Organic photosensitive optoelectronic device with an exciton blocking layer

• US 6,451,415 B1
• Filed: 11/26/1999
• Issued: 09/17/2002
• Est. Priority Date: 08/19/1998
• Status: Expired due to Term

• Current Assignee: The Trustees of Princeton University (Princeton University)
• Original Assignee: The Trustees of Princeton University (Princeton University)
• Inventors: Forrest, Stephen R., Bulovic, Vladimir, Peumans, Peter
• Primary Examiner(s): YAMNITZKY, MARIE ROSE
• Application Number:
  US09/449,801
• Time in Patent Office: 1,026 Days
• Field of Search: 136/243, 136/252, 136/263, 428/212, 428/913, 313/523, 257/184, 257/185, 257/461, 252/501.1
• US Class Current: 428/212
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: H10K 2102/103 comprising indium oxides, e.g. ITO
• CPC Class Codes: H10K 30/211 comprising multiple junctions, e.g. double heterojunctions
• CPC Class Codes: H10K 30/353 comprising blocking layers, e.g. exciton blocking layers
• CPC Class Codes: H10K 30/57 comprising multiple junctions, e.g. tandem PV cells
• CPC Class Codes: H10K 39/30 Devices controlled by radiation
• CPC Class Codes: H10K 39/32 Organic image sensors
• CPC Class Codes: H10K 85/1135 Polyethylene dioxythiophene [PEDOT]; Derivatives thereof
• CPC Class Codes: H10K 85/311 Phthalocyanine
• CPC Class Codes: H10K 85/60 Organic compounds having low molecular weight H10K85/10 - H10K85/50 take precedence
• CPC Class Codes: H10K 85/621 Aromatic anhydride or imide compounds, e.g. perylene tetra-carboxylic dianhydride or perylene tetracarboxylic di-imide
• CPC Class Codes: H10K 85/657 Polycyclic condensed heteroaromatic hydrocarbons
• CPC Class Codes: H10K 85/6572 comprising only nitrogen in the heteroaromatic polycondensed ring system, e.g. phenanthroline or carbazole
• CPC Class Codes: Y02E 10/549 Organic PV cells
• CPC Class Codes: Y10S 428/913 Material designed to be responsive to temperature, light, moisture
• CPC Class Codes: Y10T 428/24942 including components having same physical characteristic in differing degree

Abstract

Organic photosensitive optoelectronic devices (“OPODs”) which include an exciton blocking layer to enhance device efficiency. Single heterostructure, stacked and wave-guide type embodiments. Photodetector OPODs having multilayer structures and an exciton blocking layer. Guidelines for selection of exciton blocking layers are provided.

Claims

1. An organic photosensitive optoelectronic device comprising:

two electrodes in superposed relation;

a hole transport layer between the two electrodes, the hole transport layer formed of a first photoconductive organic semiconductor material;

an electron transport layer between the two electrodes and adjacent to the hole transport layer, the electron transport layer formed of a second photoconductive organic semiconductor material; and

at least one exciton blocking layer between the two electrodes and adjacent to at least one of the two electrodes.

2. The device of claim 1 wherein one exciton blocking layer is between the electron transport layer and the electrode adjacent the exciton blocking layer.

3. The device of claim 1 wherein one exciton blocking layer is between the hole transport layer and the electrode adjacent the exciton blocking layer.

4. The device of claim 1 wherein the at least one exciton blocking layer is a first exciton blocking layer and a second exciton blocking layer, the first exciton blocking layer being between the electron transport layer and the electrode adjacent the first exciton blocking layer, the second exciton blocking layer being between the hole transport layer and the electrode adjacent the second exciton blocking layer.

5. The device of claim 1 wherein the first photoconductive organic semiconductor material and the second photoconductive organic semiconductor material are selected to have spectral sensitivity in the visible spectrum.

