CN115915820A - Light-emitting substrate, preparation method thereof and display device - Google Patents

Abstract

The present disclosure provides a light emitting substrate, a method for manufacturing the same, and a display device, the light emitting substrate including: driving the back plate; the first pixel defining layer is arranged on the driving backboard and provided with a plurality of opening areas; and a light emitting device disposed at the opening region. The light emitting device includes: the light-emitting diode comprises a first electrode, a light-emitting functional layer and a semiconductor film layer arranged between the first electrode and the light-emitting functional layer. The first electrode at least covers the bottom surface and the side wall of the opening area, the material of the semiconductor film layer has a conductive state and a non-conductive state, the semiconductor film layer comprises a first functional unit in the non-conductive state, and the first functional unit covers the first electrode arranged on the side wall of the opening area.

Description

Light-emitting substrate, preparation method thereof and display device

Technical Field

The embodiment of the disclosure relates to the technical field of display, in particular to a light-emitting substrate, a preparation method thereof and a display device.

Background

Since the OLED (Organic Light-Emitting Diode) is Light, thin, self-luminous, and fast in response speed, it has wide applications in near-eye display fields such as AR (enhanced display), VR (Virtual display), and the like. With the increasing demand of people for display, the market demands OLED products with high brightness, and therefore, improving the brightness of OLED products is especially important for the development of OLEDs.

Disclosure of Invention

The embodiment of the disclosure provides a light-emitting substrate, a preparation method thereof and a display device.

In a first aspect, an embodiment of the present disclosure provides a light emitting substrate, including:

driving the back plate;

a first pixel defining layer disposed on the driving backplane, the first pixel defining layer having a plurality of opening regions; and

a light emitting device disposed at the opening region, the light emitting device including: the light-emitting diode comprises a first electrode, a light-emitting functional layer and a semiconductor film layer arranged between the first electrode and the light-emitting functional layer;

the first electrode at least covers the bottom surface and the side wall of the opening area, the material of the semiconductor film layer has a conductive state and a non-conductive state, the semiconductor film layer comprises a first functional unit in the non-conductive state, and the first functional unit covers the first electrode arranged on the side wall of the opening area.

Further, the semiconductor film layer further comprises a second functional unit in the conductive state, and the second functional unit covers the first electrode arranged on the bottom surface of the opening region.

Further, the semiconductor film layer is a graphene film, the first functional unit is a graphene film in an intrinsic state, and the second functional unit is a graphene film subjected to non-conductor processing.

Furthermore, the thickness of the semiconductor film layer is 10-2000 angstroms.

Further, the first electrode extends from the open region to the top of the first pixel defining layer, and the first functional unit also covers a first electrode disposed at a target corner, the target corner including a corner between the open region sidewall and the top of the first pixel defining layer.

Further, the light-emitting substrate further includes: a second pixel defining layer;

the second pixel defining layer is stacked on top of the first pixel defining layer and is positioned adjacent to a spaced region of the first electrode of the light emitting device.

Further, the light emitting function layer includes: a hole injection layer and a hole transport layer;

the thickness of the second pixel defining layer is at least greater than the sum of the thicknesses of the first electrode, the semiconductor film layer, the hole injection layer and the hole transport layer in a direction perpendicular to the driving backplane to block the hole injection layer and the hole transport layer of adjacent light emitting devices.

Further, the light emitting function layer further includes: a light-emitting layer and a second electrode;

the thickness of the second pixel defining layer is larger than the sum of the thicknesses of the first electrode, the semiconductor film layer and the light-emitting function layer along the direction perpendicular to the driving back plate so as to block the light-emitting function layers of the adjacent light-emitting devices.

Further, the material of the second pixel defining layer is an inorganic insulating material.

In a second aspect, embodiments of the present disclosure provide a method for preparing a light emitting substrate, the method including:

forming a first pixel defining layer on a driving backplane, the first pixel defining layer having a plurality of opening regions;

forming a first electrode in an opening region of the first pixel defining layer, the first electrode covering at least a bottom surface and a sidewall of the opening region;

forming a semiconductor film layer on the first electrode, wherein the material of the semiconductor film layer has a conductive state and a non-conductive state, the semiconductor film layer comprises a first functional unit in the non-conductive state, and the first functional unit covers the first electrode arranged at the side wall of the opening region;

and forming a light-emitting functional layer.

