Abstract:
The present invention provides an array substrate and a manufacturing method thereof, a display panel and a display device, belongs to a field of black-matrix-less display technology, and can solve problems that a conductive reflecting structure in a display panel of prior art affects display effect and external visibility. The array substrate of the present invention comprises a conductive reflecting structure and metal particles provided above the conductive reflecting structure.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to the field of black matrix less display technology, and particularly relates to an array substrate and a manufacturing method thereof, a display panel and a display device. 
       BACKGROUND OF THE INVENTION 
       [0002]    In order to simplify structure, increase aperture ratio or the like, a black matrix less (BM-less) technology has emerged. Specifically, there is no black matrix provided at a position corresponding to an opaque conductive reflecting structure such as lead wire in an array substrate for blocking light, because the opaque conductive reflecting structure such as lead wire itself can block light from a backlight source. For example, in a display panel, there may be no black matrix provided at a position corresponding to a data line, and since the data line is generally provided in a same layer as a source and a drain, it is also referred to as SD BM-less structure. 
         [0003]    As shown in  FIG. 1 , in a display panel, although there is no light directly emitted out at a conductive reflecting structure  1  (such as data line), since the conductive reflecting structure is formed of reflecting metal, the upper surface thereof is a smooth reflecting surface, thus ambient light from outside of the display panel may be mirror-reflected at the upper surface of the conductive reflecting structure  1 , resulting in the conductive reflecting structure (such as data line) being conspicuous when viewed from the outside, display effect of the display panel is affected and external visibility thereof is reduced. 
       SUMMARY OF THE INVENTION 
       [0004]    In view of problems that display effect and external visibility of a display panel of prior art are affected by a conductive reflecting structure therein, the present invention provides an array substrate which can achieve a good display effect and a high external visibility and a manufacturing method thereof, a display panel comprising the array substrate, and a display device comprising the display panel. 
         [0005]    A technical solution of the present invention is an array substrate, comprising: 
         [0006]    a conductive reflecting structure; and 
         [0007]    metal particles provided above the conductive reflecting structure. 
         [0008]    Preferably, the array substrate further comprises a transparent metal oxide layer provided above the conductive reflecting structure, the metal particles are formed on the transparent metal oxide layer, and the metal particles are formed by aggregating metal in the transparent metal oxide layer. 
         [0009]    Preferably, the transparent metal oxide layer is an indium tin oxide layer, and the metal particles are indium particles. 
         [0010]    Preferably, the conductive reflecting structure comprises one or more of a gate line, a data line, and a common electrode line. 
         [0011]    Preferably, the array substrate further comprises a transparent electrode, and the transparent metal oxide layer is formed in a same layer as the transparent electrode. 
         [0012]    Further preferably, the transparent electrode is a pixel electrode or a common electrode. 
         [0013]    Preferably, the transparent metal oxide layer is in contact with the conductive reflecting structure. 
         [0014]    Another technical solution of the present invention is a manufacturing method of above array substrate, comprising steps of: 
         [0015]    forming a conductive reflecting structure; and 
         [0016]    forming metal particles above the conductive reflecting structure. 
         [0017]    Preferably, the step of forming metal particles above the conductive reflecting structure comprises steps of: 
         [0018]    forming a transparent metal oxide layer above the conductive reflecting structure, and forming the metal particles on the transparent metal oxide layer by aggregating metal in the transparent metal oxide layer. 
         [0019]    Preferably, the step of forming the metal particles on the transparent metal oxide layer by aggregating metal in the transparent metal oxide layer comprises: 
         [0020]    using silane as operating gas, performing a plasma process on the transparent metal oxide layer. 
         [0021]    Preferably, operating parameters of the plasma process include: silane flow rate: 200˜800 sccm; gas pressure: 1400˜2000 mtorr; plasma power: 1000˜1600 W. 
         [0022]    Preferably, the steps of forming a transparent metal oxide layer above the conductive reflecting structure, and forming the metal particles on the transparent metal oxide layer by aggregating metal in the transparent metal oxide layer comprise: 
         [0023]    sequentially forming a transparent metal oxide material layer and a photoresist layer; 
         [0024]    performing an exposure process and a developing process on the photoresist layer to retain a photoresist layer with a first thickness in a first region corresponding to a transparent electrode, retain a photoresist layer with a thickness less than the first thickness in a second region corresponding to the conductive reflecting structure, and there is no photoresist layer retained in other regions; 
         [0025]    removing an exposed transparent metal oxide material layer to form the transparent electrode and the transparent metal oxide layer; 
         [0026]    removing the photoresist layer in the second region, and simultaneously thinning the photoresist layer in the first region but retaining a certain thickness thereof; 
         [0027]    aggregating metal in the exposed transparent metal oxide layer to form the metal particles on the surface thereof; 
         [0028]    removing the remaining photoresist layer in the first region. 
         [0029]    Further another technical solution of the present invention is a display panel comprising above array substrate and an opposite substrate which are aligned and assembled with each other. 
         [0030]    Still another technical solution of the present invention is a display device comprising above display panel. 
         [0031]    In above technical solutions, “A is provided in a same layer as B” indicates that A and B are formed by a same material layer, thus they are in a same layer in a stacked relationship, but distances from them to a base substrate may be different. 
         [0032]    Metal particles are provided above the conductive reflecting structure of the array substrate in the present invention, thus, for a BM-less display panel, a diffuse reflection is produced at surfaces of the metal particles when external ambient light irradiates on the conductive reflecting structure, the reflected light emits in different directions, thus influence of the conductive reflecting structure on display effect is avoided and the external visibility is increased. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0033]      FIG. 1  is a schematic diagram showing that a mirror reflection is produced by a conductive reflecting structure of an existing array substrate; 
           [0034]      FIG. 2  is a schematic diagram showing that a diffuse reflection is produced by a conductive reflecting structure of an array substrate in accordance with an embodiment of the present invention; 
           [0035]      FIG. 3  is a top view diagram of a scanning electron microscope photograph of indium particles in an array substrate in accordance with an embodiment of the present invention; 
           [0036]      FIG. 4  is a side view diagram of a scanning electron microscope photograph of indium particles in an array substrate in accordance with an embodiment of the present invention; 
           [0037]      FIG. 5  is a structural schematic diagram of an array substrate formed with metal particles in accordance with an embodiment of the present invention ( FIG. 5  does not show a gate insulation layer); 
           [0038]      FIG. 6  is a cross-sectional structural schematic diagram of  FIG. 5  taken along A-A′; 
           [0039]      FIG. 7  is a structural schematic diagram of an array substrate formed with a data line in accordance with an embodiment of the present invention; 
           [0040]      FIG. 8  is a structural schematic diagram of the array substrate of  FIG. 7  formed with a photoresist layer; 
           [0041]      FIG. 9  is a structural schematic diagram of the photoresist layer of the array substrate of  FIG. 8  subjected to exposure and developing; 
           [0042]      FIG. 10  is a structural schematic diagram of the array substrate of  FIG. 9  formed with a pixel electrode; 
           [0043]      FIG. 11  is a structural schematic diagram of the array substrate of  FIG. 10  subjected to removing of a part of the photoresist layer; 
           [0044]      FIG. 12  is a structural schematic diagram of the array substrate of  FIG. 11  formed with metal particles. 
       
    
    
     REFERENCE SIGNS 
       [0000]    
       
         
           
               1 , conductive reflecting structure;  2 , transparent metal oxide material layer; 
               21 , transparent metal oxide layer;  211 , metal particles;  22 , transparent electrode; 
               3 , data line;  31 , source;  32 , drain;  4 , pixel electrode;  51 , gate line;  511 , gate; 
               52 , common electrode line;  59 , gate insulation layer;  6 , active region; 
               8 , photoresist layer;  9 , base substrate. 
           
         
       
     
       DETAILED DESCRIPTION OF THE EMBODIMENTS 
       [0050]    In order to make persons skilled in the art better understand technical solutions of the present invention, detailed descriptions of the present invention will be provided below in conjunction with drawings and embodiments. 
       First Embodiment 
       [0051]    As shown in  FIGS. 2-6 , the present embodiment provides an array substrate comprising: 
         [0052]    a conductive reflecting structure  1 ; and 
         [0053]    metal particles  211  provided above the conductive reflecting structure  1 . 
         [0054]    Preferably, the array substrate further comprises a transparent metal oxide layer  21  provided above the conductive reflecting structure  1 , the metal particles  211  are formed on the transparent metal oxide layer  21 , and the metal particles  211  are formed by aggregating metal in the transparent metal oxide layer  21 . 
         [0055]    In other words, the array substrate comprises a conductive reflecting structure  1 , which is capable of not only conducting electricity but also reflecting light and is provided on a base substrate  9 , the conductive reflecting structure  1  is generally formed of metal such as molybdenum, niobium, copper, aluminum or alloy thereof. A transparent metal oxide layer  21  formed of transparent metal oxide material (such as indium tin oxide) may be provided above the conductive reflecting structure  1 , the transparent metal oxide layer  21  is further away from the base substrate  9  than the conductive reflecting structure  1 , and metal particles  211  are formed on a surface of the transparent metal oxide layer  21  by aggregating metal in the transparent metal oxide layer  21 . 
