CN112991972B

CN112991972B - Display panel and transfer method of light-emitting device

Info

Publication number: CN112991972B
Application number: CN202110221151.XA
Authority: CN
Inventors: 何泽尚
Original assignee: Xiamen Tianma Microelectronics Co Ltd
Current assignee: Xiamen Tianma Microelectronics Co Ltd
Priority date: 2021-02-26
Filing date: 2021-02-26
Publication date: 2023-07-14
Anticipated expiration: 2041-02-26
Also published as: CN112991972A

Abstract

The embodiment of the invention discloses a display panel and a transfer method of a light-emitting device, wherein the display panel comprises the following components: a first driving circuit, a light emitting device, and a light sensing device; the first driving circuit comprises a first driving electrode and a first power line, the first driving electrode is electrically contacted with the light-emitting device through the first conductive bonding layer, and the first driving circuit is used for transmitting signals to the first driving electrode so as to enable the normal light-emitting device to emit light; the photosensitive device is electrically connected between the first power line and the first driving electrode and is used for being started when light emitted by the light emitting device is received, so that a first electric signal provided by the first power line is overlapped to the first driving electrode, and then the first conductive bonding layer is heated to bond the first driving electrode with the light emitting device. According to the embodiment of the invention, the bonding of the normal light emitting device and the first driving electrode can be realized, the abnormal detection of the light emitting device can be carried out, each pixel only needs to be provided with one light emitting device, PPI is improved, the cost is reduced, and the transfer and repair processes can be simplified.

Description

Display panel and transfer method of light-emitting device

Technical Field

The embodiment of the invention relates to the technical field of display, in particular to a transfer method of a display panel and a light-emitting device.

Background

With the development of display technology, more and more technical difficulties are solved. However, there are still many problems in repairing light emitting devices after transportation, and a solution is needed.

In the prior art of mass transfer of light emitting devices, a plurality of light emitting devices are generally configured in each pixel, after the light emitting devices are transferred to a substrate, each light emitting device is tested, if one of the light emitting devices is damaged, the electrical connection between the abnormal light emitting device and the substrate is cut off, and other light emitting devices configured in the pixel are adopted for replacement and repair, so that at least one light emitting device in each pixel is ensured to normally operate.

Obviously, the normal operation of at least one light emitting device in the pixels is ensured by arranging the backup light emitting devices, and the number of the light emitting devices in each pixel is increased by the mode, so that the improvement of the PPI of the display panel is limited, the cost is increased, and the follow-up detection and repair process is complicated.

Disclosure of Invention

The embodiment of the invention provides a display panel and a transfer method of a light-emitting device, which are used for reducing the bonding cost of the existing light-emitting device and a substrate and complicating subsequent detection and repair.

The embodiment of the invention provides a display panel, which comprises: a first driving circuit, a light emitting device, and a light sensing device;

The first driving circuit comprises a first driving electrode, the first driving electrode is electrically contacted with the light-emitting device through a first conductive bonding layer, and the first driving circuit is used for transmitting signals to the first driving electrode so as to enable the light-emitting device to emit light normally;

the first driving circuit further comprises a first power line, a first end of the photosensitive device is electrically connected to the first power line, a second end of the photosensitive device is electrically connected to the first driving electrode, the photosensitive device is used for being started when receiving light rays emitted by the light emitting device, a first electric signal provided by the first power line is enabled to be overlapped to the first driving electrode, and then the first conductive bonding layer is heated to enable the first driving electrode to be bonded with the light emitting device.

Based on the same inventive concept, embodiments of the present invention also provide a transfer method of a light emitting device for forming the display panel as described above, the transfer method including:

providing an array substrate, a plurality of light emitting devices and a transfer head, wherein a first driving circuit and a photosensitive device are formed on one side of the array substrate facing the transfer head, and the first driving circuit comprises a first driving electrode and a first power line;

Picking up a plurality of light emitting devices by adopting the transfer head, wherein a first conductive bonding layer is arranged on one side of the first driving electrode, which faces away from the array substrate, and/or a first conductive bonding layer is arranged on one side of the light emitting device, which faces towards the first driving electrode;

contacting the picked up plurality of light emitting devices with the first driving electrode through the first conductive bonding layer;

transmitting signals to the first driving electrode by adopting the array substrate, so that the light-emitting device emits light;

if the light emitting device emits light, the photosensitive device receives the light emitted by the light emitting device and is turned on, and a first electric signal provided by the first power line is applied to the first driving electrode through the photosensitive device, so that the first conductive bonding layer heats and melts, and the first driving electrode is bonded with the light emitting device.

In the embodiment of the invention, the first driving circuit transmits signals to the first driving electrode, so that the normal light emitting device emits light, and the abnormal light emitting device does not emit light, and the photosensitive device is started when receiving light emitted by the normal light emitting device, so that the first electric signal provided by the first power line is superposed on the first driving electrode, the current flowing through the first driving electrode and the first conductive bonding layer is increased, the first conductive bonding layer is heated and melted, and the normal light emitting device and the first driving electrode are bonded, and the abnormal light emitting device and the first driving electrode cannot be bonded. In the embodiment of the invention, the light-emitting device with normal functions can be bonded with the first driving electrode, so that the detection and identification of the abnormal light-emitting device are realized while bonding; only one light emitting device is needed to be configured for each pixel in the bonding process, so that the PPI is improved, the cost is reduced, and the repairing process is simplified; in addition, the state of the photosensitive device can be recovered after illumination, the performance is stable, the photosensitive device can be recycled, and the secondary detection can be realized after repair.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions of the prior art, a brief description will be given below of the drawings required for the embodiments or the description of the prior art, and it is obvious that although the drawings in the following description are specific embodiments of the present invention, it is obvious to those skilled in the art that the basic concepts of the device structure, the driving method and the manufacturing method, which are disclosed and suggested according to the various embodiments of the present invention, are extended and extended to other structures and drawings, and it is needless to say that these should be within the scope of the claims of the present invention.

Fig. 1 is a schematic structural diagram of a display panel according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of another display panel according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a micro led according to an embodiment of the present invention;

FIG. 4 is a schematic structural diagram of another display panel according to an embodiment of the present invention;

FIG. 5 is a schematic view of another micro LED according to an embodiment of the present invention;

fig. 6 is a schematic structural diagram of a first driving circuit according to an embodiment of the present invention;

Fig. 7 is a schematic structural diagram of another first driving circuit according to an embodiment of the present invention;

fig. 8 is a schematic structural diagram of a first driving circuit according to an embodiment of the present invention;

fig. 9 is a schematic structural diagram of a first driving circuit according to another embodiment of the present invention;

fig. 10 is a schematic structural diagram of a first driving circuit according to another embodiment of the present invention;

fig. 11 is a schematic structural diagram of a first driving circuit according to an embodiment of the present invention;

fig. 12 is a schematic diagram of a structure of a first driving circuit according to an embodiment of the present invention;

fig. 13 is a schematic structural view of a display panel according to another embodiment of the present invention;

FIG. 14 is a schematic view of a conductive bonding layer according to an embodiment of the present invention;

fig. 15 is a flowchart of a transfer method of a light emitting device according to an embodiment of the present invention;

fig. 16 is a schematic structural diagram of an array substrate and a light emitting device before bonding according to an embodiment of the present invention;

FIG. 17 is a schematic diagram of bonding a first driving electrode to a light emitting device according to an embodiment of the present invention;

fig. 18 is a schematic bonding diagram of a normal light emitting device and an abnormal light emitting device provided by an embodiment of the present invention;

fig. 19 is a flowchart of another method for transferring a light emitting device according to an embodiment of the present invention;

Fig. 20 is a schematic diagram of movement of a transfer head after bonding is completed according to an embodiment of the present invention.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be clearly and completely described by means of implementation examples with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, not all embodiments. All other embodiments obtained by those skilled in the art based on the basic concepts disclosed and suggested by the embodiments of the present invention are within the scope of the present invention.

