Abstract:
A light-emitting diode transfer includes: a stage; a moving portion disposed on the stage and which performs a linear motion on the stage; a linear driving portion disposed on the moving portion and which performs a linear motion on the moving portion; and a head portion rotatably disposed on the linear driving portion and which picks up a light-emitting diode.

Description:
[0001]    This application claims priority to Korean Patent Application No. 10-2015-0123202, filed on Aug. 31, 2015, and all the benefits accruing therefrom under 35 U.S.C. §119, the content of which in its entirety is herein incorporated by reference. 
       BACKGROUND 
       [0002]    1. Field 
         [0003]    One or more exemplary embodiments relate to an apparatus, and more particularly, to a light-emitting diode transfer and a transferring method of light-emitting diode. 
         [0004]    2. Description of the Related Art 
         [0005]    A light-emitting diode (“LED”) is a semiconductor device in which holes and electrons are injected when a forward voltage is applied to a PN-junction diode, and energy generated by recombination of the holes and the electrons is converted to light energy. 
         [0006]    An inorganic LED that emits light using an inorganic compound has been widely used in a backlight of a liquid crystal display (“LCD”) television (“TV”), an electric light, an electronic display board, etc., and an organic LED that emits light by using an organic compound has been used in a miniature electronic apparatus such as a mobile phone, and a large-scale TV, recently. 
       SUMMARY 
       [0007]    A conventional light-emitting diode transfer typically has low productivity with long manufacturing times. 
         [0008]    One or more exemplary embodiments include a light-emitting diode transfer with improved production efficiency. 
         [0009]    According to one or more exemplary embodiments, a light-emitting diode transfer includes: a stage; a moving portion disposed on the stage and which performs a linear motion on the stage; a second linear driving portion installed on the moving portion and which performs a linear motion on the moving portion; and a head portion rotatably disposed on the second linear driving portion and which picks up a light-emitting diode. 
         [0010]    In an exemplary embodiment, the head portion may include: a head body portion rotatably connected to the second linear driving portion; and a pick-up portion connected to the head body portion and picking up the light-emitting diode. 
         [0011]    In an exemplary embodiment, the head body portion may have a polygonal or circular cross-section in a direction perpendicular to a length direction of the head body portion. 
         [0012]    In an exemplary embodiment, the pick-up portion may include a plurality of pick-up portions, and the pick-up portions may be spaced apart from each other along a circumference of the cross-section. 
         [0013]    In an exemplary embodiment, the pick-up portion may include a plurality of pick-up portions, and the pick-up portions may be spaced apart from each other in a length direction of the head body portion. 
         [0014]    In an exemplary embodiment, the head portion may further include: a rotation driving portion connected to at least one of the head body portion and the second linear driving portion, where the rotation driving portion rotates the head body portion. 
         [0015]    In an exemplary embodiment, the second linear driving portion may include: a position variation portion connected to the moving portion; and a fixing bracket which is connected to the position variation portion and to which the head body portion is rotatably connected. 
         [0016]    In an exemplary embodiment, the fixing bracket may be rotatable around a load applied direction which is a rotational axis thereof. 
         [0017]    In an exemplary embodiment, the head body portion may be connected to the second linear driving portion in a way such that the head body portion is rotatable around a length direction of the head body portion which is a rotational axis thereof. 
         [0018]    In an exemplary embodiment, the head portion may be connected to the second linear driving portion in a way such that the head portion is rotatable around a load applied direction. 
         [0019]    In an exemplary embodiment, the head portion may include a plurality of head portions connected to the moving portion, and the head portions may be spaced apart from each other. 
         [0020]    In an exemplary embodiment, the light-emitting diode transfer may further include: another linear driving portion connected to the moving portion and which allows the motion portion to perform the linear motion on the stage. 
         [0021]    In an exemplary embodiment, the light-emitting diode may have a micrometer size. 
         [0022]    In an exemplary embodiment, the light-emitting diode transfer may further include: a chamber which accommodates the stage, the moving portion, the second linear driving portion and the head portion therein. 
         [0023]    According to one or more exemplary embodiments, a transferring method of a light-emitting diode include: seating a first substrate above a support; attaching a plurality of light-emitting diodes disposed above the first substrate to a head portion while rotating the head portion; disposing the head portion above a second substrate by allowing the head portion to perform a linear motion; and transferring a portion of the plurality of light-emitting diodes from the first substrate to the second substrate while rotating the head portion. 
         [0024]    In an exemplary embodiment, the transferring of the portion of the plurality of light-emitting diodes from the first substrate to the second substrate while rotating the head portion may include: allowing the head portion to perform a linear motion. 
         [0025]    In an exemplary embodiment, the transferring of the light-emitting diode may be performed under a vacuum state. 
         [0026]    In an exemplary embodiment, the method may further include aligning the head portion with the first substrate. 
         [0027]    In an exemplary embodiment, the method may further include aligning the head portion with the second substrate. 
         [0028]    In an exemplary embodiment, the first substrate may include a base substrate or a carrier substrate, and the second substrate may include the carrier substrate or a display substrate. 
         [0029]    Such an embodiment may be embodied by using a system, a method, a computer program, or a certain combination of a system, a method and a computer program. 
         [0030]    In exemplary embodiment as set forth herein, a light-emitting diode transfer may increase productivity by simultaneously transferring a plurality of light-emitting diodes. In such an embodiment, a light-emitting diode transfer may reduce a consumed time by sequentially picking up and transferring a plurality of light-emitting diodes. 
         [0031]    Such an embodiment of a light-emitting diode transfer may pick up light-emitting diodes of various shapes and dispose the picked-up light-emitting diodes at various locations. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0032]    These and/or other features will become apparent and more readily appreciated from the following description of the exemplary embodiments, taken in conjunction with the accompanying drawings, in which: 
           [0033]      FIG. 1  is a front cross-sectional view illustrating a light-emitting diode (“LED”) transfer according to an exemplary embodiment; 
           [0034]      FIG. 2  is a side cross-sectional view illustrating the LED transfer illustrated in  FIG. 1 , 
           [0035]      FIG. 3  is a cross-sectional view illustrating a linear driving portion of an LED transfer illustrated in  FIG. 2 ; 
           [0036]      FIG. 4  is a perspective view illustrating a head portion illustrated in  FIG. 2 ; 
           [0037]      FIG. 5  is a cross-sectional view taken along line IV-IV of  FIG. 3 ; 
           [0038]      FIG. 6  is a cross-sectional view taken along line V-V of  FIG. 3 ; 
           [0039]      FIG. 7  is a side view illustrating a head portion illustrated in  FIG. 2  according to an exemplary embodiment; 
           [0040]      FIG. 8  is a side view illustrating a head portion illustrated in  FIG. 2  according to an alternative exemplary embodiment; 
           [0041]      FIG. 9  is a side view illustrating a head portion illustrated in  FIG. 2  according to another alternative exemplary embodiment; 
           [0042]      FIG. 10  is a side view illustrating a head portion illustrated in  FIG. 2  according to still another alternative exemplary embodiment; 
           [0043]      FIG. 11  is a side view illustrating the arrangement of a head portion illustrated in  FIG. 2  according to an exemplary embodiment; 
           [0044]      FIG. 12  is a view illustrating an exemplary embodiment of a process of manufacturing an organic light-emitting display device by using an LED transfer illustrated in  FIG. 1 ; 
           [0045]      FIG. 13  is a schematic plan view illustrating a display device manufactured by an exemplary embodiment of a manufacturing process illustrated in  FIG. 12 ; 
           [0046]      FIG. 14  is a schematic cross-sectional view illustrating a display device of  FIG. 13  taken along line A-A according to an exemplary embodiment; 
           [0047]      FIG. 15  is a side cross-sectional view illustrating an LED transfer according to another alternative exemplary embodiment; 
           [0048]      FIG. 16  is a cross-sectional view illustrating a first linear driving portion of an LED transfer illustrated in  FIG. 15 ; 
           [0049]      FIG. 17  is a schematic plan view illustrating the arrangement of an LED transferred from a first substrate to a second substrate via an LED transfer illustrated in  FIG. 15 ; 
           [0050]      FIG. 18  is a side cross-sectional view illustrating an LED transfer according to another alternative exemplary embodiment; and 
           [0051]      FIG. 19  is a cross-sectional view illustrating a first linear driving portion of an LED transfer illustrated in  FIG. 18 . 
       
    
    
     DETAILED DESCRIPTION 
       [0052]    The invention now will be described more fully hereinafter with reference to the accompanying drawings, in which various embodiments are shown. This invention may, however, be embodied in many different forms, and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like reference numerals refer to like elements throughout. 
