CN108493218B

CN108493218B - Pressure-sensitive touch display panel, preparation method thereof and display device

Info

Publication number: CN108493218B
Application number: CN201810277835.XA
Authority: CN
Inventors: 李晓虎
Original assignee: BOE Technology Group Co Ltd
Current assignee: BOE Technology Group Co Ltd
Priority date: 2018-03-30
Filing date: 2018-03-30
Publication date: 2021-04-06
Anticipated expiration: 2038-03-30
Also published as: CN108493218A

Abstract

The disclosure provides a pressure-sensitive touch display panel, a preparation method thereof and a display device, and belongs to the technical field of display. The pressure-sensitive touch display panel includes: the TFT back plate is provided with a pixel area and a shielding area which are arranged at intervals; the organic light-emitting device is arranged on the TFT backboard and is positioned in the pixel area; the touch unit is located in the shading area, wherein the touch unit comprises: a first electrode; a second electrode; a layer of piezoelectric material disposed between the first electrode and the second electrode. The piezoelectric material layer is arranged between the two electrodes of the touch unit, so that the pressure sensor embedded in the touch display panel can be formed in the touch display panel, the purpose of reducing the overall thickness of the display device is achieved, and the effects of detecting screen pressure and touch can be achieved.

Description

Pressure-sensitive touch display panel, preparation method thereof and display device

Technical Field

The disclosure relates to the technical field of display, in particular to a pressure-sensitive touch display panel, a preparation method of the pressure-sensitive touch display panel and a display device.

Background

In recent years, touch technology is more and more widely applied to display devices of various sizes, and as a display screen of a novel man-machine interaction input mode, a touch screen is simpler, more direct and more convenient to input compared with the traditional modes of a display, a keyboard and a mouse.

In the pressure Touch (3D-Touch) technology, force sensors are arranged at four corners of a screen, and can sense pressing force (such as tapping, and pressing), so that different functions can be realized based on different forces, and user experience is improved. In order to provide the touch and pressure sensing effect for the screen, it is usually necessary to additionally provide a touch screen layer outside the display screen, which increases the overall thickness of the display device.

Therefore, there is still a need for improvement in the prior art solutions.

It is to be noted that the information disclosed in the above background section is only for enhancement of understanding of the background of the present disclosure, and thus may include information that does not constitute prior art known to those of ordinary skill in the art.

Disclosure of Invention

The present disclosure is directed to an array substrate, a method for manufacturing the same, and a display device, so as to overcome, at least to a certain extent, a problem that a touch screen is additionally disposed outside a display screen to increase the thickness of the whole display device in the related art.

Additional features and advantages of the disclosure will be set forth in the detailed description which follows, or in part will be learned by practice of the disclosure.

According to an aspect of the present disclosure, there is provided a pressure-sensitive touch display panel including:

the TFT back plate is provided with a pixel area and a shielding area which are arranged at intervals;

the organic light-emitting device is arranged on the TFT backboard and is positioned in the pixel area;

the touch control unit is positioned in the shielding area;

wherein the touch unit comprises:

a first electrode;

a second electrode proximate to the TFT backplane; and

a layer of piezoelectric material disposed between the first electrode and the second electrode.

In one exemplary embodiment of the present disclosure, the organic light emitting device includes:

a third electrode disposed on the TFT backplane;

a fourth electrode; and

an organic functional layer disposed between the third electrode and the fourth electrode.

In an exemplary embodiment of the present disclosure, further comprising:

a pixel defining layer disposed on the TFT backplane;

the pixel definition layer comprises pixel spacers and openings which are distributed at intervals, the pixel spacers are located in the shielding area, the openings are located in the pixel area, and the organic light-emitting devices are arranged at the openings.

In an exemplary embodiment of the disclosure, the second electrode and the fourth electrode are made of the same material in the same layer, and the second electrode and the fourth electrode are not connected.

In an exemplary embodiment of the present disclosure, the pixel spacer is disposed over the third electrode.

In an exemplary embodiment of the present disclosure, the touch unit further includes:

a first inorganic layer disposed over the second electrode;

a printing material layer disposed over the first inorganic layer;

a second inorganic layer disposed above the printing material layer and below the first electrode;

wherein the piezoelectric material layer is disposed over the first inorganic layer, and a projection of the piezoelectric material layer on the TFT backplane covers at least a projection of the second electrode on the TFT backplane.

In an exemplary embodiment of the present disclosure, a material of the piezoelectric material layer is organic.

According to a second aspect of the present disclosure, there is also provided a method for manufacturing a pressure-sensitive touch display panel, including:

manufacturing and forming a TFT backboard, wherein the TFT backboard is provided with a pixel area and a shielding area which are arranged at intervals;

forming an organic light emitting device in the pixel region;

forming a touch unit in the shielding area;

wherein forming the touch unit comprises:

forming a second electrode in the blocking region while forming a fourth electrode of the organic light emitting device in the pixel region;

forming a piezoelectric material layer on the second electrode;

a first electrode is formed on the layer of piezoelectric material.

In one exemplary embodiment of the present disclosure, forming the second electrode in the blocking region while forming the fourth electrode of the organic light emitting device in the pixel region includes:

and carrying out evaporation by adopting a high-precision metal mask plate, forming the fourth electrode in the pixel area, forming the second electrode in the shielding area, and disconnecting the second electrode from the fourth electrode.

According to a third aspect of the present disclosure, there is also provided a display device including the pressure-sensitive touch display panel described above.

According to the pressure-sensitive touch display panel, the preparation method thereof and the display device provided by some embodiments of the disclosure, on one hand, a touch unit is formed in a shielding area by using a plurality of packaging material layers for packaging an organic light-emitting device, and a piezoelectric material layer is arranged between two electrodes of the touch unit, so that a pressure sensor embedded in the touch display panel can be formed in the touch display panel, and the purpose of reducing the overall thickness of the display device is achieved; on the other hand, the touch screen can also play a role in detecting screen pressure and touch.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and together with the description, serve to explain the principles of the disclosure. It is to be understood that the drawings in the following description are merely exemplary of the disclosure, and that other drawings may be derived from those drawings by one of ordinary skill in the art without the exercise of inventive faculty.

Fig. 1 is a schematic diagram illustrating a pressure-sensitive touch display panel according to an exemplary embodiment of the disclosure.

Fig. 2A, 2B, and 2C are schematic diagrams illustrating a touch unit under the action of pressure or not in an exemplary embodiment of the disclosure.

Fig. 3 is a schematic diagram illustrating a specific detection and identification process of a touch unit in an example embodiment of the present disclosure.

Fig. 4 shows a flowchart of a method for manufacturing a pressure-sensitive touch display panel according to another exemplary embodiment of the disclosure.

Fig. 5 shows a cross-sectional view of a structure formed after an organic material evaporation process in another example embodiment of this example.

Fig. 6 shows a top view corresponding to fig. 5 in another example embodiment of the present example.

Fig. 7 shows a cross-sectional view of a structure formed after a metal evaporation process in another example embodiment of this example.

Fig. 8 shows a top view corresponding to fig. 7 in another example embodiment of the present example.

Fig. 9 shows a cross-sectional view of a structure formed after encapsulation by a first inorganic layer in another example embodiment of this example.

Fig. 10 shows a top view corresponding to fig. 9 in another example embodiment of the present disclosure.

FIG. 11 illustrates a cross-sectional view of a structure formed after fabrication of a layer of piezoelectric material in another example embodiment of the disclosure.

Fig. 12 shows a top view corresponding to fig. 11 in another example embodiment of the present disclosure.

Fig. 13 illustrates a cross-sectional view of a structure formed after fabricating a printing material layer and a second inorganic layer in another example embodiment of the disclosure.

Fig. 14 shows a top view corresponding to fig. 13 in another example embodiment of the present disclosure.

Fig. 15 illustrates a cross-sectional view of a structure formed after forming a first electrode in another example embodiment of the present disclosure.

Fig. 16 shows a top view corresponding to fig. 15 in another example embodiment of the present disclosure.

Detailed Description

Example embodiments will now be described more fully with reference to the accompanying drawings. Example embodiments may, however, be embodied in many different forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of example embodiments to those skilled in the art. The drawings are merely schematic illustrations of the present disclosure and are not necessarily drawn to scale. The same reference numerals in the drawings denote the same or similar parts, and thus their repetitive description will be omitted.

Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a thorough understanding of embodiments of the disclosure. One skilled in the relevant art will recognize, however, that the subject matter of the present disclosure can be practiced without one or more of the specific details, or with other methods, components, devices, steps, and the like. In other instances, well-known structures, methods, devices, implementations, materials, or operations are not shown or described in detail to avoid obscuring aspects of the disclosure.

Fig. 1 is a schematic diagram of a pressure-sensitive touch display panel provided in the present exemplary embodiment, and as shown in fig. 1, the pressure-sensitive touch display panel includes: a TFT backplane 110, an organic light emitting device 120, and a touch unit 130. The TFT backplane has a pixel region P1 and a shielding region P2, the organic light emitting device 120 is disposed on the TFT backplane and located in the pixel region P1, and the touch unit 130 is located in the shielding region P2. The organic light emitting device 120 is further provided with a plurality of encapsulating material layers for thin film encapsulation of the organic light emitting device.

The touch unit 130 includes: a first electrode, a second electrode and a layer of piezoelectric material disposed between the first electrode and the second electrode, wherein the second electrode is proximate to the TFT backplane 110.

Based on the above, in the present exemplary embodiment, the touch unit is formed in the shielding region by using the plurality of packaging material layers for packaging the organic light emitting device, and the piezoelectric material layer is disposed between the two electrodes of the touch unit, so that the pressure sensor embedded in the touch display panel can be formed in the touch display panel, and the purpose of reducing the overall thickness of the display device is achieved.

The pressure-sensitive touch display panel will be described in detail with reference to fig. 1 and specific examples as follows:

in the present exemplary embodiment, the TFT backplane 110 may include a substrate and a TFT array structure disposed on the substrate, such as a pixel driving circuit of an OLED. The pixel driving circuit includes a plurality of transistors, such as a Thin Film Transistor (TFT) and a storage capacitor. The TFT array structure may include a gate electrode, a gate insulating layer, an active layer, a source electrode, a drain electrode, a planarization layer, and other layers and structures on a conventional TFT array substrate, which are not described herein again.

In this exemplary embodiment, the pressure-sensitive touch display panel 100 further includes: and a pixel defining layer disposed on the TFT backplane 110, wherein the pixel defining layer includes pixel spacers 140 and openings W, which are spaced apart from each other, as shown in fig. 1, the pixel spacers 140 are located in the shielding region P2, the openings W are located in the pixel region P1, and the organic light emitting devices 120 are disposed at the openings W. The material of the pixel spacer 140 may be photoresist.

In the present exemplary embodiment, the organic light emitting device 120 includes a third electrode, a fourth electrode, and an organic functional layer disposed between the third electrode and the fourth electrode, wherein the organic functional layer may include, but is not limited to: a Hole Transport Layer (HTL), an Electron Blocking Layer (EBL), a light Emitting Layer (EL), an Electron Transport Layer (ETL), and the like. Each film layer of the organic light emitting device 120 may be formed by an evaporation process.

As shown in fig. 1, the organic light emitting device 120 disposed in the pixel region P1 includes the following layers in order: a third electrode 121, a hole transport layer 122, an electron blocking layer 123, a light emitting layer 124, an electron transport layer 125, and a fourth electrode 126. The third electrode 121 may be an anode of an organic light emitting device, and the material may be a transparent conductive oxide, such as Indium Tin Oxide (ITO), or a stacked structure of a transparent conductive oxide and a metal, such as ITO/Mg/ITO. The fourth electrode 126 may be a cathode of the organic light emitting device, and the material may be a metal, such as at least one of Ag and Mg.

The materials of the hole transport layer 122, the electron blocking layer 123, the light emitting layer 124 and the electron transport layer 125 of the organic light emitting device 120 can all adopt the materials and film thicknesses in the conventional OLED structure. It should be noted that the light emitting layers 124 in the sub-pixels with different colors are realized by doping different dopants into the main light emitter to realize blue (B), green (G) and red (R), and the thickness of one or more layers in the organic functional layer needs to be adjusted for the sub-pixels with different colors, which is not limited herein.

In this exemplary embodiment, the touch unit 130 disposed in the shielding region P2 includes the following film layers: a second electrode 131, a first inorganic layer 132, a piezoelectric material layer 133, a printing material layer 134, a second inorganic layer 135, and a first electrode 136. As shown in fig. 1, in which the first inorganic layer 132 is disposed over the second electrode 131, the piezoelectric material layer 133 is disposed over the first inorganic layer 132, and the piezoelectric material layer 133 is disposed only in the blocking region P2, the printing material layer 134 is disposed over the first inorganic layer 132 and completely covers over the piezoelectric material layer 133, and the second inorganic layer 135 is disposed over the printing material layer 134 and under the second electrode 136.

