Elastic wave device

Abstract

To suppress an increase in size of a device.SOLUTION: An acoustic wave device 100 includes: a support substrate 10; an acoustic wave element 50 provided on one surface of the support substrate 10; wiring 20 provided on the one surface of the support substrate 10, the wiring being electrically connected to the acoustic wave element 50; an input terminal 14a and a ground terminal 14c provided on the other surface of the support substrate 10; via wiring 16a provided in the support substrate 10, the via wiring connecting the wiring 20 with the input terminal 14a and the ground terminal 14c; a frame body 18 provided on the one surface of the support substrate 10 along the edge of the support substrate 10, the frame body surrounding the acoustic wave element 50 and the wiring 20 in plan view; and an inductor L1 formed by a line pattern 30a that is provided along the frame body 18 on the one surface of the support substrate 10 in plan view to be located between the edge of the support substrate 10, and the acoustic wave element 50 and the wiring 20, the inductor being electrically connected to the acoustic wave element 50, and the input terminal 14a and the ground terminal 14c.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to acoustic wave devices. [Background technology]

[0002] 2. Description of the Related Art There is known an acoustic wave device in which a lid is provided on a frame that surrounds an acoustic wave element, and the acoustic wave element is sealed in a gap between the lid and a substrate (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-152612 A Summary of the Invention [Problem to be solved by the invention]

[0004] In order to improve the characteristics of an acoustic wave device, a passive element may be connected to the acoustic wave element, but even when a passive element is connected to the acoustic wave element, it is undesirable for the device to become large in size.

[0005] The present invention has been made in consideration of the above problems, and has an object to prevent the device from becoming large. [Means for solving the problem]

[0006] The present invention relates to a substrate and a The piezoelectric layer includes an electrode provided on the piezoelectric layer. an elastic wave element, wiring provided on the one surface of the substrate and electrically connected to the elastic wave element, a terminal provided on the other surface of the substrate, an element via wiring provided in the substrate and connecting the wiring and the terminal, and a via wiring provided on the one surface of the substrate along an edge of the substrate, The piezoelectric layer. The acoustic wave element anda lid that is provided on the frame with a gap between the frame and the substrate and seals the acoustic wave element in the gap; and a lid that is located on the one surface of the substrate between an end of the substrate and the acoustic wave element and the wiring when viewed from above. Overlapped on the frame The acoustic wave device is formed by one or more line patterns provided along the frame body, and includes the acoustic wave element and a passive element electrically connected to the terminal.

[0009] In the above configuration, the one or more line patterns may be embedded in a recess formed on the one surface of the substrate.

[0010] In the above configuration, an insulating film may be provided between the metal frame and the one or more line patterns, for electrically insulating the frame and the one or more line patterns.

[0011] In the above configuration, a plurality of the terminals are provided on the other surface of the substrate, and the one or more line patterns are a line pattern having one end connected to a first terminal of the plurality of terminals and the other end connected to a second terminal of the plurality of terminals, and the passive element can be an inductor formed by the one line pattern.

[0012] In the above configuration, the substrate may include a first via wiring that is provided on the substrate, connects one end of the one line pattern to the first terminal, and overlaps the frame body in a planar view, and a second via wiring that is provided on the substrate, connects the other end of the one line pattern to the second terminal, and overlaps the frame body in a planar view.

[0013] The aforementioned configuration may further include a third via wiring provided on the substrate, the third via wiring connecting the frame and a ground terminal of the plurality of terminals.

[0014] In the above configuration, a plurality of the wirings and a plurality of the element via wirings are provided on the substrate, and the plurality of element via wirings include a first via wiring that connects a first wiring of the plurality of wirings to the first terminal and overlaps the first wiring in a planar view, and a second via wiring that connects a second wiring of the plurality of wirings to the second terminal and overlaps the second wiring in a planar view, and one end of the one line pattern is connected to the first wiring on the one surface of the substrate, thereby connecting to the first terminal via the first wiring and the first via wiring, and the other end of the one line pattern is connected to the second wiring on the one surface of the substrate, thereby connecting to the second terminal via the second wiring and the second via wiring.

[0015] In the above configuration, the one line pattern may be a meandering line pattern provided meandering in at least one of a thickness direction of the substrate and a direction toward the one surface of the substrate.

[0016] In the above configuration, the one or more line patterns may be two line patterns, and the passive element may be a capacitor in which the two line patterns face each other.

[0017] In the above configuration, a filter may be formed by a plurality of the acoustic wave elements.

[0018] In the above configuration, a multiplexer may be formed by the filter. Effect of the Invention

[0019] According to the present invention, it is possible to prevent the device from becoming large. [Brief description of the drawings]

