In-situ monitoring of thickness of quartz membrane during batch chemical etching using a novel micromackined acoustic wave sensor
| Autor: | Ping-Hei Chen, Kaihsiang Yen, Fu-Yuan Xiao, Chi-Yuan Lee, Ching-Liang Dai, Lung-Jieh Yang, Yung-Yu Chen, Tsung-Tsong Wu, Chih-Kung Lee, Shih-Yung Pao, Shui-Shong Lu, Pei-Zen Chang, Chih-Wei Liu, Wen-Jong Chen, Ying-Chou Cheng |
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| Rok vydání: | 2004 |
| Předmět: |
Materials science
business.industry Acoustics Surface acoustic wave technology industry and agriculture Acoustic wave Quartz crystal microbalance respiratory system complex mixtures Isotropic etching Resonator Membrane otorhinolaryngologic diseases Optoelectronics Surface acoustic wave sensor business Quartz |
| Zdroj: | IEEE International Frequency Control Sympposium and PDA Exhibition Jointly with the 17th European Frequency and Time Forum, 2003. Proceedings of the 2003. |
| Popis: | This work presents a novel method based on the surface acoustic wave (SAW) device for monitoring in-situ the thickness of quartz membrane during batch chemical etching. Similar to oscillators and resonators, some SAW devices require the thickness of quartz membranes to be known precisely. Precisely controlling the thickness of a quartz membrane during batch chemical etching is important, because it strongly influences post-processing and frequency control. Furthermore, the proposed micromachined acoustic wave sensor, allows the thickness of a quartz membrane from a few /spl mu/m to hundreds of /spl mu/m to be monitored in-situ. In particular, the proposed method is highly appropriate for monitoring in-situ a few /spl mu/m thick quartz membranes, because the thickness of a quartz membrane is proportional to the phase velocity. In summary, the proposed method for measuring the thickness of quartz membrane in real time, has high accuracy, is simple to set up and can be mass produced. Also described herein are the principles of the method used, the detailed process flows, the measurement set-up and the simulation and experimental results. The theoretical and measured values differ by an error of less than 2 /spl mu/m, so the results agreed with each other closely. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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