PATENT DOCUMENT

Publication Number: US-9768225-B2
Application Number: US-201615232532-A
Country: US
Kind Code: B2

Title: Overmolded reconstructed camera module

Abstract:
A camera module including a die having a top side and a bottom side, an image sensor is positioned on the top side of the die and a conductive via is formed through the die to provide an electrical connection between the top side and the bottom side; an overmold casing formed around the die; and a lens holder assembly attached to the top side of the die and the overmold casing. A method of producing a camera module including providing an image sensor die that is overmolded within a casing, the image sensor die having a top side and a bottom side, wherein an image sensor is positioned on the top side and a conductive via is formed through the image sensor die from the top side to the bottom side; and attaching a lens holder to the top side of the image sensor die.

Claims:
What is claimed is: 
     
       1. A camera module comprising:
 a microelectronic die positioned within a first casing, the microelectronic die having a top side and a bottom side, an image sensor is positioned on the top side of the microelectronic die, and a conductive via is formed through the microelectronic die to provide an electrical connection between the top side and the bottom side; 
 an electronic device positioned within a second casing formed on a top side of the first casing; and 
 a lens holder assembly positioned over the top side of the microelectronic die and coupled to the second casing. 
 
     
     
       2. The camera module of  claim 1  further comprising:
 a transparent member positioned over the image sensor, the transparent member being attached directly to the top side of the microelectronic die and surrounded by the second casing. 
 
     
     
       3. The camera module of  claim 1  further comprising:
 a metal layer, wherein the metal layer is (a) on one of the top side or the bottom side of the microelectronic die and (b) extends from the via and over the first casing to redistribute the electrical connection to a location outside of the microelectronic die. 
 
     
     
       4. The camera module of  claim 1  wherein the first casing and the second casing are overmolded to the microelectronic die and the electronic device, respectively. 
     
     
       5. The camera module of  claim 1  where the electronic device is a passive surface-mount device. 
     
     
       6. The camera module of  claim 1  wherein the electronic device is electrically connected to the conductive via by a redistribution layer encased between the first casing and the second casing. 
     
     
       7. The camera module of  claim 2  wherein the first casing is molded directly to, and contacts, the top side of the microelectronic die and portions of the transparent member. 
     
     
       8. The camera module of  claim 1  wherein the first casing or the second casing is made of a polymer, an elastomer, a glass, or a thermoplastic material. 
     
     
       9. A method of producing a camera module, the method comprising:
 providing a carrier having an adhesive tape layer; 
 attaching a microelectronic die to the adhesive tape layer, the microelectronic die having a first side with an image sensor formed thereon and a second side, and wherein a conductive via is formed between the first side and the second side, the adhesive tape layer being attached to the second side; 
 forming a first casing around the microelectronic die; 
 positioning a surface-mount device over the first side of the microelectronic die and the first casing; 
 attaching a transparent member to the first side of the microelectronic die, the transparent member being positioned over the image sensor such that the image sensor is enclosed between the microelectronic die and the transparent member; and 
 forming a second casing over the first casing and around the surface-mount device. 
 
     
     
       10. The method of  claim 9  further comprising:
 positioning a lens holder assembly over the transparent member and the second casing to form an overmolded camera module; and 
 removing the carrier having the adhesive tape layer such that the second side of the microelectronic die is exposed. 
 
     
     
       11. The method of  claim 9  wherein the first casing is formed by a molding process comprising:
 positioning a mold cope over the microelectronic die and the transparent member; and 
 injecting mold material between the mold cope and the carrier to form the first casing. 
 
     
     
       12. The method of  claim 9  further comprising:
 prior to attaching a lens holder assembly, removing the adhesive tape layer and carrier to expose the second side of the microelectronic die; and 
 forming a redistribution layer between the via and the first casing. 
 
     
     
       13. The method of  claim 9  wherein the first casing and the second casing are formed by a molding process comprising:
 molding a first mold material around the microelectronic die to form the first casing around the microelectronic die; 
 forming a redistribution layer between an end of the via at the first side of the microelectronic die and the first casing; 
 positioning the surface-mount device over the first side of the microelectronic die and the first casing such that it is electrically connected to the redistribution layer; and 
 molding a second mold material around the surface-mount device to form the second casing, wherein the surface-mount device and redistribution layer are encased within the first casing and the second casing. 
 
     
     
       14. A method of producing a camera module, the method comprising:
 providing an image sensor die that is positioned within a first casing and an electronic device positioned within a second casing positioned on the first casing, the image sensor die having a top side and a bottom side, wherein an image sensor and a transparent member are positioned on the top side and a conductive via is formed through the image sensor die from the top side to the bottom side; and 
 mounting a lens holder assembly to the second casing and over the top side of the image sensor die. 
 
     
     
       15. The method of  claim 14  wherein an injection molding process is used to form the first casing and the second casing. 
     
     
       16. The method of  claim 15  wherein the injection molding process comprises:
 injection molding the first casing around the image sensor die; 
 forming a redistribution layer on the top side of the image sensor die and the first casing; 
 mounting the electronic device over the redistribution layer and the first casing; and 
 injection molding the second casing over the electronic device and the first casing. 
 
     
     
       17. The method of  claim 14  further comprising:
 forming a redistribution layer between the via and on the first casing. 
 
     
     
       18. The method of  claim 17  wherein the redistribution layer is formed on the top side of the die and a top side of the first casing such that it is between the first casing and the second casing. 
     
     
       19. The method of  claim 17  wherein the redistribution layer is formed on the bottom side of the die.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The application is a continuation of co-pending U.S. patent application Ser. No. 14/611,950, filed Feb. 2, 2015 and incorporated herein by reference. 
    
