Functional organic thin film, organic thin-film transistor, pi-electron conjugated molecule-containing silicon compound, and methods of forming them

A process for preparing a functional organic thin film comprising forming a functional organic thin film on a substrate by a chemical adsorption method using a silicon compound represented the formula:

• R—SiX1X2X3 (I),
• wherein R is an organic residue in which a plurality of π-electron conjugated units having a terminus optionally substituted with a functional group are bound, and X1, X2 and X3 are, the same or different, is a group which affords hydroxyl group by hydrolysis.

A functional organic thin film comprising a first monomolecular film derived from a silicon compound represented by the formula:

• R—SiX1X2X3 (I),
• wherein R is an organic residue in which a plurality of π-electron conjugated units having a terminus optionally substituted with a functional group are bound, and X1, X2 and X3 are, the same or different, a group which affords hydroxyl group by hydrolysis, and a second monomolecular film containing a silicon compound in which a plurality π-electron conjugated units are bound on a substrate, said second monomolecular film being formed on the first monomolecular film at the number of one or more.

A process for preparing a functional organic thin film comprising steps of:

• making a first monomolecular film on a substrate by a chemical adsorption method using a silicon compound represented by the formula:
• R—SiX1X2X3 (I),
• wherein R is an organic residue in which a plurality of π-electron conjugated units having a terminus optionally substituted with a functional group are bound, and X1, X2 and X3 are, the same or different, a group which affords hydroxyl group by hydrolysis, and forming at least one second monomolecular film containing a silicon compound in which a plurality of π-electron conjugated units are bound, on the first monomolecular film using a chemical adsorption method.

An organic thin film transistor comprising a substrate, an organic thin film of a monomolecular film of a silicon compound represented by the formula:

• R—SiX1X2X3 (I),
• wherein R is an organic residue in which a plurality of π-electron conjugated units having a terminus optionally substituted with a functional group are bound, and X1, X2 and X3 are, the same or different, a group which affords a hydroxyl group by hydrolysis, or an accumulated monomolecular film;
• a gate electrode which is formed on one surface of the organic thin film via a gate insulating film, and source/drain electrodes formed in contact with one surface or the other surface of the organic thin film on both sides of the gate electrode.

An organic thin film transistor comprising a substrate, an organic thin film, a gate electrode formed on one surface of the organic thin film via an insulating film, and source/drain electrodes formed in contact with one surface or the other surface of the organic thin film on both sides of the gate electrode, wherein the organic thin film comprises a first monomolecular film formed using a silicon compound represented by the formula:

• R—SiX1X2X3 (I),
• wherein R is an organic residue in which a plurality of π-electron conjugated units having a terminus optionally substituted with a functional group are bound, and X1, X2 and X3 are, the same or different, a group which affords hydroxyl group by hydrolysis, and at least one second monomolecular film containing a silicon compound in which a plurality of π-electron conjugated units are bound, formed on the first monomolecular film.

A process for preparing an organic thin film transistor comprising a substrate, an organic thin film, a gate electrode formed on one surface of the organic thin film via a gate insulating film, and source/drain electrodes formed in contact with one surface or the other surface of the organic thin film on both sides of the gate electrode, which comprises forming the organic thin film as a monomolecular film or an accumulated monomolecular film, using a silicon compound represented by the formula:

• R—SiX1X2X3 (I),
• wherein R is an organic residue in which a plurality of π-electron conjugated units having a terminus optionally substituted with a functional group are bound, and X1, X2 and X3 are, the same or different, a group which affords hydroxyl group by hydrolysis.

A π-electron conjugated molecule-containing silicon compound represented by the formula:

• R1—SiX1X2X3 (I)′,
• wherein R is an organic residue in which a plurality of π-electron conjugated units having a terminus optionally substituted with a functional group are bound, and X1, X2 and X3 are, the same or different, a group which affords hydroxyl group by hydrolysis.

A π-electron conjugated molecule-containing silicon compound represented by the formula:

• R1—SiX1X2X3 (I)′,
• wherein R1 is a π-electron conjugated organic residue in which 3 to 10 units selected from the group derived from a monocyclic aromatic hydrocarbons and a monocyclic heterocycle compound are bound, and may have a functional group at a terminus, and X1, X2 and X3 are, the same or different, a group which affords hydroxyl group by hydrolysis.