JP4848701B2 - Manufacturing method of liquid crystal device - Google Patents

Description

The present invention relates to a method for manufacturing a liquid crystal device.

  A liquid crystal device is mounted as a light valve (light modulation means) of a projection display device such as a projector. With the increase in projector brightness, it is important to ensure the light resistance of the liquid crystal device. Conventionally, polyimide was mainly used as the material for the alignment film of the liquid crystal device. However, in recent years, metal oxides such as SiOx orthorhombic films (x = 1 to 2) have been used as the material for the alignment film in order to improve light resistance. Things are also being developed.

In the alignment film made of a metal oxide, a hydroxyl group (for example, silanol group: —Si—OH) is formed on the surface in an atmosphere containing moisture. Since the hydroxyl group has high hydration properties (affinity with moisture), moisture tends to adhere to the surface of the alignment film. When moisture adheres to the surface of the alignment film, the alignment changes, causing alignment failure. On the other hand, in order to prevent moisture from adhering, a method of modifying the surface by treating the surface of the metal oxide with a higher alcohol having a long straight chain has been disclosed (for example, see Patent Document 1). .
JP-A-11-160711

However, since alcohol is a long-chain organic compound, it cannot be said that it has sufficient resistance to strong heat and strong light. In particular, in a harsh environment exposed to heat and light from the light source of the projector, the long straight chain of alcohol may deteriorate, and the alignment film itself may deteriorate. When the alignment film is deteriorated, the light modulation function of the liquid crystal device is lowered, and the brightness and contrast of the projector are lowered. In addition, the presence of moisture may cause deterioration due to a hydrolysis reaction.
In view of the circumstances as described above, an object of the present invention is to provide a method for manufacturing a liquid crystal device having high light resistance and capable of suppressing deterioration of an alignment film.

  In order to achieve the above object, a liquid crystal device according to the present invention is a liquid crystal device in which a pair of opposed substrates sandwich a liquid crystal, and a metal oxide is disposed on the liquid crystal side of at least one of the pair of substrates. And an atom or atomic group having a lower hydration property than the hydroxyl group is bonded to at least a part of the metal atoms on the surface of the alignment film without an oxygen atom. It is characterized by becoming.

  According to the present invention, since the alignment film is formed of the metal oxide film, it has high light resistance. In addition, an atom or atomic group having a lower hydration property than the hydroxyl group is bonded to at least a part of the metal atoms on the surface of the metal oxide film without passing through a highly hydratable oxygen atom. The formation of hydroxyl groups on the surface of the membrane can be prevented. As a result, the hydration property of the surface of the alignment film is lowered, and it becomes difficult for moisture to adhere to the surface, so that deterioration of the alignment film can be suppressed.

Moreover, it is preferable that the atom or atomic group is directly bonded to at least a part of metal atoms on the surface of the metal oxide.
In the present invention, since it is directly bonded to at least a part of the metal atoms on the surface of the metal oxide, it is possible to more reliably prevent the formation of hydroxyl groups on the surface of the metal oxide film.

The atom is at least one of a boron atom, a nitrogen atom, a carbon atom, and a fluorine atom, and the atomic group is -BFx, -BHx, -NFx, -NHx, -CFx, -CHx, and -BHxFy. , -NHxFy, -CHxFy, -CN are preferred.
Boron atom (hereinafter referred to as “B atom”), nitrogen atom (hereinafter referred to as “N atom”), carbon atom (hereinafter referred to as “C atom”) and fluorine atom (hereinafter referred to as “F atom”). ) And -BFx, -BHx, -NFx, -NHx, -CFx, -CHx and -BHxFy, -NHxFy, -CHxFy, -CN groups are hydrated compared to hydroxyl groups when bonded to metal atoms. The nature is low. By bonding such atoms or atomic groups to the surface of the metal oxide film, it is possible to make it difficult for moisture to adhere to the surface of the alignment film.
In particular, when the atomic group CFx is bonded to the metal oxide film, a strong C—F bond exists on the outermost surface, so that the metal oxide film can be prevented from being directly irradiated with light, and the light resistance of the alignment film can be reduced. There is also an advantage that it can be increased. Note that x is an integer of 0 to 3, and y is an integer satisfying x + y = (valence of atom directly bonded to metal atom-1).

  A manufacturing method of a liquid crystal device according to another aspect of the present invention is a manufacturing method of a liquid crystal device in which a pair of opposed substrates sandwich a liquid crystal, and a film that forms a metal oxide film on the surfaces of the pair of substrates And a surface treatment step of bonding an atom or atomic group having a lower hydration property than the hydroxyl group to at least a part of the metal atoms on the surface of the metal oxide film so as not to intervene oxygen atoms. It is characterized by doing.