    
     FIELD 
     Embodiments related to an overmolded camera module are disclosed. More particularly, an embodiment related to an overmolded camera module and lens assembly is disclosed. 
     BACKGROUND 
     Camera modules have been incorporated into a variety of consumer electronics devices, including smart phones, mobile audio players, personal digital assistants, and both portable and desktop computers. A typical camera module includes an optical system used to collect and transmit light from an imaged scene to an image sensor. The optical system generally includes at least one lens associated with one aperture. The lens collects and transmits light to the image sensor. The aperture limits the light collected and transmitted by the lens, and is therefore termed the stop aperture, or alternatively, the entrance pupil aperture. The image sensor may be part of, or mounted to, a microelectronic or integrated circuit die, which is surrounded by a ceramic substrate. The ceramic substrate may include interconnects for providing electrical connections between the die and other components (e.g. a flex circuit). A cover glass to protect the image sensor may further be mounted to the ceramic substrate, over the image sensor. 
     Each of these components, however, are typically singulated elements that require a long assembly process and complex handling procedures. For example, in some cases, assembly includes positioning one or more image sensor dies (positioned within the ceramic substrate) within a carrier boat. The carrier boat may include a top layer and bottom layer and openings within which the image sensor dies are aligned and then sandwiched between the top and bottom layers so that they remain stationary during the remaining assembly steps (e.g. flip chip bonding, under fill, glass attach, etc). Properly positioning the sensor dies within the carrier boat openings and subsequent assembly steps can be very difficult and time consuming. In addition, the use of a ceramic substrate around each of the image sensor dies to provide electrical connections to and from the die can undesirably increase the overall x, y and z dimensions of the camera module because, for example, space must be provided between the die and the substrate to accommodate electrical connections (e.g. solder bumps) and underfill mounting materials (e.g. a glue) used to mount the substrate to the die. 
     SUMMARY 
     An overmolded camera module, particularly for use in portable consumer electronics device applications, is disclosed. In one embodiment, the overmolded camera module includes a microelectronic or integrated circuit die having a top side and a bottom side. An image sensor is positioned on the top side of the die and a conductive via is formed through the die to provide an electrical connection between the top side and the bottom side. A transparent member, such as a transparent window, may further be formed over the image sensor. An overmold casing is formed around the die and the transparent member, to produce an overmolded image sensing device which is relatively compact. A lens holder assembly is further attached to the top side of the die (i.e. side having the image sensor), over the transparent member and the overmold casing, to complete the camera module. In some embodiments, a conductive layer (e.g. a redistribution layer) may be formed from the via and over the casing to redistribute an electrical connection outside of the die. In addition, in still further embodiments, an electronic device such as a surface-mount device (SMD) may be embedded within the casing along with the die and additional conductive layers may be formed from the via to the SMD. 
     In an embodiment, a method of producing a camera module assembly is provided. The method includes overmolding an image sensor die to an adhesive carrier, for example, an adhesive layer or platform. The adhesive carrier or platform may serve as the die carrier during subsequent processing operations such that a separate carrier such as a carrier boat, as is commonly used, may be omitted. In addition, the image sensor die may include one or more conductive vias which are connected to one or more metallic layers (e.g. redistribution layers) which are formed on or within the overmold casing. In this aspect, the positioning of a ceramic substrate around the die to provide electrical connections is not necessary. The omission of the ceramic substrate may in turn decrease the x, y and z dimensions of the overall structure, in comparison to a structure in which the die is positioned within a ceramic substrate. More specifically, the method may include providing a carrier having an adhesive tape layer and attaching a die to the adhesive tape layer. The carrier may be, for example, a wafer or the like. The die may include a top side with an image sensor, for example an image sensor array, formed thereon and a bottom side. The conductive via(s) may be formed between the top side and the bottom side. The adhesive tape layer may be attached to the bottom side (i.e. the side opposite the image sensor). A transparent member may be positioned over the image sensor and attached to the top side of the die such that the image sensor is enclosed between the die and the transparent member. A mold material may be molded around exposed surfaces of the die and transparent member to form a casing around the die. Once the die is encased within the casing, a lens holder assembly may be positioned over the transparent member and the casing to form a molded camera module. A metal layer such as a redistribution layer may further be formed from one of the conductive vias to the casing to redistribute an electrical connection outside of the die. In addition, an electronic device (e.g. a surface-mount device) could be molded within a second molded casing formed over the first casing. 
     In another embodiment, the method may include providing an image sensor die that is overmolded within a mold material. The image sensor die may have an image sensor and a transparent member positioned on a top side and a conductive via formed through the image sensor die from the top side to the bottom side. A lens holder may further be attached to the top side of the overmolded image sensor die to form the camera module. 
     The above summary does not include an exhaustive list of all aspects of the present invention. It is contemplated that the invention includes all systems and methods that can be practiced from all suitable combinations of the various aspects summarized above, as well as those disclosed in the Detailed Description below and particularly pointed out in the claims filed with the application. Such combinations have particular advantages not specifically recited in the above summary. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The embodiments are illustrated by way of example and not by way of limitation in the figures of the accompanying drawings in which like references indicate similar elements. It should be noted that references to “an” or “one” embodiment in this disclosure are not necessarily to the same embodiment, and they mean at least one. 
         FIG. 1  is a cross-sectional side view of one embodiment of a camera module. 
         FIG. 2  is a cross-sectional side view of another embodiment of a camera module. 
         FIG. 3  is a flowchart of a process for producing a camera module in accordance with one embodiment. 
         FIG. 4  is a pictorial view illustrating an operation for forming a camera module in accordance with one embodiment. 
         FIG. 5  is a pictorial view illustrating an operation for forming a camera module in accordance with one embodiment. 
         FIG. 6  is a pictorial view illustrating an operation for forming a camera module in accordance with one embodiment. 
         FIG. 7  is a pictorial view illustrating an operation for forming a camera module in accordance with one embodiment. 
         FIG. 8  is a pictorial view illustrating an operation for forming a camera module in accordance with one embodiment. 
         FIG. 9  is a pictorial view illustrating an operation for forming a camera module in accordance with one embodiment. 
         FIG. 10  is a pictorial view illustrating an operation for forming a camera module in accordance with one embodiment. 
         FIG. 11  is a pictorial view illustrating an operation for forming a camera module in accordance with one embodiment. 
         FIG. 12  is a pictorial view illustrating an operation for forming a camera module in accordance with one embodiment. 
         FIG. 13  is a pictorial view illustrating an operation for forming a camera module in accordance with one embodiment. 
         FIG. 14  is a pictorial view illustrating an operation for forming a camera module in accordance with one embodiment. 
         FIG. 15  is a flowchart of a method of producing a camera module in accordance with another embodiment. 
         FIG. 16  illustrates one embodiment of a simplified schematic view of one embodiment of an electronic device in which a camera module may be implemented. 
         FIG. 17  illustrates a block diagram of some of the constituent components of an embodiment of an electronic device in which an embodiment of the invention may be implemented. 
     
