CN114553178A - Bulk acoustic wave resonator having tungsten electrode, filter, and electronic device - Google Patents

Abstract

The invention relates to a bulk acoustic wave resonator, comprising: a substrate; an acoustic mirror; a bottom electrode; a top electrode; and a piezoelectric layer arranged between the bottom electrode and the top electrode, wherein: the piezoelectric layer is a doped piezoelectric layer layer; and the top electrode and/or the bottom electrode are tungsten electrodes containing metal tungsten. The top electrode and/or the bottom electrode is a single-layer electrode made of metal tungsten or a single-layer electrode made of tungsten alloy. Or the top electrode and/or the bottom electrode are stacked electrodes, the stacked electrodes include at least two stacked electrode layers of different materials, the at least two electrode layers include at least one tungsten electrode layer, and the The tungsten electrode layer is an electrode layer made of metal tungsten or an electrode layer made of tungsten alloy. The present invention also relates to a filter having the above-mentioned resonator and an electronic device having the filter or resonator.

Description

Bulk Acoustic Resonators, Filters, and Electronic Devices with Tungsten Electrodes

technical field

Embodiments of the present invention relate to the field of semiconductors, and in particular, to a bulk acoustic wave resonator, a filter having the resonator, and an electronic device having the resonator or the filter.

Background technique

As the basic elements of electronic equipment, electronic devices have been widely used, and their application scope includes mobile phones, automobiles, home appliances and so on. In addition, technologies such as artificial intelligence, the Internet of Things, and 5G communications that will change the world in the future still need to rely on electronic devices as their foundation.

Electronic devices can play different characteristics and advantages according to different working principles. Among all electronic devices, devices that use the piezoelectric effect (or inverse piezoelectric effect) are one of the most important categories. Piezoelectric devices have a very wide range of application scenarios. . Film Bulk Acoustic Resonator (FBAR for short, also known as Bulk Acoustic Resonator, also known as BAW) as an important member of piezoelectric devices is playing an important role in the field of communication, especially FBAR filter in radio frequency filter The market share in the field is increasing. FBAR has excellent characteristics such as small size, high resonant frequency, high quality factor, large power capacity, and good roll-off effect. Its filters are gradually replacing traditional surface acoustic wave (SAW) filters And ceramic filters, play a huge role in the field of wireless communication radio frequency, its high sensitivity advantage can also be applied to biological, physical, medical and other sensing fields.

A schematic cross-sectional view of a conventional thin film bulk acoustic resonator is shown in Figure 1. In Figure 1, for example, the material of the bottom electrode 30 and the top electrode 50 is molybdenum, and the material of the piezoelectric layer 40 is aluminum nitride. The thicknesses of the bottom electrode 30 and the top electrode 50 are equal to t, and the thickness of the piezoelectric layer 40 is d. The thickness ratio t/d of the thickness of the monolayer electrode and the piezoelectric layer will affect the effective electromechanical coupling coefficient of the resonator, which in turn affects the bandwidth of the resonator (the larger the effective electromechanical coupling coefficient, the larger the bandwidth). In the design of thin-film bulk acoustic wave resonators, the impedance needs to be matched to 50 ohms. Under the same frequency and bandwidth, the thinner the piezoelectric layer is, the smaller the area A of the effective area can be, so that the number of resonators integrated on a single wafer can be reduced. The more, the manufacturing cost can be saved.

The usual method for reducing the thickness of the piezoelectric layer is to use scandium-doped aluminum nitride as the piezoelectric layer to increase the electromechanical coupling coefficient. When the same bandwidth is required, a larger ratio of the thickness of the single-layer electrode to the piezoelectric layer, t/ d, so as to achieve the purpose of reducing the thickness of the piezoelectric layer, matching 50 ohms can reduce the area A of the resonator.

However, the problem brought by the above method is: under the same power density, the reduction of the area will reduce the power capacity of the resonator.