  According to the present invention, at least a part of the metal atoms on the surface of the metal oxide is bonded with an atom or atomic group having a lower hydration property than the hydroxyl group so as not to intervene an oxygen atom. It is possible to manufacture a liquid crystal device that can prevent the formation of hydroxyl groups on the surface of the film and that makes it difficult for moisture to adhere to the surface of the alignment film.

In the film formation step, the metal oxide film is formed by any one of physical vapor deposition, chemical vapor deposition, and sol-gel method, and in the surface treatment step, the metal oxide film is formed on the metal oxide film. It is preferable to irradiate the liquid crystal side surface with the plasma of the atoms or atomic groups.
Examples of the physical vapor deposition method (PVD method) include vapor deposition and sputtering. Examples of the chemical vapor deposition method (CVD method) include thermal CVD and plasma CVD.

  As a method for manufacturing a substrate of a liquid crystal device, so-called multi-chamfering, in which a plurality of panel substrates are manufactured from a single large mother substrate, is widely performed. It is formed on the entire surface. In the present invention, since the plasma irradiation range (the film forming range) is wide in plasma irradiation, even on the liquid crystal side surface of the metal oxide film formed on the large mother substrate, atoms or atoms You can join groups.

In the film formation step, the metal oxide film is formed by any one of physical vapor deposition, chemical vapor deposition, and sol-gel method, and in the surface treatment step, the metal oxide film is formed on the metal oxide film. It is preferable to irradiate the surface of the liquid crystal with a beam of the atoms or atomic groups.
In the present invention, by irradiating a beam, atoms or atomic groups can be bonded to the liquid crystal side surface of the metal oxide film at an accurate position. Thereby, an alignment film with good film quality can be obtained.

In the film formation step, the metal oxide film is formed by any one of physical vapor deposition, chemical vapor deposition, and sol-gel method, and in the surface treatment step, the metal oxide film is formed on the metal oxide film. It is preferable to wet-treat the liquid crystal side surface with hydrofluoric acid or buffered hydrofluoric acid.
According to the present invention, F atoms can be bonded to the liquid crystal side surface of the metal oxide film. When plasma irradiation or beam irradiation is performed, the substrate may be exposed to a high temperature in a vacuum, which requires a vacuum process or a process for cooling the substrate that has reached a high temperature. On the other hand, when the metal oxide film is wet-treated as in the present invention, the surface of the metal oxide film can be treated at normal temperature or at a temperature close to normal temperature under normal pressure. Thereby, it is not necessary to provide a separate vacuum process or a process of cooling the substrate, and the manufacturing efficiency can be increased.

In the film formation step, the metal oxide film is formed by any one of physical vapor deposition, chemical vapor deposition, and sol-gel method, and in the surface treatment step, the metal oxide film is formed on the metal oxide film. It is preferable to subject the liquid crystal side surface to gas phase treatment with hydrogen fluoride.
According to the present invention, F atoms can be bonded to the liquid crystal side surface of the metal oxide film. When performing wet processing, it is necessary to separately provide a step of drying the substrate. On the other hand, as in the present invention, by performing a gas phase treatment with hydrogen fluoride which is a gas, metal oxidation is performed while the substrate is dried. Since the surface of the film can be treated, it is not necessary to provide a drying step. Thereby, manufacturing efficiency can further be improved.

In the film formation step, the metal oxide film is formed by any one of physical vapor deposition, chemical vapor deposition, and sol-gel method, and in the surface treatment step, the metal oxide film is formed on the metal oxide film. It is preferable to perform a carbon electrode arc discharge treatment on the liquid crystal side surface.
According to the present invention, C atoms can be bonded to the liquid crystal side surface of the metal oxide film. Since C atoms can be sputtered by the carbon electrode arc discharge, C atoms can be bonded even in a wide surface range such as a metal oxide film formed on a large mother substrate.

In the film forming step, the step of forming the metal oxide film by physical vapor deposition or chemical vapor deposition, and the step of plasma irradiation or beam irradiation of the atoms or atomic groups, It is preferable to carry out continuously in a vacuum.
Thereby, it can prevent that another atom and atomic group couple | bond with the surface of a metal oxide film. That is, it becomes difficult to form hydroxyl groups on the surface of the alignment film.
In the film formation step, it is preferable that the step of forming the metal oxide film by a physical vapor deposition method or a chemical vapor deposition method and the carbon electrode arc discharge treatment step are continuously performed in a vacuum.
This prevents other atoms and atomic groups from binding to the surface of the metal oxide film, so that silanol groups are less likely to be formed on the surface of the alignment film.

