Electronic devices

• US 20060214312A1
• Filed: 03/23/2005
• Published: 09/28/2006
• Est. Priority Date: 03/23/2005
• Status: Active Grant

• Current Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Original Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Inventors: Wu, Yiliang, Liu, Ping, Ong, Beng S.
• Granted Patent: US 8,089,062 B2
• Time in Patent Office: Days
• US Class Current: 257/787
• CPC Class Codes: H10K 10/466 Lateral bottom-gate IGFETs comprising only a single gate
• CPC Class Codes: H10K 10/80 Constructional details
• CPC Class Codes: H10K 30/88 Passivation; Containers; Encapsulations
• CPC Class Codes: H10K 50/844 Encapsulations
• CPC Class Codes: H10K 59/873 Encapsulations

Abstract

An electronic device comprising: a substrate, an active layer, and an encapsulating layer comprising at least one wax.

Claims

1. An electronic device comprising a substrate, an active layer, and an encapsulating layer comprising at least one wax.

2. A device in accordance with claim 1 wherein said device is an organic thin film transistor.

3. A device in accordance with claim 1 wherein the encapsulation layer is in contact with the active layer.

4. A device in accordance with claim 1 wherein said wax is selected from the group comprised of natural vegetable waxes, natural animal waxes, mineral waxes, synthetic waxes, and functionalized waxes, and mixtures thereof.

5. A device in accordance with claim 4 wherein said natural vegetable waxes are selected from the group consisting of carnauba wax, candelilla wax, Japan wax, and bayberry wax, and mixtures thereof.

6. A device in accordance with claim 4 wherein said natural animal waxes are selected from the group consisting of beeswax, punic wax, lanolin, lac wax, shellac wax, and spermaceti wax, and mixtures thereof.

7. A device in accordance with claim 4 wherein said mineral waxes are selected from the group consisting of paraffin wax, microcrystalline wax, montan wax, ozokerite wax, ceresin wax, petrolatum wax, petroleum wax, and mixtures thereof.

8. A device in accordance with claim 4 wherein said synthetic waxes are selected from the group consisting of Fischer-Tropsch wax, acrylate wax, fatty acid amide wax, silicone wax, polytetrafluoroethylene wax, polyethylene wax, polypropylene wax, and mixtures thereof.

9. A device in accordance with claim 1 wherein said wax is a polyalkylene wax.

10. A device in accordance with claim 9 wherein said polyalkylene has an average molecular weight of from about 500 to about 25,000, and wherein the alkylene contains from 1 to about 20 carbon atoms.

11. A device in accordance with claim 9 wherein said polyalkylene is comprised of a mixture of polyethylene and polypropylene.

12. A device in accordance with claim 9 wherein said polyalkylene is a polyethylene.

13. A device in accordance with claim 9 wherein said polyalkylene is a polypropylene.

14. A device in accordance with claim 1 further containing in said encapsulating layer additives selected from the group consisting of at least one of pigments, dyes, metal oxides, crosslinking components, and mixtures thereof.

15. A device in accordance with claim 14 wherein the pigments or dyes are selected from the group consisting of black, cyan, magenta, yellow, red, green, brown, blue pigments and dyes, and mixtures thereof;

said metal oxides are selected from the group consisting of aluminum oxides, strontiates, tantalates, titanates, zirconates, silicon oxides, tantalum oxides, titanium oxides, silicon nitrides, barium titanate, and mixtures thereof; and

optionally wherein said crosslinking agents are selected from components containing two or more isocyanate groups, compounds containing two or more epoxy groups, compounds containing two or more carboxylic acid groups and acid anhydrides of carboxylic acid, compounds containing two or more vinyl groups, compounds containing two or more acrylates groups, and mixtures thereof.

16. A device in accordance with claim 1 wherein said wax possesses crystalline or semicrystalline characteristics.

17. A device in accordance with claim 1 wherein said active layer is a semiconductor layer optionally comprised of a polythiophene.

18. A device in accordance with claim 1 wherein said active layer is a semiconductor layer comprising a polythiophene of the formula

19. A device in accordance with claim 1 wherein said device is a thin film transistor and said active layer is a polythiophene represented by

22. A process comprising

providing the electronic device of claim 1;

and

depositing a wax encapsulation layer on the electronic device to separate the electronic device from its environment.

23. A process in accordance with claim 22 wherein said wax is deposited from a wax composition in a solvent, or a melted wax composition, and wherein said deposition is accomplished by printing methods.

24. A process in accordance with claim 1 wherein said at least one is from one to about three.

20. A thin film transistor comprising

a substrate;

a gate electrode;

a semiconductor layer;

a gate dielectric layer;

a source electrode;

a drain electrode;

and a layer thereover comprising a wax and optional additives wherein the gate dielectric layer, the gate electrode, the semiconductor layer, the source electrode, and the drain electrode are in any sequence providing that said gate electrode and said semiconductor layer both contact the gate dielectric layer, and the source electrode and the drain electrode both contact the semiconductor layer.

21. A thin film transistor in accordance with claim 20 wherein the wax is a polyalkylene, and the semiconductor layer comprises a polythiophene.

25. A thin film transistor comprised of a substrate, an active polythiophene layer, and which layer is in contact with a wax.