CN115536545A

CN115536545A - Surfactant, preparation method thereof, photoresist and photoetching method

Info

Publication number: CN115536545A
Application number: CN202211219048.2A
Authority: CN
Inventors: 姜庆; 袁海江
Original assignee: HKC Co Ltd
Current assignee: HKC Co Ltd
Priority date: 2022-09-29
Filing date: 2022-09-29
Publication date: 2022-12-30

Abstract

The application provides a surfactant, a preparation method thereof, a photoresist and a photoetching method. The surfactant comprises at least one azo group, one nitrogen element in the azo group is connected with a first group, the other nitrogen element is connected with a second group, the surfactant has a trans-structure and a cis-structure, and when the surfactant meets a preset condition, the surfactant is converted from the trans-structure to the cis-structure; the first group and/or the second group comprises an ester group comprising a halogen. By adopting the surfactant comprising the azo group and the ester group containing the halogen, the anti-static defoaming agent not only can be converted into a cis structure from a trans structure, but also can enable the surfactant to be in a state of rich positive charge inhibition and uniform charge distribution, is not easy to form bubbles, and enables the formed bubbles to be easily destroyed, so that the defoaming effect of the surfactant is improved. When the surfactant is applied to a photoetching process, the foaming phenomenon can be inhibited, the manufacturing cost is reduced, and the productivity is improved.

Description

Surfactant, preparation method thereof, photoresist and photoetching method

Technical Field

The application belongs to the technical field of photoetching, and particularly relates to a surfactant, a preparation method thereof, a photoresist and a photoetching method.

Background

The photolithography process usually requires coating, exposure, and development. The surfactant of the photoresist has the performance of improving the solubilization, emulsification, dispersion and the like of a photoresist system. However, showering is often used in the development process. The spraying makes the air enter the photoresist and the developing solution, so that the surfactant and the air or other substances interact to form bubbles, the foaming phenomenon is easy to occur in the developing process, foreign matters are easy to appear in the product, the filtering filter element for recovering the developing solution is easy to block, the manufacturing cost is increased, and the productivity is reduced.

Disclosure of Invention

In view of this, the first aspect of the present application provides a surfactant comprising at least one azo group, wherein one nitrogen element of the azo group is connected to a first group, and the other nitrogen element of the azo group is connected to a second group, the surfactant has a trans structure and a cis structure, and when the surfactant satisfies a predetermined condition, the surfactant is converted from the trans structure to the cis structure;

wherein the trans structure is:

the cis structure is:

R ₁ represents said first group, R ₂ Represents said second group, said first group and/or said second group comprising an ester group comprising a halogen.

The surfactant provided by the first aspect of the present application comprises at least one azo group to provide a basis for the conversion of a trans structure to a cis structure. Wherein trans-structure means that the first group and the second group are on either side of the nitrogen-nitrogen double bond, respectively. The cis configuration refers to the first group being on the same side of the nitrogen-nitrogen double bond as the second group.

First, the surfactant in its natural state is generally trans-structured. In this case, the surfactant has the property of improving the solubility, emulsifying property, dispersibility and the like of the photoresist system. However, the surfactant solution of the trans structure forms bubbles with air or other substances.

And when the surfactant satisfies a predetermined condition, the surfactant can be converted from a trans-structure to a cis-structure. The cis-structured surfactant can reduce the surface tension compared to the trans-structured surfactant, so that bubbles are easily broken, and thus the foaming phenomenon can be suppressed. Meanwhile, the surfactant with the cis-structure can also increase the critical micelle concentration, the interface energy, the steric hindrance effect and the interaction enthalpy, and the surfactant is easy to agglomerate and is difficult to form bubbles, so that the formation of the bubbles is further inhibited.

In addition, the first group and/or the second group comprise an ester group containing halogen, so that the surfactant can be in a state of abundant positive charges and uniform charge distribution, the surface tension is further reduced, and the defoaming effect of the surfactant is further improved.

Therefore, the surfactant containing the azo group and the ester group containing the halogen is adopted, so that the trans structure can be converted into the cis structure, bubbles are not easily formed, and the formed bubbles are easily destroyed, so that the defoaming effect of the surfactant is improved. When the surfactant is applied to a photolithography process, a foaming phenomenon can be suppressed, thereby reducing the manufacturing cost and improving the productivity.

Wherein the halogen-containing ester group comprises a trihalo-carbethoxy group, or a dihalo-carbethoxy group, or a monohalo-carbethoxy group; wherein the halogen comprises one or more of fluorine, chlorine, bromine, and iodine.

Wherein the preset condition comprises at least one of the following conditions:

exposing the surfactant by adopting ultraviolet light of 350nm-450 nm;

the exposure time is 1s-5s.

In a second aspect, the present application provides a method for preparing a surfactant, comprising:

providing a first compound containing an azo group, a halogenated hydrocarbon, an initiator, and a first organic solvent;

mixing the first compound, the halogenated hydrocarbon, the initiator and the first organic solvent for reaction and heating to obtain a second compound containing the azo group and the halogenated hydrocarbon group;

mixing the second compound, a compound containing trimethylamine and a second organic solvent for reaction to obtain a third compound containing the azo group, the trimethylamine and halogen; and

and mixing and reacting the third compound, a compound containing a halogen ester group, and a third organic solvent to obtain the surfactant containing the azo group, the trimethylamine, and the halogen ester group.

The preparation method of the surfactant provided by the second aspect of the application has the advantages of simple process and strong operability.

First, a first compound, a halogenated hydrocarbon, an initiator, and a first organic solvent are mixed and reacted, and heated to replace an element or a group in the first compound with a halogenated hydrocarbon group, thereby obtaining a second compound containing an azo group and a halogenated hydrocarbon group. Then, the second compound, the trimethylamine-containing compound, and the second organic solvent are mixed and reacted to replace the second compound element or group with trimethylamine, and the halogen in the halohydrocarbon group is changed to a halogen that is coordinated with trimethylamine, thereby obtaining a third compound containing an azo group, trimethylamine, and halogen. Finally, the third compound, the compound containing the halogen ester group, and the third organic solvent are mixed and reacted to replace the halogen in the third compound with the halogen ester group, thereby obtaining the surfactant containing the azo group, the trimethylamine, and the halogen ester group.

Therefore, the surfactant prepared by the preparation method contains azo groups and ester groups containing halogen, can be converted from a trans-structure to a cis-structure, can enable the surfactant to be in a state of inhibiting positive charges from being rich and enabling the charges to be distributed uniformly, is not easy to form bubbles, and enables the formed bubbles to be easily destroyed, so that the defoaming effect of the surfactant is improved. And, when the surfactant of the present application is applied to a photolithography process, a foaming phenomenon can be suppressed, thereby reducing manufacturing costs and improving productivity.

Wherein the step of reacting the second compound, the trimethylamine-containing compound and the second organic solvent in a mixed state comprises:

providing an aqueous solution comprising trimethylamine;

heating the aqueous solution containing trimethylamine to obtain a gas containing trimethylamine;

and mixing and reacting the gas containing the trimethylamine with the second compound and a second organic solvent to obtain a third compound containing the azo group, the trimethylamine and the halogen.

Wherein the molar ratio of the third compound to the compound containing a halogen-containing ester group is 1: (1-3).

A third aspect of the present application provides a photoresist comprising a resin, an additive, a solvent, and a surfactant as provided in the first aspect of the present application.

The photoresist that this application third aspect provided through adopting the above-mentioned surfactant that provides of this application, not only can change into the cis-form structure from trans structure, can make surfactant active moreover be in and restrain the positive charge abundant, and the even state of charge distribution, neither easily forms the bubble, makes the bubble after forming destroyed easily again to improve surfactant's defoaming effect. Therefore, when the photoresist is applied to a photolithography process, a bubble phenomenon can be suppressed, thereby reducing manufacturing cost and improving productivity.

Wherein, in the photoresist, the mass fraction of the surfactant is 0.1-2%.

