WO2022104960A1

WO2022104960A1 - Film layer structure testing system and film layer electrical parameter testing structure

Info

Publication number: WO2022104960A1
Application number: PCT/CN2020/135858
Authority: WO
Inventors: 沈宇; 占瞻; 石正雨; 童贝
Original assignee: 瑞声声学科技(深圳)有限公司
Priority date: 2020-11-18
Filing date: 2020-12-11
Publication date: 2022-05-27
Also published as: CN112557775A; CN112557775B

Abstract

Provided is a film layer structure testing system (100), comprising a signal generation module (20), a module to be tested (10), a signal amplification module (30), and a signal processing module (40), the signal generation module (20) being used for generating a detection signal; the module to be tested (30) comprises a piezoelectric thin film (101), the module to be tested (30) is used for receiving a detection signal, the piezoelectric thin film (101) is deformed by means of the inverse piezoelectric effect and the deformation is converted into an electrical signal, then the electrical signal is used in the piezoelectric thin film (101) to generate an output electrical signal by means of the direct piezoelectric effect; the signal amplification module (30) is used for amplifying the received output electrical signal to produce an amplified electrical signal; the signal processing module (40) is used for receiving the detection signal and amplifying the electrical signal, respectively, and then performing comparison to obtain electrical parameters of the piezoelectric thin film (101). Also disclosed are two film layer electrical parameter testing structures applicable to the film layer structure testing system. In comparison with the related art, the film layer structure testing system and film layer electrical parameter testing structure are simple and easy to test.

Description

Film structure test system and film electrical parameter test structure

technical field

The invention relates to the technical field of testing, in particular to a film layer structure testing system and a film layer electrical parameter testing structure applied to piezoelectric thin films.

Background technique

Piezoelectric materials have a wide range of applications in various fields, such as piezoelectric transducers, piezoelectric sensors, piezoelectric drivers, filters, resonators, etc. With the development of semiconductor processing technology and the diversified needs of wireless terminals, MEMS piezoelectric microphones, MEMS piezoelectric speakers, SAW, and FBAR are gradually becoming commercial products. In order to meet the requirements of miniaturization, low power consumption and high performance of piezoelectric MEMS devices, the above-mentioned devices often adopt piezoelectric film layer structure (ie, piezoelectric material film), and the piezoelectric coefficient is an important indicator to measure the performance of the above-mentioned devices. . Currently, piezoelectric coefficients are generally tested using commercial equipment. Currently, piezoelectric coefficients are tested with commercial professional test equipment.

The system and structure of piezoelectric coefficient testing of related technologies generally use two methods: the first is to use the "inverse piezoelectric effect", that is, the material is deformed by the power-on signal, and then the deformation of the material is measured by optical detection equipment. Size, measure piezoelectric coefficients such as laser interferometry, laser Doppler vibrometers and piezoelectric force microscopy. The second is to use the "positive piezoelectric effect", that is, by applying a force to make a material generate an electric charge, and measuring the piezoelectric coefficient by measuring the magnitude of the electric charge.

However, the test accuracy of the related art is limited by the accuracy of the table top shape and the jig. Among them, the detection mostly uses the optical scheme to obtain the amplitude, the test system is complex and expensive, and needs to consider reflection, refraction, loss, etc. When the film structure is an ultra-fine film structure, the test spot size is limited, and the performance related to the ultra-fine film structure cannot be obtained.

Therefore, it is necessary to improve the above-mentioned system to solve the above-mentioned problems.

technical problem

The purpose of the present invention is to overcome the above technical problems, and to provide a membrane structure testing system and membrane electrical parameter testing structure with simple structure and easy testing.

technical solutions

In order to achieve the above object, the present invention provides a film structure test system, the film structure test system includes:

a signal generating module for generating a detection signal;

A module to be tested, the module to be tested includes a piezoelectric film to be tested, the module to be tested is used to receive the detection signal, and the piezoelectric film will be deformed by the inverse piezoelectric effect according to the detection signal, and converting the deformation into an electrical signal, and then generating an output electrical signal through the positive piezoelectric effect on the piezoelectric film;

a signal amplifying module, configured to receive the output electrical signal, and then amplify the received output electrical signal to generate an amplified electrical signal;

The signal processing module is used to respectively receive the detection signal and the amplified electrical signal, and then compare and process the detection signal and the amplified electrical signal to obtain electrical parameters of the piezoelectric film.

