CN109873085B

CN109873085B - Bottom-emission white-light organic light-emitting diode display panel, manufacturing method thereof and display device

Info

Publication number: CN109873085B
Application number: CN201910144112.7A
Authority: CN
Inventors: 吴元均; 袁伟; 矫士博
Original assignee: Shenzhen China Star Optoelectronics Semiconductor Display Technology Co Ltd
Current assignee: Shenzhen China Star Optoelectronics Semiconductor Display Technology Co Ltd
Priority date: 2019-02-27
Filing date: 2019-02-27
Publication date: 2020-11-10
Anticipated expiration: 2039-02-27
Also published as: WO2020172945A1; CN109873085A

Abstract

A bottom-emission white-light organic light-emitting diode display panel and a manufacturing method and a display device thereof are provided, wherein the bottom-emission WOLED display panel comprises a substrate, a thin film transistor, a WOLED color film layer, a quantum dot light-induced conversion layer, a first electrode, a WOLED electroluminescence function layer and a second electrode. The WOLED color film layer is sequentially provided with red, green, blue and white pixels. The quantum dot photoconversion layer comprises quantum dot red-green luminous materials which are arranged corresponding to the red-green pixels. A WOLED electroluminescent functional layer is disposed on the first electrode. The second electrode is arranged on the WOLED electroluminescent functional layer, and blue light or yellow light of the WOLED electroluminescent functional layer is converted into red light and green light through the quantum dot red-green luminescent material of the quantum dot photoluminescence layer, so that the brightness of the red pixel and the green pixel is improved, and the color gamut expression of the bottom emission WOLED display panel is improved.

Description

Bottom-emission white-light organic light-emitting diode display panel, manufacturing method thereof and display device

Technical Field

The invention relates to the technical field of display, in particular to a bottom emission White Organic Light Emitting Diode (WOLED) display panel, a manufacturing method thereof and a display device.

Background

Compared with the LCD display technology, the Organic Light Emitting Diode (OLED) has the characteristics of active light emission, real color, infinite contrast, zero delay, transparent display, flexible display, Free-Form D (insulated shielding display) and the like, and is the next generation display technology capable of replacing the liquid crystal display technology. The OLED display technology does not need a backlight source, so that the structure is simpler than that of an LCD, and the volume of a display product can be thinner and thinner. The main application in the large-size panel display technology is White Organic Light Emitting Diode (WOLED), which is different from the wide application in the small-size side-by-side RGB technology, and the greatest advantage is that a Fine Metal Mask (FMM) is not required in the manufacturing process, so the equipment cost can be greatly reduced.

However, the conventional WOLED mainly uses a two-layer or three-layer structure of blue + yellow (BY) or blue + red + green (BGR) to realize white light. Due to the wide spectrum of white light, when the white light is separated into RGB three primary colors by using a Color Filter (CF), the RG spectrum is generally wide, the color purity is low, and the color gamut performance of the panel is difficult to break through the 100% standard established by NTSC (national television standards committee). In addition, when white light is separated into RG spectrum, only less red or green light part of the white light spectrum can be utilized, and the energy loss of the blue and yellow light parts is larger. Therefore, the existing WOLED has the problem of high power consumption when the panel works due to low energy utilization rate.

Disclosure of Invention

The invention provides a bottom emission White Organic Light Emitting Diode (WOLED) display panel, a manufacturing method thereof and a display device.

To achieve the above-mentioned objective, the present invention provides a bottom emission White Organic Light Emitting Diode (WOLED) display panel, which includes a substrate, a thin film transistor, a WOLED color film layer (WOLED-CF), a quantum dot photoconversion layer, a first electrode, a WOLED electroluminescent functional layer, and a second electrode. The thin film transistor is arranged on the substrate, and a first protective layer is arranged on the thin film transistor to protect the inner structure of the thin film transistor. A WOLED color film layer (WOLED-CF) is disposed on the first protective layer, the WOLED color film layer sequentially having red, green, blue, and white (RGBW) pixels and a second protective layer disposed on the WOLED color film layer. And the quantum dot photoconversion layer is arranged on the second protective layer. The quantum dot photoconversion layer includes quantum dot red-green (QD-R & G) luminescent materials disposed corresponding to the red-green (RG) pixels, and a resin layer or a flat layer is disposed on the quantum dot photoconversion layer. The first electrode is disposed on the resin layer or the planarization layer thin film transistor, and a red, green, blue, and white (RGBW) pixel region is defined on the first electrode. The WOLED electroluminescence function layer is arranged on the first electrode and corresponds to the quantum dot photoluminescence layer. A second electrode is disposed on the WOLED electroluminescent functional layer, wherein blue or yellow light of the WOLED electroluminescent functional layer is converted into red and green light by the quantum dot red-green (QD-R & G) luminescent material of the quantum dot photoconversion layer, thereby enhancing the luminance of the red and green pixels.

