Liquid Crystal Device and Manufacturing Method Thereof

Abstract

The object can be achieved by the following structure. A material whose value of fracture toughness is greater than or equal to 1.5 [MPa·m 1/2 ] is used for a base substrate and a counter substrate which hold a liquid crystal material therebetween; a first sealant containing liquid crystal contaminants at less than or equal to 1×10 −4 wt % is provided so as be in contact with the liquid crystal material and to surround the liquid crystal material seamlessly; the second sealant is provided to surround the first sealant; and the base substrate and the counter substrate which hold the liquid crystal material therebetween using the first sealant and the second sealant are bonded with a bond strength of greater than or equal to 1 [N/mm 2 ].

What is claimed is: 
     
         1 . A liquid crystal device comprising:
 a liquid crystal material;   a first sealant being in contact with the liquid crystal material and surrounding the liquid crystal material seamlessly;   a second sealant surrounding the first sealant; and   a base substrate and a counter substrate whose value of fracture toughness is greater than or equal to 1.5 [MPa·m 1/2 ],   wherein the base substrate is bonded to the counter substrate with a bond strength of greater than or equal to 1 [N/mm 2 ] using the first sealant and the second sealant,   wherein the liquid crystal material is provided between the base substrate and the counter substrate while being in contact with the first sealant,   wherein the first sealant contains a liquid crystal contaminant at less than or equal to 1×10 wt %,   wherein the base substrate comprises:
 a first substrate; 
 a first electrode film provided over the first substrate; and 
 a first alignment film provided over the first electrode film and being in contact with the liquid crystal material, 
   wherein the counter substrate comprises:
 a second substrate; 
 a second electrode film provided over the second substrate; and 
 a second alignment film provided over the second electrode film and being in contact with the liquid crystal material, and 
   wherein a part of the first electrode film is electrically connected to a part of the second electrode film through a conductive material.   
     
     
         2 . The liquid crystal device according to  claim 1 , further comprising:
 an element layer provided over the first substrate,   wherein a part of the element layer is electrically connected to a part of the second electrode film through a conductive material.   
     
     
         3 . The liquid crystal device according to  claim 1 ,
 wherein the first sealant is a photo-curable material and   wherein the second sealant is a photo-curable material.   
     
     
         4 . The liquid crystal device according to  claim 1 ,
 wherein viscosity of the sealant before curing is less than or equal to 1000 cP, and   wherein a third sealant is provided so as to surround the second sealant seamlessly.   
     
     
         5 . A liquid crystal device comprising:
 a liquid crystal material exhibiting a blue phase;   a first sealant being in contact with the liquid crystal material and surrounding the liquid crystal material seamlessly;   a second sealant surrounding the first sealant; and   a base substrate and a counter substrate whose value of fracture toughness is greater than or equal to 1.5 [MPa·m 1/2 ],   wherein the base substrate is bonded to the counter substrate using the first sealant and the second sealant with a bond strength of greater than or equal to 1 [N/mm 2 ],   wherein the liquid crystal is provided between the base substrate and the counter substrate while being in contact with the first sealant,   wherein the first sealant contains a liquid crystal contaminant at less than or equal to 1×10 −4  wt %,   wherein the base substrate comprises:
 a first substrate; and 
 an element layer provided over the first substrate and being in contact with the liquid crystal material, and 
   wherein the counter substrate comprises:
 a second substrate; and 
 an electrode film provided over the second substrate and being in contact with the liquid crystal material, and 
   wherein a part of the element layer is electrically connected to a part of the electrode film through a conductive material.   
     
     
         6 . The liquid crystal device according to  claim 5 ,
 wherein the first sealant is a photo-curable material and   wherein the second sealant is a photo-curable material.   
     
     
         7 . The liquid crystal device according to  claim 5 ,
 wherein viscosity of the sealant before curing is less than or equal to 1000 cP, and   wherein a third sealant is provided so as to surround the second sealant seamlessly.   
     
