# US 7,407,846 B2 · Thin film transistor, display device and their production > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,407,846 B2 - Document ID: US7407846B2 - Status: Granted - Kind: B2 - Application number: 11/672,908 - Filed: 2007-02-08 - Published: 2007-06-07 - Granted: 2008-08-05 - Earliest claimed: 2003-09-04 - Assignees: Hitachi, Ltd. - Inventors: Masahiko Ando; Masatoshi Wakagi; Hiroshi Sasaki - Web page: https://patentgrep.com/patent/US7407846B2 ## CPC - H10K 10/466: {Lateral bottom-gate IGFETs comprising only a single gate} - B82Y 10/00: Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic - B82Y 30/00: Nanotechnology for materials or surface science, e.g. nanocomposites - H10K 10/476: {comprising at least one organic layer and at least one inorganic layer} - H10K 71/191: {characterised by provisions for the orientation or alignment of the layer to be deposited} - H10K 71/60: Forming conductive regions or layers, e.g. electrodes - H10K 71/621: {Providing a shape to conductive layers, e.g. patterning or selective deposition} - H10K 85/113: {Heteroaromatic compounds comprising sulfur or selene, e.g. polythiophene} - H10K 85/115: {Polyfluorene; Derivatives thereof} - H10K: ORGANIC ELECTRIC SOLID-STATE DEVICES - B82Y: SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES ## Abstract The present method prevents malfunctions in switching caused by a light leakage current in an active matrix type thin film transistor substrate for a liquid crystal display and prevents display failures, by selectively disposing a self assembled monolayer film in a gate electrode-projected region of the surface of an insulator film with high definition, and by selectively improving the orientation order of an organic semiconductor film only in the gate electrode-projected region without improving the order at an irradiated portion with light outside the gate electrode-projected region. ## Claims ### Claim 1 A method for manufacturing a thin film transistor comprising the steps of: forming a gate electrode on a substrate, forming an insulation film on the gate electrode, forming a self assembled monolayer film within a gate electrode-projected region and on the insulation film, forming a semiconductor film on the insulation film and the self assembled monolayer film, the semiconductor film being composed of an aggregate of organic semiconductor molecules, and forming a source electrode and drain electrode on the insulation film and the semiconductor film. ### Claim 2 (depends on 1) The method according to claim 1, wherein the self assembled monolayer film is formed in approximately the same pattern shape as the gate electrode. ### Claim 3 (depends on 1) The method according to claim 1, wherein the step of forming the self assembled monolayer film within the gate electrode-projected region includes the sub-steps of: forming the self assembled monolayer film on the insulation film, applying a photoresist onto the self assembled monolayer film, exposing the applied photoresist to light through a photomask that shades a gate electrode-projected region, and removing the photoresist formed in the region outside the gate electrode-projected region, etching and removing the self assembled monolayer film formed in the region outside the gate electrode-projected region using a pattern of the photoresist as a mask, and removing the photoresist. ### Claim 4 (depends on 1) The method according to claim 1, wherein the steps of forming the self assembled monolayer film includes the sub-steps of: forming the self assembled monolayer film on the insulation film, applying photoresist onto the self assembled monolayer film, exposing the applied photoresist to light from a side of the substrate opposite to a side on which the gate electrode is formed, and removing the photoresist formed in the region outside the gate electrode-projected region, etching and removing the self assembled monolayer film formed in the region outside the gate electrode-projected region using a pattern of the photoresist as a mask, and removing the photoresist. ### Claim 5 (depends on 1) The method according to claim 1, wherein the steps of forming the self assembled monolayer film includes the sub-steps of: forming the self assembled monolayer film on the insulation film, and exposing the substrate to light from a side of the substrate opposite to a side on which the gate electrode is formed, and removing the self assembled monolayer film formed in the region outside the gate electrode-projected region. ### Claim 6 (depends on 5) The method according to claim 5, wherein the self assembled monolayer film is composed of a photodecomposable material which is decomposed and removed by a light with a wavelength transmitting the substrate and the insulation film. ### Claim 7 A method for manufacturing a thin film transistor comprising the steps of: forming a gate electrode on a substrate, forming an insulation film on the gate electrode, forming a self assembled monolayer film within a gate electrode-projected region and on the insulation film, applying and burning an electroconductive ink on the insulation film to form a source electrode and drain electrode, forming a semiconductor film on the source electrode and drain electrode and on the self assembled monolayer film, the semiconductor film being composed of an aggregate of organic semiconductor molecules. ### Claim 8 (depends on 7) The method according to claim 7, wherein the self assembled monolayer film is formed in approximately the same pattern shape as the gate electrode. ### Claim 9 (depends on 7) The method according to claim 7, wherein the step of forming the self assembled monolayer film within the gate electrode-projected region includes the sub-step of: forming the self assembled monolayer film on the insulation film, applying a photoresist onto the self assembled monolayer film, exposing the applied photoresist to light through a photomask that shades a gate electrode-projected region, and removing the photoresist formed in the region outside the gate electrode-projected region, etching and removing the self assembled monolayer film formed in the region outside the gate electrode-projected region using a pattern of the photoresist as a mask, and removing the photoresist. ### Claim 10 (depends on 7) The method according to claim 7, wherein the step of forming the self assembled monolayer film within the gate electrode-projected region includes the sub-steps of: forming the self assembled monolayer film on the insulation film, applying the photoresist onto the self assembled monolayer film, exposing the applied photoresist to light from a side of the substrate opposite to a side on which the gate electrode is formed, and removing the photoresist formed in the region outside the gate electrode-projected region, etching and removing the self assembled monolayer film formed in the region outside the gate electrode-projected region using a pattern of the photoresist as a mask, and removing the photoresist. ### Claim 11 (depends on 7) The method according to claim 7, wherein the step of forming the self assembled monolayer film within the gate electrode-projected region includes the sub-steps of: forming the self assembled monolayer film on the insulation film, exposing the substrate to light from a side of the substrate opposite to a side on which the gate electrode is formed, and removing the self assembled monolayer film formed in the region outside the gate electrode-projected region. ### Claim 12 (depends on 11) The method according to claim 11, wherein the self assembled monolayer film is composed of a photodecomposable material which is decomposed and removed by a light with a wavelength transmitting the substrate and the insulation film.