Abstract:
A liquid crystal panel incorporating a chips on glass (COG) system has a significantly increased field area and greatly reduced glass substrate size because driving integrated circuit chips for applying signals to electrode pads connected to pixels and flexible printed circuit films for applying electrical signals to the driving integrated circuit chips are overlappedly mounted on a lower glass substrate.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a liquid crystal display apparatus, and more particularly, to a liquid crystal panel incorporating a “chips-on-glass” (COG) system wherein integrated circuit (IC) chips are directly mounted on a glass substrate. Also, the present invention is directed to a method of manufacturing a COG type liquid crystal panel. 
     2. Description of the Related Art 
     Since a liquid crystal display apparatus display has advantages including a light weight, a small thickness, a low power consumption and so on, its applications have been steadily enlarged. The liquid crystal display apparatus includes a picture display having picture elements or pixels of liquid crystal arranged in a matrix pattern, and driving IC chips, hereinafter referred to as D-IC chips, for driving the liquid crystal display. Recently, a liquid crystal display apparatus has been manufactured using the COG system in which D-IC chips are directly mounted on the edge of a glass substrate. Also, the COG type liquid crystal panel makes use of a flexible printed circuit (FPC) film for applying signals to the D-IC chips. 
     In such a COG type liquid crystal panel, since the D-IC chips and the FPC film are mounted at different positions on the glass substrate, the effective field area is small and the size of liquid crystal panel is large. Further, the FPC film includes a wiring for commonly applying electric signals to all the D-IC chips. This results in an increase in the wiring amount of the FPC film, as well as an increase in the manufacturing cost of FPC film and an increase in the manufacturing cost of liquid crystal panel. 
     For example, as shown in FIG.  1 A and FIG. 1B, the COG type liquid crystal panel includes D-IC chips  6  mounted on the edge of a lower glass substrate  4  in such a manner to be positioned between an upper glass substrate  2  and a FPC film  8 . A picture display having liquid crystal cells and thin film transistors (TFTs) arranged in a matrix pattern is formed between the lower glass substrate  4  and the upper glass substrate  2 . The edge of the lower glass substrate  4  mounted with the D-IC chips  6  and the FPC film  8  is usually referred to as a “pad area” because electrode pads for supplying signals to drive the TFTs are located at the edge of the lower glass substrate  4 . In this pad area, output wiring electrodes (not shown) are provided for connecting the D-IC chips  6  with the picture display and input wiring electrodes (not shown) are provided for connecting the D-IC chips  6  and the FPC film. The D-IC chips  6  are provided to drive the TFTs and are adhered to the pad area via an anisotropic conductive film (ACF)  10  and bumps  10 A in such a manner to be electrically connected to the input and output wiring electrodes. The FPC film  8  is mounted with a wiring for transferring electrical signals, e.g., video data signals, timing control signals and voltage signals, from a control circuit (not shown) to the D-IC chips  6 . Such a FPC film  8  also is adhered to the pad area via the ACF  10  and the bumps l 0 A in such a manner to be electrically connected to the input wiring electrodes. 
     As described above, in the conventional COG type liquid crystal panel, the D-IC chips and the FPC film are mounted in parallel at the pad area, causing the pad area to be enlarged. As a result of this mounting arrangement, the field area becomes small and the size of glass substrate becomes large. Further, in the conventional COG type liquid crystal panel, the FPC film is adhered to the pad area on the lower glass substrate such that it is located at positions corresponding to locations of all of the D-IC chips. This results in an increase in a wiring amount located at the FPC film and an increase in the manufacturing cost of the FPC film and a increase in the manufacturing cost of the liquid crystal panel. 
     SUMMARY OF THE INVENTION 
     In order to overcome the problems described above, preferred embodiments of the present invention provide a COG type liquid crystal panel that is adapted to enlarge a field area and to reduce the size of a glass substrate, and a method for such a COG type liquid crystal panel. 
     In addition, the preferred embodiments of the present invention provide a COG type liquid crystal panel that is adapted to simplify a FPC film, and a method for making such a COG type liquid crystal panel with a simplified FPC. 
     According to one aspect of preferred embodiments of the present invention, a liquid crystal panel incorporating a chips-on-glass (COG) system and having a plurality of pixels arranged between an upper glass substrate and a lower glass substrate, and electrode pads connected to the pixels on the lower glass substrate, including driving integrated circuit chips mounted on the lower glass substrate to apply signals to the electrode pads, and a flexible printed circuit film mounted on the lower glass substrate to overlap the driving integrated circuit chips for applying electrical signals to the driving integrated circuit chips. 
     According to another preferred embodiment of the present invention, a liquid crystal panel incorporating a COG system and having a plurality of pixels arranged between an upper glass substrate and a lower glass substrate includes first electrode pads connected to the pixels on the lower glass substrate and second electrode pads located on the lower glass substrate and substantially parallel to the first electrode pads, including a signal wiring disposed on the lower glass substrate to intersect the second electrode pads and to be coupled to a portion of the second electrode pads, a plurality of driving integrated circuit chips mounted on the lower glass substrate so as to be electrically coupled to the first and second electrode pads, and a flexible printed circuit film mounted on the lower glass substrate so as to be electrically coupled to the signal wiring and the remaining second electrode pads, for applying electrical signals to the driving integrated circuit chips. 
     According to still another aspect of preferred embodiments the present invention, there is provided with a liquid crystal panel of COG system having a plurality of pixels arranged between an upper glass substrate and a lower glass substrate, first electrode pads connected to the pixels on the lower glass substrate, and second electrode pads on the lower glass substrate and substantially parallel to the first electrode pads, including a signal wiring located on the lower glass substrate to intersect the second electrode pads and to be coupled to a part of the second electrode pads, a plurality of driving integrated circuit chips mounted on the lower glass substrate to be electrically coupled to the first and second electrode pads, a first flexible printed circuit film mounted on the lower glass substrate to be electrically coupled to the signal wiring for applying first electrical signals to the driving integrated circuit chips, and a second flexible printed circuit film mounted at the upper portion of the driving integrated circuit chips to apply second electrical signals to the driving integrated circuit chips. 
     According to still another preferred embodiment of the present invention, a method of manufacturing a liquid crystal panel incorporating a COG system and including the steps of preparing a glass substrate having a plurality of pixels and electrode pads formed thereon, the electrode pads being connected to the pixels, adhering a first anisotropic conductive film to the upper portions of the electrode pads, arranging first conductive bumps on the first anisotropic conductive film to correspond to positions of the electrode pads, disposing a flexible printed circuit film at the upper portions of the first conductive bumps, pressing the flexible printed circuit film, adhering a second anisotropic conductive film to the upper portion of the flexible printed circuit film, arranging second conductive bumps along both edges of the second anisotropic conductive film, arranging driving integrated circuit chips at the upper portions of the second conductive bumps, and pressing the driving integrated circuit chips. 
     According to still another preferred embodiment of the present invention, a method of manufacturing a liquid crystal panel incorporating a COG system includes the steps of preparing a glass substrate having a plurality of pixels and electrode pads formed thereon, the electrode pads being connected to the pixels, adhering a first anisotropic conductive film to the upper portions of the electrode pads, arranging first conductive bumps on the first anisotropic conductive film to correspond to positions of the electrode pads, arranging driving integrated circuit chips at the upper portions of the first conductive bumps, pressing the driving integrated circuit chips, adhering a second anisotropic conductive film to the upper portions of the driving integrated circuit chips, arranging second conductive bumps along both edges of the second anisotropic conductive film, disposing a flexible printed circuit film at the upper portions of the second conductive bumps and pressing the flexible printed circuit film. 
     According to still another aspect of preferred embodiments of the present invention, a method of manufacturing a liquid crystal panel incorporating a COG system, includes the steps of preparing a glass substrate having a plurality of pixels having first electrode pads and second electrode pads formed thereon, the first electrode pads being connected to the pixels and the second electrode pads being arranged to be substantially parallel to the first electrode pads, forming a signal wiring on the glass substrate to intersect the second electrode pads and to be connected to a part of the second electrode pads, adhering an anisotropic conductive film to the upper portions of the first and second electrode pads and the signal wiring, arranging conductive bumps on the anisotropic conductive film to correspond to locations of the first and second electrode pads and the signal wiring, arranging driving integrated circuit chips and a flexible printed circuit film at the upper portions of the conductive bumps, and pressing the driving integrated circuit chips and the flexible printed circuit film. 