A fourth aspect of the present application provides a lithographic method, comprising:

providing a piece to be photoetched and a photoresist as provided in the third aspect of the present application;

coating the photoresist on the piece to be photoetched;

exposing the photoresist coated on the piece to be photoetched;

pretreating the photoresist coated on the piece to be subjected to photoetching to enable the surfactant in the photoresist to meet a preset condition so as to enable the surfactant to be converted from the trans-structure into the cis-structure;

and developing the pretreated photoresist.

The photoetching method provided by the fourth aspect of the application is simple in process and strong in operability. Through adopting the above-mentioned photoresist that provides of this application, and before carrying out the development to the photoresist, make the surfactant active of photoresist convert the cis-form structure into from trans-form structure, neither easily form the bubble, make the bubble after forming again easily destroyed to improve surfactant active's defoaming effect, restrain the bubbling phenomenon, thereby reduce manufacturing cost, improve the productivity.

Wherein the pretreatment comprises exposure, and the photoresist coated on the piece to be photoetched is exposed;

the step of pretreating the photoresist coated on the piece to be photoetched to enable the surfactant in the photoresist to meet a preset condition so as to enable the surfactant to be converted from the trans-structure into the cis-junction comprises the following steps:

and exposing the photoresist coated on the piece to be photoetched to solidify the photoresist, and enabling the surfactant in the photoresist to meet a preset condition, so that the surfactant is converted from the trans-structure to the cis-structure.

Drawings

In order to more clearly describe the technical solutions in the embodiments of the present application, the drawings that are required to be used in the embodiments of the present application will be described below.

FIG. 1 is a UV-Vis spectrum of a surfactant.

Fig. 2 is a graph of surface tension data for trans-structured surfactants and cis-structured surfactants at different concentrations.

FIG. 3 is a graph showing the effect of foaming performance of surfactants in trans and cis structures.

Fig. 4 is a process flow diagram of a method of preparing a surfactant according to an embodiment of the present disclosure.

Fig. 5 is a process flow diagram included in S300 according to an embodiment of the present disclosure.

FIG. 6 is a target pattern prepared without using the photoresist of the present application.

FIG. 7 is a target pattern prepared using the photoresist of the present application.

FIG. 8 is a process flow diagram of a photolithography method in accordance with an embodiment of the present application.

Fig. 9 is a flowchart of processes included in S30 and S40 according to an embodiment of the present disclosure.

Detailed Description

The following is a preferred embodiment of the present application, and it should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present application, and these improvements and modifications are also considered as the protection scope of the present application.

Referring to fig. 1-3 together, fig. 1 is a uv-vis spectrum of a surfactant. Fig. 2 is a graph of surface tension data for trans-structured surfactants and cis-structured surfactants at different concentrations. FIG. 3 is a graph showing the effect of foaming performance of surfactants in trans-structure and cis-structure.

In each of FIGS. 1 to 3, the surfactant content in the TMAH developer was 2.38% by weight. Wherein the surfactant comprises 4-butylazobenzene-4- (hexyloxy) trimethyl ammonium bromide.

The embodiment provides a surfactant, which comprises at least one azo group, wherein one nitrogen element in the azo group is connected with a first group, the other nitrogen element is connected with a second group, the surfactant has a trans-structure and a cis-structure, and when the surfactant meets a preset condition, the surfactant is converted from the trans-structure to the cis-structure.

Wherein, the trans structureComprises the following steps:

the cis structure is:

Furthermore, the terms "include" and "have," as well as any variations thereof, are intended to cover non-exclusive inclusions.

The surfactant provided by the present embodiment can have the performances such as solubilizing performance, emulsifying performance, and dispersing performance. Alternatively, the surfactant is applied to a photoresist, a water treatment agent, a petroleum contamination treatment agent, liquid film separation, and the like. In the present embodiment, the application of the surfactant is not limited, and the application of the surfactant to the photoresist will be schematically described.

The surfactant provided by the present embodiment includes at least one azo group to effect conversion from a trans structure to a cis structure. Wherein trans-structure means that the first group and the second group are on either side of the nitrogen-nitrogen double bond. The cis configuration refers to the first group being on the same side of the nitrogen-nitrogen double bond as the second group. Specifically, as shown in fig. 1, when the surfactant satisfies a preset condition, the surfactant is converted from a trans structure to a cis structure. The preset conditions include, but are not limited to, optical, electrical, magnetic, etc. conditions to convert at least a portion of the surfactant in the trans structure to the surfactant in the cis structure. In other words, the surfactant exists in a molecular state of trans form in a natural state, and when a predetermined condition is satisfied, the molecule of the surfactant is isomerized from the trans form to a cis form.

Referring to fig. 1, fig. 1 is a uv-vis spectrum of surfactant irradiated under 365nm uv for 0s, 1s and 3.5s, respectively. It can be seen from the figure that the designed photoresponsive surfactant exists in a trans structure when ultraviolet irradiation is not carried out, 32.8% of the trans structure is converted into a cis structure when the ultraviolet irradiation is carried out for 1s, and 94.3% of the photoresponsive surfactant is isomerized into the cis structure after the ultraviolet irradiation is carried out for 3.5s, which shows that the surfactant molecule with the structure has excellent isomerization performance, can rapidly increase the steric hindrance of an added system, and can inhibit the formation of bubbles.

In one embodiment, when the preset condition is exposure, the preset condition includes at least one of the following cases: exposing the surfactant by adopting ultraviolet light of 350nm-450 nm; the exposure time is 1s-5s. It should be noted that the surfactant herein is similar to a photoswitch, and when the surfactant is excited by light, the molecules of the surfactant are isomerized from trans-form to cis-form.

Optionally, the wavelength of the light exposed is 365nm, 385nm, 395nm, 415nm, 435nm; the exposure time was 2s, 3s, 3.5s, 4s.

The wavelength range of the exposed light is 350nm-450nm, so that the surfactant can be fully converted from a trans structure to a cis structure; but also can save cost and reduce energy consumption. If the wavelength of the light to be exposed is less than 350nm, the surfactant cannot be sufficiently converted from a trans structure to a cis structure, and the defoaming effect of the surfactant is reduced; if the wavelength of the light to be exposed is greater than 450nm, the cost is increased, the energy consumption is increased, and it is not possible to ensure that the surfactant can be converted from a trans structure to a cis structure, thereby reducing the defoaming effect of the surfactant.

The exposure time is 1s-5s, so that the surfactant can be fully converted from a trans structure to a cis structure; but also can save cost and reduce energy consumption. If the exposure time is less than 1s, it is not possible to ensure that the surfactant can be sufficiently converted from the trans structure to the cis structure, so that the amount of the surfactant having the cis structure is reduced, and the defoaming effect of the surfactant is reduced; if the exposure time is longer than 5s, the cost increases and the power consumption increases.

The surfactant provided by this embodiment further includes a first group and a second group, which are coordinated with each other with the azo group, so that the surfactant has a trans structure and a cis structure. In the present embodiment, the first group and the second group include groups without limitation. Alternatively, the first group is the same as the second group. Optionally, the first group is different from the second group. Optionally, the first group and/or the second group comprises one or more of an alkyl group, an aryl group, an alkoxy group, and a haloalkyl group. Further optionally, the number of carbon elements of the first group and/or the second group is 1-10. For example: propyl, ethoxy, dibromohexyl, phenolic hydroxyl, and the like.

The surfactant provided by the embodiment also comprises an ester group containing halogen, so that the surfactant is in a state of rich positive charge and uniform charge distribution, and the defoaming effect of the surfactant is further improved. Wherein the first group and/or the second group comprises an ester group comprising a halogen. In the present embodiment, the number of ester groups containing a halogen and the group to be bonded are not limited. Further, in the present embodiment, the kind and the number of halogens included in the halogen-containing ester group are not limited; the ester group containing a halogen contains no limitation on the number of carbon and hydrogen elements.

