阅读说明：本技术 氧化镓在压电材料上的应用及压电薄膜、压电器件 (Application of gallium oxide in piezoelectric material, piezoelectric film and piezoelectric device ) 是由 陈梓敏 卢星 王钢 于 2020-07-20 设计创作，主要内容包括：本发明公开了氧化镓在压电材料上的应用及压电薄膜、压电器件,涉及压电材料技术。针对现有技术在压电材料选择中对压电系数的技术偏见提出本方案,ε相氧化镓在压电材料上的应用。压电薄膜由ε相氧化镓制成。应用ε相氧化镓的压电器件。优点在于,相对介电常数仅有ε<Sub>r</Sub>＝3.6,可以保证外部输入的交流电信号高效的转化为机械振动能,这就弥补了ε相氧化镓在压电系数方面的不足。而且由于ε相氧化镓具有超宽禁带,绝缘性好,可以避免了压电器件工作过程中由于漏电流导致的热损耗,提升压电器件的能量转换效率。ε相氧化镓是一种适用于制备高性能压电器件的新型半导体材料。(The invention discloses application of gallium oxide on a piezoelectric material, a piezoelectric film and a piezoelectric device, and relates to the piezoelectric material technology. The scheme is provided aiming at the technical prejudice of the prior art on the piezoelectric coefficient in the selection of the piezoelectric material, and the phase gallium oxide is applied to the piezoelectric material. The piezoelectric film is made of phase gallium oxide. Piezoelectric devices employing phase gallium oxide. Has the advantage that the relative dielectric constant is only r 3.6, the high-efficiency conversion of the externally input alternating current signal into mechanical vibration energy can be ensured, and the defect of the phase gallium oxide in the aspect of piezoelectric coefficient is overcome. And because the phase gallium oxide has an ultra-wide forbidden band, the insulation property is good, the heat loss caused by leakage current in the working process of the piezoelectric device can be avoided, and the energy conversion efficiency of the piezoelectric device is improved. The phase gallium oxide is a novel semiconductor material suitable for preparing a high-performance piezoelectric device.)

1. Use of gallium oxide in a piezoelectric material, wherein the gallium oxide is phase gallium oxide.

2. A piezoelectric film characterized by being made of phase gallium oxide.

3. The piezoelectric film according to claim 2, wherein the phase gallium oxide is prepared at a temperature of not higher than 850 ℃.

4. The piezoelectric thin film according to claim 2, wherein the thickness is 0.1 to 100 μm.

5. The piezoelectric film according to claim 2, wherein a crystal plane of the surface is oriented in a (001) orientation.

6. The piezoelectric thin film according to claim 2, wherein the phase gallium oxide is crystallized on a foreign substrate, and an actual crystal orientation of the substrate surface has an inclination angle of 0 to 6 ° with respect to a crystal orientation of the substrate.

7. The piezoelectric thin film according to claim 6, wherein the foreign substrate is sapphire, 4H-SiC, 6H-SiC, GaAs, InP, Si, SiO₂One of the components,/Si.

8. The piezoelectric thin film according to claim 6, wherein the foreign substrate crystal orientation is sapphire (001), 4H-SiC (001), 6H-SiC (001), GaAs (111), InP (111), Si (111), SiO₂One of the compounds,/Si (111).

9. A piezoelectric device using the piezoelectric thin film according to any one of claims 2 to 8.

10. A piezoelectric device according to claim 10, in particular a piezoelectric resonator, a temperature sensor, a chemical sensor.

Technical Field

The present invention relates to a gallium oxide-based piezoelectric material, a piezoelectric thin film, and a piezoelectric device.

Background

The piezoelectric material is widely applied to the construction of radio frequency filters and oscillators and is one of important devices in the field of radio frequency communication; furthermore, piezoelectric resonators based on piezoelectric materials can also be used to implement temperature, chemical sensors. With the development of piezoelectric material technology, the development trend of piezoelectric devices is high frequency, low power consumption, miniaturization, integration, low cost and the like; the piezoelectric device based on the piezoelectric thin film material has the advantages of frequency, power capacity, volume and cost which are incomparable with the piezoelectric device made of the traditional ceramic body material. The working principle of the piezoelectric device is that a radio frequency electric signal excites acoustic wave oscillation in a piezoelectric film through an electrode so as to realize resonance of specific frequency. Therefore, the electromechanical coupling coefficient of the thin film is critical to determine the performance of the resonator.

In order to raise the electromechanical coupling coefficient of the resonator, the material generally used needs to have a strong piezoelectric coefficient, such as the piezoelectric coefficient e of AlN material₃₃＝1.55C/m². The research and development of the existing piezoelectric materials are developing towards the search of materials with higher piezoelectric coefficients.

Disclosure of Invention

The invention aims to realize the application of gallium oxide on piezoelectric materials, a piezoelectric film and a piezoelectric device so as to provide more selectivity for the piezoelectric materials.

Use of gallium oxide as a phase gallium oxide in a piezoelectric material.

The piezoelectric film is made of phase gallium oxide.

The preparation temperature of the phase gallium oxide of the piezoelectric film is not higher than 850 ℃.

The thickness of the piezoelectric film is 0.1-100 microns.

The crystal plane orientation of the surface of the piezoelectric film is (001) orientation.

