MICRO ASSEMBLED LED DISPLAYS AND LIGHTING ELEMENTS

• US 20160343772A1
• Filed: 08/02/2016
• Published: 11/24/2016
• Est. Priority Date: 06/18/2014
• Status: Active Grant

• Current Assignee: X Display Company Technology Limited (Sensinnovat BVBA)
• Original Assignee: X-Celeprint Limited
• Inventors: Bower, Christopher, Meitl, Matthew, Gomez, David, Bonafede, Salvatore, Kneeburg, David, Fecioru, Alin, Prevatte, Carl
• Granted Patent: US 9,705,042 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: F21V 9/08 for producing coloured light, e.g. monochromatic; for reducing intensity of light with provision for controlling the colour F21V9/40
• CPC Class Codes: F21Y 2105/10 comprising a two-dimensional array of point-like light-generating elements
• CPC Class Codes: F21Y 2113/13 comprising an assembly of point-like light sources
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G02B 26/04 by periodically varying the intensity of light, e.g. using choppers shutters, diaphragms for cameras G03B9/00; devices for eliminating or reducing the effect of flicker in projection systems G03B21/40
• CPC Class Codes: G02F 1/167 by electrophoresis
• CPC Class Codes: G09G 2300/0452 Details of colour pixel setup, e.g. pixel composed of a red, a blue and two green components
• CPC Class Codes: G09G 2300/0842 forming a memory circuit, e.g. a dynamic memory with one capacitor
• CPC Class Codes: G09G 2310/0264 Details of driving circuits
• CPC Class Codes: G09G 3/22 using controlled light sources
• CPC Class Codes: G09G 3/32 semiconductive, e.g. using light-emitting diodes [LED]
• CPC Class Codes: H01L 2224/18 High density interconnect [HDI] connectors; Manufacturing methods related thereto
• CPC Class Codes: H01L 2224/73267 Layer and HDI connectors
• CPC Class Codes: H01L 2224/92244 the second connecting process involving a build-up interconnect
• CPC Class Codes: H01L 23/4821 Bridge structure with air gap
• CPC Class Codes: H01L 23/5381 Crossover interconnections, e.g. bridge stepovers
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 25/167 comprising optoelectronic devices, e.g. LED, photodiodes
• CPC Class Codes: H01L 27/156 two-dimensional arrays
• CPC Class Codes: H01L 33/20 with a particular shape, e.g. curved or truncated substrate
• CPC Class Codes: H01L 33/36 : characterised by the electrodes
• CPC Class Codes: H01L 33/38 : with a particular shape
• CPC Class Codes: H01L 33/385 : the electrode extending at least partially onto a side surface of the semiconductor body
• CPC Class Codes: H01L 33/405 : Reflective materials
• CPC Class Codes: H01L 33/48 : characterised by the semiconductor body packages
• CPC Class Codes: H01L 33/50 : Wavelength conversion elements
• CPC Class Codes: H01L 33/502 : Wavelength conversion materials
• CPC Class Codes: H01L 33/508 : having a non-uniform spatial arrangement or non-uniform concentration, e.g. patterned wavelength conversion layer, wavelength conversion layer with a concentration gradient of the wavelength conversion material
• CPC Class Codes: H01L 33/58 : Optical field-shaping elements
• CPC Class Codes: H01L 33/60 : Reflective elements
• CPC Class Codes: H01L 33/62 : Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls
• CPC Class Codes: H05K 1/0306 : Inorganic insulating substrates, e.g. ceramic, glass
• CPC Class Codes: H05K 1/09 : Use of materials for the conductive, e.g. metallic pattern
• CPC Class Codes: H05K 1/181 : associated with surface mounted components
• CPC Class Codes: H05K 1/182 : associated with components mounted in the printed circuit board, e.g. insert mounted components [IMC]
• CPC Class Codes: H05K 2201/0329 : Intrinsically conductive polymer [ICP]; Semiconductive polymer
• CPC Class Codes: H05K 2201/10106 : Light emitting diode [LED]
• CPC Class Codes: H05K 2201/10128 : Display
• CPC Class Codes: H05K 2201/10166 : Transistor
• CPC Class Codes: H05K 5/0017 : with operator interface units

Abstract

The disclosed technology provides micro-assembled micro-LED displays and lighting elements using arrays of micro-LEDs that are too small (e.g., micro-LEDs with a width or diameter of 10 μm to 50 μm), numerous, or fragile to assemble by conventional means. The disclosed technology provides for micro-LED displays and lighting elements assembled using micro-transfer printing technology. The micro-LEDs can be prepared on a native substrate and printed to a display substrate (e.g., plastic, metal, glass, or other materials), thereby obviating the manufacture of the micro-LEDs on the display substrate. In certain embodiments, the display substrate is transparent and/or flexible.

