Apparatus and method of fabricating flat plate display

A fabricating apparatus and a method of a flat plate display are disclosed. A fabricating apparatus of a flat plate display includes a stage on which a substrate is seated, an imprinting mold bonded with the substrate to form a thin film pattern on the substrate, the imprinting mold comprises projections and grooves, a supporter configured to support the imprinting mold, and a horizontal compensating part configured to compensate downward-bending of the imprinting mold by pressing the imprinting mold.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of the Patent Korean Application No, 10-2009-0127030, filed on Dec. 18, 2009, which is hereby incorporated by reference as if fully set forth herein.

BACKGROUND OF THE DISCLOSURE

1. Field of the Disclosure

The present invention relates to a fabricating apparatus and method of a flat plate display which can reduce bending-down of an imprinting mold.

2. Discussion of the Related Art

Various kinds of flat plate displays capable of reducing a weight and volume which are disadvantages of a cathode ray tube (CRT) haven been emerging recently. Such a flat plate display includes a liquid crystal display (LCD), a field emission display, a plasma display panel and an electro-luminescence (EL) display.

This flat plate display is configured of a plurality of thin films formed by a mask process including depositing (coating), exposing, developing and etching. However, the mask process has complicated fabricating assembly process and it has a disadvantage of high production cost. As a result, research and study haven been under progress to form thin films via a patterning process using an imprinting mold in recent.

According to this patterning process, when a liquid polymeric precursor contacts with a imprinting mold which has a groove and a projection after liquid resin is painted on a substrate, the groove and the projection of the imprinting mold are reverse-transferred to the liquid polymeric precursor and the reverse-transferred liquid polymeric precursor is hardened in a hardening process to form a desired thin film pattern on the substrate.

Here, a related art imprinting mold10is supported by supporters20as shown inFIG. 1. However, the supporters20support only edges of the imprinting mold. Because of that, a back plate of the imprinting mold would bend downward only to come down by 1 mm or less.

In this case, when separating the imprinting mold and the substrate from each other, the bending back plane of the imprinting mold might be straightened and this would generate elasticity damaging to the imprinting mold10disadvantageously. In addition, if the bending degree of the imprinting mold10is large, the imprinting mold10and the substrate has to maintain a gap larger than the bending-down when the imprinting mold10and the substrate are aligned. Because of that, a vertical motion width of a stage having the substrate seated thereon will be getting large after the alignment process until a bonding process between the imprinting mold and the substrate and an error will be getting large accordingly.

Furthermore, the bending imprinting mold10is straightened as bonded with the substrate, after the imprinting mold10in a state of bending and the substrate are aligned. Because of that, an error of alignment accuracy might be generated.

SUMMARY OF THE DISCLOSURE

Accordingly, the present invention is directed to a fabricating apparatus and method of a flat plate display

An object of the present invention is to provide a fabricating apparatus of a flat plate display which is able to reduce bending-down of an imprinting mold.

To achieve these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, a fabricating apparatus of a flat plate display includes a stage on which a substrate is seated; an imprinting mold bonded with the substrate to form a thin film pattern on the substrate, the imprinting mold comprises projections and grooves; a supporter configured to support the imprinting mold; and a horizontal compensating part configured to compensate downward-bending of the imprinting mold by pressing the imprinting mold.

The size of the imprinting mold may be larger than the size of the substrate and the supporter and the horizontal compensating part may be installed an edge of the imprinting mold which is not overlapped with the substrate.

The horizontal compensating part may be not in contact with the imprinting mold when the imprinting mold and the substrate are bonded with each other and the horizontal compensating part may be in contact with the imprinting mold when the imprinting mold and the substrate are separated from each other.

The fabricating apparatus may further include a supporting frame configured to support the horizontal compensating part and the supporter, wherein the horizontal compensating part moves upward and downward along a moving passage of the supporting frame.

The horizontal compensating part may be formed of Sus or Aluminum based material.

