TWI232291B - Resonance sensor and fabrication method thereof - Google Patents

Abstract

A resonance sensor and fabrication method thereof. The resonance sensor comprises a resonator and a sensing layer of a plurality of nanowires coupled thereto, whereby an analyte is sensed via absorption or reaction mechanisms on the nanowires. The fabrication method of the resonance sensor comprises providing a resonator with a substrate, forming a layer of nanowires on the substrate, and defining a predetermined area of the layer by lithography to form a sensing layer.

Description

1232291

In the technical field to which the invention belongs, ancient technology relates to a resonance sensor and a manufacturing method thereof, and in particular-a resonance sensor using nanowires as a sensing layer and its previous technology can be divided into many types, such as pressure The resistance method has the advantages of high-sensitivity physical sensor based on sensing principle type, capacitive type, piezoelectric type, resonance type and other high sensitivity.

In terms of gas sensing technology, traditional methods such as R or spectrometry, mass spectrometer, electrochemistry, and catalyst have been used. However, they all have problems such as time consuming, large volume, interactive sensitivity and selectivity. In recent years, the resonance method has gradually replaced the traditional gas sensing method, and has become the mainstream of gas sensing technology, which can achieve the goals of low cost, accurate detection, and fast. There are various implementations of resonance sensing, but the most commonly used method is acoustic resonance. The sensing layer is coated on the piezoelectric substrate. When gas molecules are adsorbed on the surface of the sensing layer, the relative mass is increased, resulting in a change in the frequency of the acoustic wave. Based on the principle that the amount of change in acoustic frequency is proportional to the mass absorbed by the sensing layer, gas composition and composition can be sensed.

The sensing elements that use acoustic resonance as the sensing principle usually use piezoelectric acoustic wave elements, which are mainly divided into two categories: quartz crystal microbalance (Quartz

Crystal Microbalance (QCM) and Surface Acoustic Wave (Surface

Acoustic Wave (SAW) element. QCM has been widely used, its advantages are good linearity and less temperature sensitivity, but its biggest disadvantage is that the operating frequency is too high.

0178-A20201TWF (N1); P05920070TW; renee.p t d 1232291 V. Description of the invention (3) The delay line method is adopted. When the wave is transmitted, the surface acoustic wave reacts with the sensing layer to disturb the wave transmission characteristics and cause changes such as wave speed and attenuation. Because when the surface acoustic wave propagates in the piezoelectric material, mechanical deformation and potential energy change occur at the same time and they face each other. Therefore, when the surface wave reacts with the sensing layer, the wave velocity and attenuation will change. The acoustic wave and the sensing layer will produce a mechanical surface. For example, mass-loading is the change in surface wave displacement caused by the change in surface quality. If the deformation of the surface sensing layer is caused by a surface wave, it is an elastic or viscoelastic (ViSCOelastic) effect. The effect of ^ includes the acousto-optic characteristics of the surface wave electric field and the charge source in the conductive film. Theoretically, a surface acoustic wave element can detect any gas through the selection of a sensing layer. However, in fact, the limit values of the detectable concentration and boundary sensitivity have a considerable relationship with the sensing layer used. This feeling; the use of high molecular weight, its low cost, simple production is its advantages, as the environmental impact of deterioration and deterioration caused by the characteristics are not easy to grasp and reliability. This makes the control circuit difficult to match, making the overall production cost Ultra-high surface efficient catalysts and various gas detection devices such as zinc oxide nanowires can be more energy efficient than traditional ones, but the detection method must be adopted and expensive. The volume / volume ratio characteristic, therefore, has considerable potential in. At present, the use of non-directional molecular materials has better infrared detection equipment, and it is not easy to synthesize the above. How to propose a novel sensing layer for the resonance sensing element to change the emerging mainstream of detection technology, local molecular sensing layer Easy to change

1232291

And the disadvantage of poor selectivity, black accounted for 0, is the re-invention of the current development of resonance sensing technology. In view of this, the purpose of the present invention is to solve the problem that the conventional resonance sensing element and the sub-sensing layer are easily deteriorated. Provide a high-surface, south-sensitivity sensing layer to enhance the sensing performance of the resonance sensing element. In order to achieve the above purpose, the present invention proposes a method for applying nanowires to resonance sensing parts. On the one hand, nanowires are used to replace polymer materials, in addition to avoiding deterioration and degradation, and at the same time, the high depth of the nanostructure The aspect ratio greatly enhances the adsorption and desorption capabilities to increase the sensing sensitivity and selectivity of the resonance sensing element. On the other hand, the development of the application of nano-wires on resonance sensing elements has the advantages of low production cost, high sensitivity, and simple detection method compared with the use of infrared detection. The present invention proposes a resonance sensor, which includes a resonator and a sensing layer coupled to the resonator. The sensing layer is composed of a plurality of nanowires. The functions of adsorption and reaction to a test object enable the resonance sensor to detect the test object. According to the resonance sensor of the present invention, the resonator may be an acoustic wave resonance element ', such as a surface acoustic wave resonance element. The resonance sensor of the present invention, if it is a surface acoustic wave resonance element, further includes a piezoelectric substrate, and an interdigital transducer (IDT) is formed on the piezoelectric substrate. &