It should be noted that the projection of the piezoelectric material layer 133 of the touch unit 130 on the TFT backplane 110 at least covers the projection of the second electrode 131 on the TFT backplane 110, and therefore the projection of the piezoelectric material layer 133 on the TFT backplane 110 should be larger than the projection of the second electrode 131 on the TFT backplane 110. The material of the piezoelectric material layer 133 may be organic, i.e., an organic piezoelectric material, such as polyvinylidene fluoride.

The second electrode 131 of the touch unit 130 may be a sensing electrode (i.e., RX) of the touch unit 130, and the second electrode 131 and the fourth electrode 126 of the organic light emitting device 120 may be made of the same material in the same layer, so the material of the second electrode 131 may also be a metal, such as at least one of Ag and Mg. The first electrode 136 may be a driving electrode (i.e., TX) of the touch unit 130, and the material may be a metal material, such as Ti/Al/Ti or other metals. The second electrode 131 and the fourth electrode 126 are made of the same material in the same layer, but are disconnected from each other and are not connected to each other.

It should be noted that the positions of the sensing electrode and the driving electrode may be interchanged according to the design requirement, as long as when a touch pressure is applied to the screen from the outside, the cross position relationship between the driving electrode TX and the sensing electrode RX changes, which causes the change of the cross capacitance, and the capacitance of the driving electrode TX and the capacitance of the sensing electrode RX also change due to the external force squeezing or stretching the organic piezoelectric material between the driving electrode TX and the sensing electrode RX, which further achieves the effect of recognizing the touch and the pressure by detecting the signal change conditions of the driving electrode TX and the sensing electrode RX.

The first inorganic layer 132 and the second inorganic layer 134 of the touch unit 130 are made of inorganic materials, such as silicon oxide, silicon nitride, silicon oxynitride, and the like, and may be formed by CVD (Chemical Vapor Deposition) or the like, or may be formed by other methods, such as electroless plating, sputter Deposition, physical Vapor Deposition, and the like, and are not limited herein.

The material of the printing material layer 134 of the touch unit 130 may be organic, such as including but not limited to the following materials: at least one of materials such as epoxy-based resin, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), Polystyrene (PS), Polycarbonate (PC), Polyimide (PI), polyvinyl sulfonate, polyoxymethylene, polyarylate, acryl, and hexamethyldisiloxane.

Fig. 2A, 2B and 2C are schematic diagrams illustrating the touch unit 130 in this exemplary embodiment with or without pressure, as shown in fig. 2, a crystal is disposed between the upper and lower electrodes, and fig. 2A, 2B and 2C respectively illustrate changes generated to the piezoelectric material when no pressure is applied, when a tensile external force is applied, and when a compressive external force is applied. The principle of the touch unit 130 for pressure detection is as follows: when pressure acts on the piezoelectric material layer, polarization charges are generated on the upper surface and the lower surface of the material, the generated charge quantity is related to the force, and the arrangement structure of the crystals is changed under the action of external stretching force and external compression force.

Fig. 3 is a schematic diagram illustrating a specific detection and identification process of a touch unit, which includes the following steps:

firstly, after a driving electrode TX inputs a signal (such as a signal with a certain period), an induction electrode RX receives an output signal Vout signal, i.e., an F & T mixed signal (i.e., a pressure touch mixed signal), after having a pressure and touch effect; then, the F & T mixed signal is separated by a certain technical means to obtain a low-frequency force signal and a high-frequency touch signal, respectively, as shown in fig. 3, so as to obtain a pressure signal and a touch signal.

In the present exemplary embodiment, the pixel spacer 140 may be disposed on the third electrode 121, as shown in fig. 1, the third electrode 121 may be an electrode disposed on the TFT backplane 110 over an entire surface of the pixel region and the shielding region, and in addition, in other embodiments, the pixel spacer 140 may also be disposed on the TFT backplane 110, and the third electrode is disposed only on the stripe-shaped electrode in the pixel region. The selection can be performed according to the requirement in the actual application function, and the limitation is not performed.

Referring to the structure shown in fig. 1, in the multi-layer packaging material layer above the cathode of the organic light emitting device, the organic material and the inorganic material corresponding to the pixel region can be used for packaging the organic light emitting device, the inorganic material plays a role in blocking water and oxygen, the organic material plays a role in eliminating stress between the inorganic layers, and the like, meanwhile, the piezoelectric material layer can be arranged in the blocking region and forms a touch unit together with the first electrode and the second electrode, when external force is applied, polarization charges are generated on the upper surface and the lower surface of the piezoelectric material, the charge quantity is related to the force, and further the charge quantity of the first electrode and the second electrode is changed, so that the collected electric signals of the first electrode and the second electrode can be changed, and further the functions of detecting screen pressure and touch are achieved.

