JP2001154611A - Active matrix device and method of producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an active matrix device and a liquid crystal display device in which a film of a reflection pixel electrode having good reflection characteristics can be formed and which is provided with a means to prevent decrease in the electric capacitance due to leaked light as well as to prevent decrease in the reflectance due to corrosion of the pixel electrode. SOLUTION: An active element 18 is formed on a silicon substrate 1, an insulating layer 6 is formed on the silicon substrate where the active element 18 is formed, the surface of the insulating layer 6 is flattened, and a reflection pixel electrode 7 is formed on the flattened insulating layer 6. Therefore, the film of the reflection pixel electrode 7 having good reflection characteristics can be formed by flattening, and decrease in the electric capacitance due to leaked light as well as decrease in the reflectance due to corrosion of the pixel electrode can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an active matrix device and a method of manufacturing the same, and more particularly, to a method of forming a reflective pixel electrode film having good reflection characteristics in an active matrix type reflection type liquid crystal display device. The present invention relates to means for preventing the deterioration of the reflective pixel electrode while maintaining the reflectance of the pixel electrode.

[0002]

2. Description of the Related Art A conventional reflection type liquid crystal display device using a reflection type liquid crystal display element is described in, for example, Japanese Patent Application Laid-Open No. 4-178625.

FIG. 7 is a sectional view showing an example of the structure of a conventional reflection type liquid crystal display device. In the conventional reflective liquid crystal display device, a voltage from the active matrix device 18 is applied to the pixel electrode 32. In addition to separating the pixel electrode 32 from the liquid crystal layer 9, the active matrix element 1
The pixel electrode 32 and the liquid crystal layer 9
A dielectric layer 33 and a dielectric mirror 34 are provided between them. The dielectric mirror 34 is made of a dielectric multilayer film. When the pixel electrode 32 and the liquid crystal layer 9 are separated in this manner, restrictions on materials that can be used for the pixel electrode 32 are relaxed.

In general, when a reflective surface is formed by using a metal for a pixel electrode of a reflective liquid crystal display element, the metal surface is corroded at an interface directly in contact with the liquid crystal, and the reflectance of the pixel electrode is reduced. Was. In addition, there is also a problem that the liquid crystal is deteriorated due to the corrosion, and unevenness in luminance and color is generated in a plane.

When the dielectric mirror 34 is used as a reflection surface and the pixel electrode 32 is spatially separated from the liquid crystal layer 9 instead of using a metal pixel electrode as a reflection surface as in the above-described conventional example, these problems are solved. It is solved temporarily.

[0006]

However, the conventional reflection type liquid crystal display device having a dielectric mirror still has a problem.
There were the following problems.

The dielectric mirror 34 is formed as a multilayer film in which thin films of materials having different refractive indexes such as titanium dioxide and silicon dioxide are alternately stacked. As the number of layers of the multilayer film increases, the reflectance of the dielectric mirror 34 increases, but the increase in the number of layers of the multilayer film involves a decrease in electric capacity.

The light leaked from the dielectric mirror 34 and transmitted therethrough is absorbed by the flattened dielectric layer 33 having a high visible light absorptivity formed between the dielectric mirror 34 and the pixel electrode 32. It has become.

As described above, in the prior art, between the liquid crystal 9 and the dielectric layer 33 formed on the pixel electrode 32,
Since the dielectric mirror 34 is disposed, and the voltage applied between the pixel electrode 32 and the transparent electrode 10 facing the pixel electrode 32 via the liquid crystal layer 9 is also applied to the dielectric mirror 34 in a shared manner. In addition, the effective applied voltage to the liquid crystal 9 decreases, and it becomes difficult to drive the liquid crystal element.

Further, when light leaking from the gap between the pixel electrodes 32 enters a circuit section such as the active matrix element 18, electric charges flow out of the storage capacitor, so-called light leakage occurs. Dielectric mirror 34 for preventing this light leak
There is a so-called trade-off between the effect of reflection of light and the adverse effect of lowering the effective applied voltage to the liquid crystal 9.