A projection display device according to another aspect of the present invention includes the above-described liquid crystal device.
According to the present invention, since a liquid crystal device capable of suppressing a decrease in light resistance is mounted, a projection display device having an excellent light modulation function and a high contrast can be obtained.

[First embodiment]
A liquid crystal device according to a first embodiment of the present invention will be described with reference to the drawings. In the present embodiment, an active matrix type liquid crystal device using a thin film transistor (hereinafter referred to as TFT) element as a switching element is used as a light valve of a projection display device such as a projector. I will give you a description.

(Liquid crystal device)
FIG. 1 is a plan view showing the overall configuration of the liquid crystal device 1. The liquid crystal device 1 has a configuration in which a TFT array substrate 4 and a counter substrate 5 are bonded together by a sealing material 7, and a liquid crystal 6 is sealed in a region partitioned by the sealing material 7. A light-shielding film (peripheral parting) 8 made of a light-shielding material is formed in a region inside the sealing material 7. An area inside the peripheral parting 8 is a display area 9 for displaying an image, a moving image, or the like. In the display area 9, a plurality of dot areas 10 are provided in a matrix.

  The peripheral portion of the TFT array substrate 4 is an overhanging region that protrudes from the counter substrate 5. A scanning line driving circuit 11 for generating a scanning signal is formed on the left side and the right side in the drawing in the overhang region. On the upper side in the figure, a wiring 13 that connects the left and right scanning line driving circuits 11 is routed. On the lower side in the figure, a data line driving circuit 12 for generating a data signal and a connection terminal 14 for connecting to an external circuit or the like are formed. In a region between the scanning line driving circuit 9 and the connection terminal 14, a wiring 15 for connecting the two is formed. At each corner of the counter substrate 5, an inter-substrate conductive material 17 is provided for electrical connection between the TFT array substrate 4 and the counter substrate 5.

FIG. 2 is a diagram illustrating a configuration along the AA cross section of FIG. 1.
The TFT array substrate 4 is formed, for example, on a base material 4a formed from a material having high translucency such as glass or quartz, a pixel electrode 18 formed on the liquid crystal side of the base material 4a, and the pixel electrode 18. The alignment film 16 is used as a main component. The pixel electrode 18 is formed of a transparent conductive material such as ITO (Indium Tin Oxide). In addition, a TFT element (not shown) is connected to the pixel electrode 18, and a scanning line and a data line (not shown) are connected to the TFT element.

  The counter substrate 5 is formed on a base material 5a made of a light-transmitting material such as glass or quartz, the common electrode 28 formed on the liquid crystal side of the base material 5a, and the common electrode 28, like the TFT array substrate 4. The alignment film 26 is mainly used. Similar to the pixel electrode 18, the common electrode 28 is formed of a transparent conductive material such as ITO. The liquid crystal 6 is provided in contact with the alignment film 16 and the alignment film 26. Polarizing plates 19 and 29 are provided outside the TFT array substrate 4 and the counter substrate 5 (on the side opposite to the liquid crystal).

FIG. 3 is a cross-sectional view showing the configuration of the alignment film 16. Hereinafter, although the alignment film 16 of the TFT array substrate 4 will be described, the alignment film 26 of the counter substrate 5 has the same configuration. The upper side in the figure is the liquid crystal 6 side surface, and the lower side in the figure is the TFT array substrate 4 side.
The alignment film 16 is mainly composed of the metal oxide film 31 and has a thickness of about 0.02 to 0.3 μm (preferably 0.02 to 0.08 μm). In the present embodiment, SiO ₂ is used as the metal oxide constituting the metal oxide film 31.

The metal oxide film 31 is formed so that a SiO ₂ crystal grows in a column shape from the TFT array substrate 4 side to the liquid crystal 6 side surface, and the columnar structure is inclined obliquely with respect to the normal direction of the substrate surface, for example. Has been. The Si atoms 33 on the surface side of the metal oxide film 31 are directly bonded to N atoms 32 as shown in FIG. That is, Si—N bonds are formed on the surface of the metal oxide film 31.

(Manufacturing method of liquid crystal device)
Next, a method for manufacturing the liquid crystal device 1 configured as described above will be described focusing on the manufacturing process of the alignment film 16 in particular. In the present embodiment, a method in which a plurality of liquid crystal devices are collectively formed using a mother substrate having a large area and separated into individual liquid crystal devices 1 by cutting will be described as an example.
First, a process of forming a TFT array-side mother substrate that becomes the TFT array substrate 4 will be briefly described. Pixel electrodes 18, TFT elements, other wirings, and the like are formed in each display region 9 of a large base material 34 (see FIG. 4) made of a light-transmitting material such as glass or plastic.

