LAMINATED ACOUSTIC WAVE (AW) FILTER PACKAGE INCLUDING CROSSTALK REDUCTION LAYER AND ASSOCIATED MANUFACTURING METHOD - Patent application

Abstract

The laminated AW filter package (200) includes a first substrate (204) laminated on a second substrate. The first substrate has a first AW filter circuit (202) on a first surface (212) and a metal layer (210) on a second surface. The second substrate has a second AW filter circuit (206) disposed in a cavity between the metal layer (210) of the first substrate (204) and a third surface of the second substrate. The metal layer (210) is coupled to the second AW filter circuit (206) by a metal interconnect (230a) formed in a metallization layer on a side of the first substrate. The metal layer (210) provides isolation between the first AW filter circuit (202) and the second AW filter circuit (206) to reduce crosstalk (e.g., electromagnetic interference) within the laminated AW filter package (200). The inclusion of the metal layer (210) in the laminated AW filter package (200) improves the signal quality of the transmit and receive signals filtered in the first and second AW filter circuits (202, 206).

Description

[Technical field]

[0001] Priority Application

[0001] This application claims priority to U.S. patent application Ser. No. 17 / 649,965, entitled "STACKED ACOUSTIC WAVE (AW) FILTER PACKAGES, INCLUDING CROSS-TALK REDUCTION LAYERS, AND RELATED FABRICATION METHODS," filed on February 4, 2022, the entire contents of which are incorporated by reference into this specification.

[0002] I. Field of Disclosure The technology disclosed herein generally relates to an acoustic wave (AW) filter package that includes an AW filter having an AW filter circuit on a substrate. [Background technology]

[0003] II. Background

[0003] A smartphone is an example of a mobile device that includes multiple transmitters and receivers for multiple wireless interfaces, including cellular telephone communication, Bluetooth, and Wi-Fi. The cellular telephone interface of such a mobile device may include multiple wireless interfaces, each including a transmitter and a receiver. Each wireless interface is designed to transmit and receive radio-frequency (RF) analog signals within a specific non-overlapping frequency range (band). Because signals outside the frequency band designated for a particular interface may interfere with communications, the transmitters and receivers may include filters to filter out signals outside the corresponding frequency range before transmission and after reception.

[0004]

[0004] An acoustic wave (AW) filter is a type of filter that can be used to remove undesired frequencies in a signal. AW filters use piezoelectric materials to convert analog electrical signals into acoustic waves, which are filtered in a solid propagation medium, and then converted back from the filtered acoustic waves to analog signals. Because there can be multiple transmitters and receivers in multiple wireless interfaces, each containing an AW filter, a mobile device can include multiple AW filters in an AW filter package. Because AW filters can be formed on a semiconductor (e.g., silicon) substrate, existing semiconductor processing techniques can be used to manufacture the AW filter package.

[0005]

[0005] Multiple AW filters can be formed on a single substrate to reduce the cost and space occupied by the AW filter package.To further reduce the cost and volume of the AW filter package, one substrate containing one or more AW filters can be stacked (e.g., vertically) on another substrate containing one or more AW filters in a stacked AW filter package.However, integrating multiple AW filters into a single AW filter package can be problematic. Summary of the Invention

[0006]

[0006] Aspects disclosed in the detailed description include a laminated acoustic wave (AW) filter package including a crosstalk reduction layer. Related methods of manufacturing such a laminated AW filter package are also disclosed. The laminated AW filter package includes a first substrate laminated on a second substrate. The first substrate has a first AW filter circuit on a first surface and a metal layer on a second surface. The second substrate has a second AW filter circuit disposed in a cavity between the metal layer of the first substrate and a third surface of the second substrate. The metal layer is coupled to the second AW filter circuit by a metal interconnect formed in a metallization layer on a side of the first substrate. The metal layer provides isolation between the first AW filter circuit and the second AW filter circuit to reduce crosstalk (e.g., electromagnetic interference) in the laminated AW filter package between the first AW filter circuit and the second AW filter circuit. For example, crosstalk may occur or be noticeable between the first and second AW filter circuits in the laminated AW filter package, especially when the first and second AW filter circuits are coupled to the same signal source. The inclusion of a metal layer in the laminated AW filter package provides an electromagnetic shield that reduces the transmission of crosstalk between the first and second AW filter circuits. In this regard, the inclusion of a metal layer improves the signal quality of the transmit and receive signals filtered in the first and second AW filter circuits.

[0007]

[0007] In some exemplary embodiments, the metal layer is coupled to a ground pad coupled to the second AW filter circuit. In other exemplary embodiments, a portion of the metal layer of the first substrate extends onto a side of the first substrate to couple to a metal interconnect in the metallization layer. In some examples, an insulating layer is disposed on the side of the first substrate, and a second metal interconnect coupled to the second AW filter circuit is disposed on the insulating layer and electrically isolated from the first substrate.

[0008]

[0008] In one exemplary aspect, a laminated acoustic wave (AW) filter package is provided. The laminated AW filter package includes a first substrate having a first AW filter circuit on a first surface thereof and a metal layer on a second surface of the first substrate. The AW filter package also includes a second substrate having a second AW filter circuit on a third surface thereof, the second AW filter circuit being disposed in a cavity between the metal layer on the first substrate and the third surface of the second substrate. The laminated AW filter package also includes a metallization layer including at least one metal interconnect disposed on a side surface of the first substrate, the at least one metal interconnect being coupled to the metal layer and the second AW filter circuit.

[0009]

[0009] In another exemplary aspect, a method for manufacturing a laminated AW filter package is disclosed. The method includes forming a first AW filter circuit on a first surface of a first substrate and forming a metal layer on a second surface of the first substrate. The method further includes forming a second AW filter circuit on a third surface of a second substrate and forming a cavity around the second AW filter circuit between the metal layer and the third surface of the second substrate. The method also includes at least one metal interconnect on a side of the first substrate, the at least one metal interconnect being coupled to the metal layer and the second AW filter circuit. [Brief description of the drawings]

[0010] [Figure 1A]

[0010] FIG. 1 is a perspective view of an example of an electroacoustic device that can be used as an acoustic wave (AW) filter. [Figure 1B]

[0011] FIG. 1B is a side view of the electroacoustic device of FIG. 1A. [Figure 2A]

[0012] FIG. 1 is an illustrative side view of a cross section through a ground pin and a signal pin, respectively, of an exemplary laminated AW filter package including a metal layer for reducing crosstalk between a first AW filter circuit on a first substrate and a second AW filter circuit on a second substrate. [Figure 2B]FIG. 1 is an illustrative side view of a cross section through a ground pin and a signal pin, respectively, of an exemplary laminated AW filter package including a metal layer for reducing crosstalk between a first AW filter circuit on a first substrate and a second AW filter circuit on a second substrate. [Diagram 3]