SUMMARY OF THE INVENTION

In order to not only reduce the area of the effective area of the resonator, but also ensure the power capacity of the resonator, for example, in order to solve the power capacity caused by the reduction of the area of the effective area of the resonator after introducing scandium-doped aluminum nitride as the piezoelectric layer The problem of deterioration, the present invention is proposed.

According to an aspect of the embodiments of the present invention, a bulk acoustic wave resonator is proposed, comprising:

base;

acoustic mirror;

bottom electrode;

top electrode; and

a piezoelectric layer, arranged between the bottom electrode and the top electrode,

in:

the piezoelectric layer is a doped piezoelectric layer; and

The top electrode and/or the bottom electrode are tungsten electrodes containing metal tungsten.

Optionally, the top electrode and/or the bottom electrode is a single-layer electrode made of metal tungsten or a single-layer electrode made of tungsten alloy.

Alternatively, the top electrode and/or the bottom electrode are stacked electrodes, the stacked electrodes include at least two stacked electrode layers of different materials, and the at least two electrode layers include at least one layer of tungsten electrodes layer, the tungsten electrode layer is an electrode layer made of metal tungsten or an electrode layer made of tungsten alloy.

Embodiments of the present invention also relate to a filter comprising the above-mentioned bulk acoustic wave resonator.

Embodiments of the present invention also relate to an electronic device comprising the above-mentioned filter or the above-mentioned resonator.

Description of drawings

These and other features and advantages of the various disclosed embodiments of the present invention may be better understood by the following description and accompanying drawings, wherein like reference numerals refer to like parts throughout, wherein:

1 is a schematic cross-sectional view of a conventional thin-film bulk acoustic resonator;

FIG. 2 exemplarily shows the relationship between the ratio of the thickness of the single-layer electrode to the thickness of the piezoelectric layer and the electromechanical coupling coefficient of the resonator in the case where the thicknesses of the top and bottom electrodes are the same, wherein the respective The three cases are that the piezoelectric layer is aluminum nitride, the electrodes are all molybdenum, the piezoelectric layer is scandium-doped aluminum nitride, the electrodes are all molybdenum, the piezoelectric layer is scandium-doped aluminum nitride, and the electrodes are all tungsten;

3-12 respectively illustrate schematic cross-sectional views of bulk acoustic wave resonators according to different embodiments of the present invention.

Detailed ways

The technical solutions of the present invention will be further described in detail below through embodiments and in conjunction with the accompanying drawings. In the specification, the same or similar reference numerals refer to the same or similar parts. The following description of the embodiments of the present invention with reference to the accompanying drawings is intended to explain the general inventive concept of the present invention, and should not be construed as a limitation of the present invention.

As known to those skilled in the art, if a doped piezoelectric layer is used instead of the piezoelectric layer, under the same electromechanical coupling coefficient and frequency, the area of the effective area of the resonator will become smaller, while the area of the effective area of the resonator will become smaller. The smaller the area, the smaller the power capacity of the resonator at the same power density.

Moreover, as known to those skilled in the art, under the same electromechanical coupling coefficient and frequency, if the molybdenum electrode of the resonator is replaced with a tungsten electrode, the area of the effective area of the resonator will become smaller, which is not conducive to maintaining larger power capacity.

In addition, as known to those skilled in the art, the sheet resistivity of metal tungsten at room temperature is 20-30 microohms per centimeter, and the sheet resistivity of metal molybdenum at room temperature is about 10 microohms per centimeter. It can be seen that at room temperature , the film resistivity of metal tungsten is much larger than that of metal molybdenum at room temperature. Therefore, it is generally believed that the resistance of the tungsten electrode with tungsten as the electrode is greater than the resistance of the molybdenum electrode with molybdenum as the electrode during the working process of the resonator, so that the tungsten electrode generates heat due to the current flowing through the resistance compared with the molybdenum electrode. In this case, replacing the molybdenum electrode of the resonator with a tungsten electrode will directly lead to an increase in the heat release of the electrode of the resonator during operation. large power capacity. Therefore, those skilled in the art would not think of replacing the molybdenum electrodes of the resonators with tungsten electrodes based on maintaining a large power capacity.