The embodiment of the invention provides a display panel, which comprises: a first driving circuit, a light emitting device, and a light sensing device; the first driving circuit comprises a first driving electrode, the first driving electrode is electrically contacted with the light-emitting device through the first conductive bonding layer, and the first driving circuit is used for transmitting signals to the first driving electrode so as to enable the normal light-emitting device to emit light; the first driving circuit further comprises a first power line, the first end of the photosensitive device is electrically connected to the first power line, the second end of the photosensitive device is electrically connected to the first driving electrode, the photosensitive device is used for being started when receiving light emitted by the light emitting device, the first electric signal provided by the first power line is enabled to be overlapped to the first driving electrode, and then the first conductive bonding layer is heated to enable the first driving electrode to be bonded with the light emitting device.

In this embodiment, the first driving circuit transmits a signal to the first driving electrode to make the light emitting device emit light. The normal light-emitting device emits light, and the light is emitted to the corresponding photosensitive device to enable the photosensitive device to be started; the abnormal light emitting device does not emit light, and the corresponding photosensitive device is kept in an off state. After the photosensitive device is started, a first electric signal provided by the first power line flows through the started photosensitive device and enters the first driving circuit, the first electric signal is superposed to the first driving electrode, the current flowing through the first driving electrode is increased, the current flowing through the first driving electrode is transmitted to the light emitting device through the first conductive bonding layer, and therefore the photosensitive device is started to increase the current flowing through the first conductive bonding layer, the first conductive bonding layer is heated and melted, and normal bonding of the light emitting device and the first driving electrode is completed.

Similarly, when the abnormal light emitting device does not emit light, the photosensitive device is kept in an off state, so that the transmission path of the first electric signal and the first driving electrode is kept off, and then the current flowing through the first conductive bonding layer is a current signal for supporting the light emitting device to emit light, and self heating and melting cannot be realized, so that the first driving electrode and the abnormal light emitting device cannot be bonded.

In summary, bonding of the light emitting device and the first driving electrode can be achieved. Meanwhile, when bonding, the light emitting device capable of bonding with the first driving electrode is a normal light emitting device, and the light emitting device incapable of bonding with the first driving electrode is an abnormal light emitting device, and whether the light emitting device is abnormal or not can be judged obviously according to whether the light emitting device is bonded with the first driving electrode or not, so that detection and identification of the abnormal light emitting device can be realized while bonding, and a detection process is not required to be independently set after bonding.

In addition, each pixel is only provided with one light-emitting device, so that the PPI is improved and the cost is reduced; the state of the photosensitive device is recoverable after illumination, so that the photosensitive device has stable performance and can be recycled, the subsequent transferring and repairing processes can be simplified, and the secondary detection is realized after repairing.

The foregoing is the core idea of the present invention, and the following describes in detail the technical solution in the embodiment of the present invention with reference to the accompanying drawings in the embodiment of the present invention.

Exemplary, fig. 1 is a schematic structural diagram of a display panel according to an embodiment of the present invention, and as shown in fig. 1, the display panel includes: a first driving circuit 100, a light emitting device 200, and a light sensing device 300; the first driving circuit 100 includes a first driving electrode 110, the first driving electrode 110 is electrically contacted with the light emitting device 200 through the first conductive bonding layer 400, and the first driving circuit 100 is used for transmitting a signal to the first driving electrode 110 to make the normal light emitting device 200 emit light; the first driving circuit 100 further includes a first power line 120, a first end of the photosensitive device 300 is electrically connected to the first power line 120, and a second end of the photosensitive device 300 is electrically connected to the first driving electrode 110, the photosensitive device 300 is turned on when receiving the light emitted by the light emitting device 200, so that the first electric signal provided by the first power line 120 is superimposed on the first driving electrode 110, and then the first conductive bonding layer 400 is heated to bond the first driving electrode 110 and the light emitting device 200.

Specifically, referring to fig. 1, the display panel provided in the present embodiment includes a first driving circuit 100, a light emitting device 200, and a light sensing device 300, and the first driving circuit 100 includes a first driving electrode 110 and a first power line 120. In the bonding process, the first driving circuit 100 transmits a signal to the first driving electrode 110, the signal flows through the first driving electrode 100 and then flows through the first conductive bonding layer 400 electrically contacting both the first driving electrode 100 and the light emitting device 200 to drive the light emitting device 200, so that the normal light emitting device 200 emits light, and the light emitting device 200 having a damage or failure does not emit light.

The first terminal of the photosensitive device 300 is electrically connected to the first power line 120 in the first driving circuit 100, and the second terminal of the photosensitive device 300 is electrically connected to the first driving electrode 110 in the first driving circuit 100. When light emitted from the normal light emitting device 200 irradiates the light sensing device 300, the light sensing device 300 is turned on, and at this time, the first electric signal provided by the first power line 120 is superimposed on the first driving electrode 110 through the light sensing device 300, so that the current flowing through the first conductive bonding layer 400 is increased, and the first conductive bonding layer 400 is heated and melted, thereby completing the bonding of the normal light emitting device 200 and the first driving electrode 110.

Since the abnormal light emitting device 200 does not emit light under the driving of the first driving circuit 100, the light receiving device 300 corresponding to the abnormal light emitting device 200 is not in an off state, and the current flowing through the first conductive bonding layer 400 is insufficient to melt the same under the driving of the original signal, and thus the bonding of the abnormal light emitting device 200 and the first driving electrode 110 cannot be achieved. The abnormal light emitting device 200 can be subsequently transferred, and the transfer and repair of the light emitting device 200 can be carried out again on the position of the abnormal light emitting device 200, so that the abnormal light emitting device 200 is replaced by the normal light emitting device 200, and a display panel which can normally display all the light emitting devices 200 is obtained.

As can be seen from this, the bonding process of the light emitting device 200 and the first driving electrode 110 is achieved, and the abnormal light emitting device 200 can be identified, so that the detection process is simplified without using a detection circuit to detect the abnormality after the bonding is completed. In each bonding process, only one light emitting device 200 is required to be configured for each pixel, and backup light emitting devices are not required, so that the area of each pixel can be increased, or more pixels can be manufactured in a unit area, thereby improving PPI and reducing cost. In addition, since the state of the photosensitive device 300 after illumination is recoverable, that is, the photosensitive device is turned on when light is received and turned off when no light is received, the material is not denatured, and the photosensitive device can be turned off according to the light when being transferred again later, so that whether the transferred light-emitting device 200 works normally or not can be identified in the repairing process, the performance is stable, the light-emitting device can be recycled, and the following transferring and repairing processes can be simplified.

It should be noted that, the structure and the position of the first conductive bonding layer 400 are not limited in the embodiment of the invention, and may be set by those skilled in the art according to the actual situation. The first conductive bonding layer 400 may have a single-layer structure, and the first conductive bonding layer 400 may be bonded to the first driving electrode 110 or the light emitting device 200; alternatively, the first conductive bonding layer 400 has a double-layered structure and is disposed on the surfaces of the first driving electrode 110 and the light emitting device 200, respectively, to enhance the bonding effect. The material of the first conductive bonding layer 400 is not particularly limited in the embodiments of the present invention on the basis of ensuring that bonding is achieved by heating and melting.

Optionally, the first driving circuit further includes a second driving electrode, the first driving electrode is electrically contacted with the light emitting device through the first conductive bonding layer, and the second driving electrode is electrically contacted with the light emitting device through the second conductive bonding layer; the first driving circuit is used for transmitting signals to the first driving electrode and the second driving electrode to enable the normal light-emitting device to emit light.

Fig. 2 is a schematic structural diagram of another display panel according to an embodiment of the present invention, and as shown in fig. 2, the first driving circuit 100 includes a first driving electrode 110 and a second driving electrode 130 that are disposed in an insulated manner, the first driving electrode 110 and the second driving electrode 130 are located on the same side of the light emitting device 200 and are electrically contacted with the light emitting device 200 through a first conductive bonding layer 400 and a second conductive bonding layer 500, respectively. The first driving circuit 100 transmits signals to the first driving electrode 110 and the second driving electrode 130, respectively, to drive the light emitting device 200 to operate, so that the normal light emitting device 200 emits light. In this embodiment, by arranging the first driving electrode 110 and the second driving electrode 130 on the same side of the light emitting device 200, the first driving electrode 110 and the second driving electrode 130 share one driving circuit, i.e. the first driving circuit 100, so that the process can be simplified and the cost can be reduced.

