Active matrix type liquid crystal display device and method of manufacturing the same

Abstract

In an active matrix type liquid crystal display device in which a common electrode and a second pixel electrode have portions opposing each other, and an electric field parallel to substrates is formed between the two electrodes, Y direction extending portions of the common electrode are provided above data lines via a second interlayer insulation film. Slits are opened in the Y direction extending portions of the common electrode along the data lines. Portions of a black matrix which are set to a common electric potential with tie common electrode arc provided on an opposing substrate at positions opposing the slits.

What is claimed is:  
     
         1 . An active matrix type liquid crystal display device comprising: 
 a pair of substrates;    a liquid crystal sealed between said pair of substrates;    a plurality of data lines and a plurality of scanning lines which are arranged so as to intersect each other on one surface of one of said pair of substrates;    a switching element having an electric current path one end of which is connected to corresponding one of said data lines, and having a control terminal which is connected to corresponding one of said scanning lines;    a pixel electrode which is provided above said data lines via an insulation film, and is connected to the other end of the electric current path of said switching element; and    a common electrode which opposes to said data lines via said insulation film, has slits in portions overlapping said data lines, to generate an electric field between said pixel electrode.    
     
     
         2 . The active matrix type liquid crystal display device according to  claim 1 , wherein: 
 said common electrode and said pixel electrode respectively have linear portions which oppose with each other almost in parallel by a predetermined length;    said overlapping portions are provided along said linear portions; and    said slits have a length which is almost the same as that of said liner portions.    
     
     
         3 . The active matrix type liquid crystal display device according to  claim 1 , wherein 
 said slits are formed in almost a center of a width of said overlapping portions.    
     
     
         4 . The active matrix type liquid crystal display device according to  claim 1 , wherein 
 said overlapping portions of said common electrode have a width equal to or wider than that of said data lines.    
     
     
         5 . The active matrix type liquid crystal display device according, to  claim 1 , wherein 
 said slits have a width smaller than that of said data lines.    
     
     
         6 . The active matrix type liquid crystal display device according to  claim 1 , wherein 
 said common electrode and said pixel electrode are on a same plane.    
     
     
         7 . The active matrix type liquid crystal display device according to  claim 1 , wherein 
 said common electrode aid said pixel electrode are made of a transparent conductive material.    
     
     
         8 . The active matrix type liquid crystal display device according to  claim 1 , wherein 
 said common electrode and said pixel electrode are on different planes respectively.    
     
     
         9 . The active mats type liquid crystal display device according to  claim 1 , wherein 
 an electric field in a direction parallel to said pair of substrates is formed between said common electrode and said pixel electrode.    
     
     
         10 . An active matrix type liquid crystal display device comprising: 
 a pair of substrates;    a liquid crystal sealed between said pair of substrates;    a plurality of data lines and a plurality of scanning lines which are arranged so as to intersect each other on one surface of one of said pair of substrates;    a switching element having an electric current path one end of which is connected to corresponding one of said data lines, and having a control terminal which is connected to corresponding one of said scanning lines;    a pixel electrode which is provided above said data lines via an insulation film, and is connected to the other end of the electric current path of said switching element;    a common electrode which opposes to said data lines via said insulation film, has slits in portions overlapping said data lines, to generate an electric field between said pixel electrode; and    a first conductive film which is provided on the other of said pair of substrates so as to oppose to said data lines via said slits, and is set to a common electric potential with said common electrode.    
     
     
         11 . The active matrix type liquid crystal display device according to  claim 10 , wherein: 
 said common electrode and said pixel electrode respectively have linear portions which oppose with each other almost in parallel by a predetermined length;    said overlapping portions are provided along said linear portions; and    said slits have a length which is almost the same as that of said liner portions.    
     
     
         12 . The active matrix type liquid crystal display device according to  claim 10 , wherein 
 said slits are formed in almost a center of a width of said overlapping portions.    
     
     
         13 . The active matrix type liquid crystal display device according to  claim 10 , wherein 
 said overlapping portions of said common electrode have a width equal to or wider than that of said data lines.    
     
     
         14 . The active matrix type liquid crystal display device according to  claim 10 , wherein 
 said slits have a width smaller than that of said data lines.    
     
     
         15 . The active matrix type liquid crystal display device according to  claim 10 , wherein 
 said common electrode and said pixel electrode are on a same plane.    
     
     
         16 . The active matrix type liquid crystal display device according to  claim 10 , wherein 
 said common electrode and stud pixel electrode are made of a transparent conductive material.    
     
     
         17 . The active matrix type liquid crystal display device according to  claim 10 , wherein 
 said common electrode and said pixel electrode are on different planes respectively.    
     
     
         18 . The active matrix type liquid crystal display device according to  claim 10 , further comprising a plug which electrically connects said first conductive film and said common electrode with each other.  
     
     
         19 . The active matrix type liquid crystal display device according to  claim 10 , further comprising: 
 a common wiring which is provided an a plane different from that of said common electrode, and is electrically connected to said common electrode; and    a plug which is connected to said common wiring, and electrically connects said first conductive film and said common electrode with each other.    
     
     
         20 . The active matrix type liquid crystal display device according to  claim 19 , wherein 
 a second conductive film is provided between said first conductive film and said common wiring in order to enhance connection between said first conductive film and said common wiring.    
     
     
         21 . The active matrix type liquid crystal display device according to  claim 20 , wherein 
 said second conductive film is, made of a material same as that of said common electrode and/or said pixel electrode.    
     