         [0053]    It will be understood that when an element is referred to as being “on” another element, it can be directly on the other element or intervening elements may be present therebetween. In contrast, when an element is referred to as being “directly on” another element, there are no intervening elements present. 
         [0054]    It will be understood that, although the terms “first,” “second,” “third” etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, “a first element,” “component,” “region,” “layer” or “section” discussed below could be termed a second element, component, region, layer or section without departing from the teachings herein. 
         [0055]    Expressions such as “at least one of” when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list. 
         [0056]    The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms, including “at least one,” unless the content clearly indicates otherwise. “Or” means “and/or.” As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. It will be further understood that the terms “comprises” and/or “comprising,” or “includes” and/or “including” when used in this specification, specify the presence of stated features, regions, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components, and/or groups thereof. 
         [0057]    Furthermore, relative terms, such as “lower” or “bottom” and “upper” or “top,” may be used herein to describe one element&#39;s relationship to another element as illustrated in the Figures. It will be understood that relative terms are intended to encompass different orientations of the device in addition to the orientation depicted in the Figures. For example, if the device in one of the figures is turned over, elements described as being on the “lower” side of other elements would then be oriented on “upper” sides of the other elements. The exemplary term “lower,” can therefore, encompasses both an orientation of “lower” and “upper,” depending on the particular orientation of the figure. Similarly, if the device in one of the figures is turned over, elements described as “below” or “beneath” other elements would then be oriented “above” the other elements. The exemplary terms “below” or “beneath” can, therefore, encompass both an orientation of above and below. 
         [0058]    Exemplary embodiments are described herein with reference to cross section illustrations that are schematic illustrations of idealized embodiments. As such, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Thus, embodiments described herein should not be construed as limited to the particular shapes of regions as illustrated herein but are to include deviations in shapes that result, for example, from manufacturing. For example, a region illustrated or described as flat may, typically, have rough and/or nonlinear features. Moreover, sharp angles that are illustrated may be rounded. Thus, the regions illustrated in the figures are schematic in nature and their shapes are not intended to illustrate the precise shape of a region and are not intended to limit the scope of the present claims. 
         [0059]    Herein, the x-axis, the y-axis and the z-axis are not limited to three axes of the rectangular coordinate system, and may be interpreted in a broader sense. For example, the x-axis, the y-axis, and the z-axis may be perpendicular to one another, or may represent different directions that are not perpendicular to one another. 
         [0060]    When a certain embodiment may be implemented differently, a specific process order may be performed differently from the described order. For example, two consecutively described processes may be performed substantially at the same time or performed in an order opposite to the described order. 
         [0061]    Hereinafter, exemplary embodiments of the invention will be described with reference to the drawings. 
         [0062]      FIG. 1  is a front cross-sectional view illustrating a light-emitting diode (“LED”) transfer  100  according to an exemplary embodiment.  FIG. 2  is a side cross-sectional view illustrating the LED transfer  100  illustrated in  FIG. 1 .  FIG. 3  is a cross-sectional view illustrating a linear driving portion of an LED transfer illustrated in  FIG. 2 . 
         [0063]    Referring to  FIGS. 1 to 3 , an exemplary embodiment of the LED transfer  100  may include a chamber  110 , a stage  120 , a moving portion  130 , a first linear driving portion  140 , a second linear driving portion  150 , a head portion  160 , a vision portion  170 , and a pressure adjustor  180 . Herein, the LED transfer means an LED transfer apparatus or an apparatus that transfers an LED from one place to another, e.g., transfers an LED on a surface of a substrate to a surface of another substrate. 
         [0064]    In such an embodiment, the chamber  110  may define a space in an inside thereof and an open portion may be defined in the chamber  110 . In such an embodiment, a gate valve  111  may be disposed in or installed to the open portion of the chamber  110  and open/close the open portion. 
         [0065]    The chamber  110  may have various inner pressures. In one exemplary embodiment, for example, the chamber  110  may have an inner pressure that is same as or similar to atmospheric pressure while a process to be described below is performed inside the chamber  110 . In such an embodiment, the pressure adjuster  180  may be omitted. 
         [0066]    According to another exemplary embodiment, the chamber  110  may have an inner pressure that is same as or similar to vacuum while a process to be described below is performed inside the chamber  110 . In such an embodiment, the pressure adjuster  180  may be connected to the chamber  110  and adjust the inner pressure of the chamber  110 . In such an embodiment, when the gate valve  111  is open, the pressure adjuster  180  may maintain the inner pressure of the chamber  110  same as or similar to atmospheric pressure. In such an embodiment, while a process to be described below is performed inside the chamber  110 , the gate valve  111  may be closed and the pressure adjuster  180  may maintain the inner pressure of the chamber  110  same as or similar to vacuum. 
         [0067]    For convenience of description, an exemplary embodiment where the pressure adjustor  180  is connected to the chamber  110  and the inner pressure of the chamber  110  changes from atmospheric pressure to vacuum will hereinafter be mainly described. 
         [0068]    The stage  120  may be fixed inside the chamber  110 . In one exemplary embodiment, for example, the stage  120  may be fixed to an inner wall surface of the chamber  110 . According to another exemplary embodiment, the stage  120  may be supported by a separate support frame  121  connected to and vertically extending from the lower surface of the chamber  110 . For convenience of description, an exemplary embodiment where the stage  120  is supported by a support frame  121  will hereinafter be mainly described. 
         [0069]    In an exemplary embodiment, the stage  120  may be in a plate shape. In such an embodiment, a second substrate  200  and a first substrate  1  may be disposed or seated on a side or surface (e.g., an upper side or surface) of the stage  120 . In such an embodiment, a recess, into which the second substrate  200  and the first substrate  1  are inserted, may be defined or formed in a side of the stage  120 . According to an alternative exemplary embodiment, a side of the stage  120  may be flat and the second substrate  200  and the first substrate  1  may be seated on the stage  120 . According to another alternative exemplary embodiment, the stage  120  may have a protrusion (not shown) protruding from a side of the stage  120 , and the protrusion may maintain or limit the positions of the second substrate  200  and the first substrate  1  by contacting the outer surfaces of the second substrate  200  and the first substrate  1 . 
         [0070]    In this case, the first substrate  1  may include one of a base substrate and a carrier substrate. Also, the second substrate  200  may include one of the carrier substrate and a display substrate. 
         [0071]    A plurality of LEDs may be manufactured and disposed above the base substrate. In this case, the plurality of LEDs may be spaced apart from each other above the base substrate. Also, the plurality of LEDs disposed above the base substrate may be transferred and disposed above the carrier substrate. The position of the plurality of LEDs is temporarily attached to or fixed on the carrier substrate by using an adhesive layer, etc. The plurality of LEDs may be transferred from one of the base substrate or the carrier substrate to one of the carrier substrate or the second substrate  200 . In an exemplary embodiment, the plurality of LEDs may be separated from one of the base substrate or the carrier substrate by using a known physical or chemical method. According to an exemplary embodiment, the plurality of LEDs may be separated from one of the base substrate or the carrier substrate by using a laser lift off (“LLO”) method. According to another exemplary embodiment, after the plurality of LEDs is formed on the first substrate  1 , the plurality of LEDs may be directly transferred to the second substrate  200 . 
         [0072]    Hereinafter, for convenience of description, a case where the first substrate  1  includes a transfer substrate, and the second substrate  200  includes a display substrate is mainly described. 
         [0073]    The moving portion  130  may be coupled to the stage  120  and may slide on the stage  120 . In an exemplary embodiment, the moving portion  130  may be connected or installed to a lateral portion of a surface of the stage  120  and linearly move on the stage  120 . 
         [0074]    The first linear driving portion  140  may be connected with at least one of the stage  120  and the moving portion  130  to allow the moving portion  130  to linearly move. In such an embodiment, the first linear driving portion  140  may be in various shapes, which will be described later in greater detail. 
         [0075]    The second linear driving portion  150  may include a position variation portion  151  connected or installed to the moving portion  130  and a fixing bracket  152  connected or installed to the position variation portion  151 . In an exemplary embodiment, the position variation portion  151  may be fixed to the moving portion  130  and change the position of the head portion  160 . In such an embodiment, the position variation portion  151  may allow the head portion  160  to perform a linear motion with respect to the moving portion  130 . In one exemplary embodiment, for example, the position variation portion  151  may allow the head portion  160  to perform a linear motion in a load applied direction (or a z-axis direction of  FIG. 1 ). 
