Abstract:
An apparatus for manufacturing a liquid crystal display (LCD) device includes a table receiving an LCD panel thereon, a first grinding part grinding a surface of the LCD panel to a first surface roughness, a second grinding part grinding the surface of the LCD panel grinded to the first surface roughness to a second surface roughness, wherein the second surface roughness is smoother than the first surface roughness, and a polishing part polishing the surface of the LCD panel which is grinded to the second surface roughness.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
   This application claims priority to Korean Patent Application No. 2006-0005672, filed on Jan. 19, 2006, the disclosure of which is incorporated herein by reference in its entirety. 
   BACKGROUND OF THE INVENTION 
   1. Technical Field 
   The present disclosure relates to an apparatus and a method for manufacturing a liquid crystal display (LCD) device, and more particularly, to an apparatus and a method for manufacturing a liquid crystal display (LCD) device having substrates with reduced thicknesses. 
   2. Discussion of the Related Art 
   An LCD device comprises an LCD panel including a first substrate where thin film transistors (TFTs) are formed, a second substrate facing the first substrate, and a liquid crystal layer interposed between the first and second substrates. 
   To reduce a thickness of the LCD panel, thicknesses of the first and second substrates can be reduced. However, if the first and second substrates are not thick enough initially, the substrates may be bent or damaged in a subsequent manufacturing process. Thus, to reduce the thickness of the LCD panel, the LCD panel is formed with substrates, whose thicknesses are reduced after the manufacturing process in which they may be bent or damaged. 
   An etching method and a wrapping method can be used to decrease the thickness of a glass substrate. The etching method uses an etching solution such as fluoric acid to decrease the thickness of the glass substrate. The wrapping method presses both surfaces of the glass substrate as a mother substrate at the same time to decrease the thickness of the glass substrate. 
   However, the etching method may cause a surface of the glass substrate to be coarse such that the light transmittance can be decreased. The etching method may cause the corrosion of signal wirings. Further, manufacture of the glass substrate can foe cumbersome with the etching method. Since the wrapping method is performed with the mother substrate, large-scaled equipment is used. Thus the manufacture of the LCD panel is cumbersome with the wrapping method. 
   SUMMARY OF THE INVENTION 
   An apparatus for manufacturing a liquid crystal display (LCD) device in accordance with an embodiment of the present invention, includes a table receiving an LCD panel thereon, a first grinding part grinding a surface of the LCD panel to a first surface roughness, a second grinding part grinding the surface of the LCD panel grinded to the first surface roughness to a second surface roughness which is smoother than the first surface roughness, and a polishing part polishing the surface of the LCD panel which is grinded to the second surface roughness. 
   The first grinding part and the second grinding part each may comprise a grinding head which grinds the surface of the LCD panel by friction, and the grinding head includes a diamond wheel to increase grinding intensity. 
   The first grinding part and the second grinding part each may comprise a grinding driving part which comprises a rotating driving member rotating the grinding head in parallel with the surface of the LCD panel and a revolving driving member revolving the grinding head in parallel with the surface of the LCD panel in order to grind the surface of the LCD panel uniformly. 
   The polishing part may include a polishing head polishing the surface of the LCD panel by friction with the surface of the LCD panel, and a polishing driving part which comprises a rotating driving member rotating the polishing head in parallel with the surface of the LCD panel and a revolving driving member revolving the polishing head in parallel with the surface of the LCD panel to grind the surface of the LCD panel uniformly. 
   The polishing part may include a first polishing part, and a second polishing part facing the first polishing part with the LCD panel interposed therebetween to improve a manufacturing efficiency of the LCD device by grinding both surfaces of the LCD panel at the same time. 
   The apparatus further may include a coupling part holding at least opposite edges of the LCD panel disposed between the first polishing part and the second polishing part. 
   The apparatus further may include a table rotating part sequentially carrying the LCD panel positioned on the table to the first grinding part, the second grinding part and the polishing part to reduce a movement distance. 
   The table may include at least one of a vacuum chuck and an electrostatic chuck which holds the LCD panel to prevent the LCD panel from moving in the process of grinding and polishing. 
