Abstract:
A flexible electronic module is provided, including a flexible substrate having a supporting portion, a body portion, and a connection portion, wherein the supporting portion is connected with the body portion via the connection portion; a first trench formed between the supporting portion and the body portion; an electronic component disposed over a portion of the supporting portion; and a conductive line disposed over the supporting portion, the connection portion, and the body portion for connecting the electronic component.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    The present application is based on, and claims priority from Taiwan Application Serial Number 102148380, filed on Dec. 26, 2013, the disclosure of which is hereby incorporated by reference herein in its entirety. 
       TECHNICAL FIELD 
       [0002]    The disclosure relates to electronic devices. Particularly, the disclosure relates to a flexible electronic module with improved reliability and a longer lifespan. 
       BACKGROUND 
       [0003]    Flexible electronic devices have been widely adopted in various applications such as biological experiments, medical treatments, and consumer electronic devices. Common flexible electronic devices are, for example, flexible display devices, skin-like electronic sensors, and stretchable/deformable neural interface systems. 
         [0004]    However, a sensing electronic device in the flexible electronic devices, such as a sensing chip, is usually composed of inflexible materials such as semiconductor materials. Therefore, as the number of uses or the operation frequency increases, the inflexible electronic devices made of inflexible materials may thus show some undesired problems such as peeling or delamination of the sensing electronic device. As a result, the reliability and the lifetime of the flexible electronic device may be thus affected. 
       SUMMARY 
       [0005]    An exemplary flexible electronic module is provided, comprising a flexible substrate, a first trench, an electronic device, and a conductive line. The flexible substrate comprises a supporting portion, a body portion, and a connection portion. The supporting portion is connected to the body portion through the connection portion. The first trench is formed between the supporting portion and the body portion. The electronic device is disposed over a portion of the supporting portion. The conductive line is disposed over the supporting portion, the connection portion, and the body portion for connecting the electronic device. 
         [0006]    Another exemplary flexible electronic module is provided, comprising a flexible substrate, a first trench, an electronic device, and a conductive line. The flexible substrate comprises a supporting portion, a body portion, a connection portion, and a line-routing portion. A surface of the body portion is lower than surfaces of the supporting portion, the connection portion, and the line-routing portion. The supporting portion is connected to the line-routing portion through the connection portion. The first trench is disposed between the supporting portion, the connection portion, and the line-routing portion. The electronic device is disposed over the supporting portion. The conductive line is disposed over the supporting portion, the connection portion, and the line-routing portion for connecting the electronic device. 
         [0007]    A detailed description is given in the following embodiments with reference to the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0008]    The present disclosure can be more fully understood by reading the subsequent detailed description and examples with references made to the accompanying drawings, wherein: 
           [0009]      FIG. 1  is a schematic top view showing a flexible electronic device according to an embodiment of the disclosure. 
           [0010]      FIG. 2  is a schematic cross-sectional view showing a portion of the flexible electronic device in  FIG. 1  along line  2 - 2  therein. 
           [0011]      FIG. 3  is a schematic cross-sectional view showing a flexible electronic device in  FIG. 2  being stretched by stress. 
           [0012]      FIG. 4  is a schematic perspective view showing a flexible substrate applicable in a flexible electronic module according to an embodiment of the disclosure. 
           [0013]      FIG. 5  is a schematic perspective view showing a flexible substrate applicable in a flexible electronic module according another embodiment of the disclosure. 
           [0014]      FIG. 6  is a schematic perspective view showing a flexible substrate applicable in a flexible electronic module according to yet another embodiment of the disclosure. 
           [0015]      FIG. 7  is a schematic perspective view showing a flexible substrate applicable in a flexible electronic module according to another embodiment of the disclosure. 
           [0016]      FIG. 8  is a schematic perspective view showing a flexible substrate applicable in a flexible electronic module according to yet another embodiment of the disclosure. 
           [0017]      FIG. 9  is a schematic perspective view showing a flexible substrate applicable in a flexible electronic module according to another embodiment of the disclosure. 
           [0018]      FIG. 10  is a schematic perspective view showing a flexible substrate applicable in a flexible electronic module according to yet another embodiment of the disclosure. 
           [0019]      FIG. 11  is a schematic perspective view showing a flexible substrate applicable in a flexible electronic module according to another embodiment of the disclosure. 
           [0020]      FIG. 12  is a schematic perspective view showing a flexible substrate applicable in a flexible electronic module according to yet another embodiment of the disclosure. 
           [0021]      FIG. 13  is a schematic perspective view showing a flexible substrate applicable in a flexible electronic module according to another embodiment of the disclosure. 
       
    
    
     DETAILED DESCRIPTION 
       [0022]    Below, exemplary embodiments will be described in detail with reference to accompanying drawings so as to be easily realized by a person having ordinary knowledge in the art. The inventive concept may be embodied in various forms without being limited to the exemplary embodiments set forth herein. Descriptions of well-known parts are omitted for clarity, and like reference numerals refer to like elements throughout. 
         [0023]      FIG. 1  and  FIG. 2  are schematic top and cross-sectional views showing an exemplary flexible electronic module  100 , respectively. The schematic cross-sectional view in  FIG. 2  shows a cross-sectional structure of a portion of the flexible electronic module  100  along line  2 - 2  in  FIG. 1 . 
         [0024]    As shown in  FIGS. 1-2 , the flexible electronic module  100  comprises a flexible substrate  102 , a trench  104 , an electronic device  106 , and a pair of conductive lines  108 . The trench  104  is formed on a portion of the flexible substrate  102  to thereby define a body portion  102   a  and a supporting portion  102   b  separated by the trench  104 . The supporting portion  102   b  is connected with the body portion  102   a  through a connection portion  102   c . In one embodiment, a surface of the body portion  102   a  is coplanar with a surface of the supporting portion  102   b . The trench  104  can be formed by combination of a lithography process and an etching process, or a laser cutting process (both not shown). In one embodiment, the flexible substrate  102  may comprise flexible or stretchable insulating materials such as rubber, polyurethanes, polysiloxane, polyolefin, or polychlorinated olefins. The conductive lines  108  may comprise conductive materials such as conductive polymers, amorphous metal alloys, graphene, or nano conductive lines. The conductive lines  108  may comprise flexible or inflexible conductive materials. Characteristics of the flexible conductive materials can be referred to in the thesis entitled “Compliant Silver Nanowire-Polymer Composite Electrodes for Bistable Large Strain Actuation”, Advanced Materials, vol. 24, pages 1321-1327 (2012), or the thesis entitled “Buckling of Aligned Carbon Nanotubes as Stretchable Conductors: A New Manufacturing Strategy”, Advanced Materials, vol. 24, issue 8, pages 1073-1077 (2012). 
         [0025]    As shown in  FIG. 1 , the body portion  102   a  surrounds the supporting portion  102   b , and an electronic device  106  is disposed over a portion of the supporting portion  102   b . In one embodiment, the electronic device  106  can be a sensing device such as a thermal-sensing device, a stress-sensing device, a light-sensing device, a humidity-sensing device, or a gas-sensing device, and may comprise inflexible materials such as semiconductor silicon therein. Alternatively, the electronic device  106  can be a sensing device such as a light-emitting device, a thermo-electrical device, or an electromagnetic device, and may comprise inflexible materials such as oxide or metal materials. In addition, a pair of conductive lines  108  are respectively disposed over different positions of the supporting portion  102   b  to connect different portions, for example a positive end and a negative end (both not shown) of the electronic device  106 . Moreover, the conductive lines  108  are disposed over a portion of the connection portion  102   c  and the body portion  102   a , respectively, to form electrical connections between the electronic device  106  and outer electronic devices or conductive lines (both not shown). In other embodiments, the conductive line  108  may be formed in other numbers, for example one or two conductive lines  108 , and is not limited to the pair of conductive lines  108  shown in  FIG. 1 . 
         [0026]    In  FIG. 2 , the trench  104  is formed with a depth d, and a ratio of the depth d to a thickness S of the flexible substrate  102  is between about 1:2 and 1:10. The trench  104  surrounds about 90-99% of a circumference of the supporting portion  102   b  to separate the body portion  102   a  with the supporting portion  102   b  of the flexible substrate  102 . Therefore, as shown in  FIG. 3 , while external stress (not shown) is applied to the flexible electronic module  100  to induce tensile deformation thereto, the supporting portion  102   b  may show an amount of tensile strain that is less than about 10%, may less than 5%, while the body portion  102   a  shows an amount of tensile strain that is about 20% to 60%. The amount of the tensile strain mentioned above is defined as [(a size of the portion prior to deformation−a size of the portion after deformation)/a size of the portion prior to deformation]*100%. 
         [0027]    Therefore, while the external stress is applied to the flexible substrate  102  shown in  FIGS. 1-3 , the supporting portion  102   b  can be taken as a region with lower tensile deformation when compared with the body portion  102   a  of the flexible substrate  102 , such that the electronic device  106  disposed over the supporting portion  102   b  is less affected by the tensile deformation induced by the external stress, thereby reducing undesired peeling or delaminating of the overlying electronic device  106  which may be caused by the stretched deformation of the supporting portion  102   b , and improving the reliability and lifetime of the electronic device  106 . 
         [0028]      FIG. 4  is a schematic perspective view showing a flexible substrate  102  applicable in the flexible electronic module  100  shown in  FIGS. 1-3 . As shown in  FIG. 4 , the portion of the flexible substrate  102  is a portion adjacent to the body portion  102   a  and comprises the body portion  102   a , the supporting portion  102   b , the connection portion  102   c , and the trench  104 . The configuration of this portion is similar with that shown in  FIGS. 1-3  and is not described here again for brevity. 
         [0029]    In addition, the shapes of the supporting portion  102   b  and the trench  104  in the flexible substrate  12  applicable in the flexible electronic module  100  shown in  FIGS. 1-4  are not limited to the circular shape shown in  FIGS. 1 and 4 . In other embodiments, the shapes of the supporting portion  102   b  and the trench  104  in the flexible substrate  102  can be, for example, other shapes including oval, and polygonal such as rectangular or hexagonal. 
         [0030]      FIG. 5  is a schematic perspective view showing another exemplary flexible substrate  102  applicable in the flexible electronic module  100  shown in  FIGS. 1-3 , comprising the supporting portion  102   b  and the trench  104  having an oval shape. In addition,  FIG. 6  is a schematic perspective view showing yet another exemplary flexible substrate  102  applicable in the flexible electronic module  100  shown in  FIGS. 1-3 , comprising the supporting portion  102   b  and the trench  104  having a hexagonal shape. Moreover,  FIG. 7  is a schematic perspective view showing another exemplary flexible substrate  102  applicable in the flexible electronic module  100  shown in  FIGS. 1-3 , comprising the supporting portion  102   b  and the trench  104  having a rectangular configuration. 
         [0031]      FIG. 8  is a schematic perspective view showing yet another flexible substrate  102  applicable in the flexible electronic module  100  shown in  FIGS. 1-3 . In one embodiment, the flexible substrate  102  shown in  FIG. 8  is similar to that shown in  FIG. 4 , and the difference therebetween is that a trench  120  is additionally disposed in the flexible substrate  102 . The trench  120  is disposed in a portion of the body portion  102   a  at a side adjacent to the connection portion  102   c , having a distance P to the connection portion  102   c  The distance P can be adjusted according to the needs of the design but is not a fixed distance. A ratio of a depth (not shown) of the trench  120  to a thickness (not shown) of the flexible substrate (not shown) is between about 1:2 and 1:10. Due to the formation of the trench  120 , while external stress (not shown) is applied to the flexible substrate  102  and causes tensile strain thereto, the tensile strain at the supporting portion  102   b  can be further reduced and maintains an amount of tensile strain less than 10%. The amount of tensile strain mentioned above is defined as [(a size of a portion prior to deformation−a size of a portion after deformation)/a size of a portion prior to deformation]*100%. In addition, the trench  120  may have a shape similar to the shape of an edge of the supporting portion  102   b  from a top view. Since the supporting portion  102   b  is formed with a circular configuration, such that the trench  120  may have a curved configuration. However, in other embodiments, for example the embodiments shown in  FIGS. 5-7 , the trench  120  can also be additionally formed, and the shape of the trench  120  is not limited to the shape shown in  FIG. 8  and may have a configuration similar with a shape of an edge of the supporting portion shown in  FIGS. 5-7 . 
