Flexible light-emitting device, and method for fabricating the same

• US 8,284,369 B2
• Filed: 08/11/2009
• Issued: 10/09/2012
• Est. Priority Date: 08/20/2008
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Hatano, Kaoru, Nagata, Takaaki, Seo, Satoshi, Chida, Akihiro
• Primary Examiner(s): Qi, Mike
• Application Number:
  US12/538,975
• Publication Number:
  US 20100045919A1
• Time in Patent Office: 1,155 Days
• Field of Search: 349/149, 362/278, 438/30, 257/E33.061
• US Class Current: 349/149
• CPC Class Codes: H01L 27/1225 with semiconductor materials not belonging to the group IV of the periodic table, e.g. InGaZnO
• CPC Class Codes: H01L 27/124 with a particular composition, shape or layout of the wiring layers specially adapted to the circuit arrangement, e.g. scanning lines in LCD pixel circuits wiring structures per se H01L23/52
• CPC Class Codes: H01L 27/1248 with a particular composition or shape of the interlayer dielectric specially adapted to the circuit arrangement
• CPC Class Codes: H01L 27/1266 the substrate on which the devices are formed not being the final device substrate, e.g. using a temporary substrate
• CPC Class Codes: H10K 2102/311 Flexible OLED
• CPC Class Codes: H10K 59/12 Active-matrix OLED [AMOLED] displays
• CPC Class Codes: H10K 59/1201 Manufacture or treatment
• CPC Class Codes: H10K 59/123 Connection of the pixel electrodes to the thin film transistors [TFT]
• CPC Class Codes: H10K 59/131 Interconnections, e.g. wiring lines or terminals
• CPC Class Codes: H10K 71/00 Manufacture or treatment specially adapted for the organic devices covered by this subclass
• CPC Class Codes: H10K 71/80 using temporary substrates

Abstract

Provided is a flexible light-emitting device including: a base insulating film; a thin film transistor formed over a first surface of the base insulating film; an interlayer insulating film formed over the first surface of the base insulating film with the thin film transistor interposed therebetween; a first pixel electrode formed on a second surface of the base insulating film opposite to the first surface; an electroluminescent layer formed on the second surface of the base insulating film with the first pixel electrode interposed therebetween; a second pixel electrode formed on the second surface of the base insulating film with the first pixel electrode and the electroluminescent layer interposed therebetween; and a wiring electrically connected to a semiconductor layer of the thin film transistor in a contact hole provided in the interlayer insulating film and electrically connected to the first pixel electrode in a through-hole penetrating through at least the interlayer insulating film and the base insulating film.

Claims

1. A flexible light-emitting device comprising:

a base insulating film;

a thin film transistor formed over a first surface of the base insulating film;

an interlayer insulating film formed over the first surface of the base insulating film with the thin film transistor interposed therebetween;

a first pixel electrode formed under a second surface of the base insulating film opposite to the first surface;

an electroluminescent layer formed under the second surface of the base insulating film with the first pixel electrode interposed therebetween;

a second pixel electrode formed under the second surface of the base insulating film with the first pixel electrode and the electroluminescent layer interposed therebetween; and

a wiring which is electrically connected to a semiconductor layer of the thin film transistor in a contact hole provided in the interlayer insulating film and is electrically connected to the first pixel electrode in a through-hole penetrating through at least the interlayer insulating film and the base insulating film.

2. The flexible light-emitting device according to claim 1, wherein the first pixel electrode projects with respect to the second surface of the base insulating film.

3. The flexible light-emitting device according to claim 1, further comprising:

a first adhesive layer formed over the first surface of the base insulating film with the thin film transistor, the interlayer insulating film, and the wiring interposed therebetween; and

a first flexible substrate formed over the first surface of the base insulating film with the thin film transistor, the interlayer insulating film, the wiring, and the first adhesive layer interposed therebetween.

4. The flexible light-emitting device according to claim 1, further comprising:

a second adhesive layer formed under the second surface of the base insulating film with the first pixel electrode, the electroluminescent layer, and the second pixel electrode interposed therebetween; and

a second flexible substrate formed under the second surface of the base insulating film with the first pixel electrode, the electroluminescent layer, the second pixel electrode, and the second adhesive layer interposed therebetween.