   The apparatus may further include a reversely rotating part which turns the LCD panel with respect to an axis parallel to a surface of a floor. 
   The apparatus further may include a passivation layer forming part which forms a passivation layer along the edge of the LCD panel to prevent water or impurities from penetrating into a signal wiring and other components formed on a non-display region of the LCD panel and to prevent the signal wiring and the other components from, being corroding due to the water or impurities in the process of grinding or polishing. 
   The apparatus may further include a panel carrying part which positions the LCD panel on the table or removes the LCD panel from, the table. 
   A method for manufacturing an LCD device in accordance with an embodiment of the present invention, includes positioning an LCD panel on a table, grinding a first surface of the LCD panel to a first surface roughness, grinding the first surface of the LCD panel grinded to the first surface roughness to a second surface roughness which is smoother than the first surface roughness, and polishing the first surface of the LCD panel grinded to the second surface roughness. 
   The method may further include, after the polishing, turning the LCD panel, grinding a second surface of the LCD panel to a third surface roughness, grinding the second surface of the LCD panel grinded to the third surface roughness to a fourth surface roughness which is smoother than the third surface roughness, and polishing the second surface of the LCD panel grinded to the fourth surface roughness to reduce thickness of both surfaces of the LCD panel. 
   The method may further include forming a passivation layer along the edge of the LCD panel before grinding the first surface of the LCD panel to the first surface roughness, and removing the passivation layer after polishing the second surface of the LCD panel prevent water or impurities from penetrating into signal wiring and other components formed on a non-display region of the LCD panel and to prevent the signal wiring and the other components from being corroding due to the water or impurities in the process of grinding or polishing. 
   The method may further include turning the LCD panel between the polishing and the removing the passivation layer to facilitate removal of the passivation layer. 
   The method may further include cleaning and drying the LCD panel after the removing the passivation layer to remove water and impurities remaining in the LCD panel. 
   A method for manufacturing an LCD device in accordance with an embodiment of the present invention, includes positioning an LCD panel on a table, grinding a first surface of the LCD panel to a first surface roughness, grinding the surface of the LCD panel grinded to the first surface roughness to a second surface roughness which is smoother than the first surface roughness, turning the LCD panel, grinding a second surface of the LCD panel to a third surface roughness, grinding the second surface of the LCD panel grinded to the third surface roughness to a fourth surface roughness which is smoother than the third surface roughness, and polishing the first and second surfaces of the LCD panel. 
   The method may further include forming a passivation layer along the edge of the LCD panel before the grinding the first surface of the LCD panel to the first surface roughness, and removing the passivation layer after polishing the first and second surfaces of the LCD panel. 
   The method may further include turning the LCD panel between polishing and removing the passivation layer to facilitate removal of the passivation layer. 
   The polishing can be performed on the first and second surfaces of the LCD panel at the same time. 
   The method may further include cleaning and drying the LCD panel after the removing the passivation layer to remove water and impurities remaining in the LCD panel. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Exemplary embodiments of the present invention can be understood in more detail from the following description taken in conjunction with the accompanying drawings of which: 
       FIG. 1  is a plan view of an apparatus for manufacturing an LCD device according to an embodiment of the present invention; 
       FIG. 2  is a perspective view of a first grinding part of the apparatus according to an embodiment of the present invention; 
       FIG. 3  is a perspective view of a polishing part of the apparatus according to an embodiment of the present invention; 
       FIG. 4  is a perspective view to illustrate a method of manufacturing an LCD device according to an embodiment of the present invention; 
       FIG. 5  is a plan view of an apparatus for manufacturing an LCD device according to an embodiment of the present invention; 
       FIG. 6  is a perspective view of a polishing part of the apparatus according to an embodiment of the present invention; and 
       FIG. 7  is a perspective view to illustrate a method of manufacturing an LCD device according to an embodiment of the present invention. 
   

   DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
   Exemplary embodiments of the present invention will be described in more detail with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. 
