A light-emitting diode (LED) package assembly includes a substrate. The substrate includes a top surface, a bottom surface and an opening formed through the substrate. The opening includes a first portion adjacent the top surface and a second portion adjacent the bottom surface that is wider than the first portion such that portions of the substrate overhang the second portion of the opening. Pads are provided on a bottom surface of the portions of the substrate that overhang the second portion of the opening. The assembly also includes a hybridized device in the opening. The hybridized device includes a silicon backplane that has a top surface, a bottom surface and interconnects on the top surface. The interconnects are electrically coupled to the pads. The hybridized device also includes an LED array on the top surface of the silicon backplane.

BACKGROUND

Precision control lighting applications may require production and manufacturing of small addressable light-emitting diode (LED) lighting systems. The smaller size of such systems may require unconventional components and manufacturing processes.

SUMMARY

A light-emitting diode (LED) package assembly includes a substrate that has a top surface, a bottom surface and an opening formed through the substrate. The opening includes a first portion adjacent the top surface and a second portion adjacent the bottom surface that is wider than the first portion such that portions of the substrate overhang the second portion of the opening. Pads are provided on a bottom surface of the portions of the substrate that overhang the second portion of the opening. The assembly also includes a hybridized device in the opening. The hybridized device includes a silicon backplane that has a top surface, a bottom surface and interconnects on the top surface. The interconnects are electrically coupled to the pads. The hybridized device also includes an LED array on the top surface of the silicon backplane.

DETAILED DESCRIPTION

Examples of different light illumination systems and/or light emitting diode (“LED”) implementations will be described more fully hereinafter with reference to the accompanying drawings. These examples are not mutually exclusive, and features found in one example may be combined with features found in one or more other examples to achieve additional implementations. Accordingly, it will be understood that the examples shown in the accompanying drawings are provided for illustrative purposes only and they are not intended to limit the disclosure in any way. Like numbers refer to like elements throughout.

It will be understood that, although the terms first, second, third, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms may be used to distinguish one element from another. For example, a first element may be termed a second element and a second element may be termed a first element without departing from the scope of the present invention. As used herein, the term “and/or” may include any and all combinations of one or more of the associated listed items.

Further, whether the LEDs, LED arrays, electrical components and/or electronic components are housed on one, two or more electronics boards may also depend on design constraints and/or application.

Semiconductor light emitting devices (LEDs) or optical power emitting devices, such as devices that emit ultraviolet (UV) or infrared (IR) optical power, are among the most efficient light sources currently available. These devices (hereinafter “LEDs”), may include light emitting diodes, resonant cavity light emitting diodes, vertical cavity laser diodes, edge emitting lasers, or the like. Due to their compact size and lower power requirements, for example, LEDs may be attractive candidates for many different applications. For example, they may be used as light sources (e.g., flash lights and camera flashes) for handheld battery-powered devices, such as cameras and cell phones. They may also be used, for example, for automotive lighting, heads up display (HUD) lighting, horticultural lighting, street lighting, torch for video, general illumination (e.g., home, shop, office and studio lighting, theater/stage lighting and architectural lighting), augmented reality (AR) lighting, virtual reality (VR) lighting, as back lights for displays, and IR spectroscopy. A single LED may provide light that is less bright than an incandescent light source, and, therefore, multi-junction devices or arrays of LEDs (such as monolithic LED arrays, micro LED arrays, etc.) may be used for applications where more brightness is desired or required.

LEDs may be arranged into arrays for some applications. For example, LED arrays may support applications that benefit from fine-grained intensity, spatial, and temporal control of light distribution. This may include, but is not limited to, precise spatial patterning of emitted light from pixel blocks or individual pixels. Depending on the application, emitted light may be spectrally distinct, adaptive over time and/or environmentally responsive. LED arrays may provide pre-programmed light distribution in various intensity, spatial or temporal patterns. The emitted light may be based at least in part on received sensor data and may be used for optical wireless communications. Associated electronics and optics may be distinct at an emitter, emitter block or device level.

LED arrays may be formed from one, two or three dimensional arrays of LEDs, VCSELs, OLEDs, or other controllable light emitting systems. LED arrays may be formed as emitter arrays on a monolithic substrate, formed by partial or complete segmentation of a substrate, formed using photolithographic, additive, or subtractive processing, or formed through assembly using pick and place or other suitable mechanical placement. LED arrays may be uniformly laid out in a grid pattern, or, alternatively, may be positioned to define geometric structures, curves, random, or irregular layouts.

FIG.1is a top view of an example LED array101. In the example illustrated inFIG.1, the LED array101is an array of emitters111. Emitters111in the LED array101may be individually addressable or may be addressable in groups/subsets.

An exploded view of a 3×3 portion of the LED array101is also shown inFIG.1. As shown in the 3×3 portion exploded view, the LED array101may include emitters111that each have a width w1. In embodiments, the width w1may be approximately 100 μm or less (e.g., 40 μm). Lanes113between the emitters111may be a width, w2, wide. In embodiments, the width w2may be approximately 20 μm or less (e.g., 5 μm). In some embodiments, the width w2may be as small as 1 μm. The lanes113may provide an air gap between adjacent emitters or may contain other material. A distance D1from the center of one emitter111to the center of an adjacent emitter111may be approximately 120 μm or less (e.g., 45 μm). It will be understood that the widths and distances provided herein are examples only and that actual widths and/or dimensions may vary.

