KR101874396B1 - Quantum rod luminescent display device and method of fabricating the same - Google Patents

Abstract

The present invention provides a liquid crystal display comprising: a first substrate on which a plurality of pixel regions are defined; A first electrode formed on each pixel region of the first substrate; A quantum rod layer formed on the first electrode and having a plurality of quantum rods oriented in one direction; A second electrode formed on the quantum rod layer; A second substrate facing the first substrate; And a backlight unit provided on an outer surface of the first substrate, and a method of manufacturing the same.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a quantum rod light emitting display device,

BACKGROUND OF THE INVENTION 1. Field of the Invention [0002] The present invention relates to a quantum rod light emitting display, and more particularly, to a quantum rod light emitting display having a maximized light efficiency and a manufacturing method thereof.

2. Description of the Related Art Flat panel displays having excellent characteristics such as thinning, lightening, and low power consumption have been widely developed and applied to various fields.

As a representative flat panel display device, a liquid crystal display device has been widely used and widely used.

However, referring to FIG. 1 (a diagram showing a schematic sectional configuration of a general liquid crystal display device), a liquid crystal display device includes first and second substrates (not shown), an alignment film (not shown), a color filter layer A liquid crystal panel 10 including a liquid crystal layer (not shown), a backlight unit 20 including a plurality of optical films 22, and upper and lower polarizers 31 and 32.

That is, the liquid crystal display device 1 requires a plurality of optical films 22 and polarizing plates 31 and 32 including a liquid crystal layer (not shown) for gray level implementation, A color filter layer (not shown) is required in the liquid crystal panel.

Therefore, in the liquid crystal display device 1, light emitted from a light source (not shown) of the backlight unit 20 passes through the plurality of optical films 22, the color filter layer (not shown) and the polarizing plates 31 and 32 Most of it is lost and the transmittance is decreasing.

That is, when the amount of light emitted from the light source (not shown) of the backlight unit 20 is 100, the amount of light finally transmitted through the liquid crystal display device 1 is about 5 to 10, Is very low.

Therefore, the luminance of the light emitted from the backlight unit 20 must be increased for realizing a proper luminance as a display device, and therefore the power consumption is increased. Furthermore, since the number of parts required for manufacturing is increased, There is a difficulty.

Accordingly, there is a demand for a new flat panel display device which can solve the problem of low transmittance of the liquid crystal display device 1 so as to reduce the power consumption and reduce the manufacturing cost by using a relatively small number of constituent elements.

Meanwhile, an organic electroluminescent device has been proposed, which does not require a separate polarizing plate, a color filter layer and an optical film in response to demands of the time.

Such an organic electroluminescent device is a device that injects electric charge into an organic light emitting layer formed between a cathode, which is an electron injection electrode, and an anode, which is a hole injection electrode, and pairs electrons and holes and then extinguishes light.

Such an organic electroluminescent device can be formed not only on a flexible substrate such as a plastic but also has excellent color sensitivity due to self-luminescence and can be driven at a lower voltage (10 V or less) than a liquid crystal display device, Is relatively small.

However, such an organic electroluminescent device has a large difference in the lifetime of the organic luminescent material of the organic luminescent layer from one color to another. In particular, the blue luminescent material has a relatively small lifetime, .

Therefore, there is a demand for a flat panel display device having a high transmittance, capable of driving a low power consumption and having a lifetime at the level of a liquid crystal display device.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems, and it is an object of the present invention to provide a display device which does not require a polarizing plate and has a large transmission efficiency and has a simple structure compared to a liquid crystal display device, do.

A quantum rod light emitting display according to an embodiment of the present invention includes a first substrate on which a plurality of pixel regions are defined; A first electrode formed on each pixel region of the first substrate; A quantum rod layer formed on the first electrode and having a plurality of quantum rods oriented in one direction; A second electrode formed on the quantum rod layer; A second substrate facing the first substrate; And a backlight unit provided on an outer surface of the first substrate.

The quantum rod layer is patterned for each pixel region, and the pixel region is divided into first, second, and third pixel regions emitting red, green, and blue, and the quantum rod layer includes first, second, The second substrate may have red, green, and blue color filter patterns corresponding to the first, second, and third pixel regions, respectively.

In addition, the pixel region is divided into first, second, and third pixel regions that emit red, green, and blue light, and the quantum rod layer has quantum regions of the same size on the entire display region having the plurality of pixel regions, And a red, green and blue color filter pattern corresponding to the first, second and third pixel regions is formed on the second substrate.

The first substrate is provided with first, second and third pixel regions which are red, green and blue. The quantum rod layer has quantum rods of the same size in each pixel region. Green, and blue color filter patterns corresponding to the first, second, and third pixel regions, respectively.

A gate line and a data line crossing the first substrate to define the pixel regions; And a thin film transistor connected to the gate wiring and the data wiring. The first electrode is connected to the drain electrode of the thin film transistor.

The fact that the plurality of quantum rods are aligned in one direction means that the polarization ratio PR _h in the horizontal direction and the polarization ratio PR _v in the vertical direction are PR _h = I _h / (I _h + I _v ), PR _v = I _v / (I _h + I _v ), the polarization ratio PR _{h in} the horizontal direction or the polarization ratio PR _v in the vertical direction is larger than 0.5 and smaller than 1, that is, 0.5 <PR _h (or PR _v ) &Lt; 1 is satisfied.

The quantum rod is made of only a core or consists of a core and a shell surrounding the core. The shell has a shape having a minor axis and a major axis, and a ratio of minor axis to major axis is 1: 1.1 to 1:30.

The core of the quantum rod has one of a spherical shape, an elliptical shape, a polyhedral shape, and a rod shape, and the shell may have any one of circular, elliptical, and polygonal shapes . At this time, the shell may have a single layer or a multilayer structure, and the shell is made of an alloy, an oxide-based material, or an impurity-doped material.