[0020] [Figure 1] FIG. 1 is a circuit diagram of an acoustic wave device in accordance with a first embodiment. [Diagram 2]FIG. 2 is a plan view of the acoustic wave device in accordance with the first embodiment. [Diagram 3] 3(a) is a cross-sectional view taken along line AA in FIG. 2, and FIG. 3(b) is a cross-sectional view taken along line BB in FIG. [Figure 4] FIG. 4 is a plan view of the acoustic wave device in accordance with the first embodiment. [Diagram 5] 5(a) to 5(d) are cross-sectional views (part 1) illustrating a method for manufacturing the acoustic wave device in accordance with the first embodiment. [Figure 6] 6(a) to 6(c) are cross-sectional views (part 2) illustrating a method for manufacturing the acoustic wave device in accordance with the first embodiment. [Figure 7] FIG. 7 is a plan view of an acoustic wave device according to a comparative example mounted on a wiring board. [Figure 8] FIG. 8 is a plan view of the acoustic wave device in accordance with the first embodiment mounted on a wiring board. [Figure 9] FIG. 9 is a cross-sectional view of an acoustic wave device in accordance with the second embodiment. [Figure 10] FIG. 10 is a plan view of an acoustic wave device in accordance with a first modification of the second embodiment. [Figure 11] 11A and 11B are see-through perspective views of the vicinity of wiring of an acoustic wave device in accordance with a second modification of the second embodiment. [Figure 12] 12(a) and 12(b) are cross-sectional views of an acoustic wave device in accordance with the third embodiment. [Figure 13] FIG. 13 is a plan view of an acoustic wave device in accordance with a fourth embodiment. [Figure 14] 14(a) is a cross-sectional view taken along line AA in FIG. 13, and FIG. 14(b) is a cross-sectional view taken along line BB in FIG. [Figure 15] FIG. 15 is a plan view of an acoustic wave device in accordance with a fifth embodiment. [Figure 16] 16(a) is a cross-sectional view taken along line AA in FIG. 15, and FIG. 16(b) is a cross-sectional view taken along line BB in FIG. [Figure 17] Sixth Example FIG. 17 is a plan view of an acoustic wave device in accordance with a sixth example. [Figure 18]18(a) is a cross-sectional view taken along line AA in FIG. 17, and FIG. 18(b) is a cross-sectional view taken along line BB in FIG. [Figure 19] FIG. 19 is a cross-sectional view of an acoustic wave device in accordance with the seventh embodiment. [Figure 20] FIG. 20 is a cross-sectional view of an acoustic wave device in accordance with the eighth embodiment. [Figure 21] FIG. 21 is a block diagram showing an example of a multiplexer. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS EXAMPLES

[0021] FIG. 1 is a circuit diagram of an acoustic wave device 100 according to a first embodiment. As shown in FIG. 1, the acoustic wave device 100 includes one or more series resonators S1 to S6, one or more parallel resonators P1 to P5, and inductors L1 and L2. The one or more series resonators S1 to S6 are connected in series between an input terminal Tin and an output terminal Tout. The one or more parallel resonators P1 to P5 are connected in parallel between an input terminal Tin and an output terminal Tout. The inductor L1 is connected between a node between the input terminal Tin and the series resonator S1 and the ground. The inductor L2 is connected between a node between the output terminal Tout and the series resonator S6 and the ground. In this manner, the acoustic wave device 100 is a ladder filter.

[0022] The inductors L1 and L2 are provided to adjust the characteristics of the acoustic wave device 100. For example, the inductors L1 and L2 are provided for impedance matching of the acoustic wave device 100.

[0023] FIG. 2 is a plan view of the acoustic wave device 100 according to the first embodiment. FIG. 3(a) is a cross-sectional view taken along line AA in FIG. 2, and FIG. 3(b) is a cross-sectional view taken along line BB in FIG. 2. FIG. 2 mainly illustrates the support substrate 10, the piezoelectric layer 12, the via wirings 16a to 16c, the frame 18, the wiring 20, and the acoustic wave element 50 through the lid 22, and also illustrates line patterns 30a and 30b through a portion of the frame 18. FIG. 2 also illustrates the input terminal 14a, the output terminal 14b, and the ground terminal 14c provided on the lower surface of the support substrate 10 with dashed lines. Note that in FIG. 2, the wiring 20 and the line patterns 30a and 30b are hatched for clarity.

[0024] As shown in Fig. 2, Fig. 3(a) and Fig. 3(b), the acoustic wave device 100 has a piezoelectric layer 12 bonded to the upper surface of a support substrate 10. The support substrate 10 is, for example, a sapphire substrate, an alumina substrate, a spinel substrate, a quartz substrate, a crystal substrate or a silicon substrate, and has a thickness of 50 µm to 300 µm. The sapphire substrate is a single crystal Al 2 O 3 The main component of the substrate is polycrystalline Al. 2 O 3 The main component of the spinel substrate is single crystal or polycrystalline MgAl 2 O 4 The main component of the quartz substrate is amorphous SiO 2 The main component of the quartz substrate is single crystal SiO 2 The main component of the substrate is

[0025] The piezoelectric layer 12 is, for example, a single crystal lithium tantalate layer or a single crystal lithium niobate layer, and has a thickness of 0.5 μm to 30 μm. The thickness of the piezoelectric layer 12 is, for example, smaller than the wavelength of the main mode acoustic wave excited by the acoustic wave element 50. The linear expansion coefficient of the support substrate 10 is smaller than the linear expansion coefficient of the piezoelectric layer 12. This allows the frequency temperature coefficient of the acoustic wave device 100 to be reduced. An insulating layer such as silicon oxide or aluminum nitride may be provided between the piezoelectric layer 12 and the support substrate 10. In this manner, the piezoelectric layer 12 is directly or indirectly bonded to the support substrate 10.

[0026] One or more acoustic wave elements 50 are provided on the upper surface of the piezoelectric layer 12. The acoustic wave elements 50 form series resonators S1 to S6 and parallel resonators P1 to P5.

[0027] FIG. 4 is a plan view of an acoustic wave element 50 in the first embodiment. As shown in FIG. 4, the acoustic wave element 50 is a surface acoustic wave resonator. An IDT 51 and a reflector 52 are provided on the upper surface of the piezoelectric layer 12. The IDT 51 has a pair of opposing comb electrodes 53. The comb electrodes 53 have a plurality of electrode fingers 54 and a bus bar 55 to which the plurality of electrode fingers 54 are connected. The IDT 51 excites a surface acoustic wave (main mode acoustic wave) in the piezoelectric layer 12. The pitch of the electrode fingers 54 of one of the pair of comb electrodes 53 is approximately the wavelength λ of the acoustic wave. That is, the wavelength λ of the acoustic wave is approximately equal to twice the pitch D of the plurality of electrode fingers 54. The IDT 51 and the reflector 52 are formed of a metal film such as aluminum, copper, or molybdenum. A protective film or a temperature compensation film covering the IDT 51 and the reflector 52 may be provided on the upper surface of the piezoelectric layer 12. The comb electrodes 53 may have dummy electrode fingers.