Preferably, the electrical parameters include piezoelectric coefficient, frequency response curve, quality factor and resonance frequency.

Preferably, the detection signal is a high-frequency electrical signal.

Preferably, the signal processing module is a lock-in amplifier.

Preferably, the film structure testing system is tested in a vacuum state.

The present invention also provides a film layer electrical parameter testing structure, which is applied to the film layer structure testing system according to any one of the above, wherein the piezoelectric film includes a film layer structure testing structure; the film layer electrical parameter testing structure It includes a substrate with a cavity, a piezoelectric layer, and an upper electrode and a lower electrode attached to opposite sides of the piezoelectric layer; the piezoelectric layer, the upper electrode and the lower electrode form an integrated structure, so The integrated structure is connected to the substrate through the lower electrode and suspended above the cavity; the substrate, the piezoelectric layer, the upper electrode and the lower electrode together form a resonator circuit; The upper electrode includes a first upper electrode and a second upper electrode located at opposite ends of the piezoelectric layer, the lower electrode includes a first lower electrode and a second lower electrode located at opposite ends of the piezoelectric layer, and the The first upper electrode is arranged corresponding to the first lower electrode, and the second upper electrode and the second lower electrode are arranged correspondingly; the first upper electrode is used as a signal input terminal, and the second upper electrode is used as a signal output terminal, the first lower electrode and the second lower electrode are grounded, or the first upper electrode and the second lower electrode are grounded, the first lower electrode is used as a signal input terminal, and the second lower electrode as a signal output.

Preferably, the first upper electrode includes a plurality, the first lower electrode includes a plurality; the second upper electrode includes a plurality, and the second lower electrode includes a plurality.

The present invention also provides a film layer electrical parameter testing structure, which is applied to the film layer structure testing system according to any one of the above, wherein the piezoelectric film includes a film layer structure testing structure; the film layer electrical parameter testing structure It includes a substrate with a cavity, a piezoelectric layer, and a plurality of electrode layers that are spaced on opposite sides of the piezoelectric layer. The electrode layers are three-layered and include an upper electrode layer and a middle electrode layer stacked in sequence. and the lower electrode layer, the piezoelectric layer, the upper electrode layer and the lower electrode layer form an integrated structure, one end of the integrated structure is connected to the substrate through the lower electrode layer, and the other end is suspended on the A cantilever beam is formed above the cavity; the substrate, the piezoelectric layer and the electrode layer together form a resonator circuit; the cantilever beam is a 5-layer stack structure, and the piezoelectric layer is two layers and includes a first piezoelectric layer and a second piezoelectric layer; the upper electrode layer includes a first segment upper electrode, a second segment upper electrode and a third segment upper electrode spaced apart from each other; the intermediate electrode layer includes a first segment upper electrode spaced apart from each other The middle electrode of the segment, the middle electrode of the second segment and the middle electrode of the third segment; the lower electrode layer includes the lower electrode of the first segment, the lower electrode of the second segment and the lower electrode of the third segment spaced apart from each other; the middle electrode of the first segment is a signal input terminal, the first segment upper electrode, the first segment lower electrode and the second segment middle electrode are all electrically connected to ground; the second segment upper electrode, the second segment lower electrode and The middle electrodes of the third segment are all electrically connected and in a suspended state, and the upper electrode of the third segment is electrically connected to the lower electrode of the third segment and serves as the signal output terminal.

