PATENT DOCUMENT

Publication Number: US-9852723-B2
Application Number: US-201414227115-A
Country: US
Kind Code: B2

Title: Acoustic modules

Abstract:
In one embodiment, acoustic devices are formed on a substrate which is then placed on a first HAF layer, a screen, and a second HAF layer. The layers of HAF each have apertures aligned with acoustic ports of the devices. The substrate is heated such that the first layer of HAF adheres to the substrate and the screen and the second layer of HAF adheres to the screen. The substrate is cut to separate the devices into modules. In other embodiments, a waterproof membrane covering the acoustic port of an acoustic module may be bonded to a screen to form a gap such that it moves under pressure until restrained by the screen. In still other embodiments, back volume covers for acoustic devices are formed by stacking and heating a first HAF layer, a glass-reinforced epoxy laminate layer, a second HAF layer, and a top layer on a substrate.

Claims:
We claim: 
     
       1. An acoustic module, comprising:
 an acoustic device including an acoustic port; 
 a screen element bonded to a surface of the acoustic device to cover the acoustic port; and 
 a waterproof membrane bonded to the screen element to cover the acoustic port; 
 wherein a portion of the waterproof membrane aligned with the acoustic port is separated from the screen element by a gap dimensioned to cause the screen element to restrain motion of the portion of the waterproof membrane when pressure sufficient to rupture the waterproof membrane is applied to the waterproof membrane. 
 
     
     
       2. The acoustic module of  claim 1 , wherein the screen element comprises at least one of a stiff material, stainless steel, a composite material, brass, or aluminum. 
     
     
       3. The acoustic module of  claim 1 , wherein the screen element includes a plurality of holes formed by at least one of chemical etching or laser perforation. 
     
     
       4. The acoustic module of  claim 1 , wherein the waterproof membrane comprises polytetrafluoroethylene. 
     
     
       5. The acoustic module of  claim 1 , wherein the waterproof membrane is permeable to air but impermeable to water. 
     
     
       6. The acoustic module of  claim 1 , further comprising:
 a first layer of heat activated film bonding the screen element to the surface of the acoustic device; and 
 a second layer of heat activated film bonding the waterproof membrane to the at least one screen element. 
 
     
     
       7. A portable electronic device, comprising:
 a device housing including a first acoustic port; 
 an acoustic module coupled to the device housing, the acoustic module comprising:
 a second acoustic port aligned with the first acoustic port and extending through a surface of the acoustic module, 
 an acoustic component aligned with the second acoustic port; 
 a waterproof membrane covering the second acoustic port, 
 a screen element covering the second acoustic port and positioned between the waterproof membrane and the acoustic component, 
 and 
 a spacer element disposed between the waterproof membrane and the screen element, the spacer element defining an opening aligned with the second acoustic port, the spacer element creating a gap between the waterproof membrane and screen element sized to allow the waterproof element to vibrate and pass acoustic waves through the first and second acoustic ports, 
 
 wherein a thickness of the spacer element is selected to allow the screen element to restrain movement of the waterproof membrane in the area of the second acoustic port. 
 
     
     
       8. The portable electronic device of  claim 7 , wherein the spacer element comprises a bonding layer joining the waterproof membrane to the screen element. 
     
     
       9. The portable electronic device of  claim 7 , wherein the gap is sized to prevent tearing of the waterproof membrane when water pressure compresses a portion of the waterproof membrane in the area of the second acoustic port against the screen element. 
     
     
       10. An acoustic module, comprising:
 an acoustic port extending through a surface of the acoustic module; 
 an acoustic component aligned with the acoustic port; 
 a waterproof membrane covering the acoustic port; 
 a screen element covering the acoustic port and positioned between the waterproof membrane and the acoustic component; and 
 a spacer element disposed between the waterproof membrane and the screen element, the spacer element having an opening aligned with the acoustic port creating a gap between the waterproof membrane and screen element enabling the waterproof element to vibrate and pass acoustic waves through the acoustic port, 
 wherein a thickness of the spacer element is selected to enable the screen element to restrain movement of the waterproof membrane in the area of the acoustic port. 
 
     
     
       11. The acoustic module of  claim 10 , wherein the spacer element is an adhesive layer bonding the waterproof membrane to the screen element.

