Abstract:
Disclosed herein is a structure of an opto-electronic package having a Si-substrate. Si-substrates are manufactured in batch utilizing micro-electromechanical processes or semiconductor processes, so that these Si-substrates are made with great precision and full of varieties. Based on the material characteristics of the Si-substrate, and the configuration of the components, such as the connecters, opto-electronic devices, depressions, solder bumps, etc., the present invention can improve the optical effect, the heat dissipating effect, and the reliability of the structure of opto-electronic package, and simplifies the complexity of the structure of opto-electronic package.

Description:
BACKGROUND OF THE INVENTION  
       [0001]    1. Field of the Invention 
         [0002]    The present invention generally relates to the field of opto-electronic package structures, and more particularly, to an opto-electronic package structure formed by the micro-electromechanical processes or the semiconductor processes. 
         [0003]    2. Description of the Prior Art 
         [0004]    In recent years, a new application field of high illumination light emitting diodes (LEDs) has been developed. Different from a common incandescent light, a cold illumination LED has the advantages of low power consumption, long device lifetime, no idling time, and quick response speed. In addition, since the LED also has the advantages of small size, vibration resistance, suitability for mass production, and ease of fabrication as a tiny device or an array device, it has been widely applied in display apparatuses and indicating lamps used in information, communication, and consumer electronic products. The LEDs are not only utilized in outdoor traffic signal lamps or various outdoor displays, but are also very important components in the automotive industry. Furthermore, the LEDs work well in portable products, such as cellular phones and as backlights of personal data assistants. These LEDs have become necessary key components in the highly popular liquid crystal displays because they are the best choice when selecting the light source of the backlight module. 
         [0005]    Please refer to  FIG. 1  and  FIG. 2 .  FIG. 1  is a schematic top view diagram showing a prior art surface mount device (SMD) LED package structure  10 , and  FIG. 2  is a cross section diagram illustrating the prior art SMD LED package structure  10  along  1 - 1 ′ line shown in  FIG. 1 . As shown in  FIG. 1  and  FIG. 2 , an SMD LED package structure  10  comprises a cup-structure substrate  12 , a lead frame  14 , an opto-electronic device  16 , conducting wires  18  and  20 , and a sealant  22 . As a semiconductor device comprising a positive electrode and a negative electrode (not shown), the opto-electronic device  16  is illuminated by receiving power from an external voltage source and connected to the lead frame  14  by the conducting wires  18  and  20 . Situated in the cup-structure substrate  12 , the lead frame  14  is extended to the outer surface of the cup-structure substrate  12 , which will be electrically connected to a printed circuit board (PCB)  24 . 
         [0006]    In order to construct the prior art LED package  10 , the cup-structure substrate  12  should be completed first, and then the sealant  22  covers the opto-electronic device  16  by means of molding or sealant injection. After the construction of the prior art LED package  10  is completed, at least a surface mounting process is performed to mount the LED packages  10  on the PCB  24  individually. As a result, it is almost impossible to produce the LED packages  10  in batch, and the manufacturing process of the electronic products is too complicated and tedious. As applied in a LED package  10  with high power, the cup-structure substrate  12  of the opto-electronic device  16  is unavoidably overheated, which may eventually result in a reduction of light intensity or failure of the entire device. Due to the significantly large volume of the single LED package  10  and the heat radiating demand required by a LED package  10  with high power, the designed size and the heat dissipating efficiency of the whole LED package  10  are greatly limited. 
       SUMMARY OF THE INVENTION  
       [0007]    It is the primary object of the present invention to provide an opto-electronic package structure having a Si-substrate. Accordingly, the present invention can improve the optical effect, the heat dissipating effect, and the reliability of the opto-electronic package structure, the opto-electronic package structure can be manufactured in batch, and the complexity of the opto-electronic package structure can be simplified. 