     
         8 . A method for manufacturing a liquid crystal device, comprising:
 a step of:   forming an element layer over a top surface of a first substrate whose value of fracture toughness is greater than or equal to 1.5 [MPa·m 1/2 ];   providing a first temporary fixing substrate on a bottom surface of the first substrate with a slightly adhesive material provided therebetween;   forming a first alignment film on the element layer;   performing first alignment treatment on the first alignment film; and   forming a base substrate to which the first temporary fixing substrate is bonded, and   a step of:   forming an electrode film on a top surface of a second substrate whose value of fracture toughness is greater than or equal to 1.5 [MPa·m 1/2 ];   providing a second temporary fixing substrate on a bottom surface of the second substrate with a slightly adhesive material provided therebetween;   forming a second alignment film on the electrode film;   performing second alignment treatment on the second alignment film; and   forming a counter substrate to which the second temporary fixing substrate is bonded,   wherein the above steps are performed in no particular order, and   the method for manufacturing the liquid crystal device further comprising:   a step of:   providing, over the base substrate,
 a liquid crystal material; 
 a first sealant surrounding the liquid crystal material; 
 a second sealant surrounding the first sealant; and 
 a first conductive material over the element layer, 
   bonding a surface where the second alignment film in the counter substrate is formed to a surface where the first alignment film in the base substrate is formed under reduced pressure;   performing cure treatment on the first sealant, the second sealant, and the first conductive material;   bonding the base substrate and the counter substrate using the first sealant, and the second sealant;   connecting a part of the element layer and a part of the electrode film electrically using the first conductive material; and then   separating the slightly adhesive material and the first temporary fixing substrate from the base substrate, and   a step of:   separating the slightly adhesive material and the second temporary fixing substrate from the counter substrate,   wherein the above steps are performed in no particular order, and   wherein an external connection terminal is connected to a part of the element layer with a second conductive material interposed therebetween.   
     
     
         9 . A method for manufacturing a liquid crystal device comprising:
 a step of:   forming an element layer over a top surface of a first substrate whose value of fracture toughness is greater than or equal to 1.5 [MPa·m 1/2 ];   providing a first temporary fixing substrate on a bottom surface of the first substrate with a slightly adhesive material provided therebetween; and   forming a base substrate to which the first temporary fixing substrate is bonded, and   a step of:   forming an electrode film on a top surface of a second substrate whose value of fracture toughness is greater than or equal to 1.5 [MPa·m 1/2 ];   providing a second temporary fixing substrate on a bottom surface of the second substrate with a slightly adhesive material interposed therebetween; and   forming a counter substrate to which the second temporary fixing substrate is bonded,   wherein the above steps are performed in no particular order, and   the method for manufacturing the liquid crystal device further comprising:   a step of:   providing, over the base substrate,
 a liquid crystal material; 
 a first sealant surrounding the liquid crystal material; 
 a second sealant surrounding the first sealant; and 
 a first conductive material over the element layer, 
   bonding a surface where the electrode film in the counter substrate is formed to a surface where the element layer in the base substrate is formed under reduced pressure;   performing cure treatment on the first sealant, the second sealant, and the first conductive material;   bonding the base substrate and the counter substrate using the first sealant, and the second sealant;   connecting a part of the element layer and a part of the electrode film electrically using the first conductive material; and then   separating the slightly adhesive material and the first temporary fixing substrate from the base substrate, and   a step of:   separating the slightly adhesive material and the second temporary fixing substrate from the counter substrate,   wherein the above steps are performed in no particular order, and   wherein an external connection terminal is connected to part of the element layer through the second conductive material.   
     
     
         10 . A method for manufacturing a liquid crystal device comprising:
 a step of:   forming a first electrode film on a top surface of a first substrate whose value of fracture toughness is greater than or equal to 1.5 [MPa·m 1/2 ];   providing a first temporary fixing substrate over a bottom surface of the first substrate with a slightly adhesive material interposed therebetween;   forming a first alignment film over the first electrode film;   performing first alignment treatment on the first alignment film; and   forming a base substrate to which the first temporary fixing substrate is bonded, and   a step of:   forming a second electrode film on a top surface of a second substrate whose value of fracture toughness is greater than or equal to 1.5 [MPa·m 1/2 ];   providing a second temporary fixing substrate over a bottom surface of the second substrate with a slightly adhesive material interposed therebetween;   forming a second alignment film over the second electrode film;   performing second alignment treatment on the second alignment film; and   forming a counter substrate to which the second temporary fixing substrate is bonded,   wherein the above steps are performed in no particular order, and   the method for manufacturing a liquid crystal device further comprising:   a step of:   providing, over the base substrate,
 a liquid crystal material; 
 a first sealant surrounding the liquid crystal material; 
 a second sealant surrounding the first sealant; and 
 a first conductive material over the element layer, 
   bonding a surface where the second alignment film in the counter substrate is formed to a surface where the first alignment film in the base substrate is formed under reduced pressure;   performing cure treatment on the first sealant, the second sealant, and the first conductive material;   bonding the base substrate and the counter substrate using the first sealant, and the second sealant;   connecting a part of the first electrode film and a part of the second electrode film electrically using the first conductive material; and then   separating the slightly adhesive material and the first temporary fixing substrate from the base substrate, and   a step of:   separating the slightly adhesive material and the second temporary fixing substrate from the counter substrate,   wherein the above steps are performed in no particular order, and   wherein an external connection terminal is connected to a part of the first electrode film or the second electrode film through the second conductive material.