DISPLAY COMPRISING ULTRA-SMALL LEDS AND METHOD FOR MANUFACTURING SAME

• US 20160211245A1
• Filed: 07/08/2014
• Published: 07/21/2016
• Est. Priority Date: 07/09/2013
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: PSI Company Limited
• Inventors: Do, Young Rag
• Granted Patent: US 9,570,425 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: H01L 2224/32 of an individual layer connector
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2933/0025 relating to coatings
• CPC Class Codes: H01L 2933/0041 relating to wavelength conversion elements
• 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 33/505 characterised by the shape, e.g. plate or foil
• 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

Provided are a display including a nano-scale LED and a method for manufacturing the same. In detail, nano-scale LED devices, each of which has a nano unit, are connected to nano-scale electrodes without electrical short-circuit to overcome a limitation in which it is difficult to allow nano-scale LED devices according to the related art to stand up and be coupled to electrodes and a limitation in which it is difficult to allow the nano-scale LED devices to be one-to-one coupled to the nano-scale electrodes different from each other, thereby realizing a display including the nano-scale LEDs. Also, the display may have superior light extraction efficiency and prevent defective pixels and the defect of the whole display due to the defects of the nano-scale LED devices, which may rarely occur, from occurring to minimize the defects of the display including the nano-scale LEDs and maintain its original function.

Claims

1. A method for manufacturing a display comprising a nano-scale LED assembly, the method comprising:

(1) forming an electrode I on a substrate;

(2) forming an electrode II on the same plane as the electrode I or on the electrode I to form a plurality of electrode assembles comprising a first electrode connected to the electrode I and a second electrode spaced apart from the first electrode on the same plane as the first electrode and connected to the electrode II;

(3) injecting a solution containing a plurality of nano-scale LED devices onto a plurality of sub pixel sites formed on the plurality of electrode assembles; and

(4) applying power to the plurality of electrode assembles to form a plurality of sub pixels comprising the plurality of nano-scale LED devices connected to both of the first and second electrodes,

wherein each of the nano-scale LED devices comprises;

a first electrode layer, a first conductive type semiconductor layer formed on the first electrode layer;

an active layer formed on the first conductive type semiconductor layer;

a second conductive type semiconductor layer formed on the active layer; and

a second electrode layer formed on the second conductive type semiconductor layer,

the nano-scale LED device further comprises an insulation film, which covers an entire outer surface of a portion of at least the active layer to prevent an electrical short-circuit occurring due to contact between the active layer of the nano-scale LED device and the electrode assembly from occurring, on an outer surface thereof, and

a width X of the first electrode, a width Y of the second electrode, a distance Z between the first electrode and the second electrode adjacent to the first electrode, and a length H of the nano-scale LED device satisfy following relation expression 1.

0.5Z≦

H<

X+Y+2Z, where 100 nm<

X≦

10 μ

m, 100 nm<

Y≦

10 μ

m, and 100 nm<

Z≦

10 μ

m. 

 

[Relation Expression 1]

3. The method of claim 1, further comprising forming an insulation layer comprising the electrode I on the substrate between the step (1) and the step (2),

the nano-scale LED device in the step (3) has a length of about 100 nm to about 10 μ

m and an aspect ratio of about 1.2 to about 100, wherein the nano-scale LED device comprises a blue LED device,

the power in the step (4) has a voltage of about 0.1 V to about 1,000 V and a frequency of about 10 Hz to about 100 GHz, and the number of nano-scale LED devices provided per an area (100×

100 μ

m²) of the sub pixel site in the step (4) is about 2 to about 100,000, and

after the step (4), the method further comprises;

(5) forming a metal ohmic layer comprising connection portions between the first and second electrodes provided on the plurality of sub pixels and the nano-scale LED devices;

(6) forming a short-wave pass filter (SPDF) on an upper portion of each of the plurality of sub pixels comprising the metal ohmic layer;

(7) patterning a green color conversion layer on an upper portion of the short-wave pass filter (SPDF) corresponding to the selected sub pixels of the plurality of sub pixels and patterning a red color conversion layer on an upper portion of the short-wave pass filter (SPDF) corresponding to the selected sub pixels of the plurality of sub pixels; and

(8) forming a long-wave pass filter (LPDF) on upper portions of the green color conversion layer and the red color conversion layer.

