Abstract:
The present invention discloses an electrical device with a connection interface, a circuit board thereof, and a method for manufacturing the same. The electrical device with a connection interface includes: a circuit board on which a first circuit layer and a second circuit layer are formed and the second circuit layer has plural terminal pads, wherein a cavity is formed in the terminal pads and extends to the first circuit layer, and a metal layer is disposed in the cavity and connected to the first circuit layer and the terminal pads and defines an opening; a semiconductor chip electrically connected to the first circuit layer; and a conductive element interlaid in the opening. The electrical device with a connection interface does not need to be formed by assembling a terminal module because the conductive element is directly mounted on the circuit board.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefits of the Taiwan Patent Application Serial Number 100141895, filed on Nov. 16, 2011, the subject matter of which is incorporated herein by reference. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to an electrical device, a circuit board thereof and methods for manufacturing the same and, more particularly, to an electrical device with a connection interface, a circuit board thereof and methods for manufacturing the same. 
         [0004]    2. Description of Related Art 
         [0005]    As the development of portable electronic devices, electronic cards or other electronic systems, the specifications of connection interfaces are also changed. For example, the specifications of Universal Serial Bus (USB) is developed from the original USB 1.0 to USB 2.0, and further moved to USB 3.0 used nowadays; and the development of USB is gradually moved on. 
         [0006]    Conventional connection interfaces can be referred to Taiwan Utility Model Patent M413989 issued on Oct. 11, 2011, which disclose a connection interface with terminal modules. The disclosed connection interface comprise a circuit board and a terminal module, wherein the circuit board and the terminal module of the connection interface are fabricated individually, and then conductive sheets and elastic terminals are laminated on the circuit board to electrically connect to each other. After the aforementioned process, a connection interface can be obtained. 
         [0007]    The conventional elastic terminals are generally disposed in the terminal module, and then the terminal module is laminated and assembled on the circuit board to obtain the purpose of electrically connecting the terminal module to the circuit board. Since the elastic terminals are not assembled on the circuit board directly, additional assembling process of the terminal module has to be performed. Therefore, the assembling process and the manufacturing cost are increased. 
       SUMMARY OF THE INVENTION 
       [0008]    An object of the present invention is to provide an electrical device with a connection interface, wherein an opening is formed on a circuit board. Hence, a conductive element can be interposed on the circuit board directly without using additional mounting terminal modules. Therefore, the assembly process can be simplified and the process reliability can further be improved. 
         [0009]    To achieve this object, an aspect of the present invention provides an electrical device with a connection interface, which comprises: a circuit board, a semiconductor chip and a conductive element. The circuit board has a first surface and a second surface corresponding to the first surface, a first circuit layer is disposed on the first surface, a second circuit layer is disposed on the second surface, the first circuit layer comprises plural conductive pads, the second circuit layer comprises a metal contacting pad and a terminal pad, a cavity is formed in the terminal pad and extends to the first circuit layer, a metal layer is disposed in the cavity, an opening is formed in the metal layer, and the metal layer electrically connects to the first circuit layer and the terminal pads. In addition, the semiconductor chip is disposed on the first surface and has plural electrode pads, wherein the electrode pads of the semiconductor chip electrically connect to the conductive pads of the first circuit layer respectively. Furthermore, the conductive element has a plug interlaid into the opening. 
         [0010]    In a preferred embodiment of the present invention, the electrical device with the connection interface may selectively comprise: a contacting layer disposed between the plug of the conductive element and the metal layer and/or the first circuit layer. When the electrical device comprises the contacting layer, the plug of the conductive element can be fixed on the circuit board stably, and the problem that the conductive element peels off due to external forces can be prevented. In addition, the electrical device with a connection interface of the present invention may further selectively comprise: an adhesive film disposed between the semiconductor chip and the first surface of the circuit board to fix the semiconductor chip on the circuit board stably. When there are several semiconductor chips laminate to each other, the adhesive film can be disposed between laminated semiconductor chips, so that these laminated semiconductor chips can be fixed to each other. 
         [0011]    In the electrical device with the connection interface of the present invention, the conductive element may further selectively comprise a buffer structure. The example of the shape of the buffer structure can be a bend shape, a curve shape, an open-ended parabolic shape, a hyperbolic shape, an irregular embossed shape, and a mushroom shape. The different design of the buffer structure can be applied to various requirements, and also be used as an identification mark. 