         [0076]    In an exemplary embodiment, the position variation portion  151  may be similar to the first linear driving portion  140 . The position variation portion  151  may be in various shapes. In one exemplary embodiment, for example, the position variation portion  151  may include a cylinder including a shaft of which position is variable. According to an alternative exemplary embodiment, the position variation portion  151  may include a magnetic levitation driving portion formed in a magnetic levitation manner. According to another alternative exemplary embodiment, the position variation portion  151  may include a linear motor connected between the head portion  160  and the moving portion  130 . According to another alternative exemplary embodiment, the position variation portion  151  may include a motor connected or installed to the moving portion  130 , a first gear unit connected to the motor, and a second gear unit connected to the first gear unit. In such an embodiment, the position variation portion  151  is not limited thereto, and may include any unit or structure that may allow the head portion  160  to perform a linear motion or to move linearly. However, for convenience of description, an exemplary embodiment where the position variation portion  151  includes a cylinder (not shown) will hereinafter be mainly described. 
         [0077]    A portion of the fixing bracket  152  may be bent, and the bent portion of the fixing bracket  152  may be connected with the head portion  160 . 
         [0078]    The head portion  160  may be disposed on or installed to the moving portion  130  in a way such that the head portion  160  may perform a linear motion with respect to the moving portion  130 . In such an embodiment, the head portion  160  may perform a linear motion in a load applied direction with respect to the moving portion  130 . The head portion  160  will be described later in greater detail. 
         [0079]    The vision portion  170  may be installed at various positions. In one exemplary embodiment, for example, the vision portion  170  may be installed to pass through the inner wall of the chamber  110 . According to an alternative exemplary embodiment, the vision portion  170  may be connected or installed to the moving portion  130 . According to another alternative exemplary embodiment, the vision portion  170  may be disposed or installed inside the chamber  110 . However, for convenience of description, an exemplary embodiment where the vision portion  170  is connected or installed to the moving portion  130  will hereinafter be mainly described. 
         [0080]    The vision portion  170  may be in various shapes. In one exemplary embodiment, for example, the vision portion  170  may include a high resolution camera. According to an alternative exemplary embodiment, the vision portion  170  may include a charge-coupled device (“CCD”) camera. 
         [0081]    The vision portion  170  may capture a position of at least one of the head portion  160 , the first substrate  1 , and the second substrate  200 . In an exemplary embodiment, the position of the head portion  160  may be adjusted based on an image captured by the vision portion  170 . 
         [0082]    The pressure adjustor  180  may include a connection pipe  181  connected to the chamber  110 , and a pump  182  connected or installed to the connection pipe  181 . In an exemplary embodiment, a gas inside the connection pipe  181  flows depending on an operation of the pump  182 , such that the inner pressure of the chamber  110  may be adjusted. 
         [0083]    Hereinafter, the first linear driving portion  140  and the head portion  160  will be described in greater detail with reference to  FIG. 3 . 
         [0084]    Referring to  FIG. 3 , the first linear driving portion  140  may include various devices and structures. In one exemplary embodiment, for example, the first linear driving portion  140  may include a cylinder. According to an alternative exemplary embodiment, the first linear driving portion  140  may include a linear motor. According to another alternative exemplary embodiment, the first linear driving portion  140  may include a motor and a ball screw connected with the motor. According to another alternative exemplary embodiment, the first linear driving portion  140  may operate in a magnetic levitation structure. According to another alternative exemplary embodiment, the first linear driving portion  140  may include a motor and a gear unit connected with the motor. However, the first linear driving portion  140  is not limited thereto and may include any device or structure installed between the moving portion  130  and the stage  120  to allow the moving portion  130  to perform a linear motion in a predetermined direction of the stage  120 . Hereinafter, an exemplary embodiment where the first linear driving portion  140  operates in a magnetic levitation structure will be mainly described for convenience of description. 
         [0085]    In an exemplary embodiment, an end of the moving portion  130  may be disposed in or inserted into the stage  120 . According to an alternative exemplary embodiment, a portion of the stage  120  may protrude and may be inserted into the end of the moving portion  130 . However, for convenience of description, an exemplary embodiment where the end of the moving portion  130  is inserted into the stage  120  will hereinafter be mainly described. 
         [0086]    In such an embodiment, the first linear driving portion  140  may be installed between the moving portion  130  and the stage  120  as described above. In an exemplary embodiment, the first linear driving portion  140  may include an interval adjustor  141  disposed between the moving portion  130  and the stage  120 . In such an embodiment, the first linear driving portion  140  may include a force-applying portion  142  disposed between the moving portion  130  and the stage  120 . 
         [0087]    The interval adjustor  141  may allow the moving portion  130  to be spaced from the stage  120  by using electromagnetic force. In an exemplary embodiment, the interval adjustor  141  may include a first interval adjustor  141 - 1  and a second interval adjustor  141 - 2  disposed to face each other between the moving portion  130  and the stage  120 . 
         [0088]    In an exemplary embodiment, one of the first interval adjustor  141 - 1  and the second interval adjustor  141 - 2  may be disposed on or installed to one of the moving portion  130  and the stage  120 . In such an embodiment, the other of the first interval adjustor  141 - 1  and the second interval adjustor  141 - 2  may be disposed on or installed to the other of the moving portion  130  and the stage  120 . For convenience of description, an exemplary embodiment where the first interval adjustor  141 - 1  is installed to the moving portion  130 , and the second interval adjustor  141 - 2  is installed to the stage  120  will hereinafter be mainly described. 
         [0089]    In such an embodiment, the first interval adjustor  141 - 1  and the second interval adjustor  141 - 2  may generate magnetic force having the same polarity. In an exemplary embodiment, the first interval adjustor  141 - 1  and the second interval adjustor  141 - 2  may include at least one of a permanent magnet and an electromagnet. 
         [0090]    The first interval adjustor  141 - 1  and the second interval adjustor  141 - 2  may reduce friction between the moving portion  130  and the stage  120  while the moving portion  130  moves by separating the moving portion  130  from the stage  120  or maintaining the moving portion  130  and the stage  120  to be spaced apart from each other. 
         [0091]    The force-applying portion  142  may include a first force-applying portion  142 - 1  and a second force-applying portion  142 - 2  disposed to face each other. In an exemplary embodiment, one of the first force-applying portion  142 - 1  and the second force-applying portion  142 - 2  may be installed to one of the moving portion  130  and the stage  120 . In such an embodiment, one of the first force-applying portion  142 - 1  and the second force-applying portion  142 - 2  may be installed to the other of the moving portion  130  and the stage  120 . For convenience of description, an exemplary embodiment where the first force-applying portion  142 - 1  is installed to the moving portion  130 , and the second force-applying portion  142 - 2  is installed to the stage  120  will hereinafter be mainly described. 
         [0092]    The first force-applying portion  142 - 1  and the second force-applying portion  142 - 2  may include at least one of a permanent magnet and an electromagnet. In an exemplary embodiment, the first force-applying portion  142 - 1  and the second force-applying portion  142 - 2  may be provided in plural in a movement direction (or an x-axis direction of  FIG. 3 ) of the moving portion  130 . The first force-applying portion  142 - 1  and the second force-applying portion  142 - 2  may move the moving portion  130  in a desired direction by generating polarities different from each other. 
         [0093]      FIG. 4  is a perspective view illustrating a head portion  160  illustrated in  FIG. 2 .  FIG. 5  is a cross-sectional view taken along line V-V of  FIG. 4 .  FIG. 6  is a cross-sectional view taken along line VI-VI of  FIG. 4 . 
         [0094]    Referring to  FIGS. 4 to 6 , the head portion  160  may include a head body portion  161 , a rotational driving portion  163 , and a pick-up portion  162 . 
         [0095]    The head body portion  161  may have a three-dimensional shape. In an exemplary embodiment, the head body portion  161  may have various shapes. In one exemplary embodiment, for example, the head body portion  161  may have a polygonal pillar shape or a circular pillar shape. 
         [0096]    The rotational driving portion  163  may be connected with the head body portion  161  and rotate the head body portion  161 . In an exemplary embodiment, the rotational driving portion  163  may be connected or fixed to the fixing bracket  152 . The rotational driving portion  163  may rotate the head body portion  161  around a length direction (a y-axis of  FIG. 4 ) of the head body portion  161  as a rotational axis. 
         [0097]    The rotational driving portion  163  may include a rotational shaft  163 - 2  disposed inside or installed to pass through the head body portion  161 , and a rotational motor  163 - 1  connected to the rotational shaft  163 - 2 . In an exemplary embodiment, a method of connecting the rotational motor  163 - 1  with the rotational shaft  163 - 2  may be various. In one exemplary embodiment, for example, the rotational motor  163 - 1  and the rotational shaft  163 - 2  may be connected with each other by using pulleys respectively installed to the rotational shaft  163 - 2  and the rotational motor  163 - 1 , and a belt connecting the pulleys. According to an alternative exemplary embodiment, gear units may be respectively installed to the rotational motor  163 - 1  and the rotational shaft  163 - 2 , and the gear units may be connected with each other. According to another alternative exemplary embodiment, the rotational motor  163 - 1  and the rotational shaft  163 - 2  may be directly connected with each other. However, for convenience of description, an exemplary embodiment where the rotational motor  163 - 1  and the rotational shaft  163 - 2  are directly connected with each other will hereinafter be mainly described. 