     According to still another aspect of preferred embodiments of the present invention, a method of manufacturing a liquid crystal panel incorporating a COG system, includes the steps of preparing a glass substrate having a plurality of pixels, first electrode pads and second electrode pads formed thereon, the first electrode pads being connected to the pixels and the second electrode pads being arranged in parallel to the first electrode pads, forming a signal wiring on the glass substrate to intersect the second electrode pads and to be connected to a part of the second electrode pads, adhering a first anisotropic conductive film to the upper portions of the first and second electrode pads and the signal wiring, arranging first conductive bumps at the upper portion of the first anisotropic conductive film to correspond with the first and second electrode pads and the signal wiring, arranging driving integrated circuit chips and a first flexible printed circuit film at the upper portions of the first conductive bumps, pressing the driving integrated circuit chips and the first flexible printed circuit film, adhering a second anisotropic conductive film to the upper portions of the driving integrated chips, arranging second conductive bumps at the upper portion of the second anisotropic conductive film, positioning a second flexible printed circuit film at the upper portions of the second conductive bumps, and pressing the second flexible printed circuit film. 
     Other features and advantages of the present invention will become apparent from the following description of preferred embodiments of the invention which refers to the accompanying drawings, wherein like reference numerals indicate like elements to avoid duplicative description. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1A is a schematic plan view of a conventional COG type liquid crystal panel; 
     FIG. 1B is a schematic section view of the conventional COG type liquid crystal panel; 
     FIG. 2A is a schematic plan view of a COG type liquid crystal panel according to a first preferred embodiment of the present invention; 
     FIG. 2B is a schematic section view of a COG type liquid crystal panel according to a first preferred embodiment of the present invention; 
     FIG. 3A is a schematic plan view of a COG type liquid crystal panel according to a second preferred embodiment of the present invention; 
     FIG. 3B is a schematic section view of a COG type liquid crystal panel according to a second preferred embodiment of the present invention; 
     FIG. 4A is a schematic plan view of a COG type liquid crystal panel according to a third preferred embodiment of the present invention; 
     FIG. 4B is a schematic section view of a COG type liquid crystal panel according to a third preferred embodiment of the present invention; 
     FIG. 5A is a schematic plan view of a COG type liquid crystal panel according to a fourth preferred embodiment of the present invention; and 
     FIG. 5B is a schematic section view of a COG type liquid crystal panel according to a fourth preferred embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     Referring to FIG.  2 A and FIG. 2B, there is shown a COG type liquid crystal panel according to a first preferred embodiment of the present invention. The COG type liquid crystal panel includes an upper glass substrate  12  provided arranged to face an upper portion of a lower glass substrate  14 , a FPC film  18  mounted at a pad area of the lower glass substrate  12  which is located at an edge portion of the lower glass substrate  12 , and D-IC chips  16  mounted at the upper portion of the FPC film  18 . Picture displays having liquid crystal cells and TFTs arranged in a matrix pattern are located between the upper glass substrate  12  and the lower glass substrate  14 . The FPC film  18  is adhered to the pad area on the lower glass substrate  14  via an anisotropic conductive film ACF  20  and is electrically coupled with electrode pads  24  connected to the liquid crystal display via connecting bumps  22 A. Dummy bumps  22 B are also provided for support and stability of the FPC  18  and D-IC chips  16 . The D-IC chips  16  are adhered to the upper portion of the FPC film  18  via the ACF  20 . Also, the D-IC chips  16  are electrically coupled with the FPC film  18  via input bumps  22 C and output bumps  22 D. The input bumps  22 C deliver signals from the FPC film  18  to the D-IC chips  16  and the output bumps  22 D deliver signals from the D-IC chips  16  to both the FPC film  18  and the interfacing bumps  22 A. In other words, the FPC film  18  positioned between the lower glass substrate  14  and the D-IC chips  16  transfers electrical signals from a control circuit (not shown) to the D-IC chips  16 . At the same time, the FPC film  18  transfers TFT driving signals from the D-IC chips  16  to the electrode pads  24  connected to the picture display. As mentioned above, the D-IC chips  16  and the FPC film  18  are overlappedly mounted at the pad area on the lower glass substrate  4 , thereby reducing the size of pad area. As a result of the above-described unique arrangement, the field area of the COG type liquid crystal panel is significantly increased and the size of the COG type liquid crystal panel is significantly decreased. 