Next, the alignment film 16 is formed so as to cover the pixel electrodes 18, TFT elements, and other wirings formed on the substrate 34. FIG. 4 is a diagram illustrating a process of forming the alignment film 16.
The step of forming the alignment film 16 includes a film forming step for forming the metal oxide film 31 and a surface treatment step for bonding N atoms to Si atoms on the surface of the metal oxide film 31.
In the film forming step, as shown in FIG. 4A, a metal oxide film 31 is formed by obliquely depositing SiO ₂ on the surface of the base material 34 on which electrodes, wirings and the like are formed, for example, under vacuum. . The metal oxide film 31 is manufactured by physical vapor deposition such as vapor deposition or sputtering. Si atoms 33 are arranged on the surface of the metal oxide film 31.

In the surface treatment step, as shown in FIG. 4B, the surface of the metal oxide film 31 is irradiated with N ₂ plasma 35, for example, under vacuum. N atoms are directly bonded to Si atoms 33 on the surface of the metal oxide film 31 without intervening oxygen atoms. Such termination treatment by plasma irradiation is continuously performed in a vacuum without opening to the atmosphere between the film formation step and the surface treatment step.

In the film formation step, the metal oxide film 31 may be formed by a chemical vapor deposition method or a sol-gel method in addition to the physical vapor deposition method. Further, in the surface treatment process, for example, after the film formation process, the atmosphere is once opened to the atmosphere, and then the surface of the metal oxide film 31 is irradiated with N ₂ plasma to bond to the surface of the metal oxide film 31 when the atmosphere is released. A method of replacing other atoms with N atoms may also be used (substitution process). This substitution treatment is performed by using the metal oxide film 31 as in the case where the metal oxide film 31 is formed by a chemical vapor deposition method, a sol-gel method, or the like in addition to a physical vapor deposition method that opens to the atmosphere before the surface treatment process. This is performed in order to replace N atoms with other atoms on the surface when other atoms are bonded to the surface.

  For example, after the metal oxide film 31 is formed by the physical vapor deposition method, the chemical vapor deposition method, the sol-gel method, or the like, the metal oxide film 31 is irradiated with an ion beam of nitrogen ions (N ions). Alternatively, a technique of forming a Si—N bond on the surface of the metal oxide film 31 may be used. In this case, neutralization is performed after accelerating N ions and irradiation is performed while neutralizing the ions, thereby preventing charge-up of the surface of the metal oxide film 31 and forming Si-N bonds efficiently. . Moreover, if the directivity of the beam is relaxed, it is possible to perform processing over a wide area in the form of a shower. Furthermore, if the beam is incident from an oblique direction, the alignment direction can be controlled.

  For example, rubbing treatment is performed on the metal oxide film 31 in which N atoms are bonded to the Si atoms 33 on the surface by any one of the above methods, thereby completing the alignment film 16. After the alignment film 16 is formed, the sealing material 7 is formed on the peripheral portion of each display region 9, and the liquid crystal is applied to the display region 9 surrounded by the sealing material 7.

  Next, a process for forming a counter-side mother substrate to be the counter substrate 5 will be briefly described. As in the case of the TFT array-side mother substrate, wirings, electrodes, and the like are formed in each display region 9 of a large base material made of a light-transmitting material such as glass or plastic. Next, an alignment film 26 made of a metal oxide film is formed in each display region 9. The alignment film 26 is formed by the same method as the formation of the alignment film 16 described above.

  Next, the TFT array side mother substrate and the opposite side mother substrate are bonded together. Both substrates are brought close to each other so that the TFT array side mother substrate is adhered to the sealing material on the opposite side mother substrate. Thereafter, a scribe line is formed on the counter substrate 5 and the TFT array substrate 4, the liquid crystal panel is cut along the scribe line, each liquid crystal panel is washed, and polarizing plates 19 and 29 are provided on the outer surface of each liquid crystal panel. Adhere. Thereafter, a drive driver is mounted on each liquid crystal panel, and the liquid crystal device 1 is completed.

  Thus, according to this embodiment, since the alignment film 16 is formed by the metal oxide film 31, it has high light resistance. In addition, since N atoms 32 having a lower hydration property than the hydroxyl group are bonded to at least a part of the Si atoms 33 on the surface of the metal oxide film 31 so as not to intervene oxygen atoms, It is possible to prevent the formation of hydroxyl groups on the surface. Thereby, the hydration property of the surface of the alignment film 16 is lowered, and moisture hardly adheres to the surface, so that the deterioration of the alignment film 16 can be suppressed.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. Similar to the first embodiment, in the following drawings, the scale is appropriately changed to make each member a recognizable size. Moreover, about the component same as 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted. Note that the overall configuration of the liquid crystal device 201 according to the present embodiment and the flow of the entire manufacturing process of the liquid crystal device 201 are substantially the same as those of the liquid crystal device 1 according to the first embodiment, and thus description thereof is omitted. In the present embodiment, since the configuration of the alignment film and the method for manufacturing the alignment film are different from those in the first embodiment, this point will be mainly described.

