JP2014011487A - Acoustic wave device and manufacturing method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an acoustic wave device which is small, has a low height, and achieves good moisture resistance, and to provide a manufacturing method of the acoustic wave device.SOLUTION: An acoustic wave device of this invention includes: surface acoustic wave elements 12 provided on a substrate 10; first wiring 34 which is provided on the substrate 10 and is electrically connected with the surface acoustic wave elements 12; a frame 22 which is provided on the substrate 10 so as to enclose the surface acoustic wave elements 12, intersects with the first wiring 34, and is made of a metal electrically separated from the first wiring 34; and a lid 26 which is provided on the frame 22 so as to have a cavity 24 on the surface acoustic wave elements 12 and is made of a metal.

Description

  The present invention relates to an acoustic wave device and a manufacturing method thereof.

  An elastic wave device using an elastic wave is used for a filter of a wireless terminal such as a mobile phone terminal, for example. Examples of the acoustic wave element used in the acoustic wave device include a surface acoustic wave element in which an IDT (Interdigital Transducer) electrode is formed on a piezoelectric substrate and a piezoelectric thin film resonant element in which a piezoelectric film is sandwiched between upper and lower electrodes.

  In the acoustic wave device, in order to maintain the characteristics of the acoustic wave element, a structure in which a cavity is provided on a functional portion of the acoustic wave element (so-called hollow structure) is used. The functional part of the acoustic wave element is an electrode finger of the IDT electrode in the surface acoustic wave element, and an area where the upper and lower electrodes sandwiching the piezoelectric film overlap in the piezoelectric thin film resonant element.

  As a method of providing a cavity on a functional part of an acoustic wave element, for example, a method in which a substrate on which an acoustic wave element is formed is flip-chip bonded to a base substrate, or a resin sealing portion is formed on a substrate so as to cover the acoustic wave element There are known methods (see, for example, Patent Document 1 and Patent Document 2).

JP 2004-129193 A JP 2008-135998 A

  In a method in which a cavity is provided on a functional portion of an acoustic wave element by flip-chip bonding a substrate on which an acoustic wave element is formed to a base substrate, it is difficult to reduce the size and height. In the method of providing a cavity on the functional portion of the acoustic wave element by covering the acoustic wave element and forming the resin sealing portion, the acoustic wave element is sealed with resin, so that the moisture resistance is poor. Reliability will deteriorate.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an elastic wave device having a small size, a low profile and good moisture resistance, and a method for manufacturing the same.

  The present invention includes an acoustic wave element provided on a substrate, a wiring provided on the substrate and electrically connected to the acoustic wave element, and provided on the substrate so as to surround the acoustic wave element. A frame made of metal that intersects with the wiring and is electrically separated from the wiring, and a lid made of metal provided on the frame with a cavity on the acoustic wave element; It is an elastic wave device characterized by providing. According to the present invention, an elastic wave device having a small size, a low profile, and good moisture resistance can be obtained.

  In the above configuration, the projection electrode is provided on the substrate outside the frame body and electrically connected to the wiring, and the projection electrode has a lower portion made of the same metal as the frame body, The portion may be made of the same metal as the lid.

  In the above configuration, the height from the upper surface of the substrate to the upper surface of the lid may be the same as the height from the upper surface of the substrate to the upper surface of the protruding electrode.

  The said structure WHEREIN: It can be set as the structure by which the 1st insulator which covers the said wiring located in the outer side of the said frame is provided.

  The said structure WHEREIN: It can be set as the structure by which the brazing material is provided between the said frame and the said lid | cover.

  The said structure WHEREIN: It can be set as the structure by which the 2nd insulator is provided between the said wiring and the said frame.

  The present invention includes a step of forming an acoustic wave element and a wiring electrically connected to the acoustic wave element on a substrate, and surrounds the acoustic wave element on the substrate and intersects the wiring. And a step of forming a frame made of a metal electrically separated from the wiring, a step of bonding a metal plate on the frame, and an etching process on the metal plate, And forming a lid made of a metal having a cavity on the acoustic wave element on the body. According to the present invention, an elastic wave device having a small size, a low profile, and good moisture resistance can be obtained.