[0013] FIG. 1 is a perspective view of a laminated AW filter package, illustrating an example stage of fabrication with one metal interconnect on a side of a first substrate bonded to a metal layer and another metal interconnect insulated from the metal layer. [Figure 4]

[0014] 4 is a perspective view of the laminated AW filter package of FIG. 3 at an exemplary stage of manufacture, illustrating a side view and a cross-sectional side view of the second side of the first substrate and a metal layer on a side of the substrate. [Diagram 5]

[0015] FIG. 5 is a perspective view of the laminated AW filter package of FIG. 4 at another exemplary stage of manufacture, illustrating an insulating layer disposed on a side of the first substrate and patterned to expose a portion of the metal layer extending over the side. [Figure 6]

[0016] 6 is a flow chart illustrating an example process for manufacturing a laminated AW filter package including a metal layer for reducing crosstalk between a first AW filter circuit on a first substrate and a second AW filter circuit on a second substrate, including the laminated AW filter package of FIGS. 2A-5. [Figure 7A]

[0017] 6 is a flow chart illustrating another exemplary manufacturing process for producing the laminated AW filter package of FIGS. 2A-5. [Figure 7B] 6 is a flow chart illustrating another exemplary manufacturing process for producing the laminated AW filter package of FIGS. 2A-5. [Figure 7C] 6 is a flow chart illustrating another exemplary manufacturing process for producing the laminated AW filter package of FIGS. 2A-5. [Figure 7D] 6 is a flow chart illustrating another exemplary manufacturing process for producing the laminated AW filter package of FIGS. 2A-5. [Figure 8A]

[0018] 7A-7D illustrate exemplary manufacturing stages during the manufacture of the laminated AW filter package of FIGS. 2A-5 according to the exemplary manufacturing process of FIGS. [Figure 8B] 7A-7D illustrate exemplary manufacturing stages during the manufacture of the laminated AW filter package of FIGS. 2A-5 according to the exemplary manufacturing process of FIGS. [Figure 8C] 7A-7D illustrate exemplary manufacturing stages during the manufacture of the laminated AW filter package of FIGS. 2A-5 according to the exemplary manufacturing process of FIGS. [Figure 8D] 7A-7D illustrate exemplary manufacturing stages during the manufacture of the laminated AW filter package of FIGS. 2A-5 according to the exemplary manufacturing process of FIGS. [Figure 9]

[0019] FIG. 2A is a block diagram of an exemplary wireless communication device including a radio-frequency integrated circuit (RFIC) including a laminated AW filter package including a first AW filter on a first surface of a first substrate, a metal layer on a second surface of the first substrate, and a second AW filter between the metal layer and the second substrate, where the metal layer reduces crosstalk between the first AW filter circuit and the second AW filter circuit, including the laminated AW filter package of FIGS. 2A-5 and 8A-8D. [Figure 10]

[0020] FIG. 2A is a block diagram of an exemplary processor-based system that may include an RFIC including a stacked AW filter package including a first AW filter on a first surface of a first substrate, a metal layer on a second surface of the first substrate, and a second AW filter between the metal layer and the second substrate, where the metal layer reduces crosstalk between the first AW filter circuit and the second AW filter circuit, including the stacked AW filter packages of FIGS. 2A-5 and 8A-8D. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011]

[0021] Some exemplary aspects of the present disclosure will now be described with reference to the drawings. The word "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any aspect described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other aspects.

[0012]

[0022] Aspects disclosed in the detailed description include a laminated acoustic wave (AW) filter package including a crosstalk reduction layer. Related methods of manufacturing the laminated AW filter package are also disclosed. The laminated AW filter package includes a first substrate laminated on a second substrate. The first substrate has a first AW filter circuit on a first surface and a metal layer on a second surface. The second substrate has a second AW filter circuit disposed in a cavity between the metal layer of the first substrate and a third surface of the second substrate. The metal layer is coupled to the second AW filter circuit by a metal interconnect formed in a metallization layer on a side of the first substrate. The metal layer provides separation between the first AW filter circuit and the second AW filter circuit to reduce crosstalk (e.g., electromagnetic interference) in the laminated AW filter package. Including a metal layer in the laminated AW filter package improves signal quality of transmit and receive signals filtered in the first and second AW filter circuits. In some examples, the metal layer is coupled to a ground pad coupled to the second AW filter circuit. In other examples, portions of the metal layer extend onto a side of the first substrate and couple to metal interconnects in the metallization layer, while in other examples, an insulating layer is disposed on a side of the first substrate and a second metal interconnect coupled to the second AW filter circuit is disposed on the insulating layer and is electrically isolated from the first substrate.

[0013]

[0023] Before discussing exemplary embodiments of a laminated AW filter package that includes a metal layer on a bottom surface of a first substrate to reduce crosstalk between a first AW filter circuit on a first substrate and a second AW filter circuit on a second substrate, as illustrated in FIGS. 2A-5 and 8A-8D, an example of a conventional surface AW (SAW) filter 100 will be discussed with reference to FIGS. 1A and 1B.

[0014]

[0024] 1A is a perspective view of an example of an electroacoustic device 100. The electroacoustic device 100 may be configured as or may be part of a SAW resonator. In certain descriptions herein, the electroacoustic device 100 may be referred to as a SAW resonator. However, there may be other electroacoustic device types (e.g., BAW or TFBAR) that may be constructed based on the principles described herein, any of which may be incorporated into an AW filter. The electroacoustic device 100 includes an electrode structure 104, which may be referred to as an interdigital transducer (IDT), on a surface of a piezoelectric material 102. The electrode structure 104 generally includes first and second interdigitated electrode structures (which are conductive and generally metallic) with electrode fingers extending from two bus bars toward each other and disposed in an interlocking manner (e.g., disposed in an interdigitated manner) between the two bus bars. An electrical signal excited at the electrode structure 104 (e.g., applying an AC voltage) is converted into an acoustic wave 106 that propagates in a particular direction through the piezoelectric material 102. The acoustic wave 106 is converted back into an electrical signal and provided as an output. In many applications, the piezoelectric material 102 has a particular crystal orientation such that when the electrode structure 104 is disposed relative to the crystal orientation of the piezoelectric material 102, the acoustic waves propagate primarily in a direction perpendicular to the direction of the fingers (e.g., parallel to the busbars).

