HYBRID DOCUMENTS WITH ELECTRONIC INDICIA

A hybrid document includes a flexible document having visible markings. One or more light-controlling elements and a controller are embedded in or on the flexible document. The controller is electrically connected to the one or more light-controlling elements to control the one or more light-controlling elements. A power input connection is electrically connected to the controller, or one or more light-controlling elements, or both. A power source can be connected to the power input connection, for example a piezoelectric or photovoltaic power source. In response to applied power, the controller causes the one or more light-controlling elements to emit light. In some embodiments, the controller includes a memory and a value can be stored in the memory and displayed by the light-controlling element(s). In some embodiments, the value can be assigned or varied by a hybrid currency teller machine.

CROSS REFERENCE TO RELATED APPLICATIONS

This patent application is related to U.S. patent application Ser. No. 16/181,294 entitled Hybrid Banknote with Electronic Indicia, filed Nov. 5, 2018, which is a continuation of U.S. Pat. No. 10,150,325 entitled Hybrid Banknote with Electronic Indicia, filed Feb. 15, 2016, the disclosure of each of which is hereby incorporated by reference herein in its entirety.

TECHNICAL FIELD

The present disclosure relates to currency and particularly to banknotes having electronically controlled inorganic light-emitting diodes embedded in the banknotes.

BACKGROUND OF THE DISCLOSURE

Monetary instruments issued by governments such as money or currency are used throughout the world today. Government-issued currency typically includes banknotes (also known as paper currency or bills) having visible markings printed on high-quality paper, plastic, or paper impregnated with other materials, such as plastic. The visible markings indicate the denomination (value) of the banknote, includes a serial number, and has decorations such as images, and anti-counterfeiting structures such as special threads, ribbons, and holograms. Currency circulates within an economic system as a medium of monetary exchange having a fixed value until it is physically worn out. Worn out banknotes are generally returned by banks or other financial institutions and then replaced.

Other privately issued monetary instruments are also used, such as credit cards and gift cards. These cards typically include an electronically accessible value (e.g., stored in a magnetic stripe or in a chip in the card) or an electronically accessible account that can be used to make purchases. However, the value or validity of the card is not readily viewed by a user without special equipment, such as a reader.

In the past, banknotes have not been electronically enabled. However, more recently there have been proposals to use RFID (radio-frequency identification device) in banknotes to validate the banknote and avoid counterfeiting. For example, U.S. Pat. Nos. 8,391,688 and 8,791,822 disclose systems for currency validation. U.S. Pat. No. 5,394,969 describes a capacitance-based verification device for a security thread embedded within currency paper to defeat counterfeiting. Security systems for scanning a paper banknote and checking identification information in the banknote (e.g., the serial number) with a network-accessible database have been proposed, for example in U.S. Pat. No. 6,131,718. In all of these systems, however, there is no way to visibly and electronically or optically validate a banknote without using a separate electronic or optical reader.

There remains a need therefore, for currency providing validation that is electronically accessible with visible indicia without using a separate electronic or optical reader.

SUMMARY OF THE DISCLOSURE

The present disclosure provides a hybrid currency banknote having visible markings and one or more light-controlling elements, for example inorganic light-emitting diodes (iLEDs), and a controller embedded in or on the banknote and electrically connected to control the light-controlling elements to emit light. A power input connection is electrically connected to the controller, or one or more light-controlling elements, or both. In a further embodiment, a power source, such as a piezoelectric or photovoltaic device, is electrically connected to the power input connection, with or without a power convertor. In various embodiments, the visible markings include printed images or value indicators. The light-controlling elements can form a graphic indicator such as a number, letter, or pictogram or can highlight a visible marking on the banknote. The light-controlling elements can form a display, for example a monochrome or full-color display.

In one embodiment, the light-controlling elements or controller are printed on the pre-printed banknote. In another embodiment, the light-controlling elements or controller is printed on a ribbon or thread that is subsequently woven or otherwise incorporated into the banknote. The ribbon or thread can also include electrical conductors to electrically connect the controller, the light-controlling elements, and the power source in a circuit. When operated by applying power, the controller controls the light-controlling elements to emit light, for example in a spatial pattern, or in a temporal pattern (for example with flashing lights or sequentially flashing lights), or both. Different light-controlling elements30can be activated in response to sequential squeezes of the piezoelectric power source60.

The currency can also include light pipes (optical waveguides) arranged in association with the light-controlling elements. The light pipes can conduct light to desired locations on the banknote or can form patterns such as graphic indicators. The light pipes can include light-emitting portions, for example diffusers, along the length of the light pipes to emit light at locations along the length of the light pipe as well as at the end of the light pipe.

The controller can include a memory, for example a read-only memory or a write-once memory storing one or more values and the light-controlling elements can be controlled to display numerals corresponding to the values. Multiple values can be stored in a sequential order corresponding to a temporally sequential set of values and can monotonically decline in magnitude. Values stored in the banknote can be electronically read by a teller machine having a reader and the value of the banknote displayed on the teller machine. In a further embodiment, the teller machine can write a value to the banknote using a writer. In some embodiments, the controller controls the written value so that it must be equal to or smaller than a value already stored in the banknote.

A method of making a hybrid currency banknote includes providing a banknote having visible markings, a wafer having a plurality of micro-transfer printable light-controlling elements, and a wafer having a plurality of controllers. One or more of the light-controlling elements and at least one controller are embedded in the banknote, for example by micro-transfer printing onto the banknote or onto a thread or ribbon that is subsequently incorporated into the banknote. The controller is electrically connected to the one or more light-controlling elements and to a power input connection. A power source can also be provided, for example by micro-transfer printing the power source on the banknote or ribbon. An issuer of the hybrid currency banknote can provide a memory with a value or write the value to a memory in the banknote to provide the banknote with a value.

The hybrid currency banknote of the present disclosure can be used by receiving the banknote and providing power to the power input connection, for example by a teller machine that then displays the value of the banknote on the banknote itself or on a display incorporated into the teller machine. Alternatively, the banknote includes a piezoelectric power source and upon squeezing the power source the controller controls the light-controlling elements to emit light. In another embodiment, the banknote includes a photovoltaic power source and upon exposure to electromagnetic radiation (such as infrared or ultraviolet radiation), the controller controls the light-controlling elements to emit light.

A user can insert a received banknote into a teller machine, input an input value to the teller machine, and the teller machine can write a value derived from the input value into the banknote. The input value can represent the value of a monetary transaction, for example a purchase of goods or payment of debt and the difference between the input value and the current value can be written into the hybrid currency banknote.

According to some embodiments of the present disclosure, a hybrid document comprises a flexible document having visible markings and a component embedded in or on the flexible document or in or on a ribbon or thread incorporated into the flexible document. The component comprises a component substrate, one or more relatively rigid inorganic light-emitting diodes disposed on the component substrate, a controller disposed on the component substrate and electrically connected to the one or more inorganic light-emitting diodes for controlling the one or more inorganic light-emitting diodes, and a power input connection electrically connected to (i) the controller, (ii) the one or more inorganic light-emitting diodes, or (iii) both (i) and (ii).

According to some embodiments, the component comprises a power convertor disposed on the component substrate connected to the power input connection and the controller or the one or more inorganic light-emitting diodes to convert the power provided from the power input connection to a form that is used by the controller or the inorganic light-emitting diodes. The power convertor can comprise (but is not limited to) a unitary capacitor, a disaggregated capacitor comprising multiple capacitors electrically connected in parallel, a diode, or any one or combination of these.

The one or more inorganic light-emitting diodes can each comprise a fractured or separated tether, the controller (or power convertor) can comprise a fractured or separated tether, the component or component substrate can comprise a fractured or separated tether, or any one or combination of these. Fractured or separated tethers can be a consequence of micro-transfer printing.

In some embodiments, the power source is provided in the component, for example on the component substrate. In some embodiments, the power source is provided external to the component, for example on the flexible document. The power source can be a photovoltaic power source, an electromagnetic energy harvester, for example comprising an antenna or photodiode or other photosensor, a piezoelectric power source activated by pressure, or a piezoelectric power source activated by movement. The power source or component can be indicated by the visible markings, the power source or component can form a part of the visible markings, or the power source or component can be obscured by the visible markings. In some embodiments, the component is disposed in a location corresponding to a portion of the visible markings to indicate (e.g., highlight) the portion of the visible markings. The controller controls the one or more-inorganic light-emitting diodes to flash or flash sequentially.

In some embodiments, the power source comprises a plurality of electrically connected individual power source components. In some embodiments, the power convertor comprises a plurality of electrically connected individual power convertor components.

The flexible document can be a government-issued banknote indicated by the visible markings. In some embodiments, the hybrid document is a banknote, a bond, a stock certificate, a commercial certificate, a printed value-bearing document, an identification document, or a government-issued document. The flexible document can include a flexible substrate that includes paper, plastic, or impregnated paper, and the component and component substrate can be printed (e.g., micro-transfer printed) on the flexible substrate. In some embodiments, the flexible document comprises a ribbon or thread woven into the flexible document and the component is disposed on the ribbon or thread. The ribbon or thread or portions of the ribbon or thread can be at least partially electrically conductive or include conductive wires.

