On-Chip Cooling Thermal Flow Sensor for Biological Applications

A novel on-chip cooling thermal flow sensor is realized: We fabricated an integrated calorimetric and a hot-film thermal flow sensor with a cooling thermal reference using a Peltier module to create a thermal distribution depending on the flow rate. The integrated thermal flow sensors realize high-resolution and wide-range flow-rate measurement in a microfluidic device without heating reagents. Due to the non-heating characteristic, the proposed thermal flow sensor can avoid heat denaturation of biological reagents, such as blood and cell-containing samples, and allows us to use a higher resolution flow sensor in biological analysis.