KR20180036738A - A substrate provided with a transparent conductive layer, a liquid crystal panel, and a method for manufacturing a substrate provided with a transparent conductive layer - Google Patents

Abstract

Provided are a substrate provided with a transparent conductive layer with little change in resistance over time, a liquid crystal panel, and a method of manufacturing a substrate provided with the transparent conductive layer. A substrate and a transparent conductive layer are provided as a substrate provided with a transparent conductive layer according to an embodiment of the present invention. The transparent conductive layer is provided on the substrate and includes a transparent conductive layer comprising tin oxide and at least one of niobium oxide, tantalum oxide, and antimony oxide. Thus, in the substrate provided with this transparent conductive layer, the change in resistance with time is small.

Description

A substrate provided with a transparent conductive layer, a liquid crystal panel, and a method for manufacturing a substrate provided with a transparent conductive layer

The present invention relates to a substrate provided with a transparent conductive layer, a liquid crystal panel, and a method of manufacturing a substrate provided with a transparent conductive layer.

(In-plane switching (FPS) system or FFS (fringe field switching) system) in which an electric field of a horizontal direction component is generated on a liquid crystal panel substrate to drive a liquid crystal, cell type liquid crystal panel has the following structure. For example, this structure includes a color filter substrate, a liquid crystal driving electronic circuit for driving the liquid crystal, an opposing substrate having electrodes for sensing sensors for sensing a finger touch, and a liquid crystal disposed therebetween.

In such a liquid crystal panel, an electrode is not formed on the color filter substrate, the color filter is charged, and a malfunction of the display operation is caused. In order to prevent this electrification, there is a technique of providing a transparent conductive layer containing silicon using a high-resistance indium tin oxide as a main material on the surface of a color filter substrate on which a color filter is not formed (see, for example, Patent See Document 1).

[Patent Document 1] Japanese Patent No. 5855948

However, a transparent conductive layer containing indium tin oxide as a main component and containing silicon is exposed to indium tin oxide at its surface. For this reason, the transparent conductive layer is inferior in weather resistance or chemical resistance, and its resistance tends to change over time.

SUMMARY OF THE INVENTION In view of the above circumstances, it is an object of the present invention to provide a method of manufacturing a substrate provided with a transparent conductive layer, a liquid crystal panel, and a transparent conductive layer, have.

In order to achieve the above object, a substrate provided with a transparent conductive layer according to an aspect of the present invention includes a substrate and a transparent conductive layer.

The transparent conductive layer is provided on the substrate and includes at least one of tin oxide, niobium oxide, tantalum oxide, and antimony oxide.

Thus, in the substrate provided with this transparent conductive layer, the change in resistance with time is small.

In the substrate provided with the transparent conductive layer, the content ratio of at least one of the niobium oxide, the tantalum oxide, and the antimony oxide may be 5 wt% or more and 15 wt% or less in the transparent conductive layer.

Thus, in the substrate provided with this transparent conductive layer, the oxide is hardly reduced and the high-resistance state of the transparent conductive layer is maintained.

In the substrate provided with the transparent conductive layer, the sheet resistance of the transparent conductive layer may be 1 × 10 ⁷ (Ω / sq.) Or more and 1 × 10 ¹⁰ (Ω / sq.) Or less.

The transmittance of the transparent conductive layer may be 98.5% or more at a wavelength of 550 nm.

Use of a substrate provided with such a transparent conductive layer having a high light transmittance in an in-cell type liquid crystal panel prevents the charging of the color filter and does not significantly reduce the light transmittance in the liquid crystal panel.

In the substrate provided with the transparent conductive layer, the thickness of the transparent conductive layer may be 5 nm or more and 15 nm or less.

Thus, in the substrate provided with this transparent conductive layer, a transparent conductive layer having appropriate resistance and transmittance is provided on the substrate.

In the substrate provided with the transparent conductive layer, the transparent conductive layer may contain nitrogen.

Thus, in the substrate provided with this transparent conductive layer, the resistance of the transparent conductive layer is adjusted by the addition amount of nitrogen.

In the substrate provided with the transparent conductive layer, the substrate may have a transparent substrate and a color filter.

The transparent substrate may be provided between the transparent conductive layer and the color filter.

As a result, the charging of the color filter is suppressed by the transparent conductive layer.

A liquid crystal panel according to an aspect of the present invention includes a substrate provided with a transparent conductive layer, a counter substrate, and a liquid crystal.

The substrate provided with the transparent conductive layer has a first transparent substrate having a first surface and a second surface, a transparent conductive layer, and a color filter. The transparent conductive layer is provided on the first surface and includes at least one of tin oxide and niobium oxide, tantalum oxide and antimony oxide. A color filter is provided on the second surface.

The counter substrate has a second transparent substrate, an electrode for a sensing sensor provided on the second transparent substrate, and a liquid crystal driving electronic circuit.

The liquid crystal is provided between a substrate provided with the transparent conductive layer and the counter substrate, and is driven and controlled by the liquid crystal driving electronic circuit.

In this liquid crystal panel, the color filter is prevented from being charged by the transparent conductive layer. Further, in this transparent conductive layer, a change in resistance with time is small. As a result, the change over time of the touch sensing function in the liquid crystal panel is small, and reliability is further enhanced.

In the liquid crystal panel, the content ratio of at least one of the niobium oxide, the tantalum oxide, and the antimony oxide may be 5 wt% or more and 15 wt% or less in the transparent conductive layer.