According to an embodiment of the invention, the red and green (QD-R & G) luminescent materials of the quantum dots are disposed corresponding to the Red and Green (RG) pixels of the WOLED color film, and the Blue and White (BW) pixels of the WOLED color film are blank corresponding to the quantum dot photoconversion layer, wherein the quantum dot photoconversion layer is a quantum dot enhanced film (QD-EF).

According to an embodiment of the present invention, the WOLED electroluminescent functional layer includes any combination of blue light + yellow light, blue light + red light + yellow light, or blue light + red light + green light, and the WOLED electroluminescent functional layer includes 2 or 3 stacked layers and is an upright or inverted structure.

According to an embodiment of the present invention, the WOLED electroluminescent functional layer includes a hole injection layer (HIL: HATCN), a hole transport layer (HTL: NPB), a blue emission layer (B-EML: FIrpic), a charge transport layer (TPBi), a charge generation layer (BPhen: Li), a hole generation layer (HATCN), a yellow emission layer (Y-EML: PO-48), and a charge injection layer (Liq).

According to an embodiment of the present invention, the thin film transistor further includes a gate electrode, a gate insulating layer stacked on the gate electrode, an active layer, an insulating shielding layer, and a source/drain electrode, the first protective layer is disposed on the source/drain electrode, and is a resin material, and the thin film transistor is a Bottom Gate (BG) TFT structure.

According to an embodiment of the present invention, the thin film transistor further includes a shielding layer, a buffer layer, an active layer, a gate insulating layer, a gate electrode, an interlayer insulating layer, and a source drain electrode, which are disposed on the substrate, the first protective layer is disposed on the interlayer insulating layer and uses silicon oxide (SiOx) as a passivation layer, and the thin film transistor is a Dual Gate (DG) TFT structure.

According to an embodiment of the present invention, a blank layer or a pixel defining layer is further disposed on the first electrode, and the blank layer or the pixel defining layer is adjacent to the WOLED electroluminescent functional layer.

The present invention also provides a display device including the bottom emission White Organic Light Emitting Diode (WOLED) display panel as in the above embodiment, and a polarizing layer disposed on the other side of the substrate.

Furthermore, the invention also provides a manufacturing method of the bottom emission White Organic Light Emitting Diode (WOLED) display panel, which comprises the following steps:

s10, providing a substrate;

s20, manufacturing and forming the thin film transistor on a substrate, and forming a first protective layer on the thin film transistor;

s30, forming a WOLED color film layer (WOLED-CF) on the first protection layer, wherein the WOLED color film layer sequentially forms red, green, blue and white (RGBW) pixels and forms a second protection layer on the WOLED color film layer;

s40, forming a quantum dot photoconversion layer (QD-PL conversion layer) on the second protective layer, the quantum dot photoconversion layer including quantum dot red green and green (QD-R & G) luminescent materials filled corresponding to the Red and Green (RG) pixels, and forming a resin layer or a planarization layer on the quantum dot photoconversion layer;

s50, forming a first electrode on the resin layer or the planarization layer, and defining a red, green, blue and white (RGBW) pixel region on the first electrode;

s60, forming a WOLED electroluminescence function layer on the first electrode and corresponding to the quantum dot light-induced conversion layer; and

s70, forming a second electrode on the WOLED electroluminescent functional layer, wherein blue or yellow light of the WOLED electroluminescent functional layer is converted into red and green light by the quantum dot red-green (QD-R & G) luminescent material of the quantum dot photoconversion layer, thereby enhancing the brightness of the red and green pixels.

According to an embodiment of the present invention, in step S40, the quantum dot photoconversion layer is manufactured by inkjet printing, nozzle printing or transfer molding, and fills a quantum dot red green and green (QD-R & G) luminescent material in a corresponding Red and Green (RG) pixel region, the quantum dot red and green luminescent material is not filled in a Blue and White (BW) pixel region, and the quantum dot photoconversion layer is a quantum dot enhanced film and has a thickness of 10 to 200 nanometers (nm).

