1. Field of the Invention
The present invention relates to a flat panel display and a method of manufacturing the same, and more particularly, to a flat panel display which provides improved flexibility by using a metal substrate or a conductive substrate which is protected from exposure to ambient conditions. Also presented is a method of manufacturing the flat panel display.
2. Description of the Related Technology
Typical flat panel displays, such as, organic electroluminescent displays, TFT-LCDs, etc., can be thin and flexible. Hence, much research into flat panel displays has been performed to improve flexibility and thinness.
To be thin and flexible, flat panel displays use a flexible substrate. The flexible substrate is generally made of synthetic resin. Flat panel displays include various elements, such as, an organic film, a thin film transistor, electrodes, or an orientation film. These elements are formed under various process conditions. When the flexible substrate is made of synthetic resin, the process may result in the flexible substrate being deformed or in a thin film formed on the substrate being deformed.
To overcome this problem, a technique of forming a flexible substrate of metal foil instead of synthetic resin is under study.
This metal foil substrate is suitable for top-emission type flat panel displays in which light generated in a display unit is emitted in a direction away from the flexible substrate. In addition, a metal foil substrate is less sensitive to the process conditions than a conventional substrate. For example, the metal foil substrate can relatively freely undergo a high-temperature process for crystallizing amorphous silicon into polycrystalline silicon without suffering damage. U.S. Patent Publication No. 2004/0,087,066 discloses an active matrix (AM) organic electroluminescent display using a metal foil substrate.
Since the metal foil substrate is an electrical conductor, the metal foil substrate should not be exposed to the environment after final assembly of the display device. The surface of the metal foil substrate opposite to where the display unit is formed can be prevented from being exposed by being covered with an insulator. However, in mass production, many display devices are simultaneously manufactured by forming many display units on a single metal substrate and then cutting the metal substrate. Although the metal substrate is covered with an insulator beforehand, the cutting process exposes portions of the metal substrate around the periphery of the display. Because of these exposed portions, static electricity affects the display units, thus degrading the quality and durability of the display devices.