Based on the above, for resonators using molybdenum electrodes and doped piezoelectric layers (which already have a smaller effective area based on doping), it is common practice for those skilled in the art to try to avoid using molybdenum electrodes and doping The molybdenum electrode in the resonator of the piezoelectric layer is replaced with a tungsten electrode, because the use of a tungsten electrode will further reduce the area of the active area and is not conducive to maintaining a good power capacity.

However, the inventors found that if the molybdenum electrode in the resonator using the molybdenum electrode and the doped piezoelectric layer is replaced with a tungsten electrode, the area of the effective region of the resonator can be reduced, and the power capacity of the resonator can be ensured.

Based on the above, the present invention proposes a technical solution of combining a doped piezoelectric layer (which can reduce the area of the effective area of the resonator) and a tungsten electrode (which can reduce the area of the effective area of the resonator) in a bulk acoustic wave resonator .

The technical solutions of the present invention will be specifically described below with reference to accompanying drawings 2-12. In the present invention, the reference numerals are briefly described as follows:

110, 210, 310: substrate, the optional material is single crystal silicon, quartz, gallium arsenide or sapphire, etc.

120, 220, 320: acoustic mirrors, which are located on the upper surface of the substrate 110 or embedded in the interior of the substrate. In the present invention, the acoustic mirror is formed by a cavity embedded in the substrate, but the acoustic mirror can also be a Bragg reflection layer and other Equivalent form.

130, 230, 240, 330, 340, 350: A single-layer bottom electrode or a bottom electrode layer in a bottom electrode stack, which may be deposited on the upper surface of the acoustic mirror and cover the acoustic mirror. The edge of the bottom electrode 130 can be etched into a bevel, and the bevel is aligned with the edge of the active area of the resonator, and the edge of the bottom electrode 130 can also be stepped, vertical, or other similar structures. The material of the bottom electrode can be: gold (Au), tungsten (W), molybdenum (Mo), platinum (Pt), ruthenium (Ru), iridium (Ir), titanium tungsten (TiW), aluminum (Al), titanium ( Ti), osmium (Os), magnesium (Mg), gold (Au), tungsten (W), molybdenum (Mo), platinum (Pt), ruthenium (Ru), iridium (Ir), germanium (Ge), copper ( Cu), aluminum (Al), chromium (Cr), arsenic-doped gold and other similar metals, as well as alloys of the above metals.

140, 250, 360: piezoelectric thin film layer or piezoelectric layer, which can be selected from aluminum nitride (AlN), zinc oxide (ZnO), lead zirconate titanate (PZT), Lithium niobate (LiNbO ₃ ), quartz (Quartz), potassium niobate (KNbO ₃ ) or lithium tantalate (LiTaO ₃ ) and other materials, doping elements such as scandium (Sc), yttrium (Y), magnesium (Mg), Titanium (Ti), Lanthanum (La), Cerium (Ce), Praseodymium (Pr), Neodymium (Nd), Promethium (Pm), Samarium (Sm), Europium (Eu), Gadolinium (Gd), Terbium (Tb), Dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), etc.

150, 260, 270, 370, 380, 390: a single-layer top electrode or a top electrode layer in a top electrode stack, its material can be: gold (Au), tungsten (W), molybdenum (Mo), platinum ( Pt), Ruthenium (Ru), Iridium (Ir), Titanium Tungsten (TiW), Aluminum (Al), Titanium (Ti), Osmium (Os), Magnesium (Mg), Gold (Au), Tungsten (W), Molybdenum (Mo), platinum (Pt), ruthenium (Ru), iridium (Ir), germanium (Ge), copper (Cu), aluminum (Al), chromium (Cr), arsenic-doped gold and other similar metals, and the above metals alloys, etc. The material of the top electrode and the bottom electrode can be the same or different. In Figure 2, no passivation layer is provided over the top electrode, but as can be appreciated, a passivation layer may also be provided.

