JP2000047165A - Manufacture of reflective liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a reflective liquid crystal display for improving adhesive strength of a metal reflective electrode to a lower substrate. SOLUTION: In a manufacturing method of a reflective liquid crystal display which comprises forming an electrode pattern of a transparent electrode 16 on an upper substrate 13, forming an alignment film 14 further thereon, forming an electrode pattern of a two-layer film metal reflective electrode comprising a Ti electrode 21 and an A1 alloy electrode 20 on a lower substrate 19, successively forming an electrode protective insulating film 9 and an alignment film 15 with heat treatment further thereon, placing the alignment films 14 and 15, each formed on the upper and lower substrates 13 and 19 respectively opposite to each other, providing a liquid crystal cell by holding liquid crystal 17 between the upper and lower substrates 13 and 19 and connecting electronic parts for driving the liquid crystal cell with the cell, a heating temperature is set at <=260 deg.C at the time of forming the electrode protective insulating film 9 and the alignment film 15 with heat treatment on the lower substrate 19. Then soda-lime glass, on which a SiO2 film is formed, is used as a material for the upper and/or lower substrates 13 and/or 19.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a reflection type liquid crystal display device having a reflection electrode.

[0002]

2. Description of the Related Art A conventional reflection type liquid crystal display device is of a TN or STN mode, and comprises two substrates on which transparent electrodes are formed and a liquid crystal cell disposed between the two substrates and holding a liquid crystal. The liquid crystal cell includes a pair of polarizers disposed on both sides of the liquid crystal cell, and a reflector disposed on the lower substrate outside the polarizer. However, in this configuration, the light passes through the polarizer 4 times.
The display is dark because it passes around. The transmittance of one polarizing plate is at most about 45%, and at this time, the transmittance of polarized light parallel to the absorption axis of the polarizing plate is almost 0%, and the transmittance of perpendicular polarized light is about 90%. Therefore, in this configuration, the reflectance is
(0.9) ⁴ × 50% = 32.8%. The reflectance is that of a black and white panel, and reaches a plateau at about 33%. In the case of a color liquid crystal display panel in which a color filter is formed on one substrate in the structure of the monochrome panel, the display is darker than the monochrome panel because light is further absorbed by the color filter. Therefore, it is difficult to secure the brightness as a reflective display.

In order to brighten the display, there have been proposed some configurations in which only one polarizing plate is provided above the liquid crystal cell, and the liquid crystal cell is sandwiched between one polarizing plate and a reflector.
(For example, Patent Publication: Hei 07-146469, Patent Publication: Hei 07-84252) In this case, two polarizing plates are used.
Because it passes only once, the reflectance of the black and white panel is (0.9)
² × 50% = 40.5%, which is expected to improve the reflectance by about 23.5% with respect to the configuration of two polarizing plates.

[0004] In addition, a PCGH mode reflection type liquid crystal display panel (see H. Seki: 1996SID, P.614SID96DIGEST) has been proposed as a configuration not using a polarizing plate in order to make the display brighter. The reflectance of this configuration as a monochrome panel is about 66%, and bright display can be expected.

In the configuration using one polarizing plate or no polarizing plate proposed as described above, in order to solve the problem such as parallax due to the thickness of the substrate between the reflecting plate and the liquid crystal, the reflecting plate is used. A metal reflective electrode also serving as an electrode is formed on the lower substrate, and is arranged as a reflector in the liquid crystal cell. Al with high reflectivity as metal reflective electrode
It is practical to include a film whose main component is.
(For example, Japanese Patent Application No. 09-208902) In manufacturing a conventional liquid crystal display device, an electrode protection insulating film having high hardness is formed between at least one electrode of the upper substrate and the lower substrate and the alignment film. Is done. This electrode protection insulating film prevents the alignment film from being broken by foreign matter or spacers mixed in the liquid crystal cell, and prevents the upper and lower electrodes from being in an electrical short state. The formation of the electrode protection insulating film is performed by a printing method which is advantageous in terms of productivity and cost.
It is formed by the following heat treatment. This is because the heat treatment at 350 ° C. or higher increases the resistance of the transparent electrode ITO. By the way, as a material of the electrode protection insulating film, for example, a material mainly composed of a silica oligomer, a zirconia oligomer, and a titania oligomer is used.
A heat treatment at about 00 ° C. is used in combination for copolymerization to form a high hardness inorganic insulating film. Further, the alignment film is formed by a printing method which is advantageous in terms of productivity and cost. Polyimide is applied by printing and formed by heat treatment at 180 to 300 ° C. for use.