         [0012]    In a preferred embodiment of the electrical device with the connection interface of the present invention, the metal layer is disposed in the cavity formed in the terminal pad of the circuit board, and the opening penetrates through the metal layer. Hence, the opening extends to the first circuit layer, i.e. the opening exposes the first circuit layer. However, the depth and the shape of the opening are not particularly limited, as long as the plug of the conductive element can be interlaid and be fixed into the opening. Preferably, the shape and the depth of the opening are designed based on those of the plug. It means that the first circuit layer may not be exposed from the opening. In addition, the aforementioned metal contacting pad may be used as a golden finger. 
         [0013]    Furthermore, the electrical device with the connection interface of the present invention may selectively comprise: an insulating layer disposed on a surface of the first circuit layer and/or a surface of the second circuit layer, wherein the insulating layer has plural contacting windows to expose at least one of the conductive pads, the metal contacting pad, and the terminal pad. The insulating layer can protect the first circuit layer and the second circuit layer. The contacting windows correspond to the conductive pads, the metal contacting pad, and/or the terminal pad, in order to expose those elements for sequentially electrical connections. For example, the contacting windows can expose the conductive pads, and only the exposed area of the conductive pads is plated for further wire-bonding. By disposing the contacting windows, the area to be plated can be reduced, and thus the manufacturing cost can be further decreased. In another preferred embodiment of the present invention, the insulating layer is disposed on surfaces of both the first circuit layer and the second circuit layer. However, the disposition of the insulating layer is not limited thereto. The insulating layer may also be disposed on a surface of the first circuit layer or a surface of the second circuit layer. 
         [0014]    Another object of the present invention is to provide a method for manufacturing an electrical device with a connection interface, wherein an opening is formed on a circuit board. Hence, a conductive element can be interposed on the circuit board directly without using additional mounting terminal modules, so the assembly process can be simplified. 
         [0015]    To achieve this object, another aspect of the present invention is to provide a method for manufacturing an electrical device with a connection interface, which comprises the following steps: providing a circuit board with a first surface and a second surface corresponding to the first surface, wherein a first circuit layer is disposed on the first surface, a second circuit layer is disposed on the second surface, the first circuit layer comprises plural conductive pads, the second circuit layer comprises a metal contacting pad and a terminal pad, a cavity is formed in the terminal pad and extends to the first circuit layer, a metal layer is disposed in the cavity, the metal layer electrically connects to the first circuit layer and the terminal pads, and an opening is formed in the metal layer; disposing a semiconductor chip on the first surface of the circuit board, wherein the semiconductor chip has plural electrode pads, and the electrode pads electrically connect to the conductive pads of the first circuit layer respectively; and disposing a conductive element in the opening of the circuit board, wherein the conductive element has a plug, and the plug is interlaid into the opening. 
         [0016]    In the method for manufacturing the electrical device with the connection interface of the present invention, the cavity of the circuit board, the opening and the metal layer are formed through a method comprising the following steps: forming a cavity in the terminal pad, wherein the cavity extends to the first circuit layer; depositing a metal in the cavity; and forming an opening in the metal to form a metal layer which covers a surface of an inner wall of the cavity. According to the aforementioned steps, the area for disposing the conductive element on the circuit board is defined by two-steps of hole-forming process, and the conductive element can disposed on the circuit board directly without additional modules. 
         [0017]    The method for manufacturing the electrical device with the connection interface of the present invention may further comprise a step of: forming a contacting layer between the plug of the conductive element and the metal layer and/or the first circuit layer. In addition, the method of the present invention may also comprise a step of: forming an adhesive film between the semiconductor chip and the first surface of the circuit board. Herein, the adhesive film may also be used to fix to adjacent semiconductor chips. In addition, the method of the present invention may selectively comprise a step of: forming an insulating layer on a surface of the first circuit layer and/or a surface of the second circuit layer, wherein the insulating layer has plural contacting windows to expose at least one of the conductive pads, the metal contacting pad, and the terminal pad. In a preferred embodiment of the present invention, the step for forming the insulating layer may be performed before the semiconductor is disposed. However, the performing order of this step is not limited thereto, and can be adjust if it is required. 