[0028] As shown in FIG. 2, FIG. 3(a), and FIG. 3(b), an input terminal 14a, an output terminal 14b, and a ground terminal 14c are provided on the lower surface of the support substrate 10. The input terminal 14a is a terminal to which a signal is input. The output terminal 14b is a terminal to which a signal is output. The ground terminal 14c is a terminal connected to the ground. The input terminal 14a corresponds to the input terminal Tin in FIG. 1, and the output terminal 14b corresponds to the output terminal Tout in FIG. 1. A plurality of via wirings 16a to 16c penetrating the support substrate 10 are provided. The series resonators S1 to S6 are connected in series between the input terminal 14a and the output terminal 14b through the via wiring 16a and the wiring 20. The parallel resonators P1 to P5 are connected in parallel between the input terminal 14a and the output terminal 14b by having one end connected to the wiring 20 connecting the series resonators S1 to S6 and the other end connected to the ground terminal 14c through the via wiring 16a.

[0029] The input terminal 14a, the output terminal 14b, the ground terminal 14c, the via wirings 16a to 16c, and the wiring 20 are metal layers including, for example, a titanium layer, a copper layer, an aluminum layer, a platinum layer, a nickel layer, and / or a gold layer, etc. The input terminal 14a, the output terminal 14b, the ground terminal 14c, the via wirings 16a to 16c, and the wiring 20 may be a single metal layer or a laminated metal layer in which multiple layers are laminated.

[0030] The piezoelectric layer 12 is not provided in the peripheral region of the support substrate 10. In a plan view, a frame 18 is provided on the support substrate 10 so as to surround the piezoelectric layer 12, the acoustic wave element 50, and the wiring 20. The frame 18 is provided on the support substrate 10 along the edge of the support substrate 10 away from the piezoelectric layer 12. For example, the support substrate 10 has a substantially rectangular shape in a plan view, and the frame 18 has a substantially rectangular annular (ring-shaped) shape in a plan view. The frame 18 is a metal layer containing, for example, copper, kovar, gold, aluminum, and / or tungsten. The frame 18 may be a silicon layer, a sapphire layer, or a resin layer. The frame 18 may be a single layer, or may be a laminate of multiple layers. The height of the frame 18 is, for example, about 15 μm to 30 μm, and the width is, for example, about 10 μm to 40 μm.

[0031] The lid 22 is provided on the frame 18 such that a gap 24 is formed between the frame 18 and the support substrate 10. The frame 18 and the lid 22 are joined by a bonding layer 26 such as solder. The acoustic wave element 50 is sealed in the gap 24 by the frame 18 and the lid 22. The lid 22 is a generally flat plate having a generally rectangular shape in a plan view. The lid 22 is made of a metal such as kovar, copper, gold, aluminum, and / or tungsten. The lid 22 may be made of silicon or sapphire. The lid 22 may be a single layer or may be a laminate of multiple layers. The thickness of the lid 22 is, for example, about 20 μm to 50 μm.

[0032] The frame body 18 is electrically connected to the ground terminal 14c through the via wiring 16b. As a result, a ground potential is supplied to the frame body 18 and the lid 22, so that the frame body 18 and the lid 22 exhibit a shielding effect. Note that the frame body 18 and the lid 22 are not electrically connected to the acoustic wave element 50 on the support substrate 10.

[0033] On the support substrate 10, line patterns 30a and 30b are provided, which are located between the end of the support substrate 10 and the acoustic wave element 50 and the wiring 20 in a plan view and extend along the frame body 18. In the first embodiment, the line patterns 30a and 30b extend along the frame body 18 so as to overlap the frame body 18 in a plan view. For example, the line patterns 30a and 30b entirely overlap the frame body 18 in the width direction. The line patterns 30a and 30b are embedded in a recess 44 provided on the upper surface of the support substrate 10. An insulating film 32 is provided between the line patterns 30a and 30b and the frame body 18 to electrically insulate the line patterns 30a and 30b from the frame body 18. The insulating film 32 is also embedded in a recess 44 provided on the upper surface of the support substrate 10. The upper surface of the insulating film 32 and the upper surface of the support substrate 10 are, for example, flush with each other.

[0034] One end of the line pattern 30a is electrically connected to the input terminal 14a through the via wiring 16c, and the other end is electrically connected to the ground terminal 14c through the via wiring 16c. As a result, the line pattern 30a forms an inductor L1 connected between the node between the input terminal Tin and the series resonator S1 in FIG. 1 and the ground. One end of the line pattern 30b is electrically connected to the output terminal 14b through the via wiring 16c, and the other end is electrically connected to the ground terminal 14c through the via wiring 16c. As a result, the line pattern 30b forms an inductor L2 connected between the node between the output terminal Tout and the series resonator S6 in FIG. 1 and the ground. The via wiring 16c to which the line patterns 30a and 30b are connected is provided so as to overlap the frame 18 in a plan view.

[0035] The line patterns 30a, 30b are formed of a metal layer including a titanium layer, a copper layer, an aluminum layer, a platinum layer, a nickel layer, and / or a gold layer. The line patterns 30a, 30b have a width of, for example, about 1.0 μm to 20 μm, and a thickness of, for example, about 0.2 μm to 5.0 μm. The insulating film 32 is formed of a resist, silicon oxide, or the like. The insulating film 32 has a width of, for example, about 1.0 μm to 25 μm, and a thickness of, for example, about 0.1 μm to 2.0 μm. For example, the width of the insulating film 32 is equal to or greater than the width of the line patterns 30a, 30b, and the thickness of the insulating film 32 is smaller than the thickness of the line patterns 30a, 30b.