  In the above-described configuration, the method includes a step of forming a protruding electrode electrically connected to the wiring on the substrate outside the frame, and the frame and the lower portion of the protruding electrode are formed by electrolytic plating. The upper portion of the protruding electrode is formed by joining the metal plate on the frame and the lower portion of the protruding electrode, and then etching the metal plate. , And the lid can be formed at the same time.

  In the above configuration, a plurality of the acoustic wave elements are formed on the substrate, and simultaneously with the separation of the plurality of acoustic wave elements, the feeding wire for plating used in the electrolytic plating method is cut. The protruding electrode electrically connected to the separated acoustic wave element and the frame surrounding the separated acoustic wave element are electrically separated by be able to.

  The said structure WHEREIN: After forming the said frame, before performing the etching process with respect to the said metal plate, it can be set as the structure which has the process of pouring an insulator from the edge of the said board | substrate so that the said wiring may be covered.

  According to the present invention, an elastic wave device having a small size, a low profile, and good moisture resistance can be obtained.

FIG. 1A is a top view of the acoustic wave device according to the first embodiment, and FIG. 1B is a cross-sectional view taken along a line AA in FIG. FIG. 2 is a cross-sectional view of a portion where the wiring and the frame intersect. FIG. 3A is a perspective view of the acoustic wave device according to the first embodiment, and FIG. 3B is a perspective view when the second insulator is seen through. FIG. 4A to FIG. 4E are cross-sectional views (part 1) illustrating the method for manufacturing the acoustic wave device according to the first embodiment. FIG. 5A to FIG. 5D are cross-sectional views (part 2) illustrating the method for manufacturing the acoustic wave device according to the first embodiment. 6A to 6C are cross-sectional views (part 3) illustrating the method for manufacturing the acoustic wave device according to the first embodiment. 7A and 7B are top views (part 1) illustrating the method for manufacturing the acoustic wave device according to the first embodiment. FIG. 8A and FIG. 8B are top views (part 2) illustrating the method for manufacturing the acoustic wave device according to the first embodiment. FIG. 9 is a top view (No. 3) illustrating the method for manufacturing the acoustic wave device according to the first embodiment. FIG. 10 is a top view showing a cutting region formed on a wafer-like substrate.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1A is a top view of the acoustic wave device according to the first embodiment, and FIG. 1B is a cross-sectional view taken along a line AA in FIG. In FIG. 1A, the lid 26 and the insulator 38 are shown through. As shown in FIGS. 1A and 1B, two surface acoustic wave elements 12 are formed on a piezoelectric substrate 10 such as a lithium niobate substrate (LN substrate) or a lithium tantalate substrate (LT substrate). Is provided. One of the surface acoustic wave elements 12 has an IDT electrode IDT1 and reflective electrodes R1 located on both sides in the propagation direction of the elastic wave. The other has IDT electrodes IDT2 and IDT3, and reflective electrodes R2 located on both sides of the elastic wave in the propagation direction. The IDT electrode IDT1 and the IDT electrode IDT3 are connected by a wiring 14. Thereby, the two surface acoustic wave elements 12 are connected in series. The reflective electrode R1 and the reflective electrode R2 are connected by a wiring 16. The IDT electrodes IDT1 to IDT3 and the reflective electrodes R1 and R2 are formed of a metal such as aluminum (Al).

  When an unbalanced signal is input to the IDT electrode IDT1, the signal propagates to the IDT electrode IDT3 via the wiring 14 and is output from the IDT electrode IDT2 as a balanced signal. As described above, the elastic wave device according to the first embodiment is an unbalanced input-balanced output type multimode surface acoustic wave device.