   An apparatus for manufacturing an LCD device according to an embodiment of the present invention is described with reference to  FIGS. 1 through 3 .  FIG. 1  is a plan view of an apparatus for manufacturing an LCD device according to an embodiment of the present invention.  FIG. 2  is a perspective view of a first grinding part of the apparatus according to an embodiment of the present invention.  FIG. 3  is a perspective view of a polishing part of the apparatus according to an embodiment of the present invention. 
   An apparatus  1  for manufacturing an LCD device according to an embodiment of the present invention comprises a panel injecting part  100 , a passivation layer forming part  150 , a first panel carrying part  200 , a table  250 , a table rotating part  300 , a first grinding part  400 , a second grinding part  450 , a polishing part  500 , a second panel carrying part  600 , a reversely rotating part  700 , and a panel ejecting part  900 . 
   An LCD panel  10  is carried from the outside and is initially positioned on the panel injecting part  100 . The LCD panel  10  may comprise, for example, a glass substrate or a quartz substrate. 
   The passivation layer forming part  150  is provided at one lateral side of the panel injecting part  100 . The passivation layer forming part  150  forms a passivation layer  16  (see (b) in  FIG. 4 ) along the edge of the LCD panel  10  which is conveyed by a carrier (not shown) from the panel injecting part  100 . 
   The passivation layer forming part  150  comprises a passivation layer forming member  151  and an arranging part  158 . 
   The LCD panel  10  is positioned on the arranging part  158  to correspond to the passivation layer forming member  151 . The passivation layer forming member  151  jets a passivation layer forming solution  17  (see (a) in  FIG. 4 ) and cures the passivation layer forming solution  17  to form the passivation layer  16  comprising silicon. 
   The passivation layer forming member  151  moves along the edge of the LCD panel  10  to let the passivation layer forming solution  17  comprising silicon and a curing agent. The passivation layer forming member  151  moves along the edge of the LCD panel  10  to cure the passivation layer forming solution  17  to form the passivation layer  16 . 
   The passivation layer  16  prevents moisture or impurities from penetrating into a signal wiring (not shown) formed in the edge of the LCD panel  10  while the LCD panel  10  is grinded and polished to decrease the thickness of the LCD panel  10 . The passivation layer  16  is removed from the LCD panel  10  after finishing polishing the LCD panel  10 . 
   The first panel carrying part  200  is disposed near the passivation layer forming member  151  and carries the LCD panel  10  with the passivation layer  16  from the arranging part  158  to the table  250 . The first panel carrying part  200  comprises an absorbing part  210 , a connecting bar  220  and a rotary motor  230 . 
   The absorbing part  210  absorbs the LCD panel  10  for carrying the LCD panel  10  with the passivation layer  16  from the arranging part  158  to the table  250 . 
   The rotary motor  230  is connected to the absorbing part  210  through the connecting bar  220 . The rotary motor  230  rotates the absorbing part  210  to supply driving power to carry the LCD panel  10 , held by the absorbing part  210 , from the arranging part  158  to the table  250 . 
   The LCD panel  10  with the passivation layer  16  is positioned on the table  250 . The table  250  comprises a rotating plate  252  and a seating part  254 . 
   The rotating plate  252  is clockwise rotated by 90 degrees using the table rotating part  300  connected to the center of the rotating plate  252 . 
   The seating part  254  is formed on the rotating table  252 . The LCD panel  10  with the passivation layer  16  is substantially positioned on the seating part  254  of the table  250 . A vacuum chuck  256  is formed on the seating part  254  to prevent the LCD panel  10  positioned on the seating part  254  from moving while the LCD panel  10  is grinded and polished. In an embodiment of the present invention, the vacuum chuck  256  or an electrostatic chuck can be used to hold the LCD panel  10 . 
   The seating part  254  comprises a first seating part  254   a , a second seating part  254   b , a third seating part  254   c  and a fourth seating part  254   d . The seating parts  254   a ,  254   b ,  254   c  and  254   d  can be rotated 90 degrees in a clockwise direction to change positions. Thus, the LCD panel  10  positioned on each of the seating parts  254   a ,  254   b ,  254   c  and  254   d  is rotated to be grinded and polished while sequentially moving to the first grinding part  400 , the second grinding part  450  and the polishing part  500 . 