According to some embodiments, a plurality of components are disposed on the flexible document in a random arrangement or in a regular array. Each of the plurality of components can include a component substrate, one or more relatively rigid inorganic light-emitting diodes disposed on the component substrate, a controller disposed on the component substrate and electrically connected to the one or more inorganic light-emitting diodes for controlling the one or more inorganic light-emitting diodes, and a power input connection electrically connected to (i) the controller, (ii) the one or more inorganic light-emitting diodes, or (iii) both (i) and (ii). In some embodiments, (i) each of the one or more inorganic light-emitting diodes comprises a fractured or separated tether, (ii) the controller comprises a fractured or separated tether, (iii) the component substrate comprises a fractured or separated tether, or (iv) any one or combination of (i), (ii), and (iii)

According to some embodiments of the present disclosure, a method of making a hybrid document comprises providing a flexible document having visible markings, providing a light-emitting diode source wafer having a plurality of relatively rigid printable inorganic light-emitting diodes connected by light-emitting diode tethers to the light-emitting diode source wafer, providing a controller source wafer having at least a portion of a plurality of controllers connected by controller tethers to the controller source wafer, providing a component substrate, and printing at least a portion of at least one or a portion of the plurality of controllers, power convertors, and one or more of the plurality of inorganic light-emitting diodes from the controller source wafer, a power convertor source wafer, and the light-emitting diode source wafer, respectively, to the component substrate, thereby fracturing or separating each light-emitting diode tether that connected the one or more of the plurality of inorganic light-emitting diodes to the light-emitting diode source wafer, each controller tether that connected the at least one of the plurality of controllers to the controller source wafer, and each power convertor tether that connected the at least one of the plurality of power convertors to the power convertor source wafer to provide a component, printing the component in or on the flexible banknote or in or on a ribbon or thread (e.g., thereby embedding the component in or on the flexible banknote or in or on the ribbon or thread), and electrically connecting the at least one of the plurality of controllers to the one or more of the plurality of inorganic light-emitting diodes and to a power input connection. In some embodiments, the power convertor is the controller or the controller is the power convertor in a single device or electrical circuit. Either the power convertor or controller can comprise multiple circuit elements.

In some embodiments, methods of the present disclosure comprise providing a component wafer having relatively rigid component substrates. The relatively rigid component substrates can be connected by component tethers to the component wafer and the method can comprise printing the components after printing the at least one of the plurality of controllers and the one or more of the plurality of inorganic light-emitting diodes to the component substrate.

In some embodiments, the at least one of the plurality of controllers is electrically connected to the one or more of the plurality of light-emitting diodes before the component is printed in or on the flexible banknote or the ribbon or thread. In some embodiments, the at least one of the plurality of controllers is electrically connected to the one or more of the plurality of light-emitting diodes after the component is printed in or on the flexible banknote or the ribbon or thread.

According to some embodiments of the present disclosure, a hybrid document comprises a document and a component. The component can comprise a power component disposed on or in the document, a controller disposed in or on the document and electrically connected to the power component, and a light-emitting diode (LED) (e.g., an inorganic light-emitting diode (iLED)) disposed in or on the document. The controller can be an integrated circuit or can be a simple circuit comprising a diode, rectifier, or bridge circuit with or without capacitors. The power component can comprise a power support and a piezoelectric cantilever extending from the power support. The piezoelectric cantilever can comprise a layer of piezoelectric material, a first electrode on a first side of the piezoelectric material and a second electrode on a second side of the piezoelectric material opposite the first side. In some embodiments, the power component, the controller, and the inorganic light-emitting diode are comprised in a circuit that emits light from the inorganic light-emitting diode in response to power received from the power component. According to some embodiments, the document has a document surface and any one or combination of the circuit, the power component, the controller, and the inorganic light-emitting diode can comprise a component that is disposed on the document surface.

According to some embodiments of the present disclosure, the piezoelectric cantilever extends in a cantilever plane that is non-orthogonal to a surface of the document and the piezoelectric cantilever is operable to oscillate in a direction non-parallel to the cantilever plane. The cantilever plane can be substantially or desirably parallel to a surface of the document and the piezoelectric cantilever can oscillate in a direction substantially or desirably orthogonal (e.g., perpendicular) to the cantilever plane.

According to some embodiments, the hybrid document or component comprises a component substrate disposed on the document and the power component, the controller, and the inorganic light-emitting diode are each disposed on or in the component substrate. A plurality of power components can be disposed on the component substrate. In some embodiments, the document is flexible or is more flexible than the component or the component substrate. In some embodiments, the component substrate comprises a fractured or separated component tether.

According to some embodiments of the present disclosure, the piezoelectric cantilever is disposed over or in a cavity in the component substrate. The cavity can be enclosed, for example with a cap. The component can comprise an encapsulation layer disposed around the cavity such that the cavity is enclosed at least by the encapsulation layer.

In some embodiments of the present disclosure, the hybrid document comprises a plurality of components disposed on the document. Each component can comprise a respective component substrate and a respective circuit. Each circuit comprises at least a respective light-emitting diode, a respective controller, and a respective power component. Each circuit is disposed on a different component substrate and each component substrate is independent and separate from any other component substrate of any other component and is disposed on the document surface.

According to some embodiments, the piezoelectric cantilever is disposed over a cavity in the component substrate.

The hybrid document can be a banknote.

According to embodiments of the present disclosure, (i) the controller comprises a fractured or separated controller tether, (ii) the inorganic light-emitting diode comprises a fractured or separated LED tether, or (iii) any one or combination of (i) and (ii).

According to some embodiments, the circuit comprises a capacitor electrically connected to the power component such that power transmitted from the power component is stored in the capacitor and subsequently discharged to cause the light-emitting diode to emit the light. In some embodiments, the hybrid document comprises a plurality of inorganic light-emitting diodes connected to the circuit and disposed on the document.

In some embodiments, the piezoelectric cantilever and the capacitor comprise a same dielectric material disposed in a common layer.

In some embodiments, the inorganic light-emitting diode is disposed on the document closer to a center of the document than to an end or edge of the document, for example a central portion of the document. In some embodiments, the hybrid document has a length greater than a width, and the inorganic light-emitting diode is disposed closer to the center than to the length-wise ends. In some embodiments, the hybrid document comprises a security feature such as a thread or ribbon, and the circuit or the component is disposed on or in the security structure (security feature), and the security structure is disposed on or in the document.

According to some embodiments of the present disclosure, the piezoelectric cantilever comprises a plurality of piezoelectric fingers. The fingers can be electrically connected in series or in parallel. The power component can comprise one or more masses and the one or more masses are disposed on ends of the plurality of piezoelectric fingers opposite opposing ends of the plurality of piezoelectric fingers that are adjacent to, on, or physically connected to the power support. The piezoelectric cantilever can extend from a side of the power support or an end of the piezoelectric cantilever can be disposed on the power support. Each component can comprise a plurality of power components; the plurality of power components can be electrically connected in series or in parallel.

According to embodiments of the present disclosure, a method of operating a hybrid document comprises providing a document, wherein the document is flexible and has a first end opposing a second end, grasping the document at the first end and at the second end, wherein the first end is separated from the second end and the document is at least partially flat, moving the first end and the second end closer together so that the document is at least partially folded or at least less flat, and moving the first end and the second end apart so that the document is at least partially flat and less folded, thereby moving the central portion in a vertical direction, making the piezoelectric cantilever move and generating electrical power, causing the inorganic light-emitting diode to emit light. In some embodiments, grasping comprises grasping with one or more fingers of one or more hands. In some embodiments, light is emitted with no perceptible delay between moving the first end and the second end apart and light emission (e.g., by a human).

According to some embodiments, a method of making a hybrid document comprises providing a component substrate on a component source wafer, patterning a first electrode, piezoelectric material, and a second electrode on or over the component substrate, patterning a power support in contact with the piezoelectric material on or over the component substrate, releasing the first electrode, piezoelectric material, and second electrode from the component substrate to form a released piezoelectric cantilever comprising the first electrode, the piezoelectric material, and the second electrode extending from the power support and a cavity, wherein the released piezoelectric cantilever is disposed over or in the cavity. In some embodiments, methods comprise capping the released piezoelectric cantilever to enclose the cavity. In some embodiments, methods comprise disposing the component substrate having the released piezoelectric cantilever and power support disposed thereon on a document after capping the released piezoelectric cantilever.

According to some embodiments, methods of the present disclosure comprise disposing a component comprising a component substrate having the released piezoelectric cantilever and the power support disposed thereon. Some embodiments comprise disposing a controller and one or more light-emitting diodes on the component substrate and electrically connecting the controller, one or more light-emitting diodes (e.g., iLEDs), and the released piezoelectric cantilever on the component substrate. According to some embodiments, methods of the present disclosure comprise patterning one or more capacitors on or over the component substrate using one or more same materials as the first electrode, the piezoelectric material, and the second electrode and in a common patterning step with the first electrode, piezoelectric material, and second electrode.

According to some embodiments, methods of the present disclosure comprise capping the piezoelectric cantilever with a cap before disposing the component substrate on a document (e.g., by removing the removed component substrate from the component source wafer).

According to some embodiments, methods of the present disclosure comprise disposing the removed component substrate on an intermediate substrate and disposing the intermediate substrate on the document. Some embodiments comprise disposing and electrically connecting a controller and one or more inorganic light-emitting diodes on the intermediate substrate. Some embodiments comprise capping the piezoelectric cantilever after disposing the removed component substrate on the intermediate substrate.

According to embodiments of the present disclosure, methods comprise providing the component substrate on a component source wafer, releasing the component substrate from the component source wafer after the cavity is enclosed, and disposing the component substrate having the released piezoelectric cantilever and the power support disposed thereon on a document.

According to some embodiments, the piezoelectric material extends from a side of the power support or an end of the piezoelectric material is disposed on the power support.

Some methods of the present disclosure comprise encapsulating the enclosed cavity with an encapsulation layer.

According to embodiments of the present disclosure, a hybrid document comprises a document and a component disposed in or on the document. The component can comprise a power component comprising a power support and a piezoelectric cantilever extending from the power support. The piezoelectric cantilever comprises a layer of piezoelectric material, a first electrode on a first side of the piezoelectric material and a second electrode on a second side of the piezoelectric material opposite the first side. The component can also comprise a controller disposed in or on the document and electrically connected to the power component and a light-controlling element disposed in or on the document and electrically connected to the power component, the controller, or both. The power component, the controller, and the light-controlling element can be comprised in a circuit that causes light to be directed away from the light-controlling element in response to power received from the power component. The circuit can cause light to be emitted from the light-controlling element in response to power received from the power component. The light-controlling element can be an inorganic light-emitting diode, organic light-emitting diode, controllable reflective element, or controllable electrophoretic element. The component can comprise a component substrate on or in which power component is formed. The controller and light-controlling element can be disposed on the component substrate. In some embodiments, the power component is disposed on an intermediate substrate and the controller and light-controlling element can be disposed on the intermediate substrate. In some embodiments, a plurality of power components are disposed on the intermediate substrate.

