KR20080039629A - Method of manufacturing plastic substrate for display panel - Google Patents

Abstract

A method for fabricating a plastic substrate for a liquid crystal panel is provided to reduce repair costs because the plastic substrate has a low heat expansion coefficient, removing the problem of controlling alignment between the plastic substrate and layers of a TFT(Thin Film Transistor) array and a color filter array. A glass substrate(50) is provided. A detachment protection layer(60) is formed on the glass substrate. An adhesion accelerating layer(70) is formed on the detachment protection layer. A plastic substrate(100) is formed on the adhesion accelerating layer. An array is formed on the plastic substrate. The glass substrate, the detachment protection layer and the adhesion accelerating layer are detached from the array-formed plastic substrate. In forming the array on the plastic substrate, a color filter array and a TFT array are formed on the plastic substrate. In forming the plastic substrate on the adhesion accelerating layer, a hard coating layer is formed on the plastic substrate.

Description

The manufacturing method of the plastic substrate for liquid crystal display panels {METHOD OF MANUFACTURING PLASTIC SUBSTRATE FOR DISPLAY PANEL}

1 is a cross-sectional view illustrating a liquid crystal display panel according to a first embodiment of the present invention.

2A and 2F are cross-sectional views illustrating a manufacturing process of a plastic substrate on which the thin film transistor array shown in FIG. 1 is formed.

3 is a cross-sectional view illustrating a liquid crystal display panel according to a second exemplary embodiment of the present invention.

<Short description of drawing symbols>

50: glass substrate 60: removable protective layer

70 adhesion bonding layer 100 first plastic substrate

110: hard coating layer 150: gate insulating film

130: thin film transistor 140: semiconductor pattern

150: data line 160: protective film

165: pixel electrode 167: hole

180: thin film transistor substrate 180: liquid crystal

200: second plastic substrate 210: black matrix

220: color filter 230: common electrode

240: color filter substrate 300: liquid crystal display panel

The present invention relates to a method for manufacturing a plastic substrate for a liquid crystal display panel, and more particularly to a method for manufacturing a plastic substrate for a liquid crystal display panel that can solve the problem of alignment adjustment between the plastic substrate and the layer of the color filter array and the thin film transistor array.

Liquid crystal displays (LCDs) are representative of flat panel displays, and have advantages such as small size, light weight, and low power consumption compared to cathode ray tubes. Therefore, the liquid crystal display device is widely applied to the general industry, for example, the computer industry, the electronic industry, the information and communication industry, etc. due to such unique advantages. Such a liquid crystal display device displays a desired image by applying an electric field to a liquid crystal material having an anisotropic dielectric constant injected between a color filter substrate and a thin film transistor substrate, and controlling the amount of light transmitted through the substrate by adjusting the intensity of the electric field. .

In order to meet the needs of users, liquid crystal displays are progressing in the direction of large screen, high definition, high resolution, high display speed, and low power consumption. At the same time, liquid crystal display devices have been developed with flexibility by requiring users to be convenient to carry. Such a liquid crystal display device fabricates a liquid crystal display panel on a plastic substrate rather than a conventional glass substrate. In addition, the liquid crystal display panel made of a plastic substrate can be manufactured by vapor deposition or printing in terms of the process of the liquid crystal display panel made of a glass substrate, and thus manufacturing cost is low. In addition, since the liquid crystal display panel made of a plastic substrate is cheaper than the glass substrate and does not break during manufacturing, the impact resistance may be increased.

A glass carrier is formed under the plastic substrate. The plastic substrate and the glass carrier are bonded to each other with an adhesive tape. This is because the thin film transistor array and the color filter array are formed on the plastic substrate. However, the plastic substrate applied to the liquid crystal display has a high coefficient of thermal expansion, which causes the plastic substrate to expand / contract, thereby making it very difficult to adjust alignment between the plastic substrate, the thin film transistor array, and the layers of the color filter array.

Therefore, the technical problem to be achieved by the present invention is to form a plastic substrate by dissolving the plastic, which is a plastic substrate for the liquid crystal display panel that can solve the alignment control problem between the plastic substrate and the layer of the color filter array and thin film transistor array It is to provide a method for producing.

In order to achieve the above technical problem, a method of manufacturing a plastic substrate for a liquid crystal display panel of the present invention comprises the steps of providing a glass substrate; Forming a detachable protective layer on the glass substrate; Forming an adhesion promoter layer on the detachable protective layer; Forming a plastic substrate on the adhesion promotion layer; Forming an array on the plastic substrate; And detaching a glass substrate, the detachment protection layer, and the adhesion promotion layer from the plastic substrate on which the array is formed.

