KR101386563B1 - Method for fabricating flexible display device - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a flexible display device. The flexible display device includes: a gate electrode, a storage electrode, and a gate pad formed on a sus substrate; A first insulating layer formed on the gate electrode, the storage electrode and the gate pad; A semiconductor layer formed on the first insulating film on the gate electrode; A source electrode, a drain electrode, and a data pad formed on the first insulating layer including the semiconductor layer; A second insulating layer formed on the entire substrate and having a plurality of contact portions respectively exposing the drain electrode, the storage electrode and the data pad, and a part of the sus substrate; And a pixel electrode formed on the second insulating layer and electrically connected to the drain electrode, the storage electrode and the data pad, and a sus substrate through the plurality of contact parts, respectively. It is configured to include.

Sus board, gate pad, data pad, board contact

Description

Flexible display device manufacturing method {METHOD FOR FABRICATING FLEXIBLE DISPLAY DEVICE}

1 is a cross-sectional view illustrating a flexible display device according to an exemplary embodiment of the prior art.

2 is a cross-sectional view illustrating a flexible display device according to another exemplary embodiment of the prior art.

3 is a cross-sectional view illustrating a flexible display device according to the present invention.

4A to 4F are cross-sectional views illustrating a flexible display device according to the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS -

101: lower substrate 103: buffer layer 105: gate electrode 107: storage electrode

109: gate pad 111: first insulating film

113: active layer pattern 115: source electrode

117: drain electrode 119: data pad

121: protective film 123: second insulating film

125a: first contact portion 125b: second contact portion

125c: third contact portion 125d: fourth contact portion

127: pixel electrode 129: gate pad electrode

131: data pad electrode 133: substrate contact electrode

The present invention relates to a method of manufacturing a flexible display device, and more particularly, a phenomenon in which an image becomes dark or a contrast ratio is lowered due to charge charging between a flexible substrate and an upper electrode. A method of manufacturing a flexible display device.

In today's information society, display is more important as a visual information transmission medium, and in order to preoccupy a major position in the future, it is necessary to satisfy requirements such as low power consumption, thinness, light weight, and high definition.

The display itself is a cathode ray tube (CRT), an electroluminescent element (EL), a light emitting diode (LED), a vacuum fluorescence display (VFD), an electric field It can be divided into emission type such as field emission display (FED), plasma display panel (PDP), and non-emission type such as liquid crystal display (LCD). .

Meanwhile, it is predicted that a flexible display that will not be damaged even when the display device is folded or rolled up will emerge as a new technology in the display field.

Currently, there are various obstacles to the implementation of flexible displays, but with the development of technology, thin film transistor liquid crystal display, organic light emitting diodes (OLED) and electrophoretic technologies will become mainstream.

In order to implement a flexible display using the liquid crystal display and the organic EL, a flexible substrate such as a plastic substrate must be used.

In this regard, the flexible display manufacturing method according to the related art will be described with reference to FIG. 1 as follows.

1 is a cross-sectional view illustrating a flexible display device according to an exemplary embodiment of the prior art.

Referring to FIG. 1, in the flexible display device according to the related art, a TFT is formed by depositing an overcoat layer 13 on a glass substrate 11 and then depositing a conductive material layer thereon, and then selectively patterning the conductive material layer. The gate electrode 15 and the storage electrode 17 are formed in the channel portion and the storage portion, respectively. In this case, a gate pad (not shown) is also formed when the gate electrode 15 is formed.

Next, a first insulating layer 19 and a semiconductor layer (not shown) are sequentially deposited on the entire substrate including the gate electrode 15 and the storage electrode 17.

Subsequently, the semiconductor layer (not shown) is selectively patterned to form a semiconductor layer pattern 21 on the gate electrode 15.

Next, a conductive material layer is deposited on the first insulating layer 19 including the semiconductor layer pattern 21 and then selectively patterned to form a source electrode 23 and a drain electrode spaced apart from each other by a predetermined distance, that is, a channel length. 25). In this case, a data pad (not shown) is also formed when the source electrode 23 and the drain electrode 25 are formed. In this case, the drain electrode 25 also overlaps the storage electrode 17. Therefore, part of the drain electrode 25 is also used as the upper electrode of the capacitor.

