unless a voltage exceeding a characteristic level (e.g., caused by an ESD event) is applied to the material, in which case the VSD material becomes conductive. VSD material can also be any material that can be characterized as non-linear resistive material.

There are a wide variety of VSDMs. Examples of voltage variable dielectric materials are given in documents such as us 4,977,357, us 5,068,634, us 5,099,380, us 5,142,263, us 5,189,387, us 5,248,517, us 5,807,509, WO 96/02924 and WO 97/26665. In one implementation, the VSDM material corresponds to the material manufactured and sold under the trade name "SURGX".

One or more embodiments provide for the use of VSD material that includes 30-80% insulation, 0.1-70% conductors, and 0-70% semiconductors. Insulating materials include, but are not limited to, silicone polymers, epoxies, polyimides, polyethylenes, polypropylenes, polyphenylene oxides, polysulfones, sol gel materials, milk crystals (polymers), silicon dioxide, aluminum oxide, zirconium oxide, and other metal oxide insulators. Examples of conductive materials include metals such as copper, aluminum, nickel, stainless steel. Semiconductor materials include organic and inorganic semiconductors. Some inorganic semiconductors include silicon, silicon carbide, boron nitride, aluminum nitride, nickel oxide, zinc sulfide. Examples of the organic semiconductor include poly-3-hexylthiophene, pentacene, perylene, carbon nanotube, and C60 fullerene. The specific configuration and composition may be selected to best suit the particular application of the VSD material.

According to embodiments, a wireless communication device includes a combination of conductive elements configured to enable transmission or reception of wireless signals. VSD material can be provided in a device having the property that the device changes from dielectric to conductive when a voltage exceeding a characteristic voltage level is applied to the material. The VSD material may be positioned to ground at least a portion of the device when subjected to a voltage that exceeds a characteristic voltage level.

In one embodiment, the VSD material is integrated into the electrical or mechanical components of the RFID device. VSD material may be provided to protect the device from electrical events such as electrostatic discharge (ESD).

According to one embodiment, the VSD material partially or wholly encapsulates the RFID device.

In addition, one or more embodiments incorporate VSD material on an underlying substrate or board on which a wireless communication device (e.g., an RFID device) is placed. VSD material may also be applied to a substrate that is subsequently used to form some or all of the remaining devices. An ion deposition process, such as electroplating, can be used to form conductive elements on the substrate when the VSD material is in a conductive state.

In addition, one or more embodiments provide for incorporation of VSD material into the enclosure, intermediate layer, or into some other structure that is integrated or connected to the wireless communication device.

According to one embodiment, an apparatus for generating a radio frequency identification signal is provided. The apparatus includes a package, a substrate provided in the package, and one or more logic components provided on the substrate. The one or more logic elements may be capable of generating data, including identification data. Transmitting means may be provided on the substrate which generates a signal carrying the identification information. The device may also include VSD material provided within the package. The VSD material can be positioned to ground at least a portion of the device when subjected to a voltage that exceeds the characteristic voltage level of the VSD.

In addition, one or more embodiments provide for the use of VSD material in electroplating processes or other ion deposition processes for forming conductive elements and components of wireless communication devices. In one embodiment, the substrate is formed to incorporate a layer of VSD material. A layer of resistive material is provided over the layer of VSD material. The resistive material is selectively removed to form a pattern that includes locations that are to be located under electrical components of the wireless communication device. The components may include any one or more of (i) one or more logic elements to be embedded in the device, (ii) a wireless communication element (e.g., an antenna), (iii) an interconnection element between the one or more logic elements and the wireless communication element, (iv) a power source, or (v) an interconnection element between the power source and the one or more logic elements or the wireless communication element. Once the pattern is formed, a voltage is applied to the substrate that exceeds the characteristic voltage level of the VSD material. The substrate is exposed to a conductive material while the voltage is applied to cause the conductive material and the VSD material to bond. This results in the formation of conductive lines on the substrate where at least a portion of the pattern is provided.

In particular, one or more embodiments provide for removing non-conductive or resistive material based on identification of a location where an electrical component or part of the wireless communication device is to be located. For example, in an RFID device, the selected location may coincide with the location of an antenna element, or the location of a conductive line extending between the antenna element and the microchip or power source.