         [0032]      FIG. 9  is a schematic perspective view showing another exemplary flexible substrate  102  applicable in the flexible electronic module  100  shown in  FIGS. 1-3 . The exemplary flexible substrate  102  in  FIG. 9  is similar with that shown in  FIG. 8 , and a difference therebetween is the trench  120  shown in  FIG. 9  is disposed at a place adjacent to the connection portion  102   c  and the trench  120  is composed of an L-shape trench  120   a  and an inverted L-shaped trench  102   b  connected to an end of trench  104 , respectively. Therefore, while external stress (not shown) is applied to the flexible substrate  102  and causes tensile strain thereto, the tensile strain at the supporting portion  102   b  can be further reduced. The trench  120  in the embodiment has an Ω configuration from a top view. 
         [0033]      FIG. 10  is a schematic perspective view showing yet another flexible substrate  102  applicable in the flexible electronic module  100  shown in  FIGS. 1-3 . The exemplary flexible substrate  102  in  FIG. 10  is similar with that in  FIG. 10  and further comprises a recess  300  formed in a portion of the body portion  102   a , such that while an external stress (not shown) is applied to the flexible substrate  102  and causes tensile strain thereto, the tensile strain at the supporting portion  102   b  can be further reduced. As shown in  FIG. 10 , the recess  300  extends beneath the supporting portion  102   b , the connection portion  102   c , and the trenches  104  and  120 , thereby suspending the supporting portion  102   b , the connection portion  102   c , and the trenches  104 . 
         [0034]      FIG. 11  is a schematic perspective view showing another flexible substrate  102  applicable in the flexible electronic module  100  shown in  FIGS. 1-3 . The exemplary flexible substrate  102  in  FIG. 11  is similar with that shown in  FIG. 8 , and a trench  140  is further formed at a place adjacent to two ends of the trench  104  adjacent to the connection portion  102   c , respectively. At this time, the trenches  140  are disposed near two ends of the trench  104  adjacent to the connection portion  102   c , respectively, and the trench  120  is disposed in the body portion  102   a  and extends in parallel with the two trenches  140  and the portion of the trench  104  connected therewith, thereby defining a line-routing portion  102   d  in the body portion  102 . As shown in  FIG. 11 , surfaces of the body portion  102   a , the supporting portion  102   b , the connection portion  102   c , and the line-routing portion  102   d  may be a coplanar, and the connection portion  102   c  is connected with a portion of the supporting portion  102   b  and a portion of the line-routing portion  102   d . Herein, a ratio between a depth (not shown) of the trench  140  to a thickness (not shown) of the substrate is between about 1:2 and 1:10, and a ratio between a depth (not shown) of the trench  120  to a thickness (not shown) of the substrate is between about 1:2 and 1:10. Therefore, the conductive lines  108  in the flexible electronic module  100  can be extended from the supporting portion  102   b  to the line-routing portion  102   d  through the connection portion  102   c  to form electrical connections between the electronic device  106  and external electronic devices or conductive lines (both not shown). Due to formation of the trenches  104 ,  140 , and  120 , the body portion  102   a , and the line-routing portion  102   d , such that while external stress (not shown) is applied to the flexible substrate  102  and causes tensile strain thereto, the tensile strain at the supporting portion  102   b  can be further reduced and maintains an amount of tensile strain less than 10%. The amount of tensile strain mentioned above is defined as [(a size of a portion prior to deformation−size of a portion after deformation)/a size of a portion before deformation]*100%. 
         [0035]      FIG. 12  is a schematic perspective view showing another exemplary flexible substrate  102  applicable in the flexible electronic module  100  shown in  FIGS. 1-3 . The exemplary flexible substrate  102  in  FIG. 12  is similar with that shown in  FIG. 8 , and the body portion  102   a  shown in  FIG. 12  is partially removed by, for example, a selective etching, to make surfaces of the supporting portion  102   b  and the connection portion  102   c  surrounded by the trench  104  above a surface of the body portion  102   a . In addition, a portion of the body portion  102   a  connected with the connection portions  102   c  between the trenches  104  and  120  is also patterned by, for example, a selective etching to form a line-routing portion  102   d , and ensure that a surface of the line-routing portion  102   d  is above a surface of the body portion  102   a  and is coplanar with surfaces of the supporting portion  102   b  and the connection portion  102   c . As shown in  FIG. 12 , the connection portion  102   c  is connected to a portion of the supporting portion  102   b  and a portion of the line-routing portion  102   d , and the line-routing portion  102   d  may face opposite sides