KR20230006361A - A display layer having monolithic structure and a display device including the display layer - Google Patents

Abstract

The present disclosure relates to a display layer in which a plurality of light emitting elements and a plurality of switching elements have a monolithic structure and a display device including the same. The display device includes a display layer and a driving layer. In the display layer, a plurality of light emitting elements and a plurality of switching elements corresponding thereto are grouped and arranged in pixel units. The driving layer includes a plurality of driving elements that apply at least one driving signal to the display layer.

Description

A display layer having a monolithic structure and a display device including the same

The present disclosure relates to a display layer having a monolithic structure and a display device including the same.

A micro LED (Light Emitting Diode) display module is composed of a display layer and a CMOS (Complementary Metal Oxide Silicon) backplane. After the display layer and CMOS backplane are fabricated separately, they are fabricated into a module through a bonding process. . During the bonding process, a pair of bonding pads for each sub-pixel or a pair of bonding pads for each light emitting device are positioned between the display layer and the CMOS backplane to bond the display layer and the CMOS backplane. As the pixel density (pixels per inch, PPI) of the module increases (or as the pixel pitch decreases), the spacing between bonding pads (hereinafter referred to as bonding pitch) decreases. As the spacing between the bonding pads decreases, the difficulty of processing and aligning the bonding surface increases, resulting in a decrease in yield.

According to an exemplary embodiment, a display layer and a display device including the same may include a display layer having a monolithic structure to secure a gap between a plurality of bonding pads.

In the display device according to an exemplary embodiment, a plurality of light emitting elements and a plurality of switching elements corresponding to the plurality of light emitting elements are grouped and arranged in pixel units, and the plurality of light emitting elements and the plurality of switching elements are monolithic. A display layer as one structure and a driving layer including a plurality of driving elements for applying at least one driving signal to the display layer may be included, and the display layer may include a plurality of pixels.

In addition, the plurality of driving elements and the plurality of pixels correspond to each other on a one-to-one basis, and the plurality of driving elements may apply a driving signal corresponding to each of the plurality of pixels.

In addition, a plurality of corresponding driving elements and a plurality of pixels may be electrically connected by a plurality of bonding pad pairs disposed between the driving layer and the display layer.

Further, the distance between the plurality of bonding pad pairs may be equal to or greater than the distance between adjacent pixels of the display device.

Also, the distance between the plurality of bonding pad pairs may be substantially equal to or greater than that between adjacent light emitting elements of the display device.

The plurality of pixels may include a first pixel and a second pixel, and a first driving element among the plurality of driving elements may apply a first driving signal to the first pixel and the second pixel.

In addition, the plurality of pixels include a first pixel, the first driving element among the plurality of driving elements applies a first driving signal to the first pixel, and each of the plurality of light emitting elements disposed in the first pixel corresponds to the first pixel. Different parts of the first driving signal may be applied by a plurality of switching elements corresponding to each of the plurality of light emitting elements arranged on the .

In addition, the different parts of the first driving signal are time-sequentially separated from the first driving signal, and the time-sequentially separated may be achieved by sequential switching operations of a plurality of switching elements.

In addition, the display layer includes a light emitting layer including a plurality of light emitting elements and a switching layer disposed between the light emitting layer and the driving layer and including a plurality of switching elements, and there may be no bonding layer between the light emitting layer and the switching layer.

The driving layer may further include a plurality of switch control blocks that control the plurality of switching elements so that different parts of the driving signals are allocated to the plurality of light emitting elements.

In addition, the driving layer may include a data control block including a plurality of column lines and a scan control block including a plurality of row lines, One driving element corresponding to one pixel among the plurality of pixels is connected to one column line among the plurality of column lines and one row line among the plurality of row lines, and the one row line corresponds to one switch control block among the plurality of switch control blocks. Some of the plurality of light emitting elements are included in a plurality of pixels connected to one row line, and a plurality of switching elements corresponding to some of the plurality of light emitting elements may be controlled by one switch control block.

Further, one switch control block includes a plurality of connection lines, and one switch control block is connected to the display layer through bonding pads equal in number to the number of light emitting elements included in one pixel, and the plurality of connection lines are It extends along a plurality of pixels connected to one row line and may be connected to a plurality of switching elements corresponding to portions of a plurality of light emitting elements included in a plurality of pixels connected to one row line.

In addition, a plurality of pixels connected to one row line include a first pixel and a second pixel, and one of the plurality of connection lines includes a first switching element corresponding to the first light emitting element included in the first pixel and a second connection line. It may be connected to a second switching element corresponding to a second light emitting element included in 2 pixels.

For example, at least one of the plurality of light emitting devices may have a size of 0.1 um to 200 um.

The display layer according to an exemplary embodiment has a monolithic structure in which a plurality of light emitting elements and a plurality of switching elements corresponding to the plurality of light emitting elements are grouped and arranged in pixel units, and the plurality of light emitting elements and the plurality of switching elements are monolithic. , may include a plurality of pixels.

The display layer may include a light emitting layer including a plurality of light emitting elements and a switching layer including a plurality of switching elements, and there may be no bonding layer between the light emitting layer and the switching layer.

In addition, a plurality of bonding pads corresponding to the plurality of pixels and disposed on one side of the display layer may be further included.

Also, the distance between the plurality of bonding pads may be equal to or greater than the distance between adjacent pixels of the display layer.

Also, the spacing between the plurality of bonding pads may be substantially equal to or greater than the spacing between adjacent light emitting elements of the display layer.

For example, at least one of the plurality of light emitting devices may have a size of 0.1 um to 200 um.

A display device according to an exemplary embodiment may include a display layer having a monolithic structure to increase a bonding interval between bonding pads.

In the display device according to the exemplary embodiment, yield may be improved when manufacturing the display device as the bonding interval is secured.

A display device according to an exemplary embodiment may be used when manufacturing a micro LED display having a high PPI.

A pair of bonding pads disposed on the display device according to an exemplary embodiment may correspond to at least one pixel, and the pair of bonding pads may be connected to one driving element. That is, since a plurality of light emitting elements or a plurality of sub-pixels can be connected to each driving element, the number of driving elements disposed on the substrate can be reduced, and thus the driving voltage, manufacturing cost, and manufacturing time of the display device can be reduced.