[0036] [Manufacturing method] 5(a) to 6(c) are cross-sectional views showing a method for manufacturing the acoustic wave device 100 according to the first embodiment. As shown in FIG. 5(a), the upper surface of the support substrate 10 is irradiated with, for example, a laser beam to form a via hole, and a metal layer such as copper is formed in the via hole by, for example, electrolytic plating. Then, the upper surface of the metal layer is planarized by, for example, CMP (Chemical Mechanical Polishing) so that the upper surface of the support substrate 10 is exposed. As a result, via wirings 16a to 16c (only the via wirings 16a and 16c are shown in FIGS. 5(a) to 6(c)) are formed in the support substrate 10. Next, the piezoelectric substrate is bonded to the upper surface of the support substrate 10 at room temperature by, for example, a surface activation method. The support substrate 10 and the piezoelectric substrate may be directly bonded via an amorphous layer of several nm, or may be indirectly bonded via an insulating layer. Then, the upper surface of the piezoelectric substrate is polished by, for example, CMP. As a result, a piezoelectric layer 12 is formed that is directly or indirectly bonded to the upper surface of the support substrate 10.

[0037] 5(b), an acoustic wave element 50 is formed on the upper surface of the piezoelectric layer 12. Next, a portion of the piezoelectric layer 12 is removed, for example, by etching. This removes the piezoelectric layer 12 from the peripheral region of the support substrate 10, exposing the via wirings 16a to 16c. Next, a metal layer 40 is formed on the upper surfaces of the via wirings 16a and 16b other than the via wiring 16c to which the line patterns 30a and 30b are connected. The metal layer 40 is, for example, a titanium layer when the via wirings 16a to 16c are copper layers.

[0038] 5(c), the metal layer 40 is used as a mask to remove the upper portion of the via wiring 16c, for example, by etching. Next, a mask layer (not shown) is used as a mask to remove the upper portion of the support substrate 10 in the region where the line patterns 30a and 30b are to be formed, for example, by etching. As a result, a recess 44 is formed in the upper surface of the support substrate 10. The depth of the recess 44 is, for example, about 0.3 μm to 7.0 μm.

[0039] As shown in Fig. 5(d), metal layer 42 extending from acoustic wave element 50 onto metal layer 40 is formed by, for example, a lift-off method. Metal layer 42 is, for example, a laminated metal layer of a titanium layer and a gold layer. Metal layer 40 and metal layer 42 form wiring 20. Simultaneously with the formation of metal layer 42, line patterns 30a and 30b (only line pattern 30b is shown in Figs. 5(d) to 6(c)) are formed in recess 44.

[0040] 6(a), an insulating film 32 is formed on the line patterns 30a and 30b by using, for example, a lift-off method so as to fill the recesses 44. The insulating film 32 may be, for example, a resin film.

[0041] As shown in FIG. 6(b), a frame 18 and a bonding layer 26 are formed on the support substrate 10 by, for example, electrolytic plating. For example, the frame 18 includes a seed layer of a titanium layer and a copper layer, and a copper layer and a nickel layer provided in that order on the seed layer. For example, the bonding layer 26 is a gold-tin solder layer. Next, the lid 22 is bonded onto the frame 18 using the bonding layer 26. For example, a gold layer is provided on the surface of the lid 22, and the gold layer reacts with the bonding layer 26 to bond the lid 22 onto the frame 18. The acoustic wave element 50 is sealed in the gap 24 by the lid 22 and the frame 18.

[0042] As shown in Fig. 6(c), the lower surface of the support substrate 10 is polished by, for example, CMP. As a result, the via wirings 16a to 16c are exposed on the lower surface of the support substrate 10. Next, the input terminal 14a, the output terminal 14b, and the ground terminal 14c (the input terminal 14a is not shown in Fig. 6(c)) connected to the via wirings 16a to 16c are formed on the lower surface of the support substrate 10. In this manner, the acoustic wave device 100 in accordance with the first embodiment is manufactured.

[0043] [Comparative Example] 7 is a plan view of an acoustic wave device 1000 according to a comparative example mounted on a wiring board 80. As shown in FIG. 7, the acoustic wave device 1000 of the comparative example does not have line patterns 30a and 30b for forming inductors L1 and L2. Therefore, in order to form the inductors L1 and L2, a chip inductor 84 is provided on the wiring board 80, straddling a signal pad 82a and a ground pad 82b. If the chip inductor 84 is provided on the wiring board 80 in this way, the wiring board 80 becomes larger, and the module device becomes larger.

[0044] Fig. 8 is a plan view of the acoustic wave device 100 in accordance with the first embodiment mounted on a wiring board 80. As shown in Fig. 8, the inductors L1 and L2 are formed by the line patterns 30a and 30b provided on the support substrate 10, so there is no need to provide a chip inductor 84 on the wiring board 80. This allows the wiring board 80 to be made smaller, and prevents the module device from becoming larger.

[0045] According to the first embodiment, as shown in FIG. 2, the line patterns 30a and 30b are provided on the upper surface of the support substrate 10 in a plan view, positioned between the end of the support substrate 10 and the acoustic wave element 50 and the wiring 20 and extending along the frame 18. One end of the line pattern 30a is connected to the input terminal 14a (first terminal), and the other end is connected to the ground terminal 14c (second terminal). Thus, an inductor L1 is formed that is electrically connected to the acoustic wave element 50, the input terminal 14a, and the ground terminal 14c by the line pattern 30a. Similarly, one end of the line pattern 30b is connected to the output terminal 14b (first terminal), and the other end is connected to the ground terminal 14c (second terminal). Thus, an inductor L2 is formed that is electrically connected to the acoustic wave element 50, the output terminal 14b, and the ground terminal 14c by the line pattern 30b. 8, even when inductors L1 and L2 are provided to adjust the characteristics of the acoustic wave device 100, the wiring board 80 on which the acoustic wave device 100 is mounted can be prevented from becoming large, and the module device can be prevented from becoming large. Furthermore, overlapping between the line patterns 30a and 30b and the acoustic wave element 50 in the thickness direction of the support substrate 10 (i.e., overlapping in a plan view) is prevented, thereby reducing electrical coupling between the line patterns 30a and 30b and the acoustic wave element 50. As a result, deterioration of the characteristics of the acoustic wave device 100 can be prevented.