4. The method of claim 1, further comprising forming an insulation barrier surrounding the plurality of sub pixel sites formed on the plurality of electrode assembles on the substrate in addition to the electrode assembly between the step (2) and the step (3).

2. A method for manufacturing a display comprising a nano-scale LED assembly, the method comprising:

(1) forming an electrode I on a substrate;

(2) forming an electrode II on the same plane as the electrode I or on the electrode I to form a plurality of electrode assembles comprising a first electrode connected to the electrode I and a second electrode spaced apart from the first electrode on the same plane as the first electrode and connected to the electrode II;

(3) independently injecting a first solution containing a plurality of blue nano-scale LED devices, a second solution containing a plurality of green nano-scale LED devices, and a third solution containing a plurality of red nano-scale LED devices onto a plurality of sub pixel sites formed on the plurality of electrode assembles; and

(4) applying power to the plurality of electrode assembles to form a plurality of sub pixels comprising the plurality of nano-scale LED devices connected to both of the first and second electrodes,

wherein each of the nano-scale LED devices comprises;

a first electrode layer, a first conductive type semiconductor layer formed on the first electrode layer;

an active layer formed on the first conductive type semiconductor layer;

a second conductive type semiconductor layer formed on the active layer; and

a second electrode layer formed on the second conductive type semiconductor layer,

the nano-scale LED device further comprises an insulation film, which covers an entire outer surface of a portion of at least the active layer to prevent an electrical short-circuit occurring due to contact between the active layer of the nano-scale LED device and the electrode assembly from occurring, on an outer surface thereof, and

a width X of the first electrode, a width Y of the second electrode, a distance Z between the first electrode and the second electrode adjacent to the first electrode, and a length H of the nano-scale LED device satisfy following relation expression 1.

0.5Z≦

H<

X+Y+2Z, where 100 nm<

X≦

10 μ

m, 100 nm<

Y≦

10 μ

m, and 100 nm<

Z≦

10 μ

m. 

 

[Relation Expression 1]

5. The method of claim 2, further comprising forming an insulation layer comprising the electrode I on the substrate between the step (1) and the step (2),

the nano-scale LED device in the step (3) has a length of about 100 nm to about 10 μ

m and an aspect ratio of about 1.2 to about 100, wherein the nano-scale LED device comprises a blue LED device,

the power in the step (4) has a voltage of about 0.1 V to about 1,000 V and a frequency of about 10 Hz to about 100 GHz, and the number of nano-scale LED devices provided per an area (100×

100 μ

m²) of the sub pixel site in the step (4) is about 2 to about 100,000, and

after the step (4), the method further comprises;

(5) forming a metal ohmic layer comprising connection portions between the first and second electrodes provided on the plurality of sub pixels and the nano-scale LED devices; and

(6) forming a passivation layer on an upper portion of each of the plurality of sub pixels comprising the metal ohmic layer.

6. The method of claim 2, further comprising forming an insulation barrier surrounding the plurality of sub pixel sites formed on the plurality of electrode assembles on the substrate in addition to the electrode assembles between the step (2) and the step (3).

7. A method for manufacturing a display comprising a nano-scale LED assembly, the method comprising:

(1) forming an electrode I on a substrate;

(2) forming an electrode II on the same plane as the electrode I or on the electrode I to form a plurality of electrode assembles comprising a first electrode connected to the electrode I and a second electrode spaced apart from the first electrode on the same plane as the first electrode and connected to the electrode II;

(3) injecting a plurality of nano-scale LED devices onto a plurality sub pixel sites formed on the plurality of electrode assembles; and