The phase gallium oxide of the piezoelectric film is crystallized on the foreign substrate, and the actual crystal orientation of the surface of the substrate has an inclination angle of 0-6 degrees relative to the crystal orientation of the substrate.

The heterogeneous substrate is sapphire, 4H-SiC, 6H-SiC, GaAs, InP, Si, SiO₂One of the components,/Si. The crystal orientation is preferably sapphire (001), 4H-SiC (001), 6H-SiC (001), GaAs (111), InP (111), Si (111), SiO₂One of the compounds,/Si (111).

A piezoelectric device using the piezoelectric thin film. In particular piezoelectric resonators, temperature sensors, chemical sensors.

The application of the gallium oxide on the piezoelectric material, the piezoelectric film and the piezoelectric device have the advantages that the phase gallium oxide piezoelectric coefficient is only e₃₃＝0.94C/m²On the other hand, however, the relative dielectric constant is only_r3.6, which is significantly lower than the relative dielectric constant of conventional piezoelectric materials. The high-efficiency conversion of the externally input alternating current signal into mechanical vibration energy can be ensured, and the defect of phase gallium oxide in the aspect of piezoelectric coefficient is overcome. And because the phase gallium oxide has an ultra-wide forbidden band of 5eV, the phase gallium oxide has good insulativity, can avoid heat loss caused by leakage current in the working process of the piezoelectric device, and improves the energy conversion efficiency of the piezoelectric device. Therefore, considering the comprehensive properties of the materials in three aspects of piezoelectric coefficient, dielectric constant and forbidden band width, the phase gallium oxide can be considered as a novel semiconductor material suitable for preparing high-performance piezoelectric devices.

Drawings

FIG. 1 is a 2 θ scan X-ray diffraction spectrum of a sapphire (001) substrate based piezoelectric film of the present invention;

fig. 2 is an ω -scan X-ray diffraction spectrum of the piezoelectric thin film of the present invention based on a sapphire (001) substrate.

FIG. 3 is a 2 θ scanning X-ray diffraction spectrum of the piezoelectric film of the present invention based on a 4H-SiC (001) substrate;

FIG. 4 is an ω -scan X-ray diffraction spectrum of the piezoelectric film of the present invention based on a 4H-SiC (001) substrate.

FIG. 5 is a schematic structural view of a piezoelectric resonator according to the present invention;

FIG. 6 is a cross-sectional view taken at A-A of FIG. 5;

fig. 7 is a performance test chart of the piezoelectric device according to the present invention.

Reference numerals: 101-foreign substrate, 102-piezoelectric film, 103-signal input electrode, 104-signal output electrode.

Detailed Description

Gallium oxide of the formula Ga₂O₃Is provided withα, β, gamma, and the only phase has piezoelectric property through experimental test and theoretical analysis, compared with AlN which is a piezoelectric film material widely researched and applied at present, the phase gallium oxide has the following characteristics that the piezoelectric coefficient of the phase gallium oxide is only e₃₃＝0.94C/m²Lower than AlN material. On the other hand, however, phase gallium oxide has a relative dielectric constant of only_r3.6, which is significantly lower than the relative dielectric constant of AlN material. The high-efficiency conversion of the externally input alternating current signal into mechanical vibration energy can be ensured, and the defect of phase gallium oxide in the aspect of piezoelectric coefficient is overcome. And because the phase gallium oxide has an ultra-wide forbidden band of 5eV, the phase gallium oxide has good insulativity, can avoid heat loss caused by leakage current in the working process of the piezoelectric device, and improves the energy conversion efficiency of the piezoelectric device. Therefore, considering the comprehensive properties of the materials in three aspects of piezoelectric coefficient, dielectric constant and forbidden band width, the phase gallium oxide can be considered as a novel semiconductor material suitable for preparing high-performance piezoelectric devices. The technical scheme of the invention makes up the blank of phase gallium oxide in the piezoelectric technology.

The specific application of the phase gallium oxide in the piezoelectric material can be produced into a piezoelectric film, for example, by using the following production method: growing a phase gallium oxide piezoelectric film on a foreign substrate, and controlling the preparation temperature to be not higher than 850 ℃, wherein the preparation temperature is preferably not higher than 650 ℃. The thickness of the film is controlled to be 0.1um to 100um, and the preferable thickness is 0.5um to 10 um. Further, the crystal plane of the phase gallium oxide piezoelectric thin film is preferentially oriented to the (001) orientation.

The foreign substrate can be sapphire, 4H-SiC, 6H-SiC, GaAs, InP, Si, SiO₂One of the groups of/Si. Sapphire, 4H-SiC and Si are preferred.

The crystal orientation of the various foreign substrates is preferably sapphire (001), 4H-SiC (001), 6H-SiC (001), GaAs (111), InP (111), Si (111), SiO₂/Si(111)。

The actual crystal orientation of the surface of the heterogeneous substrate has an inclination angle of 0-6 degrees relative to the crystal orientation of the substrate. Preferably, the inclination angle is 0.2-4 degrees.

Optionally, the phase gallium oxide piezoelectric film may be prepared by a method including Metal Organic Chemical Vapor Deposition (MOCVD), spray chemical vapor deposition (Mist-CVD), Halide Vapor Phase Epitaxy (HVPE), plasma chemical vapor deposition (PECVD), magnetron sputtering, and other film preparation methods. Among them, Metal Organic Chemical Vapor Deposition (MOCVD) and magnetron sputtering are preferable.