         [0018]    A further object of the present invention is to provide a circuit board for interlaying a conductive element and a method for manufacturing the same, wherein a space for interlaying a conductive element is formed on a circuit board by two-steps of hole-forming process. Hence, the conductive element can be interposed on the circuit board directly without using additional mounting terminal modules, so the assembly process can be simplified. 
         [0019]    To achieve this object, another aspect of the present invention is to provide a circuit board for interlaying a conductive element, which comprises: a first surface; a second surface corresponding to the first surface; a first circuit layer disposed on the first surface, wherein the first circuit layer comprises plural conductive pads; and a second circuit layer disposed on the second surface, wherein the second circuit layer comprises a metal contacting pad and a terminal pad, a cavity is formed in the terminal pad and extend to the first circuit layer, a metal layer is disposed on a surface of an inner wall of the cavity, the metal layer electrically connects to the first circuit layer and the terminal pads, and an opening for a conductive element interlaid therein is formed in the metal layer. 
         [0020]    A further another aspect of the present invention is to provide a method for manufacturing a circuit board for interlaying a conductive element, which comprises the following steps: providing a circuit board with a first surface and a second surface corresponding to the first surface, wherein a first circuit layer is disposed on the first surface, a second circuit layer is disposed on the second surface, the first circuit layer comprises plural conductive pads, and the second circuit layer comprises a metal contacting pad and a terminal pad; forming a cavity in the terminal pad of the circuit board, wherein the cavity extends to the first circuit layer; depositing a metal in the cavity; and forming an opening in the metal to form a metal layer which covers a surface of an inner wall of the cavity, wherein the opening is used for a conductive element interlaid therein. 
         [0021]    The aforementioned connection interface can be applied to various specifications such as peripheral component interconnection bus (PCI), industry standard architecture (ISA), Universal Serial Bus (USB) or equivalent connection interfaces. Preferably, the aforementioned connection interface is applied to USB 3.0. 
         [0022]    According to the present invention, a space for interlaying a conductive element can be defined on a circuit board. Hence, the conductive element can be mounted in this space without using additional mounting terminal modules, and thus the assembly process can be further simplified. 
         [0023]    Other objects, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0024]      FIG. 1A  to  FIG. 1D  are perspective views showing a process for manufacturing a circuit board for interlaying a conductive element according to Embodiment 1 of the present invention; 
           [0025]      FIG. 1D  to  FIG. 1I  are perspective views showing a process for manufacturing an electrical device with a connection interface according to Embodiment 2 of the present invention; 
           [0026]      FIG. 2  is a perspective view of an electrical device with a connection interface according to Embodiment 3 of the present invention; 
           [0027]      FIG. 3  is a perspective view of an electrical device with a connection interface according to Embodiment 4 of the present invention; 
           [0028]      FIG. 4  is a perspective view of an electrical device with a connection interface according to Embodiment 5 of the present invention; 
           [0029]      FIG. 5  is a perspective view of an electrical device with a connection interface according to Embodiment 6 of the present invention; and 
           [0030]      FIG. 6  is a perspective view of an electrical device with a connection interface according to Embodiment 7 of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0031]    The present invention has been described in an illustrative manner, and it is to be understood that the terminology used is intended to be in the nature of description rather than of limitation. Many modifications and variations of the present invention are possible in light of the above teachings. Therefore, it is to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described. 
         [0032]    In the following embodiments of the present invention, the figures are simplified perspective views. However, only the elements relate to the present invention are shown in these figures. These shown embodiments are not actual performance aspects. The numbers, the shapes and the sizes of the shown elements are only one selective design, and they may be more complicated. 
       Embodiment 1 
       [0033]      FIG. 1A  to  FIG. 1D  are perspective views showing a process for manufacturing a circuit board for interlaying a conductive element of the present embodiment. 
         [0034]    As shown in  FIG. 1A , a circuit board  1  is provided. The circuit board  1  has a first surface  10   a  and a second surface  10   b  corresponding to the first surface  10   a.  A first circuit layer  11  is disposed on the first surface  10   a,  a second circuit layer  12  is disposed on the second surface  10   b,  the first circuit layer  11  comprises plural conductive pads  13 , and the second circuit layer  12  comprises a metal contacting pad  14  and a terminal pad  16 . The method for manufacturing the circuit board  1  is not particularly limited, and any conventional method known in the art can be used in the present embodiment. For example, the circuit board  1  can be formed by using a substrate with two Cu films formed on two surface of the substrate, and followed by patterning the Cu films with a lithography process to form the first circuit layer  11  and the second circuit layer  12 . 
