Abstract:
There is provided a camera module package including: a substrate having an image sensor disposed on one surface thereof and a pad electrically connected to the image sensor; a protective cap adhered onto the substrate by an adhesive surrounding the image sensor to seal the image sensor, the protective cap transmitting light; and a supporting part surrounding the protective cap, the supporting part adhering and supporting at least one lens formed corresponding to the image sensor. The camera module package is reduced in thickness and size, and minimized in an error of a focal length between the lens and the image sensor, thereby achieving accuracy and high reliability.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the priority of Korean Patent Application No. 2007-0053553 filed on May 31, 2007, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a camera module package including a substrate where an image sensor and a through electrode are formed and a protective cap and a lens disposed on the substrate. 
         [0004]    2. Description of the Related Art 
         [0005]    A sensor module such as a charge-coupled device (CCD) image sensor and a complementary metal-oxide semiconductor (CMOS) image sensor is utilized as a module for a conventional optical apparatus. 
         [0006]      FIG. 1  is a cross-sectional view illustrating-configuration of a conventional camera module. The camera module of  FIG. 1  includes a lens  10 , a tubular-shaped housing  20  holding the lens and a circuit substrate  40 . Also, the camera module includes a substrate  30 , and an image sensor  32 , a micro lens  34  and an electrode pad  36  formed on the substrate  30 . A rear surface of the substrate  30  is die-bonded to the circuit substrate  40  by an adhesive  44 , and the electrode pad  36  is electrically connected to a conductive circuit  42  formed on the circuit substrate  40  by a bonding wire  38 . 
         [0007]    The housing  20  has one opening sealed by a glass cover  12  and an adhesive  14  opposing the lens  10 , and another opening sealed by the circuit substrate  40  and another adhesive  46 . This allows the image sensor  32  and the micro lens  34  to be protected from external environment. Before the housing  20  is sealed, the image sensor  32  and the micro lens  34  need to be protected by other means. 
         [0008]    The aforesaid camera module requires a space where the electrode pad  36  and the conductive wire  42  are connected together via the bonding wire  38 . Moreover, the image sensor  32  is shielded from light and thus the bonding wire  38  and the electrode pad  36  cannot be disposed on the image sensor or the micro lens  34 . In consequence, the conventional camera module is hardly miniaturizable. Besides, the housing having the lens attached thereon and the substrate having the image sensor disposed thereon are attached on the circuit substrate, respectively, thereby resulting in accumulation of tolerance. Therefore, an error in a focal length between the lens and the image sensor renders it hard to manufacture a precise camera module. 
       SUMMARY OF THE INVENTION 
       [0009]    An aspect of the present invention provides a more precise camera module package in which a lens is directly mounted on a substrate having a through electrode formed thereon to assure a smaller sized camera module package and minimize an error of a focal length between the lens and the image sensor. 
         [0010]    According to an aspect of the present invention, there is provided a camera module package including: a substrate having an image sensor disposed on one surface thereof and a pad electrically connected to the image sensor; a protective cap adhered onto the substrate by an adhesive surrounding the image sensor to seal the image sensor, the protective cap transmitting light; and a supporting part surrounding the protective cap, the supporting part adhering and supporting at least one lens formed corresponding to the image sensor. 
         [0011]    A micro lens may be disposed on a top of the image sensor. 
         [0012]    The supporting part may be formed without interruption inside the pad. 
         [0013]    The camera module package may further include a pad protection cap on a top of the pad. 
         [0014]    The supporting part may be formed without interruption to cover a top of the pad. 
         [0015]    The protective cap may have an infrared filter applied on one surface thereof. 
         [0016]    The camera module package may further include a through electrode which is disposed in the device wafer connecting to the pad on one surface of the device wafer. 
         [0017]    The camera module package may further include a external electrode on another surface of the device wafer connecting to the through electrode. 