Wireless communication device with VSD material

Figure 1 illustrates a wireless communication device incorporating or integrating VSD material in accordance with one embodiment of the present invention. A wireless communication device of the type depicted in fig. 1 may correspond to an RFID tag, a cellular chip, a short-range radio chip (e.g., a bluetooth or WiFi device), or a microwave communication component.

In one embodiment, an apparatus 100 includes a package 105 including a communication element 120, a logic element 130, and a power source 140. The package 105 is not necessary in all applications, such as where the device 100 is to be incorporated into the housing of another device (e.g., a cellular telephone). The power source 140 may correspond to an active or passive structure to provide power to the communication element 120 and the logic element 130. The logic element 130 may correspond to a chip (e.g., a microchip), or a combination of circuits and devices capable of generating data. For example, in an RFID application, the microchip may generate identification information, and the communication element 120 is a transmitter that transmits a radio frequency signal that communicates with the identification information provided by the microchip.

In other wireless device embodiments, the communication element 120 may be an inductive or capacitive element that creates a detectable change in electric field. The logic element 130 may also have more complex logic. For example, in a cellular chip, the logic element may correspond to a processor and associated logic that performs various processes via signals provided from the communication element 120.

Depending on the type and function, other components, such as memory, may be included within the package and conductively coupled to the power source 140 and logic elements 130. For example, in an RFID application, the communication element 120 may correspond to an antenna that generates a radio frequency signal that utilizes signal modulation characteristics or the like to provide identification information. If the device 100 has an active power source, the power source 140 may include an on-board battery (on-board). If the device 100 is passive (e.g., an RFID device), the power source 140 may correspond to a circuit board or receiver that generates energy from an external signal or application. For example, as a receiver, the power supply 140 may be configured to receive radio frequency signals from other devices and then generate internal power signals to activate the communication element 120 and the logic element 130.

An interconnect element 122 may enable communication of identification information and other data from the logic element 130 to the communication element 120. Similarly, the power connection element 142 may distribute power from the power source 140 to the communication element 120 and/or the logic element 130. Although power source 140 is shown as a discrete component, it may be implemented as a distributed element, or in combination with other elements. For example, other components may be equipped with receiver circuit boards so that those components and surrounding components are powered by the application of an external radio frequency signal.

In one embodiment, the VSD material is integrated, incorporated, or combined into the electrical components and elements of the device 100. In accordance with one or more embodiments, VSD material may be integrated or combined with the communication element 120, with the interconnect element 122 extending conductivity between the communication element 120, the logic element 130, and the power connection element 142. Many other locations for the VSD material 110 may exist. For example, the logic element 130 can be integrated or combined with the VSD material 110, or placed on or beside the VSD material. Similarly, a receiver including a power source 140 can be combined or integrated with the VSD material 110. The VSD material 110 can provide protection against ESD events and EOS when combined or integrated with the electrical components and elements of the device 100. Further, as described with other embodiments, the application of VSD material 110 can be used in electroplating and other metal deposition processes to enable conductive elements, including electrical components and elements of device 100, to be integrally formed with the VSD material 110.

Additionally or alternatively to the embodiments described above, the VSD material 110 may be combined or integrated into the mechanical structure of the device 100. In one embodiment, the VSD material 100 may form a portion or all of the components of the package 105. The VSD material may also be used as part of other components used to package the various electrical components of device 100. Additionally or alternatively, the VSD material 110 can also be used to adhere a portion of the package 105. When using the mechanical structure, the VSD material 110 can provide protection against a variety of events, such as those with high level electrostatic discharges.

RFID tag with VSD material

Figures 2A and 2B illustrate the construction of an RFID device using VSD material, according to one embodiment of the present invention. One embodiment of fig. 2A shows those electrical components provided with a first portion 210 of the RFID device, while a second portion 260 primarily provides packaging. Other embodiments provide that electrical components and elements are provided on both portion 210 and portion 260.

In the embodiment shown in fig. 2A, the first portion 210 includes a microchip 220 as a logic element, an antenna 224 as a communication element, and a power source 230. The microchip 220 generates data that includes identifying information regarding the characteristics or attributes of the RFID device. The antenna 224 may be comprised of conductive traces that may emit radio frequency signals when energized. The interconnect element 222 may extend electrical conductivity between the microchip 220 and the antenna 224. When the microchip 220 is energized, the microchip may signal identification information and other data to the antenna 224, where the data is signaled to the RFID scanner or reader.