In one embodiment, the halogen-containing ester group comprises a trihalo-carbethoxy group, or a dihalo-carbethoxy group, or a monohalo-carbethoxy group; wherein the halogen comprises one or more of fluorine, chlorine, bromine, and iodine. Wherein, when the ester group containing halogen includes trihalo-ethyl ester group, it can be understood as perhalogenated ethyl ester group, at this time, positive charge in the surfactant can be further enriched, and the charge is in a more uniformly distributed state, thereby further improving defoaming effect of the surfactant.

Referring to fig. 2, fig. 2 shows the surface tension of trans-structured surfactant and cis-structured surfactant at different concentrations. In fig. 2, a solid circle represents a trans-structured surfactant, and an open circle represents a cis-structured surfactant.

The data of the surface tension before and after 365nm illumination at the same concentration is measured by a plate-lifting surface tension meter, and as shown in fig. 2, it can be seen from fig. 2 that the critical micelle concentration of the solution after 365nm illumination is increased, the surface tension is reduced, the surfactant is easier to agglomerate, and bubbles are not easy to form. This indicates that the arrangement of the photosensitive surface active molecules at the interface becomes loose, the steric hindrance increases, and foaming is not facilitated.

It should be noted that the surfactant adsorbs a common monomolecular layer in an enrichment manner at the interface, when the surface adsorption is saturated, the surfactant molecules cannot be enriched continuously on the surface, and the hydrophobic effect of the hydrophobic group still strives to promote the hydrophobic group molecules to escape from the water environment, so that the surfactant molecules self-aggregate in the solution, that is, the hydrophobic groups aggregate together to form an inner core, and the hydrophilic group faces outwards to contact with water to form an outer shell, thereby forming the simplest micelle. The concentration of the surfactant at which micelles begin to form is called the critical micelle concentration, CMC for short. When the solution reaches the critical micelle concentration, the surface tension of the solution is reduced to the minimum value, and at the moment, the concentration of the surfactant is increased, so that the surface tension of the solution is not reduced any more and a large amount of micelles are formed.

Referring to fig. 3, fig. 3 shows the foaming performance of surfactants in trans-structure and cis-structure. In fig. 3, solution a represents a trans-structured surfactant, and solution B represents a cis-structured surfactant.

Two colorimetric cylinders were fixed, and the same amount of air was slowly introduced into the trans-structured surfactant and the cis-structured surfactant, and the heights of bubbles generated from the both were observed. It is understood from FIG. 3 that the trans-structured surfactant has a significant height of bubbles, and the cis-structured surfactant does not have bubbles after irradiation with 365nm ultraviolet light. Therefore, the surfactant molecules with the trans-structure are isomerized into cis-structures under 365nm illumination, and the generation of bubbles can be effectively inhibited.

First, surfactants in their natural state are typically trans-structured. In this case, the surfactant has the property of improving the solubility, emulsifying property, dispersibility and the like of the photoresist system. However, the trans-structured surfactant solution forms bubbles with air or other substances.

And, when the surfactant satisfies a predetermined condition, the surfactant can be converted from a trans structure to a cis structure. The cis-structured surfactant can reduce the surface tension compared to the trans-structured surfactant, so that bubbles are easily broken, and thus the foaming phenomenon can be suppressed. Secondly, the cis-structured surfactant can also increase the critical micelle concentration, the interfacial energy, the steric hindrance effect and the enthalpy of interaction, and it can also be understood that the surfactant is more likely to agglomerate and is less likely to form bubbles, so that the formation of bubbles is further suppressed.

And the first group and/or the second group comprise an ester group containing halogen, so that the surfactant is in a state of abundant positive charges and uniform charge distribution, the surface tension is further reduced, and the defoaming effect of the surfactant is further improved.

The application also provides a preparation method of the surfactant. Referring to fig. 4, fig. 4 is a process flow diagram of a method for preparing a surfactant according to an embodiment of the present disclosure. The embodiment provides a preparation method of a surfactant, which comprises S100, S200, S300 and S400. The details of S100, S200, S300, and S400 are as follows.

S100, providing a first compound containing an azo group, a halogenated hydrocarbon, an initiator and a first organic solvent.

The present embodiment provides a first compound containing an azo group, a halogenated hydrocarbon, an initiator, and a first organic solvent. The first compound and the halogenated hydrocarbon are reactants. The initiator serves to initiate, catalyze, and enhance the completion of the reaction, and it is also understood that the initiator enables the reaction to be as complete as possible. The first organic solvent can dissolve the first compound, the halogenated hydrocarbon and the initiator, so that the first compound, the halogenated hydrocarbon and the initiator are fully contacted, and the reaction rate is accelerated.

Optionally, the first compound comprises one or more of butylazo phenol, butylazo, propylazo phenol. The halogenated hydrocarbon comprises one or more of 1,6-dibromohexane, dichlorohexane and dibromopropane. The initiator comprises one or more of sodium hydroxide and potassium hydroxide. The first organic solvent comprises one or more of an ether solvent, a nitrile solvent, an amide solvent, a sulfone solvent, an ester solvent, an alcohol solvent and a hydrocarbon solvent; for example, tetrahydrofuran, absolute ethanol, and the like.

S200, mixing the first compound, the halogenated hydrocarbon, the initiator and the first organic solvent for reaction and heating to obtain a second compound containing the azo group and the halogenated hydrocarbon group.

In the present embodiment, a first compound, a halogenated hydrocarbon, an initiator, and a first organic solvent are mixed and reacted, and heated to replace an element or a group in the first compound with a halogenated hydrocarbon group, thereby obtaining a second compound containing an azo group and a halogenated hydrocarbon group.

Optionally, the molar ratio of the first compound, the halogenated hydrocarbon, the initiator, and the first organic solvent is (3-4): (5-15): 1:50. further optionally, the molar ratio of the first compound, the halogenated hydrocarbon, the initiator, and the first organic solvent is 5: (8-12): 1:50. still further optionally, the molar ratio of the first compound, the halogenated hydrocarbon, the initiator, and the first organic solvent is 5:10:1:50.

the molar ratio of the first compound, the halogenated hydrocarbon, the initiator and the first organic solvent is (3-4): (5-15): 1:50, not only can the first compound be ensured to be fully reacted with the halogenated hydrocarbon; and can save the cost and reduce the energy consumption. If the molar ratio of the first compound, the halogenated hydrocarbon, the initiator, and the first organic solvent is less than (3-4): (5-15): 1:50, it is not possible to ensure that the first compound can react with the halogenated hydrocarbon sufficiently to form enough of the second compound to reduce the amount of surfactant formed in subsequent reactions; if the molar ratio of the first compound, the halogenated hydrocarbon, the initiator, and the first organic solvent is greater than (3-4): (5-15): 1:50, this results in increased costs and increased energy consumption.

Optionally, the first compound, the halogenated hydrocarbon, the initiator, and the first organic solvent are heated at a temperature of 70 ℃ to 90 ℃ for a time of 7h to 9h. Further optionally, the first compound, the halogenated hydrocarbon, the initiator, and the first organic solvent are heated at a temperature of 75 ℃, 78 ℃, 80 ℃, 82 ℃, 86 ℃. The heating time is 7.5h, 8h and 8.5h.

The heating temperature of the first compound, the halogenated hydrocarbon, the initiator and the first organic solvent is 70-90 ℃, so that the first compound can be ensured to be fully reacted with the halogenated hydrocarbon; but also can save cost and reduce energy consumption. If the heating temperature of the first compound, the halogenated hydrocarbon, the initiator and the first organic solvent is less than 70 ℃, the first compound cannot be ensured to be fully reacted with the halogenated hydrocarbon, and the amount of the surfactant generated in the subsequent reaction is reduced; if the heating temperature of the first compound, the halogenated hydrocarbon, the initiator, and the first organic solvent is more than 90 ℃, the cost and the energy consumption are increased.

