MICRO-TRANSFER PRINTED LED AND COLOR FILTER STRUCTURES

• US 20180277525A1
• Filed: 05/25/2018
• Published: 09/27/2018
• Est. Priority Date: 04/05/2016
• Status: Active Grant

• Current Assignee: X Display Company Technology Limited (Sensinnovat BVBA)
• Original Assignee: X-Celeprint Limited
• Inventors: Cok, Ronald S., Bower, Christopher Andrew
• Granted Patent: US 10,692,844 B2
• Time in Patent Office: Days
• CPC Class Codes: H01L 24/00 Arrangements for connecting or disconnecting semiconductor or solid-state bodies; Methods or apparatus related thereto
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 25/50 Multistep manufacturing processes of assemblies consisting of devices, each device being of a type provided for in group H01L27/00 or H01L29/00 H01L21/50 takes precedence
• CPC Class Codes: H01L 2933/0025 relating to coatings
• CPC Class Codes: H01L 2933/0041 relating to wavelength conversion elements
• CPC Class Codes: H01L 33/0095 Post-treatment of devices, e.g. annealing, recrystallisation or short-circuit elimination
• CPC Class Codes: H01L 33/502 Wavelength conversion materials
• CPC Class Codes: H01L 33/505 characterised by the shape, e.g. plate or foil

Abstract

A micro-transfer printed intermediate structure comprises an intermediate substrate and one or more pixel structures disposed on the intermediate substrate. Each pixel structure includes an LED, a color filter, and a fractured pixel tether physically attached to the pixel structure. A fractured intermediate tether is physically attached to the intermediate substrate. A method of making an intermediate structure source wafer comprises providing a source wafer having a patterned sacrificial layer including sacrificial portions separated by anchors, disposing an intermediate substrate over the patterned sacrificial layer, and disposing one or more pixel structures on the intermediate substrate entirely on or over each sacrificial portion. Each pixel structure includes an LED, a color filter, and a fractured pixel tether physically attached to the pixel structure to form an intermediate structure.

Claims

1. A micro-transfer printed color-filter structure, comprising:

a color filter; and

a fractured color-filter tether attached to the color filter or layers formed in contact with the color filter.

2. The color filter of claim 1, wherein the color filter is or includes one or more of:

a curable resin, a dye, a pigment, a color-conversion material, a semiconductor crystal, a phosphor, and a quantum dot.

3. The color filter of claim 1, wherein the fractured color-filter tether includes at least some of the same material as the color filter or further comprising an encapsulation layer and wherein the fractured color-filter tether includes at least some of the same material as the encapsulation layer or at least a portion of the encapsulation layer forms the color-filter tether.

4-10. -10. (canceled)

11. A micro-transfer printed pixel structure, comprising:

an LED having a light-emitting side;

a color filter disposed adjacent to the light-emitting side of the LED; and

a fractured pixel tether physically attached to the LED or layers disposed on or in contact with the LED, or a fractured pixel tether physically attached to the color filter or layers disposed on the color filter.

12. The pixel structure of claim 11, wherein the color filter is or includes one or more of:

a curable resin, a dye, a pigment, a color conversion material, a semiconductor crystal, a phosphor, and a quantum dot.

13. The pixel structure of claim 11, wherein the fractured pixel tether includes at least some of the same material as the color filter, wherein the fractured pixel tether includes at least some of the same material as the LED, or both, or comprising an encapsulation layer encapsulating the LED and color filter that forms the fractured pixel tether or the fractured pixel tether is a part of or is attached to the encapsulation layer.

14-20. -20. (canceled)

21. A micro-transfer printed intermediate structure, comprising:

an intermediate substrate;

one or more pixel structures disposed on or over the intermediate substrate, each pixel structure including an LED having a light-emitting side, a color filter disposed adjacent to the light-emitting side of the LED, and a fractured pixel tether physically attached to the pixel structure; and

a fractured intermediate tether physically attached to the intermediate substrate or physically attached to a layer disposed on the intermediate substrate.

