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Development of Low-Temperature ITO Process for Flat Panel Display P. M. Martin(a) and G. L. Graff (a) Supported by DARPA. (a) EMSL User. The interest in flat-panel display technologies has been ever increasing over the last decade, driven by the huge market value. Small organic molecule- and polymer-based emission (OLED) are considered the most promising FPD technologies because of their high brightness, easy color tuning, and great potential for fabrication on large, flexible, lightweight, and low-cost polymer substrates. OLED devices apply thin organic layers sandwiched between two electrodes. Light is emitted as a result of fluorescent decay of the excited singlet created by recombination of opposite charges injected from the electrodes. Indium-tin oxide (ITO) offers high optical transparency, low electrical resistivity, and easy patterning. These properties make ITO the preferred transparent electrode for display applications. The sputter deposition chamber in the thin film deposition laboratory was used to deposit ITO films at low temperature on polymer substrates. The deposition was conducted using a ceramic ITO target (In90%:Sn10%) and Ar/O2 mixture. The optical transmission and electrical resistivity of the deposited ITO films were obtained using UV/Vis spectroscopy and four-point probe measurements. The results were correlated with and used to optimize the deposition parameters. Through these efforts, a very robust low-temperature ITO deposition process was achieved. Today, ITO films with resistivity below 5.0 x 10-4 W cm and optical transmission higher than 85% in the visible range can be readily obtained. The films have been evaluated separately by several major display companies and proven to be among the best ITO films deposited at low temperatures. William R. Wiley Environmental Molecular Sciences Laboratory Feedback: webmaster@emsl.pnl.gov Revised: June 12, 2001 Security & Privacy PNNL-13147