The radio frequency signal generated by antenna 224 may have a characteristic (e.g., frequency) corresponding to the identification information. In one embodiment shown, the antenna 224 includes a plurality of line elements 225 that are concentrically arranged. Other arrangements of wires or circuit boards may also be employed for the antenna 224.

In one embodiment, the power source 230 corresponds to an on-board battery (battery) that generates a power signal to power the antenna 224 and the microchip 220. In another embodiment, the power source 230 may correspond to a circuit board, or distribution of electrical lines, and/or a resource capable of receiving and being powered by an externally applied radio frequency signal. In the latter case, the power source may be separate from or combined with the conductive element serving other purposes. Conductive leads (leads) and lines that provide power from the power source 230 to other elements and components are referred to as power source connection elements 232.

The RFID device formed by the combination of section 210 and section 260 may be equipped with VSD material in any of a number of locations. Location 242 and 250 represent possible locations where VSD material can be integrated into the RFID device, according to one or more embodiments of the present invention. Since locations 242-250 are representative of other similar locations and regions on the device, the discussion of VSD material at any given individual location 242-250 also applies to the class of locations represented by that location.

Location 242 and 246 are representations of locations or areas on the RFID device where VSD material may be integrated or combined with electrical elements or components of the RFID device. According to one embodiment, VSD material may be provided at a location represented by location 242. In such a location, the VSD material may be combined or integrated with a conductive power source connection element 232, the conductive power source connection element 230 extending conductivity between the power source 230 and other elements of the RFID device.

Additionally or alternatively, VSD material can be provided at a location represented by location 244. In such a position, the VSD material may be combined or integrated with those line elements 225 that form the antenna 224. In this manner, VSD material may be provided to, or as part of, the antenna elements 224 of the RFID device.

Similarly, VSD material may be provided at locations represented by location 246. In such a position, the VSD material may be combined or integrated with an interconnect element 222 that extends conductivity between microchip 220 and antenna 224. Many other locations for VSD material may be provided according to other various embodiments. For example, VSD material may be provided to or below microchip 220 or power source 230.

The manner in which VSD material is combined or integrated with electrical elements can vary. In one embodiment, the VSD can be placed on or beside electrical components or elements (e.g., line 225 of antenna 224). Alternatively, the VSD material may be used to form (e.g., by bonding or deposition) those conductive elements provided at the plurality of locations, as with the embodiment described for fig. 4A-4E.

Mechanically, the first portion 210 and the second portion 260 may be formed from any of a variety of materials to achieve physical characteristics suitable for the application of the RFID device. For example, the portion 210 and the portion 260 may be formed of a flexible material to form a package 202 suitable for applications where the device may be subject to bending or flexing. Alternatively, rigid materials may be utilized to form packaging for other applications in which the device may be bumped, dropped, or otherwise subjected to physical damage. One or more embodiments provide that the VSD material is integrated or combined into mechanical components of the RFID device, etc., as an alternative or in addition to embodiments in which the VSD is integrated or combined with electrical elements and components.

Referring to fig. 2A and 2B, VSD material can be provided at locations represented by location 248. In such a location, the VSD material may be combined or integrated into the wrapper 202. Alternatively, the VSD material may be provided as a layer or thickness layer to an underside of the package, or as a strip extending through either of the portions 210 or 260. In one embodiment, the formation of VSD material may be matched to the physical characteristics and properties of the material used for the package. For example, the composition of the VSD material can be varied to match the composition of the package 202.

Referring to fig. 2A and 2B, one or more embodiments also provide that VSD material can be provided as an adhesive at locations represented by location 250 to join portions 210 and 260 together. According to one embodiment, the composition of the VSD material may be configured to enhance adhesion properties. The VSD material can promote adhesion between portion 210 and portion 260 when applied to the location represented by location 250.

FIG. 2C illustrates an alternative application using one or more embodiments described herein. In the embodiment of fig. 2C, a wireless device 270 includes a substrate 274 on which components (or chips or other logic elements) such as a processor 276 and other resources 278 (e.g., memory) are located.

