Mechanical modeling and characterization of suspended cooled silicon bolometers for sub-millimeter and millimeter waves polarization detection
Autor: | A. Aliane, W. Rabaud, O.-A. Adami, R. Torrecillas, P. Agnese, L. Rodriguez, H. Kaya, J-L. Ouvrier-Buffet, Albrecht Poglitsch, Laurent Dussopt, V. Reveret, V. Goudon |
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Přispěvatelé: | Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information (CEA-LETI), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Max-Planck-Institut für Extraterrestrische Physik (MPE) |
Rok vydání: | 2019 |
Předmět: |
Materials science
Cantilever Passivation Silicon chemistry.chemical_element 02 engineering and technology 01 natural sciences law.invention Stress (mechanics) [SPI]Engineering Sciences [physics] law Residual stress 0103 physical sciences Electrical and Electronic Engineering Composite material Instrumentation Noise-equivalent power 010302 applied physics Bolometer Metals and Alloys 021001 nanoscience & nanotechnology Condensed Matter Physics Polarization (waves) Surfaces Coatings and Films Electronic Optical and Magnetic Materials chemistry 0210 nano-technology |
Zdroj: | Sensors and Actuators A: Physical Sensors and Actuators A: Physical, Elsevier, 2019, 296, pp.254-264. ⟨10.1016/j.sna.2019.07.024⟩ Sensors and Actuators A: Physical, 2019, 296, pp.254-264. ⟨10.1016/j.sna.2019.07.024⟩ |
ISSN: | 0924-4247 1873-3069 |
Popis: | Silicon bolometers for space and astronomy applications, fabricated in standard CMOS-SOI technology are now successfully used as cryogenic detectors working at very low temperature, typically in the range of 0.05–0.1 K. They feature a remarkably high electromagnetic absorption, high temperature sensitivity and low noise. However, the mechanical behavior of suspended silicon bolometers results from the fabrication process parameters and a good understanding of these mechanisms is necessary to better control their deformation. In this work, silicon bolometer pixels with a pitch of 1200 μm and 500 μm for millimeter-wave (mm-wave) polarization detection have been fabricated and their mechanical behavior is investigated at room temperature and cryogenic temperature. First, a mechanical model was developed based on simulated and experimental deformations at room temperature of multi-layer cantilever test structures with different Young’s modulus and thickness (Ei, hi). The actual multi-layer suspended structures are modeled as an equivalent composite layer with an effective Young’s modulus (Eeff), an effective thickness (heff) and residual stresses (σ0, σ1). The residual stress values are positive, corresponding to a tensile stress in the fabricated multilayer stack. The impact of the a-Si passivation thickness on the total stress is discussed. The equivalent model is used in the simulation of the full pixel structure and results in excellent agreement with optical measurements of the deflection at room temperature. At cryogenic temperatures, mechanical deformations can hardly be measured, so the mechanical behavior of a 500-μm pixel was simulated at 0.1 K assuming that tensile residual stresses coming from defects are independent on temperature, and a good mechanical stability of the pixel was obtained. The optical performance simulation of this 500-μm pixel is discussed and showed that the mechanical deformations result in a degradation of the Noise Equivalent Power (NEP) from 1.59 × 10−18 to 1.05 × 10-17 W/Hz1/2 for an optical load of 6 × 10−15 W at 0.1 K. |
Databáze: | OpenAIRE |
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