Brief description of the drawings Figure 1 is a schematic diagram of a conventional surface acoustic wave sensor. Figures 2A and 2B show the results of measuring the adsorption and desorption properties of zinc oxide nanowires using the infrared light fading total reflection technique, respectively. Fig. 3 is a perspective view of a resonance sensor using a surface acoustic wave element as a resonator according to the present invention. Figure 4 shows the special shape and positioning of nanowires according to the present invention. Figure 5 shows the manufacturing process of the embodiment of the present invention. FIG. 6 shows the surface acoustic wave common sensor symbol description of the embodiment. Conventional technique 1 ~ conventional surface acoustic wave sensor; 2 ~ piezoelectric substrate, 31, 32 ~ parent interdigital electrode converter; 4 ~ Sensing layer. In the present invention, 2 to piezoelectric substrates, 3 1, 3 2 to interdigital electrode converters, 5 to nanometer wires, and 10 to resonance sensors.

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Claims (1)

1232291 VI. Scope of patent application1. A resonance sensor comprising: a resonator; and a sensing layer coupled to the resonator, wherein the sensing layer is composed of a plurality of nanowires, and The adsorption or reaction of the nanowire to a test object makes the resonance sensor change to detect the test object. 2. The resonance sensor according to item 1 of the scope of patent application, wherein the resonator is an acoustic wave resonance element. 3. The resonance sensor according to item 2 of the scope of patent application, wherein the resonator is a surface acoustic wave resonance element. 4. The resonance sensor according to item 2 of the scope of the patent application, wherein the resonator further comprises a piezoelectric substrate, and an interdigital transducer is formed on the piezoelectric substrate. 5. The resonance sensor according to item 4 of the patent application, wherein the piezoelectric substrate is quartz, lithium niobate, or lithium tantalate. 6. The resonance sensor according to item 2 of the scope of patent application, wherein the resonator includes a piezoelectric thin film fabricated on a semiconductor substrate, and an interdigitated electrode transducer is formed on the piezoelectric thin film. 7. The resonance sensor according to item 6 of the patent application, wherein the semiconductor substrate is silicon or gallium arsenide. 8. The resonance sensor according to item 2 of the scope of patent application, wherein the resonator is a quartz resonator element. 9. The resonance sensor according to item 2 of the scope of patent application, wherein the resonator is a body wave resonance element. 0178-A20201TWF (Nl); P05920070TW; renee.ptd Page 14 1232291 ^ ---- 6. Scope of patent application 1 0 · As for item 1 of the scope of patent application. Special nanowires are formed from oxides. The "1". Resonant nanowires as described in the scope of the patent application β are made of zinc oxide. Among which 12. As the scope of patent application! The resonance sensor described in the item = includes a wireless receiving and / or wireless transmitting device, which makes it a step detector. F two-pronged sensing includes a 3 ·· method for manufacturing a resonance sensor, which provides a resonator having a substrate, which is composed of a plurality of nanowires forming a nanowire layer on the above substrate, and, The lithographic method is used to define the nanowire layer into a predetermined area for use as a sensing layer. The adsorption of the sensing layer on a test object enables the resonance sensor to detect the test object. . 14. The manufacturing method of the resonance sensor according to item 13 of the scope of patent application, wherein the resonator is an acoustic wave resonance element. 1 5 · The manufacturing method of the resonance sensor according to item 4 of the patent application scope, wherein the resonator is a surface acoustic wave resonance element. [16] The method for manufacturing a resonance sensor according to item 15 of the scope of patent application, wherein the resonator further includes a piezoelectric substrate, and an interdigital electrode converter is formed on the piezoelectric substrate. 17 · The manufacturing method of the resonance sensor according to item 16 of the scope of patent application, wherein the piezoelectric substrate is quartz, lithium niobate or lithium tantalate. 1 8 · Manufacture of resonance sensor as described in item 14 of the scope of patent application 0178-A20201TWF (Nl); P05920070TW; renee.ptd Page 15 1232291 Sixth, the scope of patent application _ Fang Qu, where the resonator package is on top, and-cross-finger electrode conversion = film made on a semiconductor substrate method, stand The manufacturing of the resonance sensor described in the semiconductor 8 f /, the base of the yak conductor is silicon or arsenide 2 0. If the scope of the patent application is Chu 14, the method is described in Qiu Zhen + A + The production of the resonance sensor is Hagaraki, and the iron is a quartz resonator element. The method of manufacturing the resonance sensor according to item 14 of Fang Feng 2 ’, wherein the resonator is a body wave resonance element. Operation 22. The resonance sensor described in item 13 of the patent scope, wherein the nanowire is formed of an oxide. 23. The manufacturing method of the resonance sensor according to item 13 of the scope of the patent application, wherein the nanowire is formed of zinc oxide. 24. The manufacturing method of the resonance sensor as described in item 3 of the patent application scope, further comprising a wireless receiving and / or wireless transmitting device, which can be used as a remote sensing sensor. One