Description:
TECHNICAL FIELD 
     This disclosure relates generally to acoustic modules, and more specifically to acoustic modules integrating acoustic mesh and/or wafer manufactured back volume covers. 
     BACKGROUND 
     Many acoustic modules, such as microphone modules or speaker modules, are constructed by forming a plurality of acoustic devices on a substrate which are then die cut to form individual modules. Such individual modules are then typically coupled to a housing with a screen element sandwiched in between (covering an acoustic port of the acoustic module in order to block dust and other solid particles) using pressure sensitive adhesive. However, the pressure necessary to cure such pressure sensitive adhesive typically necessitates the use of a compression boot and a bracket in order to prevent error and/or slippage during the curing. Such assembly may be expensive, may be complex, and may require many parts. 
     Additionally, some acoustic modules may include a waterproof membrane that covers the acoustic port of such modules. Such a waterproof membrane may be permeable to air but not to water and may vibrate such that sound waves are able to enter and/or leave the acoustic module. However, hydrostatic pressure of such a waterproof membrane may stretch the waterproof membrane excessively to the point that the waterproof membrane tears under the hydrostatic pressure. 
     Furthermore, acoustic devices formed in a plurality on a substrate may utilize can elements to form the back volume of such acoustic devices. These can elements may be individually stamped out of metal and/or other materials and may then be separately fixed to the substrate before die cutting. However, such a process of individual stamping and later coupling to substrate may be burdensome and inefficient. 
     SUMMARY 
     The present disclosure details acoustic modules, such as speaker or microphone modules, and methods for manufacturing acoustic modules. In various embodiments, a plurality of acoustic modules that each include an acoustic port may be formed on a substrate. The substrate may be placed on a first layer of heat activated film (such as thermoplastic, thermoset, or other heat activated film) (or “HAF”), a screen layer (such as a mesh, heat resistant acoustic mesh, or other screen element), and a second layer of HAF. The first and second layers of HAF may each have a plurality of apertures that are aligned with the acoustic ports of the acoustic devices. The substrate, layers of HAF, and the screen layer may be heated (which may also include compressing the layers) such that the first layer of HAF adheres to the substrate and the screen layer and the second layer of HAF adheres to the screen layer. The substrate may be cut to separate the plurality of acoustic devices into acoustic device modules. 
     In some cases of such embodiments, individual acoustic device modules may be placed on a housing and heated to cause the second layer of HAF to adhere to the housing. In such cases, the first heating may be performed at a first temperature that causes the second layer of HAF to partially cure and the second heating may be performed at a second temperature that causes the second layer of HAF to fully cure. 
     In various cases, the screen layer may be formed of stainless steel, a composite material, brass, aluminum, and/or similar material. Such a screen layer may be woven and/or may be formed by chemical etching or laser perforating a sheet of material to form a plurality of holes. 
     In one or more embodiments, an acoustic module may include at least one acoustic port. A screen element may be bonded to a surface of the acoustic device to cover the acoustic port. A waterproof (i.e. waterproof and/or water resistant) membrane may be bonded to the at screen element. The waterproof membrane may be bonded to the screen element such that a gap is formed between the screen element and the waterproof membrane over the acoustic port such that the waterproof membrane is able to move through the gap under pressure until restrained by the screen element. 
     In some cases of such embodiments, the waterproof membrane may be formed of polytetrafluoroethylene, expanded polytetrafluoroethylene, and/or similar materials. 
     In one or more embodiments, a plurality of acoustic device components may be placed on a substrate. A first layer of HAF, at least one glass-reinforced epoxy laminate layer, a second layer of HAF, and a top layer may be stacked on the substrate. The first layer of HAF, glass-reinforced epoxy laminate layer, and second layer of HAF may each have a plurality of apertures that accommodate the plurality of acoustic device components such that the first layer of HAF, glass-reinforced epoxy laminate layer, second layer of HAF, and top layer form back volumes for acoustic devices. The substrate, HAF layers, glass-reinforced epoxy laminate layer, and top layer may be heated such that the first layer of HAF adheres to the substrate and the glass-reinforced epoxy laminate layer and the second layer of HAF adheres to the glass-reinforced epoxy laminate layer and the top layer. The substrate may be cut to separate the plurality of acoustic devices into acoustic device modules. 
     In some cases of such embodiments, the glass-reinforced epoxy laminate or similar material layer and/or the top layer may be formed of EMF shielding material and/or the glass-reinforced epoxy laminate or similar material layer and/or the top layer may be coated with an EMF shielding coating. 