(Configuration of alignment film)
FIG. 5 is a diagram showing the configuration of the alignment film 216 provided on the TFT array substrate 4 side of the liquid crystal device 201. Similar to the first embodiment, the alignment film 216 on the TFT array substrate 4 side will be described, but the alignment film on the counter substrate 5 has the same configuration.

The alignment film 216 is mainly composed of the metal oxide film 31 and has a thickness of about 0.02 to 0.3 μm (preferably 0.02 to 0.08 μm). Also in this embodiment, SiO ₂ is used as the metal oxide constituting the metal oxide film 31 as in the first embodiment. Of course, other types of metal oxides such as Al ₂ O ₃ may be used.

The metal oxide film 31 is formed so that the SiO ₂ crystal from the TFT array substrate 4 side to the surface side is inclined, for example, obliquely with respect to the normal direction of the substrate surface. The Si atoms 33 are directly bonded to the F atoms 232 as shown in FIG. That is, Si—F bonds are formed on the surface of the metal oxide film 31.

(Method for producing alignment film)
Next, a method for manufacturing the alignment film 216 in the liquid crystal device 201 configured as described above will be described.
The step of forming the alignment film 216 includes a film forming step of forming the metal oxide film 31 and a surface treatment step of bonding F atoms to Si atoms on the surface of the metal oxide film 31 as in the first embodiment. ing.

In the film forming step, the metal oxide film 31 is formed by obliquely depositing SiO ₂ on the surface of the base material 34 on which the electrodes, wirings, and the like are formed, for example, in the same manner as in the first embodiment. The specific method of forming the metal oxide film 31 is also performed by physical vapor deposition such as vapor deposition or sputtering as in the first embodiment.

In the surface treatment step, the metal oxide film 31 is irradiated with CF ₄ plasma, for example, under vacuum. F atoms are directly bonded to Si atoms 33 on the surface of the metal oxide film 31 without intervening oxygen atoms. This termination treatment is performed continuously in a vacuum without opening to the atmosphere between the film formation step and the surface treatment step, as in the first embodiment.

As in the first embodiment, in the film formation step, the metal oxide film 31 may be manufactured by a chemical vapor deposition method or a sol-gel method in addition to the physical vapor deposition method.
As for the surface treatment process, it is possible to select an optimum method from the termination treatment, replacement treatment, ion beam irradiation, and the like.

  Further, in the surface treatment process, in addition to these techniques, the surface of the metal oxide film 31 is wet-treated using hydrofluoric acid or buffered hydrofluoric acid, so that the surface of the metal oxide film 31 is bonded to Si—F. Can also be formed. The buffered hydrofluoric acid is an aqueous solution in which a hydrofluoric acid-based substance is mixed, for example, hydrofluoric acid and ammonium hydrofluoric acid. In addition to the aqueous solution obtained by mixing the hydrofluoric acid and ammonium fluoride mentioned in the example, a hydrofluoric acid-based substance can be appropriately combined.

Furthermore, in the surface treatment step, a gas-phase treatment is performed on the surface of the metal oxide film 31 using hydrogen fluoride (HF) which is a gas, thereby forming a Si—F bond on the surface of the metal oxide film 31. There may be.
For example, rubbing treatment is performed on the metal oxide film 31 in which F atoms are bonded to the Si atoms 33 on the surface by any one of the above methods, thereby completing the alignment film 216.

  As described above, according to the present embodiment, the F atoms 232 are directly bonded to the Si atoms 33 on the surface of the metal oxide film 31, thereby preventing the formation of hydroxyl groups on the surface of the metal oxide film 31. Can do. Thereby, the hydration property of the surface of the alignment film 216 is lowered, and moisture hardly adheres to the surface, so that a decrease in light resistance can be suppressed.

  When F atoms are bonded to Si atoms 33 on the surface of the metal oxide film 31, when plasma irradiation or beam irradiation is performed, the substrate may be exposed to a high temperature in a vacuum. A process of cooling the substrate that has become necessary becomes necessary. On the other hand, when the metal oxide film 31 is wet-treated, the surface of the metal oxide film 31 can be treated at normal temperature or at a temperature close to normal temperature under normal pressure. Thereby, it is not necessary to provide a vacuum process or a process for cooling the base material 34 separately, and the manufacturing efficiency can be increased.