   The table rotating part  300  disposed in the center of the rotary table  252  comprises a shaft  310  and a rotating plate connecting part  320 . 
   The shaft  310  transmits rotatory power to the rotating plate  252  through the rotating plate connecting part  320  using a driving part such as a motor. The rotating plate  252  can foe rotated 90 degrees in a clockwise direction using the shaft  310 . 
   The first grinding part  400  extends from a lateral side of the second seating part  254   b  over the second seating part  254   b . The first grinding part  400  comprises a grinding head  410  and a grinding driving part  420 . The first grinding part  400  grinds a surface of the LCD panel  10  positioned on the second seating part  254   b  to a first surface roughness to decrease the thickness of the LCD panel  10 . 
   The grinding head  410  comprises a first diamond wheel  412  on the lower surface. The first diamond wheel  412  generates grinding power by friction with one of surfaces of the LCD panel  10  positioned on the second seating part  254   b.    
   The grinding driving part  420  comprises a rotating driving member  422 , a revolving driving member  424 , and a connecting part  425  connecting the rotating driving member  422  and the revolving driving member  424 . 
   The rotating driving member  422  such as, for example, a rotary motor is disposed on the center of the grinding head  410 . The rotating driving member  422  supplies driving power so that the grinding head  410  rotates in parallel with the surface of the LCD panel  10  to grind the LCD panel  10  by friction. 
   The revolving driving member  424  is connected to the rotating driving member  422  through the connecting part  425 . The revolving driving member  424  comprises a revolving part  424   a  and a revolution guide groove  424   b . The revolving part  424   a  revolves around the revolution guide groove  424   b  by a driving part (not shown) in parallel with the surface of the LCD panel  10 . Thus, the grinding head  410  is rotated by the rotating driving member  422  and revolved by the revolving driving member  424  at the same time to grind the entire surface of the LCD panel  10  to the first surface roughness by friction. As a result, the thickness of the LCD panel  10  can be reduced. 
   The apparatus  1  for manufacturing the LCD device may further comprise a coolant supplier (not shown). The coolant supplier provides cooling liquid to the first grinding part  400  and the surface of the LCD panel  10  to prevent temperature increase in the grinding head  410  of the first grinding part  400  and the surface of the LCD panel  10 . The temperature increase in the grinding head  410  can be caused by friction while grinding the LCD panel  10 . 
   The second grinding part  450  is disposed on one lateral side of the first grinding part  400 . 
   The LCD panel  10  grinded to the first surface roughness is carried by the table rotating part  300  to be disposed on the third seating part  254   c . Then, the second grinding part  450  grinds the surface of the LCD panel  10  to a second surface roughness. The second surface roughness is smoother than the first surface roughness. Accordingly, a thickness of the LCD panel  10  may further decrease. 
   The second grinding part  450  comprises a grinding head  460  and a grinding driving part  470 . 
   The grinding head  460  comprises a second diamond wheel (not shown). The second diamond wheel grinds the LCD panel  10 , having the first surface roughness, to the second surface roughness by friction with the surface of the LCD panel  10 . The second diamond wheel supplies lower grinding power than the first diamond wheel, so that the second surface roughness is less than the first surface roughness. 
   The grinding driving part  470  comprises a rotating driving member  472  and a revolving driving member  474 . Thus, the grinding head  460  is rotated by the rotating driving member  472  and revolved by the revolving driving member  474  at the same time to grind the entire surface of the LCD panel  10  to the second surface roughness. 
   The apparatus  1  for manufacturing the LCD device may further comprise a coolant supplier (not shown) to provide cooling liquid to the second grinding part  450  and the surface of the LCD panel  10 . 
   The polishing part  500  extends from one lateral side of the fourth seating part  254   d  over the fourth seating part  254   d . The polishing part  500  flattens the surface of the LCD panel  10 , which is grinded to the second surface roughness and then carried by the table rotating part  300 . The polishing part  500  polishes the surface of the LCD panel to increase light transmittance. 
   The polishing part  500  comprises a polishing head  510  and a polishing driving part  520 . 