Thus, in the substrate provided with the transparent conductive layer of the liquid crystal panel, the oxide is hardly reduced and the high-resistance state of the transparent conductive layer is maintained.

In the above liquid crystal panel, the sheet resistance of the transparent conductive layer may be 1 x 10 ⁷ (Ω / sq.) Or more and 1 × 10 ¹⁰ (Ω / sq.) Or less.

The transmittance of the transparent conductive layer may be 98.5% or more at a wavelength of 550 nm.

Use of a substrate provided with such a transparent conductive layer having a high light transmittance in an in-cell type liquid crystal panel prevents the charging of the color filter and does not significantly reduce the light transmittance in the liquid crystal panel.

In the above liquid crystal panel, the thickness of the transparent conductive layer may be 5 nm or more and 15 nm or less.

Thus, in this liquid crystal panel, a transparent conductive layer having appropriate resistance and transmittance is provided on the transparent substrate.

In the liquid crystal panel, the transparent conductive layer may contain nitrogen.

Thus, in this liquid crystal panel, the resistance of the transparent conductive layer is adjusted by the addition amount of nitrogen.

Further, in a method of manufacturing a substrate provided with a transparent conductive layer according to an embodiment of the present invention, a target material containing tin oxide and at least one of niobium oxide, tantalum oxide, and antimony oxide, And the content of at least one of the niobium oxide, the tantalum oxide, and the antimony oxide is 5 wt% or more and 15 wt% or less. A transparent conductive layer containing at least one of tin oxide and niobium oxide, tantalum oxide and antimony oxide is formed on a substrate in an atmosphere of a mixed gas of argon and oxygen at an oxygen partial pressure of not less than 0.005 Pa and not more than 0.05 Pa.

By forming the transparent conductive layer in such a mixed gas atmosphere, a desired high resistance transparent conductive layer can be obtained. Reduction of the oxide in the transparent conductive layer is suppressed, and a transparent conductive layer with little change in resistance over time is obtained.

In the method of manufacturing a substrate provided with the transparent conductive layer, nitrogen may be contained in the mixed gas, and the transparent conductive layer may be formed with a nitrogen partial pressure of 0.025 Pa or more and 0.1 Pa or less.

Thus, in the substrate provided with this transparent conductive layer, the resistance of the transparent conductive layer is adjusted by the addition amount of nitrogen.

As described above, according to the present invention, there is provided a substrate having a transparent conductive layer with little change in resistance over time, a liquid crystal panel, and a method of manufacturing a substrate provided with the transparent conductive layer.

1 is a schematic sectional view showing a liquid crystal panel according to the present embodiment.
2 is a schematic graph showing the relationship between the oxygen flow rate and the sheet resistance of the transparent conductive layer when a target material containing tin oxide and niobium oxide is used.
3 is a schematic graph showing the relationship between the oxygen flow rate and the sheet resistance of the ITO layer when a target material made of ITO is used as a comparative example.
Fig. 4 is a schematic graph showing the relationship between the nitrogen flow rate when nitrogen is added to a mixed gas of argon and oxygen and the sheet resistance of the transparent conductive layer. Fig.
5 is a schematic graph showing the light transmittance of the transparent conductive layer.
Fig. 6 is a schematic graph showing changes in sheet resistance of the transparent conductive layer with time (first). Fig.
Fig. 7 is a schematic graph showing a change with time in sheet resistance of the transparent conductive layer (second). Fig.
8 is a schematic graph showing the corrosion resistance of the transparent conductive layer.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each drawing, XYZ axis coordinates may be introduced. Further, the numerical values, drawings and graphs shown below are illustrative and not intended to be limiting.

In the present embodiment, a liquid crystal panel having an in-cell type touch panel function employing the FFS method is exemplified, but the present invention is not limited to this. For example, the liquid crystal panel according to the present embodiment can be applied to a liquid crystal panel of an IPS system. Among the pair of substrates constituting the liquid crystal panel, the liquid crystal driving electronic circuit and the sensing electrode And the electrode is not formed on the other substrate but the color filter is formed.

[Liquid crystal panel]

1 is a schematic sectional view showing a liquid crystal panel according to the present embodiment.

The liquid crystal panel 1 shown in Fig. 1 has a function of displaying an image and a function of a touch panel. The liquid crystal panel 1 includes a substrate 10 provided with a transparent conductive layer, a counter substrate 20, a liquid crystal 40, a polarizing plate 50, a cover glass 60 and a polarizing plate 51. 1, the polarizing plate 51, the counter substrate 20, the liquid crystal 40, the substrate 10 provided with the transparent conductive layer, the polarizing plate 50, and the cover-glass 60 in the Z- Are stacked in order. In the liquid crystal 40, a spacer 41 is provided.

In the liquid crystal panel 1, a backlight is incident on the polarizing plate 51. Further, in the liquid crystal panel 1, the image is viewed through the cover-glass 60. In the liquid crystal panel 1, the touch operation can be performed by touching the cover-glass 60 with the finger 70 or the like. Hereinafter, the structure of each member in the liquid crystal panel 1 will be described in detail.

A substrate 10 provided with a transparent conductive layer has a transparent conductive layer 12 and a color filter substrate 14. The color filter substrate 14 includes a transparent substrate 11 (first transparent substrate) and a color filter 15. The transparent substrate 11 is provided between the transparent conductive layer 12 and the color filter 15. The transparent substrate 11 is, for example, a glass substrate. The transparent conductive layer 12 functions as, for example, an antistatic layer in the liquid crystal panel 1.

