Performance enhance of CMOS-MEMS thermoelectric infrared sensor by using sensing material and structure design

This study describes the fabrication of an ammonia gas sensor (AGS) using a complementary metal oxide semiconductor (CMOS)–microelectromechanical system (MEMS) technique. The structure of the AGS features interdigitated electrodes (IDEs) and a sensing material on a silicon substrate. The IDEs are the stacked aluminum layers that are made using the CMOS process. The sensing material; polypyrrole/reduced graphene oxide (PPy/RGO), is synthesized using the oxidation–reduction method; and the material is characterized using an electron spectroscope for chemical analysis (ESCA), a scanning electron microscope (SEM), and high-resolution X-ray diffraction (XRD). After the CMOS process; the AGS needs post-processing to etch an oxide layer and to deposit the sensing material. The resistance of the AGS changes when it is exposed to ammonia. A non-inverting amplifier circuit converts the resistance of the AGS into a voltage signal. The AGS operates at room temperature. Experiments show that the AGS response is 4.5% at a concentration of 1 ppm NH3; and it exhibits good repeatability. The lowest concentration that the AGS can detect is 0.1 ppm NH3

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A novel elevating structure design applied on the motion behavior analysis of micro optical devices by CMOS-MEMS process

10.1117/12.645027 ◽

2006 ◽

Author(s):

Chien-Chung Tsai ◽

Zhen-Hao Fan ◽

Pei-Hao Lin

Keyword(s):

Behavior Analysis ◽

Optical Devices ◽

Structure Design ◽

Cmos Mems ◽

Mems Process ◽

Motion Behavior

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A double-end-beam based infrared device fabricated using CMOS-MEMS process

Sensor Review ◽

10.1108/sr-02-2016-0038 ◽

2016 ◽

Vol 36 (3) ◽

pp. 240-248 ◽

Cited By ~ 2

Author(s):

Cheng Lei ◽

Haiyang Mao ◽

Yudong Yang ◽

Wen Ou ◽

Chenyang Xue ◽

...

Keyword(s):

Design Methodology ◽

Infrared Sensor ◽

Beam Structure ◽

Ir Detectors ◽

Micro Electro Mechanical Systems ◽

Content Type ◽

High Duty Cycle ◽

Cmos Mems ◽

And Performance ◽

Mems Process

Purpose Thermopile infrared (IR) detectors are one of the most important IR devices. Considering that the surface area of conventional four-end-beam (FEB)-based thermopile devices cannot be effectively used and the performance of this type of devices is relatively low, this paper aims to present a double-end-beam (DEB)-based thermopile device with high duty cycle and performance. The paper aims to discuss these issues. Design/methodology/approach Numerical analysis was conducted to show the advantages of the DEB-based thermopile devices. Findings Structural size of the DEB-based thermopiles may be further scaled down and maintain relatively higher responsivity and detectivity when compared with the FEB-based thermopiles. The authors characterized the thermoelectric properties of the device proposed in this paper, which achieves a responsivity of 1,151.14 V/W, a detectivity of 4.15 × 108 cm Hz1/2/W and a response time of 14.46 ms sensor based on DEB structure. Orginality/value The paper proposed a micro electro mechanical systems (MEMS) thermopile infrared sensor based on double-end-beam structure.

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Novel absorber membrane and thermocouple designs for CMOS-MEMS thermoelectric infrared sensor

2017 IEEE 30th International Conference on Micro Electro Mechanical Systems (MEMS) ◽

10.1109/memsys.2017.7863638 ◽

2017 ◽

Cited By ~ 4

Author(s):

Kai-Chieh Chang ◽

Ya-Chu Lee ◽

Chih-Ming Sun ◽

Weileun Fang

Keyword(s):

Infrared Sensor ◽

Cmos Mems

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Design and Fabrication of a CMOS-MEMS Thermoelectric Infrared Microsensor

Microelectromechanical Systems ◽

10.1115/imece2005-80806 ◽

2005 ◽

Author(s):

Ke-Min Liao ◽

Da-Hong Chiou ◽

Keng-Shun Lin ◽

Rongshun Chen

Keyword(s):

Fill Factor ◽

Low Noise ◽

Sensor Response ◽

Infrared Sensor ◽

Element Analysis ◽

Broad Bandwidth ◽

Cmos Mems ◽

Transfer Behavior ◽

Noise Equivalent Temperature Difference ◽

Cmos Ic

This paper describes a thermoelectric infrared (IR) microsensor which is designed and fabricated using commercial CMOS IC processes with subsequent bulk-micromachining technology. The key feature of this sensor is that the thermocouples have been placed under the IR absorbing membrane. This infrared microsensor has the advantages of high fill factor, low noise equivalent temperature difference (NETD), and broad bandwidth. Finite element analysis has been conducted to simulate the heat transfer behavior of the device and to demonstrate the feasibility of our design. Besides, the experimental setup has been built for measuring the infrared sensor response. The results show a measured responsivity of 63 V/W and a thermal time constant of 10 ms.

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