KR100556345B1 - A method of manufacturing in-plane switching mode liquid crystal display device - Google Patents

Abstract

According to the method of manufacturing the transverse electric field type liquid crystal display device of the present invention, the bus, the gate wiring and the common electrode are simultaneously etched and patterned in the same double layer with the first mask, and the source / drain electrode and the ohmic contact layer are formed with the second mask. Thereafter, a transverse electric field type liquid crystal display device is manufactured by only three mask processes of successively patterning a gate insulating film, a semiconductor layer, and a protective film with a third mask.

Description

A method of manufacturing a transverse electric field type liquid crystal display device {A METHOD OF MANUFACTURING IN-PLANE SWITCHING MODE LIQUID CRYSTAL DISPLAY DEVICE}

The present invention relates to a method for manufacturing a liquid crystal display device, and more particularly, to a method for manufacturing a transverse electric field type liquid crystal display device using only three mask processes.

In order to solve the disadvantage that the viewing angle of the conventional twisted nematic mode liquid crystal display device is narrow, in recent years, the lateral electric field system solves the viewing angle problem by aligning liquid crystal molecules in a substantially horizontal direction with the substrate. Liquid crystal display devices (in plane switching mode LCD) have been actively studied.

1 (a), (b), (c), (d), and (e) show a manufacturing method of a conventional transverse electric field type liquid crystal display device using five mask processes, in which A-A The line '' represents the cross-sectional area of the extension line of the thin film transistor and the common electrode, and the line 'B-B' represents the cross-sectional area of the extension line of the gate pad and the data pad.

The manufacture of the conventional transverse electric field type liquid crystal display element using five mask processes follows the following process.

First, the bus wiring 103 is deposited on a substrate 101 with a metal such as Al, and then patterned by a photolithography process to form a first gate (FIG. 1A), and then a metal such as Cr or Mo is patterned thereon. The first gate 105 is formed (FIG. 1B). At this time, the common electrode 105a is also formed.

Subsequently, a gate insulating film 107 is formed by coating a material such as SiNx or SiOx on the gate electrode 105 and the common electrode 105a, and then amorphous silicon 109 and impurity amorphous silicon are formed on the gate electrode 105. A semiconductor layer is formed by depositing and patterning (not shown) (FIG. 1C), and a metal such as Cr or Mo is deposited and patterned on the semiconductor layer by a sputtering method to form a source / drain electrode 111 ( 1d). At this time, the data electrode 111a is also formed.

Finally, a material such as SiNx, SiOx, BCB, or acrylic resin is coated on the source / drain electrode 111 and then patterned to form a protective film 113 (FIG. 1E). In this case, a mask is additionally required to form contact holes in the gate and data pad portions after the front deposition of the material.

As described above, the conventional method of manufacturing a transverse electric field type liquid crystal display device which requires five mask processes has a disadvantage in that a large number of defects occur during the process and additional costs are required accordingly.

The present invention is to solve the above problems of the prior art, the gate, gate wiring and common electrodes are simultaneously etched and patterned in the same double layer, the source / drain wiring and the electrode and ohmic contact layer is formed continuously and then the gate insulating film The present invention provides a method of manufacturing a transverse electric field type liquid crystal display device in a shortened process by patterning a semiconductor layer and a protective film.

In order to achieve the above object, a method of manufacturing a transverse electric field liquid crystal display device according to the present invention comprises the steps of forming a bus wiring, a gate wiring and a common electrode by laminating a metal on a first substrate and patterning the first mask; Sequentially depositing inorganic, amorphous silicon, and impurity amorphous silicon over the substrate, depositing a metal on the impurity amorphous silicon layer, and patterning with a second mask to form a source / drain electrode and an ohmic contact layer; and the semiconductor After forming an inorganic or organic protective film on the layer and the source / drain electrode, patterning the gate insulating film, the semiconductor layer and the source / drain electrode with a third mask.

The patterning of the passivation layer using the third mask in the above manufacturing process not only forms the contact hole of the pad region and the passivation layer of the channel portion but also increases the strength of the electric field formed between the common electrode and the data electrode, thereby improving the driving characteristics of the liquid crystal. Improve. In addition, damage to the metal pattern due to stress can be prevented by removing the insulating film in the pad region.

Although not shown in the drawings, the present invention provides a method of coating and orienting a first alignment layer over an entire first substrate, forming a light blocking layer on a second substrate, and a color filter layer on the light blocking layer and the second substrate. Forming a liquid crystal layer; forming a liquid crystal layer between the first substrate and the second substrate; and forming a liquid crystal layer between the first substrate and the second substrate.

Hereinafter, a method of manufacturing a transverse electric field type liquid crystal display device according to the present invention will be described in detail with reference to the accompanying drawings.

2 (a), 2 (b) and 2 (c) show a method of manufacturing a transverse electric field type liquid crystal display device according to the present invention, in which the line A-A 'is a cross section of an extension line of a thin film transistor and a common electrode. The line B-B 'represents a cross-sectional area of the extension line of the gate pad and the data pad.

