CN-115136304-B - LED package assembly, vehicle headlamp system, and method of making an LED package assembly

Abstract

A Light Emitting Diode (LED) package assembly (100) includes a substrate (102). The substrate includes a top surface, a bottom surface (122), and an opening formed through the substrate (102). The opening includes a first portion (104) adjacent the top surface and a second portion (106) adjacent the bottom surface (122), the second portion (106) being wider than the first portion (104) such that portions of the substrate (102) overhang the second portion (106) of the opening. The pads (124) are disposed on a bottom surface of portions of the substrate (102) overhanging the second portion (106) of the opening (102). The assembly further includes a mixing device (210) in the opening. The hybrid device (210) includes a silicon backplate (214) having a top surface, a bottom surface, and an interconnect on the top surface. The interconnect (148) is electrically coupled to the pad (124). The hybrid device also includes an LED array (212) on a top surface of the silicon back-plate (214).

Inventors

• T. Y. Xuan
• H.K.Wang

Assignees

• 亮锐有限责任公司

Dates

Publication Date

20260508

Application Date

20201224

Priority Date

20201223

Claims (20)

1. 1. An LED package assembly comprising: a substrate comprising a top surface, a bottom surface, and an opening formed through the substrate, the opening comprising a first portion adjacent the top surface and a second portion adjacent the bottom surface, the second portion being wider than the first portion such that portions of the substrate overhang the second portion of the opening; A plurality of pads on the bottom surface of each portion of the substrate overhanging the second portion of the opening, and A mixing device in the opening, the mixing device comprising: A silicon back plate comprising a top surface, a bottom surface, and a plurality of interconnects on the top surface of the silicon back plate, the silicon back plate being an integrated circuit die, the plurality of interconnects being electrically coupled to the plurality of pads and having a thickness that maintains a predetermined distance between the bottom surface of portions of the substrate overhanging the second portion of the opening and the top surface of the hybrid device, and An LED array on a top surface of the silicon back plate.
2. 2. The LED package assembly of claim 1, wherein the plurality of interconnects comprises at least one of solder bump joints or copper pillar bump joints.
3. 3. The LED package assembly of claim 1, wherein the LED array is between a top surface of the substrate and the silicon back plate.
4. 4. The LED package assembly of claim 1, wherein the entire silicon back plate is within the second portion of the opening.
5. 5. The LED package assembly of claim 1, wherein a portion of the LED array is within the first portion of the opening such that a top surface of the LED array is lower than a top surface of the substrate and an outer edge of the LED array is spaced apart from an inner edge of the substrate adjacent the first portion of the opening in the substrate such that light is emitted at a predetermined angle.
6. 6. The LED package assembly of claim 5, wherein said predetermined angle is 45 °.
7. 7. The LED package assembly of claim 1, further comprising a heat sink thermally coupled to a bottom surface of the silicon back plate.
8. 8. The LED package assembly of claim 1, wherein said LED array is a monolithic array comprising a plurality of light emitting segments.
9. 9. The LED package assembly of claim 1, wherein the predetermined distance is 100 μιη.
10. 10. The LED package assembly of claim 1, further comprising a plurality of contact pads on a bottom surface of the substrate and configured for electrically coupling at least one of a silicon back plane, an LED array, or a passive component on a top surface of the substrate to an external control board.
11. 11. A vehicle headlamp system, comprising: an LED package assembly, comprising: a substrate having a top surface, a bottom surface and a cavity, An integrated circuit die coupled to the substrate by one or more flip-chip interconnects, the integrated circuit die disposed at least partially within the cavity, An LED array coupled to the integrated circuit die, the LED array disposed at least partially between the integrated circuit die and a surface of a substrate positioned opposite the integrated circuit die, and A plurality of contact pads on a bottom surface of the substrate and configured for electrically coupling at least one of an integrated circuit die, an LED array, or a passive component on a top surface of the substrate to an external control board, and A circuit board coupled to the LED package assembly, the circuit board including a processor configured to provide image data to the LED package assembly, the image data being indicative of an image to be displayed by the LED package assembly.
12. 12. The vehicle headlamp system of claim 11, wherein the one or more flip chip interconnects comprise one or more solder bump joints or one or more copper pillar bump joints, the one or more flip chip interconnects electrically coupling the integrated circuit die to one or more pads of the substrate, the one or more flip chip interconnects having a thickness that maintains a predetermined distance between a bottom surface of portions of the substrate overhanging a top surface of the integrated circuit die and the one or more pads adjacent the cavity.
13. 13. The vehicle headlamp system of claim 11, wherein the cavity has a first portion extending from a first surface of the substrate and a second portion extending into the substrate from a second surface of the substrate, the second surface being on an opposite side of the substrate from the first surface, the second portion of the cavity being wider than the first portion of the cavity, and the LED array being between the first surface and the integrated circuit die.
14. 14. The vehicle headlamp system of claim 11, wherein the integrated circuit die is between 300 microns and 750 microns thick.
15. 15. The vehicle headlamp system of claim 11, wherein the integrated circuit die comprises a controller, the LED array comprises one or more LEDs coupled to the controller, and the controller is configured to cause the one or more LEDs to display an image indicated by the image data.
16. 16. The vehicle headlamp system of claim 11, wherein the circuit board comprises an integrated heat spreader in contact with a bottom surface of the integrated circuit die.
17. 17. A method of making an LED package assembly, the method comprising: Forming a hole in a substrate via a top surface of the substrate; Forming a recess in the substrate via a bottom surface of the substrate such that portions of the substrate adjacent the aperture overhang the recess and form an intermediate surface of the substrate; Placing a mixing device at least partially within the recess, and Coupling the hybrid device to the intermediate surface via one or more flip-chip interconnects, the one or more flip-chip interconnects having a thickness that maintains a predetermined distance between the intermediate surface of the substrate and a top surface of the hybrid device, Wherein the hybrid device includes a silicon back-plate that is an integrated circuit die and an LED array coupled to the silicon back-plate.
18. 18. The method of claim 17, wherein coupling the hybrid device to the intermediate surface comprises: Positioning the silicon back plate at least partially within the recess; positioning the LED array at least partially within the aperture, and The one or more flip chip interconnects are formed between the silicon back plate and the intermediate surface.
19. 19. The method of claim 17, wherein forming the recess within the substrate comprises removing a portion of the substrate via a machine dicing process, the removal of the portion of the substrate exposing one or more pads at the intermediate surface, and the one or more flip chip interconnects coupling the silicon backplate to the one or more pads.
20. 20. The method of claim 17, wherein forming the hole in the substrate comprises removing a portion of the substrate via a mechanical cutting process to form the hole.