  An annular wiring 18 is provided on the substrate 10 so as to surround the two surface acoustic wave elements 12. The annular wiring 18 is made of a metal such as Al. A frame body 22 is provided on the annular wiring 18 via a metal film 20. That is, the frame 22 is also provided so as to surround the two surface acoustic wave elements 12. The annular wiring 18 and the frame body 22 preferably completely surround the two surface acoustic wave elements 12. The metal film 20 is a laminated film in which gold (Au) is laminated on titanium (Ti), and the thickness thereof is 0.05 μm. The frame 22 is a metal film such as a laminated film in which gold (Au) is laminated on nickel (Ni).

  A lid 26 having a cavity 24 on the surface acoustic wave element 12 is provided on the frame 22. The lid | cover 26 is formed with metals, such as copper (Cu). The frame 22 and the lid 26 are joined by a brazing material made of tin (Sn). Therefore, the brazing material 28 is interposed between the frame 22 and the lid 26. The surface acoustic wave element 12 is sealed by a frame body 22 and a lid 26. In other words, the frame body 22 and the lid 26 are sealing portions that seal the surface acoustic wave element 12. Since the cavity 24 is formed on the surface acoustic wave element 12, the characteristics of the surface acoustic wave element 12 can be maintained.

  A protruding electrode 30 that is electrically connected to the surface acoustic wave element 12 via a first wiring 34 is provided on the substrate 10 outside the frame body 22 (on the end side of the substrate 10). The first wiring 34 is formed of a metal such as Al, and the thickness thereof is the same as that of the annular wiring 18. A portion where the first wiring 34 and the frame body 22 intersect has a three-dimensional wiring structure. FIG. 2 is a cross-sectional view of a portion where the first wiring 34 and the frame body 22 intersect. In FIG. 2, the metal film 20 is not shown for the sake of clarity. As shown in FIG. 2, an insulator 36 is provided between the first wiring 34 and the frame body 22. The insulator 36 is made of a resin such as a photosensitive resin (for example, polyimide), and the thickness thereof can be 1 μm. By this insulator 36, the first wiring 34 and the frame body 22 are electrically separated. In order to electrically isolate the first wiring 34 and the frame body 22, the insulator 36 is preferably formed so as to completely cover a region where the first wiring 34 and the frame body 22 intersect. More preferably, the region is larger than the intersecting region.

  The protruding electrode 30 is provided on the substrate 10 via the second wiring 40 and the metal film 20. The second wiring 40 is made of a metal such as Al, and the thickness thereof is the same as that of the annular wiring 18 and the first wiring 34. The lower portion 32 a of the protruding electrode 30 is formed of the same metal as the frame body 22. The upper portion 32 b of the protruding electrode 30 is made of the same metal as the lid 26. The lower portion 32a and the upper portion 32b of the protruding electrode 30 are joined by a brazing material 28 made of Sn.

  The thickness of the frame 22 and the thickness of the lower portion 32a of the protruding electrode 30 are the same, for example, 20 μm. The thickness of the lid 26 and the thickness of the upper portion 32b of the protruding electrode 30 are the same, for example, 35 μm. Therefore, the height from the upper surface of the substrate 10 to the upper surface of the lid 26 is the same as the height from the upper surface of the substrate 10 to the upper surface of the protruding electrode 30. Note that an insulator 36 is provided at a portion where the first wiring 34 and the frame body 22 intersect, but the thickness of the insulator 36 is the total thickness of the frame body 22 and the lid 26 or the protruding electrode. Very small compared to 30 thickness. For this reason, the thickness of the insulator 36 can be ignored.

  FIG. 3A is a perspective view of the acoustic wave device according to the first embodiment, and FIG. 3B is a perspective view when the insulator 38 is seen through. As shown in FIGS. 1A to 3B, an insulator 38 is provided on the substrate 10 outside the frame body 22 (on the end side of the substrate 10) so as to cover the first wiring 34 and the like. . The insulator 38 is made of a resin such as an epoxy resin, and has a thickness of about 10 μm, for example. The height from the upper surface of the substrate 10 to the upper surface of the insulator 38 is lower than the height from the upper surface of the substrate 10 to the upper surfaces of the lid 26 and the protruding electrode 30. Therefore, the lid 26 and the protruding electrode 30 protrude from the upper surface of the insulator 38.