1A is a cross-sectional view of a display layer and a display device including the display layer according to an exemplary embodiment.
FIG. 1B is a diagram illustrating arrangements of a display layer, a driving layer corresponding thereto, and a pair of bonding pads disposed thereon according to an exemplary embodiment.
2A is a cross-sectional view of a display layer and a display device including the display layer according to the prior art.
FIG. 2B is a diagram illustrating arrangements of a display layer, a driving layer corresponding thereto, and a pair of bonding pads disposed thereon according to the related art.
Fig. 3 shows a conceptual diagram of a first pixel and a first region of a display device according to an exemplary embodiment.
Fig. 4 shows a conceptual diagram of a display device according to an exemplary embodiment.
Fig. 5 shows a conceptual diagram of a display device according to an exemplary embodiment.
6 illustrates a display device including a color conversion layer according to an exemplary embodiment.
7 illustrates an example in which a display device according to an exemplary embodiment is applied to a mobile device.
8 illustrates an example in which a display device according to an exemplary embodiment is applied to a vehicle.
9 illustrates an example in which a display device according to an exemplary embodiment is applied to augmented reality glasses or virtual reality glasses.
10 illustrates an example in which a display device according to an exemplary embodiment is applied to a wearable display.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. The described embodiments are merely illustrative, and various modifications are possible from these embodiments. In the following drawings, the same reference numerals denote the same components, and the size of each component in the drawings may be exaggerated for clarity and convenience of description.

Hereinafter, what is described as "above" or "above" may include not only what is directly on top of contact but also what is on top of non-contact. Similarly, references to "below" or "beneath" may include directly under contact as well as under non-contact.

Expressions in the singular number include plural expressions unless the context clearly dictates otherwise. In addition, when a certain component is said to "include", this means that it may further include other components without excluding other components unless otherwise stated.

The use of the term “above” and similar denoting terms may correspond to both singular and plural.

The meaning of “connection” may include not only a physical connection, but also an optical connection, an electrical connection, and the like.

In addition, the use of all exemplary terms (for example, etc.) is simply for explaining technical ideas in detail, and the scope of rights is not limited due to these terms unless limited by claims.

Terms such as 1st and 1-1 may be used to describe various elements, but elements should not be limited by the terms. Terms are used only to distinguish one component from another.

1A is a cross-sectional view of a display layer 100 according to an exemplary embodiment and a display device 10 including the display layer 100 according to an exemplary embodiment, and FIG. 1B is a display layer 100 according to an exemplary embodiment and a driving layer corresponding thereto ( 200) and the arrangement of bonding pad pairs 130 and 230 disposed thereon.

2A is a cross-sectional view of a display layer 1100 according to the prior art and a display device including the same, and FIG. 2B is a display layer 1100 according to the prior art, a driving layer 1200 corresponding thereto, and bondings disposed thereon. It is a diagram showing the arrangement of the pad pairs 1130 and 1230.

1A and 1B , the display layer 100 according to an exemplary embodiment includes a plurality of light emitting elements 111 and a plurality of switching elements 121 corresponding to the plurality of light emitting elements 111 in a pixel unit. Grouped and arranged, the plurality of light emitting elements 111 and the plurality of switching elements 121 may have a monolithic structure. The monolithic structure can be seen as one side of the light emitting layer 110 including the light emitting element 111, and the switching layer 120 including the switching element 121 is single grown together with the light emitting layer 110. Alternatively, the monolithic structure may mean that there is no bonding layer between the light emitting layer 110 and the switching layer 120 . Here, the display layer 100 may include a plurality of pixels.

The display device 10 according to an exemplary embodiment includes a driving layer 200 including the aforementioned display layer 100 and a plurality of driving elements 210 for applying at least one driving signal to the display layer 100 . can include At least one driving signal may correspond to a plurality of pixels, or one driving signal may correspond to two or more pixels. The driving layer 200 may be bonded and/or connected to the display layer 100, and such bonding may be achieved by bonding pads 130 disposed on the display layer 100 and disposed on the driving layer 200 corresponding thereto. This may be achieved by bonding between the plurality of bonding pads 230 . However, bonding of the display device 10 according to the exemplary embodiment is not limited thereto and may be bonded in various ways.

The display layer 100 according to an exemplary embodiment may include a plurality of pixels. A plurality of pixels may be exclusive without overlapping each other. The first pixel P1 included in the plurality of pixels may include some of the plurality of light emitting elements 111 . In other words, some of the plurality of light emitting elements 111 may be disposed in the first pixel P1 . The first pixel P1 may include at least one light emitting element 111, and for example, to configure one pixel, the first pixel P1 may include three or more light emitting elements 111. can At least one light emitting element 111 included in the first pixel P1 may constitute one sub-pixel. Light of the same color may be emitted from one sub-pixel. That is, if one sub-pixel includes a plurality of light emitting elements 111, the plurality of light emitting elements 111 included in the same sub-pixel can emit light of the same color, or can emit light of the same color on the display layer 100. If a conversion layer (not shown) is disposed, color light emitted from the plurality of light emitting elements 111 included in the same sub-pixel may pass through the same color conversion layer.

The first to fourth light emitting devices 111 may be included in the first pixel P1 of the display layer 100 according to an exemplary embodiment. For example, the first light emitting device may emit red light, the second light emitting device may emit green light, the third light emitting device may emit blue light, and the fourth light emitting device may emit white light. Alternatively, for example, the first light emitting device may emit red light, the second light emitting device may emit green light, the third light emitting device may emit green light having a different wavelength from the green light of the second light emitting device, and the fourth light emitting device may emit blue light. However, it is not limited to this example, and each light emitting element 111 may emit light of a different color. According to the above exemplary embodiments, the first pixel P1 may constitute one pixel. Although the above embodiment shows that the plurality of light emitting elements 111 and the plurality of switching elements 121 are grouped and arranged in pixel units, the plurality of light emitting elements 111 and the plurality of switching elements 121 are not limited thereto. ) may be grouped and arranged. For example, a plurality of light emitting elements 111 and a plurality of switching elements 121 (hereinafter referred to as a first group) grouped may not constitute one pixel, and a first group is associated with a second group adjacent thereto. Together, they may constitute one pixel.

