Skip to main content
Improved Sensitivity MEMS Cantilever Sensor for Terahertz Photoacoustic Spectroscopy
  • Ronald A. Coutu, Jr.
  • Ivan Medvedev, Wright State University - Main Campus
  • Douglas T. Petkie, Wright State University - Main Campus
Document Type
Publication Date
In this paper, a microelectromechanical system (MEMS) cantilever sensor was designed, modeled and fabricated to measure the terahertz (THz) radiation induced photoacoustic (PA) response of gases under low vacuum conditions. This work vastly improves cantilever sensitivity over previous efforts, by reducing internal beam stresses, minimizing out of plane beam curvature and optimizing beam damping. In addition, fabrication yield was improved by approximately 50% by filleting the cantilever’s anchor and free end to help reduce high stress areas that occurred during device fabrication and processing. All of the cantilever sensors were fabricated using silicon-on-insulator (SOI) wafers and tested in a custom built, low-volume, vacuum chamber. The resulting cantilever sensors exhibited improved signal to noise ratios, sensitivities and normalized noise equivalent absorption (NNEA) coefficients of approximately 4.28 × 10−10 cm−1·WHz−1/2. This reported NNEA represents approximately a 70% improvement over previously fabricated and tested SOI cantilever sensors for THz PA spectroscopy.

This is an open access article distributed under the Creative Commons Attribution License (CC BY) which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Citation Information
Ronald A. Coutu, Ivan Medvedev and Douglas T. Petkie. "Improved Sensitivity MEMS Cantilever Sensor for Terahertz Photoacoustic Spectroscopy" Sensors Vol. 16 Iss. 2 (2016) ISSN: 14248220
Available at: