Abstract:
Gate-driving circuitry of a thin film transistor array panel is formed on the same plane as a display area of the transistor array panel. The gate-driving circuitry includes driving circuitry and signal lines having apertures. Thus, a sufficient amount of light, even though illuminated from the thin film transistor array panel side, can reach a photosetting sealant overlapping at least in part the gate-driving circuitry. The thin film transistor array panel and the counter panel are put together air-tight and moisture-tight. Consequently, the gate-driving circuitry can avoid corrosion by moisture introduced from outside. Gate-driving circuitry malfunctions can also be reduced.

Description:
RELATED APPLICATIONS 
       [0001]    This application is a continuation application of U.S. patent application Ser. No. 12/707,639, which was filed on Feb. 17, 2010 and is a continuation of U.S. Pat. No. 7,692,617, which claims the benefit and priority of Korean Patent Application Serial Nos. 10-2004-0058708 filed on Jul. 27, 2004 and 10-2004-0077500 filed on Sep. 24, 2004; the prior applications and patent are incorporated herein by reference. 
     
    
     TECHNICAL FIELD 
       [0002]    The present invention relates to display device technology and, more particularly, to the design and the application of thin film transistor array panels and display devices including such thin film transistor array panels. 
       BACKGROUND 
       [0003]    In general, a display device includes a display panel, gate-driving circuitry and data-driving circuitry. The display panel includes a thin film transistor array panel having gate lines, data lines, pixel electrodes and thin film transistors, an opposite panel having one or more common electrodes, and a liquid crystal layer provided between the two panels. The two panels are aligned and sealed by a sealant. The gate-driving circuitry and the data-driving circuitry are usually provided on a printed circuit board, or as integrated circuits connected to the display panel. 
         [0004]    Recently, the gate-driving circuitry has been formed directly on the thin film transistor array panel in order to minimize device size and to increase efficiency. In such a structure, however, a parasitic capacitance is created between the gate-driving circuitry and the common electrode or electrodes on the opposite panel, which may cause the gate-driving circuitry to malfunction. Because the dielectric constant of the sealant is less than that of the liquid crystal molecules, it has been proposed to provide the sealant between the gate-driving circuitry and the opposite panel to reduce the parasitic capacitance. 
         [0005]    As display devices become larger, the one-drop-filling (ODF) method is widely used with a photosetting sealant to provide the liquid crystal material between the two panels. The photosetting sealant, which holds the two panels, is hardened by exposure to light. The sealant is irradiated from the thin film transistor array panel side because an opaque layer is usually formed on the opposite panel facing the gate-driving circuitry. Irradiating from the thin film transistor array panel side, however, may lead to insufficient light to harden the sealant, especially when the width of a signal line, or a transistor, in the gate-driving circuitry, is larger than 100 μm. Consequently, the two panels may be susceptible to moisture entered through the insufficiently cured sealant, leading to corrosion in the gate-driving circuitry. 
         [0006]    Accordingly, there is a need for a display device with gate driving circuitry that overcomes the disadvantages discussed above. 
       SUMMARY 
       [0007]    Devices and methods disclosed herein are applicable to thin film transistor array panels and display devices. For example, in accordance with an embodiment of the present invention, a display device includes a thin film transistor array panel, a counter panel, a sealant, and a liquid crystal layer, which is provided in the space enclosed by the thin film transistor array panel, the counter panel and the sealant. Gate-driving circuitry which includes signal lines and driving circuitry, may be formed directly on the thin film transistor array panel and overlapped at least in part by the sealant and an opaque region of the counter panel. 
         [0008]    An aperture may be formed on one or more signal lines, to allow light illuminating from the thin film transistor array panel side to easily pass, so as to facilitate the photoset sealant to harden. The signal lines may be formed as a ladder or a net-shaped structure. Such a ladder or net-shaped signal line may include vertical and horizontal branches between and connecting adjacent vertical branches. The width of a vertical or horizontal branch, or the width of the aperture,can be designed to facilitate light to pass through (e.g., about 20˜30 μm, preferably about 25 μm). The signal line structure described above is especially suited for a signal line that is more than 100 μm wide. 
         [0009]    The driving circuitry may include transistors connected in parallel and spaced apart to form one or more apertures among the transistors. The aperture width can be determined for easy light passage, e.g., about 20˜100 μm wide. 
         [0010]    With such apertures in the gate-driving circuitry, sufficient light is able to pass to harden the sealant, thereby holding the panels air-tight or moisture-tight. Consequently, the gate-driving circuitry can avoid corrosion by moisture from outside, and malfunctions in the gate-driving circuitry of the display device can be reduced. 