The forming of the array on the plastic substrate may include forming a color filter array on the plastic substrate.

In addition, the forming of the array on the plastic substrate may include forming a thin film transistor array on the plastic substrate.

On the other hand, the step of forming a plastic substrate on the adhesion promoter layer is characterized in that it further comprises the step of forming a hard coating layer on the plastic substrate.

The hard coating layer is characterized in that formed of acrylic or urethane.

The plastic substrate may be formed of any one of polyimide, polyether sulfone, polycarbonate, polyarylide, polyethylene naphthalate and polyethylene terephthalate.

The forming of the plastic substrate on the adhesion promoting layer is characterized in that the plastic is dissolved and coated.

In addition, the detachable protective layer may be formed of an inorganic insulating film or an organic insulating film.

In addition, the adhesion promoting layer is characterized in that formed of siloxane.

Other technical problems and advantages of the present invention in addition to the above technical problem will be apparent from the description of the preferred embodiment of the present invention with reference to the accompanying drawings.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to FIGS. 1 to 3.

1 is a cross-sectional view illustrating a liquid crystal display panel according to a first embodiment of the present invention.

Referring to FIG. 1, the liquid crystal display panel 300 according to an exemplary embodiment of the present invention includes the first and second plastic substrates 100 and 200 and the liquid crystal 190 having an array. A thin film transistor array is formed on the first plastic substrate 100 to form the thin film transistor substrate 180, and a color filter array is formed on the second plastic substrate 200 to form the color filter substrate 240.

The thin film transistor substrate 180 includes a first plastic substrate 100, a gate line (not shown) and a data line 150 formed between the gate insulating layer 140, the thin film transistor 130, and a pixel electrode. (165).

The first plastic substrate 100 is formed of a material such as transparent polyimide (PI), which is hardened as the manufacturing process of the plastic substrate proceeds, thereby causing resistance to chemical reactions.

The gate line is formed on the first plastic substrate 100. The gate line is connected to the gate electrode 131 of the thin film transistor 130 to supply a gate signal to the gate electrode 131 of the thin film transistor 130.

In the data line 150, the thin film transistor 130 supplies the pixel voltage signal to the source electrode 133. The data line 150 is formed to cross the gate line with the gate insulating layer 120 therebetween to define the pixel area.

The gate insulating layer 120 is formed between the gate electrode 131, the source electrode 133, and the drain electrode 135 to insulate them. In addition, the gate line and the data line 150 cross each other with the gate insulating layer 120 interposed therebetween to define each sub pixel area.

The thin film transistor 130 causes the pixel signal supplied to the data line 150 to be charged to the pixel electrode 165 in response to the scan signal supplied to the gate line. To this end, the thin film transistor 130 is connected to the pixel electrode 165 facing the gate electrode 131 connected to the gate line, the source electrode 133 connected to the data line 150, and the source electrode 133. A drain electrode 135 is provided. In addition, the thin film transistor 130 includes a semiconductor pattern 140 that forms a channel between the source electrode 133 and the drain electrode 135 while overlapping the gate electrode 131 and the gate insulating layer 120 therebetween. .

The semiconductor pattern 140 includes an active layer 141 formed to form a channel between the source electrode 133 and the drain electrode 135 and overlap the gate electrode 131 with the gate insulating layer 120 therebetween. The semiconductor pattern 140 is formed on the active layer 141 and further includes an ohmic contact layer 143 for ohmic contact with the data line 150, the source electrode 133, and the drain electrode 135.

The pixel electrode 165 is formed on the passivation layer 160 covering the thin film transistor 130 and is connected to the drain electrode 135 exposed through the contact hole 165 penetrating the passivation layer 160. When the image data signal from the thin film transistor 130 is supplied, the pixel electrode 165 drives the liquid crystal 190 with a voltage difference from the common electrode 230 of the color filter substrate 240 to adjust the light transmittance.

The liquid crystal 190 is rotated by the difference between the common voltage from the common electrode 230 of the color filter substrate 240 and the pixel voltage from the pixel electrode 165 of the thin film transistor substrate 180 to adjust the light transmittance. To this end, the liquid crystal 190 is made of a material having dielectric anisotropy and refractive index anisotropy.

The color filter substrate 240 is formed of the second plastic substrate 200, the black matrix 210, the color filter 220, and the common electrode 230.

