WO2020211232A1

WO2020211232A1 - Photoresist and display panel

Info

Publication number: WO2020211232A1
Application number: PCT/CN2019/101904
Authority: WO
Inventors: 刘国和
Original assignee: 深圳市华星光电技术有限公司
Priority date: 2019-04-19
Filing date: 2019-08-22
Publication date: 2020-10-22
Also published as: CN110058491A

Abstract

A photoresist and a display panel. The photoresist comprises a resin, a photosensitizer, a polymer monomer, a solvent, and an ultraviolet light absorptive particle. The ultraviolet light absorbing particle is used for absorbing ultraviolet light emitted into the photoresist. By introducing an ultraviolet light absorbing particle to the photoresist, part of DUV and EUV ultraviolet light can be absorbed in a DUV substrate clean process and an EUV substrate clean process of a display panel respectively so as to reduce damage of the DUV/EUV ultraviolet light to the photoresist, to reduce the effect of the DUV/EUV substrate clean process to a photoresist material film in the display panel, and to inhibit the occurrence of gas escape of the photoresist material film, thereby reducing ionic concentration in a liquid crystal layer of an LCD panel and improving the quality of display of an LCD.

Description

Photoresist and display panel

Technical field

The present invention relates to the field of display technology, in particular to a photoresist and a display panel.

Background technique

Thin Film Transistor Liquid Crystal Display (TFT-LCD) has many advantages such as thin body, power saving, and no radiation, and has been widely used. Most of the liquid crystal display devices on the existing market are backlight liquid crystal display devices, which include a liquid crystal display panel and a backlight module (backlight module). Generally, a liquid crystal display panel is composed of a color filter (CF) substrate, a TFT array substrate, a liquid crystal (LC) sandwiched between the color filter substrate and the TFT array substrate, and a sealant (Sealant). The CF substrate is the main device used by the LCD to achieve color display, and its basic composition usually includes: a glass substrate, a black matrix (Black Matrix, BM), a color filter layer, and so on. Among them, the color filter layer mainly achieves the effect of color display through color photoresist. The light emitted by the backlight is modulated by liquid crystal molecules and enters the CF substrate, and passes through the red (R) photoresist and green photoresist of the color filter layer on the CF substrate. The light filtering function of (G) photoresist and blue (B) photoresist respectively displays red, green, and blue light, and different color photoresists respectively transmit light of corresponding color bands, thereby realizing the color display of the display.

As an important raw material in the TFT-LCD industry, photoresist is widely used in the production of modern panels, such as the black matrix on the CF substrate side, the color filter layer RGB color resist, the over coat (OC) and the spacer (photo spacer, PS), etc., and the organic insulating flat layer (Polymer Film on Array, PFA) on the side of the TFT array substrate. This type of photoresist material will be retained as a direct material in the panel. Therefore, the stability of such materials, such as heat resistance, chemical resistance, and light resistance, is particularly important to the quality of the panel.

In the TFT-LCD manufacturing process, the cleanliness of the substrate has a crucial influence on the yield and quality of the panel. Deep ultraviolet light Ultraviolet, DUV) or extreme ultraviolet light (Extreme Ultraviolet (EUV), as the most effective method to remove organic pollutants, is widely used in the cleaning process of TFT-LCD substrates. The principle of DUV or EUV ultraviolet light cleaning is to use 254nm or 172nm ultraviolet light to break the chemical bonds of the solvent or organic matter remaining on the substrate, thereby carbonizing and decomposing the residual organic matter into gas for removal or decomposing it into low molecular weight. The polymer is then cleaned with lye or chemical solution to completely remove the organic residue on the substrate.