In the manufacture of the transverse electric field liquid crystal display device according to the present invention, first, by continuously depositing a metal such as Al, Cr or Mo on the first substrate 110, and then simultaneously etching in a state in which the metal layer is blocked with a first mask. The bus wiring 203, the gate 205 and the common electrodes 203a and 205a are formed (FIG. 2A).

In this case, although not shown in the drawing, the gate wiring and the common wiring may be simultaneously formed, and anodization layer may be formed by anodizing the gate electrode and the common electrode to improve insulation.

Thereafter, inorganic materials such as SiOx or SiNx, amorphous silicon (a-Si), and impurity amorphous silicon (n + a-Si) are successively stacked by PECVD (Plasma Enhanced Chemical Vapor Deposition) to form a gate insulating film 207 and a semiconductor layer. 209 and an ohmic contact layer (not shown), a metal such as Cr or Mo is deposited thereon by a sputtering method, blocked with a second mask, and then etched to form a source / drain electrode 211 and data. The electrode 211a and the data wiring 211b are formed, and the ohmic contact layer is patterned using the source / drain electrode 211 as a mask (FIG. 2B).

In this case, an etching stopper layer may be formed on the semiconductor layer 209 of the thin film transistor to prevent the semiconductor layer 209 from being etched when the ohmic contact layer is etched.

Subsequently, an inorganic material such as SiOx, SiNx or the like or an organic material such as benzocyclobutane (BCB) is stacked to form a protective film 213 and then etched in a blocked state with a third mask to etch the protective film 213, the gate insulating film 207, And the amorphous silicon layer 209 is patterned (FIG. 2C).

In this case, as shown in the drawing, the passivation layer 213 forms a passivation layer of the contact hole 215 and the semiconductor layer 209 of the pad region, and only protects the common electrodes 203a and 205a and the data electrode 211a. Remove all that is left.

Subsequently, a first alignment film is applied over the entire substrate. As the alignment layer, an optical alignment material such as polyimide, polyamide-based material or polysiloxanecinnamate, polyvinylcinnamate or cellulosecinnamate is used.

When a polyimide or polyamide-based material is used as the alignment layer, a mechanical method such as rubbing is used to determine the alignment direction of the alignment layer, but light such as polysiloxane, polyvinylcinnamate or cellulose rosincinate is used. In the case of using the alignment material, the alignment direction is determined by irradiating the alignment film with light such as ultraviolet rays.

In particular, since the orientation direction determined by the photoreactive alignment layer varies depending on the inherent properties of the light, such as the polarization direction of the irradiated light, it is possible to solve the problem of dust or static electricity generated in the alignment layer when mechanical rubbing is used. do.

Subsequently, although not shown in the drawings, a black matrix, a color filter layer, and a second alignment layer made of Cr, CrO, or resin, etc. are formed on a substrate facing the substrate, and then liquid crystal is injected between the first substrate and the second substrate. A transverse electric field liquid crystal display device is completed.

According to the present invention, it is possible to shorten the manufacturing process by using three mask processes for simultaneous double gate etching, source / drain etching, and simultaneous etching of the gate insulating film, the semiconductor layer, and the protective film.

In addition, the present invention improves the driving characteristics of the liquid crystal by increasing the strength of the electric field formed between the common electrode and the data electrode by simultaneous etching of the gate insulating film, the semiconductor layer, and the protective film as described above.

Further, damage to the metal pattern due to stress can be prevented due to the removal of the insulating film in the pad region.

1 (a), (b), (c), (d), and (e) show a method of manufacturing a conventional transverse electric field type liquid crystal display device.

2 (a), 2 (b) and 2 (c) are views showing a method of manufacturing a transverse electric field type liquid crystal display device according to the present invention.

* Description of the symbols for the main parts of the drawings *

201: substrate 203: bus wiring

205: gate wiring 205: gate insulating film

209 amorphous silicon layer 211 source / drain electrodes

213: protective shield

Claims (3)

Forming a plurality of metal layers on the transparent substrate and selectively etching the metal layers using a first mask to simultaneously form a gate electrode and a common electrode; A gate insulating film, a semiconductor layer, and an impurity amorphous silicon layer are successively stacked on the entire surface of the transparent substrate including the gate electrode and the common electrode, and the metal is deposited on the impurity amorphous silicon layer and used as a second mask. Selectively etching the impurity amorphous silicon layer to form a source / drain electrode and a data electrode and an ohmic contact layer; And forming a protective film on the transparent substrate and selectively patterning the protective film, the gate insulating film, the semiconductor layer, and the source / drain electrodes using a third mask. The method of claim 1, wherein the ohmic contact layer is patterned using the source / drain electrodes as a mask. The method of manufacturing a transverse electric field liquid crystal display device according to claim 1, wherein the material constituting the gate insulating film and the protective film is selected from the group consisting of SiOx and SiNx.