However, in the above-mentioned prior art, this trade-off relationship has not been considered. In addition, the process of forming the dielectric multilayer film is complicated and causes an increase in the cost of the reflective liquid crystal display device. Although a protective film for spatially separating the reflective pixel electrode and the liquid crystal layer is indispensable, a decrease in the reflectance of the reflective pixel electrode due to the protective film must be avoided.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for forming a film of a reflective pixel electrode having good reflection characteristics, preventing a decrease in electric capacity due to light leakage and preventing a decrease in reflectance due to corrosion of the pixel electrode. An object is to provide an active matrix element and a liquid crystal display element.

Another object of the present invention is to provide a process for forming a film of a reflective pixel electrode having good reflection characteristics, preventing a decrease in electric capacity due to light leakage and a decrease in reflectance due to corrosion of the pixel electrode. An object of the present invention is to provide a method for manufacturing an active matrix element and a liquid crystal display element including the same.

[0014]

According to the present invention, there is provided a semiconductor device comprising: a substrate; an active element provided on the substrate; an insulating layer provided on the active element and having a flat surface; And an active matrix element having a reflective pixel electrode provided on a flat insulating layer.

The present invention also provides a substrate, an active element provided on the substrate, an insulating layer provided on the active element and having a flat surface, and a reflective pixel provided on the flat insulating layer. An active matrix element having an electrode and a dielectric film provided on a reflective pixel electrode is proposed.

The present invention further provides a first substrate, an active element provided on the first substrate, and an insulating layer provided on the first substrate on which the active element is provided and having a flat surface. A reflective pixel electrode provided on an insulating layer having a flat surface; a dielectric film provided on the reflective pixel electrode;
And a liquid crystal display element having a liquid crystal layer sandwiched between a first substrate and a second substrate.

In order to achieve the above and other objects, the present invention provides a step of forming an active element on a substrate, a step of forming an insulating layer on a substrate provided with the active element,
A method for manufacturing an active matrix element, comprising: a step of planarizing a surface of an insulating layer; and a step of forming a reflective pixel electrode on the planarized insulating layer. Suggest.

The present invention also provides a step of forming an active element on a substrate, a step of forming an insulating layer on a substrate provided with the active element, a step of flattening the surface of the insulating layer, A method of manufacturing an active matrix element, including a step of forming a reflective pixel electrode on an insulating layer and a step of forming a dielectric film on the reflective pixel electrode.

According to the present invention, furthermore, a step of forming an active element on the first substrate, a step of forming an insulating layer on the first substrate provided with the active element, and flattening the surface of the insulating layer A step of forming a reflective pixel electrode on the planarized insulating layer; a step of forming a dielectric film on the reflective pixel electrode; and holding the liquid crystal layer between the first substrate and the opposing second substrate. And a method for manufacturing a liquid crystal display element including the steps of:

In the present invention, since the surface of the insulating layer is flattened and the reflective pixel electrode is formed on the flattened insulating layer, a stable reflective pixel electrode film can be formed and good reflection characteristics can be obtained. Can be

Further, as shown in FIG.
And the liquid crystal 9 are spatially separated by the single-layer dielectric film 8, so that the reflectance of the reflective pixel electrode 7 caused by corrosion of the reflective pixel electrode 7 caused when the reflective pixel electrode 7 contacts
The deterioration of the characteristics does not occur, and the reliability of the reflective liquid crystal display element is improved.

When a reflective liquid crystal display device is used as an image display device, it is desirable that the reflective liquid crystal display device has good reflection characteristics in the visible light region. Therefore, in the present invention, the thickness of the dielectric film 8 is set to a thickness at which the reflectance of white light obtained from the combination of the wavelength dispersion of the intensity of the incident light, the reflectance for each wavelength, and the human luminous efficiency curve is the highest. The thickness d was set.