The display layer 100 according to an exemplary embodiment may include a light emitting layer 110 including a plurality of light emitting elements 111 . The display layer 100 may include an ion implantation region 113 . A semiconductor layer may be doped along the ion implantation region 113 . Among the plurality of light emitting elements 111, one light emitting element 111 may include a first semiconductor layer 111a, an active layer 111b, and a second semiconductor layer 111c, and may be disposed in the above order. The first semiconductor layer 111a and the second semiconductor layer 111c may be made of a II-VI group or III-V group compound semiconductor material. The first semiconductor layer 111a and the second semiconductor layer 111c serve to provide electrons and holes to the active layer 111b. To this end, the first semiconductor layer 111a may be doped with an n-type or p-type, and the second semiconductor layer 111c may be doped with a conductivity type that is electrically opposite to that of the first semiconductor layer 111a. For example, the first semiconductor layer 111a may be doped with p-type, the second semiconductor layer 111c may be doped with n-type, the first semiconductor layer 111a may be doped with n-type, and the second semiconductor layer 111a may be doped with n-type. The semiconductor layer 111c may be doped with p-type. When the second semiconductor layer 111c is doped with n-type, for example, silicon (Si) can be used as a dopant, and when the first semiconductor layer 111a is doped with p-type , For example, zinc (Zn) may be used as a dopant. At this time, the n-type doped second semiconductor layer 111c may provide electrons to the active layer 111b, and the p-type doped first semiconductor layer 111a may provide holes to the active layer 111b. can

The active layer 111b has a quantum well structure in which quantum wells are disposed between barriers. Light may be emitted as electrons and holes provided from the first semiconductor layer 111a and the second semiconductor layer 111c recombine within the quantum well structure of the active layer 111b. A wavelength of light generated in the active layer 111b may be determined according to a bandgap of a material constituting the quantum well in the active layer 111b. The active layer 111b may have a single quantum well structure or a multi-quantum well (MQW) structure in which multiple quantum wells and multiple barriers are alternately arranged. The thickness of the active layer 111b or the number of quantum wells in the active layer 111b may be appropriately selected in consideration of the driving voltage and luminous efficiency of the light emitting device 111 to be manufactured.

The active layer 111b may include a quantum barrier layer and a quantum well layer. For example, the quantum barrier layer may be composed of gallium nitride (GaN), and the quantum well layer may be composed of indium gallium nitride (In _x Ga _1-x N (0≤x≤1)). However, it is not limited to the above examples, and the quantum barrier layer or the quantum well layer may be composed of various materials. The active layer 111b may have a structure in which quantum barrier layers and quantum well layers are alternately stacked N times (where N is a natural number equal to or greater than 1), respectively.

Each of the plurality of light emitting devices 111 may have a size of about 0.1 to 1000 μm. Or it may have a size of about 0.1 to 200 μm or less. Preferably, it may have a size of about 100 μm or less. At this time, the size may mean, for example, the maximum length (hereinafter, the maximum length) of the lengths between two points on the light emitting element 111 . However, the size of the light emitting element 111 is not limited to the above range, and may be larger or smaller than the above range.

The display layer 100 according to an exemplary embodiment may include a switching layer 120 . The switching layer 120 may be a substrate integrally or monolithically formed or disposed with the light emitting layer 110 in a continuous process after the process/manufacturing of the light emitting layer 110 . The switching layer 120 may be integrally or monolithically disposed on the lower surface of the light emitting layer 110 . In this case, being integrally or monolithically disposed may mean that a separate bonding layer is not included between the switching layer 120 and the light emitting layer 110 . Accordingly, there is an advantage in that it is not necessary to consider an alignment error or the like according to the bonding process.

The switching layer 120 may include a plurality of switching elements 121 . The switching element 121 may include a thin film transistor (TFT), and the TFT may include various types of TFTs such as LTPS (Low-Temperature Polycrystalline Silicon), Oxide TFT, or GaN HEMT (Gallium Nitride High Electron Mobility Transistor). there is. One of the plurality of switching elements 121 of the switching layer 120 and one of the plurality of light emitting elements 111 of the light emitting layer 110 may be in a one-to-one correspondence, and the switching element 121 corresponds to the corresponding light emitting element 111 It can be connected to switch the light emitting element 111. However, it is not limited thereto, and one switching element 121 may correspond to one sub-pixel on a one-to-one basis, where one sub-pixel may include two or more light emitting elements 111 .

The first pixel P1 of the display layer 100 may include at least one light emitting element 111 , and a switching element 121 corresponding to the light emitting element 111 may be disposed on the switching layer 120 . For example, the first light emitting element included in the first pixel P1 may be driven through a first switching element corresponding to the first light emitting element, and the second light emitting element included in the first pixel P1 may be driven. It may be driven through a second switching element corresponding to the second light emitting element. One switching element 121 may be connected to correspond to one light emitting element 111 . When a first driving signal corresponding to the first pixel P1 is applied to the first pixel P1, a signal for driving the first light emitting element among the first driving signals is applied to the first light emitting element through the first switching element. and the first light emitting element can be driven. In addition, a signal for driving the second light emitting element among the first driving signals may be applied to the second light emitting element through the second switching element to drive the second light emitting element. The switch control block 250 may control the plurality of switching elements 121 so that a signal for driving each light emitting element 111 among driving signals is allocated to each light emitting element 111 . The switch control block 250 may be included in the driving layer 200 to be described later, each switching element 121 may be controlled by the switch control block 250, and light emission corresponding to each switching element 121 may be controlled. Different parts of the driving signal may be assigned to the device 111 . A description of the switch control block 250 will be given later.

