One of the most exciting opportunities in optoelectronics currently is devices based on organic materials. These have many advantages, primarily: lower-technology processing with less sensitivity to processing environment (but many are very air sensitive), flexibility, and the opportunity to apply the enormous power of organic synthesis to tailoring the properties of the materials to specific applications. Furthermore, organics can emit light directly as do conventional cathode-ray-tubes and plasma display panels, rather than relying on back-lighting systems such as are used in liquid-crystal displays. One can imagine these technologies leading to poster-sized televisions which can be rolled up and stored in mailing tubes, or unrolled and thumb-tacked to a wall. The materials are already being applied in compact lightweight, power-efficient light emitting devices in small areas such as cell-phone displays. The primary problem with all organic devices is stability. When carriers are injected into these materials, sometimes a molecule falls apart. This does not need to be very common for the device to degrade significantly over relatively short operating times. This chapter considers the options for organic semiconductors and how they are applied.
KeywordsHigh Occupied Molecular Orbital Lower Unoccupied Molecular Orbital Organic Semiconductor Charge Injection Lower Unoccupied Molecular Orbital Energy
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