Elastic wave device and module

Abstract

The embodiment of the invention provides an elastic wave device and module. The elastic wave device disclosed by the embodiment of the invention comprises a supporting substrate; the piezoelectric layer is arranged on the supporting substrate; the IDT electrode is located on the side, back on to the supporting substrate, of the piezoelectric layer. Wherein the supporting substrate is made of a polycrystalline material, and the number of the small-angle grain boundaries with the orientation difference angle of 2-15 degrees in the supporting substrate accounts for 1-5% of the total number of the grain boundaries. The elastic wave device provided by the embodiment of the invention can effectively suppress noise and ensure normal filtering through the supporting substrate with a specific small-angle grain boundary proportion.

Description

Technical Field

[0001] The invention relates to the technical field of electronic device processing and manufacturing, and in particular to an elastic wave device and a module. Background Art

[0002] In recent years, with the development of technology, higher performance requirements have been put forward for elastic wave devices such as SAW (surface acoustic wave, surface acoustic wave filter) devices. In some SAW devices, such as TC-SAW (temperature compensated filter), a composite substrate obtained by bonding a piezoelectric layer substrate and a supporting substrate is required. Therefore, in the relevant processes of SAW devices, the design of the supporting substrate is still a key research direction. For example, what material is suitable for making a supporting substrate is also a key issue in the industry. For example, single crystal sapphire also has excellent thermal conductivity and is widely used in the LED industry. However, due to its single crystal characteristics, TC-SAW made of single crystal sapphire has always been affected by noise (Spurious) and cannot filter normally. Therefore, how to design the supporting substrate to slow down the reflection of noise and achieve normal filtering is a problem that needs to be solved. Summary of the invention

[0003] The object of the present invention is to provide an elastic wave device and a module capable of reducing noise.

[0004] An embodiment of the present invention provides an elastic wave device comprising: a supporting substrate; a piezoelectric layer disposed on the supporting substrate; an IDT electrode located on the side of the piezoelectric layer facing away from the supporting substrate; wherein the material of the supporting substrate is a polycrystalline material, and the number of small-angle grain boundaries with an orientation difference angle of 2 to 15° in the supporting substrate accounts for 1 to 5% of the total number of grain boundaries.

[0005] One embodiment of the present invention provides a module including a wiring substrate, a plurality of external connection terminals, an integrated circuit component, an inductor, and a sealing portion, and the elastic wave device described above.

[0006] The above embodiments of the present invention have at least one or more of the following beneficial effects: the supporting substrate with a special grain boundary ratio can effectively reduce the energy of longitudinal wave transmission, thereby effectively slowing down the reflection of noise and achieving normal filtering, and can be applicable to frequency bands above 3.5G. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] The specific implementation modes of the present invention will be described in detail below with reference to the accompanying drawings.

[0008] Figure 1 A structural schematic diagram of a support substrate provided in an embodiment of the present invention.

[0009] Figure 2A microstructure diagram of a measurement area of ​​a support substrate provided in an embodiment of the present invention.

[0010] Figure 3 for Figure 2 IPF coloring diagram.

[0011] Figure 4 for Figure 2 Distribution of misorientation angles at grain boundaries.

[0012] Figure 5 A microstructure diagram of a measurement area of ​​another support substrate provided in an embodiment of the present invention.

[0013] Figure 6 for Figure 5 IPF coloring diagram.

[0014] Figure 7 for Figure 5 Distribution of misorientation angles at grain boundaries.

[0015] Figure 8 A microstructure diagram of a measurement area of ​​another support substrate provided in an embodiment of the present invention.

[0016] Fig. 9 for Figure 8 IPF coloring diagram.

[0017] Fig.10 for Figure 8 Distribution of misorientation angles at grain boundaries.

[0018] Fig.11 A comparison diagram of the noise suppression effect of the support substrate provided by different embodiments of the present invention.

[0019] Fig.12 A schematic structural diagram of a composite substrate provided in an embodiment of the present invention.

[0020] Fig.13 A schematic structural diagram of an electronic device provided in an embodiment of the present invention.

[0021] Fig.14 A schematic structural diagram of another electronic device provided by an embodiment of the present invention.

[0022] Fig.15 A schematic structural diagram of another electronic device provided by an embodiment of the present invention.