Further, forming a semiconductor film layer on the first electrode, including:

forming a graphene film on the surface of the driving backboard on which the first electrode is formed;

and carrying out non-conductor treatment on the graphene film in the target area to form the first functional unit.

Further, the non-conductor processing is performed on the graphene film of the target area, and the processing includes:

and carrying out surface treatment on the graphene film of the target area by using argon and/or hydrogen to generate hydrogenated graphene in the target area.

Further, after forming a semiconductor film layer on the first electrode and before forming a light emitting function layer, the method further includes:

forming a second pixel defining layer on top of the first pixel defining layer, the second pixel defining layer being located at a spaced region of the first electrodes of the adjacent light emitting devices.

In a third aspect, embodiments of the present disclosure provide a display device, including the light-emitting substrate described in the first aspect.

The technical scheme provided by the embodiment of the disclosure at least has the following technical effects or advantages:

according to the light-emitting substrate provided by the embodiment of the disclosure, on the basis that the first electrode is additionally arranged on the side wall of the opening of the first pixel defining layer to improve the brightness of the light-emitting device, the semiconductor film layer is additionally arranged, the material of the semiconductor film layer has a conductive state and a non-conductive state, the semiconductor film layer comprises the first functional unit in the non-conductive state, and the first functional unit covers the first electrode arranged on the side wall of the opening region and serves as the protective layer on the side wall. The first functional unit has better insulating property, so that the problem that the luminous functional layer material at the side wall of the opening is thinner to cause cavity length change and influence the light emission of the light-emitting device can be effectively solved, and the problem that the thin luminous functional layer material at the side wall of the opening area is easy to cause short circuit is solved. In addition, the thickness of the semiconductor film layer is thinner than that of the resin material, so that the limitation of the introduction of the protective layer on the area of the light emitting region of the first electrode can be reduced, and the improvement of the light emitting brightness of the light emitting device is facilitated.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the application. Also, like reference numerals are used to refer to like parts throughout the drawings. In the drawings:

fig. 1 is a first schematic structural diagram of an exemplary light-emitting substrate in an embodiment of the present disclosure;

FIG. 2 is a second schematic diagram illustrating an exemplary light-emitting substrate according to an embodiment of the present disclosure;

fig. 3 is a schematic structural diagram of an exemplary light-emitting substrate in an embodiment of the present disclosure;

fig. 4 is a flowchart of a method for manufacturing a light-emitting substrate according to an embodiment of the disclosure;

FIG. 5 is a process diagram illustrating the deposition of a resin material layer in an embodiment of the present disclosure;

FIG. 6 is a process diagram illustrating the patterning of a resin material layer according to an embodiment of the present disclosure;

FIG. 7 is a process diagram of electrode film deposition in accordance with an embodiment of the present disclosure;

FIG. 8 is a process diagram illustrating patterning of an electrode film layer according to an embodiment of the present disclosure;

fig. 9 is a process diagram of forming a graphene thin film in an embodiment of the present disclosure;

fig. 10 is a process diagram of a graphene film after a nonconductor process in an embodiment of the present disclosure;

fig. 11 is a first processing diagram of the second pixel defining layer and the light emitting function layer according to the embodiment of the disclosure;

fig. 12 is a second processing diagram of the second pixel defining layer and the light emitting functional layer in the embodiment of the disclosure.

Detailed Description

There are various ways to improve the brightness of the OLED device, for example, the following methods can be adopted: 1. the brightness of an EL (Electro-Luminescence) device is improved; 2. the transmittance of a TFE (Thin Film Encapsulation) layer is improved; 3. a Color Filter is formed on the packaging layer by adopting WOLED + COE (Color Filter on Encapsulation), so that the transmittance of the Color film is improved; 4. other device structures are improved by adopting Micro-Lens and the like.

In some examples, a dual Layer PDL (Pixel Definition Layer) is employed to increase OLED device brightness. As shown in fig. 1, the luminance of the OLED device is improved by adding a reflective Anode electrode to the sidewall of the opening of the first pixel defining layer PDL 1. The method has simple process. However, the side edge of the EL coating process is made of a thin material, which causes a change in cavity length and affects the light emission of the OLED, and the thin material at the side edge and the sharp corner easily causes a short circuit (short) problem due to direct contact between the anode and the cathode. Therefore, the second pixel defining layer PDL2 needs to be formed with holes in the first pixel defining layer PDL1 to cover the side anodes, and the pixel defining layer is usually made of a resin material, and due to the influence of factors such as low resolution of the resin material and misalignment (Overlay) in the manufacturing process, the thickness of the second pixel defining layer PDL2 covering the side anodes is thick, so that the light emitting area of the Anode is limited.

