The temperature dependence of the resonance frequency of quartz resonators can be used for thermal infrared sensors. The quartz chips must be very thin to obtain a good sensor signal. This work describes how to manufacture and package sensors with 5 µm thin chips. Different sensor layouts are ion beam etched; they influence the vibration of the resonators, which is shown by impedance measurements. The temperature coefficient of the resonance frequency is determined to be around 90 ppm K^-1.

We have managed to reduce the measuring time of previously common hydrogel-based sensors from a few minutes to a few seconds. For this, the arrangement of the hydrogel in the sensor was changed so that the volume of the hydrogel could be reduced. The biggest challenge, apart from generating a very thin pattern, was to firmly bond the hydrogel to a silicon surface. This was to ensure that the resulting forces of the bimorph effect can be absorbed.