160: Passivation layer, the material of the passivation layer includes but not limited to polysilicon SiO ₂ , Si ₃ N ₄ , AlN and the like.

170 : a protruding structure, the material of the protruding structure is the same as the top electrode 130 or the bottom electrode 150 or the piezoelectric layer 140 . The raised structure is located at the edge of the effective area, and the raised structure can reduce the acoustic impedance of the effective area where it is located. In an embodiment of the present invention, the material of the protruding structure is metal tungsten.

A schematic cross-sectional view of the bulk acoustic wave resonator according to the present invention is also shown in FIG. 1 . In a specific example, the material of the bottom electrode 30 and the top electrode 50 of the resonator is molybdenum, and the material of the piezoelectric layer 40 is scandium-doped aluminum nitride. The thicknesses of the bottom electrode 30 and the top electrode 50 are equal to t, and the thickness of the piezoelectric layer 40 is d. The thickness ratio t/d of the monolayer electrode to the thickness of the piezoelectric layer affects the effective electromechanical coupling coefficient of the resonator, which in turn affects the bandwidth of the resonator (the larger the effective electromechanical coupling coefficient, the larger the bandwidth).

FIG. 2 exemplarily shows the relationship between the ratio of the thickness of the single-layer electrode to the thickness of the piezoelectric layer and the electromechanical coupling coefficient of the resonator in the case where the thicknesses of the top and bottom electrodes are the same, wherein the respective The piezoelectric layer is aluminum nitride and the electrodes are all molybdenum, the piezoelectric layer is scandium-doped aluminum nitride and the electrodes are all molybdenum, the piezoelectric layer is scandium-doped aluminum nitride and the electrodes are all tungsten.

As shown in FIG. 2 , assuming the bottom electrode 30 and the top electrode 50 have the same thickness, the abscissa is the thickness ratio t/d of the thickness of the single-layer electrode and the piezoelectric layer, and the ordinate is the effective electromechanical coupling coefficient (Kt ² eff) of the resonator , the solid line is the effective electromechanical coupling coefficient when the bottom electrode and the top electrode are molybdenum, and the piezoelectric layer is aluminum nitride; the dotted line is when the bottom electrode and the top electrode are molybdenum, and the piezoelectric layer is 3% scandium-doped aluminum nitride. The effective electromechanical coupling coefficient, the overall effective electromechanical coupling coefficient curve is improved; the dotted line is the effective electromechanical coupling coefficient when the bottom electrode and the top electrode are tungsten, and the piezoelectric layer is 3% scandium-doped aluminum nitride, and the effective electromechanical coupling coefficient curve is overall further improvement. The traditional bulk acoustic wave resonator uses molybdenum as the electrode. When the piezoelectric layer uses scandium-doped aluminum nitride, at the same frequency, compared with the case where the piezoelectric layer is aluminum nitride, the thickness ratio of the electrode to the piezoelectric layer thickness is t/d Increase the thickness of the electrode, the thickness of the piezoelectric layer becomes thinner, and the area A required for matching to 50 ohms is smaller, which can achieve the purpose of reducing the area A of the effective area to increase the number of resonators, thereby reducing the manufacturing cost, but shrinking This area A will at the same time degrade the power capacity of the resonator.

In the present invention, the tungsten electrode is used instead of the molybdenum electrode. On the one hand, the thermal conductivity of the tungsten electrode (1.73) is greater than that of the molybdenum electrode (1.38), and the thermal conductivity of the tungsten electrode is better. Higher power capacity; on the other hand, the tungsten electrode can further improve the effective electromechanical coupling coefficient. When the effective electromechanical coupling coefficient is the same, the thickness ratio t/d of the thickness of the electrode and the piezoelectric layer can be larger. Compared with the molybdenum electrode, the thickness of the tungsten electrode The increase can reduce the resistance of the film electrode and reduce the heat generation of the electrode resistance, and because the electrode material has better thermal conductivity than the piezoelectric layer material, the resonator can withstand a higher power density and can have a higher power capacity.