    
    
     DETAILED DESCRIPTION 
     Embodiments describe camera module assemblies, particularly for use in portable consumer electronics device applications. However, while some embodiments are described with specific regard to integration within mobile electronics devices, the embodiments are not so limited and certain embodiments may also be applicable to other uses. For example, a camera module as disclosed herein may be incorporated into an electronic device that remains at a fixed location, or is used in relatively stationary applications, e.g., as a lens in a multimedia disc player or desk top device having a display, for example, a computer. 
     In various embodiments, description is made with reference to the figures. However, certain embodiments may be practiced without one or more of these specific details, or in combination with other known methods and configurations. In the following description, numerous specific details are set forth, such as specific configurations, dimensions, and processes, in order to provide a thorough understanding of the embodiments. In other instances, well-known processes and manufacturing techniques have not been described in particular detail in order to not unnecessarily obscure the description. Reference throughout this specification to “one embodiment,” “an embodiment”, or the like, means that a particular feature, structure, configuration, or characteristic described is included in at least one embodiment. Thus, the appearance of the phrase “one embodiment,” “an embodiment,” or the like, in various places throughout this specification are not necessarily referring to the same embodiment. Furthermore, the particular features, structures, configurations, or characteristics may be combined in any suitable manner in one or more embodiments. 
     The use of relative terms throughout the description, such as “top” and “bottom” may denote a relative position or direction. For example, a “top edge”, “top end” or “top side” may be directed in a first axial direction and a “bottom edge”, “bottom end” or “bottom side” may be directed in a second direction opposite to the first axial direction. However, such terms are not intended to limit the use of the camera module disclosed herein to a specific configuration described in the various embodiments below. For example, a top side of a camera module or its components (e.g. a die or image sensor) may be directed in any direction with respect to an external environment. 
     Referring to  FIG. 1 ,  FIG. 1  is a cross-sectional side view of one embodiment of a camera module. Camera module  100  may include an image sensor device  102  and a lens assembly  104  attached to the image sensor device  102 . The image sensor device  102  may include a die  106 . Die  106  may be, for example, a block of semiconducting material on, or within which, a functional circuit is fabricated. Die  106  therefore may also be referred to herein as a microelectronic die or an integrated circuit die. Die  106  may have an image sensor  108  positioned along one side such that die  106  may be considered an image sensor die and include suitable imaging circuitry. In the illustrated embodiment, die  106  includes a top side  110  (i.e. first side) and a bottom side  112  (second side) and image sensor  108  is positioned along top side  110 . The terms “top side” and “bottom side” are used herein to refer to different sides of die  106 , but do not necessarily refer to any particular die orientation. In other words, the “top side” of die  106  may be a side of die  106  facing one axial direction while the “bottom side” faces an opposite axial direction. Moreover, although image sensor  108  is described as being positioned along top side  110  of die  106 , image sensor  108  could be positioned along bottom side  112  or both sides of die  106 . 
     Die  106  may further include one or more vias  114  formed through die  106 , between the top side  110  and the bottom side  112 . In the view illustrated in  FIG. 1 , die  106  includes at least two vias  114 . Vias  114  may be conductive (e.g. include a conductive material) such that they allow for electrical connections to run through die  106 , and between electronic devices or components that may be mounted to the top side  110  and/ or bottom side  112  of die  106 . In this aspect, vias  114  may be referred to as conductive vias, or more specifically, through-silicon vias (TSV) in cases where die  106  is made of silicon. Contact pads  116  may further be provided at one or more of the ends of vias  114 , in this case, the ends of vias  114  exposed through the top side  110  of die  106 , to facilitate an electrical connection to a nearby device or component. 
     In one embodiment, a conductive layer  118 , for example, a redistribution layer formed of a metal material, may extend from each of vias  114  outside of die  106  to redistribute an electrical connection outside of die  106  (e.g. to a device mounted near die  106 ). In the illustrated embodiment, conductive layers  118  are formed on the bottom side  112  of die  106  (i.e. a side of die  106  opposite image sensor  108 ). Since die  106  includes conductive vias  114  and conductive layers  118  electrically connected to each of the vias  114 , a ceramic substrate, which would typically be used to provide electrical connections between the die and other components outside of the die, can be omitted. 
     Die  106  may further include a transparent member  120  positioned over image sensor  108 . Transparent member  120  may help to protect image sensor  108  during the assembly process. Representatively, in one embodiment, transparent member  120  is a transparent glass or polymer window mounted directly to the top side  110  of die  106 . For example, transparent member  120  may be mounted using a mounting material which forms mounting members  122 , which also act as spacers to space transparent member  120  a distance from image sensor  108 . In some embodiments, the mounting material may be an epoxy resin or other mounting material suitable for directly attaching transparent member  120  to die  106 . 
     As previously discussed, die  106  does not need to be mounted within a ceramic substrate therefore transparent member  120  can be directly attached to the top side  110  of die  106 , instead of a portion of a ceramic substrate positioned over the die, thereby reducing a z-height of image sensor device  102 . With the ceramic substrate omitted, die  106  (including transparent member  120 ) can be encased within a casing  124  that conforms to the dimensions of die  106 . In other words, casing  124  is formed directly on, and in contact with, surfaces of die  106 . Representatively, casing  124  may be formed by a molding material such that casing  124  conforms to the size and shape of die  106  and transparent member  120 . The molding material may be, for example, a polymer, an elastomer, a glass, or a thermoplastic. For example, the molding material may be a polymer such as an epoxy resin which cures to form an epoxy casing  124 . It is noted that casing  124  should surround and contact all exposed sides of both die  106  and transparent member  120 , and also overlap outer portions of the top surface  110  of die  106 , but not overlap the top surface of transparent member  120  so that light can be transmitted through transparent member  120  to image sensor  108 . 