   The polishing head  510  polishes the surface of the LCD panel  10  having the second surface roughness to remove the second surface roughness, thereby flattening the surface of the LCD panel  10  and increasing the light transmittance thereof. The thickness of the LCD panel  10  decreases further by polishing the LCD panel  10 . The polishing head  510  may comprise, for example, metal or cesium oxide (CeO). 
   The polishing driving part  520  comprises a rotating driving member  522 , a revolving driving member  524  and a connecting part  525  connecting the rotating driving member  522  and the revolving driving member  524 . 
   The rotating driving member  522  comprises a shaft  522   a  which transmits rotatory power from a motor  522   b  coupled by a motor coupling part  522   c  to the polishing head  520 . 
   The revolving driving member  524  comprises a revolving part  524   a  and a revolution guide groove  524   b . Thus, the polishing head  510  is rotated by the rotating driving member  522  and revolved by the revolving driving member  524  at the same time to polish the entire surface of the LCD panel  10  to be uniform. As a result, the thickness of the LCD panel  10  can be reduced. 
   The apparatus  1  for manufacturing the LCD device may further comprise a slurry supplier (not shown). The slurry supplier provides slurry to the surface of the LCD panel  10  to prevent temperature increase in the polishing head  500  and the surface of the LCD panel  10 . The temperature increase can be caused by friction while polishing the LCD panel  10 . The slurry supplier provides slurry to the surface of the LCD panel  10  to efficiently polish the LCD panel  10 . 
   The second panel carrying part  600  is provided in one lateral side of the fourth seating part  254   d . The second panel carrying part  600  comprises an absorbing part  610 , a connecting bar  620  and a shaft  630 . 
   The second panel carrying part  600  carries the LCD panel  10  positioned on the fourth seating part  254   d  to the reversely rotating part  700 . The reversely rotating part  700  comprises a clamp  710  and a rotating shaft  730 . After one surface of the LCD panel  10  is grinded and polished, the reversely rotating part  700  turns the LCD panel  10  to grind and polish the other surface of the LCD panel  10 . Further, when both substrates of the LCD panel  10  are grinded and polished, the reversely rotating part  700  turns the LCD panel  10  so that a smaller counter substrate  14  (see  FIG. 4 ) of the LCD panel  10  faces upward to facilitate removal of the passivation layer  16  from the LCD panel  10 . 
   The clamp  710  clamps opposite lateral sides of the LCD panel  10  to securely support the LCD panel  10  while turning the LCD panel  10 . The LCD panel  10  rotates by 180 degrees with respect to the rotating shaft  710 . The rotating shaft  710  can be rotated by the driving part (not shown) while being clamped. 
   When the reversely rotating part  700  turns the LCD panel  10  to facilitate the removal of the passivation layer  16 , the LCD panel  10  is carried to the panel ejecting part  900 . Then, the passivation layer  16  is removed from the LCD panel  10 . Then the LCD panel  10  is cleaned and dried before being ejected to the outside. 
   When the reversely rotating part  700  turns the LCD panel  10  to grind and polish the other surface of the LCD panel  10 , the LCD panel  10  is carried near the first seating part  254   a  along a guide rail  750 . The carried LCD panel  10  is positioned on the first seating part  254  by the first panel carrying part  200  to grind and polish the other surface thereof in a subsequent process. 
   The panel ejecting part  900  is disposed near the reversely rotating part  700 . After grinding and polishing both surfaces of the LCD panel  10  while being re-turned by the reversely rotating part  700 , the panel ejecting part  900  removes the passivation layer  16  from the LCD panel  10 . The LCD panel  10  is then cleaned and dried. Then the LCD panel  10  is ejected to the outside. 
   The apparatus  1  for manufacturing the LCD device according to an embodiment of the present invention can decrease the thickness of the LCD panel  10 . According to an embodiment of the present invention, a coarse surface of the glass substrate and a corrosion of signal wirings can foe prevented. As compared with the wrapping method, the apparatus  1  can use smaller-sized equipment to facilitate carrying and treatment of the LCD panel  10 , and may perform a continuous process to reduce manufacturing time. 