The transparent conductive layer 12 is provided on the surface 11a (first surface) of the transparent substrate 11. A transparent conductive layer 12 is tin oxide (SnO ₂₎ and niobium oxide (Nb ₂ O ₃ or Nb ₂ O _5), tantalum oxide (Ta ₂ O ₃ or Ta ₂ O _5), and antimony (Sb ₂ O oxide ₃ or Sb ₂ O ₅ ).

For example, the transparent conductive layer 12 is composed of tin oxide as a main component and at least one of niobium oxide, tantalum oxide, and antimony oxide as subcomponents. Here, the transparent conductive layer 12 may contain elements such as trace aluminum (Al) and zirconium (Zr) which are introduced in the process of manufacturing the target material. Substantially the same effect can be obtained in this embodiment even if the transparent conductive layer 12 contains or does not contain trace elements (Al, Zr, etc.). The subcomponent may be any oxide of a Group 3 element other than the above-mentioned oxides.

In the transparent conductive layer 12, the content of at least one of niobium oxide, tantalum oxide, and antimony oxide is 5 wt% or more and 15 wt% or less. If the content of at least one of niobium oxide, tantalum oxide and antimony oxide is less than 5 wt%, the resistance of the transparent conductive layer 12 becomes low, for example. On the other hand, if the content of at least one of niobium oxide, tantalum oxide and antimony oxide is larger than 15 wt%, for example, the target material used at the time of film formation tends to be easily broken.

The sheet resistance of the transparent conductive layer 12 made of such an oxide is, for example, 1 × 10 ⁷ (Ω / sq.) Or more and 1 × 10 ¹⁰ (Ω / sq.) Or less. If the sheet resistance of the transparent conductive layer 12 is less than 1 x 10 ⁷ (Ω / sq.), For example, the touch signal at the time of touch operation is shielded by the transparent conductive layer 12. On the other hand, if the sheet resistance of the transparent conductive layer 12 is larger than 1 × 10 ¹⁰ (Ω / sq.), For example, the antistatic function of the transparent conductive layer 12 is deteriorated.

The sheet resistance of the transparent conductive layer 12 can be adjusted by changing the content ratio of at least one of niobium oxide, tantalum oxide, and antimony oxide contained in the transparent conductive layer 12. Alternatively, the sheet resistance can be adjusted, for example, by changing the amount of oxygen introduced into the transparent conductive layer 12 at the time of film formation. The transmittance of the transparent conductive layer 12 having such a sheet resistance is 98.5% or more at a wavelength of 550 nm.

In the liquid crystal panel 1 provided with the transparent conductive layer 12, the transparent conductive layer 12 is excellent in weather resistance or chemical resistance, and the oxide included in the transparent conductive layer 12 is hardly reduced. Thus, the resistance of the transparent conductive layer 12 is maintained for a long time in a high resistance state (1 × 10 ⁷ (Ω / sq.) Or more and 1 × 10 ¹⁰ (Ω / sq.)) Or less. As a result, in the liquid crystal panel 1, the touch detection during the touch operation is stabilized, and the charging of the color filter 15 is suppressed. In addition, in the liquid crystal panel 1, the transmittance of light in the transparent conductive layer 12 is increased, so that the light transmittance in the liquid crystal panel is not remarkably reduced, and the image on the liquid crystal panel 1 can be seen more clearly. That is, the operational reliability of the liquid crystal panel 1 is further improved.

The thickness of the transparent conductive layer 12 is 5 nm or more and 15 nm or less. If the thickness of the transparent conductive layer 12 is less than 5 nm, for example, the sheet resistance of the transparent conductive layer 12 becomes higher than the above range, and the antistatic function of the transparent conductive layer 12 is reduced. When the thickness of the transparent conductive layer 12 is larger than 15 nm, for example, the transmittance of the transparent conductive layer 12 is lowered.

The transparent conductive layer 12 may contain nitrogen (N). Nitrogen is contained in the transparent conductive layer 12 as, for example, an impurity element. The sheet resistance of the transparent conductive layer 12 can be adjusted, for example, by changing the addition amount of nitrogen. For example, at the time of forming the transparent conductive layer 12, the ratio of oxygen introduced at the time of film formation is adjusted to such an extent that the transparent conductive layer 12 is not reduced, and the sheet resistance of the transparent conductive layer 12 Can be adjusted by controlling the ratio of nitrogen to be introduced into the reaction zone independently of the ratio of oxygen.

If the transparent conductive layer is made of an ITO (Indium Tin Oxide) layer alone, the ITO layer has low weather resistance or chemical resistance, so that the sheet resistance of the ITO layer decreases with time. As a result, the touch sensing function deteriorates with time in the liquid crystal panel constituted by a single ITO layer. This is considered that the oxygen contained in the ITO layer is detached with time (so-called " missing oxygen ") and the sheet resistance is lowered with time. For this reason, when ITO is deposited on a bonded substrate, the annealing process can not be sufficiently performed, and an ITO layer having a high crystallinity can not be formed. Further, even in a single layer in which Si is added to the ITO layer, the same phenomenon may occur because ITO is exposed on the surface of the single layer.

In order to prevent the oxygen contained in the ITO layer from detaching over time, a method of providing a cap layer for suppressing the release of oxygen in the ITO layer is considered. However, the number of layers of the laminate provided with the cap layer on the ITO layer is smaller than that of the single layer, and the light transmittance of the laminate itself is lowered. As a method of raising the light transmittance of this laminate, there is a method of allowing the cap layer to function as an antireflection layer. However, it is necessary to form the antireflection layer relatively thick, and if this method is employed, the manufacturing cost increases.

As described above, in the liquid crystal panel, it is preferable to use the transparent conductive layer 12 described above.

The color filter 15 is formed on the surface 11b (second surface) of the transparent substrate 11. The color filter 15 is composed of a black matrix formed in a latticed form of black resin or the like and a red colored layer, a green colored layer and a blue colored layer formed in, for example, a stripe shape so as to embed an opening portion of the black matrix. An alignment film (not shown) is formed on the color filter 15.

The openings formed by the black matrix on the lattice correspond to the sub-pixels, and one pixel is composed of three sub-pixels: a red sub-pixel, a green sub-pixel and a blue sub-pixel.

The counter substrate 20 has a transparent substrate 21 (second transparent substrate), and a functional layer 22 including electrodes for sensing sensors and electronic circuits for driving liquid crystals. The transparent substrate 21 is, for example, a glass substrate.

The transparent substrate 21 has a surface 21a and a surface 21b. The functional layer 22 is provided on the surface 21b of the transparent substrate 21. An alignment layer (not shown) is formed on the functional layer 22.

The liquid crystal driving electronic circuit drives the liquid crystal 40. The electrode for the detection sensor constitutes a part of the detection sensor and detects a touch operation on the cover-glass 60 surface.

The functional layer 22 has a pixel electrode, a TFT (Thin Film Transistor), a gate line, a signal line, a common electrode, a common electrode driving line, a driving line for a sensing sensor, and a sensing line for a sensing sensor.

The liquid crystal driving electronic circuit is composed of a pixel electrode, a TFT, a gate line, a signal line, a common electrode, and a common electrode driving line. The liquid crystal driving electronic circuit is driven and controlled by a driving control circuit provided on a driving circuit board (not shown) electrically connected to the liquid crystal panel.

The electrode for the detection sensor is composed of a drive line for the detection sensor, a detection line for the detection sensor, and a common electrode. The detection sensor is composed of such a sensor electrode and a touch position detection control circuit, and the touch position detection control circuit is provided on a drive circuit board (not shown) electrically connected to the liquid crystal panel. By installing the detection sensor, the liquid crystal panel has a touch panel function. The common electrode used for driving the liquid crystal also functions as an electrode for a sensing sensor.

As described above, the counter substrate 20 is provided with a liquid crystal drive electronic circuit for generating an image to be displayed on the display screen of the liquid crystal panel 1, A part of a sensing sensor for sensing a touch by a touch sensor is provided.

When the horizontal plane of the transparent substrate 21 is the XY plane, the gate lines and the signal lines are provided in the X-axis direction and the Y-axis direction through the interlayer insulating film, and TFTs and comb-like pixel electrodes are provided at the intersections. The gate electrode constituting the TFT is electrically connected to the gate line, and the source and the drain constituting the TFT are electrically connected to the signal line and the pixel electrode, respectively.

(1) A plurality of common electrodes corresponding to each pixel are formed in the form of a figure. The TFT, the common electrode, and the pixel electrode are each formed by stacking a TFT, an interlayer insulating film, a common electrode, an interlayer insulating film, and a pixel electrode in this order from the transparent substrate 21 side.

The common drive line is electrically connected to the common electrode, and is formed in the same layer as the signal line, the source, and the drain.

A plurality of drive lines for the detection sensor are formed in the X-axis direction in the same layer as the gate electrode and the gate line. The driving line for the sensing sensor is electrically connected to some common electrodes, and the common electrode connected to the driving electrode for the sensing sensor functions as a driving electrode of the sensing sensor. The drive electrode for the detection sensor is connected to a touch position detection control circuit (not shown), and this touch position detection control circuit outputs a drive signal for touch position detection.

A plurality of detection lines for the detection sensor are formed in the Y-axis direction in the same layer as the source and signal lines. The detection line for the detection sensor is electrically connected to another common electrode which is not electrically connected to the drive line for the detection sensor, and the common electrode connected to the detection line for the detection sensor functions as the detection electrode of the detection sensor. The driving line for the detection sensor is connected to a touch position detection control circuit (not shown), and the touch position detection control circuit receives the detection signal sent from the detection line for the detection sensor. Then, coordinates of the touch position are calculated by analyzing the received detection signal.

In the liquid crystal panel 1, in the display step, a transverse electric field is formed by the liquid crystal driving electronic circuit to drive the liquid crystal 40 and display an image on the liquid crystal panel 1. [ In the touch step, as the finger approaches the display surface, the capacitance between the drive electrode and the detection electrode of the detection sensor decreases, and the touch position of the finger is specified by detecting the change of the capacitance by the detection sensor.

The liquid crystal 40 is provided between the color filter 15 of the substrate 10 provided with the transparent conductive layer and the counter substrate 20. The gap between the color filter 15 and the counter substrate 20 is held by the spacer 41. [ The surface 11b of the transparent substrate 11 on which the color filter 15 is formed faces the surface 21b of the transparent substrate 21 on which the functional layer 22 of the counter substrate 20 is provided. The driving of the liquid crystal 40 is controlled by the liquid crystal driving electronic circuit. The cover-glass 60 is fixed to the polarizing plate 50 by an adhesive layer (not shown).

