Piezoelectric film resonance sensor with semi-oval micro flow channel

Abstract

The invention discloses a piezoelectric film resonance sensor with a semi-oval micro flow channel. The sensor comprises a substrate, a sound reflection layer, a piezoelectric stack and a micro flow channel which is arranged above the piezoelectric stack. The micro flow channel is made from a thermoplastic high polymer material, the cross section of the micro flow channel is of a semi-oval shape, the center of a horizontal shaft of the micro flow channel is the central point of the piezoelectric stack, and the length of the horizontal shaft is 3-5 times that of the piezoelectric stack. The distance from the highest point inside the micro flow channel to the piezoelectric stack is integer multiple of a half of the stationary wave resonance wave length in the piezoelectric stack, the multiple is in a range of 40-100, and the height of a side wall of the micro flow channel is 5-10 times the distance from the highest point inside the micro flow channel to the piezoelectric stack. Sound wave can be reflected towards the center of the piezoelectric stack by the micro flow channel and the oval interface of a liquid sample in the micro flow channel, thus the loss of sound wave energy is reduced to a certain extent, and the resonance performance and the sensing performance of the sensor are improved.

Description

Technical field

[0001] The invention relates to the technical field of biochemical sensors, in particular, to a piezoelectric thin-film resonant sensor with semi-elliptical micro-channels. Background technique

[0002] Biochemical sensors are a very important type of sensor, which are widely used in industrial control, environmental monitoring, chemical substance analysis, biological gene detection, protein analysis, etc. The existing biochemical sensors mainly include electrochemical sensors, optical fiber sensors, surface plasmon resonance sensors, semiconductor sensors, and quartz microbalance sensors. These sensors themselves or their signal analysis devices are large in size and difficult to be integrated and arrayed on a large scale, and the detection time is long and the cost is high.

[0003] Piezoelectric film resonance sensor is a sensor based on the principle of adsorption quality sensitivity. The sensor uses piezoelectric film to generate high-frequency electroacoustic...

Examples

Embodiment 1

[0031] This embodiment is a piezoelectric thin-film resonant sensor with semi-elliptical micro-channels operating in longitudinal wave mode.

[0032] The device is fabricated on a silicon substrate 101, and an air gap with a thickness of 1 μm is set as the acoustic reflection layer 102 under the piezoelectric stack 103.

[0033] The length 106 of the piezoelectric stack 103 is 300 microns, and the structure of the piezoelectric stack 103 is as figure 2 Shown. The piezoelectric film 201 is a 2 μm thick aluminum nitride film, and the electrode 202 has a square sandwich structure, clamped on the upper and lower sides of the piezoelectric film 201. The size of the upper electrode 203 is 100 μm×100 μm, and the size of the bottom electrode 204 is 200 μm×200 μm. In the piezoelectric film 201, a longitudinal wave mode acoustic wave resonance of about 2.6 GHz is excited. The construction material of the micro flow channel 104 is polydimethylsiloxane.

[0034] According to the numerical sim...

Embodiment 2

[0037] This embodiment is a piezoelectric thin-film resonant sensor with semi-elliptical micro-channels operating in shear wave mode.

[0038] The device is fabricated on a silicon substrate 101, and an air gap with a thickness of 1 μm is set as the acoustic reflection layer 102 under the piezoelectric stack 103.

[0039] The length 106 of the piezoelectric stack 103 is 300 microns, and the structure of the piezoelectric stack 103 is as Figure 4 Shown. The piezoelectric film 201 is a 1 micron thick aluminum nitride film, the electrode 202 has a long parallel structure, and the first electrode 301 and the second electrode 302 are both arranged on the upper surface side of the piezoelectric film 201. The size of the first electrode 301 is 150 μm×300 μm, the size of the second electrode 302 is 100 μm×300 μm, and the distance between the two electrodes is 10 μm. In the piezoelectric film 201, a shear wave acoustic resonance of about 3.0 gigahertz is excited. The construction materia...

Technical field

[0001] The invention relates to the technical field of biochemical sensors, in particular, to a piezoelectric thin-film resonant sensor with semi-elliptical micro-channels. Background technique

[0002] Biochemical sensors are a very important type of sensor, which are widely used in industrial control, environmental monitoring, chemical substance analysis, biological gene detection, protein analysis, etc. The existing biochemical sensors mainly include electrochemical sensors, optical fiber sensors, surface plasmon resonance sensors, semiconductor sensors, and quartz microbalance sensors. These sensors themselves or their signal analysis devices are large in size and difficult to be integrated and arrayed on a large scale, and the detection time is long and the cost is high.

[0003] Piezoelectric film resonance sensor is a sensor based on the principle of adsorption quality sensitivity. The sensor uses piezoelectric film to generate high-frequency electroacoustic...

Examples

Embodiment 1

[0031] This embodiment is a piezoelectric thin-film resonant sensor with semi-elliptical micro-channels operating in longitudinal wave mode.

[0032] The device is fabricated on a silicon substrate 101, and an air gap with a thickness of 1 μm is set as the acoustic reflection layer 102 under the piezoelectric stack 103.

[0033] The length 106 of the piezoelectric stack 103 is 300 microns, and the structure of the piezoelectric stack 103 is as figure 2 Shown. The piezoelectric film 201 is a 2 μm thick aluminum nitride film, and the electrode 202 has a square sandwich structure, clamped on the upper and lower sides of the piezoelectric film 201. The size of the upper electrode 203 is 100 μm×100 μm, and the size of the bottom electrode 204 is 200 μm×200 μm. In the piezoelectric film 201, a longitudinal wave mode acoustic wave resonance of about 2.6 GHz is excited. The construction material of the micro flow channel 104 is polydimethylsiloxane.

[0034] According to the numerical sim...

Embodiment 2

[0037] This embodiment is a piezoelectric thin-film resonant sensor with semi-elliptical micro-channels operating in shear wave mode.

[0038] The device is fabricated on a silicon substrate 101, and an air gap with a thickness of 1 μm is set as the acoustic reflection layer 102 under the piezoelectric stack 103.

[0039] The length 106 of the piezoelectric stack 103 is 300 microns, and the structure of the piezoelectric stack 103 is as Figure 4 Shown. The piezoelectric film 201 is a 1 micron thick aluminum nitride film, the electrode 202 has a long parallel structure, and the first electrode 301 and the second electrode 302 are both arranged on the upper surface side of the piezoelectric film 201. The size of the first electrode 301 is 150 μm×300 μm, the size of the second electrode 302 is 100 μm×300 μm, and the distance between the two electrodes is 10 μm. In the piezoelectric film 201, a shear wave acoustic resonance of about 3.0 gigahertz is excited. The construction materia...

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