  The second wiring 40 provided under the protruding electrode 30 extends to the end of the substrate 10. Although described in detail later, the second wiring 40 functions as a plating power supply line when the lower portion 32a of the protruding electrode 30 is formed by an electrolytic plating method. A third wiring 42 is provided on the substrate 10 between the end of the substrate 10 and the frame body 22. The third wiring 42 is formed of a metal such as Al, and the thickness thereof is the same as that of the annular electrode 18, the first wiring 34, and the second wiring 40. As will be described in detail later, the third wiring 42 functions as a feeding wire for plating when the frame 22 is formed by an electrolytic plating method.

  Next, a method for manufacturing the acoustic wave device according to the first embodiment will be described. FIG. 4A to FIG. 6C are cross-sectional views illustrating the method for manufacturing the acoustic wave device according to the first embodiment. FIG. 7A to FIG. 9 are top views illustrating the method for manufacturing the acoustic wave device according to the first embodiment. 4 (a) to 5 (d) are cross-sectional views of a portion corresponding to AA in FIG. 1, and FIGS. 6 (a) to 6 (c) are cross-sectional views of FIG. It is sectional drawing of the location corresponded between B. In addition, the acoustic wave device is manufactured using a wafer-state piezoelectric substrate, and there are regions on the wafer that should be a plurality of acoustic wave devices. In FIGS. One acoustic wave device will be described with reference to FIGS. 7A to 9.

  As shown in FIGS. 4A, 6A, and 7A, on a substrate 10 having a piezoelectric property such as an LN substrate or an LT substrate, an evaporation method and a lift-off method are used to form Al. Forming a metal layer. As a result, a plurality of surface acoustic wave elements 12 having a pair of two surface acoustic wave elements 12 having an IDT electrode and a reflective electrode and connected in series are formed. An annular wiring 18 surrounding the two surface acoustic wave elements 12 connected in series is formed. A fourth wiring 44 is formed in a cutting region when the acoustic wave device is separated. A second wiring 40 extending from the region where the protruding electrode 30 is to be formed to the fourth wiring 44 is formed. A first wiring 34 for connecting the surface acoustic wave element 12 and the second wiring 40 is formed. A third wiring 42 that connects the annular wiring 18 and the fourth wiring 44 is formed.

  Next, a protective film 46 made of an oxide film such as silicon oxide or a nitride film such as silicon nitride is deposited on the substrate 10 by sputtering. Thereafter, the protective film 46 in a region other than the region where the surface acoustic wave element 12 is formed and the region where the annular wiring 18 and the first wiring 34 intersect is removed by an etching method. For the purpose of clarifying the drawing, the protective film 46 is not shown in the drawings other than FIGS. 4A to 4C and FIGS. 6A to 6C.

  As shown in FIG. 4B, FIG. 6B, and FIG. 7B, an insulator 36 made of a photosensitive resin such as polyimide is applied on the substrate 10 and then exposed to and developed to form a circular wiring. The insulator 36 is left only in the portion where the 18 and the first wiring 34 intersect. Thereafter, the insulator 36 is subjected to heat treatment and cured.

  4C, FIG. 6C, and FIG. 8A, openings are formed on the substrate 10 on the annular wiring 18 and on the second wiring 40 in the region where the protruding electrodes 30 are to be formed. A photoresist (not shown) is formed. Using this photoresist as a mask, Ti and Au are sequentially deposited by vapor deposition. Thus, the metal film 20 is formed on the annular electrode 18 and on the second wiring 40 in the region where the protruding electrode 30 is to be formed. The metal film 20 and the first wiring 34 are electrically separated by an insulator 36. Thereafter, the photoresist is removed.

  As shown in FIG. 4D, after the photoresist 48 is applied on the substrate 10, the photoresist 48 on the annular electrode 18 and the second wiring 40 in the region where the protruding electrode 30 is to be formed is removed. The opening 50 is formed.