         [0098]    The pick-up portion  162  may separate an LED  230  from the first substrate  1 , and move or transfer the LED  230  to the second substrate  200 . In an exemplary embodiment, the pick-up portion  162  may attach the LED  230  thereon by using electrostatic force or adhesive force. However, the pick-up portion  162  is not limited thereto and may include any unit or structure that allows the LED  230  to be attached thereon. 
         [0099]    The LED  230  may have a fine size. In one exemplary embodiment, for example, the LED  230  may have a micrometer size. 
         [0100]    In an exemplary embodiment, the pick-up portion  162  may be provided in plural. The plurality of pick-up portions  162  may be spaced apart from each other in a length direction (or a y-axis direction of  FIG. 6 ) of the head body portion  161 . In such an embodiment, the plurality of pick-up portions  162  may be spaced apart from each other along a circumference of the cross-section perpendicular to the length direction of the head body portion  161 . In an exemplary embodiment, where the cross-section of the head body portion  161  is a polygon, the pick-up portion  162  may be arranged in a line on each side of the polygon. 
         [0101]      FIG. 7  is a side view illustrating a head portion illustrated in  FIG. 2  according to an exemplary embodiment.  FIG. 8  is a side view illustrating a head portion illustrated in  FIG. 2  according to an alternative exemplary embodiment.  FIG. 9  is a side view illustrating a head portion illustrated in  FIG. 2  according to another alternative exemplary embodiment.  FIG. 10  is a side view illustrating a head portion illustrated in  FIG. 2  according to still another alternative exemplary embodiment. 
         [0102]    Referring to  FIGS. 7 to 10 , the head body portion  161  may have various shapes as described above. In one exemplary embodiment, for example, the head body portion  161  may have a trigonal prism shape. In an exemplary embodiment, a cross-section perpendicular to a length direction of the head body portion  161  may be a triangle as illustrated in  FIG. 7 . In an exemplary embodiment, the pick-up portion  162  may be installed to the head body portion  161  such that the pick-up portions  162  are spaced apart from each other in a length direction of the trigonal prism. The pick-up portions  162  may be arranged such that the plurality of pick-up portions  162  are spaced apart from each other in a line on three sides formed in the length direction of the trigonal prism. 
         [0103]    According to an alternative exemplary embodiment, as illustrated in  FIG. 8 , the head body portion  161  may have a pentagonal pillar shape. In such an embodiment, as described above, the plurality of pick-up portions  162  may be spaced apart from each other on the sides of the head body portion  161 , respectively. 
         [0104]    According to another alternative exemplary embodiment, as illustrated in  FIG. 9 , the head body portion  161  may have a hexagonal pillar shape. In such an embodiment, the pick-up portion  162  may be installed on each side of the head body portion  161 . 
         [0105]    According to another alternative exemplary embodiment, as illustrated in  FIG. 10 , the head body portion  161  may have a circular pillar shape. In such an embodiment, the pick-up portions  162  may be spaced from each other with a constant interval on the surface of the head body portion  161 . 
         [0106]      FIG. 11  is a side view illustrating the arrangement of the head body portion illustrated in  FIG. 2  according to an exemplary embodiment. 
         [0107]    Referring to  FIG. 11 , the head portion  160  and the fixing bracket  152  may be provided in plural. In an exemplary embodiment, the plurality of head portions  160  may be spaced apart from each other on the moving portion  130  (for example, the plurality of head portions  160  may be spaced apart from each other in an x-axis direction of  FIG. 11 ). In such an embodiment, each fixing bracket  152  may be installed to correspond to each head portion  160 . 
         [0108]    In such an embodiment, where the head portion  160  is provided in plural, the head body portions  161  may be connected with one rotational motor  163 - 1  and rotate simultaneously. According to an alternative exemplary embodiment, each rotational motor  163 - 1  may be connected to each head body portion  161  and each of the head body portions  161  may individually rotate or rotate independently of each other. 
         [0109]    Hereinafter, an exemplary embodiment of a process of manufacturing an organic light-emitting display device by using the LED transfer  100  will be described with reference to  FIGS. 12 to 14 . 
         [0110]      FIG. 12  is a view illustrating an exemplary embodiment of a process of manufacturing an organic light-emitting display device by using the LED transfer  100  illustrated in  FIG. 1 .  FIG. 13  is a schematic plan view illustrating a display device  10  manufactured according to a manufacturing process illustrated in  FIG. 12 .  FIG. 14  is a schematic cross-sectional view illustrating a display device of  FIG. 13  taken along line A-A according to an exemplary embodiment. In the following description, like reference numerals denote like elements. 
         [0111]    Referring to  FIGS. 12 to 14 , in an exemplary embodiment, the LED transfer  100  may transfer the LED  230  on the first substrate  1  to the second substrate  200 . In an exemplary embodiment, the first substrate  1 , on which the LED  230  is disposed, may introduced into the chamber  110 , and then the first substrate  1  may be seated on the stage  120 . In such an embodiment, the first substrate  1  may be moved into the chamber  110  via a separate robot arm, a shuttle, etc. provided inside or outside the chamber  110 . 
         [0112]    Similar to the first substrate  1 , the second substrate  200  may be transferred into the chamber  110 . In an exemplary embodiment, the LED transfer  100  may manufacture the display device  10  by transferring the LED  230  of the first substrate  1  onto the second substrate  200 . 
         [0113]    In an exemplary embodiment, the LED transfer  100  may pick up the LED  230  on the first substrate  1 . In such an embodiment, the first linear driving portion  140  may dispose the moving portion  130  on the first substrate  1 . 
         [0114]    The second linear driving portion  150  may dispose the head body portion  161  at a predetermined position on the first substrate  1  by lowering the head portion  160  toward the first substrate  1 . In an exemplary embodiment, the positions of the head body portion  161  and the first substrate  1  may be detected and the position of the head body portion  161  may be changed based on an image captured by the vision portion  170 . In one exemplary embodiment, for example, an alignment mark is provided or formed on the first substrate  1 , and the position of the head body portion  161  may be adjusted by detecting the positions of the head body portion  161  and the first substrate  1  based on an image captured by the vision portion  170  and adjusting the first linear driving portion  140  and the second linear driving portion  150 . According to an alternative exemplary embodiment, the position of the head body portion  161  may be adjusted by capturing an alignment mark on the stage  120 . According to another alternative exemplary embodiment, the position of the head body portion  161  may be adjusted by measuring the shape of the head body portion  161  and the first substrate  1  by using the vision portion  170 . In an exemplary embodiment, a method of adjusting the position of the head body portion  161  by using the vision portion  170  is not limited to the above methods, and may include any method of adjusting the position of the head body portion  161  by detecting the positions of the head body portion  161  and the first substrate  1 . 
         [0115]    When the head body portion  161  is disposed at a predetermined position, the head body portion  161  is lowered by the second linear driving portion  150 , and then the pick-up portion  162  may attach the LED  230  thereon. In an exemplary embodiment, the LEDs  230  may be simultaneously attached on the plurality of pick-up portions  162  arranged in a length direction of the head body portion  161 . 
         [0116]    The second linear driving portion  150  may raise the head body portion  161 , and the rotational driving portion  163  may operate to rotate the head body portion  161  by a predetermined angle. Due to rotation of the head body portion  161 , the pick-up portion  162  not being attached the LED  230  thereon may be disposed to face the first substrate  1  again. 
         [0117]    When the above process is completed, the first linear driving portion  140  may operate and dispose the head portion  161  above the LED above the base substrate  1 . In this case, the second linear driving portion  150  may operate as described above. 
         [0118]    When the first linear driving portion  140  and the second linear driving portion  150  operate again, the head body portion  161  may descend and the pick-up portion  162  may attach the LED  230  thereon. This operation may be repeatedly performed until the LEDs  230  are respectively attached on all of the pick-up portions  162  of the head portion  160 . 
         [0119]    When the LEDs  230  are respectively attached on all of the pick-up portions  162  of the head body portion  161 , the first linear driving portion  140  may operate and move the moving portion  130  from the first substrate  1  to the second substrate  200  (an x-axis direction of  FIG. 12 ). In an exemplary embodiment, the vision portion  170  captures the positions of the second substrate  200  and the head body portion  161 , and the position of the head body portion  161  may be adjusted based on the captured result. The method of adjusting the position of the head body portion  161  is substantially the same as such a method described above, and any repetitive detailed description thereof will be omitted. 