         [0008]    According to the claimed invention, an opto-electronic package structure having Si-substrates is disclosed. The opto-electronic package structure includes a silicon wafer. The silicon wafer defines a plurality of Si-substrates therein. Each of the Si-substrates includes a plurality of connecters and at least an opto-electronic device electrically connected to the connecters. The Si-substrates include at least two different outline shapes. 
         [0009]    Since the Si-substrates can be produced in a batch system utilizing micro-electromechanical processes or semiconductor processes, these Si-substrates are made with great precision and full of varieties. According to the characteristics of Si-substrate and the arrangement of the components, such as the connecters, the opto-electronic device, the cup-structure and the flip-chip bump on Si-substrate, the present invention can simplify the complexity of the components in the opto-electronic package structure, and increase the optical effect, the heat-dissipating effect and the packaging reliability of the opto-electronic package structure. 
         [0010]    These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0011]      FIG. 1  is a schematic top view diagram showing a prior art surface mount device (SMD) LED package structure. 
           [0012]      FIG. 2  is a cross section diagram illustrating the prior art SMD LED package structure along  1 - 1 ′ line shown in  FIG. 1 . 
           [0013]      FIG. 3  is a cross-sectional schematic diagram illustrating an opto-electronic package structure having Si-substrates according to a first preferred embodiment of the present invention. 
           [0014]      FIG. 4  is a cross-sectional schematic diagram illustrating an opto-electronic package structure having Si-substrates according to a second preferred embodiment of the present invention. 
           [0015]      FIG. 5  is a cross-sectional schematic diagram illustrating an opto-electronic package structure having Si-substrates according to a third preferred embodiment of the present invention. 
           [0016]      FIG. 6  is a cross-sectional schematic diagram illustrating an opto-electronic package structure having Si-substrates according to a fourth preferred embodiment of the present invention. 
           [0017]      FIG. 7  is a cross-sectional schematic diagram illustrating an opto-electronic package structure having Si-substrates according to a fifth preferred embodiment of the present invention. 
           [0018]      FIG. 8  is a cross-sectional schematic diagram illustrating an opto-electronic package structure having Si-substrates according to a sixth preferred embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION  
       [0019]    Please refer to  FIG. 3 .  FIG. 3  is a cross-sectional schematic diagram illustrating an opto-electronic package structure having Si-substrates according to a first preferred embodiment of the present invention. As shown in  FIG. 3 , an opto-electronic package structure  100  includes a silicon wafer  101 , and at least two Si-substrates  102 ,  202  are defined in the silicon wafer  101  according to the product design. The Si-substrate  102  includes a plurality of connecters  104  and at least an opto-electronic device  106  electrically connected to the connecters  104  through bumps. The Si-substrate  202  includes a plurality of connecters  204  and at least an opto-electronic device  206  electrically connected to the connecters  204  through bumps. Each of the connecters  104 ,  204  can be a flat metal layer having large area or a metal circuit layer having circuits therein, and the positive electrode of each opto-electronic device  206  will not short with the negative electrode through the connecters  104 ,  204 . As shown in the figure, the Si-substrate  102  includes a cup-structure  108 , and the Si-substrate  202  includes a cup-structure  208 . Because the Si-substrates  102 ,  202  can be manufactured in the silicon wafer  101  by utilizing the micro-electromechanical processes or the semiconductor processes, the cup-structure  108  and the cup-structure  208 , which have different shapes, can be produced on the top surface of one silicon wafer  101  in the meantime. According to this embodiment, the cup-structure  108  includes an inclined sidewall  108   a , and the cup-structure  208  includes a vertical sidewall  108   b.    