  As shown in FIG. 4E and FIG. 8B, Ni and Au are sequentially formed on the annular wiring 18 and the second wiring 40 in the region where the protruding electrode 30 is to be formed by using an electrolytic plating method. Grow. Thereby, the frame 22 surrounding the two surface acoustic wave elements 12 connected in series and the lower portion 32a of the protruding electrode 30 electrically connected to the surface acoustic wave element 12 are formed simultaneously. Thereafter, the photoresist 48 is removed. Since the frame 22 and the lower portion 32a of the protruding electrode 30 are simultaneously formed by the electrolytic plating method, they are made of the same metal and have the same thickness.

  FIG. 10 is a top view showing a cutting region formed on the wafer-like substrate 10. As shown in FIG. 10, on the surface of the wafer-like substrate 10, a cutting region in which the fourth wiring 44 is formed is formed in a mesh shape. As shown in FIG. 8B, the second wiring 40 formed in the region where the protruding electrode 30 is to be formed is electrically connected to the fourth wiring 44, and the annular wiring 18 is connected to the fourth wiring via the third wiring 42. The wiring 44 is electrically connected. For this reason, by connecting an electrode for electrolytic plating to the outer peripheral portion of the wafer-like substrate 10, a current is passed through the annular wiring 18 and the second wiring 40 through the fourth wiring 44 over the entire surface of the wafer. The frame body 22 and the lower portion 32a of the protruding electrode 30 can be formed simultaneously. Thus, the 2nd wiring 40, the 3rd wiring 42, and the 4th wiring 44 are used as a feed line for plating used by an electrolytic plating method.

  As shown in FIG. 5A, a metal plate 52 made of Cu having Sn formed on the surface is prepared in advance. While the metal plate 52 is pressed against the upper surface of the frame 22 and the upper surface of the lower portion 32a of the protruding electrode 30 using the support plate 54, the temperature at which Sn formed on the surface of the metal plate 52 melts (for example, 200 ° C.). Thereby, Sn formed on the surface of the metal plate 52 is melted, and the metal plate 52, the frame body 22, and the lower portion 32a of the protruding electrode 30 are joined. That is, the brazing material 28 made of Sn is formed between the metal plate 52 and the frame body 22 and the lower portion 32 a of the protruding electrode 30. The frame body 22 and the lower portion 32a of the protruding electrode 30 are a laminated film of Ni and Au, and this Au is provided in order to improve the adhesion with Sn. Therefore, the frame 22 and the lower portion 32a of the protruding electrode 30 are preferably formed by stacking Au on Ni, but may be formed by a single layer of Ni without being stacked. By joining the metal plate 52 to the upper surface of the frame body 22, the surface acoustic wave element 12 can be sealed with the cavity 24 on the surface acoustic wave element 12.

  As shown in FIG. 5B, after the support plate 54 is removed, an insulator 38 covering the first wiring 34 and the like is formed by pouring a resin such as an epoxy resin from the end of the wafer-like substrate 10. At this time, since the frame body 22 is provided so as to surround the surface acoustic wave element 12, it is possible to prevent a resin such as an epoxy resin from flowing into the surface acoustic wave element 12.

  As shown in FIG. 5C, after the photoresist 56 is applied on the metal plate 52, the photoresist 56 in the region other than the region where the lid 26 and the protruding electrode 30 are to be formed is removed to form the opening 58. To do. The metal plate 52 exposed at the opening 58 is etched using the photoresist 56 as a mask. Etching may be either wet etching or dry etching. Thereby, the lid | cover 26 on the frame 22 and the upper part 32b of the protruding electrode 30 are formed simultaneously.

