In most MEMS applications, dust and particles are avoided with considerable endeavor. However, for many applications such as gas sensors, powders of functional ceramics would often provide better performance than corresponding thin film layers. There are abundant ways to synthesize powders with well defined chemical composition, phase and size distribution, whereas the processing parameters for thin-film preparation often are limited. Specifically where the functionality is based on a chemical reaction on surfaces, nanoscaled powders with a high specific surface area have proven useful. This is the case for tin oxide gas sensors that exhibit a drop in electrical resistivity induced by the combustion of the analyte gas. Soft lithography was used for the fabrication of mesoscaled powder-based ceramic structures. In this paper, we present the integration of small tin oxide microstructures with an effective gas-sensing area of 10 by 30 νm2 on a micro-hotplate substrate. Such a substrate can heat the ceramic sensor to operating temperatures quickly with low power consumption. A whole array of sensors can be integrated on one micro-hotplate. Processing steps to prepare the sensor array on the micro hot plate are presented and discussed concerning processing sequence, sensitivity towards 1000 to 1500 ppm hydrogen and power consumption. Additionally, effects of grain growth due to on-chip annealing of the ceramic nanostructure were observed.