CN109244108B

CN109244108B - OLED display substrate, manufacturing method thereof and OLED display device

Info

Publication number: CN109244108B
Application number: CN201810996084.7A
Authority: CN
Inventors: 马国强; 柴媛媛; 孙阔; 汪杨鹏; 陈鹏; 唐国强; 代伟男
Original assignee: BOE Technology Group Co Ltd; Chengdu BOE Optoelectronics Technology Co Ltd
Current assignee: BOE Technology Group Co Ltd; Chengdu BOE Optoelectronics Technology Co Ltd
Priority date: 2018-08-29
Filing date: 2018-08-29
Publication date: 2020-11-03
Anticipated expiration: 2038-08-29
Also published as: CN109244108A

Abstract

The embodiment of the invention provides an OLED display substrate, a manufacturing method thereof and an OLED display device, wherein the OLED display substrate comprises: the substrate base plate, set up OLED device layer and the encapsulation layer that is used for encapsulating OLED device layer on the substrate base plate still include: a piezoelectric functional layer; the piezoelectric functional layer is arranged on one side of the packaging layer far away from the substrate and used for generating mechanical vibration under the action of an electric signal so as to generate ultrasonic waves or audible sound waves. According to the embodiment of the invention, the piezoelectric functional layer is arranged in the OLED display substrate, the ultrasonic wave and the audible sound wave are generated through the mechanical vibration of the piezoelectric functional layer, the screen sounding and fingerprint identification functions are realized by adopting the same structure, the occupied volume of the OLED display is reduced, and the requirement of the OLED display on lightness and thinness is met.

Description

OLED display substrate, manufacturing method thereof and OLED display device

Technical Field

The embodiment of the invention relates to the technical field of display, in particular to an OLED display substrate, a manufacturing method thereof and an OLED display device.

Background

An Organic Light-Emitting diode (OLED) Display is a Display different from a conventional Liquid Crystal Display (LCD) and has the advantages of active Light emission, good temperature characteristics, low power consumption, fast response, flexibility, ultra-lightness and thinness, low cost and the like. And thus has become one of the important developments of the new generation of display devices and receives increasing attention.

Adopt piezoelectric actuator to realize screen vocal function among the OLED display, adopt ultrasonic sensor to realize the fingerprint identification function, the inventor researches and discovers, if the OLED display realizes screen vocal function and fingerprint identification function simultaneously, need set up piezoelectric actuator and ultrasonic sensor simultaneously for the volume that the OLED display occupy is great, can't satisfy the demand that the OLED display is frivolous.

Disclosure of Invention

In order to solve the technical problems, embodiments of the present invention provide an OLED display substrate, a manufacturing method thereof, and an OLED display device, where the same structure disposed in the OLED display substrate is used to implement screen sound production and fingerprint identification functions, so as to reduce the volume occupied by the OLED display and meet the requirement of the OLED display for being light and thin.

In a first aspect, an embodiment of the present invention provides an OLED display substrate, including: the OLED display substrate comprises a substrate base plate, an OLED device layer arranged on the substrate base plate and an encapsulation layer used for encapsulating the OLED device layer, and further comprises: a piezoelectric functional layer;

the piezoelectric functional layer is arranged on one side of the packaging layer far away from the substrate base plate and used for generating mechanical vibration under the action of an electric signal so as to generate ultrasonic waves or audible sound waves.

Optionally, the piezoelectric functional layer comprises: a first electrode, a piezoelectric layer, and a second electrode;

the piezoelectric layer is disposed between the first electrode and the second electrode;

the first electrode is arranged on one side of the piezoelectric layer close to the substrate base plate or one side far away from the substrate base plate.

Optionally, the first electrode comprises: a first sub-electrode arranged in an M N array, the piezoelectric layer comprising: piezoelectric structures arranged in an M × N array;

and the orthographic projection of the first electrode on the substrate is superposed with the orthographic projection of the piezoelectric layer on the substrate, wherein M and N are positive integers.

Optionally, the second electrode comprises: a second sub-electrode arranged in an M × N array;

the orthographic projection of the first electrode on the substrate base plate is superposed with the orthographic projection of the second electrode on the substrate base plate.

Optionally, the second electrode comprises: a planar electrode;

the orthographic projection of the second electrode on the substrate covers the orthographic projection of the first electrode on the substrate.

Optionally, the first electrode and the second electrode are transparent electrodes, and the material for manufacturing the electrodes includes: indium tin oxide, nanotubes, or graphene;

the manufacturing material of the piezoelectric layer comprises: polyvinylidene fluoride.

Optionally, the OLED display substrate further includes: a buffer layer disposed between the encapsulation layer and the piezoelectric functional layer; and/or

The protective layer is arranged on one side, far away from the substrate base plate, of the piezoelectric functional layer.