It will be understood that, although rectangular emitters arranged in a symmetric matrix are shown inFIG.1, emitters of any shape and arrangement may be applied to the embodiments described herein. For example, the LED array101ofFIG.1may include over 20,000 emitters in any applicable arrangement, such as a 200×100 matrix, a symmetric matrix, a non-symmetric matrix, or the like. It will also be understood that multiple sets of emitters, matrixes, and/or boards may be arranged in any applicable format to implement the embodiments described herein.

As mentioned above, LED arrays, such as the LED array101, may include up to 20,000 or more emitters. Such arrays may have a surface area of 90 mm2or greater and may require significant power to power them, such as 60 watts or more. An LED array such as this may be referred to as a micro LED array or simply a micro LED. In some embodiments, micro LEDs may include hundreds, thousands or even millions of LEDs or emitters positioned together on centimeter scale area substrates or smaller. A micro LED may include an array of individual emitters provided on a substrate or may be a single silicon wafer or die partially or fully divided into segments that form the emitters.

A controller may be coupled to selectively power subgroups of emitters in an LED array to provide different light beam patterns. At least some of the emitters in the LED array may be individually controlled through connected electrical traces. In other embodiments, groups or subgroups of emitters may be controlled together. In some embodiments, the emitters may have distinct non-white colors. For example, at least four of the emitters may be RGBY groupings of emitters.

LED array luminaires may include light fixtures, which may be programmed to project different lighting patterns based on selective emitter activation and intensity control. Such luminaires may deliver multiple controllable beam patterns from a single lighting device using no moving parts. Typically, this is done by adjusting the brightness of individual LEDs in a 1D or 2D array. Optics, whether shared or individual, may optionally direct the light onto specific target areas. In some embodiments, the height of the LEDs, their supporting substrate and electrical traces, and associated micro-optics may be less than5millimeters.

LED arrays, including LED or μLED arrays, may be used to selectively and adaptively illuminate buildings or areas for improved visual display or to reduce lighting costs. In addition, such LED arrays may be used to project media facades for decorative motion or video effects. In conjunction with tracking sensors and/or cameras, selective illumination of areas around pedestrians may be possible. Spectrally distinct emitters may be used to adjust the color temperature of lighting, as well as support wavelength specific horticultural illumination.

Street lighting is an important application that may greatly benefit from use of LED arrays. A single type of LED array may be used to mimic various street light types, allowing, for example, switching between a Type I linear street light and a Type IV semicircular street light by appropriate activation or deactivation of selected emitters. In addition, street lighting costs may be lowered by adjusting light beam intensity or distribution according to environmental conditions or time of use. For example, light intensity and area of distribution may be reduced when pedestrians are not present. If emitters are spectrally distinct, the color temperature of the light may be adjusted according to respective daylight, twilight, or night conditions.

LED arrays are also well suited for supporting applications requiring direct or projected displays. For example, warning, emergency, or informational signs may all be displayed or projected using LED arrays. This allows, for example, color changing or flashing exit signs to be projected. If an LED array includes a large number of emitters, textual or numerical information may be presented. Directional arrows or similar indicators may also be provided.

Vehicle headlamps are an LED array application that may require a large number of pixels and a high data refresh rate. Automotive headlights that actively illuminate only selected sections of a roadway may be used to reduce problems associated with glare or dazzling of oncoming drivers. Using infrared cameras as sensors, LED arrays may activate only those emitters needed to illuminate the roadway while deactivating emitters that may dazzle pedestrians or drivers of oncoming vehicles. In addition, off-road pedestrians, animals, or signs may be selectively illuminated to improve driver environmental awareness. If emitters are spectrally distinct, the color temperature of the light may be adjusted according to respective daylight, twilight, or night conditions. Some emitters may be used for optical wireless vehicle to vehicle communication.

To individually drive or control the individual LEDs or emitters in the array, a silicon backplane may be provided in close proximity to the LED array. In some embodiments, the silicon backplane may include circuitry to receive power from one or more sources to power various portions of the silicon backplane, circuitry to receive image input from one or more sources for displaying an image via the LED array, circuitry for communications between the silicon backplane and external controllers (e.g., vehicle headlamp controls, general lighting controls, etc.), circuitry for generating a signal, such as a pulse width modulated (PWM) signal, for controlling operation of the individual LEDs or emitters in the array based on, for example, received image input and communications received from external sources and a number of LED drivers for individually driving the LEDs or emitters in the array based on the generated signal. In embodiments, the silicon backplane may be a complementary metal-oxide-semiconductor (CMOS) backplane, which may include the same number of drivers as LEDs or emitters in a corresponding LED array. In some embodiments, the silicon backplane may be an application specific integrated circuit (ASIC). In some embodiments, one driver may be provided for each group of some number of LEDs or emitters and control may be of groups of LEDs or emitters rather than individual. Each driver may be electrically coupled individually to the corresponding LED or emitter or groups of LEDs or emitters. While the silicon backplane is described above with respect to particular circuitry, one of ordinary skill in the art will understand that a silicon backplane used for driving an LED array, such as described herein, may include more, less or different components that potentially carry out different functions without departing from the embodiments described herein.

As mentioned above, the individual drivers in the silicon backplane may be electrically coupled to individual LEDs or emitters or groups of LEDs or emitters in the LED array. As such, the LED array must be placed in close proximity to the silicon backplane. In embodiments, this may be accomplished by individually coupling copper pillar bumps or other connectors in an array of copper pillar bumps or connectors on a surface of the LED array to corresponding connectors on an opposing surface of the silicon backplane. A silicon backplane, such as described above, may become extremely hot during operation, particularly given its close proximity to the LED array. Accordingly, heat dissipation can be challenging for such devices. While some solutions are known for heat dissipation for semiconductor devices, such solutions often include structures that dissipate heat through the top of the device. Due to light-emission from the LED arrays, however, heat dissipation through the top of the device may not be practical or possible. Embodiments described herein provide for structures that may enable effective and efficient heat dissipation through the bottom surface of the device.