     Representatively, casing  124  may be formed by an overmolding or injection molding process in which die  106  having transparent member  120  attached thereto is enclosed within a mold cope and a mold material is injected around die  106  and transparent member  120 . Forming of casing  124  as an overmolded structure around die  106  and transparent member  120  helps to reduce x, y and/or z dimensions of image sensor device  102  in several ways. Said another way, casing  124  helps to reduce a width, length, and/or height dimension of image sensor device  102 . For example, because casing  124  is molded directly to exposed surfaces of die  106  and transparent member  120 , gaps around die  106  which may unnecessarily increase the x, y and/or z dimensions of image device assembly  102 , and in turn, camera module  100 , can be eliminated. For example, an x (width), z (height) and in some cases y (length) dimension of the image sensor device  102  may be from  100  microns to  200  microns less than those found in a device that is mounted within a ceramic substrate type carrier. In addition, since a ceramic substrate around die  106  is no longer necessary, transparent member  120  can be directly attached to die  106 , and in turn encased within casing  124 , thereby reducing a z-height dimension of image sensor device  102 . Still further, an overlap between casing  124  and the top side  110  of die  106  can be controlled, and in some cases reduced below that which is seen when a ceramic substrate is used, which in turn may allow for an increase in a surface area of image sensor  108 . 
     Once the image sensor device  102  is complete, i.e. die  106  and transparent member  120  are encased within casing  124 , lens assembly  104  is attached to image sensor device  102  to complete the camera module. Representatively, lens assembly  104  may be positioned over image sensor  108  and mounted to casing  124 . Lens assembly  104  may be any type of lens assembly suitable for implementation within a camera module. For example, in one embodiment, lens assembly  104  may include a lens stack  126  mounted within a support structure  128  (e.g. a barrel). The lens stack  126  may, for example, include two lenses  130 ,  132  aligned along an optical axis between external window  134  and image sensor  108 , which facilitate transmission and/ or focusing of light rays on image sensor  108 . Although not illustrated, lens assembly  104  may include numerous lenses, filters, and other optical components aligned along an optical axis to achieve various optical functionalities. External window  134  may, for example, be a transparent glass or polymer window located substantially coplanar with a mobile device housing. 
     It should further be understood that, although not shown, other components such as flexible circuit boards, voice coil motors, filters, covers, support members, etc. may be connected to camera module  100  to support the various camera operations. In addition, although lens assembly  104  is shown attached to casing  124 , it is contemplated that in some embodiments lens assembly  104  may be omitted. For example, in an embodiment where image sensor device  102  does not require an assembly of lenses for imaging, lens assembly  104  is omitted. 
       FIG. 2  is a cross-sectional side view of another embodiment of a camera module. Camera module  200  is substantially similar to camera module  100  described in reference to  FIG. 1  except that in this embodiment, one or more electronic devices  240  are encased or overmolded within casing  224 . 
     Representatively, similar to camera module  100 , camera module  200  may include an image sensor device  202  and a lens assembly  204  attached to the image sensor device  202 . The image sensor device  202  may include a die  206  having an image sensor  208  positioned along one side such that die  206  may be considered an image sensor die. In the illustrated embodiment, die  206  includes a top side  210  and a bottom side  212  and image sensor  208  is positioned along top side  210 , although image sensor  208  may be positioned along bottom side  212  or both sides of die  206 . Die  206  may further include one or more conductive vias  214  formed through die  206 , between the top side  210  and the bottom side  212 , contact pads  216  and conductive layers  218  as previously discussed in reference to  FIG. 1 . 
     Die  206  may further include a transparent member  220  positioned over image sensor  108  to, for example, protect image sensor  208  during the assembly process. Representatively, in one embodiment, transparent member  220  is a glass window mounted directly to the top side  210  of die  206 . For example, transparent member  220  may be mounted using a mounting material which forms mounting members  222 , which also act as spacers to space transparent member  220  a distance from image sensor  208 , as previously discussed in reference to  FIG. 1 . It should be noted that because transparent member  220  is directly attached to the top side  210  of die  206 , as opposed to a ceramic substrate within which die  206  is mounted (as may be the case with other systems), a z-height of image sensor device  202  may be reduced. 
     Image sensor device  202  may further include one or more of electronic devices  240  mounted to die  206 . Electronic devices  240  may be, for example, a passive, active or electromechanical device mounted to top side  210  of die  206 , in other words a surface-mount device (SMD). To facilitate an electrical connection with electronic devices  240 , additional conductive layers  242  (i.e. redistribution layers) may be formed between pads  216  and electronic devices  240 . Representatively, where electronic devices  240  are mounted to the top side  210  of die  206 , conductive layers  242  may extend from pads  216  at the top side  210  of die  206  to a location outside of die  206 . 
     Casing  224  may be formed around each of the previously discussed components (e.g. die  206 , transparent member  220  and the associated electronic devices  240 ) using a molding process such that casing  224  conforms to the size and shape of die  206  and transparent member  220 . Representatively, casing  224  may be formed by one or more overmolding or injection molding processes as discussed in reference to  FIG. 1  such that an overmolded image sensor device  202  having a reduced x, y and/or z dimension is formed. 
     Once the image sensor device  202  is complete, i.e. die  206 , transparent member  220  and electronic devices  240  are encased within casing  224 , lens assembly  204  is attached to image sensor device  202 . Representatively, lens assembly  204  may be positioned over image sensor  208  and mounted to casing  224 . Lens assembly  204  may be any type of lens assembly suitable for implementation within a camera module. For example, in one embodiment, lens assembly  204  may include a lens stack  226  mounted within a support structure  228 . The lens stack  226  may, for example, include two lenses  230 ,  232  aligned along an optical axis between external window  234  and image sensor  208 , which facilitate transmission and/or focusing of light rays on image sensor  208 . Although not illustrated, lens assembly  204  may include numerous lenses, filters, and other optical components aligned along an optical axis to achieve various optical functionalities. External window  234  may, for example, be a transparent glass or polymer window located substantially coplanar with a mobile device housing. 