Optionally, the OLED display substrate further includes: a drive detection circuit, a first wire and a second wire; the drive detection circuit includes: the driving sub-circuit, the detection sub-circuit, the first switch and the second switch;

the driving sub-circuit is connected with the first sub-electrode and the first switch and used for generating a first electric signal, and when the first switch is in a closed state, the piezoelectric structure is driven to generate mechanical vibration so as to generate ultrasonic waves; the second switch is used for generating a second electric signal, and when the first switch is in a closed state, the piezoelectric structure is driven to generate mechanical vibration so as to generate audible sound waves;

the detection sub-circuit is connected with the second sub-electrode and the second switch and is used for forming a fingerprint image according to the received ultrasonic waves reflected by the fingerprint when the second switch is in a closed state;

each first sub-electrode is connected with the driving sub-circuit through a first lead, and each second sub-electrode is connected with the detection sub-circuit through a second lead.

the detection sub-circuit is connected with the first sub-electrode and the second switch and is used for forming a fingerprint image according to the received ultrasonic waves reflected by the fingerprint when the second switch is in a closed state;

each first sub-electrode is connected with the driving sub-circuit through a first lead and is connected with the detection sub-circuit through a second lead.

Optionally, the first lead and the first electrode are disposed in the same layer, and the second lead and the second electrode are disposed in the same layer.

In a second aspect, an embodiment of the present invention further provides an OLED display device, including: the OLED display substrate is provided.

In a third aspect, an embodiment of the present invention further provides a method for manufacturing an OLED display substrate, including:

providing a substrate base plate;

forming an OLED device layer on the substrate base plate;

forming an encapsulation layer for encapsulating the OLED device layer on the OLED device layer;

and forming a piezoelectric functional layer on the packaging layer, wherein the piezoelectric packaging layer is used for generating mechanical vibration under the action of an electric signal so as to generate ultrasonic waves or audible sound waves.

Optionally, the forming a piezoelectric functional layer on the encapsulation layer includes:

forming a first electrode, a piezoelectric layer, and a second electrode on the encapsulation layer to form a piezoelectric functional layer, wherein the piezoelectric layer is disposed between the first electrode and the second electrode.

Optionally, forming the piezoelectric layer comprises:

coating an insulating film, and forming a piezoelectric channel through an exposure and development process;

a piezoelectric layer is formed in the piezoelectric channel by an inkjet printing process.

Optionally, before forming the piezoelectric functional layer on the encapsulation layer, the method further includes:

forming a buffer layer on the encapsulation layer;

after the forming the piezoelectric functional layer on the encapsulation layer, the method further comprises:

forming a protective layer on the piezoelectric functional layer.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

Drawings

The accompanying drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the example serve to explain the principles of the invention and not to limit the invention.

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

fig. 2 is a schematic structural diagram of a piezoelectric functional layer provided in an embodiment of the present invention;

FIG. 3 is a first side view of an OLED display substrate according to an embodiment of the present invention;

FIG. 4 is a side view of a first electrode provided by an embodiment of the present invention;

fig. 5 is a top view of a piezoelectric layer provided by an embodiment of the invention;

FIG. 6 is a first top view of a second electrode according to an embodiment of the present invention;

FIG. 7 is a second side view of the OLED display substrate according to the embodiment of the present invention;

FIG. 8 is a second top view of a second electrode according to an embodiment of the present invention;

fig. 9 is a schematic structural diagram of a second OLED display substrate according to an embodiment of the present invention;

FIG. 10 is a first perspective view of an OLED display substrate according to an embodiment of the present invention;

FIG. 11 is an equivalent circuit diagram of the OLED display substrate corresponding to FIG. 10;

FIG. 12 is a second perspective view of an OLED display substrate according to an embodiment of the present invention;

FIG. 13 is an equivalent circuit diagram of the OLED display substrate corresponding to FIG. 12;

fig. 14 is a flowchart of a method for manufacturing an OLED display substrate according to an embodiment of the invention;

fig. 15A is a first schematic view illustrating a manufacturing method of an OLED display substrate according to an embodiment of the invention;

fig. 15B is a second schematic view illustrating a manufacturing method of an OLED display substrate according to an embodiment of the invention;

fig. 15C is a third schematic view illustrating a manufacturing method of an OLED display substrate according to an embodiment of the invention;

fig. 15D is a fourth schematic view illustrating a manufacturing method of an OLED display substrate according to an embodiment of the invention;

fig. 15E is a fifth schematic view illustrating a manufacturing method of an OLED display substrate according to an embodiment of the invention;

fig. 15F is a sixth schematic view illustrating a manufacturing method of an OLED display substrate according to an embodiment of the invention;

fig. 15G is a seventh schematic view illustrating a manufacturing method of an OLED display substrate according to an embodiment of the invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that the embodiments and features of the embodiments in the present application may be arbitrarily combined with each other without conflict.

The steps illustrated in the flow charts of the figures may be performed in a computer system such as a set of computer-executable instructions. Also, while a logical order is shown in the flow diagrams, in some cases, the steps shown or described may be performed in an order different than here.