         [0120]    When the position of the head body portion  161  reaches a predetermined position, the second linear driving portion  150  may operate and lower the head body portion  161  to transfer the LED  230  to the second substrate  200 . 
         [0121]    In an exemplary embodiment, when the second linear driving portion  150  operates, the LEDs  230  respectively attached on the plurality of pick-up portions  162  linearly arranged on a side of the head body portion  161  may be transferred to the second substrate  200 . In such an embodiment, when the second linear driving portion  150  operates reversely and raises the head body portion  161 , the rotational driving portion  163  may operate to allow the pick-up portions  162  arranged in a line on another side of the head body portion  161  to face the second substrate  200 . In an exemplary embodiment, the first linear driving portion  140  may move the moving portion  130  by a small amount in an x-axis direction of  FIG. 12 . The second linear driving portion  150  may lower the head body portion  161  and transfer the LEDs  230  of the pick-up portions  162  linearly arranged on another side of the head body portion  161  to the second substrate  200 . This operation may be repeatedly performed until the LEDs  230  of all of the pick-up portions  162  are transferred to the second substrate  200 . 
         [0122]    When the transferring of the LEDs  230  of all of the pick-up portions  162  of the head body portion  161  is completed, the first linear driving portion  140  may dispose the moving portion  130  to the first substrate  1  and repeatedly perform the above operation. 
         [0123]    When the above operation is completed, the second substrate  200 , to which the LEDs  230  have been transferred, is transferred to the outside and the display device  10  may be manufactured by performing the next process. 
         [0124]    The above manufactured display device  10  may include the second substrate  200  and an emission layer  210  on the second substrate  200 . 
         [0125]    In an exemplary embodiment, the second substrate  200  may include a substrate  201 , a thin film transistor (“TFT”) on the substrate  201 , and a planarization layer  205  on the TFT. A first electrode  211  connected with the TFT through a via hole may be provided or formed on the planarization layer  205 . In such an embodiment, the second substrate  200  may include a bank layer  206  disposed to cover a portion of the first electrode  211 . 
         [0126]    A display area DA and a non-display area outside the display area DA may be defined on the substrate  201 . The emission layer  210  may be disposed in the display area DA, and a power line (not shown) etc. may be disposed in the non-display area. In such an embodiment, a pad portion  250  may be provided or disposed in the non-display area. 
         [0127]    The substrate  201  may include various materials. In one exemplary embodiment, for example, the substrate  201  may include a transparent glass material having SiO 2  as a primary component. However, the substrate  201  is not limited thereto and may include a transparent plastic material and thus be flexible. The plastic material may include at least one insulating organic material selected from polyether sulfone (“PES”), polyacrylate (“PAR”), polyetherimide (“PEI”), polyethylene naphthalate (“PEN”), polyethylene terephthalate (“PET”), polyphenylene sulfide (“PPS”), polyacrylate (“PAR”), polyimide, polycarbonate (“PC”), cellulose triacetate (“TAC”) and cellulose acetate propionate (“CAP”). 
         [0128]    In an exemplary embodiment, where the substrate  201  is a substrate for a bottom-emission type display device that produces an image in a direction of the substrate  201 , the substrate  201  may include a transparent material. In an alternative exemplary embodiment, where the substrate  201  is a substrate for a top-emission type display device that produces an image in an opposite direction of the substrate  201 , the substrate  201  may not only include a transparent material. In an exemplary embodiment, the substrate  201  may include a metal. 
         [0129]    In an exemplary embodiment, where the substrate  201  includes a metal, the substrate  201  may include at least one selected from F, Cr, Mn, Ni, Ti, Mo, steel use stainless (“SUS”), Invar alloy, Inconel alloy, and Kovar alloy, but is not limited thereto. 
         [0130]    A buffer layer  202  may be provided or formed on the substrate  201 . The buffer layer  202  may provide a planarized surface above the substrate  201 , and effectively prevent penetration of foreign substances or moisture via the substrate  201 . In one exemplary embodiment, for example, the buffer layer  202  may include an inorganic material such as a silicon oxide, a silicon nitride, a silicon oxynitride, an aluminum oxide, an aluminum nitride, a titanium oxide or a titanium nitride, or an organic material such as polyimide, polyester and acryl, for example. The buffer layer  202  may have a multi-layer structure, in which each layer may include at least one of the materials above. 
         [0131]    The TFT may include an active layer  207 , a gate electrode  208 , a source electrode  209   a , and a drain electrode  209   b.    
         [0132]    An exemplary embodiment where the TFT is a top gate-type TFT, in which the active layer  207 , the gate electrode  208 , the source electrode  209   a  and the drain electrode  209   b  are sequentially formed, will hereinafter be described, but exemplary embodiments are not limited thereto and various types of TFTs such as a bottom gate-type TFT may be adopted. 
         [0133]    In such an embodiment, the active layer  207  may include a semiconductor material, for example, amorphous silicon or poly crystalline silicon. However, exemplary embodiment is not limited thereto and the active layer  207  may include various materials. According to an exemplary embodiment, the active layer  207  may include an organic semiconductor material. 
         [0134]    According to an alternative exemplary embodiment, the active layer  207  may include an oxide semiconductor material. In one exemplary embodiment, for example, the active layer  207  may include Groups 12, 13, and 14 metallic elements such as Zn, In, Ga, Sn, Cd, Ge, and an oxide of a combination thereof. 
         [0135]    A gate insulating layer  203  is provided or formed on the active layer  207 . The gate insulating layer  203  insulates the gate electrode  208  from the active layer  207 . The gate insulating layer  203  may include a single layer or a plurality of layers including an inorganic material such as a silicon oxide and/or a silicon nitride. 
         [0136]    The gate electrode  208  is provided or formed above the gate insulating layer  203 . The gate electrode  208  may be connected with a gate line (not shown) that applies an on/off-signal to the TFT. 
         [0137]    The gate electrode  208  may include a low resistance metallic material. The gate electrode  208  may include a single layer or layers including at least one of Al, Pt, Pd, Ag, Mg, Au, Ni, Nd, Ir, Cr, Li, Ca, Mo, Ti, W, and Cu by taking into account adhesion with an adjacent layer, a surface planarization characteristic of a stacked layer, a processing characteristic, etc. 
         [0138]    An interlayer insulating layer  204  is provided or formed on the gate electrode  208 . The interlayer insulating layer  204  insulates the source electrode  209   a  and the drain electrode  209   b  from the gate electrode  208 . The interlayer insulating layer  204  may include a single layer or a plurality of layers including an inorganic material. In an exemplary embodiment, the inorganic material may be a metallic oxide or a metallic nitride. In one exemplary embodiment, for example, the inorganic material may include a silicon oxide (SiO 2 ), a silicon nitride (SiNx), a silicon oxynitride (SiON), an aluminum oxide (Al 2 O 3 ), a titanium oxide (TiO 2 ), a tantalum oxide (Ta 2 O 5 ), a hafnium oxide (HfO 2 ), a zinc oxide (ZnO 2 ), etc. 
         [0139]    The source electrode  209   a  and the drain electrode  209   b  are formed on the interlayer insulating layer  204 . The source electrode  209   a  and the drain electrode  209   b  may include a single layer or layers including at least one of Al, Pt, Pd, Ag, Mg, Au, Ni, Nd, Ir, Cr, Li, Ca, Mo, Ti, W, and Cu. The source electrode  209   a  and the drain electrode  209   b  contact regions of the active layer  207 . 
         [0140]    The planarization layer  205  is formed on the TFT. The planarization layer  205  covers the TFT to resolve a step difference caused by the TFT and thereby prevents a formation of a defective emission layer  210  due to lower irregularities by planarizing the upper surface of the TFT. 
         [0141]    The planarization layer  205  may include a single layer or layers including an organic material. The organic material may include a general polymer such as polymethyl methacrylate (“PMMA”) or polystylene (“PS”), polymer derivatives having a phenol-based group, an acryl-based polymer, an imide-based polymer, an aryl ether-based polymer, an amide-based polymer, a fluorine-based polymer, a p-xylene-based polymer, a vinyl alcohol-based polymer, and a blend thereof. In such an embodiment, the planarization layer  205  may include a composite stacked layer including an inorganic insulating layer and an organic insulating layer. 
         [0142]    The first electrode  211  and the bank layer  206  may be disposed on the planarization layer  205 . 