[0015]

[0025] FIG. 1B is a side view of the electroacoustic device 100 of FIG. 1A along the cross section 107 shown in FIG. 1A. The electroacoustic device 100 is illustrated by a simplified layer stack including a piezoelectric material 102 with an electrode structure 104 disposed thereon. The electrode structure 104 is electrically conductive and is generally formed from a metallic material. The piezoelectric material may be formed from a variety of materials such as quartz, lithium tantalate (LiTaO3), lithium niobate (LiNbO3), doped variants thereof, or other piezoelectric materials. It should be understood that more complex layer stacks including layers of various materials may be possible within the stack. For example, optionally, a temperature compensation layer 108, shown in dashed lines, may be disposed over the electrode structure 104. The piezoelectric material 102 may extend with multiple interconnected electrode structures disposed thereon to form a multi-resonator filter or provide multiple filters. Although not illustrated, if provided as an integrated circuit component, a cap layer may be provided over the electrode structure 104. The cap layer is applied such that a cavity is formed between the electrode structure 104 and the underside of the cap layer. Electrical vias or bumps may also be included to allow the components to be electrically connected (e.g., via flip chip or other techniques) to connections on the substrate.

[0016]

[0026] 2A and 2B are cross-sectional side-view illustrations of an exemplary laminated AW filter package 200 including a first AW filter circuit 202 stacked on a first substrate 204 and a second AW filter circuit 206 stacked on a second substrate 208 to provide multiple AW filters. Each of the first substrate 204 and the second substrate 208 may include one or more electro-acoustic devices similar to the electro-acoustic device 100 of FIG. 1 as part of the AW filter circuit in the AW filter. As will be discussed in more detail below, the laminated AW filter package 200 includes a metal layer 210 for reducing crosstalk between the first AW filter circuit 202 on the first substrate 204 and the second AW filter circuit 206 on the second substrate 208. FIG. 2A is a cross-sectional side view of the laminated AW filter package 200 through a ground pad 242. FIG. 2B is a cross-sectional side view of the laminated AW filter package 200 through a signal pad 246. The laminated AW filter package 200 will now be described with reference to the cross-sectional side views of FIGS. 2A and 2B.

[0017]

[0027] In this regard, as shown in Figures 2A and 2B, the AW filter package 200 includes a first AW filter circuit 202 on a first substrate 204 and a second AW filter circuit 206 on a second substrate 208 stacked vertically (Z-axis direction) on the first AW filter circuit 202. The first AW filter circuit 202 and the second AW filter circuit 206 are collectively referred to herein as "first and second AW filter circuits 202, 206." The first AW filter circuit 202 and the second AW filter circuit 206 may each correspond to the SAW filter circuit 102 of Figure 1, but may be any other type or configuration of AW filter circuit. Accordingly, details of the first AW filter circuit 202 and the second AW filter circuit 206 are not shown in Figures 2A or 2B. The first and second AW filter circuits 202, 206 include a first metal interconnect for receiving an input RF signal from an external circuit (eg, an antenna) and providing a filtered RF signal as an output to the external circuit.

[0018]

[0028] In the AW filter package 200 of FIGS. 2A and 2B, the first AW filter circuit 202 is disposed on a first surface 212 of a first substrate 204. For example, the first substrate 204 may be formed from a semiconductor material (e.g., silicon) formed in a wafer to take advantage of advances in semiconductor processing technology and low cost. A metal layer 210 is disposed on a second surface 214 of the first substrate 204 to reduce crosstalk between the first AW filter circuit 202 and the second AW filter circuit 206. The second surface 214 is opposite the first surface 212. In the orientation of the AW filter package 200 shown in FIG. 2, the first surface 212 may also be referred to as a top surface 212 and the second surface 214 may also be referred to as a bottom surface 214 of the first substrate 204, because the top surface 212 is disposed above the bottom surface 214 in the vertical direction (Z-axis direction).

[0019]

[0029] 2A and 2B, the second AW filter circuit 206 is disposed in or on the third surface 216 of the second substrate 208. The first substrate 204 is stacked on the second substrate 208 in the AW filter package 200 to minimize the area occupied by the AW filter circuit on the first and second substrates 204, 208. The second substrate 208 may also be formed from a semiconductor material (e.g., silicon) formed in a wafer, for example, to take advantage of advances in semiconductor processing technology and lower costs. In this regard, the first substrate 204 may be stacked on the second substrate 208 (e.g., vertically upward in the Z-axis direction), and the second substrate 208 may be stacked on the first substrate 204 (e.g., vertically downward in the Z-axis direction). The frame 218 is disposed between the metal layer 210 on the second substrate 214 of the first substrate 204 and the surface 216 of the second substrate 208. The second AW filter circuit 206 is disposed in a cavity 220 between the metal layer 210 and the surface 216 of the second substrate 208. The cavity 220 may also contain air or gas. The cavity 220 prevents external interference with the propagation of acoustic waves in the second AW filter circuit 206.

[0020]

[0030] The AW filter package 200 of FIGS. 2A and 2B also includes a cap substrate 222 disposed on the first surface 212 of the first substrate 204. The cap substrate 222 is separated from the first surface 212 by a frame 224 to form a cavity 226 in which the first AW filter circuit 202 is disposed. The cap substrate 222 provides a cap for the cavity 220 in the manner in which the first substrate 204 provides a cap for the cavity 226. The cavity 226 also contains air or another gas around the first AW filter circuit 202. The cap substrate 222 can be, for example, glass, or another non-conductive substrate material. The laminated AW filter package 200 also includes contacts 228A, 228B disposed on metal interconnects 230A, 230B on a contact surface 232 of the cap substrate 222 to connect the second AW filter circuit 206 to an external circuit. The contacts 228A, 228B are coupled to the second AW filter circuit 206 by metal interconnects 230A, 230B formed in a metallization (redistribution) layer 236. The metallization layer 236 extends from the contact surface 232 onto a side surface 238 of the cap substrate 204 and onto a side surface 240 of the first substrate 204. The side surface 240 extends between the first surface 212 and the second surface 214 of the first substrate 204. Additional contacts (not shown) may be disposed on the contact surface 232 to connect the first AW filter circuit 202 to an external circuit.

[0021]

[0031] In the stacked AW filter package 200 of Figures 2A and 2B, the first AW filter circuit 202 filters a first RF signal and the second AW filter circuit 206 filters another RF signal. In some examples, the first and second AW filter circuits 202, 206 are not electrically associated with each other during operation, while in other examples, the first and second AW filter circuits 202, 206 may both be coupled to the same antenna (not shown) coupled to the AW filter package 200. Thus, the first and second AW filter circuits 202, 206 may provide different filters for the same RF signal or may filter different RF signals. Time-varying voltages generated in each of the first and second AW filter circuits 202, 206 may cause crosstalk or noise from electromagnetic interference (EMI) and cause undesirable fluctuations in signals in nearby circuits.