     In various implementations, a method for acoustic module manufacture includes: forming a plurality of acoustic devices on a substrate, each of the plurality of acoustic modules including at least one acoustic port; placing the substrate on at least one first layer of heat activated film, at least one screen layer, and at least one second layer of heat activated film wherein the at least one first layer of heat activated film and the at least one second layer of heat activated film each include a plurality of apertures aligned with acoustic ports of the plurality of acoustic device; heating the substrate, the at least one first layer of heat activated film, the at least one screen layer, and the at least one second layer of heat activated film such that the at least one first layer of heat activated film adheres to the substrate and the at least one screen layer and the at least one second layer of heat activated film adheres to the at least one screen layer; and cutting the substrate to separate the plurality of acoustic devices into acoustic device modules. 
     In some implementations, an acoustic module includes an acoustic device with at least one acoustic port; at least one screen element bonded to a surface of the at least one acoustic device to cover the at least one acoustic port; and at least one waterproof membrane bonded to the at least one screen element to cover the at least one acoustic port. At least one gap may be formed between the at least one screen element and the at least one waterproof membrane such that at least a portion of the at least one waterproof membrane is able to move through the gap under pressure until restrained by at least a portion of the at least one screen element. 
     In one or more implementations, a method for acoustic module manufacture includes: placing a plurality of acoustic devices on a substrate; stacking at least one first layer of heat activated film, at least one glass-reinforced epoxy laminate layer, at least one second layer of heat activated film, and a top layer on the substrate wherein the at least one first layer of heat activated film, the at least one glass-reinforced epoxy laminate layer, and the at least one second layer of heat activated film each include a plurality of apertures that accommodate the plurality of acoustic devices to form back volumes for the plurality of acoustic devices; heating the substrate, the at least one first layer of heat activated film, the at least one glass-reinforced epoxy laminate layer, the at least one second layer of heat activated film, and the top layer such that the at least one first layer of heat activated film adheres to the substrate and the at least one glass-reinforced epoxy laminate layer and the at least one second layer of heat activated film adheres to the at least one glass-reinforced epoxy laminate layer and the top layer; and cutting the substrate to separate the plurality of acoustic devices into acoustic device modules. 
     It is to be understood that both the foregoing general description and the following detailed description are for purposes of example and explanation and do not necessarily limit the present disclosure. The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate subject matter of the disclosure. Together, the descriptions and the drawings serve to explain the principles of the disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is an isometric view of a first embodiment of assembly of a plurality of acoustic devices. 
         FIG. 1B  illustrates the plurality of acoustic devices of  FIG. 1A  after assembly. 
         FIG. 1C  illustrates one of the acoustic modules of  FIG. 1B  after die cutting the plurality of acoustic devices into individual modules. 
         FIG. 1D  is a cross-sectional view of the acoustic module of  FIG. 1C  taken along line  1 D of  FIG. 1C . 
         FIG. 1E  is an isometric view of the acoustic module of  FIG. 1C  being coupled to a housing. 
         FIG. 1F  illustrates the view of  FIG. 1E  after coupling. 
         FIG. 2  is a method diagram illustrating a first example method for acoustic module manufacture. This method may involve operations and components similar to those illustrated in  FIGS. 1A-1F . 
         FIG. 3A  is an isometric view of an embodiment of an waterproof acoustic module. 
         FIG. 3B  is a cross-sectional view of the waterproof acoustic module of  FIG. 3A  taken along line  3 B of  FIG. 3A . 
         FIG. 3C  illustrates vibration of the waterproof membrane of the waterproof acoustic module of  FIG. 3B . 
         FIG. 3D  illustrates hydrostatic pressure on the waterproof membrane of the waterproof acoustic module of  FIG. 3B . 
         FIG. 4  is a method diagram illustrating an example method for waterproof acoustic module manufacture. This method may involve components similar to those illustrated in  FIGS. 3A-3D . 
         FIG. 5A  is an isometric view of a second embodiment of assembly of a plurality of acoustic devices. 
         FIG. 5B  illustrates the plurality of acoustic devices of  FIG. 5A  after assembly. 
         FIG. 5C  illustrates one of the acoustic modules of  FIG. 5B  after die cutting the plurality of acoustic devices into individual modules. 
         FIG. 5D  is an isometric view of an alternative implementation of the embodiment of assembly of a plurality of acoustic devices illustrated in  FIG. 5A . 
         FIG. 6  is a method diagram illustrating a second example method for acoustic module manufacture. This method may involve operations and components similar to those illustrated in  FIG. 5A-5C or 5D . 
     