  In addition, when performing wet treatment when bonding F atoms, it is necessary to separately provide a step of drying the base material 34, whereas when performing vapor phase treatment with hydrogen fluoride, which is a gas, the base material 34 Since the surface of the metal oxide film 31 can be treated while being dried, it is not necessary to provide a drying step. Thereby, manufacturing efficiency can further be improved.

[Third embodiment]
Next, a third embodiment of the present invention will be described. Similar to the first embodiment, in the following drawings, the scale is appropriately changed to make each member a recognizable size. Moreover, about the component same as 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted. In the present embodiment, the configuration of the alignment film and the method for manufacturing the alignment film different from those in the first embodiment will be mainly described.

(Configuration of alignment film)
FIG. 6 is a diagram showing the configuration of the alignment film 316 provided on the TFT array substrate 4 side of the liquid crystal device 301. Similar to the first embodiment, the alignment film 316 on the TFT array substrate 4 side will be described, but the alignment film on the counter substrate 5 has the same configuration.

The alignment film 316 is mainly composed of the metal oxide film 31 and has a thickness of about 0.02 to 0.3 μm (preferably 0.02 to 0.08 μm). Also in this embodiment, SiO ₂ is used as the metal oxide constituting the metal oxide film 31 as in the first embodiment.

The metal oxide film 31 is formed so that the SiO ₂ crystal from the TFT array substrate 4 side to the surface side is inclined, for example, obliquely with respect to the normal direction of the substrate surface. The Si atom 33 is directly bonded to the C atom 332 as shown in FIG. That is, Si—C bonds are formed on the surface of the metal oxide film 31.

(Method for producing alignment film)
Next, a method for manufacturing the alignment film 316 in the liquid crystal device 301 configured as described above will be described.
The step of forming the alignment film 316 includes a film forming step of forming the metal oxide film 31 and a surface treatment step of bonding C atoms to Si atoms on the surface of the metal oxide film 31 as in the first embodiment. ing.
In the film forming step, the metal oxide film 31 is formed by obliquely depositing SiO ₂ on the surface of the base material 34 on which the electrodes, wirings, and the like are formed, for example, in the same manner as in the first embodiment. The metal oxide film 31 is manufactured by physical vapor deposition such as vapor deposition or sputtering. In addition to the physical vapor deposition method, the metal oxide film 31 may be manufactured by a chemical vapor deposition method or a sol-gel method as in the first embodiment.

In the surface treatment step, for example, termination treatment is performed by irradiating the metal oxide film 31 with CF ₄ plasma under vacuum, and C atoms are directly bonded to the Si atoms 33 on the surface of the metal oxide film 31. In addition to termination processing, it is possible to select and perform an optimal method from among replacement processing, ion beam irradiation, and the like. In the surface treatment step, in addition to these methods, it is also possible to perform a termination treatment and a substitution treatment by performing a carbon electrode arc discharge treatment in a vacuum.
For example, rubbing treatment is performed on the metal oxide film 31 in which C atoms are bonded to the Si atoms 33 on the surface by any one of the above methods, thereby completing the alignment film 316.

  Thus, according to the present embodiment, it is possible to prevent the formation of hydroxyl groups on the surface of the metal oxide film 31 by directly bonding C atoms to the Si atoms 33 on the surface of the metal oxide film 31. it can. Thereby, the hydration property of the surface of the alignment film 316 decreases, and moisture hardly adheres to the surface, so that a decrease in light resistance can be suppressed.

  Further, as in the present embodiment, since the termination treatment and the substitution treatment are performed by arc discharge of the carbon electrode in vacuum, C atoms can be converted into plasma by the carbon electrode arc discharge. Thereby, even if it is the wide range of the surface of the metal oxide film 31 formed in the large mother substrate, C atoms can be sputtered and combined.

[Fourth embodiment]
Next, a fourth embodiment of the present invention will be described. Similar to the first embodiment, in the following drawings, the scale is appropriately changed to make each member a recognizable size. Moreover, about the component same as 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted. In the present embodiment, the configuration of the alignment film will be mainly described.

(Configuration of alignment film)
FIG. 7 is a diagram showing the configuration of the alignment film 416 provided on the TFT array substrate 4 side of the liquid crystal device 401. Similar to the first embodiment, the alignment film 416 on the TFT array substrate 4 side will be described, but the alignment film on the counter substrate 5 has the same configuration.