         [0056]    The transparent metal oxide layer  21  is provided above the conductive reflecting structure  1  of the array substrate in the present embodiment, and the metal particles  211  are formed on the transparent metal oxide layer  21 , that is, the metal particles  211  are provided above the conductive reflecting structure  1 . As shown in  FIG. 2 , for a BM-less display panel, a diffuse reflection is produced at surfaces of the metal particles  211  when external ambient light is incident at the conductive reflecting structure  1 , the reflected light emits in different directions, thus influence of the conductive reflecting structure  1  on display effect is avoided and the external visibility is increased. 
         [0057]    Specifically, the above array substrate may be applied in a liquid crystal display panel or an organic light emitting diode (OLED) display panel, as long as the conductive reflecting structure  1  is provided therein. 
         [0058]    Preferably, the transparent metal oxide layer  21  is an indium tin oxide layer, and the metal particles  211  are indium particles. 
         [0059]    In other words, the transparent metal oxide layer  21  is preferably formed of indium tin oxide, and correspondingly the metal particles  211  are indium metal particles. This is because, indium tin oxide is a general material used in the array substrate, thus if the transparent metal oxide layer  21  is formed of indium tin oxide, the transparent metal oxide layer  21  may be provided in a same layer as other structures such as a transparent electrode  22 , thereby the manufacturing process is simplified. 
         [0060]    Specifically, morphology of the indium particle is as shown in  FIGS. 3 and 4 , the diameter of the indium particle ranges from about 0.5 μm to about 5 μm. 
         [0061]    Preferably, as shown in  FIGS. 5 and 6 , the array substrate further comprises a transparent electrode  22 , and the transparent metal oxide layer  21  is formed in a same layer as the transparent electrode  22 . Further preferably, the transparent electrode  22  is a pixel electrode  4  or a common electrode. 
         [0062]    In other words, the array substrate preferably further comprises a transparent electrode  22  also formed of transparent metal oxide material, and the transparent metal oxide layer  21  and the transparent electrode  22  may be synchronously formed in a same layer, thereby the manufacturing process of the array substrate is simplified. Specifically, for a liquid crystal display panel, the transparent electrode  22  may be a pixel electrode  4  or a common electrode. Certainly, the transparent electrode  22  may also be any other well-known electrode such as an anode in the array substrate in an organic light emitting diode display panel. 
         [0063]    Preferably, the conductive reflecting structure  1  comprises one or more of a gate line  51 , a data line  3 , and a common electrode line  52 . 
         [0064]    In other words, the conductive reflecting structure  1  is preferably various lead wires in the array substrate, this is because, in an aspect, the lead wire is the most common conductive reflecting structure  1  in the array substrate and has the most obvious impact on the display effect; in another aspect, the lead wire generally only needs its own conductivity and does not need to be connected with other structures, thus the function thereof will not be affected by forming the transparent metal oxide layer  21  thereon. 
         [0065]    Certainly, it should be understood that, the conductive reflecting structure  1  may be any other well-known structure capable of conducting electricity and reflecting light, such as a source  31 , a drain  32 , a gate  511 , rather than the lead wire. 
         [0066]    Preferably, the transparent metal oxide layer  21  is in contact with the conductive reflecting structure  1 . 
         [0067]    In other words, as shown in  FIG. 6 , the transparent metal oxide layer  21  is preferably directly provided on the conductive reflecting structure  1  and there is no other layer (such as insulation layer) therebetween, which facilitates the transparent metal oxide layer  21  accurately covering the conductive reflecting structure  1 , and since transparent metal oxide material is generally conductive, it facilitates improvement of conductivity of the conductive reflecting structure  1  when the transparent metal oxide layer  21  is in contact with the conductive reflecting structure  1 . 
         [0068]    As shown in  FIGS. 7 to 12 , the present embodiment also provides a manufacturing method of above array substrate, comprising steps of: 
         [0069]    forming a conductive reflecting structure  1 ; and 
         [0070]    forming metal particles  211  above the conductive reflecting structure  1 . 
         [0071]    Preferably, the step of forming metal particles  211  above the conductive reflecting structure  1  comprises steps of: 
         [0072]    forming a transparent metal oxide layer  21  above the conductive reflecting structure  1 , and forming the metal particles  211  on the transparent metal oxide layer  21  by aggregating metal in the transparent metal oxide layer  21 . 