     A method of manufacturing the above-mentioned COG type liquid crystal panel which is overlappedly mounted with the FPC film  18  and the D-IC chips  16  will be described in detail below. First, the ACF  20  is attached to the pad area of the lower glass substrate  14  to which the upper glass substrate  12  is adhered. The interfacing bumps  22 A and dummy bumps  22 B are preferably arranged substantially in parallel at both edges of the ACF  20 , and the FPC film  18  is mounted on the upper portions of the interfacing bumps  22 A and the dummy bumps  22 B. The FPC film  18  disposed on the upper portions of the connecting bumps  22 A and the dummy bumps  22 B is pressed toward the lower glass substrate  14  via application of downward pressure, and is electrically coupled with the electrode pads  24 . Next, after the ACF  20  is attached to the upper portion of the FPC film  18 , the input bumps  22 C and the output bumps  22 D are preferably arranged substantially in parallel at both edges of the ACF  20 . The D-IC chips  16  are arranged at the upper portions of the input and output bumps  22 C and  22 D. The D-IC chips  16  disposed on the upper portions of the input and output bumps  22 C and  22 D are pressed toward the FPC film  18  via application of downward pressure and are electrically coupled with the FPC film  18 . 
     Referring to FIG.  3 A and FIG. 3B, there is shown a COG type liquid crystal panel according to a second preferred embodiment of the present invention. The COG type liquid crystal panel includes an upper glass substrate  12  adhered to the upper portion of the lower glass substrate  14 , D-IC chips  16  mounted at a pad area on the lower glass substrate  12 , and a FPC film  18  mounted at the upper portion of the D-IC chips  16 . Picture displays having liquid crystal cells and TFTs arranged in a matrix pattern are disposed between the upper glass substrate  12  and the lower glass substrate  14 . The D-IC chips  16  are adhered to the pad area on the lower glass substrate  14  via an ACF  20  and are electrically coupled with electrode pads  24  connected to the liquid crystal display via output bumps  22 D. Also, the D-IC chips  16  receive electrical signals, transmitted via input bumps  22 C positioned at the upper portion thereof, from the FPC film  18 . Dummy bumps  22 B positioned between the edge of the lower glass substrate  14  and the output bumps  22 D support the D-IC chips  16  in a reliable and stable manner. The FPC film  18  is adhered to the upper portions of the D-IC chips  16  via the ACF  20  and is electrically coupled with the D-IC chips via input bumps  22   c.  The D-IC chips  16  output TFT control signals for driving the TFTs, via output bumps  22 D, to the electrode pads  24  in response to electrical signals inputted, via the input bumps  22 C, from the FPC film  18 . The FPC film  18  transfers electrical signals from a control circuit (not shown) to the D-IC chips  16 . As mentioned above, the D-IC chips  16  and the FPC film  18  are overlappedly mounted at the pad area on the lower glass substrate  14 , thereby reducing the size of pad area. As a result of this unique arrangement, the field area of the COG type liquid crystal panel is significantly increased and the size of the COG type liquid crystal panel is greatly reduced. 
     A method of manufacturing the above-mentioned COG type liquid crystal panel which is overlappedly mounted with the FPC film  18  and the D-IC chips  16  will be described in detail below. First, the AFC  20  is attached to the pad area of the lower glass substrate  14  to which the upper glass substrate  12  is adhered. The output bumps  22 D and the dummy bumps  22 B are preferably arranged substantially in parallel at both edges of the ACF  20 , and the D-IC chips  16  are mounted on the upper portions of the output bumps  22 D and the dummy bumps  22 B. The D-IC chips  16  disposed on the upper portions of the output bumps  22 D and the dummy bumps  22 B are pressed toward the lower glass substrate  14  via application of downward pressure and are electrically coupled with the electrode pads  24 . Next, after the ACF  20  is attached to the upper portion of the FPC film  18  again, the input bumps  22 C are arranged preferably along a line at the outer edges of the ACF  20 . The FPC film  18  is mounted on the upper portions of the input bumps  22 C. The FPC film  18  disposed on the upper portions of the input bumps  22 C is pressed toward the D-IC chips  16  via application of downward pressure and is electrically coupled with the D-IC chips  16 . 