Additionally, an LED array, such as the LED array101, and the associated silicon backplane, may require a number of passive elements, such as resistors, capacitors, and crystals, to be placed on a circuit board in close proximity to the silicon backplane. In addition to providing heat dissipation through the bottom surface of the device, embodiments described herein may also provide for an LED package that enables placement of a large number of passive components (e.g., 27 or more) on a top surface of the circuit board and in close proximity to the backplane and LED array. Further, embodiments described herein may provide for a low profile LED array package that may accommodate one or more passive elements and enable dissipation of heat generated by the silicon backplane and the LED array.

FIG.2Ais a cross-sectional view of an example hybridized device210. In the example illustrated inFIG.2A, the hybridized device210includes a silicon backplane214. A first surface213of an LED array212, such as a μLED, may be mounted on a first surface215of the silicon backplane214. The first surface215of the silicon backplane214may also be referred to herein as a top surface, and the first surface213of the LED array214may also be referred to herein as a bottom surface, for simplicity of description. However, one of ordinary skill in the art will understand that the first surface215may be a bottom surface if the hybridized device210is turned upside, a side surface if the hybridized device210is turned sideways, etc. Similarly, the first surface213may be become a top surface if the hybridized device210is turned upside down, a side surface if the hybridized device is210is turned sideways, etc. As mentioned above, an array of connectors (not shown) on the first surface215of the silicon backplane214may be soldered, reflowed or otherwise electrically and mechanically coupled to an array of connectors on the bottom surface of the LED array212. The array of connectors may be any array of connectors, such as an array of copper pillar bumps. The LED array212may have a depth D2. In embodiments, the depth D2 may be, for example, between 5 and 250 μm. The silicon backplane214may have a depth D3. In embodiments, the depth D2 may be, for example, between 100 μm and 1 mm. The hybridized device210may also be referred to as a hybridized die.

FIG.2Bis a cross-sectional view of an example LED package assembly100incorporating the example hybridized device210ofFIG.2A. In the example illustrated inFIG.2B, the hybridized device210is packaged in a packaging substrate102. The LED package assembly100may utilize flipchip interconnects for one or more interconnections as described further herein and may be implemented in a lighting system, such as with a light (such as a vehicle headlight and/or other lights) and/or a display system (such as a computer display, a television display, and/or other displays).

The substrate102may include or be formed from a core material. For example, the substrate102may be a high-density organic substrate, such as a glass-reinforced epoxy laminate material substrate including FR-4 substrate material. The substrate102may include one or more electrically-conductive elements, such as conductive layers, traces, vias, pads, or some combination thereof (not shown). The electrically-conductive elements may be interspersed within the core material, and may provide for conduction of electricity through the substrate102and/or provide for coupling of other elements to the substrate. In some embodiments, the substrate102may have a thickness112of approximately (within 0.1 millimeter (mm)) 1 mm.

The substrate102may have an aperture104formed in or through the substrate102and a recess106that extends into the substrate102. The aperture104and the recess106may be collectively referred to herein as an opening or a cavity with the aperture and recess being referred to as first and second portions of the opening. The aperture104may be located at a first side108of the substrate102. The recess106may extend into the substrate102from a second side110and may abut the aperture104. In particular, the recess106may extend from the second side110and extend partially through the substrate102. The aperture104may extend from the first side108of the substrate102to the recess106, thereby having the aperture104connected with the recess106. The recess106may have a width114, and the aperture104may have a width116, where the width114of the recess106is greater than the width116of the aperture104. The substrate102may include an intermediate surface118located between a first or top surface120of the substrate102and a second or bottom surface122of the substrate102. The intermediate surface118may abut the recess106and overhang the recess. In some embodiments, the intermediate surface118may be substantially (within 10 degrees) parallel with the first surface120and/or the second surface122. The intermediate surface118may be approximately (within 10 μm) 500 μm from the first surface120, where a portion of the substrate102located between the intermediate surface118and the first surface120may have a thickness142of approximately (within 10 μm) 500 μm. Further, the intermediate surface118may extend for a length144of approximately (within 0.1 mm) 1.027 mm from the sides146of the recess106. The intermediate surface118may be formed by the difference between the width114of the recess106and the width116of the aperture104.

The substrate102may include one or more pads124located at the intermediate surface118. The pads124may abut the recess106and may be utilized for coupling components to the substrate102at the intermediate surface118. The pads124may be formed of electrically-conductive material (such as copper, silver, aluminum, alloys thereof, and/or combinations thereof) and may be coupled to other electrically-conductive elements of the substrate. Accordingly, the pads124may provide electrical coupling with components coupled to the substrate102via the pads124.

The substrate102may further include one or more pads126located at the second surface122of the substrate102. In some embodiments, the pads126may comprise an array of pads. For example, the pads126may comprise a land-grid array (LGA) in some embodiments. In other embodiments, the pads126may comprise a ball grid array (BGA). The pads126may be utilized for electrical coupling of the substrate102to an external circuit board. In embodiments, the pads126may be coupled to other electrically-conductive elements of the substrate, the LED array212, and/or the silicon backplane214to create an electrical connection between the external circuit board, electronic components provided on the substrate102, the LED array212and/or the silicon backplane214.