Preferably, when the first-segment upper electrode, the first-segment middle electrode, and the first-segment lower electrode are disposed on the surfaces of opposite sides of the piezoelectric layer, the projections along the thickness direction have overlapping portions ; When the upper electrode of the second segment, the middle electrode of the second segment, and the lower electrode of the second segment are arranged on the surfaces of the opposite sides of the piezoelectric layer, the projections along the thickness direction have overlapping portions, and the When the third-segment upper electrode, the third-segment middle electrode, and the third-segment lower electrode are distributed on the surfaces of opposite sides of the piezoelectric layer, the projections along the thickness direction overlap, so that when electrical signals are applied An electric field can be generated inside the piezoelectric layer.

beneficial effect

Compared with the prior art, the film structure testing system of the present invention is provided with a signal generating module, a module to be tested, a signal amplifying module and a signal processing module. Wherein, the module to be tested is coupled through the positive piezoelectric effect and the inverse piezoelectric effect, so as to realize the generation and output of the electrical signal of the piezoelectric film, and then amplify the output electrical signal through the signal amplification module to generate the amplified electrical signal, and then use the signal amplification module to amplify the output electrical signal. The signal processing module compares the detection signal generated by the signal generating module with the amplified electrical signal to obtain electrical parameters of the piezoelectric film. The whole test system adopts electrical test, the structure of the test system is simple, and it is also easy to operate and test. The film-layer structure test structure applied to the film-layer structure test system of the present invention adopts the device of the resonator for direct electric drive and electric detection, which is convenient to operate, and can be used for the wafer-level test of the piezoelectric coefficient. The piezoelectric coefficient of the film structure; and especially in the state of device resonance, a larger output voltage can be obtained, which is conducive to signal detection and reduces power frequency interference. The film structure testing system and film electrical parameter testing The structure obtains electrical parameters with higher reliability.

Description of drawings

In order to illustrate the technical solutions in the embodiments of the present invention more clearly, the following briefly introduces the accompanying drawings used in the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, under the premise of no creative work, other drawings can also be obtained from these drawings, wherein:

Fig. 1 is the structural block diagram of the film structure test system of the present invention;

2 is a schematic structural diagram of the circuit connection relationship of the film electrical parameter testing structure of the present invention;

Fig. 3 is the relation diagram of the voltage and time of the output electric signal under the situation of different piezoelectric coefficients of piezoelectric film of the present invention;

4 is a partial three-dimensional structural schematic diagram of another film electrical parameter testing structure of the present invention;

[Correction 21.01.2021 under Rule 91]
FIG. 5 is a schematic structural diagram of the circuit connection relationship of FIG. 4 .

BEST MODE FOR CARRYING OUT THE INVENTION

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

Referring to FIG. 1 , the present invention provides a film structure testing system 100 .

The film structure testing system 100 includes a signal generation module 20 , a module to be tested 10 , a signal amplification module 30 , and a signal processing module 40 electrically connected to the signal generation module 20 and the signal amplification module 30 respectively.

The signal generating module 20 is used for generating a detection signal.

The signal generating module 20 outputs the detection signal to the module under test 10 and the signal processing module 40 respectively. Specifically, the signal generating module 20 outputs the detection signal to the signal input terminal ACINPUT of the module under test 10 and the reference input terminal REF of the signal processing module 40 respectively.

The module to be tested 10 includes the piezoelectric film 101 to be tested.

The module to be tested 10 is provided with a signal input end ACINPUT and a signal output end OUTPUT.

The signal input terminal ACINPUT is used for inputting an external detection signal.

In this embodiment, the detection signal is a high-frequency electrical signal. The high-frequency electrical signal is beneficial to deform the piezoelectric material film 1 without destroying the material.

The signal output terminal OUTPUT is used to output the electrical signal generated by the module under test 10 .

The module to be tested 10 is used for receiving the detection signal, and according to the detection signal, the piezoelectric film 101 is deformed by the inverse piezoelectric effect, and the deformation is converted into an electrical signal, and then the electrical signal is stored in the piezoelectric film 101 . The piezoelectric material film 1 generates an output electrical signal through the positive piezoelectric effect.

The inverse piezoelectric effect means that when an electric field is applied in the polarization direction of the dielectric of the piezoelectric film 101, the dielectric of the piezoelectric film 101 will produce mechanical deformation or mechanical pressure in a certain direction. When the applied electric field is removed, These deformations or stresses also disappear. The positive piezoelectric effect refers to the phenomenon of electric polarization due to deformation. When physical pressure is applied to the piezoelectric material, the electric dipole moment in the material body will be shortened due to compression. At this time, the piezoelectric material will generate an equal amount of positive and negative charges on the opposite surfaces of the material to resist this change to maintain undisturbed. This phenomenon of electric polarization through deformation is called "positive piezoelectric effect".