         [0073]    In other words, the manufacturing method of the array substrate may comprise steps of forming the conductive reflecting structure  1 , the transparent metal oxide layer  21  and the metal particles  211 . Certainly, the transparent metal oxide layer  21  may be first formed on the conductive reflecting structure  1  and then the metal particles  211  are formed on the transparent metal oxide layer  21 , or the metal particles  211  may be first formed on the transparent metal oxide layer  21  and then the transparent metal oxide layer  21  formed thereon with the metal particles  211  is formed on the conductive reflecting structure  1 , as long as the transparent metal oxide layer  21  and the metal particles  211  are finally formed. 
         [0074]    Preferably, for the array substrate having a transparent electrode  22 , the transparent metal oxide layer  21  and the transparent electrode  22  are formed synchronously, and the manufacturing method of the array substrate may specifically comprise following steps S 101  to S 108 . 
         [0075]    S 101 , forming the conductive reflecting structure  1 . 
         [0076]    Specifically, as shown in  FIG. 7 , the conductive reflecting structure  1  is formed above the base substrate  9  by a patterning process and is formed of metal such as molybdenum, niobium, aluminum, copper or alloy thereof, the present embodiment is described by taking the conductive reflecting structure  1  being a data line  3  as an example. Certainly, during manufacturing the data line, a source  31 , a drain  32  or the like structure may also be formed. 
         [0077]    “Patterning process” refers to a process in which a part of a complete material layer is removed so that a particular structure is formed by the remaining material layer, and which comprises one or more steps of forming the material layer, coating photoresist, exposure, developing, etching, stripping off the photoresist and so on. 
         [0078]    Certainly, the manufacturing method of the array substrate may further comprise: a step of, before the step S 101 , forming other well-known structures such as a gate line  51 , a gate  511 , a common electrode line  52 , a gate insulation layer  59  and an active region  6  on the base substrate  9 , the data line  3  as the conductive reflecting structure  1  is formed on the gate insulation layer  59 , which will not be detailed here. 
         [0079]    S 102 , sequentially forming a transparent metal oxide material layer  2  and a photoresist layer  8 . 
         [0080]    Specifically, as shown in  FIG. 8 , a complete transparent metal oxide material layer  2  (for example, an indium tin oxide layer) is deposited on the base substrate  9  subjected to the step S 101 , and then a complete photoresist layer  8  is coated thereon. 
         [0081]    S 103 , performing an exposure process and a developing process on the photoresist layer  8  to retain a photoresist layer  8  with a first thickness in a first region corresponding to the transparent electrode  22 , retain a photoresist layer  8  with a thickness less than the first thickness in a second region corresponding to the conductive reflecting structure  1 , and there is no photoresist layer  8  retained in other regions. 
         [0082]    Specifically, a stepped exposure is performed on the photoresist layer  8  by using a gray scale mask plate so that different regions of the photoresist layer  8  are exposed to different extents, thus, after developing, different regions of the remaining photoresist layer  8  have different thicknesses respectively. Further, the photoresist layer  8  is retained to be thicker in the first region corresponding to the transparent electrode  22  (taking an example of a pixel electrode  4 ) to be formed, and is retained to be thinner in the second region corresponding to the formed conductive reflecting structure  1  (i.e., the data line  3 ), the photoresist layer  8  in other regions are completely removed, so that the structure as shown in  FIG. 9  is obtained. 
         [0083]    S 104 , removing an exposed transparent metal oxide material layer  2  to form the transparent electrode  22  and the transparent metal oxide layer  21 . 
         [0084]    Specifically, as shown in  FIG. 10 , the transparent metal oxide material layer  2  not covered by the photoresist layer  8  is removed by etching or the like ways in the step S 104  so that the gate insulation layer  59  is exposed, by contrast, the transparent metal oxide material layer  2  covered by the photoresist layer  8  is retained to form the transparent electrode  22  (i.e., the pixel electrode  4 ) and the transparent metal oxide layer  21  located on the conductive reflecting structure  1  (i.e., the data line  3 ) respectively. 
         [0085]    S 105 , removing the photoresist layer  8  in the second region, and thinning the photoresist layer  8  in the first region but retaining a certain thickness thereof simultaneously. 
         [0086]    Specifically, as shown in  FIG. 11 , the photoresist layer  8  on the transparent metal oxide layer  21  is removed by an ashing process, and simultaneously the photoresist layer  8  on the transparent electrode  22  (i.e., the pixel electrode  4 ) is thinned. Since the photoresist layer in the second region is thinner than the photoresist layer in the first region, while the photoresist layer in the second region is removed by the ashing process, the photoresist layer in the first region is thinned but still has a certain thickness. 