Subsequently, a thick interlayer insulating film 27, which is a second insulating film, is deposited on the entire substrate including the source electrode 23 and the drain electrode 25, and then a protective layer 29 is deposited on the interlayer insulating film 27.

Next, the protective layer 29 and the interlayer insulating layer 27 are selectively patterned to form a drain contact hole 31 exposing a part of the drain electrode 25.

Subsequently, a transparent material such as ITO is deposited on the protective layer 29 including the drain contact hole 31 and then selectively patterned to form a pixel electrode 33 electrically connected to the drain electrode 25. do.

However, according to one embodiment of the prior art, when an E-book TFT is fabricated on the glass substrate 11, no charge is charged between the glass substrate 11 and the TFT because of the insulating property of the glass. That is, the parasitic capacitor is generated between the storage electrode 17 of the capacitor and the upper electrode which is a part of the drain electrode 25 and between the upper electrode and the pixel electrode 33, but the storage electrode of the glass substrate 11 and the capacitor. It is not generated between (17).

Meanwhile, a flexible display device according to another embodiment of the related art proposed to solve this problem will be described with reference to FIG. 2.

2 is a cross-sectional view illustrating a flexible display device according to another exemplary embodiment of the prior art.

Referring to FIG. 2, in the flexible display device according to the related art, an overcoat layer 53 is deposited on a sus substrate 51 instead of glass, and then a conductive material layer is deposited thereon, followed by the conductive material layer. Is selectively patterned to form a gate electrode 55 and a storage electrode 57 in the TFT channel portion and the storage portion, respectively. In this case, a gate pad (not shown) is also formed when the gate electrode 55 is formed.

Next, a first insulating layer 59 and a semiconductor layer (not shown) are sequentially deposited on the entire substrate including the gate electrode 55 and the storage electrode 57.

Subsequently, the semiconductor layer (not shown) is selectively patterned to form a semiconductor layer pattern 61 on the gate electrode 55.

Next, a conductive material layer is deposited on the first insulating layer 59 including the semiconductor layer pattern 61 and then selectively patterned to form a source electrode 63 and a drain electrode spaced apart from each other by a predetermined distance, that is, a channel length. 65). In this case, a data pad (not shown) is also formed when the source electrode 63 and the drain electrode 65 are formed. At this time, the drain electrode 65 also overlaps the upper side of the storage electrode 57. Therefore, part of the drain electrode 65 is also used as the upper electrode of the capacitor.

Subsequently, a thick insulating interlayer 67 is deposited on the entire substrate including the source electrode 63 and the drain electrode 65, and then a protective layer 69 is deposited on the interlayer insulating layer 67.

Next, the protective layer 69 and the interlayer insulating layer 67 are selectively patterned to form a drain contact hole 31 exposing a part of the drain electrode 65.

Subsequently, a transparent material such as ITO is deposited on the protective layer 69 including the drain contact hole 71 and then selectively patterned to form a pixel electrode 73 electrically connected to the drain electrode 65. do.

However, according to another embodiment of the prior art, unlike the embodiment of the prior art, when manufacturing the E-book TFT on the sus substrate 51, the sus substrate 51 and the sus substrate due to the conductivity of the sus (sus). The charge is charged between the TFTs. That is, parasitics between the storage electrode 57 of the capacitor and the upper electrode which is part of the drain electrode 65, between the upper electrode and the pixel electrode 73, and between the sus substrate 51 and the storage electrode 57 of the capacitor. The capacitor is created.

Due to the conductivity of the substrate, electric charges are charged between the electrode and the substrate, and the sus substrate is electrically disconnected and is floating.

Therefore, the voltage of the upper storage electrode is not constant due to the unstable suspend substrate.

Therefore, according to the prior art, since the charge is charged between the sus substrate 51 and the storage electrode 57 when the flexible display is manufactured on the sus substrate, the image is dark or the contrast ratio is lowered, that is, kick back. ) Phenomenon (a bright and dark phenomenon) occurs.

Therefore, the present invention has been made to solve the above-mentioned problems of the prior art, the image is dark due to the charge charge between the sus substrate and the storage electrode, the contrast ratio (contrast ratio) can be improved that can be reduced It is an object of the present invention to provide a sub display.