[0023] Fig.16 A schematic structural diagram of yet another electronic device provided by an embodiment of the present invention.

[0024] Fig.17A schematic diagram of the structure of a module provided in an embodiment of the present invention.

[0025] [Description of Reference Numerals]

[0026] 1000, module; 100, electronic device; 10, composite substrate; 11, supporting substrate; 111, main supporting surface; 112, back surface; 113, side surface; 12, piezoelectric layer; 121, main surface; 13, intermediate layer; 20, electrode; 21, IDT electrode; 22, electrode pad; 30, packaging substrate; 41, first sealing structure; 42, second sealing structure; 51, bump; 52, first conductive portion; 53, first external terminal electrode; 54, second conductive portion; 55, second external terminal electrode; 60, gap; 70, cover; 400, inductor; 500, sealing portion; 600, integrated circuit component; 700, wiring substrate; 701, external connection terminal. DETAILED DESCRIPTION

[0027] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0028] In order to enable those skilled in the art to better understand the technical solution of the present invention, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work should fall within the scope of protection of the present invention.

[0029] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0030] It should also be noted that the division of multiple embodiments in the present invention is only for the convenience of description and should not constitute a special limitation. The features in various embodiments can be combined and referenced to each other without contradiction.

[0031] like Figure 1 As shown, an embodiment of the present invention provides a support substrate 11. The material of the support substrate 11 is a polycrystalline material, and the multiple grains in the support substrate 11 have different crystal orientations and are connected to each other through grain boundaries, that is, the grain boundary is the interface between the grains. The angle between the crystal orientations of any two adjacent grains is the misorientation angle, and the corresponding grain boundaries can be divided into small-angle grain boundaries and non-small-angle grain boundaries by the value of the misorientation angle, wherein the grain boundaries with misorientation angles of 2° to 15° are called small-angle grain boundaries, and the grain boundaries with misorientation angles greater than 15° and the grain boundaries with misorientation angles less than 2° are collectively referred to as non-small-angle grain boundaries. In the support substrate 11 provided in the embodiment of the present invention, the proportion of the number of small-angle grain boundaries to the total number of grain boundaries (referred to as the proportion of small-angle grain boundaries) is 1 to 5%, for example, it can be 1%, 2%, 3%, 4%, etc., and the corresponding non-small-angle grain boundaries (including those with misorientation angles less than 2° and greater than 15°) account for 95 to 99% of the total number of grain boundaries (referred to as the proportion of non-small-angle grain boundaries). For example, the proportion of small-angle grain boundaries is 2%, and the proportion of non-small-angle grain boundaries is 98%. For example, the proportion of small-angle grain boundaries is 3%, and the proportion of non-small-angle grain boundaries is 97%. Of course, the above is only an example, and this embodiment is not limited thereto.

[0032] The polycrystalline material is, for example, any one of polycrystalline magnesium aluminum spinel, polycrystalline sapphire, polycrystalline aluminum nitride, polycrystalline magnesium oxide, and polycrystalline quartz.

[0033] Among them, the value of the misorientation angle of the grain boundary and the number of grain boundaries in the support substrate 11 can be obtained by using the electron backscatter diffraction (EBSD) technology to obtain the microstructure diagram on the support substrate 11 and perform IPF coloring (Inverse Pole Figure coloring) on ​​the microstructure on the support substrate 11. IPF coloring is a method used in materials science to characterize crystal orientation. It represents the orientation information of the crystal in the form of color on a polar coordinate diagram, so that the observer can intuitively identify the texture characteristics of the crystal.

[0034] It is found through experiments that the supporting substrate 11 with a special grain boundary ratio provided by the embodiment of the present invention can effectively reduce the energy of longitudinal wave transmission, thereby effectively slowing down the reflection of noise and achieving normal filtering, and can be applicable to frequency bands above 3.5G.

[0035] Among them, refer to Figure 1 The supporting substrate 11, for example, has a main supporting surface 111, a back surface 112 opposite to the main supporting surface 111, and a side surface 113 located between the main supporting surface 111 and the back surface 112. The main supporting surface 111 can be used to support the piezoelectric layer.