         [0143]    The first electrode  211  may be electrically connected with the TFT. Specifically, the first electrode  211  may be electrically connected with the drain electrode  209   b  via a contact hole formed in the planarization layer  205 . The first electrode  211  may have various shapes, and for example, may be patterned in an island shape. 
         [0144]    The bank layer  206  may be disposed on the first electrode  211  and the planarization layer  205  and define a pixel region. The bank layer  206  may defined a space in which the LED  230  is disposed. In an exemplary embodiment, the bank layer  206  may include a thermoplastic resin such as polycarbonate (PC), polyethylene terephthalate (PET), polyether sulfone (PES), polyvinyl butyral (PVB), polyphenylene ether (PPE), polyamide, polyetherimide (PEI), a norbornene-based resin, a methacrylic resin, a cyclic polyolefin-based resin, etc., a thermosetting resin such as an epoxy resin, a phenolic resin, a urethane resin, an acrylic resin, a vinyl ester resin, an imide-based resin, a urethane-based resin, a urea resin, a melamine resin, etc., or an organic insulating material such as polystyrene, polyacrylonitrile, polycarbonate, etc., but not being limited thereto. In an alternative exemplary embodiment, the bank layer  206  may include an inorganic insulating material including an inorganic oxide and an inorganic nitride such as SiOx, SiNx, SiNxOy, AlOx, TiOx, TaOx, ZnOx, etc., but is not limited thereto. According to another alternative exemplary embodiment, the bank layer  206  may include an opaque material such as a black matrix material. In an exemplary embodiment, the insulating black matrix material may include an organic resin, glass paste, a resin including black pigment or paste, a metallic particle, for example, Ni, Al, Mo, and an alloy thereof, a metallic oxide particle (for example, a chrome oxide), or a metallic nitride particle (for example, a chrome nitride). The bank layer  206  is not limited to the above materials, and may include various materials depending on the structure of the LED  230 , connection of the LED  230  and the electrodes, etc. 
         [0145]    A passivation layer  213  may be disposed in a space between the bank layers  206 . In an exemplary embodiment, the passivation layer  207  may be disposed between the LED  230  and the bank layer  206  and effectively prevent a second electrode  212  from contacting the first electrode  211 . 
         [0146]    The passivation layer  213  may be transparent or semitransparent with respect to a visible wavelength and thus may not substantially deteriorate light extraction efficiency of a completed system. A lateral wall passivation layer may include various materials, for example, epoxy, PMMA, benzocyclobutene (“BCB”), polyimide, and polyester, but is not limited thereto. According to an exemplary embodiment, the passivation layer  207  is formed around the LED  230  by an ink jet method. 
         [0147]    The LED  230  emits red, green or blue light, and may produce white light by using a fluorescent material or combining colors. The LED  230  may include a first semiconductor layer  231 , a second semiconductor layer  232  and an intermediate layer  233  between the first semiconductor layer  231  and the second semiconductor layer  232 . 
         [0148]    The first semiconductor layer  231  may be implemented as, for example, a p-type semiconductor layer. The p-type semiconductor layer may include a semiconductor material having a composition equation of In x Al y Ga 1-x-y N (0≦x≦1, 0≦y=1, 0≦x+y≦1), and may include, for example, GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, etc. The first semiconductor layer  231  may be doped with p-type dopants such as Mg, Zn, Ca, Sr, and Ba. 
         [0149]    The second semiconductor layer  232  may include, for example, an n-type semiconductor layer. An n-type semiconductor layer may include a semiconductor material having a composition equation of In x Al y Ga 1-x-y N (0≦x≦1, 0≦y≦1, 0≦x+y≦1), and may include, for example, GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, etc. The second semiconductor layer  232  may be doped with n-type dopants such as Si, Ge, and Sn. 
         [0150]    However, exemplary embodiments are not limited thereto, and alternatively, the first semiconductor layer  231  may include the n-type semiconductor layer and the second semiconductor layer  232  may include the p-type semiconductor layer. 
         [0151]    The intermediate layer  233  is a region where electrons and holes recombine. When the electron and the hole recombine, they may make transition to a lower energy level and emit light having a corresponding wavelength. The intermediate layer  233  may include a semiconductor material having a composition equation of In x Al y Ga 1-x-y N (0≦x≦1, 0≦y≦1, 0≦x+y≦1), and may include a single quantum well structure or a multi-quantum well (“MQW”) structure. In such an embodiment, the intermediate layer  233  may include a quantum wire structure or a quantum dot structure. 
         [0152]    A first electrode pad  235  may be provided or formed on the first semiconductor layer  231 , and a second electrode pad  237  may be provided or formed on the second semiconductor layer  232 . The first electrode pad  235  may be bonded to the first electrode  211 . In an exemplary embodiment where the LED  230  has a vertical structure, the second electrode pad  237  may be located on the opposite side of the first electrode pad  235 , and the second electrode  212  contacting the second electrode pad  237  may be disposed on the emission layer  210 . 
         [0153]    The first electrode  211  may include a reflective layer including Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, and a compound thereof, and a transparent or semitransparent electrode layer on the reflective layer. The transparent or semitransparent electrode layer may include at least one selected from indium tin oxide (“ITO”), indium zinc oxide (“IZO”), zinc oxide (ZnO), indium oxide (In 2 O 3 ), indium gallium oxide (“IGO”), and aluminum zinc oxide (“AZO”). 
         [0154]    The second electrode  212  may be provided or formed on the entire surface of the emission layer  210 . The second electrode  212  may be a transparent or semitransparent electrode, and include a metallic thin film having a small work function and including Li, Ca, LiF/Ca, LiF/Al, Al, Ag, Mg, and a compound thereof. In an exemplary embodiment, an auxiliary electrode layer or a bus electrode including a material for forming a transparent electrode such as ITO, IZO, ZnO, or In 2 O 3  may be formed on the metallic thin film. Therefore, the second electrode  212  may transmit light emitted from the LED  230 . 
         [0155]    However, exemplary embodiments of the display device are not limited to the top-emission type display device, and may be a bottom-emission type display device in which light emitted from the LED  230  is emitted toward the substrate  201 . In an exemplary embodiment, the first electrode  211  may include a transparent or semitransparent electrode, and the second electrode  212  may include a reflective electrode. In an alternative exemplary embodiment, the display device  10  may be a dual-emission type display device that emits light in both directions including the front side and the bottom side. 
         [0156]    Although  FIG. 14  illustrates an exemplary embodiment including a vertical LED  230  in which the first electrode pad  235  and the second electrode pad  237  are disposed opposite to each other, exemplary embodiments are not limited thereto. In an alternative exemplary embodiment, the LED  230  may be a horizontal type LED or a flip type LED (not shown) in which the first electrode pad  235  and the second electrode pad  237  are disposed to face toward a same direction. 
         [0157]    The horizontal type LED includes a first semiconductor layer (not shown), a second semiconductor layer (not shown), and an intermediate layer (not shown) between the first and second semiconductor layers. A first electrode pad (not shown) is provided or formed on the first semiconductor layer, and a second electrode pad (not shown) is provided or formed on the second semiconductor layer. In such an embodiment, both the first electrode pad and the second electrode pad may be disposed to face toward a same direction. 
         [0158]    In such an embodiment, a portion of the first semiconductor layer and the intermediate layer is removed to expose a portion of the second semiconductor layer. The second electrode pad may be provided or formed on the exposed portion of the second semiconductor layer. In such an embodiment, the area of the second semiconductor layer is greater than the area of the first semiconductor layer and the intermediate layer, and the second electrode pad may be disposed on a portion of the second semiconductor layer that protrudes to the outside of the first semiconductor layer and the intermediate layer. 
         [0159]    In such an embodiment, the second electrode contacting the second electrode pad may be provided or formed on a planarization layer (not shown). The second electrode may be provided or formed on a position spaced apart from the first electrode, and formed in a layer in which the first electrode is formed. In an alternative exemplary embodiment, an insulating layer may be disposed between the second electrode and the first electrode, and an opening that exposes the first electrode or the second electrode may be formed in the insulating layer. 
         [0160]    The plurality of LEDs  230  may be provided or formed on the first substrate  1 . The first substrate  1  may include a conductive substrate or an insulating substrate, and may include, for example, at least one selected from Al 2 O 3 , SiC, Si, GaAs, GaN, ZnO, Si, GaP, InP, Ge, and Ga 2 O 3 . 
         [0161]    Each of the plurality of LEDs  230  may include the first semiconductor layer  231 , the second semiconductor layer  232 , and the intermediate layer  233  between the first semiconductor layer  231  and the second semiconductor layer  232 . The first semiconductor layer  231 , the intermediate layer  233  and the second semiconductor layer  232  may be formed by using a method such as metal organic chemical vapor deposition (“MOCVD”), chemical vapor deposition (“CVD”), plasma-enhanced chemical vapor deposition (“PECVD”), molecular beam epitaxy (“MBE”), or hydride vapor phase epitaxy (“HVPE”). The first electrode pad  235  may be formed on the first semiconductor layer  231 , and the second electrode pad  237  may be formed on the second semiconductor layer  232 . 