Claims

1. An inorganic light-emitting diode display, the display comprising:

a plurality of inorganic light-emitting diodes assembled in an array on a display substrate non-native to the plurality of light-emitting diodes, wherein;

each light-emitting diode of the array comprises a first metal terminal on a first side of the corresponding light-emitting diode horizontally separated from a second metal terminal on the first side of the same light-emitting diode by a horizontal distance;

the horizontal distance is from 100 nm to 20 microns;

the first side of the LED comprises one or more surfaces;

a patterned transparent non-emissive dielectric layer covers at least a portion of all of the surfaces of the first side of each light-emitting diode;

the patterned transparent non-emissive dielectric layer, the first metal terminal, or the second metal terminal cover all of the surfaces of the first side of the LED;

the patterned transparent non-emissive dielectric layer is absent from a second side of the LED opposite the first side; and

for each inorganic light-emitting diode of the plurality of inorganic light-emitting diodes, a surface of the first metal terminal and a surface of a second metal terminal share a plane.

2. The display of claim 1, wherein the display substrate has a thickness from 5 to 10 microns, 10 to 50 microns, 50 to 100 microns, 100 to 200 microns, 200 to 500 microns, 500 microns to 0.5 mm, 0.5 to 1 mm, 1 mm to 5 mm, 5 mm to 10 mm, or 10 mm to 20 mm.

3. The display of claim 1, wherein each of the plurality of light-emitting diodes has a width from 2 to 5 μ

m, 5 to 10 μ

m, 10 to 20 μ

m, or 20 to 50 μ

m.

4. The display of claim 1, wherein each of the plurality of light-emitting diodes has a length from 2 to 5 μ

m, 5 to 10 μ

m, 10 to 20 μ

m, or 20 to 50 μ

m.

5. The display of claim 1, wherein each of the plurality of light-emitting diodes has with a height from 2 to 5 μ

m, 4 to 10 μ

m, 10 to 20 μ

m, or 20 to 50 μ

m.

7. The display of claim 1, wherein each light-emitting diode comprises:

a conduction layer;

an inorganic light-emitting layer disposed on a portion of the conduction layer, the conduction layer comprising a cantilever extension extending beyond an edge of the inorganic light-emitting layer, wherein the first metal terminal is disposed on a portion of the inorganic light-emitting layer and the second metal terminal is disposed on the cantilever extension of the conduction layer, wherein a current supplied between the first metal terminal and the second metal terminal causes the inorganic light-emitting layer to emit light.

12. The display of claim 1, wherein the display is a downward emitting micro-LED display such that a majority of light emitted by the plurality of light-emitting diodes is emitted through the display substrate.

13. The display of claim 12, comprising a plurality of optical reflection structures, each optical reflection structure located on a same side of a corresponding light-emitting diode of the plurality of light-emitting diodes as the first metal terminal.

16. The display of claim 1, wherein the display is an upward emitting micro-LED display such that a majority of light emitted by the plurality of light-emitting diodes is emitted in a direction away from the display substrate.

17. The display of claim 16, comprising a plurality of optical reflection structures, each optical reflection structure located underneath a corresponding light-emitting diode of the plurality of light-emitting diodes on an opposite side of said light-emitting diode from the first metal terminal.

18. The display of claim 17, wherein the first and second metal terminals are at least partially transparent, thereby allowing light emitted from a respective light-emitting diode to at least partially pass through the first and second metal terminals.

