Organic electroluminescent transistor

Patent metadata

Field	Value
Publication number	US-10964919-B2
Application number	US-201715413838-A
Country	US
Kind code	B2
Filing date	Jan 24, 2017
Priority date	Jul 24, 2014
Publication date	Mar 30, 2021
Grant date	Mar 30, 2021

Abstract

The present teachings relate to an organic electroluminescent transistor with improved light-emission characteristics. More specifically, the present organic electroluminescent transistor has an emissive ambipolar channel including at least one layer of an n-type semiconductor material, at least one layer of a p-type semiconductor material, and at least one layer of an emissive material arranged between the layers of the p-type and n-type semiconductor materials, where the multilayer emissive ambipolar channel includes, among various layers, a layer of a p-type semiconductor material comprising a benzothieno-benzothiophene compound, and/or a layer of an emissive material comprising a blend material that includes an organic carbazole derivative as the host matrix compound and an iridium complex as the guest emitter.

First claim

The invention claimed is:

1. An organic electroluminescent transistor comprising: at least one dielectric layer; at least one control electrode; at least one drain electrode; at least one source electrode; and an assembly comprising an emissive ambipolar channel, wherein:
said dielectric layer is arranged between said control electrode and said assembly;
said emissive ambipolar channel comprises at least one layer of an n-type semiconductor material, at least one layer of a p-type semiconductor material, and at least one layer of an emissive material arranged between said layers of p-type and n-type semiconductor materials, the emissive material including a fluorescent or phosphorescent emitter;
said p-type semiconductor material comprises a benzothieno-benzothiophene compound of formula (P-I)

 wherein R a and R b are independently selected from the group consisting of H, a C 1-18 alkyl group, and a C 6-14 aryl group;
said n-type semiconductor material comprises a bis(p-fluoroalkyl)phenyl-substituted oligomeric thiophene compound, wherein the oligomeric thiophene compound has 2, 3, 4, 5 or 6 thiophene moieties; and
said emissive material comprises a blend material comprising an organic carbazole derivative as a host matrix compound and an iridium complex as a guest emitter.

2. The organic electroluminescent transistor according to claim 1 , wherein said p-type semiconductor material comprises a benzothieno-benzothiophene compound of formula

3. The organic electroluminescent transistor according to claim 1 where said p-type semiconductor material comprises a benzothieno-benzothiophene compound of formula

4. The organic electroluminescent transistor according to claim 2 , wherein R a and R b are identical linear C 3-12 alkyl groups.

5. The organic electroluminescent transistor according to claim 1 , wherein said p-type semiconductor material comprises a compound of the formula

wherein each R is a phenyl group.

6. The organic electroluminescent transistor according to claim 1 , wherein two or more of the thiophene moieties of the bis(p-fluoroalkyl)phenyl-substituted oligomeric thiophene compound are fused.

7. The organic electroluminescent transistor according to claim 6 , wherein the bis(p-fluoroalkyl)phenyl-substituted oligomeric thiophene compound is a thienothiophene having the structural formula

wherein Ar and Ar′ are phenyl, m and m′ are 1, and R 1 and R 2 are independently fluoroalkyl.

8. The organic electroluminescent transistor according to claim 1 , wherein the thickness of said layer of p-type semiconductor material is between 5 and 50 nm.

9. The organic electroluminescent transistor according to claim 1 , characterized in that the thickness of said layer of n-type semiconductor material is between 30 nm and 60 nm.

10. The organic electroluminescent transistor according to claim 9 , wherein the thickness of said layer of p-type semiconductor material is between 15 and 45 nm.

11. The organic electroluminescent transistor according to claim 1 , characterized in that said layer of emissive material has a thickness between 30 nm and 60 nm.

12. The organic electroluminescent transistor according to claim 1 , wherein the organic carbazole derivative and the iridium complex are selected from the group consisting of:

13. The organic electroluminescent transistor according to claim 1 , wherein said source electrode is in contact with said layer of p-type semiconductor material and said drain electrode is in contact with said layer of n-type semiconductor material.

14. The organic electroluminescent transistor according to claim 1 , wherein said source electrode and said drain electrode are composed of at least one different material.

15. The organic electroluminescent transistor according to claim 1 , wherein an injection sublayer is interposed between said source electrode and the layer of p-type or n-type semiconductor material and/or an injection sublayer is interposed between said drain electrode and the layer of the p-type or n-type semiconductor material.

16. The organic electroluminescent transistor according to claim 1 , wherein each of the control electrode, drain electrode, and source electrode independently comprises a metal or a transparent conducting oxide selected from the group consisting of gold, silver, molybdenum, copper, titanium, chromium, tin-doped indium oxide and combination thereof.

17. The organic electroluminescent transistor according to claim 1 , wherein the dielectric layer comprises an electrically insulating material selected from the group consisting of an inorganic oxide or nitride, a molecular dielectric, a polymeric dielectric, and combination thereof.

18. The organic electroluminescent transistor according to claim 17 , wherein the inorganic oxide or nitride is selected from the group consisting of SiO 2 , Si 3 N 4 , Al 2 O 3 , ZrO x , Al-doped ZrO x , and HfO x .

19. The organic electroluminescent transistor according to claim 1 , further comprising a passivation layer covering a top surface of the emissive ambipolar channel.

20. An optoelectronic device for producing an image, the optoelectronic device comprising a plurality of identical or different organic electroluminescent transistors according to claim 1 , interconnected to each other and deposited on a substrate.

Assignees

• Flexterra Inc

Inventors

• Biondo Viviana
• Generali Gianluca
• Stefani Andrea
• Muccini Michele
• Turatti Guido
• Denti Mitchell
• Usta Hakan
• Chen Xiaoyan
• Facchetti Antonio

Classifications

• C07D495/04

  Ortho-condensed systems · CPC title

• H01L51/0085

  Electricity · mapped topic

• H01L51/5012

  Electricity · mapped topic

• H01L2251/308

  Electricity · mapped topic

• H01L2251/305

  Electricity · mapped topic