Organic light emitting display (OLED) and its method of manufacture

1 . An Organic Light Emitting Display (OLED) comprising:

a first electrode arranged on a substrate;

a Hole Transporting Layer (HTL) arranged on the first electrode;

a light Emitting Layer (EL) arranged on the HTL;

an Electron Transporting Layer (ETL) arranged on the light EL; and

a second electrode arranged on the ETL;

wherein the light EL includes a soluble hole transporting host, a soluble electron transporting host, and a soluble light emitting dopant;

wherein a difference of a Highest Occupied Molecular Orbital (HOMO) level between the HTL and the hole transporting host respectively and the light emitting dopant is 1 eV or less;

wherein a difference of a HOMO level between the HTL and the hole transporting host respectively and the electron transporting host is 0.5 eV or more;

wherein a difference of a Lowest Unoccupied Molecular Orbital (LUMO) level between the ETL and the electron transporting host respectively and the light emitting dopant is 1 eV or less; and

wherein a difference of a LUMO level between the ETL and the electron transporting host respectively and the hole transporting host is 0.5 eV or more.

2 . The OLED of claim 1 , wherein the light EL comprises a small molecule material.

3 . The OLED of claim 1 , wherein the HOMO level of the electron transporting host is lower than the HOMO level of the HTL by 0.5 eV or more.

4 . The OLED of claim 1 , wherein the LUMO level of the hole transporting host is higher than the LUMO level of the electron transporting layer by 0.5 eV or more.

5 . The OLED of claim 1 , wherein at least one of the electron transporting host and the ETL comprises a material selected from a group consisting of an anthracene compound, a phenanthracene compound, a pyrene compound, a perylene compound, a chrysene compound, a triphenylene compound, a fluoranthene compound, a periflanthene compound, an azole compound, a diazole compound, and a vinylene compound.

6 . The OLED of claim 1 , wherein at least one of the electron transporting host and the ETL comprises a material selected from a group consisting of TPBi, PBD, BCP, BAlq, and OXD7.

7 . The OLED of claim 1 , wherein the electron transporting host and the ETL comprise a same material.

8 . The OLED of claim 1 , wherein at least one of the hole transporting host and the HTL comprises a material selected from a group consisting of an oxadiazole compound having an amino substituent, a triphenylmethane compound having an amino substituent, a tertiary compound, a hydazone compound, a pyrazoline compound, an enamine compound, a styryl compound, a stilbene compound, and a carbazole compound.

9 . The OLED of claim 1 , wherein at least one of the hole transporting host and the HTL comprises a material selected from a group consisting of TBADN, NPB, TPD, Spiro-NPB, DMFL-NPB, DPFL-NPB, and mHOST5.

10 . The OLED of claim 1 , wherein the hole transporting host and the HTL comprise a same material.

11 . The OLED of claim 1 , wherein the HTL comprises a mixture film of PEDOT and PSS.

12 . The OLED of claim 1 , wherein the light EL further comprises a third soluble host to improve the characteristics of forming a thin film.

13 . The OLED of claim 12 , wherein the third soluble host comprises one of TPBi, TBADN, and mHOST5.

14 . The OLED of claim 1 , wherein the light emitting dopant comprises either an organic molecule or an organic-metal complex having either fluorescent or phosphorus characteristics.

15 . The OLED of claim 1 , wherein a content of the light emitting dopant in the light EL is in a range of 0.1 to 50 wt %.

16 . The OLED of claim 1 , wherein the light emitting dopant comprises one of Irpiq3 and BY4m.

17 . The OLED of claim 1 , wherein a ratio of a thickness of the light EL to a thickness of the ETL is in a range of from 1:100 to 100:1.

18 . The OLED of claim 1 , further comprising a Hole Injection Layer (HIL) arranged between the first electrode and the HTL.

19 . The OLED of claim 1 , further comprising an Electron Injection Layer (EIL) arranged between the ETL and the second electrode.

20 . The OLED of claim 19 , wherein the EIL comprises a LiF film.

21 . An Organic Light Emitting Display (OLED) comprising:

a first electrode arranged on a substrate;

a Hole Transporting Layer (HTL) arranged on the first electrode;

a light Emitting Layer (EL) arranged on the HTL; and

a second electrode arranged on the light EL;

wherein the light EL includes a soluble hole transporting host, a soluble electron transporting host, and a soluble light emitting dopant;

wherein a difference of a Highest Occupied Molecular Orbital (HOMO) level between the HTL and the hole transporting host respectively and the light emitting dopant is 1 eV or less;

wherein a difference of a HOMO level between the HTL and the hole transporting host respectively and the electron transporting host is 0 . 5 eV or more;

wherein a difference of a Lowest Unoccupied Molecular Orbital (LUMO) level between the electron transporting host and the light emitting dopant is 1 eV or less; and

wherein a difference of a LUMO level between the electron transporting host and the hole transporting host is 0.5 eV or more.