of the connection portion  102   c  and extends over the body portion  102  in any shape. Therefore, the conductive lines  108  in the flexible electronic module  100  shown in  FIGS. 1-3  may extend from the supporting portion  102   b  to the line-routing portion  102   d  through the connection portion  102   c , thereby forming electrical connections between the electronic device  106  to external electronic devices or conductive lines (both not shown). In this embodiment, due to formation of the trenches  104  and  120 , the body portion  102   a  and the line-routing portion  102   d , such that while external stress (not shown) is applied to the flexible substrate  102  and causes tensile strain thereto, the tensile strain at the supporting portion  102   b  can be further reduced and maintains an amount of tensile strain less than 10%. The amount of tensile strain mentioned above is defined as [(a size of a portion prior to deformation−a size of a portion after deformation)/a size of a portion before deformation]*100%. A ratio of a height (not shown) of the line-routing portion  102   d  to a thickness (not shown) of the substrate is between about 1:50 and 1:1. 
         [0036]      FIG. 13  is a schematic perspective view showing another exemplary flexible substrate  102  applicable in the flexible electronic module  100  shown in  FIGS. 1-3 . The exemplary flexible substrate  102  is similar with that shown in  FIG. 4 , and a line-routing portion  102   d  is further defined over the flexible substrate  102  due to formation of the trench  104 , such that a surface of the body portion  102   a  of the flexible substrate  102  is lower than surfaces of the supporting portion  102   b , the connection portion  102   c  and the line-routing portion  102   d . The connection portion  102   c  is connected with a portion of the supporting portion  102   b  and a portion of the line-routing portion  102   d , and a portion of the trench  104  is also formed in a portion between the supporting portion  102   b  and the line-routing portion  102   d  connected by the connection portion  102   c . Therefore, the conductive lines  108  in the flexible electronic module  100  shown in  FIGS. 1-3  may extend from the supporting portion  102   b  to the line-routing portion  102   d  through the connection portion  102   c  to form electrical connections between the electronic device  106  and external electronic devices or conductive lines (both not shown). Due to formation of the trench  104 , the body portion  102   a  and the line-routing portion  102   d , while external stress (not shown) is applied to the flexible substrate  102  and causes tensile strain thereto, the tensile strain at the supporting portion  102   b  can be further reduced. The amount of tensile strain mentioned above is defined as [(a size of a portion prior to deformation−a size of a portion after deformation)/a size of a portion before deformation]*100%. 
         [0037]    In the embodiment shown in  FIG. 13 , a depth of the trench  104  is equal to a difference of heights between the supporting portion  102   b  and the body portion  102   a , but is not limited thereto. The trench  104  may be further etched by a laser cutting to make the depth of the trench  104  greater than a height difference between the supporting portion  102   b  and the body portion  102   a.    
         [0038]    In the exemplary flexible substrates  102  applicable in the flexible electronic module  100  as shown in  FIGS. 4-13 , additional components such as the electronic device  106  and the conductive lines  108  (both not shown) can be further provided and disposed thereover for forming flexible electronic modules similar with the flexible electronic module  100  shown in  FIGS. 1-3 . Similar to that shown in  FIGS. 1-3 , the electronic device  106  can be disposed over the supporting-portion  102   b , and the conductive lines  108  can be disposed over the supporting-portion  102   b , the connection portion  102   c  and the body-portion  102   a  or the line-routing portion  102   d.    
       Tensile Strain Test; 
       [0039]    A software Autodesk® Inventor® 3D CAD is used to simulate a flexible substrate made of polydimethylsiloxane (PDMS) materials applied with a tensile stress of 1.2 N on both x and y directions thereto, and the flexible substrate has a size of 3 mm×3 mm×1 mm (length×width×height), and an amount of tensile strain at various points A, B, C, and D is measured. The amount of tensile strain mentioned above is defined as [(a size of a portion before deformation−a size of a portion after deformation)/a size of a portion before deformation]*100%. Characteristics of the flexible substrate in the disclosure are described in table 1 as follows. 
         [0000]    
       