Therefore, in the present invention, using a tungsten electrode in a resonator having a scandium-doped aluminum nitride piezoelectric layer can ensure the power capacity of the resonator while reducing the area A of the effective region of the resonator. Scandium-doped aluminum nitride is used as the piezoelectric layer and tungsten is used as the electrode material, which can not only reduce the area of the resonator, make more resonators integrated in a single wafer, but also ensure the power capacity of the resonator, which will not be damaged under high power. .

Various embodiments of the present invention are exemplified below with reference to FIGS. 3-12.

As shown in FIG. 3 , in one embodiment of the present invention, the bottom electrode 130 and the top electrode 150 are tungsten electrodes with the same thickness (t1=t2), and the piezoelectric layer 140 is made of aluminum nitride or other materials with different doping concentrations. Piezoelectric material.

In an optional embodiment, in the structure shown in FIG. 3 , the bottom electrode 130 and the top electrode 150 are tungsten electrodes with different thicknesses (t1>t2 or t1<t2), and the piezoelectric layer 140 has different doping concentrations of aluminum nitride or other piezoelectric materials.

In an optional embodiment, in the structure shown in FIG. 3 , the bottom electrode 130 is a tungsten electrode, the top electrode 150 is a molybdenum electrode or other electrode materials, and the thicknesses of the top electrode and the bottom electrode are the same or different (t1=t2 Or t1>t2 or t1<t2), the piezoelectric layer 140 is made of aluminum nitride or other piezoelectric materials with different doping concentrations.

In an optional embodiment, in the structure shown in FIG. 3 , the bottom electrode 130 is a molybdenum electrode or other electrode materials, and the top electrode 150 is a tungsten electrode, and the thicknesses are the same or different (t1=t2 or t1>t2 or t1 <t2), the piezoelectric layer 140 is made of aluminum nitride or other piezoelectric materials with different doping concentrations.

The structure shown in FIG. 4 is similar to that of FIG. 3, except that in FIG. 4, a passivation layer 160 is added on the top electrode 150.

The structure shown in FIG. 5 is similar to that shown in FIG. 3 , the difference is that in FIG. 5 , a raised structure 170 is added on the top electrode 150 .

The structure shown in FIG. 6 is similar to that shown in FIG. 5 , except that in FIG. 6 , a protruding structure 170 and a passivation layer 160 are added on the top electrode 150 .

In the structures shown in Figs. 3-6, the top electrode or the bottom electrode is a single-layer electrode structure, but the present invention is not limited thereto. The electrodes may also be in a laminated structure, and in this case, one electrode layer in the laminated electrode may be a tungsten electrode layer. Figures 7-12 illustrate embodiments of resonators with stacked electrodes. Here is an example description:

In FIG. 7, the top electrode is composed of a laminated structure of a first top electrode 260 and a second top electrode 270, and the bottom electrode is composed of a laminated structure of a first bottom electrode 240 and a second bottom electrode 230, wherein 260 and 240 are tungsten electrodes, 270 and 230 may be other electrode material layers.

The structure shown in FIG. 8 is similar to that shown in FIG. 7, except that the top electrode in FIG. 8 is only 260, wherein 260 and 240 are tungsten electrodes, and 230 can be other electrode material layers.

The structure shown in Fig. 9 is similar to that of Fig. 7, except that the bottom electrode in Fig. 9 is only 240, wherein 260 and 240 are tungsten electrodes, and 270 can be other electrode material layers.

In FIG. 10 , the top electrode is composed of a stacked structure of the first top electrode 370 , the second top electrode 380 and the third top electrode 390 , and the bottom electrode is composed of the first bottom electrode 350 , the second bottom electrode 340 and the third bottom electrode 330 The layered structure is composed, wherein 370 and 350 are tungsten electrodes, 330, 340, 380 and 390 can be other electrode material layers, and 330 and 390 can still be tungsten electrodes.