According to an embodiment of the invention, in step S60, the WOLED electroluminescent functional layer includes any combination of blue light + yellow light, blue light + red light + yellow light + green light, or blue light + red light + green light.

According to an embodiment of the present invention, after step S60, a blank layer or a pixel defining layer is further formed on the first electrode, the blank layer or the pixel defining layer is adjacent to the WOLED electroluminescent functional layer and defines the red, green, blue and white (RGBW) pixel region.

According to an embodiment of the present invention, step S30 includes coating a resin material or depositing silicon oxide on the thin film transistor and forming a pattern by developing and exposing to form the first protection layer.

According to an embodiment of the present invention, after step S70, the method further includes covering a Cover Glass (CG) disposed over the second electrode, and an encapsulation material attached to and encapsulating the substrate and the CG, wherein the encapsulation material is selected from a group consisting of a dam encapsulation, a dam-in encapsulation, a frit encapsulation, a surface-sealing encapsulation, and a film encapsulation.

The invention also has the following beneficial effects: according to the invention, a quantum dot photoconversion layer is added between the WOLED electroluminescence functional layer and the WOLED color film layer, wherein the quantum dot photoconversion layer contains an organic material matrix, and the characteristics of WOLED transparent display, flexible display, free display form and the like are not influenced. The quantum dot photoluminescence layer can convert blue light of a short wavelength part in the WOLED electroluminescence function layer into red light or green light by utilizing photoluminescence characteristics of the quantum dot luminescent material, so that the energy utilization efficiency of the display panel on the WOLED electroluminescence function layer is increased, the color gamut expression of the display panel is improved, and the power consumption of the display panel is reduced.

Drawings

In order to illustrate the embodiments or the technical solutions in the prior art more clearly, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the invention, and it is obvious for a person skilled in the art that other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a schematic cross-sectional view of a bottom emitting White Organic Light Emitting Diode (WOLED) display panel;

FIG. 2 is another cross-sectional schematic view of a bottom emission White Organic Light Emitting Diode (WOLED) display panel in accordance with the present invention; and

FIG. 3 is a block diagram of a method for fabricating a bottom emission White Organic Light Emitting Diode (WOLED) display panel according to the present invention.

Detailed Description

Reference in the detailed description to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the invention. The appearances of the same phrases in various places in the specification are not necessarily limited to the same embodiment, but are to be construed as independent or alternative embodiments to other embodiments. In light of the disclosure of the embodiments provided by the present invention, it should be understood by those skilled in the art that the embodiments described in the present invention can have other combinations or variations consistent with the concept of the present invention.

The following description of the embodiments refers to the accompanying drawings for illustrating the specific embodiments in which the invention may be practiced. Directional phrases referred to herein, such as [ upper ], [ lower ], [ front ], [ rear ], [ left ], [ right ], [ inner ], [ outer ], [ side ], [ vertical ], [ horizontal ], etc., refer only to the directions of the attached drawings. Accordingly, the directional terms used are used for explanation and understanding of the present invention, and are not used for limiting the present invention. In the drawings, elements having similar structures are denoted by the same reference numerals.

Fig. 1 is a schematic view of a first preferred embodiment of the present invention. The invention provides a bottom emission White Organic Light Emitting Diode (WOLED) display panel, which comprises a substrate 1, a thin film transistor 2, a WOLED color film layer (WOLED-CF)3, a quantum dot light-induced conversion layer 4, a first electrode 5, a WOLED electroluminescence functional layer 6 and a second electrode 7. The substrate 1 includes, but is not limited to, a rigid substrate, a flexible substrate, such as a glass substrate, a polyimide substrate, or other suitable substrates.

The thin film transistor 2 is disposed on the substrate 1, and a first protective layer 11 is disposed on the thin film transistor 2 to protect the internal structure of the thin film transistor 2. A WOLED color film layer 3(WOLED-CF) is disposed on the first protective layer 11, the WOLED color film layer 3 sequentially having red, green, blue, and white (RGBW) pixels and a second protective layer 12 disposed on the WOLED color film layer 3. A quantum dot photoconversion layer 4(QD-PL conversion layer) is disposed on the second protective layer 12.