The core is characterized in that it is made of semiconductors, alloys or mixed materials of group II-VI, III-V, III-VI, VI-IV and IV on the periodic table. The core of the quantum rod may be made of any one of CdSe, CdS, CdTe, ZnO, ZnSe, ZnS, ZnTe, HgSe, HgTe and CdZnSe, In the case of a III-V group, the light emitting layer may be made of any one of InP, InN, GaN, InSb, InAsP, InGaAs, GaAs, GaP, GaSb, AlP, AlN, AlAs, AlSb, CdSeTe, ZnCdSe, PbSe, PbTe, PbS, PbSnTe, and Tl ₂ SnTe ₅ , or a material in which two or more materials are mixed when the material is a Group VI-IV.

An alignment layer or a self-assembled monolayer formed by alignment is formed between the first electrode and the quantum rod layer.

In addition, the first electrode and the quantum rod include a mesogen material having a rod shape, the mesogen material includes a group capable of inducing the quantum rod behavior, and the UV light irradiation And is arranged to be aligned along the alignment direction of the adjacent material.

In addition, the backlight unit generates blue or ultraviolet light having a short wavelength of 430 nm or less.

The backlight unit may include an edge type backlight unit including a reflection plate, a light guide plate disposed on the reflection plate, a light source positioned on a side of the light guide plate, and a plurality of optical sheets positioned on the light guide, A direct-type backlight unit including a light source positioned above the reflection plate, a diffusion plate positioned above the light source, and a plurality of optical sheets positioned on the diffusion plate.

A method of manufacturing a quantum rod light emitting display according to an exemplary embodiment of the present invention includes: forming a first electrode in each pixel region on a first substrate on which a plurality of pixel regions are defined; Forming a quantum rod layer having a plurality of quantum rods oriented in one direction on the first electrode; Forming a second electrode on the quantum rod layer; Positioning the second substrate to face the first substrate; And mounting a backlight unit on an outer surface of the first substrate.

The forming the quantum rod layer having a plurality of quantum rods oriented in one direction may include forming an alignment layer including a main chain and a side chain over the first electrode; Subjecting the alignment layer to surface treatment so that the side chains are aligned in one direction; Forming a quantum rod layer on the surface of the alignment layer; And curing the quantum rod layer.

The surface treatment of the alignment film is characterized by being any one of rubbing, UV light irradiation and ion beam irradiation.

The step of forming the quantum rod layer having the plurality of quantum rods oriented in one direction may include mixing the mesogen material with the quantum rod solution containing the quantum rod, Forming a quantum rod layer by applying a quantum rod liquid onto the first electrode and irradiating the quantum rod layer with UV light to cause polymerization reaction of the mesogen material so that the quantum rod is aligned in one direction And a reactive mesogen method is used.

Forming a gate wiring and a data wiring which intersect each other on the first substrate to define the pixel region before forming the first electrode on the first substrate; Forming a thin film transistor in each pixel region to be connected to the gate wiring and the data wiring; And forming a protective layer having a drain contact hole exposing a drain electrode of the thin film transistor on the thin film transistor, wherein the first electrode is formed in each pixel region through a drain contact hole of the thin film transistor, So as to be in contact with each other.

The quantum rod layer may be formed by spin coating or slit coating to form a quantum rod liquid on the entire display region including a plurality of pixel regions of the first substrate without discrimination of the pixel regions, Jet method using an ink-jet apparatus or a screen printing method using a screen mask.

In addition, when the quantum rod layer is separately formed for each pixel region, the quantum rod layer is formed to have a different quantum rod size for each pixel region representing red, green, and blue.

And forming a color filter layer on the inner surface of the second substrate so that red, green, and blue color filter patterns are sequentially repeated corresponding to the pixel regions, And forming a black matrix at a boundary between the pixel regions.

Since the quantum rod light emitting display device according to the present invention does not require a polarizing plate, the brightness characteristic is lowered by the polarizing plate and the consumption power is increased by providing a brighter light source to improve the lowered luminance characteristic. High luminance characteristics and low power consumption characteristics.

In addition, since the quantum rod provided in the quantum rod layer is oriented in one direction, the light emitted from the backlight unit is more absorbed and fluoresced, thereby further improving the luminance characteristic.

In addition, since the quantum rod display device according to the present invention does not require a polarizer or the like, it is possible to reduce the number of components required for manufacturing the liquid crystal display device, thereby reducing manufacturing cost.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic sectional view of a general liquid crystal display device. Fig.
2 illustrates a form of a quantum rod;
FIG. 3 is a diagram showing the states of electrons and electrons before and after the application of an electric field to the quantum rod. FIG.
4 is a cross-sectional view of a quantum rod light emitting display device according to an embodiment of the present invention.
5A and 5B are cross-sectional views of a quantum rod light emitting display according to first and second modified examples of the embodiment of the present invention.
FIGS. 6A to 6H are cross-sectional views illustrating a method of fabricating a pixel region of a quantum rod light emitting display according to an exemplary embodiment of the present invention.
7A to 7B are diagrams showing an alignment method using an alignment film used for arranging quantum rods in one direction in a quantum rod layer in manufacturing a quantum rod light emitting display according to an embodiment of the present invention.
8 is a diagram showing another alignment method using an alignment film used for arranging quantum rods in one direction in a quantum rod layer in manufacturing a quantum rod light emitting display device according to an embodiment of the present invention.
9A-9B illustrate an alignment method using self-assembled monomolecules used to arrange quantum rods in one direction in a quantum rod layer in the fabrication of a quantum rod light emitting display according to an embodiment of the present invention.
10 is a magnified photograph of the surface of the quantum rod layer after forming the quantum rod layer after the alignment method of the quantum rod is performed during the manufacturing step of the quantum rod light emitting display according to the embodiment of the present invention.
11 is a magnified photograph of a surface of a quantum rod layer formed without applying an alignment method as a comparative example.

Hereinafter, a quantum rod light emitting display according to the present invention will be described in detail with reference to the accompanying drawings.

First, the quantum rod constituting the quantum rod layer, which is the most characteristic structure provided in the quantum rod light emitting display according to the present invention, will be briefly described.

2 is a diagram showing a general form of a quantum rod.

As shown, the quantum rod 156 comprises a core 157 and a shell 158 surrounding the core 157. The quantum rod 156 may include a core 157 and a shell 158 surrounding the core 157. The quantum rod 156 may be omitted from the core 158. In this case, 157).

The core 157 may have a spherical shape, an elliptical shape, a polyhedron shape, or a rod shape, and the shape of the core 157 may be spherical.

On the other hand, when the quantum rod 156 is formed of only the core 157, the core 157 has an elliptical shape or a rod shape.

In addition, when the quantum rod 156 includes a shell 158 that surrounds the core 157, the core 157 may have any of spherical, ellipsoidal, polyhedral, and rod-like shapes, The cutter 158 has a rod shape with a long axis and a short axis. The cut surface cut in the minor axis direction of the quantum rod 156 can take any one of a circle, an ellipse, and a polygonal shape.

In addition, the shell 158 may have a single layer or a multilayer structure, and is formed of a material in which any one or a mixture of two or more materials selected from an alloy, an oxide-based material, or an impurity-doped material is mixed.

At this time, the shell 158 is characterized in that the ratio of the major axis to the minor axis has a range of 1: 1.1 to 1:30, so that the shell 158 can have various ratios.

In addition, the core 157, which is a component of the quantum rod 156 having such a configuration, may be a semiconductor, an alloy or a mixture thereof of II-VI, III-V, III-VI, VI- &Lt; / RTI &gt;

When the core 157 of the quantum rod 156 is made of Group II-VI of the periodic table, one of CdSe, CdS, CdTe, ZnO, ZnSe, ZnS, ZnTe, HgSe, HgTe, CdZnSe, Can be made of a mixed material.

In the case where the core 157 of the quantum rod 156 is made of Group III-V of the periodic table, the InP, InN, GaN, InSb, InAsP, InGaAs, GaAs, GaP, GaSb, AlP, AlN, CdSeTe, ZnCdSe, or a mixture of two or more materials.

When the core 157 of the quantum rod 156 is made of a group VI-IV of the periodic table, it may be formed of any one material selected from the group consisting of PbSe, PbTe, PbS, PbSnTe, and Tl ₂ SnTe ₅ , Lt; / RTI &gt;

The material and the quantum rod 156 having a major axis to minor axis ratio are characterized in that the fluorescence wavelength is varied according to the size of the core 157 even though it is composed of the core 157 of the same material.

That is, as the size of the core 157 becomes smaller, it emits fluorescence of a shorter wavelength, and as the size becomes larger, fluorescence of a longer wavelength is generated.

Thus, the quantum rod is characterized in that it can nearly fluoresce the light of the desired visible region by adjusting the size of the core 157.

The quantum rod 156 made of a material as described above is formed by the core 157 itself or the core 157 as shown in FIG. 3 (the electron and the major state before and after the application of the electric field to the quantum rod) Is formed with a long axis and a short axis.

Therefore, before the electric field is applied in the long axis direction of the shell 158 or the core 157 having the long axis and the short axis, electrons and holes are coupled into the core 157, Electrons e and holes h are spatially separated in the core 157 or between the core 157 and the shell 158 when an electric field is applied in the longitudinal direction of the core 157 to induce separation of the band gap. The amount of light emitted or the amount of light emitted from the quantum rod 156 can be adjusted, so that light emitted from the quantum rod layer made of such a quantum rod can realize a gray level.

This quantum rod 156 has a quantum yield of 100% in theory, which is another feature that can generate very high fluorescence.

Hereinafter, a quantum rod light emitting display device according to the present invention serving as a display device by providing a quantum rod having the above-described characteristics will be described.

FIG. 4 is a cross-sectional view of a quantum rod light emitting display device according to an embodiment of the present invention, showing three neighboring pixel regions, and shows a thin film transistor Tr as a switching element for only one pixel region P . Here, for convenience of description, a region where the thin film transistor is provided in each pixel region is defined as a switching region TrA.

The quantum rod light emitting display 101 according to an embodiment of the present invention includes a first electrode 150 formed separately for each pixel region P and a second electrode 150 formed on the entire display region for displaying an image, A first substrate 110 having a first electrode 160 and a quantum rod layer 155 interposed between the first and second electrodes 150 and 160 and a second substrate 170 facing the first substrate A quantum rod panel 102 made up of a light source, and a backlight unit 180.

In the quantum rod light emitting display device 101 according to an embodiment of the present invention having such a configuration, the quantum rod layer 155 absorbs light emitted from the backlight unit 180, and electrons and holes are recombined internally Fluorescent light.

At this time, the quantum rod light emitting display device 101 applies a voltage to the first and second electrodes 150 and 160 located below and above the quantum rod layer 155, And the quantum rod layer 155 is formed by adjusting the recombination rates of electrons and holes within each of the plurality of quantum rods constituting the quantum rod layer 155, Green, and blue can be generated by forming the quantum rods differently for each pixel region (P) emitting red, green, and blue, so that a full color image can be displayed.

In the quantum-rod-type liquid crystal display device 101 according to the embodiment of the present invention having such a configuration, the first substrate 110 (including the first and second electrodes 150 and 160 and the quantum rod layer 155) Will be described.

For example, aluminum (Al), an aluminum alloy (AlNd), copper (Cu), or the like is formed on the first substrate 110 made of a transparent insulating substrate such as a transparent glass substrate or a flexible plastic substrate. ), A copper alloy, molybdenum (Mo), and a molybdenum alloy (MoTi), are formed in the first direction.

A gate electrode 108 is formed in the switching region TrA in each pixel region P above the first substrate 110 and connected to the gate wiring (not shown).

An inorganic insulating material such as silicon oxide (SiO ₂ ) or silicon nitride (SiNx) is formed on the entire surface of the first substrate 110 over the gate wiring (not shown) and the gate electrode 108, Respectively.

In the switching region TrA above the gate insulating layer 115, an active layer 120a of pure amorphous silicon and an ohmic contact layer of impurity amorphous silicon And source and drain electrodes 133 and 136 are formed on the semiconductor layer 120. The source and drain electrodes 133 and 136 are spaced apart from each other and are in contact with the ohmic contact layer 120b. At this time, the active layer 120a is exposed between the source and drain electrodes 133 and 136 which are spaced apart from each other.

