Methods of forming organic light emitting structures and methods of manufacturing organic light emitting display devices

1. A method of forming an organic light emitting structure, comprising the steps of:

forming a plurality of first electrodes spaced apart from each other on a lower substrate;

forming a first organic layer covering the first electrodes on the lower substrate;

forming a preliminary pixel defining layer on the first organic layer, the preliminary pixel defining layer including a photosensitive material;

selectively exposing the preliminary pixel defining layer to light so that the preliminary pixel defining layer and a portion of the first organic layer beneath the preliminary pixel defining layer are transformed into a pixel defining layer and a first organic layer pattern, respectively;

forming an emitting layer on the first organic layer exposed by the pixel defining layer;

forming a second organic layer on the emitting layer; and

forming a second electrode on the second organic layer.

2. The method of claim 1 ,

wherein a remaining portion of the first organic layer, except for the first organic layer pattern, is defined as a second organic layer pattern; and

wherein the first organic layer pattern has hole transport capability or hole injection capability less than those of the second organic layer pattern.

3. The method of claim 1 , wherein the preliminary pixel defining layer further includes a photoinitiator.

4. The method of claim 3 , wherein the first organic layer pattern is formed by active species that are generated by the photoinitiator and diffused to the first organic layer.

5. The method of claim 4 , wherein the first organic layer pattern includes a polymer cross-linked or polymerized by the active species.

6. The method of claim 1 ,

wherein the photosensitive material of the preliminary pixel defining layer is cured or hardened to form the pixel defining layer; and

wherein the pixel defining layer has a surface energy less than those of the preliminary pixel defining layer, the first organic layer, the emitting layer and the second organic layer.

7. A method of forming an organic light emitting structure, comprising the steps of:

forming a plurality of first electrodes spaced apart from each other on a lower substrate;

forming a hole transport layer covering the first electrodes on the lower substrate;

forming a preliminary pixel defining layer on the hole transport layer, the preliminary pixel defining layer including a photosensitive material;

selectively exposing the preliminary pixel defining layer to light so that the preliminary pixel defining layer and a portion of the hole transport layer beneath the preliminary pixel defining layer are transformed into a pixel defining layer and a first hole transport layer pattern, respectively;

forming an emitting layer on the hole transport layer exposed by the pixel defining layer;

forming an electron transport layer on the emitting layer; and

forming a second electrode on the electron transport layer.

8. The method of claim 7 ,

wherein a remaining portion of the hole transport layer, except for the first hole transport layer pattern, is defined as a second hole transport layer pattern; and

wherein the first hole transport layer pattern has a hole transport capability or an electrical conductivity less than those of the second hole transport layer pattern.

9. The method of claim 7 , wherein at least one of the preliminary pixel defining layer and the hole transport layer includes a photoinitiator.

10. The method of claim 9 ,

wherein the hole transport layer includes a hole transport material and a photosensitive monomer; and

wherein the first hole transport layer pattern includes a polymer produced by a cross-linking reaction of the photosensitive monomer or a polymerization reaction of the photosensitive monomer, the cross-linking reaction or the polymerization reaction being induced by active species generated by the photoinitiator.

11. The method of claim 9 , further comprising the step of forming a hole injection layer before forming the hole transport layer;

wherein a portion of the hole injection layer beneath the first hole transport layer pattern is transformed into a first hole injection layer pattern.

12. The method of claim 11 ,

wherein the hole injection layer includes a hole injection material and a photosensitive monomer; and

wherein the first hole injection layer pattern includes a polymer produced by a cross-linking reaction of the photosensitive monomer or a polymerization reaction of the photosensitive monomer, the cross-linking reaction or the polymerization reaction being induced by active species generated by the photoinitiator.

13. The method of claim 12 ,

wherein a remaining portion of the hole injection layer, except for the first injection layer pattern, is defined as a second injection layer pattern; and

wherein the first hole injection layer pattern has a hole injection capability or an electrical conductivity less than those of the second injection layer pattern.

14. The method of claim 11 ,

wherein the hole injection layer includes a hole injection material and a photoinitiator; and

wherein the first hole injection layer pattern includes active species generated by the photoinitiator.

15. A method of manufacturing an organic light emitting display device, comprising the steps of:

forming a lower structure on a lower substrate, the lower structure including a switching device and an insulation layer;

forming a first electrode electrically connected to the switching device on the lower structure;

forming a first organic layer covering the first electrode on the lower structure;

forming a preliminary pixel defining layer on the first organic layer, the preliminary pixel defining layer including a photosensitive material;

selectively exposing the preliminary pixel defining layer to light so that the preliminary pixel defining layer and a portion of the first organic layer beneath the preliminary pixel defining layer are transformed into a pixel defining layer and a first organic layer pattern, respectively;

forming an emitting layer on the first organic layer exposed by the pixel defining layer;

forming a second organic layer on the emitting layer; and

forming a second electrode on the second organic layer.

16. The method of claim 15 , wherein at least one of the preliminary pixel defining layer and the first organic layer includes a photoinitiator.

17. The method of claim 16 ,

wherein the first organic layer includes a hole transport material and a photosensitive monomer; and

wherein the first organic layer pattern includes a polymer produced by a cross-linking reaction of the photosensitive monomer or a polymerization reaction of the photosensitive monomer, the cross-linking reaction or the polymerization reaction being induced by active species generated by the photoinitiator.

18. The method of claim 17 ,

wherein a remaining portion of the first organic layer, except for the first organic layer pattern, is defined as a second organic layer pattern; and

wherein the first organic layer pattern has a hole transport capability or an electrical conductivity less than those of the second organic layer pattern.

19. The method of claim 15 ,

wherein the second organic layer includes an electron transport layer; and

wherein the electron transport layer is formed on the emitting layer and a sidewall of the pixel defining layer, and the electron transport layer is not formed on a top surface of the pixel defining layer.

20. The method of claim 15 , wherein the second organic layer includes an electron transport layer; and

wherein the electron transport layer covers the pixel defining layer and the emitting layer.

21. The method of claim 15 , wherein the switching device includes one of a thin film transistor and an oxide semiconductor device.

22. The method of claim 15 ,

wherein the photosensitive material of the preliminary pixel defining layer is cured or hardened to form the pixel defining layer; and

wherein the pixel defining layer has a surface energy less than those of the preliminary pixel defining layer, the first organic layer, the emitting layer and the second organic layer.

23. The method of claim 1 ,

wherein the second organic layer includes an electron transport layer; and

wherein the electron transport layer is formed on the emitting layer and a sidewall of the pixel defining layer, and the electron transport layer is not formed on a top surface of the pixel defining layer.

24. The method of claim 7 ,

wherein the second organic layer includes an electron transport layer; and

wherein the electron transport layer is formed on the emitting layer and a sidewall of the pixel defining layer, and the electron transport layer is not formed on a top surface of the pixel defining layer.