The heating time of the first compound, the halogenated hydrocarbon, the initiator and the first organic solvent is 7-9h, so that the first compound can be fully reacted with the halogenated hydrocarbon; but also can save cost and reduce energy consumption. If the heating time of the first compound, the halogenated hydrocarbon, the initiator and the first organic solvent is less than 7 hours, the first compound cannot be ensured to be fully reacted with the halogenated hydrocarbon, and the amount of the surfactant generated in the subsequent reaction is reduced; if the first compound, the halogenated hydrocarbon, the initiator, and the first organic solvent are heated for more than 9 hours, the cost and the energy consumption are increased.

Alternatively, in an embodiment, the step of mixing and reacting the first compound, the halogenated hydrocarbon, the initiator and the first organic solvent, and heating to obtain the second compound containing the azo group and the halogenated hydrocarbon group includes:

mixing the first compound, the halogenated hydrocarbon, the initiator and the first organic solvent for reaction and heating; obtaining a second compound after solid-liquid separation; repeatedly leaching the second compound by adopting the first organic solvent and deionized water; drying the second compound; the drying temperature is 50-70 ℃, and the drying time is 10-14h. Further optionally, the drying temperature is 55 ℃, 60 ℃, 65 ℃; the drying time is 11h, 12h and 13h.

And S300, mixing the second compound, the trimethylamine-containing compound and a second organic solvent for reaction to obtain a third compound containing the azo group, the trimethylamine and the halogen.

In the present embodiment, the second compound, the trimethylamine-containing compound, and the second organic solvent are mixed and reacted so that the second compound element or group is replaced with trimethylamine, and the halogen in the halohydrocarbon group is replaced with a halogen that is coordinated to trimethylamine, thereby obtaining a third compound containing an azo group, trimethylamine, and halogen.

The present embodiment provides a trimethylamine-containing compound and a second organic solvent. The second compound and the trimethylamine-containing compound are reactants. The second organic solvent can dissolve the second compound and the trimethylamine-containing compound, so that the second compound and the trimethylamine-containing compound are in full contact with each other, and the reaction rate is increased.

Optionally, the second compound comprises one or more of 4-butylazobenzene-4- (oxy) bromohexane, 4-butylazobenzene-4-bromohexane, butylazo-chlorohexane, propylazophenol-bromopropane. The trimethylamine-containing compound comprises one or more of trimethylamine water and trimethylamine salt. The second organic solvent comprises one or more of an ether solvent, a nitrile solvent, an amide solvent, a sulfone solvent, an ester solvent, an alcohol solvent and a hydrocarbon solvent; for example: tetrahydrofuran, anhydrous ethanol, and the like.

Optionally, the molar ratio of the second compound to the second organic solvent is (1-3): (40-60). Further optionally, the molar ratio of the second compound to the second organic solvent is 2.

Optionally, the time for mixing and reacting the second compound, the trimethylamine-containing compound and the second organic solvent is 0.5h-1.5h. Further optionally, the time for mixing and reacting the second compound, the trimethylamine-containing compound and the second organic solvent is 0.8h, 1h or 1.2h.

The time for mixing and reacting the second compound, the trimethylamine-containing compound and the second organic solvent is 0.5-1.5h, so that the second compound can be fully reacted with the trimethylamine-containing compound; and can save the cost and reduce the energy consumption. If the time for the mixed reaction of the second compound, the trimethylamine-containing compound and the second organic solvent is less than 0.5h, the second compound cannot be sufficiently reacted with the trimethylamine-containing compound, and the amount of the surfactant generated in the subsequent reaction is reduced; if the time for the mixed reaction of the second compound, the trimethylamine-containing compound and the second organic solvent is longer than 1.5 hours, the cost and the energy consumption are increased.

Alternatively, in one embodiment, after the step of obtaining the third compound containing the azo group, the trimethylamine, and the halogen by mixing and reacting the second compound, the compound containing the trimethylamine, and the second organic solvent, the method includes:

standing the third compound for 46-50 h at room temperature; repeatedly leaching the filter cake after rotary evaporation by using a second organic solvent; drying the third compound; the drying temperature is 50-70 ℃, and the drying time is 10-14h. Further optionally, the drying temperature is 55 ℃, 60 ℃, 65 ℃; the drying time is 11h, 12h and 13h. The third compound is recrystallized twice using the first organic solvent.

And S400, mixing and reacting the third compound, the compound containing the halogen ester group and a third organic solvent to obtain the surfactant containing the azo group, the trimethylamine and the halogen ester group.

In the present embodiment, a third compound, a compound having a halogen-containing ester group, and a third organic solvent are mixed and reacted to replace the halogen in the third compound with the halogen-containing ester group, thereby obtaining a surfactant having an azo group, trimethylamine, and halogen-containing ester group.

The present embodiment provides a compound having an ester group containing a halogen and a third organic solvent. The third compound is a reactant with the compound containing the halogen ester group. The third organic solvent can dissolve the second compound and the trimethylamine-containing compound, so that the second compound and the trimethylamine-containing compound are in full contact with each other, and the reaction rate is increased.

The third compound comprises one or more of 4-butylazobenzene-4- (hexyloxy) trimethylammonium bromide, butylazo- (hexane) trimethylammonium chloride, propylazophenol- (propane) trimethylammonium bromide. The compound containing a halogen-containing ester group includes a trihalo-carbethoxy group, a dihalo-carbethoxy group, a monohalo-carbethoxy group; wherein the halogen comprises one of fluorine, chlorine, bromine and iodine; for example; ethyl trichloroacetate, sodium trifluoroacetate, difluoroacetic acid and the like. The third organic solvent comprises one or more of an ether solvent, a nitrile solvent, an amide solvent, a sulfone solvent, an ester solvent, an alcohol solvent and a hydrocarbon solvent; for example: tetrahydrofuran, anhydrous ethanol, and the like.

Further optionally, the third organic solvent comprises a halogen; for example: dichloromethane, trichloromethane, cnH ₂ nCl ₂ And n is 1 to 10, etc. When the third organic solvent comprises halogen, the third organic solvent can provide a stronger electron absorption environment to promote the reaction and improve the yield of the surfactant.

Optionally, the molar ratio of the third compound to the compound containing a halogen-containing ester group is 1: (1-3). Further optionally, the molar ratio of the third compound to the compound containing a halogen-containing ester group is 1:2.

the molar ratio of the third compound to the compound containing the halogen ester group is 1: (1-3) not only ensuring sufficient reaction of the third compound with the compound having a halogen-containing ester group; but also can save cost and reduce energy consumption. If the molar ratio of the third compound to the compound containing a halogen ester group is less than 1: (1-3), it is not possible to ensure that the third compound can sufficiently react with the compound having a halogen ester group, thereby reducing the amount of the surfactant produced; if the molar ratio of the third compound to the compound containing a halogen ester group is greater than 1: (1-3), this results in an increase in cost and an increase in energy consumption.

The preparation method of the surfactant provided by the second aspect of the application has the advantages of simple process and strong operability. The surfactant prepared by the preparation method contains azo groups and ester groups containing halogen, can be converted from a trans structure to a cis structure, and can be in a state of inhibiting positive charges to be rich and uniformly distributing the charges so as to improve the defoaming effect of the surfactant. And, when the surfactant of the present application is applied to a photolithography process, a foaming phenomenon can be suppressed, thereby reducing manufacturing costs and improving productivity.

Referring to fig. 5, fig. 5 is a process flow diagram included in S300 according to an embodiment of the present disclosure. Wherein the step of reacting the second compound, the trimethylamine-containing compound and the second organic solvent in a mixed state at S300 comprises:

s310, providing an aqueous solution containing trimethylamine.

The present embodiments provide an aqueous solution comprising trimethylamine, optionally, one or more of water of trimethylamine, a solution prepared with the trimethylamine salt.

Optionally, in the trimethyl-containing solution, the mass fraction of the trimethyl-containing solute is 25 to 35%. Further optionally, the mass fraction of the trimethyl-containing solute is 28%, 30%, 32%.