         [0020]    Other shapes of the cup-structures can be formed in the present invention according to different etching masks and different etching methods. Please refer to  FIG. 4 .  FIG. 4  is a cross-sectional schematic diagram illustrating an opto-electronic package structure having Si-substrates according to a second preferred embodiment of the present invention. As shown in  FIG. 4 , an opto-electronic package structure  110  includes a silicon wafer  111 , and at least two Si-substrates  112 ,  212  are defined in the silicon wafer  111 . The Si-substrate  112  includes a plurality of connecters  114 , a cup-structure  118 , and at least an opto-electronic device  116  electrically connected to the connecters  114  through bumps. The Si-substrate  212  includes a plurality of connecters  214 , a cup-structure  218 , and at least an opto-electronic device  216  electrically connected to the connecters  214  through bumps. As shown in this embodiment, the cup-structure  118  includes an inclined sidewall  118   a , and the cup-structure  218  includes an arc sidewall  118   c.    
         [0021]    Please refer to  FIG. 5 .  FIG. 5  is a cross-sectional schematic diagram illustrating an opto-electronic package structure having Si-substrates according to a third preferred embodiment of the present invention. As shown in  FIG. 5 , an opto-electronic package structure  120  includes a silicon wafer  121 , and at least two Si-substrates  122 ,  222  are defined in the silicon wafer  121 . The Si-substrate  122  includes a plurality of connecters  124 , a cup-structure  128 , and at least an opto-electronic device  126  electrically connected to the connecters  124  through bumps. The Si-substrate  222  includes a plurality of connecters  224 , a cup-structure  228 , and at least an opto-electronic device  226  electrically connected to the connecters  224  through bumps. As shown in this embodiment, the cup-structure  128  includes a vertical sidewall  128   b , and the cup-structure  228  includes an arc sidewall  128   c.    
         [0022]    Please refer to  FIG. 6 .  FIG. 6  is a cross-sectional schematic diagram illustrating an opto-electronic package structure having Si-substrates according to a fourth preferred embodiment of the present invention. As shown in  FIG. 6 , an opto-electronic package structure  130  includes a silicon wafer  131 . At least three Si-substrates  132 ,  232 ,  332  are defined in the silicon wafer  131 . The Si-substrate  132  includes a plurality of connecters  134 , a cup-structure  138 , and at least an opto-electronic device  136  electrically connected to the connecters  134  through bumps. The Si-substrate  232  includes a plurality of connecters  234 , a cup-structure  238 , and at least an opto-electronic device  236  electrically connected to the connecters  234  through bumps. The Si-substrate  332  includes a plurality of connecters  334 , a cup-structure  338 , and at least an opto-electronic device  336  electrically connected to the connecters  334  through bumps. As shown in this embodiment, the cup-structure  138  includes an inclined sidewall  138   a , the cup-structure  338  includes a vertical sidewall  138   b , and the cup-structure  238  includes an arc sidewall  138   c . 
         [0023]    The different shapes of the cup-structures are set for matching the different opto-electronic devices used in the opto-electronic package structures. For example, the above-mentioned opto-electronic devices can be red LEDs, blue LEDs, green LEDs, etc. so as to bring different optical effects. 
         [0024]    In another aspect, the shapes and the positions of the cup-structures can be adjusted according to the radiation of the opto-electronic devices and the required optical effect of the opto-electronic package structure. Please refer to  FIG. 7 .  FIG. 7  is a cross-sectional schematic diagram illustrating an opto-electronic package structure having Si-substrates according to a fifth preferred embodiment of the present invention. As shown in  FIG. 7 , an opto-electronic package structure  140  includes a silicon wafer  141 , and at least two Si-substrates  142 ,  242  are defined in the silicon wafer  141 . As shown in this embodiment, the Si-substrate  142  includes a red LED component  146   a , a blue LED component  146   b , a green LED component  146   c , a cup-structure  148   a  containing the red LED component  146   a , a cup-structure  148   b  containing the blue LED component  146   b , a cup-structure  148   c  containing the green LED component  146   c , and a plurality of connecters  144  electrically connected to the LED components  146   a ,  146   b , and  146   c . The Si-substrate  242  includes a red LED component  246   a , a blue LED component  246   b , a green LED component  246   c , a cup-structure  248   a  containing the red LED component  246   a , a cup-structure  248   b  containing the blue LED component  246   b , a cup-structure  248   c  containing the green LED component  246   c , and a plurality of connecters  244  electrically connected to the LED components  246   a ,  246   b , and  246   c.    