A communication element 280 (transmitter/receiver) may also be provided on the pad 274. The communication element 280 may generate or receive radio frequency signals (e.g., in the cellular range or range defined by IEEE 802.11) or, alternatively, provide or detect inductive or capacitive field changes.

Various conductive elements in the form of lines 275 and leads may be distributed between processor 276 and resource 278. A power source 282 in the form of an on-board battery, or a receiver for receiving wireless power transmissions, may also be incorporated into the substrate 274. The substrate 274 may also include outbound and inbound communication lines 284, 285 to enable signal communication with the processor 276.

In one embodiment, the outbound and inbound communication lines 284, 285 may extend to a connector or port (e.g., a cable) to allow another processor to receive communications from the processor 276. In one embodiment, the outward and inward communication lines 284, 285 may extend to the wireless communication element 280 to implement a wireless communication port.

In accordance with one or more embodiments, VSD material may be integrated or bonded with mechanical or electrical elements of device 270. The location represented by location 292 shows that VSD material can be incorporated or integrated with communication element 280. The locations represented by location 294 show that VSD material can be combined or integrated with the outbound or inbound communication lines 284, 285. Furthermore, as described for the embodiment of figure 2A (RFID application), one or more embodiments can provide for integration or incorporation of VSDs with other resources, components, and conductive elements of device 270. For example, VSD material may: (i) integrated or integrated with the power source 282 and/or power lines extending therefrom, or (ii) integrated or integrated with the processor 276 and/or conductive lines extending communication between the processor 276 and the communication element 280 or other resource 278.

The VSD material may also be combined with the housing or other mechanical structure of device 270, as described for the embodiment of fig. 2A and 2B. The VSD material may also be used in combination with an adhesive, or in lieu of the use of an adhesive, to mechanically secure an element or housing.

With respect to any of the embodiments described with respect to figures 2A-2C, the VSD material can be designed or selected to have a characteristic voltage level that is lower than the breakdown voltage of the wireless communication device (e.g., RFID tag). In other words, embodiments may provide that the characteristic voltage level of the VSD material is below a minimum level (e.g., transient voltage from a surge) that would render the wireless communication device inoperable.

Forming devices from VSD material

Figure 3 illustrates a technique for forming a wireless communication device that integrates VSD material into its electrical components and/or elements, according to an embodiment of the present invention. The method as described in fig. 3 may be used to form a device (e.g., RFID tag, cellular chip, WiFi/bluetooth chip, etc.) that transmits signals including radio frequency signals, microwave signals, and signals for capacitive/inductive applications.

The following documents describe general techniques for plating or forming circuits and components using VSD material: U.S. patent application 10/941,226, entitled "Current bearing Structure Using Voltage switch Electrical Material", filed on 14.9.2004, Lex Kosowsky is the only inventor; the above application is a continuation of U.S. Pat. No. 6,797,145 (official U.S. patent application No. 10/315,496), filed in 2002, 12, 9, entitled "Current CarryingStructure Using Voltage switching Electrical Material", LexKosowsky is the sole inventor; the above application is a continuation of U.S. patent application 09/437,882, filed 10, 11.1999 and which has been abandoned; the above application claims priority from U.S. provisional application 60/151,188, filed on 27.8.1999, which has expired. All of the aforementioned applications are individually incorporated herein by reference for their respective purposes.

At step 310, VSD material is applied to a substrate or surface on which conductive features and elements are to be disposed. The amount of VSD material that can be deposited onto the substrate ranges from 1 micron to 1000 microns in thickness depending on the application of the process.

In step 320, a layer of non-conductive material is provided over the VSD material. For example, a photoresist material may be deposited over the VSD material.

Step 330 provides that a non-conductive layer is molded over the substrate. The molding process exposes areas that coincide in location with where subsequent conductor elements are formed that will comprise portions of the wireless device. For example, the molding may selectively designate exposure regions that coincide with formation positions of emission elements including inductance or capacitance elements for emitting signals. In one embodiment, a mask may be applied to the non-conductive layer in order to pattern the non-conductive layer. The exposed area of the pattern coincides with the position of the conductive elements or components that will form the emissive components of the device. For a wireless device as described in fig. 1, the exposure area coincides with the location where the line will be provided for the communication element. As another example, referring to the embodiment in fig. 2A and 2B, the pattern may define where to provide the RFID device with the antenna 224. In another embodiment, the pattern may define where to provide inductive or capacitive signal communication elements for a variety of wireless devices.

