Light-emitting device and electronic device
A highly reliable light-emitting device is provided. Damage to an element due to externally applied physical power is suppressed. Alternatively, in a process of pressure-bonding of an FPC, damage to a resin and a wiring which are in contact with a flexible substrate due to heat is suppressed. A neutral plane at which stress-strain is not generated when a flexible light-emitting device including an organic EL element is deformed, is positioned in the vicinity of a transistor and the organic EL element. Alternatively, the hardness of the outermost surface of a light-emitting device is high. Alternatively, a substrate having a coefficient of thermal expansion of 10 ppm/K or lower is used as a substrate that overlaps with a terminal portion connected to an FPC.
1. A light-emitting device comprising:
a first flexible substrate comprising a first surface and a second surface opposite to and below the first surface;
a transistor over the first surface;
a planarization layer over the transistor;
a light-emitting element over the planarization layer, the light-emitting element being electrically connected to the transistor;
an adhesive layer over the light-emitting element; and
a second flexible substrate over the adhesive layer, the second flexible substrate comprising a third surface and a fourth surface opposite to and over the third surface,
wherein the adhesive layer is in contact with the third surface, and
wherein a first distance from the second surface to a top surface of the planarization layer is 0.8 to 1.2 times as large as a second distance from the fourth surface to the top surface of the planarization layer.
2. The light-emitting device according to claim 1 ,
wherein the first distance is 0.9 to 1.1 times as large as the second distance.
3. The light-emitting device according to claim 1 ,
wherein the planarization layer is in contact with the transistor.
4. The light-emitting device according to claim 1 ,
wherein the light-emitting element comprises a layer containing a light-emitting organic compound between a pair of electrodes, and
wherein the light-emitting element is in contact with the planarization layer.
5. An electronic device comprising the light-emitting device according to claim 4 in a display portion.
6. An electronic device comprising the light-emitting device according to claim 1 in a display portion.
7. The light-emitting device according to claim 1 ,
wherein the adhesive layer is in contact with the planarization layer.
8. The light-emitting device according to claim 1 ,
wherein a portion of one of the transistor, the planarization layer, and the light-emitting element is positioned in a neutral plane.
9. A light-emitting device comprising:
a first flexible substrate comprising a first surface and a second surface opposite to and below the first surface;
a transistor over the first surface;
a planarization layer over the transistor;
a light-emitting element over the planarization layer, the light-emitting element being electrically connected to the transistor;
a first protection layer covering the light-emitting element;
a second protection layer over the first protection layer;
an adhesive layer over the light-emitting element; and
a second flexible substrate over the adhesive layer, the second flexible substrate comprising a third surface and a fourth surface opposite to and over the third surface,
wherein a thickness of the first protection layer is greater than or equal to 0.1 μm and less than 100 μm,
wherein a surface of the second protection layer has a higher hardness than a surface of the first protection layer,
wherein the adhesive layer is in contact with the third surface, and
wherein a first distance from the second surface to a top surface of the planarization layer is 0.8 to 1.2 times as large as a second distance from the fourth surface to the top surface of the planarization layer.
10. The light-emitting device according to claim 9 ,
wherein the first distance is 0.9 to 1.1 times as large as the second distance.
11. An electronic device comprising the light-emitting device according to claim 9 in a display portion.
12. The light-emitting device according to claim 9 ,
wherein the adhesive layer is in contact with the planarization layer.
13. The light-emitting device according to claim 9 ,
wherein a portion of one of the transistor, the planarization layer, and the light-emitting element is positioned in a neutral plane.
14. A light-emitting device comprising:
a first flexible substrate comprising a first surface and a second surface opposite to and below the first surface;
a transistor over the first surface;
a planarization layer over the transistor;
a light-emitting element over the planarization layer, the light-emitting element being electrically connected to the transistor;
an adhesive layer over the light-emitting element;
a second flexible substrate over the adhesive layer, the second flexible substrate comprising a third surface and a fourth surface opposite to and over the third surface; and
an FPC affixed to the first substrate,
wherein the adhesive layer is in contact with the third surface, and
wherein a first distance from the second surface to a top surface of the planarization layer is 0.8 to 1.2 times as large as a second distance from the fourth surface to the top surface of the planarization layer.
15. The light-emitting device according to claim 14 ,
wherein the first distance is 0.9 to 1.1 times as large as the second distance.
16. The light-emitting device according to claim 14 ,
wherein the planarization layer is in contact with the transistor.
17. The light-emitting device according to claim 14 ,
wherein the light-emitting element comprises a layer containing a light-emitting organic compound between a pair of electrodes, and
wherein the light-emitting element is in contact with the planarization layer.
18. An electronic device comprising the light-emitting device according to claim 14 in a display portion.