Thermal characterisation of μL volumes using a thin film thermocouple based sensor

摘要: Abstract A microfabricated sensor capable of measuring the thermal conductivity small samples is presented. Thin film thermocouples and a resistive heater were fabricated on polyimide substrate, to form hot-wire-like sensor. Microfabrication allowed manufacture sensors, with current devices formed 20 μm line widths 75 μm separations between sensors. thin layer used encapsulate device, without degrading sensitivity. This gives advantages flexibility, robustness, electrical isolation, chemical resistance biocompatibility. The operation was demonstrated by 100 μL droplets glycerin/water mixtures. Additionally, 2-propanol/water mixtures tested derive dependence concentration mixture, as this not available in literature. subsequently monitor time varying properties smaller volumes non-liquid samples. Wetted paper used, due its thickness (∼100 μm) relatively slow change it dries. It found that decreases dries out detected devices. Furthermore, theoretical experimental drying times sheet investigated exhibit similar air temperature. provided clear evidence for device's ability volumes.