22 . A method of manufacturing an Organic Light Emitting Display (OLED), the method comprising:

forming a first electrode on a substrate;

forming a Hole Transporting Layer (HTL) on the first electrode;

forming a light Emitting Layer (EL) on the HTL using a solution process;

forming an Electron Transporting Layer (ETL) on the light EL; and

forming a second electrode on the ETL;

wherein forming the light EL includes forming a mixed solution containing a soluble hole transporting host, a soluble electron transporting host, and a soluble light emitting dopant;

wherein a difference of a Highest Occupied Molecular Orbital (HOMO) level between the HTL and the hole transporting host respectively and the light emitting dopant is 1 eV or less;

wherein a difference of a HOMO level between the HTL and the hole transporting host respectively and the electron transporting host is 0.5 eV or more;

wherein a difference of a Lowest Unoccupied Molecular Orbital (LUMO) level between the ETL and the electron transporting host respectively and the light emitting dopant is 1 eV or less; and

wherein a difference of a LUMO level between the ETL and the electron transporting host respectively and the hole transporting host is 0.5 eV or more.

23 . The method of claim 22 , wherein the light EL is formed of a small molecule material.

24 . The method of claim 22 , wherein the solution process is selected from a group consisting of spin coating, inkjet printing, gravure printing, roll to roll processing, syringe injection, dip coating, spray coating, relief printing, lithography printing, flexography printing, and screen printing.

25 . The method of claim 22 , wherein at least one of the electron transporting host and the ETL is formed of a material selected from a group consisting of an anthracene compound, a phenanthracene compound, a pyrene compound, a perylene compound, a chrysene compound, a triphenylene compound, a fluoranthene compound, a periflanthene compound, an azole compound, a diazole compound, and a vinylene compound.

26 . The method of claim 22 , wherein at least one of the electron transporting host and the ETL is formed of a material selected from a group consisting of TPBi, PBD, BCP, BAlq, and OXD7.

27 . The method of claim 22 , wherein at least one of the hole transporting host and the HTL is formed of a material selected from a group consisting of an oxadiazole compound having an amino substituent, a triphenylmethane compound having an amino substituent, a tertiary compound, a hydazone compound, a pyrazoline compound, an enamine compound, a styryl compound, a stilbene compound, and a carbazole compound.

28 . The method of claim 22 , wherein at least one of the hole transporting host and the HTL is formed of a material selected from a group consisting of TBADN, NPB, TPD, Spiro-NPB, DMFL-NPB, DPFL-NPB, and mHOST5.

29 . The method of claim 22 , wherein the light EL further comprises a third soluble host to improve the characteristics of forming a thin film.

30 . The method of claim 29 , wherein the third soluble host comprises one of TPBi, TBADN, and mHOST5.

31 . The method of claim 22 , wherein the HTL is formed of a mixture film of PEDOT and PSS.

32 . The method of claim 22 , wherein the light emitting dopant is either an organic molecule or an organic-metal complex having either fluorescent or phosphorus characteristics.

33 . The method of claim 22 , wherein the light emitting dopant is one of Irpiq3 and BY4m.

34 . A method of manufacturing an Organic Light Emitting Display (OLED), the method comprising:

forming a first electrode on a substrate;

forming a Hole Transporting Layer (HTL) on the first electrode;

forming a light Emitting Layer (EL) on the HTL using a solution process; and

forming a second electrode on the light EL;

wherein forming the light EL includes forming a mixed solution containing a soluble hole transporting host, a soluble electron transporting host, and a soluble light emitting dopant;

wherein a difference of a Highest Occupied Molecular Orbital (HOMO) level between the HTL and the hole transporting host respectively and the light emitting dopant is 1 eV or less;

wherein a difference of a HOMO level between the HTL and the hole transporting host respectively and the electron transporting host is 0.5 eV or more;

wherein a difference of a Lowest Unoccupied Molecular Orbital (LUMO) level between the electron transporting host and the light emitting dopant is 1 eV or less; and

wherein a difference of a LUMO level between the electron transporting host and the hole transporting host is 0.5 eV or more.