The quantum dot photoconversion layer 4 includes quantum dot red-green (QD-R & G) luminescent materials disposed corresponding to the red-green (RG) pixels, and a resin layer or planarization layer 13 is disposed on the quantum dot photoconversion layer 4. The first electrode 5 is disposed on the resin layer or the planarization layer 13, and defines a red, green, blue, and white (RGBW) pixel region on the first electrode 5. The WOLED electroluminescence functional layer 6 is arranged on the first electrode 5 and corresponds to the quantum dot light-induced conversion layer 4. The second electrode 7 is disposed on the WOLED electroluminescent functional layer 6, wherein blue light or yellow light of the WOLED electroluminescent functional layer 6 is converted into red light and green light by the quantum dot red-green (QD-R & G) luminescent material (not shown) of the quantum dot photoconversion layer 4, so as to improve the brightness of the red pixel and the green pixel, thereby improving the color gamut performance of the bottom emission WOLED display panel.

The quantum dot photoconversion layer 4 includes the quantum dot red-green (QD-R & G) luminescent materials corresponding to the red-green (RG) pixel arrangement of the WOLED color film layer 3, while the blue-white (BW) pixels of the WOLED color film layer 3 corresponding to the quantum dot photoconversion layer 4 are blank, i.e., the quantum dot red-green luminescent materials are not filled in the blue-white pixel area. The Quantum Dot photoconversion layer 4 of the present embodiment is preferably a Quantum Dot enhanced Film (QD-EF). Therefore, the present invention utilizes the photoluminescence characteristics of the quantum dot red-green (QD-R & G) luminescent material in the quantum dot photoconversion layer 4 to convert the blue-white light in the WOLED electroluminescence functional layer 6 into red light or green light, so as to enhance the energy utilization efficiency of the display panel to the WOLED electroluminescence functional layer 6, simultaneously improve the color gamut performance of the display panel, and reduce the power consumption of the display panel.

The WOLED electroluminescent functional layer 6 comprises any combination of blue light + yellow light, blue light + red light + yellow light + green light or blue light + red light + green light. The WOLED electroluminescent functional layer 6 comprises 2stacks (2stacks), 3stacks (3stacks) or other multi-stack structures, and may be an upright or inverted structure, all as desired.

The WOLED electroluminescent functional layer 6 further includes a hole injection layer (HIL: HATCN), a hole transport layer (HTL: NPB), a blue light emitting layer (B-EML: FIrpic), a charge transport layer (TPBi), a charge generation layer (BPhen: Li), a hole generation layer (HATCN), a yellow light emitting layer (Y-EML: PO-48), and a charge injection layer (Liq).

In the embodiment shown in fig. 1, a protective glass 8(CG) covering the second electrode 7 and an encapsulation material 10(encapsulation material) adhering to and encapsulating the substrate 1 and the protective glass 8 are further included. The encapsulating material 10 is perpendicular to the WOLED electroluminescent functional layer 6, the quantum dot photoconversion layer 4 and the cover glass 8.

The thin film transistor 2 further includes a gate electrode 21 disposed on the substrate 1, a gate insulating layer 22 stacked on the gate electrode 21, an active layer 23, an insulating shielding layer 24, and a source/drain electrode 25. The first protective layer 11 is disposed on the source/drain electrode 25, and the first protective layer 11 is preferably a resin layer, so as to protect each layer of the thin film transistor 2. The first electrode 5 is disposed on the resin layer and electrically connected to the source/drain 25. The thin film transistor 2 shown in fig. 1 is, for example, a Bottom Gate (BG) TFT structure.

Fig. 2 is a schematic diagram illustrating a second embodiment of the present invention. The difference between this embodiment and the above embodiments is that the thin film transistor 2' is, for example, a Double Gate (DG) TFT structure. Specifically, the thin film transistor 2 'further includes a shielding layer 21' provided on the substrate 1, a buffer layer 22 'stacked on the shielding layer 21', an active layer 23 ', a gate insulating layer 24', a gate 25 ', an interlayer insulating layer 26', and a source/drain 27. The first protective layer 11 is disposed on the interlayer insulating layer 24 'and uses silicon oxide (SiOx) as a passivation layer, thereby protecting each layer of the thin film transistor 2'. The first electrode 3 is disposed on the passivation layer and electrically connected to the source/drain electrode 25'.

In the first and second embodiments, a blank layer 14 (fig. 1) or a pixel defining layer 14 (fig. 2) is further provided on the first electrode 5. The blank layer 14 or the pixel defining layer 14 adjoins the WOLED electroluminescent functional layer 6.