The display layer 100 of the display device 10 according to an exemplary embodiment may further include an electrode 310 . The electrode 310 may be referred to as an n-type electrode if the second semiconductor layer 111c is n-type, and may be referred to as a p-type electrode if the second semiconductor layer 111c is p-type. Another electrode corresponding to the electrode 310 may be a connection node between the light emitting element 111 and the switching element 121 .

The display layer 100 according to an exemplary embodiment may further include a plurality of bonding pads 130 . The plurality of bonding pads 130 may be disposed on one surface of the display layer 100 , for example, may be disposed on a lower surface of the switching layer 120 . At least one bonding pad 130 may be disposed in each pixel, and it may be preferable that one bonding pad 130 be disposed in each pixel. However, the present invention is not limited thereto, and when one driving element 210 applies a driving signal to two or more pixels, one bonding pad 130 may be disposed for each of the two or more pixels. For example, a first bonding pad among a plurality of bonding pads 130 may be disposed in the first pixel P1 of the display layer 100 . The plurality of bonding pads 130 may serve to bond the display layer 100 to the driving layer 200 . When the display layer 100 and the driving layer 200 are bonded, the display device 10 can be formed. The driving layer 200 may also include a plurality of bonding pads 230 corresponding to the plurality of bonding pads 130 of the display layer 100 . The plurality of bonding pads 130 of the display layer 100 may be in one-to-one correspondence with the plurality of bonding pads 230 of the driving layer 200, and the two corresponding bonding pads 130 and 230 are formed as a bonding pad pair ( 130,230). When the bonding pad pairs 130 and 230 are bonded, this may be referred to as a bonding area BA0. The plurality of bonding pads 230 of the driving layer 200 may be made of substantially the same type of material as the plurality of bonding pads 130 of the display layer 100, and even different types of materials are used for bonding. It may substantially play the same role as the bonding pad 130 of the display layer 100 . When the bonding pad pairs 130 and 230 are bonded to each other (ie, when the bonding area BA0 is formed), the display layer 100 and the driving layer 200 may be bonded. Bonding of the display layer 100 and the driving layer 200 may be performed in various ways. For example, the display layer 100 and the driving layer 200 may be bonded through C2C (Copper to Copper) bonding.

When the display layer 100 and the driving layer 200 are bonded, a region of the driving layer 200 corresponding to the first pixel P1 of the display layer 100 may be referred to as a first region. A first bonding pad may be disposed on the first pixel P1 of the display layer 100 and a bonding pad corresponding to the first region of the driving layer 200 may be disposed. Only the first bonding pads may be disposed in the first pixel P1 , and similarly, only bonding pads corresponding to the first bonding pads (hereinafter referred to as first corresponding bonding pads) may be disposed in the first region. An area where the first bonding pad and the first corresponding bonding pad are bonded (hereinafter, referred to as a first bonding area) may be electrically connected. The plurality of light emitting devices 111 or the plurality of subpixels SP1 , SP2 , SP3 , and SP4 included in the first pixel P1 by the first bonding region may receive driving signals from the driving layer 200 . . Referring to FIGS. 2A and 2B , in the prior art, in order for one light emitting element 1111 or one subpixel (sp1, sp2, sp3, sp4) to receive a driving signal from the driving layer 1200, one light emitting element 1111 ) or a pair of bonding pads 1130 and 1230 for each sub-pixel sp1 , sp2 , sp3 , and sp4 . Accordingly, as the PPI increases (or as the pixel pitch decreases), the spacing between the bonding pads 1130 (hereinafter referred to as a bonding pitch) (bp1) decreases. As the bonding interval bp1 decreases, the difficulty of bonding surface processing and alignment accuracy increases, resulting in a decrease in yield. In the display device 10 including the display layer 100 and the driving layer 200 according to an exemplary embodiment, a plurality of light emitting elements 111 or a plurality of subpixels are connected to a driving signal by one bonding area BA0. By being able to be applied, a bonding interval BP1 wider than the bonding interval bp1 of the prior art is secured, and accordingly, yield reduction can be reduced or prevented. The spacing (bonding spacing) BP1 between the bonding pads 130 may be referred to as the spacing between the bonding areas BA0.

Referring to FIG. 1B , the first pixel P1 of the display layer 100 according to the exemplary embodiment may include first to fourth light emitting devices (not shown). The first light emitting device provides the first sub-pixel SP1, the second light emitting device provides the second sub-pixel SP2, the third light emitting device provides the third sub-pixel SP3, and the fourth light emitting device provides the fourth sub-pixel SP2. A pixel SP4 may be configured. The first pixel P1 may constitute one pixel. A bonding interval BP1 between one bonding pad 130 disposed on the first pixel P1 and one bonding pad 130 disposed on an adjacent pixel may be equal to the pixel interval PP1. The bonding interval BP1 may be approximately twice as large as the subpixel interval SPP1. In other words, if the first pixel P1 is connected to the driving layer 200 by the first bonding region, the bonding interval BP1 is at least the interval between the light emitting elements 111 or the interval between subpixels SPP1. can be bigger Also, since one bonding pad 130 is disposed per pixel, the bonding interval BP1 may be substantially equal to or greater than the interval PP1 between pixels. The bonding interval BP1 of the display layer 100 may be constant according to each pixel.

Referring to FIG. 2B , the 1' pixel p1 of the prior art display layer 1100 may include 1' to 4' light emitting devices (not shown). The 1' light emitting element generates the 1' sub-pixel sp1, the 2' light emitting element generates the 2' sub-pixel sp2, the 3' light emitting element generates the 3' sub-pixel sp3, The 'light emitting element may constitute the fourth' sub-pixel sp4 . The 1'th pixel p1 may constitute one pixel. The 1st' bonding pad of the 1st' sub-pixel sp1, the 2nd' bonding pad of the 2nd' sub-pixel Sp2, the 3rd' bonding pad of the 3' sub-pixel Sp3, and the 4th' sub-pixel A 4′ bonding pad may be located at (sp4). A bonding interval bp1 between the first and second bonding pads may be half the length of the pixel interval pp1. The bonding interval bp1 may be equal to the length of the sub-pixel interval spp1. The bonding interval BP1 of the display layer 100 according to the exemplary embodiment may be greater than the bonding interval bp1 of the conventional display layer.