         [0011]    The scope of the invention is defined by the claims. A more complete description of the embodiments of the present invention and their advantages are provided in the following. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]      FIG. 1  is an exemplary layout view of a display device in accordance with an embodiment of the present invention. 
           [0013]      FIG. 2  is a cross-sectional view taken along the line II-II′ of  FIG. 1 . 
           [0014]      FIG. 3  is an exemplary block diagram of a shift register in the gate-driving circuitry, according to an embodiment of the present invention. 
           [0015]      FIG. 4  is an exemplary circuit implementation of a th stage of a j-th stageof the shift register of  FIG. 3 . 
           [0016]      FIG. 5  is an exemplary layout view of the gate-driving circuitry in accordance with an embodiment of the present invention. 
           [0017]      FIG. 6  is an exemplary layout view of the signal lines of the gate-driving circuitry of  FIG. 5 . 
           [0018]      FIG. 7  is a cross-sectional view taken along the line VII-VII′ of  FIG. 6 . 
           [0019]      FIG. 8  is an exemplary layout view of the driving circuitry of the gate-driving circuitry of  FIG. 5 . 
           [0020]      FIG. 9  is a cross-sectional view taken along the line IX-IX′ of  FIG. 8 . 
           [0021]      FIG. 10  is an exemplary layout view of a pixel in a display area. 
           [0022]      FIG. 11  is a cross-sectional view taken along the line XI-XI′ of  FIG. 10 . 
       
    
    
       [0023]    Like reference numerals are used to identify like elements in the figures. Furthermore, the elements or layers may not be drawn to scale and may be magnified for clarity (e.g., when illustrating semiconductor layers), Also, the words “above” or “on” may be used, for example, to refer to a position of a layer, an area, or a plate relative to another referenced element, but such use is not intended to exclude an intermediate element disposed between the referenced element and the layer, area, or plate. However, the terms “directly above” or “directly on” are used to indicate that no intermediate element exists between the referenced element and the layer, area, or plate. 
       DETAILED DESCRIPTION 
       [0024]      FIG. 1  is an exemplary layout view of a display device  600  in accordance with an embodiment of the present invention, and  FIG. 2  is a cross-sectional view taken along the line II-II′ of  FIG. 1 . As shown in  FIGS. 1 and 2 , display device  600  includes a display panel  300  displaying an image under control of the gate signals and data signals, which are provided by gate-driving circuitry  400  and data-driving circuitry  500 , respectively. The display area DA and the gate-driving circuitry  400  may be formed on a single substrate, such as substrate  110  of  FIG. 2 . 
         [0025]    The display panel  300  includes a thin film transistor array panel  100 , a counter panel  200  opposite the thin film transistor array panel  100 , a sealant  350  and a liquid crystal layer  330  provided in a space enclosed by the thin film transistor array panel  100 , counter panel  200  and sealant  350 . 
         [0026]    The display panel  300  may be divided into a display area DA, a sealant area SA enclosing the display area DA, a first peripheral area PA 1  outside the display area DA, and a second peripheral area PA 2  overlapping at least in part the display area DA and the sealant area SA. The thin film transistor array panel  100  covers the display area DA, the sealant area SA, and the peripheral areas PA 1  and PA 2 , while the counter panel  200  may not cover the first peripheral area PA 1 . 
         [0027]    An equivalent circuit for the display panel  300  includes gate lines GL 1 ˜GL n , data lines DL 1 ˜DL m  and pixels electrically connected to them. 
         [0028]    Gate lines GL 1 ˜GL n  and data lines DL 1 DL m  are formed on a first substrate  110 , insulated from and crossing each other on the display area DA, and extending to the second and first peripheral areas PA 2  and PA 1 , respectively. Gate lines GL 1 ˜GL n  and data lines DL 1 ˜DL m  are connected to the gate-driving circuitry  400  and the data-driving circuitry  500 , respectively. 
         [0029]    Each pixel includes a liquid crystal capacitance C lc , a thin film transistor Tr electrically connected to a corresponding gate line, and a corresponding data line. 
         [0030]    The thin film transistor Tr is formed on the thin film transistor array panel  100 , and includes a gate electrode connected to the gate line, a source electrode connected to the data line, and a drain electrode connected to the liquid crystal capacitance C lc . The thin film transistor Tr also includes an amorphous silicon (a-Si) or a polycrystalline silicon. 
         [0031]    The liquid crystal capacitance C lc  includes a pixel electrode (not shown) formed on the thin film transistor array panel  100 , a counter electrode  270  formed on a second substrate  210 , and the liquid crystal layer  330  disposed between the pixel electrode and the counter electrode  270 . The pixel electrode is electrically connected to the thin film transistor Tr, and the counter electrode  270  is electrically connected to a common voltage source. 
         [0032]    The data-driving circuitry  500  may be mounted as integrated-circuits on the first peripheral area PA 1  of the thin film transistor array panel  100 , instead of being provided on a printed circuit board (PCB). The data-driving circuitry  500  is electrically connected to the data lines DL 1 ˜DL m , which carry the data signals. 
         [0033]    The gate-driving circuitry  400  is formed on the second peripheral area PA 2  of the thin film transistor array panel  100  and is electrically connected to the gate lines GL 1 ˜GL n , which carry the gate signals. 
         [0034]    The sealant  350  is provided in the sealant area SA. The liquid crystal layer  330  is sealed and the two panels  100  and  200  are held in place by the sealant  350 . The sealant  350  includes a photosetting material. 
         [0035]    The sealant  350  overlaps at least in part the gate-driving circuitry  400 . The typical dielectric constant of the sealant  350  is about 4.0, compared with the 10.0 or more dielectric constant of the liquid crystal layer  330 . Therefore, parasitic capacitance between the gate-driving circuitry  400  and the counter electrode  270  can be significantly reduced. 
         [0036]    As shown in  FIG. 2 , the counter panel  200  may further include an opaque region  220  or a color filter layer (not shown) between the second substrate  210  and the counter electrode  270 . The color filter layer may be formed on the thin film transistor array panel  100 . 
         [0037]    The liquid crystal layer  330  can be introduced into the space enclosed by the thin film transistor array panel  100 , the counter panel  200  and the sealant  350  using a so-called one-drop-filling (ODF) method. In the ODF method, a liquid crystal drop is provided on either the thin film transistor array panel  100 , or the counter panel  200 , and the sealant  350  is provided on either the thin film transistor array panel  100  or the counter panel  200 . The sealant  350  is irradiated by light to be hardened, after alignment with the thin film transistor panel  100  and the counter panel  200  is performed. The light is provided from the side of the thin film transistor array panel  100 , so as not to be blocked by the opaque region  220 , which would have been the case if the sealant  350  is illuminated from the side of the counter panel  200 . 
         [0038]      FIG. 3  is an exemplary block diagram of a shift register of the gate driving portion  400  in accordance with an embodiment of the present invention.  FIG. 4  is an exemplary circuit implementation of one stage (e.g., a j-th stage) of the shift register of  FIG. 3 . 
         [0039]    As shown in  FIG. 3 , the gate-driving circuitry  400  includes n+1cascaded stages ST 1 ˜ST n−1 that are connected to respective gate lines G 1 ˜G n , except for the last stage ST n+1 . Also, as a shift register, the gate-driving circuitry  400  may receive the gate-off voltage V off , first and second clock signals CKV and CKVB, an initialization signal INT and a scan starting signal STV. 
         [0040]    Each stage may include a gate voltage terminal GV, first and second clock terminals CK 1  and CK 2 , a set terminal S, a reset terminal R, a frame reset terminal FR, a gate output terminal OUT 1 , and a carry output terminal OUT 2 . In each stage (e.g., the j-th stage ST j ), the set terminal receives the carry output C out (j−1) of the previous stage ST j−1 , while the reset terminal R receives the gate output G out (j+1) of the next stage ST j+1 . Also, the first and second clock terminals CK 1  and CK 2  receive the complementary first and second clock signals CKV and CKVB, respectively, and the gate voltage terminal GV receives the gate-off voltage V off . The stage provides gate output signal G out (j) at gate output terminal OUT 1  and a carry output signal C out (j) via the carry output terminal OUT 2 . (In this embodiment, the first and second clock signals CKV and CKVB have a 50% duty ratio and a 180° phase difference). 
         [0041]    The first stage of the shift register (i.e., ST 1 ) receives a scan starting signal STV. Successive stages receiver alternate phases of complementary clock signals CKV and CKVB. That is, if the first and second clock terminals CK 1  and CK 2  receive the first and second clock signals CKV and CKVB, respectively, in the j-th stage ST j , the first and second clock terminals CK 1  and CK 2  receive the second and first clock signals CKVB and CKV, respectively. 
         [0042]    In order to drive the thin film transistor Tr of the pixel, the high signals of the first and second clock signals CKV and CKVB may be the gate-on voltage V on , while the low signals of the first and second clock signals CKV and CKVB may be the gate-off voltage V off . 
         [0043]    Referring to  FIG. 4 , the j-th stage ST j of the gate-driving circuitry  400  includes an input circuit  420 , a pull-up driving circuit  430 , a pull-down driving circuit  440 , and an output circuit  450 . The j-th stage ST j includes transistors T 1 ˜T 15  (e.g., NMOS transistors), with the pull-up driving circuit  430  and the output circuit  450  further including capacitors C 1 ˜C 3 . Although NMOS transistors are illustrated, PMOS transistors or other types of transistors may be used instead of the NMOS transistors. Also, any of the capacitors C 1 ˜C 3  can be a parasitic capacitor between the gate and the drain/source terminals of a transistor, formed during manufacturing. 
         [0044]    In this embodiment, the input circuit  420  includes a set terminal S and three transistors T 5 , T 10  and T 11 , connected in series to the gate voltage terminal GV. The gates of the two transistors T 5  and T 11  are connected to the second clock terminal CK 2 , and the gate of transistor T 10  is connected to the first clock terminal CK 1 . The junction point between the transistor T 11  and the transistor T 10  is connected to the junction point J 1 , and the junction point between the transistor T 5  and the transistor T 10  is connected to the junction point J 2 . 
         [0045]    As shown in  FIG. 4 , pull-up driving circuit  430  includes a transistor T 4  between the set terminal S and junction point J 1 , a transistor T 12  between the first clock terminal CK 1  and the junction point J 3 , and the transistor T 7  between the first clock terminal CK 1  and the junction point J 4 . The gate and the drain of the transistor T 4  are commonly connected to the set terminal S, while the source is connected to the junction point J 1 . Similarly, the gate and the drain of the transistor T 12  are commonly connected to the first clock terminal CK 1 , while the source is connected to the junction point J 3 . 
         [0046]    The gate of the transistor T 7  is connected to both the junction point J 3  and the first clock terminal CK 1 . The drain of the transistor T 7  is connected to the first clock terminal CK 1 . The source of the transistor T 7  is connected to the junction point J 4 . The capacitor C 2  is located between the junction J 3  and the junction J 4 . 
         [0047]    Pull-down driving circuit  440  includes transistors T 6 , T 9 , T 13 , T 8 , T 3 , and T 2 , which have sources for receiving the gate-off voltage V off  and drains for transferring the gate-off voltage V off  to the junction points J 1 , J 2 , J 3 , and J 4 . The transistor T 9  has a gate connected to the reset terminal R, and a drain connected to the junction point J 1 . The transistors T 13  and T 8  have their gates commonly connected to the junction point J 2 , and their drains connected to the junction points J 3  and J 4 , respectively. The transistors T 2  and T 3  have gates connected to the junction point J 4  and to the reset terminal R, respectively, and a drain, which is commonly connected to the junction point J 2 . The transistor T 6  has a gate connected to the frame reset terminal FR and a drain connected to the junction point J 1 . 
         [0048]    The output circuit  450  may include a capacitor C 3  and two transistors T 1  and T 15 . The gates of the transistors T 1  and T 15  are commonly connected to the junction point J 1 , while their sources are connected to the first clock terminal CK 1 . The transistors T 1  and T 15  have their drains respectively coupled to the output terminals OUT 1  and OUT 2 . The capacitor C 3  is between the junction point J 1  and J 2 . The drain of the transistor T 1  is also connected to the junction point J 2 . 
         [0049]    Now the operation of the exemplary stage ST j  of  FIG. 4  is explained. The high voltage state of a signal is called a “high signal” throughout this specification; the low voltage state of a signal is called a “low signal” and may be substantially the same as the gate-off voltage V off . 
         [0050]    With the second clock signal CKVB and the previous carry output C out (j−1) both carrying a high signal, the transistors T 11 , T 5 , and T 4  are turned on. Then, the two transistors T 11  and T 4  transmit a high signal to the junction point J 1 , while the transistor T 5  transmits a low signal to the junction point J 2 . Thereafter, the transistors Ti and T 15  are turned on and the first clock signal CKV is transmitted to the output terminals OUT 1  and OUT 2 . 
         [0051]    Because the signal of the junction point J 2  and the first clock signal CKV are low signals, the output signals G out (j) and C out (j) are low signals; simultaneously, the capacitor C 3  is charged to the voltage difference between the high signal and the low signal. 
         [0052]    At this time, because the signal clock CKV, the next gate output G out (j+1) and the junction point J 2  are all low signals, the connected transistors T 10 , T 9 , T 12 , T 13 , T 8 , and T 2  all turn off. 
         [0053]    Subsequently, the transistors T 11  and T 5  turn off when the second clock signal CKVB is low; simultaneously, the output signal of the transistor T 1  and the signal of the junction point J 2  are high signals when the first clock signal CKV is a high signal. At this time, because the gate and the source of the transistor T 10  have high signals, the zero voltage difference turns off the transistor T 10 . Accordingly, the high signal of the capacitor C 3  is added to the floating junction point J 1 . 
         [0054]    The high signal of the first clock signal CKV and the junction point J 2  turn on the transistors T 12 , T 13  and T 8 . The directly connected transistors T 12  and T 13  are in voltages between the high signal and the low signal and determine the divided potential of the junction point J 3  according to the resistance of the turned on transistors T 12  and T 13 . 
         [0055]    Here, if the resistance of the transistor T 13  in its turn-on state is greater than that of the transistor T 12  in its turn-on state (e.g., 10,000 times greater), the voltage of the junction point J 3  is substantially the same as the high signal. Subsequently, the transistor T 7  is turned on, and the voltage of the junction point J 4  is determined by the turn-on resistance of the transistors T 7  and T 8 . 
         [0056]    With the transistors T 7  and T 8  having substantially the same resistance, the junction point J 4  has a voltage intermediate between the high signal and the low signal; thus, the transistor T 3  remains turned off. Also, the transistors T 9  and T 2  remain turned off because the next gate output G out (j+1) stays at low signal. 
         [0057]    Accordingly, the output terminals OUT 1  and OUT 2  transmit high signals by being isolated from a low signal and being connected to the first clock signal CKV. The capacitors Cl and C 2  are charged by the respective potential difference of their terminals, and the potential of the junction point J 3  is lower than the potential of the junction point J 5 . 
         [0058]    When the next gate output signal G out (j+1) and the second clock signal CKVB have high signals and the first clock signal CKV has a low signal, the transistors T 9  and T 2  are turned on and transmit low signals to the junction points J 1  and J 2 . The voltage of the junction point J 1  is lowered by discharging the capacitor C 3  to the low voltage. 
         [0059]    Accordingly, the two transistors T 1  and T 15  remain turned on for a time period after the next gate output G out (j+1) has a high signal; then, the output terminals OUT 1  and OUT 2  transmit low signals, being connected to the first clock signal CKV. 
         [0060]    Next, the carry output C out (j) is floating and remains a low signal because the output terminal OUT 2  is isolated from the first clock signal CKV by turning off the transistor T 15 , which results from the complete discharge of the capacitor C 3  and the low voltage of the junction point J 1 . Simultaneously, even when the transistor T 1  is turned off, the output terminal OUT 1  continuously transmits a low voltage because of the connection with the low signal via transistor T 2 . 
         [0061]    The junction point J 3  is isolated because the transistors T 12  and T 13  are turned off Also, the voltage of the junction point J 5  is lower than that of the junction point J 4 , and the transistor T 7  is turned off because the voltage of the junction point J 3  remains lower than that of the junction point J 5  by the voltage on capacitor C 1 . Simultaneously, due to the transistor T 8  being turned off, the voltage of the junction point J 4  is lowered. Also, the transistor T 10  remains turned off because its gate is connected to the low voltage of the first clock signal CKV and the signal of the junction point J 2  is low. 
         [0062]    Next, with the first clock signal CKV being high, the transistors T 12  and T 7  are turned on, and with the voltage of the junction point J 4  increasing, the transistor T 3  is turned on and transmits a low signal to the junction point J 2  to make the output terminal OUT 1  transmit the low signal. That is, even though the output of the next gate output G out (j+1) has a low signal, the voltage of the junction point J 2  may be a low signal. 
         [0063]    Having the gate connected to the high first clock signal CKV and low signal junction point J 2 , the transistor T 10  is turned on and transmits the low voltage of the junction point J 2  to the junction point J 1 . The sources of the transistors T 1  and T 15  receive the first clock signal CKV continuously because the sources are connected to the first clock terminal CK 1 . Furthermore, because the transistor T 1  is larger than the other transistors, the change of the source voltage can affect the gate voltage because of the large parasitic capacitance between the gate and the source in transistor T 1 . 
         [0064]    Therefore, with the high clock signal CKV, the transistor T 1  can be turned on due to the parasitic capacitance between its gate and its source. To prevent switching on the transistor T 1 , the gate signal of the transistor T 1  is maintained as a low signal by transmitting the low signal of the junction point J 2  to the junction point J 1 . 
         [0065]    Later on, until the previous carry output C out (j−1) attains a high voltage, the junction point J 1  maintains the low signal. The junction point J 2  maintains a low voltage via the transistor T 3  when the first clock signal CKV is a high voltage and the second clock signal CKVB is a low voltage; otherwise, with low first clock signal CKV and high second clock signal CKVB, the junction point J 2  maintains a low voltage via the transistor T 5 . 
         [0066]    Receiving an initialization signal INT from the carry output C out (n+1) of the last dummy stage ST n+1 , the transistor T 6  transmits the gate-off signal V off  to the junction point J 1 . 
         [0067]    As explained above, the j-th stage ST j  generates the carry signal C out (j) and the gate signal G out (j) based on the previous carry signal C out (j−1), the next gate signal G out (j+1), the first and second clock signals CKV and CKVB. 
         [0068]    An exemplary implementation of the gate-driving circuitry  400  is now explained in reference to  FIGS. 5, 6 and 8 .  FIG. 5  is an exemplary layout view of the gate-driving circuitry in accordance with an embodiment of the present invention.  FIG. 6  is an exemplary layout view of signal lines of the gate driving portion of  FIG. 5 .  FIG. 8  is an exemplary layout view of a driving circuitry of the gate-driving circuitry of  FIG. 5 . 
         [0069]    As shown in  FIG. 5 , the gate-driving circuitry  400  in accordance with an embodiment of the present invention includes a driving circuitry CS having cascaded stages ST 1 ˜ST n−1 , and a set of signal lines SL transmitting various signals, for example, V off , CKV, CKVB and INT to cascaded stages ST 1 ˜ST n+1 . 
         [0070]    The set of signal lines may include a gate-off signal line SL 1  transmitting the gate-off signal V off , first and second clock signal lines SL 2  and SL 3  transmitting first and second clock signals CKV and CKVB, respectively, and an initialization signal line SL 4  transmitting the initialization signal INT. The signal lines SL 1 ˜SL 4  extend vertically. The gate-driving circuitry  400  may further include bridge lines  172  ( 172   a ˜ 172   c  as in  FIG. 6 ) extending horizontally to the stages ST 1 ˜ST n−1 . 
         [0071]    In each stage, for example the (j−1)-th stage ST j−1 , of the driving circuitry CS, the transistor T 4  receiving the previous carry output C out (j−2) may be located near the previous stage ST j−2 , and the transistors T 1  and T 15  receiving the first clock signal CKV from the first clock signal line SL 2  may be located along the bridge line connected to the first clock signal line SL 2 . The transistors T 7 , T 10  and T 12  which also receive the first clock signal CKV are located near the bridge line connected to the first clock signal line SL 2 . The transistors T 11  and T 5  receiving the second clock signal CKVB from the second signal line SL 3  may be located along the bridge line connected to the second signal line SL 3 , and the transistor T 6  receiving the initialization signal INT from the initialization signal line SL 4  may be located leftmost. The transistors T 2 , T 3 , T 8 , T 9  and T 13  receiving the gate-off signal V off  from the gate-off signal line SL  1  are located along the bridge line connected to the gate-off signal line SL 1 . 
         [0072]    The layout of the transistors in the j-th stage ST j  is the same as in the above (j−1)-th stage ST j−1 , except that the first clock signal CKV and the first clock signal line SL 2  are interchanged with the second clock signal CKVB and the second clock signal line SL 3 , respectively. 
         [0073]    Signal lines SL and part of the driving circuitry CS are located in the sealant area SA, while the remaining part of the driving circuitry CS is located in a manufacturing marginal area SA′ of the seal area SA. The width of the manufacturing marginal area SA′ is currently about 0.3 mm, which is the maximum deviation from the target in disposing the sealant  350  on the seal area SA. 
         [0074]    As explained above, the signal lines and the transistors in the seal area SA or the manufacturing marginal area SA′ should be designed to allow sufficient light (Lg) from the first substrate  110  to pass through to harden the sealant  350 . 
         [0075]    As shown in  FIG. 6 , the wide signal lines such as SL 1 ˜SL 3  have a ladder or net-shaped structures  122   a ˜ 122   c  each having apertures through which light can easily pass. Accordingly, each signal line SL 1 ˜SL 3  may include a first group of branches extending vertically, a second group of branches between and connecting the branches of the first group, and apertures enclosed by the first and second groups of branches. Each branch or each aperture may be provided a predetermined width to allow light to easily pass through (e.g., about 20˜30 μm, and preferably about 25 μm). The total width of each of signal lines SL 1 ˜SL 3  may be determined from the increased resistance resulting from the apertures formed in it. For a signal line that is more than 100 μm wide, the structure described above has significant advantages. 
         [0076]    As shown in  FIG. 8 , a large transistor located in the sealant area SA or in the manufacturing marginal area SA′ (e.g., the transistor T 4  or T 15  of the  FIG. 5 ) includes smaller transistors connected in parallel and spaced apart from one another by apertures. The width of each smaller transistor or each aperture is provided such as to allow light to easily pass through (e.g., 100 μm or less). 