The LED package assembly100may further include one or more electronic components128mounted to the first surface120of the substrate102. In some embodiments, the electronic components128may be passive components, such as resistors, capacitors, inductors, other passive components, or some combination thereof. In other embodiments, the electronic components128may comprise passive components, active components, or some combination thereof. The electronic components128may be coupled to one or more of the electrically-conductive elements of the substrate102and, thereby, also to one or more of the pads126, the silicon backplane214, the LED array214and/or other electronic components128.

The hybridized device210may be coupled to the substrate102and may also be electrically coupled to one or more of the electronic components128and the pads126via electrically-conductive elements of the substrate102. The silicon backplane214may be coupled to the substrate102via the pads124. The silicon backplane214may be located partially or entirely within the recess106. In some embodiments, the silicon backplane214may have a thickness140of approximately (within 10 micrometers (μm)) 725 μm, and the silicon backplane214may extend out of the recess106past the second surface122of the substrate102by approximately (within 10 μm) 325 μm. In some embodiments, the silicon backplane214may have a thickness between 300 microns and 750 microns. Further, sides156of the silicon backplane214may be located approximately (within 10 μm) 500 μm from the sides146of the recess106in some embodiments. The LED die212may be coupled to the first side136of the silicon backplane214and may be located between the first surface120of the substrate102and the silicon backplane214. In some embodiments, the LED die212may be partially located within the aperture104.

LEDs or segments of the LED array212may be directed through the aperture104, and light emitted by the LEDs or segments may be directed through the aperture104. In some embodiments, edges of the LED array212and edges of the first surface120of the substrate102that abut the aperture104may be separated by a certain distance that allows light emitted by the LEDs of the LED array212to be emitted at an angle138to the edges of the LED array212. In some embodiments, the angle138may be approximately (within 10 degrees) 45 degrees. In other embodiments, LED package assembly100may be designed with a different angle138at which the light may be emitted from the LED array212.

The LED package assembly100may further include one or more flipchip interconnects148that couple the hybridized device210to the substrate102. In particular, the flipchip interconnects148may couple the silicon backplane214to the pads124of the substrate102. The flipchip interconnects148may be or include one or more solder bump joints, one or more copper pillar bump joints, or some combination thereof. The flipchip interconnects148may be electrically conductive and may electrically couple the silicon backplane214to the substrate102to provide electrical coupling and/or signal exchange between the silicon backplane214and one or more of the electronic components128and the pads126via electrically conductive elements in the substrate102(not shown). In some embodiments, the flipchip interconnects148may maintain a distance between the intermediate surface118and the first side136of the silicon backplane214. For example, the flipchip interconnects148may have a thickness150of approximately (within 10 μm) 100 μm in some embodiments. Further, the flipchip interconnects148may be located at a distance152of approximately (within 10 μm) 340 μm from sides154of the aperture104and/or approximately (within 10 μm) 0.187 μm from the sides156of the silicon backplane214.

Utilizing the flipchip interconnects148to couple the silicon backplane214to the pads124of the substrate102may provide one or more advantages over other means of coupling. For example, the flipchip interconnects148may provide better thermal performance. Further, the flipchip interconnects148may provide for smaller pitch interconnects, which may allow for higher density of interconnects. One having ordinary skill in the art may recognize additional advantages to utilizing the flipchip interconnects148.

The LED package assembly100may further include an underfill material158that may cover at least the flipchip interconnects148. For example, the underfill material158may encircle each of the flipchip interconnects148and prevent the flipchip interconnects148from being exposed. The underfill material158may be or include an electrically-insulating material, which may prevent shorting between the flipchip interconnects148or between the flipchip interconnects148and other electrically-conductive elements in some embodiments. Further, the underfill material158may provide physical support for the coupling between the silicon backplane132and the substrate102. In some embodiments, the underfill material158may be omitted. In other embodiments, the underfill material158may cover a larger surface area than is shown inFIG.2Bby, for example, filling more of the empty space between the hybridized device210and the substrate102.

The LED package assembly100may include a circuit board160. The circuit board160may be coupled to the substrate102via the pads126. The board160may include circuitry that may provide control signaling and/or other data, such as image data, that may be provided to hybridized device210, where the image data may affect the operation of the LED array212. The circuit board160may include an integrated heatsink164. The integrated heatsink164may be or include a thermally-conductive material, such as copper. The integrated heatsink164may be located adjacent to the silicon backplane214and may be thermally coupled to a second side162of the silicon backplane214, the second side162being opposite from the first side136, and may provide cooling for the silicon backplane214. The direct coupling between the silicon backplane214and the integrated heatsink164may enable better heat dissipation for the hybridized device210and also heat dissipation through the bottom surface of the hybridized device210rather than through the top surface such that efficient heat dissipation may be accomplished without blocking light emission from the LED array212.

FIG.2Cis a top view of the example hybridized device210ofFIGS.2A and2B, according to some embodiments. In the example illustrated inFIG.2C, the hybridized device210includes the LED array212and the silicon backplane214. The silicon backplane210may be coupled to the LED array212, such as being coupled by one or more interconnects (such solder bump joints and/or copper pillar bump joints).