[0006]

However, at least A
When the electrode protection insulating film and the alignment film are formed by heat treatment on the lower substrate having the metal reflective electrode including the film mainly containing l, the lower substrate and the film mainly containing Al alloy are included. Since there is a difference in the thermal expansion coefficient between the metal reflection electrode and the metal reflection electrode, there is a problem that internal stress due to heat is generated in the metal reflection electrode, and the adhesion between the lower substrate and the metal reflection electrode is reduced. As described above, when the adhesion between the lower substrate and the metal reflective electrode is reduced, the seal for bonding the upper substrate and the lower substrate, and the terminal portion of the liquid crystal cell to which the electronic components for driving the liquid crystal cell are connected, This means that the resistance to mechanical external force such as vibration is not sufficient.

According to the present invention, a method of manufacturing a reflection type liquid crystal display device having high adhesion between a metal reflection electrode and a lower substrate has been conventionally considered in consideration of the problem that adhesion between the metal reflection electrode and the lower substrate is poor. The purpose is to provide.

Another object of the present invention is to provide a method of manufacturing a reflective liquid crystal display device having high electromigration resistance and corrosion resistance.

[0009]

According to a first aspect of the present invention (corresponding to claim 1), an electrode pattern of a transparent electrode is formed on an upper substrate, and an alignment film is further formed thereon. Is formed on the lower substrate, and an electrode pattern of a metal reflective electrode including a film containing at least Al as a main component is formed on the lower substrate, and an electrode protection insulating film and an alignment film are further formed thereon by heating and sequentially formed. A liquid crystal cell is provided in which the alignment films formed on the upper substrate and the lower substrate are opposed to each other, and liquid crystal is sandwiched between the upper substrate and the lower substrate.
A method of manufacturing a reflection type liquid crystal display device for connecting an electronic component for driving the liquid crystal cell to the liquid crystal cell, wherein the electrode protection insulating film and the alignment film are formed on the lower substrate by heat treatment. A method for manufacturing a reflective liquid crystal display device, wherein a heating temperature is set to a temperature of 260 ° C. or lower.

As described above, by setting the heating temperature of the lower substrate to 260 ° C. or less when the electrode protective insulating film and the alignment film are formed by heating, the adhesion between the metal reflective electrode and the substrate is reduced. It is possible to obtain a reflective liquid crystal display device having high performance.

According to a second aspect of the present invention (corresponding to claim 2), the first aspect
In the method for manufacturing a reflective liquid crystal display device according to the present invention, the metal reflective electrode is formed by sequentially forming Ti and an Al alloy.
A method for manufacturing a reflection type liquid crystal display device characterized by being a layer film.

By providing Ti under the Al alloy as a metal reflective electrode, a reflective liquid crystal display device having high electromigration resistance and corrosion resistance can be obtained.

A third aspect of the present invention (corresponding to claim 3) is the first aspect of the present invention.
Alternatively, in the method for manufacturing a reflective liquid crystal display device according to the second aspect of the present invention, the upper substrate and / or the lower substrate
A method of manufacturing a reflection type liquid crystal display device, which is a soda lime glass having an SiO ₂ film formed thereon.

As described above, when soda-lime glass on which an SiO ₂ film is formed is used as at least one of the upper substrate and the lower substrate, the soda-lime glass is an inexpensive glass substrate. Can be manufactured at low cost.

A fourth aspect of the present invention (corresponding to claim 4) is the first aspect of the present invention.
The method of manufacturing a reflective liquid crystal display device according to any one of the first to third aspects, wherein the electrode protection insulating film is an inorganic insulating film.

As described above, when the electrode protection insulating film is an inorganic insulating film, it is possible to provide a reflection type liquid crystal display device which suppresses an electrical short between upper and lower electrodes.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to FIGS.

