Micro-LED array transfer
Methods of transferring micro-array LEDs of various colors onto a surface of a display substrate are provided. The transferring includes releasing micro-LEDs of a specific color from a structure that includes a releasable material onto a display substrate. The releasable material may be a laser ablatable material or a material that is readily dissolved in a specific etchant.
1. A method of forming a structure, the method comprising:
providing, in any order, a first structure containing a plurality of adhesive structures on a surface of a release layer that is located on a handler substrate, and a second structure containing a first set of LEDs on a temporary support substrate, wherein said plurality of adhesive structures is formed by forming a photo-patternable adhesive layer on the release layer, and patterning the photo-patternable adhesive layer, wherein the patterning includes exposing the photo-patternable adhesive layer to a pattern of radiation and developing the exposed photo-patternable adhesive layer;
first transferring a preselected number of LEDs of the first set of LEDs to the first structure by adhering a physically exposed surface of each adhesive structure to the release layer; and
second transferring the preselected number of LEDs of the first set of LEDs from the first structure to a surface of a display substrate, wherein the second transferring includes contacting a physically exposed surface of each of the preselected number of LEDs of the first set of LEDs to the surface of the display substrate and removing the release layer.
2. The method of claim 1 , wherein the release layer is a laser ablatable material, and the removing the release layer comprises laser ablation.
3. The method of claim 1 , wherein the release layer is an etchant dissolvable material, and the removing comprises contacting the release layer with an etchant.
4. The method of claim 1 , wherein the second transferring also transfers each adhesive structure that is located on the preselected number of LEDs of the first set of LEDs, and wherein each adhesive structure is removed after the second transferring.
5. The method of claim 1 , wherein each LED of the first set of LEDs emits a first color.
6. The method of claim 5 , further comprising providing a second set of LEDs that emit a second color that is different from the first color and a third set of LEDs that emit a third color that is different from both the first color and the second color to the display substrate.
7. The method of claim 6 , wherein the providing the second set of LEDs comprises:
providing, in any order, another first structure containing a plurality of adhesive structures on a surface of a release layer that is located on a handler substrate, and another second structure containing the second set of LEDs on a temporary support substrate;
first transferring a preselected number of LEDs of the second set of LEDs to the another first structure by adhering a physically exposed surface of each adhesive structure to the release layer; and
second transferring the preselected number of LEDs of the second set of LEDs from the another first structure to the display substrate, wherein the second transferring includes contacting a physically exposed surface of each of the preselected number of LEDs of the second set of LEDs to the surface of the display substrate and removing the release layer.
8. The method of claim 7 , wherein the providing the third set of LEDs comprises:
providing, in any order, yet another first structure containing a plurality of adhesive structures on a surface of a release layer that is located on a handler substrate, and yet another second structure containing the third set of LEDs on a temporary support substrate;
first transferring a preselected number of LEDs of the third set of LEDs to the yet another first structure by adhering a physically exposed surface of each adhesive structure to the release layer; and
second transferring the preselected number of LEDs of the third set of LEDs from the yet another first structure to the display substrate, wherein the second transferring includes contacting a physically exposed surface of each of the preselected number of LEDs of the third set of LEDs to the surface of the display substrate and removing the release layer.
9. A method of providing a structure, the method comprising:
providing, in any order, a first structure containing a release layer that is located on a handler substrate, and a second structure containing a first set of LEDs on a temporary support substrate, wherein an adhesive structure is located on a surface of a preselected number of the LEDs of the first set of LEDs, and said adhesive structure is formed by forming a photo-patternable adhesive layer laterally surrounding and located above each LED of the first set of LEDs, and patterning the photo-patternable adhesive layer, wherein the patterning includes exposing the photo-patternable adhesive layer to a pattern of radiation and developing the exposed photo-patternable adhesive layer;
first transferring the preselected number of LEDs of the first set of LEDs to the release layer of the first structure by adhering a physically exposed surface of each adhesive structure to the release layer; and
second transferring the preselected number of LEDs of the first set of LEDs from the first structure to a surface of a display substrate, wherein the second transferring includes contacting a physically exposed surface of each of the preselected number of LEDs of the first set of LEDs to the surface of the display substrate and removing the release layer.
10. The method of claim 9 , wherein the release layer is a laser ablatable material, and the removing the release layer comprises laser ablation.
11. The method of claim 9 , wherein the release layer is an etchant dissolvable material, and the removing comprises contacting the release layer with an etchant.
12. The method of claim 9 , wherein the second transferring also transfers each adhesive structure that is located on the preselected number of LEDs of the first set of LEDs, and wherein each adhesive structure is removed after the second transferring.
13. The method of claim 9 , wherein each LED of the first set of LEDs emits a first color.
14. The method of claim 13 , further comprising providing a second set of LEDs that emit a second color that is different from the first color and a third set of LEDs that emit a third color that is different from both the first color and the second color to the display substrate.
15. The method of claim 14 , wherein the providing the second set of LEDs comprises providing, in any order, another first structure containing a release layer that is located on a handler substrate, and another second structure containing the second set of LEDs on a temporary support substrate, wherein an adhesive structure is located on a surface of a preselected number of the LEDs of the second set of LEDs;
first transferring the preselected number of LEDs of the second set of LEDs to the release layer of the another first structure by adhering a physically exposed surface of each adhesive structure to the release layer; and
second transferring the preselected number of LEDs of the second set of LEDs from the another first structure to the display substrate, wherein the second transferring includes contacting a physically exposed surface of each of the preselected number of LEDs of the second set of LEDs to the surface of the display substrate and removing the release layer.
16. The method of claim 15 , wherein the providing the third set of LEDs comprises
providing, in any order, a yet another first structure containing a release layer that is located on a handler substrate, and yet another second structure containing the third set of LEDs on a temporary support substrate, wherein an adhesive structure is located on a surface of a preselected number of the LEDs of the third set of LEDs;
first transferring the preselected number of LEDs of the third set of LEDs to the release layer of the yet another first structure by adhering a physically exposed surface of each adhesive structure to the release layer; and
second transferring the preselected number of LEDs of the third set of LEDs from the yet another first structure to the display substrate, wherein the second transferring includes contacting a physically exposed surface of each of the preselected number of LEDs of the third set of LEDs to the surface of the display substrate and removing the release layer.