Alternatively, the light emitting device 200 includes the first and

second electrodes

210 and 230 and the light emitting layer 220 between the first and

second electrodes

210 and 230, and the first and

second electrodes

210 and 230 of the light emitting device 200 are located at the same side of the light emitting layer 220; the first driving electrode 110 is electrically contacted with the first electrode 210 through the first conductive bonding layer 400, and the second driving electrode 130 is electrically contacted with the second electrode 230 through the second conductive bonding layer 500.

With continued reference to fig. 2, the light emitting device 200 may be provided in a ipsilateral electrode structure on the basis of the above-described embodiments. Specifically, the light emitting device 200 includes a first electrode 210, a light emitting layer 220, and a second electrode 230, and the first electrode 210 and the second electrode 230 are positioned on the same side of the light emitting layer 220, wherein the first electrode 210 and the second electrode 230 are positioned on a side of the light emitting layer 220 facing the first driving electrode 110. The first driving electrode 110 is electrically contacted with the first electrode 210 of the light emitting device 200 through the first conductive bonding layer 400, and the second driving electrode 130 is electrically contacted with the second electrode 230 of the light emitting device 200 through the second conductive bonding layer 500. The first driving circuit 100 transmits signals to the first driving electrode 110 and the second driving electrode 130, respectively, and controls the light emitting device 200 in common through the first conductive bonding layer 400 and the second conductive bonding layer 500, which are in contact with the first driving electrode 110 and the second driving electrode 130, respectively, so that the normal light emitting device 200 emits light. For example, the first electrode 210 is a cathode and the second electrode 230 is an anode, the first driving circuit 100 may apply a negative voltage to the first driving electrode 110, and the first driving circuit 100 may apply a positive voltage to the second driving electrode 130, so that the normal light emitting device 200 emits light.

The light sensing device 300 is turned on when receiving light emitted from the normal light emitting device 200, so that a first electrical signal provided from a first power line (not shown) in the first driving circuit 100 is superimposed on the first driving electrode 110, thereby increasing current flowing through the first conductive bonding layer 400 and the second conductive bonding layer 500, respectively heating and melting the first conductive bonding layer 400 and the second conductive bonding layer 500, thereby bonding the first electrode 210 to the first driving electrode 110 through the first conductive bonding layer 400, and bonding the second electrode 230 to the second driving electrode 130 through the second conductive bonding layer 500. The first electrode 210 of the light emitting device 200 may be an anode or a cathode, and the second electrode 230 may be a cathode or an anode, respectively, which is not limited in the embodiment of the present invention.

Fig. 3 is a schematic structural diagram of a micro light emitting diode according to an embodiment of the present invention, and as shown in fig. 3, an optional light emitting device 200 is a micro light emitting diode; the light emitting layer 220 includes a first type semiconductor layer 221, an active layer 222, and a second type semiconductor layer 223, which are sequentially stacked; the first electrode 210 is located at a side of the first type semiconductor layer 221 facing the active layer 222, and the second electrode 230 is located at a side of the second type semiconductor layer 223 facing away from the active layer 222. The size of the Micro light emitting diode (Micro Light Emitting Diode, abbreviated as Micro LED) is in a micron level, and a display panel adopting the Micro LED has the characteristics of independent control of pixels, independent light emitting control, high brightness, low power consumption, ultrahigh resolution, high color saturation and the like, and has become a hot spot for developing future display technologies.

The micro light emitting diode includes a first electrode 210, a light emitting layer 220, and a second electrode 230, and the light emitting layer 220 includes a first type semiconductor layer 221, an active layer 222, and a second type semiconductor layer 223, which are sequentially stacked. The first electrode 210 and the second electrode 230 are located on the same side of the light emitting layer 220. Specifically, the first electrode 210 and the second electrode 230 are fabricated by etching the first type semiconductor layer 221 and the active layer 222 to expose a portion of the first type semiconductor layer 221, fabricating the first electrode 210 on a surface of the exposed first type semiconductor layer 221 facing the active layer 222, and fabricating the second electrode 230 on a side of the second type semiconductor layer 223 facing away from the active layer 222, thereby forming the micro light emitting diode with the same side electrode structure. The materials of the first type semiconductor layer 221, the active layer 222, and the second type semiconductor layer 223 are not limited, and a person skilled in the art may select a corresponding material according to the emission color of the light emitting device 200.

Optionally, the display panel includes a first substrate 1 and an array layer 2 located on one side of the first substrate 1; the first driving circuit 100 and the photosensitive device 300 are positioned on the array layer 2, and the light emitting device 200 is positioned on one side of the array layer 2 away from the first substrate 1; the first driving electrode 110, the second driving electrode 130, the first electrode 210, and the second electrode 230 are transparent electrodes.

Referring to fig. 2, the display panel in this embodiment includes a first substrate 1, an array layer 2, and a light emitting device 300 sequentially disposed, and the first driving circuit 100 and the light sensing device 300 are both located in the array layer 2. Light emitted from the light emitting layer 220 of the light emitting device 200 passes through the first (or second) electrode, the first (or second) conductive bonding layer, and the first (or second) driving electrode to enter the photosensitive device 300, so that each film layer disposed between the light emitting layer 220 and the photosensitive device 300 is a transparent film layer. For example, the first driving electrode 110 and the second driving electrode 130 in the first driving circuit 100, and the first electrode 210 and the second electrode 230 of the light emitting device 200 are transparent electrodes, so that light emitted by the light emitting device 200 is not blocked by the electrodes and can be emitted to the photosensitive device 300, current flowing through the first driving electrode 110 is increased, and the conductive bonding layer is heated and melted, so that bonding between the light emitting device 200 and the first driving electrode 110 and the second driving electrode 130 is realized. The materials of the first driving electrode 110, the second driving electrode 130, the first electrode 210, and the second electrode 230 are not limited, and may be, for example, indium Tin Oxide (ITO).

Fig. 4 is a schematic structural diagram of still another display panel according to an embodiment of the present invention, and as shown in fig. 4, optionally, the display panel further includes a second driving circuit 600, where the second driving circuit 600 includes a second driving electrode 610, and the second driving electrode 610 is electrically contacted with the light emitting device 200; the first driving circuit 100 transmits a signal to the first driving electrode 110, and the second driving circuit 600 transmits a signal to the second driving electrode 610, so that the normal light emitting device 200 emits light.

The display panel in this embodiment includes a first driving circuit 100 and a second driving circuit 600, the first driving circuit 100 includes a first driving electrode 110, and the second driving circuit 600 includes a second driving electrode 610. The first driving electrode 110 and the second driving electrode 610 may be positioned at opposite sides of the light emitting device 200, the first driving electrode 110 may be in electrical contact with the light emitting device 200 through the first conductive bonding layer 400, and the second driving electrode 610 may be in direct electrical contact with the light emitting device 200. In operation, the first driving circuit 100 and the second driving circuit 600 transmit different signals to the first driving electrode 110 and the second driving electrode 130, respectively, so as to drive the light emitting device 200, and make the normal light emitting device 200 emit light.

Alternatively, the light emitting device 200 includes first and

second electrodes

210 and 230 and a light emitting layer between the first and second electrodes 210 and 30, the first and

second electrodes

210 and 230 of the light emitting device 200 being located at opposite sides of the light emitting layer 220; the first driving electrode 100 is electrically contacted with the first electrode 210 through the first conductive bonding layer 400, and the second driving electrode 600 is electrically contacted with the second electrode 230.