The alignment film 416 is mainly composed of a metal oxide film 431 and has a thickness of about 0.02 to 0.3 μm (preferably 0.02 to 0.08 μm). Al ₂ O ₃ is used as a metal oxide constituting the metal oxide film 431. The metal oxide film 431 is formed such that crystals from the TFT array substrate 4 side to the surface side are inclined obliquely with respect to the normal direction of the substrate surface, for example. As shown in FIGS. 7A to 7C, the Al atoms 433 on the surface side of the metal oxide film 431 are N atoms 32 (FIG. 7A) and F atoms 232 (FIG. 7B). And C atoms 332 (FIG. 7C) are directly bonded to each other.

Thus, even when the metal oxide film 431 is made of Al ₂ O ₃ , the same effects as those in the above embodiments can be obtained. That is, by directly bonding N atoms 32, F atoms 232, and C atoms 332 to Al atoms 433 on the surface, it is possible to prevent the formation of hydroxyl groups on the surface of the metal oxide film 431. Since the hydration property of the surface of the alignment film 416 decreases and moisture hardly adheres to the surface, a decrease in light resistance can be suppressed.

[Projection display]
Next, an embodiment of a projection display device using the liquid crystal device of each embodiment as a light modulation device will be described.
FIG. 8 is a diagram schematically showing an internal configuration of a projector 101 as an example of a projection display device.
The projector 101 is a three-plate color liquid crystal projector provided with a transmissive liquid crystal light valve for each of different colors of R (red), G (green), and B (blue), for example, and includes a light source 107, a fly-eye lens 108, 109, dichroic mirrors 110 and 111, reflection mirrors 112, 113, and 114, liquid crystal light valves 115, 116, and 117, a cross dichroic prism 118, and a projection lens 119. The projector 101 may be a single plate type.

  The light source 107 includes, for example, a lamp 107a such as a high-pressure mercury lamp that emits white light, and a reflector 107b that reflects light from the lamp 107a. The fly-eye lenses 108 and 109 make the illuminance distribution of light from the light source 107 uniform. The fly-eye lens 108 on the light source 107 side forms a plurality of secondary light source images. The fly eye lens 109 on the screen 103 side superimposes the secondary light source image formed by the fly eye lens 108. Of the white light emitted from the light source 107, the dichroic mirror 110 transmits the red light LR and reflects the green light LG and the blue light LB. The dichroic mirror 111 reflects the green light LG and transmits the blue light LB.

The liquid crystal light valves 115, 116, and 117 modulate the emitted red light, green light, and blue light, respectively, based on a predetermined image signal. The cross dichroic prism 118 is formed by bonding four right-angle prisms. On the inner surface, a dielectric multilayer film 118a that reflects red light and a dielectric multilayer film 118b that reflects blue light are formed in a cross shape. Three color lights are synthesized by the dielectric multilayer films 118a and 118b, and light (image light) representing a color image is formed. The projection lens 119 projects image light toward the screen 103.
As the liquid crystal light valves 115, 116, 117, the above-described liquid crystal devices 1, 201, 301, 401 are used here. When used as the liquid crystal light valves 115, 116, 117, the size of the liquid crystal devices 1, 201, 301, 401 is about 4.6 square centimeters (about 0.7 square inches). Light from the light source 107 is converted into parallel light (linearly polarized light), modulated by the liquid crystal device 1, and each modulated color light is projected on the screen 103 by the projection lens 119.

  According to this embodiment, since the liquid crystal devices 1, 201, 301, and 401 having high light resistance and capable of suppressing the deterioration of the alignment films 16 and 26 are mounted, the light modulation is excellent. A projector 101 with high contrast can be obtained.

The technical scope of the present invention is not limited to the above-described embodiment, and appropriate modifications can be made without departing from the spirit of the present invention.
For example, to bind to the Si atom 33 of the surface of the metal oxide film 31 is not limited to atomic _{-BFx, -BHx, -NFx, -NHx,} -CFx (CF, CF 2, CF 3), - CHx (CH _{, CH 2, CH 3),} - BHxFy, -NHxFy, or an atomic group such as -CHxFy (e.g. CHF _3, etc.). When, for example, CFx is bonded to the Si atoms 33 on the surface of the metal oxide film 31, it is preferable to irradiate CF ₄ plasma. Further, when C ₂ H ₂ (ethylene), H ₂ and CHF ₃ are mixed, and these are converted into plasma and irradiated, CFx or CHx can be combined. As an example, FIG. 9 shows a state in which the CF ₃ atomic group 36 is bonded.

  Since these atomic groups are less hydratable than hydroxyl groups, even when they are bonded to the surface of the metal oxide film 31 so as not to intervene oxygen atoms, hydroxyl groups are formed on the surface of the metal oxide film 31. Can be prevented. In particular, CFx has a strong C—F bond on the outermost surface, so that it is possible to prevent the metal oxide film 31 from being directly irradiated with light and to improve the light resistance of the alignment film 16. There is.