       FIG. 3  is a flowchart of a process for producing a camera module in accordance with one embodiment. Any one or more of the steps described in process  300  may be used to produce, for example, camera module  100  or module  200  described in reference to  FIG. 1  and  FIG. 2 , respectively. Representatively, process  300  may include providing a carrier having an adhesive layer attached thereto (block  302 ). The carrier may be any type of carrier suitable for carrying an image sensor die during a camera module assembly process. For example, the carrier may be a wafer, such as a ceramic wafer, or the like. The adhesive layer may be applied to a surface of the carrier and be made of any type of adhesive material capable of adhering an image sensor die to the carrier. Representatively, the adhesive layer may be a type of adhesive tape laminated to a surface of the carrier. 
     One or more image sensor dies may be attached to the adhesive layer of the carrier (block  304 ). Representatively, a pick and place technique may be used to pick one or more preformed dies from a batch and then place them in desired locations on the adhesive layer such that a batch of dies are attached to the carrier for subsequent processing operations. The dies may be any one or more of dies  106  or  206  previously discussed in reference to  FIG. 1  and  FIG. 2 , respectively. The dies may be placed on the carrier such that the side having the image sensor is exposed and facing away from the carrier. In other words, where the image sensor is on the top side of the die, the bottom side of the die is attached to the carrier. 
     Once the dies are attached to the carrier, a transparent member (e.g. transparent member  120  or  220 ) may be attached to each die (block  306 ). The transparent member is a glass window positioned over the die image sensor. In some embodiments, a glue, epoxy resin, resin or chemical bonding may be used to attach the transparent member to the die. In some cases, an optional plasma surface treatment technique may be used to facilitate attachment of the transparent member to the die. For example, a plasma gas may be applied to the die surface to enhance adhesion between the transparent member and the die. 
     Once the transparent member is attached to each die, a casing is molded around the dies to form image sensor devices (block  308 ). For example, in one embodiment, the casing is molded around the transparent member and die using an overmolding or injection molding process in which a mold material (e.g. epoxy resin) is injected around the components and then cured to form an overmolded image sensor device. In embodiments where several dies are attached to the carrier, the casing encases each of the dies such that all the dies are molded together on the carrier. In this aspect, the casing itself may serve as a die or image sensor device carrier during subsequent processing operations. 
     Representatively, the overmolded image sensor devices may be removed (e.g. picked) as a single unit from the adhesive so that processing of the bottom side of each device may occur (block  310 ). In some cases, either before or after removal of the image sensor devices from the carrier, the casing may be cured, such as by a thermal process. Since both sides of the image sensor devices are now exposed, one or more conductive layers can be formed on the surface of the die to redistribute an electrical connection formed through the die (e.g. vias  114 ) to a nearby device or component (block  312 ). The conductive layer may, for example, be a redistribution layer that is made of a metal material sputtered in a particular pattern along the die and casing. 
     The image sensor devices having the added conductive layers may be re-mounted to the carrier using the adhesive layer for further processing (block  314 ). Representatively, the further processing may include singulating or separating each of the image sensor devices on the carrier from one another (block  316 ). For example, the image sensor devices may be separated mechanically, such as by sawing through portions of the casing between each of the assemblies while the assemblies remain attached to the carrier, or a chemical process, such as by a chemical etching process. 
     Process  300  may further include attaching a lens assembly to each of the image sensor devices (block  318 ). The lens assembly may, for example, be any of lens assemblies  104 ,  204  previously discussed in reference to  FIG. 1  and  FIG. 2 . Representatively, a manifold assembly having one or more lens assemblies attached thereto may be used to position and attach lens assemblies to respective ones of the image sensor devices. The image sensor devices having lens assemblies attached thereto may be subjected to a batch curing technique to cure the adhesive or mounting material (e.g. glue) used to attach the lens assemblies to the image sensor devices to form the final camera modules. 
       FIG. 4 - FIG. 14  are pictorial views illustrating operations in forming a camera module in accordance with an embodiment. Referring to  FIG. 4 ,  FIG. 4  illustrates a carrier  402  having an adhesive layer  404  attached thereto. In one embodiment, carrier  402  may be a wafer or other type of carrier member suitable for supporting image sensor dies during a camera module assembly process as described herein. Adhesive layer  404  may be, for example, a layer of tape having a back side that is laminated to the carrier  402  and an adhesive side exposed. The adhesive side may have adhesive properties sufficient to adhere an image sensor die during a processing operation while also allowing for removal of the die without damaging the die when a sufficient force is applied. 
       FIG. 5  illustrates the further processing operation of attaching a die to the carrier described in  FIG. 4 . Representatively, one or more of dies  506 , similar to dies  106  and  206  described in reference to  FIG. 1  and  FIG. 2 , respectively, are attached to the adhesive layer  404  of carrier  402 . Each of dies  506  may be identical therefore for ease of illustration, only features of one of dies  506  are labeled in the Figures, but such labels should be understood as applying to the identical features illustrated in each of dies  506 . In particular, each of dies  506  may include one or more of a via  514  and image sensor  508 . In embodiments where the image sensor  508  is positioned on the top side of die  506 , as illustrated in  FIG. 5 , the bottom side of die  506  is positioned on and attached to the adhesive layer  404  such that further processing may be performed on the top side of dies  506 . In some embodiments, a pick and place technique may be used to place dies  506  on adhesive layer  404 . For example, each of dies  506  may be picked from a batch of preformed image sensor dies and placed at predetermined processing locations on adhesive layer  404 . 