Here, a process for obtaining a suitable thickness d of the dielectric film 9 will be described. Assuming that the refractive index of the liquid crystal is n ₁ , the refractive index of the dielectric film 8 is n ₂ , the complex refractive index of the reflective pixel electrode 7 is n ₃ , and the extinction coefficient is k ₃ , n ′ ₃ = n ₃ + ik ₃ In other words, the reflectance R of the reflective liquid crystal display element with respect to the irradiation light perpendicularly incident on the reflective pixel electrode 7 is expressed as follows, where λ is the wavelength. However, individual parameters are as shown in Expressions 2 to 5. From Equations 1 to 5, the wavelength dependence of the reflectance of the reflective liquid crystal display device can be obtained.

[0024]

(Equation 1)

[0025]

(Equation 2)

[0026]

(Equation 3)

[0027]

(Equation 4)

[0028]

(Equation 5) Further, using the human relative luminous efficiency characteristic curve V (λ) and the wavelength distribution I (λ) of the incident light intensity shown in FIG. The thickness dependency Ra (d) of the body film 8 is obtained. Where G
Means that integration is performed over the entire wavelength region of the incident light of the reflection type liquid crystal display element.

[0029]

(Equation 6) When the thickness d of the dielectric film 8 is increased from 0 nm, the interference between the reflected light at the interface between the dielectric film 8 and the liquid crystal 9 and the reflected light at the interface between the dielectric film 8 and the pixel electrode 7 causes ,
The reflectance Ra (d) of the obtained white light decreases, but when the film thickness d is further increased, the reflectance Ra eventually increases and reaches a maximum.
When the thickness d is further increased, the reflectance Ra of white light is again increased.
(d) decreases, but when the film thickness d increases, the reflectance Ra (d) increases again. As described above, as the thickness d of the dielectric film 8 increases, the reflectance Ra (d) of white light repeatedly increases and decreases.

The term contributing to the above-mentioned interference effect is the term cosine in Equation 1, specifically, β shown in Equation 5. The range of wavelength λ of visible light is from 380 nm to 700
nm, that is, 380 nm <λ <700 nm.
The refractive index n ₂ of the dielectric film 8 is about 2.0 1.5.

Therefore, when d≪λ, the variation width β of β in the visible light region is 2π or less, and as shown on the left of FIG. 3, the wavelength interval at which the reflectance R (λ) increases or decreases. Is about the same as the wavelength width in the visible light region. By making the maximum wavelength of the reflectance R (λ) coincide with the maximum wavelength of the relative luminous efficiency curve, the reflectance Ra (d) of white light can be increased.

On the other hand, when d≫λ, Δβ≫2π · n ₂ , and the term cosine in equation (1) greatly changes due to a slight change in the wavelength, and therefore the wavelength interval at which the reflectance R (λ) increases or decreases is narrow. In other words, as shown on the right side of FIG. 3, the reflectance R (λ) repeatedly increases and decreases many times in the visible light region.

Therefore, the product of the spectrum of the reflectance R (λ) and the spectral luminous efficiency curve (FIG. 2) for each wavelength is obtained, and integrated over the entire wavelength region of the light incident on the reflection type liquid crystal display element. The reflectance Ra (d) of white light is averaged to the center value of the amplitude, and gradually approaches the reflectance when the thickness of the dielectric film 8 is sufficiently thicker than the wavelength of the incident light. That is, the width of the increase / decrease in the reflectance Ra (d) of the white light decreases as the thickness d of the dielectric film 8 increases.

Usually, a region having a sufficient thickness as a protective film is
Although it is several tens nm or more, in this region, the reflectance Ra (d) of white light is higher than the reflectance when the film thickness d of the dielectric film 8 is sufficiently thicker than the wavelength of incident light. This is a film thickness region where the reflectance Ra (d) of white light is maximized.