The structure shown in Figure 11 is similar to that of Figure 10, except that the top electrode in Figure 11 has only 370, wherein 370 and 350 are tungsten electrodes, 330 and 340 can be other electrode material layers, and 330 can be a tungsten electrode.

The structure shown in Figure 12 is similar to that shown in Figure 10, except that the bottom electrode in Figure 12 is only 240, wherein 370 and 350 are tungsten electrodes, 380 and 390 can be other electrode materials, and 390 can be a tungsten electrode.

In the embodiment shown in Figures 7-12, tungsten electrode layers are provided on both the upper and lower sides of the piezoelectric layer, but the present invention is not limited to this, for example, a tungsten electrode layer may be provided only on one side of the piezoelectric layer.

In the above-mentioned embodiments of the present invention, the tungsten electrode or the tungsten electrode layer is formed with metal tungsten, but the present invention is not limited to this, and the tungsten electrode or the tungsten electrode layer can also be formed by using a tungsten alloy (ie, an alloy containing metal tungsten), which is both within the protection scope of the present invention.

It should be pointed out that, in the present invention, each numerical range, except that it is clearly indicated that it does not include the endpoint value, can be the endpoint value, and can also be the median value of each numerical range, and these are all within the protection scope of the present invention. .

In the present invention, upper and lower are relative to the bottom surface of the base of the resonator. For a component, the side close to the bottom surface is the lower side, and the side away from the bottom surface is the upper side.

In the present invention, inner and outer are relative to the center of the effective area of the resonator (ie, the center of the effective area) in the lateral direction or the radial direction, and one side or one end of a component close to the center of the effective area is the inner side or inner end, and the side or end of the part away from the center of the active area is the outer or outer end. For a reference position, being located inside the position means being between the position and the center of the active area in the lateral or radial direction, and being located outside of the position means being farther from the position in the lateral or radial direction than the position Effective regional center.

As can be appreciated by those skilled in the art, BAW resonators according to the present invention may be used to form filters or electronic devices. The electronic equipment here includes, but is not limited to, intermediate products such as RF front-end, filter and amplifier modules, and terminal products such as mobile phones, WIFI, and drones.

Based on the above, the present invention proposes the following technical solutions:

1. A bulk acoustic wave resonator, comprising:

base;

acoustic mirror;

bottom electrode;

top electrode; and

a piezoelectric layer, arranged between the bottom electrode and the top electrode,

in:

the piezoelectric layer is a doped piezoelectric layer; and

The top electrode and/or the bottom electrode are tungsten electrodes containing metal tungsten.

2. The resonator according to 1, wherein:

The top electrode and/or the bottom electrode is a single-layer electrode made of metal tungsten or a single-layer electrode made of tungsten alloy.

3. The resonator according to 2, wherein:

The top and bottom electrodes are both tungsten electrodes; and

The ratio of the monolayer thickness of the top or bottom electrode to the thickness of the doped piezoelectric layer is in the range of 0.1-1.

4. The resonator according to 2, wherein:

The top electrode and the bottom electrode are both tungsten electrodes;

The non-electrode connecting ends of the bottom electrode are all located outside the boundary of the acoustic mirror in the horizontal direction and are in thermal contact with the substrate.

5. The resonator according to 2, wherein:

One of the top and bottom electrodes is a tungsten electrode, and the other is a non-tungsten electrode, and the thickness of the tungsten electrode is different from the thickness of the non-tungsten electrode; or

One of the top electrode and the bottom electrode is a tungsten electrode, and the other is a non-tungsten electrode, and the thickness of the tungsten electrode is equal to the thickness of the non-tungsten electrode.

6. The resonator according to 1, wherein:

The top electrode and/or the bottom electrode are stacked electrodes, the stacked electrode includes at least two stacked electrode layers of different materials, the at least two electrode layers include at least one tungsten electrode layer, and the tungsten electrode The electrode layer is an electrode layer made of metal tungsten or an electrode layer made of a tungsten alloy.