[0036] Specifically, in some embodiments, the number of small-angle grain boundaries in the transverse section or transverse surface of the support substrate 11 accounts for 1-5% of the total number of grain boundaries. More specifically, the proportion of small-angle grain boundaries in the transverse section or transverse surface of the support substrate 11 may be 3-4%. The transverse section may be any section on the support substrate 11 parallel to the main support surface 111, i.e., from Figure 1 The surface obtained after cutting at the position indicated by the dotted line AA in the figure, or at any position parallel to the dotted line AA between the main support surface 111 and the back surface 112, for example, the support substrate 11 is cut into two layers from the dotted line AA, the main support surface 111 is called the upper half layer, and the back surface 112 is called the lower half layer. After cutting, the lower surface of the upper half layer and the upper surface of the lower half layer are both transverse sections. The transverse surface is the main support surface 111 or other surfaces parallel to the main support surface 111, for example, the back surface 112 is parallel to the main support surface 111, and the transverse surface can be the back surface 112. That is, in some embodiments, the proportion of small-angle grain boundaries on the main support surface 111 in the support substrate 11 is 1-5%. In some embodiments, the proportion of small-angle grain boundaries on the back surface 112 in the support substrate 11 is 1-5%. In some embodiments, the proportion of small-angle grain boundaries in any cross section parallel to the main support surface 111 in the support substrate 11 is 1-5%.

[0037] In some embodiments, the number of small-angle grain boundaries on any surface of the support substrate 11 (i.e., any of the main support surface 111, the back surface 112, and the side surface 113) accounts for 1-5% of the total number of grain boundaries. That is, when observing the grain boundaries on any surface of the support substrate 11, the number of small-angle grain boundaries accounts for 1-5%.

[0038] More specifically, the number of small-angle grain boundaries on any surface of the support substrate 11 accounts for 3-4% of the total number of grain boundaries, which can achieve a better effect of reducing noise. Fig.11 , Fig.11 The noise in the support substrate 11 of the present application of the single crystal sapphire substrate is compared. Fig.11 #1 is a sapphire substrate, #2, #3 and #4 are support substrates 11 provided by the present application, the grain size of #2 is 20-30 μm, and the small-angle grain boundary accounts for 3.2%. The grain size of #3 is 15-20 μm, and the small-angle grain boundary accounts for 3.5%. The grain size of #4 is 5-10 μm, and the small-angle grain boundary accounts for 3.7%. Fig.11 The horizontal axis is Frequency (MHz), the vertical axis is admittance (dB), and the gray dotted arrow indicates the frequency boundary of 1600MHz. Fig.11It can be seen that the noise with a small-angle grain boundary ratio between 3.2% and 3.7% meets the use requirements, and the effect of suppressing noise is best when the small-angle grain boundary ratio is 3.7%.

[0039] In some embodiments, in any measurement area on any surface of the support substrate 11, the number of small-angle grain boundaries is greater than or equal to 5, wherein the measurement area is an area with a length of 150 μm (micrometers) and a width of 150 μm. That is, a 150 μm*150 μm area is randomly selected on any surface of the support substrate 11 for observation, and the number of small-angle grain boundaries observed is greater than or equal to 5.

[0040] like Figure 2 and Figure 3 As shown, Figure 2 An image of the microstructure of a measurement area on a lateral surface of a support substrate 11 (made of polycrystalline magnesium aluminum spinel) provided in this embodiment, Figure 3 For Figure 2 The image processed by IPF coloring is Figure 3 In the figure, the colored ones are the grains, and the outlines of the grains are the grain boundaries. Figure 3 The closer the colors of two adjacent grains are, the smaller the misorientation angle corresponding to the grain boundary between the two grains is. Figure 2 The small-angle grain boundaries are marked with red lines. Figure 2 The number of small-angle grain boundaries shown in FIG. 6 is 6.

[0041] In some embodiments, the grain size of the crystal grains in the support substrate 11 is 1 to 100 micrometers. Figure 2 and Figure 3 In the figure shown, the particle size of the grains is 10 to 100 microns. For example, the supporting substrate 11 has grains of different sizes such as 10 microns, 25 microns, 40 microns, 50 microns, 60 microns, and 100 microns, and the particle size of the smallest grain is not less than 10 microns (≥10μm), and the particle size of the largest grain does not exceed 100 microns (≤100μm).