The gate electrode 108, the gate insulating film 115, the semiconductor layer 120, the source and drain electrodes 133 and 136, which are sequentially stacked in the switching region TrA provided in each pixel region P, Film transistor Tr.

A data line 130 intersecting the gate line (not shown) and defining the pixel region P extends in the second direction and is connected to the source electrode (not shown) of the thin film transistor Tr 133, respectively.

At this time, a dummy pattern 121 composed of the first and second semiconductor patterns 121a and 121b is formed under the data line 130 using the same material as the active layer 120a and the ohmic contact layer 120b However, this is an example of the manufacturing process, and the dummy pattern 121 may be omitted.

In the figure, the thin film transistor Tr includes an active layer 120a made of amorphous silicon and a semiconductor layer 120 of the ohmic contact layer 120b, and a bottom electrode (gate electrode) Type bottom gate type. However, it is also possible to provide a polysilicon semiconductor layer, a gate insulating film, a gate electrode, and a semiconductor layer contact hole for exposing the semiconductor layer by providing a semiconductor layer made of polysilicon A top gate type having a structure in which an interlayer insulating film and source and drain electrodes which are in contact with the semiconductor layer of polysilicon through the semiconductor layer contact holes and are spaced apart from each other are sequentially layered.

When a top gate type thin film transistor having the above-described structure is provided, the gate wiring (not shown) is provided on the gate insulating film on which the gate electrode is formed, and the data wiring is provided on the interlayer insulating film.

Next, a protective layer 140 having a flat surface is formed on the data line 130 and the source and drain electrodes 133 and 136. A drain contact hole 143 is formed in the passivation layer 140 to expose the drain electrode 136 of each thin film transistor Tr for each pixel region P.

A first electrode (not shown) is formed on the passivation layer 140 and is in contact with the drain electrode 136 of the thin film transistor Tr through the drain contact hole 143 in each pixel region P 150 are formed.

A gate line (not shown) and a gate line (not shown) are formed on the first electrode 150 and the protective layer 140 exposed between the first electrode 150 and the data line 130 A buffer pattern 152 is formed to overlap the edge of the first electrode 150.

A quantum rod layer 155 formed of a plurality of quantum rods 156 is formed on the first electrode 150 in each pixel region P surrounded by the buffer pattern 152. At this time, the quantum rod layer 155 may be provided with a quantum rod 156 having cores (157 of FIG. 2) of different sizes for each pixel region P emitting red, green, A quantum rod 156 having the same size core (157 in FIG. 2) may be provided.

When the quantum rod layer 155 is provided as the quantum rod 156 having the same size core (157 in FIG. 2) in the entire display region, the second substrate 170 is provided with the quantum rod layer 155 A color filter layer (not shown) having a shape in which red, green, and blue color filter patterns are sequentially repeated is provided.

As a most characteristic feature of the present invention, the plurality of quantum rods 156 constituting the quantum rod layer 155 are arranged in one direction on the entire surface of the display region of the first substrate 110 .

At this time, the degree to which the long axis of the quantum rod 156 is well arranged in one direction, that is, the degree of orderliness, can be found by measuring the polarization ratio. That is, the degree of polarization of the quantum rod layer 155 can be determined by irradiating the horizontally or vertically polarized light toward the quantum rod layer 155 and measuring the amount of light passing through the photomask (not shown).

When the light intensity from the light source (not shown) is I, the light with only the horizontal component is I _h , and the light with only the vertical component is I _v , if the directionality of the quantum rod is not normally given, The polarization ratio (PR)

PR = (I _h - I _v ) / (I _h + I _v ).

In this case, when the quantum rod layer 155 is arranged in one direction, that is, in the horizontal or vertical direction, the polarization ratios PR _h and PR _v in the horizontal and vertical directions are respectively defined as follows.

PR _h = I _h / (I _h + I _v ),

PR _v = I _v / (I _h + I _v )

Therefore, in the quantum rod layer 155, the plurality of quantum rods are well aligned in one direction, meaning that the polarization ratio PR _h in the horizontal direction or the polarization ratio PR _v in the vertical direction is larger than 0.5 and smaller than 1 That is, 0.5 <PR _h or PR _v <1 is satisfied.

In this way, the quantum rod layer 155 is arranged in a state in which the quantum rod 156 is well arranged, so that the light emitted from the backlight unit 180 can be absorbed more effectively to increase the luminance characteristic, This is to realize low power consumption while having high luminance characteristics.

At this time, arranging the quantum rods in one direction in the quantum rod layer 155 will be described in detail through a later manufacturing method.

On the other hand, when the quantum rod 156 having the cores (157 in FIG. 2) having different sizes is provided for each pixel region P representing red, green and blue, the quantum rod 156, 157 of FIG. 2). The smaller the size of the core (157 in FIG. 2), the shorter the wavelength of fluorescence. The larger the size of the core, the longer wavelength fluorescence is generated.

Therefore, in this case, it is necessary to form the quantum rod layer 155a having the largest core (157 in FIG. 2) size (diameter) corresponding to the pixel region P that should exhibit red, and to display green and blue A quantum rod (156 in FIG. 2) having a size smaller than the size of the core (157 in FIG. 2) of the quantum rod (156 in FIG. 2) provided in the pixel region (P) The quantum rod layers 155b and 155c are formed.

Although the quantum rod layer 155 is formed separately for each pixel region P as an example, it is also possible to use a quantum rod light emitting display device according to a modification of the first modified example of the embodiment of the present invention The quantum rod layer 155 may be formed on the entire surface of the display region where a plurality of pixel regions P are provided. In this case, The pattern 152 is omitted.

The second substrate 170 may be a transparent insulating substrate such as the first substrate 110 and may be made of a glass material Or may be made of a plastic material having a flexible property, or may be a sheet or a film made of a polymer material.

On the inner surface of the second substrate 170, a black matrix 173 is formed to correspond to the boundary of the pixel region P and the portion where the thin film transistor Tr is formed.

