Flexible Al/Al/sub 2/O/sub 3/SIO/sub 2/ microplasma arrays: large area ultraviolet source for biomedical applications

Summary form only given. Flexible planar light sources are becoming a key technology for several applications such as portable displays, flexible illumination sources and biomedical applications. In particular, ultraviolet emission wavelengths between 250 and 400 nm are of great importance in biomedical applications. In this presentation, we report the fabrication and characteristics of arrays of microplasma devices having Al₂O₃ encapsulated metal electrodes which are designed for operation at atmospheric gas pressure. Following the growth of a thin layer of nanostructured Al₂O₃ on Al foil by a multistep electrochemical process, a film of SiO₂ is deposited to bring the total dielectric thickness to 5 mum. Because the overall thickness of the device structure is 60-100 mum, an array of devices is fully flexible and is readily scalable in surface area. When driven by a sinusoidal waveform having a frequency of 20 kHz, the operating voltage for 600 torr of Ne is nominally 200 V (RMS). Also, the variation in emission intensity across the array is less than 10%. Several wavelength regions in the UV are accessible through the choice of molecular emitters. The optical and electrical characteristics of large scale arrays (tens of cm²) that are vacuum-sealed and flexible will be described