According to some embodiments of the present disclosure, a hybrid document comprises a document and a component disposed on or in the document. The component can comprise a piezoelectric cantilever and a light-controlling element. The light-controlling element can be operable to cause light to be directed away in response to power received from the piezoelectric cantilever. The light-controlling element can be an inorganic light-emitting diode and the light-emitting diode can emit light in response to power received from the piezoelectric cantilever. The piezoelectric cantilever can be disposed on or in a cavity and the cavity can be enclosed. The component can comprise a component substrate disposed on or in the document, the piezoelectric cantilever and the light-controlling element can be disposed on the component substrate, and the component substrate can comprise a cavity. The piezoelectric cantilever can be disposed over or in the cavity. The component can be disposed on or in a security structure and the security structure can be a ribbon or thread.

According to some embodiments of the present disclosure, a method of making a hybrid document comprises providing a component substrate, patterning a first electrode, piezoelectric material, and a second electrode on the component substrate, patterning a power support in contact with the piezoelectric material on or over the component substrate, releasing the power support and the first electrode, the piezoelectric material, and the second electrode from the component substrate to form a piezoelectric cantilever comprising the first electrode, the piezoelectric material, and the second electrode extending from the power support, and printing the power support and the piezoelectric cantilever together from the component substrate to an intermediate substrate. Some methods of the present disclosure comprise printing the power support and the piezoelectric cantilever to the intermediate substrate such that the piezoelectric cantilever is disposed over or in a cavity disposed in the intermediate substrate. Some methods of the present disclosure comprise disposing the intermediate substrate on a document. Some methods of the present disclosure comprise thinning the intermediate substrate prior to disposing the intermediate substrate on the document. Some methods of the present disclosure comprise printing the intermediate substrate having the power support and the piezoelectric cantilever disposed thereon to a document. Some methods of the present disclosure comprise capping the piezoelectric cantilever prior to the printing. Some methods of the present disclosure comprise disposing an encapsulation layer around the capped piezoelectric cantilever and the power support, forming a component tether with the encapsulation layer, the component tether connected to a component anchor; and printing together the encapsulated capped piezoelectric cantilever and power support to the intermediate substrate, thereby fracturing or separating the component tether. Some methods of the present disclosure comprise disposing a controller and one or more light-emitting diodes and electrically connecting the controller and the one or more light-emitting diodes to the piezoelectric cantilever either (i) on the component substrate before the printing and before the disposing of the encapsulation layer or (ii) on the intermediate substrate after the printing of the encapsulated capped piezoelectric cantilever and power support. Some methods of the present disclosure comprise patterning one or more capacitors on the component substrate before disposing the encapsulation layer, such that the encapsulation layer physically connects the one or more capacitors with the capped piezoelectric cantilever after disposing the encapsulation layer, and printing together the encapsulated capped piezoelectric cantilever and power support comprises printing together the one or more capacitors to the intermediate substrate. Some methods of the present disclosure comprise patterning one or more capacitors comprises using one or more same materials and in a common patterning step with patterning of the first electrode, the piezoelectric material, and the second electrode.

The present disclosure provides an anonymous, government-issued currency with anti-counterfeiting light emitters whose value or validity can be visibly ascertained without requiring specialized equipment and modified electronically.

Features and advantages of the present disclosure will become more apparent from the detailed description set forth below when taken in conjunction with the drawings, in which like reference characters identify corresponding elements throughout. In the drawings, like reference numbers generally indicate identical, functionally similar, and/or structurally similar elements. The figures are not drawn to scale since the variation in size of various elements in the Figures is too great to permit depiction to scale.

DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS

Referring toFIG. 1, in some embodiments of the present disclosure a hybrid currency banknote10includes a banknote20having visible markings22. The banknote20can be a government-issued banknote20indicated by the visible markings22and can comprise a flexible substrate that includes paper, plastic, or impregnated paper. One or more light-controlling elements30are embedded in or on the banknote20and can be printed on the flexible substrate. A controller40is embedded in or on the banknote20and electrically connected to the one or more light-controlling elements30for controlling the one or more light-controlling elements30. A power input connection50is electrically connected to the controller40, one or more light-controlling elements30, or both. In a further embodiment, a power source60is electrically connected to the power input connection50, for example directly to the power input connection50(not shown) or through a power convertor64(as shown). The power source60and the controller40can be a common element or a common circuit and the controller40can be a power conditioning circuit or can include analog or digital control circuitry. The controller40, the light-controlling elements30and the power input connection50can be electrically connected, for example with wires52. Multiple controllers40can be used to provide redundancy, reduce failures, and increase lifetime. The multiple controllers40can be connected in parallel with common input, output, power, and ground connections. In other embodiments, the controller40can include multiple circuits in multiple integrated circuits and include discrete components, such as capacitors and resistors that can provide additional control support, for example as timing or trimming devices to support light-controlling element30flash rates, filter devices such as acoustic wave devices (either bulk or surface).

The power source60can be a piezoelectric power source or a photovoltaic power source and the power convertor64can convert the power provided by the power source60to a form that is used by the controller40, the light-controlling elements30, or both. The power convertor64can include power storage, for example using capacitors such as thin-film capacitors with a high-K dielectric to provide power over a time period. The capacitors can be distributed, for example located among the power components62. Output diodes can be used to isolate the power source60or light-controlling elements30. In one arrangement, the power source60is indicated by the visible markings22, the power source60forms a part of the visible markings22, or the power source60is obscured by the visible markings22. Multiple power sources60and multiple power convertors64can be used to provide redundancy.

In some embodiments, the power source60comprises a plurality of electrically connected but physically separated individual power components62. The power components62can be arranged in a 2-d array (as shown) or a 1-d array (not shown) and operated by squeezing, waving, or sliding an object across the power components62. The power components62can be a group of elements that are operated at the same time with a single action, for example pressure applied to all of the power components62simultaneously. The power components62can be electrically arranged in series to achieve a desired voltage or in parallel to achieve a desired current or some combination of series and parallel to achieve the desired power characteristics.

The light-controlling elements light-controlling elements30can be inorganic light-emitting diodes30such as micro-light-emitting diodes suitable for micro-transfer printing, for example made on a semiconductor wafer adapted to the manufacture of inorganic light-emitting diodes30. In general, the light-controlling elements30can be light-emitting elements, light-reflecting elements, inorganic light-emitting diodes, organic light-emitting diodes, micro-electromechanical reflective elements, reflective electrophoretic elements, or reflective electrochromic display elements. For clarity of exposition, the light-controlling elements30of the present disclosure are referred to below as inorganic light-emitting diodes (iLEDs)30. However, in various embodiments the present disclosure contemplates the use of a corresponding variety of light-controlling elements30. In another embodiment, the light-controlling elements30are also energy harvesting elements (for example silicon photodiodes) and provide power as part of the power source60.

The controller40can also be an integrated circuit, for example a small chiplet, suitable for micro-transfer printing. The controller40can include digital circuits or logic (for example CMOS circuits) and power circuits (for example for driving an iLED30). The controller40can include information storage circuits, a state machine, or a stored program machine to implement the desired functionality of the hybrid currency banknote10. The controller40can read or write information such as currency values, process information, respond to input and provide output. The power input connection50can be directly connected to the controller40(as shown) or to the iLEDs30, or both. Alternatively, the power input connection50can indirectly connect to the controller40or the iLEDs30, or both through the power convertor64(not shown). The power input connection50can be an electrical conductor, for example small wires52, and can include power connection pads that, when electrically connected to a power source, (such as a 3.3-volt, 5-volt, or 12-volt power source), provides power to the controller40and iLEDs30to enable them to function. The power source can be external (not shown) or can be provided by the internal power source60.

It can be desirable to fold or spindle the hybrid currency banknote10of the present disclosure. To facilitate such a manipulation, in some embodiments of the present disclosure, the power source60comprises a plurality of electrically connected smaller individual power components62. A single large power source60can be too rigid to readily fold or curve, whereas an arrangement of individual smaller physically separate power components62can allow folding between the smaller power components62, even if the smaller power components62themselves are relatively rigid.

In a further embodiment, the iLEDs30and controller40are too small to be readily visible with the unaided human eye. Furthermore, the iLEDs30and controller40can be located in areas of the banknote20that include visible markings22to further obscure the presence of the iLEDs30and controller40, as well as any wires52. Similarly, the power source60or an arrangement of individual smaller power components62can be obscured by the visible markings22. In one embodiment, any of the iLEDs30, controller40, wires52, power source60, power components62, or power convertor64are marked with visible markings22. For example, ink can be printed over the iLEDs30, controller40, wires52, power source60, power components62, or power convertor64to obscure them or otherwise make them a part of the visible markings22on the banknote20. Since the the iLEDs30, controller40, wires52, power source60, power components62, or power convertor64can each be very small, for example having a size in the micron range, they can be effectively invisible to the unaided human eye. For example, the one or more inorganic micro light-emitting diodes30or the controller40of the hybrid currency banknote10can have a width from 2 to 5 μm, 5 to 10 μm, 10 to 20 μm, or 20 to 50 μm, a length from 2 to 5 μm, 5 to 10 μm, 10 to 20 μm, or 20 to 50 μm, or a height from 2 to 5 μm, 4 to 10 μm, 10 to 20 μm, or 20 to 50 μm.

In one embodiment of the present disclosure, the iLEDs30and controller40are directly printed onto a banknote20, for example before or after the banknote20is printed with ink. In this embodiment, wires52can be woven into the banknote20in predetermined locations at which the iLEDs30and controller40are printed before or after the iLEDs30and controller40are printed. Referring toFIG. 2in another embodiment, the banknote20includes a metalized or metallic ribbon70or thread, for example Mylar, with a pattern of electrical conductors or wires52. The iLEDs30and controller40are printed, for example micro-transfer printed, onto the ribbon70before or after the electrical conductors such as wires52are formed, patterned, or impressed into the ribbon70to make an electrical circuit. In some such embodiments, the iLEDs30and controller40can include at least a portion of an LED tether31(seeFIG. 20, for example), resulting from the fracturing of an LED tether31on an iLED source wafer from which the iLEDs30and controller40originate and that connects the iLEDs30and controller40to an anchor on the source wafer in the micro-transfer printing process. The ribbon70or thread is then incorporated into the banknote20to make an embodiment of a hybrid currency banknote10of the present disclosure. The power source60(and any power components62), power convertor64, or power input connection50can likewise be formed in the ribbon70. Alternatively, some components can be on the ribbon70and others not on the ribbon70, in particular the power source60.