Unless defined otherwise, technical or scientific terms used in the disclosure of the embodiments of the present invention should have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. The use of "first," "second," and similar language in the embodiments of the present invention does not denote any order, quantity, or importance, but rather the terms "first," "second," and similar language are used to distinguish one element from another. The word "comprising" or "comprises", and the like, means that the element or item listed before the word covers the element or item listed after the word and its equivalents, but does not exclude other elements or items. The terms "connected" or "coupled" and the like are not restricted to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships may also be changed accordingly.

Example one

Fig. 1 is a schematic structural diagram of an OLED display substrate according to an embodiment of the present invention, as shown in fig. 1, an embodiment of the present invention provides an OLED display substrate, including: the OLED display substrate comprises a substrate base plate 10, an OLED device layer 20 arranged on the substrate base plate 10 and an encapsulation layer 30 for encapsulating the OLED device layer 20, and further comprises: the piezoelectric functional layer 40.

Specifically, the piezoelectric functional layer 40 is disposed on a side of the encapsulation layer 30 away from the substrate 10, and is configured to generate mechanical vibration under the action of an electrical signal to generate an ultrasonic wave or an audible sound wave.

Alternatively, the material for manufacturing the base substrate 10 includes: glass, plastic, quartz, polyimide, etc., which are not limited in this respect.

Specifically, the OLED device layer 20 includes: thin film transistor and positive pole, luminescent layer and the negative pole of setting on thin film transistor, wherein, thin film transistor includes: the thin film transistor comprises a gate electrode, a gate insulating layer, an active layer, an interlayer dielectric layer and a source drain electrode, wherein the drain electrode of the thin film transistor is connected with the anode.

Alternatively, the thin film transistor may have a top gate structure or a bottom gate structure, which is not limited in this embodiment of the present invention.

Optionally, the material for manufacturing the encapsulation layer 30 includes: tetrafluoroethylene to protect the OLED device layers from damage.

In the present embodiment, the piezoelectric functional layer 40 is used to generate mechanical vibration under the action of an electrical signal to generate ultrasonic waves or audible sound waves. Wherein, the mechanical vibration of piezoelectricity functional layer is as the excitation source of screen sound production, and then piezoelectricity functional layer generates audible sound wave, can realize the function of screen sound production, and wherein, the screen sound production includes: full screen sounding and/or earpiece sounding; the piezoelectric functional layer generates ultrasonic waves, and the purpose of fingerprint identification can be achieved by arranging a circuit structure to identify ultrasonic signals reflected by fingerprints.

In addition, the piezoelectric functional layer 40 may also implement touch detection in combination with touch feedback to increase user experience.

The OLED display substrate provided by the embodiment of the invention comprises: the substrate base plate, set up OLED device layer and the encapsulation layer that is used for encapsulating OLED device layer on the substrate base plate still include: a piezoelectric functional layer; the piezoelectric functional layer is arranged on one side of the packaging layer far away from the substrate and used for generating mechanical vibration under the action of an electric signal so as to generate ultrasonic waves or audible sound waves. According to the embodiment of the invention, the piezoelectric functional layer is arranged in the OLED display substrate, the ultrasonic wave and the audible sound wave are generated through the mechanical vibration of the piezoelectric functional layer, the screen sounding and fingerprint identification functions are realized by adopting the same structure, the occupied volume of the OLED display is reduced, and the requirement of the OLED display on lightness and thinness is met.

Optionally, fig. 2 is a schematic structural diagram of a piezoelectric functional layer provided in an embodiment of the present invention, and as shown in fig. 2, the piezoelectric functional layer 40 provided in the embodiment of the present invention includes: a first electrode 41, a piezoelectric layer 42 and a second electrode 43.

Here, the piezoelectric layer 42 is disposed between the first electrode 41 and the second electrode 43, and the first electrode 41 is disposed on a side of the piezoelectric layer 42 close to the base substrate 10 or a side far from the base substrate 10.

Optionally, in order not to affect the display effect of the OLED display substrate, the first electrode 41 is a transparent electrode, and the material for making the transparent electrode includes: transparent conductive materials such as indium tin oxide, carbon nanotubes or graphene.

Optionally, the piezoelectric layer 42 is made of a piezoelectric material, wherein the piezoelectric material includes: polyvinylidene fluoride, aluminum nitride AlN, or a lead zirconate titanate-based composite oxide having a perovskite structure.

Preferably, to realize the flexible display substrate, the material of the piezoelectric layer 42 includes: polyvinylidene fluoride.

Optionally, in order not to affect the display effect of the OLED display substrate, the second electrode 43 is a transparent electrode, and the material of the transparent electrode includes: indium tin oxide, carbon nanotubes, and other transparent conductive materials.

The materials for manufacturing the first electrode 41 and the second electrode 43 may be the same or different, and this is not limited in the embodiment of the present invention.

Specifically, the positions of the first electrode 41 and the second electrode 43 are not limited in this embodiment of the present invention, that is, the first electrode 41 may be disposed on a side of the piezoelectric layer 42 close to the substrate 10, the second electrode 43 may be disposed on a side of the piezoelectric layer 42 away from the substrate 10, or the first electrode 41 may be disposed on a side of the piezoelectric layer 42 away from the substrate 10, and the second electrode 43 may be disposed on a side of the piezoelectric layer 42 close to the substrate 10.

