Organic photoelectric conversion element and imaging device

Patent metadata

Field	Value
Publication number	US-2015270315-A1
Application number	US-201414576441-A
Country	US
Kind code	A1
Filing date	Dec 19, 2014
Priority date	Mar 19, 2014
Publication date	Sep 24, 2015
Grant date	—

Abstract

According to one embodiment, an organic photoelectric conversion element has a positive electrode, a first charge transport layer, an organic photoelectric conversion, a second charge transport layer and a negative electrode, in this order. The first charge transport layer contains a first charge transport material having a LUMO level equal to or greater than that of the organic photoelectric conversion layer. The second charge transport layer contains a second charge transport material having a HOMO level equal to or less than that of the organic photoelectric conversion layer. The first charge transport layer contains an electron trapping/scattering material that has a HOMO level which is +0.5 eV or more, or −0.5 eV or less, than the HOMO level of the first charge transport material, and has a LUMO level which is between −0.5 eV to +0.5 eV of the LUMO level of the first electron transport material.

First claim

What is claimed is:

1 . An organic photoelectric conversion element comprising:
a positive electrode, a negative electrode, an organic photoelectric conversion layer provided between the positive electrode and the negative electrode, a first charge transport layer provided between the positive electrode and the organic photoelectric conversion layer, and the first charge transport layer comprising a first charge transport material that has a LUMO level equal to or greater than the LUMO level of the organic photoelectric conversion layer, and a second charge transport layer provided between the negative electrode and the organic photoelectric conversion layer, and the second charge transport layer comprising a second charge transport material that has a HOMO level equal to or less than the HOMO level of the organic photoelectric conversion layer, wherein, the first charge transport layer further contains an electron trapping/scattering material, wherein the electron trapping/scattering material has a HOMO level which is +0.5 eV or more, or −0.5 eV or less, than the HOMO level of the first charge transport material, and has a LUMO level which is between −0.5 eV to +0.5 eV of the LUMO level of the first electron transport material.

2 . An organic photoelectric conversion element comprising:
a positive electrode, a negative electrode, an organic photoelectric conversion layer provided between the positive electrode and the negative electrode, a first charge transport layer provided between the positive electrode and the organic photoelectric conversion layer, and the first charge transport layer comprising a first charge transport material that has a LUMO level equal to or greater than the LUMO level of the organic photoelectric conversion layer, and a second charge transport layer provided between the negative electrode and the organic photoelectric conversion layer, and the second charge transport layer comprising a second charge transport material which has a HOMO level equal to or less than a HOMO level of the organic photoelectric conversion layer, wherein, the second charge transport layer further contains a hole trapping/scattering material, wherein, the hole trapping/scattering material has a HOMO level which is between −0.5 eV to +0.5 eV of the HOMO level of the second charge transport material, and has a LUMO level which is +0.5 eV or more, or −0.5 eV or less, than the LUMO level of the second electron transport material.

3 . The organic photoelectric conversion element according to claim 1 , wherein the second charge transport layer further contains an electron trapping/scattering material, the hole trapping/scattering material has a HOMO level which is between −0.5 eV to +0.5 eV of the HOMO level of the second charge transport material, and has a LUMO level which is +0.5 eV or more, or −0.5 eV or less, than the LUMO level of the second charge transport material.

4 . The organic photoelectric conversion element according to claim 1 , wherein the electron trapping/scattering material is contained in the first charge transport layer at a weight ratio of 1% to 50%.

5 . The organic photoelectric conversion element according to claim 3 , wherein the electron trapping/scattering material is contained in the first charge transport layer at a weight ratio of 1% to 50%.

6 . The organic photoelectric conversion element according to claim 2 , wherein the hole trapping/scattering material is contained in the second charge transport layer at a weight ratio of 1% to 50%.

7 . The organic photoelectric conversion element according to claim 3 , wherein the hole trapping/scattering material is contained in the second charge transport layer at a weight ratio of 1% to 50%.

8 . The organic photoelectric conversion element according to claim 1 , wherein the energy level of the positive electrode is at least 1.3 eV lower than the LUMO level of the first charge transport material.

9 . The organic photoelectric conversion element according to claim 2 , wherein the energy level of the positive electrode is at least 1.3 eV lower than the LUMO level of the first charge transport material.

10 . The organic photoelectric conversion element according to claim 1 , wherein the energy level of the negative electrode is at least 1.3 eV higher than the HOMO level of the second charge transport material.

11 . The organic photoelectric conversion element according to claim 2 , wherein the energy level of the negative electrode is at least 1.3 eV higher than the HOMO level of the second charge transport material.

12 . The organic photoelectric conversion element according to claim 1 , wherein the LUMO level of the first charge transport material is higher than the LUMO level of the organic photoelectric conversion layer.

13 . The organic photoelectric conversion element according to claim 2 , wherein the LUMO level of the first charge transport material is higher than the LUMO level of the organic photoelectric conversion layer.

14 . The organic photoelectric conversion element according to claim 1 , wherein the HOMO level of the second charge transport material is lower than the HOMO level of the organic photoelectric conversion layer.

15 . The organic photoelectric conversion element according to claim 2 , wherein the HOMO level of the second charge transport material is lower than the HOMO level of the organic photoelectric conversion layer.

16 . An imaging device comprising the organic photoelectric conversion element according to claim 1 , wherein the photoelectric conversion element is included as photoelectric conversion elements, voltage application units that apply a voltage to each of the organic photoelectric conversion elements, and a signal processing unit that reads each of photoelectrically converted signals of the organic photoelectric conversion elements.

17 . An imaging device comprising the organic photoelectric conversion element according to claim 2 , wherein the photoelectric conversion element is included as photoelectric conversion elements, voltage application units that apply a voltage to each of the organic photoelectric conversion elements, and a signal processing unit that reads each of photoelectrically converted signals of the organic photoelectric conversion elements.

Assignees

• Toshiba Kk

Inventors

• Takasu Isao
• Wada Atsushi
• Nomura Yuko
• Ito Machiko

Classifications

• H10K30/50

  Photovoltaic [PV] devices · CPC title

• H01L27/307 Primary

  Electricity · mapped topic

• H01L51/424

  Electricity · mapped topic

• Y02E10/549

  Organic PV cells · CPC title

• H10K30/353 Primary

  comprising blocking layers, e.g. exciton blocking layers · CPC title