5. A method for fabricating a flexible light-emitting device comprising:

forming a separation layer over a formation substrate;

forming a base insulating film over the separation layer;

forming an island-like crystalline semiconductor layer over the base insulating film;

forming a gate insulating film over the crystalline semiconductor layer;

forming a gate electrode over the gate insulating film which overlaps with the crystalline semiconductor layer;

forming an interlayer insulating film over the gate electrode and the gate insulating film;

forming a contact hole which penetrates through at least the interlayer insulating film and the gate insulating film and reaches the crystalline semiconductor layer, and a through-hole which penetrates through at least the interlayer insulating film, the gate insulating film, and the base insulating film and reaches the separation layer;

forming a wiring which is electrically connected to the crystalline semiconductor layer in the contact hole and reaches at least the separation layer in the through-hole;

bonding a flexible substrate onto the wiring and the interlayer insulating film;

separating the base insulating film provided with the flexible substrate from the formation substrate;

forming a first pixel electrode which is in contact with the base insulating film exposed by the separation and is electrically connected to the wiring;

forming a partition wall covering an end portion of the first pixel electrode;

forming an electroluminescent layer in contact with at least the first pixel electrode; and

forming a second pixel electrode in contact with at least the electroluminescent layer.

6. A method for fabricating a flexible light-emitting device comprising:

forming a separation layer over a formation substrate;

forming a base insulating film over the separation layer;

forming an island-like crystalline semiconductor layer over the base insulating film;

forming a gate insulating film over the crystalline semiconductor layer;

forming a gate electrode over the gate insulating film which overlaps with the crystalline semiconductor layer;

forming an interlayer insulating film over the gate electrode and the gate insulating film;

forming a contact hole which penetrates through at least the interlayer insulating film and the gate insulating film and reaches the crystalline semiconductor layer, and a through-hole which penetrates through at least the interlayer insulating film, the gate insulating film, and the base insulating film and reaches the separation layer;

forming a wiring which is electrically connected to the crystalline semiconductor layer in the contact hole and reaches at least the separation layer in the through-hole;

bonding a flexible substrate onto the wiring and the interlayer insulating film;

separating the base insulating film provided with the flexible substrate from the formation substrate;

forming a partition wall which is in contact with the base insulating film exposed by the separation and has an opening so as to expose at least the through-hole;

disposing a conductive substance with fluidity in the opening of the partition wall to form a first pixel electrode;

forming an electroluminescent layer in contact with at least the first pixel electrode; and

forming a second pixel electrode in contact with at least the electroluminescent layer.

7. A method for fabricating a flexible light-emitting device comprising:

forming a separation layer over a formation substrate;

forming a base insulating film over the separation layer;

forming an island-like crystalline semiconductor layer over the base insulating film;

forming a gate insulating film over the crystalline semiconductor layer;

forming a gate electrode over the gate insulating film which overlaps with the crystalline semiconductor layer;

forming an interlayer insulating film over the gate electrode and the gate insulating film;

forming a contact hole which penetrates through at least the interlayer insulating film and the gate insulating film and reaches the crystalline semiconductor layer;

forming a wiring which is electrically connected to the crystalline semiconductor layer in the contact hole;

bonding a flexible substrate onto the wiring and the interlayer insulating film;

separating the base insulating film provided with the flexible substrate from the formation substrate;

irradiating the flexible substrate with a laser beam to form a through-hole which penetrates through at least the base insulating film, the gate insulating film, the interlayer insulating film, the wiring, and the flexible substrate;

forming a connection wiring which is electrically connected to the wiring in the through-hole;

forming a first pixel electrode which is in contact with the base insulating film exposed by the separation and is electrically connected to the connection wiring;

forming a partition wall covering an end portion of the first pixel electrode;

forming an electroluminescent layer in contact with at least the first pixel electrode; and

forming a second pixel electrode in contact with at least the electroluminescent layer.