Semiconductor device having display portion with plural pixels

• US 8,907,559 B2
• Filed: 03/06/2014
• Issued: 12/09/2014
• Est. Priority Date: 06/05/2000
• Status: Expired due to Fees

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yamazaki, Shunpei
• Primary Examiner(s): Guharay, Karabi
• Application Number:
  US14/198,852
• Publication Number:
  US 20140183542A1
• Time in Patent Office: 278 Days
• Field of Search: 313/504, 313/506, 313/509
• US Class Current: 313/504
• CPC Class Codes: H01L 27/1214 comprising a plurality of TFTs formed on a non-semiconducting substrate, e.g. driving circuits for AMLCDs
• CPC Class Codes: H10K 2101/10 Triplet emission
• CPC Class Codes: H10K 2102/00 Constructional details relating to the organic devices covered by this subclass
• CPC Class Codes: H10K 50/11 characterised by the electroluminescent [EL] layers
• CPC Class Codes: H10K 50/828 Transparent cathodes, e.g. comprising thin metal layers
• CPC Class Codes: H10K 59/12 Active-matrix OLED [AMOLED] displays
• CPC Class Codes: H10K 59/1213 the pixel elements being TFTs
• CPC Class Codes: H10K 59/122 Pixel-defining structures or layers, e.g. banks
• CPC Class Codes: H10K 59/123 Connection of the pixel electrodes to the thin film transistors [TFT]
• CPC Class Codes: H10K 59/35 comprising red-green-blue [RGB] subpixels
• CPC Class Codes: H10K 85/30 Coordination compounds
• CPC Class Codes: H10K 85/342 comprising iridium
• CPC Class Codes: H10K 85/346 comprising platinum
• CPC Class Codes: Y10S 428/917 Electroluminescent

Abstract

There is provided a light emitting device which enables a color display with good color balance. A triplet compound is used for a light emitting layer of an EL element that emits red color, and a singlet compound is used for a light emitting layer of an EL element that emits green color and a light emitting layer of an EL element that emits blue color. Thus, an operation voltage of the EL element emitting red color may be made the same as the EL element emitting green color and the EL element emitting blue color. Accordingly, the color display with good color balance can be realized.

Claims

1. A semiconductor device comprising:

a display portion over a first substrate, the display portion comprising a first pixel and a second pixel,

wherein each of the first pixel and the second pixel comprises;

a transistor comprising a gate electrode, a gate insulating layer, a semiconductor layer, a source electrode, and a drain electrode;

an interlayer insulating film over the transistor;

a pixel electrode over the interlayer insulating film, the pixel electrode being electrically connected to one of the source electrode and the drain electrode;

a first insulating layer over the interlayer insulating film, the first insulating layer covering an edge portion of the pixel electrode;

an electroluminescent layer over the pixel electrode and the first insulating layer, the electroluminescent layer comprising a light-emitting layer;

a cathode over the electroluminescent layer,

wherein the electroluminescent layer in the first pixel includes iridium, and

wherein the electroluminescent layer in the second pixel comprises a fluorescent material.

2. The semiconductor device according to claim 1, further comprising a second insulating layer over the cathode.

3. The semiconductor device according to claim 1, wherein the first pixel and the second pixel are red emissive and blue emissive, respectively.

4. The semiconductor device according to claim 1, wherein the pixel electrode and the cathode are configured so that light emitted in the light-emitting layer is extracted through the cathode.

5. The semiconductor device according to claim 1, wherein the first insulating layer has a taper shape.

6. The semiconductor device according to claim 1, further comprising a second substrate over the cathode,

wherein the first substrate and the second substrate are bonded to each other with a first sealant and a second sealant,

wherein the second sealant is located outside the first sealant and in contact with a side surface of the first substrate and a side surface of the second substrate.

7. The semiconductor device according to claim 6, further comprising:

a wiring over the first substrate, the wiring being covered by the first sealant; and

a flexible printed circuit connected to the wiring.

8. An electronic device comprising the semiconductor device according to claim 1, wherein the display portion is configured to modulate luminance in accordance with brightness of environment of use.

9. An electronic device comprising:

a housing equipped with a charge coupled device and the semiconductor device according to claim 1.

10. A semiconductor device comprising:

a display portion over a first substrate, the display portion comprising a first pixel and a second pixel,

wherein each of the first pixel and the second pixel comprises;

a semiconductor layer;

a gate electrode over the semiconductor layer;

a source electrode and a drain electrode connected to the semiconductor layer;

a pixel electrode connected to one of the source electrode and the drain electrode;

a first insulating layer covering an edge portion of the pixel electrode;

an electroluminescent layer over the pixel electrode and the first insulating layer, the electroluminescent layer comprising a light-emitting layer; and

a cathode over the electroluminescent layer,

wherein the electroluminescent layer in the first pixel includes iridium, and

wherein the electroluminescent layer in the second pixel comprises a fluorescent material.

11. The semiconductor device according to claim 10, further comprising a second insulating layer over the cathode.

12. The semiconductor device according to claim 10, wherein the first pixel and the second pixel are red emissive and blue emissive, respectively.

13. The semiconductor device according to claim 10, wherein the pixel electrode and the cathode are configured so that light emitted in the light-emitting layer is extracted through the cathode.

14. The semiconductor device according to claim 10, wherein the first insulating layer has a taper shape.

15. The semiconductor device according to claim 10, further comprising a second substrate over the cathode,

wherein the first substrate and the second substrate are bonded to each other with a first sealant and a second sealant,

wherein the second sealant is located outside the first sealant and in contact with a side surface of the first substrate and a side surface of the second substrate.

16. The semiconductor device according to claim 15, further comprising:

a wiring over the first substrate, the wiring being covered by the first sealant; and

a flexible printed circuit connected to the wiring.

17. An electronic device comprising the semiconductor device according to claim 10, wherein the display portion is configured to modulate luminance in accordance with brightness of environment of use.

18. An electronic device comprising:

a housing equipped with a charge coupled device and the semiconductor device according to claim 10.