    
    
     DETAILED DESCRIPTION 
     The description that follows includes sample systems, methods, and computer program products that embody various elements of the present disclosure. However, it should be understood that the described disclosure may be practiced in a variety of forms in addition to those described herein. 
     The present disclosure details acoustic modules, such as speaker or microphone modules, and methods for manufacturing acoustic modules. In various embodiments, a plurality of acoustic modules that each include an acoustic port may be formed on a substrate. The substrate may be placed on a first layer of heat activated film (such as thermoplastic, thermoset, or other heat activated film) (or “HAF”), a screen layer (such as a mesh, heat resistant acoustic mesh, or other screen element), and a second layer of HAF. The first and second layers of HAF may each have a plurality of apertures that are aligned with the acoustic ports of the acoustic devices. The substrate, layers of HAF, and the screen layer may be heated (which may also include compressing the layers) such that the first layer of HAF adheres to the substrate and the screen layer and the second layer of HAF adheres to the screen layer. The substrate may be cut to separate the plurality of acoustic devices into acoustic device modules. 
     In one or more embodiments, an acoustic module may include at least one acoustic port. A screen element may be bonded to a surface of the acoustic device to cover the acoustic port. A waterproof (i.e. waterproof and/or water resistant) membrane may be bonded to the at screen element. The waterproof membrane may be bonded to the screen element such that a gap is formed between the screen element and the waterproof membrane over the acoustic port such that the waterproof membrane is able to move through the gap under pressure until restrained by the screen element. 
     In one or more embodiments, a plurality of acoustic device components may be placed on a substrate. A first layer of HAF, at least one glass-reinforced epoxy laminate layer, a second layer of HAF, and a top layer may be stacked on the substrate. The first layer of HAF, glass-reinforced epoxy laminate layer, and second layer of HAF may each have a plurality of apertures that accommodate the plurality of acoustic device components such that the first layer of HAF, glass-reinforced epoxy laminate layer, second layer of HAF, and top layer form back volumes for acoustic devices. The substrate, HAF layers, glass-reinforced epoxy laminate layer, and top layer may be heated such that the first layer of HAF adheres to the substrate and the glass-reinforced epoxy laminate layer and the second layer of HAF adheres to the glass-reinforced epoxy laminate layer and the top layer. The substrate may be cut to separate the plurality of acoustic devices into acoustic device modules. 
       FIG. 1A  is an isometric view of a first embodiment of assembly  100  of a plurality of acoustic devices  101 , such as one or more microphones and/or speakers (such as one or more microelectromechanical systems, or “MEMS” microphones or speakers). As illustrated, a plurality of acoustic devices  101  may be formed on a substrate  102 . The substrate may be placed on at least one first layer of HAF  103  (such as a layer of thermoplastic, thermoset, or other heat activated film), at least one screen layer  104  (such as a mesh, a heat resistant acoustic mesh, or other screen element), and a second layer of HAF  105 . The first and second layers of HAF may have a plurality of apertures  120  and  121  that align with acoustic ports of the acoustic devices (See  FIG. 1D ). 
     In some cases, the screen layer  104  may be formed of stainless steel, a composite material or alloy, brass, aluminum, and/or other such material. The screen layer may include a plurality of holes. Such holes may be formed by weaving, chemical etching of a sheet of material, laser perforation of a sheet of material, and so on. 
     The substrate  102 , layers of HAF  103  and  105 , and the screen layer  104  may be heated. Such heating may cause the first layer of HAF to adhere to the substrate and the screen layer and/or the second layer of HAF to adhere to the screen layer, as shown in  FIG. 1B . Such heating may also involve compressing the substrate, the layers of HAF, and/or the screen layer. 
     The substrate  102  may be cut to separate the plurality of acoustic devices  101  into acoustic device modules. Such cutting may be die cutting. 
       FIG. 1C  illustrates one such acoustic module  106  after cutting the plurality of acoustic devices  101  into individual modules. 
       FIG. 1D  is a cross-sectional view of the acoustic module  106  of  FIG. 1C  taken along line  1 D of  FIG. 1C . By way of example, the acoustic module is illustrated as a MEMS microphone module. However, this is for the purposes of example and the acoustic module may be any kind of acoustic module, such as a speaker module, without departing from the scope of the present disclosure. 
     As illustrated, the acoustic module includes a MEMS microphone component  111  with an acoustic membrane  109  and a front volume  110  positioned over an acoustic port  113 . As further illustrated, the MEMS microphone component is connected to a controller  107  (which may be an application specific integrated circuit) via a connection mechanism  108  (such as a wire bond). The controller may detect vibration of the acoustic membrane caused by sound waves in order to detect sound. Though not shown, the substrate may include one or more vias and/or other connection elements such as contact pads on one or more surfaces for coupling one or more connection mechanisms to the controller. 