As can be seen inFIG.2C, the silicon backplane214may have a larger footprint than a footprint of the LED array212, thereby having a portion of the silicon backplane214extending outside of the footprint of the LED array212. The silicon backplane214may include one or more pads206. The pads206may be located on the portion of the silicon backplane214extending outside of the footprint of the LED array212and at a surface of the silicon backplane214. The pads206may be coupled to the circuitry within the silicon backplane214and may be utilized for coupling components to the silicon backplane214. For example, the flipchip interconnects148may be coupled to the pads206and may be utilized for coupling the substrate102to the silicon backplane214.

FIG.3is a flow diagram of an example method300of manufacturing an LED package assembly. For example, the procedure300may be used to manufacture the LED package assembly100.

The method300may initiate with a substrate. For example,FIG.4is a cross-sectional view of an example substrate400that may be used for the method300ofFIG.3, according to some embodiments. The substrate400may include one or more of the features of the substrate102. For example, the substrate400may include one or more pads402located at a second surface404of the substrate, where the pads402include one or more of the features of the pads126. Further, the substrate400may include one or more pads406, where the pads406include one or more of the features of the pads124. The pads406may be embedded within the substrate400when the method300is initiated. The substrate400may have been manufactured using a substrate production process, such as a build-up process.

A recess may be formed in the substrate (302). In embodiments, the recess may be formed via a machine cutting process, such as a routing process. In particular, the machine cutting process may be applied to a surface of the substrate to remove a portion of the material from the substrate, thereby forming the recess. The recess formed by the machine cutting process may extend into the substrate from the surface of the substrate to one or more pads embedded within the substrate, where the machine cutting process exposes the pads.

FIG.5is a cross-sectional view of an example product500produced by forming the recess in the substrate according to the method ofFIG.3. A recess502may have been formed in the substrate400via the machine cutting process302. The recess502may include one or more of the features of the recess106. The machine cutting process may have been applied to the second surface404of the substrate400to produce the recess502. The machine cutting process may be applied to a portion of the second surface404located between the pads402. The recess502may extend into the substrate400from the second surface404of the substrate400to the pads406, thereby exposing the pads406. Further, forming the recess502may produce an intermediate surface504of the substrate400, wherein the intermediate surface504includes one or more of the features of the intermediate surface118. For example, the pads406may be located at the intermediate surface504and may be exposed to the recess502.

An aperture may be formed in the substrate (304). The aperture may be formed via a machine cutting process, such as a routing process. In particular, the machine cutting process may be applied to a surface of the substrate to remove a portion of the material from the substrate, thereby forming the aperture through the substrate. The aperture formed may extend from the recess formed through a surface of the substrate at an opposite side of the substrate from the recess.

FIG.6is a cross-sectional view of an example product600produced by forming the aperture in the substrate according to the method ofFIG.3. An aperture602may have been formed through the substrate400via the machine cutting process of stage304. The aperture602may include one or more of the features of the aperture104. The machine cutting process may have been applied to the intermediate surface504or a first surface604of the substrate400to produce the aperture602. The machine cutting process for forming the aperture602may utilize a narrower tool than the machine cutting process for forming the recess502, thereby causing the aperture602to have a narrower width than the recess502. The aperture602may extend through the substrate400from the intermediate surface504to the first surface604. The aperture602may be located between the pads406of the substrate400.

While in the example method illustrated inFIG.3the recess502is illustrated as being formed prior to forming the aperture602, it should be understood that the order may be reversed in other embodiments. In particular, the aperture602may be formed before the recess502in other embodiments. The aperture602may be formed through the substrate400from the first surface604to the second surface404. The recess502may be formed from the second surface404after the aperture602has been formed in the substrate400.

A hybridized device may be positioned in the recess (306). For example, a silicon backplane of the hybridized device may be positioned within the recess of the substrate with an LED array of the hybridized device directed toward the aperture of the substrate. When positioned within the recess, the silicon backplane may be located partially or entirely within the recess. Further, the LED array may be located within the recess and/or may be located partially within the aperture. The LED array may be located between the silicon backplane and the first surface of the substrate. The LED array may be coupled to a surface of the silicon backplane. The silicon backplane may be aligned with the pads of the substrate located at the intermediate surface that abuts the recess, such that the silicon backplane may be coupled to the pads via flipchip interconnects.

FIG.7is a cross-sectional view of an example product700produced by positioning the hybridized device in the substrate according to the method ofFIG.3. In the example illustrated inFIG.7, a hybridized device702is positioned in the recess502of the substrate400. The hybridized device702may include one or more of the features of the integrated LED130. A silicon backplane704of the hybridized device702may be located within the recess502. For example, the silicon backplane704may be located partially or entirely within the recess502. In some embodiments, a portion of the silicon backplane704may extend past the second surface404out of the recess502. An LED array706of the hybridized device702may be coupled to the silicon backplane704and may be directed toward the aperture602. The LED array706may be located within the recess502and/or may be located partially within the aperture602. The LED array706may be located between the silicon backplane704and the first surface604. The silicon backplane704may be aligned with the pads406of the substrate400, such that the silicon backplane704may be coupled to the pads via flipchip interconnects. In particular, portions of the silicon backplane704may be located adjacent to intermediate surface504where the pads406are located.

The hybridized device may be coupled to the substrate via one or more flipchip interconnects (308). For example, the flipchip interconnects may be formed between the pads at the intermediate surface of the substrate and the silicon backplane of the integrated LED. The flipchip interconnects may electrically couple the hybridized device and the substrate. The flipchip interconnects may comprise solder bump joints or copper pillar bump joints. In some embodiments, the flipchip interconnects may be formed by a wave flow process.