Referring toFIG. 3, in some embodiments, the one or more inorganic LEDs30are disposed in a location corresponding to a portion of the visible markings22to highlight or otherwise indicate the portion of the visible markings22. For example, the one or more inorganic LEDs30can underline or surround a graphic element of the visible markings22. As shown inFIG. 3, the one or more inorganic LEDs30outline the numeral5. Thus, the one or more inorganic LEDs30can be disposed to form a graphic indicator such as any of one or more of a number, a letter, and a pictogram. The graphic indicator can have semantic content, for example indicating a value, a date, or a person.

Referring next toFIG. 4, one or more light pipes32are located in association with the one or more inorganic light-emitting diodes30to transmit light emitted by the inorganic light-emitting diodes30through the light pipes32and emit the transmitted light from the opposite end of the light pipe32. In some embodiments, the light pipes32include portions that leak light at desired locations, for example by purposefully forming nicks, scratches, or other forms of light diffusers34in the light pipes32to allow light to leak from the light pipe32. Thus, the arrangement of the light pipes32can also correspond to a portion of the visible markings22to indicate (e.g., highlight) the portion of the visible markings22, form a graphic indicator, or form any one or all of a number, a letter, and a pictogram to indicate a value, a date, or a person.

The controller40can control the one or more inorganic light-emitting diodes30to flash or sequentially flash individual iLEDs30, forming spatial, temporal, or temporal-spatial light patterns. Referring toFIG. 5, in some embodiments, the inorganic light-emitting diodes30can emit different colors of light. For example, a red light-emitting diode82can emit red light, a green light-emitting diode84can emit green light, and a blue light-emitting diode86can emit blue light. The different inorganic light-emitting diodes30can be arranged spatially to form a display80, a two-dimensional array, or a graphic element.

In another embodiment of the present disclosure and referring toFIG. 6, the hybrid currency banknote10includes visible markings22that do not include a value. Such a hybrid currency banknote10can be a non-denominational banknote that either has an assigned value or a variable value stored in a memory44in the controller40, as shown inFIG. 7. Referring toFIG. 7, an assigned value can be provided by providing a circuit42and memory44in the controller40or providing circuits42, such as the memory44, connected to the controller40. The memory44can be a read-only memory that encodes a desired assigned value. The assigned value can be a currency value or can include an electronic serial number, or both. The assigned value can be discovered by providing power to the power input connection50. The power energizes the controller40which, in turn, controls the iLEDs30to display or otherwise indicate the assigned value. The memory44can be protected from overwriting, damage, or alternative discovery by protective layers such as a protective shield46formed over the memory44to discourage exposure by light and protect the memory44from heat. The shield46can be a light shield, a light reflector, a light absorber, or a heat conductor.

In the case in which the assigned value is variable, the memory44can be a write-once memory that stores multiple values in memory locations that are ordered in a sequential order, for example by memory address. The write-once memory can, for example, employ fuses that are electrically destroyed and cannot be rewritten. Alternatively, the memory44can be a non-volatile read-write memory. In this case, the value stored by the hybrid currency banknote10can change over time. The current value can be discovered by providing power to the power input connection50. The power energizes the controller40which, in turn, controls the iLEDs30to display or otherwise indicate the current value. The current value can be modified by, for example, a teller machine. Referring toFIGS. 8 and 9, in some embodiments of the present disclosure, the hybrid currency banknote10is adapted to a hybrid currency teller machine90that writes a value into the memory44in a memory storage location having an address sequentially after the address of a previous written value. As shown inFIG. 8, the power input connection50includes or is connected to power connection pads66that can be contacted by an external power source to provide power to the controller40and iLEDs30through wires52. Referring toFIG. 9, a hybrid currency teller machine90includes a slot91into which a hybrid currency banknote10can be inserted. Once inserted into the hybrid currency teller machine90, the hybrid currency banknote10is read by a reader92that can access the controller40or memory44, for example by contacting electrical conductors to the power connection pads66. (Only two power connection pads66are illustrated, but one or more power connection pads66can be included in various embodiments of the present disclosure). Once the current value of the hybrid currency banknote10is read, it can be displayed, for example on an optional teller machine display96. If a change in the current value of the hybrid currency banknote10is desired, an input value can be input by a user with an input device94. A teller machine controller98can then calculate or otherwise determine a new stored value responsive to the input value and store the new value in the hybrid currency banknote10, for example by communicating the new stored value to the controller40which then writes the new stored value in the memory44with a writer93. In some embodiments, the controller40only writes new stored values in the memory44that are smaller than the current value. In another embodiment, the controller40can write new stored values in the memory44that are larger than the current value, or that are larger than the current value but are limited to a maximum value. The change in current value of the hybrid currency banknote10can represent or be the result of a financial transaction, for example a purchase or a financial exchange with or facilitated by a financial institution such as a bank. Read-only memories, write-once memories, and read/write memories together with controllers and read/write circuitry (e.g., reader92and writer93) can be formed in integrated circuits and electrical circuits. Devices for currency handling, optical inspection, making physical electronic contacts, displays, input devices (such as keyboards or touch screens) can be made using electromechanical, electronic, and optical technologies.

Referring toFIG. 10, a hybrid currency banknote10of the present disclosure can be made by providing a banknote20with markings in step100, for example by printing on a high-quality paper with ink using intaglio printing. A ribbon70is provided in step110, an inorganic LED wafer having micro-transfer printable iLEDs30is provided in step120, and a controller source wafer having micro-transfer printable controllers40is provided in step130. The iLEDs30are micro-transfer printed from the inorganic LED wafer onto the ribbon70using a stamp to fracture LED tethers31connecting the iLEDs30to the inorganic LED wafer leaving at least a portion of an LED tether31on the iLEDs30in step140. The controllers40are micro-transfer printed from the controller source wafer onto the ribbon70using a stamp to fracture controller tethers65connecting the controllers40to the controller source wafer leaving at least a portion of a controller tether65on the controllers40in step150. Optionally, the power source60is similarly micro-transfer printed to the ribbon70in step160. Power connection pads66, wires52and any other necessary electrical conductors are formed in step170to make an electronic circuit having electrical conductors. The electrical conductors can be provided before or after the iLEDs30and controllers40are micro-transfer printed. The ribbon70can be further processed, for example to provide environmental robustness by coating with protective layers. The ribbon70is then integrated into the banknote20in step180to make the hybrid currency banknote10of the present disclosure. The hybrid currency banknote10can be further processed, for example by over coating or printing to provide environmental robustness, decoration, or to obscure the micro-transfer printed elements.

Referring toFIG. 11, the hybrid currency banknote10of the present disclosure can be used by first receiving the hybrid currency banknote10in step200, providing power to the hybrid currency banknote10in step210, and viewing light emitted by the hybrid currency banknote10in step220. Power can be provided by connecting the hybrid currency banknote10to an external power source (e.g., using the power connection pads66), squeezing a piezoelectric power source60, or exposing a photovoltaic power source60to light.

Referring toFIG. 12, an assigned or current value can be programmed into the controller40or an associated memory44(also micro-transfer printed if it is a separate integrated circuit or chiplet) either before or after the controller40or memory44is micro-transfer printed. Alternatively, an external device such as a hybrid currency teller machine90can communicate with the controller to write an assigned or current value to the hybrid currency banknote10. For example, the hybrid currency banknote10can be received in step200, inserted into the hybrid currency teller machine90in step250, the current value read by the reader92in step260, an input value input by the input device94in step270, a new stored value responsive to the input value computed by the teller machine controller98and stored by the writer93in step280and the hybrid currency banknote10returned in step290. Optionally, the hybrid currency teller machine90can also communicate with a central or remote database (step272) to establish the legitimacy of the hybrid currency banknote10, track its use or location, or approve a transaction and record or approve the transaction (step274). The communication can include an electronic serial number.

U.S. patent application Ser. No. 14/743,981, filed Jun. 18, 2015, entitled Micro Assembled Micro LED Displays and Lighting Elements, incorporated herein by reference describes micro-transfer printing structures and processes useful with the present disclosure. For a discussion of micro-transfer printing techniques see also U.S. Pat. Nos. 8,722,458, 7,622,367 and 8,506,867, each of which is hereby incorporated by reference in its entirety. Micro-transfer printing using compound micro assembly structures and methods can also be used with the present disclosure, for example, as described in U.S. patent application Ser. No. 14/822,868, filed Aug. 10, 2015, entitled Compound Micro Assembly Strategies and Devices, which is hereby incorporated by reference in its entirety.

A simplified schematic of some embodiments of the present disclosure is illustrated inFIGS. 13 and 14. As shown in these Figures, a power source60includes two parallel groups of four series-connected power components62electrically connected to the power input connection50and the power convertor64and controller40. The power convertor64and controller40can be a single component, as shown, or include multiple different components such as separate integrated circuits. Control current from the power convertor64and controller40drives the iLEDs30of the display80to emit light88. A capacitive touch sensor68is also included (FIG. 13). InFIG. 13, the power source60is a photovoltaic power source. InFIG. 14, the power source60is a piezoelectric power source.FIG. 15illustrates an example power convertor64and controller40having a four-diode bridge rectifier and storage capacitor CR (for example, see capacitor67inFIG. 22) providing power from a piezoelectric power source60to a current limiter that, in turn, provides current to the iLEDs30to emit light88. (The controller40can be powered by the power source60to control the iLEDs30but is not illustrated inFIG. 15. As noted above, the controller40and power source60can be a common component or circuit or can be separate or individual components or circuits.)