5A) in which the quantum rod layer 155 is formed on the entire surface of the display region, the black matrix 173 must be provided for preventing light leakage, and the quantum rod layer 155 is formed in each pixel region P) may be omitted.

In the embodiment of the present invention, only the black matrix 173 is provided on the inner surface of the second substrate 170. However, since the quantum rod layer 155 has the same size (156 in Fig. 2) having a core (157 in Fig. 2) having a core (156 in Fig. 2) Green, and blue color filter patterns 175a, 175b, and 175c in the form of sequentially repeating the three pixel regions P adjacent to the region surrounded by the black matrix 173 for full color implementation. The color filter layer 155 may be provided.

Although not shown, an overcoat layer (not shown) may be provided on the entire surface of the second substrate 170 above the black matrix 173 and the color filter layer 155.

4, the quantum rod layer 155 provided on the first substrate 110 may have a different size for each pixel region P which should exhibit red, green, and blue (see FIG. 2 The color filter layer (not shown) provided on the second substrate 170 may be omitted for the purpose of realizing a high luminance characteristic, or the quantum rod 156 may be omitted, It may be provided for realizing a better color reproduction rate as in the second modified example.

4, a backlight unit 180 for supplying light to the quantum rod layer 155 is formed on the lower surface of the quantum rod panel 102 having such a configuration, more precisely on the outer surface of the first substrate 110, .

The backlight unit 180 includes a light source 182, a reflection plate 185, a light guide plate 187 placed on the reflection plate 185, and a plurality of optical sheets 190 disposed on the light guide plate 187, .

In this case, the light source 182 generates light of a short wavelength range, for example, blue visible light or UV light, which is smaller than 450 nm in the characteristics of the present invention. The CCFL (cold cathode fluorescent lamp) ) Or a light emit diode (LED), and in the drawing, the fluorescent lamp is shown as an example.

The light source 182 is disposed on one side of the light guide plate 187 so as to face the light incident portion of the light guide plate 187. When the light source 182 is a fluorescent lamp, have.

The light guide plate 187 spreads the light incident from the light source 182 evenly into the light guide plate 187 while advancing the light through the light guide 182 several times, .

At this time, the light guide plate 187 may include a pattern (not shown) having a specific shape on the back surface to supply a uniform surface light source to the quantum rod panel 102.

In order to guide the light incident into the light guide plate 187, a pattern (not shown) of a specific shape may be formed of an elliptical pattern, a polygon pattern, a hologram pattern, And such a pattern is formed on the lower surface of the light guide plate 187 by a printing method or an injection method.

The reflection plate 185 is disposed on the back surface of the light guide plate 187 and reflects the light that has passed through the back surface of the light guide plate 187 toward the quantum rod panel 102 to improve the brightness of light.

The optical sheet 190 provided on the light guide plate 187 includes a diffusion sheet 188 and at least one light condensing sheet 189.

The backlight unit 180 having such a configuration is an edge type in which the light source 182 is provided on the side surface of the light guide plate 187 and the surface light source is incident on the quantum rod panel 102 by the light guide plate 187 However, the backlight unit 180 may be a direct-type type.

Although not shown in the drawing, a direct drive type backlight unit (not shown) is provided with a driving substrate for LEDs in which fluorescent lamps are arranged as a plurality of light sources at regular intervals or on which a plurality of LEDs are arranged, And a diffusion plate is provided on the top of the light guide plate in place of the light guide plate, and a plurality of optical sheets are provided on the diffusion plate.

Since the quantum rod light emitting display according to the embodiment of the present invention having such a configuration or a modification thereof does not require a polarizing plate for lowering the brightness characteristic, the brightness characteristic is lowered by the provision of the polarizing plate, There is an advantage that a high luminance characteristic and a low power consumption characteristic are provided as compared with a liquid crystal display device in which power consumption is increased by providing a light source that is brighter.

In addition, since the quantum rod provided in the quantum rod layer is oriented in one direction, the light emitted from the backlight unit is more absorbed and fluoresced, thereby further improving the luminance characteristic.

In addition, since the quantum rod display device according to the present invention does not require a polarizer or the like, it is possible to reduce the number of components required for manufacturing the liquid crystal display device, thereby reducing manufacturing cost.

Hereinafter, a method of manufacturing a quantum rod light emitting display device having the above-described configuration according to an embodiment of the present invention will be described.

A quantum rod light emitting display device according to an embodiment of the present invention has a characteristic configuration in a first substrate provided with a quantum rod layer.

6A to 6H are cross-sectional views illustrating a process of fabricating a pixel region of a quantum rod light emitting display according to an exemplary embodiment of the present invention. For convenience of description, a region in which the thin film transistor Tr as a switching element is formed is defined as a switching region TrA.

6A, a first metal material such as aluminum (Al), an aluminum alloy (AlNd), copper (Cu), a copper alloy, and chromium (Cr) is formed on a transparent insulating substrate 110, A first metal layer (not shown) is formed by depositing one or more materials.

Thereafter, a gate wiring (not shown) extending in one direction is formed by patterning the first metal layer (not shown), a gate electrode 108 connected to the gate wiring (not shown) in each pixel region P, .

Next, as shown in Figure 6b, the gate wiring (not shown) and the gate electrode 108 up to such an inorganic insulating material, for example a blanket deposited silicon oxide (SiO ₂₎ or silicon nitride (SiNx) gate insulating film ( 119 are formed on the entire surface.

Next, a pure amorphous silicon layer (not shown), an impurity amorphous silicon layer (not shown), and a second metal material layer (not shown) are formed on the gate insulating layer 115, and these are subjected to diffraction exposure or halftone exposure (Not shown) and the impurity and the pure amorphous silicon layer (not shown) are patterned by patterning the first metal layer (not shown) and the second amorphous silicon layer A semiconductor layer 120 composed of a pure amorphous silicon active layer 120a and an ohmic contact layer 120b of impurity amorphous silicon spaced apart from the active layer 120a by a predetermined distance corresponding to the gate electrode 108, Source and drain electrodes 133 and 136 are formed on the contact layer 120b.