[0046] In the first embodiment, as shown in FIG. 2, the line patterns 30a and 30b are provided along the frame body 18 while overlapping the frame body 18 in a plan view. This makes it possible to prevent the acoustic wave device 100 from becoming large even when the line patterns 30a and 30b are provided on the upper surface of the support substrate 10. The line patterns 30a and 30b may have a part of their width overlapping the frame body 18 and extending along the frame body 18 in a plan view, but from the viewpoint of preventing the acoustic wave device 100 from becoming large, it is preferable that more than half of the width overlaps the frame body 18 and extends along the frame body 18 in a plan view, and more preferable that more than 2 / 3 of the width overlaps the frame body 18 and extends along the frame body 18. It is more preferable that more than 3 / 4 of the width overlaps the frame body 18 and extends along the frame body 18, and it is most preferable that the entire width overlaps the frame body 18 and extends along the frame body 18.

[0047] 3(a) and 3(b), in the first embodiment, the line patterns 30a and 30b are embedded in a recess 44 formed in the upper surface of the support substrate 10. This reduces the unevenness at the portion of the upper surface of the support substrate 10 where the frame 18 is provided, and suppresses a decrease in airtightness when the acoustic wave element 50 is sealed in the gap 24 by the frame 18 and the lid 22.

[0048] In the first embodiment, as shown in Figs. 3(a) and 3(b), an insulating film 32 is provided between the metal frame 18 and the line patterns 30a and 30b to electrically insulate the frame 18 from the line patterns 30a and 30b. This makes it possible to prevent the line patterns 30a and 30b from being electrically connected to the frame 18 and the lid 22 even when metal is used for the frame 18 and the lid 22 in consideration of airtightness when sealing the acoustic wave element 50 in the cavity 24 and / or a shielding effect for protecting the acoustic wave element 50. In order to seal the acoustic wave element 50 in the cavity 24 while maintaining good airtightness, it is preferable that the upper surface of the insulating film 32 and the upper surface of the support substrate 10 are substantially flush with each other. When the frame 18 is made of an insulating material such as sapphire or resin and the insulating film 32 is not provided, it is preferable that the upper surfaces of the line patterns 30a and 30b and the upper surface of the support substrate 10 are substantially flush with each other. The term "approximately flush" means that a step of the order of manufacturing error is permitted.

[0049] In the first embodiment, as shown in Fig. 2 and Fig. 3(b), a via wiring 16c (first via wiring) that connects one end of the line pattern 30a to the input terminal 14a and overlaps the frame body 18 in a planar view is provided on the support substrate 10. A via wiring 16c (second via wiring) that connects the other end of the line pattern 30a to the ground terminal 14c and overlaps the frame body 18 in a planar view is provided on the support substrate 10. Similarly, as shown in Fig. 2 and Fig. 3(a), a via wiring 16c (first via wiring) that connects one end of the line pattern 30b to the output terminal 14b and overlaps the frame body 18 in a planar view is provided on the support substrate 10. A via wiring 16c (second via wiring) that connects the other end of the line pattern 30b to the ground terminal 14c and overlaps the frame body 18 in a planar view is provided on the support substrate 10. In this way, by overlapping the via wiring 16c with the frame body 18, when the frame body 18 has a shielding effect, the influence of the via wiring 16c on the outside can be suppressed. In addition, since the via wiring 16c also contributes to the inductance of the inductors L1 and L2, it is possible to obtain inductors L1 and L2 with large inductance. From the viewpoint of suppressing the influence on the outside, it is preferable that more than half of the area of ​​the via wiring 16c overlaps with the frame body 18 in a plan view, more preferably that more than 2 / 3 of the area overlaps with the frame body 18, even more preferably that more than 3 / 4 of the area overlaps with the frame body 18, and most preferably that the entire area overlaps with the frame body 18.

[0050] 2, in the first embodiment, a via wiring 16b (third via wiring) that connects the frame body 18 and the ground terminal 14c is provided in the support substrate 10. This allows a ground potential to be supplied to the frame body 18 and the lid 22, and a shielding effect can be imparted to the frame body 18 and the lid 22. EXAMPLES

[0051] FIG. 9 is a cross-sectional view of an acoustic wave device 200 according to a second embodiment. FIG. 9 is a cross-sectional view of a portion corresponding to the BB interval in FIG. 2. As shown in FIG. 9, in the acoustic wave device 200, the line pattern 30a is a meander line pattern, and extends in a meandering manner in the thickness direction of the support substrate 10 with an insulating film 36 sandwiched therebetween. For example, the line pattern 30a extends in a meandering manner to form a lower layer, a middle layer, and an upper layer, and the insulating film 36 is provided between the lower layer and the middle layer and between the middle layer and the upper layer. Note that, although FIG. 9 shows an example in which the line pattern 30a is a meander line pattern with a three-layer structure, the line pattern 30a may be a meander line pattern with a layer structure of two layers or four or more layers. Also, in FIG. 9, only the line pattern 30a of the line patterns 30a and 30b is shown, but the line pattern 30b may also be the same meander line pattern as the line pattern 30a. The other configurations are the same as those in the first embodiment, and therefore will not be described.

[0052] According to the second embodiment, the line pattern 30a is a meandering line pattern that is provided meandering in the thickness direction of the support substrate 10. This makes it possible to increase the inductance of the inductor L1 formed by the line pattern 30a.

[0053] [Variations] FIG. 10 is a plan view of an acoustic wave device 210 according to a first modification of the second embodiment. As shown in FIG. 10, in the acoustic wave device 210, the line patterns 30a and 30b are meandering line patterns and extend in a meandering manner in the surface direction of the upper surface of the support substrate 10. Note that, although FIG. 10 shows an example in which the line patterns 30a and 30b are meandering line patterns having three substantially parallel lines, the line patterns may be meandering line patterns having two or four or more substantially parallel lines. Also, only one of the line patterns 30a and 30b may be a meandering line pattern. The other configurations are the same as those of the first embodiment, and therefore description thereof will be omitted.