(4) injecting a solvent to the plurality of sup pixel sites and applying power to the plurality of electrode assembles to form a plurality of sub pixels comprising a plurality of nano-scale LED devices connected to both of the first and second electrodes;

wherein each of the nano-scale LED devices comprises;

a first electrode layer, a first conductive type semiconductor layer formed on the first electrode layer;

an active layer formed on the first conductive type semiconductor layer;

a second conductive type semiconductor layer formed on the active layer; and

a second electrode layer formed on the second conductive type semiconductor layer,

the nano-scale LED device further comprises an insulation film, which covers an entire outer surface of a portion of at least the active layer to prevent an electrical short-circuit occurring due to contact between the active layer of the nano-scale LED device and the electrode assembly from occurring, on an outer surface thereof, and

a width X of the first electrode, a width Y of the second electrode, a distance Z between the first electrode and the second electrode adjacent to the first electrode, and a length H of the nano-scale LED device satisfy following relation expression 1.

0.5Z≦

H<

X+Y+2Z, where 100 nm<

X≦

10 μ

m, 100 nm<

Y≦

10 μ

m, and 100 nm<

Z≦

10 μ

m. 

 

[Relation Expression 1]

8. A method for manufacturing a display comprising a nano-scale LED assembly, the method comprising:

(1) forming an electrode I on a substrate;

(2) forming an electrode II on the same plane as the electrode I or on the electrode I to form a plurality of electrode assembles comprising a first electrode connected to the electrode I and a second electrode spaced apart from the first electrode on the same plane as the first electrode and connected to the electrode II;

(3) independently injecting a plurality of blue nano-scale LED devices, a plurality of green nano-scale LED devices, and a plurality of red nano-scale LED devices onto a plurality of sub pixel sites formed on the plurality of electrode assembles; and

(4) injecting a solvent to the plurality of sup pixel sites and applying power to the plurality of electrode assembles to form a plurality of sub pixels comprising a plurality of nano-scale LED devices connected to both of the first and second electrodes;

wherein each of the nano-scale LED devices comprises;

a first electrode layer, a first conductive type semiconductor layer formed on the first electrode layer;

an active layer formed on the first conductive type semiconductor layer;

a second conductive type semiconductor layer formed on the active layer; and

a second electrode layer formed on the second conductive type semiconductor layer,

the nano-scale LED device further comprises an insulation film, which covers an entire outer surface of a portion of at least the active layer to prevent an electrical short-circuit occurring due to contact between the active layer of the nano-scale LED device and the electrode assembly from occurring, on an outer surface thereof, and

a width X of the first electrode, a width Y of the second electrode, a distance Z between the first electrode and the second electrode adjacent to the first electrode, and a length H of the nano-scale LED device satisfy following relation expression 1.

0.5Z≦

H<

X+Y+2Z, where 100 nm<

X≦

10 μ

m, 100 nm<

Y≦

10 μ

m, and 100 nm<

Z≦

10 μ

m. 

 

[Relation Expression 1]

9. A display comprising a nano-scale LED, the display comprising:

an electrode I disposed on a substrate;

an electrode II on the same plane as the electrode I or on the electrode I;

a plurality of electrode assembles comprising a first electrode connected to the electrode I and a second electrode spaced apart from the first electrode on the same plane as the first electrode and connected to the electrode II; and

a plurality of nano-scale LED devices connected both of to the first and second electrodes provided on a plurality of sub pixel sites disposed on the plurality of electrode assembles,

wherein each of the nano-scale LED devices comprises;

a first electrode layer, a first conductive type semiconductor layer formed on the first electrode layer;

an active layer formed on the first conductive type semiconductor layer;

a second conductive type semiconductor layer formed on the active layer; and

a second electrode layer formed on the second conductive type semiconductor layer,

the nano-scale LED device further comprises an insulation film, which covers an entire outer surface of a portion of at least the active layer to prevent an electrical short-circuit occurring due to contact between the active layer of the nano-scale LED device and the electrode assembly from occurring, on an outer surface thereof, and

a width X of the first electrode, a width Y of the second electrode, a distance Z between the first electrode and the second electrode adjacent to the first electrode, and a length H of the nano-scale LED device satisfy following relation expression 1.