  As shown in FIGS. 5D and 9, after removing the photoresist 56, the cutting region in which the fourth wiring 44 is formed is cut using, for example, dicing, and a plurality of acoustic wave devices are separated into pieces. To do. FIG. 9 is a perspective view of the insulator 38. Since the fourth wiring 44 is removed by this separation, the second wiring 40 and the third wiring 42 respectively connected to the fourth wiring 44 can be electrically separated. Since the insulator 36 is provided between the first wiring 34 and the frame body 22, the frame body 22, the lid 26, and the protrusion are electrically separated from the second wiring 40 and the third wiring 42. The electrode 30 can be electrically separated. Thereby, the acoustic wave device according to the first embodiment is completed.

  According to the first embodiment, as shown in FIGS. 1A and 1B, a frame 22 made of metal is provided so as to surround the surface acoustic wave element 12. On the frame 22, a lid 26 made of metal having a cavity 24 on the surface acoustic wave element 12 is provided. Thereby, since the surface acoustic wave element 12 is sealed by the metal sealing portion (the frame body 22 and the lid 26), the moisture resistance is improved. Further, since the sealing portion (the frame body 22 and the lid 26) is a wafer level package provided on the substrate 10, it is possible to realize a reduction in size and height. Therefore, according to Example 1, an elastic wave device having a small size, a low profile, and good moisture resistance can be obtained.

  As shown in FIG. 5C, a metal plate 52 is joined on the frame body 22, and the metal plate 52 is etched and removed, whereby the surface of the surface acoustic wave element 12 is formed on the frame body 22. A lid 26 having a cavity 24 is formed. Thereby, the position shift between the frame 22 and the lid | cover 26 can be suppressed. Therefore, it is possible to suppress deterioration of moisture resistance due to a positional shift caused by a difference in linear expansion coefficient between the frame body 22 and the lid 26.

  As shown in FIGS. 4E and 8B, the frame body 22 and the lower portion 32a of the protruding electrode 30 are simultaneously formed by an electrolytic plating method. As shown in FIG. 5C, the metal plate 52 bonded on the frame 22 and the lower portion 32 a of the protruding electrode 30 is etched so that the upper side of the protruding electrode 30 is simultaneously formed with the lid 26. A portion 32b is formed. Thereby, since the sealing part (the frame body 22 and the lid | cover 26) which seals the surface acoustic wave element 12 can be simultaneously formed with respect to each of several elastic wave device, manufacturing cost can be reduced.

  Further, since the frame body 22 and the lower portion 32a of the protruding electrode 30 are simultaneously formed by electrolytic plating, they are formed of the same metal and have the same thickness. Similarly, since the lid 26 and the upper portion 32b of the protruding electrode 30 are simultaneously formed by etching the metal plate 52, they are formed of the same metal and have the same thickness. That is, the height from the substrate 10 to the upper surface of the lid 26 is the same as the height from the substrate 10 to the upper surface of the protruding electrode 30. Since the height from the board | substrate 10 to the upper surface of the lid | cover 26 and the upper surface of the protruding electrode 30 is the same, the protruding electrode 30 can be stably connected to the electrode of mounting parts, such as a printed circuit board. Further, at the same time when the protruding electrode 30 is connected to the electrode of the mounting portion, the lid 26 can be connected to the ground potential portion of the mounting portion. Therefore, the frame body 22 and the lid 26 can be set to the ground potential.

  Further, since the frame body 22 and the lower portion 32a of the protruding electrode 30 are formed of the same metal, the metal plate 52 is bonded to the frame body 22 and the lower portion 32a of the protruding electrode 30 under the same conditions. In addition, since the height is the same, the metal plate 52 can be easily joined. The frame body 22 and the lower portion 32a of the protruding electrode 30 may include Cu in addition to Ni. When Ni is included, the corrosion resistance can be improved, and when Cu is included, the resistivity can be improved. Note that Sn may not be formed on the surface of the metal plate 52 but Sn may be formed on the surface of Ni or Cu. Even in this case, the metal plate 52, the frame body 22, and the lower portion 32a of the protruding electrode 30 can be joined.