The present invention also provides a display device, which includes a polarizing layer 9(polarizing layer) disposed on the other side of the substrate 1, and the bottom emission White Organic Light Emitting Diode (WOLED) display panel as in the above embodiments. The polarizing layer 9 can realize high brightness and high contrast. For the related structure of the display device, please refer to the above embodiments, which are not described herein again.

Fig. 3 is a block diagram of a method for manufacturing a bottom emission White Organic Light Emitting Diode (WOLED) display panel according to the present invention. As shown in the drawings, the present invention also provides a method for manufacturing a bottom emission White Organic Light Emitting Diode (WOLED) display panel, comprising the steps of: s10, providing a substrate 1; s20, forming the thin film transistors 2 and 2 'on the substrate 1, and forming the first protective layer 11 on the thin film transistors 2 and 2'; s30, forming a WOLED color film layer 3(WOLED-CF) on the first protection layer 11, the WOLED color film layer 3 sequentially forming red, green, blue and white (RGBW) pixels and forming a second protection layer 12 on the WOLED color film layer 3; s40, forming a quantum dot photoconversion layer 4(QD-PL conversion layer) on the second protective layer 12, wherein the quantum dot photoconversion layer 4 includes a quantum dot red-green (QD-R & G) luminescent material filled corresponding to the red-green (RG) pixels, and forming a resin layer or a planarization layer 13 on the quantum dot photoconversion layer 4; s50, forming a first electrode 5 on the resin layer or the planarization layer 13, and defining a red, green, blue and white (RGBW) pixel region on the first electrode 5; s60, forming a WOLED electroluminescence functional layer 6 on the first electrode 5 and arranging the WOLED electroluminescence functional layer corresponding to the quantum dot light-induced conversion layer 4; and S70, forming a second electrode 7 on the WOLED electroluminescent functional layer 6, wherein blue or yellow light of the WOLED electroluminescent functional layer 6 is converted into red and green light by the quantum dot red-green (QD-R & G) luminescent material of the quantum dot photoconversion layer 4, thereby increasing the brightness of the red and green light and reducing the power consumption of the display panel.

After step S60, a blank layer 14 or a pixel defining layer 14 is also formed on the first electrode 5. The blank layer 14 or the pixel defining layer 14 adjoins the WOLED electroluminescent functional layer 6. In step S60, the WOLED electroluminescent functional layer 6 contains any combination of blue light + yellow light, blue light + red light + yellow light + green light, or blue light + red light + green light. The WOLED electroluminescent functional layer 6 can comprise a 2-layer stack, a 3-layer stack or a multi-layer stack structure, and is in an upside-down or upside-down configuration, which may be changed as required.

In step S70, the second electrode 7 is made of a material such as Ag and has a thickness of 100-200 nm (nm). The second electrode 5 has good light transmittance in the visible light region.

In step S40, the quantum dot photoconversion layer 4 is formed by inkjet printing (ink-jet printing), nozzle printing (nozzle printing) or transfer molding (transfer) process. The quantum dot photoconversion layer 4 further fills quantum dot red green (QD-R & G) luminescent materials (not shown) in corresponding Red Green (RG) pixel regions, and the quantum dot red green luminescent materials are not filled in Blue White (BW) pixel regions, that is, the quantum dot red green luminescent materials corresponding to the Blue White (BW) pixel regions are blank (blank). The Quantum Dot photoconversion layer 4 of the present embodiment is preferably a Quantum Dot Enhancement Film (QD-EF) with a thickness of 10-200 nanometers (nm).

After step S70, a cover glass 8(CG) covering over the second electrode 7 and an encapsulation material 10(encapsulation material) adhering and encapsulating the substrate 1 and the cover glass 8 are further included. The sealing material 10 bonds and seals the substrate 1 and the cover glass 8 through a process such as a Dam package (Dam package), a Dam & Fill package (Dam & Fill package), a Frit package (Frit package), a Face-seal package (Face-seal package), or a thin film package (TFE).