(Embodiment 1) FIG. 1 is a sectional view of a reflection type liquid crystal display device according to Embodiment 1 of the present invention. 10 is a polarizing plate, 11 is a polymer film, 12 is a scattering film, 1
3 is an upper substrate, 14 and 15 are alignment films, 16 is a transparent electrode,
17 is a liquid crystal, 18 is a seal, 19 is a lower substrate, 20 is A
1 alloy electrode, 21 is a Ti electrode, 9 is an electrode protection insulating film, 2
2 denotes an acrylic resin, 23 denotes an anisotropic conductive adhesive, 24 denotes a TAB tape carrier, 25 denotes an LSI chip, and 26 denotes a printed circuit board.

FIG. 2 is a cross-sectional view of a state in which a metal reflective electrode is formed on the lower substrate 19 of FIG. 1, and is a cross-sectional view when viewed from the side corresponding to the left side surface of FIG. 28 is a soda lime glass substrate, 27 is a SiO ₂ film, 21 is a Ti film,
Reference numeral 20 denotes an Al alloy film. The lower substrate 19 has a soda-lime glass substrate 28 on which an SiO ₂ film 27 is formed. S on soda-lime glass substrate 28
The formation of the iO ₂ film 27 is for preventing alkali elution from the soda lime glass substrate 28 to the liquid crystal 17. On this lower substrate 19, a Ti film and an Al alloy film are sequentially laminated by DC magnetron sputtering using an Al alloy target and a Ti target, and then a predetermined portion remains using a photoresist. It was patterned and etched as described above to obtain a two-layer film specular reflection type metal reflection electrode. On the lower substrate 19, no thin-film active element such as a transistor is formed.

The upper substrate 13 is a soda-lime glass substrate on which a SiO ₂ film is formed in the same manner as the lower substrate 19, and the transparent electrode 16 is formed of indium tin oxide. On the upper substrate 13, no thin film active element such as a transistor is formed.

Next, a metal reflective electrode composed of a Ti film 21 and an Al alloy film 20 is formed on the lower substrate 19 described above, and further, TA-60 manufactured by Catalyst Chemical Industry Co., Ltd.
6 was printed, heat-treated at 80 ° C. and temporarily cured, and then UV-irradiated at 6000 mJ / cm ² , and further cured at 250 mJ / cm ^2.
A heat treatment was performed at ℃ to form an electrode protection insulating film 9 of an inorganic insulating film made of SiO ₂ , TiO ₂ , and ZrO ₂ .

In this manner, the transparent electrode 16 is formed on the upper substrate 13 and further on the lower substrate 1
9, an electrode protection insulating film 9 is formed thereon, and further thereon,
After printing a 5 wt% solution of N-methyl-2-pyrrolidinone of polyimide and curing at 200 ° C.,
Alignment films 14 and 15 were formed by performing an alignment treatment by a rotational rubbing method using rayon cloth so as to realize a 50 ° twist STN mode liquid crystal 17.

In the peripheral portion on the upper substrate 13, 5.
A thermosetting sealing resin mixed with 1.0 wt% of glass fiber having a diameter of 5 μm is printed, and on the lower substrate 19, 5.
Resin beads having a diameter of 0 μm were sprayed at a rate of 200 beads / mm ² , the upper substrate 13 and the lower substrate 19 were bonded to each other, and the sealing resin was cured at 150 ° C. And △ n
A liquid crystal 17 obtained by mixing a predetermined amount of chiral liquid crystal with an ester nematic liquid crystal having an _{LC of} 0.16 was vacuum-injected, sealed with an ultraviolet curable resin, and then cured with ultraviolet light.

The upper substrate 1 of the liquid crystal cell thus formed
On top of 3, No. 3, a scattering film 12 having a scattering direction of 0 ° to 50 ° as measured from the film normal was bonded, which is a forward scattering film (trade name: Lumisty) manufactured by Sumitomo Chemical Co., Ltd. Further, a polymer film 11 of polycarbonate was stuck thereon. The polymer film 11 is composed of two polymer films having different slow axes. The polymer film on the liquid crystal cell side has a retardation of 0.3 μm and the slow axis is 90 ° with respect to the orientation direction of the upper substrate 13. The upper polymer film has a retardation of 0.5 μm and a slow axis of 45 ° with respect to the orientation direction of the upper substrate 13. In addition, neutral gray polarizing plates (Sumitomo Chemical Industries, Ltd.)
SQ-1852AP) and an anti-glare (AG) -treated polarizing plate 10 were attached so that the absorption axis coincided with the lower slow axis of the polymer film 11.