  As shown in FIG. 5A, a metal plate 52 made of Cu having Sn formed on the surface thereof is bonded to the frame 22 and the lower portion 32 a of the protruding electrode 30. Therefore, as shown in FIG. 1B, the brazing material 28 made of Sn is formed between the frame body 22 and the lid 26 and between the lower portion 32a and the upper portion 32b of the protruding electrode 30. The The metal formed on the surface of the metal plate 52 is not limited to Sn, and any other metal may be used as long as it has a lower melting point than the frame 22, the lower portion 32a of the protruding electrode 30, and the metal plate 52. A metal may be used. That is, the brazing material 28 provided between the frame body 22 and the lid 26 and between the lower portion 32a and the upper portion 32b of the protruding electrode 30 may be other than Sn.

  As shown in FIG. 5B, after forming the frame body 22 and before etching the metal plate 52, an insulator such as a resin is poured from the end of the substrate 10 to be positioned outside the frame body 22. An insulator 38 that covers the first wiring 34 and the like is formed. As a result, as shown in FIG. 5C, the first wiring 34 and the like can be protected in the step of etching the metal plate 52. Moreover, since the insulator 38 is formed on the outer side of the frame body 22, it is possible to suppress moisture and the like from entering the inside of the frame body 22 from the side of the frame body 22 and to further improve the moisture resistance.

  As shown in FIGS. 5 (d) and 9, simultaneously with the separation of the surface acoustic wave elements 12 connected in series, the feeding wire for plating is cut, and the separated surface acoustic wave elements 12 are electrically connected. It is preferable to electrically separate the protruding electrode 30 and the frame body 22 surrounding the separated surface acoustic wave element 12 from each other. As a result, a separate step of electrically separating the protruding electrode 30 and the frame body 22 is not required, and the number of manufacturing steps can be reduced. As the power supply line for plating, as shown in FIG. 8B, the fourth wiring 44 formed in the cutting region and the second wiring 40 extending from the fourth wiring 44 to the region where the protruding electrode 30 is to be formed. And a third wiring 42 extending from the fourth wiring 44 to a region where the frame body 22 is to be formed. As described above, the second wiring 40 extending to the region where the protruding electrode 30 is to be formed and the third wiring 42 extending to the region where the frame body 22 is to be formed are commonly connected to the fourth wiring. 44 is preferably formed as separate wiring. Thereby, the protruding electrode 30 and the frame body 22 can be electrically separated by cutting the fourth wiring 44 simultaneously with the separation of the surface acoustic wave elements 12.

  In the first embodiment, as shown in FIG. 1A, all of a plurality of portions where the first wiring 34 and the frame body 22 intersect are formed as a three-dimensional wiring structure, and the first wiring 34 and the frame body 22 are electrically separated. Although the case where it does is shown as an example, it is not necessarily restricted to this. When the first wiring 34 connected to the signal input / output projecting electrode 30 and the frame body 22 are electrically connected, it is difficult to obtain satisfactory electrical characteristics, but the first wiring 34 is connected to the ground projecting electrode 30. Even if the first wiring 34 and the frame 22 are electrically connected, satisfactory electrical characteristics can be obtained. Therefore, if the portion where the first wiring 34 connected to the signal input / output projection electrode 30 intersects the frame 22 is a three-dimensional wiring structure, the first wiring 34 connected to the ground projection electrode 30 and The portion where the frame 22 intersects may not be a three-dimensional wiring structure. In this case, the frame body 22 and the lid 26 can be set to the ground potential.

  Further, as shown in FIG. 2, an example in which an insulator 36 is provided between the first wiring 34 and the frame body 22 as a three-dimensional wiring structure is shown, but the first wiring 34 and the frame body 22 are As long as these are electrically separated, other three-dimensional wiring structures may be used. For example, a three-dimensional wiring structure that intersects three-dimensionally with air interposed between the first wiring 34 and the frame body 22 may be used.

  The insulator 36 provided at the portion where the first wiring 34 and the frame body 22 intersect each other is made of a photosensitive resin such as polyimide, and is not a photosensitive resin or an inorganic type such as silicon oxide or silicon nitride. The insulator may be used. However, by using a photosensitive resin, the insulator 36 can be easily formed at a portion where the first wiring 34 and the frame body 22 intersect by coating, exposure, and development.