   A method for manufacturing an LCD device according to an embodiment of the present invention is described with reference to  FIGS. 1 through 4 .  FIG. 4  is a perspective view to sequentially illustrate a method for manufacturing an LCD device according to an embodiment of the present invention. 
   A method for manufacturing an LCD device according to an embodiment of the present invention is described as follows. The LCD panel  10  is positioned on the panel injecting part  100  in such a manner that a counter substrate  14  of the LCD panel  10  which is smaller than a TFT substrate  12  thereof faces upward. The LCD panel  10  is carried from the panel injecting part  100  to the arranging part  158  of the passivation layer forming member  150 . The passivation layer forming member  150  jets the passivation layer forming solution  17  along the edge of the LCD panel  10  and cures the passivation layer forming solution  17  to form the passivation layer  16 , as shown in (a) of  FIG. 4 . 
   The first panel carrying part  200  carries the LCD panel  10  with the passivation layer  16  from the arranging part  158  to the first seating part  254   a  of the table  250  on which the LCD panel is positioned. The rotating plate  252  of the table  250  is rotated by 90 degrees by rotation of the shaft  310  of the table rotating part  300 , so that the first seating part  254   a  moves to the position where the second seating part  254   b  was originally disposed. 
   Referring to (b) of  FIG. 4 , the first grinding part  400  grinds the surface of the counter substrate  14  of the LCD panel  10 , positioned on the first seating part  254   a  and having a thickness of d 1 , to the first surface roughness. Then, the counter substrate  14  has a thickness of d 2 , which is smaller than d 1 , as shown in (c) of  FIG. 4 . The rotating plate  252  of the table  250  is further rotated by 90 degrees by rotation of the shaft  310  of the table rotating part  300 , so that the first seating part  254   a  moves to the position where the third seating part  254   b  was originally disposed. 
   Referring to (c) of  FIG. 4 , the second grinding part  450  grinds the surface of the counter substrate  14  of the LCD panel  10 , positioned on the first seating part  254   a  and having the thickness of d 2  and the first surface roughness, to the second surface roughness. The second surface roughness is smoother than the first surface roughness. Then, the counter substrate  14  has a thickness of d 3 , which is smaller than d 2 , as shown in (d) of  FIG. 4 . 
   The first grinding part  400  may control grinding time or/and grinding intensity, thereby causing the counter substrate  14  to have various thicknesses. Further, the second grinding part  450  may control grinding time or/and grinding intensity, thereby causing the counter substrate  14  to have various thicknesses. Consequently, the counter substrate  14  may have various thicknesses. 
   If the counter substrate  14  is grinded independently of the first surface roughness and of the second surface roughness, the counter substrate  14  can be polished with reduced time. 
   Thereafter, the rotating plate  252  of the table  250  is rotated by 90 degrees by rotation of the shaft  310  of the table rotating part  300 , so that the first seating part  254   a  moves to the position where the fourth seating part  254   d  was originally disposed. 
   Referring to (d) of  FIG. 4 , the polishing part  500  polishes the surface of the counter substrate  14  having the thickness of d 3  and the second surface roughness. Then, the counter substrate  14  has a thickness of d 4 , which is smaller than d 3 , as shown in (i) of  FIG. 4 . 
   The polished LCD panel  10  is carried to the reversely rotating part  700  by the second panel carrying part  600 . The reversely rotating part  700  turns the LCD panel  10  so that the TFT substrate  12  faces upward, as shown in (e) of  FIG. 4 . The LCD panel  10  moves to one lateral side of the first panel carrying part  200  as the reversely rotating part  700  moves along the guide rail  750 . The rotating plate  252  of the table  250  is rotated by 90 degrees by rotation of the shaft  310  of the table rotating part  300 , so that the first seating part  254   a  returns to the original position. Accordingly, the LCD panel  10  with the TFT substrate  12  facing upward is positioned on the first seating part  254   a  by the first panel carrying part  200 . 