         [0035]    Next, as shown in  FIG. 1B , a cavity  160  is formed in the terminal pad  16  of the circuit board  1 , wherein the cavity  160  extends to the first circuit layer  11 . The method for forming the cavity  160  is not particularly limited. For example, the cavity  160  can be formed by a laser drilling process. 
         [0036]    As shown in  FIG. 1C , a metal  161 ′ is deposited in the cavity  160 . In this step, other portions or elements except for the region exposed from the cavity  160  can be protected by a resisting layer, and then an electroless plating process or an electroplating process is performed to form the metal  161 ′ in the cavity  160 . 
         [0037]    Then, as shown in  FIG. 1D , an opening  162  is formed in the metal  161 ′ to form a metal layer  161 , which covers a surface of an inner wall of the cavity  160 . Herein, the opening  162  is used for a conductive element (not shown in the figure) interlaid therein. In the process for forming the opening  162 , other portions or elements except for the region for forming the opening  162  can be protected by a resisting layer, and then an etching process is performed on the region which is not protected by the resisting layer to form the opening  162 . Alternatively, the opening  162  may also be formed with a laser drilling process. 
         [0038]    After the aforementioned process, the present embodiment provides a circuit board for interlaying a conductive element, which comprises: a first surface  10   a;  a second surface  10   b  corresponding to the first surface  10   a;  a first circuit layer  11  disposed on the first surface  10   a,  wherein the first circuit layer  11  comprises plural conductive pads  13 ; and a second circuit layer  12  disposed on the second surface  10   b,  wherein the second circuit layer  12  comprises a metal contacting pad  14  and a terminal pad  16 , a cavity  160  is formed in the terminal pad  16  and extend to the first circuit layer  11 , a metal layer  161  is disposed on a surface of an inner wall of the cavity  160 , the metal layer  161  electrically connects to the first circuit layer  11  and the terminal pads  16 , and an opening  162  for a conductive element interlaid therein is formed in the metal layer  161 . 
       Embodiment 2 
       [0039]      FIG. 1D  to  FIG. 1I  are perspective views showing a process for manufacturing an electrical device with a connection interface of the present embodiment. 
         [0040]    As shown in  FIG. 1D , a circuit board  1  is provided. The circuit board  1  has a first surface  10   a  and a second surface  10   b  corresponding to the first surface  10   a.  A first circuit layer  11  is disposed on the first surface  10   a,  a second circuit layer  12  is disposed on the second surface  10   b,  the first circuit layer  11  comprises plural conductive pads  13 , the second circuit layer  12  comprises a metal contacting pad  14  and a terminal pad  16 , a cavity  160  is formed in the terminal pad  16  and extends to the first circuit layer  11 , a metal layer  161  is disposed in the cavity  160 , the metal layer  161  electrically connects to the first circuit layer  11  and the terminal pads  16 , and an opening  162  is formed in the metal layer  161 . 
         [0041]    Next, as shown in  FIG. 1E , adhesive films  32  are formed between the semiconductor chips  2  and the first surface  10   a  of the circuit board  1  to mount the semiconductor chips  2  on the first surface  10   a  of the circuit board  1 . Herein the semiconductor chips  2  have plural electrode pads  23 . Then, as shown in  FIG. 1F , the electrode pads  23  electrically connect to the conductive pads  13  of the first circuit layer  11  respectively via wire bonds  33 . A molding process is performed to form a molding layer  35  to protect the semiconductor chips  2 , as shown in  FIG. 1G . The example of the material of the molding layer  35  can be epoxy resin. 
         [0042]    As shown in  FIG. 1H  and  FIG. 1I , a conductive element holder  5  is used to carry a conductive element  4  with a plug  46 . The conductive element holder  5  can align the plug  46  of the conductive element  4  with the opening  162  of the circuit board  1 , and then the plug  46  can be interlaid into the opening  162  exactly. Herein, the conductive element holder  5  may carry plural conductive elements  4 , so plural conductive elements  4  can be interlaid into plural openings  162  of the circuit board  1  at the same time, when there are two or more opening  162  formed on the circuit board  1 . According to the aforementioned illustration, it can be understand that the relation between the conductive element  4  and the opening  162  is like the relation between a bolt and a bolt hole. 