22. The intermediate structure of claim 21, wherein:

(i) the color filter is or includes one or more of;

a curable resin, a dye, a pigment, a color conversion material, a semiconductor crystal, a phosphor, or a quantum dot;

(ii) the intermediate substrate is or includes a glass, a polymer, a semiconductor, or silicon;

or

any one or any combination of (i), and (ii).

23. The intermediate structure of claim 21, wherein the fractured pixel tether includes at least some of the same material as the color filter or wherein the fractured pixel tether includes at least some of the same material as the LED, or both, or comprising an encapsulation layer encapsulating the color filter and LED and wherein the pixel tether includes at least some of the same material as the encapsulation layer or at least a portion of the encapsulation layer forms the pixel tether or the pixel tether is a part of or is attached to the encapsulation layer.

24. The intermediate structure of claim 21, wherein the fractured intermediate tether includes at least some of the same material as the color filter or wherein the fractured intermediate tether includes at least some of the same material as the intermediate substrate, or both, or comprising an encapsulation layer encapsulating the color filter and LED and wherein the intermediate tether includes at least some of the same material as the encapsulation layer or at least a portion of the encapsulation layer forms the intermediate tether or the intermediate tether is a part of or is attached to the encapsulation layer.

25-33. -33. (canceled)

34. An LED display, comprising:

a display substrate; and

a plurality of pixel structures disposed on the display substrate, each pixel structure including one or more LEDs, each LED having a light-emitting side, and a color filter corresponding to each LED, each color filter disposed adjacent to the light-emitting side of the corresponding LED.

35. The LED display of claim 34, wherein each color filter is located between the display substrate and an LED.

36. The LED display of claim 34, wherein each LED is located between the display substrate and a color filter.

37. The LED display of claim 34, wherein each LED is a micro-transfer printed LED and a fractured LED tether is physically attached to the LED.

38. The LED display of claim 34, wherein each color filter is a micro-transfer printed color filter and a fractured color-filter tether is physically attached to the color filter.

39. The LED display of claim 34, wherein each pixel structure is a micro-transfer printed pixel structure having a fractured pixel tether.

40. The LED display of claim 34, wherein each pixel structure is part of an intermediate structure having a fractured intermediate tether.

41. A method of making an LED display, comprising:

providing a display substrate; and

disposing a plurality of pixel structures on the display substrate, each pixel structure including one or more LEDs, each LED having a light-emitting side, and a color filter corresponding to each LED, each color filter disposed adjacent to the light-emitting side of the corresponding LED.

42. The method of claim 41, wherein each LED is a micro-transfer printed LED having a fractured LED tether physically attached to the LED or layers on, over, or in contact with the LED.

43. The method of claim 42, comprising disposing a pixel structure on the display substrate by:

(i) micro-transfer printing a color filter from a color-filter source wafer onto the display substrate and micro-transfer printing an LED from an LED source wafer onto the color filter so that the color filter is disposed adjacent to the light-emitting side of the LED;

(ii) micro-transfer printing an LED from an LED source wafer onto the display substrate and micro-transfer printing a color filter from a color-filter source wafer onto the LED so that the color filter is disposed adjacent to the light-emitting side of the LED;

(iii) micro-transfer printing an LED from an LED source wafer onto the display substrate and forming a color filter over the LED so that the color filter is disposed adjacent to the light-emitting side of the LED;

(iv) forming a color filter on the display substrate and micro-transfer printing an LED from an LED source wafer onto the color filter so that the color filter is disposed adjacent to the light-emitting side of the LED;

(v) micro-transfer printing a pixel structure from a pixel structure source wafer onto the intermediate substrate of the source wafer entirely over the sacrificial portion;

or

(vi) micro-transfer printing an intermediate structure from an intermediate structure source wafer onto the display substrate.