         [0018]    According to another aspect of the present invention, there is provided a method of manufacturing a camera module package, the method including: providing a base wafer having a protective cap disposed thereon; providing a device wafer having an image sensor disposed on one surface thereof to correspond to the protective cap, an adhesive formed around the image sensor and a pad electrically connected to the image sensor; adhering the protective cap onto the device wafer by the adhesive; forming a through electrode on one surface of the device wafer to connect to the pad and forming an external electrode on another surface of the device wafer to connect to the through electrode; bonding the device wafer and the lens wafer together on the one surface of the device wafer by a supporting part, the supporting part covering the pad and surrounding the protective cap; and dicing a camera module package including the image sensor into individual units. 
         [0019]    The providing a base wafer may include bonding the protective cap on the one surface of the base wafer and removing a portion excluding the protective cap from the protective cap wafer. 
         [0020]    The method may further include removing the base wafer, before the supporting part is provided. 
         [0021]    The method may further include polishing the device wafer before the forming an external electrode. 
         [0022]    According to still another aspect of the present invention, there is provided a method of manufacturing a camera module package, the method including: providing a base wafer having a protective cap and a pad protection cap disposed thereon; providing a device wafer having an image sensor disposed on one surface thereof to correspond to the protective cap, a pad formed on an area corresponding to the pad protection cap to electrically connect to the image sensor and an adhesive formed around the image sensor and on the pad, respectively; bonding the protective cap and the pad protection cap onto the device wafer by the adhesive; forming a through electrode on one surface of the device wafer to connect to the pad and forming an external electrode on another surface of the device wafer to connect to the through electrode; bonding the device wafer and the lens wafer onto the one surface of the device wafer by a supporting part, the supporting part formed without interruption between the protective cap and the pad protection cap; dividing the lens wafer into individual lenses to expose the pad protection cap to the outside; and dicing a camera module package including the image sensor into individual units. 
         [0023]    The providing a base wafer may include bonding a protective cap wafer on the one surface of the base wafer and removing portions excluding the protective cap and the pad protection cap from the protection cap wafer. 
         [0024]    The method may further include removing the base wafer before the supporting part is provided. 
         [0025]    The method may further include polishing the device wafer before the forming an external electrode. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0026]    The above and other aspects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which: 
           [0027]      FIG. 1  is a cross-sectional view illustrating a conventional camera module package; 
           [0028]      FIG. 2  is a cross-sectional view illustrating a camera module package according to an exemplary embodiment of the invention; 
           [0029]      FIGS. 3A to 3E  are procedural views illustrating a method of manufacturing a camera module package according to an exemplary embodiment of the invention; 
           [0030]      FIG. 4  is a cross-sectional view illustrating a camera module package according to another exemplary embodiment of the invention; and 
           [0031]      FIGS. 5A to 5F  are procedural views illustrating a method of manufacturing a camera module package according to another exemplary embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0032]    Exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. 
         [0033]      FIG. 2  is a cross-sectional view illustrating a camera module according to an exemplary embodiment of the invention.  FIGS. 3A to 3D  are procedural views illustrating a method of manufacturing a camera module package according to an exemplary embodiment of the invention.  FIG. 4  is a cross-sectional view illustrating a camera module package according to another exemplary embodiment of the invention.  FIGS. 5A to 5E  are procedural views illustrating a method of manufacturing a camera module package according to another exemplary embodiment of the invention. 
         [0034]    As shown in  FIG. 2 , the camera module package  100  of the present embodiment includes a lens  110 , a substrate  120 , a protective cap  140  and a supporting part  130 . 
         [0035]    The substrate  120  is provided on one surface thereof with an image sensor  122  imaging light passing through the lens  110  and converting the imaged light into an electrical signal. A pad  126  is disposed on an outer periphery of the image sensor  122  to connect to the image sensor  122  by an unillustrated pattern circuit. 
         [0036]    A micro lens  124  is disposed on a top of the image sensor  122 . 