FIG.8is a cross-sectional view of an example product800produced by coupling the hybridized device to the substrate via the one or more flipchip interconnects according to the method ofFIG.3. One or more flipchip interconnects802may be formed between the hybridized device702and the substrate400. The flipchip interconnects802may include one or more of the features of the flipchip interconnects148. The flipchip interconnects802may be formed between the silicon backplane704and the pads406at the intermediate surface504of the substrate400. The flipchip interconnects802may electrically couple the silicon backplane704to the pads406and may provide for exchange of signals between the hybridized device702and the substrate400. The flipchip interconnects802may comprise solder bump joints or copper bump joints.

An underfill material may be formed around the flipchip interconnects (310). The underfill material may encompass the flipchip interconnects and prevent the flipchip interconnects from being exposed. The underfill material may provide electrical insulation around the flipchip interconnects, thereby preventing electrical shorting between the flipchip interconnects and/or other electrical components of the LED package assembly. The underfill material may further provide physical support to the flipchip interconnects, thereby helping to maintain physical coupling between the substrate and the integrated LED.

FIG.9is a cross-sectional view of an example product900produced by forming the underfill material around the flipchip interconnects according to the method ofFIG.3. Underfill material902may be formed around the flipchip interconnects802. The underfill material902may include one or more of the features of the underfill material158. The underfill material902may surround each of the flipchip interconnects802, thereby preventing exposure of the flipchip interconnects802. For example, the underfill material902may encircle each of the flipchip interconnects802. The underfill material902may comprise electrical insulation material that can prevent shorting between the flipchip interconnects802and/or other electrical components of the LED package assembly. The underfill material902may extend between the substrate400and the hybridized device702, and may physically couple the substrate400and the hybridized device702. The underfill material902may provide physical support between the substrate400and the hybridized device702. In particular, the underfill material902may assist in maintaining physical coupling between the substrate400and the hybridized device. In other embodiments, the underfill material902may be omitted and stage310, which produces the underfill material902, may be omitted.

Electronic components may be coupled to the substrate (312). For example, electronic components may be coupled to the first surface of the substrate. The electronic components be or include passive components, active components, or some combination thereof.

FIG.10is a cross-sectional view of an example product1000produced by coupling electronic components to the substrate according to the method ofFIG.3. One or more electronic components1002may be coupled to the first surface604of the substrate400. The electronic components1002may include one or more of the features of the electronic components128. The electronic components1002may be electrically coupled to the substrate400, thereby allowing signals to be exchanged between the electronic components and the substrate. In other embodiments, the electronic components1002may be omitted and stage312, which couples the electronic components1002to the substrate400, may be omitted.

A circuit board may be coupled to the substrate (314). In particular, the circuit board may be coupled to pads of the substrate, where the pads are located on a second surface of the substrate. The coupling of the circuit board to the pads of the substrate may maintain the position of the circuit board and provide electrical coupling between the circuit board and the substrate. The circuit board may include an integrated heatsink. The integrated heatsink may be positioned adjacent to the silicon backplane and may be thermally coupled to the silicon backplane. In some embodiments, coupling the circuit board to the substrate may comprise applying a heat transfer compound between the silicon backplane and the integrated heatsink.

FIG.11is a cross-sectional view of an example product1100produced by coupling a circuit board to a substrate according to the method ofFIG.3. In particular, the product1100may be a completed LED package assembly according to some embodiments. A circuit board1102may be coupled to the substrate400. The circuit board1102may include one or more of the features of the circuit board160. In particular, the circuit board1102may be coupled to pads402of the substrate400. The coupling of the circuit board1102with the pads402may maintain a position of the circuit board1102and provide for electrical coupling between the circuit board1102and the substrate400. Further, the substrate400may provide for electrical coupling between the circuit board1102and the hybridized device702. The circuit board1102may include an integrated heatsink1106. The integrated heatsink1106may be positioned against a surface1104of the silicon backplane704, the surface1104of the silicon backplane704being on an opposite side of the silicon backplane704from the hybridized device706. The integrated heatsink1106may be thermally coupled to the silicon backplane704and may facilitate cooling of the hybridized device702. In some embodiments, a heat transfer compound may be applied between the integrated heatsink1106and the silicon backplane704to facilitate heat transfer between the integrated heatsink1106and the hybridized device702. In some embodiments, the integrated heatsink1106may be omitted from the circuit board1102.

FIG.12is a block diagram of an example system1200that includes an LED package assembly1202. For example, the system1200may include a lighting system or a display system that may utilize the LED package assembly1202to provide lighting and/or a display. In some embodiments, the system1200may be or include a headlight for a vehicle, a light, a handheld device (such as a smartphone, a smartwatch, and/or electronic organizer), a display for a system (such as a computer display and/or a television display), or some combination thereof. While components of the system1200are illustrated, it should be understood that the system1200may include additional components and/or alternative components that perform the functions of the described components in some embodiments.

The system1200may include a controller1204. The control1204may determine an image to be displayed by the LEDs of the LED package assembly1202. For example, the controller1204may include or be coupled to a processor that may indicate an image to be displayed by the LEDs or segments. The image may be a user interface, an arrangement of light, an intensity of light, one or more symbols to be displayed by the LEDs, or some combination thereof. The controller1204may generate image data that indicates an image to be displayed by the LEDs and may provide the image data to components of the system1200. The image data may be or include a signal that indicates the image to be produced by the LEDs.

