Functional substrates for printed electronic devices

A circuit device formed from a functional substrate. The circuit device comprises a functional substrate component and printed electronic elements formed on the functional substrate component. The printed electronic elements formed on the functional substrate component interact with the substrate component to perform a function and to modify the functional substrate component. The circuit device typically needs a passive base material that takes no functional part in the device operation except mechanical support.

BACKGROUND

The present invention relates generally to a circuit device formed from a functional substrate component. Specifically, the substrate exhibits properties designed to interact with the printed electronics to perform a function beyond mechanical support.

Printed or vacuum formed electronics are increasingly finding uses in a great variety of applications, including portable electronics, signage, lighting, product identification, packaging flexible electronic devices (such as those that can be rolled or bent), photovoltaic devices, medical and diagnostic devices, antennas (including RFID antennas), displays, sensors, thin-film batteries, electrodes, etc. Printed electronics have a variety of advantages over electronics made using other methods, including their use in flexible devices, such as displays, that are designed to be rolled, twisted, or bent.

Typically, printed or vacuum formed electronic devices are formed on a substrate to support them during processing. The substrate is typically comprised of materials such as glass or metals. These materials are passive, in that they take no functional part in the device operation except mechanical support. However, sometimes it is necessary or at least desired for the substrate, or an initial layer formed on it, to be functional, in that the substrate exhibits properties designed to interact with the electronics to perform a function beyond mechanical support.

Accordingly, the present invention discloses a circuit device formed from a functional substrate component. The printed electronic elements formed on the functional substrate component interact with the substrate component to perform a function and to modify the functional substrate component.

SUMMARY

The subject matter disclosed and claimed herein, in one aspect thereof, comprises a circuit device formed from a functional substrate. The circuit device comprises a functional substrate component and printed electronic elements formed on the functional substrate component. The printed electronic elements formed on the functional substrate component interact with the substrate component to perform a function and to modify the functional substrate component. The circuit device typically needs a base material, such as glass, stainless steel, or plastics. The base material may or may not be removed once the circuit device has been constructed. The base material would be passive, in that it takes no functional part in the device operation except mechanical support.

In another embodiment, the circuit device comprises a surface acoustic wave (SAW) device which is designed to act as a frequency stabilizing element in an oscillator, in conjunction with an amplifier. The oscillator is controlled by a logic circuit component formed on the substrate component. The logic circuit component activates and modulates the oscillator in conjunction with an antenna to transmit or receive information.

In another embodiment, the circuit device comprises a functional substrate component comprising magnetic material. The electronic components comprise coils that exhibit magneto resistance and that interact with magnetic areas in the substrate component. The circuit device then acts as a form of storage of information, such as digital bits. The magnetic material of the substrate component can also function as a magnetic strip. This interaction allows the magnetic strip to be modified by the circuit as well as the state to be read.

DETAILED DESCRIPTION

A circuit device is disclosed that is formed from a functional substrate in that it has properties designed to interact with the electronics to perform a function beyond mechanical support. The circuit device comprises a functional substrate component and printed electronic elements formed on the functional substrate component. The printed electronic elements formed on the functional substrate component interact with the substrate component to perform a function and to modify the functional substrate component.

Besides the well-known methods of creating circuit blocks, the circuit devices100can be used in a number of alternative methods, as well. For example, transistors, diodes, and memory cells on a silicon wafer have been experimented with and functional devices, such as display drivers and low frequency RFID devices have been created. Materials used in these devices100include organic semiconductors, such as those based on polyanilines, amorphous silicon, and metal oxides.

Referring initially to the drawings,FIG. 1illustrates a circuit device100with printed electronic elements102formed on the functional substrate component104. Specifically, the circuit device100can be any suitable size, shape, and configuration as is known in the art without affecting the overall concept of the invention. One of ordinary skill in the art will appreciate that the shape and size of the circuit device100as shown inFIG. 1is for illustrative purposes only and many other shapes and sizes of the circuit device100are well within the scope of the present disclosure. Further, although dimensions of the circuit device100(i.e., length, width, and height) are important design parameters for good performance, the circuit device100may be any shape or size that ensures optimal performance and sensitivity during use.

Typically, the functional substrate component104comprises piezoelectric, magnetic, or dielectric properties which interact with the printed electronic elements102to perform a function. The functional substrate component104is modified108by one or more of the steps used in fabricating the electronic elements102to allow interaction. The electronic elements102are commonly referred to as ‘printed’, although other methods such as vacuum deposition, etching, or any other suitable methods as is known in the art, can be used to create electronic circuits on a functional substrate104. Printed electronics102are typically made by printing the electronic circuit or other component or device on a substrate using an electrically conductive metal-based ink.