0.5Z≦

H<

X+Y+2Z, where 100 nm<

X≦

10 μ

m, 100 nm<

Y≦

10 μ

m, and 100 nm<

Z≦

10 μ

m. 

 

[Relation Expression 1]

11. The display of claim 9, further comprising:

an insulation layer comprising the electrode I and disposed on the substrate and under the electrode II;

a metal ohmic layer comprising connection portions between the first and second electrodes disposed on a plurality of sub pixels and the nano-scale LED devices;

a short-wave pass filter (SPDF) disposed on an upper portion of each of the plurality of sub pixels comprising the metal ohmic layer;

a green color conversion layer patterned on an upper portion of the short-wave pass filter (SPDF) corresponding to the selected sub pixels of the plurality of sub pixels and a red color conversion layer patterned on an upper portion of the short-wave pass filter (SPDF) corresponding to the selected sub pixels of the plurality of sub pixels; and

a long-wave pass filter (LPDF) disposed on upper portions of the green color conversion layer and the red color conversion layer.

12. The display of claim 9, further comprising an insulation barrier surrounding each of the plurality of sub pixel sites and formed on the substrate in addition to the plurality of electrode assembles.

13. The display of claim 9, wherein the width X of the first electrode, the width Y of the second electrode, the distance Z between the first electrode and the second electrode adjacent to the first electrode, and the length H satisfy following relation expression 2.

Z≦

H≦

X+Y+Z, where 100 nm<

X≦

10 μ

m, 100 nm<

Y≦

10 μ

m, and 100 nm<

Z≦

10 μ

m. 

 

[Relation Expression 2]

14. The display of claim 9, wherein the electrodes I and II cross each other in a strip shape, the sub pixel sites are disposed in a space partitioned by the electrodes I and II, the number of nano-scale LED devices provided per an area (100×

100 μ

m²) of the sub pixel site is about 2 to about 100,000, the nano-scale LED device has a length of about 100 nm to about 10 μ

m and an aspect ratio of about 1.2 to about 100, and the nano-scale LED device comprises a blue LED device.

10. A display comprising a nano-scale LED, the display comprising:

an electrode I disposed on a substrate;

an electrode II on the same plane as the electrode I or on the electrode I;

a plurality of electrode assembles comprising a first electrode connected to the electrode I and a second electrode spaced apart from the first electrode on the same plane as the first electrode and connected to the electrode II; and

a plurality of nano-scale LED devices connected both of to the first and second electrodes provided on a plurality of sub pixel sites disposed on the plurality of electrode assembles,

wherein the nano-scale LED devices comprise;

a plurality of blue nano-scale LED devices, green nano-scale LED devices, and red nano-scale LED devices, wherein the nano-scale LED devices that emit light having one kind of color are disposed on each of the sub pixel sites,

each of the nano-scale LED device comprises;

a first electrode layer, a first conductive type semiconductor layer formed on the first electrode layer;

an active layer formed on the first conductive type semiconductor layer;

a second conductive type semiconductor layer formed on the active layer; and

a second electrode layer formed on the second conductive type semiconductor layer,

the nano-scale LED device further comprises an insulation film, which covers an entire outer surface of a portion of at least the active layer to prevent an electrical short-circuit occurring due to contact between the active layer of the nano-scale LED device and the electrode assembly from occurring, on an outer surface thereof, and

a width X of the first electrode, a width Y of the second electrode, a distance Z between the first electrode and the second electrode adjacent to the first electrode, and a length H of the nano-scale LED device satisfy following relation expression 1.

0.5Z≦

H<

X+Y+2Z, where 100 nm<

X≦

10 μ

m, 100 nm<

Y≦

10 μ

m, and 100 nm<

Z≦

10 μ

m. 

 

[Relation Expression 1]

15. The display of claim 10, further comprising an insulation barrier surrounding each of the plurality of sub pixel sites and disposed on the substrate in addition to the plurality of electrode assembles.