At this time, the gate electrode 108, the gate insulating film 115, and the semiconductor layer 120, which are sequentially stacked in the switching region TrA in each pixel region P, are separated from the source and drain electrodes 133, 136 constitute a thin film transistor Tr which is a switching element.

At the same time, a data line 130 is formed on the gate insulating film 115 so as to intersect the gate line (not shown) and define the pixel region P.

 Meanwhile, in the embodiment of the present invention, a second metal layer (not shown) and an impurity and a pure amorphous silicon layer (not shown) are formed by performing a single mask process including halftone exposure or diffraction exposure A dummy pattern 121 composed of the first and second patterns 121a and 121b is formed under the data line 130 with the same material as the active layer 120a and the ohmic contact layer 120b Is formed.

However, the semiconductor layer 120 is formed by first patterning the impurity and the pure amorphous silicon layer (not shown) by a single mask process, and then a second metal layer (not shown) is formed on the semiconductor layer 120, The dummy pattern 121 formed under the data line 130 is omitted in the case of performing patterning through two masking processes.

6C, a photosensitive organic insulating material such as photo acryl or benzocyclobutene (BCB) is deposited on the entire surface of the data line 130, the thin film transistor Tr and the storage capacitor StgC. Is formed to have a thickness of about 2 탆 to about 3 탆 so as to overcome the step difference of the components located at the bottom to form a protective layer 140 having a flat surface, The drain contact hole 143 exposing the drain electrode 136 is formed.

6D, a transparent conductive material such as indium-tin-oxide (ITO) or indium-zinc-oxide (IZO) is deposited on the passivation layer 140 having the drain contact hole 143. Next, (Not shown) is formed by patterning a conductive material layer (not shown) by performing a masking process, thereby forming a drain electrode 136 of the thin film transistor Tr through the drain contact hole 143 for each pixel region P Thereby forming the first electrode 150 which is in contact therewith.

6E, a buffer layer (not shown) is formed by applying an organic insulating material onto the first electrode 150 or by depositing an inorganic insulating material, and patterning the buffer layer (not shown) A buffer pattern 152 having a shape surrounding each pixel region P is formed at a boundary. Such a buffer pattern 152 may be omitted.

Next, as shown in FIG. 6F, the quantum rod layer 155 is formed by applying a quantum rod solution corresponding to each pixel region P surrounded by the buffer pattern 152.

At this time, the quantum rod layer 155 performs ink jetting for each pixel region P by using an ink jet apparatus (not shown) in a liquid state quantum rod liquid having a plurality of quantum rods, The quantum rod layer 155 having a patterned pattern for each pixel region P can be formed.

Since the quantum rod layer 155 can be formed selectively for each pixel region P by using the screen printing method or the inkjet method, the quantum rod layer 155 can be formed by the quantum rod Green and blue can be fluoresced by quantum rods having different sizes for each pixel region P by varying the sizes of the red, green and blue colors.

Meanwhile, the quantum rod layer 155 may be formed for each pixel region P, or may be formed on the entire surface of the display region without distinction of the pixel region P. FIG. 5A), it is not necessary to form the buffer pattern 152. The buffer pattern 152 is formed by applying the quantum rod solution including the quantum rod to the entire surface through a slit coating apparatus or a spin coating apparatus can do. In this case, when the quantum rod layer 155 is formed on the entire surface of the display area, a quantum rod of the same size is provided. In this case, the second substrate facing the first substrate has a color It is preferable to form a filter layer.

In forming the quantum rod layer 155, the quantum rod layer 155 may be pre-processed before the quantum rod layer 155 is formed to form a state in which the quantum rods in the quantum rod layer 155 are arranged in one direction, The process is preferentially proceeded.

The pre-processing step is an alignment step in which a plurality of quantum rods are arranged in one direction in the quantum rod layer 155.

The alignment process may be any one of an alignment method using an alignment film, a alignment method using a self-aligned monomer, and a method using a reactive mesogen material. The alignment method is not limited to the alignment method described above, Various orientation methods can be used.

7A to 7B (an alignment method using an alignment film used for arranging the quantum rods in one direction in the quantum rod layer in manufacturing the quantum rod light emitting display according to the embodiment of the present invention (Not shown) before the quantum rod layer 155 is formed in a state where the buffer pattern (not shown) is formed, as shown in FIG. An alignment film 181 is formed on the entire surface of the display region over one electrode (not shown). The alignment layer 181 is made of a polymeric material such as polyimide or polyamide and has a main chain and side chains. The alignment layer 181 rubs the surface in one direction, or the alignment layer 181 is made of a photo-alignment material, When any one of the isomerization material, the photo-curable material and the photopolymerizable material is mixed, the side chains are arranged in one direction by UV light or ion beam irradiation.

After the alignment film 181 is formed, as shown in FIG. 7A, the rotating roller 255 wound with the rubbing cloth 250 is rotated so that the surface of the alignment layer 181 and the rubbing cloth 250 are rubbed The side chains of the surface of the alignment film 181 may be oriented in one direction by moving in one direction or the quantum rod in the quantum rod layer may be arranged in one direction in the production of the quantum rod light emitting display device according to the embodiment of the present invention The UV light is irradiated to the alignment film 181 in one direction or by irradiating an ion beam to the alignment film 181 in the same direction as the alignment film 181 So that the side chains are oriented in one direction.

Thereafter, when the quantum rod liquid is applied to the upper portion of the alignment film 181 in a state where the rubbing process (see FIG. 7A) or the irradiation of the UV light or the ion beam (see FIG. 8) The quantum rods are arranged in one direction.

Although the method using this alignment film 181 is not shown in the drawings other than the above-described method, a four-sided vapor deposition method may also be used.

In the above-mentioned four-sided deposition method, silicon oxide is deposited on the substrate at an angle with respect to an inorganic material such as oxide and fluoride, and the deposition conditions such as deposition angle, deposition rate, vacuum degree, substrate temperature, (Angle of incidence) of the quantum rod applied on the quantum rod can be changed so that the quantum rod is arranged to be parallel or perpendicular to the deposition angle.

