JPH10339873A - Manufacture of liquid crystal display device - Google Patents

Abstract

(57) [Problem] To provide a method of manufacturing a reflective liquid crystal display device having a large reflectivity and capable of transmitting light effectively even when combined with a Schlieren optical system. An individual switch and an individual electrode are provided for each pixel.
And a counter substrate 1 facing the matrix substrate with a liquid crystal material 104 interposed therebetween.
06, after forming an individual switch on the matrix substrate 101, covering the entire surface of the individual switch with an insulating film, and contacting the insulating film with the individual switch. Forming a hole, forming a concave portion for embedding the individual electrode, depositing the material of the individual electrode as a whole, polishing the material of the individual electrode, and planarizing the material of the individual electrode on the same surface as the insulating layer; Further, two types of dielectric films are alternately formed on the flattened individual electrodes to form a dielectric mirror 10.
3 is formed.

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 liquid crystal display device used for a projector, a display, and the like.

[0002]

2. Description of the Related Art Conventionally, a liquid crystal display device using a scattering type liquid crystal, which is called a polymer dispersed liquid crystal or a polymer network liquid crystal, has a refractive index of a randomly arranged liquid crystal and a refractive index of a surrounding polymer. By applying a voltage between the light scattering state due to the difference and the electrode sandwiching the liquid crystal layer, the alignment direction of the liquid crystal is aligned. doing. The liquid crystal display device is used in combination with a so-called schlieren optical system in order to further increase the change in the amount of light due to the scattering state and the transmission state. The schlieren optical system passes out of the light from the liquid crystal display element, outgoing light of a limited angle or less by the stop, and conversely, outgoes outgoing light of the angle or more limited by the stop. For this reason, when the incident light is substantially parallel light, when the liquid crystal display element is in a scattering state, the amount of the incident light which is emitted while changing the direction largely from the incident direction increases. Therefore, the emitted light is blocked by the schlieren optical system. On the other hand, when the liquid crystal display element is in the transmission state, the incident light is emitted without changing the emission angle by passing through the liquid crystal display element. At this time, the emitted light can be transmitted without being blocked by the Schlieren optical system. By the way, in order for the liquid crystal display element to perform a display, the state of the liquid crystal is controlled by a plurality of individual electrodes divided on a display surface to form a display. In order to increase the degree of freedom of display, a matrix type is used in which individual electrodes are formed in a regular arrangement on a display surface and a display is formed by selecting individual electrodes.

[0003]

However, in the above conventional example, when a high-definition image is displayed on the liquid crystal display element and the size of the liquid crystal display element is reduced, the density of the individual electrodes increases and the individual electrodes increase. The period at which the electrodes are formed becomes several tens of microns. As described above, when the period of the individual electrodes becomes narrow, the emitted light in the transmission state of the liquid crystal display element causes a diffraction phenomenon due to the periodic structure of the individual electrodes. For this reason, the incident light becomes outgoing light including diffracted light having an angle with the incident direction. In a reflective liquid crystal display element that emits incident light in a substantially incident direction, reflective electrodes are arranged in a matrix as individual electrodes. Therefore, when the schlieren optical system is used, there is a drawback that a part of the emitted light is blocked not only in the scattering state of the liquid crystal display element but also in the transmission state.

Accordingly, it is an object of the present invention to solve the above problems and to provide a method of manufacturing a reflection type liquid crystal display device having a large reflectance and capable of transmitting light effectively even when combined with a Schlieren optical system. The purpose of.

[0005]

Means for Solving the Problems In order to solve the above-mentioned problems, the present inventors have made intensive efforts and, as a result, have obtained the following invention. That is, the method for manufacturing a liquid crystal display device of the present invention is directed to a reflection type liquid crystal display device having a matrix substrate provided with individual switches and individual electrodes for each pixel, and a counter substrate facing the matrix substrate with a liquid crystal material interposed therebetween. In the manufacturing method, after forming an individual switch on the matrix substrate, the entire surface of the individual switch is covered with an insulating film, and a contact hole connected to the individual switch is formed in the insulating film, and a recess for embedding the individual electrode is formed. Forming, depositing the material of the individual electrode as a whole, polishing the material of the individual electrode, and planarizing the material on the same surface as the insulating layer; Forming a dielectric mirror by alternately forming dielectric films. Here, the material of the individual electrode is desirably polished by a chemical mechanical polishing method.