   Then, the rotating plate  252  of the table  250  is rotated by 90 degrees by rotation of the shaft  310  of the table rotating part  300 . Referring to (f) of  FIG. 4 , the first grinding part  400  grinds the surface of the TFT substrate  12 , positioned on the first seating part  254   a  and having a thickness of d 5 , to a third surface roughness. Then, the TFT substrate  12  has a thickness of d 6 , which is smaller than d 5 , as shown in (g) of  FIG. 4 . The third surface roughness is substantially similar, for example equal, to the first surface roughness of the counter substrate  14 . The rotating plate  252  of the table  250  is rotated by 90 degrees by rotation of the shaft  310  of the table rotating part  300 , so that the first seating part  254   a  moves to the position where the third seating part  254   c  was originally disposed. 
   Referring to (g) of  FIG. 4 , the second grinding part  450  grinds the surface of the TFT substrate  12 , positioned on the first seating part  254   a  and having the third surface roughness and the thickness of d 6 , to a fourth surface roughness. The fourth surface roughness is smoother than the third surface roughness. Then, the TFT substrate  12  has a thickness of d 7 , which is smaller than d 6 , as shown in (h) of  FIG. 4 . The fourth surface roughness is substantially similar, for example equal, to the second surface roughness of the counter substrate  14 . 
   The first grinding part  400  may control grinding time or/and grinding intensity, thereby causing the TFT substrate  12  to have various thicknesses. Further, the second grinding part  450  may control grinding time or/and grinding intensity, and thus the TFT substrate  12  may have various thicknesses. Consequently, the TFT substrate  12  may have various thicknesses. 
   Then, the rotating plate  252  of the table  250  is rotated by 90 degrees by rotation of the shaft  310  of the table rotating part  300 , so that the first seating part  254   a  moves to the position where the fourth seating part  254   d  was originally disposed. 
   Referring to (h) of  FIG. 4 , the polishing part  500  polishes the surface of the TFT substrate  12  having the fourth surface roughness and the thickness of d 7 . Then, the TFT substrate  12  has a thickness of d 8 , which is smaller than d 7 , as shown in (i) of  FIG. 4 . 
   Thereafter, the second panel carrying part  600  carries the LCD panel  10  to the reversely rotating part  700 . Then, the reversely rotating part  700  turns the LCD panel  10  so that the counter substrate  14  faces upward to facilitate removal of the passivation layer  16 . The reversely rotating part  700  carries the turned LCD panel  10  to the panel ejecting part  900  to remove the passivation layer  16 , as shown in (j) of  FIG. 4 . Then, a cleaning member  850  cleans the LCD panel  10  as shown in (k) of  FIG. 4 , and a drying member (not shown) dries the LCD panel  10  to finish decreasing the thickness of the LCD panel  10 . 
   In an embodiment, thicknesses of both substrates  12  and  14  of the LCD panel  10  are reduced by being grinded and polished. In an embodiment, one surface of respective substrates  12  and  14  is grinded and polished by the first grinding part  400 , the second grinding part  450  and the polishing part  500 . Then the passivation layer  16  is removed, and the LCD panel  10  is cleaned and dried. 
   An apparatus for manufacturing an LCD device according to an embodiment of the present invention is described with reference to  FIGS. 5 and 6 . 
     FIG. 5  is a plan view of an apparatus for manufacturing an LCD device according to an embodiment of the present invention.  FIG. 6  is a perspective view of a polishing part of the apparatus for manufacturing the LCD device according to an embodiment of the present invention. 
   An apparatus  2  for manufacturing an LCD device according to an embodiment comprises a polishing part  501  having a first polishing part  503  and a second polishing part  504  so that both surfaces of an LCD panel  10  may be polished at the same time. The second polishing part  504  is disposed opposite the first polishing part  503  with the LCD panel  10  interposed therebetween. The polishing part  501  may move toward or away from a coupling part  800 . 
   The first polishing part  503  and the second polishing part  504  comprise respective polishing heads  510  and  530 , respective rotating driving members  522  and  542 , and respective revolving driving members (not shown). 
   It is difficult for the first polishing part  503  and the second polishing part  504  to polish both surfaces of the LCD panel  10  while the LCD panel is positioned on a seating part  254  of a table  250 . Thus, the coupling part  800  holding opposite edges of the LCD panel  10  is provided near a second panel carrying part  600 . 