Optionally, as an implementation manner, fig. 3 is a first side view of the OLED display substrate provided in the embodiment of the present invention, fig. 4 is a side view of the first electrode provided in the embodiment of the present invention, fig. 5 is a top view of the piezoelectric layer provided in the embodiment of the present invention, and fig. 6 is a first top view of the second electrode provided in the embodiment of the present invention, as shown in fig. 3 to 6, the first electrode 41 in the OLED display substrate provided in the embodiment of the present invention includes: the first sub-electrodes 410 arranged in an M × N array, the piezoelectric layer 42 includes: the piezoelectric structures 420 arranged in an M × N array, the second electrode 43 includes: and a second sub-electrode 430 arranged in an M × N array.

Specifically, an orthographic projection of the first electrode 41 on the substrate 10 coincides with an orthographic projection of the piezoelectric layer 42 on the substrate 10, and an orthographic projection of the first electrode 41 on the substrate 10 coincides with an orthographic projection of the second electrode 43 on the substrate 10, that is, the first sub-electrode 410, the piezoelectric structure 420 and the second sub-electrode 430 correspond to each other one by one, in this embodiment, the corresponding first sub-electrode 410, the corresponding piezoelectric structure 420 and the corresponding second sub-electrode 430 are made into a vibration unit, that is, the piezoelectric functional layer provided in the embodiment of the present invention includes: and vibration units arranged in an M × N array.

In fig. 3 to 6, M is 3, and N is 3, which are examples, and the present invention is not limited to this.

Specifically, when the voltage signals are applied to the first sub-electrode 410 and the second sub-electrode 430, the piezoelectric structure 420 may generate mechanical vibration, and when the voltage signals are different between the first sub-electrode 410 and the second sub-electrode 430, the strength of the mechanical vibration generated by the piezoelectric structure may be different.

The OLED display substrate comprises a substrate, a first electrode, a second electrode, a third electrode, a fourth electrode, a fifth electrode, a sixth electrode, a fifth electrode, a sixth electrode. When M is not 1 with N simultaneously, OLED display panel not only can realize the full screen sound production, can also realize the earphone sound production, and is specific, and OLED display substrate can realize the earphone sound production through the mechanical vibration of the vibration unit near only adjusting the earphone position, and OLED display substrate can also realize the full screen sound production through the mechanical vibration of all vibration units.

Optionally, as another implementation manner, fig. 7 is a second side view of the OLED display substrate provided in the embodiment of the present invention, and fig. 8 is a second top view of the second electrode provided in the embodiment of the present invention, as shown in fig. 4, fig. 5, fig. 7, and fig. 8, the first electrode 41 in the OLED display substrate provided in the embodiment of the present invention includes: the first sub-electrodes 410 arranged in an M × N array, the piezoelectric layer 42 includes: the piezoelectric structures 420 arranged in an M × N array, the second electrode 43 includes: a planar electrode.

Specifically, an orthographic projection of the first electrode 41 on the substrate base plate 10 coincides with an orthographic projection of the piezoelectric layer 42 on the substrate base plate 10; specifically, the orthographic projection of the second electrode 43 on the base substrate 10 covers the orthographic projection of the first electrode 41 on the base substrate 10.

In addition, when the second electrode 43 is a planar electrode, the second electrode is grounded.

Optionally, fig. 9 is a schematic structural diagram of a second OLED display substrate provided in the embodiment of the present invention, and as shown in fig. 9, the OLED display substrate provided in the embodiment of the present invention further includes: a buffer layer 50.

Specifically, the buffer layer 50 is disposed between the encapsulating layer 30 and the piezoelectric functional layer 40; the OLED display substrate is used for avoiding damage to the packaging layer when the piezoelectric functional layer is manufactured, and the reliability of the OLED display substrate can be improved.

Optionally, the material for the buffer layer 50 includes: the embodiments of the present invention are not limited in any way to silicon oxide, silicon nitride, or a composite of silicon oxide and silicon nitride.

Optionally, as shown in fig. 9, the OLED display substrate provided in the embodiment of the present invention further includes: and a protective layer 60.

Specifically, the protective layer 60 is disposed on a side of the piezoelectric functional layer 40 away from the substrate 10, and is used for protecting the piezoelectric functional layer from being damaged, which can also improve the reliability of the OLED display substrate.

Optionally, the material of the protective layer 60 includes: the embodiments of the present invention are not limited in any way to silicon oxide, silicon nitride, or a composite of silicon oxide and silicon nitride.

Fig. 9 illustrates an example in which the OLED display substrate includes both the buffer layer and the protective layer.