[0022]

[0032] Although the magnitude of EMI attenuates with distance, because the first and second AW filter circuits 202, 206 are in close proximity to one another within the AW filter package 200, noise generated in the first AW filter circuit 202 can interfere with the operation of the second AW filter circuit 206, and noise generated in the second AW filter circuit 206 can interfere with the signal of the first AW filter circuit 202. Crosstalk can be particularly problematic when the first AW filter circuit 202 and the second AW filter circuit 206 are coupled to the same antenna.

[0023]

[0033] The metal layer 210 is included because it blocks or at least reduces the transmission of some of the crosstalk between the first AW filter circuit 202 and the second AW filter circuit 206, reducing noise and improving signal quality. In this example, the metal layer 210 is disposed between the first AW filter circuit 202 and the second AW filter circuit 206 to reduce crosstalk between them, as discussed in more detail below. The shielding provided by the metal layer 210 may be beneficial between any two AW filter circuits in the stacked AW filter package 200, and may be particularly beneficial in devices in which the first AW filter circuit 202 and the second AW filter circuit 206 are coupled to the same antenna (not shown). Crosstalk refers to EMI or noise that one circuit inadvertently induces on another circuit when the circuits are close enough together that the magnitude of the crosstalk is not attenuated and induces undesired signals on the affected circuit. Metal layer 210 acts as an electromagnetic shield (ie, a Faraday shield) to block the propagation of crosstalk between adjacent circuits.

[0024]

[0034] 2A is a cross-sectional view of a ground pad 242, which may also be known as a "landing pad," for metal interconnect 230A. As shown in FIG. 2A, metal interconnect 230A couples contact 228A to ground pad 242, which in turn couples to a ground circuit path (not shown) of second AW filter circuit 206. Contact 228A couples to a ground voltage V SS (e.g., 0 volts). Portion 244 of metal layer 210 extends from second surface 214 through frame 218 to side 240 of first substrate 204. Metal interconnect 230A formed on side 240 is provided to couple portion 244 of metal layer 210 to ground pad 242 of second AW filter circuit 206 on surface 216 of second substrate 208. There may be multiple portions 244 coupled to ground pad 242 to couple metal layer 210 to second AW filter circuit 206 at multiple locations on surface 216.

[0025]

[0035] A metal layer 210 is provided on the second surface 214 between the first AW filter circuit 202 and the second AW filter circuit 206 to reduce crosstalk between the first AW filter circuit 202 and the second AW filter circuit 206. The metal layer 210 may include two or more layers of metal for a total thickness of, for example, 2.5 microns, but may be thicker or thinner. For example, the metal layer 210 may include a layer of titanium (Ti) on the second surface 214 of the first substrate 204 and a layer of copper (Cu) formed on the layer of Ti. Bonding the metal layer 210 to the ground pad 242 in the second AW filter circuit 206 provides a shield (e.g., a Faraday shield) to isolate the first AW filter circuit 202 from the second AW filter circuit 206 and reduce crosstalk (e.g., electromagnetic interference) between the first AW filter circuit 202 and the second AW filter circuit 206. In this regard, metal layer 210 can improve the signal quality of signals transmitted from and received at a wireless device employing AW filter package 200.

[0026]

[0036] FIG. 2B is a cross-sectional view through the signal pad 246, provided to show the insulating layer 248 for insulating the metal interconnect 230B from the first substrate 204. In FIG. 2B, the metal interconnect 230B couples the contact 228B to the signal pad 246 carrying the signal of the second AW filter circuit 206 on the second substrate 208. The signal pad 246 may carry any signal of the second AW filter circuit 206. The metal layer 210 does not extend through the frame 218 onto the side 240 to couple to the metal interconnect 230B. The metal interconnect 230B is disposed on the insulating layer 248 disposed on the side 240 of the first substrate 204. The insulating layer 248 is between the metal interconnect 230B and the side 240 of the first substrate 204. The insulating layer 248 insulates the metal interconnect 230B from the first substrate 204, which may be formed from a semiconductor material. Bonding the metal interconnect 230B to the first substrate 204 may create a path for leakage current between the first AW filter circuit 202 and the metal interconnect 230B, which may cause power loss and interfere with operation. In some examples, an insulating layer 248 is also disposed on the side 238 of the cap substrate 222, on the frame 224, and on the first surface 212, and the metal interconnect 234B is disposed on the insulating layer 248.

[0027]

[0037] 2A, 2B, or 3-5, metal layer 210 may be a continuous metal layer, but may be patterned in any manner (e.g., with voids or slits) if desired to provide shielding in areas of second surface 214. In this regard, metal layer 210 may be disposed on a first portion of second surface 214, such as between the AW filter circuitry on first substrate 204 and the AW filter circuitry on second substrate 208, and not on a second portion of second surface 214 where the AW filter circuitry is not located.

[0028]

[0038] 3 is a perspective view of the AW filter package 200 shown in FIGS. 2A and 2B. FIG. 3 is provided to more clearly illustrate certain aspects of the AW filter package 200, in particular the metal interconnects 230A, 230B on the side 240 of the first substrate 204. As shown in this non-limiting example, the metal interconnect 230A extends from the contact 228A and is disposed on the side 238 of the cap substrate 222, on the frame 224, on the first surface 212 of the first substrate 204, on the portion 244 of the metal layer 210, and then on the frame 218 and the ground pad 242. The metal interconnect 230A couples the metal layer 210 and the second AW filter circuit 206 to the contact 228A. For example, the contact 228A may receive a ground voltage V from an external circuit in the mobile device. SS The metal interconnect 230B extends from the contact 228B and is disposed on the side 238 of the cap substrate 222, the insulating layer 248, the frame 218, and the signal pad 246. The metal interconnect 230B couples the signal pad 246 of the AW filter circuit 202 to the contact 228B, which may be coupled to at least one of the first AW filter circuit 206 and an external circuit.

[0029]

[0039] 2A, 2B, and 3 at an exemplary stage of manufacture prior to the formation of certain features in order to more clearly illustrate other features of AW filter package 200 that may not be apparent in previous views. AW filter package 200 in FIG. 4 does not include metal interconnects 230A, 230B of metallization layer 236, contacts 228A, 228B on contact surface 232, or insulating layer 248.

