Organic electroluminescent display panel, preparation method thereof, and display device

1. An organic electroluminescent display panel comprising:

a base substrate,

a plurality of display components on a display area of the base substrate,

an etching layer between the base substrate and the plurality of display components, and

a thin film encapsulation structure covering the display area and a peripheral area of the base substrate;

wherein the etching layer comprises:

a convex with a narrow upper portion and a wide lower portion, a top surface of the convex being in the display area of the base substrate; and

a display component on an edge of the display area of the base substrate that extends beyond the convex; and

wherein the thin film encapsulation structure comprises at least one layer of inorganic film and at least one layer of organic film disposed alternatively, wherein the organic film only covers the plurality of display components, and the inorganic film covers the entire base substrate, but is broken at a tip of the display component extending beyond the convex.

2. The organic electroluminescent display panel according to claim 1 , wherein, in a direction perpendicular to the base substrate, a distance between the tip of the display component extending beyond the convex and a closest film layer on a side of the display component close to the base substrate is greater than a sum of thicknesses of all inorganic films.

3. The organic electroluminescent display panel according to claim 1 , wherein a shortest distance between the convex and an edge of the base substrate is not less than a distance between the tip of the display component extending beyond the convex and the edge of the base substrate.

4. The organic electroluminescent display panel according to claim 1 , wherein the etching layer further comprises a main body part covering the entire base substrate, and wherein the main body part is closer to the base substrate than the convex.

5. The organic electroluminescent display panel according to claim 4 , wherein the main body part and the convex are formed integrally.

6. The organic electroluminescent display panel according to claim 1 , further comprising: a thin film transistor between the base substrate and the plurality of display components, wherein an electrode in the display components is connected to the thin film transistor, and an insulating layer in the thin film transistor is also used as the etching layer.

7. The organic electroluminescent display panel according to claim 6 , wherein the thin film transistor comprises: an active layer, a gate electrode insulating layer, a gate electrode, an interlayer insulating layer, and source/drain electrodes sequentially disposed on the base substrate; wherein the interlayer insulating layer is also used as the etching layer.

8. The organic electroluminescent display panel according to claim 6 , wherein the thin film transistor comprises: an active layer, a gate electrode insulating layer, a gate electrode, an interlayer insulating layer, and source/drain electrodes sequentially disposed on the base substrate; wherein the interlayer insulating layer and the gate electrode insulating layer are also used as the etching layer.

9. The organic electroluminescent display panel according to claim 1 , wherein the plurality of display components comprise a flatten layer, and a pixel defining layer and a pixel unit on the flatten layer, wherein the pixel unit comprises an anode, a cathode and an organic electroluminescent unit between the anode and the cathode.

10. The organic electroluminescent display panel according to claim 9 , wherein the plurality of display components further comprise a post spacer layer on the pixel defining layer.

11. A display device comprising the organic electroluminescent display panel according to claim 1 .

12. A preparation method for the organic electroluminescent display panel according to claim 1 , comprising:

forming an etching film on the display area and the peripheral area of the base substrate;

forming the plurality of display components on the etching film in the display area of the base substrate, and after forming a flatten layer in the display components, dry etching the etching film to form an etching layer comprising a convex with a narrow upper portion and a wide lower portion, wherein a top surface of the convex is in the display area of the base substrate, and a display component on an edge of the display area of the base substrate extends beyond the convex; and

forming the thin film encapsulation structure on the display area and the peripheral area of the base substrate.

13. The preparation method according to claim 12 , wherein said dry etching the etching film to form the etching layer comprising the convex with the narrow upper portion and the wide lower portion comprises:

dry etching the etching film to form the etching layer comprising the convex with the narrow upper portion and the wide lower portion, such that in a direction perpendicular to the base substrate, a distance between the tip of the display component extending beyond the convex and a closest film layer on a side of the display component close to the base substrate is greater than a sum of thicknesses of all inorganic films.

14. The preparation method according to claim 12 , wherein, said dry etching the etching film to form the etching layer comprising the convex with the narrow upper portion and the wide lower portion comprises:

dry etching the etching film to form the etching layer comprising the convex with the narrow upper portion and the wide lower portion and a main body part covering the entire base substrate; wherein the main body part is closer to the base substrate than the convex, and the main body part and the convex are formed integrally.

15. The preparation method according to claim 12 , wherein, said after forming the flatten layer in the display components, dry etching the etching film to form the etching layer comprising the convex with the narrow upper portion and the wide lower portion comprises:

after forming a post spacer layer in the display components, dry etching the etching film with the post spacer layer as a mask to form the etching layer comprising the convex with the narrow upper portion and the wide lower portion.

16. The preparation method according to claim 12 , further comprising: forming a thin film transistor between the base substrate and the plurality of display components, wherein an electrode in the display components is connected to the thin film transistor, and an insulating layer in the thin film transistor is also used as the etching layer.

17. The preparation method according to claim 16 , wherein, the thin film transistor comprises: an active layer, a gate electrode insulating layer, a gate electrode, an interlayer insulating layer, and source/drain electrodes sequentially disposed on the base substrate; wherein the interlayer insulating layer is also used as the etching layer.

18. The preparation method according to claim 16 , wherein, the thin film transistor comprises: an active layer, a gate electrode insulating layer, a gate electrode, an interlayer insulating layer, and source/drain electrodes sequentially disposed on the base substrate; wherein the interlayer insulating layer and the gate electrode insulating layer are also used as the etching layer.

19. The preparation method according to claim 12 , wherein, process conditions for the dry etching comprises: power: 800 to 1500 W, pressure: 800 to 1200 mtorr, SF 6 : 30 to 260 sccm, Cl 2 : 10 to 80 sccm, He: 0 to 20 sccm, and duration: 200 to 700 s.

20. The preparation method according to claim 12 , wherein, said forming the thin film encapsulation structure on the display area and the peripheral area of the base substrate comprises:

forming an inorganic film on the entire base substrate, the inorganic film being broken at a tip of the display component extending beyond the convex; and

forming an organic layer covering the plurality of display components on the base substrate.