METHOD AND APPARATUS FOR OPTICALLY TRANSPARENT TRANSISTOR

• US 20100163861A1
• Filed: 12/29/2008
• Published: 07/01/2010
• Est. Priority Date: 12/29/2008
• Status: Abandoned Application

• Current Assignee: Motorola Solutions, Inc.
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Brazis, Paul W. JR.
• Application Number:
  US12/344,775
• Publication Number:
  US 20100163861A1
• Time in Patent Office: Days
• US Class Current: 257/43
• CPC Class Codes: H01L 29/45 Ohmic electrodes
• CPC Class Codes: H01L 29/4908 for thin film semiconductor, e.g. gate of TFT
• CPC Class Codes: H01L 29/7869 having a semiconductor body comprising an oxide semiconductor material, e.g. zinc oxide, copper aluminium oxide, cadmium stannate

Abstract

A method and apparatus for an optically transparent field effect transistor on a substrate. The gate electrode, the dielectric, the semiconducting layer, the source electrode, and the drain electrode are optically transparent layers of nanoparticles that are formed using one or more graphic arts printing processes. The dielectric layer is in contact with the gate electrode, the semiconducting layer is in contact with the dielectric layer, and the source and drain electrodes are in contact with the semiconducting layer.

Claims

1. An optically transparent field effect transistor situated on an insulating substrate, comprising:

a substantially transparent gate electrode consisting of indium tin oxide nanoparticles or antimony tin oxide nanoparticles;

a substantially transparent dielectric layer in contact with the substantially transparent gate electrode, comprising aluminum oxide or silicon dioxide nanoparticles dispersed in a polymer;

a substantially transparent semiconducting layer in contact with the substantially transparent dielectric layer, comprising nanoparticles of a wide bandgap doped or undoped material selected from the group consisting of zinc oxide, tin oxide, zinc sulfide and gallium nitride;

a substantially transparent source electrode in contact with the substantially transparent semiconducting layer, consisting of indium tin oxide nanoparticles or antimony tin oxide nanoparticles; and

a substantially transparent drain electrode in contact with the substantially transparent semiconducting layer, consisting of indium tin oxide nanoparticles or antimony tin oxide nanoparticles.

2. The optically transparent field effect transistor as described in claim 1, wherein the dielectric layer, the gate electrode, the semiconducting layer, the source electrode, and the drain electrode are in any sequence as long as the gate electrode and the semiconducting layer both contact the dielectric layer, and the source electrode and the drain electrode both contact the semiconducting layer.

3. The optically transparent field effect transistor as described in claim 1, wherein the insulating substrate is substantially transparent.

4. The optically transparent field effect transistor as described in claim 1, wherein nanoparticles have a diameter less than 100 nanometers.

5. The optically transparent field effect transistor as described in claim 1, wherein the indium tin oxide, antimony tin oxide, aluminum oxide, silicon dioxide, zinc oxide, tin oxide, zinc sulfide or gallium nitride nanoparticles further comprise a binding agent.

6. The optically transparent field effect transistor as described in claim 5, wherein the binding agent comprises polyvinyl phenol.

7. The optically transparent field effect transistor as described in claim 5, wherein the binding agent comprises less than 5% by weight of the nanoparticles.

8. An optically transparent field effect transistor situated on an insulating substrate, comprising:

a substantially transparent gate electrode consisting of a thin film of vacuum deposited indium tin oxide or antimony tin oxide;

a substantially transparent dielectric layer in contact with the substantially transparent gate electrode, comprising aluminum oxide or silicon dioxide nanoparticles dispersed in a polymeric binder;

a substantially transparent semiconducting layer in contact with the substantially transparent dielectric layer, comprising nanoparticles of a doped or undoped material selected from the group consisting of zinc oxide, tin oxide, zinc sulfide and gallium nitride;

a substantially transparent source electrode in contact with the substantially transparent semiconducting layer, consisting of indium tin oxide nanoparticles or antimony tin oxide nanoparticles; and

a substantially transparent drain electrode in contact with the substantially transparent semiconducting layer, consisting of indium tin oxide nanoparticles or antimony tin oxide nanoparticles; and

wherein the dielectric layer, the gate electrode, the semiconducting layer, the source electrode, and the drain electrode are in any sequence as long as the gate electrode and the semiconducting layer both contact the dielectric layer, and the source electrode and the drain electrode both contact the semiconducting layer.

9. The optically transparent field effect transistor as described in claim 8, wherein the insulating substrate is substantially transparent.

10. The optically transparent field effect transistor as described in claim 8, wherein nanoparticles have a diameter less than 100 nanometers.

11. The optically transparent field effect transistor as described in claim 8, wherein the indium tin oxide, antimony tin oxide, aluminum oxide, silicon dioxide, zinc oxide, tin oxide, zinc sulfide or gallium nitride nanoparticles further comprise a binding agent.

12. The optically transparent field effect transistor as described in claim 11, wherein the binding agent comprises polyvinyl phenol.

13. The optically transparent field effect transistor as described in claim 11, wherein the binding agent comprises less than 5% by weight of the nanoparticles.

14. A method of forming an optically transparent field effect transistor on an insulating substrate, utilizing graphic arts printing processes, comprising:

forming a substantially transparent gate electrode by printing a suspension of indium tin oxide or antimony tin oxide nanoparticles in a carrier solvent;

forming a substantially transparent dielectric layer by printing a suspension of aluminum oxide or silicon dioxide nanoparticles dispersed in a polymeric binder;

forming a substantially transparent semiconducting layer by printing a suspension of nanoparticles selected from the group consisting of zinc oxide, tin oxide, zinc sulfide and gallium nitride in a carrier solvent;

forming substantially transparent source and drain electrodes by printing a suspension of indium tin oxide or antimony tin oxide nanoparticles in a carrier solvent;

baking the transistor to substantially remove the carrier solvents; and

wherein forming the gate electrode, forming the dielectric layer, forming the semiconducting layer, forming the source and drain electrodes, and baking the transistor are in any sequence as long as the gate electrode and the semiconducting layer both contact the dielectric layer, and the source electrode and the drain electrode both contact the semiconducting layer.

15. The method of forming an optically transparent field effect transistor as described in claim 14, further comprising heating the optically transparent transistor sufficient to increase optical transparency.

16. The method of forming an optically transparent field effect transistor as described in claim 15, wherein heating the transistor comprises heating at a temperature greater than 200 degrees Centigrade.

17. The method of forming an optically transparent field effect transistor as described in claim 14, further comprising a binding agent in the suspension of indium tin oxide, antimony tin oxide, aluminum oxide, silicon dioxide, zinc oxide, tin oxide, zinc sulfide or gallium nitride nanoparticles.

18. The method of forming an transparent field effect transistor as described in claim 17, wherein the binding agent comprises polyvinyl phenol.

19. The method of forming an optically transparent field effect transistor as described in claim 17, wherein the binding agent comprises less than 5% by weight of the suspension.