In particular, the initial maximum value (first maximum value) when the film thickness d is increased from 0 is a value equivalent to the reflectance of white light when the dielectric film 8 is not applied due to the interference effect. In order to show, the film thickness d corresponding to the first maximum value is the most preferable as the film thickness of the dielectric film 8.

Since the dielectric film 8 is a single-layer film, the structure is simple, and a reflective liquid crystal display device can be manufactured easily and at low cost. Further, since the thickness of the dielectric film 8 is about the wavelength of the projection light, it is sufficiently thinner than the liquid crystal 9, and the reduction of the liquid crystal driving voltage due to the sharing of the capacitance to the dielectric film 8 is small.

[0037]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of an active matrix element, a reflection type liquid crystal display element and a liquid crystal display device according to the present invention will be described with reference to FIGS.

FIG. 1 is a sectional view showing the structure of an embodiment of the reflection type liquid crystal display device according to the present invention. The reflection type liquid crystal display device of the present embodiment uses a monolithic integrated circuit substrate on which an active matrix element 18 is formed as a reflection substrate, and a glass substrate 1 having this reflection substrate and a transparent electrode 10.
1, a polymer-dispersed liquid crystal 9 is sandwiched therebetween. The polymer-dispersed liquid crystal 9 is in a scattering state when no voltage is applied, and has a characteristic that the scattering property decreases and the transmission state changes as the applied voltage increases. The polymer-dispersed liquid crystal 9 does not require a polarizing film and an alignment film, and is a liquid crystal having high light use efficiency.

The reflective substrate is formed on a silicon substrate 1 as an active element for driving a liquid crystal by using a MOS (Metal Oxide Semiconductor).
onductor) transistor is formed. That is, the source diffusion layer 12 is formed on the p-type well 2 of the silicon substrate 1.
, A source electrode 3, a drain diffusion layer 14, a drain electrode 15, a polysilicon gate 13, and the like, form a MOS transistor. A first spin-on-glass insulating layer 16 is provided for interlayer insulation. Further, a light-shielding wiring layer 5 is provided via a second spin-on-glass insulating layer 4 in order to prevent light from entering the MOS transistor layer. An example of a structure in which the light-shielding wiring layer 5 is provided is as follows.
For example, it is already described in JP-A-6-194690,
This is enough to prevent light leakage.

As a material of the reflective pixel electrode 7, a metal having a good reflectance in a visible light region is preferable, and aluminum and silver are listed as candidates. Here, an example in which aluminum is used as the material of the reflective pixel electrode 7 will be described.

When the reflective pixel electrode 7 is formed on a flat surface, a stable film can be formed and good reflection characteristics can be obtained. Therefore, it is desirable that the silicon oxide layer 6 provided as a base of the reflective pixel electrode 7 be planarized by surface polishing.

The electric signal controlled by the MOS transistor is applied to the reflective pixel electrode 7 through the through-hole contact 17 and applies a drive voltage to the polymer dispersed liquid crystal 9 between the transparent pixel 10 and the opposing transparent electrode 10.

The dielectric film 8 provided as a protective film between the reflective pixel electrode 7 and the polymer-dispersed liquid crystal 9 is required to have good insulation properties and good transmission characteristics in the visible light region. , High dielectric constant, easy formation, etc.

One of the materials satisfying these conditions is silicon nitride. Silicon nitride has no absorption in the visible light region and shows very good transmission characteristics,
It is a material often used in semiconductor processes as an interlayer insulating film. The dielectric constant of silicon nitride is as high as about 9,
It is equivalent to the dielectric constant of the polymer dispersed liquid crystal 9. Further, the water permeability of the silicon nitride film is smaller than that of a silicon oxide film or the like, and is a suitable material for the protective film of the metal pixel electrode 7.

As a method of forming the silicon nitride film 8, a plasma-chemical vapor deposition (plasma-CVD) method, an electron cyclotron resonance-chemical vapor deposition (ECR-CVD) method,
A sputtering method is exemplified.

