BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a light-emitting device manufactured by using an element (light-emitting element) that emits light by applying a current between electrodes with a luminescent material therebetween, and more particularly, relates to a sealing structure in the light-emitting device.

2. Description of the Related Art

In recent years, thin and light displays using light-emitting elements have been actively developed. In order to manufacture a light-emitting element, a material that produces luminescence by applying a current is interposed between a pair of electrodes. Since the light-emitting element itself emits light unlike a liquid crystal, a light source such as a backlight is not necessary, and thus, the element itself is quite thin. Accordingly, the light-emitting element is quite advantageous when thin and light displays are manufactured.

However, one of the backgrounds to the fact that no practical application has been achieved in spite of having these great advantages is a problem of reliability. A light-emitting element using an organic material is often deteriorated due to moisture (water), and has the disadvantage that it is hard to obtain reliability for a long period of time. The light-emitting element deteriorated due to water causes decrease in luminance or emits no light any longer. This is considered to be a cause for a dark spot (black spot) or luminance degradation from the periphery of a light-emitting device (luminance degradation in which a light-emitting area gradually decreases from an edge portion of a display device, which is hereinafter referred to as “periphery deterioration”) in a light-emitting device using a light-emitting element, and various measures has been proposed in order to suppress this deterioration (for example, refer Patent Documents 1 and 2).

However, even if these measures are applied, sufficient reliability has not been obtained yet, and further improvement in reliability has been desired.

In addition, for a light-emitting device, it is often the case that an organic insulating film that can be formed by coating is used as an insulating film. This organic insulating film has properties that are quite favorable in applying to a light-emitting device, such as superiority in flatness and capability to reduce unevenness of the underlying layer.

Patent Document 1:

Japanese Patent Application Laid-Open No. 9-148066

Patent Document 2:

Japanese Patent Application Laid-Open No. 7-169567

SUMMARY OF THE INVENTION

The organic insulating film has the properties, which are quite favorable when a light-emitting device is formed. However, in the case of a light-emitting device that has an interlayer insulating film formed with the use of an organic insulating film, periphery deterioration can be accelerated depending on the structure thereof.

Consequently, it is an object of the present invention to provide a light-emitting device where deterioration at the periphery can be prevented from occurring even when an organic insulating film is used as an insulating film for the light-emitting device. In addition, it is an object of the present invention to provide a light-emitting device where reliability for a long period of time can be improved.

One of structures of a light-emitting device according to the present invention for solving the problem includes a first substrate; a first insulating film comprising organic material, formed over the first substrate; a film comprising inorganic material formed on the first organic insulating film; a second insulating film covering an edge of the film comprising inorganic material, formed over the first insulating film; a light emitting element having at least one electrode, a portion of the electrode formed on the second insulating film; and a second substrate opposed to the first substrate with a sealing material interposed therebetween, wherein the sealing material is formed on a portion of the film comprising inorganic material, wherein the film comprising inorganic material is not overlapped with the electrode, and wherein there is a gap between the sealing material and the electrode.

One of the structures of the light-emitting device according to the present invention for solving the problem includes a first substrate; a first insulating film comprising organic material, formed over the first substrate; first and second films formed on the first organic insulating film, each of the first and second films comprising inorganic material; a second insulating film comprising organic material, covering the second film and comprising inorganic material and an edge of the first film comprising inorganic material, formed over the first insulating film; a light emitting element having at least one electrode, a portion of the electrode formed on the second insulating film; and a second substrate opposed to the first substrate with a sealing material interposed therebetween, wherein the sealing material is formed on a portion of the first film comprising inorganic material, wherein a portion of the second film comprising inorganic material is overlapped with the electrode, and wherein there are a gap between the first film comprising inorganic material and the second film comprising inorganic material and a gap between the sealing material and the electrode.

One of the structures of the light-emitting device according to the present invention for solving the problem includes a first substrate; a first insulating film comprising organic material, formed over the first substrate; at least first and second films formed on the first insulating film, each of the first and second films comprising inorganic material; a second insulating film comprising organic material, covering an edge of the first film comprising inorganic material and an edge of the second film comprising inorganic material, formed over the first insulating film; a light emitting element having at least one electrode, a portion of the electrode formed on the second insulating film; and a second substrate opposed to the first substrate with a sealing material interposed therebetween, wherein each of the first film comprising inorganic material and second film comprising inorganic material has a portion of less than 1 mm in width between an edge of the first substrate and the electrode, and wherein there is a gap between the sealing material and the electrode.

One of the structures of the light-emitting device according to the present invention for solving the problem includes a first substrate; a first insulating film comprising organic material, formed over the first substrate; at least first and second films formed on the first insulating film, each of the first and second films comprising inorganic material; a second insulating film comprising organic material, covering an edge of the first film comprising inorganic material and an edge of the second film comprising inorganic material, formed over the first insulating film; a light emitting element having at least one electrode, a portion of the electrode formed on the second insulating film; and a second substrate opposed to the first substrate with a sealing material interposed therebetween, wherein each of the first film comprising inorganic material and second inorganic film comprising inorganic material has a portion of less than 1 mm in width between an edge of the first substrate and the electrode, and

wherein the sealing material is overlapped with the electrode and the overlap is 15 μm or less.