S320, heating the aqueous solution containing the trimethylamine to obtain the trimethylamine-containing gas.

In the present embodiment, the aqueous solution containing trimethylamine is changed from liquid to gas by heating. In the present embodiment, the heating temperature and time are not limited. Optionally, the trimethylamine-containing gas comprises one or more of ammonia, other radical-forming organic gases.

S330, mixing and reacting the gas containing the trimethylamine with the second compound and a second organic solvent to obtain a third compound containing the azo group, the trimethylamine and the halogen.

Alternatively, in one embodiment, the second compound and the second organic solvent are mixed, and the gas containing trimethylamine is introduced into the second compound and the second organic solvent to mix and react. In another embodiment, the gas containing trimethylamine is introduced into the second organic solvent, and the second compound is added and mixed for reaction.

In the embodiment, the aqueous solution containing trimethylamine is heated to obtain the gas containing trimethylamine, and the gas containing trimethylamine is mixed with the second compound and the second organic solvent for reaction, so that the compound containing trimethylamine is more fully contacted with the second compound and the second organic solvent, the reaction is easier, and the yield of the surfactant is improved.

Liquid crystal displays are generally composed of three large substrates, namely, an array substrate, a liquid crystal layer and a color film substrate, and at present, both the array substrate and the color film substrate are manufactured by using photoresist, wherein the photoresist is usually positive photoresist (an exposed part generates acid and is dissolved in an alkaline developer), and the photoresist is usually negative photoresist (an exposed part generates a crosslinking reaction and is retained in the alkaline developer). The process route usually comprises multiple routes of cleaning, coating, exposing, developing and post-baking, and both positive photoresist and negative photoresist use abundant surfactant to improve the performances of the photoresist system such as solubility, emulsifying property, dispersibility and the like.

However, the use of surfactants lowers the interfacial energy of the photoresist system leading to the occurrence of blistering. Particularly, the spraying is used for developing in the developing process, so that the foaming phenomenon is easy to occur, foreign matters appear in products, and meanwhile, the filtering filter element for recovering the developing solution is easy to block, the manufacturing cost is improved, and the productivity is reduced. The foaming phenomenon is easy to occur in the developing process, the reason is that the surface tension of the system is large, the interfacial energy is low, and stable bubbles formed by the surfactant, water, oil and air in the photoresist system are not easy to break.

Referring to fig. 6 and 7 together, fig. 6 shows a target pattern which is not prepared by using the photoresist of the present application. FIG. 7 shows a target pattern prepared using a photoresist of the present application. The present application also includes a photoresist comprising a resin, an additive, a solvent, and a surfactant as provided above in the present application.

The photoresist provided by the embodiment is used for a photoetching process. Alternatively, the photoresist may be used in the display field, for example, various physical components such as an array substrate, a color filter substrate, a transistor, a diode, a capacitor, a resistor, and a metal layer are formed on the surface or in the surface layer of the wafer. Optionally, the photoresist comprises a positive photoresist and a negative photoresist.

The photoresist provided by this embodiment mode includes a resin for serving as a base of the photoresist. Alternatively, the resin includes one or more of an alkali-soluble resin, a thermosetting resin, and a photocurable resin. Further optionally, the resin includes a resin matrix, a hydrogen donor agent, a thermal initiator, and a resin solvent. Still further optionally, the resin matrix comprises one or more of methacrylic acid, methyl methacrylate, butyl methacrylate, benzyl methacrylate. The hydrogen donor reagent comprises one or more of dodecanethiol, 1,2-ethanedithiol, 1,6-hexanedithiol and thiol. The thermal initiator includes thiophenol. The resin solvent comprises one or more of propylene glycol methyl ether acetate, diethylene glycol methyl ethyl ether, propylene glycol n-propyl ether, 3-methoxybutyl acetate and polyethylene glycol methyl ether acrylate.

Still further optionally, in the resin, the mass fraction of methacrylic acid is 13% to 18%; the mass fraction of the methyl methacrylate is 17-23%; the mass fraction of the butyl methacrylate is 20-28 percent; the mass fraction of the benzyl methacrylate is 17-23%; the mass fraction of the hydrogen donor reagent is 1-3%; the mass fraction of the thermal initiator is 7-10%; the mass fraction of the resin solvent is 25-40%.

The photoresist provided by the embodiment further comprises an additive and a solvent, wherein the additive can be added according to the functions required by the photoresist. The solvent is used to dissolve the resin, additives, and surfactants. Optionally, the additives include one or more of a defoamer (such as a surfactant herein), an adhesion promoter, allyltriethoxysilane, n-octyltriethoxysilane, allyloxytrimethylsilane. Optionally, the solvent comprises one or more of propylene glycol methyl ether acetate, diethylene glycol methyl ethyl ether, propylene glycol n-propyl ether, 3-methoxybutyl acetate, and polyethylene glycol methyl ether acrylate.

The photoresist provided by this embodiment further includes a surfactant, which is described above in detail and is not described herein again.

Optionally, the photoresist further comprises a dye, a monomer, and a photoinitiator. The dye is used for coloring. Further alternatively, the present embodiment does not limit the color of the dye. The dye includes one or more of a red dye, a blue dye, and a yellow dye. The monomer comprises one or more of polymer monomer, free radical monomer, cationic monomer, methacrylic acid and butyl methacrylate. The photoinitiator comprises one or more of free radical type photoinitiators, cationic photoinitiators, acetophenones, alpha-aminoalkylbenzophenones, benzophenones, benzoins, thioxanthones, anthraquinones, triazines and oximes.

For example: 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-acetophenone, 2,2-dibutoxyacetophenone, 1-hydroxy-cyclohexyl-phenyl ketone, 2-methyl-1- (4-methylthiophenyl) -2-morpholin-1-one, 2-hydroxy-2-methyl-1-phenyl-1-propanone, 2-methyl-1- [4- (methylthio) phenyl ] -2- (4-morpholinyl) -1-propanone, 2-benzyl-2-dimethylamino-1- (4-morpholinylphenyl) -1-butanone, 2-dimethylamino-2- (4-methyl) benzyl-1- [4- (4-morpholinyl) phenyl ] -1-butanone, 2- (dimethylamino) ethyl benzoate, benzophenone, methyl benzophenone, hydroxybenzophenone, 4,4-dimethylaminobenzophenone, 4-bromobenzophenone, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, and the like. As thioxanthones, thioxanthone, 2-chlorothioxanthone, 2-ethylthioxanthone, 2-isopropylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 1-chloroanthraquinone, 2- (4-methoxyphenyl) -4,6-bis (trichloromethyl) -s-triazine, 2- (4-methoxynaphthyl) -4,6-bis (trichloromethyl) -s-triazine, 2- (4-ethoxynaphthyl) -4,6-bis (trichloromethyl) -s-triazine, 2- (4-ethoxycarbonylnaphthyl) -4,6-bis (trichloromethyl) -s-triazine, 1- [ 9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl ] -1- (O-acetyl) phenylketoxime, 1- [ 2- (3432-benzoyloxy) -s-triazine, and acetyl-phenyl-oxime are cited.

Still further optionally, in the photoresist, a mass fraction of resin is 9-%11%; the mass fraction of the dye is 5-8%; the mass fraction of the monomer is 5.8-11%; the mass fraction of the photoinitiator is 0.1-0.2%; the mass fraction of the additive is 0.1-0.2%; the mass fraction of the solvent is 67-80%.

The photoresist provided by the embodiment can be converted from a trans-structure to a cis-structure by adopting the surfactant provided by the application, and the surfactant can be in a state of inhibiting positive charges to be rich and uniformly distributing the charges, so that bubbles are not easily formed, and the formed bubbles are easily destroyed, thereby improving the defoaming effect of the surfactant. Therefore, when the photoresist of the present embodiment is applied to a photolithography process, a bubble phenomenon can be suppressed, thereby reducing a manufacturing cost and improving productivity.