         [0087]    S 106 , aggregating metal in the exposed transparent metal oxide layer  21  to form the metal particles  211  on the surface of the transparent metal oxide layer  21 . 
         [0088]    Specifically, a process is performed on the exposed transparent metal oxide layer  21  in the second region to aggregate metal in the exposed transparent metal oxide layer  21  so that the metal particles  211  are formed on the surface of the transparent metal oxide layer  21 . Since there is still a certain thickness of photoresist layer  8  covering the transparent electrode  22 , the surface of the transparent electrode  22  will not formed with the metal particles  211  thereon. 
         [0089]    Preferably, the step  106  may specifically comprise: using silane as operating gas, performing a plasma process on the transparent metal oxide layer  211 , and further preferably, operating parameters of the plasma process may include silane flow rate of 200˜800 sccm, gas pressure of 1400˜2000 mtorr, plasma power of 1000˜1600 W. 
         [0090]    In the present embodiment, the specific operating parameters of the plasma process performed on the transparent metal oxide layer  21  include silane flow rate: 200 sccm, gas pressure: 1700 mtorr, plasma power: 1300 W. 
         [0091]    In other words, as shown in  FIG. 12 , silane (i.e., SiH 4 ) may be used as operating gas to excite plasma, and the transparent metal oxide layer  21  (e.g., indium tin oxide layer) is processed by using plasma so that the metal (e.g., indium) therein is aggregated to form the metal particles  211  (e.g., indium particles) as shown in  FIGS. 3 and 4 , thereby diffuse reflection of incident light occurs on the surfaces of the metal particles  211 . After studying, it is found that the metal particles  211  may be formed in appropriate size, quantity or the like by using the above operating parameters, thus the above operating parameters are preferable. 
         [0092]    S 107 , removing the remaining photoresist layer  8  in the first region. 
         [0093]    Specifically, the remaining photoresist layer  8  on the transparent electrode  22  (i.e., the pixel electrode  4 ) is removed so that the transparent electrode  22  (i.e., the pixel electrode  4 ) is exposed, and the structure as shown in  FIGS. 5 and 6  are obtained, wherein in order to clearly indicate the structures such as the gate line  51 , the gate insulation layer  59  is not shown in  FIG. 5 . 
         [0094]    S 108 , optionally, continuing to form other structures such as an interlayer dielectric (ILD) layer, a common electrode (not shown in the figures) or the like to complete the manufacturing of the array substrate. 
         [0095]    In other words, in accordance with the specific structure of the required array substrate, other required structures such as a common electrode may be continuously formed by a patterning process, so that a complete array substrate is finally formed. 
         [0096]    It should be understood that, the above specific manufacturing process flow is not intended to limit the protection scope of the present invention, various well-known modifications thereof may be made by persons skilled in the art. For example, an active layer may be formed first and then the gate line  51  and the gate  511  are manufactured, that is, the thin film transistor may be of a top gate structure; again, there may be only the pixel electrode  4  but no common electrode in the array substrate; again, the common electrode may be first manufactured an then the pixel electrode  4  is manufactured; again, the transparent metal oxide layer  21  and the common electrode may be formed synchronously; again, the conductive reflecting structure  1  may also be other structures such as the gate line  51 ; again, other layers may be provided between the transparent metal oxide layer  21  and the conductive reflecting structure  1 ; again, the array substrate may be applied in an organic light emitting diode display panel, and it may comprise other structures such as an anode, a cathode, an organic light emitting layer and so on. 
         [0097]    The present embodiment also provides a display panel comprising the above array substrate and an opposite substrate (e.g., a color filter substrate) which are aligned and assembled with each other, and there is no black matrix at the position of the display panel corresponding to the conductive reflecting structure  1 . 
         [0098]    In other words, the display panel comprises the above array substrate, and there is no black matrix provided at the position of the display panel corresponding to the conductive reflecting structure  1  (e.g., the data line  3 ), that is, the display panel is a BM-less display panel. 
       Second Embodiment 
       [0099]    The present embodiment provides a display device comprising the display panel of the first embodiment. 
         [0100]    Specifically, the display device may be any product or member having display function, such as a liquid crystal display panel, an electronic paper, an OLED panel, a mobile phone, a tablet computer, a television, a display, a notebook computer, a digital photo frame, a navigator or the like. 
         [0101]    It should be understood that, the foregoing implementations are merely exemplary implementations for explaining the principle of the present invention, but the present invention is not limited thereto. Persons skilled in the art can make various variations and improvements without departing from the spirit and scope of the present invention, and these variations and improvements also fall within the protection scope of the present invention.