         [0162]    After the plurality of LEDs  230  are transferred onto the second substrate  200 , the second electrode  212  contacting the second electrode pad  237  may be formed on the emission layer  210 . The second electrode  212  may be formed, for example, on the entire surface of the emission layer  210 . 
         [0163]    In an exemplary embodiment, as described above, the manufacturing method of the display device  10  may include a method or process of transferring the vertical LED  230  in which the first electrode pad  235  and the second electrode pad  237 , but not being limited thereto. An alternative exemplary embodiment of the manufacturing method of the display device  10  may include a method or process of transferring horizontal or flip type LEDs  230  onto the second substrate  200 . 
         [0164]    Each of the horizontal or flip type LEDs  230  may include a first semiconductor layer (not shown), a second semiconductor layer (not shown), and an intermediate layer (not shown) between the first semiconductor layer and the second semiconductor layer. A first electrode pad (not shown) is formed on the first semiconductor layer, and a second electrode pad (not shown) is formed on the second semiconductor layer. Both the first electrode pad and the second electrode pad may be disposed to face toward the same direction. 
         [0165]    In such an embodiment, while the plurality of LEDs  230  are formed, mesa etching may be performed on a region ranging from the first semiconductor layer to a portion of the second semiconductor layer by using reactive ion etching (“RIE”), etc., such that a portion of the second semiconductor layer may be exposed, and then the second electrode pad may be formed on the second semiconductor layer. 
         [0166]    In such an embodiment, the first electrode pad and the second electrode pad are simultaneously provided or formed together on the second substrate  200 . The second electrode is formed on a position spaced apart from the first electrode. The second electrode may be formed in a layer in which the first electrode is formed, or an insulating layer may be disposed between the second electrode and the first electrode, and an opening that exposes the first electrode or the second electrode may be formed in the insulating layer. 
         [0167]    The horizontal or flip type LEDs  230  may be transferred onto the second substrate  200  by using the same method as the method described above. In an exemplary embodiment, the first electrode pad may be bonded to the first electrode, and the second electrode pad may be bonded to the second electrode. Hereinafter, for convenience of description, an exemplary embodiment directed to the vertical LED  230  will be mainly described. 
         [0168]    A separate encapsulation portion  214  may be provided or installed on the second electrode  212  to protect the LED  230  from oxygen and moisture. In an exemplary embodiment, the encapsulation portion  214  may include an encapsulation substrate (not shown) including a material that is the same as or similar to that of the substrate  201 , or a thin film (not shown) including at least one of an organic layer and an inorganic layer. For convenience of description, an exemplary embodiment where the encapsulation portion  214  includes the thin film will hereinafter be mainly described. 
         [0169]    Therefore, the LED transfer  100  may increase productivity by simultaneously transferring a plurality of LEDs. In such an embodiment, the LED transfer  100  may reduce a consumed time by sequentially picking up and transferring a plurality of LEDs  230 . 
         [0170]    The LED transfer  100  may pick up an LED of various shapes and dispose the LED on various positions. 
         [0171]      FIG. 15  is a side cross-sectional view illustrating an LED transfer  100 A according to an alternative exemplary embodiment.  FIG. 16  is a cross-sectional view illustrating a first linear driving portion of the LED transfer  100 A illustrated in  FIG. 15 .  FIG. 17  is a schematic plan view illustrating the arrangement of LEDs transferred from a first substrate to a second substrate via the LED transfer  100 A illustrated in  FIG. 15 . 
         [0172]    Referring to  FIGS. 15 to 17 , an exemplary embodiment of the LED transfer  100 A may include a chamber  110 A, a stage  120 A, a moving portion  130 A, a first linear driving portion  140 A, a second linear driving portion  150 A, a head portion  160 A and a vision portion  170 A. In such an embodiment, the chamber  110 A, the stage  120 A, the moving portion  130 A, and the vision portion  170 A are the same as or similar to those described above, and any repetitive detailed description thereof will be omitted. 
         [0173]    In such an embodiment, the first linear driving portion  140 A may be formed in the various shapes as described above. Hereinafter, an exemplary embodiment of the first linear driving portion  140 A will be described in detail with reference to  FIG. 16 . 
         [0174]    An exemplary embodiment of the first linear driving portion  140 A may include a first driving motor  141 A, a first ball screw  142 A, and a first guide portion  143 A. In such an embodiment, the first driving motor  141 A may be fixed to the stage  120 A. In such an embodiment, the first ball screw  142 A may be installed to pass through the moving portion  130 A and connected with the first driving motor  141 A. 
         [0175]    The first ball screw  142 A may include a first connection portion  142 A- 2  coupled to the moving portion  130 A, and a first screw portion  142 A- 1  inserted into the first connection portion  142 A- 2  and which rotates. In an exemplary embodiment, the first screw portion  142 A- 1  may be connected with the first driving motor  141 A and rotate when the first driving motor  141 A rotates. In such an embodiment, the first connection portion  142 A- 2  may linearly move along the first screw portion  142 A- 1  when the first screw portion  142 A- 1  rotates. 
         [0176]    The first guide portion  143 A may be disposed between the moving portion  130 A and the stage  120 A and reduce frictional force between the moving portion  130 A and the stage  120 A. In an exemplary embodiment, the first guide portion  143 A may have various shapes, such as a linear motion guide, and lubricant. In one exemplary embodiment, for example, the first guide portion  143 A may be defined by any unit, structure, and a material disposed between objects for performing relative motion and reducing frictional force. For convenience of description, an exemplary embodiment where the first guide portion  143 A includes a linear motion guide will hereinafter be mainly described. 
         [0177]    The second linear driving portion  150 A may be in the various shapes as described above. Hereinafter, an exemplary embodiment of the second linear driving portion  150 A will be described in detail below with reference to  FIG. 15 . 
         [0178]    Similar to the first linear driving portion  140 A, the second linear driving portion  150 A may include a second driving motor  151 A and a second ball screw  153 A. In an exemplary embodiment, the second ball screw  153 A may include a second connection portion  153 A- 2  and a second screw portion  153 A- 1 . The second connection portion  153 A- 2  may be inserted into the head portion  160 A and fixed thereto. In such an embodiment, the second screw portion  153 A- 1  may be installed to pass through the head portion  160 A and have an end connected with the second driving motor  151 A. 
         [0179]    The head portion  160 A may include a head body portion  161 A, a pick-up portion  162 A, and a rotation driving portion  163 A. In an exemplary embodiment, the second screw portion  153 A- 1  may be installed inside the rotation driving portion  163 A to pass through the rotation driving portion  163 A. 
         [0180]    The head body portion  161 A may be in various shapes. In one exemplary embodiment, for example, the head body portion  161 A may be in a plate shape. According to an alternative exemplary embodiment, the head body portion  161 A may be in a bar shape. However, the head body portion  161 A is not limited thereto and may be modified to be in various shapes. 
         [0181]    The pick-up portion  162 A may be disposed on the head body portion  161 A. In an exemplary embodiment, the pick-up portion  162 A may be provided in plural, and disposed on the surface of the head body portion  161 A so that the pick-up portions  162 A may be spaced apart from each other with a predetermined interval. 
         [0182]    The rotation driving portion  163 A may rotate the head body portion  161 A. In an exemplary embodiment, the rotation driving portion  163 A may rotate the head body portion  161 A around a load applied direction of the head body portion  161 A as a rotational axis. The rotation driving portion  163 A may include a motor. 
         [0183]    The LED transfer  100 A may transfer the LED  230 A from the first substrate  1  to the second substrate  200 . 
         [0184]    In an exemplary embodiment, after the moving portion  130 A is located on the first substrate  1 , a position between the head portion  160 A and the first substrate  1  is detected via the vision portion  170 A, and the position of the head portion  160 A may be adjusted to a predetermined position by using the first linear driving portion  140 A and the second linear driving portion  150 A. In such an embodiment where the head portion  160 A is located on the predetermined position when the second linear driving portion  150 A operates, the head body portion  161 A may descend and the LED  230  may be attached on the pick-up portion  162 A. In such an embodiment, when the second linear driving portion  150 A operates reversely, the head body portion  161 A may ascend, and the LED  230  together with the pick-up portion  162 A may be separated from the first substrate  1 . In an exemplary embodiment, since a method of separating the LED  230  from the first substrate  1  is the same as or similar to the above-described method, and any repetitive detailed description thereof will be omitted. 