6. The device of claim 2 wherein:

the electron transport layer is 3,4,9, 10-perylenetetracarboxylic-bis-benzimidazole (PTCBI);

the hole transport layer is copper phthalocyanine (CuPc); and

the exciton blocking layer is 2,9-dimethyl-4,7-diphenyl-1, 10-phenanthroline (BCP).

7. The device of claim 3 wherein:

the electron transport layer is 3,4,9, 10-perylenetetracarboxylic-bis-benzimidazole (PTCBI);

the hole transport layer is copper phthalocyanine (CuPc); and

the exciton blocking layer is selected from the group consisting of 4,4′

,4″

-tris {N,-(3-methylphenyl)-N-phenylamino}triphenylamine (m-MTDATA) and polyethylene dioxythiophene (PEDOT).

8. The device of claim 1 wherein the electron transport layer, the hole transport layer, and the at least one exciton blocking layer are disposed between two parallel planar reflective surfaces which form a waveguide.

9. The device of claim 8 wherein one of the two reflective surfaces has an aperture to admit light incident upon the device.

10. The device of claim 8 having a transparent opening between the two reflective surfaces so that light is admitted to the device from a direction parallel to the planes of the reflective surfaces.

11. A stacked organic photosensitive optoelectronic device comprised of a plurality of photosensitive optoelectronic subcells wherein at least one subcell comprises:

two electrodes in superposed relation;

a hole transport layer between the two electrodes, the hole transport layer formed of a first photoconductive organic semiconductor material;

an electron transport layer between the two electrodes and adjacent to the hole transport layer, the electron transport layer formed of a second photoconductive organic semiconductor material; and

at least one exciton blocking layer between the two electrodes and adjacent to at least one of the two electrodes.

12. The device of claim 11 wherein the electron transport layer includes 3,4,9, 10-perylenetetracarboxylic-bis-benzimidazole (PTCBI) and the hole transport layer includes copper phthalocyanine (CuPc).

13. The device of claim 11 wherein the at least one exciton blocking layer includes 2.9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) and is between the electron transport layer and the electrode adjacent the at least one exciton blocking layer.

14. The device of claim 11 wherein the at least one exciton blocking layer is selected from the group consisting of 4,4′

,4″

-tris{N,-(3-methylphenyl)-N-phenylamino}triphenylamine (m-MTDATA) and polyethylene dioxythiophene (PEDOT), and is between the hole transport layer and the electrode adjacent the at least one exciton blocking layer.

15. An organic photodetector comprising:

a cathode and an anode in superposed relation;

a plurality of pairs of a hole transporting layer adjacent to an electron transporting layer, the pairs disposed between the cathode and the anode; and

an exciton blocking layer disposed between one of the cathode and the anode, and the plurality of pairs.

16. The photodetector of claim 15 wherein the exciton blocking layer is disposed between the anode and the plurality of pairs.

17. The photodetector of claim 15 wherein the exciton blocking layer is disposed between the cathode and the plurality of pairs.

18. The photodetector of claim 15 wherein the exciton blocking layer comprises 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP).

19. The photodetector of claim 15 wherein the exciton blocking layer is selected from the group consisting of 4,4′

,4″

-tris{N,-(3-methylphenyl)-N-phenylamino}triphenylamine (m-MTDATA) and polyethylene.

20. The photodetector of claim 15 wherein the hole transporting layers and the electron transporting layers of the plurality of pairs are selected to have spectral sensitivity in the visible spectrum.

21. The photodetector of claim 15 wherein each hole transporting layer comprises copper phthalocyanine (CuPc) and each electron transporting layer comprises 3,4,9, 10-perylenetetracarboxylic-bis-benzimidazole (PTCBI).

22. The photodetector of claim 15 wherein the plurality of pairs is at least 5 pairs.

23. The photodetector of claim 15 wherein the plurality of pairs is at least 10 pairs.

24. The photodetector of claim 15 wherein the exciton blocking layer is disposed between the anode and the plurality of pairs and a second exciton blocking layer is disposed between t he cathode and the plurality of pairs.