The signal amplifying module 30 is configured to receive the output electrical signal of the module under test 10, and then amplify the output electrical signal to generate an amplified electrical signal.

The signal amplification module 30 outputs the amplified electrical signal to the signal processing module 40 .

Specifically, the amplified electrical signal is output to the signal detection input terminal TEST of the signal processing module 40 . The output electrical signal of the signal amplification module 30 is formed by the deformation of the piezoelectric film 101 to generate charges. Wherein, the signal amplification module 30 obtains the output electrical signal of the signal output terminal OUTPUT of the module under test 10 .

The signal processing module 40 is configured to receive the detection signal and the amplified electrical signal respectively, and then compare and process the detection signal and the amplified electrical signal to obtain electrical parameters of the piezoelectric film 101 .

In this embodiment, the electrical parameters include piezoelectric coefficient d ₃₁ , frequency response curve, quality factor, and resonance frequency.

In this embodiment, the signal processing module 40 is a lock-in amplifier. The amplified electrical signal is compared with the detection signal through a lock-in amplifier, so as to couple the positive piezoelectric effect and the inverse piezoelectric effect, so that the electrical parameters of the piezoelectric film 101 are easier to obtain, especially the voltage. Electrical coefficient d ₃₁ .

In order to better realize the measurement of the piezoelectric coefficient d ₃₁ and reduce the influence of the external environment on the measurement, in this embodiment, the film structure testing system 100 is tested in a vacuum state.

(Example 1)

Referring to FIG. 2 , this embodiment is the first embodiment, and the first embodiment provides a structure 200 for testing the electrical parameters of the film layer.

The film electrical parameter testing structure 200 is applied to the film structure testing system 100 , and the piezoelectric thin film 101 includes the film electrical parameter testing structure 200 .

The film electrical parameter testing structure 200 is used to realize the coupling of the positive piezoelectric effect and the inverse piezoelectric effect; and by reasonably optimizing the electrodes, the electrical parameters of the piezoelectric film 101 can be obtained without affecting the mechanical properties.

Specifically, the film electrical parameter testing structure 200 includes a substrate 4 having a cavity 40 , a piezoelectric layer 1 , and an upper electrode 2 and a lower electrode 3 attached to opposite sides of the piezoelectric layer 1 . Wherein, the piezoelectric layer 1 is a piezoelectric thin film.

The piezoelectric layer 1 , the upper electrode 2 and the lower electrode 3 form an integrated structure, and the integrated structure is connected to the substrate 4 through the lower electrode 3 and suspended above the cavity 40 . That is, the integrated structure is located on one side of the cavity 40 along the thickness direction of the film electrical parameter testing structure 200 .

In this embodiment, the upper electrode 2 and the lower electrode 3 are respectively located at opposite ends of the long axis of the piezoelectric layer 1 .

The substrate 4, the piezoelectric layer 1, the upper electrode 2 and the lower electrode 3 together form a resonator circuit, wherein one of the upper electrode 2 or the lower electrode 3 is used as a signal input terminal, and the other is used as a signal input terminal. The upper electrode 2 or the lower electrode 3 is used as a signal output terminal.

Specifically, the upper electrode 2 includes a first upper electrode 21 and a second upper electrode 22 attached to the same side as the piezoelectric layer 1 . The first upper electrode 21 serves as the signal input end, and the The second upper electrode 22 serves as the signal output terminal.

The lower electrode 3 includes a first lower electrode 31 and a second lower electrode 32 attached to the other side of the piezoelectric layer 1 , and the first lower electrode 31 and the second lower electrode 32 are both electrically connected to ground.

In this embodiment, the piezoelectric layer 1 is rectangular. The first upper electrode 21 and the first lower electrode 31 are arranged facing each other; the second upper electrode 22 and the second lower electrode 32 are arranged facing each other; the first upper electrode 21 and the second The upper electrodes 22 are respectively disposed at opposite ends of the long axis of the piezoelectric layer 1 . This structure is conducive to the conversion of the AC signal to the positive piezoelectric effect and the inverse piezoelectric effect in the film electrical parameter testing structure 200, so that the piezoelectric coefficient d ₃₁ of the film electrical parameter testing structure 200 can be evaluated and tested. easier and more accurate.