[0030]

[0040] FIG. 4 shows the side 240 of the first substrate 204 with a portion 244 of the metal layer 210 extending through the frame 218 on the side 240. Thus, on either side of the portion 244, the metal layer 210 does not extend through the frame 218, keeping the metal layer 210 isolated from other metal interconnects (e.g., 230B). To provide effective shielding, the metal layer 210 should be properly grounded to either the first AW filter circuit 202 or the second AW filter circuit 206. Coupling the metal layer 210 to the signal of the second AW filter circuit 206 may cause voltage fluctuations in the metal layer 210, which may contribute to crosstalk rather than mitigate it to the first AW filter circuit 202. FIG. 4 shows ground pads 242 and signal pads 246, which may be metal traces extending through the frame 218 on the surface 216 of the second substrate 208. The ground pad 242 and the signal pad 246 are merely examples of pads that are coupled to the second AW filter circuit 206 and are coupled to contacts, such as contacts 228A, 228B on the contact surface 232 of the cap substrate 222 for connection to external circuitry or the first AW filter circuit 202.

[0031]

[0041] 5 is a perspective view of the AW filter package 200 as shown in FIG. 4 at another exemplary stage of manufacture after an insulating layer 248 is disposed on the side 240 of the first substrate 204. The insulating layer 248 is formed on the first surface 212 and the side 240 of the first substrate 204 as previously described to insulate the first substrate 204 from the metal interconnect 230B (see FIG. 3) since the first substrate 204 may be a semiconductor. Bonding the metal interconnect 230B to the side 240 of the first substrate 204 may allow leakage current to flow between the first AW filter circuit 202 on the first substrate 204 and the metal interconnect 230B coupled to the second AW filter circuit 206. The insulating layer 248 is patterned to expose the portion 244 of the metal layer 210 that extends on the side 240 of the first substrate 204 so that the metal interconnect 230A can be bonded to the portion 244. An insulating layer 248 may be formed (e.g., deposited) and then patterned or etched. Although not shown in FIG. 5 for better visibility of the ground pads 242 and the signal pads 246, the insulating layer 248 may extend over the frame 218 and onto the surface 216 of the second substrate 208 to insulate the second substrate 208 from the metal interconnects 230B. The insulating layer 248 may also extend across the frame 224, onto the side surface 238 of the cap substrate 222, and onto the contact surface 232.

[0032]

[0042] An exemplary manufacturing process 600 for manufacturing the AW filter package 200 shown in Figures 2A-5 is illustrated in Figure 6. The process 600 includes forming a first AW filter circuit 202 on the first surface 212 of the first substrate 204 (block 602). The manufacturing process 600 includes forming a metal layer 210 on the second surface 214 and the side surface 240 of the first substrate 204 (block 604). The process 600 also includes forming a second AW filter circuit 206 on the third surface 216 of the second substrate 208 (block 606). The process 600 further includes forming a cavity 220 around the second AW filter circuit 206 between the metal layer 210 and the third surface 216 of the second substrate 208 (block 608). The process 600 further includes forming a second AW filter circuit (206) on a third surface (216) of the second substrate (208) (block 610).

[0033]

[0043] An exemplary manufacturing process 700 for forming the metal layer 210 is described with reference to FIGS. 7A-7D. The manufacturing stages of the process 700 are illustrated as manufacturing stages 800A-800D in FIGS. 8A-8D. In FIG. 7A, the process 700 includes forming a titanium layer 802 on the second surface 214 and the side surface 240 of the first substrate 204, and forming a copper layer 804 on the titanium layer 802 (block 702), as illustrated in manufacturing stage 800B of FIG. 8A. As described herein, the metal layer 210 is not limited to the titanium layer 802 and the copper layer 804. In this regard, the metal layer 210 may include fewer or more layers than the titanium layer 802 and the copper layer 804, and may include one or more other metals. The metal layer 210 may be formed by sputtering one or more metals on the second surface 214 and the side surface 240 of the first substrate 204. The formation of the metal layer 210 is not limited to sputtering. In Fig. 7B, forming the metal layer 210 further includes forming a resist layer 806 on the metal layer 210 (block 704), as illustrated in manufacturing stage 800B of Fig. 8B. For example, the resist layer 806 can be a photoresist polymer material 808.

[0034]

[0044] In FIG. 7C, forming the metal layer 210 further includes disposing a patterned mask 810 on the resist layer 806 and developing the resist layer 806 in the exposed areas 812 not covered by the patterned mask 810 (block 706), as illustrated in the manufacturing stage 800C of FIG. 8C. FIG. 8C shows the patterned mask 810 disposed on the metal layer 210 extending beyond the side surface 240 of the first substrate 204. In FIG. 7D, forming the metal layer 210 further includes removing the resist layer 806 in the exposed areas 812 and etching the metal layer 210 from the exposed areas 812 (block 708), in the manufacturing stage 800D of FIG. 8D. Forming the metal layer 210 may include additional manufacturing steps (not shown), such as developing the patterned mask and removing the resist material in the exposed areas 812 by the patterned mask 810.

[0035]

[0045] FIG. 9 illustrates an example wireless communication device 900 that includes RF components formed from one or more ICs 902 and may include a stacked AW filter package 903. The stacked AW filter package 903 includes a first AW filter circuit disposed on a first substrate, a second AW filter circuit disposed on a second substrate, and a metal layer for isolating the first AW filter circuit from the second AW filter circuit to reduce crosstalk, as illustrated in FIGS. 2A-5 and 8A-8D and according to any of the aspects disclosed herein. The wireless communication device 900 may include or be provided within any of the devices mentioned above, as examples. As shown in FIG. 9, the wireless communication device 900 includes a transceiver 904 and a data processor 906. The data processor 906 may include a memory for storing data and program codes. The transceiver 904 includes a transmitter 908 and a receiver 910 supporting bidirectional communication. In general, the wireless communication device 900 may include any number of transmitters 908 and / or receivers 910 for any number of communication systems and frequency bands. All or a portion of the transceiver 904 may be implemented on one or more analog ICs, RFICs, mixed-signal ICs, etc.

[0036]

[0046] The transmitter 908 or receiver 910 may be implemented using a super-heterodyne architecture or a direct-conversion architecture. In a super-heterodyne architecture, a signal is frequency converted between RF and baseband in multiple stages, e.g., from RF to intermediate frequency (IF) in one stage and then from IF to baseband in another stage. In a direct-conversion architecture, a signal is frequency converted between RF and baseband in one stage. The super-heterodyne architecture and the direct-conversion architecture may use different circuit blocks and / or have different requirements. In the wireless communication device 900 of FIG. 9, the transmitter 908 and receiver 910 are implemented using a direct-conversion architecture.