At step 340, the VSD material is triggered or converted from a dielectric state to a conductive state. A voltage can be applied to the VSD material that exceeds a material characteristic level. The voltage may be applied to a thickness layer comprising VSD material or to a portion of the substrate underlying the VSD material. In the latter case, the portion of the substrate underlying the VSD material may be conductive (e.g., formed of copper or other metal) to carry charge onto the VSD material. The voltage applied to the conductive substrate may be required in some cases to avoid linear conductivity of the VSD material in the direction of the substrate. The applied voltage may be stable (e.g., "DC") or pulsed.

When the VSD material is conductive, step 350 provides for performing an ion deposition process within the exposed areas of the pattern to form conductive elements (e.g., lines). Any of a number of processes may be used to deposit the ionic medium to the exposed areas defined by the non-conductive layer pattern. In one embodiment, an electroplating process is performed in which the substrate with VSD material and patterned photoresist material is immersed in an electrolyte.

As an alternative implementation, ion deposition is performed using a powder coating painting process. In this process, the powder particles are charged and applied to the exposed areas defined by the pattern. The application of the powder may be achieved by depositing the powder onto the exposed areas or dipping the substrate into a powder bath.

Further, yet another embodiment may use an electrospray process. The ionic vehicle may be contained in the solution in the form of charged particles. The solution can be applied to the substrate while the VSD material is conductive. The application of the spray may include the use of ink or paint.

Other deposition techniques may also be used to perform ion deposition onto the VSD material while the VSD material is in a conductive state. For example, a vacuum deposition process such as Physical Vapor Deposition (PVD) or Chemical Vapor Deposition (CVD). In PVD, metal ions are introduced into a chamber to mix with gas ions. The VSD material located on the substrate can be made conductive, having a positive charge, to adsorb and bind ions within the cavity. In CVD, a thin layer of ionic material may be applied to the VSD material on the surface of the substrate.

At step 760, the non-conductive material is (optionally) removed from the substrate, leaving the formed conductive elements. In one embodiment, a base solution (e.g., KOH) or water is applied to the substrate to remove the photoresist material. The conductive elements may correspond to leads, traces, and other elements positioned to interconnect various components and/or regions of the substrate.

Following removal of the layer of photoresist material, one or more embodiments provide a step performed on the substrate to polish the formed electrical components. In one embodiment, chemical mechanical polishing is used to polish the substrate.

The resulting substrate includes electrical components with inherent capability to handle transient voltages and EOS. For a wireless communication device, a line element may be formed using a process as described in fig. 3, including an antenna or communication element of the device, as well as other elements or components. Once the substrate is formed, devices such as microchips, memory components, and other devices are mounted onto the circuit board in predetermined locations that coincide with the pattern of conductive components and elements.

Other steps may be performed depending on the application, for example, the substrate with the conductive elements may be incorporated into a package. The package itself may also include additional VSD material. The resulting device may correspond to a transmitter for radio frequency signals, microwaves, or signals for capacitive/inductive applications.

Fig. 4A-4E illustrate a process for forming an RFID device in accordance with one or more embodiments of the present invention. To form VSD material integrally with the electrical components and elements of the LED device, a process as described in fig. 4A-4E can be performed. Among other advantages, the application of VSD material simplifies the process of forming the RFID device while at the same time, providing the electrical components and elements of the RFID device with inherent ability to handle transient voltages and EOS. In particular, the integration of VSD material into the electrical components of the LED substrate can enable the VSD material to ground the device in the presence of transient voltages (e.g., when an ESD event occurs).

In the step illustrated by FIG. 4A, substrate 410 is formed to include VSD material 412 in one implementation, VSD material 412 is deposited as a layer overlying backing substrate 408.

Subsequently, fig. 4B shows a step in which a non-conductive layer 420 is deposited onto the substrate 410. The non-conductive layer 420 may correspond to, for example, a photoresist material.

