Micropatterned Heater for Multiplexed Nanoplasmonic Sensing

Abstract

In order to utilise nanoplasmonic sensing for air quality measurements, the temperature of the sensing layer must be controlled. This is possible through the use of a microheater localised on the sensor, which trough Joule heating can make it possible to manage the sensor’s temperature with high accuracy. However, the microheater’s design can determine both energy efficiency and the sensing properties of the sensor, hence careful design and characterisation of the micropatterned heater must take place in order to optimise it. Further more, for multiplexed sensing where several air pollutants are measured simultaneously, the microheater must be able to maintain several distinct temperatures on the same sensor. In this thesis, several sensors with new geometries have been modelled and fabricated, both for the purpose of multiplexing and to yield lower power consumption. By using thermoresistive measurements on the microheaters, it was determined that it was possible to decrease the power consumption up to 51% by lowering the sensor thickness and decreasing the size of the heated region. Through the use of thermal imaging, it was also confirmed that the temperature uniformity of the heated region could be increased by introducing a laser cut groove or gap around it. For the multiplexing sensors, which were designed to be able to sense at least four different gases, heating one distinct region to 120 C resulted in the remaining sensing areas to reach temperatures of 30-43 C.