In view of this, the embodiments of the present disclosure provide a technical solution, in which a semiconductor material having two states of a conductive state and a non-conductive state is used, and a first functional unit in the non-conductive state is provided as a protective layer to cover a first electrode disposed at a sidewall of an opening of a first pixel defining layer, so as to effectively improve the problem that an EL material at the sidewall is thinner, which causes a change in cavity length, and affects light emission of an OLED, and improve the problem that a material thinner at an EL side edge easily causes a direct contact between the first electrode and a second electrode of the OLED, which causes short. Moreover, the semiconductor material is relatively thin, occupies a small space, and can reduce the limitation of the introduction of the protective layer on the area of the light emitting area of the first electrode, thereby being beneficial to improving the light emitting brightness of the OLED.

Exemplary embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. It is noted that in the drawings, the sizes of layers and regions may be exaggerated for clarity of illustration. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

In a first aspect, as shown in fig. 2, an embodiment of the present disclosure provides a light emitting substrate 10, including: a driving backplane 100, a first pixel defining layer 110, and a light emitting device.

The driving back plate 100 includes a substrate and a pixel driving circuit disposed on the substrate, and the pixel driving circuit is connected to the corresponding light emitting device for driving the light emitting device to emit light.

The material selection of the substrate base plate is determined according to the requirements of practical application scenarios. For example, when the method is applied to a display device with a higher pixel density, such as a micro-OLED display device, since the size of a single pixel is smaller and the process precision requirement is higher, a silicon-based drive can be adopted, that is, the substrate base plate is a silicon substrate. Of course, in order to match the panel factory process and reduce the cost, a glass-based drive may be adopted, that is, the substrate base plate is a glass substrate. At this time, the glass-based OLED pixel driver may be manufactured in a glass-based panel factory, and then cut into silicon wafer wafers (wafers) to the silicon-based OLED micro-display factory to perform subsequent preparation of the first electrode 120, the semiconductor film layer 130, the light emitting functional layer 140, and the like. The display device with higher pixel density adopts the integration of the glass-based device process and the silicon-based device process, so that not only can lower cost be maintained, but also a more complex pixel circuit (needing to occupy larger Layout space) can be maintained.

Taking a glass-based LTPS (Low Temperature Poly-Silicon) drive as an example, the driving backplane 100 may have a hierarchical structure including: the liquid crystal display device comprises a glass substrate, a Buffer layer (Buffer), an active layer (P-Si), a first grid electrode insulating layer (GI 1), a first grid electrode metal layer (Gate 1), a second grid electrode insulating layer (GI 2), a second grid electrode metal layer (Gate 2), an interlayer dielectric layer (ILD), a DATA line metal layer (DATA), a first passivation layer (PVX 0), a first metal layer (MT 0), a second passivation layer (PVX 1), a second metal layer (MT 1), a third passivation layer (PVX 2), a third metal layer (MT 2), a fourth passivation layer (PVX 3) and a fourth metal layer (MT 3) which are sequentially stacked. It should be noted that, in order to facilitate the edge recognition of the glass-based wafer, a metal ring may be formed on the first Gate metal layer (Gate 1) for alignment.

The first pixel defining layer 110 is disposed on the driving back plate 100, and has a plurality of opening regions for defining effective light emitting regions of the respective light emitting devices. For example, the material of the first pixel defining layer 110 may be a resin material. It should be noted that when the manufacturing process is combined with a silicon-based device process, the first pixel defining layer 110 can also be manufactured during the manufacturing process of the glass-based pixel driver, for example, after the fourth metal layer (MT 3) is manufactured. Of course, the specific preparation process may be determined according to the needs of the actual application scenario, which is not limited in this embodiment.