6. (canceled)

8-11. -11. (canceled)

14-15. -15. (canceled)

19-31. -31. (canceled)

32. An inorganic light-emitting diode display, the display comprising:

a plurality of inorganic light-emitting diodes assembled in an array on a display substrate non-native to the plurality of light-emitting diodes, wherein;

each light-emitting diode of the array comprises a first metal terminal on a first side of the corresponding light-emitting diode horizontally separated from a second metal terminal on the first side of the same light-emitting diode by a horizontal distance,

the horizontal distance is from 100 nm to 20 microns,

the first side of the LED comprises one or more surfaces,

a patterned transparent non-emissive dielectric layer covers at least a portion of all of the surfaces of the first side of each light-emitting diode,

the patterned transparent non-emissive dielectric layer, the first metal terminal, or the second metal terminal cover all of the surfaces of the first side of the LED, and

the patterned transparent non-emissive dielectric layer is absent from a second side of the LED opposite the first side; and

a plurality of micro integrated circuits on the display substrate, each electrically connected with a set of the plurality of light-emitting diodes.

33. The display of claim 32, wherein each integrated circuit is used to control LEDs that emit a certain color of light.

34. The display of claim 32, wherein each set of the plurality of light-emitting diodes driven by a respective integrated circuit forms an independent sub-display.

35. An inorganic light-emitting diode display, the display comprising:

a plurality of inorganic light-emitting diodes assembled in an array on a display substrate non-native to the plurality of light-emitting diodes, wherein;

each light-emitting diode of the array comprises a first metal terminal on a first side of the corresponding light-emitting diode horizontally separated from a second metal terminal on the first side of the same light-emitting diode by a horizontal distance,

the horizontal distance is from 100 nm to 20 microns,

the first side of the LED comprises one or more surfaces,

a patterned transparent non-emissive dielectric layer covers at least a portion of all of the surfaces of the first side of each light-emitting diode,

the patterned transparent non-emissive dielectric layer, the first metal terminal, or the second metal terminal cover all of the surfaces of the first side of the LED, and

the patterned transparent non-emissive dielectric layer is absent from a second side of the LED opposite the first side; and

a plurality of second inorganic light-emitting diodes assembled in a second array on a second display substrate non-native to the plurality of second light-emitting diodes, wherein each second light-emitting diode of the plurality of second light-emitting diodes comprises a first metal terminal on a first side of the corresponding light-emitting diode horizontally separated from a second metal terminal on the first side of the same light-emitting diode by a horizontal distance, wherein the horizontal distance is from 100 nm to 20 microns, wherein the first display substrate and the second substrate are stacked.

76. The display of claim 35, wherein the array of the plurality of inorganic light-emitting diodes has a different resolution than the second array of the plurality of second inorganic light-emitting diodes.

77. The display of claim 35, wherein each of the plurality of inorganic light-emitting diodes has a first size, each of the plurality of second inorganic light-emitting diodes has a second size, and the first size is different than the second size.

36. An inorganic light-emitting diode display, the display comprising:

a plurality of inorganic light-emitting diodes assembled in an array on a display substrate non-native to the plurality of light-emitting diodes, wherein;

each light-emitting diode of the array comprises a first metal terminal on a first side of the corresponding light-emitting diode horizontally separated from a second metal terminal on the first side of the same light-emitting diode by a horizontal distance,

the horizontal distance is from 100 nm to 20 microns,

the first side of the LED comprises one or more surfaces,

a patterned transparent non-emissive dielectric layer covers at least a portion of all of the surfaces of the first side of each light-emitting diode,

the patterned transparent non-emissive dielectric layer, the first metal terminal, or the second metal terminal cover all of the surfaces of the first side of the LED, and

the patterned transparent non-emissive dielectric layer is absent from a second side of the LED opposite the first side; and

a plurality of second inorganic light-emitting diodes assembled in a second array on a side of the display substrate opposite the plurality of inorganic light-emitting diodes, wherein each second light-emitting diode of the plurality of second light-emitting diode comprises a first metal terminal on a first side of the corresponding light-emitting diode horizontally separated from a second metal terminal on the first side of the same light-emitting diode by a horizontal distance, wherein the horizontal distance is from 100 nm to 20 microns, wherein the first display substrate and the second substrate are stacked.

37. The display of claim 36, wherein the array of the plurality of inorganic light-emitting diodes has a different resolution than the second array of the plurality of second inorganic light-emitting diodes.

38. The display of claim 36, wherein each of the plurality of inorganic light-emitting diodes has a first size, each of the plurality of second inorganic light-emitting diodes has a second size, and the first size is different than the second size.

39-75. -75. (canceled)