In this embodiment, the plasma-CVD method often used in the semiconductor process is used, but the silicon nitride film 8 having the same characteristics can be formed by the other two methods.

FIG. 4 shows calculated values of the dependency of white light reflectance on the silicon nitride film thickness in the reflection type liquid crystal display element of this embodiment in which silicon nitride is used as the material of the dielectric film 8 and relative luminous efficiency is taken into consideration. is there. Here, aluminum was used as the material of the reflective pixel electrode 7, and the refractive index of the liquid crystal was assumed to be 1.5.

According to FIG. 4, as the film thickness increases,
There is an increase or decrease in reflectivity. The film thickness at which the peak value of the reflectance is obtained is nd = m, where m is a natural number, n is the refractive index of silicon nitride, d is the thickness of the silicon nitride film, and λ is the wavelength of the incident light.
It can be roughly explained by λ / 2. As already described in the means for solving the problems, the reflectance of the reflective liquid crystal display element needs to be optimized in consideration of the relative luminous efficiency. If the complex refractive index of aluminum has wavelength dependence, the film thickness at which the peak value of the reflectance is obtained is nd = mλ / 2.
It is different from the film thickness required in the above.

The peak value of the reflectivity decreases as the thickness of the silicon nitride increases, and eventually becomes a constant value, about 85%.
become.

Under the condition that the thickness d of the silicon nitride is sufficiently small,
When the range of the film thickness where the reflectivity is larger than the constant value of 85%, that is, the range of the film thickness d where the reflectivity is maximal, is obtained.
70 nm, the second maximum being 230 nm to 300 nm
Is required.

In the region from 0 nm to 30 nm, the reflectivity is larger than a constant value of 85%, but the film thickness is difficult to form uniformly, and is outside the range where the dielectric film 8 can function as a protective film. Because it is, it was excluded here.

Further, taking into account that the peak value of the reflectance decreases as the thickness d of the silicon nitride increases and that the voltage applied to the liquid crystal decreases due to the sharing of capacitance, Considering that the refractive index of the silicon nitride film fluctuates due to
From 0 nm to 170 nm. Among them, 125 nm which is the film thickness corresponding to the maximum value of the reflectance of white light is the optimum film thickness.

Next, the effect of the capacitance sharing of the dielectric film 8 on the voltage applied to the liquid crystal will be considered. As described above, the dielectric constant of silicon nitride is about 9, and the dielectric constant of the liquid crystal 9 is equivalent to this. A typical thickness of the liquid crystal 9 is about 10 μm. Therefore, the decrease in the applied voltage of the liquid crystal due to the sharing of the capacity of the silicon nitride is at most 1%, and the influence on the display characteristics of the liquid crystal display element is extremely small.

When a potential difference occurs between the voltage of the counter electrode and the center voltage of the pixel electrode that is performing inversion on a frame-by-frame basis, a DC voltage is applied to the liquid crystal, and the difference in brightness between frames is called flicker. Occurs.

The dielectric film 8 has good insulating properties and has a capacity about 100 times larger than that of the liquid crystal 9.
It also functions as a DC component blocking capacitor for preventing the application of a DC voltage to the liquid crystal 9. Therefore, the dielectric film 8
Has the effect of preventing the occurrence of flicker, which is blinking synchronized with half the frame frequency.

FIG. 5 is a block diagram showing the configuration of an embodiment of a projection type liquid crystal display device using the reflection type liquid crystal display element of the present invention. In this liquid crystal display device, light emitted from a light source 19 is converted into a parallel light by a parabolic mirror 20, and then enters a dichroic prism 25 through a condenser lens 21, a mirror 22, a first diaphragm 23, and a lens 24. The dichroic prism 25 separates the incident light into three primary colors of red, blue, and green and emits the light. Dichroic prism 25
On the three side surfaces, a reflective liquid crystal display element 26 for red, a reflective liquid crystal display element 27 for green, and a reflective liquid crystal display element 28 for blue are arranged according to the emitted light, and light of each color is modulated by an image signal. I do. The modulated reflected light of each color is synthesized again by the dichroic prism 25, and is projected on the screen 31 via the lens 24, the second aperture 29, and the projection lens 30.