The light emitting device is disposed at the opening region of the first pixel defining layer 110. The light emitting device includes: a first electrode 120, a light emitting function layer 140, and a semiconductor film layer 130 disposed between the first electrode 120 and the light emitting function layer 140. For example, for an OLED light emitting device, the light emitting function layer 140 may include a first functional material layer, a light emitting layer, a second functional material layer, and a second electrode. Wherein, the first functional material layer and the second functional material layer can be arranged according to actual needs. For example, the first functional material layer may include: a Hole Injection Layer (HIL) and a Hole Transport Layer (HTL); the second functional material layer may include: an Electron Transport Layer (ETL) and an Electron Injection Layer (EIL).

In some examples, the first electrode 120 is a reflective electrode, e.g., the first electrode 120 may be an anode and the second electrode may be a cathode. The first electrode 120 is made of an opaque electrode material having a reflective property, such as a metal material, and the second electrode may be made of a transparent electrode material, and light is emitted from the second electrode.

For example, an exemplary luminescent functional layer 140 may include, in order from bottom to top: a hole injection layer, a hole transport layer, an Electron Blocking Layer (EBL), a light emitting layer, a Hole Blocking Layer (HBL), an electron transport layer, an electron injection layer, a Cathode Patterned Layer (CPL), and a Cathode (CTD). The light emitting layer may include: a blue electroluminescent layer (BEML), a green electroluminescent layer (GEML), and a red electroluminescent layer (REML).

The opening region of the first pixel defining layer 110 includes an opening bottom surface and an opening sidewall. The first electrode 120 is disposed at least on the opening bottom surface and the opening sidewall.

In the embodiment of the present disclosure, the material of the semiconductor film 130 itself has a conductive state and a non-conductive state, and may be graphene, for example, or may be other suitable semiconductor materials. Taking graphene as an example, the graphene is a two-dimensional material, the characteristic of which is between that of a semiconductor and a conductor, when the graphene is in an eigenstate, due to energy band overlapping, the conductivity of the graphene has a metal characteristic, and the conductivity can reach 20000cm ² the/V.S can achieve the metal work function matched with EL luminescence and can be used as a transparent electrode. When the graphene is treated by argon or hydrogen or a mixed gas of the argon and the hydrogen, hydrogenated graphene can be generated and can be used as a transparent non-conductor material.

In some examples, the semiconductor film 130 includes a first functional unit 131 in a non-conductive state, and the first functional unit 131 covers the first electrode 120 disposed at the sidewall of the opening region. For example, the first functional unit 131 is disposed to be stacked with the first electrode 120 disposed at the opening sidewall, and an orthogonal projection of the first electrode 120 disposed at the opening sidewall on the substrate base is located within an orthogonal projection of the first functional unit 131 on the substrate base. In some examples, the orthographic projections of the two may be substantially coincident. "substantially" means that the difference is within an acceptable error range. In addition, the thickness of the semiconductor film layer 130 can be made thinner than that of the resin material. For example, the thickness of the semiconductor film 130 may be 10 to 2000 angstroms.

The first functional unit 131 has a good insulating property and a thin thickness, so that the problem that the EL material at the side wall is thin to cause a change in cavity length and affect the light emission of the light emitting device is effectively solved, the problem that the thin material at the side edge of the EL easily causes short due to the direct contact between the first electrode 120 and the second electrode is solved, the limitation of the introduction of the protective layer on the area of the light emitting area of the first electrode 120 is reduced, and the improvement of the light emission brightness of the light emitting device is facilitated.

In some examples, the first electrode 120 may also extend from the opening region to the top of the first pixel defining layer 110, and the first electrodes 120 of the adjacent light emitting devices are spaced apart at the top of the first pixel defining layer 110, for convenience of processing and further improvement of light emitting luminance. At this time, the first functional unit 131 may further cover the first electrode 120 disposed at a corner of the target, where the corner of the target includes a corner between a sidewall of the opening region and a top of the first pixel defining layer 110, so as to protect the corner, improve a short problem caused by direct contact between the first electrode 120 and the second electrode due to a thinner EL material at the corner, and further improve reliability of the light emitting device.

Further, the semiconductor film 130 may further include a second functional unit 132 in a conductive state, and the second functional unit 132 covers the first electrode 120 disposed on the bottom surface of the opening region. Since the second functional unit 132 is conductive, the charge transfer between the first electrode 120 and the light emitting functional layer 140 on the bottom surface of the opening region is not affected.