[Production method of transparent conductive layer]

A method of manufacturing a substrate 10 having a transparent conductive layer as a component of the liquid crystal panel 1 will be described with reference to FIG.

A color filter substrate 14 in which a color filter 15 composed of a black matrix, a red coloring layer, a green coloring layer and a blue coloring layer is formed on the surface 11b of the transparent substrate 11 is prepared.

Next, the transparent conductive layer 12 is formed on the surface 11a of the transparent substrate 11 on which the color filter 15 is not formed. The transparent conductive layer 12 is formed by DC sputtering, for example. As the DC sputtering method, a magnetron DC sputtering method may be employed. Alternatively, the transparent conductive layer 12 may be formed by, for example, AC sputtering. As the AC sputtering method, a magnetron AC sputtering method may be employed. According to the AC sputtering method, when an electrically conductive target material is used, when the transparent conductive layer 12 having a high resistance state is formed (reactive sputtering), the anode can be secured and productivity is excellent.

As the target material, a target material containing tin oxide and at least one of niobium oxide, tantalum oxide and antimony oxide is used. For example, the target material is composed of tin oxide as a main component and at least one of niobium oxide, tantalum oxide, and antimony oxide as subcomponents. Here, a trace amount of an element such as aluminum (Al) or zirconium (Zr) may be introduced into the target material during the manufacturing process of the target material. Even if the target material contains or does not contain trace elements (Al, Zr, etc.), substantially the same effect can be obtained in the present embodiment.

The content of at least one of niobium oxide, tantalum oxide and antimony oxide in the target material is 5 wt% or more and 15 wt% or less. Hereinafter, a case where a target material containing niobium oxide in niobium oxide, tantalum oxide and antimony oxide is used is illustrated. Here, the content of niobium oxide in the target material is, for example, 10 wt%.

For example, a target material containing tin oxide and niobium oxide is used. In the DC sputtering apparatus, the transparent conductive layer 12 is formed on the surface 11a of the transparent substrate 11. The thickness of the transparent conductive layer 12 is, for example, 10 nm. The deposition conditions are as follows.

Target material: tin oxide / niobium oxide (10 wt%)

Discharge gas: argon (Ar) / oxygen (O ₂ )

Gas Total Pressure: 0.1 Pa or more and 1.0 Pa or less

Argon partial pressure: 0.2 Pa (flow rate: 40 sccm)

(Flow rate: 1.0 sccm) or more and 0.05 sccm or less, preferably 0.005 Pa (flow rate: 1.0 sccm) or more and 0.013 Pa (flow rate: 2.5 sccm) or less

Substrate temperature: set at 25 ℃

If an ITO layer of a high resistance state is formed as a transparent conductive layer, it is necessary to increase oxygen partial pressure in the mixed gas at the time of film formation to introduce oxygen into the ITO layer. However, in this method, a large amount of oxygen is introduced into the ITO layer so that oxygen is detached with time, and the sheet resistance thereof is lowered with time.

On the other hand, in the present embodiment, a target material which can obtain the transparent conductive layer 12 in a high resistance state is used even if the oxygen partial pressure in the mixed gas is not increased. The reason for this is explained with reference to FIG.

2 is a schematic graph showing the relationship between the oxygen flow rate and the sheet resistance of the transparent conductive layer when a target material containing tin oxide and niobium oxide is used.

2 is the oxygen flow rate (sccm) at the time of film formation and the vertical axis is the sheet resistance (? / Sq.) Of the transparent conductive layer 12. Fig. 2 shows the results when the transparent conductive layer 12 is left in the air at room temperature and when it is left in the air at 120 占 폚 for 60 minutes. Here, the arrow A means a range of a desired high resistance state (1 x 10 ⁷ (Ω / sq.) To 1 × 10 ¹⁰ (Ω / sq.)). This range is an example, and the high resistance state is not limited to the range shown by the arrow A.

2, when the transparent conductive layer 12 is left in the atmosphere at room temperature (?), When the flow rate of oxygen is in a range from 1.0 sccm to 2.5 sccm and the flow rate is 1.5 sccm, the transparent conductive layer 12 ) Is minimized. The minimum value (1 x 10 ⁸ (? / Sq.)) Is included in the range of the desired high resistance state.

When the transparent conductive layer 12 is left in the atmosphere at 120 占 폚 for 60 minutes (?), The transparent conductive layer 12 is formed at a flow rate of 2.5 sccm in a range of oxygen flow rate of 1.0 sccm to 2.5 sccm, The sheet resistance of the sheet is minimized. This minimum value (1 占⁰⁷ (? / Sq.)) Is within the desired high resistance state range. For comparison, the relationship between the oxygen flow rate and the sheet resistance of the ITO layer when a target material made of ITO is used will be described below.

3 is a schematic graph showing the relationship between the oxygen flow rate and the sheet resistance of the ITO layer when a target material made of ITO is used as a comparative example.

As shown in Fig. 3, in the case of using a target material made of ITO, the oxygen flow rate (the amount of oxygen in the target material) is smaller than that in the case of using a target material containing tin oxide and niobium oxide Oxygen partial pressure) must be increased. For example, oxygen of 4.5 sccm or more is introduced into the ITO layer. However, in such an ITO layer, oxygen sometimes detaches with time.