[0037]

[0047] For the transmit path, a data processor 906 processes data to be transmitted and provides I and Q analog output signals to a transmitter 908. In the example wireless communications device 900, the data processor 906 includes digital-to-analog converters (DACs) 912(1), 912(2) for converting digital signals generated by the data processor 906 to I and Q analog output signals, e.g., I and Q output currents, for further processing.

[0038]

[0048] Within the transmitter 908, lowpass filters 914(1), 914(2) filter the I and Q analog output signals, respectively, to remove undesired signals resulting from previous digital-to-analog conversion. The lowpass filters 914(1), 914(2) may be implemented as an AW filter package 903. Amplifiers (AMPs) 916(1), 916(2) amplify the signals from the lowpass filters 914(1), 914(2), respectively, and provide I and Q baseband signals. An upconverter 918 upconverts the I and Q baseband signals with I and Q transmit (TX) local oscillator (LO) signals from a TX LO signal generator 922 through mixers 920(1), 920(2) to provide an upconverted signal 924. A filter 926 filters the upconverted signal 924 to remove undesired signals caused by frequency upconversion as well as noise in the receive frequency band. A power amplifier (PA) 928 amplifies the upconverted signal 924 from the filter 926 to obtain a desired output power level and provides a transmit RF signal. The transmit RF signal is routed through a duplexer or switch 930 and transmitted via an antenna 932. Either of the low pass filters 914(1) and 914(2) or the filter 926 can be an acoustic wave filter (AW filter) package 903.

[0039]

[0049] In the receive path, an antenna 932 receives a signal transmitted by a base station and provides a receive RF signal, which is routed through a duplexer or switch 930 and provided to a low noise amplifier (LNA) 934. The duplexer or switch 930 is designed to operate at a particular receive (RX)-TX duplexer frequency separation such that the RX signal is separated from the TX signal. The receive RF signal is amplified by the LNA 934 and filtered by a filter 936 to obtain the desired RF input signal. Downconversion mixers 938(1), 938(2) mix the output of the filter 936 with I and Q RX LO signals (i.e., LO_I and LO_Q) from a RX LO signal generator 940 to generate I and Q baseband signals. The I and Q baseband signals are amplified by AMPs 942(1), 942(2) and further filtered by low pass filters 944(1), 944(2) to obtain I and Q analog input signals, which are provided to data processor 906. Both filter 936 and low pass filters 944(1), 944(2) may be AW filter package 903. In this example, data processor 906 includes analog-to-digital converters (ADCs) 946(1), 946(2) to convert the analog input signals to digital signals that are further processed by data processor 906.

[0040]

[0050] In the wireless communication device 900 of FIG. 9, a TX LO signal generator 922 generates I and Q TX LO signals used for frequency up-conversion, and a RX LO signal generator 940 generates I and Q RX LO signals used for frequency down-conversion. Each LO signal is a periodic signal having a particular fundamental frequency. A TX phase-locked loop (PLL) circuit 948 receives timing information from the data processor 906 and generates control signals used to adjust the frequency and / or phase of the TX LO signal from the TX LO signal generator 922. Similarly, a RX PLL circuit 950 receives timing information from the data processor 906 and generates control signals used to adjust the frequency and / or phase of the RX LO signal from the RX LO signal generator 940.

[0041]

[0051] The wireless communication devices 900 may each include a stacked AW filter package 903. The stacked AW filter package 903 includes a first AW filter circuit disposed on a first substrate, a second AW filter circuit disposed on a second substrate, and a metal layer for isolating the first AW filter circuit from the second AW filter circuit to reduce crosstalk, as illustrated in Figures 2A-5 and 8A-8D, and may be provided or integrated in any processor-based device according to any of the aspects disclosed herein. Examples include, but are not limited to, a set-top box, an entertainment unit, a navigation device, a communication device, a fixed location data unit, a mobile location data unit, a global positioning system (GPS) device, a mobile phone, a cellular phone, a smartphone, a session initiation protocol (SIP) phone, a tablet, a phablet, a server, a computer, a portable computer, a mobile computing device, a wearable computing device (e.g., a smart watch, a health or fitness tracker, eyewear, etc.), a desktop computer, a personal digital assistant (PDA), a monitor, a computer monitor, a television, a tuner, a radio, a satellite radio, a music player, a digital music player, a portable music player, a digital video player, a video player, a digital video disc (DVD) player, a portable digital video player, an automobile, a vehicle component, an avionics system, a drone, and a multicopter.

[0042]

[0052] FIG. 10 illustrates an example of a processor-based system 1000 including an RF circuit including a laminated AW filter package 1001. The laminated AW filter package 1001 includes a first AW filter circuit disposed on a first substrate, a second AW filter circuit disposed on a second substrate, and a metal layer that separates the first AW filter circuit from the second AW filter circuit to reduce crosstalk, as illustrated in FIGS. 2A-5 and 8A-8D and according to any aspect disclosed herein. In this example, the processor-based system 1000 includes one or more central processor units (CPUs) 1002, sometimes referred to as CPUs or processor cores, each including one or more processors 1004. The CPUs 1002 may have a cache memory 1006 coupled to the processors 1004 for fast access to temporarily stored data. The CPUs 1002 are coupled to a system bus 1008, which may interconnect master and slave devices included within the processor-based system 1000. As is well known, the CPU 1002 communicates with these other devices by exchanging address, control, and data information via the system bus 1008. For example, the CPU 1002 may communicate bus transaction requests to the memory controller 1010, an example of a slave device. Although not illustrated in Figure 10, multiple system buses 1008 may be provided. Each system bus 1008 constitutes a different fabric.

[0043]

[0053] Other master and slave devices can be connected to the system bus 1008. As illustrated in FIG. 10, these devices can include, by way of example, a memory system 1012 including a memory controller 1010 and one or more memory arrays 1014, one or more input devices 1016, one or more network interface devices 1018, one or more network interface devices 1020, and one or more display controllers 1022. Any of the one or more input devices 1016, the one or more output devices 1018, and the one or more network interface devices 1020 can transmit and / or receive analog signals and can include a laminated AW filter package 1001 to filter such signals. Each of the memory system 1012, the one or more input devices 1016, the one or more output devices 1018, the one or more network interface devices 1020, and the one or more display controllers 1022 can include RF circuitry including the laminated AW filter package 1001. The laminated AW filter package 1001 includes a laminated AW filter package 803. The laminated AW filter package 803 includes a first AW filter circuit disposed on a first substrate, a second AW filter circuit disposed on a second substrate, and a metal layer for isolating the first AW filter circuit from the second AW filter circuit to reduce crosstalk, as illustrated in FIGS. 2A-5 and 8A-8D and according to any of the embodiments disclosed herein. The input device 1016 can include any type of input device, including but not limited to input keys, switches, voice processors, etc. The output device 1018 can include any type of output device, including but not limited to audio, video, other visual indicators, etc. The network interface device 1020 can be any device configured to enable the exchange of data to and from the network 1024.The network 1024 may be any type of network, including, but not limited to, a wired or wireless network, a private or public network, a local area network (LAN), a wireless local area network (WLAN), a wide area network (WAN), a BLUETOOTH™ network, and the Internet. The network interface device 1020 may be configured to support any type of communication protocol desired.