[0054] According to the first modification of the second embodiment, the line patterns 30a and 30b are meandering line patterns provided in a meandering manner in the planar direction of the upper surface of the support substrate 10. This makes it possible to increase the inductance of the inductors L1 and L2 formed by the line patterns 30a and 30b.

[0055] 11(a) and 11(b) are perspective views of the vicinity of the line pattern 30a of the acoustic wave device 220 according to the second modification of the second embodiment. In FIG. 11(a), the line pattern 30a is illustrated with hatching, as seen through the insulating films 32 and 36, and in FIG. 11(b), the insulating films 32 and 36 are illustrated with hatching. As shown in FIG. 11(a) and FIG. 11(b), in the acoustic wave device 220, the line pattern 30a is a meandering line pattern, and extends while meandering in both the thickness direction and the surface direction of the support substrate 10. That is, the line pattern 30a extends while meandering in the surface direction of the support substrate 10 in each of the lower layer, middle layer, and upper layer, and extends while meandering in the thickness direction of the support substrate 10 by connecting each layer with a via wiring 38. An insulating film 36 is provided between the lower layer and the middle layer and between the middle layer and the upper layer. As described above, the number of layers of the meander line pattern and the number of approximately parallel lines in the planar direction can be changed as appropriate. In addition, although only the line pattern 30a of the line patterns 30a and 30b is shown in Fig. 11(a) and Fig. 11(b), the line pattern 30b may also be a meander line pattern similar to the line pattern 30a. The other configurations are the same as those in the first embodiment, and therefore will not be described.

[0056] According to the second modification of the second embodiment, the line pattern 30a is a meandering line pattern that is provided meandering in the thickness direction and the surface direction of the support substrate 10. This makes it possible to increase the inductance of the inductor L1 formed by the line pattern 30a.

[0057] The line patterns 30a and 30b are not limited to the straight line pattern as in the first embodiment or the meandering line pattern as in the second embodiment and its modified example 2, but may be other patterns such as a spiral line pattern. EXAMPLES

[0058] 12(a) and 12(b) are cross-sectional views of an acoustic wave device 300 according to a third embodiment. FIG. 12(a) is a cross-sectional view of a portion corresponding to the AA section in FIG. 2, and FIG. 12(b) is a cross-sectional view of a portion corresponding to the BB section in FIG. 2. As shown in FIG. 12(a) and FIG. 12(b), in the acoustic wave device 300, the line patterns 30a and 30b and the insulating film 32 are provided on a flat surface on the upper surface of the support substrate 10. That is, the recess 44 is not formed on the upper surface of the support substrate 10. The insulating film 32 is provided so as to cover the upper and side surfaces of the line patterns 30a and 30b. For example, the width of the line patterns 30a and 30b is smaller than the width of the frame body 18, and the width of the insulating film 32 is approximately the same as the width of the frame body 18. Approximately the same size means that the width of the frame body 18 is 95% or more and 105% or less of the width of the insulating film 32. The other configurations are the same as those of the first embodiment, and therefore will not be described.

[0059] In the first embodiment to the second modification of the second embodiment, the line patterns 30a, 30b and the insulating film 32 are provided in a recess 44 formed in the support substrate 10. However, this is not limited to the above, and the line patterns 30a, 30b and the insulating film 32 may be provided on the flat surface of the upper surface of the support substrate 10, as in the third embodiment. In this case, the step of forming the recess 44 is not required, and therefore the number of manufacturing steps can be reduced. EXAMPLES

[0060] FIG. 13 is a plan view of an acoustic wave device 400 according to a fourth embodiment. FIG. 14(a) is a cross-sectional view taken along line AA in FIG. 13, and FIG. 14(b) is a cross-sectional view taken along line BB in FIG. 13. As shown in FIG. 13, FIG. 14(a), and FIG. 14(b), in the acoustic wave device 400, the line patterns 30a and 30b are connected to the wiring 20 on the upper surface of the support substrate 10. One end of the line pattern 30a is connected to the input terminal 14a via the wiring 20 and the via wiring 16a, and the other end is connected to the ground terminal 14c via the wiring 20 and the via wiring 16a. One end of the line pattern 30b is connected to the output terminal 14b via the wiring 20 and the via wiring 16a, and the other end is connected to the ground terminal 14c via the wiring 20 and the via wiring 16a. The other configurations are the same as those in the first embodiment, and therefore will not be described.

[0061] In the first to third embodiments, the line patterns 30a and 30b are connected to the input terminal 14a or the output terminal 14b through the via wiring 16c provided so as to overlap the frame body 18 in a plan view, and the other end is connected to the ground terminal 14c through the via wiring 16c provided so as to overlap the frame body 18 in a plan view, but the present invention is not limited to this case. As in the fourth embodiment, one end of the line pattern 30a may be connected to the wiring 20 (first wiring) on ​​the upper surface of the support substrate 10, thereby being connected to the input terminal 14a through the wiring 20 and the via wiring 16a (first via wiring) overlapping the wiring 20 in a plan view. The other end of the line pattern 30a may be connected to the wiring 20 (second wiring) on ​​the upper surface of the support substrate 10, thereby being connected to the ground terminal 14c through the wiring 20 and the via wiring 16a (second via wiring) overlapping the wiring 20 in a plan view. The same applies to the line pattern 30b. In this case, the adjustment range of the length of the line patterns 30a, 30b becomes large, and therefore the adjustment range of the inductance of the inductors L1, L2 can be made large. EXAMPLES

[0062] FIG. 15 is a plan view of an acoustic wave device 500 according to a fifth embodiment. FIG. 16(a) is a cross-sectional view taken along line AA in FIG. 15, and FIG. 16(b) is a cross-sectional view taken along line BB in FIG. 15. In FIG. 15, the frame 18 is hatched in addition to the wiring 20 and the line patterns 30a and 30b. As shown in FIG. 15, FIG. 16(a), and FIG. 16(b), in the acoustic wave device 500, the line patterns 30a and 30b are located between the frame 18 and the acoustic wave element 50 and the wiring 20 in a plan view and are provided along the frame 18. That is, the line patterns 30a and 30b are provided along the frame 18 without overlapping with the frame 18. The line patterns 30a and 30b are provided on the support substrate 10 without the piezoelectric layer 12 therebetween. The other configurations are the same as those in the first embodiment, and therefore will not be described. EXAMPLES

