Methods for manufacturing a display device

• US 10,121,710 B2
• Filed: 01/19/2017
• Issued: 11/06/2018
• Est. Priority Date: 06/14/2016
• Status: Active Grant

• Current Assignee: InnoLux Corporation
• Original Assignee: InnoLux Corporation
• Inventors: Chang, Chia-Hsiung, Hung, Ting-Kai, Lin, Hsiao-Lang
• Primary Examiner(s): Blum, David S
• Application Number:
  US15/409,809
• Publication Number:
  US 20170358505A1
• Time in Patent Office: 656 Days
• Field of Search: 438 10
• CPC Class Codes: H01L 22/22 Connection or disconnection of sub-entities or redundant parts of a device in response to a measurement testing and repair of stores after manufacture including at wafer scale G11C29/00; fuses per se H01L23/525
• CPC Class Codes: H01L 25/167 comprising optoelectronic devices, e.g. LED, photodiodes
• 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 27/1214 comprising a plurality of TFTs formed on a non-semiconducting substrate, e.g. driving circuits for AMLCDs
• CPC Class Codes: H01L 2933/0041 relating to wavelength conversion elements
• CPC Class Codes: H01L 2933/005 relating to encapsulations
• CPC Class Codes: H01L 2933/0066 relating to arrangements for conducting electric current to or from the semiconductor body
• CPC Class Codes: H01L 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating
• CPC Class Codes: H01L 33/50 Wavelength conversion elements
• CPC Class Codes: H01L 33/52 Encapsulations
• 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

Abstract

Methods for manufacturing a display device are provided. A representative method includes: providing a thin film transistor (TFT) substrate having a plurality of sub-pixel locations and a plurality of TFTs corresponding to the plurality of sub-pixel locations; providing a carrier substrate supporting a plurality of light emitting diodes (LEDs), wherein each of the plurality of LEDs has a first electrical contact and a second electrical contact; transferring the plurality of LEDs from the carrier substrate to the TFT substrate, with at least two of the plurality of LEDs being disposed at one of the plurality of sub-pixel locations; and fixing positions of the plurality of LEDs with respect to the TFT substrate. The method also may include: determining that a first LED of the plurality of LEDs is defective; and electrically isolating the first electrical contact of first LED from a first electrode of the display device.

Claims

1. A method for manufacturing a display device comprising:

providing a thin film transistor (TFT) substrate having a plurality of sub-pixel locations and a plurality of TFTs corresponding to the plurality of sub-pixel locations, wherein a first electrode is disposed at one of the plurality of sub-pixel locations;

providing a carrier substrate supporting a plurality of light emitting diodes (LEDs), wherein each of the plurality of LEDs has a first electrical contact and a second electrical contact;

transferring the plurality of LEDs from the carrier substrate to the TFT substrate, with at least two of the plurality of LEDs being disposed at the one of the plurality of sub-pixel locations;

fixing positions of the plurality of LEDs with respect to the TFT substrate;

determining that one of the at least two of the plurality of LEDs at the one of the plurality of sub-pixel locations is defective; and

laser cutting the first electrode disposed at the one of the plurality of sub-pixel locations.

2. The method of claim 1, further comprising:

providing a filling insulator at the one of the plurality of sub-pixel locations, wherein the filling insulator fills between the at least two of the plurality of LEDs disposed at the one of the plurality of sub-pixel locations.

3. The method of claim 2, further comprising:

electrically isolating the one of the at least two of the plurality of LEDs determined to be defective.

4. The method of claim 3, wherein the electrically isolating comprises providing a passivation layer over the first electrical contact of the one of the at least two of the plurality of LEDs determined to be defective.

5. The method of claim 3, further comprising forming a first electrode over the plurality of LEDs.

6. The method of claim 5, wherein the one of the plurality of LEDs determined to be defective is not covered by the first electrode.

7. The method of claim 6, further comprising providing at least one of a color filter and a wavelength conversion layer over the first electrode layer.

8. The method of claim 1, wherein:

in providing the TFT substrate, the one of sub-pixel locations has a corresponding reflective structure; and

in transferring the plurality of LEDs from the carrier substrate to the TFT substrate, the at least two of the plurality of LEDs are disposed over the corresponding reflective structure at the one of the plurality of sub-pixel locations.

9. The method of claim 8, wherein:

in providing the TFT substrate, an insulating layer is provided;

after the fixing positions of the plurality of LEDs, the plurality of LEDs exhibit a maximum elevation with respect to the TFT substrate; and

a top surface of the insulating layer is positioned to be lower than the maximum elevation.

10. The method of claim 9, wherein:

the insulating layer is provided at a thickness (t) extending between a bottom surface of the insulating layer and a top surface of the insulating layer; and

a distance (d) between the top surface of the insulating layer and the maximum elevation is between approximately 3% of the thickness and approximately 70% of the thickness.

11. A method for manufacturing a display device comprising:

providing a thin film transistor (TFT) substrate having a plurality of sub-pixel locations and a plurality of TFTs;

providing a carrier substrate supporting a plurality of light emitting diodes (LEDs), wherein each of the plurality of LEDs has a first electrical contact and a second electrical contact;

transferring the plurality of LEDs from the carrier substrate to the TFT substrate, with a corresponding one of the plurality of LEDs being disposed at each of the plurality of sub-pixel locations;

fixing positions of the plurality of LEDs with respect to the TFT substrate;

providing a filling insulator contacting sidewalls of the plurality of LEDs;

determining that a first LED of the plurality of LEDs is defective; and

electrically isolating the first electrical contact of the first LED determined to be defective, wherein electrically isolating the first electrical contact comprises laser cutting a first electrode of the display device.

12. The method of claim 11, wherein the first electrode of the display device is not disposed over the first LED determined to be defective.

13. The method of claim 11, wherein, in transferring the plurality of LEDs, at least two of the plurality of LEDs are disposed at each of the plurality of sub-pixel locations.

14. The method of claim 11, wherein:

in providing the TFT substrate, an insulating layer is provided;

after the fixing positions of the plurality of LEDs, the plurality of LEDs exhibit a maximum elevation with respect to the TFT substrate; and

a top surface of the insulating layer is positioned to be lower than the maximum elevation.

15. The method of claim 14, wherein:

the insulating layer is provided at a thickness (t) extending between a bottom surface of the insulating layer and a top surface of the insulating layer; and

a distance (d) between the top surface of the insulating layer and the maximum elevation is between approximately 3% of the thickness and approximately 70% of the thickness.