         [0077]    The structure of the thin film transistor array panel  100  including the gate-driving circuitry  400  is now explained in reference to  FIGS. 7 and 9-11  as well as  FIGS. 6 and 8 .  FIG. 7  is a cross-sectional view taken along the line VII-VII′ of  FIG. 6 .  FIG. 9  is a cross-sectional view taken along the line IX-IX′ of  FIG. 8 .  FIG. 10  is an exemplary layout view of a pixel in a display area.  FIG. 11  is a cross-sectional view taken along the line XI-XI′ of  FIG. 10 . 
         [0078]    Gate lines  121  and signal lines  122 ( 122   a ˜ 122   d ) of the gate-driving circuitry  400  are formed on the insulating substrate  110 . 
         [0079]    As shown in  FIG. 10 , the gate lines  121  extend horizontally to the gate-driving circuitry  400  and transmit the gate signals. Each of gate line  121  may include a gate electrode  124 , and, in another portion, may be projections  127 . 
         [0080]    As shown in  FIG. 6 , the signal lines  122   a˜   122   d  extend vertically and transmit the gate-off signal V off , the first and the second clock signals CKV and CKVB, and the initialization signal INT. Except for the narrowest one  122   d,  the signal lines  122   a ˜ 122   c  have ladder or net-shaped structures including long vertical branches, short horizontal branches between and connecting adjacent vertical branches, and apertures enclosed by the vertical and horizontal branches. Each branch or each aperture may have a predetermined width so that light can easily pass through, (e.g., about 20˜30 μm, and preferably about 25 μm). The total width of each signal line  122   a ˜ 122   c  may be determined from the increased resistance introduced by apertures formed in it. Such a structure is desirable for a signal line of more than 100 μm wide. 
         [0081]    As shown in  FIG. 8 , the signal lines  122  are electrically connected to the gates of the transistors of the driving circuitry. 
         [0082]    The gate lines  121  and the signal lines  122  are formed out of a low resistivity conductive layer (e.g., silver, a silver alloy, aluminum, an aluminum alloy, copper or a copper alloy). Additionally, the gate lines  121  and the signal lines  122  may have a multi-layered structure including an additional conductive layer, such as chrome, titanium, tantalum, molybdenum, or their alloys (e.g., MoW alloy), which have good chemical, physical and electrical contact properties with indium tin oxide (ITO) or indium zinc oxide (IZO). One example of the multi-layered structure for the gate lines  121  is Cr/Al—Nd alloy. The gate lines  121  and the signal lines  122  may be tapered about 30˜80° to the surface of the insulating substrate  110 . 
         [0083]    A gate insulating layer  140 , made of SiNx, for example, covers the gate lines  121  and the signal lines  122 . Linear semiconductors  151  or island type semiconductors  152  made of, for example, hydrogenated amorphous silicon, are formed on the gate insulating layer  140 . The linear semiconductor  151  extends vertically and has extension portions  154  toward the gate electrode  124 . Also, the linear semiconductor  151  widens near the crossing point with gate line  121  to cover the wide area of gate line  121 . As shown in  FIG. 8 , the island type semiconductor  152  is located on the gate electrode. 
         [0084]    On the semiconductor layer  151  and  152 , a linear or island type silicide or highly doped n+ hydrogenated amorphous silicon may be formed as ohmic contacts  161 ,  162  and  165 . The linear ohmic contact  161  includes the second protrusion  163 , which is located on the first extension portion  154  of the linear semiconductor  151  in conjunction with the island type ohmic contact  165 . The other island type ohmic contacts  162  are located on the island type semiconductor  152 . The ohmic contacts  161 ,  162  and  162  or the semiconductor  151  and  152  may be tapered about 30˜80° relative to the surface of the substrate  110 . 
         [0085]    Data lines  171 , output electrodes  175 , storage capacitor conductors  177 , and a bridge lines  172  ( 172   a    172   c ) are formed on the ohmic contacts  161 ,  162  and  165 , and the gate insulating layer  140 . As shown in  FIG. 10 , the data lines  171  extend vertically, crossing with the gate lines  121 , and transmit the data signals (e.g., data voltages). Branches, extended from each data line  171  to the output electrodes  175 , forms the input electrodes  173 . The input and output electrodes  173  and  175  in pair are separated and face each other across the gate electrode  124 . 
         [0086]    The storage capacitor conductor  177  overlaps the projection  127  of the gate line  121 . 