And the surfactant of the photoresist comprises an ester group containing halogen, so that the surfactant is in a state of abundant positive charge and uniform charge distribution, and the defoaming effect of the surfactant is further improved.

In one embodiment, the surfactant is present in the photoresist in an amount of 0.1% to 2% by mass.

Optionally, when the photoresist is a negative photoresist, the surfactant has a mass fraction of 1% to 2%. Further optionally, the mass fraction of the surfactant is 1.4%, 1.6%, 1.8%.

Optionally, when the photoresist is a positive photoresist, the mass fraction of the surfactant is 0.1% to 1%. Further optionally, the surfactant is present in an amount of 0.4%, 0.6%, 0.8% by weight.

The mass fraction of the surfactant in the photoresist is 0.1-2%, so that the surfactant can be ensured to play a role in inhibiting the bubble phenomenon; and the surfactant can improve the performances of solubilization, emulsification, dispersibility and the like of a photoresist system in the photoresist. If the mass fraction of the surfactant in the photoresist is less than 0.1%, the surfactant cannot ensure that the surfactant can improve the performances such as the solubility, emulsifying property and dispersibility of a photoresist system in the photoresist, and cannot play a role in inhibiting the bubble phenomenon because the amount of the surfactant is small; if the mass fraction of the surfactant in the photoresist is more than 2%, the cost is increased, and the excessive amount of the surfactant affects other substances of the photoresist, thereby reducing the property of the surfactant in the photoresist for improving the solubility, emulsifying property and dispersibility of the photoresist system.

As shown in fig. 6 and 7, it can be seen from fig. 6 that the target pattern prepared without using the organic formulation prepared by the photoresist of the present application has uneven edges and has a severe warpage phenomenon, which may also be referred to as a Peeling phenomenon. The Peeling phenomenon refers to the warping of the edge of the photoresist, i.e., the separation between the photoresist and the silicon wafer. As can be seen from FIG. 7, the edges of the target pattern prepared by using the photoresist of the present application are very uniform, and the Peeling phenomenon of the organic film layer is effectively improved. This is because the surfactant in the photoresist can suppress the bubble phenomenon, reducing the chance of the target pattern edge being misaligned due to bubble generation and disappearance. The target pattern may be referred to as a Mark pattern.

In the embodiment, a surfactant is used to prevent the development process from foaming (isomerization is performed in the exposure process from trans-isomerization to cis-form, and the steric hindrance effect, interaction and interface energy of the cis-form structure greatly hinder the formation of bubbles in the photoresist) without using an external additive reagent, so that the photoresist forms a dense film layer, and the Peeling phenomenon of the photoresist is effectively improved.

Alternatively, in one embodiment, there is provided a method of manufacturing a negative photoresist, including: alkali soluble resin, dye, monomer, photoinitiator, functional additive and solvent are mixed according to a preset proportion to prepare the negative photoresist.

Specifically, the alkali-soluble resin of the present embodiment can be prepared by mixing and sufficiently stirring a resin matrix, a hydrogen donor reagent, an excess amount of a thermal initiator, and a resin solvent according to a predetermined ratio.

Firstly, 13-18% of methacrylic acid, 17-23% of methyl methacrylate, 20-28% of butyl methacrylate, 17-23% of benzyl methacrylate, 1-3% of hydrogen donor reagent, 7-10% of thermal initiator and 25-40% of resin solvent are mixed according to mass percentage to prepare the alkali soluble resin.

Then, mixing the target alkali-soluble resin with the photoresist base material in a predetermined ratio, comprising: according to the mass percentage, 9 to 11 percent of target alkali soluble resin, 5 to 8 percent of dye, 5.8 to 11 percent of monomer, 0.1 to 0.2 percent of photoinitiator, 1 to 2 percent of surfactant, 0.1 to 0.2 percent of functional additive and 67 to 80 percent of solvent are mixed to prepare the negative photoresist.

The application also provides a photoetching method. Referring to fig. 8, fig. 8 is a process flow chart of a manufacturing method of a photolithography method according to an embodiment of the present application. The embodiment provides a photolithography method including S10, S20, S30, S40, and S50. The details of S10, S20, S30, S40, and S50 are as follows.

S10, providing a piece to be photoetched and the photoresist provided by the application.

And S20, coating the photoresist on the piece to be photoetched.

In one embodiment, the photoresist is coated on the piece to be photoetched, and the photoresist coated on the piece to be photoetched is dried for the first time. It should be noted that the first drying may also be understood as a pre-drying.

Optionally, in the first drying process, the pre-drying temperature is 80 ℃ to 120 ℃, and the pre-drying time is 80s to 120s. Further optionally, the pre-baking temperature is 90 ℃, or 100 ℃, or 110 ℃; the prebaking time is 90s, 100s or 110s.

Wherein the photoresist is pre-baked for 80-120 s at 80-120 ℃ to form a film layer with the thickness of 0.8-1.2 μm. Alternatively, the thickness of the formed layer is 0.9 μm, or 1.0 μm, or 1.1 μm. Optionally, the piece to be lithographed is a glass substrate.

And S30, exposing the photoresist coated on the piece to be photoetched.

In one embodiment, a mask is disposed on a side of the photoresist opposite to the member to be etched, and the photoresist coated on the member to be etched is exposed.

Optionally, during the exposure, the exposure wavelength is 350nm-450nm, and the exposure energy is 35mJ/cm ² -60mJ/cm ² 。

Further optionally, the exposure wavelength is 365nm, or 380nm, or 400nm, or 420nm, or 445nm; the exposure energy is 40mJ/cm ² Or 45mJ/cm ² Or 50mJ/cm ² Or 55mJ/cm ² 。

Wherein the distance between the light source and the piece to be photoetched is 220-280 μm. Optionally, the distance between the light source and the piece to be lithographed is 240 μm, or 250 μm, or 260 μm.

In other words, a mask is arranged on the photoresist film layer and is exposed by a UV-LED light source with the wavelength of 350nm-450nm, and the UV irradiation energy of the light source is 35mJ/cm ² -60mJ/cm ² Wherein the distance between the light source and the substrate is 220-280 μm. The substrate is referred to herein as the article to be lithographed.

S40, pretreating the photoresist coated on the piece to be subjected to photoetching to enable the surfactant in the photoresist to meet a preset condition so as to enable the surfactant to be converted from the trans-structure to the cis-structure.

And S50, developing the pretreated photoresist.

In one embodiment, the mask is removed, the pretreated photoresist is developed, and the developed photoresist is dried for the second time to obtain the target pattern. The second drying may be understood as a post-development drying.

Optionally, in the developing process, the developing temperature is 20-23 ℃ and the developing time is 30-60s. In the second drying process, the second drying temperature is 200-230 ℃, and the second drying time is 30-40min.

Further optionally, the development temperature is 21 ℃, or 22 ℃; the development time was 40s, or 45s, or 50s. The second drying temperature is 210 ℃ or 220 ℃; the second drying time is 32min, 35min or 38min.

In other words, the mask is taken off, the exposed photoresist film layer is developed by adopting a developing solution at the temperature of 20-23 ℃ for 30-60s, and is post-baked at the temperature of 200-230 ℃ for 30-40min to obtain the required pattern. Optionally, the developer is an alkaline developer.

In this embodiment, the order of performing the pretreatment and the exposure of the photoresist is not limited. In one embodiment, the photoresist can be pre-treated prior to exposing the photoresist. In another embodiment, the photoresist can be exposed prior to pretreatment of the photoresist. In yet another embodiment, the photoresist can be exposed and pretreated simultaneously. In other words, the photoresist is only required to be pretreated before being developed so that the surfactant in the photoresist satisfies a predetermined condition.

The piece to be photoetched is used for photoetching the piece to be photoetched. The photoresist is used to coat one side of the photoresist. The photoresist is described in detail above, and is not described in detail herein.