For example, taking the material of the semiconductor film layer 130 as graphene as an example, a graphene thin film may be formed on the surface of the driving backplate 100 where the first electrode 120 is prepared, then a photoresist is coated on the surface of the graphene thin film, and after exposure and development, a mask covering the bottom surface of the opening is formed to expose the graphene thin film in the other region except the bottom surface of the opening, and then argon or hydrogen or a mixed gas of the argon and hydrogen is introduced to perform nonconducting treatment on the graphene thin film not covered by the mask, so that the graphene thin film is in a nonconducting state, thereby forming the first functional unit 131. Thereafter, the mask may be removed, and the portion of the graphene thin film covered by the mask is still in an intrinsic state, i.e. in a conductive state, as the second functional unit 132.

Since the second functional unit 132 covered on the bottom surface of the opening is conductive, it is not necessary to open a hole in the material to expose the first electrode 120 on the bottom surface of the opening in terms of processing level, so that the area of the light emitting area of the first electrode 120 is not affected by the precision of the opening in the manufacturing process, which is beneficial to reducing the shielding of the first electrode 120 on the bottom surface of the opening caused by the introduction of the first functional unit 131, i.e. reducing the limitation on the area of the light emitting area of the first electrode 120, thereby improving the light emitting brightness of the light emitting device.

In some examples, to further assist in defining an effective light emitting area of each light emitting device, the light emitting substrate 10 provided by the embodiments of the present disclosure may further include: the second pixel defining layer 150. The second pixel defining layer 150 is stacked on top of the first pixel defining layer 110, and may be located at a spaced region of the first electrodes 120 of the adjacent light emitting devices, for example. The second pixel defining layer 150 also has a plurality of opening regions, and the opening regions of the second pixel defining layer 150 are disposed corresponding to the opening regions of the first pixel defining layer 110. The opening area size of the second pixel defining layer 150 is larger than the opening area size of the first pixel defining layer 110, that is, the orthographic projection of the opening area of the first pixel defining layer 110 on the driving backplate 100 is located within the orthographic projection of the opening area of the second pixel defining layer 150 on the driving backplate 100.

The thickness of the second pixel defining layer 150 in the direction perpendicular to the driving backplane 100 may be set according to the blocking requirement of the adjacent light emitting devices in the practical application scenario. For example, the thickness of the second pixel defining layer 150 may be at least greater than the sum of the thicknesses of the first electrode 120, the semiconductor film layer 130, the hole injection layer, and the hole transport layer positioned on top of the first pixel defining layer 110. The hole injection layer and the hole transport layer are generally formed in a single layer by an evaporation process, and in order to avoid communication between the hole injection layer and the hole transport layer of adjacent light emitting devices and use the driving backplane 100 as a height reference, the height of the top of the second pixel defining layer 150 may at least exceed the height of the hole transport layer to be formed, so as to block the hole injection layer and the hole transport layer of the adjacent light emitting devices and reduce lateral crosstalk.

It should be noted that the light emitting layer, the second functional material layer, and the second electrode of adjacent light emitting devices may or may not be shared, and are specifically configured according to the needs of the practical application scenario. For example, when the light emitting devices include a red light emitting device, a green light emitting device, and a blue light emitting device, the light emitting layers of the different light emitting devices need to be separated from each other. When the light emitting device includes only a white light emitting device, light emitting layers of different light emitting devices may be shared.

In some examples, the thickness of the second pixel defining layer 150 may be greater than the sum of the thicknesses of the first electrode 120, the semiconductor film layer 130, and the light emitting function layer 140 positioned on top of the first pixel defining layer 110 in a direction perpendicular to the driving backplane 100 to block the light emitting function layer 140 of the adjacent light emitting device. At this time, the light emitting function layers 140 of the adjacent light emitting devices may be separated by the second pixel defining layer 150, which is advantageous to further reduce the lateral crosstalk.

For example, the cross-sectional shape of the second pixel defining layer 150 may be approximately rectangular, as shown in fig. 2, or may be trapezoidal, as shown in fig. 3, depending on the materials used, which is not limited in this embodiment.

In some examples, the material of the second pixel defining layer 150 may be an inorganic insulating material such as silicon nitride or silicon oxide. The inorganic material can adopt dry etching such as plasma etching process and the like, can achieve higher etching precision, and the slope angle can reach more than 80 degrees and approach 90 degrees, so that the section shape of the inorganic material is similar to a rectangle. The slope angle is an angle formed between the sidewall of the second pixel defining layer 150 and the plane of the top of the first pixel defining layer 110.

