Abstract:
A fingerprint sensor package includes a substrate, a fingerprint sensor chip, and a flexible printed circuit board (FPC). The substrate includes a first portion and a second portion. A line layer is disposed on the first portion. The fingerprint sensor chip is disposed on the substrate. The fingerprint sensor chip is electrically connected to the FPC by the line layer. The package is simple, reliable, and easy for manufacturing process, reducing materials and processing costs.

Description:
BACKGROUND 
     1. Technical Field 
       [0001]    The subject matter herein generally relates to a field of data security, and particularly to package of a fingerprint sensor and methods for fabricating the package of fingerprint sensor. 
       2. Description of Related Art 
       [0002]    A fingerprint identification chip improves the security of the terminal products such as the fingerprint chip applied in smart phone, tablet PC etc. The potential limitations and disadvantages of conventional fingerprint identification chips comprises: (a) The fingerprint identification chip is etched to form a conductive layer and is connected to a substrate by combination lines, which is a complicated and expensive process; (b) There is a coating layer on the finger contact portion, which is easily scratched or contaminated to cause failure of recognition; (c) The combination lines connected with the chip and the substrate expose portions between the chip and the substrate. The chip, the line layer and the substrate are required to package before bonding with adjacent layers to avoid electrical connection problems. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0003]    Implementations of the present technology will now be described with reference to the attached figures. 
           [0004]      FIG. 1  is an exemplary embodiment of a fingerprint sensor package. 
           [0005]      FIG. 2  is an exemplary embodiment of a substrate in the fingerprint sensor package of  FIG. 1 . 
           [0006]      FIG. 3  is the substrate in  FIG. 2  as seen from another direction. 
           [0007]      FIG. 4  is an exemplary embodiment of a fingerprint sensor formed with a block in the fingerprint sensor package of  FIG. 1 . 
           [0008]      FIG. 5  is an exemplary embodiment of a flexible printed circuit. 
           [0009]      FIG. 6  is an exemplary embodiment of the combined fingerprint sensor chip and the substrate. 
           [0010]      FIG. 7  is a flow chart of a manufacturing process for a fingerprint sensor package. 
       
    
    