Optionally, as an implementation manner, when the second electrode 43 includes the second sub-electrodes 430 arranged in an array, fig. 10 is a first oblique view of the OLED display substrate provided in the embodiment of the present invention, fig. 11 is an equivalent circuit diagram of the OLED display substrate corresponding to fig. 10, and as shown in fig. 10 and fig. 11, the OLED display substrate provided in the embodiment of the present invention further includes: a drive detection circuit 70, a first wire L1, and a second wire L2; the drive detection circuit 70 includes: a drive sub-circuit 71, a detection sub-circuit 72, a first switch SW1 and a second switch SW 2.

Specifically, the driving sub-circuit 71 is connected to the first sub-electrode 410 and the first switch SW1, and is configured to generate a first electrical signal, and when the first switch SW1 is in a closed state, the piezoelectric structure 420 is driven to generate mechanical vibration to generate ultrasonic waves; the driving sub-circuit 71 is further configured to generate a second electrical signal, and when the first switch SW1 is in a closed state, the piezoelectric structure 420 is driven to generate mechanical vibration to generate an audible sound wave; and a detection sub-circuit 72 connected to the second sub-electrode 430 and the second switch SW2, for forming a fingerprint image according to the received ultrasonic waves reflected by the fingerprint when the second switch SW2 is in a closed state.

Wherein each first sub-electrode 410 is connected to the driving sub-circuit 71 through a first conducting line L1, and each second sub-electrode 430 is connected to the detecting sub-circuit 72 through a second conducting line L2.

Specifically, as shown in fig. 11, the first switch SW1 has a first terminal connected to the ground GND, a second terminal connected to the first sub-electrode 410 and the driving sub-circuit 71, respectively, and the second switch SW2 has a first terminal connected to the ground GND, and a second terminal connected to the second sub-electrode 430 and the detecting sub-circuit 72, respectively.

Specifically, the first conducting wire L1 and the first electrode 41 are disposed in the same layer, and the second conducting wire L2 and the second electrode 43 are disposed in the same layer.

Fig. 11 is a circuit diagram illustrating connection of one vibration unit, and the connection manner of each vibration unit in the piezoelectric structure layer is the same as that of fig. 11.

Optionally, as another implementation manner, fig. 12 is a second oblique view of the OLED display substrate according to an embodiment of the present invention, and fig. 13 is an equivalent circuit diagram of the OLED display substrate corresponding to fig. 12, as shown in fig. 12 and fig. 13, further including: a drive detection circuit 70, a first wire L1, and a second wire L2; the drive detection circuit 70 includes: a drive sub-circuit 71, a detection sub-circuit 72, a first switch SW1 and a second switch SW 2.

Specifically, the driving sub-circuit 71 is connected to the first sub-electrode 410 and the first switch SW1, and is configured to generate a first electrical signal, and when the first switch SW1 is in a closed state, the piezoelectric structure 420 is driven to generate mechanical vibration to generate ultrasonic waves; the driving sub-circuit 71 is further configured to generate a second electrical signal, and when the first switch SW1 is in a closed state, the piezoelectric structure 420 is driven to generate mechanical vibration to generate an audible sound wave; and a detection sub-circuit 72 connected to the first sub-electrode 410 and the second switch SW2, for forming a fingerprint image according to the received ultrasonic waves reflected by the fingerprint when the second switch SW2 is in a closed state.

Wherein each first sub-electrode 410 is connected to the driving sub-circuit 71 through a first conducting line L1 and connected to the detecting sub-circuit 72 through a second conducting line L2.

Specifically, as shown in fig. 13, the first terminal of the first switch SW1 is connected to the ground GND and the first sub-electrode 410, the second terminal thereof is connected to the driving sub-circuit 71, the first terminal of the second switch SW2 is connected to the ground GND and the second sub-electrode 430, and the second terminal thereof is connected to the detection sub-circuit 72.

Fig. 13 is a circuit diagram illustrating a connection between one first sub-electrode and a corresponding piezoelectric structure, and a portion of the second electrode corresponding to the first sub-electrode.

Specifically, the first wire L1 and the second wire L2 are disposed at the same layer as the first electrode 41.

The working principle of the OLED display substrate provided in the embodiment of the present invention is further described below with reference to fig. 11 and fig. 13, specifically:

when the driving sub-circuit 71 generates the first electrical signal, the fingerprint recognition function is realized, specifically, in the first stage, the driving sub-circuit 71 generates the first electrical signal, the first switch SW1 is in a closed state, the second switch SW2 is in an open state, and at this time, the signal of the first sub-electrode 410 is the first electrical signal; in the second stage, the first switch SW1 is in an open state, the second switch SW2 is in a closed state, at this time, the signal of the first sub-electrode 410 still maintains the first electric signal, the signal of the second sub-electrode 430 is a ground signal, and the piezoelectric structure 420 generates mechanical vibration under the driving of the first electric signal to generate ultrasonic waves; when the OLED display substrate is pressed by the fingerprint, the generated ultrasonic waves are reflected back by the fingerprint, and the detection sub-circuit receives the ultrasonic waves reflected by the fingerprint to form a fingerprint image.