With continued reference to fig. 4, the light emitting device 200 may be provided in a vertical structure on the basis of the above-described embodiments. Specifically, the light emitting device 200 includes a first electrode 210, a light emitting layer 220, and a second electrode 230, which are sequentially stacked. The first driving electrode 110 is electrically contacted with the first electrode 210 of the light emitting device 200 through the first conductive bonding layer 400, and the second driving electrode 610 is electrically contacted with the second electrode 230 of the light emitting device 200. In the bonding process, the first driving circuit 100 and the second driving circuit 600 respectively transmit different signals to the first driving electrode 110 and the second driving electrode 610, so that the normal light emitting device 200 emits light. The light sensing device 300 is turned on when receiving light emitted from the normal light emitting device 200, so that a first electrical signal provided from a first power line (not shown) in the first driving circuit 100 is superimposed on the first driving electrode 110, and a current flowing through the first conductive bonding layer 400 in contact with the first driving electrode 110 is increased, so that the first conductive bonding layer 400 is heated and melted, and the first electrode 210 is bonded with the first driving electrode 110 through the first conductive bonding layer 400. The first electrode 210 of the light emitting device 200 may be an anode or a cathode, and the second electrode 230 may be a cathode or an anode, respectively, without limitation.

Fig. 5 is a schematic structural diagram of another micro led according to an embodiment of the present invention, and as shown in fig. 5, the light emitting device 200 is an optional micro led; the light emitting layer 220 includes a first type semiconductor layer 221, an active layer 222, and a second type semiconductor layer 223, which are sequentially stacked; the first electrode 210 is located at a side of the first type semiconductor layer 221 facing away from the active layer 222, and the second electrode 230 is located at a side of the second type semiconductor layer 223 facing away from the active layer 222. The micro light emitting diode includes a light emitting layer 220, and a first electrode 210 and a second electrode 230 disposed on opposite sides of the light emitting layer 220, wherein the light emitting layer 220 includes a first type semiconductor layer 221, an active layer 222, and a second type semiconductor layer 223 sequentially stacked. The specific materials of each film layer in the light-emitting layer 220 are not limited in this embodiment.

Optionally, the display panel includes a first substrate 1 and a second substrate 3 opposite to each other; the first driving circuit 100 and the photosensitive device 300 are positioned at a side of the first substrate 1 facing the second substrate 3, the second driving circuit 600 is positioned at a side of the second substrate 2 facing the first substrate 1, and the light emitting device 200 is positioned between the first substrate 1 and the second substrate 3; the first driving electrode 110 and the first electrode 210 are transparent electrodes, and the second driving electrode 610 and the second electrode 230 are reflective electrodes.

Referring to fig. 4, the display panel in the present embodiment includes a first substrate 1, a first driving circuit 200, a light emitting device 200, a second driving circuit 600, and a second substrate 3, which are sequentially disposed. The first driving electrode 110 and the first electrode 210 disposed between the light emitting layer 220 and the photosensitive device 300 are transparent electrodes, so that light emitted from the light emitting device 200 is not blocked by the electrodes and can be emitted to the photosensitive device 300. Further, at least one of the second driving electrode 610 and the second electrode 230 disposed between the light emitting layer 220 and the second substrate 3 is a reflective electrode, and the reflective electrode may reflect light emitted from the light emitting device 200, so that more light is irradiated to the light sensing device 300, and the light energy utilization rate is improved. By adopting the above scheme, the current flowing through the light emitting device 200 can be increased, so that the first conductive bonding layer 400 contacted with the light emitting device 200 is heated and melted, bonding between the light emitting device 200 and the first driving electrode 110 is realized, and the transfer efficiency is improved. The materials of the second driving electrode 610 and the second electrode 230 are not limited, and for example, a metal with high reflectivity may be used as long as the light emitted from the light emitting device 200 can be reflected.

Fig. 6 is a schematic structural diagram of a first driving circuit according to an embodiment of the present invention, and referring to fig. 6, optionally, a first end of a photosensitive device 300 is electrically connected to a first power line 120 through a first photosensitive switch 301; the first driving circuit 100 further includes a first gate line Scan1, where the first gate line Scan1 is electrically connected to the control terminal of the first photosensitive switch 301, and is used to control the first photosensitive switch 301 to be turned on or off; the operation of the display panel includes a bonding stage in which the first photosensitive switch 301 is turned on and a non-bonding stage in which the first photosensitive switch 301 is turned off.

A first photosensitive switch 301 is disposed between the first power line 120 and the first end of the photosensitive device 300, a control end of the first photosensitive switch 301 is electrically connected to a first gate line Scan1 in the first driving circuit 100, and the first driving circuit 100 controls on or off of the first photosensitive switch 301 through the first gate line Scan 1.

In the bonding stage, the first driving circuit 100 controls the first photosensitive switch 301 to be turned on through the first gate line Scan1, and a path is formed between the first power line 120 and the first end of the photosensitive device 300. If the photosensitive device 300 is turned on, the first electrical signal provided by the first power line 120 may be applied to the first driving electrode 110 through the turned-on first photosensitive switch 301 and the photosensitive device 300, and the first conductive bonding layer 400 is heated, so that the first driving electrode 110 is bonded to the normal light emitting device 200. The optional bonding stage is a detection stage before shipping.

In the non-bonding stage, the first driving circuit 100 controls the first photosensitive switch 301 to be turned off through the first gate line Scan1, and cuts off the path between the first power line 120 and the first end of the photosensitive device 300, so that the photosensitive device 300 is no longer involved in the operation of the display panel. The optional non-bonding stage is a display stage, and when the first photosensitive switch 301 is turned off, the photosensitive device 300 is no longer involved in the operation of the display panel, so that the interference of the first electrical signal provided by the first power line 120 on the brightness of the light emitting device 200 in the display stage can be avoided, and normal display can be realized.

Fig. 7 is a schematic diagram of another first driving circuit according to an embodiment of the present invention, and referring to fig. 7, optionally, a second end of the photosensitive device 300 is electrically connected to the first driving electrode 110 through a second photosensitive switch 302; the first driving circuit 100 further includes a second gate line Scan2, where the second gate line Scan2 is electrically connected to the control terminal of the second photosensitive switch 302, and is used to control the second photosensitive switch 302 to be turned on or off; the operation of the display panel includes a bonding stage in which the second photosensitive switch 302 is turned on and a non-bonding stage in which the second photosensitive switch 302 is turned off.

A second photosensitive switch 302 is disposed between the second end of the photosensitive device 300 and the first driving electrode 110, a control end of the second photosensitive switch 302 is electrically connected to a second gate line Scan2 in the first driving circuit 100, and the first driving circuit 100 controls the second photosensitive switch 302 to be turned on or off through the second gate line Scan 2.

In the bonding stage, the first driving circuit 100 controls the second photosensitive switch 302 to be turned on through the second gate line Scan2, and a path is formed between the second end of the photosensitive device 300 and the first driving electrode 110. If the photosensitive device 300 is turned on, the first electrical signal provided by the first power line 120 may be superimposed on the first driving electrode 110 through the turned-on photosensitive device 300 and the second photosensitive switch 302, and heat the first conductive bonding layer 400, so as to bond the first driving electrode 110 with the normal light emitting device 200. The optional bonding stage is a detection stage before shipping.

In the non-bonding stage, the first driving circuit 100 controls the second photosensitive switch 302 to be turned off through the second gate line Scan2, and cuts off the path between the first power line 120 and the second end of the photosensitive device 300, so that the photosensitive device 300 is no longer involved in the operation of the display panel. The optional non-bonding stage is a display stage, and when the second photosensitive switch 302 is turned off, the photosensitive device 300 is no longer involved in the operation of the display panel, so that the interference of the first electrical signal provided by the first power line 120 on the brightness of the light emitting device 200 in the display stage can be avoided, and the display effect is prevented from being affected.

Optionally, the first driving circuit 100 includes a pixel circuit 140, and the pixel circuit 140 includes a driving module 141 and a light emission control module 142; the driving module 141 is used for providing driving current for the light emitting device 200; the light emitting control module 142 is connected in series between the driving module 141 and the light emitting device 200, the light emitting control module 142 includes a first driving electrode, and the light emitting control module 142 is used for controlling whether a driving current flows through the first driving electrode and the light emitting device 200.

