Display device and method of its manufacture

• US 7,235,920 B2
• Filed: 09/24/2003
• Issued: 06/26/2007
• Est. Priority Date: 02/24/2003
• Status: Active Grant

• Current Assignee: Pictiva Displays International Limited (f/k/a Dolya Holdco 5 Limited) (Key Patent Innovations Limited)
• Original Assignee: Osram Opto Semiconductors GmbH (Ams-Osram AG)
• Inventors: Hahn, Berthold, Haerle, Volker
• Primary Examiner(s): Patel; Ashok
• Application Number:
  US10/670,917
• Publication Number:
  US 20050073248A1
• Time in Patent Office: 1,371 Days
• Field of Search: 313498-512, 257/49, 257/59, 257/72, 257/77, 257/79, 257/103, 257/350, 257/613, 349/11
• US Class Current: 313/499
• CPC Class Codes: H01L 29/78684 having a semiconductor body comprising semiconductor materials of Group IV not being silicon, or alloys including an element of the group IV, e.g. Ge, SiN alloys, SiC alloys H01L29/7869 takes precedence
• CPC Class Codes: H10K 2102/3031 Two-side emission, e.g. transparent OLEDs [TOLED]
• CPC Class Codes: H10K 59/12 Active-matrix OLED [AMOLED] displays
• CPC Class Codes: H10K 59/32 Stacked devices having two or more layers, each emitting at different wavelengths
• CPC Class Codes: H10K 59/35 comprising red-green-blue [RGB] subpixels

Abstract

A display device and method for its manufacture. In a display device with a first array of individual display elements and a second array of control transistors for the display elements, control transistors are formed from a semiconductor material with a large band gap and are transparent in the visible spectral range. The invention also comprises a method for manufacturing such a display device.

Claims

1. A display device comprising:

a first array of individual display elements; and

a second array of control transistors for the display elements, wherein the control transistors include a semiconductor material with a band gap sufficiently large to be transparent in the visible spectral range and wherein the semiconductor material includes boron nitride.

2. The display device of claim 1, wherein the display elements include organic light-emitting elements.

3. The display device of claim 2, wherein the organic light-emitting elements include a layer sequence having a cathode, an electron transport layer, an organic light-emitting layer, a hole transport layer and an anode.

4. The display device of claim 1, wherein the display elements include liquid crystal elements.

5. The display device of claim 1, wherein the band gap of the semiconductor material of the control transistors is larger than 3 eV.

6. The display device of claim 1, wherein each control transistor controls several of the individual display elements.

7. The display device of claim 1, wherein the control transistors are formed in one or more thin layers of the semiconductor material.

8. The display device of claim 7, wherein a thin layer of the semiconductor material has a layer thickness in the range of approximately 0.5 μ

m to approximately 20 μ

m.

9. The display device of claim 1, wherein the array of display elements contains multiple sub-arrays, the display elements of each sub-array being designed and configured for showing various colors.

10. The display device of claim 9, wherein the array of display elements contains three sub-arrays, wherein the display elements of each sub-array is designed and configured for showing red, green and blue.

11. The display device of claim 9, wherein the multiple sub-arrays are disposed in the same plane on a carrier substrate.

12. The display device of claim 9, wherein the multiple sub-arrays are disposed in stacked layers in multiple planes.

13. The display device of claim 12, wherein each of the multiple sub-arrays is disposed on its own carrier substrate.

14. The display device of claim 13, wherein the carrier substrate is a glass plate.

15. The display device of claim 1, wherein each control transistor controls exactly one of the individual display elements.

16. A display device, comprising:

a first array of individual display elements; and

a second array of control transistors for the display elements, wherein the control transistors are formed from a semiconductor material with a band gap sufficiently large to be transparent in the visible spectral range, wherein the semiconductor material includes boron nitride.

17. A method of manufacturing a display device, comprising:

applying a layer of a semiconductor material having a band gap sufficiently large to be transparent in the visible spectral range to a transparent carrier, wherein the semiconductor material includes boron nitride;

processing the layer on the transparent carrier to provide a first array of control transistors; and

applying an amorphous light-emitting material to the control transistors to form a second array of individual display elements.

18. The method of claim 17, wherein the amorphous light-emitting material comprises an organic material for organic light emitting diodes.

19. The method of claim 17, wherein the transparent carrier is a glass carrier.

20. A method for manufacturing a display device, comprising:

processing a layer of a semiconductor material having a band gap sufficiently large to be transparent in the visible spectral range to provide a first array of control transistors, wherein the semiconductor material includes boron nitride;

applying the processed layer to a transparent carrier; and

applying an amorphous light-emitting material to the control transistors to form a second array of individual display elements.

21. The method of claim 20, wherein the amorphous light-emitting material comprises an organic material for organic light emitting diodes.

22. The method of claim 20, wherein the transparent carrier is a glass carrier.

23. The method of claim 20, further comprising:

producing the display elements for different colors with the corresponding control transistors, each display element being disposed on a transparent carrier; and

adjusting the transparent carriers with the display elements relative to one another.

24. The method of claim 23, wherein the transparent carrier is a glass carrier.

25. The method of claim 23, wherein the display elements are produced for red, green, and blue.

26. The method of claim 20, further comprising:

producing the display elements for different colors with corresponding control transistors, using planarizing technology to directly and vertically stack the elements on a shared transparent carrier.

27. The method of claim 26, wherein the transparent carrier is a glass carrier.

28. The method of claim 26, wherein the display elements are produced for red, green, and blue.