       FIG. 1E  is an isometric view of the acoustic module  106  of  FIG. 1C  being coupled to a housing  114  and a connection mechanism  116  (such as one or more surface mount attachment connection mechanisms, hot bar connection mechanisms, anisotropic conductive film connection mechanisms, flex circuit connection mechanisms, and/or other connection mechanisms). The housing may include an acoustic port  115  that aligns with the acoustic port  113  of the acoustic module. 
     The acoustic module  116  may be heated (which may include compression) to couple the acoustic module to the housing.  FIG. 1F  illustrates the view of  FIG. 1E  after coupling. Such heating may cause the second layer of HAF  105  to adhere to the housing  114 . In some cases, the heating performed before cutting the plurality of acoustic devices  101  into individual modules may be performed at a first temperature (such as 180 C) that causes the second layer of HAF  105  to partially cure and the heating of the acoustic module and housing may be performed at a second temperature (such as 240 C) that causes the second layer of HAF  105  to fully cure. 
     As illustrated, the connection mechanism  116  may couple to a surface of the substrate. Such a surface may include one or more contact pads and/or similar mechanisms that electrically connect the connection mechanism to the controller  107 . Although this example is shown as the substrate including such contact pads and/or similar mechanisms on a top surface of the substrate, it is understood that this is an example. In various implementations, such contact pads and/or similar mechanisms may be located on any surface of the substrate. 
     In this way, coupling of the screen element  104  may be part of wafer manufacture of a plurality of acoustic modules as opposed to later being coupled to separated individual acoustic modules. 
     Returning to  FIG. 1E , although the acoustic module  116  is illustrated and described as adhering the second layer of HAF  105  to the housing  114 , it is understood that this is an example. In one or more implementations, other components may be positioned between the second layer of HAF and the housing without departing from the scope of the present disclosure. 
     For example, in some implementations the second layer of HAF  105  may be coupled to a waterproof (i.e., waterproof or water resistant) membrane. The screen layer  104  may prevent dust or other solid particles from entering the acoustic module  106 , but such a waterproof membrane (such as one formed from polytetrafluoroethylene, expanded polytetrafluoroethylene, and/or other such waterproof material) may be permeable to air but impermeable to water. 
     A gap may be formed between the waterproof membrane and the screen layer  104  (such as by the spacing resulting from the coupling of the waterproof membrane and the screen layer  104  by the second layer of HAF) such that the waterproof membrane is able vibrate in order to pass acoustic waves into and/or out of the acoustic module and/or move under hydrostatic pressure. However, the dimensions of the gap may be configured such that the screen layer  104  operates to restrain movement of the waterproof membrane when the waterproof membrane is subjected to sufficient hydrostatic pressure. Such restraint may prevent the waterproof membrane from being stretched far enough by the hydrostatic pressure that it tears. In such implementations, the screen layer  104  may be thick enough to not move under hydrostatic pressures that may otherwise tear the waterproof membrane. 
     In this way, a waterproof membrane that is resistant to hydrostatic pressure may be utilized with acoustic modules. 
     As shown in  FIG. 1A , the acoustic devices  101  may include a back volume cover formed by individual cans. Such cans may be formed by individually stamping the cans from metal and/or other materials. However, it is understood that this is an example. In one or more implementations, other back volume covers for the acoustic devices may be utilized without departing from the scope of the present disclosure. 
     For example, the acoustic devices  101  may be formed by placing a plurality of acoustic components on the substrate  102 . A third layer of HAF, at least one glass-reinforced epoxy or similar material layer, a fourth layer of HAF, and a top layer (such as a top layer formed of plastic, metal, glass-reinforced epoxy, and/or other material) may be stacked on the substrate. The third layer of HAF, one glass-reinforced epoxy or similar material layer, and fourth layer of HAF may each include a plurality of apertures that accommodate the plurality of acoustic device components to form back volumes for the acoustic devices. The substrate, third layer of HAF, glass-reinforced epoxy or similar material layer, fourth layer of HAF, and the top layer may be heated (which may include compressing the third layer of HAF, the glass-reinforced epoxy or similar material layer, and the fourth layer of HAF) such that the third layer of HAF adheres to the substrate and the glass-reinforced epoxy or similar material layer and the fourth layer of HAF adheres to the glass-reinforced epoxy or similar material layer and the top layer. 
     In this way, the back volume cover may be formed as part of wafer manufacture of a plurality of acoustic modules as opposed to individual stamping of can elements. 
       FIG. 2  is a method diagram illustrating a first example method  200  for acoustic module manufacture. This method may involve operations and components similar to those illustrated in  FIGS. 1A-1F . 