According to another aspect of the present invention, there is provided a flexible display device including: a gate electrode, a storage electrode, and a gate pad formed on an overcoat layer on a sus substrate; A first insulating layer formed on the gate electrode, the storage electrode and the gate pad; A semiconductor layer formed on the first insulating film on the gate electrode; A source electrode, a drain electrode, and a data pad formed on the first insulating layer including the semiconductor layer; A second insulating layer formed on the entire substrate and having a plurality of contact portions respectively exposing the drain electrode, the gate pad and the data pad, and a part of the sus substrate; And a pixel electrode, a gate pad electrode, a data pad electrode, and a substrate contact electrode formed on the second insulating layer and electrically connected to the drain electrode, the gate pad and the data pad, and a sus substrate, respectively, through the plurality of contact parts. Characterized in that comprises a.

In addition, a method of manufacturing a flexible display device according to the present invention for achieving the above object comprises the steps of forming a gate electrode, a storage electrode and a gate pad on an overcoat layer on a sus substrate; Forming a first insulating layer on the overcoat layer including the gate electrode, the storage electrode and the gate pad; Forming a semiconductor layer on the first insulating film on the gate electrode; Forming a source electrode, a drain electrode, and a data pad on the first insulating layer including the semiconductor layer; Forming a second insulating layer having a plurality of contact portions exposing the drain electrode, the gate pad and the data pad, and a part of the suspend substrate, respectively; And forming a pixel electrode, a gate pad electrode, a data pad electrode and a sustain substrate contact electrode electrically connected to the drain electrode, the gate pad and the data pad, and a sus substrate, respectively, through the plurality of contact parts on the second insulating layer. Characterized in that comprises a step.

Hereinafter, a method of manufacturing a flexible display device according to the present invention will be described in detail with reference to the accompanying drawings.

3 is a cross-sectional view illustrating a flexible display device according to the present invention.

4A to 4F are cross-sectional views illustrating a flexible display device according to the present invention.

In the flexible display device according to the present invention, referring to FIGS. 3 and 4A, first, an overcoat layer 103 is deposited on a stainless steel-sustained substrate (SUS) 101, and then a conductive material layer is deposited thereon. Subsequently, the conductive material layer is selectively patterned to form a gate electrode 105 and a storage electrode 107 in the TFT channel portion and the storage portion, respectively. At this time, the gate pad 109 is also formed when the gate electrode 105 is formed.

Next, referring to FIG. 4B, a first insulating layer 111 and a semiconductor layer (not shown) are sequentially deposited on the entire substrate including the gate electrode 105 and the storage electrode 107.

Subsequently, the semiconductor layer (not shown) is selectively patterned to form a semiconductor layer pattern 113 on the gate electrode 105.

Next, referring to FIG. 4C, after depositing a conductive material layer on the first insulating layer 111 including the semiconductor layer pattern 113 and selectively patterning the conductive material layer, source electrodes spaced apart from each other by a predetermined distance, that is, a channel length ( 115 and a drain electrode 117 are formed. In this case, the data pad 119 is also formed when the source electrode 115 and the drain electrode 117 are formed. In this case, the drain electrode 117 also overlaps the storage electrode 107. Therefore, part of the drain electrode 117 is also used as the upper electrode of the capacitor.

Subsequently, referring to FIG. 4D, a thick interlayer insulating film 121, which is a second insulating film, is deposited on the entire substrate including the source electrode 115 and the drain electrode 117, and then protected on the interlayer insulating film 121. Deposit layer 123.

Next, referring to FIG. 4E, a portion of the drain electrode 117, the gate pad 109, the data pad 119, and the sustain substrate 101 may be selectively patterned by the protective layer 123 and the interlayer insulating layer 121. First, second, third, and fourth contact portions 125a, 125b, 125c, and 125d exposing the first and second contact portions 125a, 125b, 125c, and 125d, respectively.