In another aspect of the present invention, a fabricating method of a flat plate display includes steps of: seating a substrate having liquid polymeric precursor formed thereon on a stage; bonding an imprinting mold and the substrate with each other by moving the stage upward, for grooves and projections of the imprinting mold to press the liquid polymeric precursor; and separating the imprinting mold and the substrate from each other by allowing a supporter to support the imprinting mold and allowing a horizontal compensating part to press the imprinting mold in an opposite direction with respect to the supporter simultaneously with moving the stage downward.

The horizontal compensating part may move in opposite direction with respect to the imprinting mold along a moving passage of a supporting frame configured to support the horizontal compensating part when the imprinting mold and the substrate are bonded with each other, and the horizontal compensating part may move in direction with respect to the imprinting mold along the moving passage of the supporting frame when the imprinting mold and the substrate are separated from each other.

The present invention may have following advantages.

The fabricating apparatus and method of the flat plate display may reduce bending-down of the imprinting mold by using the horizontal compensating part capable of compensating the load of the imprinting mold. Moreover, the fabricating apparatus and method may fix the imprinting mold without bending-down of the imprinting mold, when the imprinting mold and the substrate are separated from each other. As a result, damage to the imprinting mold and the thin film pattern may be prevented.

DESCRIPTION OF SPECIFIC EMBODIMENTS

FIG. 2is a sectional view illustrating a fabricating apparatus of a flat plate display according to the present invention.

The fabricating apparatus for imprinting includes a substrate101, an imprinting mold110, a light source part112, a vision part124and a mold-for-imprinting support part120.

The substrate is vacuum-absorbed to a stage102and it is seated on the stage102. On such the substrate101may be formed a thin film pattern104configured of liquid polymeric precursor patterned by pressing-contact with the imprinting mold110. The thin film pattern104has a predetermined shape reverse-transferred from grooves and projections of the imprinting mold110.

The imprinting mold110includes a back plane108and a mold part106formed on the back plane108. The size of the back plane108may be formed larger than the size of the substrate101as shown inFIG. 3. The size of the mold part106may be formed similar to the size of the substrate and it includes grooves and projections to form the thin film pattern104.

The light source part112emits lights such as ultraviolet rays or infrared rays to the imprinting mold110to harden the thin film pattern104formed on the substrate101.

The vision part124identifies a location difference between the imprinting mold110and the substrate101and it compensate the difference.

The mold-for-imprinting support part120includes a supporting frame114, a supporter116and a horizontal compensating part118as shown inFIG. 4.

The supporting frame114supports the supporter116and the horizontal compensating part118and it forms a vertical motion passage of the horizontal compensating part118.

The supporter116is formed to allow an edge of a back surface of the back plane108of the imprinting mold110seated thereon. That is, the supporter116contacts with the edge of the back surface of the imprinting mold110. As a result, the supporter116may not affect the moving passage of the ultraviolet rays or infrared rays when the liquid polymeric precursor is hardened by using the light source part112.

The horizontal compensating part118contacts with an edge of a top surface of the back plane108of the imprinting mold110which is not overlapped with the substrate as shown inFIG. 2. Also, the horizontal compensating part118is formed of hard heavy material, for example, Stainless steel, Al, and the like and the area of the horizontal compensating part118may be minimized as possible accordingly. Because of that, the horizontal compensating part118may not affect the moving passage of the ultraviolet rays and infrared rays when the light source part112hardens the liquid polymeric precursor.

When the imprinting mold110is bonded with the substrate101, the horizontal compensating part118may move upward along the vertical moving passage of the supporting frame114and it may not contact with the top surface of the imprinting mold110accordingly. As a result, the pressure applied by the load of the horizontal compensating part118may not be applied to the liquid polymeric precursor formed on the substrate101when the imprinting mold110is bonded with the substrate101.

Also, the horizontal compensating parts118may be arranged alternatively with respect to the supporters116. For example, the horizontal compensating part118may be formed more distant from the mold part106of the imprinting mold110than the support116.

Such the horizontal compensating part118compensates the load of the back plane108to prevent the imprinting mold110from moving downward because of the load of the back plane108seated on the supporters116. that is, the horizontal compensating parts118applies a predetermined pressure to an outer edge of the top surface of the back plane108in a predetermined direction parallel to the downward moving direction of the back plane108.