Referring toFIG. 16, a power component62can include a dielectric layer such as a silicon nitride layer with a first metal layer providing a first connection post69or spike. A piezoelectric material layer is in electrical contact with the first metal layer and, on a side of the piezoelectric material layer opposite the first metal layer, a second metal layer is in electrical contact with a second metal layer and forms a second connection post69or spike. The power component62ofFIG. 16can be micro-transfer printed onto two conductors (e.g., wires52) so that the first and second connection posts69are in contact with the conductors. The first and second connection posts69can pierce or otherwise deform and adhere to the conductors after micro-transfer printing.

FIG. 17illustrates the process of making a banknote20according to some embodiments of the present disclosure. A printed banknote is provided together with a ribbon70having an array of micro-transfer printed iLEDs30electrically connected to a controller, a power convertor64, and a power source60. The ribbon70is laminated or otherwise integrated into the banknote20to make a hybrid currency banknote10.

As shown inFIG. 18, a hybrid currency banknote10of the present disclosure having a photovoltaic power source60can be exposed to ambient illumination to provide power to iLEDs30in a display80, causing the iLEDs30to emit light88. It has been calculated that conventional ambient office light provides sufficient illumination (e.g., 500 lux) to operate a photovoltaic embodiment of the present disclosure, including digital control for iLEDs30sequencing, for example flashing. Photovoltaic cells (e.g., power components62) can be GaAs having lateral dimensions of 50μ by 50μ and providing 66 μW in an array of 50,000 power components62and requiring approximately 1.27 cm2. The array of power components62can occupy a larger area with a lower fill factor to provide apparent transparency and improved flexibility to the power source60. A 20×20 array of 400 iLEDs30(for example, green-light-emitting iLEDs30) can provide a readable display80in these conditions over a viewing angle of 140 degrees similar to displays found in body-worn electronic devices (e.g., watches, fitness trackers) and can consume 66 μW.

As shown inFIG. 19, a hybrid currency banknote10of the present disclosure having a piezoelectric power source60can be pressed or squeezed, for example, by a finger, to provide power to iLEDs30in a display80, causing the iLEDs30to emit light88. Power is provided both when pressing and releasing (hence the use of a bridge rectifier inFIG. 15). It has been demonstrated that a fingertip having a one square cm area can provide a force of 35 N. Even with a smaller force of 10 N, a piezoelectric power source60with a total area of 0.06 cm2provides sufficient power to operate a piezoelectric embodiment of the present disclosure, including digital control for iLEDs30sequencing, for example flashing. The array of power components62can occupy a larger area (e.g., 0.5 cm2) with a lower fill factor to provide apparent transparency and improved flexibility to the power source60.

According to another embodiment of the present disclosure, a hybrid currency banknote10can have one or more energy output devices embedded in or on hybrid currency banknote10. The one or more energy output devices can be one or more of one or more light-emitting elements, a sound-emitting element, and a vibration element. The sound-emitting element can be a piezoelectric speaker and the vibration device can be a piezoelectric device. The elements can be controlled, powered, hidden, constructed, or otherwise provided in ways similar to those of the light-emitting elements30discussed at greater length above. Such alternative energy output modalities can be useful for persons with impaired vision.

In a further embodiment of the present disclosure, a hybrid document10(e.g., a hybrid currency banknote10) comprises a document20having visible markings22and one or more light-controlling elements30(e.g., inorganic light-emitting diodes30) embedded in or on document20(FIG. 1). A controller40is embedded in or on document20and is electrically connected to the one or more light-controlling elements30for controlling the one or more light-controlling elements30. The electrical connection can be a wire connection or other methods, such as capacitive alternating current coupling, can be used to control light-controlling element30. The one or more light-controlling elements30can emit or control light of different colors and can be located in a variety of locations in or on documents20, for example in an array and controlled by controller40to display fixed or programmable patterns. A power input connection50can be electrically connected to any one or all of controller40, power convertor64, circuit42, memory44, or the one or more light-controlling elements30. Controller40can control light-controlling elements30(e.g., iLEDs30).

In various embodiments, document20is a banknote20(as shown inFIG. 1), a bond, a stock certificate, a commercial certificate, a printed value-bearing document, an identification document, or a government-issued document, for example a passport or license. A bond can be a commercial, municipal, or corporate bond, a government-issued bond, or bearer bond, or other debt security.

As with hybrid currency banknote10described above, light-controlling elements30of hybrid documents10can be light-emitting elements, light-reflecting elements, inorganic light-emitting diodes30, organic light-emitting diodes, micro-electromechanical reflective elements, reflective electrophoretic elements, or reflective electrochromic display elements. In some embodiments of the present disclosure, hybrid document10vibrates or emits acoustic signals, such as audible sounds, tones, or sequences of sound, for example in a melody using, for example, polymer piezo films or electrostatic speakers. A hybrid document10can include one or more output modes, for example a light-controlling mode or an acoustic mode, or both a light-controlling mode and an acoustic mode.

In some configurations of the present disclosure, a power source60can be connected to power input connection50of hybrid document10(as shown inFIG. 1). Power source60can be a piezoelectric power source or a photovoltaic power source, can incorporate MEMs devices, and can be integrated into hybrid document10. Piezoelectric power source60can provide power in response to pressure, as described above, or, in other embodiments, in response to pushing, pulling, stretching, flapping, or waving hybrid document10or providing other rapid movement, for example along the longest dimension of hybrid document10. Power can be provided using IR, UV, visible light, or other electromagnetic radiation to a photovoltaic unit via optical coupling. The electromagnetic radiation can be pulsed or encoded to provide information or signals. The electromagnetic energy source could be ambient light (for example the sun), broadband or narrowband artificial light (for example light bulbs or LEDs of various types), or narrowband high-energy sources, such as LEDs or lasers. In another embodiment, power source60is external to hybrid document10and power is transmitted to controller40or light-controlling elements30, for example through electrical conductors (e.g., wires52) in hybrid documents10. In other configurations, inductive or magnetic coupling is employed to transmit power.

Inorganic light-emitting diodes (iLEDs)30can be horizontal diodes with LED tethers31, as shown inFIG. 20. Similarly, controller40or power convertor64can be comprise or be attached to a controller tether65or convertor tether65, as shown inFIG. 21. A fractured or separated tether on or attached to a device indicates that the device was transfer printed (e.g., micro-transfer printed) from a source device wafer. For example, inorganic light-emitting diodes30can be micro-transfer printed from an inorganic light-emitting diode source wafer, controller40can be micro-transfer printed from a controller source wafer, and power convertor64(if distinct from controller40) can be micro-transfer printed from a power convertor source wafer.

According to some embodiments of the present disclosure, a hybrid currency banknote10comprises a flexible banknote20(document20) having visible markings22(e.g., as shown inFIG. 1). A component36(shown inFIG. 22) is embedded in or on relatively flexible banknote20or in or on a ribbon70or thread incorporated into flexible banknote20. Component36comprises a component substrate38and one or more relatively rigid inorganic light-emitting diodes30(rigid compared to flexible banknote20) disposed on component substrate38. Component substrate38can also be relatively rigid compared to flexible banknote20. A controller40is disposed on component substrate38and electrically connected to one or more inorganic light-emitting diodes30for controlling the one or more inorganic light-emitting diodes30. Controller40can also be a power convertor64or power convertor64can be a controller40. In some embodiments, controller40and power convertor64are a same device or a common device. A power input connection50is electrically connected to controller40, power convertor64, the one or more inorganic light-emitting diodes30, or any combination of these. The one or more inorganic light-emitting diodes30each can comprise a fractured or separated LED tether31, controller40can comprise a fractured or separated controller tether65(convertor tether65), component substrate38can comprise a fractured or separated component tether37, or any one or combination of these. Component36can be constructed on a component source wafer and then micro-transfer printed from the component source wafer, thereby fracturing or separating component tether37.

According to embodiments of the present disclosure and as illustrated inFIG. 22, a power source60is connected to power input connection50. Power source60can be disposed on component substrate38, as shown inFIGS. 22 and 23, for example by constructing power source60on component substrate38, e.g., with potassium sodium niobate (KNN), or by micro-transfer printing power source60from a power source substrate to component substrate38. In some embodiments, power source60is disposed on flexible banknote20external to component substrate38(as shown inFIG. 24) and electrically connected to power input connections50and component36, as shown in the electrical diagram ofFIG. 25, for example by wires52embedded in flexible banknote20. Power source60can be photovoltaic power source, a piezoelectric power source activated by pressure, or a piezoelectric power source activated by movement, for example flapping flexible banknote20or bringing ends of flexible banknote20near to each other (e.g., as in folding flexible banknote20in half) and then separating the ends of flexible banknote20from each other to the extent possible, e.g., flattening flexible banknote20, thereby mechanically moving power source60. In some embodiments, power source60harvests electromagnetic energy and comprises an antenna or a photodiode. Power source60or component36can be indicated by visible markings22, power source60or component36can form a part of visible markings22, or power source60or component36can be obscured by visible markings22.FIG. 26illustrates embodiments in which power source60is provided on component substrate38and emits light88when power is provided, for example by exposure to electromagnetic radiation or mechanical movement.FIG. 27illustrates embodiments in which power source60is provided on component substrate38and emits light88when power is provided, for example by exposure to electromagnetic radiation or mechanical movement, for example as disclosed inFIGS. 22 and 23.FIG. 28illustrates embodiments in which power source60is provided external to component substrate38and emits light when power is provided, for example by mechanical pressure on flexible banknote20, for example as disclosed inFIG. 24.

As shown in the perspective ofFIG. 22, power source60can comprise a plurality of electrically connected individual power components62. Power components62can be electrically connected in series (as shown), in parallel, or in a combination of series and parallel. Component36can comprise a power convertor64disposed on component substrate38and connected to power input connection50. Power convertor64can be electrically connected to controller40or one or more inorganic light-emitting diodes30. In some embodiments, power convertor64and controller40are a common device or circuit. Power convertor64converts the power provided from power input connection50from power source60to a form that is used by controller40(if controller40is distinct from power convertor64) or inorganic light-emitting diodes30, or both.