Further, the electronic components for driving the liquid crystal cell include a printed board 26 on which the electronic components are mounted, an LSI
The printed board 26 and the TAB tape carrier 24 were connected using the TAB tape carrier 24 on which the chip 25 was mounted, and the electrodes of the liquid crystal cell and the TAB tape carrier 24 were connected via the anisotropic conductive adhesive 23.

Further, the exposed part of the electrode between the electrode part and the display part where the electronic parts for driving the liquid crystal cell are connected via the anisotropic conductive adhesive 23 is formed by a TU manufactured by Hitachi Chemical Co., Ltd.
It was covered with an acrylic resin 22 called FFY (TF1141).

With this configuration, simple matrix driving with a duty ratio of 1/240, an achromatic black display with a low reflectance, an achromatic white display with a high reflectance, and an achromatic color from black to white. A normally black mode reflective liquid crystal display device capable of changing display was obtained.

In the above-described example, when the reflective liquid crystal display device is manufactured, the Ti film 21 and the Al film are formed on the lower substrate 19.
After forming the metal reflective electrode made of the alloy film 20, the heat treatment temperature for forming the electrode protection insulating film 9 is 250 ° C., and the heat treatment temperature for forming the alignment film 15 is 20 ° C.
It was assumed to be 0 ° C. However, here, a sample in which the heat treatment temperature when forming the electrode protection insulating film 9 was set to other than 250 ° C. and a sample in which the heat treatment temperature when forming the alignment film 15 was set to other than 200 ° C. The relationship between the heat treatment temperature and the adhesion between the metal reflective electrode and the lower substrate 19 was examined, and will be described below.

First, the relationship between the heat treatment temperature when forming the electrode protection insulating film 9 and the adhesion between the metal reflective electrode and the lower substrate 19 will be described.

On the lower substrate 19, a Ti film 21 and Al
After the metal reflective electrode made of the alloy film 20 is formed, the heat treatment temperature when forming the electrode protection insulating film 9 is set to 200.
℃, 210 ℃, 220 ℃, 230 ℃, 240 ℃, 250
° C, 260 ° C, 270 ° C, 280 ° C, 290 ° C, 300 ° C
C. and 310 ° C., and heat treatment was performed in air at each heat treatment temperature for 1 hour. Then, a cross-cut tape method (paint general test method JIS K5) was applied to the sample for each heat treatment.
400), the adhesion between the lower substrate 19 and the metal reflective electrode was evaluated. As a result, at a heat treatment temperature of 260 ° C. or less, the metal reflective electrode did not peel off, and the adhesion between the lower substrate 19 and the metal reflective electrode was good. However, 270
At a heat treatment temperature of 280 ° C. or 280 ° C., peeling of the metal reflective electrode occurs at 10 to 30%. At a heat treatment temperature of 290 ° C. to 310 ° C., peeling of the metal reflective electrode occurs at 50% or more. Adhesion with the reflective electrode was reduced.

Next, when the adhesion between the lower substrate 19 and the metal reflection electrode is good in the heat treatment for forming the electrode protection insulating film 9, the alignment film 15 is formed on the lower substrate 19.
The relationship between the heat treatment temperature at the time of forming the substrate and the adhesion between the metal reflective electrode and the lower substrate 19 will be described.

Also in this case, the heat treatment temperature for forming the alignment film 15 is set to 200 ° C., 210 ° C., 220 ° C., 23 ° C.
0 ° C, 240 ° C, 250 ° C, 260 ° C, 270 ° C, 28
0 ° C, 290 ° C, and 300 ° C.
Heat treated in air for hours. Then, for the sample for each heat treatment, the crosscut tape method (paint general test method J
IS K 5400) was used to evaluate the adhesion between the lower substrate 19 and the metal reflective electrode. As a result, the relationship between the heat treatment temperature at the time of forming the alignment film 15 and the adhesion between the metal reflective electrode and the lower substrate 19 depends on the above-described electrode protection insulating film 9.
It was found that the relationship was similar to the relationship between the heat treatment temperature at the time of forming the pattern and the adhesion between the metal reflective electrode and the lower substrate 19. That is, only at the heat treatment temperature of 260 ° C. or less, the metal reflective electrode did not peel off, and it was found that the adhesion between the lower substrate 19 and the metal reflective electrode was good.