         [0037]    The protective cap  140  is bonded onto the substrate to cover the image sensor  122  by an adhesive  142  formed on the one surface of the substrate. 
         [0038]    The adhesive  142  is applied without interruption along an edge of the image sensor  122 . 
         [0039]    The protective cap  140 , when bonded on the one surface of the substrate by the adhesive  142 , seals and protects the image sensor  122  and the micro lens  124  from external environment. 
         [0040]    The protective cap  140  is a transparent member formed of a light transmissive material. For example, the protective cap  140  may be a glass substrate. 
         [0041]    Also, an infrared (IR) filter (not shown) may be applied on one surface of the protective cap  140  to filter infrared rays of light passed through the lens  110 . 
         [0042]    This IR filter is disposed on a bottom of the protective cap  140  to correspond to the image sensor  122  and sealed by the adhesive  142  to be protected from external environment together with the image sensor  122 . 
         [0043]    The pad  126  is electrically connected to a through electrode  128  extending through the substrate  120 . 
         [0044]    The through electrode  128  is electrically connected to an external electrode  129  formed on another surface of the substrate  120 , and the substrate  120  is bonded to a main substrate (not shown) by the external electrode  129 . 
         [0045]    The supporting part  130  is formed on the one surface of the substrate  120  to support the lens  110  as an adhesive bonding the lens  110  and the substrate  120  to each other. 
         [0046]    The supporting part  130  surrounds the protective cap  140  above the pad  126 , and is formed without interruption at a predetermined height. 
         [0047]    The supporting part  130  has a height so as to be protruded higher than the protective cap  140 . This prevents a bottom of the lens  110  from contacting a top of the protective cap  140 . 
         [0048]    An infrared image sensor (IRIS) (not shown) may be applied on a top of the lens  110  attached to the supporting part  130  to adjust incident light. 
         [0049]    A method of manufacturing a camera module  100  according to an exemplary embodiment of the invention includes providing a base wafer having a protective cap thereon, providing a device wafer, bonding a protective cap and a device wafer together, forming an external electrode, bonding a device wafer and a lens wafer together, and dicing. 
         [0050]    As shown in  FIG. 3A , in providing the base wafer and the device wafer, the base wafer  148  has the protective cap  140  formed on one surface thereof, and the device wafer  120 ′ has an image sensor formed on one surface thereof to correspond to the protective cap. Also, a plurality of pads  126  are formed on an outer periphery of the image sensor  122  to connect to the image sensor  122  by a pattern circuit. An adhesive  142  is formed along an outer edge of the image sensor  122 . 
         [0051]    To form the protective cap  140 , a protective cap wafer  140 ′ is bonded onto one surface of the base wafer  148  and then an area of the protective cap wafer  140 ′ excluding a portion corresponding to the image sensor  122 , as indicated with a dotted line, is removed by etching, or half-dicing. 
         [0052]    Here, the base wafer  148  may be a transparent silicon wafer and the protective cap wafer  140 ′ may be a glass wafer. 
         [0053]    Also, a micro lens  124  is disposed on a top of the image sensor  122 . 
         [0054]    Next, in bonding the protective cap and the device wafer together, and forming the external electrode, as shown in  FIG. 3B , the protective cap  140  is bonded to the device wafer  120 ′ by the adhesive  142  of the device wafer  120 ′. Also, a plurality of through electrodes  128  are formed to extend through the device wafer  120 ′ to electrically connect to the pads  126 , respectively. External electrodes  129  are formed on another surface of the device wafer  120 ′ to connect to the through electrodes  128 , respectively. 
         [0055]    Each of the through electrodes  128  defines a via from the another surface of the device wafer  120 ′. The via is filled with a conductive material or has an inner surface applied with a conductive material. 
         [0056]    Moreover, to reduce a height of the camera module, the device wafer  120 ′ may have the another surface thereof polished before the external electrodes  129  are formed. 