In summary, in the pressure-sensitive touch display panel provided in this exemplary embodiment, on one hand, the touch unit is formed in the shielding region by using the multiple layers of the packaging material layer for packaging the organic light emitting device, and the piezoelectric material layer is disposed between the two electrodes of the touch unit, so that the pressure sensor embedded in the touch display panel can be formed in the touch display panel, and the purpose of reducing the overall thickness of the display device is achieved; on the other hand, the touch screen can also play a role in detecting screen pressure and touch.

Fig. 4 illustrates a flowchart of a method for manufacturing a pressure-sensitive touch display panel according to some embodiments of the present disclosure, where the method for manufacturing a pressure-sensitive touch display panel may include the following steps:

as shown in fig. 4, in step S41, a TFT backplane is formed, wherein the TFT backplane has a pixel region and a shielding region disposed at an interval.

As shown in fig. 4, in step S42, an organic light emitting device is formed in the pixel region.

As shown in fig. 4, in step S43, a touch unit is formed in the shielding area.

Wherein the forming of the touch unit in step S43 includes:

forming a second electrode in the shielding region while forming a fourth electrode of the organic light emitting device in the pixel region; forming a piezoelectric material layer on the second electrode; and forming a first electrode on the piezoelectric material layer.

In step S43, forming the second electrode in the blocking region while forming the fourth electrode of the organic light emitting device in the pixel region includes:

and (3) carrying out evaporation by adopting a high-precision metal mask plate, forming a fourth electrode in the pixel area, forming a second electrode in the shielding area, and disconnecting the second electrode from the fourth electrode.

Still in step S43, the forming of the piezoelectric material layer on the second electrode includes:

forming a first inorganic layer on the second electrode;

the piezoelectric material layer is formed on the first inorganic layer by means of inkjet printing or through a patterning process.

According to the method for manufacturing the pressure-sensitive touch display panel shown in fig. 4, the touch unit is formed in the shielding area while the organic light emitting device is packaged, and the piezoelectric material layer is arranged between the two electrodes of the touch unit, so that the pressure sensor embedded in the touch display panel can be formed in the touch display panel, and the purpose of reducing the overall thickness of the display device is achieved.

Next, a method for manufacturing the pressure-sensitive touch display panel in the exemplary embodiment of fig. 4 will be described in detail.

In step S41, a TFT backplane is formed by the following steps: a gate electrode, a gate insulating layer, an active layer, a source electrode, a drain electrode, a planarization layer, etc. are formed on the substrate, which is the same as the conventional method and process for manufacturing the TFT array substrate and will not be described herein again.

In step S42, forming an organic light emitting device in the pixel region, specifically including:

and sequentially forming a third electrode, a Hole Transport Layer (HTL), an Electron Blocking Layer (EBL), a light-Emitting Layer (EL), an Electron Transport Layer (ETL) and the like on the TFT backboard by evaporation.

During or before the evaporation process of the organic light emitting device, a pixel defining layer is formed on the TFT backplane, the pixel defining layer includes pixel spacers and openings that are distributed at intervals, and the pixel spacers may be made of photoresist. The pixel spacer can be formed by evaporating a whole third electrode on the TFT backboard, and has a structure shown in FIG. 1; the organic light emitting device can also be formed after the TFT backboard is formed and before the third electrode is evaporated, namely, the pixel spacer is firstly manufactured and formed on the TFT backboard, and then the organic light emitting device is formed at the opening position by evaporation.

Specifically, the formation of the pixel spacer 140 on the TFT backplane or on the third electrode may be: and after coating the photoresist, exposing, developing and etching off part of the photoresist by using a mask plate to form a pixel spacer and a corresponding opening.

After the above steps, the third electrode 121, the Hole Transport Layer (HTL)122, the Electron Blocking Layer (EBL)123, the light Emitting Layer (EL)124, and the Electron Transport Layer (ETL)125 are sequentially formed at the gap on the TFT backplane 110 through an organic material evaporation process.

Fig. 5 shows a cross-sectional view of a structure formed after an organic material evaporation process, and fig. 6 shows a top view corresponding to fig. 5.