DUV or EUV cleaning is the most effective method to remove organic residues on the substrate. The wavelength corresponds to 254nm and 172nm respectively. The photon energy is sufficient to break most of the chemical bonds in the photoresist resin, such as the acrylic resin commonly used in photoresist, so as to make acrylic The resin is broken or decomposed to produce outgas. The outgas produced by decomposition is extremely unfavorable for TFT-LCD. There are two main influences: (1) After the CF substrate and TFT array substrate are assembled into a cell, outgas slowly escapes and rushes into the liquid crystal to produce liquid crystal bubbles ( bubble); (2) the outgas rushing into the liquid crystal contaminates the liquid crystal, and the increase of ion concentration causes afterimage (image Sticking) occurs, thereby affecting the display quality of TFT-LCD.

technical problem

The purpose of the present invention is to provide a photoresist, which can reduce the influence of the DUV/EUV substrate cleaning process on the photoresist material film layer in the display panel, and inhibit the occurrence of gas escape from the photoresist material film layer.

The object of the present invention is also to provide a display panel, which can reduce the influence of the DUV/EUV substrate cleaning process on the photoresist material film layer in the display panel, and inhibit the occurrence of gas escape from the photoresist material film layer.

Technical solutions

In order to achieve the above objective, the present invention provides a photoresist, including resin, sensitizer, polymer monomer, solvent, and ultraviolet light absorbing particles, and the ultraviolet light absorbing particles are used for the photoresist. The ultraviolet light is absorbed.

The ultraviolet light absorbing particles are inorganic nanoparticles; the band gap of the ultraviolet light absorbing particles is 4.5-8.5 eV.

The ultraviolet light absorbing particles include one or more of SiO ₂ nanoparticles, GeO ₂ nanoparticles, and Ga ₂ O ₃ nanoparticles.

The particle size of the ultraviolet light absorbing particles is 1-50 nm.

The weight percentage of the ultraviolet light absorbing particles in the photoresist is 0.1%-2%.

The ultraviolet light absorbing particles are distributed in the photoresist by physical blending.

The photoresist is a color photoresist, which also includes a colorant and a dispersant, and is used to prepare the color filter layer in the display panel;

The weight percentages of the solvent, resin, polymer monomer, and sensitizer in the photoresist are 80-90%, 5-8%, 5-8%, and 0.2-0.6%, respectively.

The colorant is a pigment, dye or a combination of both.

The photoresist is a transparent photoresist, which is used to prepare the organic insulating layer on the side of the array substrate;

The weight percentages of the solvent, resin, polymer monomer, and sensitizer in the photoresist are 80-85%, 10-15%, 5-8%, and 2-5%, respectively.

The present invention also provides a display panel, including a photoresist film layer prepared from the photoresist described above.

Beneficial effect

The beneficial effects of the present invention: the photoresist of the present invention includes a resin, a sensitizer, a polymer monomer, a solvent, and ultraviolet light absorbing particles, and the ultraviolet light absorbing particles are used to prevent ultraviolet rays that enter the photoresist. Light absorption, by introducing ultraviolet light absorbing particles into the photoresist, part of the DUV and EUV ultraviolet light can be absorbed in the DUV substrate cleaning process and EUV substrate cleaning process of the display panel, thereby reducing the effect of DUV/EUV ultraviolet light on lithography The destruction of the glue reduces the influence of the DUV/EUV substrate cleaning process on the photoresist material film in the display panel, and inhibits the occurrence of gas escape from the photoresist material film, thereby reducing the ion concentration in the liquid crystal layer of the LCD panel and improving the LCD Display quality. The display panel of the present invention includes the photoresist film layer prepared from the above photoresist, which can effectively reduce the influence of the DUV/EUV substrate cleaning process on the photoresist material film layer in the display panel, and inhibit the photoresist material film layer The occurrence of outgassing further reduces the ion concentration in the liquid crystal layer of the LCD panel and improves the display quality of the LCD.

Description of the drawings

The technical solutions and other beneficial effects of the present invention will be made obvious by describing the specific embodiments of the present invention in detail below in conjunction with the accompanying drawings.

In the attached picture,

FIG. 1 is a schematic structural diagram of a preferred embodiment of the display panel of the present invention.

Embodiments of the invention

In order to further illustrate the technical means adopted by the present invention and its effects, the following will describe in detail in combination with the preferred embodiments of the present invention.

The present invention first provides a photoresist, comprising a resin, a sensitizer, a polymer monomer, a solvent, and at least one kind of ultraviolet light absorbing particles, and the ultraviolet light absorbing particles are used to protect the ultraviolet light entering the photoresist. Light absorbs.