         [0057]    After forming the external electrodes  129 , as shown in  FIG. 3C , the base wafer  148  is removed. 
         [0058]    The base wafer  148  is removed by grinding, polishing, etching, thermal release, ultraviolet (UV) release and the like, while leaving only the protective cap  140 . 
         [0059]    Removal of the base wafer  148  is preceded by formation of the external electrodes  129 , but the present embodiment is not limited thereto. The removal of the base wafer  148  can be performed as long as it is prior to forming a supporting part  130 , which will be described later. 
         [0060]    To bond the device wafer and the lens wafer together, as shown in  FIG. 3D , the supporting part  130  is formed on one surface of the device wafer  120 ′ and the device wafer  120 ′ and the lens wafer  110 ′ are bonded together via the supporting part  130 . 
         [0061]    The lens wafer  110 ′ is a light transmissive wafer where a lens  110  is disposed corresponding to the image sensor  122  formed on the device wafer  120 ′. 
         [0062]    The supporting part  130  is formed on the one surface of the device wafer  120 ′ to surround the protective cap  140  and be positioned over a top of each of the pads  126 . 
         [0063]    This supporting part  130  is applied at a predetermined height so as to be protruded higher than a top of the protective cap  140 , thereby supporting the lens wafer  110 ′ at a predetermined distance from the image sensor  122 . 
         [0064]    The supporting part  130  may be formed with interruption. However, the supporting part  130  may be formed without interruption to prevent the lens  110  from tilting and accordingly an optical axis from being misaligned. 
         [0065]    When dicing is performed, as shown in  FIG. 3E , the lens wafer  110 ′ and the device wafer  120 ′ are diced along a virtual trimming line D into individual camera module packages  100 . 
         [0066]    Meanwhile, a camera module  101  according to another exemplary embodiment of the invention, as shown in  FIG. 4 , includes a lens  110 , a substrate  120 , a protective cap  140  and a supporting part  130 ′. 
         [0067]    However, the same components as those in the camera module  100  of the previous embodiment will be designated with the same reference signs, and will be described in no more detail. 
         [0068]    As shown in  FIG. 4 , pad protection caps  144  are formed on a top of a pad  126  disposed on one surface of a substrate  120  by an adhesive  146 . 
         [0069]    The pad protection caps  144  cover pads  126 , respectively to protect the pads  126  from external environment, and may be formed of a material identical to that of the protective cap  140 . 
         [0070]    The supporting part  130 ′ is formed without interruption on the one surface of the substrate  120  to surround the protective cap  140  between the protective cap  140  and the pad protection caps  144 . The supporting part  130 ′ supports the lens  110  and bonds the lens  110  and the substrate  120  together. 
         [0071]    A method of manufacturing a camera module  101  according to another exemplary embodiment of the invention includes providing a base wafer having a protective cap and pad protection caps thereon, providing a device wafer, bonding the protective cap and the pad protection cap on the device wafer, forming an external electrode, bonding the device wafer and the lens wafer together, removing the lens wafer, and dicing. 
         [0072]    As shown in  FIG. 5A , when providing the base wafer and the device wafer, the base wafer  148  has the protective cap  140  and the pad protection caps  144 ′ formed thereon. The device wafer  120 ′ has an image sensor  122  formed on one surface thereof to correspond to the protective cap  140 . Also, a plurality of pads  126  are formed on an outer periphery of the image sensor  122  to correspond to the pad protection caps  144 ′, respectively. 
         [0073]    To form the protective cap  140  and the pad protection caps  144 ′, a protective wafer  140 ″ is bonded onto one surface of the base wafer  148  and then an area of the protective wafer  140 ″ excluding portions corresponding to the protective cap  140  and the pad protection caps  144 ′, as indicated with a dotted line, is removed by etching. 
         [0074]    Here, the base wafer  148  may be a transparent silicon wafer and the protective wafer  140 ″ may be a glass wafer. 