On the other hand, the alignment method using the self-assembled monolayer is similar to that of the self-assembled monolayer used for arranging the quantum rods in one direction in the quantum rod layer in manufacturing the quantum rod light emitting display according to the embodiment of the present invention A first substrate 110 on which a buffer pattern 152 is formed to expose the first electrode 150 is formed, as shown in FIG. 1B, illustrating a self-assembled monolayer film formed by a dipping method, (Self-assembled monolayers) process in which the first electrode 150 is exposed to a chemical solution 315 which reacts preferentially with a transparent conductive material forming the first electrode 150 using a dipping or spraying method, The monolayer monolayer 310 is formed on the surface of the substrate 150. The self-assembled monolayer 310 is arranged in one direction by acting as a side chain of the alignment layer (181 in FIG. 7A). Further, the self-assembled monolayer 310 has a tendency to react with and bond with a specific material, And the quantum rod layer 155 is formed by applying the quantum rod liquid on the quantum rod layer 155. The quantum rod layer 155 has a function of arranging the quantum rods in one direction.

Thus, when the quantum rod liquid is applied onto the first substrate 110 on which the self-assembled monolayer film 310 is formed, the quantum rods are oriented in one direction as the quantum rods align on the alignment film (181 in FIG. 7A).

On the other hand, the reactive mesogen orientation method is a method in which a mesogen material, that is, a mesogenic material, that is, a material capable of inducing a quantum rod behavior, is added to a quantum rod liquid without forming an alignment film or a self-assembled monolayer Screen printing, spin coating, or bar coating on the first electrode, UV light is applied to the applied quantum rod layer 155, And the polymerization reaction is generated by irradiation, and the properties are arranged in the same direction along the orientation of the adjacent material, that is, the quantum rod.

When such an orientation method using a reactive mesogen is used, the quantum rod is positioned in one direction by the mesogen group, and the mesogens and the quantum rods, which are gradually located around the quantum rod and the quantum rod, are continuously arranged in one direction.

10 (the present invention is directed to the method of orienting the quantum rods in the manufacturing step of the quantum rod light emitting display device according to the embodiment, and after forming the quantum rod layer, the surface of the quantum rod layer is enlarged It can be seen that a plurality of quantum rods provided in the quantum rod layer are well arranged in one direction.

As a comparative example, referring to Fig. 11 (a photograph of an enlarged image of the surface of a quantum rod layer formed without applying an alignment method as a comparative example), in the case of a quantum rod layer formed without performing the alignment process, Direction and is disorderless without directionality.

On the other hand, referring to FIG. 6F, the plurality of quantum rods included in the quantum rod layer 155 are arranged in one direction.

Next, the quantum rod layer 155 in which the quantum rods are arranged in one direction is cured to keep the quantum rods arranged in one direction.

Next, as shown in FIG. 6G, a transparent conductive material such as indium-tin-oxide (ITO) or indium-zinc-oxide (IZO) is deposited on the cured quantum rod layer 155 on the entire display region The second electrode 160 is formed to complete the first substrate 110.

6H, a black matrix 173 is formed on the inner surface of the second substrate 170 facing the first substrate 110 so as to correspond to the boundaries of the pixel regions P, A color filter layer (not shown) having red, green, and blue color filter patterns sequentially formed in an area surrounded by the black matrix 173 is formed, or an overcoat layer (not shown) having a flat surface is formed .

The quantum rod panel 102 is formed by joining together the first and second substrates 110 and 170. The quantum rod panel 102 has a light source 182, a light guide plate 187, The quantum rod light emitting display device 101 according to the embodiment of the present invention is completed by mounting a backlight unit 180 including a plurality of optical sheets 190 and a plurality of optical sheets 190.

The present invention is not limited to the above-described embodiments, and various changes and modifications may be made without departing from the spirit of the present invention.

101: Quantum rod light emission display device 102: Quantum rod panel
110: first substrate 108: gate electrode
115: gate insulating film 120: semiconductor layer
120a: active layer 120b: ohmic contact layer
121: dummy patterns 121a and 121b: first and second dummy patterns
130: data line 133: source electrode
136: drain electrode 140: protective layer
143: drain contact hole 150: first electrode
152: buffer pattern 155: quantum road layer
155a, 155b, and 155c: quantum rod layers that fluoresce red, green, and blue, respectively
160: second electrode 170: second substrate
173: Black matrix 180: Backlight unit
182: light source 183: lamp guide
185: reflector 187: light guide plate
188: diffusion sheet 188: condensing sheet
190: optical sheet P: pixel area
Tr: thin film transistor TrA: switching region

Claims (26)

A first substrate on which a plurality of pixel regions are defined;
A first electrode formed on each pixel region of the first substrate;
A quantum rod layer formed on the first electrode and having a plurality of quantum rods oriented in one direction;
A second electrode formed on the quantum rod layer;
A second substrate facing the first substrate;
A backlight unit provided on an outer surface of the first substrate,
/ RTI &gt;
When the plurality of quantum rods are oriented in one direction,
When the polarization ratio PR _h in the horizontal direction and the polarization ratio PR _v in the vertical direction are defined as PR _h = I _h / (I _h + I _v ) and PR _v = I _v / (I _h + I _v ) Means that the polarization ratio PR _{h in the} horizontal direction or the polarization ratio PR _v in the vertical direction is larger than 0.5 and smaller than 1, that is, 0.5 <PR _h (or PR _v ) <1.
The method according to claim 1,
The quantum rod layer is patterned for each pixel region, and the pixel region is divided into first, second, and third pixel regions emitting red, green, and blue, and the quantum rod layer includes first, second, And a quantum rod having a different size for each region.
The method according to claim 1,
Wherein the second substrate is provided with red, green, and blue color filter patterns corresponding to the first, second, and third pixel regions.
The method according to claim 1,
The pixel region is divided into first, second, and third pixel regions emitting red, green, and blue, and the quantum rod layer has a uniform quantum load on the entire display region having the plurality of pixel regions, And a red, green, and blue color filter patterns corresponding to the first, second, and third pixel regions are formed on the second substrate.
The method according to claim 1,
The first substrate is provided with first, second and third pixel regions which exhibit red, green and blue. The quantum rod layer has quantum rods of the same size in each pixel region,
Wherein the second substrate is provided with red, green, and blue color filter patterns corresponding to the first, second, and third pixel regions.
The method according to claim 1,
A gate line and a data line crossing the first substrate to define the pixel regions;
Wherein the first electrode is connected to the drain electrode of the thin film transistor, and the first electrode is connected to the drain electrode of the thin film transistor.


