Fabrication and characterization of LTCC-based millinewton force sensor: influence of design and materials compatibility on device performance
LTCC (low temperature co-fired ceramic) technology has recently gained a remarkable application potential in sensors field. This can be ascribed to many advantages it offers: the ease of LTCC tape handling providing a great freedom in design and fabrication, feasible processing conditions bringing down the costs, excellent thermal and chemical resistance, and combination of electrical and mechanical functions in a reliable hermetic system. In scope of this, fabrication of an LTCC-based millinewton force sensor is introduced in this paper. Processing steps, design and electrical performance of the sensor is explained in details. The results are compared to the previously-fabricated sensor that is based on alumina. It is shown that the sensitivity of the sensor is significantly improved in the first attempts, by replacing the alumina beam with LTCC. In a separate section, LTCC-materials incompatibility issues and their effects on the sensitivity of the sensor are discussed. The tools of the study are SEM (scanning electron microscopy), dilatometry and electronics for characterization of the sensor.