Organic electroluminescence device and a method for producing the device
An organic electroluminescence device includes: an anode; a cathode opposed to the anode; and a plurality of emitting units including at least a first emitting unit and a second emitting unit. The plurality of emitting units each includes: an emitting layer; and an intermediate unit between the first emitting unit and the second emitting unit. The intermediate unit includes an electron injecting layer, a zinc oxide layer and a hole injecting layer in this sequence from the anode. The electron injecting layer contains an electron donating material and is adjacent to the first emitting unit. The hole injecting layer contains an organic electron accepting material and is adjacent to the second emitting unit.
1. An organic electroluminescence device comprising:
an anode;
a cathode opposed to the anode;
a plurality of emitting units provided between the anode and the cathode and comprising at least a first emitting unit and a second emitting unit, the plurality of emitting units each comprising an emitting layer; and
an intermediate unit between the first emitting unit and the second emitting unit, wherein
the intermediate unit comprises an electron injecting layer, a zinc-containing complex oxide layer and a hole injecting layer in this sequence from the anode;
a zinc-containing complex oxide contained in the zinc-containing complex oxide layer comprises zinc and an metal element M except for zinc;
the zinc-containing complex oxide is represented by a formula (1) below,
ZnM x O y (1)
where: x is an integer of 1 or 2 and y is an integer of 2 to 6, and the metal element M is selected from the group consisting of Mo, W, Ti, Al, Zr, and V.
2. The organic electroluminescence device according to claim 1 , wherein
the electron injecting layer comprises an electron donating material and is adjacent to the first emitting unit, and
the hole injecting layer comprises an organic electron accepting material and is adjacent to the second emitting unit.
3. The organic electroluminescence device according to claim 2 , wherein
the organic electron accepting material is an organic compound comprising an electron accepting group.
4. The organic electroluminescence device according to claim 2 , wherein
the electron donating material is any one of an alkali metal, an alkali metal compound and an organic electron donating material.
5. The organic electroluminescence device according to claim 4 , wherein
the electron injecting layer comprises an electron transporting material and at least any one of the alkali metal, the alkali metal compound and the organic electron donating material.
6. The organic electroluminescence device according to claim 1 , wherein
the first emitting unit comprises an electron transporting layer, the electron transporting layer being adjacent to the electron injecting layer and being formed of one or more organic compounds.
7. The organic electroluminescence device according to claim 1 , wherein
the emitting layer in the first emitting unit is adjacent to the electron injecting layer and is formed of one or more organic compounds.
8. The organic electroluminescence device according to claim 1 , wherein
a thickness of the zinc-containing complex oxide layer is in a range from 3 nm to 20 nm.
9. The organic electroluminescence device according to claim 1 , wherein
the zinc-containing complex oxide layer and the hole injecting layer are connected to each other.
10. The organic electroluminescence device according to claim 1 , wherein
the hole injection layer comprises an organic electron accepting material being represented by a formula (2) below,
where R 1 , R 2 , R 3 , R 4 , R 5 , and R 6 independently represents a substituent selected from the group consisting of:
hydrogen;
halogen;
a hydroxyl group;
an amino group;
arylamino group;
a substituted or unsubstituted carbonyl group having 20 or less carbon atoms;
a substituted or unsubstituted carbonyl ester group having 20 or less carbon atoms;
a substituted or unsubstituted alkyl group having 20 or less carbon atoms;
a substituted or unsubstituted alkenyl group having 20 or less carbon atoms;
a substituted or unsubstituted alkoxyl group having 20 or less carbon atoms;
a substituted or unsubstituted aryl group having 30 or less carbon atoms;
a substituted or unsubstituted helerocyclic group having 30 or less carbon atoms;
a nitrile group;
a nitro;
a cyano group; and
a silyl group,
adjacent ones of R 1 , R 2 , R 3 , R 4 , R 5 , and R 6 may be bonded to each other through a cyclic structure, and
X 1 , X 2 , X 3 , X 4 , X 5 , and X 6 are independently a carbon atom or a nitrogen atom.
11. The organic electroluminescence device according to claim 1 ,
wherein
the hole injecting layer comprises an organic electron accepting material being represented by a formula (3) below,
where Ar 1 is an organic group that can be substituted by a halogen or CN group, the organic group being selected from the group consisting of organic groups listed below,
where A 3 is independently an oxygen atom, a sulfur atom, or a selenium atom and A 4 is independently a sulfur atom or a selenium atom.
12. The organic electroluminescence device according to claim 1 ,
wherein
the hole injecting layer comprises an organic electron accepting material being represented by a formula (4) below,
wherein A 5 is independently a carbon atom, a sulfur atom, a selenium atom, a tellurium atom or an oxygen atom, and M is a nickel atom, a palladium atom, a platinum atom, or a zinc atom.
13. The organic electroluminescence device according to claim 1 ,
wherein
the hole injecting layer comprises an organic electron accepting material being represented by a formula (5) below,
where A 5 is independently a carbon atom, a sulfur atom, a selenium atom or tellurium atom, and M is a nickel atom, a palladium atom, a platinum atom, or a zinc atom.
14. The organic electroluminescence device according to claim 1
wherein
the hole injecting layer comprises an organic electron accepting material being represented by a formula (6) below,
wherein R 4 is independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 50 carbon atoms or an alkoxyl group having 1 to 50 carbon atoms.
15. The organic electroluminescence device according to claim 1
wherein
the hole injecting layer comprised an organic electron accepting material being represented by a formula (I) below,
where Ar 1 is a fused ring having 6 to 24 carbon atoms forming the ring or a heterocyclinc ring having 6 to 24 atoms foring the ring and ar 1 and ar 2 may be the same of different from each other, ar 1 and ar 2 being represented by a formula (i) or (ii) below,
where X 1 and X 2 may be the same or different from each other, X 1 and X 2 being one of divalent groups represented by formulae (a) to (g) below,
where R 21 , R 22 , R 23 and R 24 may be the same or different from each other, R 21 , R 22 , R 23 and R 24 representing:
a hydrogen atom;
a fluoroalkyl group;
a substituted or unsubstituted alkyl group;
a substituted or unsubstituted alkyl group; or
a substituted or unsubstituted heterocyclic group, wherein R 22 and R 23 may be bonded to each other to form a ring,
where R 1 , R 2 , R 3 and R 4 in the formula (I) may be the same or different from each other, R 1 , R 2 , R 3 and R 4 representing:
a hydrogen atom;
a substituted or unsubstituted alkyl group;
a substituted or unsubstituted aryl group; or
a substituted or unsubstituted heterocyclic group;
a halogen atom;
a substituted or unsubstituted fluoralkyl group;
an aryloxy; or
a cyano group, wherein adjacent ones of R 1 , R 2 , R 3 and R 4 may be bonded to each other to form a ring,
where Y 1 , Y 2 , Y 3 and Y 4 and in the formula (I) may be the same of different from each other, each of Y 1 , Y 2 , Y 3 and Y 4 being one of —N—, —CH═ or —C(R 5 )═, and
where R 5 represents:
a substituted or unsubstituted alkyl group;
a substituted or unsubstituted aryl group; or
a substituted or unsubstituted heterocyclic group;
a halogen atom;
a fluoralkyl group;
an alkoxyl group;
an aryloxy group; or
a cyano group.