Specifically, the ultraviolet light absorbing particles are inorganic nanoparticles; the band gap of the ultraviolet light absorbing particles is 4.5-8.5 eV.

Specifically, the ultraviolet light absorbing particles can be selected from SiO ₂ (silicon oxide) nanoparticles, GeO ₂ (germanium oxide) nanoparticles, Ga ₂ O ₃ (calcium oxide) nanoparticles and other nanoparticles with ultraviolet light absorption properties. Among them, the band gaps corresponding to SiO ₂ nanoparticles, GeO ₂ nanoparticles, and Ga ₂ O ₃ nanoparticles are about 8ev, 5.04ev, and 4.9ev, respectively.

Specifically, the particle size of the ultraviolet light absorbing particles is 1-50 nm.

Specifically, the weight percentage of the ultraviolet light absorbing particles in the photoresist is 0.1%-2%.

Specifically, the ultraviolet light absorbing particles are distributed in the photoresist by means of physical blending.

Specifically, the photoresist may be a color photoresist, which also includes a colorant and a dispersant for preparing a color filter layer; the solvent, resin, polymer monomer, and sensitizer are used in the photolithography The weight percentages in the glue are respectively 80-90%, 5-8%, 5-8% and 0.2-0.6%; wherein, the colorant is a pigment, a dye or a combination of the two.

Alternatively, the photoresist may also be a transparent photoresist for preparing the organic insulating layer (PFA) on the side of the array substrate; the solvent, resin, polymer monomer, and sensitizer are in the photoresist The weight percentages are 80-85%, 10-15%, 5-8% and 2-5% respectively.

The photoresist of the present invention includes a resin, a sensitizer, a polymer monomer, a solvent, and ultraviolet light absorbing particles. The ultraviolet light absorbing particles are used to absorb the ultraviolet light that enters the photoresist. The introduction of ultraviolet light absorbing particles into the photoresist can absorb part of the DUV and EUV ultraviolet light in the DUV substrate cleaning process and EUV substrate cleaning process of the display panel respectively, thereby reducing the damage of DUV/EUV ultraviolet light to the photoresist and reducing DUV The impact of the EUV substrate cleaning process on the photoresist material film layer in the display panel can inhibit the occurrence of outgassing from the photoresist material film layer, thereby reducing the ion concentration in the liquid crystal layer of the LCD panel and improving the display quality of the LCD.

Please refer to FIG. 1, based on the above photoresist, the present invention also provides a display panel, including a photoresist film layer prepared from the above photoresist.

FIG. 1 is a schematic structural diagram of a preferred embodiment of a display panel of the present invention. As shown in FIG. 1, this embodiment includes an upper substrate 1 and a lower substrate 2 arranged oppositely and arranged between the upper substrate 1 and the lower substrate 2 The liquid crystal layer 3 and the spacer 4 of the upper substrate, wherein the upper substrate includes a first base substrate 11 and a black matrix 12 arranged on the side of the first base substrate 11 close to the lower substrate 2; the lower substrate 2 includes The TFT substrate 21 and the color filter layer 22 and the organic insulating layer 23 which are sequentially disposed on the side of the TFT substrate 21 close to the upper substrate 1.

Specifically, the color filter layer 22 includes a red color resist layer 221, a green color resist layer 222, and a blue color resist layer 223 arranged side by side.

Specifically, the organic insulating layer 23, the red color resist layer 221, the green color resist layer 222, and the blue color resist layer 223 are all the photoresist film layers, and all include the ultraviolet light absorbing particles 50.

Specifically, the preparation process of the photoresist used to form the red color resist layer 221, the green color resist layer 222, and the blue color resist layer 223 is to illuminate the colorant, the dispersant, and the surface-treated ultraviolet light absorbing particles 50 A certain proportion is pre-mixed, and then after the disperser is finely processed, it is stirred and filtered in a stirring tank to form a uniformly dispersed intermediate product; the dispersed intermediate product is then mixed with resin, polymer monomer, sensitizer, solvent, Additives, etc. are circulated and filtered in the stirring tank to be uniform, and finally form uniformly dispersed and stable photoresist for forming the RGB color resist layer, wherein the weight percentage of the solvent is 80-90%, and the resin The weight percentage is 5-8%, the weight percentage of the polymer monomer is 5-8%, the weight percentage of the photosensitizer is 0.2-0.6%, and the weight percentage of ultraviolet light absorbing particles is 0.1% -2%, the weight percentage of additives is <1%.

