Thin film metal resistors can be integrated into microchips for resistive heating and temperature sensing purposes. Localized heating of fluids is accomplished by placing the heating resistors in between glass layers close to a channel. In order to determine the temperature the resistance of a known resistor is measured. The resistance of platinum films scales nearly linearly over a wide temperature range, which simplifies the calibration of the sensor. When using a 4-point resistance measurement method the resistance of the connecting leads is eliminated and very precise and localized temperature sensing is feasible. The combination of electrical heaters and temperature sensors on a chip provides a convenient means to warm fluids inside microchannels to the desired temperature.

Metal resistors can be integrated in almost any glass chip on the surface or in between layers. Integration of resistors in silicon chips is done on request.

Specifications
Below the specifications of thin film resistors are given.