1. Field of the Invention
The present invention relates to a light emitting device formed by building a semiconductor element (element using a semiconductor thin film) onto a substrate using a light emitting element that has a film (hereafter referred to as an “organic compound layer”) containing an organic compound in which fluorescence or phosphorescence is obtained by the application of an electric field, typically an EL (electro luminescence) display device. In addition, the present invention relates to electronic equipment that uses an EL display device as a display (display portion). Note that light emitting devices are also referred to as OLEDs (organic light emitting diodes).
Note that the term “light emitting element” in this specification indicates elements in which an organic compound layer is formed between a pair of electrodes. The term “light emitting device” indicates image display devices using light emitting elements or light emitting devices. Further, modules in which a connector, for example, an anisotropic conductive film (flexible printed circuit. FPC), a TAB (tape automated bonding) tape, or a TCP (tape carrier package) is attached to light emitting elements, modules in which the tip of the TAB tape or TCP is provided with a printed wiring board, and modules in which an IC (integrated circuit) is directly mounted to light emitting elements by a COG (chip on glass) method are all included in the category of light emitting devices.
2. Description of the Related Art
The development of light emitting devices (EL display devices) using EL elements as light emitting elements that utilize EL (electro luminescence) phenomenon of light emitting organic materials has recently been advancing. This is because it is considered that the EL display devices have a wider angle of view and superior visibility, compared to conventional liquid crystal display devices.
Further, there are two types of EL display devices, a passive type (simple matrix type) and an active type (active matrix type), and the development of both the types is flourishing. In particular, active matrix EL display devices are in the spotlight at present. Furthermore, organic compound materials which become EL layers (strictly speaking, light emitting layers), the EL element center, can be divided into low molecular weight organic compound materials and high molecular weight (polymer) organic compound materials, and both the materials are being researched.
Ink jet printing, evaporation, and spin coating methods are known as methods of forming a film of these organic compound materials.
However, when considering the manufacture of a full color flat panel display with the use of red, green, and blue light emission colors, none of the aforementioned film formation methods can be called ideal for a variety of reasons and this has been a problem for low cost, large-scale production.
USPTO Backgrounds
USPTO Backgrounds