Specifically, the preparation process of the photoresist used to form the organic insulating layer 23 is to circulate and stir the resin, photosensitizer, solvent, additives, and surface-treated ultraviolet light absorbing particles in a stirring tank in a certain proportion. , Filter to uniformity, and finally form a stable and uniformly dispersed photoresist, wherein the weight percentage of solvent is 80-85%, the weight percentage of resin is 0-15%, and the weight percentage of sensitizer is 2 -5%, the weight percentage of ultraviolet light absorbing particles is 0.1%-2%, and the weight percentage of additives is between 0-2%.

Further, the manufacturing process of the display panel of this embodiment specifically includes the following steps:

Step S1, a TFT substrate 21 is provided, and a red color resist layer 221 of the color filter layer 22 is formed on the TFT substrate 21 side.

Step S2: DUV cleaning or EUV cleaning is performed on the TFT substrate 21, since DUV (254nm) or EUV (172nm) ultraviolet light irradiated on the red color resist layer 221 will be absorbed by the ultraviolet light in the red color resist layer 221 50 is partially absorbed, which can effectively reduce the damage caused by DUV/EUV ultraviolet light to the resin in the red color resist layer 221 on the substrate and cause bond breaking; then the green color of the color filter layer 22 is formed on the TFT substrate 21 side Color resist layer 222.

Step S3. Perform DUV cleaning or EUV cleaning on the TFT substrate 21. At this time, the ultraviolet light absorbing particles 50 in the red color resist layer 221 and the green color resist layer 222 will absorb part of the short-wave ultraviolet light, which can effectively reduce DUV/EUV The ultraviolet light damages the resin in the red color resist layer 221 and the green color resist layer 222 on the substrate; then the blue color resist layer 223 of the color filter layer 22 is formed on the TFT substrate 21 side to obtain the color Filter layer 22.

Step S4, DUV cleaning treatment or EUV cleaning treatment is performed on the TFT substrate 21. During the cleaning process, the ultraviolet light absorbing particles 50 in the red color resist layer 221, the green color resist layer 222 and the blue color resist layer 223 will absorb part of the short-wave ultraviolet light Therefore, it can effectively reduce the damage caused by DUV/EUV ultraviolet light to the resin in the red color resist layer 221, green color resist layer 222 and blue color resist layer 223 on the substrate, thereby reducing the overall generation of photoresist outgassing. Then, the organic insulating layer 23 is formed on the TFT substrate 21 and the color filter layer 22 to obtain the lower substrate 2.

Step S5, the upper substrate 1 is provided, and the lower substrate 2 and the upper substrate 1 are paired into a box to obtain a display panel.

The display panel of the present invention includes a photoresist film layer containing ultraviolet light absorbing particles 50, which can effectively reduce the impact of the DUV/EUV substrate cleaning process on the photoresist material film layer in the display panel, and inhibit light The occurrence of outgassing from the resist material film layer reduces the ion concentration in the liquid crystal layer of the LCD panel and improves the display quality of the LCD.

In summary, the photoresist of the present invention includes resin, sensitizer, polymer monomer, solvent, and ultraviolet light absorbing particles, and the ultraviolet light absorbing particles are used to prevent ultraviolet light entering the photoresist. Absorption, by introducing ultraviolet light absorbing particles into the photoresist, part of the DUV and EUV ultraviolet light can be absorbed in the DUV substrate cleaning process and EUV substrate cleaning process of the display panel, thereby reducing the effect of DUV/EUV ultraviolet light on the photoresist It reduces the impact of the DUV/EUV substrate cleaning process on the photoresist material film in the display panel, inhibits the occurrence of gas out of the photoresist material film, thereby reducing the ion concentration in the liquid crystal layer of the LCD panel, and improving the LCD Display quality. The display panel of the present invention includes the photoresist film layer prepared from the above photoresist, which can effectively reduce the influence of the DUV/EUV substrate cleaning process on the photoresist material film layer in the display panel, and inhibit the photoresist material film layer The occurrence of outgassing further reduces the ion concentration in the liquid crystal layer of the LCD panel and improves the display quality of the LCD.