Generally, the circuit devices100require a base material106for them to be built on, such as glass, stainless steel, or plastics such as polyimides, polyethylene tetraphalate, or any other suitable base material as is known in the art. This base material106may or may not be removed once the circuit device100construction has been completed. However, this base material106would be described as passive as it takes no functional part in the circuit device100operation except mechanical support.

One exemplary embodiment of how a functional substrate104can be combined with an electronic circuit component102formed on the surface of the substrate104to create the circuit device100is shown in the transmitter200ofFIG. 2A, wherein a Surface Acoustic Wave (SAW) device202is designed to act as the frequency stabilizing element in an oscillator. A SAW device202is a well-known device that is functional at high frequencies, based on the propagation of acoustic waves in the surface of a suitable substrate208, such as quartz or lithium niobate. The SAW device202can also perform functions such as frequency control, filtering and sensing. These SAW devices202are used extensively in items such as cellular phones. The SAW devices202are also commonly formed by a deposition of a metal, such as aluminum, onto the substrate and formation of a defined pattern in that layer.

In this embodiment, the SAW device202is designed to act as the frequency stabilizing element in an oscillator, in conjunction with an amplifier204, such as one or more transistors (or other suitable device as is known in the art) operating in the required frequency. The oscillator is controlled by a logic circuit206built onto the quartz or lithium niobate substrate208. This circuit206can activate the oscillator but also modulate it, so that, in conjunction with an antenna210formed either on the substrate208or external to the substrate208, the device can transmit information, such as codes stored inside the logic or data derived from a sensor. Power for the circuit can either be derived by energy harvesting, or optionally using the piezoelectric properties of the base, from a battery212, either on the substrate208or externally.

FIG. 2Bshows an alternative embodiment of a transmitter/receiver device214. The alternative transmitter/receiver device214incorporates both receiving and transmitting functions, as well as, optionally, a filter216. This transmitter/receiver device214can be used to establish bidirectional communications with other systems. For example, the transmitter/receiver device214can act as a Bluetooth transceiver, an access point for a WiFi system, or, in a preferred embodiment, an RFID reader.

The functional substrate component218of this embodiment is typically manufactured of quartz, lithium niobate, or other suitable substrate materials as is known in the art. Logic and/or RF electronics220are positioned on the substrate component218to interact with the SAW resonator222for frequency control. The SAW filter216in conjunction with an antenna224formed either on the substrate218or external to the substrate218allows the device to transmit and receive information, such as codes stored inside the logic or data derived from a sensor, as well as establish bidirectional communications with other systems.

FIG. 3illustrates an alternative structure of an acoustic sounder device300wherein the functional substrate302is a piezoelectric plastic film or ceramic. The electronics304formed on the surface can cause the device300to emit sonic and/or ultrasonic signals, and may also receive them as required. Typical applications would be the emission of sounds associated with promotional activities, greeting cards, etc.

The substrate302is typically a piezoelectric plastic film, such as PVDF, wherein drive electronics304are formed on the surface. The drive electronics304interact with a top conductor306as well as a base conductor308to cause the device300to emit and/or receive sonic and/or ultrasonic signals.

FIG. 4Aillustrates an alternative structure400wherein the substrate402is a magnetic material, such as an iron oxide, steel or materials based on other magnetic metals when in their oxide state. Then, electronic components404such as coils or other devices exhibiting magneto resistance can interact with the magnetic areas in the substrate402as well as the read/write points406, which then acts as a form of storage of information. This device may then store digital bits, which are used to control the actions of the electronic circuit404, and data, such as identifying information for an RFID chip.

Further, as the magnetic storage is not inherently binary, analogue values may be stored, which, when sequentially addressed, can be samples of an analogue waveform such as speech or music, which can be played out to a speaker; such analogue values can also playback device to be realized.

In an alternative structure500,FIG. 4Bshows active electronic components502formed on a magnetic substrate504, where the magnetic material of the substrate504functions as a magnetic strip506. Specifically, read/write points508from the electronic circuit502interact with the magnetic strip506. This interaction allows the magnetic strip506to be modified by the electronic circuit502as well as the state to be read. This interaction may be used in an RFID device designed to be interoperable between both magnetic strip type read/write devices and RFID read/write devices.

In the cases where a magnetic material is used as a base substrate, the high permeability can be used to increase the inductance of coils formed on the surface, allowing them to resonate with a capacitor at lower frequencies than would otherwise be possible.