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A Meliorated Multi-Frequency Band Pyroelectric Sensor.

Hsiao CC, Liu SY, Siao AS - Sensors (Basel) (2015)

Bottom Line: The proposed sensor is built on a silicon substrate with a thermal isolation layer of a silicon nitride film, consisting of four pyroelectric layers with various thicknesses deposited by a sputtering or aerosol deposition (AD) method and top and bottom electrodes.The fabricated device is effective in the range of 1 KHz~10 KHz with a rapid response and high voltage responsivity, while the ZnO layers with thicknesses of about 0.8 μm, 6 μm, 10 μm and 16 μm are used for fabricating the meliorated multi-frequency band pyroelectric sensor.The proposed sensor is successfully designed, analyzed, and fabricated in the present study, and can indeed extend the sensing range of the multi-frequency band.

View Article: PubMed Central - PubMed

Affiliation: Department of Mechanical Design Engineering, National Formosa University, No. 64, Wunhua Rd., Huwei Township, Yunlin County 632, Taiwan. cchsiao@nfu.edu.tw.

ABSTRACT
This article proposes a meliorated multi-frequency band pyroelectric sensor for detecting subjects with various velocities, namely extending the sensing frequency under good performance from electrical signals. A tactic, gradually increasing thickness of the ZnO layers, is used for redeeming drawbacks of a thicker pyroelectric layer with a tardy response at a high-frequency band and a thinner pyroelectric layer with low voltage responsivity at a low-frequency band. The proposed sensor is built on a silicon substrate with a thermal isolation layer of a silicon nitride film, consisting of four pyroelectric layers with various thicknesses deposited by a sputtering or aerosol deposition (AD) method and top and bottom electrodes. The thinnest ZnO layer is deposited by sputtering, with a low thermal capacity and a rapid response shoulders a high-frequency sensing task, while the thicker ZnO layers are deposited by AD with a large thermal capacity and a tardy response shoulders a low-frequency sensing task. The fabricated device is effective in the range of 1 KHz~10 KHz with a rapid response and high voltage responsivity, while the ZnO layers with thicknesses of about 0.8 μm, 6 μm, 10 μm and 16 μm are used for fabricating the meliorated multi-frequency band pyroelectric sensor. The proposed sensor is successfully designed, analyzed, and fabricated in the present study, and can indeed extend the sensing range of the multi-frequency band.

No MeSH data available.


Calculated Voltage responsivities of a meliorated multi-frequency band pyroelectric sensor with TPZ = 0.3 μm, TAZ1 = 3 μm, TAZ2 = 1 μm and TAZ3 = 0.6 μm under incident irradiation power modulated by various chopping frequencies of about (a) 14 KHz, (b) 33 KHz and (c) 100 KHz.
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sensors-15-16248-f010: Calculated Voltage responsivities of a meliorated multi-frequency band pyroelectric sensor with TPZ = 0.3 μm, TAZ1 = 3 μm, TAZ2 = 1 μm and TAZ3 = 0.6 μm under incident irradiation power modulated by various chopping frequencies of about (a) 14 KHz, (b) 33 KHz and (c) 100 KHz.

Mentions: Transient temperature fields with various chopping frequencies were simulated for further calculation of voltage responsivities when the meliorated multi-frequency band pyroelectric sensors were exposed to irradiation power with various chopping periods. A square waveform was produced using a programmable function generator to modulate the irradiation power with chopping frequencies of about 14 KHz, 33 KHz and 100 KHz. Figure 10 shows the voltage responsivities of a meliorated multi-frequency band pyroelectric sensor with TPZ = 0.3 μm, TAZ1 = 3 μm, TAZ2 = 1 μm and TAZ3 = 0.6 μm when the incident irradiation power was modulated with various chopping frequencies of about 14 KHz, 33 KHz and 100 KHz. The shape of the integrated voltage responsivity of VT at three chopping frequencies almost approached a square wave. Furthermore, the amplitude of the integrated voltage responsivity of VT increased when chopping frequencies decreased. This trend conformed to Equation (3). Moreover, the heat absorption of pyroelectric elements decreased for further transforming into electrical energy while the chopping frequency increased. Therefore, VT generated by gradually increasing the thicknesses of the ZnO layers had a compensatory effect among the ZnO layers with various thicknesses. It was obvious that VT generated by several ZnO layers with various thicknesses would be advantageous in expanding the sensing frequency band with a rapid response. The wave form of VT approached a square shape, which presented that VT possessed identical voltage responsivity to the rapid response. This implied that the integrated voltage responsivity of VT generated by meliorated multi-frequency band pyroelectric sensors could present performances of various pyroelectric devices at various sensing frequency bands.