The electrode protection insulating film 9 and the alignment film 15
In the configuration of the reflection type liquid crystal display device of FIG. 1 described above, the reflection is performed under the environment of the temperature of 60 ° C. and the humidity of 90% RH by using the metal reflective electrode in the case where the heat treatment at 260 ° C. or less is performed. The liquid crystal display device was subjected to a power-on test of 500 h to evaluate the electromigration resistance and the corrosion resistance of the electrodes. As a result, there is no abnormality such as disconnection in the metal reflective electrode when the heat treatment is performed at 260 ° C. or less,
No abnormalities on the surface were observed. From this result, 26
In the metal reflective electrode when the heat treatment was performed at 0 ° C. or lower, high reliability was obtained in terms of electromigration resistance and corrosion resistance.

From the above results, in the metal electrode having the above structure, when the heat treatment temperature at the time of forming the electrode protection insulating film 9 and the alignment film 15 is 260 ° C. or less, the lower substrate 19 and the metal reflective electrode are A reflective liquid crystal display device having high adhesion can be obtained. In addition, Ti, A
By using a two-layered film in which a 1 alloy is sequentially formed, a highly reliable reflective liquid crystal display device with high electromigration properties and corrosion resistance can be obtained.

Hereinafter, in the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals.

(Embodiment 2) FIG. 3 is a sectional view of a reflection type liquid crystal display device according to Embodiment 2 of the present invention. The reflection type liquid crystal display device according to the second embodiment is similar to that of the first embodiment.
Although the configuration is almost the same as that of the reflective liquid crystal display device of the first embodiment, the mounting method of the electronic components for driving the liquid crystal cell is the TAB mounting method in the first embodiment, whereas the second embodiment is the COG mounting method in the second embodiment. The difference is in the method. The printed circuit board 26 on which the electronic components are mounted, the flexible substrate 29, and the LSI chip 25 are used to connect the printed circuit board 26 and the flexible substrate 29, and the electrodes of the liquid crystal cell and the flexible substrate 29 are anisotropically connected. The connection was made via the conductive adhesive 23, and further, the electrode of the liquid crystal cell and the LSI chip 25 were connected via the anisotropic conductive adhesive 23.
Further, an exposed portion of the electrode between the electrode portion to which the flexible substrate 29 as an electronic component for driving the liquid crystal cell was connected and the display portion was covered with the acrylic resin 22.

In the configuration of the second embodiment,
/ 240 duty ratio simple matrix drive, normally black mode with low reflectance and achromatic black display, high reflectance with achromatic white display, and display that changes from black to white in achromatic color Was obtained.

By the way, as described in the first embodiment, the adhesion between the lower substrate 19 of the reflection type liquid crystal display device of the second embodiment and the metal reflective electrode is also improved in the reflection type liquid crystal display device of the first embodiment. At a heat treatment temperature of 260 ° C. or lower, a reflective liquid crystal display device having high adhesion between the lower substrate 19 and the metal reflective electrode can be obtained. Further, a metal reflective electrode was formed by sequentially forming Ti and an Al alloy.
With the configuration of the layer film, a highly reliable reflective liquid crystal display device with high electromigration and corrosion resistance can be obtained.

In the first and second embodiments, the metal reflective electrode is a two-layer metal reflective electrode in which Ti and Al alloys are sequentially formed. Any reflective electrode may be used. Even in such a case, by setting the heat treatment temperature at the time of forming the electrode protection insulating film 9 and the alignment film 15 to 260 ° C. or lower, a reflective liquid crystal display device having high adhesion between the metal reflective electrode and the lower substrate 19 can be obtained. Obtainable.

In the first and second embodiments, the upper substrate 13 and the lower substrate 19 on which thin-film active elements such as transistors are not formed are used. An electrode unit for connecting electronic components for driving the display unit and an electrode unit between the display electrode unit and an electrode unit for connecting the electronic component for driving the liquid crystal cell are metal reflective electrodes, and the metal reflective electrode is As long as it is a two-layer film in which a Ti film and an Al alloy film are sequentially formed, a substrate on which a thin film active element is formed may be used as the upper substrate 13 and the lower substrate 19.