         [0043]    After the aforementioned process, the present embodiment provides an electrical device with a connection interface, which comprises: a circuit board  1  with a first surface  10   a  and a second surface  10   b  corresponding to the first surface  10   a,  wherein a first circuit layer  11  is disposed on the first surface  10   a,  a second circuit layer  12  is disposed on the second surface  10   b,  the first circuit layer  11  comprises plural conductive pads  13 , the second circuit layer  12  comprises a metal contacting pad  14  and a terminal pad  16 , a cavity  160  is formed in the terminal pad  16  and extends to the first circuit layer  11 , a metal layer  161  is disposed in the cavity  160 , an opening  162  is formed in the metal layer  161 , and the metal layer  161  electrically connects to the first circuit layer  11  and the terminal pads  16 ; a semiconductor chip  2  disposed on the first surface  10   a  and having plural electrode pads  23 , wherein the electrode pads  23  of the semiconductor chip  2  electrically connect to the conductive pads  13  of the first circuit layer  11  respectively; a conductive element  4  with a plug  46  interlaid into the opening  162 ; and an adhesive film  32  disposed between the semiconductor chip  2  and the first surface  10   a  of the circuit board  1 . 
       Embodiments 3-7 
       [0044]      FIG. 2  to  FIG. 6  are perspective views of an electrical device with a connection interface of Embodiments to Embodiment 7 respectively. 
         [0045]    As shown in  FIG. 2 , the structure of the electrical device with a connection interface of Embodiment 3 is similar to that of Embodiment 2, except that the bottom of the plug  46  of the conductive element  4  is firstly coated with a contacting layer  64 , and then the plug  46  of the conductive elements  4  is aligned with and interlaid into the opening  162  of the circuit board  1 . In addition, the opening  162  of the circuit board  1  does not extend to the first circuit layer  11 , i.e. the first circuit layer  11  is not exposed from the opening  162 . Hence, compared to the electrical device with a connection interface of Embodiment 2, the electrical device with a connection interface of Embodiment 3 further comprises a contacting layer  64 , which is disposed between the plug  46  of the conductive element  4  and the metal layer  161 . 
         [0046]    As shown in  FIG. 3 , the structure of the electrical device with a connection interface of Embodiment 4 is similar to that of Embodiment 3, except that the opening  162  of the circuit board  1  extends to the first circuit layer  11 , i.e. the first circuit layer  11  is exposed from the opening  162 . Hence, the contacting layer  64  is disposed between the plug  46  of the conductive element  4  and the first circuit layer  11 . In addition, a semiconductor chip  2  is disposed on a surface of the first circuit layer  11 , but not on the region that no circuit is formed thereon. 
         [0047]    As shown in  FIG. 4 , the structure of the electrical device with a connection interface of Embodiment 5 is similar to that of Embodiment 2, except that the opening  162  of the circuit board  1  extends to the first circuit layer  11 , i.e. the first circuit layer  11  is exposed from the opening  162 . Hence, the contacting layer  64  is disposed between the plug  46  of the conductive element  4  and the first circuit layer  11 . In addition, the conductive element  4  comprises a curved buffer structure  41  to absorb pressure or stress of pressing. 
         [0048]    As shown in  FIG. 5 , the structure of the electrical device with a connection interface of Embodiment 6 is similar to that of Embodiment 5, except that the contacting layer  64  is disposed between the plug  46  of the conductive element  4  and the first circuit layer  11  and the metal layer  161 . In addition, the conductive element  4  also comprises a bent buffer structure  41  to absorb pressure or stress of pressing. 
         [0049]    As shown in  FIG. 6 , the structure of the electrical device with a connection interface of Embodiment 7 is similar to that of Embodiment 3, except that an insulating layer  17  is formed on the first surface  10   a  and the second surface  10   b  of the circuit board  1  before the semiconductor chip  2  is disposed thereon. The insulating layer  17  covers the first circuit layer  11  and the second circuit layer  12 . In addition, the insulating layer  17  has plural contacting windows  171  to expose the conductive pads  13 , the metal contacting pad  14  and the terminal pad  16 . 
         [0050]    Although the present invention has been explained in relation to its preferred embodiment, it is to be understood that many other possible modifications and variations can be made without departing from the spirit and scope of the invention as hereinafter claimed.