In contrast, when a target material containing tin oxide and niobium oxide is used, the transparent conductive layer 12 having a desired high resistance state can be obtained without increasing the flow rate (oxygen partial pressure) in the mixed gas. That is, when the target material containing tin oxide and niobium oxide is used, the transparent conductive layer 12 having a desired high resistance state is formed without introducing excess oxygen into the transparent conductive layer 12. In other words, when a target material containing tin oxide and niobium oxide is used, by introducing a small amount of oxygen into the transparent conductive layer 12 as compared with the case of forming the ITO layer, the transparent conductive layer 12 in the high- .

As a result, in the transparent conductive layer 12, the reduction of the oxide is suppressed for a long time and the high-resistance state is maintained for a long time. As a result, the liquid crystal panel 1 is free from deterioration of touch sensitivity, less malfunction due to electrification, and is highly reliable in operation. Further, when a target material containing tin oxide and niobium oxide is used, if the oxygen flow rate is less than 1 sccm (partial pressure of 0.005 Pa), for example, the light transmittance of the transparent conductive layer 12 increases, which is undesirable. When a target material containing tin oxide and niobium oxide is used and oxygen flow rate is larger than 10 sccm (partial pressure 0.05 Pa), for example, a large amount of oxygen is introduced into the transparent conductive layer 12 to form the transparent conductive layer 12 , Oxygen is liable to be detached with time.

The above mixed gas (Ar / O ₂ ) may further contain nitrogen (N ₂ ), and the transparent conductive layer 12 may be formed. In this case, for example, nitrogen (N) is introduced into the transparent conductive layer 12 as an impurity element. The deposition conditions are as follows.

Target material: tin oxide / niobium oxide (10 wt%)

Discharging gas: argon (Ar) / oxygen (O ₂ ) / nitrogen (N ₂ )

Gas Total Pressure: 0.1 Pa or more and 1.0 Pa or less

Argon partial pressure: 0.2 Pa (flow rate: 40 sccm)

(Flow rate: 1.0 sccm) or more and 0.05 sccm or less, preferably 0.005 Pa (flow rate: 1.0 sccm) or more and 0.013 Pa (flow rate: 2.5 sccm) or less

Nitrogen partial pressure: 0.025 Pa (flow rate: 5.0 sccm) or more 0.1 Pa (flow rate: 20 sccm) or less

Substrate temperature: set at 25 ℃

4 is a schematic graph showing the relationship between the flow rate of nitrogen when nitrogen is added to a mixed gas of argon and oxygen and the sheet resistance of the transparent conductive layer.

The horizontal axis in Fig. 4 is the nitrogen flow rate (sccm) at the time of film formation, and the vertical axis is the sheet resistance (? / Sq.) Of the transparent conductive layer 12. 4 shows the results when the transparent conductive layer 12 is left in the air at 120 DEG C for 60 minutes.

As shown in Fig. 4, when the nitrogen flow rate added to the mixed gas (Ar / O ₂ ) is changed, the sheet resistance of the transparent conductive layer 12 changes within a range of a desired high resistance state. For example, if the nitrogen flow rate is increased in the range of 5 sccm to 20 sccm, the sheet resistance of the transparent conductive layer 12 increases with the increase of the nitrogen flow rate. That is, by adjusting the nitrogen flow rate, the sheet resistance of the transparent conductive layer 12 can be controlled.

For example, in the present embodiment, the ratio of oxygen in the mixed gas (Ar / O ₂ ) is adjusted to such an extent that the transparent conductive layer 12 is hardly reduced at the time of forming the transparent conductive layer 12, (12) is formed. As an example, when the transparent conductive layer 12 is left in the atmosphere at 120 캜 for 60 minutes, the oxygen flow rate is adjusted to 2.5 sccm. In this film formation, the sheet resistance of the transparent conductive layer 12 can be controlled to a predetermined resistance by adjusting the ratio of nitrogen independently of the ratio of oxygen.

As a result, the reduction of the oxide is surely suppressed over a long period of time, and the transparent conductive layer 12 adjusted to the desired sheet resistance by the addition amount of nitrogen is obtained.

In addition, in the example of the film forming method, the transparent conductive layer 12 is formed on the color filter substrate 14. The color filter substrate 14 and the counter substrate 20 are opposed in advance and the liquid crystal 40 is injected between the color filter substrate 14 and the counter substrate 20 before the color filter substrate 14 14, the transparent conductive layer 12 may be formed. Also in this case, the film forming conditions of the transparent conductive layer 12 are the same.

[Evaluation of transparent conductive layer]

5 is a schematic graph showing the light transmittance of the transparent conductive layer.

In Fig. 5, the horizontal axis indicates the wavelength (nm), and the vertical axis indicates the light transmittance (%).

5 shows the results when the transparent conductive layer 12 is left in the air at 120 DEG C for 60 minutes. The deposition conditions in Fig. 5 are as follows.