In the first and second embodiments, the soda lime glass substrate on which the SiO ₂ film is formed is used as the upper substrate 13 and the lower substrate 19, but an alkali-free glass substrate may be used.

In the first and second embodiments, an inorganic insulating film is used as the electrode protection insulating film 9, but an organic insulating film may be used. However, as the electrode protection insulating film 9, a high hardness inorganic insulating film is preferable from the viewpoint of suppressing an electrical short between the upper and lower electrodes.

In the first and second embodiments, the mirror type is used as the metal reflective electrode, and the scattering film 12 is arranged on the upper substrate 13. However, the metal reflective electrode is made a scattering type without using the scattering film. Is also good.

In the first and second embodiments, a reflection type liquid crystal display device for monochrome display is used as the reflection type liquid crystal display device. May be used as the reflection type liquid crystal display device.

Further, in the first and second embodiments,
Although the STN mode liquid crystal is used, the TN mode or PCGH
By using another liquid crystal mode such as a mode, a configuration of a reflective liquid crystal display device in which a polarizing plate, a polymer film, or the like is adjusted to the liquid crystal mode may be adopted.

[0046]

As is apparent from the above description, the present invention can provide a method of manufacturing a reflection type liquid crystal display device having high adhesion between a metal reflective electrode and a lower substrate.

Further, the present invention can provide a method for manufacturing a reflection type liquid crystal display device having high electromigration resistance and corrosion resistance.

Further, the present invention can provide a method of manufacturing a reflection type liquid crystal display device using an inexpensive glass substrate.

Further, the present invention can provide a reflection type liquid crystal display device which suppresses an electrical short between electrodes provided on the upper substrate and the lower substrate, respectively.

[Brief description of the drawings]

FIG. 1 is a sectional view of a reflective liquid crystal display device according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing a state in which a metal reflective electrode is formed on the lower substrate according to the first embodiment of the present invention;

FIG. 3 is a sectional view of a reflective liquid crystal display device according to a second embodiment of the present invention.

[Explanation of symbols]

Reference Signs List 9 electrode protection insulating film 10 polarizing plate 11 polymer film 12 scattering film 13 upper substrate 14, 15 alignment film 16 transparent electrode 17 liquid crystal 18 seal 19 lower substrate 20 Al alloy electrode, Al alloy film 21 Ti electrode, Ti film 22 acrylic Resin 23 Anisotropic conductive adhesive 24 TAB tape carrier 25 LSI chip 26 Printed circuit board 27 SiO ₂ film 28 Soda lime glass substrate 29 Flexible substrate

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Ogawa Tetsudo 1006 Kazuma Kadoma, Osaka Pref. Matsushita Electric Industrial Co., Ltd. KA18 KB13 KB24 NA18 PA02 PA08 PA11 QA07 QA08 QA10

Claims (4)

[Claims] An electrode pattern of a transparent electrode is formed on an upper substrate, an alignment film is further formed thereon, and an electrode of a metal reflective electrode including at least a film mainly composed of Al is formed on the lower substrate. Forming a pattern, further heat-treating an electrode protection insulating film and an alignment film thereon to sequentially form an alignment film formed on each of the upper substrate and the lower substrate; And a liquid crystal cell sandwiching liquid crystal between the lower substrate and a liquid crystal cell, and a method of manufacturing a reflective liquid crystal display device in which electronic components for driving the liquid crystal cell are connected to the liquid crystal cell. A method for manufacturing a reflection type liquid crystal display device, wherein a heating temperature of forming an electrode protection insulating film and the alignment film by heat treatment is set to 260 ° C. or less. 2. The method according to claim 1, wherein the metal reflective electrode is a two-layer film in which Ti and an Al alloy are sequentially formed. 3. The method according to claim 1, wherein the upper substrate and / or the lower substrate is soda lime glass on which an SiO ₂ film is formed. 4. The method for manufacturing a reflective liquid crystal display device according to claim 1, wherein said electrode protection insulating film is an inorganic insulating film.