Active matrix display device

• US 7,939,822 B2
• Filed: 12/30/2008
• Issued: 05/10/2011
• Est. Priority Date: 02/03/2005
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Kuwabara, Hideaki, Maekawa, Shinji
• Primary Examiner(s): Smith; Bradley K
• Assistant Examiner(s): Valentine; Jami M
• Application Number:
  US12/346,250
• Publication Number:
  US 20090152541A1
• Time in Patent Office: 861 Days
• Field of Search: 257/43, 257/72, 257/E29.292, 257/E27.06, 257/E21.017, 257/E21.02, 257/E21.028, 438/159, 438/161, 438/163, 438/401, 438/669
• US Class Current: 257/43
• CPC Class Codes: H01L 29/41733 for thin film transistors with insulated gate
• CPC Class Codes: H01L 29/458 for thin film silicon, e.g. source or drain electrode
• CPC Class Codes: H01L 29/66765 Lateral single gate single channel transistors with inverted structure, i.e. the channel layer is formed after the gate
• CPC Class Codes: H01L 29/78678 with inverted-type structure, e.g. with bottom gate
• 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

The present invention provides a manufacturing process using a droplet-discharging method that is suitable for manufacturing a large substrate in mass production. A photosensitive material solution of a conductive film is selectively discharged by a droplet-discharging method, selectively exposed to laser light, and developed or etched, thereby allowing only the region exposed to laser light to be left and realizing a source wiring and a drain wiring having a more microscopic pattern than the pattern itself formed by discharging. One feature of the source wiring and the drain wiring is that the source wiring and the drain wiring cross an island-like semiconductor layer and overlap it.

Claims

1. An active matrix liquid crystal display device comprising:

a thin film transistor formed over a substrate, the thin film transistor comprising;

a gate electrode;

a gate insulating film formed over the gate electrode; and

a semiconductor film comprising a metal oxide wherein the metal oxide is In—

Ga—

Zn—

O;

a first inorganic insulating film formed on the semiconductor film;

a second insulating film formed over the first inorganic insulating film; and

a pixel electrode formed on the second insulating film and electrically connected to the thin film transistor,

wherein the second insulating film is formed from a material solution.

2. An active matrix EL display device comprising:

a thin film transistor formed over a substrate, the thin film transistor comprising;

a gate electrode;

a gate insulating film formed over the gate electrode; and

a semiconductor film comprising a metal oxide wherein the metal oxide is In—

Ga—

Zn—

O;

a first inorganic insulating film formed on the semiconductor film;

a second insulating film formed over the first inorganic insulating film;

a pixel electrode formed on the second insulating film and electrically connected to the thin film transistor;

wherein the second insulating film is formed from a material solution.

3. An active matrix liquid crystal display device comprising:

a thin film transistor formed over a substrate, the thin film transistor comprising;

a gate electrode;

a gate insulating film formed over the gate electrode; and

a semiconductor film comprising a metal oxide wherein the metal oxide is In—

Ga—

Zn—

O;

a first inorganic insulating film formed on the semiconductor film;

a second insulating film having a planarized upper surface formed over the first inorganic insulating film; and

a pixel electrode formed over the second insulating film and electrically connected to the thin film transistor.

4. The active matrix liquid crystal display device according to claim 3, wherein the second insulating film comprises an organic resin.

5. The active matrix liquid crystal display device according to claim 3, wherein the second insulating film comprises a siloxane-based polymer.

6. An active matrix EL display device comprising:

a thin film transistor formed over a substrate, the thin film transistor comprising;

a gate electrode;

a gate insulating film formed over the gate electrode; and

a semiconductor film comprising a metal oxide wherein the metal oxide is In—

Ga—

Zn—

O;

a first inorganic insulating film formed on the semiconductor film;

a second insulating film having a planarized upper surface formed over the first inorganic insulating film; and

a pixel electrode formed over the second insulating film and electrically connected to the thin film transistor.

7. The active matrix EL display device according to claim 6, wherein the second insulating film comprises an organic resin.

8. The active matrix EL display device according to claim 6, wherein the second insulating film comprises a siloxane-based polymer.