Method for making electronic devices using metal oxide nanoparticles

• US 7,507,618 B2
• Filed: 06/27/2005
• Issued: 03/24/2009
• Est. Priority Date: 06/27/2005
• Status: Expired due to Fees

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Dunbar, Timothy D.
• Primary Examiner(s): Tran; Long K
• Application Number:
  US11/167,800
• Publication Number:
  US 20060292777A1
• Time in Patent Office: 1,366 Days
• Field of Search: 438/197, 438/231, 438/233, 438/698, 438/722, 65/172, 65/173, 65/605, 651/73, 977/811, 977/715, 56/605
• US Class Current: 438/197
• CPC Class Codes: H01L 21/02554 Oxides
• CPC Class Codes: H01L 21/02565 Oxide semiconducting materials not being Group 12/16 materials, e.g. ternary compounds
• CPC Class Codes: H01L 21/02601 Nanoparticles fullerenes H10K85/211
• CPC Class Codes: H01L 21/02628 using solutions
• CPC Class Codes: H01L 29/66969 of devices having semiconductor bodies not comprising group 14 or group 13/15 materials comprising selenium or tellurium in uncombined form other than as impurities in semiconductor bodies of other materials, comprising cuprous oxide or cuprous iodide H01L21/02365
• CPC Class Codes: H01L 29/78603 characterised by the insulating substrate or support H01L29/78657 takes precedence
• CPC Class Codes: H01L 29/78681 having a semiconductor body comprising AIIIBV or AIIBVI or AIVBVI semiconductor materials, or Se or Te
• CPC Class Codes: H01L 29/7869 having a semiconductor body comprising an oxide semiconductor material, e.g. zinc oxide, copper aluminium oxide, cadmium stannate
• CPC Class Codes: Y10S 977/811 Of specified metal oxide composition, e.g. conducting or semiconducting compositions such as ITO, ZnOx

Abstract

A method of making a thin film transistor comprises (a) solution depositing a dispersion comprising semiconducting metal oxide nanoparticles onto a substrate, (b) sintering the nanoparticles to form a semiconductor layer, and (c) optionally subjecting the resulting semiconductor layer to post-deposition processing.

Claims

1. A method of making a thin film transistor comprising:

(a) solution depositing a dispersion comprising semiconducting metal oxide nanoparticles onto a substrate;

(b) sintering the nanoparticles at a temperature less than about 150°

C. to form a semiconductor layer of a thin film transistor; and

(c) optionally subjecting the resulting semiconductor layer to post-deposition processing;

wherein sintering is accomplished using ultraviolet light or ozone treatment, or a combination thereof, and optionally heat.

2. The method of claim 1 wherein the nanoparticles comprise zinc oxide or tin oxide, or a combination thereof.

3. The method of claim 2 wherein the nanoparticles comprise zinc oxide.

4. The method of claim 1 wherein the nanoparticles comprise a doped insulating material.

5. The method of claim 1 wherein the nanoparticles comprise a metal oxide having a Hall mobility greater than about 1 cm² V⁻

1 s<sup>−

1</sup>.

6. The method of claim 5 wherein the nanoparticles comprise a metal oxide having a Hall mobility greater than about 10 cm² V⁻

1 s<sup>−

1</sup>.

7. The method of claim 1 wherein the nanoparticles comprise a transparent metal oxide.

8. The method of claim 1 wherein the nanoparticles arc synthesized using an organometallic precursor method.

9. The method of claim 1 wherein the dispersion comprises a bimodal or multimodal size distribution of nanoparticles.

10. The method of claim 1 wherein the dispersion is deposited by spin coating or a printing technique.

11. The method of claim 1 wherein the substrate is a dielectric layer.

12. The method of claim 1 wherein the thin film transistor comprises a polymeric transistor substrate.

13. The method of claim 12 wherein the thin film transistor comprises a flexible polymeric transistor substrate.

14. The method of claim 1 wherein the resulting semiconductor layer is subjected to post-deposition processing.

15. The method of claim 14 wherein the resulting thin film transistor is subjected to a second post-deposition processing.

16. The method of claim 14 wherein the resulting thin film transistor is annealed in air, annealed in forming gas, treated with atomic hydrogen, or aged at ambient conditions.

17. The method of claim 16 wherein the resulting thin film transistor is annealed in forming gas.

18. A thin film transistor comprising a semiconductor layer made by the method of claim 1.

19. A method of making an electronic device comprising:

(a) solution depositing a dispersion comprising metal oxide nanoparticles onto a substrate; and

(b) exposing the nanoparticles to ultraviolet light or oxidation treatment, or a combination thereof at a temperature less than about 150°

C. to form a device layer, wherein the device layer is a semiconductor layer or an electrode layer.

20. The method of claim 19 wherein the nanoparticles comprise zinc oxide or tin oxide, or a combination thereof.

21. The method of claim 19 wherein the nanoparticles comprise a doped insulating material.

22. The method of claim 19 wherein the nanoparticles comprise a metal oxide having a Hall mobility greater than about 1 cm² V⁻

1 s<sup>−

1</sup> or a resistivity less than about 10<sup>−

2</sup> Ω

-cm.

23. The method of claim 19 wherein the nanoparticles comprise a transparent metal oxide.

24. The method of claim 19 wherein the nanoparticles are exposed to ultraviolet light to form the device layer.

25. The method of claim 19 wherein the nanoparticles are exposed to ultraviolet light and ozone to form the device layer.

26. The method of claim 19 wherein the electronic device is a sensor.

27. An electronic device comprising a semiconductor layer or an electrode layer made by the method of claim 19.

28. A method of making an electronic device comprising:

(a) solution depositing a dispersion comprising metal oxide nanoparticles onto a substrate; and

(b) exposing the nanoparticles to ultraviolet light or oxidation treatment, or a combination thereof at a temperature less than about 150°

C. to form a device layer;

wherein the electronic device is a sensor.