In one step shown in fig. 4C, the non-conductive layer is patterned to form exposed regions 430. As a result of the described forming process, the resulting pattern corresponds to the pattern of conductive elements and components to be provided on the RFID device.

In one step depicted in fig. 4D, conductive elements 440 are formed above exposed regions 430, which exposed regions 430 are defined by the pattern formed in one step of fig. 4C. According to one embodiment, a voltage is applied to the substrate that exceeds the characteristic voltage of the VSD material 412. Application of this voltage causes the VSD material 412 to transition from a dielectric state to a conductive state. Once the VSD material 412 becomes conductive when a voltage is applied, ionic media is deposited within the exposed areas defined by the pattern to form electrical elements and components.

In one embodiment, the ionic medium deposition is performed by an electroplating process. During this electroplating process, the substrate 410 is immersed in an electrolyte in which ionic media from the solution bonds with the VSD material (which is in a conductive state) in the pattern-defined exposed areas. The result of this step is that conductive material 440 is formed on the substrate 410, and VSD material 412 is located underneath the conductive elements or features resulting from the formation of conductive material 440.

As described for the embodiment of fig. 3, the underlying substrate 408 may be formed of a conductive material, such as a metal. Instead of applying a voltage directly to the VSDM material 412, a voltage may be applied at a contact coincident with the substrate 408. For example, the voltage may be provided below the substrate 408. With such voltage application, linear (i.e., horizontal) conductivity across, for example, the VSDM material can be avoided.

As mentioned, the applied voltage may be either stable or pulsed.

Other ion media deposition processes may be performed. For example, as described for the embodiment of FIG. 3, a powder coating process may be used to deposit charged powder particles into the pattern-defined exposed areas. Alternatively, electrospray may force ionic media in a liquid to combine and form electrical material in pattern-defined exposed areas.

In one step of fig. 4E, the non-conductive layer 420 is removed and the conductive elements 440 on the substrate are polished or reduced to form some or all of the traces, leads, and RFID device components. In some applications where it is desirable to leave non-conductive layer 420, non-conductive layer 420 may not be removed.

Fig. 4E shows how the components and elements of the RFID device are formed under the described process. In one embodiment, the VSD material 412 is integrated with and located below a wiring element, such as (i) an antenna 474 forming the RFID device, and (ii) an extended conductive connecting element 476 formed between the microchip 492 and the antenna 474

One or more embodiments may also provide that the VSD material 412 is located below the line element below the battery 494 or below the line element 478, the line element 478 carrying power from the battery 494 to the antenna 474 and/or microchip 492.

One embodiment as depicted in figures 4A-4E allows for the creation of electrical components and elements within an RFID device that covers VSD material, and thus includes the inherent ability to ground transient voltages that may be generated as a result of ESD. The RFID may also be made with fewer processing steps than more conventional techniques.

While the embodiments described in figures 4A-4E and elsewhere in this disclosure, etc., describe the use of VSD material, one or more embodiments provide for the use of VSD material of different compositions and configurations on a single RFID device. For example, application of VSD material 412 to a substrate (fig. 4A) may include application of multiple VSD materials, each having a different composition. This allows the design of RFID devices to utilize VSD material having mechanical or electrical characteristics that are most appropriate for a particular electrical component or element. For example, it may be desirable to provide VSD material in the area near the battery of the RFID device with a characteristic voltage level that is higher than the voltage of the area near microchip 492 because the microchip may be more sensitive to inrush currents or the battery may provide a larger voltage spike.

Other components that may be provided on the substrate include light emitting devices, such as LEDs and OLEDs. As described in U.S. provisional patent application No. 60/740,961, LEDs and OLEDs may also be sensitive to breakdown due to transient voltages. In one or more embodiments, a wiring member formed on the substrate is provided to provide leads and interconnection elements to the light emitting device. The VSD material selected for use may have a characteristic voltage level that is lower than the levels of conductive elements and components of both the RFID device and the light emitting device.

While fig. 4A-4E specify the creation of RFID devices, any of the wireless communication devices described in connection with other embodiments of the application may be created or formed, in part, by a process such as that described in fig. 4A-4E. For each alternative application, the location of the conductive elements and features may determine the pattern of the photoresist (or non-conductive layer).