The pixel circuit 140 includes a driving module 141 and a light emitting control module 142, the light emitting control module 142 includes a first driving electrode, and the light emitting control module 142 is connected in series between the driving module 141 and the light emitting device 200. The driving module 141, the light emission control module 142, and the light emitting device 200 form a transmission path of the driving current. Specifically, the driving module 141 provides a constant driving current signal to the light emitting device 200, and controls whether the driving current signal flows through the first driving electrode and the light emitting device 200 under the switching of the on or off state of the transistor (T7 in the drawing) in the light emitting control module 142, thereby controlling whether the light emitting device 200 emits light.

Optionally, the second end of the photosensitive device 300 is electrically connected to the first driving electrode through the driving module 141. The second end of the light sensing device 300 is electrically connected to the first driving electrode in the light emitting control module 142 through the driving module 141, thereby forming a first electric signal transmission path including the first power line 120, the light sensing device 300, the driving module 141, the light emitting control module 142 (first driving electrode), and the light emitting device 200.

When bonding, the photosensitive device 300 receives the light emitted from the light emitting device 200 and is turned on, the first electrical signal provided by the first power line 120 flows through the first driving electrode and the light emitting device 200 through the paths, and the first electrical signal is overlapped with the driving current signal provided by the driving module 141, so that the current flowing through the first driving electrode and the light emitting device 200 is increased, and the first conductive bonding layer 400 contacted with the first driving electrode is heated and melted, thereby completing bonding.

Optionally, the driving module 141 includes a driving transistor T3, where the driving transistor T3 includes a gate, a first end, and a second end; the second terminal of the photosensitive device 300 is electrically connected to the gate of the driving transistor T3, or the second terminal of the photosensitive device 300 is electrically connected to the first terminal of the driving transistor T3, or the second terminal of the photosensitive device 300 is electrically connected to the second terminal of the driving transistor T3.

The driving module 141 includes the driving transistor T3 as an example. Specifically, the second terminal of the photosensitive device 300 may be electrically connected to any one of the gate, the first terminal, and the second terminal of the driving transistor T3.

Fig. 8 is a schematic diagram of a first driving circuit according to an embodiment of the present invention, where a second terminal of the photosensitive device 300 shown in fig. 8 is electrically connected to a first terminal of the driving transistor T3, and the first terminal of the driving transistor T3 is an output terminal of the driving transistor T3. As shown in fig. 6 and 8, when the second terminal of the photosensitive device 300 is connected to the first terminal of the driving transistor T3, the first electrical signal provided by the first power line 120 is superimposed on the driving current signal provided by the driving module 141 through the turned-on photosensitive device 300, so that the current flowing through the first driving electrode and the light emitting device 200 is increased, and the bonding of the first driving electrode and the light emitting device 200 is achieved. In other embodiments, the second terminal of the photosensitive device is also optionally electrically connected to the input terminal of the drive transistor.

Referring to fig. 6, when the second terminal of the photosensitive device 300 is connected to the gate electrode of the driving transistor T3, in the bonding stage, the first electrical signal provided by the first power line 120 is applied to the gate electrode of the driving transistor T3 through the turned-on photosensitive device 300, so that the threshold voltage of the driving transistor T3 is reduced, and the driving current signal flowing through the driving transistor T3 is increased, thereby increasing the current flowing through the first driving electrode and the light emitting device 200 to heat and melt the first conductive bonding layer between the first driving electrode and the light emitting device 200, and bonding the first driving electrode and the light emitting device 200 is achieved.

Alternatively, the second end of the photosensor 300 is electrically connected to the first driving electrode through the light emission control module 141.

Fig. 9 is a schematic structural diagram of still another first driving circuit according to an embodiment of the present invention, and as shown in fig. 9, a second end of the photosensitive device 300 is electrically connected to a first driving electrode through the light emitting control module 142, so as to form a first electric signal transmission path including the first power line 120, the photosensitive device 300, the light emitting control module 142 (first driving electrode) and the light emitting device 200.

Optionally, the light-emitting control module 142 includes a first light-emitting control transistor T7, the first light-emitting control transistor T7 is connected in series between the driving module 141 and the first driving electrode, and the first light-emitting control transistor T7 includes a gate electrode, a first end and a second end; the second terminal of the light sensing device 300 is electrically connected to the gate of the first light emitting control transistor, or the second terminal of the light sensing device 300 is electrically connected to the first terminal of the first light emitting control transistor, or the second terminal of the light sensing device 300 is electrically connected to the second terminal of the first light emitting control transistor.

In other embodiments, the optional light emission control module further includes a second light emission control transistor T1, the second light emission control transistor T1 including a gate, a first terminal, and a second terminal; the second terminal of the light sensing device 300 is electrically connected to the gate of the second light emission control transistor T1, or the second terminal of the light sensing device is electrically connected to the first terminal of the second light emission control transistor T1, or the second terminal of the light sensing device is electrically connected to the second terminal of the second light emission control transistor T1.

The first light emitting control transistor is exemplified by T7. Specifically, the second terminal of the light sensing device 300 may be electrically connected to any one of the gate electrode, the first terminal, and the second terminal of the first light emitting control transistor T7.

Fig. 10 is a schematic diagram of a structure of a first driving circuit according to an embodiment of the present invention, where a second end of the photosensitive device 300 shown in fig. 10 is electrically connected to a first end of the first light emitting control transistor T7, and the first end of the first light emitting control transistor T7 is optionally an output end of the first light emitting control transistor T7. As shown in fig. 10, when the second terminal of the photosensor 300 is connected to the first terminal of T7, the first electrical signal provided by the first power line 120 is superimposed on the driving current signal provided by the driving module 141 through the turned-on photosensor 300, thereby increasing the current flowing through the first driving electrode and the light emitting device 200, and bonding the first driving electrode and the light emitting device 200 is achieved. In other embodiments, the second terminal of the optional photosensitive device is electrically connected to the input terminal of the first light emitting control transistor T7.

Referring to fig. 9, when the second terminal of the photosensitive device 300 is connected to the gate electrode of T7, in the bonding stage, the first electrical signal provided by the first power line 120 is applied to the gate electrode of T7 through the turned-on photosensitive device 300, so that the threshold voltage of T7 can be reduced, and thus the current flowing into the first driving electrode and the light emitting device 200 is increased, and the first conductive bonding layer between the first driving electrode and the light emitting device 200 is heated and melted, thereby bonding the first driving electrode and the light emitting device 200.

Fig. 11 is a schematic diagram of a first driving circuit according to an embodiment of the present invention, and as shown in fig. 11, the pixel circuit 140 is optionally electrically connected to a reference voltage line Vref, and the reference voltage line Vref is used to provide a reference voltage signal to the pixel circuit 140; the reference voltage line Vref is multiplexed as the first power line 120. As shown in fig. 11, in this embodiment, the reference voltage line Vref for providing the reference voltage signal to the pixel circuit 140 is multiplexed to the first power line 120, that is, the reference voltage line Vref is set to provide the first electrical signal, and the first electrical signal is provided by using the existing signal line in the pixel circuit 140, so that the process can be simplified without separately setting the first power line 120.

Fig. 12 is a schematic diagram of a structure of a first driving circuit according to an embodiment of the present invention, and as shown in fig. 12, the pixel circuit 140 is optionally electrically connected to a low-level signal line Vee, where the low-level signal line Vee is used to provide a low-level signal to the pixel circuit 140; the low-level signal line Vee is multiplexed as a first power supply line. Referring to fig. 12, in this embodiment, the low-level signal line Vee for providing the low-level signal to the pixel circuit 140 is multiplexed to the first power line 120, that is, the low-level signal line Vee is set to provide the first electrical signal, and the existing signal line in the pixel circuit 140 is used to provide the first electrical signal, so that the process can be simplified without separately setting the first power line 120.

Fig. 13 is a schematic structural diagram of a display panel according to an embodiment of the present invention, and as shown in fig. 13, optionally, the display panel includes: a substrate 101; an array layer 2 located at one side of the substrate 101, the array layer 2 including a pixel circuit structure layer 21 and a photosensitive device structure layer 22, the pixel circuit structure layer 21 including an active layer 102, a gate insulating layer 103, a gate metal layer 104, an interlayer insulating layer 105 and a source drain metal layer 106, the photosensitive device structure layer 22 including a photosensitive PN junction 201 and a positive and negative electrode layer 202; a drive electrode layer on the side of the array layer 2 facing away from the substrate 101, the drive electrode layer comprising at least one first drive electrode 110.