     The flow begins at block  201  and proceeds to block  202  where acoustic devices are formed on a substrate. The flow may then proceed to block  203  where the substrate is placed on a first layer of HAF, at least one screen layer, and a second layer of HAF. Next, the flow may proceed to block  204  where the substrate, first layer of HAF, screen layer, and second layer of HAF are heated. Such heating causes the first layer of HAF to adhere to the substrate and the screen layer and the second layer of HAF to adhere to the screen layer. 
     Finally, the flow may proceed to block  205  where the substrate is cut to separate the acoustic devices into individual acoustic modules. Such cutting may be die cutting of the substrate. 
     Although the method  200  is illustrated and described as including a particular set of operations performed in a particular order, it is understood that this is an example. In various implementations, various orders of the same, similar, and/or different operations may be performed without departing from the scope of the present disclosure. 
     For example, block  204  describes heating the substrate, first layer of HAF, screen layer, and second layer of HAF. However, in various implementations such a process may include both heating and compressing the substrate, first layer of HAF, screen layer, and second layer of HAF. 
       FIG. 3A  is an isometric view of an embodiment of an waterproof acoustic module  300 , which may be a speaker module, a microphone module, a MEMS speaker module, a MEMS microphone module, and/or other acoustic module. The acoustic module may include a back volume cover  301  and acoustic components (see components  308 - 312  in  FIG. 3B ) formed on a substrate  302 . A screen layer  304  (such as a mesh, heat resistant acoustic mesh, or other screen element) may be coupled to the substrate to cover an acoustic port (see  313  in  FIG. 3B ) via an adhesive and/or other coupling element layer  303  (which may be HAF and/or other adhesive and/or coupling elements). The screen element may prevent entry of dust or other solid particles into the acoustic module. 
     The acoustic module  300  may also include a waterproof (i.e., waterproof and/or water resistant) membrane  306  (such as one formed from polytetrafluoroethylene, expanded polytetrafluoroethylene, and/or other such waterproof material) coupled to the screen layer  304  by an adhesive and/or other coupling element layer  305  (which may be HAF and/or other adhesive and/or coupling elements). The waterproof membrane be permeable to air but impermeable to water and may cover the acoustic port. The waterproof membrane may vibrate in order to pass acoustic waves into and/or out of the acoustic module  300  and/or move under hydrostatic pressure. 
       FIG. 3B  is a cross-sectional view of the waterproof acoustic module  300  of  FIG. 3A  taken along line  3 B of  FIG. 3A . As illustrated, the acoustic module includes a MEMS microphone component  311  with an acoustic membrane  310  and a front volume  312  positioned over the acoustic port  313 . As further illustrated, the MEMS microphone component is connected to a controller  308  (which may be an application specific integrated circuit) via a connection mechanism  309  (such as a wire bond). Though not shown, the substrate may include one or more vias and/or other connection elements such as contact pads on one or more surfaces for coupling one or more connection mechanisms to the controller. 
     As also illustrated, a gap  330  may be formed between the waterproof membrane  306  and the screen layer  304  (such as by the spacing resulting from the adhesive and/or other coupling element layer  305 ). This may enable the waterproof membrane to vibrate in order to pass acoustic waves  320  and  321  into (as shown in  FIG. 3C ) and/or out of the acoustic module  300  and/or move under hydrostatic pressure. 
     However, the dimensions of the gap may be configured such that the screen layer  304  operates to restrain movement of the waterproof membrane when the waterproof membrane is subjected to sufficient hydrostatic pressure  322  (as illustrated in  FIG. 3D ). Such restraint may prevent the waterproof membrane from being stretched far enough by the hydrostatic pressure that it tears. In such implementations, the screen layer  304  may be thick enough to not move under hydrostatic pressures that may otherwise tear the waterproof membrane. 
     In this way, a waterproof membrane  306  that is resistant to hydrostatic pressure may be utilized with acoustic modules  300 . 
     In some cases, the screen layer  304  may be formed of stainless steel, a composite material or alloy, brass, aluminum, and/or other such material. The screen layer may include a plurality of holes. Such holes may be formed by weaving, chemical etching of a sheet of material, laser perforation of a sheet of material, and so on. 
       FIG. 4  is a method diagram illustrating an example method  400  for waterproof acoustic module manufacture. This method may involve components similar to those illustrated in  FIGS. 3A-3D . 
     The flow begins at block  401  and may then proceed to block  402  where an acoustic device is formed that includes at least one acoustic port. The flow may then proceed to block  403  where a screen element is bonded to a surface of the acoustic device to cover the acoustic port. 
     Next, the flow may then proceed to block  404  where a waterproof membrane is bonded to the screen element to cover the acoustic port. A gap may be formed between the waterproof membrane and the screen element such that the waterproof membrane is able to vibrate to pass sound in and/or out of the acoustic module but the screen element restrains the waterproof membrane when the waterproof membrane is subjected to hydrostatic pressure. 