     Referring to FIG.  4 A and FIG. 4B, there is shown a COG type liquid crystal panel according to a third preferred embodiment of the present invention. The COG type liquid crystal panel includes an upper glass substrate  12  adhered to the upper portion of a lower glass substrate  14 , D-IC chips  16  mounted at a pad area on the lower glass substrate  12 , and a FPC film  30  mounted at the pad area of the lower glass substrate  14  so as to surround the peripheries of the D-ICs  16 . Picture displays having liquid crystal cells and TFTs arranged in a matrix pattern are located between the upper glass substrate  12  and the lower glass substrate  14 . Input electrode pads  32 , signal wiring  34  and output electrode pads  36  are provided at the pad area on the lower glass substrate  14 . The input electrode pads  32  extend from the edge of the lower glass substrate  14  to the end portions of the output electrode pads  36 . The output electrode pads  36  are coupled with the liquid crystal display. The signal wiring  34  is located at upper portions of the input electrode pads  32  positioned at sides adjacent to the output electrode pads  36 . In other words, the signal wiring  34  intersects the input electrode pads  32  at a position where the D-IC chips  16  are to be mounted. An insulating layer  38  is located between the input electrode pads  32  and the signal wiring  34 . The input electrode pads  32  are electrically coupled to the signal wiring  34  via contacts passing through the insulating layer  38 . The D-IC chips  16  are adhered to the pad area on the lower glass substrate  14  via an ACF  20  such that the D-IC chips  16  are positioned at the upper portions of the signal wiring  34 . Also, the D-IC chips  16  are electrically coupled with the input electrode pads  32  and the output electrode pads  36  via input bumps  22 C and output bumps  22 D. The FPC film  30  has a base film  30 A adhered to one end of the pad area on the lower glass substrate  14 , and a branch film  30 B and a dummy film  30 C, each of which preferably extends substantially parallel to each side of the D-IC chips  16  from one end of the base film  30 A. The center of one end of the base film  30 A is adhered to the lower glass substrate  14  via the ACF  20 , and is electrically coupled to the signal wiring  34  via conductive bumps (not shown). The branch film  30 B and the dummy film  30 C also are adhered to the lower glass substrate  14  via the ACF  20 . The branch film  30 B is electrically coupled to the input electrode pads  32  by connecting bumps  22 A and the dummy film  30 C is supported by the dummy bumps  22 B so as to be electrically disconnected from the output electrode pads  36 . In other words, the dummy film  30 C is used as an auxiliary supporting member allowing the FPC film  30  to be adhered onto the lower glass substrate  14  in a stable and reliable manner. The FPC film  30  mounted at the pad area on the lower glass substrate  14  in this manner transfers a portion of electrical signals from a control circuit (not shown) via the signal wiring  34 , to the input electrode pads  32 . At the same time, the FPC film  30  transfers the remaining electrical signals to the input electrode pads  32  directly. In this case, the electrical signals passing through the signal wiring  34  are not sensitive to a resistance like driving voltage signals. In contrast, the electrical signals delivered from the branch film  30 B to the input electrode pads  32  directly are sensitive to a resistance like video data and timing control signals. As described above, the portion of electrical signals directly delivered from the FPC film  30  is relayed via the signal wiring  34  located on the lower glass substrate  16 , thereby simplifying a wiring structure of the FPC film  30 . Accordingly, it is possible to reduce the manufacturing cost of FPC film and the manufacturing cost of COG type liquid crystal panel. Further, the signal wiring  34  is arranged to overlap with the D-IC chips  16 , thereby reducing the pad margin. As a result, the COG liquid crystal panel constructed as described above has a significantly reduced size and increased field area. 
