In this work we report finite element method simulation, design and fabrication process of an uncooled thermal infrared detector with high-sensitivity. The device is based on the differential association of thermocouples (Cu/constantan), shaped appropriately in order to increase the thermoelements density, deposited onto silicon substrates to provide further integration with silicon technology. The Si substrate is back-side etched with Deep Reactive-Ion Etching (DRIE), creating regions with different thickness under each thermoelement in order to improve the thermal gradient. On the wafer front side, a constantan serpentine is potentiostatically electrodeposited following the parameters obtained from reference 1. Thermocouples are formed by plating copper pad upon the constantan layer. The device is covered by a porous gold layer (black–gold), prepared byevaporating in inert atmosphere, that works as an efficient absorber in the far infrared spectral region [2]. The major advantages expected from the micromachined sensor are the small dimensions, low power consumption, low cost, high sensitivity, good accuracy and resolution in the far infrared spectra. The application of this sensor could be in the demand of on-line monitoring for thermal confort, in heat transfer control for industrial processes and for CCD far infrared cameras.
Far infrared microsensor based on transversal gradients
Guarnieri, Vittorio;Lorenzelli, Leandro;
2010-01-01
Abstract
In this work we report finite element method simulation, design and fabrication process of an uncooled thermal infrared detector with high-sensitivity. The device is based on the differential association of thermocouples (Cu/constantan), shaped appropriately in order to increase the thermoelements density, deposited onto silicon substrates to provide further integration with silicon technology. The Si substrate is back-side etched with Deep Reactive-Ion Etching (DRIE), creating regions with different thickness under each thermoelement in order to improve the thermal gradient. On the wafer front side, a constantan serpentine is potentiostatically electrodeposited following the parameters obtained from reference 1. Thermocouples are formed by plating copper pad upon the constantan layer. The device is covered by a porous gold layer (black–gold), prepared byevaporating in inert atmosphere, that works as an efficient absorber in the far infrared spectral region [2]. The major advantages expected from the micromachined sensor are the small dimensions, low power consumption, low cost, high sensitivity, good accuracy and resolution in the far infrared spectra. The application of this sensor could be in the demand of on-line monitoring for thermal confort, in heat transfer control for industrial processes and for CCD far infrared cameras.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