[0044]

[0054] The CPU 1002 may also be configured to access a display controller 1022 via the system bus 1008 to control information sent to one or more displays 1026. The display controller 1022 sends information to be displayed to the display 1026 via one or more video processors 1028, which process the information to be displayed in a format suitable for the display 1026. The display 1026 may include any type of display, including, but not limited to, a cathode ray tube (CRT), a liquid crystal display (LCD), a plasma display, a light-emitting diode (LED) display, and the like. The display controller 1022, the display 1026, and / or the video processor 1028 may include RF circuitry including a laminated AW filter package 1001. The laminated AW filter package 1001 includes a laminated AW filter package 803. The stacked AW filter package 803 includes a first AW filter circuit disposed on a first substrate, a second AW filter circuit disposed on a second substrate, and a metal layer for isolating the first AW filter circuit from the second AW filter circuit to reduce crosstalk, as illustrated in Figures 2A-5 and 8A-8D and in accordance with any of the aspects disclosed herein.

[0045]

[0055] Those skilled in the art will further appreciate that the various illustrative logic blocks, modules, circuits, and algorithms described with respect to the aspects disclosed herein may be implemented as electronic hardware, instructions stored in a memory or another computer-readable medium and executed by a processor or other processing device, or a combination of both. The master and slave devices described herein may be employed in any circuit, hardware component, IC, or IC chip, as examples. The memory disclosed herein may be any type and size of memory and may be configured to store any type of information desired. To clearly illustrate this interchangeability, various illustrative components, blocks, modules, circuits, and steps have been generally described above in terms of their functionality. How such functionality is implemented depends on the particular application, design choices, and / or design constraints imposed on the overall system. Those skilled in the art may implement the described functionality in various ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present disclosure.

[0046]

[0056] The various illustrative logic blocks, modules, and circuits described in connection with the aspects disclosed herein may be implemented or performed using a processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. The processor may be a microprocessor, but alternatively the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration).

[0047]

[0057] Aspects disclosed herein may be embodied in hardware and instructions stored in the hardware and may be embodied in, for example, a Random Access Memory (RAM), a Flash memory, a Read-Only Memory (ROM), an Electrically Programmable ROM (EPROM), an Electrically Erasable Programmable ROM (EEPROM), a register, a hard disk, a removable disk, a CD-ROM, or any other form of computer readable medium known in the art. An exemplary storage medium is coupled to the processor such that the processor can read information from, and write information to, the storage medium. Alternatively, the storage medium may be integral to the processor. The processor and the storage medium may reside in an ASIC. The ASIC may reside in a remote station. Alternatively, the processor and the storage medium may reside as discrete components in a remote station, a base station, or a server.

[0048]

[0058] It should also be noted that the operational steps described in any of the exemplary aspects herein are described to provide examples and discussion. The described operations may be performed in many different sequences other than the illustrated sequence. Furthermore, an operation described in a single operational step may actually be performed in multiple different steps. Additionally, one or more operational steps discussed in the exemplary aspects may be combined. It should be understood that many different modifications may be made to the operational steps illustrated in the flow chart diagrams, as would be readily apparent to one of ordinary skill in the art. One of ordinary skill in the art will also appreciate that information and signals may be represented using a variety of technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referred to throughout the above description may be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, optical fields or optical particles, or any combination thereof.

[0049]

[0059] The previous description of the disclosure is provided to enable any person skilled in the art to make or use the disclosure. Various modifications to the disclosure will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other examples. Thus, the disclosure is not intended to be limited to the examples and designs described herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0050]