The system1200may include the LED package assembly1202. The LED package assembly1202may include one or more of the features of the LED package assembly100. For example, the LED package assembly1202may include a substrate, such as substrate102, with a hybridized device1206coupled to the substrate via one or more flipchip interconnects, such as the flipchip interconnects148. The hybridized device1206may include one or more of the features of the hybridized device210. For example, the hybridized device1206may include a silicon backplane1208and an LED array1210, where the silicon backplane1208may include one or more of the features of the silicon backplane214and the LED array1210may include one or more of the features of the LED array212. The LED array1210may include one or more LEDs, μLEDs and/or segments that provide light and/or a display for the system1200.

The silicon backplane1208may include a controller1212. The controller1212may be coupled to the controller1204and may receive the image data from the controller1204. The controller1212may determine an image to be displayed by the LEDs of the LED array1210based on the image data received from the controller1204. The controller1212may determine actions to be taken by the LED device1210and the LEDs or segments of the LED array1210to produce the image and may cause the LED array1210and the LEDs or segments of the LED device1210to take the actions. For example, the controller1212may determine when each of the LEDs or segments of the LED array1210are to be turned on to produce the image and may cause the LEDs or segments to be turned on (such as by activating corresponding switches of the silicon backplane2108to cause the LEDs or segments to turn on in accordance with the times that the LEDs or segments are to be turned on. Further, the controller1212may determine the intensity of light to be emitted by the LEDs and/or the color of light to be emitted by the LEDs and may cause the LEDs to emit the determined intensity of light and/or color of light.

FIG.13is a block diagram of another example system1300. In some embodiments, the system1300may be or include a portion of a vehicle headlamp system in some embodiments. For example, the system1300may be or include an active headlamp system in some embodiments, where an intensity of light and/or image of the light output by the system1300may be changed. The system1300, or portions thereof, may reside in a vehicle, in a headlamp of a vehicle, or some combination thereof. The system1300may implement a pixelated configuration made possible by an array of LEDs.

The system1300may be coupled to a bus1302of the vehicle and a power source1304. The power source1304may provide power for the system1300. The bus1302may be coupled to one or more components that can provide data and/or utilize data provided to the system1300. The data provided on the bus1302may be related to environment conditions around the vehicle (such as a time of day, whether there is rain, whether there is fog, ambient light levels, and other environmental data), conditions of the vehicle (such as whether the vehicle is parked, whether the vehicle is in-motion, a current speed of the vehicle, a current direction of travel of the vehicle), and/or presence/positions of other vehicles or pedestrians around the vehicle. The system1300may provide feedback (such as information regarding operation of the system) to the components.

The system1300may further include a sensor module1306. In some embodiments, the sensor module1306may include one or more sensors that can sense surroundings of the vehicle. For example, the one or more sensors may sense surroundings that can affect an image to be produced by light emitted by the system1300. In some embodiments, the sensors may sense environmental conditions around the vehicle, and/or presence/positions of other vehicles or pedestrians around the vehicle. The sensor module1306may operate in combination with the data provided on the bus1302or may operate in lieu of a portion of the data (such as the environment conditions, and/or the presence/positions of the other vehicles or pedestrians) being provided on the bus1302. The sensor module1306may output data indicating what has been sensed by the sensors.

The system1300may further include a transceiver1308. The transceiver1308may have a universal asynchronous receiver-transmitter (UART) interface or a serial peripheral interface (SPI) in some embodiments. The transceiver1308may be coupled to the bus1302and the sensor module1306, and may receive data from the bus1302and the sensor module1306. In some embodiments, the transceiver1308may multiplex the data received from the bus1302and the sensor module1306, and may direct feedback to the bus1302or the sensor module1306.

The system1300may further include a processor1310. The processor1310may be coupled to the transceiver1308and exchange data with the transceiver1308. For example, the processor1310may receive data from the transceiver1308that was provided by the bus1302and/or the sensor module1306. The processor1310may generate image data that indicates an image to be produced by light emitted from the system1300. The processor1310may further generate one or more inquiries that request information from one or more of the components of the system. The processor1310may further provide the feedback to the transceiver1308to be directed to the bus1302or the sensor module1306.

The system1300may further include a headlamp1312of the vehicle. The headlamp1312may be or include an active headlamp in some embodiments, where the active headlamp may produce multiple different outputs of light. The headlamp1312may include a lighting system1314. The lighting system1314may include an LED package assembly, such as the LED package assembly100, or some portion thereof. For example, the lighting system1314may include the substrate102and the hybridized device210in some embodiments. The headlamp1312may be coupled to the processor1310and may exchange data with the processor1310. In particular, the lighting system1314may be coupled to the processor1310and may exchange data with the processor1310. The lighting system1314may receive the image data and inquiries from processor1310and may provide feedback to the processor1310.

The system1300may further include power protection1316. The power protection1316may be coupled to the power source1304and may receive power from the power source. The power protection1316may include one or more filters that may reduce conducted emissions and provide power immunity. In some embodiments, the power protection1316may provide electrostatic discharge (ESD) protection, load-dump protection, alternator field decay protection, reverse polarity protection, or some combination thereof.

The system1300may further include processor power1318. The processor power1318may be coupled to the power protection1316and may receive power from the power source1304. The processor power1318may comprise a low-dropout (LDO) regulator that may generate a power for powering the processor1310from the power provided by the power source1304. The processor power1318may further be coupled to the processor1310and may provide power to the processor1310.

The system1300may further include a power supply1320. The power supply1320may be coupled to the power protection1316and may receive power from the power source1304. In some embodiments, the power supply1320may comprise a converter that converts the power from the power source1304to power for the headlamp1312. For example, the power supply1320may comprise a direct current (DC)-to-DC converter that converts the power from the power supply1320from a first voltage to a second voltage for the lighting system1314of the headlamp1312.

