Microcavity plasma UV lamps: Efficient VUV, UV-C and UV-B generation with flat form factor

Summary form only given. Flat lamps have been developed which comprise large arrays of microcavity plasmas, and they are capable of efficiently generating UV light in the range of VUV to UV-B. UV light is desirable for a number of chemical processes and disinfection methods and lamps are available commercially, but conventional UV light sources suffer from several drawbacks, including undesirable form factors and environmental concerns regarding the use of mercury. Microplasmas are non-equilibrium, low temperature plasma sources which have high power loading (several hundred kW/cm3), thereby enabling them to efficiently form UV-generating excimer molecules. Additionally, they contain no toxic substances such as mercury. This work has focused on leveraging microplasma array technology to realize low temperature UV lamps that are flat and designed to have a scalable, slim form-factor (total thickness less than ~6 mm). Each microcavity (less than a few millimeters in its cross-sectional dimensions) was fabricated on a quartz window substrate by microfabrication techniques, and the spatial variation of the electric field strength in each microcavity was tailored through the cavity cross-section and electrode geometry to reduce power consumption and to efficiently generate deep UV radiation. UV light tiles have been fabricated which are capable of producing fluences up to 200 mW/cm
²
at 172 nm which generates more than 10 watts of average power from a lamp of only 16 inches square (100 cm
²
) in surface area. Details concerning lamp performance and the design of several UV lamps having emitting wavelengths specifically at 172, 222, and 308 nm will be discussed.