In an embodiment of step S20 (fig. 1), the tft 2 is fabricated by depositing an Al/Mo metal layer on the substrate 1 in sequence, and patterning the metal layer through exposure, development, etching, stripping (strip), and the like to form the gate electrode 21. SiOX is deposited on the gate electrode 21 as a gate insulating layer 22(insulating gate layer) of the gate electrode 21. An IGZO layer (Indium Gallium Zinc Oxide) is deposited on the gate insulating layer 22, and the IGZO layer is patterned by exposure, development, etching, film stripping, and the like to form an active layer 23. SiOx is deposited on the active layer 23, and patterned by exposure, development, etching, film stripping, etc., to form an insulating shielding layer 24 and protect the active layer 23. And sequentially depositing a Mo/Al/Mo metal layer on the insulating shielding layer 24, and patterning the Mo/Al/Mo metal layer through the processes of exposure, development, etching, film stripping and the like to form a source drain 25. The source/drain 25 is coated with a resin, and the resin is patterned by exposure, development, and the like to form the first protective layer 11 of the resin layer and to protect each layer from passivation.

In another embodiment (fig. 2) of step S20, a Mo metal layer is sequentially deposited on the substrate 1, and patterned through exposure, development, etching, film stripping, and the like to form a shielding layer 15(shielding layer). SiOX is deposited on the shielding layer 15 as a buffer layer 16. IGZO is deposited on the buffer layer 16, and the IGZO layer is patterned through processes such as exposure, development, etching, and stripping to form an active layer 21'. SiOX is deposited over the active layer 21 ', forming a gate insulating layer 22 ' and protecting the active layer 21 '. A Mo/Al/Mo metal layer is sequentially deposited on the gate insulating layer 22 ', and patterned by exposure, development, etching, stripping, and the like to form a gate 23'. SiOX is deposited on the gate 23 ' as an interlayer insulating layer 24 ', and the interlayer insulating layer 24 ' and the buffer layer 16 are patterned by exposure, development, etching, stripping, and the like. A Mo/Al/Mo metal layer is deposited on the interlayer insulating layer 24 ', and the metal layer is patterned by exposure, development, etching, film stripping, and the like to form a source/drain 25' and a capacitor. SiOX is deposited on the source/drain 25 'as the first protective layer 11 (i.e., passivation layer), and then the passivation layer is patterned by exposure, development, etching, stripping, and the like to protect the source/drain 25'.

Therefore, the invention can convert the blue light of the short wavelength part in the WOLED electroluminescent functional layer 5 into red light or green light by the photoluminescence characteristic of the quantum dot luminescent material through the quantum dot photoluminescence layer 4, so as to increase the energy utilization efficiency of the display panel to the WOLED electroluminescent functional layer 5, improve the color gamut expression of the display panel and reduce the power consumption of the display panel.

In summary, although the present invention has been disclosed with reference to the preferred embodiments, the above-mentioned preferred embodiments are not intended to limit the present invention, and those skilled in the art will appreciate that various modifications and changes can be made without departing from the spirit and scope of the present invention, which is defined by the appended claims.

Claims

1. A bottom emission white organic light emitting diode display panel comprising:

a substrate;

the thin film transistor is arranged on the substrate, and a first protective layer is arranged on the thin film transistor to protect the inner structure of the thin film transistor;

the WOLED color film layer is arranged on the first protection layer, red, green, blue and white pixels are sequentially arranged on the WOLED color film layer, and a second protection layer is arranged on the WOLED color film layer;

a quantum dot photoconversion layer arranged on the second protective layer, wherein the quantum dot photoconversion layer comprises quantum dot red-green luminous materials arranged corresponding to the red-green pixels, and a resin layer or a flat layer is arranged on the quantum dot photoconversion layer;

a first electrode disposed on the resin layer or the planarization layer and defining a red, green, blue, and white pixel region on the first electrode;

the WOLED electroluminescence functional layer is arranged on the first electrode and corresponds to the quantum dot light-induced conversion layer; and

and the second electrode is arranged on the WOLED electroluminescence functional layer, wherein the blue light or the yellow light of the WOLED electroluminescence functional layer is converted into red light and green light through the quantum dot red-green light emitting material of the quantum dot photoluminescence layer, so that the brightness of the red pixel and the green pixel is improved.

2. The bottom-emitting white-light organic light emitting diode display panel of claim 1, wherein the quantum dot red-green emitting material is disposed corresponding to the red-green pixels of the WOLED color film layer, and the blue-white pixels of the WOLED color film layer are blank corresponding to the quantum dot light-induced conversion layer, wherein the quantum dot light-induced conversion layer is a quantum dot enhanced thin film.