   The coupling part  800  comprises a pair of bodies  810  which may be disposed close to or far from each other, and grooves  820  to accommodate the opposite edges of the LCD panel  10 . The opposite edges of the LCD panel  10  carried by the second panel carrying part  600  from a fourth seating part  254   d  are inserted and fixed into the grooves  820 . 
   A method for manufacturing an LCD device according to an embodiment of the present invention is described with reference  FIGS. 5 through 7 .  FIG. 7  is a perspective view to sequentially illustrate a method for manufacturing an LCD device according to an embodiment of the present invention. 
   The operations of forming a passivation layer  16  along the edge of the LCD panel  10 , grinding the counter substrate  14  of the LCD panel  10  by the first grinding part  400  to the first surface roughness, and grinding the counter substrate  14  by the second grinding part  450  to the second surface roughness, as shown in (a) through (c) of  FIG. 4  are substantially similar to the operations as shown in (a) through (c) of  FIG. 7 . 
   A thickness of the counter substrate  14  grinded to the first surface roughness decreases from d 1  shown in (b) of  FIG. 7  to d 2  shown in (c) of  FIG. 7 . A thickness of the counter substrate  14  grinded to the second surface roughness decreases from d 2  shown in (c) of  FIG. 7  to d 3  shown in (d) of  FIG. 7 . 
   A rotating plate  252  is rotated by 90 degrees, and then a second panel carrying part  600  carries the LCD panel  10  to a reversely rotating part  700  without polishing the counter substrate  14 . The reversely rotating part  700  turns the LCD panel  10  such that the TFT substrate  12  faces upward, as shown in (e) of  FIG. 7 . The LCD panel  10  is moved near the first panel carrying part  200  along the guide rail  750  and is positioned on the first seating part  254   a.    
   Referring to (f) and (g) of  FIG. 7 , the first grinding part  400  and the second grinding part  450  grind the surface of the TFT substrate  12  to a third surface roughness and a fourth surface roughness, respectively. A thickness of the TFT substrate  12  grinded to the third surface roughness decreases from d 5  shown in (f) of  FIG. 7  to d 6  shown in (g) of  FIG. 7 . A thickness of the TFT substrate  12  grinded to the fourth surface roughness decreases from d 6  shown in (g) of  FIG. 7  to d 7  shown in (h) of  FIG. 7 . 
   The third surface roughness and the fourth surface roughness are substantially similar, for example equal, to the first surface roughness and the second surface roughness, respectively. 
   The rotating plate  252  is rotated by 90 degrees, and then the second panel carrying part  600  carries the LCD panel  10 , which is completely grinded to the fourth surface roughness, to the coupling part  300  to hold the LCD panel  10 . The first polishing part  503  and the second polishing part  504  polish both surfaces of the LCD panel  10 , which is interposed therebetween and held by the coupling part  800 , at the same time, as shown in (i) of  FIG. 7 . 
   The second panel carrying part  600  carries the LCD panel  10  with polished surfaces to the reversely rotating part  700 . The reversely rotating part  700  turns the LCD panel  10  so that the counter substrate  14  faces upward to facilitate removal of the passivation layer  16 , as shown in (j) of  FIG. 7 . The reversely rotating part  700  carries the LCD panel  10  to the panel ejecting part  900  to remove the passivation layer  16 , as shown in (k) of  FIG. 7 . A cleaning member  850  cleans the LCD panel  10  as shown in (j) of  FIG. 7 , and a drying member (not shown) dries the LCD panel  10 . 
   The method for manufacturing the LCD device using the apparatus  2  for manufacturing the LCD device according to an embodiment of the present invention causes the thicknesses of both substrates  12  and  14  to be reduced in less time than with conventional methods. 
   In exemplary embodiments, more than one of the first grinding part  400 , the second grinding part  450 , the polishing part  500  and the coupling part  800  can be used. 
   Although exemplary embodiments have been described with reference to the accompanying drawings, it is to be understood that the present invention is not limited to these precise embodiments but various changes and modifications can be made by one skilled in the art without departing from the spirit and scope of the present invention. All such changes and modifications are intended to be included within the scope of the invention as defined by the appended claims.