The bonding distance between the switch control block 250 and the bonding area BP1 connected to the switch control block 250 to be described later is greater than the bonding distance BP1 between the bonding area BA0 of the display layer 100 including the light emitting element 111 above. can

The display device 10 according to an exemplary embodiment may include the display layer 100 and the driving layer 200 according to the above-described exemplary embodiment. The driving layer 200 may include a plurality of regions, and each region may correspond to each pixel of the display layer 100 as described above. An area of the driving layer 200 corresponding to the first pixel P1 of the display layer 100 may be referred to as a first area. A first bonding pad may be disposed on the first pixel P1 of the display layer 100 , and a first bonding pad corresponding to the first bonding pad may be disposed in the first region of the driving layer 200 . .

FIG. 3 is a conceptual diagram of a first pixel P1 and a first region of a display device 10 according to an exemplary embodiment, and FIG. 4 is a conceptual diagram of the display device 10 according to an exemplary embodiment. it did

Referring to FIG. 3 , the driving layer 200 of the display device 10 according to an exemplary embodiment may include a plurality of driving elements 210, and the driving element 210 applies at least one driving signal. can do. One driving element 210 may be allocated and disposed for each region of the driving layer 200 . For example, the first driving element disposed in the first region of the driving layer 200 is the first pixel P1 of the display layer 100 connected to the first region of the driving layer 200 through a first bonding region. A driving signal may be applied to the plurality of light emitting elements 111 included. That is, if one driving element 210 can apply a driving signal to a plurality of light emitting elements 111 and the plurality of light emitting elements 111 constitute one pixel, one driving element 210 can be used as one A driving signal may be applied to the pixels of One driving element 210 of the driving layer 200 and a plurality of light emitting elements 111 or a plurality of subpixels of one pixel of the display layer 100 may be electrically connected through the bonding area BA0. That is, the display device 10 may be configured to correspond to N light emitting elements 111 or M subpixels per driving element 210 (where N and M are integers greater than or equal to 1, and N is equal to M). or greater than M).

One driving element 210 of one region may include a transistor T1, a memory M1, and the like. At this time, the memory may be SRAM (Static Random Access Memory), but is not limited thereto and any memory is possible.

The display device according to the prior art with reference to FIG. 2A includes a plurality of driving elements to configure one pixel. For example, the driving layer 1200 includes three or more driving elements (not shown) corresponding to one pixel, and the three driving elements are three different bonding pad pairs 1130 and 1230 (or 3 One pixel was realized by driving three light emitting devices 1111 through three bonding regions, respectively. In such a conventional configuration, as the PPI increases, the spacing between the bonding pads 1130 (bonding interval) bp1 is relatively narrow, and the yield may decrease. In addition, since a plurality of driving elements must be disposed to form one pixel, manufacturing cost and time increase, and space between driving elements disposed in the driving layer 1200 may be further secured.

On the other hand, in the display device 10 according to the exemplary embodiment, one driving element 210 may drive a plurality of light emitting elements 111 through one bonding area BA0 to configure one pixel, and thus display a display device 10 according to an exemplary embodiment. During manufacturing, the yield may be relatively higher than that of the prior art. Driving the plurality of light emitting elements 111 with one driving element 210 may be referred to as sharing one driving element 210 by the plurality of light emitting elements 111 . By sharing the driving elements 210, it is possible to secure a space between the driving elements 210 disposed on the driving layer 200, and driving power, manufacturing cost, and manufacturing time of the display device 10 can also be reduced. In particular, the display device 10 according to an exemplary embodiment is an AR (Augmented Reality) and/or VR (Virtual Reality) display having a glasses or head-mounted structure requiring a high PPI, or a display thereof. It can be useful for devices that contain However, it is not limited thereto, and may be used for a lens type device or the like, and may also be used for a general micro LED display.

Referring to FIG. 3 , the display device 10 according to an exemplary embodiment may further include a plurality of switch control blocks 250 in the driving layer 200 . The plurality of switch control blocks 250 may control the switching elements 121 so that some of the driving signals transmitted from the driving element 210 to the plurality of light emitting elements 111 are allocated to each light emitting element 111. there is. Here, the switching element 121 may be a switching element 121 corresponding to each light emitting element 111 . That is, the driving signal may be a combination of signals corresponding to each light emitting element 111, and the plurality of switch control blocks 250 control the switching element 121 corresponding to each light emitting element 111 so that each A signal corresponding to each light emitting element 111 among driving signals coupled to the light emitting element 111 may be allocated. The plurality of switch control blocks 250 may include at least one connection line CL for connection with the plurality of switching elements 121 included in the switching layer 120 . Each connection line CL may extend from the switch control block 250 to the switching element 121 disposed on the switching layer 120 . The plurality of switch control blocks 250 may be connected to the plurality of switching elements 121 through the connection line CL, and each switching element 121 is controlled through the plurality of switch control blocks 250 to correspond to the switching elements 121. The light emitting element 111 may be operated.