[0063] FIG. 17 is a plan view of an acoustic wave device 600 according to a sixth embodiment. FIG. 18(a) is a cross-sectional view taken along line AA in FIG. 17, and FIG. 18(b) is a cross-sectional view taken along line BB in FIG. 17. In FIG. 17, the frame 18 is hatched in addition to the wiring 20 and the line patterns 30a and 30b. As shown in FIG. 17, FIG. 18(a), and FIG. 18(b), in the acoustic wave device 600, the line patterns 30a and 30b are located between the frame 18 and the end of the support substrate 10 in a plan view and are provided along the frame 18. That is, the line patterns 30a and 30b are provided along the frame 18 without overlapping with the frame 18. The line patterns 30a and 30b are provided on the support substrate 10 without the piezoelectric layer 12 therebetween. The other configurations are the same as those in the first embodiment, and therefore will not be described. In the sixth embodiment, the distance between the line patterns 30a and 30b and the acoustic wave element 50 is increased, which reduces electrical coupling between the line patterns 30a and 30b and the acoustic wave element 50. As a result, deterioration of the characteristics of the acoustic wave device 600 can be suppressed.

[0064] As in the fifth embodiment, the line patterns 30a and 30b may be located between the frame body 18 and the acoustic wave element 50 and the wiring 20 in a plan view and provided along the frame body 18. As in the sixth embodiment, the line patterns 30a and 30b may be located between the frame body 18 and the end of the supporting substrate 10 and provided along the frame body 18 in a plan view. In this manner, the line patterns 30a and 30b may not overlap the frame body 18 as long as they are located between the end of the supporting substrate 10 and the acoustic wave element 50 and the wiring 20 in a plan view and provided along the frame body 18.

[0065] In Examples 5 and 6, from the standpoint of miniaturizing the acoustic wave device, it is preferable that the distance between the line patterns 30a, 30b and frame body 18 at the locations along the frame body 18 is smaller than 1 / 2 the width of the frame body 18, more preferably smaller than 1 / 4 the width of the frame body 18, and even more preferably smaller than 1 / 10 the width of the frame body 18. EXAMPLES

[0066] FIG. 19 is a cross-sectional view of an acoustic wave device 700 according to a seventh embodiment. FIG. 19 is a cross-sectional view of a portion corresponding to the AA portion in FIG. 2. As shown in FIG. 19, in the acoustic wave device 700, an acoustic wave element 50a is provided on a support substrate 10 instead of the acoustic wave element 50. The acoustic wave element 50a is a piezoelectric thin film resonator. The acoustic wave element 50a includes a piezoelectric layer 62 provided on the support substrate 10, and a lower electrode 60 and an upper electrode 64 sandwiching the piezoelectric layer 62. A gap 66 is formed between the lower electrode 60 and the support substrate 10. A region where the lower electrode 60 and the upper electrode 64 face each other with at least a part of the piezoelectric layer 62 sandwiched therebetween is a resonance region 68. In the resonance region 68, the lower electrode 60 and the upper electrode 64 excite an acoustic wave in a thickness longitudinal vibration mode in the piezoelectric layer 62. An insertion film may be inserted in the outer peripheral region of the resonance region 68 of the piezoelectric layer 62 to increase the Q value or for temperature compensation.

[0067] The lower electrode 60 and the upper electrode 64 are, for example, metal films including a ruthenium film. The piezoelectric layer 62 is, for example, an aluminum nitride layer or a zinc oxide layer. An acoustic reflection film that reflects elastic waves may be provided instead of the gap 66. The acoustic wave element 50a is manufactured by a generally known method.

[0068] As in the first to sixth embodiments, the acoustic wave element provided on supporting substrate 10 may be acoustic wave element 50 including comb-shaped electrode 53 provided on piezoelectric layer 12 which is a single crystal lithium tantalate layer or a single crystal lithium niobate layer. As in the seventh embodiment, the acoustic wave element may be acoustic wave element 50a which is a piezoelectric thin film resonator in which lower electrode 60 and upper electrode 64 are provided with piezoelectric layer 62 sandwiched therebetween.

[0069] In Examples 1 to 7, in order to ensure inductance, the length of the line patterns 30a, 30b is preferably at least 1 / 2 the length of the side along which the line patterns 30a, 30b are arranged among the multiple sides of the support substrate 10, more preferably at least 3 / 4 the length, and even more preferably at least 7 / 8 the length. EXAMPLES

[0070] FIG. 20 is a cross-sectional view of an acoustic wave device 800 in accordance with the eighth embodiment. FIG. 20 is a cross-sectional view of a portion corresponding to the portion between BB in FIG. 2. As shown in FIG. 20, the acoustic wave device 800 includes a line pattern 31a that is connected to the input terminal 14a and not connected to the ground terminal 14c, and a line pattern 31b that is connected to the ground terminal 14c and not connected to the input terminal 14a. The line patterns 31a and 31b face each other in the thickness direction of the support substrate 10 with a dielectric film 39 sandwiched therebetween. Thus, a capacitor C is formed by the line patterns 31a and 31b. The other configurations are the same as those of the first embodiment, and therefore will not be described.

[0071] In the first to seventh embodiments, the passive elements are inductors L1 and L2 formed by the line patterns 30a and 30b, but the present invention is not limited to this. As in the eighth embodiment, the passive elements may be capacitors C in which the line patterns 31a and 31b face each other. The passive elements may be connected in series between the input terminal 14a and the series resonator S1 and / or between the output terminal 14b and the series resonator S6.