     A method of manufacturing such a COG type liquid crystal panel will be described in detail below. First, there is prepared the lower glass substrate  14  having the upper glass substrate  12  adhered, and having the input electrode pads  32 , the signal wiring  34  and the output electrode pads  36  formed at the pad area thereof. The input electrode pads  32  and the output electrode pads  36  is formed by coating a conductive material layer of the same conductive material as the source and drain of the TFT thereon and then patterning the conductive material layer. The signal wiring is formed by defining the insulating layer  38  at the upper portions of the input electrode pads  32  and the output electrode pads  34 , forming contact holes for exposing the input electrode pads  32  at the insulating layer  38 , depositing a conductive material layer of the same conductive material as the source and drain of the TFT to bury the contact holes, and patterning the conductive material layer and the insulating layer, sequentially. Next, after the ACF  20  is attached to the pad area on the lower glass substrate  16 , conductive bumps(not shown) together with the connecting bumps  22 A, the input bumps  22 C, the output bumps  22 D and the dummy bumps  22 B, are preferably arranged substantially in parallel at the upper portion of the ACF  20 . The D-IC chips  16  are disposed on the upper portions of the input bumps  22 C and the output bumps  22 D. The branch film  30 B is mounted onto the upper portion of the connecting bumps  22 A. The dummy film  30 C is mounted on the dummy bumps  22 B. The base film  30 A is mounted on the upper portions of the conductive bumps (not shown). The D-IC chips  16 , the base film  30 A, the branch film  30 B, the branch film  30 B and the dummy film  30 C are adhered to the lower glass substrate  16  via application of a downward force. At this time, the branch film  30 B is connected to the input electrode pads  32  via the interfacing bumps  22 A, and the base film  30 A is electrically coupled to the signal wiring  34  via the conductive bumps. Also, the D-IC chips  16  are electrically coupled to both the input electrode pads  32  and the output electrode pads via the input bumps  22 C and the output bumps  22 D. 
     Referring to FIG.  5 A and FIG. 5B, there is shown a COG type liquid crystal panel according to a third preferred embodiment of the present invention. The COG type liquid crystal panel includes an upper glass substrate  12  adhered to the upper portion of a lower glass substrate  14 , D-IC chips  16  mounted at a pad area on the lower glass substrate  12 , and a FPC film  42  for applying electrical signals to the D-IC chips  16 . Picture displays having liquid crystal cells and TFTs arranged in a matrix pattern are located between the upper glass substrate  12  and the lower glass substrate  14 . Input electrode pads  32 , signal wiring  34  and output electrode pads  36  are defined at the pad area on the lower glass substrate  14 . The input electrode pads  32  extend from the edge of the lower glass substrate  14  to the vicinity of the end of the output electrode pads  36 . The output electrode pads  36  are coupled to the liquid crystal display. The signal wiring  34  is disposed at the upper portions of the input electrode pads  32  at a side adjacent to the output electrode pads  36 . In other words, the signal wiring  34  intersects the input electrode pads  32  at a position to be mounted with the D-IC chips  16 . An insulating layer  38  is located between the input electrode pads  32  and the signal wiring  34 . The input electrode pads  32  are electrically coupled to the signal wiring  34  via contacts  40  passing through the insulating layer  38 . The D-IC chips  16  are adhered to the pad area on the lower glass substrate  14  via an ACF  20  such that the D-IC chips  16  are positioned at the upper portions of the signal wiring  34 . Also, the D-IC chips  16  are electrically coupled with the input electrode pads  32  and the output electrode pads  36  via the input bumps  22 C and output bumps  22 D. The FPC film  42  has a base film  42 A adhered to one end of the pad area on the lower glass substrate  14 , and a tab film  42 B extending from one side corner of the base film  42 A to be mounted at the upper portions of the D-IC chips  16 . One end of the base film  42 A is adhered to the lower glass substrate  14  via the ACF  20 . At the same time, one end of the base film  42 A is electrically coupled to the signal wiring via conductive bumps (not shown). On the other hand, the tab film  42 B is adhered to the upper portions of the D-ICs  16  via the ACF  20  and, at the same time, is electrically coupled to the D-IC chips  16  via interfacing bumps  22 A. The FPC film  42  mounted at the pad area on the lower glass substrate  14  in this manner transfers a portion of electrical signals from a control circuit(not shown), via the signal wiring  34 , to the input electrode pads  32 . At the same time, the FPC film  30  transfers the remaining portions of the electrical signals to the input electrode pads  32  directly. In this case, the electrical signals passing through the signal wiring  34  are not sensitive to a resistance like driving voltage signals. In contrast, the electrical signals delivered from the tab film  42 B to the input electrode pads  32  directly are sensitive to a resistance like video data and timing control signals. As described above, the portion of electrical signals directly delivered from the FPC film  42  is relayed via the signal wiring  34  disposed on the lower glass substrate  14 , thereby simplifying a wiring structure of the FPC film  42 . Accordingly, it is possible to reduce the manufacturing cost of FPC film and the manufacturing cost of COG type liquid crystal panel. Further, both the signal wiring  34  and the FPC film  42  are arranged to overlap with the D-IC chips  16 , thereby reducing the size or area of the pad margin. As a result, the COG liquid crystal panel has a significantly reduced size while also providing a greatly increased field area. 