Specifically, when the fingerprint identification function is realized, the ultrasonic waves reflected by the fingerprint can cause the potential of the first sub-electrode and the potential of the second sub-electrode to change, and the detection sub-circuit analyzes and processes the potential according to the potential change of the first sub-electrode and the potential change of the second sub-electrode, so that the fingerprint image is obtained.

In addition, the OLED display substrate provided in this embodiment can also implement touch detection, and when implementing touch detection, the detection sub-circuit only needs to detect a position where an electrical signal changes due to an ultrasonic wave reflected by a fingerprint, and the position where the electrical signal changes is a position of touch that needs to be detected.

When the driving sub-circuit 71 generates the second electrical signal, a screen sounding is realized, specifically, the first switch SW1 is in an open state, the second switch SW2 is in a closed state, and the signal of the first sub-electrode 410 is the second electrical signal, so that the piezoelectric structure 420 generates mechanical vibration to generate an audible sound wave, wherein the audible sound wave is in a range of 20 to 20000 HZ. Specifically, when the first switch SW1 connected to the piezoelectric structure located near the earpiece position is in an on state, and the first switches SW1 connected to the piezoelectric structures located at the other positions are in an off state, that is, at this time, the driving sub-circuit 71 only controls the piezoelectric structures near the earpiece position, and the OLED display substrate realizes the sound production of the earpiece; when the first switch SW1 connected to all the piezoelectric structures in the OLED display substrate is in an on state and the second switch SW2 is in an off state, the driving sub-circuit 71 can control all the piezoelectric structures, and the OLED display substrate realizes full-screen sound production.

Example two

Based on the inventive concept of the above embodiment, an embodiment of the present invention further provides a method for manufacturing an OLED display substrate, fig. 14 is a flowchart of the method for manufacturing the OLED display substrate according to the embodiment of the present invention, and as shown in fig. 14, the method for manufacturing the OLED display substrate according to the embodiment of the present invention specifically includes the following steps:

step 100, a substrate is provided.

Optionally, the substrate base plate is made of a material including: glass, plastic, quartz, polyimide, etc., which are not limited in this respect.

Step 200, forming an OLED device layer on the substrate base plate.

Specifically, the OLED device layer comprises: thin film transistor and positive pole, luminescent layer and the negative pole of setting on thin film transistor, wherein, thin film transistor includes: the thin film transistor comprises an active layer, a gate electrode, a gate insulating layer, an interlayer dielectric layer and a source drain electrode, wherein the drain electrode of the thin film transistor is connected with the anode.

And 300, forming an encapsulation layer for encapsulating the OLED device layer on the OLED device layer.

Optionally, the material for forming the encapsulation layer includes: tetrafluoroethylene to protect the OLED device layers from damage.

Step 400, forming a piezoelectric functional layer on the packaging layer.

The piezoelectric packaging layer is used for generating mechanical vibration under the action of an electric signal so as to generate ultrasonic waves or audible sound waves.

In this embodiment, the piezoelectric functional layer is configured to generate mechanical vibration under the action of an electrical signal to generate an ultrasonic wave or an audible sound wave, the piezoelectric functional layer generates the audible sound wave to realize a screen sounding function, and the piezoelectric functional layer generates the ultrasonic wave to achieve a fingerprint identification purpose by setting an ultrasonic signal reflected by a circuit structure fingerprint.

In addition, the piezoelectric functional layer can be combined with touch feedback to realize touch detection so as to increase user experience.

The manufacturing method of the OLED display substrate provided by the embodiment of the invention comprises the following steps: providing a substrate base plate; forming an OLED device layer on a substrate; forming an encapsulation layer for encapsulating the OLED device layer on the OLED device layer; and forming a piezoelectric functional layer on the packaging layer, wherein the piezoelectric packaging layer is used for generating mechanical vibration under the action of an electric signal so as to generate ultrasonic waves or audible sound waves. According to the embodiment of the invention, the piezoelectric functional layer is arranged in the OLED display substrate, the ultrasonic wave and the audible sound wave are generated through the mechanical vibration of the piezoelectric functional layer, the screen sounding and fingerprint identification functions are realized by adopting the same structure, the occupied volume of the OLED display is reduced, and the requirement of the OLED display on lightness and thinness is met.

Optionally, step 400 specifically includes: forming a first electrode, a piezoelectric layer, and a second electrode on the encapsulation layer to form a piezoelectric functional layer, wherein the piezoelectric layer is disposed between the first electrode and the second electrode.

Optionally, as an embodiment, step 400 may include: and sequentially forming a first electrode, a piezoelectric layer and a second electrode on the packaging layer.

Optionally, as another embodiment, step 400 may include: and sequentially forming a second electrode, a piezoelectric layer and a first electrode on the packaging layer.

Optionally, in order not to affect the display effect of the OLED display substrate, the first electrode is a transparent electrode, and the material for manufacturing the first electrode includes: transparent conductive materials such as indium tin oxide, carbon nanotubes or graphene.

Optionally, the piezoelectric layer is made of a piezoelectric material, wherein the piezoelectric material includes: polyvinylidene fluoride, aluminum nitride AlN, or a lead zirconate titanate-based composite oxide having a perovskite structure.