[0072] In the eighth embodiment, the line pattern 31a and the line pattern 31b face each other in the thickness direction of the support substrate 10, but they may face each other in the surface direction of the upper surface of the support substrate 10. In the eighth embodiment, in order to ensure capacitance, the length of the line pattern 31a and the line pattern 31b is preferably 1 / 2 or more of the length of the side along which the line patterns 31a and 31b are provided among the multiple sides of the support substrate 10, more preferably 3 / 4 or more, and even more preferably 7 / 8 or more.

[0073] In the first to seventh embodiments, the line patterns 30a, 30b, 31a, and 31b are provided along the short sides of the support substrate 10 in plan view. However, this is not limited to the above case, and the line patterns 30a, 30b, 31a, and 31b may be provided along the long sides or from the short sides to the long sides.

[0074] In the first to eighth embodiments, the piezoelectric layer 12 is provided on the support substrate 10, but the piezoelectric layer 12 may be a thick piezoelectric substrate without the support substrate 10.

[0075] In the first to eighth embodiments, a filter is formed on the support substrate 10 by a plurality of acoustic wave elements 50, but the present invention is not limited to this, and a multiplexer may be formed. FIG. 21 is a block diagram showing an example of a multiplexer. As shown in FIG. 21, a transmission filter 70 is connected between a common terminal Ant and a transmission terminal Tx. A reception filter 72 is connected between the common terminal Ant and a reception terminal Rx. The transmission filter 70 passes a signal in a transmission band among high-frequency signals input from the transmission terminal Tx to the common terminal Ant as a transmission signal, and suppresses signals of other frequencies. The reception filter 72 passes a signal in a reception band among high-frequency signals input from the common terminal Ant to the reception terminal Rx as a reception signal, and suppresses signals of other frequencies. Note that, although a duplexer is shown as an example of the multiplexer in FIG. 21, a triplexer, a quadplexer, or the like may be used.

[0076] Although the embodiment of the present invention has been described in detail above, the present invention is not limited to such specific embodiment, and various modifications and variations are possible within the scope of the gist of the present invention described in the claims. [Explanation of symbols]

[0077] 10 Support substrate 12 Piezoelectric layer 14a Input terminal 14b Output terminal 14c Ground terminal 16a, 16b, 16c Via wiring 18 Frame 20 Wiring 22 Lid 24 void 26 Bonding layer 30a, 30b, 31a, 31b track patterns 32 Insulating film 36 Insulating Film 38 Via wiring 39 Dielectric Film 40, 42 metal layer 44 Recess 50, 50a Elastic wave element 51 IDT 52 Reflector 53 Comb-shaped electrode 54 Electrode finger 55 Busbar 60 Lower electrode 62 Piezoelectric layer 64 Upper electrode 66 void 68 Resonance region 70 Transmission Filter 72 Receiving Filter 80 Wiring board 82a Signal Pad 82b Ground pad 84 Chip inductors 100, 200, 210, 220, 300, 400, 500, 600, 700, 800, 1000 Acoustic Wave Devices

Claims

1. A substrate, a piezoelectric layer provided on one surface of the substrate, an elastic wave element including an electrode provided on the piezoelectric layer, a wiring provided on the one surface of the substrate and electrically connected to the elastic wave element, a terminal provided on the other surface of the substrate, an element via wiring provided on the substrate and connecting the wiring and the terminal, a frame provided on the one surface of the substrate along an edge of the substrate and surrounding the piezoelectric layer, the elastic wave element, and the wiring in a plan view, a lid provided on the frame with a gap interposed between the lid and the substrate and sealing the elastic wave element in the gap, a passive element formed by one or a plurality of line patterns located between an edge of the substrate and the elastic wave element and the wiring on the one surface of the substrate in a plan view, overlapping the frame, and provided along the frame, and electrically connected to the elastic wave element and the terminal. An elastic wave device comprising:

2. The elastic wave device according to claim 1, wherein the one or a plurality of line patterns are embedded in a recess formed in the one surface of the substrate.

3. The elastic wave device according to claim 1 or 2, further comprising an insulating film that electrically insulates the frame and the one or a plurality of line patterns from each other between the metal frame and the one or a plurality of line patterns.

4. A plurality of the terminals are provided on the other surface of the substrate, the one or a plurality of line patterns is one line pattern having one end connected to a first terminal among the plurality of terminals and the other end connected to a second terminal among the plurality of terminals, The elastic wave device according to any one of claims 1 to 3, wherein the passive element is an inductor formed by the one line pattern.

5. a first via wiring provided on the substrate, connecting one end of the one line pattern and the first terminal, and overlapping the frame in a plan view, a second via wiring provided on the substrate, connecting the other end of the one line pattern and the second terminal, and overlapping the frame in a plan view. The elastic wave device according to claim 4.

6. The elastic wave device according to claim 4 or 5, further comprising a third via wiring provided on the substrate and connecting the frame and a ground terminal among the plurality of terminals.

7. A plurality of the wirings and a plurality of the element via wirings are provided on the substrate, The plurality of via wirings for elements connect the first wiring among the plurality of wirings and the first terminal, and include a first via wiring that overlaps the first wiring in a plan view, and a second via wiring that connects the second wiring among the plurality of wirings and the second terminal and overlaps the second wiring in a plan view. One end of the one line pattern is connected to the first wiring on the one surface of the substrate, and thus is connected to the first terminal via the first wiring and the first via wiring. The elastic wave device according to claim 4, wherein the other end of the one line pattern is connected to the second wiring on the one surface of the substrate, and thus is connected to the second terminal via the second wiring and the second via wiring.

8. The elastic wave device according to any one of claims 4 to 7, wherein the one line pattern is a meander line pattern provided to meander in at least one of the thickness direction of the substrate and the one surface direction of the substrate.

9. The one or more line patterns are two line patterns. The elastic wave device according to any one of claims 1 to 3, wherein the passive element is a capacitor in which the two line patterns face each other.

10. The elastic wave device according to any one of claims 1 to 9, wherein a filter is formed by a plurality of the elastic wave elements.

11. The elastic wave device according to claim 10, wherein a multiplexer is formed by the filter.

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