Specifically, in one embodiment, the process of patterning the photoresist is: in the exposure stage, the photoresist is irradiated by ultraviolet light, so that a photoinitiator in the photoresist generates free radicals to promote a crosslinking reaction of monomers or resins in a light receiving area to be reserved after a subsequent developing process, and areas which are not irradiated by the ultraviolet light are dissolved by a developing solution in the subsequent developing process, so that a required photoresist pattern is formed. In other words, the photoresist is exposed to light to cure the photoresist, thereby forming a desired photoresist pattern.

The photoetching method provided by the embodiment is simple in process and high in operability. Through adopting the above-mentioned photoresist that provides of this application, and before carrying out the development to the photoresist, make the surfactant active of photoresist satisfy the preset condition to make surfactant active convert the cis-form structure from the trans-form structure, neither easily form the bubble, make the bubble after forming easily destroyed again, with the defoaming effect who improves surfactant active, restrain the bubbling phenomenon, thereby reduce manufacturing cost, improve the productivity.

And the surfactant of the photoresist comprises an ester group containing halogen, so that the surfactant is in a state of abundant positive charges and uniform charge distribution, and the defoaming effect of the surfactant is further improved.

Optionally, before the step of applying the photoresist to the piece to be photoetched, the method further comprises: and cleaning the piece to be subjected to photoetching, thereby removing foreign matters, dust and the like on the piece to be subjected to photoetching, and further coating the photoresist on the clean piece to be subjected to photoetching.

Optionally, after the step of developing the photoresist coated on the pretreated workpiece to be subjected to photolithography, the method further includes: baking the photoresist coated on the exposed piece to be subjected to photoresist coating, so as to shape the photoresist, volatilize solvent components in the photoresist, reduce the film stress of the photoresist and enhance the adhesiveness of the photoresist on the substrate.

Referring to fig. 9, fig. 9 is a process flow diagram included in S30 and S40 according to an embodiment of the present disclosure. Wherein in S30, the pre-treatment comprises exposure, and the photoresist coated on the piece to be photoetched is exposed.

S40, pretreating the photoresist coated on the piece to be photoetched to enable the surfactant in the photoresist to meet a preset condition so as to enable the surfactant to be converted from the trans-structure into the cis-junction, wherein the step comprises the following steps:

s31, exposing the photoresist coated on the piece to be photoetched, curing the photoresist, and enabling the surfactant in the photoresist to meet a preset condition, so that the surfactant is converted from the trans-structure to the cis-structure.

In the exposure process of the photoetching method, the photoresist can be exposed to realize the curing of the photoresist, the effect which the exposure process needs to achieve is realized, and the surfactant can meet the preset condition, so that the surfactant is converted from a trans-structure to a cis-structure, the defoaming effect of the surfactant is improved, and the foaming phenomenon is inhibited. The method combines the exposure process and the surfactant pretreatment, thereby simplifying the steps of the photoetching method, reducing the manufacturing cost and improving the productivity.

Specifically, when the surfactant is subjected to exposure processing and then is isomerized from a trans form to a cis form, the interfacial energy, the steric hindrance effect, the interaction enthalpy and the like of the surfactant are not easily increased, and the surfactant is compounded with other surfactants, so that the formation of bubbles in the surfactant is prevented, the formation of bubbles in the development processing is inhibited, a compact photoresist film is formed, and the photoresist Peeling is effectively prevented.

Optionally, when the preset condition is exposure, the wavelength of the exposure ranges from 350nm to 450nm, and the exposure time ranges from 1s to 5s.

At the moment, the photosensitive surfactant is similar to a photosensitive switch, and when the photoresist is not exposed, the photosensitive molecules of the azo structure can be compounded with other surfactants in a photoresist system to form a mixed type surfactant, and then the mixed type surfactant, the developing solution and air form bubbles. However, when the photoresist is exposed to light, the azo photosensitive surfactant isomerizes to increase its steric hindrance, interfacial energy, and intermolecular interactions, thereby preventing the surfactant molecules in the photoresist from forming bubbles.

Therefore, the embodiment uses the photosensitive molecules to prevent the foaming of the development process, effectively improve the photoresist Peeling and improve the edge trim of the organic film layer without using an external additive reagent.

Optionally, in an embodiment, the photoresist is coated on the to-be-etched piece, and the photoresist coated on the to-be-etched piece is dried for the first time. Wherein, in the first drying process, the pre-drying temperature is 80-120 ℃, and the pre-drying time is 80-120 s.

Then, arranging a mask plate on one side of the photoresist, which is far away from the piece to be photoetched, and exposing the photoresist coated on the piece to be photoetched. Wherein, in the exposure process, the exposure wavelength is 350nm-450nm, and the exposure energy is 35mJ/cm ² -60mJ/cm ² And the distance between the light source and the piece to be photoetched is 220-280 μm.

And then, removing the mask, developing the photoresist, and drying the developed photoresist for the second time to obtain a target pattern. Wherein, in the developing process, the developing temperature is 20-23 ℃ and the developing time is 30-60s. In the secondary drying process, the secondary drying temperature is 200-230 ℃, and the secondary drying time is 30-40min.

In the present embodiment, since the photoresist provided above is used, the photoresist film is subjected to defoaming treatment during exposure, that is, the photoresist is pretreated, so that the surfactant is isomerized from a trans-form to a cis-form after exposure, thereby improving the defoaming effect of the surfactant and suppressing the foaming phenomenon.

Because the defoaming treatment is carried out on the photoresist film layer, the exposure effect is better, and the development is more convenient to operate. Specifically, the temperature of the developing treatment can be lower, and the time is shorter, so that the previous developing effect can be achieved. For example, development is carried out at 20 ℃ to 23 ℃ for 30s to 60s. Particularly, as the defoaming treatment is carried out on the photoresist film layer, the photoresist film layer can be removed more easily after exposure, and the photoresist film layer can be developed for 30s at a lower temperature of 20 ℃, so that the exposed area can be completely etched without burrs. The burr here can also be understood as a jagged photoresist.

And in the second drying, because the non-exposure area has no bubbles, the film layer is smoother and the gap is smaller, the second drying at lower temperature (200-230 ℃) can be adopted, and the time duration is 30-40min. The photoresist film layer is more compact and more stable, the photoetching pattern is clearer, the effect is better and the subsequent processing is more facilitated by mainly utilizing the lower temperature, such as 200 ℃ and low-temperature long baking. The non-exposure area refers to the part of the photoresist which is shielded by the mask and is not exposed.

In conclusion, due to the adoption of the photoresist provided by the application, the defoaming effect can be achieved in the exposure process. In the embodiment, parameters in the subsequent developing process and the subsequent baking process are further improved by combining defoaming, so that the photoetching effect is better.

In order to make the above-mentioned details and operations of the present invention clearly understood by those skilled in the art and to make the examples of the present invention remarkably manifest the advanced performance of the preparation method of the surfactant, the above-mentioned technical solutions are exemplified by a plurality of examples below.