         [0185]    As described above, the LED  230  is picked up, and the first linear driving portion  140 A may operate to dispose the head portion  160 A to the second substrate  200 . In such an embodiment, the vision portion  170 A may capture a position relation between the head portion  160 A and the second substrate  200 , and the first linear driving portion  140 A and the second linear driving portion  150 A may adjust the position of the head portion  160 A so that the head portion  160 A may correspond to the second substrate  200 . 
         [0186]    After the position adjustment of the head portion  160 A is performed, the rotation driving portion  163 A may operate to tilt the head body portion  161 A. In an exemplary embodiment, when the rotation driving portion  163 A operates, the head body portion  161 A may rotate around a z-axis of  FIG. 15  as a rotational axis. In an exemplary embodiment where the LED  230  has a quadrangular shape when viewed from a plan view, the LED  230  may be arranged in a rhombus shape depending on the structure of the second substrate  200 . In an exemplary embodiment, when the LED  230  is directly transferred onto the second substrate  200  with the head body portion  161 A picked-up from the first substrate  1  while the head body portion  161 A is not rotated, the shape of a portion of the second substrate  200  on which the LED  230  is seated and the shape of the LED  230  may not correspond to each other. In such an embodiment, the rotation driving portion  163 A tilts the head portion  160 A around a z-axis of  FIG. 15  as a rotational axis, so that the quadrangular LED  230  may be arranged in a rhombus shape. 
         [0187]    The LED  230  on the pick-up portion  162 A may be transferred onto the second substrate  200  by tilting the head body portion  161 A and operating the second linear driving portion  150 A to lower the head body portion  161 A. 
         [0188]    In such an embodiment, the above operation may be repeatedly performed until all of the LEDs  230  are transferred onto the second substrate  200 . 
         [0189]    Therefore, the LED transfer  100 A may increase productivity by simultaneously transferring the plurality of LEDs  230 . In such an embodiment, the LED transfer  100 A may reduce a consumed time by sequentially picking up and transferring the plurality of LEDs  230 . 
         [0190]    The LED transfer  100 A may pick up an LED of various shapes and dispose the same on various positions. In such an embodiment, the LED transfer  100 A tilts the LED  230  having a predetermined shape by a predetermined angle and transfers the LED  230 , so that the LED  230  of various arrangements may effectively be transferred. 
         [0191]      FIG. 18  is a side cross-sectional view illustrating an LED transfer  100 B according to another exemplary embodiment.  FIG. 19  is a cross-sectional view illustrating a first linear driving portion of the LED transfer  100 B illustrated in  FIG. 18 . 
         [0192]    Referring to  FIGS. 18 and 19 , an exemplary embodiment of the LED transfer  100 B may include a chamber  110 B, a stage  120 B, a moving portion  130 B, a first linear driving portion  140 B, a second linear driving portion  150 B, a head portion  160 B, and a vision portion  170 B. In an exemplary embodiment, the chamber  110 B, the stage  120 B, the moving portion  130 B and the vision portion  170 B are the same as or similar to those described above, and any repetitive detailed description thereof will be omitted. 
         [0193]    The first linear driving portion  140 B may be in various shapes as described above. Hereinafter, an exemplary embodiment of the first linear driving portion  140 B will be described in detail with reference to  FIG. 18 . 
         [0194]    In an exemplary embodiment, the first linear driving portion  140 B may include a first driving motor  141 B, a first pulley  142 B- 1 , a second pulley (not shown), a first wire  144 B, and a first guide portion  143 B. In such an embodiment, the first wire  144 B may pass through the moving portion  130 B and may be wound on one of the first pulley  142 B- 1  and the second pulley, or released from the other of the first pulley  142 B- 1  and the second pulley. In such an embodiment, the first driving motor  141 A may be connected to at least one of the first pulley  142 B- 1  and the second pulley and rotate at least one of the first pulley  142 B- 1  and the second pulley. 
         [0195]    The first wire  144 B may be fixed inside the moving portion  130 B. In such an embodiment, the first pulley  142 B- 1  and the second pulley may be installed to face each other in a length direction (an x-axis direction of  FIG. 18 ) of the stage  120 B. 
         [0196]    The first guide portion  143 B may be installed between the moving portion  130 B and the stage  120 B. In an exemplary embodiment, the first guide portion  143 B may include a first rail portion  143 B- 1  installed to one of the moving portion  130 B and the stage  120 B, a first sliding portion  143 B- 2  seated and moving on the first rail portion  143 B- 1 , and a first bearing portion  143 B- 3  disposed between the first rail portion  143 B- 1  and the first sliding portion  143 B- 2 . For convenience of description, an exemplary embodiment where the first rail portion  143 B- 1  is disposed on the stage  120 B will hereinafter be mainly described. 
         [0197]    The second linear driving portion  150 B may be in various shapes as described above. However, for convenience of description, an exemplary embodiment where the second linear driving portion  150 B includes a cylinder will hereinafter be mainly described. 
         [0198]    In such an embodiment, the second linear driving portion  150 B may include a position variation portion  151 B and a fixing bracket  152 B. The head portion  160 B may include a head body portion  161 B, a pick-up portion  162 B, and rotation driving portions  163 B and  164 B. In such an embodiment, the head body portion  161 B and the pick-up portion  162 B are the same as or similar to those described above, and any repetitive detailed description thereof will be omitted. 
         [0199]    The rotation driving portion may include the first rotation driving portion  164 B disposed between the fixing bracket  152 B and the position variation portion  151 B and connecting the fixing bracket  152 B with the position variation portion  151 B. In such an embodiment, the rotation driving portion may include the second rotation driving portion  163 B installed to the fixing bracket  152 B and connected to the head body portion  161 B. 
         [0200]    In an exemplary embodiment, the first rotation driving portion  164 B may include the above-described general motor. The second rotation driving portion  163 B may include a rotation motor  163 B- 1  and a rotational shaft  163 B- 2 . The rotation motor  163 B- 1  may be installed to the fixing bracket  152 B, and connected to the rotational shaft  163 B- 2  installed to pass through the head body portion  161 B. 
         [0201]    An operation of the LED transfer  100 B may be the same as or similar to that described above. The LED transfer  100 B may pick up the LED  230  of a first substrate (not shown) by using the pick-up portion  162 B and transfer the LED  230  onto the second substrate  200 . 
         [0202]    In an exemplary embodiment, the vision portion  170 B may capture a position relation between the first substrate and the head portion  160 B, and a position relation between the second substrate  200  and the head portion  160 B, and provide a base for adjusting the position of the head portion  160 B. 
         [0203]    In such an embodiment, the first linear driving portion  140 B may dispose the head portion  160 B on the first substrate and the second substrate  200  by moving the moving portion  130 B. The second linear driving portion  150 B may allow the pick-up portion  162 B to pick up the LED  230  of the first substrate by raising/lowering the head portion  160 B, and transfer the LED  230  on the pick-up portion  162 B onto the second substrate  200 . 
         [0204]    The first rotation driving portion  164 B may rotate the fixing bracket  152 B and the head body portion  161 B around a load applied direction (or a z-axis of  FIG. 18 ) of the head body portion  161 B as a rotational axis. In an exemplary embodiment, as described above, the LED  230  having a quadrangular shape may be transferred onto the second substrate  200  in a rhombus shape. 
         [0205]    In an exemplary embodiment, the second rotation driving portion  163 B may rotate the head body portion  161 B around a length direction (or a y-axis of  FIG. 18 ) of the head body portion  161 B as a rotational axis. In such an embodiment, it is possible to pick up a plurality of LEDs  230  at a time by using a plurality of pick-up portions  162 B forming a plurality of lines on the surface of the head body portion  161 B, and sequentially transfer the plurality of LEDs  230  onto the second substrate  200 . 
         [0206]    In an exemplary embodiment described herein, the LED transfer  100 B may increase productivity by simultaneously transferring the plurality of LEDs  230 . In such an embodiment, the LED transfer  100 B may reduce a consumed time by sequentially picking up and transferring the plurality of LEDs  230 . 
         [0207]    In an exemplary embodiment, the LED transfer  100 B may pick up an LED of various shapes and dispose the same on various positions. In such an embodiment, the LED transfer  100 B tilts the LED  230  having a predetermined shape by a predetermined angle and transfers the same, so that the LED  230  of various arrangements may be transferred. 
         [0208]    Though the inventive concept has been described with reference to exemplary embodiments illustrated in the drawings, these are provided for an exemplary purpose only, and those of ordinary skill in the art will understand that various modifications and other equivalent embodiments may be made therein. Therefore, the spirit and scope of the inventive concept should be defined by the following claims.