JPS6222154B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a method for manufacturing a reflective liquid crystal display device, and particularly to improvement of a display electrode portion serving as a reflective surface.

[Technical background of the invention]

In recent years, there have been remarkable advances in display devices, and display devices using liquid crystals are particularly superior in terms of low power consumption, thinness, and long life, and recently televisions using liquid crystals have also been announced. Currently, liquid crystal televisions use a so-called guest-host type liquid crystal, which uses a nematic liquid crystal mixed with a dichroic dye, for reasons such as low power consumption and a wide viewing angle. In order to obtain high contrast in this guest-host type liquid crystal, it is necessary to make the underlying display electrode a white, bright scattering-reflecting surface. In order to create display electrodes that serve as reflective surfaces, the conventional method is to chemically treat the surface of a white metal such as aluminum to create fine irregularities on the surface, or to create fine irregularities using a similar process. A method has been used in which this is reflected on the display electrodes on the insulating film via the insulating film.

[Problems with background technology]

However, when the display area is large, conventional methods have the disadvantage that not only nonuniformity occurs within the substrate but also variations between lots when chemical processing is performed. There is.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a reflective liquid crystal display device having a display electrode having a bright scattering surface with extremely excellent uniformity.

[Summary of the invention]

In order to make the display electrode of a liquid crystal cell a scattering surface, silicon residue, which can be left with good uniformity and good reproducibility when etching an aluminum film containing silicon, is used as a nucleus for creating unevenness. , a display electrode is provided via an insulating film so as to reflect this unevenness.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a sectional view of one pixel portion for explaining an embodiment in which the present invention is applied to a matrix type liquid crystal display device using a switch/capacitor array, FIG. 2 is an equivalent circuit of the one pixel portion, and FIG. The figure is also an enlarged view of the display electrode portion.

Reference numeral 1 denotes a single crystal silicon substrate (first substrate), on which a switch/capacitor array consisting of a MOSFET 2 and a MOS capacitor 3 is integrated and formed by a silicon gate MOS manufacturing process. 4 is an insulating film deposited by CVD etc.
A hole is made at a predetermined location, and an aluminum film containing silicon is deposited on the hole by sputtering.
Wiring 5 is formed by etching this. When this pattern is formed by etching, silicon residue 6 remains on the surface of the insulating film 4. thus,
On the substrate on which the switch/capacitor array and its wiring are formed, an insulating film 7 is further formed by CVD, etc.
The display electrode 8 is formed by forming apertures thereon and depositing a metal film having a high reflectivity, such as an aluminum film, and patterning this aluminum film. At this time, the insulating film 7 grows with the silicon residue 6 as a nucleus, so as shown in FIG. As a result, the display electrode 8 becomes a good scattering surface. A guest-host type liquid crystal 11 is sandwiched between the substrate on which the switch/capacitor array with display electrodes thus obtained is formed and the glass substrate 10 (second substrate) on which the transparent electrode 9 is formed on the entire surface. , a matrix type liquid crystal display device is constructed.

According to this embodiment, even if the display electrode 8 has a relatively large area, it becomes an extremely uniform bright white scattering surface, and a display with good contrast is possible. Moreover, the uniformity of the scattering surface of the display electrode 8 can be achieved with good reproducibility, and there is little variation between lots.

In the embodiment, the insulating film was deposited by CVD, and the reflective display electrode was made of aluminum, but the material is not limited to these, and any material may be used as long as it satisfies the purpose. Although a single crystal silicon substrate is used as the substrate of the switch/capacitor array, it may also have an SOS structure or a structure in which amorphous silicon or polysilicon is formed on a glass substrate. Further, although a matrix type liquid crystal display device using a switch/capacitor array is shown in the embodiment, the present invention can be similarly applied to other liquid crystal display devices using reflective display electrodes.

〔Effect of the invention〕

According to the present invention, the display electrode surface is made into a white scattering surface with good uniformity and good reproducibility. A method for manufacturing a reflective liquid crystal display device with high contrast can be provided.

[Brief explanation of the drawing]

FIG. 1 is a sectional view for explaining an embodiment of the present invention, FIG. 2 is an equivalent circuit diagram thereof, and FIG. 3 is an enlarged view of the display electrode portion thereof. 1... Single crystal silicon substrate (first substrate), 2
...MOSFET, 3...MOS capacitor, 4...
Insulating film, 5... Wiring (aluminum film containing silicon), 6... Silicon residue, 7... Insulating film, 8
... Display electrode, 9 ... Transparent electrode, 10 ... Glass substrate (second substrate), 11 ... Guest-host type liquid crystal.

Claims (1)

[Claims] 1 A step of forming an aluminum film containing silicon on a first substrate, a step of etching this aluminum film into a predetermined pattern and leaving a silicon residue, and forming an insulating film to reflect the unevenness caused by the silicon residue. a step of forming a reflective display electrode in a predetermined pattern on the insulating film, a step of forming a transparent electrode on the entire surface of a second substrate made of a transparent material, and a step of forming a transparent electrode on the first and second substrates. A method for manufacturing a liquid crystal display device, comprising the step of sandwiching a liquid crystal between the liquid crystal display devices.