     Although the method  400  is illustrated and described as including a particular set of operations performed in a particular order, it is understood that this is an example. In various implementations, various orders of the same, similar, and/or different operations may be performed without departing from the scope of the present disclosure. 
     For example, blocks  403  and  404  are illustrated as separate operations performed in a linear order. However, in various implementations these operations may be performed simultaneously. 
       FIG. 5A  is an isometric view of a second embodiment of assembly  500  of a plurality of acoustic devices. As illustrated, a plurality of acoustic components  501 - 503  may be formed on a substrate  504 . The acoustic components may be components of speaker module, a microphone module, a MEMS speaker module, a MEMS microphone module, and/or other acoustic module. 
     As also illustrated, a first layer of HAF  505 , at least one glass-reinforced epoxy or similar material layer  507 , a fourth layer of HAF  509 , and a top layer  511  (such as a top layer formed of plastic, metal, glass-reinforced epoxy, and/or other material) may be stacked on the substrate  502 . The first layer of HAF, one glass-reinforced epoxy or similar material layer, and second layer of HAF may each include a plurality of apertures  506 ,  508 , and  510  that accommodate the plurality of acoustic device components to form back volumes for the acoustic devices. 
     The substrate  504 , first layer of HAF  505 , glass-reinforced epoxy or similar material layer  507 , second layer of HAF  509 , and the top layer  511  may be heated (which may include compressing the second layer of HAF, the glass-reinforced epoxy or similar material layer, and the second layer of HAF) such that the first layer of HAF adheres to the substrate and the glass-reinforced epoxy or similar material layer and the second layer of HAF adheres to the glass-reinforced epoxy or similar material layer and the top layer. 
       FIG. 5B  illustrates the plurality of acoustic devices of  FIG. 5A  after assembly  500 . The substrate may be cut, such as by die cutting, to separate the plurality of acoustic devices into acoustic device modules.  FIG. 5C  illustrates one of the acoustic modules of  FIG. 5B  after die cutting the plurality of acoustic modules into individual modules. 
     In this way, the back volume cover may be formed as part of wafer manufacture of a plurality of acoustic modules as opposed to individual stamping of can elements. 
       FIG. 5D  is an isometric view of an alternative implementation of the embodiment of assembly  500  of a plurality of acoustic modules illustrated in  FIG. 5A . In this embodiment, the glass-reinforced epoxy or similar material layer  507  may be coated with an electromagnetic frequency (or “EMF”) shielding coating  521  and/or the top layer  511  may be coated with an EMF shielding coating  520 . 
     Alternatively, the top layer  511  and/or the glass-reinforced epoxy or similar material layer  507  may be formed of an EMF shielding material and not include such a coating  520  and/or  521 . Additionally, in some embodiments, the glass-reinforced epoxy or similar material layer and/or the top layer may instead be covered with an EMF shield element. 
       FIG. 6  is a method diagram illustrating a second example method  600  for acoustic module manufacture. This method may involve operations and components similar to those illustrated in  FIG. 5A-5C or 5D . 
     The flow begins at block  601  and may then proceed to block  602  where a plurality of acoustic device components are placed on a substrate. The flow may then proceed to block  603  where a first layer of HAF, a glass-reinforced epoxy laminate or similar material layer, a second HAF layer, and a top layer are stacked on the substrate. The first layer of HAF, glass-reinforced epoxy laminate or similar material layer, and second HAF layer may each include apertures accommodating the acoustic device components and form back volume covers for acoustic devices that include the components. 
     Next, the flow may proceed to block  604  where the substrate, first layer of HAF, glass-reinforced epoxy laminate or similar material layer, the second layer of HAF, and the top layer are heated. Such heating may also include compressing these layers and may cause the first layer of HAF to adhere to the substrate and the glass-reinforced epoxy laminate or similar material layer and the second layer of HAF to adhere to the glass-reinforced epoxy laminate or similar material layer and the top layer. 
     Finally, the flow may proceed to block  605  where the substrate is cut to separate the acoustic devices into individual acoustic modules. Such cutting may include die cutting. 
     Although the method  600  is illustrated and described as including a particular set of operations performed in a particular order, it is understood that this is an example. In various implementations, various orders of the same, similar, and/or different operations may be performed without departing from the scope of the present disclosure. 
     For example, in some implementations the method  600  may also include adding EMF shielding, such as forming the glass-reinforced epoxy laminate or similar material layer and/or the top layer from an EMF shielding material and/or coating the glass-reinforced epoxy laminate or similar material layer and/or the top layer with an EMF shielding coating. 