The plurality of switch control blocks 250 may be included and/or disposed in the driving layer 200, and the plurality of switch control blocks 250 may be connected to the plurality of switching elements 121 included in the switching layer 120. can A bonding area BA1 may be disposed between the driving layer 200 and the display layer 100 to connect the plurality of switch control blocks 250 and the plurality of switching elements 121 . When the bonding pad pairs 131 and 230 are bonded, this may be referred to as a bonding area BA1. Each of the plurality of switch control blocks 250 may be connected to the display layer 100 through at least one pair of bonding pads 131 and 230 . Here, the bonding pad pair 131 and 230 may be the bonding pad 131 of the display layer 100 and the corresponding bonding pad 230 of the driving layer 200 corresponding to the bonding pad of the display layer 100 . The bonding pads 131 of the bonding pad pairs 131 and 230 may be bonding pads 131 for connecting the switch control block 250 and the display layer 100, which are the driving elements 210 and the display layer 100. ) can be distinguished from the bonding pad 130 for connection. That is, in addition to the bonding area BA0 disposed in the pixel, a bonding area BA1 for connecting the switch control block 250 and the display layer 100 may be formed and disposed. If the first pixel P1 of the display layer 100 includes a plurality of light emitting elements 111 or a plurality of subpixels, a bonding area BA1 for connecting one switch control block 250 and the display layer 100 ) may be arranged as many as the number of the plurality of light emitting elements 111 or the plurality of subpixels. For example, if the first pixel P1 of the display layer 100 includes four light emitting elements 111 and each constitutes one sub-pixel, 4 light emitting elements 111 are switched. The number of switching elements 121 may be disposed on the switching layer 120 . For connection between one switch control block 250 and the four switching elements 121, four bonding areas BA1 for connection between one switch control block 250 and the display layer 100 may be disposed. . A connection line CL may be disposed in each of the plurality of bonding areas BA1 , and each connection line CL may be disposed spaced apart from each other. For example, if the driving signal applied from one driving element 210 is a combination of the driving signals for the first to fourth light emitting elements, the driving signal corresponding to the first light emitting element is controlled by the first switch control block. It can be assigned to the first light emitting element through the first switching element. In addition, a driving signal corresponding to the second light emitting element may be allocated to the second light emitting element through the second switching element controlled by the second switch control block. The driving signals for the third light emitting element and the fourth light emitting element are the same. As in the previous exemplary embodiment, four bonding pads 131 may be disposed on the display layer 100 to connect the one switch control block 250 and the four switching elements 121, and the driving layer Four corresponding bonding pads 230 may be disposed at 200 . In the previous example, one switch control block 250 has been described to correspond to one pixel or one driving element 210, but one switch control block 250 need not correspond only to one driving element 210, and a plurality of It may correspond to the driving element 210 .

The spacing between the plurality of bonding areas BA1 disposed to connect the plurality of switch control blocks 250 and the display layer 100, that is, the bonding spacing may be substantially equal to or greater than the pixel distance, for example. there is. One of the plurality of switch control blocks 250 may be disposed to correspond to the plurality of driving elements 210 connected thereto. The plurality of switch control blocks 250 may be disposed over an area wider than one pixel at an end portion of a cross section of the display device 10 according to an exemplary embodiment. Since it may be disposed with a larger area than a pixel, the bonding interval between the bonding areas BA1 may be greater than the bonding interval between the bonding areas BA0 disposed in the pixel.

Referring to FIG. 4 , the driving layer 200 of the display device 10 according to an exemplary embodiment includes a data control block 270 including a plurality of column lines and a plurality of row lines. It may include a scan control block 290 including. One or more driving elements 210 may be disposed near each of a plurality of crossing points where a plurality of column lines and a plurality of row lines intersect. An area in which one or more driving elements 210 are disposed at one crossing point of the driving layer 200 may be one area of the driving layer 200 . For example, a first driving element disposed near the intersection of the first column line WL1 and the first row line BL1 and connected to the first column line WL1 and the first row line BL1 is disposed. The region may be a first region. For example, if the number of row lines is M (M is an integer greater than or equal to 1) and the number of column lines is N (N is an integer greater than or equal to 1), the driving layer 200 can be said to include M x N regions. , and may include M x N driving elements 210 . Here, the crossing point does not actually mean that the column line and the row line are in direct contact, but the driving element 210 is connected to one column line and one row line that cross each other, and receives data from one column line and is connected thereto. It can be referred to as a point where elements are operated or controlled.

In the display device 10 according to the exemplary embodiment, a plurality of light emitting devices 111 included in a plurality of pixels connected to the same row line are allocated respective driving signals by the same switch control block 250. can For example, the plurality of light emitting elements 111 included in the plurality of pixels connected to the first row line BL1 may be allocated respective driving signals by the first switch control block. If it is assumed that the first to Mth pixels receive corresponding driving signals from the first row line BL1, the first switching element of the first pixel (hereinafter referred to as the 1-1st switching element) and the second pixel 1 switching element (hereinafter referred to as 2-1 switching element), ... , M-1 th switching element may be connected to the first switch control block through the first connection line CL1 of the first switch control block. The first connection line CL1 may extend along the first to Mth pixels connected to the first row line BL1. In this case, the first light emitting element of the first pixel (hereinafter referred to as the 1-1 light emitting element) may be operated through the 1-1 switching element, and the second light emitting element of the second pixel (hereinafter referred to as the 2-1 light emitting element). light emitting element) may be operated through the 2-1st switching element. Similarly, the second switching element of the first pixel (hereinafter referred to as the 1-2nd switching element), the second switching element of the second pixel (the 2nd-2nd switching element), ... , the M-2th switching element It may be connected to the first switch control block through the second connection line CL2 of one switch control block. According to an exemplary embodiment, the number of row lines of the display device 10 and the number of switch control blocks 250 may be the same. However, it is not limited thereto, and the number of switch control blocks 250 and the number of row lines may be greater or less than the number of switch control blocks 250 .

A driving signal corresponding to each light emitting element 111 may be a time-sequentially separated driving signal applied from one driving element 210 . For example, assuming that the first pixel receives the first driving signal from the first driving element, the 1-1st light emitting element is the first when the 1-1st switching element is turned on by the first switch control block. Among the driving signals, only a signal corresponding to the 1-1 light emitting element may be applied. Similarly, the 1-2 light emitting devices may receive only the signal corresponding to the 1-2 light emitting devices among the first driving signals when the 1-2 switching devices are turned on by the first switch control block. The plurality of switching elements 121 may be turned on in time series, and the driving signal applied from the driving element 210 may be separated into different parts of the driving signal and applied to each light emitting element 111 in time series. there is. That is, according to the order in which the plurality of switching elements 121 are switched on, a driving signal corresponding to each light emitting element 111 may be sequentially applied to each light emitting element 111 .