The display panel comprises a substrate base 101, an array layer 2 and a driving electrode layer positioned on the array layer 2, wherein the array layer 2 comprises a pixel circuit structure layer 21 formed by an active layer 102, a gate insulating layer 103, a gate metal layer 104, an interlayer insulating layer 105 and a source drain metal layer 106, and a photosensitive device structure layer 22 formed by a photosensitive PN junction 201 and a positive electrode layer 202. The number of first driving electrodes 110 in the driving electrode layer corresponds to the number of light emitting devices 200 in the display panel, i.e., one light emitting device 200 corresponds to one first driving electrode 110, and the driving electrode layer controls the light emitting device 200 in electrical contact with the corresponding first driving electrode 110.

Optionally, the photosensitive PN junction 201 of the photosensitive device structure layer 22 is the same layer as the active layer 102 of the pixel circuit structure layer 21.

Referring to fig. 13, the photosensitive PN junction 201 of the photosensitive device structure layer 22 in this embodiment may be disposed in the same layer as the active layer 102 in the pixel circuit structure layer 21, and the photosensitive PN junction 201 of the photosensitive device structure layer 22 is disposed in the same layer on the basis of the existing film layer in the pixel circuit 140, so that the thickness of the display panel is not increased and the cost is reduced without independently increasing the film layer of the photosensitive device structure layer 22. In other embodiments, the photosensitive PN junction 201 may be separately disposed, and the photosensitive PN junction 201 and the active layer 102 may be located in different layers.

Optionally, the positive and negative electrode layer 202 of the photosensitive device structure layer 22 is co-layer with the gate metal layer 104 of the pixel circuit structure layer 21; alternatively, the positive and negative electrode layers 202 of the photosensitive device structure layer are the same layer as the source and drain metal layers 106 of the pixel circuit structure layer; alternatively, the positive and negative electrode layers 202 of the photosensor structural layer 22 are the same layer as the drive electrode layer 1.

The position of the positive and negative electrode layers 202 in the photosensitive device structure layer 22 is not limited in the embodiment of the present invention, and may be selected and set by those skilled in the art according to design requirements. Referring to fig. 13, the positive and negative electrode layers 202 of the photosensitive device structure layer 22 and the gate metal layer 104 are provided as the same layers, but not limited to, the photosensitive PN junction 201 of the photosensitive device structure layer 22 and the active layer 102 are provided as an example. Specifically, the positive and negative electrode layers 202 of the photosensitive device structure layer 22 and the gate metal layer 104 are arranged in the same layer, and share one mask, and the positive and negative electrode layers 202 are electrically connected with the photosensitive PN junction 201 in the active layer 102 through the via hole in the gate insulating layer 103. The positive and negative electrode layers 202 of the photosensor structure layer 22 are arranged on the same layer on the basis of the existing film layer in the pixel circuit 140, and the film layer of the photosensor structure layer 22 does not need to be independently added, so that the thickness of the display panel is not increased, and the cost can be reduced.

In other embodiments, the positive and negative electrode layers 202 of the photosensitive device structure layer 22 may also be disposed with the source and drain metal layers 106 in the pixel circuit structure layer, or with the driving electrode layer.

Optionally, the film layer on the side of the photosensitive PN junction 202 facing away from the substrate 101 is a transparent film layer; in a direction perpendicular to the substrate base 101, the front projection of the photosensitive PN structure 202 at least partially overlaps the front projection of the light emitting device 200.

Referring to fig. 13, a film layer on a side of the photosensitive PN junction 202 away from the substrate 101, for example, the gate insulating layer 103, the gate metal layer 104, the interlayer insulating layer 105, the source drain metal layer 106 and the driving electrode layer 1 may be all transparent film layers, so that light emitted by the light emitting device 200 may directly penetrate through the transparent film layers and irradiate the photosensitive PN junction 202, so as to increase the speed of receiving light by the photosensitive PN structure 202, thereby starting the photosensitive device 300, increasing the current flowing through the first driving electrode 110, increasing the melting speed of the first conductive bonding layer 400 contacting with the first driving electrode 110, and further improving the transfer efficiency of the light emitting device 200.

In addition, the orthographic projection of the photosensitive PN structure 202 on the substrate 101 and the orthographic projection of the light emitting device 200 on the substrate 101 may be partially overlapped or fully overlapped, so as to increase the overlapping area of the photosensitive PN structure 202 and the light, further increase the speed of receiving the light by the photosensitive PN structure 202, thereby increasing the melting speed of the first conductive bonding layer 400 and improving the transfer efficiency of the light emitting device 200.

Fig. 14 is a schematic structural diagram of a conductive bonding layer according to an embodiment of the present invention, and as shown in fig. 14, optionally, the first conductive bonding layer 400 includes a eutectic layer 410 and a conductive metal layer 420 located between the eutectic layer 410 and the first driving electrode 110; the material of the conductive metal layer 420 includes metal balls or nano-silver material.

Referring to fig. 14, in the embodiment of the present invention, the first conductive bonding layer 400 may be a layered structure including a eutectic layer 410 and a conductive metal layer 420, when a current flowing through the eutectic layer 410 reaches a certain level, the eutectic layer 410 is heated and melted, so as to bond the light emitting device 200 and the first driving electrode 110, and the conductive metal layer 420 is used to realize conductivity of the first conductive bonding layer 400 and transmit an electrical signal. The materials of the eutectic layer 410 and the conductive metal layer 420 are not limited, and the eutectic layer 410 needs to satisfy the condition of being heated and melted, and the conductive metal layer 420 needs to have good conductivity to electrically connect the first driving electrode 110 and the light emitting device 200. Illustratively, the eutectic layer 410 may be a pure tin plating or a gold tin plating.

Optionally, the first power line 120 provides a first electrical signal to the anode of the photosensitive device 300, and the potential of the first electrical signal is less than 0V.

The light sensitive device 300 is turned on when a forward bias voltage is applied and is turned off when a reverse bias voltage is applied. Since the photosensor 300 is used only during the bonding process, the photosensor 300 can be turned off by providing the positive electrode of the photosensor 300 with the first electric signal having a potential less than 0V, preventing the switching on of the photosensor from affecting the normal display in the absence of the photosensor control switch, thereby achieving the state control of the photosensor 300.

Optionally, the display panel includes a detection stage and a display stage; in the detection phase, the first driving circuit 100 is configured to transmit a detection signal to the first driving electrode 110; in the display phase, the first driving circuit 100 is used for transmitting display signals to the first driving electrode 110.

Since the light emitting device 200 and the light sensing device 300 share one driving circuit, i.e., the first driving circuit 100, in order to avoid mutual interference of signals, it may be realized that the first driving circuit 100 transmits a detection signal to the first driving electrode 110 in a detection stage and the first driving circuit 100 transmits a display signal to the first driving electrode 110 in a display stage by adopting a time-sharing driving manner.

Based on the same inventive concept, the embodiments of the present invention further provide a transfer method of a light emitting device, where the transfer method is used to form the display panel of any embodiment of the present invention, and exemplary, fig. 15 is a flowchart of a transfer method of a light emitting device provided by the embodiment of the present invention, and as shown in fig. 15, the transfer method includes:

S110, providing an array substrate, a plurality of light emitting devices and a transfer head, wherein a first driving circuit and a photosensitive device are formed on one side of the array substrate facing the transfer head, and the first driving circuit comprises a first driving electrode and a first power line.

The specific structure of the light emitting device is not limited in this embodiment, and the light emitting device may be a vertical electrode structure or a same-side electrode structure. The following describes a light emitting device of a vertical structure as an example, but the embodiment of the present invention is not limited thereto.