  In the first embodiment, the case of the surface acoustic wave device in which the two surface acoustic wave elements 12 are connected in series is shown as an example, but in the case of the surface acoustic wave device in which a plurality of surface acoustic wave elements are connected in a ladder shape, An elastic wave device having another configuration may be used. Accordingly, the frame body 22 is not limited to surrounding two surface acoustic wave elements 12 connected in series, and may surround a plurality of surface acoustic wave elements, or may surround one surface acoustic wave element. Good.

  As the acoustic wave element, in addition to the surface acoustic wave element 12, a piezoelectric thin film resonant element may be used. In the case of a piezoelectric thin film resonant element, the substrate 10 may be a substrate having no piezoelectricity, such as a silicon substrate, a glass substrate, or a quartz substrate.

  Although the embodiments of the present invention have been described in detail above, the present invention is not limited to such specific embodiments, and various modifications and changes can be made within the scope of the gist of the present invention described in the claims. It can be changed.

DESCRIPTION OF SYMBOLS 10 Substrate 12 Surface acoustic wave element 18 Annular wiring 20 Metal film 22 Frame 24 Cavity 26 Lid 28 Brazing material 30 Protruding electrode 32a Lower part of protruding electrode 32b Upper part of protruding electrode 34 First wiring 36 Insulator 38 Insulator 40 Second wiring 42 Third wiring 44 Fourth wiring 52 Metal plate

Claims (10)

An acoustic wave device provided on a substrate;
Wiring provided on the substrate and electrically connected to the acoustic wave element;
A frame made of metal that is provided on the substrate so as to surround the acoustic wave element, intersects with the wiring, and is electrically separated from the wiring;
An elastic wave device comprising: a lid made of metal provided on the elastic body and having a cavity on the elastic wave element. Provided on the substrate outside the frame, and provided with a protruding electrode electrically connected to the wiring,
2. The acoustic wave device according to claim 1, wherein the protruding electrode has a lower portion made of the same metal as the frame body and an upper portion made of the same metal as the lid.   3. The acoustic wave device according to claim 2, wherein a height from the upper surface of the substrate to the upper surface of the lid is the same as a height from the upper surface of the substrate to the upper surface of the protruding electrode.   4. The acoustic wave device according to claim 1, wherein a first insulator that covers the wiring located outside the frame body is provided. 5.   The elastic wave device according to claim 1, wherein a brazing material is provided between the frame and the lid.   The acoustic wave device according to claim 1, wherein a second insulator is provided between the wiring and the frame. A step of forming an acoustic wave element and a wiring electrically connected to the acoustic wave element on a substrate;
Forming a frame made of metal that surrounds the acoustic wave element on the substrate, intersects the wiring, and is electrically separated from the wiring;
Joining a metal plate on the frame;
Forming a lid made of a metal having a cavity on the elastic wave element on the frame by performing an etching process on the metal plate, and manufacturing an elastic wave device Method. Forming a protruding electrode electrically connected to the wiring on the substrate outside the frame;
The frame and the lower portion of the protruding electrode are simultaneously formed by electrolytic plating,
The upper part of the protruding electrode is formed at the same time as the lid by bonding the metal plate on the frame and the lower part of the protruding electrode and then etching the metal plate. The method for manufacturing an acoustic wave device according to claim 7, wherein: A plurality of the acoustic wave elements are formed on the substrate,
Simultaneously with the separation of the plurality of acoustic wave elements, the protruding electrodes electrically connected to the separated acoustic wave elements by cutting the plating feeder used in the electrolytic plating method; The method for manufacturing an acoustic wave device according to claim 8, further comprising a step of electrically separating the frame body surrounding the separated acoustic wave element.   10. The method according to claim 7, further comprising a step of pouring an insulator from an end of the substrate so as to cover the wiring after forming the frame body and before etching the metal plate. A method for manufacturing an acoustic wave device according to one item.

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