At this time, the three reflective liquid crystal display elements 2
6, 27 and 28 are in a state of scattering and reflection in accordance with an image signal for each pixel. Of these, the specularly reflected light is
The light is condensed at the position of the second stop 29 by the lens 24, passes through the second stop 29, passes through the projection lens 30, and passes through the screen 31.
Leads to. On the other hand, most of the scattered light is
Is not condensed at the position, and is almost blocked, and does not reach the screen 31.

Therefore, the three reflective liquid crystal display elements 2
A color image can be projected on the screen 31 according to the scattering and reflection states of 6, 27 and 28 by creating a light and dark state for each color.

According to the policy described below, the reflective liquid crystal display element 26 for red, the reflective liquid crystal display element 27 for green, and the blue liquid crystal display element 27 correspond to the wavelength range and relative luminous efficiency of the light incident on each reflective liquid crystal display element. When the thickness of the dielectric film in the reflective liquid crystal display element for use is optimized, the reflectance of each reflective liquid crystal display element is further increased, and the brightness of the projection type liquid crystal display device is further improved.

Here, as an example, a description will be given of a reflective liquid crystal display element using aluminum as the material of the reflective pixel electrode 7 and silicon nitride as the material of the dielectric film 8. The wavelength range of the light incident on the red reflective liquid crystal display element 26 is 580 nm or more, and the wavelength range of the incident light on the green reflective liquid crystal display element 27 is 490 nm to 580 nm.
nm, and the wavelength region of light incident on the blue reflective liquid crystal display element 28 is 490 nm or less.

FIG. 6 shows the reflectance R (d) for each wavelength region.
FIG. 9 is a characteristic diagram showing the result of obtaining. The thickness of the silicon nitride film in the reflectance of the reflective liquid crystal display element shown in FIG.
Comparing the reflectance at nm with the maximum value of each reflectance, if the silicon nitride film thickness of the red reflective liquid crystal display element 26 is 137 nm, the reflectance increases by 0.3%. When the thickness of the silicon nitride film of the green reflective liquid crystal display element 27 is 120 nm, the reflectance increases by 0.1%, and when the thickness of the silicon nitride film of the blue reflective liquid crystal display element 28 is 102 nm, 1. 9% increase in reflectance,
The projection type liquid crystal display device can be brightened.

[0062]

According to the present invention, since the surface of the insulating layer is flattened and the reflective pixel electrode is formed on the flattened insulating layer, a film of the reflective pixel electrode having good reflection characteristics can be formed. An active matrix device and a liquid crystal display device having means for preventing a decrease in electric capacity due to leakage and a decrease in reflectance due to corrosion of a pixel electrode can be obtained.

A single-layer dielectric film is formed between the reflective pixel electrode and the liquid crystal layer, and the thickness of the single-layer dielectric film is determined by the optical constant of the material of the reflective pixel electrode and the single-layer dielectric constant. Since it is determined according to the optical constant of the body film and the relative luminous efficiency, deterioration such as corrosion of the pixel electrode can be prevented without damaging the reflectance of the pixel electrode.

Further, the thickness of the dielectric is sufficiently smaller than the thickness of the liquid crystal layer, and the reduction of the liquid crystal driving voltage due to the sharing of the capacitance of the dielectric is small.

Since the dielectric film is a single layer, the structure is simple, and a reflective liquid crystal display device can be manufactured easily and at low cost.

[Brief description of the drawings]

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

FIG. 2 is a characteristic diagram showing a human relative luminous efficiency curve.