Description

LED package assembly, vehicle headlamp system, and method of making an LED package assembly Cross-reference to related application(s) The present application claims the benefit of U.S. non-provisional application Ser. No. 17/132359 filed 12/23/2020 and U.S. provisional application Ser. No. 62/954121 filed 12/27/2019, both of which are incorporated herein by reference as if fully set forth herein. Background Precision control lighting applications may require the fabrication and fabrication of small addressable Light Emitting Diode (LED) lighting systems. The smaller size of such a system may require unusual components and manufacturing processes. Disclosure of Invention A Light Emitting Diode (LED) package assembly includes a substrate having 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, the second portion being wider than the first portion such that portions of the substrate overhang the second portion of the opening. The pads are disposed on a bottom surface of portions of the substrate overhanging the second portion of the opening. The assembly further includes a mixing device in the opening. The hybrid device includes a silicon back plate having a top surface, a bottom surface, and an interconnect on the top surface. The interconnect is electrically coupled to the pad. The hybrid device further includes an array of LEDs on the top surface of the silicon back plate. Drawings A more detailed understanding can be obtained from the following description, which is given by way of example in connection with the accompanying drawings, in which: FIG. 1 is a top view of an example LED array; FIG. 2A is a cross-sectional view of an example hybrid device; FIG. 2B is a cross-sectional view of an example LED package assembly; FIG. 2C is a top view of an example hybrid device; FIG. 3 is a flow chart of an example method of fabricating an LED package assembly; FIG. 4 is a cross-sectional view of an example substrate that may be used in the method of FIG. 3; FIG. 5 is a cross-sectional view of an example product manufactured by forming a recess in a substrate according to the method of FIG. 3; FIG. 6 is a cross-sectional view of an example product manufactured by forming holes in a substrate according to the method of FIG. 3; FIG. 7 is a cross-sectional view of an example product manufactured by positioning a hybrid device in a substrate according to the method of FIG. 3; FIG. 8 is a cross-sectional view of an example product manufactured according to the method of FIG. 3 coupling a hybrid device to a substrate via one or more flip-chip interconnects; FIG. 9 is a cross-sectional view of an example product fabricated by forming an underfill material around the flip-chip interconnects according to the method of FIG. 3; FIG. 10 is a cross-sectional view of an example product manufactured by coupling electronic components to a substrate according to the method of FIG. 3; FIG. 11 is a cross-sectional view of an example product manufactured by coupling a circuit board to a substrate according to the method of FIG. 3; FIG. 12 is a block diagram of an example system including an LED package assembly; FIG. 13 is a block diagram of another example system; FIG. 14 is a block diagram of an example lighting system, and Fig. 15 is an example hardware arrangement for implementing the system of fig. 13. Detailed Description Examples of different light illumination systems and/or light emitting diode ("LED") implementations are described more fully below with reference to the accompanying drawings. The examples are not mutually exclusive and features found in one example may be combined with features found in one or more other examples to implement further embodiments. Accordingly, it will be understood that the examples shown in the drawings are provided for illustrative purposes only and are not intended to limit the present 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 element. For example, a first element could be termed a second element and a second element could 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. It will be understood that when an element such as a layer, region or substrate is referred to as being "on" or "extending" another element, it can be directly on or extend directly onto the other element or intervening elements may also be present. In contrast, when an element is referred to as being "directly on" or "directly extending onto" another element, there may b