The second plastic substrate 200 is formed of a material such as transparent PI that is cured as the manufacturing process of the plastic substrate proceeds, thereby causing resistance to chemical reactions.

The black matrix 210 is formed in a matrix form on the second plastic substrate 200 to distinguish the pixel region in which the color filter 220 is to be formed, and the gate line 160 and the data line of the thin film transistor substrate 180 ( 150, and overlapping with the thin film transistor 130. The black matrix 210 blocks the light generated by the undesired arrangement of the liquid crystal 190 to improve the contrast of the liquid crystal display panel 300 and to block the direct light irradiation to the thin film transistor 130 to prevent the thin film transistor. The photo leakage current of 130 is prevented.

The color filter 220 includes red (R), green (G), and blue (B) color filters 220 to implement an image. The red (R), green (G), and blue (B) color filters 220 respectively absorb light of a specific wavelength through their included red (R), green (G), and blue (B) pigments. By transmitting, red (R), green (G), and blue (B) are displayed. In this case, various colors are realized through additive mixing of red (R), green (G), and blue (B) light transmitted through the red (R), green (G), and blue (B) color filters 220, respectively. The color arrangement of the color filter 220 has a stripe shape in which red (R), green (G), and blue (B) color filters 220 are arranged in a line.

The common electrode 230 is formed to correspond to the pixel voltage of the pixel electrode 165 formed on the thin film transistor substrate 180, and controls the light transmittance by driving the liquid crystal 190 with a voltage difference from the pixel electrode 165. In addition, the common electrode 230 is formed of a transparent and conductive material such as indium tin oxide (ITO), tin oxide (TO), indium zinc oxide (IZO), or indium tin zinc oxide (ITZO). The common electrode 230 is formed to cover the black matrix 210 and the color filter 220.

2A and 2F are cross-sectional views illustrating a manufacturing process of a plastic substrate on which the thin film transistor array shown in FIG. 1 is formed.

Referring to FIG. 2A, a glass substrate 50 is prepared to form the thin film transistor substrate 180. Such a glass substrate 50 is preferably used that is excellent in sensitivity characteristics and not easily bent.

Referring to FIG. 2B, a detachable protective layer 60 is formed on the glass substrate 50. Specifically, in the case of the desorption protection layer 60 made of oxides such as silicon oxide (SiOx) and gallium oxide (GaOx), which are inorganic insulating films, the desorption protection layer 60 is formed on the glass substrate 50 by using a sputtering method. To be deposited on. In the case of a desorption protective layer 60 made of a-Si or the like, the desorption protective layer 60 is deposited on the glass substrate 50 by a chemical vapor deposition (CVD) method. In addition, when the desorption protective layer 60 is an organic insulating film, it is deposited through a coating process such as spin coating.

Referring to FIG. 2C, an adhesion promoting layer 70 is formed on the detachable protective layer 60. Specifically, the adhesion promotion layer 70 is preferably formed of a siloxane compound. Coating by spin coating or the like, spin drying or heating at 80 to 120 ° C., followed by drying to form an adhesion promotion layer 70 on the desorption protective layer 60.

Referring to FIG. 2D, the first plastic substrate 100 is formed on the adhesion promoting layer 70. Specifically, the first plastic substrate 100 is formed of a material such as transparent PI that is cured as the manufacturing process of the plastic substrate proceeds, thereby causing resistance to chemical reactions. The plastic is dissolved to form a solution, coated, and dried to form the first plastic substrate 100 on the adhesion promoter layer 70.

Referring to FIG. 2E, a thin film transistor array is formed on the first plastic substrate 100. The application temperature of the thin film transistor array manufacturing process varies depending on the type of plastic. Therefore, in the case of transparent PI it is possible to process at 300 ℃ or more.

Referring to FIG. 2F, when a thin film transistor array is formed, a desorption process is performed. The desorption process is performed using a laser when the desorption protective layer 60 is an inorganic insulating film or is dissolved in a compound such as Dimethyformamide (DMF) or Dichloromethane when the desorption protection layer 60 is an organic insulating film. Therefore, the glass substrate 50, the detachable protective layer 60, and the adhesion promoting layer 70 are detached from the first plastic substrate 100.

The manufacturing method of the second plastic substrate 200 in which the color filter array is formed is also the same as the manufacturing method of the first plastic substrate 100 in which the thin film transistor array is formed.