         [0075]    Also, an adhesive  146  is formed on the outer periphery of the image sensor  122  and a top of each of the pads  126  on the one surface of the device wafer  120 ′. 
         [0076]    Moreover, a micro lens  124  is disposed on a top of the image sensor  122 . 
         [0077]    When bonding the protective cap and the pad protection caps to the device wafer and forming the external electrode, as shown in  5 B, the protective cap  140  and the pad protection caps  144 ′ are bonded together by the adhesives  142  and  146 . 
         [0078]    In addition, a plurality of through electrodes  128  are formed to extend through the device wafer  120 ′ and to electrically connect to the pad  126 . External electrodes  129  are formed on another surface of the device wafer  120 ′ to connect to the plurality of through electrodes  128 , respectively. 
         [0079]    The through electrodes  128  define a via from the another surface of the device wafer  120 ′. The via is filled with a conductive material or has an inner surface applied with a conductive material. 
         [0080]    To reduce a height of the camera module, the device wafer  120 ′ may have the another surface polished before the external electrodes  129  are formed. 
         [0081]    After forming the external electrodes  129 , as shown in  FIG. 5C , the base wafer  148  is removed. 
         [0082]    To remove the base wafer  148 , the base wafer  148  is polished by grinding or polishing, while leaving the protective cap  140  and the pad protection caps  144 ′. 
         [0083]    Removal of the base wafer  148  is preceded by formation of the external electrodes  129 , but the present embodiment is not limited thereto. The removal of the base wafer  148  can be performed as long as it is prior to forming supporting parts  130 ′, which will be described later. 
         [0084]    To bond the device wafer and the lens wafer together, as shown in  FIG. 5D , the supporting parts  130 ′ are formed on the one surface of the device wafer  120 ′, and the device wafer  120 ′ and the lens wafer  110 ′ are bonded together via the supporting part  130 ′. 
         [0085]    The lens wafer  110 ′ is a light transmissive wafer where a lens  110  is disposed corresponding to the image sensor  122  formed on the device wafer  120 ′. 
         [0086]    The supporting parts  130 ′ are applied as an adhesive on the one surface of the device wafer  120 ′ to surround the protective cap  140  between the protective cap  140  and the pad protection caps  144 ′. 
         [0087]    This supporting part  110 ′ is applied at a predetermined height so as to be protruded higher than a top of the protective cap  140 , thereby supporting the lens wafer  110 ′ at a predetermined distance from the image sensor  122 . 
         [0088]    The supporting parts  130 ′ may be formed with interruption. However, the supporting parts  130 ′ may be formed without interruption to prevent the lens  110  from tilting and accordingly an optical axis from being misaligned. 
         [0089]    When the lens wafer is divided, as shown in  FIG. 5E , an adjacent portion between the supporting parts  130 ′ is removed from the lens wafer  110 ′ by dry etching or half-dicing. 
         [0090]    This allows the lens wafer  110 ′ to be divided into individual lenses  110  and the pad protection caps  144 ′ to be exposed outward. 
         [0091]    When dicing is performed, as shown in  FIG. 5F , the pad protection caps  144 ′ and the device wafer  120 ′ are diced along a virtual trimming line D into individual camera module packages  101 . 
         [0092]    In consequence, the camera module has the lens directly attached on the substrate to be minimized in height and also minimized in errors of a focal length between the lens and the image sensor resulting from tolerance of the adhesive. 
         [0093]    As set forth above, a camera module package according to exemplary embodiments of the invention has a lens directly attached on a substrate to be reduced in thickness and size. Also, the camera module package has only a supporting part disposed between the lens and the substrate to ensure minimal errors of a focal length between the lens and the image sensor. This allows for a more precise and more highly reliable camera module package. 
         [0094]    While the present invention has been shown and described in connection with the exemplary embodiments, it will be apparent to those skilled in the art that modifications and variations can be made without departing from the spirit and scope of the invention as defined by the appended claims.