3. The bottom-emission white-light organic light emitting diode display panel of claim 1, wherein the WOLED electroluminescent functional layer comprises any one combination of blue light + yellow light, blue light + red light + yellow light + green light, or blue light + red light + green light, and the WOLED electroluminescent functional layer comprises a 2-layer or 3-layer stacked structure and is an upside-down or upside-down structure.

4. The bottom-emission white-light organic light emitting diode display panel of claim 1, wherein the WOLED electroluminescent functional layer comprises a hole injection layer, a hole transport layer, a blue light emitting layer, a charge transport layer, a charge generation layer, a hole generation layer, a yellow light emitting layer, and a charge injection layer.

5. The bottom-emission white-light organic light emitting diode display panel of claim 1, further comprising a cover glass and a packaging material, wherein the cover glass covers over the second electrode, the packaging material is attached to and encapsulates the substrate and the cover glass, the packaging material is perpendicular to the WOLED electroluminescent functional layer, the quantum dot photoconversion layer and the cover glass, the thin film transistor further comprises a gate electrode, a gate insulating layer stacked on the gate electrode, an active layer, an insulating shielding layer and a source drain electrode, the first protective layer is disposed on the source drain electrode, wherein the first protective layer is a resin material, and the thin film transistor is a bottom-gate TFT structure.

6. The bottom-emission white-light organic light emitting diode display panel of claim 1, wherein the thin film transistor further comprises a shielding layer, a buffer layer, an active layer, a gate insulating layer, a gate electrode, an interlayer insulating layer, and source and drain electrodes disposed on the substrate, wherein the first protective layer is disposed on the interlayer insulating layer and has silicon oxide as a passivation layer, and the thin film transistor has a dual gate TFT structure.

7. The bottom-emitting white-light organic light emitting diode display panel of claim 1, wherein a blank layer or a pixel definition layer is further disposed on the first electrode, the blank layer or the pixel definition layer abutting the WOLED electroluminescent functional layer.

8. A display device comprising the bottom emission white organic light emitting diode display panel as claimed in any one of claims 1 to 7, and a polarizing layer disposed on the other side of the substrate.

9. A method for manufacturing a bottom emission white organic light emitting diode display panel comprises the following steps:

s10, providing a substrate;

s20, manufacturing and forming a thin film transistor on the substrate, and forming a first protective layer on the thin film transistor;

s30, forming a WOLED color film layer on the first protection layer, wherein red, green, blue and white pixels are sequentially formed on the WOLED color film layer, and a second protection layer is formed on the WOLED color film layer;

s40, forming a quantum dot photoconversion layer on the second protection layer, wherein the quantum dot photoconversion layer comprises quantum dot red and green luminous materials filled corresponding to the red and green pixels, and forming a resin layer or a flat layer on the quantum dot photoconversion layer;

s50, forming a first electrode on the resin layer or the flat layer, and defining a red, green, blue and white pixel region on the first electrode;

and S70, forming a second electrode on the WOLED electroluminescence function layer, wherein the blue light or the yellow light of the WOLED electroluminescence function layer is converted into red light and green light through the quantum dot red-green luminescent material of the quantum dot photoconversion layer, so that the brightness of the red pixel and the green pixel is improved.

10. The method as claimed in claim 9, wherein in step S40, the quantum dot photoconversion layer is formed by inkjet printing, nozzle printing or transfer molding, and the quantum dot photoconversion layer further fills red/green phosphors in corresponding red/green pixel regions, the red/green phosphors are not filled in the blue/white pixel regions, and the quantum dot photoconversion layer is a quantum dot enhanced film with a thickness of 10-200 nm.

11. The method of claim 9, wherein in step S60, the WOLED electroluminescent functional layer comprises any one of blue light + yellow light, blue light + red light + yellow light + green light, or blue light + red light + green light.

12. The method of claim 9, wherein after step S60, a blank layer or a pixel defining layer is further formed on the first electrode, wherein the blank layer or the pixel defining layer is adjacent to the WOLED electroluminescent functional layer and defines the rgb-white pixel regions.

13. The method of claim 9, wherein step S30 comprises coating a resin material or depositing silicon oxide on the thin film transistor and forming a pattern by developing and exposing to form the first passivation layer.

14. The method of claim 9, further comprising a cover glass covering the second electrode and an encapsulant adhering to and encapsulating the substrate and the cover glass after step S70, wherein the encapsulant is selected from a group consisting of a dam encapsulation, a dam-fill encapsulation, a frit encapsulation, a surface-sealed encapsulation, and a film encapsulation.