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Title: Thermoelectric infrared microsensors based on a periodically suspended thermopile integrating nanostructured Ge/SiGe quantum dots superlattice

This paper presents an original integration of polycrystalline SiGe-based quantum dots superlattices (QDSL) into Thermoelectric (TE) planar infrared microsensors (μSIR) fabricated using a CMOS technology. The nanostructuration in QDSL results into a considerably reduced thermal conductivity by a factor up to 10 compared to the one of standard polysilicon layers that are usually used for IR sensor applications. A presentation of several TE layers, QDSL and polysilicon, is given before to describe the fabrication of the thermopile-based sensors. The theoretical values of the sensitivity to irradiance of μSIR can be predicted thanks to an analytical model. These findings are used to interpret the experimental measurements versus the nature of the TE layer exploited in the devices. The use of nanostructured QDSL as the main material in μSIR thermopile has brought a sensitivity improvement of about 28% consistent with theoretical predictions. The impact of QDSL low thermal conductivity is damped by the contribution of the thermal conductivity of all the other sub-layers that build up the device.
Authors:
; ; ; ;  [1] ; ; ;  [2]
  1. IEMN, Institute of Electronics, Microelectronics and Nanotechnology, CNRS and Lille 1 University, F-59652 Villeneuve d'Ascq (France)
  2. CEA, LITEN, Thermoelectricity Laboratory, F-38054 Grenoble (France)
Publication Date:
OSTI Identifier:
22308528
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 116; Journal Issue: 4; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; EQUIPMENT; GERMANIUM; GERMANIUM SILICIDES; INFRARED RADIATION; LAYERS; PERIODICITY; POLYCRYSTALS; QUANTUM DOTS; RADIANT FLUX DENSITY; SENSITIVITY; SENSORS; SUPERLATTICES; THERMAL CONDUCTIVITY; THERMOCOUPLES; THERMOELECTRIC PROPERTIES