According to the present invention, since the reflective electrode covers the entire display surface and no diffraction phenomenon occurs, the emitted light in the transmission state of the liquid crystal display element goes straight. The schlieren optical system can be efficiently transmitted.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION

(Embodiment 1) An embodiment of the present invention will be described with reference to FIG. On the matrix substrate 101, semiconductor switch rows arranged in a matrix (not shown) for applying a voltage to the individual electrodes 102 are formed. In this embodiment, a MOS transistor is formed on a silicon substrate to form an individual electrode 102 composed of an aluminum electrode.

In the individual electrode, a contact hole for connection to the drain terminal of the MOS transistor and a concave portion for burying the individual electrode are formed in an insulating layer formed on the MOS transistor formed below. Aluminum for forming an individual electrode is formed on the insulating layer by sputtering so as to fill the recess.

Then, the aluminum other than the concave portion of the insulating layer is CM
Removed by P polishing technique. With this polishing technique, aluminum can be selectively polished, and excess aluminum can be polished to eliminate a step with an insulating layer and form a flat surface. On the flat surface, 27 layers of SiO ₂ layers and TiO ₂ layers were alternately laminated as dielectric mirrors to form a layer having reflectivity over the entire visible range.

A transparent substrate 106 on which an ITO film is formed is prepared as the transparent electrode 105, and a mixture of liquid crystal and monomer is sandwiched between the matrix substrate and the transparent substrate.

Ultraviolet rays are irradiated from the transparent substrate side to form a scattering type liquid crystal 104 in which a liquid crystal and a polymer resin are mixed.

(Embodiment 2) In Embodiment 2, Embodiment 1
Similarly, the individual electrodes 102 are formed on the matrix substrate 101.

The individual electrodes are formed by aluminum CMP as in the first embodiment. In the second embodiment, the reflectance of the dielectric mirror is not limited to the entire visible light range, but is limited to the incident light. SiO ₂ and TiO ₂ are nd with respect to the wavelength λ of the incident light.
= Λ / 4.

For example, when λ = 550 nm, nd = 137n
5 to 6 layers of m ₂ SiO ₂ and TiO ₂ are formed. With this dielectric mirror, the reflectance can be increased centering on the wavelength of λ = 550 nm. Good display can be obtained by using light centered on green light as incident light.

[0015]

As described above, according to the present invention,
Since the dielectric mirror is formed after the individual electrodes are flattened, a flat reflecting surface with high reflectance can be obtained. This reflective surface is electrically divided by the lower individual electrodes, but the entire display surface constitutes a reflective surface, so that incident light is not scattered due to diffraction and the incident light is reflected well. Thus, light can be transmitted effectively even in combination with the schlieren optical system. From this, a bright display can be realized when the projector is configured.

[Brief description of the drawings]

FIG. 1 is a sectional view of a liquid crystal display device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 101 Matrix substrate 102 Individual electrode 103 Dielectric mirror 104 Scattering liquid crystal 105 Transparent electrode 106 Transparent substrate

Claims (2)

[Claims] 1. A method of manufacturing a reflection type liquid crystal display device comprising: a matrix substrate having an individual switch and an individual electrode for each pixel; and a counter substrate facing the matrix substrate with a liquid crystal material interposed therebetween. After forming the individual switch, covering the entire surface of the individual switch with an insulating film, forming a contact hole connected to the individual switch in the insulating film, and forming a concave portion for embedding the individual electrode, A step of depositing a material as a whole, polishing the material of the individual electrode to planarize the same surface as the insulating layer, and alternately forming two types of dielectric films on the planarized individual electrode Forming a dielectric mirror by performing the method. 2. The method according to claim 1, wherein the polishing of the material of the individual electrode is performed by a chemical mechanical polishing method.