Design and simulation of a coplanar capacitive sensor for non-destructive thin-film dielectric measurement



  • Nguyen Anh Dung Hanoi University of Industry
  • Nguyen Dac Nam Phenikaa University
  • Nguyen Viet Hoang Hanoi University of Industry
  • Nguyen Cao Minh Hanoi University of Industry
  • Dong Minh Hoang Hanoi University of Industry
  • Nguyen Dac Hai (Corresponding Author) Hanoi University of Industry



Capacitive sensor; Coplanar sensor; Non-contact thin-film thickness measurement; Non-destructive thin-film thickness measurement.


 This article presents a different design of coplanar capacitive sensors for application in non-destructive thin film dielectric measurement with high performance and minimal cost. Another difference in this sensor design is that to reduce parasitic components and common noise, the capacitive sensor structure is designed to include a reference capacitor and a sensing capacitor. Using this structure, the dielectric of the thin film can be estimated through the unbalanced capacitance generated between the two signals from the reference capacitor and the sensing capacitor. Two electrode structures were researched, simulated, and the interdigital structure with the highest performance was selected. Simulations were conducted using a Polyethylene (PE) thin film with dielectric varying from 1.375 to 3.19 and a thickness of 40 µm to study the working principle of the sensor. Simulation results show the linearity of the sensor's output capacitance corresponding to different dielectrics. The sensitivity of the sensor is 20.86 fF/1 dielectric unit and 178.96 fF/1 dielectric unit for thin films with thicknesses of 10 µm and 120 µm, respectively. Simulation results demonstrate that this sensor has high potential for application in dielectric measurement of thin films for military and biomedical applications.


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How to Cite

Nguyễn Anh, D., N. Nguyễn Đắc, H. Nguyễn Việt, M. Nguyễn Cao, H. Đồng Minh, and H. Nguyễn Đắc. “Design and Simulation of a Coplanar Capacitive Sensor for Non-Destructive Thin-Film Dielectric Measurement”. Journal of Military Science and Technology, vol. 93, no. 93, Feb. 2024, pp. 55-62, doi:10.54939/1859-1043.j.mst.93.2024.55-62.



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