         
               
               
             
               
               
               
               
             
           
               
                 TABLE 1 
               
               
                   
               
             
             
               
                 Material of flexible 
                 polydimethylsiloxane (PDMS) 
               
               
                 substrate 
               
             
          
           
               
                 General 
                 Mass density 
                 1.03 
                 g/cm 3   
               
               
                 characteristics 
                 Subdue strength 
                 0.13 
                 MPa 
               
               
                   
                 ultimate anti-pull strength 
                 7.1 
                 MPa 
               
               
                 Stress 
                 Young&#39;s modulus 
                 0.00075 
                 GPa 
               
               
                 characteristics 
                 Poisson&#39;s ratio 
                 0.49 
                 μl 
               
               
                   
                 Shear modulus 
                 0.000251678 
                 GPa 
               
               
                   
               
             
          
         
       
     
       Example 1 
       [0040]    The flexible substrate  102  shown in  FIG. 4  is provided to perform the tensile strain test described above. The trench  104  in the flexible substrate  102  has a width of 0.1 mm and a depth of 0.15 mm, and the supporting portion  102   b  has a circular shape of a radius of 0.5 mm from a top view. Simulation results of the amount of tensile strain at the various locations A, B, C and D over the body portion  102   a , the supporting portion  102   b , and the connection portion  102   c  shown in  FIG. 4  are shown in table 2 as follows. 
         [0000]    
       
         
               
               
               
             
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                   
                 TABLE 2 
               
             
             
               
                   
                   
               
               
                   
                 Location of Measurement 
                   
               
             
          
           
               
                   
                 A 
                 B 
                 C 
                 D 
               
               
                   
                   
               
             
          
           
               
                   
                 Amount of strain in 
                 1% 
                 22% 
                 22% 
                 27% 
               
               
                   
                 X direction 
               
               
                   
                 Amount of strain in 
                 1% 
                 78% 
                 20% 
                 21% 
               
               
                   
                 Y direction 
               
               
                   
                   
               
             
          
         
       
     
       Example 2 
       [0041]    The flexible substrate  102  shown in  FIG. 8  is provided to perform the tensile strain test described above. The trenches  104  and  120  in the flexible substrate  102  have a width of 0.1 mm and a depth of 0.15 mm, respectively. The connection portion  102   c  and the trench  120  have a pitch P of 0.2 mm therebetween, and the supporting portion  102   b  has a circular shape of a radius of 0.5 mm from a top view. Simulation results of the amount of tensile strain at the various locations A, B, C and D over the body portion  102   a , the supporting portion  102   b , and the connection portion  102   c  shown in  FIG. 8  are shown in table 3 as follows. 
         [0000]    
       
         
               
               
               
             
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                   
                 TABLE 3 
               
             
             
               
                   
                   
               
               
                   
                 Location of Measurement 
                   
               
             
          
           
               
                   
                 A 
                 B 
                 C 
                 D 
               
               
                   
                   
               
             
          
           
               
                   
                 Amount of strain in 
                 2% 
                  6% 
                 54% 
                 24% 
               
               
                   
                 X direction 
               
               
                   
                 Amount of strain in 
                 2% 
                 18% 
                 21% 
                 29% 
               
               
                   
                 Y direction 
               
               
                   
                   
               
             
          
         
       