Target material: tin oxide / niobium oxide (10 wt%)

Discharging gas: argon (Ar) / oxygen (O ₂ ) / nitrogen (N ₂ )

Gas Total Pressure: 0.1 Pa or more and 1.0 Pa or less

Argon partial pressure: 0.2 Pa (flow rate: 40 sccm)

Oxygen partial pressure: 0.013 Pa (flow rate: 2.5 sccm)

Nitrogen partial pressure: 0 Pa (flow rate 0 sccm) or more 0.1 Pa (flow rate 20 sccm) or less

Substrate temperature: set at 25 ℃

As shown in Fig. 5, under the above-described film forming conditions in which the partial pressure of nitrogen was varied from 0 Pa (flow rate 0 sccm) to 0.1 Pa (flow rate 20 sccm) or less, the light transmittance spectrum of the transparent conductive layer 12 Are placed on almost the same line. For example, under the above-described film forming conditions in which the nitrogen partial pressure is changed in the range of 0 Pa (flow rate 0 sccm) to 0.1 Pa (flow rate 20 sccm) or less, the transmittance of the transparent conductive layer 12 is 94.0% 98.5% or more at a wavelength of 550 nm, and 99.4% or more at a wavelength of 700 nm. As described above, in this embodiment, the transparent conductive layer 12 having high light transmittance is obtained.

Figs. 6 and 7 are schematic graphs showing changes in sheet resistance of the transparent conductive layer with time. Fig.

The horizontal axis in Figs. 6 and 7 is the time (h), and the vertical axis is the sheet resistance (Ω / sq.).

Fig. 6 shows the results when the transparent conductive layer 12 is left in the air at room temperature.

Fig. 7 shows the results when the transparent conductive layer 12 is left under the conditions of 60 deg. C and steam 90 RH%. The film forming conditions in Figs. 6 and 7 are as follows.

Target material: tin oxide / niobium oxide (10 wt%)

Discharging gas: argon (Ar) / oxygen (O ₂ ) / nitrogen (N ₂ )

Gas Total Pressure: 0.1 Pa or more and 1.0 Pa or less

Argon partial pressure: 0.2 Pa (flow rate: 40 sccm)

Oxygen partial pressure: 0.013 Pa (flow rate: 2.5 sccm)

Nitrogen partial pressure: 0 Pa (flow rate 0 sccm) or more 0.05 Pa (flow rate 10 sccm) or less

Substrate temperature: set at 25 ℃

6 and 7, even if the transparent conductive layer 12 is left in the atmosphere or under constant temperature and humidity conditions, the sheet resistance of the transparent conductive layer 12 is maintained in the desired high resistance state for 200 hours or more have. As described above, according to the present embodiment, the transparent conductive layer 12 with less time-lapse deterioration as the antistatic layer can be obtained.

8 is a schematic graph showing the corrosion resistance of the transparent conductive layer.

8, the abscissa indicates the time (min) in which the transparent conductive layer 12 and the ITO layer are immersed in phosphorus-acetic acid, and the ordinate indicates the sheet resistance (? / Sq.).

The deposition conditions are as follows. Regarding the oxygen partial pressure at the time of film formation, the sheet resistance of the transparent conductive layer 12 and the ITO layer is adjusted to be 1 × 10 ⁸ (Ω / sq.) Or more and 1 × 10 ¹⁰ (Ω / sq.) Or less.

Film forming conditions of the transparent conductive layer 12:

Target material: tin oxide / niobium oxide (10 wt%)

Discharge gas: argon (Ar) / oxygen (O ₂ )

Total gas pressure: 0.21 Pa

Argon partial pressure: 0.2 Pa (flow rate: 40 sccm)

Film thickness: 10 nm

Substrate temperature: set at 25 ℃

Film forming conditions of the ITO layer:

Target material: indium oxide / tin oxide (10 wt%)

Discharge gas: argon (Ar) / oxygen (O ₂ )

Gas total pressure: 0.23 Pa

Argon partial pressure: 0.2 Pa (flow rate: 40 sccm)

Film thickness: 10 nm

Substrate temperature: set at 25 ℃

As shown in Fig. 8, in the ITO layer, the sheet resistance immediately after the film formation was 2.1 占⁰⁹ (? / Sq.). Thereafter, when the ITO layer was immersed in phosphoric acid-acetic acid for 10 minutes, the film thickness of the ITO layer decreased and the sheet resistance rose to 2.5 x 10 ^{14 (} ? / Sq.).

On the other hand, in the transparent conductive layer 12, the sheet resistance immediately after the film formation was 2.0 x 10 ⁸ (? / Sq.). Thereafter, the transparent conductive layer 12 was immersed in phosphoric acid-acetic acid, but the film thickness reduction was suppressed as compared with the ITO layer. For example, the sheet resistance after immersing the transparent conductive layer 12 in phosphoric acid-acetic acid for 5 minutes is 2.8 x 10 ⁸ (Ω / sq.) And the sheet resistance after immersion for 10 minutes is 3.1 × 10 ⁸ (Ω / sq.), And the sheet resistance after immersion for 20 minutes was 2.3 × 10 ⁸ (Ω / sq.). As described above, in the transparent conductive layer 12, even if it was immersed in phosphoric acid-acetic acid, the sheet resistance of the ITO layer was not increased. That is, the corrosion resistance of the transparent conductive layer 12 to the acid is higher than the corrosion resistance of the ITO layer to the acid.

In addition, under the film forming conditions at a film forming temperature of 25 占 폚, the transparent conductive layer 12 and the ITO layer generally become an amorphous layer. Here, in the ITO layer, it is known that the high-temperature annealing treatment improves the crystallinity and increases the corrosion resistance. However, the liquid crystal panel is thinned by the slimming treatment and is separated by the air expansion in the liquid crystal when heated. Therefore, the ITO layer with good crystallinity can not be provided on the liquid crystal panel.