delete The method according to claim 1,
The quantum rod includes:
Core,
Or a core and a shell surrounding the core,
Wherein the shell has a shape having a minor axis and a major axis, and a ratio of the minor axis to the major axis is 1: 1.1 to 1:30.
9. The method of claim 8,
Wherein the core of the quantum rod has one of a spherical shape, an elliptical shape, a polyhedral shape, and a rod shape,
Wherein the cut surface of the shell cut in the direction of the minor axis of the quantum rod is in the form of a circle, an ellipse, or a polygonal shape.
10. The method of claim 9,
Wherein the shell comprises a single layer or multilayer structure.
11. The method of claim 10,
Wherein the shell is made of an alloy, an oxide-based material, or an impurity-doped material.
The method according to claim 1,
Wherein the core of the quantum rod is made of a semiconductor, an alloy, or a mixed material of group II-VI, III-V, III-VI, VI-IV and IV on the periodic table.
13. The method of claim 12,
The core of the quantum rod may be made of any one material selected from the group consisting of CdSe, CdS, CdTe, ZnO, ZnSe, ZnS, ZnTe, HgSe, HgTe and CdZnSe,
A material composed of any one of InP, InN, GaN, InSb, InAsP, InGaAs, GaAs, GaP, GaSb, AlP, AlN, AlAs, AlSb, CdSeTe, ZnCdSe, or a mixture of two or more substances Lt; / RTI &gt;
If made of a Ⅵ-Ⅳ group, PbSe, PbTe, PbS, PbSnTe , Tl 2 SnTe 5 by any one of or made or is characterized by a quantum load emitting display device formed of more than one material is a composite material.
The method according to claim 1,
Wherein the alignment film or the self-assembled monolayer film is formed between the first electrode and the quantum rod layer. The method according to claim 1,
Wherein the first electrode and the quantum rod include a mesogen material having a rod shape and the mesogen material includes a group capable of inducing the quantum rod behavior, Wherein the quantum rod light emitting display device is a material that generates a polymerization reaction and is arranged along the alignment direction of the adjacent material.
The method according to claim 1,
Wherein the backlight unit generates blue or ultraviolet light having a short wavelength of 430 nm or less.
The method according to claim 1,
The backlight unit includes:
An edge type backlight unit including a reflective plate, a light guide plate disposed on the reflective plate, a light source positioned on a side of the light guide plate, and a plurality of optical sheets positioned on the light guide,
And a direct backlight unit including a reflection plate, a light source positioned above the reflection plate, a diffusion plate positioned above the light source, and a plurality of optical sheets positioned on the diffusion plate.
Forming a first electrode in each pixel region on a first substrate on which a plurality of pixel regions are defined;
Forming a quantum rod layer having a plurality of quantum rods oriented in one direction on the first electrode;
Forming a second electrode on the quantum rod layer;
Positioning the second substrate to face the first substrate;
Mounting a backlight unit on the outer surface of the first substrate
Lt; / RTI &gt;
When the plurality of quantum rods are oriented in one direction,
When the polarization ratio PR _h in the horizontal direction and the polarization ratio PR _v in the vertical direction are defined as PR _h = I _h / (I _h + I _v ) and PR _v = I _v / (I _h + I _v ) Means that the polarization ratio PR _{h in the} horizontal direction or the polarization ratio PR _v in the vertical direction is larger than 0.5 and smaller than 1, that is, 0.5 <PR _h (or PR _v ) <1. Gt;
19. The method of claim 18,
Wherein forming a quantum rod layer having a plurality of quantum rods oriented in one direction comprises:
Forming an alignment layer comprising a main chain and side chains over the first electrode;
Subjecting the alignment layer to surface treatment so that the side chains are aligned in one direction;
Forming a quantum rod layer on the surface of the alignment layer;
The step of curing the quantum rod layer
Emitting device according to claim 1.
20. The method of claim 19,
Wherein the surface treatment of the alignment film is any one of rubbing, UV light irradiation and ion beam irradiation.
19. The method of claim 18,
Wherein forming a quantum rod layer having a plurality of quantum rods oriented in one direction comprises:
The quantum rod including the mesogen material is applied onto the first electrode to form the quantum rod layer, and the quantum rod layer is formed on the quantum rod layer, Wherein the quantum rod is irradiated with UV light to cause polymerization reaction of the mesogen material so that the quantum rod is aligned in one direction.
19. The method of claim 18,
Forming gate wirings and data wirings crossing each other on the first substrate to define the pixel regions before forming the first electrodes on the first substrate;
Forming a thin film transistor in each pixel region to be connected to the gate wiring and the data wiring;
Forming a protective layer having a drain contact hole exposing a drain electrode of the thin film transistor over the thin film transistor
Wherein the first electrode is formed in each pixel region so as to contact the drain electrode of the thin film transistor through the drain contact hole.
19. The method of claim 18,
The quantum-
The quantum rod liquid may be formed on the entire surface of the display region including the plurality of pixel regions of the first substrate by performing spin coating or slit coating,
Or the quantum rod liquid is formed so as to be separated for each pixel region using an inkjet method using an inkjet apparatus or a screen printing method using a screen mask.
19. The method of claim 18,
Wherein the quantum rod layer is formed so as to have different quantum rod sizes for pixel regions representing red, green, and blue colors when the quantum rod layers are separately formed for each pixel region.
25. The method according to claim 23 or 24,
Forming a color filter layer on the inner surface of the second substrate so that red, green, and blue color filter patterns are sequentially repeated corresponding to the pixel regions;
Emitting device according to claim 1.
26. The method of claim 25,
And forming a black matrix on the inner surface of the second substrate at the boundaries of the pixel regions.

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