4F, a transparent material such as ITO is deposited on the protective layer 123 including the first, second, third and fourth contact portions 125a, 125b, 125c, and 125d, and then selectively patterned. The pixel electrode 127, the gate pad electrode 129, the data pad electrode 131, and the substrate contact electrode 133 are electrically connected to the drain electrode 117. In this case, the sus substrate 101 is circuitically grounded through the substrate contact electrode 133 which is a TCP channel.

Although not shown in the figure, a black matrix and a color filter layer are formed on an upper substrate (not shown). The black matrix serves to prevent light leakage into a region in which the liquid crystal molecules do not operate, and is mainly formed in a thin film transistor region and between the pixel and the pixel (ie, the gate line and the data line region). In addition, the color filter layer (not shown) is composed of R (Red), B (Blue), G (Green) to implement the actual color.

Although not shown in the drawings, a liquid crystal layer (not shown) is formed between the sus substrate and the upper substrate to complete the flexible display (not shown).

As described above, the method of manufacturing the flexible display device according to the present invention has the following effects.

According to the method of manufacturing the flexible display device according to the present invention, it is possible to ground the dummy portion of the source electrode or the gate TCP to the ground, thereby reducing the kickback phenomenon in which charge is charged between the sus substrate and the storage electrode. Image brightness or contrast ratio can be improved.

It will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the spirit and scope of the invention as defined in the appended claims. And changes may be made without departing from the spirit and scope of the invention.

Claims (9)

An overcoat layer formed on the sus substrate; A gate electrode, a storage electrode, and a gate pad formed on the overcoat layer of the sus substrate; A first insulating layer formed on the overcoat layer including the gate electrode, the storage electrode and the gate pad; A semiconductor layer formed on the first insulating film on the gate electrode; A source electrode, a drain electrode, and a data pad formed on the first insulating layer including the semiconductor layer; A second insulating layer formed on the entirety of the sus substrate and having a plurality of contact portions exposing the drain electrode, the gate pad and the data pad, and a part of the sus substrate, respectively; And A pixel electrode, a gate pad electrode, a data pad electrode, and a sustain substrate contact electrode formed on the second insulating layer and electrically connected to the drain electrode, the gate pad and the data pad, and a sus substrate through the plurality of contact units, respectively; Flexible display device comprising a. The flexible display device of claim 1, wherein the drain electrode is formed on an overcoat layer on the storage electrode and used as an upper electrode of a capacitor. The flexible table market value of claim 1, wherein a passivation layer is formed between the second insulating layer and the pixel electrode, the gate pad electrode, the data pad electrode, and the sustain substrate contact electrode. The flexible display device of claim 1, further comprising: an upper substrate bonded to the sus substrate and having a plurality of color filter layers, and a liquid crystal layer formed between the sus substrate and the upper substrate. Forming an overcoat layer on the sus substrate; Forming a gate electrode, a storage electrode, and a gate pad on the overcoat layer; Forming a first insulating layer on the overcoat layer including the gate electrode, the storage electrode and the gate pad; Forming a semiconductor layer on the first insulating film on the gate electrode; Forming a source electrode, a drain electrode, and a data pad on the first insulating layer including the semiconductor layer; Forming a second insulating film on the first insulating film including the source electrode, the drain electrode, and the data pad; Forming a plurality of contact portions on the second insulating layer and the first insulating layer below to expose the drain electrode, the gate pad and the data pad, and a part of the suspend substrate, respectively; And Forming a pixel electrode, a gate pad electrode, a data pad electrode and a sustain substrate contact electrode electrically connected to the drain electrode, the gate pad and the data pad, and a sus substrate, respectively, through the plurality of contact parts on the second insulating layer; Flexible display device manufacturing method comprising a. The method of claim 5, wherein the drain electrode is formed on the overcoat layer on the storage electrode and used as an upper electrode of the capacitor. The method of claim 5, further comprising forming a passivation layer on the second insulating layer before forming the pixel electrode, the gate pad electrode, the data pad electrode, and the sustain substrate contact electrode. . The method of claim 5, wherein the plurality of contact parts are formed at the same time. The method of claim 5, further comprising: providing an upper substrate having a plurality of color filter layers, bonding the sus substrate and the upper substrate to each other, and forming a liquid crystal layer between the sus substrate and the upper substrate; Flexible display device manufacturing method comprising a.

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