[0060] The following numbered clauses describe example implementations. 1. A laminated acoustic wave (AW) filter circuit, comprising: a first substrate having a first AW filter circuit on a first surface thereof; a metal layer on the second surface of the first substrate; a second substrate comprising a second AW filter circuit on a third surface thereof, the second AW filter circuit being disposed in a cavity between a metal layer on the first substrate and the third surface of the second substrate; a metallization layer having at least one metal interconnect disposed on a side of a first substrate, the at least one metal interconnect being coupled to the metal layer and to a second AW filter circuit; 2. The laminated AW filter package of claim 1, wherein at least one metal interconnect is coupled to a ground pad coupled to a second AW filter circuit. 3. The laminated AW filter package of clause 1 or clause 2, further comprising a portion of the metal layer extending on a side of the first substrate between at least one metal interconnect and the side of the first substrate. 4. at least a second metal interconnect disposed on a side of the first substrate; The laminated AW filter package of any one of clauses 1 to 3, further comprising an insulating layer disposed on a side of the first substrate between the side and the at least second metal interconnect, the at least second metal interconnect being electrically insulated from the first substrate. 5. The laminated AW filter package described in any one of clauses 1 to 4, further comprising a frame disposed between the third surface of the second substrate and the metal layer. 6. a cap substrate disposed on the first surface of the first substrate; a second frame disposed between the cap substrate and the first substrate; a contact disposed on the cap substrate; 6. The laminated AW filter package of any one of clauses 1 to 5, wherein at least one metal interconnect is coupled to a contact. 7. A laminated AW filter package as described in any one of clauses 1 to 6, wherein the metal layer comprises a patterned metal layer comprising a metal that is disposed on at least a first portion of the second surface of the first substrate and is not disposed on at least a second portion of the second surface of the first substrate. 8. The laminated AW filter package of claim 2, wherein the ground pad is further coupled to the first AW filter circuit. 9. The metal layer on the second surface of the first substrate is a layer of titanium on the second surface of the first substrate; 9. The laminated AW filter package according to any one of clauses 1 to 8, further comprising: a copper layer on the titanium layer. 10. The laminated AW filter package of any one of clauses 1 to 9 integrated into a device selected from the group consisting of a set-top box, an entertainment unit, a navigation device, a communication device, a fixed location data unit, a mobile location data unit, a global positioning system (GPS) device, a mobile phone, a cellular phone, a smartphone, a session initiation protocol (SIP) phone, a tablet, a phablet, a server, a computer, a portable computer, a mobile computing device, a wearable computing device, a desktop computer, a personal digital assistant (PDA), a monitor, a computer monitor, a television, a tuner, a radio, a satellite radio, a music player, a digital music player, a portable music player, a digital video player, a video player, a digital video disc (DVD) player, a portable digital video player, an automobile, a vehicle component, an avionics system, a drone, and a multicopter. 11. A method for manufacturing a laminated acoustic wave (AW) filter package, comprising: forming a first AW filter circuit on a first surface of a first substrate; forming a metal layer on a second surface of the first substrate; forming a second AW filter circuit on a third surface of a second substrate; forming a cavity around the second AW filter circuit between the metal layer and a third surface of the second substrate; forming a metallization layer comprising at least one metal interconnect on a side of the first substrate, the at least one metal interconnect being coupled to the metal layer and to a second AW filter circuit. 12. The method of claim 11, wherein forming the metallization layer further comprises coupling at least one metal interconnect to a ground pad coupled to the second AW filter circuit. 13. The method of claim 11 or 12, wherein forming a metal layer further comprises forming a metal layer extending on a side of the first substrate between the at least one metal interconnect and the side of the first substrate. 14. The method of any one of clauses 11 to 13, further comprising forming an insulating layer on a side of the first substrate, and forming the metallization layer further comprises forming at least a second metal interconnect on the insulating layer, the second metal interconnect being insulated from the first substrate. 15. The method of any one of clauses 11 to 14, further comprising forming a frame on a third surface of the second substrate. 16. disposing a cap substrate on the first surface of the first substrate; 16. The method of any one of clauses 11-15, further comprising forming a contact on the cap substrate, the contact being coupled to the at least one metal interconnect. 17. The method of any one of clauses 11 to 16, wherein forming the metal layer further comprises disposing a metal layer on at least a first portion of the second surface of the first substrate and patterning the metal layer such that the metal layer is not disposed on at least a second portion of the second surface of the first substrate. 18. The method of any one of clauses 11-17, wherein forming the metallization layer further comprises coupling at least one metal interconnect to the first AW filter circuit on the first substrate. 19. Forming a metal layer on the second surface of the first substrate includes: forming a titanium layer on the second surface and a side surface of the first substrate; 19. The method of any one of claims 11 to 18, further comprising forming a copper layer on the titanium layer. 20. Forming a metal layer on the second surface of the first substrate includes: forming a resist layer on the metal layer; placing a patterned mask over the resist layer; developing the resist layer in exposed areas exposed by the patterned mask; removing the resist layer from the exposed areas; 20. The method of any one of claims 11 to 19, further comprising etching the metal layer from the exposed areas.

Claims

1. 1. A laminated acoustic wave (AW) filter package, comprising: a first substrate having a first AW filter circuit on a first surface thereof; a metal layer on a second surface of the first substrate; a second substrate comprising a second AW filter circuit on a third surface thereof, the second AW filter circuit being disposed in a cavity between the metal layer on the first substrate and the third surface of the second substrate; a metallization layer comprising at least one metal interconnect disposed on a side of the first substrate, the at least one metal interconnect coupled to the metal layer and to the second AW filter circuit; a portion of the metal layer extending on the side of the first substrate between the at least one metal interconnect and the side of the first substrate;

2. The laminated AW filter package of claim 1 , wherein the at least one metal interconnect is coupled to a ground pad coupled to the second AW filter circuit.

3. The laminated AW filter package of claim 1 , further comprising a frame disposed between the third surface of the second substrate and the metal layer.

4. a cap substrate disposed on the first surface of the first substrate; a second frame disposed between the cap substrate and the first substrate; a contact disposed on the cap substrate; The laminated AW filter package of claim 1 , wherein the at least one metal interconnect is coupled to the contact.

5. The laminated AW filter package of claim 2 , wherein the ground pad is further coupled to the first AW filter circuit.

6. The metal layer on the second surface of the first substrate comprises: a titanium layer on the second surface of the first substrate; 10. The laminated AW filter package of claim 1, further comprising: a copper layer on the titanium layer.

7. 7. A device selected from the group consisting of a set-top box, an entertainment unit, a navigation device, a communication device, a fixed location data unit, a mobile location data unit, a global positioning system device, a mobile phone, a cellular phone, a smartphone, a session initiation protocol phone, a tablet, a phablet, a server, a computer, a portable computer, a mobile computing device, a wearable computing device, a desktop computer, a personal digital assistant, a monitor, a computer monitor, a television, a tuner, a radio, a satellite radio, a music player, a digital music player, a portable music player, a digital video player, a video player, a digital video disc player, a portable digital video player, an automobile, a vehicle component, an avionics system, a drone, and a multicopter, wherein the device is integrated with the laminated AW filter package according to any one of claims 1 to 6.

8. 1. A method for manufacturing a laminated acoustic wave (AW) filter package, comprising: forming a first AW filter circuit on a first surface of a first substrate; forming a metal layer on a second surface of the first substrate; forming a second AW filter circuit on a third surface of the second substrate; forming a cavity around the second AW filter circuit between the metal layer and the third surface of the second substrate; forming a metallization layer comprising at least one metal interconnect on a side of the first substrate; and coupling the at least one metal interconnect of the metallization layer to the metal layer and to the second AW filter circuit; The method, wherein forming the metal layer further comprises forming the metal layer extending on the side of the first substrate between the at least one metal interconnect and the side of the first substrate.

9. The method of claim 8 , further comprising coupling the at least one metal interconnect of the metallization layer to a ground pad coupled to the second AW filter circuit.

10. The method of claim 8 , further comprising forming a frame on the third surface of the second substrate.

11. disposing a cap substrate on the first surface of the first substrate; 9. The method of claim 8, further comprising: forming a contact on the cap substrate, the contact coupled to the at least one metal interconnect.

12. 9. The method of claim 8, wherein forming the metal layer further comprises patterning the metal layer to dispose the metal layer on at least a first portion of the second surface of the first substrate and not to dispose the metal layer on at least a second portion of the second surface of the first substrate.

13. The method of claim 8 , wherein forming the metallization layer further comprises coupling the at least one metal interconnect to the first AW filter circuit on the first substrate.

14. forming the metal layer on the second surface of the first substrate includes: forming a titanium layer on the second surface and the side surface of the first substrate; The method of claim 8 further comprising forming a copper layer on the titanium layer.

15. forming the metal layer on the second surface of the first substrate includes: forming a resist layer on the metal layer; placing a patterned mask over the resist layer; developing the resist layer in exposed areas exposed by the patterned mask; removing the resist layer from the exposed areas; The method of claim 8 further comprising: etching the metal layer from the exposed areas.

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