Procedia Engineering · 2014 · 17 citations · 2 references
EngineeringElectrical EngineeringMaterials ScienceMicroelectronicsSemiconductor DevicesSensorsMems SensorsMicroelectromechanical SensorsSemiconductor Device MaterialsTemperature MeasurementTemperature SensorsThermal SensorsDeep Reactive Ion EtchingInfrared Temperature SensorsInfrared ThermometryMems Thermal SensorsReactive Ion EtchingSeebeck CoefficientSemiconductor Temperature SensorsSingle-crystal Silicon
In this paper, we describe an infrared thermopile sensor comprising of single crystal silicon p+ and n+ elements, with an integrated diode temperature sensor fabricated using a commercial SOI-CMOS process followed by Deep Reactive Ion Etching (DRIE). The chip area is 1.16 mm × 1.06 mm. The integrated diode, being on the same substrate, allows a more localized measurement of the cold junction temperature compared to a conventional external thermistor. The use of single crystal silicon allows good process control and reproducibility from device-to-device in terms of both Seebeck coefficient and sensor resistance. The device has a measured responsivity of 23 V/W, detectivity of 0.75 × 108 cm√Hz/W, a 50% modulation depth of 60 Hz and shows enhanced responsivity in the 8 – 14 μm wavelength range, making it particularly suitable for thermometry applications.
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