         [0025]    In the Si-substrate  142 , the cup-structure  148   a  has a first depth  310 , the cup-structure  148   b  and the cup-structure  148   c  have a second depth  320 , and the first depth  310  is larger than the second depth  320 . In the Si-substrate  242 , the cup-structure  248   a  has a first depth  312 , the cup-structure  248   b  has a second depth  322 , and the cup-structure  248   c  has a third depth  332 . The first depth  312  is larger than the second depth  322 , and the second depth  322  is larger than the third depth  332 . Accordingly, the Si-substrates  142 ,  242  can match the optical characteristic of the LED components  146   a ,  146   b ,  146   c ,  246   a ,  246   b , and  246   c.    
         [0026]    More opto-electronic package structures, which have different effects, can be integrated on one silicon wafer so as to increase the varieties and values of products. Please refer to  FIG. 8 .  FIG. 8  is a cross-sectional schematic diagram illustrating an opto-electronic package structure having Si-substrates according to a sixth preferred embodiment of the present invention. As shown in  FIG. 8 , an opto-electronic package structure  150  includes silicon wafer  151 , and at least two Si-substrates  152 ,  252  are defined in the silicon wafer  151 . The Si-substrate  152  includes a plurality of connecters  154  and at least an opto-electronic device  156  electrically connected to the connecters  154 . The Si-substrate  252  includes a plurality of connecters  254  and at least an opto-electronic device  256  electrically connected to the connecters  254 . Accordingly, the Si-substrate  152  includes electric-conducting holes  312 , and each connecter  154  on this Si-substrate  152  extends from the top surface of the Si-substrate  152  to the bottom surface of the Si-substrate  152  through at least one of the electric-conducting holes  312 . On other hand, the opto-electronic device  256  is located on the top surface of the Si-substrate  252 , and the top surface of the Si-substrate  252  is a substantially flat surface. The bottom surface of the Si-substrate  252  can be a fin structure so as to increase the heat-dissipating efficiency. 
         [0027]    After all components of the above-mentioned opto-electronic package structure are completed, the Si-substrates can be separated from each other by means of a dicing process. As a result, the opto-electronic package structure is divided into a plurality of individual package structures, and each individual package structure can be thereafter electrically connected to the corresponding printed circuit board through the connecters of each Si-substrate. 
         [0028]    Since the opto-electronic device is packaged with the Si-substrate in the present invention, and the Si-substrates can be manufactured by utilizing the micro-electromechanical processes or the semiconductor processes that are well-developed technologies, a variety of Si-substrates, which have different outline shapes, can be produced in a batch system. Thus, the opto-electronic package structure can be diversified and have fine structure. 
         [0029]    Because the present invention chooses the Si-substrate to be the base of the opto-electronic package structure, and the heat transfer coefficient of silicon material is quite large, the heat-dissipating effect of the opto-electronic package structure can be increased. In addition, since silicon and an LED component are both made from semiconductor materials, the coefficient of thermal expansion (CTE) of silicon is approximate to the CTE of the LED. Therefore, using silicon to form the packaging substrate can increase the reliability of the produced opto-electronic package structure. 
         [0030]    Furthermore, the opto-electronic package structure having the Si-substrate can be made in a batch system utilizing micro-electromechanical processes or semiconductor processes. According to the characteristics of Si-substrate and the arrangement of the components, such as the connecters, the opto-electronic device, the cup-structure and the flip-chip bump on Si-substrate, the present invention can simplify the complexity of the components in the opto-electronic package structure, and increase the optical effect, the heat-dissipating effect and the packaging reliability of the opto-electronic package structure. 
         [0031]    Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.