In this embodiment, the first upper electrodes 21 include a plurality; the first lower electrodes 31 include a plurality; the first upper electrodes 21 and the first lower electrodes 31 are in one-to-one correspondence. The second upper electrode 22 includes a plurality of them. This structure makes the AC signal acting on the first upper electrode 21 and the first lower electrode 31 more evenly, so that the inverse piezoelectric effect of the piezoelectric layer 1 is easier to generate.

In this embodiment, the second lower electrodes 32 include a plurality of; the second upper electrodes 22 and the second lower electrodes 32 are in one-to-one correspondence. This structure makes it easier to obtain the output electrical signal generated by the deformation of the piezoelectric layer 1 , thereby making the evaluation and testing of the piezoelectric coefficient d ₃₁ of the piezoelectric layer 1 easier and more accurate.

Please refer to FIG. 3 . FIG. 3 is a graph showing the relationship between the voltage and time of the output electrical signal under different piezoelectric coefficients d ₃₁ of the piezoelectric layer 1 of the present invention. W1 , W2 , W3 and W4 are the voltage-time curves of the piezoelectric coefficient d ₃₁ of the piezoelectric layer 1 (ie, the piezoelectric thin film). Among them, the relationship between W1, W2, W3 and W4 is as follows: W1 is 2.0 times d ₃₁ , W2 is 1.5 times d ₃₁ , W3 is 1.0 times d ₃₁ , W4 is 0.5 times d ₃₁ , from W1, W2, From the graphs of W3 and W4, it can be concluded that the piezoelectric performance testing method and the film electrical parameter testing structure 200 of the present invention can be used for the wafer-level testing of the piezoelectric coefficient d ₃₁ . Piezoelectric coefficient d ₃₁ of the film structure _.

To sum up the above, the film layer electrical parameter testing structure 200 of the present invention adopts coupling through the positive piezoelectric effect and the inverse piezoelectric effect, so as to realize the evaluation and testing of the electrical parameters (especially the piezoelectric coefficient d ₃₁ ) of the piezoelectric layer 1 . More preferably, the film-layer electrical parameter testing structure 200 is directly electrically driven and electrically detected, which is easy to operate, and can be used for wafer-level testing with a piezoelectric coefficient d of ₃₁ , especially to obtain ultra-fine film-layer structure piezoelectricity. The coefficient d is ₃₁ ; and the whole test system adopts electrical test, the structure of the test system is simple, and it is also easy to operate and test. Especially in the state of device resonance, a larger output voltage can be obtained, which is beneficial to signal detection and _reduces power frequency interference.

(Example 2)

Please refer to FIGS. 4-5 at the same time, this embodiment is the second embodiment, and the second embodiment provides a test structure 300 for the electrical parameters of the film layer.

The film electrical parameter testing structure 300 is applied to the film structure testing system 100 , and the piezoelectric film 101 includes the film electrical parameter testing structure 300 .

The film electrical parameter testing structure 300 is used to realize the coupling of the positive piezoelectric effect and the inverse piezoelectric effect; and by reasonably optimizing the electrodes, the electrical parameters of the piezoelectric film 101 can be obtained without affecting the mechanical properties.

The difference between the film electrical parameter testing structure 300 and the film electrical parameter testing structure 200 is that the electrodes in the film electrical parameter testing structure 300 are at the same end of the piezoelectric film axis.

Specifically, the film-layer electrical parameter testing structure 300 includes a substrate 4a having a cavity 40a, a piezoelectric layer b, and a plurality of electrode layers c attached to opposite sides of the piezoelectric layer b at intervals. The electrode layer c has two layers and includes an upper electrode layer 1c, a middle electrode layer 2c and a lower electrode layer 3c.