     A method of manufacturing such a COG type liquid crystal panel will be described in detail below. First, a lower glass substrate  14  is adhered to an upper glass substrate  12  having the input electrode pads  32 , the signal wiring  34  and the output electrode pads  36  disposed at the pad area thereof. The input electrode pads  32  and the output electrode pads  36  are preferably formed by coating a conductive material layer which is made of the same material as used for the conductive material of the source and drain of the TFT disposed thereon, and then patterning the conductive material layer. The signal wiring  34  is formed by defining the insulating layer  38  at the upper portions of the input electrode pads  32  and the output electrode pads  34 , forming contact holes for exposing the input electrode pads  32  at the insulating layer  38 , depositing a conductive material layer of the same conductive material as the source and drain of the TFT to bury the contact holes, and patterning the conductive material layer and the insulating layer, sequentially. Next, after the ACF  20  is attached to the pad area on the lower glass substrate  16 , conductive bumps (not shown) together with the input bumps  22 C and the output bumps  22 D are preferably arranged substantially in parallel at the upper portion of the ACF  20 . The D-IC chips  16  are disposed on the upper portions of the input bumps  22 C and the output bumps  22 D. The base film  42 A is mounted on the upper portions of the conductive bumps (not shown). The D-IC chips  16  and the base film  42 A are adhered to the lower glass substrate  16  via application of downward pressure. At this time, the base film  42 A is electrically coupled to the signal wiring  34  via the conductive bumps, while the D-IC chips  16  are electrically coupled to the input electrode pads  32  and the output electrode pads  36  via the input bumps  22 C and the output bumps  22 D. Subsequently, after the ACF  20  is attached to the upper portion of the D-IC chips  16  again, the interfacing bumps  22 A are preferably arranged along a line at the outer edge of the ACF  20 . The tab film  42 B defining a part of the FPC film  42  is mounted on the upper portions of the interfacing bumps  22 A. The tab film  42 A disposed on the upper portions of the interfacing bumps  22 A is pressed toward the D-IC chips  16  via application of downward pressure and, at the same time, is electrically coupled, via the interfacing bumps  22 A, to the D-IC chips  16 . 
     As described above, in the COG type liquid crystal panel according to preferred embodiments of the present invention, the D-IC chips and the FPC film are overlappedly mounted at the pad area, thereby reducing the size of the pad area. Accordingly, the COG type liquid crystal panel according to preferred embodiments of the present invention has a significantly enlarged field area and a significantly reduced size of the glass substrate. Further, in the COG type liquid crystal panel according to preferred embodiments of the present invention, a portion of electrical signals to be transferred from the FPC film to the D-IC chips is relayed via the signal wiring located on the glass substrate, thereby reducing a wiring amount of the FPC film. As a result, the COG type liquid crystal panel according to preferred embodiments of the present invention greatly simplifies a wiring structure of the FPC film and greatly reduces a cost of manufacturing of the FPC film and the liquid crystal panel. 
     Although the present invention has been explained with reference to preferred embodiments shown in the drawings described above, it should be understood to the ordinary skilled person in the art that the invention is not limited to the preferred embodiments described herein, but rather that various changes or modifications thereof are possible without departing from the spirit of the invention. Accordingly, the scope of the invention shall be determined only by the appended claims and their equivalents.