3 is a cross-sectional view illustrating a liquid crystal display panel according to a second exemplary embodiment of the present invention.

3, the hard coating layer 110 is formed on the first and second plastic substrates 100 and 200 in contrast to the liquid crystal display panel 300 illustrated in FIG. 1. And the same components. Accordingly, detailed description of the same components will be omitted. 2A to 2F, the same manufacturing method is omitted except that the hard coating layer 110 is formed on the first and second plastics.

The first and second plastic substrates 100 and 200 may be made of polyether sulfone (PolyEhterSulfone: PES), polycarbonate (PC), polyarylate (PAR), and polyethylene naphthalate (PolyEylene). Naphthalate (hereinafter referred to as PEN) and Polyethylene Terephthalate (hereinafter referred to as PET). The first and second plastic substrates 100 and 200 are preferably formed of PES, PC, PAR, or the like.

During the process of forming the thin film transistor array and the color filter array on the first and second plastic substrates 100 and 200, a problem occurs in that PES, PC, and PAR are dissolved, resulting in the first and second plastic substrates 100 and 200. The hard coating layer 110 is formed on the. The hard coating layer 110 is preferably formed of acrylic or urethane. The hard coating layer 110 is formed by forming the first and second plastic substrates 100 and 200 and coating the acrylic and urethane based on the first and second plastic substrates 100 and 200.

The process of forming the thin film transistor array and the color filter array on the first and second plastic substrates 100 and 200 depends on the type of plastic. PES and PC can form thin film transistor array and color filter array at temperatures of 200 ~ 220 ℃. In addition, the PAR may form a thin film transistor array and a color filter array at a temperature of 300 ° C. or higher.

In this way, by dissolving plastic to form a solution to form the first and second plastic substrates 100 and 200, alignment control between the first and second plastic substrates 100 and 200 and the array of the thin film transistor array and the color filter array may be controlled. The manufacturing process is easy and the problem that a defect occurs can be solved easily.

As described above, the method for manufacturing a plastic substrate for a liquid crystal display panel according to the present invention uses a glass substrate, a detachable protective layer, and an adhesion promoting layer to produce a plastic substrate by dissolving and coating plastic. Accordingly, the plastic substrate thus manufactured has a low coefficient of thermal expansion, thereby eliminating the problem of alignment control between the plastic substrate, the thin film transistor array, and the layers of the color filter array, thereby facilitating the manufacturing process. In addition, the plastic substrate thus produced can be seen that the repair cost is reduced because a lot of defects are eliminated.

In the detailed description of the present invention described above with reference to the preferred embodiment of the present invention, those skilled in the art or those skilled in the art having ordinary knowledge of the present invention described in the claims to be described later It is apparent that various modifications and changes can be made in the present invention without departing from the spirit and scope of the invention.

Claims (9)

Providing a glass substrate; Forming a detachable protective layer on the glass substrate; Forming an adhesion promoter layer on the detachable protective layer; Forming a plastic substrate on the adhesion promotion layer; Forming an array on the plastic substrate; And detaching a glass substrate, the detachable protective layer, and the adhesion promoting layer from the plastic substrate on which the array is formed. The method of claim 1, Forming an array on the plastic substrate Forming a color filter array on the plastic substrate, characterized in that it comprises a plastic substrate for a liquid crystal display panel. The method of claim 1, Forming an array on the plastic substrate And forming a thin film transistor array on the plastic substrate. The method of claim 2 or 3, Forming a plastic substrate on the adhesion promoter layer The method of manufacturing a plastic substrate for a liquid crystal display panel further comprising the step of forming a hard coating layer on the plastic substrate. The method of claim 4, wherein The hard coating layer is a method of manufacturing a plastic substrate for a liquid crystal display panel, characterized in that formed of acrylic or urethane. The method of claim 5, The plastic substrate is formed of a transparent polyimide, polyether sulfone, polycarbonate and polyarylade, and plastics of any one of polyethylene naphthalate and polyethylene terephthalate. . The method of claim 6, Forming a plastic substrate on the adhesion promoter layer Dissolving and coating the said plastic, The manufacturing method of the plastic substrate for liquid crystal display panels characterized by the above-mentioned. The method of claim 7, wherein The desorption protective layer is a method of manufacturing a plastic substrate for a liquid crystal display panel, characterized in that formed of an inorganic insulating film or an organic insulating film. The method of claim 8, The adhesion promotion layer is formed of a siloxane-based method of manufacturing a plastic substrate for a liquid crystal display panel.

Images