FIG. 3 is a characteristic diagram showing the wavelength dependence of the reflectance R (λ) when the relationship between the wavelength λ of incident light and the thickness d of a dielectric film is changed.

FIG. 4 is a characteristic diagram showing the film thickness dependence of the reflectance of the reflective liquid crystal display element with respect to the dielectric film when aluminum is used as the reflective pixel electrode and silicon nitride is used as the dielectric film.

FIG. 5 is a diagram showing a configuration of an embodiment of a liquid crystal display device using a reflective liquid crystal display element according to the present invention.

FIG. 6 shows a wavelength region 5 of incident light using aluminum as a reflective pixel electrode and silicon nitride as a dielectric film.
80 nm or more is red, and the wavelength range from 490 nm to 58
FIG. 7 is a characteristic diagram showing the dependence of the reflectance of a reflective liquid crystal display element on the thickness of a dielectric film when 0 nm is green and blue is 490 nm or less.

FIG. 7 is a cross-sectional view illustrating an example of the structure of a conventional reflective liquid crystal display device.

[Explanation of symbols]

 Reference Signs List 1 silicon substrate 2 p-type well 3 source electrode 4 second spin-on-glass insulating layer 5 light-shielding wiring layer 6 silicon oxide layer 7 reflective pixel electrode 8 dielectric film 9 polymer dispersed liquid crystal 10 transparent electrode 11 glass substrate 12 source diffusion layer 13 Polysilicon gate 14 Drain diffusion layer 15 Drain electrode 16 First spin-on-glass insulating layer 17 Through-hole contact 18 Active matrix element 19 Light source 20 Parabolic mirror 21 Condenser lens 22 Mirror 23 First stop 24 Lens 25 Cross dichroic prism 26 Red Reflective liquid crystal display element 27 Green reflective liquid crystal display element 28 Blue reflective liquid crystal display element 29 Second diaphragm 30 Projection lens 31 Screen 32 Pixel electrode 33 Dielectric layer 34 Dielectric mirror

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G02F 1/1335 520 G02F 1/1335 520 1/1343 1/1343 1/1368 1/136 500 (72) Invention Person: Kazuo Takemoto 3300 Hayano, Mobara City, Chiba Pref., Electronic Device Division, Hitachi, Ltd.

Claims (6)

[Claims] A substrate; an active element provided on the substrate; an insulating layer provided on the active element and having a flat surface; and a reflective pixel electrode provided on the flat surface of the insulating layer. An active matrix element having: 2. A substrate; an active element provided on the substrate; an insulating layer provided on the active element and having a flat surface; and a reflective pixel electrode provided on the flat insulating layer. And an active matrix element having a dielectric film provided on the reflective pixel electrode. A first substrate; an active element provided on the first substrate; an insulating layer provided on the first substrate on which the active element is provided and having a flat surface; A reflective pixel electrode provided on an insulating layer having a flat surface; a dielectric film provided on the reflective pixel electrode; a second substrate; and a portion between the first substrate and the second substrate. A liquid crystal display element having a liquid crystal layer sandwiched between the liquid crystal display elements. A step of forming an active element on the substrate; a step of forming an insulating layer on the substrate provided with the active element; a step of flattening a surface of the insulating layer; Forming a reflective pixel electrode on the insulating layer. 5. A step of forming an active element on a substrate; a step of forming an insulating layer on the substrate provided with the active element; a step of flattening a surface of the insulating layer; A method for manufacturing an active matrix element, comprising: forming a reflective pixel electrode on the insulating layer; and forming a dielectric film on the reflective pixel electrode. 6. A step of forming an active element on a first substrate, a step of forming an insulating layer on the first substrate provided with the active element, and a step of flattening a surface of the insulating layer A step of forming a reflective pixel electrode on the planarized insulating layer; a step of forming a dielectric film on the reflective pixel electrode; and a liquid crystal layer formed by the first substrate and the opposing second substrate. And a step of sandwiching the liquid crystal display element.