Novel SAW Temperature Sensor with Pt/Ti/AlN/Mo/AlN/Si Structure for High Temperature Application
Yong Ruan,
Yang Chen,
Yu Wu,
Meng Shi,
Yan Du,
Zhiqiang Song,
Yiyang Chen,
Helei Dong,
Congchun Zhang,
Jiao Teng
Affiliations
Yong Ruan
Department of Precision Instruments, Tsinghua University, Beijing 100084, China
Yang Chen
Department of Materials Physics and Chemistry, University of Science and Technology Beijing, Beijing 100083, China
Yu Wu
Department of Precision Instruments, Tsinghua University, Beijing 100084, China
Meng Shi
MEMS Institute of Zibo National High-Tech Industrial Development Zone, Zibo 255000, China
Yan Du
MEMS Institute of Zibo National High-Tech Industrial Development Zone, Zibo 255000, China
Zhiqiang Song
MEMS Institute of Zibo National High-Tech Industrial Development Zone, Zibo 255000, China
Yiyang Chen
Department of Precision Instruments, Tsinghua University, Beijing 100084, China
Helei Dong
State Key Laboratory of Dynamic Measurement Technology, North University of China, Taiyuan 030051, China
Congchun Zhang
National Key Laboratory of Science and Technology on Micro/Nano Fabrication, School of Electronics Information and Electrical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China
Jiao Teng
Department of Materials Physics and Chemistry, University of Science and Technology Beijing, Beijing 100083, China
In this paper, a surface acoustic wave (SAW) temperature sensor with a Pt/Ti/AlN/Mo/AlN/Si structure was prepared, and the high temperature characteristics of the sensors at 20–600 °C under different electrode metallization rates (ղ) were measured. It was found that frequent device mutation occurred in the first high-temperature test, and that the mutation point decreased with the increase in the electrode metallization rate (ղ). In the subsequent test, the data became stable, the sensor’s center frequency increased, the return loss (S11) decreased and the factor of merit (Q) increased. After annealing the same sensors at 600 °C for 30 min, they could achieve performance improvement in the first test, meaning that proper annealing can improve sensor performance. In addition, the annealed SAW sensor was tested in the temperature range of 20–1000 °C, which met the requirement of a temperature range of 20–900 °C, its f–T curve was linear, the factor of merit (Q) was 34.5 and the sensitivity was 46.6 KHz/K.