FIG.14is a block diagram of another example lighting system1400, according to some embodiments. For example, the system1300ofFIG.13may include one or more of the features of the lighting system1400. The lighting system1400may be implemented in a headlamp, such as the headlamp1312ofFIG.13.

The lighting system1400may include a control unit1402. The control unit1402may be coupled to a processor such as the processor1310ofFIG.13. The control unit1402may receive image data and inquiries from the processor. The control unit1402may further provide feedback to the processor.

The controller1402may include a digital interface1404. The digital interface1404may facilitate communication with the processor and other components within the lighting system1400. For example, the digital interface1404may be or include an SPI interface in some embodiments, where the SPI interface may facilitate communication.

The control unit1402may further include an image processor1406. The image processor1406may receive the image data via the digital interface1404and may process the image data to produce indications of pulse width modulation (PWM) duty cycles and/or intensities of light for causing the lighting system1400to produce the images indicated by the image data.

The control unit1402may further include a frame buffer1408and a standby image storage1410. The frame buffer1408may receive the indications produced by the image processor1406and store the indications for implementation. The standby image storage1410may further store indications of PWM duty cycles and/or intensities of light. The indications stored in the standby image storage1410may be implemented in the absence of indications stored in the frame buffer1408. For example, the frame buffer1408may retrieve the indications from the standby image storage1410when the frame buffer1408is empty.

The controller1402may further include a PWM generator1412. The PWM generator1412may receive the indications from the frame buffer1408and may produce PWM signals in accordance with the indications. The PWM generator1412may further determine intensities of light based on the indications and produce a signal to cause the intensities of light to be produced.

The lighting system1400may include a μLED array1414. The μLED array1414may include a plurality of pixels, where each of the pixels include a pixel unit1416. In particular, the pixel unit1416may include an LED1418, a PWM switch1420, and a current source1422. The pixel unit1416may receive the signals from the PWM generator1412. The PWM signal from the PWM generator1412may cause the PWM switch1420to open and close in accordance with the value of the PWM signal. The signal corresponding to the intensities of light may cause the current source1422produce a current flow to cause the LED1418to produce the corresponding intensities of light.

The lighting system1400may further include an LED power supply1424. The LED power supply1424may be coupled to the power supply1320ofFIG.13and may receive power from the power supply1320. The LED power supply1424may produce power for the LEDs of the μLED array1414. The LED power supply1424may be coupled to the μLED array1414and may provide the power for the LEDs to the μLED array1414.

FIG.15is an example hardware arrangement1500for implementing the system1300ofFIG.13, according to some embodiments. In particular, the hardware arrangement1500may illustrate hardware components that may implement the system1300.

The hardware arrangement1500may include an LED package assembly1512. The LED package assembly1512may have been produced by the method300ofFIG.3. The LED package assembly1512may include one or more of the features of the LED package assembly100ofFIG.1. For example, the LED package assembly1512may include a hybridized device1508having a silicon backplane1504and an LED array1502. The LED array1502may be coupled to the silicon backplane by one or more interconnects1510, where the interconnects1510may provide for transmission of signals between the LED die1502and the silicon backplane1504. The interconnects1510may comprise one or more solder bump joints, one or more copper pillar bump joints, or some combination thereof.

The LED array1502may also include circuitry to implement the μLED array1414ofFIG.14. In particular, the LED array1502may include a plurality of pixels of the μLED array1414. The LED array1502may include a shared active layer and a shared substrate for the μLED array1414, thereby having the μLED array1414that is a monolithic μLED array. Each pixel of the μLED array1414may include an individual segmented active layer and/or substrate. Accordingly, the LED array1502may be a monolithic die that has a segmented surface with a corresponding pixel of the μLED array1214occupying each segment of the surface. In some embodiments, the LED array1502may further include the PWM switches and the current sources of the μLED array1414. In other embodiments, the PWM switches and the current sources may be included in the silicon backplane1504.

The silicon backplane1504may include circuitry to implement the controller1402ofFIG.14and the LED power supply1424ofFIG.14. The silicon backplane1504may utilize the interconnects1510to provide the μLED array1414with the PWM signals and the signals for the intensity for causing the μLED array1414to produce light in accordance with the PWM signals and the intensity.

The LED package assembly1512may further include a substrate1516. The substrate1516may be coupled to the silicon backplane1504via one or more flipchip interconnects1518. The flipchip interconnects1518may include one or more of the features of the flipchip interconnects148.

The hardware arrangement1500may further include a circuit board1506. The circuit board1506may include one or more of the features of the circuit board160ofFIG.1. The circuit board1506may include circuitry to implement the power protection1316ofFIG.13, the power supply1320ofFIG.13, the processor power1318ofFIG.13, the sensor module1306ofFIG.13, the transceiver1308ofFIG.13), the processor1310ofFIG.13, or portions thereof. The circuit board1506may be coupled to the substrate1516, where the substrate1516may facilitate communication between the circuit board1506and the hybridized device1508. For example, the circuit board1506may be coupled to the substrate1516via pads1520in the illustrated embodiment. The circuit board1506and the silicon backplane1504, via the substrate1516, may exchange image data, power, and/or feedback via the coupling, among other signals.

Having described the embodiments in detail, those skilled in the art will appreciate that, given the present description, modifications may be made to the embodiments described herein without departing from the spirit of the inventive concept. Therefore, it is not intended that the scope of the invention be limited to the specific embodiments illustrated and described.