[0042] In a further embodiment, the grain size of the supporting substrate 11 is 5 to 60 microns. For example, the supporting substrate 11 has grains of different sizes such as 5 microns, 10 microns, 20 microns, 25 microns, 40 microns, and 60 microns, and the grain size of the smallest grain is not less than 5 microns (≥5μm), and the grain size of the largest grain is not more than 60 microns (≤60μm). Then, the number of small-angle grain boundaries in any measurement area on any surface of the supporting substrate 11 is greater than or equal to 25. That is, in the supporting substrate 11 with a grain size of 5 to 60 microns, any 150 micron*150 micron area can be observed, and the number of small-angle grain boundaries can be observed to be greater than or equal to 25. Figure 5 and Figure 6 , Figure 5 It is an image of the microstructure of a region of 150 microns*150 microns in a certain lateral surface of a support substrate 11 (the material is polycrystalline magnesium aluminum spinel) with a grain size of 5 to 60 microns. Figure 6 To adopt Figure 5 The image in the middle area is processed by IPF coloring method. Figure 6 The closer the colors of two adjacent grains are, the smaller the misorientation angle corresponding to the grain boundary between the two adjacent grains is. Figure 5 The red lines mark the small-angle grain boundaries. Figure 5 The number of obvious small-angle grain boundaries is more than 25.

[0043] In another embodiment, the grain size of the supporting substrate 11 is 1 to 5 microns. For example, the supporting substrate 11 has grains of different sizes such as 1 micron, 2 microns, 3 microns, and 5 microns, and the grain size of the smallest grain is not less than 5 microns (≥5μm), and the grain size of the largest grain is not more than 60 microns (≤60μm). Then, the number of small-angle grain boundaries in any measurement area on any surface of the supporting substrate 11 is greater than or equal to 40. That is, if an area of ​​150 microns*150 microns is randomly selected for observation on any surface of the supporting substrate 11, the number of small-angle grain boundaries observed is greater than or equal to 40. Figure 8 and Fig. 9 , Figure 8 It is an image of the microstructure of a region of 150*150 μm in a lateral surface of a support substrate 11 (the material is polycrystalline magnesium aluminum spinel) with a grain size of 1 to 5 μm. Fig. 9 yes Figure 8 The image in the middle area is processed by IPF coloring method. Fig. 9 The closer the colors of two adjacent grains are, the smaller the misorientation angle corresponding to the grain boundary between the two adjacent grains is. Figure 8 The red lines mark the small-angle grain boundaries. Figure 8The number of obvious small-angle grain boundaries is more than 40.

[0044] In some embodiments, in any measurement area on any surface of the support substrate 11, the number of small-angle grain boundaries accounts for 1-5% of the total number of grain boundaries. That is, if an area of ​​150 microns * 150 microns is randomly selected for observation on any surface of the support substrate 11, the proportion of small-angle grain boundaries observed is within the range of 1-5%. In other words, not only does the support substrate 11 have a specific proportion of small-angle grain boundaries, but the distribution of small-angle grain boundaries is also uniform, which has a better effect of suppressing noise. More specifically, in any measurement area on any surface of the support substrate 11, the number of small-angle grain boundaries accounts for 3-4% of the total number of grain boundaries. For example, according to Figure 2 and Figure 3 The measured proportion of small-angle grain boundaries is 3.2%, and the proportion of non-small-angle grain boundaries is 96.8%. Figure 5 and Figure 6 The measured proportion of small-angle grain boundaries is 3.45%, and the proportion of non-small-angle grain boundaries is 96.55%. Figure 8 and Fig. 9 The measured proportion of small-angle grain boundaries is 3.7%, and the proportion of non-small-angle grain boundaries is 96.3%. In the above embodiments, the proportion of small-angle grain boundaries is in the range of 3-4%.