One of the structures of the light-emitting device according to the present invention for solving the problem includes a first substrate; a first insulating film comprising organic material, formed over the first substrate; at least first and second films adjacent to each other formed on the first insulating film, each of the first and second films comprising inorganic material; a second insulating film comprising organic material, covering an edge of the first film comprising inorganic material and an edge of the second film comprising inorganic material, formed over the first insulating film; a light emitting element having at least one electrode, a portion of the electrode formed on the second insulating film; and a second substrate opposed to the first substrate with a sealing material interposed therebetween, wherein each of the first and second films has a portion of less than 1 mm in width, wherein a distance between the first film comprising inorganic material and second film comprising inorganic material is 5 μm or more, and wherein there is a gap between the sealing material and the electrode.

One of the structures of the light-emitting device according to the present invention for solving the problem includes a first substrate; a first insulating film comprising organic material, formed over the first substrate; at least first and second films adjacent to each other formed on the first insulating film, each of the first and second films comprising inorganic material; a second insulating film comprising organic material, covering an edge of the first film comprising inorganic material and an edge of the second film comprising inorganic material, formed over the first insulating film; a light emitting element having at least one electrode, a portion of the electrode formed on the second insulating film; and a second substrate opposed to the first substrate with a sealing material interposed therebetween, wherein each of the first film comprising inorganic material and second film comprising inorganic material has a portion of less than 1 mm in width, wherein a distance between the first film comprising inorganic material and second film comprising inorganic material is 5 or more, and wherein the sealing material is overlapped with the electrode and the overlap is 15 μm or less.

One of the structures of the light-emitting device according to the present invention for solving the problem includes a first substrate; a first insulating film comprising organic material, formed over the first substrate; a film comprising inorganic material formed on the first insulating film; a second insulating film comprising organic material, covering an edge of the film comprising inorganic material, formed over the first insulating film; a light emitting element having at least one electrode, a portion of the electrode formed on the second insulating film; and a second substrate opposed to the first substrate with a sealing material interposed therebetween, wherein the film comprising inorganic material has at least first and second openings at least between an edge of the first substrate and the electrode, wherein the first and second openings are arranged adjacent to each other in a narrower-side direction of the first and second openings, wherein each width of the first and second opening is 5 μm or more in the shorter-side direction of the first and second openings, wherein a distance between the first and second openings is less than 1 mm, and wherein there is a gap between the sealing material and the electrode.

One of the structures of the light-emitting device according to the present invention for solving the problem includes a first substrate; a first insulating film comprising organic material, formed over the first substrate; a film comprising inorganic material formed on the first insulating film; a second insulating film comprising organic material, covering an edge of the film comprising inorganic material, formed over the first insulating film; a light emitting element having at least one electrode, a portion of the electrode formed on the second insulating film; and a second substrate opposed to the first substrate with a sealing material interposed therebetween, wherein the film comprising inorganic material has at least first and second openings at least between an edge of the first substrate and the electrode, wherein the first and second openings are arranged adjacent to each other in a narrower-side direction of the first and second openings, wherein each width of the first and second opening is 5 μm or more in the shorter-side direction of the first and second openings, wherein a distance between the first and second openings is less than 1 mm, and wherein the sealing material is overlapped with the electrode and the overlap is 15 μm or less.

The present invention can be applied to not only a light emitting device but also a semiconductor device. One of the structures of a semiconductor device according to the present invention for solving the problem includes a first substrate; a first insulating film comprising organic material, formed over the first substrate; a film comprising inorganic material formed on the first organic insulating film; a second insulating film covering an edge of the film comprising inorganic material, formed over the first insulating film; an electrode, a portion of the electrode formed on the second insulating film; and a second substrate opposed to the first substrate with a sealing material interposed therebetween, wherein the sealing material is formed on a portion of the film comprising inorganic material, wherein the film comprising inorganic material is not overlapped with the electrode, and wherein there is a gap between the sealing material and the electrode.

In addition, there are not so many wirings dragged from the outside of or from under a sealing material close to an upper electrode for a light-emitting element in the case of an actual active matrix panel. However, such a structure can be required to be formed, and deterioration occurs naturally from that part. The commercial value of a light-emitting device in which a periphery portion is not lighted due to deterioration is dramatically decreased even though the portion is just a part of the light-emitting device. Therefore, the structure according to the present invention can be preferably used also as a measure for a small portion at the periphery of a light-emitting element.

The light-emitting device according to the present invention, which has the structure described above, is a light-emitting device where periphery deterioration can be prevented from occurring even when an organic insulating film is used as an insulating film, and is also a light-emitting device where reliability for a long period of time can be improved.