7. The resonator according to 6, wherein:

The electrode layer adjacent to the piezoelectric layer of the stacked electrode is a first electrode layer, and the first electrode layer is a tungsten electrode layer.

8. The resonator according to 7, wherein:

The top electrode and the bottom electrode are both stacked electrodes.

9. The resonator of 8, wherein:

The non-electrode connecting ends of the bottom electrode are all located outside the boundary of the acoustic mirror in the horizontal direction and are in thermal contact with the substrate.

10. The resonator according to 7, wherein:

One of the top electrode and the bottom electrode is a laminated electrode, and the other is a non-laminated electrode.

11. The resonator of any one of 1-10, wherein:

The piezoelectric layer is scandium-doped aluminum nitride.

12. The resonator of any of 1-10, wherein:

The resonator further includes a protruding structure arranged along the effective area, and the material of the protruding structure is tungsten.

13. A filter comprising the bulk acoustic wave resonator according to any one of 1-12.

14. An electronic device comprising the filter according to 13 or the resonator according to any one of 1-12.

Although embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that changes may be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is determined by It is defined by the appended claims and their equivalents.

Claims (14)

1. A bulk acoustic wave resonator, comprising: base; acoustic mirror; bottom electrode; top electrode; and a piezoelectric layer, arranged between the bottom electrode and the top electrode, in: the piezoelectric layer is a doped piezoelectric layer; and The top electrode and/or the bottom electrode are tungsten electrodes containing metal tungsten. 2. The resonator of claim 1, wherein: The top electrode and/or the bottom electrode is a single-layer electrode made of metal tungsten or a single-layer electrode made of tungsten alloy. 3. The resonator of claim 2, wherein: The top and bottom electrodes are both tungsten electrodes; and The ratio of the monolayer thickness of the top or bottom electrode to the thickness of the doped piezoelectric layer is in the range of 0.1-1. 4. The resonator of claim 2, wherein: The top electrode and the bottom electrode are both tungsten electrodes; The non-electrode connection ends of the bottom electrode are all located outside the boundary of the acoustic mirror in the horizontal direction and form thermal contact with the substrate. 5. The resonator of claim 2, wherein: One of the top and bottom electrodes is a tungsten electrode, and the other is a non-tungsten electrode, and the thickness of the tungsten electrode is different from that of the non-tungsten electrode; or One of the top electrode and the bottom electrode is a tungsten electrode, and the other is a non-tungsten electrode, and the thickness of the tungsten electrode is equal to the thickness of the non-tungsten electrode. 6. The resonator of claim 1, wherein: The top electrode and/or the bottom electrode are stacked electrodes, the stacked electrode includes at least two stacked electrode layers of different materials, the at least two electrode layers include at least one tungsten electrode layer, and the tungsten electrode The electrode layer is an electrode layer made of metal tungsten or an electrode layer made of a tungsten alloy. 7. The resonator of claim 6, wherein: The electrode layer adjacent to the piezoelectric layer of the stacked electrode is a first electrode layer, and the first electrode layer is a tungsten electrode layer. 8. The resonator of claim 7, wherein: The top electrode and the bottom electrode are both stacked electrodes. 9. The resonator of claim 8, wherein: The non-electrode connection ends of the bottom electrode are all located outside the boundary of the acoustic mirror in the horizontal direction and form thermal contact with the substrate. 10. The resonator of claim 7, wherein: One of the top electrode and the bottom electrode is a laminated electrode, and the other is a non-laminated electrode. 11. The resonator of any of claims 1-10, wherein: The piezoelectric layer is scandium-doped aluminum nitride. 12. The resonator of any of claims 1-10, wherein: The resonator further includes a protruding structure arranged along the effective area, and the material of the protruding structure is tungsten. 13. A filter comprising the bulk acoustic wave resonator of any of claims 1-12. 14. An electronic device comprising a filter according to claim 13 or a resonator according to any of claims 1-12.

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