Example 1:

reaction 1: weighing 5 parts of p-butyl azophenol by mass fraction, adding the p-butyl azophenol into a 250ml round-bottom flask, and adding 50 parts of absolute ethyl alcohol (CH) ₃ CH ₂ OH), weighing 1,6-dibromohexane (C) ₆ H ₁₂ Br ₂ ) 10 parts of anhydrous ethanol mixed solution and 1 part of sodium hydroxide (NaOH) are prepared into 34 parts of anhydrous ethanol mixed solution, the mixed solution is dropwise added into a round-bottom flask at 78 ℃ and heated and refluxed for 8 hours, a filtered product is kept still for 24 hours after the reaction is finished to obtain an orange yellow solid, and the yellow product is repeatedly washed by the anhydrous ethanol and deionized water and then dried in a vacuum oven at 60 ℃ for 12 hours to obtain the product 4-butylazobenzene-4- (oxy) bromohexane. A specific reaction 1 is shown below:

reaction 2: weighing 2 parts of the compound 4-butylazobenzene-4- (oxy) bromohexane obtained in the above reaction 1, dissolving in 48 parts of Tetrahydrofuran (THF) to prepare a solution, and heating 30% by mass of trimethyl azobenzeneAqueous amine solution (C) ₃ H ₉ And N) introducing the prepared gas into the solution, keeping stirring and continuously reacting for 1 hour, standing the solution after reaction for 48 hours at room temperature, repeatedly leaching the filter cake after rotary evaporation by tetrahydrofuran, drying the solid product in a vacuum oven at 60 ℃ for 12 hours, and then continuously recrystallizing twice by using absolute ethyl alcohol to obtain the product 4-butylazobenzene-4- (hexyloxy) trimethyl ammonium bromide. A specific reaction 2 is shown below:

reaction 3: 1 part of 4-butylazobenzene-4- (hexyloxy) trimethylammonium bromide obtained in the above reaction 2 was weighed in dichloromethane (CH) ₂ Cl ₂ ) To prepare a solution, 2 parts of sodium trifluoroacetate (CF) are added ₃ COONa) is stirred for continuous reaction, and the surfactant [ BAZOC ] is obtained after solid-liquid separation ₆ TMA]TfO. A specific reaction 3 is shown below:

example 2:

reaction 1: weighing 3 parts of p-butyl azophenol by mass fraction, adding the p-butyl azophenol into a 250ml round-bottom flask, and adding 50 parts of absolute ethyl alcohol (CH) ₃ CH ₂ OH), weighing 1,6-dibromohexane (C) ₆ H ₁₂ Br ₂ ) 5 parts of anhydrous ethanol mixed solution and 1 part of sodium hydroxide (NaOH) are prepared into 34 parts of anhydrous ethanol mixed solution, the mixed solution is dropwise added into a round-bottom flask at 70 ℃ and heated and refluxed for 9 hours, a filtered product is kept still for 24 hours after the reaction is finished to obtain an orange yellow solid, and the yellow product is repeatedly washed by the anhydrous ethanol and deionized water and then dried in a vacuum oven at 60 ℃ for 12 hours to obtain the product 4-butylazobenzene-4- (oxy) bromohexane.

Reaction 2: 1 part of 4-butylazobenzene-4- (oxy) bromohexane, the compound obtained in the above reaction 1, was weighed and dissolved in 40 parts of Tetrahydrofuran (THF) to prepare a solution, and then 25% by mass fraction of tris (tetrahydrofuran) was heatedMethylamine aqueous solution (C) ₃ H ₉ And N) introducing the prepared gas into the solution, keeping stirring and continuously reacting for 1.5 hours, standing the solution after reaction for 48 hours at room temperature, repeatedly leaching a filter cake after rotary evaporation by using tetrahydrofuran, drying a solid product in a vacuum oven at 60 ℃ for 12 hours, and then continuously recrystallizing twice by using absolute ethyl alcohol to obtain a product, namely 4-butylazobenzene-4- (hexyloxy) trimethyl ammonium bromide.

Reaction 3: 1 part of 4-butylazobenzene-4- (hexyloxy) trimethylammonium bromide obtained in the above reaction 2 was weighed in dichloromethane (CH) ₂ Cl ₂ ) To prepare a solution, 1 part of sodium trifluoroacetate (CF) is added ₃ COONa) is stirred for continuous reaction, and the surfactant [ BAZOC ] is obtained after solid-liquid separation ₆ TMA]TfO。

Example 3:

reaction 1: weighing 4 parts of p-butyl azophenol by mass fraction, adding the p-butyl azophenol into a 250ml round-bottom flask, and adding 50 parts of absolute ethyl alcohol (CH) ₃ CH ₂ OH), weighing 1,6-dibromohexane (C) ₆ H ₁₂ Br ₂ ) 15 parts of anhydrous ethanol mixed solution and 1 part of sodium hydroxide (NaOH) are prepared into 34 parts of anhydrous ethanol mixed solution, the mixed solution is dropwise added into a round-bottom flask at 90 ℃ and heated and refluxed for 7 hours, a filtered product is kept still for 24 hours after the reaction is finished to obtain an orange yellow solid, and the yellow product is repeatedly washed by the anhydrous ethanol and deionized water and then dried in a vacuum oven at 60 ℃ for 12 hours to obtain the product 4-butylazobenzene-4- (oxy) bromohexane.

Reaction 2: 3 parts of 4-butylazobenzene-4- (oxy) bromohexane, the compound obtained in the above reaction 1, was weighed and dissolved in 60 parts of Tetrahydrofuran (THF) to prepare a solution, and an aqueous solution of trimethylamine (C) having a mass fraction of 35% was heated ₃ H ₉ And N) introducing the prepared gas into the solution, keeping stirring and continuously reacting for 0.5 hour, standing the solution after reaction for 48 hours at room temperature, repeatedly leaching a filter cake after rotary evaporation by using tetrahydrofuran, drying a solid product in a vacuum oven at 60 ℃ for 12 hours, and then continuously recrystallizing twice by using absolute ethyl alcohol to obtain a product, namely 4-butylazobenzene-4- (hexyloxy) trimethyl ammonium bromide.

Reaction 3: weighing 1 part of4-butylazobenzene-4- (hexyloxy) trimethylammonium bromide obtained in the above reaction 2 in methylene Chloride (CH) ₂ Cl ₂ ) To prepare a solution, 3 parts of sodium trifluoroacetate (CF) are added ₃ COONa) is stirred for continuous reaction, and the surfactant [ BAZOC ] is obtained after solid-liquid separation ₆ TMA]TfO。

The foregoing detailed description has provided for the embodiments of the present application, and the principles and embodiments of the present application have been presented herein for purposes of illustration and description only and to facilitate understanding of the methods and their core concepts; meanwhile, for a person skilled in the art, according to the idea of the present application, the specific implementation manner and the application scope may be changed, and in summary, the content of the present specification should not be construed as a limitation to the present application.

Claims

1. A surfactant, comprising at least one azo group, wherein one nitrogen element in the azo group is connected with a first group, and the other nitrogen element is connected with a second group, the surfactant has a trans structure and a cis structure, and when the surfactant meets a preset condition, the surfactant is converted from the trans structure to the cis structure;

wherein the trans structure is:

the cis structure is:

2. The surfactant of claim 1, wherein said halogen-containing ester group comprises a trihalo-carbethoxy group, or a dihalo-carbethoxy group, or a monohalo-carbethoxy group; wherein the halogen comprises one or more of fluorine, chlorine, bromine, and iodine.

3. The surfactant of claim 1, wherein the predetermined condition comprises at least one of:

exposing the surfactant by adopting ultraviolet light of 350nm-450 nm;

the exposure time is 1s-5s.

4. A method for preparing a surfactant, comprising:

5. The method according to claim 4, wherein the step of reacting the second compound, the trimethylamine-containing compound and the second organic solvent in combination comprises:

providing an aqueous solution comprising trimethylamine;

6. The method according to claim 4, wherein the molar ratio of the third compound to the compound having a halogen-containing ester group is 1: (1-3).

7. A photoresist comprising a resin, an additive, a solvent, and the surfactant of any one of claims 1-3.

8. The photoresist of claim 7, wherein the surfactant is present in the photoresist at a mass fraction of 0.1 to 2%.

9. A method of lithography, comprising:

providing a piece to be photoetched and a photoresist according to any one of claims 7 to 8;

coating the photoresist on the piece to be photoetched;

exposing the photoresist coated on the piece to be photoetched;

pretreating the photoresist coated on the piece to be subjected to photoresist, so that the surfactant in the photoresist meets a preset condition, and converting the surfactant from the trans-structure to the cis-structure;

and developing the pretreated photoresist.

10. The lithography method according to claim 9, wherein said pretreatment includes exposure, said exposure being performed on said resist coated on said member to be photoetched;