In some embodiments of the present disclosure and as shown inFIG. 22, power convertor64comprises a unitary capacitor67. In some embodiments, power convertor64comprises a disaggregated capacitor67comprising multiple capacitors67electrically connected in parallel, as shown inFIGS. 23-25with32individual capacitors67each 200 by 200 microns square. In some embodiments, power convertor64comprises a diode, as shown inFIG. 22. Thus, in the illustrated embodiments, power convertor64or controller40, can include multiple elements (e.g., a capacitor, multiple capacitors, and a diode) that can be constructed and assembled separately of different materials. For example, capacitor67can be constructed on component substrate38(e.g., constructed of KNN) and the diode can be micro-transfer printed onto component substrate38from a diode source wafer. In some embodiments, power convertor64comprises any one or combination of these. A disaggregated structure for power convertor64or power source60can provide a more mechanically robust structure that can be at least somewhat flexed without cracking. In embodiments illustrated inFIG. 22, power convertor64(comprising a capacitor67and diode) rectifies and stores charge generated by power source60until the charge exceeds the amount needed to pass through three inorganic light-emitting diodes30, causing the inorganic light-emitting diodes30to emit light. The emitted light can flash or flash sequentially. In some embodiments, power source60and at least some portions of power convertor64are constructed of common materials in common steps, for example using KNN using photolithographic methods and can be formed on component substrate38using photolithographic methods and materials.

According to embodiments of the present disclosure, flexible banknote20is a government-issued banknote20indicated by visible markings22. Flexible banknote20can include or comprise a flexible substrate that includes paper, plastic, or impregnated paper, and component substrate38can be transfer printed or otherwise disposed on or in the flexible substrate. In some embodiments, flexible banknote20comprises a ribbon70or thread woven into flexible banknote20and component36is disposed on the ribbon70or thread. The ribbon70or thread or portions of the ribbon70or thread can be at least partially electrically conductive or include conductive wires52, for example electrically connecting power source60to component36through power input connections50. Component36can be disposed in a location corresponding to a portion of visible markings22to highlight or otherwise indicate the portion of visible markings22. Some embodiments of the present disclosure comprise a plurality of components36disposed on flexible banknote20in a random arrangement or in a regular array. Components36can form a one-dimensional (e.g., a line), a two-dimensional array (e.g., a display), or form a symbol.

As illustrated inFIGS. 28 and 29, a method of making a hybrid currency banknote10comprises providing a flexible banknote20having visible markings22in step100, providing a ribbon70in step110, and providing a component source wafer in step300comprising relatively rigid component substrates38(relative to flexible banknote20). An inorganic light-emitting diode (iLED) source wafer is provided in step120. The light-emitting diode source wafer has a plurality of relatively rigid micro-transfer printable inorganic light-emitting diodes30connected by LED tethers31to the light-emitting diode source wafer. A controller source wafer having a plurality of controllers40(or power convertors64) connected by controller tethers65to the controller source wafer is provided in step130. Controllers40on controller source wafer can comprise power convertors64or a separate power convertor source wafer can be provided from which power convertors64can be transfer printed (generally included in step130inFIGS. 28 and 29).

In step310, iLEDs30are micro-transfer printed from the iLED source wafer and controllers40(or power convertors64) are micro-transfer printed from the controller source wafer with a stamp to component substrate38in step320thereby fracturing or separating each LED tether31that connected the one or more of the plurality of inorganic light-emitting diodes30to the light-emitting diode source wafer and each controller tether65that connected the at least one of the plurality of controllers40to the controller source wafer to provide a component36. In step330component36is embedded in or on flexible banknote20or in or on a ribbon70or thread. Controllers40(and power convertors64) are electrically connected to the one or more of the plurality of inorganic light-emitting diodes30and to a power input connection50in step160. In embodiments in which power source60is provided on flexible banknote20external to component substrate38and component36, the electrical connections (step170) can be made after power source60is disposed on the ribbon70(in step160,FIG. 28). InFIG. 29, power source60is disposed on or in component36(e.g., on component substrate38) and the electrical connections can be made, for example by photolithographic methods and materials, before disposing component36on the ribbon70(or flexible banknote20) in step330, for example by micro-transfer printing components36from the component source wafer onto the ribbon70(or flexible banknote20). Once components36are disposed in or on the ribbon70, the ribbon70can be integrated into flexible banknote20in step180.

Embodiments of the present disclosure, and as illustrated inFIGS. 19 and 27, provide power to hybrid currency banknote10by pressing or squeezing a power source60, for example by a finger, to provide power to iLEDs30, causing iLEDs30to emit light88. Light88is emitted remotely from power source60and remotely from the location of the pressing. Either electrical power or light can be transmitted from power source60(e.g., from the location of pressing) to the light emission location on hybrid currency banknote10by wires52or light pipes32(light guides32), respectively. In some embodiments, such as those illustrated inFIGS. 22 and 23, power source60and iLEDs30are disposed together on a relatively small common component substrate38and thus an object used to press or squeeze power source60(e.g., a finger) obscures light88emitted from iLEDs30. In some such embodiments, controller40(e.g., power convertor64and an electrically connected array of capacitors67) can accumulate electrical power and delay light88output from light-emitting diodes30until the pressing or squeezing object is removed and no longer obscures light88emitted from iLEDs30, allowing a user to view light88emitted by iLEDs30. Thus, in some embodiments, hybrid document10(e.g., hybrid currency banknote10) is constructed to emit light88immediately on activation (e.g., pressing) of power source60and, in some embodiments, hybrid document10(e.g., hybrid currency banknote10) is constructed to emit light88after a short period of delay after activation (e.g., pressing) of power source60(e.g., within two seconds, within one second, within one half second, or within one tenth second).

According to some embodiments of the present disclosure, power source60and light-emitting diodes30are provided together on a relatively small common component substrate38without obscuring light88output from iLEDs30when power source60is activated. For example, embodiments relying on photovoltaic or other electromagnetic sources or relying on electrical or magnetic fields can accumulate electrical power and cause iLEDs30to emit light without mechanical stimulation by an obscuring object. Embodiments relying on mechanical stimulation, such as pushing, pulling, stretching, flapping, or waving hybrid document10or providing other rapid movement, for example along the longest dimension of hybrid document10or in a direction perpendicular to a surface of hybrid document10, can also provide power without obscuring iLEDs30. Such embodiments can be made to immediately emit light88without delay, making operating hybrid document10more responsive and intuitive and thereby increasing user satisfaction.

According to some embodiments of the present disclosure and as illustrated inFIGS. 22 and 30-31B, a hybrid document10comprises a document20and a power component62disposed on or in document20. Power component62comprises a power support74and a piezoelectric cantilever72extending from power support74. Piezoelectric cantilever72comprises piezoelectric material71, a first electrode54on a first side of piezoelectric material71, and a second electrode56on a second side of piezoelectric material71opposite the first side. Piezoelectric cantilever72is affixed at one end to power support74and an opposite end of piezoelectric cantilever72projects over document20and is free to move, for example to mechanically oscillate in an oscillation direction78perpendicular to a document surface24of a document substrate of document20.

Piezoelectric material71can comprise (K, NA)NbO3(KNN) or lead zirconate titanate (PZT) or another piezoelectric material71, for example having a thickness from 0.5 microns to 2 microns, that can be used to generate electrical power in response to mechanical stimulation (e.g., physical motion). The electrical power is transmitted by first and second electrodes54,56and transmitted (e.g., by electrically connected wires52) to controller40or iLED(s)30, or both. First and second electrodes54,56can be a patterned metal, metal alloy, or can comprise layers of metal, for example 100 nm-500 nm of Ti/Au. Controller40can be an integrated circuit (e.g., a silicon CMOS integrated circuit). Controller40can be an integrated circuit or can be a simple circuit comprising one or more of a diode, rectifier, and bridge circuit, with or without capacitor(s)67. Controller40and capacitor(s)67can receive and control the generated electrical power from power component62and cause inorganic light-emitting diode(s)30to emit light.

Capacitor(s)67can comprise or be a same material as piezoelectric cantilever72, for example comprising first and second electrodes54,56on either side of piezoelectric material71provided in common layer(s) with piezoelectric cantilever72. For example, in some embodiments, piezoelectric material71that is used for piezoelectric cantilever72can be used for the dielectric in capacitor(s)67. Thus, manufacturing costs can be reduced by providing capacitor(s)67, portion(s) thereof, and piezoelectric cantilever72in common deposition and patterning steps (e.g., a common patterned photolithographic deposition). Additionally, in some embodiments, terminals for capacitor(s)67can be formed in common deposition and patterning steps with first and second electrodes54,56. In some embodiments, capacitor(s)67can use different materials from piezoelectric cantilever72, for example using a different dielectric material formed in a different patterned deposition step.

Capacitor(s)67can have an area of 50×50 to 200×200 microns squared. iLEDs30can be horizontal or vertical LEDs, such as inorganic light-emitting diodes30, and can have a size of 8×15 microns to 50×80 microns or larger. Power component62, controller40, iLED(s)30, and, optionally, capacitor(s)67, are at least a portion of (e.g., all of) a circuit42that emits light from iLED30in response to power received from (e.g., and generated by) power component62. Other components can be included in circuit42beyond power component62, controller40, light-emitting diode(s)30, and capacitor(s)67, for example if more complex control or power generation, management, or distribution is desired.

Document20can have a document substrate with a document surface24and circuit42can be disposed on document surface24, iLEDs30can be disposed on document surface24, power component62can be disposed on document surface24, controller40can be disposed on document surface24, or capacitor(s)67can be disposed on document surface24. Document20can be flexible and can be a banknote, for example made from a paper, such as a cotton fiber paper, or polymer material or a combination thereof. Piezoelectric cantilever72can extend over document20(e.g., over document surface24) or can extend within document20in a cantilever plane76that is non-orthogonal to document surface24of document20and piezoelectric cantilever72can be operable to oscillate in a direction non-parallel to cantilever plane76. In some embodiments, cantilever plane76can be substantially parallel to document surface24of document20and piezoelectric cantilever72is operable to oscillate in a direction substantially orthogonal to cantilever plane76. By substantially parallel or substantially orthogonal (e.g., perpendicular) is meant as preferably intended or desired (e.g., within 20%, within 10%, within 5%, within 2%, within 1%, or within the capabilities of a manufacturing process). For example, cantilever plane76can be intended or desired to be parallel to document surface24and can be intended or desired to oscillate in a direction perpendicular to document surface24even if some slight deviation exists in the final manufactured product.