Preferably, in order to realize the flexible display substrate, the piezoelectric layer is made of a material including: polyvinylidene fluoride.

Optionally, in order not to affect the display effect of the OLED display substrate, the second electrode is a transparent electrode, and the material for manufacturing the second electrode includes: indium tin oxide, carbon nanotubes, and other transparent conductive materials.

It should be noted that the first electrode and the second electrode may be made of the same material or different materials, and the embodiment of the present invention is not limited in any way.

Specifically, the first electrode includes: a first sub-electrode arranged in an M N array, the piezoelectric layer comprising: an array of M x N piezoelectric structures, the second electrode comprising: the second sub-electrodes arranged in an M × N array, or the second electrodes, include: a planar electrode.

In this embodiment, the OLED display substrate further includes: drive detection circuit, first wire and second wire, wherein, drive detection circuit includes: the driving sub-circuit is connected with the first switch, and the second switch is connected with the detection sub-circuit.

Alternatively, when the second electrode includes: when the sub-electrodes are arranged in an array, forming the first electrode includes: forming a first electrode and a first lead, wherein the first sub-electrode is connected with the driving sub-circuit through the first lead; forming the second electrode includes: and forming a second electrode and a second lead, wherein the second sub-electrode is connected with the driving sub-circuit through the second lead.

Specifically, a first metal film is deposited by a Plasma Enhanced Chemical Vapor Deposition (PECVD) process, a first electrode and a first wire are formed by a patterning process, a second metal film is deposited by a PECVD process, and a second electrode and a second wire are formed by a patterning process.

It should be noted that the patterning process includes: photoresist coating, exposure, development, etching, photoresist stripping and the like.

Alternatively, when the second electrode includes: in the case of a planar electrode, forming the first electrode includes: and forming a first electrode, a first lead and a second lead, wherein the first sub-electrode is connected with the driving sub-circuit through the first lead and is connected with the detection sub-circuit through the second lead.

Specifically, a first metal film is deposited by a Plasma Enhanced Chemical Vapor Deposition (PECVD) process, and a first electrode, a first wire, and a second wire are formed by a patterning process.

Optionally, in order to ensure the performance of the OLED display substrate, the forming the piezoelectric layer includes: coating an insulating film, and forming a piezoelectric channel through an exposure and development process; a piezoelectric layer is formed in the piezoelectric channel by an inkjet printing process.

Alternatively, an insulating film may be coated on the first electrode, and an insulating film may also be coated on the second electrode.

Alternatively, the insulating film may be made of polyimide, silicon oxide, silicon nitride, or a composite of silicon oxide and silicon nitride.

Specifically, the thickness of the insulating film is equal to the sum of the thicknesses of the first electrode and the piezoelectric layer.

In the embodiment, the shape of the piezoelectric layer is ensured by the piezoelectric layer in the piezoelectric channel, and the problem that piezoelectric materials are not easy to shape when the piezoelectric layer is formed by an ink-jet printing process is avoided, so that the piezoelectric structures of adjacent piezoelectric structures are connected to influence the screen sounding and finger identification functions of the OLED display substrate.

Optionally, before step 400, the method for manufacturing an OLED display substrate according to an embodiment of the present invention further includes: a buffer layer is formed on the encapsulation layer.

Optionally, the buffer layer is made of a material including: the embodiments of the present invention are not limited in any way to silicon oxide, silicon nitride, or a composite of silicon oxide and silicon nitride.

Optionally, after step 400, the method for manufacturing an OLED display substrate according to the embodiment of the present invention further includes: a protective layer is formed on the piezoelectric functional layer.

Optionally, the material for making the protective layer includes: the embodiments of the present invention are not limited in any way to silicon oxide, silicon nitride, or a composite of silicon oxide and silicon nitride.

The method for manufacturing the OLED display substrate according to the embodiment of the present invention is further described with reference to fig. 15A to 15G by taking an example that the first electrode is disposed on a side of the piezoelectric layer close to the substrate and the second electrode includes second sub-electrodes arranged in an array.

Step 510, forming an OLED device layer 20 and an encapsulation layer 30 on the substrate 10 in sequence, as shown in fig. 15A.

Step 520, a buffer layer 50 is formed on the encapsulation layer 30, as shown in fig. 15B.

Specifically, a buffer film is deposited on the encapsulation layer 30, and the buffer layer 50 is formed through a patterning process.

Step 530, forming a first electrode and a first conductive line (not shown) including the first sub-electrodes 410 arranged in an array on the buffer layer 50, as shown in fig. 15C.

Step 540, an insulating film 80 is coated on the first electrode, and a groove 81 exposing the first sub-electrode 410 is formed through an exposure and development process, as shown in fig. 15D.

Wherein the thickness of the insulating film 80 is equal to the sum of the thicknesses of the first electrode and the piezoelectric layer.

Step 550, forming a piezoelectric layer comprising an array of piezoelectric structures 420 in the recess 81 by an inkjet printing process, as shown in fig. 15E.