M (M is an integer greater than or equal to 1) pixels connected to the first row line BL1 have M bonding areas BA0 for the M driving elements 210 . In addition, if four light emitting elements 111 form one pixel, there are four bonding areas BA1 for connecting the first switch control block and the display layer 100 . That is, the display device 10 may include M+4 bonding areas BA1 per row line. However, it is not limited to this, and if the number of light emitting elements 111 connected to each driving element 210 is not 4 but n _sp (n _sp is an integer greater than or equal to 1), the display device 10 is M+n per row line _sp bonding regions BA0 and BA1 may be included. If the number of column lines of the display device 10 is N (N is an integer greater than or equal to 1), the display device 10 has (M+n _sp )*N number of bonding areas BA0 and BA1. In the display device according to the related art with reference to FIG. 2A, for example, n _pr driving elements are disposed in one area, and n _pr (n _pr is an integer of 1 or more) light emitting elements 1111 corresponding thereto are disposed in the display layer If the number of pixels disposed in 1100 and connected to the first row line is M, n _pr *M bonding regions may be included per row line. If the number of column lines is N, the display device according to the prior art has n _pr *M*N bonding areas. This may be greater than the number of bonding areas BA0 and BA1 of the display device 10 according to the exemplary embodiment. That is, when the display device has the same size and number of pixels, the bonding distance BP1 of the display device 10 according to the exemplary embodiment is larger than that of the prior art display device, so that the yield can be increased.

5 shows a conceptual diagram of a display device 20 according to an exemplary embodiment.

Referring to FIG. 5 , one driving element 210 of a display device 20 according to an exemplary embodiment may apply a driving signal to two or more pixels, and one driving element 210 may implement two or more pixels. there is. For example, the six light emitting elements 111 included in the first pixel P1 and the second pixel P2 of FIG. 5 may receive a driving signal from the first driving element to realize two pixels. The plurality of light emitting elements 111 constituting the first pixel P1 and the second pixel P2 may receive a driving signal by one driving element 210, and one driving element 210 is disposed. The area of the driving layer 200 and the first pixel P1 and the second pixel P2 may be bonded through one bonding area BA0. That is, one bonding area BA0 may be disposed per two pixels, and in this case, the bonding interval may be approximately twice as large as when one bonding area BA0 is disposed per pixel. This configuration may be suitable for the display device 20 requiring a high PPI. The display device 20 according to an exemplary embodiment may further include a level shifter 215 in the driving element 210 . The switch control block 250 connected to the plurality of switching elements 121 of the first pixel P1 and the second pixel P2 transmits a driving signal to each of the first and second pixels P1 and P2. can be assigned to the light emitting element 111 of To this end, the switch control block 250 includes six connection lines CL1, CL2, CL3, CL4, CL5, CL6), and each of the six connection lines CL1, CL2, CL3, CL4, CL5, and CL6 connects the first pixel P1 and the second pixel P2 through six bonding areas BA1. It may be extended and connected to the switching element 121 . However, it is not limited thereto, and the plurality of light emitting devices 111 may implement three or more pixels. As several pixels are implemented through one drive element 210, a wide bonding interval can be secured, and thus, yield reduction in manufacturing a display can be reduced or prevented. However, as at least two or more pixels are implemented through one driving element 210, the number of bonding areas BA0 per pixel may be reduced, but arranged for connection between the switch control block 250 and the driving layer 200. The number of bonding areas BA1 may be increased. When forming the display, the display device 20 can be efficiently configured by appropriately considering this.

6 shows that the display device 10 according to an exemplary embodiment includes a color conversion layer 500 .

The display layer 100 of the display devices 10 and 20 according to the exemplary embodiments of FIGS. 1A to 5 may be passivated. In order for the display devices 10 and 20 to implement full color, each of the light emitting elements 111 emitting red (R), green (G) or blue (B) color light is transferred to one pixel and A fixing RGB display method may be used, and a method of using a color conversion layer in which the color conversion layer 500 is formed after transferring and fixing the light emitting elements 111 emitting blue (B) to all pixels may be used. In the case of the RGB display method, cross-sections of the display devices 10 and 20 may be configured similarly to those of FIG. ) can emit colored light. Referring to FIG. 6 , the color conversion layer 500 includes a first color conversion layer 510R that converts color light emitted from the first light emitting element into a first color and color light emitted from the second light emitting element into a second color. It may include a second color conversion layer 510G that converts light into a third color and a third color conversion layer 510B that converts color light emitted from the third light emitting device into a third color. For example, the first color may be red light, the second color may be green light, and the third color may be blue light. When the light emitting element emits blue light, the first color conversion layer 510R can convert blue light into red light, the second color conversion layer 510G can convert blue light into green light, and the third color conversion layer ( 510B) may be a layer including a resin that transmits blue light without color conversion. A barrier rib 530 may be disposed between the color conversion layers 510R, 501G, and 501B.

The display devices 10 and 20 described with reference to FIGS. 1A to 5 may be used in various electronic devices. In particular, the display devices 10 and 20 according to the exemplary embodiment are AR (Augmented Reality) and/or VR (Virtual Reality) displays having a glasses or head-mounted structure requiring a high PPI. Or it may be useful for a device including it. However, it is not limited thereto, and may be used for a lens type device or the like, and may also be used for a general micro LED display.

7 illustrates an example in which the display devices 10 and 20 according to an exemplary embodiment are applied to a mobile device. The mobile device 9100 may include a display device 9110 according to an exemplary embodiment. The display device 9110 may include the display devices 10 and 20 described with reference to FIGS. 1A to 5 . The display device 9110 may have a foldable structure and may be applied to, for example, a multi-folder display. Here, the mobile device 9100 is illustrated as a folder type display, but may also be applied to a general flat panel display.

8 illustrates an example in which the display devices 10 and 20 according to an exemplary embodiment are applied to a vehicle. The display devices 10 and 20 may be applied to a head-up display device for a vehicle. The head-up display device 9200 includes a display device 9210 provided in one area of the vehicle and at least one optical path changing member ( 9220) may be included.

9 illustrates an example in which display devices 10 and 20 according to an exemplary embodiment are applied to augmented reality glasses or virtual reality glasses. The augmented reality glasses 9300 may include a projection system 9310 that forms an image, and at least one element 9320 that guides the image from the projection system 9310 to enter the user's eyes. The projection system 9310 may include the display devices 10 and 20 described with reference to FIGS. 1A to 5 .

