Self-Supporting Ultrathin DLC/Si3N4/SiO2 for Micro-Pressure Sensor
At a Glance
Section titled “At a Glance”| Metadata | Details |
|---|---|
| Publication Date | 2021-12-08 |
| Journal | IEEE Sensors Journal |
| Authors | Xin Ma, Qi Zhang, Peng Guo, Hao Li, Yulong Zhao |
| Institutions | Xi’an Jiaotong University, Ningbo Institute of Industrial Technology |
| Citations | 7 |
Abstract
Section titled “Abstract”In this study, we firstly reported a micro-pressure sensor based on self-supporting diamond-like carbon (DLC)/Si <sub xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”>3</sub> N <sub xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”>4</sub> /SiO <sub xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”>2</sub> films with total thickness of 785 nm, where the DLC film was fabricated by a facile DC magnetron sputtering process. Particularly, the DLC film was selected as a hybrid sensitive and structural material due to its superior mechanical, piezoresistive properties and stability under harsh environment. Results showed that the sensitivity of the integrated sensor could reach <inline-formula xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”> <tex-math notation=“LaTeX”>$5.3,,\times10$ </tex-math></inline-formula> <sup xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”>-5</sup> /kPa within the pressure range of 0-60 kPa, together with the nonlinearity and the hysteresis was 5.7% FS (full scale) and 0.8% FS, respectively (at 20 °C). Most importantly, without any thermal insulation package, the sensitivity only changed slightly within ±7.0% even the temperature varied dramatically from −20 °C to 100 °C. Such excellent performance of the sensor was mainly originated from the good stability of atomic bond structure in DLC films, which was confirmed by the variable-temperature XPS test. In addition, the signal could be further compensated by the DLC thermal compensation resistor in which the temperature coefficient of resistance (TCR) was about −1247.3 ppm/°C. These results bring forward a promising strategy to fabricate the micro-pressure sensor with high structural sensitivity, stability as well as lightweight design for micro-electromechanical system (MEMS) used in harsh applications.