     
         22 . The active matrix type liquid crystal display device according to  claim 10 , wherein 
 said first conductive film has a width equal to or wider than that of said slits.    
     
     
         23 . The active matrix type liquid crystal display device according to  claim 10 , wherein 
 said first conductive film functions as a black matrix.    
     
     
         24 . The active matrix type liquid crystal display device according to  claim 10 , further comprising a black matrix which is arranged on the other one of said pair of substrates in a predetermined pattern, and is covered by a flattening film, 
 wherein said first conductive film is provided on said flattening film.    
     
     
         25 . The active matrix type liquid crystal display device according to  claim 24 , wherein 
 said first conductive film has a pattern which is almost the same as that of said black matrix.    
     
     
         26 . The active matrix type liquid crystal display device according to  claim 10 , wherein 
 an electric field parallel to said pair of substrates is generated between said common electrode and said pixel electrode.    
     
     
         27 . A method of manufacturing an active matrix type liquid crystal display device, which is a method of manufacturing a liquid crystal display device comprising: a pair of substrates; a thin film transistor which is provided on one of said pair of substrates; data lines which are connected to a drain of said thin film transistor; a pixel electrode which is connected to a source of said thin film transistor; and a common electrode which generates an electric field between said pixel electrode, said method comprising 
 forming an insulation film on said data lines;    forming a first metal film on said insulation film; and    forming said common electrode by patterning said first metal film, with forming slits in portions of said common electrode that overlap said data lines.    
     
     
         28 . The method of manufacturing an active matrix type liquid crystal display device according to  claim 27 , further comprising 
 forming said pixel electrode in a shape having linear portions having a predetermined length,    wherein in said forming said common electrode, portions which oppose to said linear portions of said pixel electrode are formed, and said slits are formed to have a length which is almost the same as that of said linear portions.    
     
     
         29 . The method of manufacturing an active matrix type liquid crystal display device according to  claim 27 , wherein 
 in said forming said common electrode, said slits are formed in almost a center of a width of said overlapping portions.    
     
     
         30 . The method of manufacturing an active matrix type liquid crystal display device according to  claim 27 , wherein 
 in said forming said common electrode said overlapping portions of said common electrode are formed to have a width equal to or wider than that of said data lines.    
     
     
         31 . The method of manufacturing an active matrix type liquid crystal display device according to  claim 27 , wherein 
 in said forming said common electrode, said slits are formed to have a width smaller than that of said data lines.    
     
     
         32 . The method of manufacturing an active matrix type liquid crystal display device according to  claim 27 , wherein 
 said common electrode and said pixel electrode are formed in a substantially same step.    
     
     
         33 . A method of manufacturing an active matrix type liquid crystal display device, which is a method of manufacturing a liquid crystal display device comprising: a pair of substrates, a thin film transistor which is provided on one of said pair of substrates; data lines which are connected to a drain of said thin film transistor; a pixel electrode which is connected to a source of said thin film transistor, and a common electrode which generates an electric field between said pixel electrode, said method comprising: 
 forming an insulation film which covers said data lines;    forming a first metal film on said insulation film;    forming, said common electrode by patterning said first metal film, with forming slits in portions of said common electrode that overlap said data lines; and    forming a first conductive film on die other one of said pair of substrates, said first conductive film opposing to said data lines via said slits.    
     
     
         34 . The method of manufacturing an active matrix type liquid crystal display device according to  claim 33 , further comprising 
 forming said pixel electrode in a shape having linear portions having a predetermined length,    wherein in said forming said common electrode, portions which oppose to said linear portions of said pixel electrode are formed, and said slits are formed to have a length which is almost the materials film of said linear portions.    
     
     
         35 . The method of manufacturing an active matrix type liquid crystal display device according to  claim 33 , wherein 
 in said forming said common electrode, said slits are formed in almost a center of a width of said overlapping portions.    
     
     
         36 . The method of manufacturing at active matrix type liquid crystal display device according to  claim 33 , wherein 
 in said forming said common electrode, said overlapping portions of said common electrode are formed to have a width equal to or provider than that of said data lines.    
     
     
         37 . The method of manufacturing an active matrix type liquid crystal display device according to  claim 33 , wherein 
 in said forming said common electrode, said slits are formed to have a width smaller than that of said data lines.    
     
     
         38 . The method of manufacturing all active matrix type liquid crystal display device according to  claim 33 , wherein 
 said common electrode and said pixel electrode are formed in a substantially same step.    
     
     
         39 . The method of manufacturing an active matrix type liquid crystal display device according to  claim 33 , wherein: 
 said common electrode is connected to a common wiring which is provided on a plane different from a plane on which said common electrode is formed; and    said method further comprises forming a plug which electrically connects said common wiring and said first conductive film with each other.    
     
     
         40 . The method of manufacturing an active matrix type liquid crystal display device according to  claim 39 , further comprising 
 forming a second conductive film between said common wiring and said plug.    
     
     
         41 . The method of manufacturing an active matrix type liquid crystal display device according to claim  40 , wherein 
 said second conductive film is formed together with said common electrode and/or said pixel electrode in a same step.    
     
     
         42 . The method of manufacturing an active matrix type liquid crystal display device according to  claim 33 , further comprising: 
 forming a black matrix having a predetermined pattern on one surface of the other one of said pair of substrates; and    forming a flattening film on said black matrix,    wherein said first conductive film is formed on said flattening film.    
     
     
         43 . The method of manufacturing an active matrix type liquid crystal display device according to claim  42 , wherein 
 in said forming said first conductive film, said first conductive film is formed in a pattern same as that of said black matrix.