In fig. 6, the TFT backplane is not shown, and only the RGB sub-pixels with three different colors are shown. Fig. 5 and 6 are schematic diagrams, and do not show cross-sectional views and top views corresponding directly, fig. 5 shows only a cross-sectional view of one set of RGB (i.e., 3 columns of sub-pixels), and fig. 6 shows a top view of two sets of RGB (i.e., 6 columns of sub-pixels).

After the organic evaporation process, cathode Metal evaporation is performed on the Electron Transport Layer (ETL)125 by using FMM (Fine Metal Mask), a fourth electrode 126 (i.e., a cathode) is formed in the pixel region, and a second electrode 131 (i.e., an induction electrode RX of the touch unit) is formed in the shielding region. The second electrode 131 is not connected to the fourth electrode 126, and the second electrode 131 is formed on the pixel spacer 140. The cathode metal may be Mg/Ag, and in addition, since there is a difference in film thickness of the organic material in the pixel regions of different colors, there is a corresponding difference in height of the fourth electrode 126 formed, but the second electrode is the same height since it is formed on the pixel spacer 140.

In addition to the above-mentioned forming by using FMM mask, the process of forming the second electrode 131 and the fourth electrode 126 may also be a process of controlling OLED cathode patterning in the pixel definition layer, which specifically includes: since there is a gap or a difference in height between the pixel spacer and the organic functional layer formed by vapor deposition, the second electrode 131 and the fourth electrode 126 are also disconnected when a metal layer is formed by vapor deposition, or the like on the structure having different heights as shown in fig. 5.

Fig. 7 shows a cross-sectional view of a structure formed after a metal evaporation process, and fig. 8 shows a top view corresponding to fig. 7, that is, a second electrode 131 and a fourth electrode 126 are formed without connection.

In step S43, the organic light emitting device is film-packaged, and a touch unit is formed in the shielding region by using the plurality of packaging material layers for film-packaging.

First, a first layer of encapsulation, i.e., encapsulation of the first inorganic layer 132, is performed, and the first inorganic layer 132 is formed through a deposition process, wherein the first inorganic layer 132 completely covers the second electrode 131 and the fourth electrode 126.

Fig. 9 shows a cross-sectional view of the structure formed after encapsulation by the first inorganic layer, and fig. 10 shows a top view corresponding to fig. 9.

Next, a piezoelectric material layer 133 is formed on the first inorganic layer by an inkjet printing method or a patterning process, and the material may be an organic piezoelectric material, such as polyvinylidene fluoride. And the projection of the piezoelectric material layer 133 on the TFT backplane 110 covers at least the projection of the second electrode 131 on the TFT backplane 110.

Fig. 11 shows a cross-sectional view of a structure formed after the piezoelectric material layer is fabricated, and fig. 12 shows a top view corresponding to fig. 11.

Then, a printing material layer 134 is formed on the piezoelectric material layer 133 and on the first inorganic layer 132 uncovered by the piezoelectric material layer 133 by means of inkjet printing, and the encapsulation is continued, that is, the encapsulation of the second inorganic layer 135, and the second inorganic layer 135 is formed through a deposition process. The material in which the layer of printing material is printed may be organic, such as including but not limited to the following materials: at least one of materials such as epoxy-based resin, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), Polystyrene (PS), Polycarbonate (PC), Polyimide (PI), polyvinyl sulfonate, polyoxymethylene, polyarylate, acryl, and hexamethyldisiloxane.

The first inorganic layer 132 and the second inorganic layer 135 deposited in the above steps can be formed by CVD (Chemical Vapor Deposition), electroless plating, sputtering Deposition, physical Vapor Deposition, and the like, and are not limited herein. The material of the first inorganic layer 132 and the second inorganic layer 135 may be silicon oxide, silicon nitride, silicon oxynitride, or the like.

Fig. 13 shows a cross-sectional view of a structure formed after the printing material layer and the second inorganic layer are fabricated, and fig. 14 shows a top view corresponding to fig. 13.

Finally, a metal layer is deposited on the second inorganic layer 135, and a first electrode 136, i.e., a driving electrode TX of the touch unit, is formed through a patterning process. The material of the driving electrode TX may be a metal material, such as Ti/Al/Ti or other metals.