As mentioned above, for those of ordinary skill in the art, various other corresponding changes and modifications can be made according to the technical solutions and technical ideas of the present invention, and all these changes and modifications shall fall within the protection scope of the claims of the present invention. .

Claims

A photoresist includes a resin, a sensitizer, a polymer monomer, a solvent, and ultraviolet light absorbing particles, and the ultraviolet light absorbing particles are used for absorbing the ultraviolet light that enters the photoresist.
3. The photoresist of claim 1, wherein the ultraviolet light absorbing particles are inorganic nanoparticles; the band gap of the ultraviolet light absorbing particles is 4.5-8.5 eV.
3. The photoresist of claim 2, wherein the ultraviolet light absorbing particles comprise one or more of SiO 2 nanoparticles, GeO 2 nanoparticles, and Ga 2 O 3 nanoparticles.
3. The photoresist of claim 1, wherein the ultraviolet light absorbing particles have a particle size of 1-50 nm.
8. The photoresist of claim 1, wherein the weight percentage of the ultraviolet light absorbing particles in the photoresist is 0.1%-2%.
8. The photoresist of claim 1, wherein the ultraviolet light absorbing particles are distributed in the photoresist by physical blending.
The photoresist of claim 1, which is a color photoresist, further comprising a colorant and a dispersant, and is used to prepare a color filter layer;

The weight percentages of the solvent, resin, polymer monomer, and sensitizer in the photoresist are 80-90%, 5-8%, 5-8%, and 0.2-0.6%, respectively.
8. The photoresist of claim 7, wherein the colorant is a pigment, a dye, or a combination of both.
The photoresist according to claim 1, which is a transparent photoresist and is used to prepare the organic insulating layer on the side of the array substrate;

The weight percentages of the solvent, resin, polymer monomer, and sensitizer in the photoresist are 80-85%, 10-15%, 5-8%, and 2-5%, respectively.
A display panel includes a photoresist film layer, and the photoresist film layer is prepared from photoresist;

The photoresist includes a resin, a sensitizer, a polymer monomer, a solvent, and ultraviolet light absorbing particles, and the ultraviolet light absorbing particles are used to absorb ultraviolet light incident on the photoresist.
10. The display panel of claim 10, wherein the ultraviolet light absorbing particles are inorganic nanoparticles; the band gap of the ultraviolet light absorbing particles is 4.5-8.5 eV.
11. The display panel of claim 11, wherein the ultraviolet light absorbing particles comprise one or more of SiO 2 nanoparticles, GeO 2 nanoparticles, and Ga 2 O 3 nanoparticles.
10. The display panel of claim 10, wherein the ultraviolet light absorbing particles have a particle size of 1-50 nm.
10. The display panel of claim 10, wherein the weight percentage of the ultraviolet light absorbing particles in the photoresist is 0.1%-2%.
10. The display panel of claim 10, wherein the ultraviolet light absorbing particles are distributed in the photoresist by physical blending.
10. The display panel of claim 10, wherein the photoresist is a color photoresist, further comprising a coloring agent and a dispersing agent for preparing a color filter layer;

The weight percentages of the solvent, resin, polymer monomer, and sensitizer in the photoresist are 80-90%, 5-8%, 5-8%, and 0.2-0.6%, respectively.
The display panel of claim 16, wherein the colorant is a pigment, a dye, or a combination of both.
10. The display panel of claim 10, wherein the photoresist is a transparent photoresist for preparing an organic insulating layer on the side of the array substrate;

The weight percentages of the solvent, resin, polymer monomer, and sensitizer in the photoresist are 80-85%, 10-15%, 5-8%, and 2-5%, respectively.