Step 560, forming a second electrode and a second conductive line (not shown in the figure) comprising the second sub-electrodes 430 arranged in an array on the piezoelectric layer, as shown in fig. 15F.

Step 570, form a protective layer 60 on the second electrode, as shown in fig. 15G.

Specifically, a protective film is deposited on the second electrode, and a protective layer is formed through a patterning process.

It should be noted that, when the second electrode includes a planar electrode, the difference between the method includes step 530 and step 560, where the step 530 corresponds to forming the first electrode including the first sub-electrodes 410 arranged in an array, the first conducting wire and the second conducting wire on the buffer layer 50, and the step 560 corresponds to forming the planar electrode on the piezoelectric material, where a projection of the planar electrode on the substrate covers a front projection of the first electrode on the substrate, and no further description is given here in the embodiment of the present invention.

EXAMPLE III

Based on the inventive concept of the above embodiments, an embodiment of the present invention further provides an OLED display device, including: and the OLED display substrate.

The OLED display substrate provided in the first embodiment is similar in implementation principle and implementation effect, and is not described herein again.

Specifically, the OLED display device may be: the OLED display panel comprises any product or component with a display function, such as an OLED panel, a mobile phone, a tablet computer, a television, a display, a notebook computer, a digital photo frame, a navigator and the like.

The drawings of the embodiments of the invention only relate to the structures related to the embodiments of the invention, and other structures can refer to common designs.

In the drawings used to describe embodiments of the invention, the thickness and dimensions of layers or microstructures are exaggerated for clarity. It will be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" or "under" another element, it can be "directly on" or "under" the other element or intervening elements may be present.

Without conflict, features of embodiments of the present invention, that is, embodiments, may be combined with each other to arrive at new embodiments.

Although the embodiments of the present invention have been described above, the above description is only for the convenience of understanding the present invention, and is not intended to limit the present invention. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. An OLED display substrate, comprising: the OLED display substrate comprises a substrate base plate, an OLED device layer arranged on the substrate base plate and an encapsulation layer used for encapsulating the OLED device layer, and further comprises: a piezoelectric functional layer;

the piezoelectric functional layer is arranged on one side, far away from the substrate base plate, of the packaging layer and used for generating mechanical vibration under the action of the first electric signal to generate ultrasonic waves and achieve a fingerprint identification function, and the piezoelectric functional layer is further used for generating mechanical vibration under the action of the second electric signal to generate audible sound waves and achieve full-screen sounding or earphone sounding.

2. The OLED display substrate of claim 1, wherein the piezoelectric functional layer comprises: a first electrode, a piezoelectric layer, and a second electrode;

3. The OLED display substrate of claim 2, wherein the first electrode comprises: a first sub-electrode arranged in an M N array, the piezoelectric layer comprising: piezoelectric structures arranged in an M × N array;

4. The OLED display substrate of claim 3, wherein the second electrode comprises: a second sub-electrode arranged in an M × N array;

5. The OLED display substrate of claim 3, wherein the second electrode comprises: a planar electrode;

6. The OLED display substrate of claim 2, wherein the first and second electrodes are transparent electrodes made of a material comprising: indium tin oxide, carbon nanotubes, or graphene;

7. The OLED display substrate of claim 1, further comprising: a buffer layer disposed between the encapsulation layer and the piezoelectric functional layer; and/or

8. The OLED display substrate of claim 4, further comprising: a drive detection circuit, a first wire and a second wire; the drive detection circuit includes: the driving sub-circuit, the detection sub-circuit, the first switch and the second switch;

9. The OLED display substrate of claim 5, further comprising: a drive detection circuit, a first wire and a second wire; the drive detection circuit includes: the driving sub-circuit, the detection sub-circuit, the first switch and the second switch;

each first sub-electrode is connected with the driving sub-circuit through a first lead and connected with the detection sub-circuit through a second lead.

10. The OLED display substrate of claim 8, wherein the first conductive line is disposed on the same layer as the first electrode, and the second conductive line is disposed on the same layer as the second electrode.

11. An OLED display device, comprising: an OLED display substrate as claimed in any one of claims 1 to 10.

12. A manufacturing method of an OLED display substrate is characterized by comprising the following steps:

providing a substrate base plate;

forming an OLED device layer on the substrate base plate;

and forming a piezoelectric functional layer on the packaging layer, wherein the piezoelectric functional layer is used for generating mechanical vibration under the action of a first electric signal to generate ultrasonic waves and realize a fingerprint identification function, and is also used for generating mechanical vibration under the action of a second electric signal to generate audible sound waves and realize full-screen sounding or earphone sounding.

13. The method of claim 12, wherein forming a piezoelectric functional layer on the encapsulation layer comprises:

14. The method of claim 13, wherein forming the piezoelectric layer comprises:

15. The method of claim 12, wherein prior to forming a piezoelectric functional layer on the encapsulation layer, the method further comprises:

forming a buffer layer on the encapsulation layer;

forming a protective layer on the piezoelectric functional layer.