       FIG. 6  illustrates the further processing operation of attaching a transparent member to the die(s) described in reference to  FIG. 5 . Representatively, a transparent member  602 , such as a window made of a glass or other transparent material, is positioned over image sensor  508  and attached to die  506  to form image sensor devices  606 . In one embodiment, transparent member  602  may be attached using mounting members  604 . Representatively, in one embodiment, mounting members  604  may be made of a material that can be, for example, subjected to, or used in connection with, a plasma technique to enhance the attachment between transparent member  602  and die  506 . Representatively, mounting members  604  may be an epoxy or other similarly suitable mounting material. In addition, mounting members  604  should serve as spacers between transparent member  602  and image sensor  508  such that a space or gap is formed between the two. 
       FIG. 7  illustrates the further processing operation of applying a protective film and mold cope over the transparent member of  FIG. 6 . The protective film  702  may be a layer of material that is removably applied over the exposed side of transparent member  602  to protect transparent member  602  during a further processing operation. For example, in one embodiment, protective film  702  may be an adhesive film, which is positioned over transparent member  602 . Once the protective film  702  is in place, a mold cope  704  may be applied (e.g. lowered) over the protective film  702 . The mold cope  704  may serve to enclose the image sensor device  606  between cope  704  and carrier  402  so that the mold material can be injected around each die assembly attached to carrier  402 . 
     Representatively, as shown in  FIG. 8 , a mold material  802  (e.g. an epoxy resin or the like) is injected, poured or otherwise loaded into the space between mold cope  704 / protective film  702  and carrier  402 /adhesive layer  404  such that it surrounds each of the image sensor devices  606  attached to carrier  402 . Once injected, the mold material  802  may be cured (such as by a heat) so that it forms a hard casing or overmold around each image sensor device  606 . 
     Once the casing is formed, the mold cope  704 , protective film  702  and carrier  402  with adhesive layer  404  may be removed from the overmolded batch of die assemblies to form image sensor devices  606  as shown in  FIG. 9 . Since the image sensor devices  606  are encased within the overmolded casing  902 , they remain in the same position as they were when attached to the carrier and therefore further processing may be performed on the devices  606  using the casing  902  as the carrier. Any suitable removal steps, and in any order, may be used. For example, in one embodiment, mold cope  704  and protective film  702  are first removed by applying a suitable force to expose the top side of each of the image sensor devices  606  followed by removal of adhesive layer  404  and carrier  402  to expose a bottom side of each of the image sensor devices  606  for further processing. 
     With the top and bottom surfaces of the image sensor devices  606  exposed, further processing on these surfaces can occur. Representatively,  FIG. 10  illustrates the further processing operation of applying conductive layers to the image sensor device and casing described in  FIG. 9 . The conductive layers  1002  may, for example, be metallization layers applied using a sputtering technique. The conductive layers  1002  may serve as redistribution layers that redistribute an electrical connection from the image sensor devices  606  to other locations outside of the associated die. For example, conductive layers  1002  may be formed along a bottom side of die  506 , from vias  514  to another location on casing  902 . 
       FIG. 11  illustrates the further processing operation of re-attaching the image sensor devices and casing to the carrier. Representatively, with processing on the bottom side of image sensor devices  606  complete, the bottom side of the devices may be re-attached to the adhesive layer  404  of the carrier  402  for further processing. 
       FIG. 12  illustrates the further processing operation of separating the image sensor devices from one another. Representatively, recesses  1202  may be formed through portions of casing  902  between each of devices  606  to form separately overmolded image sensor devices  1204 . The recesses  1202  may be formed by, for example, a sawing operation or other similar technique suitable for forming recesses around devices molded in a casing  902 . It is noted that while overmolded image sensor devices  1204  are now separately encased, they are still attached to carrier  402  therefore their location on carrier is maintained for further processing operations as desired. 
       FIG. 13  illustrates the further processing operation of attaching a lens assembly to the overmolded image sensor devices of  FIG. 12 . Representatively, while devices  1204  are attached to carrier  402 , lens assemblies  1302 , such as those previously discussed in reference to  FIG. 1  and  FIG. 2 , may be attached to respective ones of the overmolded image sensor devices  1204  to form assembled camera modules  1304 . The lens assemblies  1302  may be attached to the overmolded image sensor devices  1204  using any standard technique. For example, the lens assemblies  1302  may be positioned over respective ones of the devices  1204  and then attached using an adhesive, mechanical, chemical or other suitable attachment technique. 
       FIG. 14  illustrates the further processing operation of removing the carrier from the assembled camera modules. Representatively, camera modules  1304  are removed from carrier  402  by, for example, applying a force sufficient to overcome an adhesive force between adhesive layer  404  and camera modules  1304 . Once removed from carrier  402 , camera modules  1304  are separable units that may then be transferred and integrated into the desired electronic device. 
       FIG. 15  is a flowchart of a method of producing a camera module in accordance with another embodiment. One or more of the steps described in process  1500  may be used to produce, for example, camera module  200  described in reference to  FIG. 2 . Representatively, process  1500  may include providing a carrier having an adhesive layer attached thereto (block  1502 ). The carrier may be any type of carrier suitable for carrying an image sensor die during a camera module assembly process. For example, the carrier may be a ceramic wafer or the like. The adhesive layer may be applied to a surface of the carrier and be made of any type of adhesive material capable of adhering an image sensor die to the carrier. Representatively, the adhesive layer may be a type of adhesive tape laminated to a surface of the carrier. 