The piezoelectric layer b, the upper electrode layer 1c and the lower electrode layer 3c form an integrated structure, one end of the integrated structure is connected to the substrate 4a through the lower electrode layer 3c, and the other end is suspended A cantilever beam is formed above the cavity 40a.

The substrate 4a, the piezoelectric layer b and the electrode layer c together form a resonator circuit, wherein one or more of the electrode layers c serve as signal input terminals, and one or more of the electrode layers c serve as a signal input terminal. A signal output terminal, wherein one or more of the electrode layers c are suspended.

In this embodiment, the cantilever beam is a 5-layer stack structure. The piezoelectric layer b has two layers and includes a first piezoelectric layer b1 and a second piezoelectric layer b2.

Specifically, the upper electrode layer 1c includes a first-segment upper electrode 1c11 , a second-segment upper electrode 1c22 and a third-segment upper electrode 1c33 that are spaced apart from each other. The intermediate electrode layer 2c includes a first-segment intermediate electrode 2c11, a second-segment intermediate electrode 2c22 and a third-segment intermediate electrode 2c33 spaced apart from each other. The lower electrode layer 3c includes a first-segment lower electrode 3c11, a second-segment lower electrode 3c22 and a third-segment lower electrode 3c33 spaced apart from each other.

Among them, the circuit connection relationship of each component is:

The first-segment middle electrode 2c11 is a signal input terminal, and the first-segment upper electrode 1c11 , the first-segment lower electrode 3c11 and the second-segment middle electrode 2c22 are all electrically connected to ground. The second-segment upper electrode 1c22, the second-segment lower electrode 3c22, and the third-segment middle electrode 2c33 are all electrically connected and in a suspended state. The third-segment upper electrode 1c33 is electrically connected to the third-segment lower electrode 3c33 and serves as the signal output terminal.

In this embodiment, the first-segment upper electrode 1c11 , the first-segment middle electrode 2c11 , and the first-segment lower electrode 3c11 are arranged along the thickness of the piezoelectric layer b on opposite sides of the piezoelectric layer b. The projections of the directions have overlapping parts. When the second-segment upper electrode 1c22, the second-segment middle electrode 2c22, and the second-segment lower electrode 3c22 are disposed on the surfaces of opposite sides of the piezoelectric layer b, the projections along the thickness direction have overlapping portions. . When the third-segment upper electrode 1c33, the third-segment middle electrode 2c33, and the third-segment lower electrode 3c33 are distributed on the surfaces of opposite sides of the piezoelectric layer b, the projections along the thickness direction have overlapping portions. , so that an electric field can be generated inside the piezoelectric layer b when an electrical signal is applied.

Through the structure and circuit connection relationship of the film electrical parameter test structure 300, the device using the multi-stage resonator is directly electrically driven and electrically detected, which is convenient to operate, and can be used for the wafer-level test of the piezoelectric coefficient d ₃₁ , especially The piezoelectric coefficient d ₃₁ of the ultra-fine film structure can be obtained. And the whole test system adopts electrical test, the structure of the test system is simple, and it is also easy to operate and test. Especially in the state of device resonance, a larger output voltage can be obtained, which is beneficial to signal detection and _reduces power frequency interference.

The above descriptions are only the embodiments of the present invention, and are not intended to limit the scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the description and drawings of the present invention, or directly or indirectly applied to other related technologies Fields are similarly included in the scope of patent protection of the present invention.

Claims

A film structure testing system, characterized in that the film structure testing system comprises:

a signal generating module for generating a detection signal;

A module to be tested, the module to be tested includes a piezoelectric film to be tested, the module to be tested is used to receive the detection signal, and the piezoelectric film will be deformed by the inverse piezoelectric effect according to the detection signal, and converting the deformation into an electrical signal, and then generating an output electrical signal through the positive piezoelectric effect on the piezoelectric film;

a signal amplifying module, configured to receive the output electrical signal, and then amplify the received output electrical signal to generate an amplified electrical signal;

