[1] Zhang ZiliYin ChenboTao ChunminZhu Bin,. Characteristics of suspended planar-type gas sensorbased on MEMS process [J]. Journal of Southeast University (English Edition), 2012, 28 (3): 315-320. [doi:10.3969/j.issn.1003-7985.2012.03.011]
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Characteristics of suspended planar-type gas sensorbased on MEMS process(
)
)Journal of Southeast University (English Edition)[ISSN:1003-7985/CN:32-1325/N]
- Volumn:
- 28
- Issue:
- 2012 3
- Page:
- 315-320
- Research Field:
- Automation
- Publishing date:
- 2012-09-30
Info
- Title:
- Characteristics of suspended planar-type gas sensorbased on MEMS process
- Author(s):
- Zhang ZiliYin ChenboTao ChunminZhu Bin
- School of Mechanical and Power Engineering, Nanjing University of Technology, Nanjing 210009, China
- PACS:
- TP212.2
- DOI:
- 10.3969/j.issn.1003-7985.2012.03.011
- Abstract:
- In order to simplify the fabrication process, distribute the temperature uniformly and reduce the power consumption of the micro-hotplate(MHP)gas sensor, a planar-type gas sensor based on SnO2 thin film with suspended structure is designed through a MEMS process. Steady-state thermal analysis of the gas sensor and the closed membrane type sensor where the membrane overlaps the Si substrate is carried out with the finite element model, and it is shown that the suspended planar-type gas sensor has a more homogeneous temperature distribution and a lower power consumption. When the maximum temperature on the sensor reaches 383℃, the power consumption is only 7 mW, and the temperature gradient across the thin film is less than 14℃. To overcome the fragility of the suspended beams, a novel fabrication process in which the deposition of the gas sensing film occurs prior to the formation of suspended beams is proposed. The back side of the Si substrate is etched through deep reactive ion etching(DRIE)to avoid chemical pollution of the front side. The fabrication steps in which only four masks are used for the photolithography are described in detail. The Fe doped SnO2 thin film synthesized by sol-gel spin-coating is used as the gas sensing element. The device is tested on hydrogen and exhibits satisfactory sensing performance. The sensitivity increases with the rise of the concentration from 50×10-6 to 2000×10-6, and reaches about 30 at 2000×10-6.
References:
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Memo
- Memo:
-
Biographies: Zhang Zili(1984—), male, graduate; Yin Chenbo(corresponding author), male, doctor, professor, yinchenbo@njut.edu.cn.
Foundation items: The National Natural Science Foundation of China(No.58175122), the Natural Science Foundation of Jiangsu Province(No.BK2007185), the Natural Science Foundation of Higher Education Institutions of Jiangsu Province(No.07KJB460044), the Scientific Research Innovation Project for College Graduates in Jiangsu Province(No.CXZZ11_0340).
Citation: Zhang Zili, Yin Chenbo, Tao Chunmin, et al. Characteristics of suspended planar-type gas sensor based on MEMS process[J].Journal of Southeast University(English Edition), 2012, 28(3):315-320.[doi:10.3969/j.issn.1003-7985.2012.03.011]