The higher the etching precision is, the closer the gradient angle is to 90 degrees, so that on one hand, the smaller the space occupied by the second pixel defining layer 150 on the top of the first pixel defining layer 110 is, the larger the area of the light-emitting function layer 140 of each light-emitting device is, and the improvement of the light-emitting brightness is facilitated; on the other hand, the second pixel defining layer 150 can have a better blocking effect on the hole injection layer and the hole transport layer of the adjacent light emitting devices in the process of evaporating the light emitting function layer 140.

Of course, in other examples, the second pixel defining layer 150 may also be made of an organic material, such as a resin material, which is not limited in this embodiment.

In addition, the light emitting substrate 10 provided by the embodiment of the present disclosure may further include: and an encapsulation layer 160. The stacked arrangement of encapsulation layer 160 is in one side of emitting device that keeps away from drive backplate 100, not only can keep apart emitting device and external world, has avoided water and oxygen to invade emitting device, influences emitting substrate 10's life, also can realize the planarization effect simultaneously, makes things convenient for other devices to make on flat surface. For example, a color film layer may be further disposed on the encapsulation layer 160, or a lens array with a dimming effect may be disposed, which may be specifically set according to actual needs.

For example, the encapsulation layer 160 may include at least three layers, which are set according to actual requirements. In some examples, the encapsulation layer 160 may include a first inorganic film layer, an organic film layer, and a second inorganic film layer stacked in a stacked manner, wherein the inorganic film layer plays a role of blocking water and oxygen, and the second inorganic film layer covers the organic film layer to prevent the organic film layer from being exposed, and the organic film layer plays a role of planarization to cover defects and particles generated during the encapsulation process to relieve the stress of the inorganic film layer.

In a second aspect, an embodiment of the present disclosure further provides a method for preparing a luminescent substrate, which is used to prepare the luminescent substrate 10 provided in the first aspect. As shown in fig. 4, the method includes at least

In step S401, a first pixel defining layer is formed on the driving backplane, and the first pixel defining layer has a plurality of opening regions.

For example, as shown in fig. 5, a resin material layer 111 with a certain thickness may be deposited on the surface of the driving backplate 100, and then the resin material layer 111 is patterned through photolithography and etching processes to obtain the first pixel defining layer 110, as shown in fig. 6. The specific preparation process can refer to the related art, and is not described herein again. The open region of the first pixel defining layer 110 serves to define an effective light emitting region of each light emitting device. Next, light emitting devices may be formed on the driving back plate 100 through the following steps S402 to S404.

In step S402, a first electrode is formed in the opening region of the first pixel defining layer 110, and the first electrode at least covers the bottom surface and the sidewall of the opening region.

For example, the first electrode 120 may serve as a reflective anode of the light emitting device. In order to improve the hole injection efficiency, it is required that the work function of the anode be as high as possible. The reflective anode is opaque and has reflective properties. For example, a multi-layer structure of ITO (indium tin oxide)/Ag (silver)/ITO may be employed, in which Ag as an intermediate layer has a reflective property.

The first electrode 120 covers the sidewall of the opening region in addition to the bottom surface of the opening region, which is advantageous for improving the luminance of the light emitting device. In some examples, the first electrode 120 may also extend from the opening region to the top of the first pixel defining layer 110, and the first electrodes 120 of the adjacent light emitting devices are spaced apart at the top of the first pixel defining layer 110, for convenience of processing and further improvement of light emitting luminance.

For example, taking a multi-film structure of ITO/Ag/ITO as an example, an ITO film may be deposited on the surface of the structure shown in fig. 6, and then an Ag film may be deposited, and an ITO film may be deposited, so as to obtain the electrode film layer 121 shown in fig. 7. Further, the electrode film layer 121 in fig. 7 is subjected to a patterning process to form the first electrode 120, as shown in fig. 8.

Step S403, forming a semiconductor film layer on the first electrode, where the material of the semiconductor film layer has a conductive state and a non-conductive state, the semiconductor film layer includes a first functional unit in the non-conductive state, and the first functional unit covers the first electrode disposed on the sidewall of the opening region.

In some examples, the above process of forming the semiconductor film layer 130 on the first electrode 120 may include: as shown in fig. 9, a graphene film 133 is formed on the surface of the driving backplate 100 on which the first electrode 120 is formed; the graphene thin film 133 in the target region is subjected to nonconduction processing to form the first functional unit 131, as shown in fig. 10. For example, the target area may include: the sidewall of the opening region and the top of the first pixel defining layer 110 are covered with the region of the first electrode 120.