[0045] In some embodiments, the distribution peak of the misorientation angle in the support substrate 11 is 30 to 60°. In a more specific embodiment, the distribution peak of the misorientation angle is 40 to 50°. The distribution peak of the misorientation angle means that the number of grain boundaries on the support substrate 11 with the misorientation angle of the distribution peak accounts for the largest proportion of the total number of grain boundaries. For example, the grain boundaries on the support substrate 11 with the misorientation angle of 45° account for the largest proportion of the total number of grain boundaries, and the distribution peak of the orientation angle is 35°. Figure 4 for Figure 2 and Figure 3 Distribution data of misorientation angle in the measurement area shown, Figure 7 for Figure 5 and Figure 6 Distribution data of misorientation angles within the shown metrology area. Fig.10 for Figure 8 and Fig. 9 Distribution data of misorientation angles within the shown metrology area. Figure 4 , Figure 7 and Fig.10 In the equation, the horizontal axis is the value of the misorientation angle, and the vertical axis is the relative frequency of the misorientation angle corresponding to the value of the horizontal axis. The relative frequency is the proportion of the grain boundary with this misorientation angle in the total number of grain boundaries. For a certain coordinate point, the higher the vertical axis value is, the more grain boundaries there are with the misorientation angle corresponding to the horizontal axis value of this point. Figure 4 The misorientation angle corresponding to the middle peak is about 46°, indicating Figure 2 and Figure 3 In the measured area shown, the grain boundaries with misorientation angles of about 46° are the most numerous. Figure 7 The misorientation angle corresponding to the middle peak is about 45°, indicating Figure 2 and Figure 3 In the measured area shown, the grain boundaries with misorientation angles of about 45° are the most numerous. Fig.10 The misorientation angle corresponding to the middle peak is about 45°, indicating Figure 2 and Figure 3 In the measured area shown, the grain boundaries with misorientation angles of about 45° are the most numerous.

[0046] Hereinafter, magnesium aluminum spinel is taken as an example to illustrate the method for preparing the support substrate 11 provided in the embodiment of the present invention.

[0047] S1: Select magnesium aluminum spinel powder for particle size screening to select powder with target particle size;

[0048] S2: CIP (Cold Isostatic Pressing) is performed to press the powder into a blank;

[0049] S3: performing HIP (Hot Isostatic Pressing) operation on the magnesium-aluminum spinel blank, and obtaining a formed magnesium-aluminum spinel ingot after HIP (at this time, the grain boundary ratio has been formed);

[0050] S4: performing multi-wire cutting on the magnesium-aluminum spinel ingot to obtain a spinel cutting substrate, and performing grinding processing on the substrate.

[0051] S5: Polishing the spinel ground substrate produced in S4 to obtain a supporting substrate 11.

[0052] Wherein, the target particle size in step S1 is, for example, 0.1 μm to 100 μm. In step S2, the temperature of the CIP treatment is 1400 to 1500°C, and the pressing pressure is 10000 to 100000 Psi (pounds per square inch). In step S3, the temperature of the HIP treatment is 1650 to 1850°C, and the ambient pressure is 150 to 250 MPa. In step S4, the thickness of the cut substrate is, for example, 250 to 350 μm, and the grinding is preferably 1200 to 1500 # (mesh) silicon carbide or boron carbide powder. The polished surface in step S5 is the surface for bonding with the piezoelectric layer. The roughness of the support substrate surface (i.e., the main support surface 111) obtained in step S5 is Sa≤0.6nm, TTV≤2μm, and the final finished thickness of the spinel substrate (i.e., the support substrate 11) is 200 to 250 μm.

[0053] Reference Fig.12The embodiment of the present invention further provides a composite substrate 10, which includes a piezoelectric layer 12 and the supporting substrate 11 described in the aforementioned embodiment, wherein the piezoelectric layer 12 is disposed on the supporting substrate 11. In some embodiments, the piezoelectric layer 12 and the supporting substrate 11 are bonded to each other, and specifically, the piezoelectric layer 12 is bonded to the main supporting surface 111 of the supporting substrate 11. The two can be directly bonded by van der Waals forces. The piezoelectric layer 12 can be, for example, lithium tantalate or lithium niobate material. The composite substrate 10 uses the aforementioned supporting substrate 11, and has at least the same noise suppression effect as the aforementioned supporting substrate. Fig.13 The embodiment of the present invention further provides an electronic device 100, comprising the supporting substrate 11 in the aforementioned embodiment or the composite substrate 10 in the aforementioned embodiment. In the composite substrate 10, the piezoelectric layer 12, for example, comprises a main surface 121 facing away from the supporting substrate 11, and the electronic device 100, for example, further comprises an electrode 20 disposed on the main surface 121, and the electrode 20, for example, comprises an IDT electrode 21, where IDT is an interdigital transducer, and the electronic device 100 is, for example, a SAW device. The electronic device 100 has the supporting substrate 11 in the aforementioned embodiment, and has the same noise suppression effect as the supporting substrate 11.