Specifically, fig. 16 is a schematic structural diagram of an array substrate and a light emitting device before bonding according to an embodiment of the present invention, as shown in fig. 16, a first driving circuit (not shown) and a photosensitive device 300 are formed in the array substrate, where the first driving circuit includes a first driving electrode 110 and a first power line (not shown). The first driving circuit transmits a signal to the light emitting device 200 through the first driving electrode 110, driving the normal light emitting device 200 to emit light. The photosensitive device 300 is electrically connected between a first power line, which supplies a first electrical signal to the photosensitive device 300, and the first driving electrode 110. The transfer head 700 is used for transfer and transportation of the light emitting device 200. In the bonding process, it is necessary to energize both electrodes of the light emitting device 200, and thus, as shown in fig. 16, a second driving electrode 610 may be disposed on a surface of the transfer head 700 facing the array substrate, for electrically connecting with the light emitting device 200 of the vertical structure, to transmit signals to the light emitting device 200.

S120, a plurality of light emitting devices are picked up by adopting a transfer head, a first conductive bonding layer is arranged on one side of the first driving electrode, which faces away from the array substrate, and/or a first conductive bonding layer is arranged on one side of the light emitting device, which faces towards the first driving electrode.

The structure and the position of the first conductive bonding layer 400 are not limited in the embodiment of the present invention, and the first conductive bonding layer 400 may have a single-layer structure, a double-layer structure, or be disposed on the first driving electrode 110 or on the surface of the light emitting device 200. Specifically, referring to fig. 16, the first conductive bonding layer 400 in this embodiment has a double-layer structure, that is, the first conductive bonding layer 400 is disposed on the surfaces of the first driving electrode 110 and the light emitting device 200, so as to improve the bonding effect. In other embodiments, the first conductive bonding layer may be disposed only on the surface of the first driving electrode or the light emitting device, as long as the first driving electrode is in electrical contact with the light emitting device through the first conductive bonding layer.

And S130, contacting the picked-up light emitting devices with the first driving electrode through the first conductive bonding layer.

Fig. 17 is a schematic diagram of bonding a first driving electrode to a light emitting device according to an embodiment of the present invention, and as shown in fig. 17, a transfer head 700 positions the light emitting device 200 to the first driving electrode 110, so that the light emitting device 200 contacts the first driving electrode 110 through a first conductive bonding layer 400.

And S140, transmitting signals to the first driving electrode by adopting the array substrate, so that the light emitting device emits light.

With continued reference to fig. 17, in the bonding process, the array substrate and the transfer head 700 are simultaneously energized, and a specific first driving circuit transmits a signal to the light emitting device 200 through the first driving electrode 110, and the transfer head 700 transmits a signal to the light emitting device 200 through the second driving electrode 610, so that the current flowing through the first driving electrode 110 and the second driving electrode 610 can control the light emitting device 200 to emit light. Illustratively, the light emitting device 200 is normal on the left side and the light emitting device 200 is abnormal on the right side in fig. 17, and the light emitting device 200 is normal on the left side and the light emitting device 200 is not abnormal on the right side by the signal driving of the first driving electrode 110 and the second driving electrode 610.

And S150, if the light emitting device emits light, the photosensitive device receives the light emitted by the light emitting device and is started, a first electric signal provided by the first power line is applied to the first driving electrode through the photosensitive device, so that the first conductive bonding layer heats and melts, and the first driving electrode is bonded with the light emitting device.

Fig. 18 is a schematic bonding diagram of a normal light emitting device and an abnormal light emitting device according to an embodiment of the present invention, as shown in fig. 18, light emitted from a normal light emitting device 200 on the left side irradiates a photosensitive device 300 disposed corresponding to the normal light emitting device, the photosensitive device 300 is turned on, a first power line electrically connected to the photosensitive device 300 superimposes a first electric signal on a first driving electrode 110 through the photosensitive device 300, and increases current flowing through a first conductive bonding layer 400 electrically contacted with the first driving electrode 110, so that the first conductive bonding layer 400 heats and melts, and bonding between the normal light emitting device 200 on the left side and the first driving electrode 200 is achieved. And the right abnormal light-emitting device does not emit light, the photosensitive device is turned off, the current flowing through the first conductive bonding layer cannot heat and melt the first conductive bonding layer, and the right abnormal light-emitting device cannot be bonded with the first driving electrode.

Fig. 19 is a flowchart of another method for transferring a light emitting device according to an embodiment of the present invention, as shown in fig. 19, optionally, after S140, transmitting a signal to a first driving electrode by using an array substrate, the method further includes:

and S141, if the light emitting device does not emit light, the photosensitive device is kept off, and the first driving electrode is not bonded with the light emitting device.

Referring to fig. 18, the light emitting device 200 having an abnormality on the right side in fig. 18 receives no light because the light emitting device 200 having an abnormality does not emit light, and thus the photosensor 300 provided corresponding to the light emitting device 200 having an abnormality maintains an off state, and current flowing through the first conductive bonding layer 400 can be used only for light emitting device 200 and cannot cause the first conductive bonding layer 400 to heat and melt, the first conductive bonding layer 400 maintains an original state, and the light emitting device 200 having an abnormality is not bonded to its corresponding first driving electrode 110, thereby realizing that the light emitting device 200 having an abnormality is recognized while bonding, and simplifying the subsequent transfer and repair processes.

Optionally, the method further comprises: s160, transferring the transfer head, wherein the transfer head takes away the unbound light-emitting devices during transfer.

Fig. 20 is a schematic diagram of movement of the transfer head after bonding, and as shown in fig. 20, when the light emitting device 200 on the left side in fig. 20 is bonded to the first driving electrode 110, the light emitting device 200 on the left side cannot be transferred when the transfer head 700 is transferred. In fig. 20, when the light emitting device 200 on the right side is not bonded to the first driving electrode 110, the right light emitting device 200 is carried away by the transfer head 700 when the transfer head 700 transfers, and the subsequent transfer head 700 can provide a light emitting device for the pixel again to repair the position of the abnormal light emitting device 200.

In summary, in the transfer method of the light emitting device provided by the embodiment of the invention, the first driving circuit is utilized to transmit the signal through the first driving electrode to enable the light emitting device to emit light, and the photosensitive device is started when receiving the light emitted by the normal light emitting device, so that the first electric signal provided by the first power line electrically connected with the photosensitive device is superimposed to the first driving electrode, the current flowing through the first conductive bonding layer in contact with the first driving electrode is increased, the first conductive bonding layer is heated and melted, and then the bonding between the normal light emitting device and the first driving electrode is completed, and the abnormal light emitting device cannot be bonded, so that the abnormal light emitting device is detected while the bonding process between the normal light emitting device and the first driving electrode is carried out, and the detection process after bonding is not required to be separately set; only one light emitting device is needed to be configured for each pixel, so that the PPI is improved and the cost is reduced; the state of the photosensitive device is recoverable after illumination, so that the photosensitive device has stable performance and can be recycled, and the subsequent transferring and repairing processes can be simplified.

It should be noted that, in the present specification, each embodiment is described in a progressive manner, and each embodiment is mainly described as different from other embodiments, and identical and similar parts between the embodiments are all enough to be referred to each other.

Note that the above is only a preferred embodiment of the present invention and the technical principle applied. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, and that various obvious changes, rearrangements, combinations, and substitutions can be made by those skilled in the art without departing from the scope of the invention. Therefore, while the invention has been described in connection with the above embodiments, the invention is not limited to the embodiments, but may be embodied in many other equivalent forms without departing from the spirit or scope of the invention, which is set forth in the following claims.