According to some embodiments, hybrid document10comprises a component36comprising a component substrate38disposed on document20and power component62, controller40, and inorganic light-emitting diode(s)30are disposed on or in component substrate38of component36. For example, component substrate38can be a semiconductor (such as silicon) substrate, a polymeric substrate, or an inorganic dielectric substrate. Component substrate38can have a length or width (or both) of, for example no greater than 1 mm, no greater than 500 microns, no greater than 250 microns, no greater than 100 microns, no greater than 50 microns. Component substrate38can have a thickness no greater than 50 microns, no greater than 20 microns, no greater than 15 microns, no greater than 12 microns, no greater than 10 microns, and no greater than 5 microns. In some embodiments, component substrate has a thickness from 10 microns to 15 microns, e.g., 12 microns. According to some embodiments, a hybrid document10includes a plurality of components36each comprising a respective component substrate38and a respective circuit42, for example that includes a respective controller40, respective power component62, and one or more respective light-emitting diodes30. Each circuit42is disposed on a different component substrate38and each component36and component substrate38is independent and separate from any other component36and component substrate38and can operate or function independently, for example respective power components62can be activated (e.g., pressed) independently based on components36being spatially distributed over document20. In some embodiments, respective independent and spatially separated power components62can be activated at the same time, for example by a motion of hybrid document10. Each separate and independent component substrate38with a corresponding circuit42disposed therein or thereon (comprising an individual and separate component36) can be disposed on document surface24or otherwise disposed in or on document20, for example in a defined area, randomly over a defined area, or in a pattern forming a graphic in a defined area.

Certain embodiments, such as those illustrated inFIG. 30, comprise a single component36that can be disposed, for example by micro-transfer printing, onto document20, for example on document surface24. Documents20can have a locally non-planar, three-dimensional topographical structure (e.g., such as in a typical cloth or paper structure, which is locally rough though macroscopically planar) and components36can be disposed anywhere on document surface24or in document20, for example on or in security structures (e.g., threads, ribbons70, cavities, foils, seals, stamps, or patches) that are disposed on or in (e.g., integrated with, embedded in, affixed to, or applied to) document20, and not necessarily on or directly on document surface24. Thus, in some embodiments, components36, including power components62, light-emitting diodes30, controllers40, and capacitor(s)67, if present, are disposed on or in security structures (e.g., in a one to one correspondence or several to one correspondence, for example spatially distributed over a security structure) prior to disposing the security structure on or in document10, which may simplify manufacturing processes or align with current manufacturing processes such that significant retooling is not necessary.

Piezoelectric cantilever72can be a single cantilever (e.g., as shown inFIG. 30andFIG. 32discussed subsequently) or can comprise separated cantilever fingers and (optionally) a mass73disposed thereon at an end of the fingers opposite power support74to which the fingers of piezoelectric cantilever72are affixed (e.g., as shown inFIGS. 31A-B). The use of fingers of a predetermined length and width and a mass73enables the stiffness and mass of piezoelectric cantilever72to be adjusted to a desired flexibility and oscillation frequency corresponding to a desired method of operation. Mass73can comprise a part of piezoelectric cantilever72or can be separate and can comprise similar material and structure as the remainder of piezoelectric cantilever72or a different material and structure, e.g., a dielectric such as silicon dioxide or silicon nitride. Each finger can have a separate mass73disposed on an end thereof or a common mass73can be disposed across some or all fingers at common ends thereof.

As shown inFIG. 31B(and inFIG. 31A), according to some embodiments of the present disclosure, power component62is disposed over a cavity79in component substrate38. Cavity79can provide space for piezoelectric cantilever72to oscillate in oscillation direction78while remaining protected from the ambient environment.

According to some embodiments, component36comprises a component tether37, for example extending from a component substrate38thereof, controller40comprises a controller tether65, iLED30comprises an LED tether31, capacitor67can have a capacitor tether (not shown in the Figures), or any one or combination of these. In some embodiments, any one or more of controller40, iLED30, and capacitor67can be micro-transfer printed from a corresponding source wafer to component substrate38. Furthermore, component substrate38or component36can be micro-transfer printed from a component source wafer39to document20, as discussed further below. Thus, if present, any one or more of component tether37, controller tether65, LED tether31, or a capacitor tether, can be a fractured or separated tether.

As shown inFIG. 32, according to some embodiments of the present disclosure, a piezoelectric cantilever72with piezoelectric material71and first and second electrodes54,56was constructed. According to some embodiments, mechanically stimulated piezoelectric cantilever72generates electrical power that is transmitted from first and second electrodes54,56. An example of a piezoelectric cantilever72operating to generate power is shown by the oscilloscope traces ofFIG. 33showing output voltage versus time from initial mechanical stimulation for an embodiment of piezoelectric cantilever72. According to some embodiments, constructed piezoelectric cantilevers72with lengths and widths no greater than 100-1000 microns can respond to suitable mechanical stimulation (e.g., by mechanical movement of power component62) by providing electrical current at 1-50 mV (e.g., 2-20 mV). By using a piezoelectric cantilever72in particular, as opposed to other arrangements of piezoelectric power generation components, mechanical deformation that causes power to be generated due to voltage can be imparted without having to directly physically interact with piezoelectric cantilever72. That is, mechanical movement of hybrid document10, such as by rapid movement followed by movement cessation of hybrid document10, can be sufficient to cause deformation of the cantilever that leads to a short term oscillation of the cantilever that can generate sufficient power to operate light-emitting diode30. It is thus not necessary to directly deform piezoelectric cantilever72, which could be practically difficult (e.g., to apply force in a very precise location) or even damage the cantilever (e.g., if too much force were applied). Moreover, piezoelectric cantilever72can be enclosed in a cavity79to further protect from damage while maintaining operability of the oscillation-based power generation mechanism.

In operation, hybrid document10with piezoelectric cantilever72is mechanically stimulated (e.g., physically moved), in order to cause piezoelectric cantilever72to move. Piezoelectric material71in piezoelectric cantilever72is mechanically stressed (e.g., by bending caused by power component62movement) in response to the physical movement and makes electrical power transmitted through first and second electrodes54,56and provided to controller40and light-emitting diodes30, and optionally capacitor(s)67, causing iLEDs30to emit light88. In some embodiments of the present disclosure, light88is emitted immediately, for example without a perceptible delay between the physical movement and the light emission, for example no greater than 100 milliseconds, no greater than 50 milliseconds, no greater than 1 millisecond, no greater than 500 microseconds, no greater than 100 microseconds, or no greater than 10 microseconds.

As shown inFIGS. 34A-34Cand the flow diagram ofFIG. 35, according to some embodiments, a method of operating a hybrid document10comprises providing a flexible hybrid document10with opposing first and second ends in step400, for example in a lengthwise direction longer than a width direction, grasping hybrid document10at the first end and at the second end (e.g., with fingers of different hands) wherein the first end is separated from the second end or separating the first end from the second end to horizontally flatten hybrid document10in step410and as shown inFIG. 34A, moving the first end and the second end closer together in a horizontal direction so that hybrid document10is at least partially folded or bent in a vertical direction in step420as shown inFIG. 34Bwith the movement indicated by the arrows (or in some embodiments movement in a vertical direction is downward, opposite toFIG. 34B, not shown), moving the first end and the second end apart in step430, for example to flatten hybrid document10in a horizontal direction again as shown inFIG. 34Cwith the movement indicated by the arrows, thereby causing component36to move in a vertical direction and mechanically stimulating piezoelectric cantilever72, causing iLED30to emit light88, and in step440observing light88. Light88can also be emitted after step420but can be more difficult to observe on a folded document surface24than a flatted document surface24in step440. In some embodiments, grasping comprises grasping with one or more fingers of one or more hands. In some embodiments, light88is emitted with no perceptible delay between moving the first end and the second end apart (in step430) and light88emission in step440. An immediately observed light emission is enabled by grasping hybrid document10at locations spatially remote from a location of light-emitting diode(s)30, so that for example light88emitted from iLED30is not obscured by grasping or pressing fingers.

Hybrid document10can be flattened in step410in a substantially or partially horizontal plane. By moving first and second ends together in step420, a central portion26of hybrid document10is moved substantially or partially vertically (e.g., up as shown inFIG. 34Bor down). By disposing component36in a central portion26of hybrid document10closer to a center of hybrid document10than to an edge of hybrid document10, component36is likewise moved in a vertical direction. By locating cantilever plane substantially parallel to document surface24, piezoelectric cantilever72can likewise move in a vertical direction so that when the first and second ends of hybrid document10are moved apart in step430, piezoelectric cantilever72moves vertically (e.g., thereby causing oscillation), generating electrical power that is processed and controlled to cause iLED(s)30to emit light88. Horizontal and vertical directions are arbitrary designations; hybrid document10can be grasped in any orientation, so long as the movement of the ends causes power component62to accelerate or decelerate.

Step420shown inFIG. 34Bcan be performed relatively slowly and step430shown inFIG. 34Ccan be performed relatively rapidly. Thus, piezoelectric cantilever72can be mostly at rest after step420but, after the sudden motion of step430, piezoelectric cantilever72is rapidly accelerated and, according to Newton's first law of motion, piezoelectric cantilever72will resist the motion with respect to power support74and will therefore bend, compressing piezoelectric material71and generating electrical power. Furthermore, the sudden cessation of motion after step430will cause further piezoelectric cantilever72motion as power support74suddenly decelerates. This piezoelectric cantilever72motion can be an oscillation that continues to move piezoelectric cantilever72after step430and generates additional electrical power even after step430is complete.

