Quantum dot based color conversion layer in display devices
View Patent ↗Embodiments of a display device including barrier layer coated quantum dots and a method of making the barrier layer coated quantum dots are described. Each of the barrier layer coated quantum dots includes a core-shell structure and a hydrophobic barrier layer disposed on the core-shell structure. The hydrophobic barrier layer is configured to provide a distance between the core-shell structure of one of the quantum dots with the core-shell structures of other quantum dots that are in substantial contact with the one of the quantum dots. The method for making the barrier layer coated quantum dots includes forming reverse micro-micelles using surfactants and incorporating quantum dots into the reverse micro-micelles. The method further includes individually coating the incorporated quantum dots with a barrier layer and isolating the barrier layer coated quantum dots with the surfactants of the reverse micro-micelles disposed on the barrier layer.
1. A quantum dot film comprising:
barrier layer coated quantum dots, each of the barrier layer coated quantum dots including:
a quantum dot that comprises a core-shell structure having a core and a shell surrounding the core, and
an optically transparent barrier layer, disposed on the quantum dot, configured to provide a spacing between adjacent quantum dots to prevent aggregation of the adjacent quantum dots; and
a matrix material configured to house the barrier layer coated quantum dots and be in substantial contact with the optically transparent barrier layer,
wherein the barrier layer coated quantum dots exhibit a quantum yield greater than about 80%, wherein:
the core comprises a first material;
the shell comprises a second material;
the optically transparent barrier layer comprises a third material; and
the first, second, and third materials are different from each other; and
wherein the quantum dot film has a thickness in a range from about 70 μm to about 40 μm.
2. The quantum dot film of claim 1 , wherein the optically transparent barrier layer is hydrophobic.
3. The quantum dot film of claim 1 , wherein the spacing is equal or greater than a Forster radius between adjacent barrier layer coated quantum dots.
4. The quantum dot film of claim 1 , wherein the optically transparent barrier layer comprises an oxide.
5. The quantum dot film of claim 1 , wherein the optically transparent barrier layer comprises silicon oxide.
6. The quantum dot film of claim 1 , further comprising surfactants or ligands bonded to the optically transparent barrier layer.
7. The quantum dot film of claim 1 , wherein the quantum dot film exhibits an external quantum efficiency greater than about 50% after being treated at a temperature greater than 200° C.
8. The quantum dot film of claim 1 , wherein the quantum dot film comprises:
an optical density greater than about 0.24; and
an external quantum efficiency greater than about 50%.
9. The quantum dot film of claim 1 , wherein the barrier layer coated quantum dots have an average size ranging from about 20 nm to about 40 nm in diameter.
10. The quantum dot film of claim 1 , wherein the optically transparent barrier layer have a thickness ranging from about 8 nm to about 20 nm.
11. The quantum dot film of claim 1 , wherein the matrix material comprises an extrudable material.
12. The quantum dot film of claim 1 , wherein the matrix material comprises a brightness enhancement film.
13. The quantum dot film of claim 1 , wherein the matrix material comprises a polymer plastic film.
14. A quantum dot film comprising:
barrier layer coated quantum dots, each of the barrier layer coated quantum dots including:
a quantum dot, and
an optically transparent barrier layer, disposed on the quantum dot, configured to provide a spacing between adjacent quantum dots to prevent aggregation of the adjacent quantum dots; and
a matrix material configured to house the barrier layer coated quantum dots and be in substantial contact with the optically transparent barrier layer,
wherein the barrier layer coated quantum dots exhibit a quantum yield greater than about 80%,
wherein the quantum dot film exhibits an external quantum efficiency greater than about 50% after being treated at a temperature greater than 200° C.
15. The quantum dot film of claim 14 , wherein the optically transparent barrier layer is hydrophobic.
16. The quantum dot film of claim 14 , wherein the spacing is equal or greater than a Forster radius between adjacent barrier layer coated quantum dots.
17. The quantum dot film of claim 14 , wherein the quantum dot of each of the barrier layer coated quantum dots comprises a core-shell structure having a core and a shell surrounding the core.
18. The quantum dot film of claim 17 , wherein:
the core comprises a first material;
the shell comprises a second material;
the optically transparent barrier layer comprises a third material; and
the first, second, and third materials are different from each other.
19. The quantum dot film of claim 14 , wherein the optically transparent barrier layer comprises an oxide.
20. The quantum dot film of claim 14 , wherein the optically transparent barrier layer comprises silicon oxide.
21. The quantum dot film of claim 14 , further comprising surfactants or ligands bonded to the optically transparent barrier layer.
22. The quantum dot film of claim 14 , wherein the quantum dot film comprises:
an optical density greater than about 0.24; and
an external quantum efficiency greater than about 50%.
23. The quantum dot film of claim 14 , wherein the barrier layer coated quantum dots have an average size ranging from about 20 nm to about 40 nm in diameter.
24. The quantum dot film of claim 14 , wherein the optically transparent barrier layer have a thickness ranging from about 8 nm to about 20 nm.
25. The quantum dot film of claim 14 , wherein the matrix material comprises an extrudable material.
26. The quantum dot film of claim 14 , wherein the matrix material comprises a brightness enhancement film.
27. The quantum dot film of claim 14 , wherein the matrix material comprises a polymer plastic film.
28. The quantum dot film of claim 14 , has a thickness in a range from about 70 μm to about 40 μm.
29. A quantum dot film comprising:
barrier layer coated quantum dots, each of the barrier layer coated quantum dots including:
a quantum dot, and
an optically transparent barrier layer, disposed on the quantum dot, configured to provide a spacing between adjacent quantum dots to prevent aggregation of the adjacent quantum dots; and
a matrix material configured to house the barrier layer coated quantum dots and be in substantial contact with the optically transparent barrier layer,
wherein the barrier layer coated quantum dots exhibit a quantum yield greater than about 80%,
wherein the quantum dot film comprises:
an optical density greater than about 0.24; and
an external quantum efficiency greater than about 50%.
30. The quantum dot film of claim 29 , wherein the optically transparent barrier layer is hydrophobic.
31. The quantum dot film of claim 29 , wherein the spacing is equal or greater than a Forster radius between adjacent barrier layer coated quantum dots.
32. The quantum dot film of claim 29 , wherein the quantum dot of each of the barrier layer coated quantum dots comprises a core-shell structure having a core and a shell surrounding the core.
33. The quantum dot film of claim 32 , wherein:
the core comprises a first material;
the shell comprises a second material;
the optically transparent barrier layer comprises a third material; and
the first, second, and third materials are different from each other.
34. The quantum dot film of claim 29 , wherein the optically transparent barrier layer comprises an oxide.
35. The quantum dot film of claim 29 , wherein the optically transparent barrier layer comprises silicon oxide.
36. The quantum dot film of claim 29 , further comprising surfactants or ligands bonded to the optically transparent barrier layer.
37. The quantum dot film of claim 29 , wherein the barrier layer coated quantum dots have an average size ranging from about 20 nm to about 40 nm in diameter.
38. The quantum dot film of claim 29 , wherein the optically transparent barrier layer have a thickness ranging from about 8 nm to about 20 nm.
39. The quantum dot film of claim 29 , wherein the matrix material comprises an extrudable material.
40. The quantum dot film of claim 29 , wherein the matrix material comprises a brightness enhancement film.
41. The quantum dot film of claim 29 , wherein the matrix material comprises a polymer plastic film.
42. The quantum dot film of claim 29 , has a thickness in a range from about 70 μm to about 40 μm.