FIG. 5is a diagram illustrating the degree of the bending-down of the imprinting mold according to the present invention

As shown inFIG. 5, the related art imprinting mold will bend toward the substrate along a direction to a center from an outer portion thereof. Especially, the maximum distance of the bending-down of the related art imprinting mold is approximately 847 μm toward the substrate as shown inFIG. 5and Table 1.

In contrast, the imprinting mold110according to the present invention may have the minimum bending-down because of the horizontal compensating part118. especially, the downward-bending of the imprinting mold110according to the present invention may be reduced approximately by 120 μm less than the downward-bending of the related art imprinting mold, as shown in Table 1.

As mentioned above, the fabricating apparatus of the flat plate display according to the present invention may reduce the downward-bending of the imprinting mold110generated by the load of the back plane108by using the horizontal compensating part118capable of compensating the load of the imprinting mold110. In addition, the fabricating apparatus according to the present invention may fix the imprinting mold110without the downward-bending, when the imprinting mold110and the substrate101are separated from each other. As a result, damage to the imprinting mold110and the thin film pattern may be prevented.

FIGS. 6A to 6Care sectional views illustrating a fabricating method of a flat plate display which uses the fabricating apparatus shown inFIG. 2.

First of all, the liquid polymeric precursor126is coated, for example, spin-coated, spinless-coated and the like on the substrate101. The substrate101having the liquid polymeric precursor126is seated on the stage102as shown inFIG. 6A. The stage102having the substrate101seated thereon moves upward by the maximum height not in contact with the imprinting mold110. After that, the imprinting mold110and the substrate101are aligned to for align-keys (not shown) formed in both the imprinting mold110and the substrate101via the vision part124to correspond with each other.

The stage102having the substrate aligned to the imprinting mold thereon may move upward higher than the height of the supporter116as shown inFIG. 6B. At the same time, the horizontal compensating part118may move upward toward the vision part124along the passage of the supporting frame114to make the imprinting mold110not contact with the horizontal compensating part118.

Here, when the stage102moves upward higher than the height of the supporter116, the imprinting mold110is bonded with the substrate101. After that, solvent in the liquid polymeric precursor is absorbed to a surface of the imprinting mold110to move the liquid polymeric precursor into the grooves of the imprinting mold110and the liquid polymeric precursor is hardened by the light source part112to form the thin pattern104on the substrate101. The thin film pattern104has a shape reverse-transferred from the grooves of the imprinting mold110.

Hence, as shown inFIG. 6C, the stage102on which the substrate101having the thin film pattern104formed therein is seated may move downward and the horizontal compensating part118may move downward toward the imprinting mold110simultaneously. As a result, the imprinting mold110is horizontally fixed by the horizontal compensating parts118and the supporters116and the substrate101having the thin film pattern104formed thereon is separated from the imprinting mold110

The thin film pattern104formed by using the imprinting mold110is applicable to a liquid crystal display panel shown inFIG. 7. specifically, the liquid crystal display panel according to the present invention shown inFIG. 7includes a thin film transistor substrates150and a color filter substrate140which are bonded in opposite, with a liquid crystal layer160formed there between.

The color filter substrate140includes a black matrix144formed on an upper substrate142to prevent light escape, a color filter166configured to represent colors, a common electrode148configured to form a pixel electrode and an electric field, a cover-coat layer configured for planarization, a column spacer formed on the over-coat layer to maintain a cell gap and an upper alignment layer (not shown) configured to cover the other components.

The thin film transistor substrate150includes gate lines156and data lines164which are formed on a lower substrate152with crossing each other, thin film transistors168located adjacent to cross points of the gate and data lines, pixel electrodes170formed in pixel regions formed by the cross-over structure, and a lower alignment layer (not shown) configured to cover the other components.

Such the color filter166, black matrix154, column spacer, thin film transistors168, gate lines156and data lines164and pixel electrode170may be formed by the patterning process using the above imprinting mold including the grooves corresponding to patterns thereof.