Organic-inorganic hybrid multilayer gate dielectrics for thin-film transistors
Disclosed are organic-inorganic hybrid self-assembled multilayers that can be used as electrically insulating (or dielectric) materials. These multilayers generally include an inorganic primer layer and one or more bilayers deposited thereon. Each bilayer includes a chromophore or “π-polarizable” layer and an inorganic capping layer composed of zirconia. Because of the regularity of the bilayer structure and the aligned orientation of the chromophore resulting from the self-assembly process, the present multilayers have applications in electronic devices such as thin film transistors, as well as in nonlinear optics and nonvolatile memories.
1. A thin film transistor comprising an organic-inorganic hybrid multilayer dielectric material, a gate electrode in contact with the organic-inorganic hybrid multilayer dielectric material, a thin film semiconductor, and source and drain electrodes in contact with the thin film semiconductor, wherein the organic-inorganic hybrid multilayer dielectric material comprises an inorganic primer layer and one or more bilayers deposited thereon, each bilayer comprising a π-polarizable layer and an inorganic oxide capping layer, wherein the inorganic oxide capping layer in each bilayer is coupled to the π-polarizable layer via bonds other than phosphonate bonds.
2. The thin film transistor of claim 1 , wherein each bilayer comprises a condensation product of a π-polarizable compound and an inorganic oxide precursor sol.
3. The thin film transistor of claim 1 , wherein the inorganic oxide capping layer comprises zirconia.
4. The thin film transistor of claim 1 , wherein the π-polarizable compound is selected from
wherein X is H or a protecting group, and n is an integer between 1 and 20.
5. The thin film transistor of claim 4 , wherein the inorganic primer layer and the first bilayer of said one or more bilayers deposited thereon comprises the structure:
6. The thin film transistor of claim 1 , wherein the thin film semiconductor comprises a semiconducting molecule or a semiconducting polymer.
7. The thin film transistor of claim 6 , wherein an n-alkylphosphonic acid self-assembled monolayer is present between the organic-inorganic hybrid multilayer dielectric material and the thin film semiconductor.
8. The thin film transistor of claim 1 , wherein the thin film semiconductor comprises a metal oxide selected from indium oxide (In 2 O 3 ), indium zinc oxide (IZO), zinc tin oxide (ZTO), indium gallium oxide (IGO), indium-gallium-zinc oxide (IGZO), tin oxide (SnO 2 ), and zinc oxide (ZnO).