[0054] Reference Fig.14 In another embodiment of the present invention, the electronic device 100 (composite substrate 10) further includes an intermediate layer 13, and the intermediate layer 13 is located between the piezoelectric layer 12 and the supporting substrate 11. The acoustic velocity of the intermediate layer 13 is lower than the acoustic velocity of the piezoelectric layer 12. That is, compared with the body wave propagating in the piezoelectric layer 12, the acoustic velocity of the body wave in the intermediate layer 13 is lower. In this embodiment, by providing an intermediate layer 13 with a low acoustic velocity, the acoustic velocity of the elastic wave can be reduced, and the energy of the elastic wave can be concentrated in the medium with a low acoustic velocity (i.e., the intermediate layer 13), which can reduce the loss and improve the Q value.

[0055] The material of the intermediate layer 13 is silicon oxide, silicon oxynitride, tantalum oxide, or any one of the materials with these materials as the main components. In some embodiments, the intermediate layer is made of silicon oxide, and the material of the piezoelectric layer 12 is lithium tantalate. The elastic constant of lithium tantalate has a negative temperature characteristic, while silicon dioxide has a positive temperature characteristic, thereby reducing the absolute value of the TCF (temperature drift coefficient) of the elastic wave device. Furthermore, the inherent acoustic impedance of silicon oxide is less than the inherent acoustic impedance of lithium tantalate, so the electromechanical coupling coefficient of the electronic component can be increased.

[0056] In some embodiments, the thickness of the intermediate layer 13 is greater than or equal to 0.5λ, where λ is the wavelength of the elastic wave determined by the electrode period of the IDT electrode 21. Specifically, the thickness of the intermediate layer 13 can be 0.6 to 0.8λ. In some embodiments, the thickness of the piezoelectric layer 12 is less than or equal to 2λ. Specifically, the thickness of the piezoelectric layer 12 can be less than 1λ. In a specific embodiment, λ is 2.25 microns, the piezoelectric layer 12 is 0.1λ to 1λ, and the thickness of the intermediate layer 13 is 0.6λ.

[0057] The electronic device 100 provided in this embodiment may be packaged in a CSP (Chip Scale Package) or a WLP (Wafer Level Package) package.

[0058] For example, refer to Fig.15 , which is a structural schematic diagram of an electronic device 100 using CSP packaging. The electronic device 100 includes a component (including a composite substrate 10 and an electrode 20), a packaging substrate 30, a first sealing structure 41 and a first external terminal electrode 53. The packaging substrate 30 is arranged opposite to the surface where the electrode 20 of the component is located (that is, the main surface 121 of the piezoelectric layer 12), and a gap 60 is formed between the packaging substrate 30 and the main surface 121. The first sealing structure 41 is arranged on the side of the packaging substrate 30 facing the component, covering the side of the component and the side facing away from the packaging substrate 30 to seal the gap 60 and seal the component. The electrode 20 includes an electrode pad 22 electrically connected to the IDT electrode 21, and the electrode pad 22 is electrically connected to the first conductive portion 52 in the wiring pattern on the packaging substrate 30 through the bump 51. The first conductive portion 52 is electrically connected to the first external terminal electrode 53 on the side of the packaging substrate 30 facing away from the component, so that the electronic device 100 can be electrically connected to an external device through the first external terminal electrode 53.

[0059] Among them, the materials of the packaging substrate 30 and the first sealing structure 41 can refer to the common substrate materials and sealing materials in the existing CSP packaging. The electrode pad 22, the bump 51, the first conductive part 52 and the first external terminal electrode 53 are all made of materials with good conductive properties. This embodiment is not limited to the above examples.

[0060] Reference Fig.16, which is a structural schematic diagram of an electronic device 100 using CSP packaging. The electronic device 100 includes a component (including a composite substrate 10 and an electrode 20), a cover 70, a second sealing structure 42, and a second external terminal electrode. The cover 70 is arranged opposite to a side of the component on which the electrode 20 is arranged (that is, the main surface 121 of the piezoelectric layer 12), and a gap 60 is formed between the cover 70 and the main surface 121. The electrode 20 includes an electrode pad 22 electrically connected to the IDT electrode 21. The area on the main surface 121 where the IDT electrode 21 is arranged is called an effective area. The second sealing structure 42 is arranged between the cover 70 and the component and is arranged around the effective area. The second sealing structure 42 surrounds the electrode pad 22 to achieve sealing of the component. The second external terminal electrode 55 arranged on the surface of the cover 70 facing away from the component is connected to the electrode pad 22 through the second conductive portion 54 that penetrates the cover 70 and the second sealing structure 42, so that the electronic device 100 can be electrically connected to an external device through the second external terminal electrode 55.