         [0087]    As shown in  FIG. 6 , the bridge line  172   a  may be formed between the gate-off signal line  122   a  and the first clock signal line  122   b,  and may include a vertical branch and horizontal branches extending to each stage. The bridge lines  172   b  and  172   c  may be formed between the first clock signal line  122   b  and the second clock signal line  122   c,  and may include a vertical branch and a horizontal branch extending to each stage. 
         [0088]    The data lines  171 , the output electrodes  175 , the bridge lines  172  and the storage capacitor conductors  177  are made of, for example, a low resistivity conductive layer of silver, a silver alloy, aluminum, an aluminum alloy, copper or a copper alloy. Additionally, the data lines  171 , the output electrodes  175  and the storage capacitor conductors  177  may have a multi-layered structure including an additional conductive layer of, for example, a refractory metal, such as molybdenum, chrome, titanium, tantalum, or their alloys (e.g. MoW ally). 
         [0089]    The lateral sides of the data line  171 , the output electrode  175 , the bridge lines  172  or the storage capacitor conductor  177  are tapered about 30˜80° to the surface of the substrate  110 . Linear or island type ohmic contacts  161 ,  162  and  165  are provided between the lower semiconductor  151  and  152  and the upper data lines  171 , the output electrode  175  or the bridge line  172  for reducing contact resistance. 
         [0090]    On the data lines  171 , the output electrodes  175 , the bridge lines  172 , the storage capacitor conductor  177 , and exposed semiconductor  151 , a passivation layer  180  can be made of, for example, an easily flattened and photosensitive organic material, a low dielectric (e.g., less than 4.0), insulating material such as a-Si:C:O or a-Si:O:F formed by plasma enhanced chemical vapor deposition (PECVD), or an inorganic material such as SiNx. The passivation layer  180  also may have a multi-layered structure including organic and inorganic layers. 
         [0091]    On the passivation layer  180 , contact holes  182 ,  185 ,  187  and  188  are formed to partially expose the area of the end portion  179  of the data lines  171 , the output electrode  175 , the storage capacitor conductor  177 , and the bridge line  172 . 
         [0092]    On the passivation layer  180 , an ITO or IZO layer of pixel electrodes  190 , contact assistants  82  and connection assistants  88  are formed. Through the contact holes  185  and  187 , the pixel electrodes  190  are connected to the output electrode  175  for receiving the data voltage, and connected to the storage capacitor conductor  177  for transmitting the data voltage. 
         [0093]    Liquid crystal molecules of the liquid crystal layer  330  are rearranged according to the electric field generated by the data voltage applied to the pixel electrode  190  and the common voltage applied to the counter electrode. Also, as explained above, the voltage difference between the pixel electrode  190  and the counter electrode  270  remains after the corresponding thin film transistor turns off. To increase the capacitance, an additional capacitor, called the storage capacitor C ST , may be provided in a parallel connection to the liquid crystal capacitor. 
         [0094]    The storage capacitor C ST  can be made by overlapping the pixel electrode  190  with its neighboring gate line. To enhance the storage capacitance, the gate line  121  can include extensional portion  127  for a wider overlapped area, and furthermore, the storage capacitor conductor  177 , connected to the pixel electrode and overlapped with the extensional portion  127 , may be located under the passivation layer  180 . Also, the pixel electrode  190  can be overlapped with the neighboring gate lines or data lines for a higher aperture ratio. 
         [0095]    The contact assistant  82 , which is optional, may be connected to the data lines end portion  179  via contact hole  182  to enhance a contact property with an external device and to protect the data lines end portion  179 . The auxiliary electrodes  88  may be connected to the signal lines  122  and the bridge lines  172  via contact holes  188  and  189 , respectively. Auxiliary electrode  88  need not be divided into smaller parts if the auxiliary electrode  88  is made of a transparent conductive metal through which light can easily pass. Moreover, the contact resistance decreases according to the size of the auxiliary electrode  88 . 
         [0096]    According to one or more embodiments of the present invention, transparent conductive polymer material can be used as the pixel electrode  190 . Alternatively, for reflective LCD, opaque reflective metal also can be used as the pixel electrode  190 . The contact assistant  82  can be made of a different material from the pixel electrode  190  such as ITO and/or IZO. 
         [0097]    According to one or more embodiments of the present invention, the signal lines  122  ( 122   a ˜ 122   d ) may be formed of the same layer as the data lines  171 , and the bridge lines  172  ( 172   a ˜ 172   c ) may be formed of the same layer as the gate lines  121 . 
         [0098]    Embodiments described above illustrate but do not limit the invention. Numerous modifications and variations are possible within the scope of the present invention. Accordingly, the scope of the invention is defined only by the following claims.