Claims

1. A display panel, comprising: a first driving circuit, a light emitting device, and a light sensing device;

the first driving circuit further comprises a first power line, a first end of the photosensitive device is electrically connected to the first power line, a second end of the photosensitive device is electrically connected to the first driving electrode, the photosensitive device is used for being started when light emitted by the light emitting device is received, a first electric signal provided by the first power line is superposed on the first driving electrode, and then the first conductive bonding layer is heated to bond the first driving electrode and the light emitting device;

The first driving circuit further comprises a second driving electrode, the first driving electrode is in electrical contact with the light-emitting device through the first conductive bonding layer, and the second driving electrode is in electrical contact with the light-emitting device through the second conductive bonding layer;

the first driving circuit is used for transmitting signals to the first driving electrode and the second driving electrode so that the normal light-emitting device emits light;

the light emitting device comprises a first electrode and a second electrode and a light emitting layer positioned between the first electrode and the second electrode, wherein the first electrode and the second electrode of the light emitting device are positioned on the same side of the light emitting layer;

the first driving electrode is in electrical contact with the first electrode through the first conductive bonding layer, and the second driving electrode is in electrical contact with the second electrode through the second conductive bonding layer;

the display panel comprises a first substrate and an array layer positioned at one side of the first substrate;

the first driving circuit and the photosensitive device are positioned on the array layer, and the light emitting device is positioned on one side of the array layer, which is away from the first substrate;

the first driving electrode, the second driving electrode, the first electrode and the second electrode are transparent electrodes;

The display panel further comprises a second driving circuit, wherein the second driving circuit comprises a second driving electrode, and the second driving electrode is in electrical contact with the light emitting device;

the first driving circuit transmits signals to the first driving electrode, and the second driving circuit transmits signals to the second driving electrode, so that the normal light emitting device emits light.

2. The display panel of claim 1, wherein the light emitting device is a micro light emitting diode; the light emitting layer comprises a first type semiconductor layer, an active layer and a second type semiconductor layer which are sequentially stacked;

the first electrode is located on one side of the first type semiconductor layer facing the active layer, and the second electrode is located on one side of the second type semiconductor layer facing away from the active layer.

3. The display panel of claim 1, wherein the light emitting device comprises a first electrode and a second electrode and a light emitting layer between the first electrode and the second electrode, the first electrode and the second electrode of the light emitting device being located on opposite sides of the light emitting layer;

the first driving electrode is electrically contacted with the first electrode through the first conductive bonding layer, and the second driving electrode is electrically contacted with the second electrode.

4. A display panel according to claim 3, wherein the light emitting device is a micro light emitting diode; the light emitting layer comprises a first type semiconductor layer, an active layer and a second type semiconductor layer which are sequentially stacked;

the first electrode is positioned on one side of the first type semiconductor layer, which is away from the active layer, and the second electrode is positioned on one side of the second type semiconductor layer, which is away from the active layer.

5. A display panel according to claim 3, wherein the display panel comprises opposing first and second substrates;

the first driving circuit and the photosensitive device are positioned on one side of the first substrate facing the second substrate, the second driving circuit is positioned on one side of the second substrate facing the first substrate, and the light emitting device is positioned between the first substrate and the second substrate;

the first driving electrode and the first electrode are transparent electrodes, and the second driving electrode and the second electrode are reflecting electrodes.

6. The display panel of claim 1, wherein a first end of the photosensitive device is electrically connected to the first power line through a first photosensitive switch;

The first driving circuit further comprises a first gate line, wherein the first gate line is electrically connected with the control end of the first photosensitive switch and is used for controlling the first photosensitive switch to be turned on or turned off;

the working process of the display panel comprises a bonding stage, wherein in the bonding stage, the first photosensitive switch is turned on, and in the non-bonding stage, the first photosensitive switch is turned off.

7. The display panel of claim 1, wherein the second end of the photosensitive device is electrically connected to the first driving electrode through a second photosensitive switch;

the first driving circuit further comprises a second gate line, wherein the second gate line is electrically connected with the control end of the second photosensitive switch and is used for controlling the second photosensitive switch to be turned on or off;

the working process of the display panel comprises a bonding stage, wherein the second photosensitive switch is turned on in the bonding stage, and the second photosensitive switch is turned off in the non-bonding stage.

8. The display panel of claim 1, wherein the first driving circuit comprises a pixel circuit comprising a driving module and a light emission control module;

the driving module is used for providing driving current for the light emitting device;

The light-emitting control module is connected in series between the driving module and the light-emitting device, the light-emitting control module comprises a first driving electrode, and the light-emitting control module is used for controlling whether the driving current flows through the first driving electrode and the light-emitting device.

9. The display panel of claim 8, wherein the second end of the photosensor is electrically connected to the first driving electrode through the driving module.

10. The display panel of claim 9, wherein the drive module comprises a drive transistor comprising a gate, a first terminal, and a second terminal;

the second terminal of the photosensitive device is electrically connected to the gate of the driving transistor, or the second terminal of the photosensitive device is electrically connected to the first terminal of the driving transistor, or the second terminal of the photosensitive device is electrically connected to the second terminal of the driving transistor.

11. The display panel of claim 8, wherein the second end of the photosensor is electrically connected to the first driving electrode through the light emission control module.

12. The display panel of claim 11, wherein the light emission control module comprises a first light emission control transistor connected in series between the driving module and the first driving electrode, the first light emission control transistor comprising a gate electrode, a first terminal, and a second terminal;

The second end of the photosensitive device is electrically connected to the gate electrode of the first light emitting control transistor, or the second end of the photosensitive device is electrically connected to the first end of the first light emitting control transistor, or the second end of the photosensitive device is electrically connected to the second end of the first light emitting control transistor.

13. The display panel according to claim 8, wherein the pixel circuit is electrically connected to a reference voltage line for supplying a reference voltage signal to the pixel circuit;

the reference voltage line is multiplexed to the first power supply line.

14. The display panel according to claim 8, wherein the pixel circuit is electrically connected to a low-level signal line for supplying a low-level signal to the pixel circuit;

the low-level signal line is multiplexed as the first power supply line.

15. The display panel of claim 8, wherein the display panel comprises:

a substrate base;

the array layer is positioned at one side of the substrate and comprises a pixel circuit structure layer and a photosensitive device structure layer, the pixel circuit structure layer comprises an active layer, a gate insulation layer, a gate metal layer, an interlayer insulation layer and a source drain metal layer, and the photosensitive device structure layer comprises a photosensitive PN junction and a positive electrode layer and a negative electrode layer;

And the driving electrode layer is positioned on one side of the array layer, which is away from the substrate, and comprises at least one first driving electrode.

16. The display panel of claim 15, wherein the positive and negative electrode layers of the photosensitive device structure layer are co-layer with the gate metal layer of the pixel circuit structure layer; or alternatively, the process may be performed,

the positive electrode layer and the negative electrode layer of the photosensitive device structure layer are the same layer as the source electrode and drain electrode metal layer of the pixel circuit structure layer; or alternatively, the process may be performed,

and the positive electrode layer and the negative electrode layer of the photosensitive device structure layer are the same layer as the driving electrode layer.

17. The display panel of claim 15, wherein the photosensitive PN junction of the photosensitive device structure layer is co-layer with the active layer of the pixel circuit structure layer.

18. The display panel of claim 15, wherein the film layer on the side of the photosensitive PN junction facing away from the substrate is a transparent film layer;

in a direction perpendicular to the substrate base plate, the orthographic projection of the photosensitive PN structure at least partially overlaps with the orthographic projection of the light emitting device.

19. The display panel of claim 1, wherein the first conductive bonding layer comprises a eutectic layer and a conductive metal layer between the eutectic layer and the first drive electrode;

The material of the conductive metal layer comprises metal balls or nano silver material.

20. The display panel of claim 19, wherein the eutectic layer is a pure tin plating or a gold tin plating.

21. The display panel according to claim 1, wherein the first power line supplies a first electric signal to the positive electrode of the photosensor, and wherein a potential of the first electric signal is less than 0V.

22. The display panel of claim 1, wherein the display panel comprises a detection phase and a display phase;

in the detection stage, the first driving circuit is used for transmitting a detection signal to the first driving electrode;

in the display stage, the first driving circuit is used for transmitting display signals to the first driving electrode.

23. A transfer method of a light emitting device for forming the display panel according to any one of claims 1 to 22, the transfer method comprising:

24. The transfer method of claim 23, further comprising, after transmitting a signal to the first driving electrode using the array substrate:

if the light emitting device does not emit light, the photosensitive device remains off, and the first driving electrode is not bonded to the light emitting device.

25. The transfer method of claim 24, further comprising: and transferring the transfer head, wherein the transfer head brings away the unbound light-emitting devices during transfer.