Sensor stack for Tian-Calvet Calorimeter made in LTCC-Technology
Abstract The paper presents the construction and first tests of a new sensor stack for a Tian-Calvet Calorimeter made in LTCC Technology. In contrast to typical construction where wired thermocouples are directly connected, the here-presented solution replaces wired thermocouples by screen-printed thick-film thermocouples placed on a structured disc made of Low Temperature Co-fired Ceramics (LTCC). The advantage of screen-printed thermocouples is the ease of integration of them into thick-film hybrid structures, and to simplify the device setup. Moreover, using thermocouples integrated into a ceramic disc can increase the sensitivity of the system and simultaneously reduce the production costs. The paper shows the design and fabrication of the sensor stacks. It consists of several LTCC discs and ceramic spacers. On each LTCC disc, 34 Au/Pt thermocouples were deposited. The design of the disc was supported by FEM-modelling under consideration of device specific requirements. The very initial measurements, which we conducted using two sensor stacks already exhibited a sensitivity of 8 μV/mW, which is more than satisfactory in this stage of development.