A Meliorated Multi-Frequency Band Pyroelectric Sensor.

Hsiao CC, Liu SY, Siao AS - Sensors (Basel) (2015)

Calculated Voltage responsivities of a meliorated multi-frequency band pyroelectric sensor with TPZ = 0.3 μm, TAZ1 = 3 μm, TAZ2 = 1 μm and TAZ3 = 0.6 μm under incident irradiation power modulated by various chopping frequencies of about (a) 14 KHz, (b) 33 KHz and (c) 100 KHz.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4541877&req=5

sensors-15-16248-f010: Calculated Voltage responsivities of a meliorated multi-frequency band pyroelectric sensor with TPZ = 0.3 μm, TAZ1 = 3 μm, TAZ2 = 1 μm and TAZ3 = 0.6 μm under incident irradiation power modulated by various chopping frequencies of about (a) 14 KHz, (b) 33 KHz and (c) 100 KHz.
Mentions: Transient temperature fields with various chopping frequencies were simulated for further calculation of voltage responsivities when the meliorated multi-frequency band pyroelectric sensors were exposed to irradiation power with various chopping periods. A square waveform was produced using a programmable function generator to modulate the irradiation power with chopping frequencies of about 14 KHz, 33 KHz and 100 KHz. Figure 10 shows the voltage responsivities of a meliorated multi-frequency band pyroelectric sensor with TPZ = 0.3 μm, TAZ1 = 3 μm, TAZ2 = 1 μm and TAZ3 = 0.6 μm when the incident irradiation power was modulated with various chopping frequencies of about 14 KHz, 33 KHz and 100 KHz. The shape of the integrated voltage responsivity of VT at three chopping frequencies almost approached a square wave. Furthermore, the amplitude of the integrated voltage responsivity of VT increased when chopping frequencies decreased. This trend conformed to Equation (3). Moreover, the heat absorption of pyroelectric elements decreased for further transforming into electrical energy while the chopping frequency increased. Therefore, VT generated by gradually increasing the thicknesses of the ZnO layers had a compensatory effect among the ZnO layers with various thicknesses. It was obvious that VT generated by several ZnO layers with various thicknesses would be advantageous in expanding the sensing frequency band with a rapid response. The wave form of VT approached a square shape, which presented that VT possessed identical voltage responsivity to the rapid response. This implied that the integrated voltage responsivity of VT generated by meliorated multi-frequency band pyroelectric sensors could present performances of various pyroelectric devices at various sensing frequency bands.

Bottom Line: The proposed sensor is built on a silicon substrate with a thermal isolation layer of a silicon nitride film, consisting of four pyroelectric layers with various thicknesses deposited by a sputtering or aerosol deposition (AD) method and top and bottom electrodes.The fabricated device is effective in the range of 1 KHz~10 KHz with a rapid response and high voltage responsivity, while the ZnO layers with thicknesses of about 0.8 μm, 6 μm, 10 μm and 16 μm are used for fabricating the meliorated multi-frequency band pyroelectric sensor.The proposed sensor is successfully designed, analyzed, and fabricated in the present study, and can indeed extend the sensing range of the multi-frequency band.

View Article: PubMed Central - PubMed

Affiliation: Department of Mechanical Design Engineering, National Formosa University, No. 64, Wunhua Rd., Huwei Township, Yunlin County 632, Taiwan. cchsiao@nfu.edu.tw.

ABSTRACT
This article proposes a meliorated multi-frequency band pyroelectric sensor for detecting subjects with various velocities, namely extending the sensing frequency under good performance from electrical signals. A tactic, gradually increasing thickness of the ZnO layers, is used for redeeming drawbacks of a thicker pyroelectric layer with a tardy response at a high-frequency band and a thinner pyroelectric layer with low voltage responsivity at a low-frequency band. The proposed sensor is built on a silicon substrate with a thermal isolation layer of a silicon nitride film, consisting of four pyroelectric layers with various thicknesses deposited by a sputtering or aerosol deposition (AD) method and top and bottom electrodes. The thinnest ZnO layer is deposited by sputtering, with a low thermal capacity and a rapid response shoulders a high-frequency sensing task, while the thicker ZnO layers are deposited by AD with a large thermal capacity and a tardy response shoulders a low-frequency sensing task. The fabricated device is effective in the range of 1 KHz~10 KHz with a rapid response and high voltage responsivity, while the ZnO layers with thicknesses of about 0.8 μm, 6 μm, 10 μm and 16 μm are used for fabricating the meliorated multi-frequency band pyroelectric sensor. The proposed sensor is successfully designed, analyzed, and fabricated in the present study, and can indeed extend the sensing range of the multi-frequency band.

No MeSH data available.