     DETAILED DESCRIPTION 
       [0011]    It will be appreciated that for simplicity and clarity of illustration, where appropriate, reference numerals have been repeated among the different figures to indicate corresponding or analogous elements. In addition, numerous specific details are set forth in order to provide a thorough understanding of the embodiments described herein. However, it will be understood by those of ordinary skill in the art that the embodiments described herein can be practiced without these specific details. In other instances, methods, procedures, and components have not been described in detail so as not to obscure the related relevant feature being described. Also, the description is not to be considered as limiting the scope of the embodiments described herein. The drawings are not necessarily to scale and the proportions of certain parts have been exaggerated to better illustrate details and features of the present disclosure. 
         [0012]    The disclosure is illustrated by way of example and not by way of limitation in the figures of the accompanying drawings in which like reference numerals indicate the same or similar elements. It should be noted that references to “an” or “one” embodiment in this disclosure are not necessarily to the same embodiment, and such references can mean “at least one.” 
         [0013]      FIG. 1  shows a fingerprint sensor package. The fingerprint sensor comprises a substrate  1 , a fingerprint sensor chip  2 , and a flexible printed circuit board (FPC)  3 . The fingerprint sensor chip  2  is electrically connected to the FPC  3  through a line layer  13  of the substrate  1 . 
         [0014]      FIG. 2  shows a substrate  1 . The substrate  1  comprises a first portion  11  and a second portion  12 . The length and thickness of the first portion  11  can be less than the length and thickness of the second portion  12 . The first portion  11  has a first surface  110 , the second portion  12  has a second surface  120 , and the first surface  110  is parallel to the second surface  120 .  FIG. 3  shows a view toward the first surface  110  and the second surface  120  of the substrate  1 . A line layer  13  is distributed on the first surface  110  of the first portion  11 , the line layer  13  does not extend out from the first portion around. The substrate  1  is made of reinforced glass, sapphire, or ceramic material. 
         [0015]      FIG. 4  shows a fingerprint sensor chip  2  including a chip body  21  and a block  22 . The chip body  21  has a third surface  210 . In the exemplary embodiment, the chip body  21  is rectangular. The layout of combination lines and electrical connections as in traditional fingerprint sensors are less of a concern since the line layer  13  of the exemplary embodiment is formed on the first portion  11  of the substrate  1 . The chip body  21  can be any shape without reference to or being influence by the line layer  13 . The block  22  is placed on one side of the third surface  210 . The block  22  can be a soldering ball or other shapes, the block  22  can be made of a metal or tin alloy which is conductive. 
         [0016]      FIG. 5  shows an FPC  3  including a body  31 , a connector  32 , and a plurality of SMD components. The connector  32  and the SMD components are soldered on the body  31 , and one end of the body  31  forms a soldering point  33 . 
         [0017]      FIG. 6  shows the fingerprint sensor chip  2  assembled on the substrate  1 . The block  22  of the fingerprint sensor chip  2  extends out from the second surface  120  of the second portion  12  relative to the first surface  110  of the first portion  11 . The fingerprint sensor chip  2  is electrically connected to the line layer  13  through the block  22 . The block is fixed on the first portion  11  by adhesive  4  such as epoxy resin, and part of the third surface  210  is fixed on the second portion  12  by the adhesive  4 . 
         [0018]    Referring to  FIG. 1 , the soldering point  33  of the FPC  3  is soldered with the first portion  11  and the line layer  13 . The fingerprint sensor chip  2  is in contact with the line layer  13  by the block  22 , and the fingerprint sensor chip  2  is electrically connected to the FPC  3  through the line layer  13 . 
         [0019]      FIG. 7  shows a flow chart of a method for manufacturing a fingerprint sensor package. The method described below can be carried out using the configurations illustrated in  FIGS. 1-6 . 
         [0020]    In S 2 : a fingerprint sensor chip  2  is manufactured, the fingerprint sensor chip  2  has a chip body  21 , and a block  22  is made on the chip body  21 , as shown in  FIG. 4 . 
         [0021]    In S 4 : a substrate  1  is manufactured, and the substrate  1  is cut into a first portion  11  and a second portion  12 . A line layer  13  is distributed on a first surface  110  of the first portion  11 , as shown in  FIG. 2  and  FIG. 3 . 
         [0022]    In S 6 : an FPC  3  is manufactured. The FPC  3  has a body  31 , a connector  32 , and a plurality of SMD components soldered on the body  31 , as shown in  FIG. 5 . 
         [0023]    In S 8 : Adhesive  4  is used to combine the fingerprint sensor chip  2  and the second portion  12  of the substrate  1 . The block  22  extends out from the second portion  12  and is fixed with the first portion  11  by the adhesive  4  to be electrically connected to the line layer  13 , as shown in  FIG. 6 . 
         [0024]    In S 10 : the FPC  3  is soldered on the first portion  11  to form a solder point  33  electrically connected to the line layer  13 . 
         [0025]    By the method described in  FIG. 7 , the FPC  3  is electrically connected to the line layer  13  by the solder point  33  and the fingerprint sensor chip  2  is electrically connected to the line layer  13  by the block  22 . Thereby, the fingerprint sensor chip  2  and the FPC  3  are electrically connected. 
         [0026]    In an exemplary embodiment, the line layer  13  is positioned on the substrate  1  and the fingerprint sensor chip  2  is electrically connected to the line layer  13  by the block  22 . Thus the etching for the fingerprint sensor chip  2  is omitted. The line layer  13  is placed on the substrate  1  of reinforced glass and the surface of the fingerprint sensor chip  2  is directly fixed on the substrate  1  by adhesive  4  without packaging. This decreases the thickness of the fingerprint sensor chip  2 . The fingerprint sensor uses the reinforced glass instead of coating to avoid scratching, contaminations, or chromatism. The structure of the fingerprint sensor according to an exemplary embodiment of the disclosure is simple and the manufacturing method is fast and lower cost. The fingerprint sensor chip receives and detects users&#39; fingers on the substrate made of glass, and the fingerprint sensor chip is electrically connected to a conductor by chip circuit to process the electrical signals output by the conductor. 
         [0027]    Although the features and elements of the present disclosure are described as embodiments in particular combinations, each feature or element can be used alone or in other various combinations, within the principles of the present disclosure to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.