Light-emitting device

• US 20090114926A1
• Filed: 05/12/2008
• Published: 05/07/2009
• Est. Priority Date: 05/18/2007
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yamazaki, Shunpei
• Granted Patent: US 8,513,678 B2
• Time in Patent Office: Days
• US Class Current: 257/79
• CPC Class Codes: G09G 3/3208 organic, e.g. using organic light-emitting diodes [OLED]
• CPC Class Codes: H01L 27/12 the substrate being other than a semiconductor body, e.g. an insulating body
• 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: 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: H01L 29/66772 Monocristalline silicon transistors on insulating substrates, e.g. quartz substrates H01L29/66666 takes precedence; thin film FinFETs H01L29/66795
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 33/02 characterised by the semiconductor bodies
• CPC Class Codes: H10K 59/38 comprising colour filters or colour changing media [CCM]

Abstract

A light-emitting device includes a pixel having a transistor provided over a substrate, and a light-emitting element. The transistor includes a single-crystal semiconductor layer which forms a channel formation region, a silicon oxide layer is provided between the substrate and the single-crystal semiconductor layer, a source or a drain of the transistor is electrically connected to an electrode of the light-emitting element, and the transistor is operated in a saturation region when the light-emitting element emits light. Further, in the light-emitting device, a gray scale of the light-emitting element is displayed by changing a potential applied to the gate of the transistor.

Claims

1. A light-emitting device comprising:

a substrate;

a pixel comprising;

a transistor comprising a semiconductor layer comprising a channel formation region; and

a pixel electrode of a light-emitting element, electrically connected to the semiconductor layer; and

a driver circuit configured to operate the transistor in a saturation region when the light-emitting element emits light,

wherein the semiconductor layer is a single-crystal semiconductor layer provided over the substrate with a silicon oxide layer provided therebetween.

2. The light-emitting device according to claim 1, wherein the driver circuit is further configured to change a potential applied to a gate electrode of the transistor according to a gray scale signal.

3. The light-emitting device according to claim 1, wherein the single-crystal semiconductor layer is provided by separating from a single-crystal semiconductor substrate.

4. The light-emitting device according to claim 1, the pixel further comprises a nitrogen-containing layer provided between the silicon oxide layer and the single-crystal semiconductor layer.

5. The light-emitting device according to claim 1, wherein the silicon oxide layer is provided by a chemical vapor deposition method using an organosilane as a source gas

6. The light-emitting device according to claim 1, wherein the substrate is a glass substrate.

7. The light-emitting device according to claim 1, wherein the semiconductor layer comprise a halogen element.

9. The light-emitting device according to claim 7, wherein the pixel further comprises a capacitor electrically connected between the second gate electrode and the power supply line.

8. A light-emitting device comprising:

a substrate;

a scanning line provided over the substrate;

a signal line provided over the substrate;

a power supply line provided over the substrate;

a pixel comprising;

a first transistor comprising;

a first semiconductor layer comprising a first channel formation region, electrically connected to the signal line; and

a first gate electrode electrically connected to the scanning line;

a second transistor comprising;

a second semiconductor layer comprising a second channel formation region, electrically connected to the power supply line; and

a second gate electrode electrically connected to the first semiconductor layer; and

a pixel electrode of a light-emitting element, electrically connected to the second semiconductor layer, and

a driver circuit configured to operate the second transistor in a saturation region when the light-emitting element emits light,

wherein both of the first semiconductor layer and the second semiconductor layer are single-crystal semiconductor layers provided over the substrate with a silicon oxide layer provided therebetween.

10. The light-emitting device according to claim 8, wherein the driver circuit is configured to change a potential applied to the second gate electrode according to a gray scale signal.

11. The light-emitting device according to claim 8, wherein the single-crystal semiconductor layers are provided by separating from a single-crystal semiconductor substrate.

12. The light-emitting device according to claim 8, the pixel further comprises a nitrogen-containing layer provided between the silicon oxide layer and the single-crystal semiconductor layers.

13. The light-emitting device according to claim 8, wherein the silicon oxide layer is provided by a chemical vapor deposition method using an organosilane as a source gas

14. The light-emitting device according to claim 8, wherein the substrate is a glass substrate.

15. The light-emitting device according to claim 8, wherein the first semiconductor layer comprise a halogen element.

16. A light-emitting device comprising:

a substrate;

a first scanning line provided over the substrate;

a second scanning line provided over the substrate;

a signal line provided over the substrate;

a power supply line provided over the substrate;

a pixel comprising;

a first transistor comprising;

a first semiconductor layer comprising a first channel formation region, electrically connected to the signal line; and

a first gate electrode electrically connected to the first scanning line;

a second transistor comprising;

a second semiconductor layer comprising a second channel formation region, electrically connected to the power supply line; and

a second gate electrode electrically connected to the first semiconductor layer;

a third transistor comprising;

a third semiconductor layer comprising a third channel formation region, electrically connected between the power supply line and the second gate electrode; and

a third gate electrode electrically connected to the second scanning line; and

a pixel electrode of a light-emitting element, electrically connected to the second semiconductor layer, and

a driver circuit configured to operate the second transistor in a saturation region when the light-emitting element emits light,

wherein all of the first semiconductor layer, the second semiconductor layer and the third semiconductor layer are single-crystal semiconductor layers provided over the substrate with a silicon oxide layer provided therebetween.

17. The light-emitting device according to claim 16, wherein the pixel further comprises a capacitor electrically connected between the second gate electrode and the power supply line.

18. The light-emitting device according to claim 16, wherein the driver circuit is configured to change a potential applied to the second gate electrode according to a gray scale signal.

19. The light-emitting device according to claim 16, wherein the single-crystal semiconductor layers are provided by separating from a single-crystal semiconductor substrate.

20. The light-emitting device according to claim 16, the pixel further comprises a nitrogen-containing layer provided between the silicon oxide layer and the single-crystal semiconductor layers.

21. The light-emitting device according to claim 16, wherein the silicon oxide layer is provided by a chemical vapor deposition method using an organosilane as a source gas

22. The light-emitting device according to claim 16, wherein the substrate is a glass substrate.

23. The light-emitting device according to claim 16, wherein the first semiconductor layer comprise a halogen element.

24. A method for manufacturing a light-emitting device comprising the steps of:

forming a separation layer in a single-crystal silicon substrate, by irradiating an ion;

bonding the single-crystal silicon substrate to a substrate having an insulating surface, after the step of forming the separation layer;

forming a single-crystal silicon layer by separating single-crystal silicon layer from the separation layer;

forming a thin film transistor comprising an active layer formed from the single-crystal silicon layer;

forming a pixel electrode of a light-emitting element electrically connected to the active layer; and

forming a driver circuit configured to operate the transistor in a saturation region when the light-emitting element emits light.