For example, the non-conductor processing of the graphene thin film of the target area includes: and carrying out surface treatment on the graphene film of the target area by using argon and/or hydrogen to generate hydrogenated graphene in the target area.

For example, a photoresist may be coated on the surface of the graphene film 133, and after exposure and development, a mask covering the bottom surface of the opening may be formed to expose the graphene film in the target region, and then argon or hydrogen or a mixture of the two gases may be introduced to perform a non-conductive treatment on the graphene film in the target region so that the graphene film is in a non-conductive state, thereby forming the first functional unit 131. After that, the mask is removed again, and the part of the graphene film covered by the mask is still in an intrinsic state, i.e. in a conductible state.

In consideration of simplifying the manufacturing process and saving the cost as much as possible, the graphene film in the conductive state on the bottom surface of the opening can be retained. At this time, the semiconductor film 130 includes a second functional unit 132 in addition to the first functional unit 131, for specific reference, the related description of the first aspect is not repeated herein. Of course, in other examples, the graphene film in a conductive state on the bottom surface of the opening may be removed as needed, which is not limited in this embodiment.

In some examples, after forming the semiconductor film 130 on the first electrode 120 and before performing the following step S304, the preparation method may further include: a second pixel defining layer 150 is formed on top of the first pixel defining layer 110, and the second pixel defining layer 150 is positioned at a spaced region of the first electrodes 120 of the adjacent light emitting devices.

For example, when the second pixel defining layer 150 is made of an organic material such as a resin material, the second pixel defining layer 150 may be formed by depositing an organic material layer with a certain thickness on the surface of the driving backplate 100 on which the semiconductor film layer 130 is formed, and then patterning the resin layer, as shown in fig. 11.

For another example, when the second pixel defining layer 150 is made of an inorganic insulating material, such as silicon oxide or silicon nitride, the inorganic insulating material layer with a certain thickness may be deposited on the surface of the driving back plate 100 on which the semiconductor film 130 is formed, and then the inorganic insulating material layer may be patterned by using a dry etching process to form the second pixel defining layer 150, as shown in fig. 12.

In step S404, a light emitting function layer is formed.

For example, the light emitting function layer 140 may include: the light emitting function layer 140 may include a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer, and a second electrode. In a specific implementation, the respective layers of the light-emitting function layer 140 may be sequentially deposited on the surface of the driving back plate 100 on which the first electrode 120 and the semiconductor layer 130 are formed by a deposition process, as shown in fig. 11 and 12.

Further, the light emitting substrate 10 obtained through the above-mentioned preparation process is subjected to an encapsulation process, that is, an encapsulation layer 160 is formed on the surface of the light emitting function layer 140 away from the first electrode 120, as shown in fig. 2 and fig. 3, so as to protect the formed light emitting device.

In a third aspect, the present disclosure also provides a display device, including the light-emitting substrate 10 provided in the first aspect. For example, the display device may be a display panel, a display screen, a virtual reality device, an augmented reality device, a projector, a mobile phone, a tablet computer, a notebook computer, a television, an electronic photo frame, a wearable device, and other devices having a display function, which is not limited in this embodiment.

For example, taking a virtual reality device or an augmented reality device as an example, the light-emitting substrate 10 may further include: specific structures of a planarization layer (OC) disposed on the surface of the encapsulation layer 160 of the light emitting substrate 10 and a lens array disposed on a side of the planarization layer away from the encapsulation layer 160 can be found in the related art, and will not be described in detail herein.

In the above description, details of the techniques such as patterning of the layers of the product are not described in detail. It will be appreciated by those skilled in the art that layers, regions, etc. of the desired shape may be formed by various technical means. In addition, in order to form the same structure, the person skilled in the art can also design a method which is not exactly the same as the method described above. Although the embodiments are described separately above, this does not mean that the measures in the embodiments cannot be used in advantageous combination.

In the description provided herein, numerous specific details are set forth. However, it is understood that embodiments of the application may be practiced without these specific details. In some instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description.