Fig. 15 shows a cross-sectional view of a structure formed after forming the first electrode, fig. 16 shows a top view corresponding to fig. 15, and fig. 16 also shows a positional relationship between the first electrode and the second electrode in the touch unit, that is, the first electrode crosses the second electrode and overlaps with a projection of the piezoelectric material layer 134, so that only the piezoelectric material layer and the first electrode can be displayed as the uppermost layer in fig. 16.

It should be noted that, in the present exemplary embodiment, the above description of the thickness of each film layer is only a reference value, and does not mean that the thickness of each film layer is limited to the reference value, and in an actual process and a product manufacturing, a reasonable range of the thickness of each film layer may be selected according to needs, and is not limited herein.

It is further noted that the patterning process in the present exemplary embodiment generally includes processes of photoresist coating, exposure, development, etching, photoresist stripping, and the like. The corresponding patterning process may be selected in accordance with the structures formed in the present disclosure during actual processing.

In summary, in the OLED packaging process, while the cathode of the organic light emitting device is manufactured in the pixel area, the sensing electrode of the touch unit is formed on the pixel spacer in the shielding area, and the piezoelectric material layer is further disposed between the driving electrode and the sensing electrode in the touch unit, so that the pressure sensing and the touch are simultaneously completed in the OLED packaging process, and the pressure sensor embedded in the touch display panel is formed in the touch display panel, so as to achieve the purpose of reducing the overall thickness of the display device; the touch screen can also play a role in detecting screen pressure and touch.

Based on the above, the present disclosure further provides, in another exemplary embodiment, a display device, which includes the pressure-sensitive touch display panel.

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

In addition, the display device can achieve the same effect as the pressure-sensitive touch display panel, and the description is omitted here.

It should be clearly understood that this disclosure describes how to make and use particular examples, but the principles of this disclosure are not limited to any details of these examples. Rather, these principles can be applied to many other embodiments based on the teachings of the present disclosure.

Exemplary embodiments of the present disclosure are specifically illustrated and described above. It is to be understood that the present disclosure is not limited to the precise arrangements, instrumentalities, or instrumentalities described herein; on the contrary, the disclosure is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims

1. A pressure sensitive touch display panel, comprising:

the organic light-emitting device is arranged on the TFT backboard and is positioned in the pixel area; the organic light-emitting device comprises a third electrode and a fourth electrode which are arranged on the TFT backboard, and an organic functional layer arranged between the third electrode and the fourth electrode;

the touch control unit is positioned in the shielding area; the touch unit comprises a first electrode, a second electrode close to the TFT backboard and a piezoelectric material layer arranged between the first electrode and the second electrode;

a multi-layered encapsulation material layer for thin film encapsulation of the organic light emitting device, the multi-layered encapsulation material layer including a first inorganic layer disposed over the second electrode, a printing material layer disposed over the first inorganic layer, a second inorganic layer disposed over the printing material layer and under the first electrode;

the second electrode and the fourth electrode are made of the same material in the same layer, and the second electrode is not connected with the fourth electrode; the piezoelectric material layer is only arranged in the shielding area and on the first inorganic layer, the projection of the piezoelectric material layer on the TFT backboard at least covers the projection of the second electrode on the TFT backboard, and the printing material layer completely covers the piezoelectric material layer.

2. The pressure-sensitive touch display panel according to claim 1, further comprising:

a pixel defining layer disposed on the TFT backplane;

3. The pressure-sensitive touch display panel of claim 2, wherein the pixel spacer is disposed over the third electrode.

4. The pressure-sensitive touch display panel according to claim 1, wherein the piezoelectric material layer is made of organic material.

5. A preparation method of a pressure-sensitive touch display panel is characterized by comprising the following steps:

forming an organic light emitting device in the pixel region; the organic light-emitting device comprises a third electrode and a fourth electrode which are arranged on the TFT backboard, and an organic functional layer arranged between the third electrode and the fourth electrode;

forming a plurality of packaging material layers for performing thin film packaging on the organic light-emitting device, and forming a touch unit in the shielding area by using the plurality of packaging material layers for performing thin film packaging; the touch unit comprises a first electrode, a second electrode close to the TFT backboard and a piezoelectric material layer arranged between the first electrode and the second electrode; the multilayer packaging material layer comprises a first inorganic layer disposed over the second electrode, a printing material layer disposed over the first inorganic layer, a second inorganic layer disposed over the printing material layer and under the first electrode;

6. A display device comprising the pressure-sensitive touch display panel according to any one of claims 1 to 4.