The signal processing module is used to respectively receive the detection signal and the amplified electrical signal, and then compare and process the detection signal and the amplified electrical signal to obtain electrical parameters of the piezoelectric film.
The film structure testing system according to claim 1, wherein the electrical parameters include piezoelectric coefficient, frequency response curve, quality factor and resonance frequency.
The film structure testing system according to claim 1, wherein the detection signal is a high-frequency electrical signal.
The film structure testing system according to claim 1, wherein the signal processing module is a lock-in amplifier.
The film structure testing system according to claim 1, wherein the film structure testing system is tested in a vacuum state.
A film electrical parameter test structure, characterized in that, it is applied to the film structure test system according to any one of claims 1-5, and the piezoelectric thin film includes a film structure test structure; the film The layer electrical parameter testing structure includes a substrate with a cavity, a piezoelectric layer, and upper and lower electrodes attached to opposite sides of the piezoelectric layer; the piezoelectric layer, the upper electrode and the lower electrode An integrated structure is formed, and the integrated structure is connected with the substrate through the lower electrode and suspended above the cavity; the substrate, the piezoelectric layer, the upper electrode and the lower electrode are common A resonator circuit is formed; the upper electrode includes a first upper electrode and a second upper electrode at opposite ends of the piezoelectric layer, and the lower electrode includes a first lower electrode and a second upper electrode at opposite ends of the piezoelectric layer a lower electrode, the first upper electrode is arranged corresponding to the first lower electrode, and the second upper electrode and the second lower electrode are arranged correspondingly; the first upper electrode is used as a signal input terminal, the second upper electrode is The upper electrode is used as a signal output terminal, the first lower electrode and the second lower electrode are grounded, or the first upper electrode and the second lower electrode are grounded, and the first lower electrode is used as a signal input terminal, so the The second lower electrode is used as a signal output terminal.
The film electrical parameter testing structure according to claim 6, wherein the first upper electrode comprises a plurality of the first lower electrodes; the second upper electrode comprises a plurality of the The second lower electrode includes a plurality of them.
A film electrical parameter test structure, characterized in that, it is applied to the film structure test system according to any one of claims 1-5, and the piezoelectric thin film includes a film structure test structure; the film The layered electrical parameter testing structure includes a substrate with a cavity, a piezoelectric layer, and a plurality of electrode layers attached to opposite sides of the piezoelectric layer at intervals. The electrode layers are three layers and include upper electrodes stacked in sequence. layer, middle electrode layer and lower electrode layer, the piezoelectric layer, the upper electrode layer and the lower electrode layer form an integrated structure, one end of the integrated structure is connected to the substrate through the lower electrode layer, The other end is suspended above the cavity to form a cantilever beam; the substrate, the piezoelectric layer and the electrode layer together form a resonator circuit; the cantilever beam is a 5-layer stack structure, and the piezoelectric layer It is two layers and includes a first piezoelectric layer and a second piezoelectric layer; the upper electrode layer includes a first segment upper electrode, a second segment upper electrode and a third segment upper electrode spaced apart from each other; the middle electrode layer includes a first-segment middle electrode, a second-segment middle electrode, and a third-segment middle electrode that are spaced apart from each other; the lower electrode layer includes a first-segment lower electrode, a second-segment lower electrode, and a third-segment lower electrode that are spaced apart from each other; the The first-segment middle electrode is a signal input end, and the first-segment upper electrode, the first-segment lower electrode, and the second-segment middle electrode are all electrically connected to ground; the second-segment upper electrode, the first The second-segment lower electrode and the third-segment middle electrode are both electrically connected and in a suspended state, and the third-segment upper electrode is electrically connected to the third-segment lower electrode and serves as the signal output end.
The film electrical parameter testing structure according to claim 8, wherein the first segment upper electrode, the first segment middle electrode, and the first segment lower electrode are disposed on the piezoelectric layer. When the surfaces of the opposite sides are projected along the thickness direction, there are overlapping parts; the second upper electrode, the second middle electrode, and the second lower electrode are arranged on the opposite sides of the piezoelectric layer When the surface of the piezoelectric layer is projected along the thickness direction, there are overlapping parts, and the third segment upper electrode, the third segment middle electrode, and the third segment lower electrode are distributed on the surfaces of the opposite sides of the piezoelectric layer. The projections in the thickness direction have overlapping portions so that an electric field can be generated inside the piezoelectric layer when an electrical signal is applied.