Additionally, one of ordinary skill in the art should understand that: the discussion of any embodiment above is merely exemplary in nature, and is not intended to intimate that the scope of the disclosure is limited to these examples; within the spirit of the present disclosure, features from the above embodiments or from different embodiments may also be combined, steps may be implemented in any order, and there are many other variations of different aspects of one or more embodiments of the present description as described above, which are not provided in detail for the sake of brevity.

While preferred embodiments of the present specification have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all changes and modifications that fall within the scope of the specification.

Claims (14)

1. A light-emitting substrate, comprising:

driving the back plate;

a first pixel defining layer disposed on the driving backplane, the first pixel defining layer having a plurality of opening regions; and

a light emitting device disposed at the opening region, the light emitting device including: the light-emitting diode comprises a first electrode, a light-emitting functional layer and a semiconductor film layer arranged between the first electrode and the light-emitting functional layer;

the first electrode at least covers the bottom surface and the side wall of the opening area, the material of the semiconductor film layer has a conductive state and a non-conductive state, the semiconductor film layer comprises a first functional unit in the non-conductive state, and the first functional unit covers the first electrode arranged on the side wall of the opening area.

2. The light-emitting substrate according to claim 1, wherein the semiconductor film layer further comprises a second functional unit in the conductive state, and the second functional unit covers the first electrode provided on the bottom surface of the opening region.

3. The light-emitting substrate according to claim 2, wherein the semiconductor film layer is a graphene thin film, the first functional unit is a graphene thin film in an intrinsic state, and the second functional unit is a graphene thin film subjected to a nonconductor process.

4. The light-emitting substrate as claimed in claim 1, wherein the semiconductor film layer has a thickness of 10 to 2000 angstroms.

5. The luminescent substrate according to claim 1, wherein the first electrode extends from the open region to a top of the first pixel defining layer, and wherein the first functional unit further covers a first electrode disposed at a target corner, the target corner comprising a corner between the open region sidewall and the top of the first pixel defining layer.

6. The light-emitting substrate according to claim 1, further comprising: a second pixel defining layer;

the second pixel defining layer is stacked on top of the first pixel defining layer and is positioned adjacent to a spaced region of the first electrode of the light emitting device.

7. The light-emitting substrate according to claim 6, wherein the light-emitting function layer comprises: a hole injection layer and a hole transport layer;

the thickness of the second pixel defining layer is at least greater than the sum of the thicknesses of the first electrode, the semiconductor film layer, the hole injection layer and the hole transport layer in a direction perpendicular to the driving backplane to block the hole injection layer and the hole transport layer of adjacent light emitting devices.

8. The light-emitting substrate according to claim 7, wherein the light-emitting function layer further comprises: a light-emitting layer and a second electrode;

the thickness of the second pixel defining layer is larger than the sum of the thicknesses of the first electrode, the semiconductor film layer and the light-emitting function layer along the direction perpendicular to the driving back plate so as to block the light-emitting function layers of the adjacent light-emitting devices.

9. The light-emitting substrate according to claim 6, wherein a material of the second pixel defining layer is an inorganic insulating material.

10. A method of fabricating a light-emitting substrate, the method comprising:

forming a first pixel defining layer on a driving backplane, the first pixel defining layer having a plurality of opening regions;

forming a first electrode in an opening region of the first pixel defining layer, the first electrode covering at least a bottom surface and a sidewall of the opening region;

forming a semiconductor film layer on the first electrode, wherein the material of the semiconductor film layer has a conductive state and a non-conductive state, the semiconductor film layer comprises a first functional unit in the non-conductive state, and the first functional unit covers the first electrode arranged at the side wall of the opening region;

and forming a light-emitting functional layer.

11. The method of claim 10, wherein forming a semiconductor film layer on the first electrode comprises:

forming a graphene film on the surface of the driving backboard on which the first electrode is formed;

and carrying out non-conductor processing on the graphene film in the target area to form the first functional unit.

12. The method of claim 11, wherein the non-conducting treatment of the graphene thin film of the target area comprises:

and carrying out surface treatment on the graphene film of the target area by using argon and/or hydrogen to generate hydrogenated graphene in the target area.

13. The method according to claim 10, further comprising, after forming a semiconductor film layer on the first electrode and before forming a light-emitting function layer:

forming a second pixel defining layer on top of the first pixel defining layer, the second pixel defining layer being located at a spaced region of the first electrodes of the adjacent light emitting devices.

14. A display device comprising the light-emitting substrate according to any one of claims 1 to 9.

Images