[0061] The materials of the cover 70 and the second sealing structure 42 can refer to the cover material and sealing material used in the existing WLP package. The electrode pad 22, the second conductive portion 54 and the second external terminal electrode 55 are all made of materials with good conductive properties, which is not limited in this embodiment. Fig.17 The invention also provides a module 1000, including a wiring substrate 700, a plurality of external connection terminals 701, an integrated circuit component 600, an electronic device 100 (including a composite substrate 10), an inductor 400 and a sealing portion 500. A plurality of external connection terminals 701 are formed on one surface of the wiring substrate 700, and the plurality of external connection terminals 701 are mounted on a motherboard of a pre-set mobile communication terminal. The integrated circuit component 600 (which may be referred to as an IC) is mounted inside the wiring substrate 700. The integrated circuit component 600 includes a switching circuit and a noise amplifier. The electronic device 100 is mounted on the main surface of the wiring substrate 700. The inductor 400 is used for impedance matching, and for example, the inductor 400 is an integrated passive device (IPD: Integrated Passive Device). The sealing portion 500 is used to seal a plurality of electronic components including the electronic device 100 on the wiring substrate 700.

[0062] The module 1000 provided in this embodiment includes the electronic device 100 , that is, includes the supporting substrate 11 , and has the same noise suppression effect as the supporting substrate 11 , which will not be described in detail herein.

[0063] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with this profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. An elastic wave device, characterized in that: include: A supporting substrate; A piezoelectric layer is disposed on the supporting substrate; An IDT electrode is located on a side of the piezoelectric layer facing away from the supporting substrate; Wherein, the material of the support substrate is a polycrystalline material, and the number of small-angle grain boundaries with an orientation difference angle of 2 to 15° in the support substrate accounts for 1 to 5% of the total number of grain boundaries.

2. The elastic wave device according to claim 1, wherein: The supporting substrate has a main supporting surface facing the piezoelectric layer, the number of the small-angle grain boundaries in the transverse cross-section or transverse surface of the supporting substrate accounts for 1 to 5% of the total number of grain boundaries, the transverse surface is the main supporting surface or is parallel to the main supporting surface; the transverse cross-section is parallel to the main supporting surface.

3. The elastic wave device according to claim 1, wherein: The number of the low-angle grain boundaries on any surface of the support substrate accounts for 1 to 5% of the total number of the grain boundaries.

4. The elastic wave device according to claim 1, wherein: In any measurement area on any surface of the support substrate, the number of the low-angle grain boundaries is greater than or equal to 5, and the measurement area is an area with a length of 150 microns and a width of 150 microns.

5. The elastic wave device according to claim 4, characterized in that: The grain size of the crystal grains in the support substrate is 5 to 60 micrometers, and the number of the low-angle grain boundaries in any one of the measurement areas on any surface of the support substrate is greater than or equal to 25.

6. The elastic wave device according to claim 4, wherein: The grain size of the crystal grains in the support substrate is 1 to 5 micrometers, and the number of the low-angle grain boundaries in any one of the measurement areas on any surface of the support substrate is greater than or equal to 40.

7. The elastic wave device according to claim 1, wherein: The number of the low-angle grain boundaries in the support substrate accounts for 3-4% of the total number of the grain boundaries.

8. The elastic wave device according to claim 1, wherein: The distribution peak value of the orientation difference angle in the supporting substrate is 30 to 60 degrees.

9. The elastic wave device according to any one of claims 1 to 8, wherein: The polycrystalline material is any one of polycrystalline magnesium aluminum spinel, polycrystalline sapphire, polycrystalline aluminum nitride, polycrystalline magnesium oxide, and polycrystalline quartz.

10. A module, characterized in that: The invention comprises a wiring substrate, a plurality of external connection terminals, an integrated circuit component, an inductor, and a sealing portion, and the elastic wave device according to any one of claims 1 to 9.

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