     One or more image sensor dies may be attached to the adhesive layer of the carrier using, for example, a pick and place technique (block  1504 ). The dies may be any one or more of dies  106  or  206  previously discussed in reference to  FIG. 1  and  FIG. 2 , respectively. For example, the dies may include image sensors and conductive vias formed through the dies such that electrical connections can be made through the dies and a ceramic substrate around the die to facilitate electrical connections is not required. The dies may be placed on the carrier such that the side having the image sensor is exposed and facing away from the carrier. In other words, where the image sensor is on the top side of the die, the bottom side of the die is attached to the carrier. 
     Once the die is attached to the carrier, a protective film may be positioned over the exposed side of the die to protect the die during subsequent overmolding operation (block  1506 ). The protective film may be any type of film suitable for preventing damage to the die during, for example, a molding process. It is noted that in this embodiment, in contrast to the processing operation described in reference to  FIG. 7 , the protective film is applied over the die before adding the transparent member (e.g. window) over the image sensor on the die. 
     With the protective film over the die, a mold cope is placed over the protective film (block  1508 ). A first overmold casing may then be formed around the die (block  1510 ). Representatively, the first casing may be formed by injecting, or otherwise introducing, a mold material between the mold cope and the carrier such that it surrounds the die sandwiched therebetween. Once the mold material is cured, the mold cope and protective film may be removed leaving behind a number of dies overmolded together on the carrier (block  1512 ). 
     With the top sides of the dies now exposed, a first conductive layer (e.g. conductive layer  242  described in reference to  FIG. 2 ) may be applied to the top side of each die (block  1514 ). The first conductive layer may be substantially similar to the previously discussed conductive layer described in reference to (block  314 ) of  FIG. 3  except that it is on a top side rather than a bottom side of the die. 
     Process  1500  may further include mounting an electronic device to the die and first casing (block  1516 ). The electronic device may be, for example, an electronic device such as electronic device  240  described in reference to  FIG. 2 . The electronic device may be electrically connected to the first conductive layer such that an electrical connection is made between the die and the electronic device. 
     In addition, a transparent member may be attached over the image sensor of the die to protect the die during subsequent processing operations and complete the image sensor device (block  1518 ). The image sensor device and electronic device may then be encased within a second casing (block  1520 ). Representatively, a protective film and mold cope may be positioned over the transparent member such that the image sensing device is sandwiched between the cope/film layer and the carrier as described in reference to (block  308 ) of  FIG. 3 . A molding material (e.g. epoxy resin) may then be introduced (e.g. injected) between the cope/film layer and carrier and around each of the image sensing devices. 
     With the image sensing devices and electronic devices encased within a casing (e.g. the first and second casing), the entire encased module may be removed from the carrier so that subsequent processing may be performed on the bottom side (or the top side) of the image sensing devices. Representatively, a second conductive layer (e.g. redistribution layer) may be applied to the bottom side of the die and casing (block  1522 ) as previously discussed in reference to (block  314 ) of  FIG. 3 . Finally, a lens assembly may be attached to each of the overmolded image sensing devices (block  1524 ) as previously discussed in reference to  FIG. 3  and  FIG. 13 . The devices with lens assemblies attached may then be separated (such as by sawing and removing them from the carrier) to form singulated overmolded camera modules having an embedded electronic device. The modules formed according to process  1500  benefit from a decreased z-height because the electronic device is embedded in the casing, as opposed to mounted on top of, for example, a ceramic substrate surrounding the die. 
     It should further be recognized the processing operations described in  FIG. 3 - FIG. 15  allow for the formation of a very compact camera module with fewer processing operations and are therefore easier to manufacture. For example, the resulting camera module may have the smallest possible z-height dimension from the bottom of the die to the transparent member due to the elimination of the ceramic substrate carrier. In addition, the x and y dimensions of the camera module may be reduced because an under fill material, which is typically used between the die and the ceramic substrate to attach the two together, is no longer necessary. Instead, the casing is molded directly to, and contacts, exposed surfaces of the die. Still further, the manufacturing process is simplified because some operations typically used in assembling camera modules are no longer necessary, for example, operations such as loading dies into a carrier boat, applying an under fill between the die and ceramic substrate, curing of the under fill and flip chip operations. 
       FIG. 16  illustrates one embodiment of a simplified schematic view of one embodiment of an electronic device in which a camera module may be implemented. As seen in  FIG. 16 , the overmolded camera module may be integrated within a consumer electronic device  1602  such as a smart phone with which a user can conduct a call with a far-end user of a communications device  1604  over a wireless communications network; in another example, the overmolded camera module may be integrated within the housing of a tablet computer. These are just two examples of where the camera module described herein may be used, it is contemplated, however, that the overmolded camera module may be used with any type of electronic device in which a camera module is desired, for example, a tablet computer, a desk top computing device or other display device. 
       FIG. 17  illustrates a block diagram of some of the constituent components of an embodiment of an electronic device in which an embodiment of the invention may be implemented. Device  1700  may be any one of several different types of consumer electronic devices. For example, the device  1700  may be any camera-equipped mobile device, such as a cellular phone, a smart phone, a media player, or a tablet-like portable computer. 
     In this aspect, electronic device  1700  includes a processor  1712  that interacts with camera circuitry  1706 , motion sensor  1704 , storage  1708 , memory  1714 , display  1722 , and user input interface  1724 . Main processor  1712  may also interact with communications circuitry  1702 , primary power source  1710 , speaker  1718 , and microphone  1720 . The various components of the electronic device  1700  may be digitally interconnected and used or managed by a software stack being executed by the processor  1712 . Many of the components shown or described here may be implemented as one or more dedicated hardware units and/or a programmed processor (software being executed by a processor, e.g., the processor  1712 ). 
