French National Centre for Scientific Research (CNRS), Laboratory for Analysis and Architecture of Systems (LAAS), University of Toulouse, Institut National Polytechnique de Toulouse (INPT), 7 Avenue du Colonel Roche, 31031 Toulouse, France.
Université Paris-Saclay, CEA, Service d'Etude du Comportement des Radionucléides, 91191 Gif-sur-Yvette, France.
Sensors (Basel). 2021 Sep 2;21(17):5912. doi: 10.3390/s21175912.
This paper reports the design, fabrication and measured performance of a passive microelectromechanical transducer for the wireless monitoring of high irradiation doses in nuclear environments. The sensing device is composed of a polymer material (high-density polyethylene) sealed inside a cavity. Subjected to ionizing radiation, this material releases various gases, which increases the pressure inside the cavity and deflects a dielectric membrane. From the measurement of the deflection, the variation of the applied pressure can be estimated, and, in turn, the dose may be determined. The microelectromechanical structure can also be used to study and validate the radiolysis properties of the polymer through its gas emission yield factor. Measurement of the dielectric membrane deflection is performed here to validate on the one hand the required airtightness of the cavity exposed to doses about 4 MGy and on the other hand, the functionality of the fabricated dosimeter for doses up to 80 kGy. The selection of appropriate materials for the microelectromechanical device is discussed, and the outgassing properties of the selected high-density polyethylene are analysed. Moreover, the technological fabrication process of the transducer is detailed.
本文报告了一种用于核环境中无线监测高辐照剂量的无源微机电换能器的设计、制造和测量性能。该传感装置由密封在腔体内的聚合物材料（高密度聚乙烯）组成。在电离辐射的作用下，这种材料会释放出各种气体，从而增加腔体内的压力并使介电膜发生偏移。通过测量这种偏移量，可以估算出所施加压力的变化，进而确定剂量。通过测量气体发射产额因子，微机电结构还可以用于研究和验证聚合物的辐射分解特性。本文通过测量介电膜的偏移量，一方面验证了暴露在约 4MGy 剂量下的腔体所需的密封性能，另一方面验证了所制造的剂量计在高达 80kGy 剂量下的功能。此外，还讨论了微机电装置的合适材料选择，并分析了所选高密度聚乙烯的出气特性。详细介绍了换能器的工艺制造过程。