On the other hand, in the present embodiment, the transparent conductive layer 12 can be formed on the color filter substrate 14 at room temperature. Even if the transparent conductive layer 12 is amorphous, since the corrosion resistance is high, a highly reliable liquid crystal panel is realized. In addition, in the liquid crystal panel 1, the high temperature annealing process for the transparent conductive layer 12 becomes unnecessary, and the manufacturing process is simplified.

Table 1 also shows a comparison of the hardness of the transparent conductive layer.

In Table 1, the conditions of the annealing treatment are 240 DEG C for 40 minutes in an atmospheric environment. "HM" is the Martens hardness. "HIT" is the nanoindentation hardness. "HV" is the Vickers hardness. The film thickness is 1000 nm.

As shown in Table 1, the martens hardness, the nanoindentation hardness, and the Vickers hardness of the transparent conductive layer 12 are larger than those of the ITO layer. As a result, the durability of the liquid crystal panel 1 including the transparent conductive layer 12 is further improved.

For example, since the Vickers hardness (HV) of the transparent conductive layer 12 is increased, durability is excellent as compared with the case where the ITO layer is used.

In addition, examples of the transparent conductive material include zinc oxide and titanium oxide. However, it can be seen that the resistance of the zinc oxide layer to phosphorus-acetic acid is inferior to that of the transparent conductive layer 12. On the other hand, the refractive index of the titanium oxide layer is higher than that of the transparent conductive layer 12, and light reflection is less likely to occur than at the interface between the titanium oxide layer and the titanium oxide layer.

As described above, according to the present embodiment, the substrate 10 and the liquid crystal panel 1 provided with the transparent conductive layer with stable operation characteristics over a long period of time can be obtained. Needless to say, the present invention is not limited to the above-described embodiments, but may be modified in various ways.

1: liquid crystal panel
10: A substrate provided with a transparent conductive layer
11: transparent substrate
11a, 11b: surface
12: transparent conductive layer
14: Color filter substrate
15: Color filter
20: opposing substrate
21: transparent substrate
21a, 21b: surface
22: functional layer
40: liquid crystal
41: Spacer
50, 51: polarizer
60: cover-glass
70: Finger

Claims (13)

Substrate, and
A transparent conductive layer provided on the substrate and including at least one of tin oxide, niobium oxide, tantalum oxide, and antimony oxide,
And a transparent conductive layer formed on the transparent conductive layer. The method according to claim 1,
Wherein a content of at least one of the niobium oxide, the tantalum oxide, and the antimony oxide is 5 wt% or more and 15 wt% or less in the transparent conductive layer. 3. The method according to claim 1 or 2,
The sheet resistance of the transparent conductive layer is 1 x 10 ⁷ (Ω / sq.) Or more and 1 × 10 ¹⁰ (Ω / sq.) Or less,
Wherein the transparent conductive layer has a transmittance of 98.5% or more at a wavelength of 550 nm. 4. The method according to any one of claims 1 to 3,
Wherein the transparent conductive layer has a thickness of 5 nm or more and 15 nm or less. 5. The method according to any one of claims 1 to 4,
Wherein the transparent conductive layer contains nitrogen. 6. The method according to any one of claims 1 to 5,
Wherein the substrate has a transparent substrate and a color filter,
Wherein the transparent substrate is provided between the transparent conductive layer and the color filter. A first transparent substrate having a first surface and a second surface; A transparent conductive layer provided on the first surface and comprising at least one of tin oxide, niobium oxide, tantalum oxide, and antimony oxide; And a color filter provided on the second surface,
A counter substrate having a second transparent substrate, an electrode for sensing sensor provided on the second transparent substrate, and a liquid crystal driving electronic circuit,
A liquid crystal which is provided between the substrate provided with the transparent conductive layer and the counter substrate and is driven and controlled by the liquid crystal driving electronic circuit,
And a liquid crystal panel. 8. The method of claim 7,
Wherein the content of at least one of the niobium oxide, the tantalum oxide, and the antimony oxide is 5 wt% or more and 15 wt% or less in the transparent conductive layer. 9. The method according to claim 7 or 8,
The sheet resistance of the transparent conductive layer is 1 x 10 ⁷ (Ω / sq.) Or more and 1 × 10 ¹⁰ (Ω / sq.) Or less,
And the transmittance of the transparent conductive layer is 98.5% or more at a wavelength of 550 nm. 10. The method according to any one of claims 7 to 9,
Wherein the transparent conductive layer has a thickness of 5 nm or more and 15 nm or less. 11. The method according to any one of claims 7 to 10,
Wherein the transparent conductive layer contains nitrogen. A target material comprising tin oxide and at least one of niobium oxide, tantalum oxide and antimony oxide, wherein the content ratio of at least one of the niobium oxide, the tantalum oxide and the antimony oxide in the target material is 5 wt% By weight of tin oxide and at least one of niobium oxide, tantalum oxide and antimony oxide is formed on the substrate in an atmosphere of a mixed gas of argon and oxygen at an oxygen partial pressure of not less than 0.005 Pa and not more than 0.05 Pa, A method for manufacturing a substrate provided with a transparent conductive layer for forming a transparent conductive layer. 13. The method of claim 12,
Wherein the transparent conductive layer is formed by containing nitrogen in the mixed gas and forming the transparent conductive layer with a partial pressure of nitrogen of 0.025 Pa or more and 0.1 Pa or less.

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