Further, the wireless communication device may be multi-dimensional in view of any of the described embodiments. For example, components for an RFID device or other communication element may be incorporated on both sides of a substrate and conductively interconnected using one or more vias. Alternatively, the preparation of the conductive vias may be performed in any conventional technique. Alternatively, one or more embodiments provide for forming vias on a substrate as shown in the embodiments of fig. 4A-4E as follows: (i) drilling or forming a hole 409 extending through the base 408 (fig. 4A); (ii) extending the VSD material into the via 409 when the VSD material is applied; (iii) when the photoresist material is molded, it is patterned to form a path for the conductive line elements to extend to the boundaries of the aperture 409; and (iv) performing ion deposition to render the via surface conductive, forming a conductive or operable via 419, and (v) repeating said steps to arrange electrical elements and components on opposite sides of the substrate. The process of using VSD material to form plated through holes 419 is described in more detail in U.S. patent 6,797,145, which is incorporated by reference herein in its entirety.

In addition to the double-sided substrate, vias can extend conductivity to multiple conductive layers to obtain a properly designed substrate. For example, some substrates include intermediate thickness layers that contain electrical components and elements. The vias may extend to connect such intermediate thickness layers embedded in the entire thickness layer of the substrate.

Alternative embodiments and implementations

Although the embodiments herein are provided for devices (wireless communication devices, RFID tags), embodiments may also include antennas, or capacitive or inductive field elements, formed using VSD material. Such communication components may be incorporated into devices such as chipsets and RFID tags, independently of the formation of the rest of the device. For example, the antenna of the RFID tag may be formed as a separate part and combined with the RFID tag in the assembly step.

General summary

Although illustrative embodiments of the invention have been described in detail herein, it should be understood that the invention is not limited to those precise embodiments. Also, many modifications and variations will be apparent to practitioners skilled in the art. Accordingly, the scope of the invention should be determined by the following claims and their equivalents. Furthermore, it is contemplated that a particular feature described herein, either individually or as part of an embodiment, may be combined with other individually described features or parts of other embodiments, even if the other features and embodiments do not recite that particular feature. The mere fact that certain measures are recited in mutually different dependent claims does not exclude the presence of other measures.

Claims (26)

1. A wireless communication device, comprising:

a combination of conductive elements configured to enable wireless transmission or reception of signals; and

a material having a property that transitions from dielectric to conductive when a voltage is applied to the material that exceeds a characteristic voltage level, and wherein the material is positioned to ground at least a portion of the device when subjected to a voltage that exceeds the characteristic voltage level.

2. The apparatus of claim 1, wherein the material is positioned to ground the combination of conductive elements when subjected to a voltage exceeding the characteristic voltage level.

3. The apparatus of claim 1, further comprising:

a substrate, and

one or more logic elements provided on the substrate.

4. The device of claim 3, wherein the material is provided on the substrate to ground at least one of the one or more logic elements when encountering a voltage that exceeds the characteristic voltage level.

5. The apparatus of claim 4, wherein a combination of conductive elements is provided over the substrate, and wherein the material is provided on the substrate to ground at least a portion of the combination of conductive elements when subjected to a voltage exceeding the characteristic voltage level.

6. The device of claim 1, further comprising a package encapsulating the combination of conductive elements, wherein the package comprises the material.

7. The apparatus of claim 6, wherein the material is provided as at least one of: (i) a layer on a portion of the package, or (ii) an adhesive for bonding one or more portions of the package or a component thereof.

8. A wireless communication device, comprising:

a substrate;

one or more logic elements provided on the substrate, wherein the one or more logic elements generate data including identification information about the device;

a transmit component provided on the substrate, wherein the transmit component is configured to generate a signal, said signal carrying identification information from the one or more logic elements; and

a material having a property that transitions from dielectric to conductive when a voltage is applied to the material that exceeds a characteristic voltage level, and wherein the material is positioned to ground at least a portion of the device when subjected to a voltage that exceeds the characteristic voltage level.

9. The apparatus of claim 8, further comprising a package including the one or more logic elements and the transmit part, and wherein the material is provided within the package.

10. The device of claim 9, wherein the characteristic voltage level of the material exceeds an operating voltage level of the device.