10 illustrates an example in which display devices 10 and 20 according to an exemplary embodiment are applied to a wearable display. The wearable display 9500 may include the display devices 10 and 20 described with reference to FIGS. 1A to 5 .

Display devices 10 and 20 according to exemplary embodiments may be applied to LED TVs, liquid crystal displays, mobile displays, smart watches, augmented reality (AR) glasses, virtual reality (VR) glasses, heads-up displays, signage, and the like. . In addition, it can be applied to various products such as rollable TVs and stretchable displays. In particular, it may be suitable for devices requiring high PPI.

The above embodiments are merely exemplary, and various modifications and equivalent other embodiments may be made therefrom by those skilled in the art. Therefore, the true technical scope of protection according to exemplary embodiments will have to be determined by the technical idea described in the following claims.

10,20: display device 100: display layer
110: light emitting layer 111: light emitting element
111a: first semiconductor layer 111b: active layer
111c: second semiconductor layer 113: ion implantation region
120: switching layer 121: switching element
130: bonding pad for driving element connection
131: bonding pad for connecting switch control block
200: driving layer
210: drive element 215: level shifter
230: bonding pad of drive layer 250: switch control block
270: data control block 290: scan control block
310: electrode 500: color conversion layer
530: bulkhead
P1: first pixel P2: second pixel
PP1: pixel spacing SP1 to SP4: first to fourth subpixels
SPP1: Sub-pixel spacing BP1: Bonding spacing
WL1: first column line BL1: first row line
T1: Transistor M1: Memory
CL: connection line CL1 to CL4: first to fourth connection lines
BA0: bonding area of a bonding pad for connecting a driving element and a bonding pad of a driving layer
BA1: bonding area of a bonding pad for connecting a switch control block and a bonding pad of a drive layer

Claims (20)

A display layer in which a plurality of light emitting elements and a plurality of switching elements corresponding to the plurality of light emitting elements one-to-one are grouped and arranged in pixel units, and the plurality of light emitting elements and the plurality of switching elements have a monolithic structure; and
A driving layer including a plurality of driving elements for applying at least one driving signal to the display layer; includes,
The display layer includes a plurality of pixels. According to claim 1,
The plurality of driving elements and the plurality of pixels correspond to each other on a one-to-one basis,
A display device in which the plurality of driving elements apply a driving signal corresponding to each of the plurality of pixels. According to claim 1,
The corresponding plurality of driving elements and the plurality of pixels are electrically connected by a plurality of bonding pad pairs disposed between the driving layer and the display layer. According to claim 3,
A distance between the plurality of bonding pad pairs is substantially equal to or greater than a distance between adjacent pixels of the display device. According to claim 3,
A distance between the plurality of bonding pad pairs is greater than a distance between adjacent light emitting elements of the display device. According to claim 1,
The plurality of pixels include a first pixel and a second pixel,
A first driving element among the plurality of driving elements applies a first driving signal to the first pixel and the second pixel. According to claim 1,
The plurality of pixels include a first pixel,
A first driving element among the plurality of driving elements applies a first driving signal to the first pixel;
Each of the plurality of light emitting elements disposed in the first pixel,
A display device receiving different portions of the first driving signal by a plurality of switching elements corresponding to each of the plurality of light emitting elements disposed in the first pixel. According to claim 7,
Different parts of the first driving signal are time-sequentially separated first driving signals,
The time-sequential separation is performed by sequential switching operations of the plurality of switching elements. According to claim 1,
The display layer includes a light emitting layer including the plurality of light emitting devices and
A switching layer disposed between the light emitting layer and the driving layer and including the plurality of switching elements;
A display device without a bonding layer between the light emitting layer and the switching layer. According to claim 1,
The driving layer,
and a plurality of switch control blocks controlling the plurality of switching elements so that different parts of the driving signal are allocated to the plurality of light emitting elements. According to claim 10,
The driving layer includes a data control block including a plurality of column lines and a scan control block including a plurality of row lines,
One driving element corresponding to one pixel among the plurality of pixels is connected to one column line among the plurality of column lines and one row line among the plurality of row lines;
The one low line corresponds to one switch control block among the plurality of switch control blocks,
Some of the plurality of light emitting elements are included in the plurality of pixels connected to the one row line,
A plurality of switching elements corresponding to some of the plurality of light emitting elements are controlled by the one switch control block. According to claim 11,
The one switch control block includes a plurality of connection lines,
The one switch control block is connected to the display layer through the same number of bonding pads as the number of light emitting elements included in the one pixel,
The plurality of connection lines extend along the plurality of pixels connected to the one row line and are connected to a plurality of switching elements corresponding to some of the plurality of light emitting elements included in the plurality of pixels connected to the first row line. . According to claim 12,
The plurality of pixels connected to the one row line include a first pixel and a second pixel,
One connection line among the plurality of connection lines,
A display device connected to a first switching element corresponding to a first light emitting element included in the first pixel and a second switching element corresponding to a second light emitting element included in the second pixel. According to claim 1,
At least one of the plurality of light emitting elements display device having a size of 0.1 um to 200 um. a plurality of light emitting elements; and
A plurality of switching elements corresponding to the plurality of light emitting elements one-to-one; are grouped and arranged in pixel units,
The plurality of light emitting elements and the plurality of switching elements have a monolithic structure,
A display layer including a plurality of pixels. According to claim 15,
The display layer includes a light emitting layer including the plurality of light emitting devices and
A switching layer including the plurality of switching elements,
A display layer without a bonding layer between the light emitting layer and the switching layer. According to claim 15,
The display layer further comprises a plurality of bonding pads corresponding to the plurality of pixels and disposed on one surface of the display layer. According to claim 17,
A distance between the plurality of bonding pads is substantially equal to or greater than a distance between adjacent pixels of the display layer. According to claim 17,
A distance between the plurality of bonding pads is substantially equal to or greater than a distance between adjacent light emitting elements of the display layer. According to claim 15,
At least one of the plurality of light emitting elements has a size of 0.1 um to 200 um display layer.

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