     
       Example 3 
       [0042]    The flexible substrate  102  shown in  FIG. 11  is provided to perform the tensile strain test described above. The trenches  104  and  120  in the flexible substrate  102  have a width of 0.1 mm and a depth of 0.15 mm, respectively, the line-routing portion  102   d  has a width of 0.2 mm, and the supporting portion  102   b  has a circular shape of a radius of 0.5 mm from a top view. Simulation results of the amount of tensile strain at the various locations A, B, C and D over the body portion  102   a , the supporting portion  102   b , the connection portion  102   c , and the line-routing portion  102   d  shown in  FIG. 8  are shown in table 4 as follows. 
         [0000]    
       
         
               
               
               
             
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                   
                 TABLE 4 
               
             
             
               
                   
                   
               
               
                   
                 Location of Measurement 
                   
               
             
          
           
               
                   
                 A 
                 B 
                 C 
                 D 
               
               
                   
                   
               
             
          
           
               
                   
                 Amount of strain in 
                 1% 
                 15% 
                 22% 
                 30% 
               
               
                   
                 X direction 
               
               
                   
                 Amount of strain in 
                 4% 
                 34% 
                  7% 
                 30% 
               
               
                   
                 Y direction 
               
               
                   
                   
               
             
          
         
       
     
       Example 5 
       [0043]    The flexible substrate  102  shown in  FIG. 12  is provided to perform the tensile strain test described above. The trenches  104  and  120  in the flexible substrate  102  have a width of 0.1 mm and a depth of 0.15 mm, respectively, the line-routing portion  102   d  has a width of 0.2 mm and a height of 0.02 mm (related to a surface of the body portion  102   a ), the connection portion  102   c  and the trench  102  has a pitch P of 0.2 mm therebetween, and the supporting portion  102   b  has a circular shape of a radius of 0.5 mm from a top view. Simulation results of the amount of tensile strain at the various locations A, B, C and D over the body portion  102   a , the supporting portion  102   b , and the connection portion  102   c  shown in  FIG. 12  are shown in table 5 as follows. 
         [0000]    
       
         
               
               
               
             
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                   
                 TABLE 5 
               
             
             
               
                   
                   
               
               
                   
                 Location of Measurement 
                   
               
             
          
           
               
                   
                 A 
                 B 
                 C 
                 D 
               
               
                   
                   
               
             
          
           
               
                   
                 Amount of strain in 
                 2% 
                 13% 
                 38% 
                 26% 
               
               
                   
                 X direction 
               
               
                   
                 Amount of strain in 
                 4% 
                 22% 
                 19% 
                 29% 
               
               
                   
                 Y direction 
               
               
                   
                   
               
             
          
         
       
     
       Example 5 
       [0044]    The flexible substrate  102  shown in  FIG. 13  is provided to perform the tensile strain test described above. The trench  104  between the supporting portion  102   b  and the line-routing portion  102   d  has a width of 0.1 mm and a depth of 0.15 mm, and the line-routing portion  102   d  has a width of 0.2 mm, and the supporting portion  102   b  has a circular shape of a radius of 0.5 mm from a top view. Simulation results of the amount of tensile strain at the various locations A, B, C and D over the body portion  102   a , the supporting portion  102   b , the connection portion  102   c , and the line-routing portion  102   d  shown in  FIG. 13  are shown in table 6 as follows. 
         [0000]    
       
         
               
               
               
             
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                   
                 TABLE 6 
               
             
             
               
                   
                   
               
               
                   
                 Location of Measurement 
                   
               
             
          
           
               
                   
                 A 
                 B 
                 C 
                 D 
               
               
                   
                   
               
             
          
           
               
                   
                 Amount of strain in 
                 3% 
                  6% 
                 14% 
                 31% 
               
               
                   
                 X direction 
               
               
                   
                 Amount of strain in 
                 3% 
                 25% 
                 39% 
                 31% 
               
               
                   
                 Y direction 
               
               
                   
                   
               
             
          
         
       
     
         [0045]    It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the disclosure without departing from the scope or spirit of the disclosure. In view of the foregoing, it is intended that the disclosure cover modifications and variations of this disclosure provided they fall within the scope of the following claims and their equivalents.