11. The apparatus of claim 8, wherein the material is applied or incorporated as part of the substrate.

12. The apparatus of claim 11, wherein at least one of the transmit component or the one or more logic elements is disposed over the substrate to cover at least a portion of the material.

13. The apparatus of claim 12, wherein at least one of the transmitting element or the one or more logic elements is disposed on the substrate to cover the material by applying a voltage to the material that makes the material conductive while performing an electroplating process to include elements formed on the material.

14. The apparatus of claim 12, wherein the emitting component comprises a set of conductive traces, and wherein at least a portion of the set of conductive traces is positioned to cover the material.

15. The device of claim 12, wherein the device comprises a conductive element arranged to interconnect the one or more logic elements and the transmission component, and wherein at least a portion of the interconnect element is disposed on the substrate to cover at least a portion of the material.

16. The device of claim 8, wherein the package includes a top layer and a bottom layer, and wherein the material is provided as an adhesive between the top layer and the bottom layer.

17. The apparatus of claim 8, wherein at least one of the transmission component or the one or more logic elements is combined with or in contact with the material.

18. The device of claim 8, wherein the device further comprises a power source and a power connection element extending conductivity between the power source and at least one of the transmission component or the one or more logic elements, and wherein at least one of the power source or the power connection element is combined with or in contact with the material.

19. The device of claim 8, wherein the device further comprises a power source and power connection elements extending conductivity between the power source and at least one of the transmission component or the one or more logic elements, and wherein at least one of the power source or power connection elements is disposed on the substrate to cover at least a portion of the material.

20. The apparatus of claim 18, wherein the power source is a receiver for receiving an applied external power signal.

21. A method for forming a wireless communication device, the method comprising:

forming a substrate to include a layer of material, wherein the material has a property of transitioning from dielectric to conductive when a voltage is applied to the material that exceeds a characteristic voltage level;

forming a layer of resistive material over the layer of material;

selectively removing the resistive material to pattern exposed areas on the layer of resistive material, wherein the exposed areas are located under any one or more of: (i) one or more logic elements to be embedded in the device, (ii) an antenna element, (iii) an interconnection element between the one or more logic elements and the antenna element, (iv) a power source, or (v) an interconnection element between the power source and the one or more logic elements or the antenna element;

applying a voltage exceeding the characteristic voltage to the material having the resistive material layer and the pattern; and

when the voltage is applied, an ionic medium is applied to the substrate to form a conductive element on the voltage variable material in at least a portion of the exposed region that is molded onto the substrate.

22. The method of claim 21, wherein applying an ionic medium to the substrate comprises performing one of:

(i) an electroplating process in which the substrate is immersed in an electrolyte;

(ii) a powder coating application process in which charged powder particles are applied to exposed areas of the substrate;

(iii) an electrospray process in which an ion spray is applied to the substrate; or

(iv) A vapor deposition process.

23. A wireless communication device, comprising:

a package;

a substrate provided within the package;

wherein the substrate is formed as follows:

providing a substrate comprising a layer of material, wherein the material has the property of transitioning from dielectric to conductive when a voltage is applied to the material that exceeds a characteristic voltage level;

forming a layer of resistive material over the layer of material;

removing the resistive material to form a pattern on the layer of resistive material;

applying a voltage exceeding the characteristic voltage to the material having the resistive material layer and the pattern;

applying an ionic medium to at least a portion of the substrate while the voltage is applied to form a conductive element on the substrate at a location where at least a portion of the pattern is provided;

one or more logic elements provided on the substrate, wherein the one or more logic elements generate data, the data including identification data;

a transmitting element provided on the substrate, the element generating a signal, said signal carrying the identification information;

one or more interconnect elements extending conductivity between the one or more logic elements and the transmit section;

wherein at least one of the logic element, the transmission element or the interconnect element uses a conductive element formed on a substrate.

24. The apparatus of claim 23, further comprising a power source, and one or more power connection elements extending conductivity between the power source and at least one of the transmission component or the one or more logic elements.

25. The apparatus of claim 23, wherein at least one of the power source or the power connection element uses a conductive element formed on the substrate.

26. The apparatus of claim 25, wherein the power source is a receiver for receiving an applied external power signal.