In October 1999, Eastman Kodak and Sanyo Electric jointly announced the development of a high quality, 2.4 inch diagonal Full Color active matrix Organic Light Emitting Diode (OLED) display. This technology demonstration resulted from the successful integration of Kodak's organic electroluminescence display technology and Sanyo's low temperature polysilicon TFT technology. Commercial samples are expected to reach the market in 2001. The active matrix OLED displays feature a wider viewing angle and a faster response speed than conventional LCDs. With its low power consumption, high brightness and thin design, these OLED displays when incorporated in digital cameras, personal digital assistants (PDA), videophones and other portable imaging devices, will offer a superior value proposition to consumer electronics products. Several OLED display designs are under development now to serve various market segments. This paper will summarize the status of active matrix full color OLED display development, the key technical challenges, and the path ahead.

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Intermixing of AlGaAs-based interfaces is known to be enhanced by capping wafers with a layer of SiO2. Assuming that this enhancement results from the introduction of additional Ga vacancies into the sample, it is possible to obtain the temperature-dependent equilibrium Ga vacancy diffusivity. Experiments are performed whereby SiO2-capped quantum well samples are annealed at temperatures ranging from 800 to 1025 °C. Calculated photoluminescence shifts are compared with the measured spectra, and a relation for the Ga vacancy diffusivity of the form 0.962 exp(−2.72/kBT) cm2/s is obtained. Using this relation, the equilibrium Ga vacancy concentration can be computed via an ensemble Monte Carlo simulation. The resulting expression is 1.25×1031 exp(−3.28/kBT) cm−3.

Mass production of full-color active-matrix OLED (AMOLED) displays began in October 2002 at SK Display Corporation. This milestone was achieved through an integration of modified lowtemperature polysilicon substrates (LTPS), manufacturing subsystems for the uniform deposition of OLED device structures, encapsulation subsystems with automated desiccant delivery, precision shadow masks for color pixel patterning, and the ability to meet product specifications. This paper discusses the advances made in process integration, reproducibility of display performance, productivity gains, and yield improvement. During two years of production experience, SK Display has made steady progress on its manufacturing learning curve and has already introduced secondgeneration AMOLED production equipment for 335 x 550 mm glass substrates. The chosen OLED technologies are scaleable to larger glass substrate sizes compatible with existing LTPS facilities. Even though OLED deposition technologies have significantly matured in productivity, yield, and available capacity, substantial improvements in the quality of LTPS substrates suitable for OLEDs is necessary before AMOLEDs can become competitive with AMLCDs.