According to some embodiments of the present disclosure and as illustrated inFIGS. 36A-36Gand the flow diagram ofFIG. 37, a method of making hybrid document10comprises providing a component substrate38on a component source wafer39in step500and as shown inFIG. 36A; depositing in step510as shown inFIG. 36Band patterning in step520as shown inFIG. 36C, a first electrode54, piezoelectric material71, and a second electrode56on component substrate38; depositing and patterning a power support74in contact with piezoelectric material71on component substrate38in step530as shown inFIG. 36D; releasing first electrode54, piezoelectric material71, and second electrode56from component substrate38in step540and as shown inFIG. 3Eto form a released piezoelectric cantilever72(e.g., by pattern-wise etching component substrate38with an etchant such as TMAH or KOH at an elevated temperature such as 50-100 degrees C., 60-90 degrees C. or 70-80 degrees C.); and capping released piezoelectric cantilever72in step550with cap75and as shown inFIG. 36F. In some embodiments, capacitor(s)67are formed as part of the construction process for piezoelectric cantilever72on component substrate38in common deposition and patterning steps and with common materials. In some embodiments, rather than forming capacitor(s)67as part of the construction process for piezoelectric cantilever72, capacitor(s)67are separately formed on component substrate38or disposed on component substrate38, for example by micro-transfer printing. iLEDs30and controller40can be micro-transfer printed to component substrate38and electrically connected using photolithographic processes to form component36in step560. Completed component36can be further processed, for example component substrate38can be thinned (e.g., by grinding, etching, or chemical polishing) and multiple components36on component substrate38can be singulated, e.g., by dicing, diamond cutting, or laser cutting, such that they are separate and individual, and disposed in step570on one or more documents20(e.g., document surface24) to form hybrid document(s)10, as shown inFIG. 36G(where a single component36is on single document20). Component36can be disposed on (e.g., adhered to) document20or to a security structure (e.g., ribbon70) and the security structure can be disposed on or in (e.g., adhered to) document20, for example during a process of forming document20(e.g., a papermaking process).

Additional layers and structures can be provided for component36, for example dielectric layers electrically insulating first or second electrodes54,56from component substrate38and can remain on first or second electrodes54,56after under-etching piezoelectric cantilever72from component substrate38to form cavity79(e.g., in step540). Cap75can be provided to enclose cavity79. Cap75can be disposed on (e.g., adhered to) power support74and, if present, one or more other side walls disposed by power support74(e.g., as shown inFIGS. 36F-G). Cap75can include one or more side walls (not shown). Component substrate38can be a semiconductor-on-insulator (SOI) wafer with a bulk substrate, a buried oxide layer, and an epitaxial layer. A dielectric layer can be disposed on the epitaxial layer, the structures ofFIGS. 36B-36Dformed on the dielectric layer, and the epitaxial layer etched to form cavity79. The SOI component substrate38can then be processed as described to disposed component36on document20.

In some embodiments and as illustrated inFIGS. 40A-40FandFIGS. 38 and 39, piezoelectric cantilever72(and optionally capacitor(s)67) are transferred to an intermediate substrate39(e.g., a silicon, inorganic dielectric, or dielectric substrate) and iLEDs30and controller40(and optionally capacitor(s)67) disposed and electrically connected on intermediate substrate39. As shown inFIG. 40A, an encapsulation layer58(e.g., silicon dioxide or silicon nitride) providing a tether37and anchor35is disposed over cap75and any other elements of component36present on component substrate38. Component substrate38is then etched to release the elements of component36present on component substrate38(e.g., piezoelectric cantilever72), as shown inFIG. 40B. An intermediate substrate39(e.g., an SOI wafer with a bulk layer59A, a buried oxide layer59B, and an epitaxial layer50C) is provided with a cavity79(e.g., by etching epitaxial layer59C) as shown inFIG. 40Cand the release elements are transfer printed to an intermediate substrate39(as shown inFIG. 40Dand step555ofFIG. 38). Any further processing of component36is performed (e.g., disposing any further components such as one or more of controller40and iLED(s)30and wires52) in step565and the completed component36is under-etched to release it from intermediate substrate59, as shown inFIG. 40E. The buried oxide layer can provide an etch stop for an anisotropic etch process in bulk layer59A that releases component36from bulk layer59A. Thus, piezoelectric cantilever72can be first transfer printed from a source wafer to an intermediate wafer59. Released completed component36can then be disposed in a second transfer step onto document20or a security structure (e.g., ribbon70or thread) subsequently incorporated into document20, for example by micro-transfer printing and as shown inFIG. 40F. When a process is used to release and print component36(e.g., portion thereof), from component substrate38and dispose (e.g., print) component36(e.g., portion thereof) on intermediate substrate59, intermediate substrate59can itself act as a component substrate38. In some embodiments, a portion of intermediate substrate59(e.g., a bulk layer59A) is separated by laser ablation or grinding to reduce a thickness of component36making it suitable for disposing on or in document20. As shown inFIG. 39, in some embodiments, cap75can be disposed in step550after component36is disposed on intermediate substrate38.

By providing intermediate substrate59and etching it to release component36, thin components36can be provided without back grinding or etching component substrate38, reducing manufacturing costs and risk of damage to component36.

According to some embodiments of the present disclosure and as shown inFIG. 25, component36comprises a plurality of power components62. The power components62can be electrically connected in parallel to increase the current available to component36or can be electrically connected in series to increase the voltage available to component36, for example as shown inFIG. 25. Similarly, fingers of piezoelectric cantilever72can be electrically connected in series or in parallel (or connected in series within groups that are then connected to each other in parallel) for the same reasons. iLEDs30can operate with currents of a few micro-amps and voltages of 0.5 to 5 volts, for example 2.2 volts and 5 micro-amps. Thus, by suitably electrically connecting piezoelectric cantilever72fingers and multiple power components62, with or without capacitor(s)67, electrical power of the appropriate voltage and current can be provided to controller40and iLEDs30.

A component source wafer39can be any wafer, for example an SOI wafer or wafers as are found in the integrated circuit arts, that can be suitably processed to construct component36and from which component36can be released and optionally disposed on intermediate substrate59or document20, for example by micro-transfer printing. In some embodiments, a semiconductor (e.g., silicon) wafer or a dielectric (e.g., glass or polymer) wafer can be used. First and second electrodes54,56can be a metal or other electrical conductors, piezoelectric material71can be KNN or PZT or other piezoelectric material71and can be deposited using photolithographic methods, for example evaporation or sputtering, and can be patterned using photolithographic methods and materials, for example photoresist deposition, exposure to patterned electromagnetic radiation, pattern-wise etching, and stripping. Power support74can be an organic or inorganic dielectric (e.g., a polymer or silicon dioxide) patterned and can be similarly patterned using photolithographic methods and materials. Power support74can be constructed before, after, or as part of the process steps used to construct and pattern first and second electrodes54,56or piezoelectric material71or both. Power support74can be disposed adjacent to piezoelectric cantilever72(e.g., as shown inFIGS. 30, 31B, and 40F) or can be disposed under an end of piezoelectric cantilever72(e.g., forming an L-shape with piezoelectric cantilever72extending further horizontally than power support74extends vertically) (not shown). Capacitor(s)67can also be constructed with similar or the same materials and in common step(s) with first and second electrodes54,56or piezoelectric material71or both or can be constructed or disposed separately. For example, capacitor(s)67can comprise a first electrode54, a second electrode56, and piezoelectric material71between first and second electrodes54,56in a common layer with piezoelectric cantilever72and as shown inFIG. 36C. Controller40and inorganic light-emitting diodes30can be disposed on component substrate38, for example by micro-transfer printing, and electrically connected with wires52, for example using photolithographic methods and materials.

First and second electrodes54,56and piezoelectric material71can be released by etching component substrate38beneath first and second electrodes54,56and piezoelectric material71, for example by anisotropically etching (e.g., a silicon component substrate38) or by etching a sacrificial oxide (buried oxide) layer disposed on or as a part of component substrate38and over which first and second electrodes54,56and piezoelectric material71are disposed, for example with TMAH or KOH.

Cap75can be disposed on and adhered to power support(s)74, for example by micro-transfer printing cap75onto power support(s)74with an adhesive layer. Cap75can comprise a cap tether. Cap75can, for example, be disposed on power support74and one or more other side wall structures to enclose piezoelectric cantilever72in cavity79or can itself include one or more side walls and be disposed over piezoelectric cantilever72(and optionally power support74) to enclose cavity79.

One of ordinary skill in the art will appreciate that throughout the description where an embodiment or embodiments are described as including one or more “iLEDs,” “light-emitting diodes,” or “inorganic light-emitting diodes,” analogous embodiments are contemplated where other light-controlling elements are used instead, making any needed modifications necessary or desirable for operability to be maintained, for example sizing, orientation, or location of electrodes used to provide power to or otherwise control the light-controlling elements. More specifically, where an “inorganic light-emitting diode” is expressly described, unless otherwise clear from context, other light-emitting diodes can be substituted to form analogous embodiments to the expressly described one(s). Various different light-controlling elements that can be used in embodiments of the disclosure have been described throughout, but the disclosure is not limited thereto.

As is understood by those skilled in the art, the terms “over”, “under”, “above”, “below”, “beneath”, and “on” are relative terms and can be interchanged in reference to different orientations of the layers, elements, and substrates included in the present disclosure. For example, a first layer on a second layer, in some embodiments means a first layer directly on and in contact with a second layer. In other embodiments, a first layer on a second layer can include another layer there between.

Having described certain embodiments, it will now become apparent to one of skill in the art that other embodiments incorporating the concepts of the disclosure may be used. Therefore, the disclosure should not be limited to the described embodiments, but rather should be limited only by the spirit and scope of the following claims.

Throughout the description, where apparatus and systems are described as having, including, or comprising specific components, or where processes and methods are described as having, including, or comprising specific steps, it is contemplated that, additionally, there are apparatus, and systems of the disclosed technology that consist essentially of, or consist of, the recited components, and that there are processes and methods according to the disclosed technology that consist essentially of, or consist of, the recited processing steps.

It should be understood that the order of steps or order for performing certain action is immaterial so long as the disclosed technology remains operable. Moreover, two or more steps or actions in some circumstances can be conducted simultaneously. The invention has been described in detail with particular reference to certain embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention.

PARTS LIST