In each of the above embodiments, the alignment films 16, 216, 316, and 416 in which one type of atom or atomic group is bonded to the metal oxide films 31 and 431 have been described as examples. However, the present invention is not limited thereto. There may be a plurality of types of atoms or atomic groups bonded to the metal oxide films 31 and 431. As an example, FIG. 10 shows a state in which N atoms 32, CF ₂ atomic groups 37, and NH atomic groups 38 are bonded to Si atoms 33 on the surface of the metal oxide film 31, respectively.

1 is a diagram illustrating an overall configuration of a liquid crystal device according to a first embodiment of the present invention. It is sectional drawing of the liquid crystal device which concerns on this embodiment. It is a figure which shows the structure of the alignment film of the liquid crystal device which concerns on this embodiment. It is process drawing which manufactures the liquid crystal device which concerns on this embodiment. It is a figure which shows the structure of the orientation film of the liquid crystal device which concerns on 2nd Embodiment of this invention. It is a figure which shows the structure of the orientation film of the liquid crystal device which concerns on 3rd Embodiment of this invention. It is a figure which shows the structure of the orientation film of the liquid crystal device which concerns on 4th Embodiment of this invention. It is a figure which shows the structure of the projection type display apparatus which concerns on this invention. It is a figure which shows the structure of another alignment film of the liquid crystal device which concerns on this invention. It is a figure which shows the structure of another alignment film of the liquid crystal device which concerns on this invention.

Explanation of symbols

1, 201, 301, 401 ... Liquid crystal device 4 ... TFT array substrate 16 ... Alignment film 16, 26, 216, 316, 416 ... Alignment film 31, 431 ... Metal oxide film 32 ... N atom 232 ... F atom 332 ... C atom 101 ... Projector

Claims (8)

A method of manufacturing a liquid crystal device in which a pair of opposing substrates sandwich a liquid crystal,
A film forming step of forming a metal oxide film on the surfaces of the pair of substrates;
A surface treatment step of bonding a predetermined atom or a predetermined atomic group to at least a part of the metal atoms on the surface of the metal oxide film without interposing oxygen atoms,
The predetermined atom is at least one of a boron atom, a nitrogen atom, a carbon atom and a fluorine atom,
The predetermined atomic group is at least one of -BFx, -BHx, -NFx, -NHx, -CFx, -CHx, and -BHxFy, -NHxFy, -CHxFy, -CN. Device manufacturing method. In the film formation step, the metal oxide film is formed by any one of physical vapor deposition, chemical vapor deposition, and sol-gel method,
2. The method of manufacturing a liquid crystal device according to claim 1, wherein, in the surface treatment step, plasma of the atoms or atomic groups is irradiated on the liquid crystal side surface of the metal oxide film. In the film formation step, the metal oxide film is formed by any one of physical vapor deposition, chemical vapor deposition, and sol-gel method,
2. The method of manufacturing a liquid crystal device according to claim 1, wherein, in the surface treatment step, the surface of the metal oxide film on the liquid crystal side is irradiated with a beam of the atoms or atomic groups. In the film formation step, the metal oxide film is formed by any one of physical vapor deposition, chemical vapor deposition, and sol-gel method,
2. The method of manufacturing a liquid crystal device according to claim 1, wherein in the surface treatment step, the liquid crystal side surface of the metal oxide film is wet-treated with hydrofluoric acid or buffered hydrofluoric acid. In the film formation step, the metal oxide film is formed by any one of physical vapor deposition, chemical vapor deposition, and sol-gel method,
2. The method of manufacturing a liquid crystal device according to claim 1, wherein in the surface treatment step, the liquid crystal side surface of the metal oxide film is subjected to gas phase treatment with hydrogen fluoride. In the film formation step, the metal oxide film is formed by any one of physical vapor deposition, chemical vapor deposition, and sol-gel method,
2. The method of manufacturing a liquid crystal device according to claim 1, wherein, in the surface treatment step, a carbon electrode arc discharge treatment is performed on the liquid crystal side surface of the metal oxide film. In the film formation step, the step of forming the metal oxide film by physical vapor deposition or chemical vapor deposition,
Method of manufacturing a liquid crystal device according to claim 1, characterized in that the atom or group of plasma irradiation, or with any of the steps of the beam irradiation, continuously in a vacuum. In the film forming step,
Forming the metal oxide film by physical vapor deposition or chemical vapor deposition;
The method of manufacturing a liquid crystal device according to claim 1, wherein the carbon electrode arc discharge treatment step is continuously performed in a vacuum.

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