     As described above and illustrated in the accompanying figures, the present disclosure details acoustic modules, such as speaker or microphone modules, and methods for manufacturing acoustic modules. In various embodiments, a plurality of acoustic modules that each include an acoustic port may be formed on a substrate. The substrate may be placed on a first layer of heat activated film (such as thermoplastic, thermoset, or other heat activated film) (HAF), a screen layer (such as a mesh, heat resistant acoustic mesh, or other screen element), and a second layer of HAF. The first and second layers of HAF may each have a plurality of apertures that are aligned with the acoustic ports of the acoustic devices. The substrate, layers of HAF, and the screen layer may be heated (which may also include compressing the layers) such that the first layer of HAF adheres to the substrate and the screen layer and the second layer of HAF adheres to the screen layer. The substrate may be cut to separate the plurality of acoustic devices into acoustic device modules. 
     In one or more embodiments, an acoustic module may include at least one acoustic port. A screen element may be bonded to a surface of the acoustic device to cover the acoustic port. A waterproof (i.e. waterproof and/or water resistant) membrane may be bonded to the at screen element. The waterproof membrane may be bonded to the screen element such that a gap is formed between the screen element and the waterproof membrane over the acoustic port such that the waterproof membrane is able to move through the gap under pressure until restrained by the screen element. 
     In one or more embodiments, a plurality of acoustic devices may be placed on a substrate. A first layer of HAF, at least one glass-reinforced epoxy laminate layer, a second layer of HAF, and a top layer may be stacked on the substrate. The first layer of HAF, glass-reinforced epoxy laminate layer, and second layer of HAF may each have a plurality of apertures that accommodate the plurality of acoustic devices such that the first layer of HAF, glass-reinforced epoxy laminate layer, second layer of HAF, and top layer form back volumes for the acoustic devices. The substrate, HAF layers, glass-reinforced epoxy laminate layer, and top layer may be heated such that the first layer of HAF adheres to the substrate and the glass-reinforced epoxy laminate layer and the second layer of HAF adheres to the glass-reinforced epoxy laminate layer and the top layer. The substrate may be cut to separate the plurality of acoustic devices into acoustic device modules. 
     In the present disclosure, the methods disclosed may be implemented as sets of instructions or software readable by a device. Further, it is understood that the specific order or hierarchy of steps in the methods disclosed are examples of sample approaches. In other embodiments, the specific order or hierarchy of steps in the method can be rearranged while remaining within the disclosed subject matter. The accompanying method claims present elements of the various steps in a sample order, and are not necessarily meant to be limited to the specific order or hierarchy presented. 
     The described disclosure may be provided as a computer program product, or software, that may include a non-transitory machine-readable medium having stored thereon instructions, which may be used to program a computer system (or other electronic devices) to perform a process according to the present disclosure. A non-transitory machine-readable medium includes any mechanism for storing information in a form (e.g., software, processing application) readable by a machine (e.g., a computer). The non-transitory machine-readable medium may take the form of, but is not limited to, a magnetic storage medium (e.g., floppy diskette, video cassette, and so on); optical storage medium (e.g., CD-ROM); magneto-optical storage medium; read only memory (ROM); random access memory (RAM); erasable programmable memory (e.g., EPROM and EEPROM); flash memory; and so on. 
     It is believed that the present disclosure and many of its attendant advantages will be understood by the foregoing description, and it will be apparent that various changes may be made in the form, construction and arrangement of the components without departing from the disclosed subject matter or without sacrificing all of its material advantages. The form described is merely explanatory, and it is the intention of the following claims to encompass and include such changes. 
     While the present disclosure has been described with reference to various embodiments, it will be understood that these embodiments are illustrative and that the scope of the disclosure is not limited to them. Many variations, modifications, additions, and improvements are possible. More generally, embodiments in accordance with the present disclosure have been described in the context or particular embodiments. Functionality may be separated or combined in blocks differently in various embodiments of the disclosure or described with different terminology. These and other variations, modifications, additions, and improvements may fall within the scope of the disclosure as defined in the claims that follow.

Metadata:
Filing Date: 20140327
Publication Date: 20171226
Grant Date: 20171226
Priority Date: 20140327
Inventors: ELY COLIN M.
ROTHKOPF FLETCHER R.
Assignee: APPLE INC
CPC Classifications: [{"code": "H04R19/005", "inventive": true, "first": false, "tree": "[]"}, {"code": "G10K9/22", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04R31/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "G10K9/22", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04R19/005", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04R31/00", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 54188999