     The processor  1712  controls the overall operation of the device  1700  by performing some or all of the operations of one or more applications or operating system programs implemented on the device  1700 , by executing instructions for it (software code and data) that may be found in the storage  1708 . The processor  1712  may, for example, drive the display  1722  and receive user inputs through the user input interface  1724  (which may be integrated with the display  1722  as part of a single, touch sensitive display panel). In addition, processor  1712  may send an audio signal to speaker  1718  to facilitate operation of speaker  1718 . 
     Storage  1708  provides a relatively large amount of “permanent” data storage, using nonvolatile solid state memory (e.g., flash storage) and/or a kinetic nonvolatile storage device (e.g., rotating magnetic disk drive). Storage  1708  may include both local storage and storage space on a remote server. Storage  1708  may store data as well as software components that control and manage, at a higher level, the different functions of the device  1700 . 
     In addition to storage  1708 , there may be memory  1714 , also referred to as main memory or program memory, which provides relatively fast access to stored code and data that is being executed by the processor  1712 . Memory  1714  may include solid state random access memory (RAM), e.g., static RAM or dynamic RAM. There may be one or more processors, e.g., processor  1712 , that run or execute various software programs, modules, or sets of instructions (e.g., applications) that, while stored permanently in the storage  1708 , have been transferred to the memory  1714  for execution, to perform the various functions described above. 
     The device  1700  may include communications circuitry  1702 . Communications circuitry  1702  may include components used for wired or wireless communications, such as two-way conversations and data transfers. For example, communications circuitry  1702  may include RF communications circuitry that is coupled to an antenna, so that the user of the device  1700  can place or receive a call through a wireless communications network. The RF communications circuitry may include a RF transceiver and a cellular baseband processor to enable the call through a cellular network. For example, communications circuitry  1702  may include Wi-Fi communications circuitry so that the user of the device  1700  may place or initiate a call using voice over Internet Protocol (VOIP) connection, transfer data through a wireless local area network. 
     The device may include a microphone  1720 . In this aspect, microphone  1720  may be an acoustic-to-electric transducer or sensor that converts sound in air into an electrical signal. The microphone circuitry may be electrically connected to processor  1712  and power source  1710  to facilitate the microphone operation (e.g. tilting). 
     The device  1700  may include a motion sensor  1704 , also referred to as an inertial sensor, that may be used to detect movement of the device  1700 . The motion sensor  1704  may include a position, orientation, or movement (POM) sensor, such as an accelerometer, a gyroscope, a light sensor, an infrared (IR) sensor, a proximity sensor, a capacitive proximity sensor, an acoustic sensor, a sonic or sonar sensor, a radar sensor, an image sensor, a video sensor, a global positioning (GPS) detector, an RF or acoustic doppler detector, a compass, a magnetometer, or other like sensor. For example, the motion sensor  1704  may be a light sensor that detects movement or absence of movement of the device  1700 , by detecting the intensity of ambient light or a sudden change in the intensity of ambient light. The motion sensor  1704  generates a signal based on at least one of a position, orientation, and movement of the device  1700 . The signal may include the character of the motion, such as acceleration, velocity, direction, directional change, duration, amplitude, frequency, or any other characterization of movement. The processor  1712  receives the sensor signal and controls one or more operations of the device  1700  based in part on the sensor signal. 
     The device  1700  also includes camera circuitry  1706  that implements the digital camera functionality of the device  1700 . One or more camera modules having image sensors (e.g. camera module  100  or camera module  200 ) are built into the device  1700 , and each may be located at a focal plane of an optical system that includes a respective lens. An optical image of a scene within the camera&#39;s field of view is formed on the image sensor, and the sensor responds by capturing the scene in the form of a digital image or picture consisting of pixels that may then be stored in storage  1708 . The camera circuitry  1706  may also be used to capture video images of a scene. 
     Device  1700  also includes primary power source  1710 , such as a built in battery, as a primary power supply. 
     In the foregoing specification, the invention has been described with reference to specific exemplary embodiments thereof. It will be evident that various modifications may be made thereto without departing from the broader spirit and scope of the invention as set forth in the following claims. The specification and drawings are, accordingly, to be regarded in an illustrative sense rather than a restrictive sense.

Metadata:
Filing Date: 20160809
Publication Date: 20170919
Grant Date: 20170919
Priority Date: 20150202
Inventors: Vittu Julien C.
Assignee: APPLE INC
CPC Classifications: [{"code": "H04N23/57", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04N23/55", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04N23/54", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01L2924/19104", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01L23/3185", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01L2924/16235", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01L2224/04105", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01L2224/18", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01L21/568", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01L21/565", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01L31/02325", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01L27/14618", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01L21/565", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01L27/14685", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01L27/14625", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01L23/3185", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01L27/14636", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01L21/568", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10F77/407", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10F39/811", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10F39/806", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10F39/804", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10F39/811", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10F39/806", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10F39/804", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10F39/024", "inventive": true, "first": true, "tree": "[]"}, {"code": "H10F39/024", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01L2924/16235", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01L2224/18", "inventive": false, "first": false, "tree": "[]"}]
Family ID: 56554666