A positive photosensitive resin composition with chemical amplification, a method for preparing the same, a microlens, and a method for preparing the same

Abstract

This invention provides a chemically amplified positive photosensitive resin composition and its preparation method, as well as a microlens and its preparation method. The chemically amplified positive photosensitive resin composition comprises the following components: a first resin A, a second resin B, a photoacid generator C, a quencher D, and a solvent E. By designing the specific composition of the chemically amplified positive photosensitive resin composition, and through the synergistic effect of the first resin A and the second resin B with specific structures, this invention effectively reduces the Tg and reflow temperature of the first resin A and the second resin B, thereby lowering the reflow temperature for preparing microlenses using this chemically amplified positive photosensitive resin composition. This achieves the goal of preparing microlenses at low-temperature reflow (<100℃) and improves the contrast, resolution, and etching resistance of the microlenses.

Description

Technical Field

[0001] This invention belongs to the technical field of chemically amplified positive photosensitive resin composition materials, specifically relating to a chemically amplified positive photosensitive resin composition and its preparation method, and a microlens and its preparation method. Background Technology

[0002] Microlenses, as a key optical structure in Organic Light-Emitting Diodes (OLEDs), consist of an array of numerous micrometer-sized lens units. By controlling the refraction angle of the light path, they suppress total internal reflection losses and achieve focusing, diffusion, or homogenization of light waves. As OLED technology advances towards higher precision, the application of microlens materials places higher demands on photosensitive resin compositions, requiring them to form precise microlens patterns. Because the organic light-emitting layer of OLEDs is sensitive to high temperatures, traditional microlens processes using 150-250°C high-temperature reflow processes lead to brightness decay and device lifespan degradation. Therefore, low-temperature processing techniques (<100°C) are required when microlenses are used in OLED device manufacturing.

[0003] In existing technologies, reflow etching is a commonly used technique for fabricating microlenses. The core principle of this method is to utilize thermally induced flow and surface tension to transform the photolithographically formed rectangular cross-section resin pattern into the desired lens shape. Etching is another microlens fabrication technique. This method first deposits a microlens resin layer on a color filter layer. Then, using a photosensitive resin composition and employing exposure, development, and heat flow steps, a hemispherical lens pattern is formed on this resin layer. Subsequently, this lens pattern is used as an etching mask to etch the underlying microlens resin layer, thereby accurately transferring the lens shape from the mask into the resin layer, completing the microlens fabrication. When using etching, to ensure good transfer of the microlens pattern shape, the resin layer must be able to form a microlens pattern with a correspondingly high etching rate with the lens material layer.

[0004] However, traditional photosensitive resin compositions for preparing microlenses often suffer from problems such as excessively high reflow temperatures, insufficient resolution, and low X-ray sensitivity. Among these, the glass transition temperature (Tg) of the resin is one of the key factors determining the reflow temperature. Furthermore, the resin's Tg is influenced by various factors, including molecular weight, molecular weight distribution (Mw / Mn), the type of photoacid-generating agent, the role of additives, and the amount of residual solvent. Notably, the Tg of traditional methyl-type phenolic resins is typically slightly higher than that of phenolic-type phenolic resins, which is closely related to the steric hindrance effect of the methyl substituents and changes in intermolecular forces. The combined effect of these factors ultimately determines the thermal properties of the photosensitive resin composition, thus affecting its reflow behavior in photolithography processes.

[0005] Based on the above, how to provide a positive photosensitive resin composition that can achieve low-temperature reflux (<100℃), high resolution and etch resistance for chemical amplification, as well as a high-performance microlens, has become an urgent technical problem to be solved. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the present invention aims to provide a chemically amplified positive photosensitive resin composition and its preparation method, as well as a microlens and its preparation method. By designing the specific composition of the chemically amplified positive photosensitive resin composition, and through the synergistic effect of a first resin A and a second resin B with specific structures, the present invention effectively reduces the Tg and reflow temperature of the first resin A and the second resin B, thereby lowering the reflow temperature for preparing microlenses using this chemically amplified positive photosensitive resin composition. This achieves the goal of preparing microlenses at low-temperature reflow (<100℃) and improves the specific gravity, resolution, and etching resistance of the microlenses.

[0007] To achieve this objective, the present invention adopts the following technical solution: In a first aspect, the present invention provides a chemically amplified positive photosensitive resin composition, the chemically amplified positive photosensitive resin composition comprising the following components: a first resin A, a second resin B, a photoacid generator C, a quencher D, and a solvent E. The first resin A includes structural units having the following structural units: a1 and a2. ; in, Indicates the connection site; , Each can independently represent a hydrogen atom or a C1-C6 alkyl group; , Each of these terms independently represents a C1-C6 alkyl or C1-C6 alkoxy group; , , Each of them independently represents a hydrogen atom or a C1-C12 alkyl group; m1 and m3 each independently represent integers from 0 to 4, and m2 represents integers from 1 to 5, and 1≤m1+m2≤5; The second resin B includes structural units having the following structural units: formula b1 and formula b2. ; in, Indicates the connection site; R b1 Indicates a C1-C6 alkyl or C1-C6 alkoxy group; R b2 R b3 R b4Each can independently represent a hydrogen atom or a C1-C12 alkyl group; n1 and n3 can independently represent integers from 0 to 4, n2 can represent integers from 1 to 4, and 1≤n1+n2≤4; The mass ratio of the first resin A to the second resin B is 60:40-80:20.

[0008] This invention designs the specific composition of a chemically amplified positive photosensitive resin composition. Through the synergistic effect of the first resin A and the second resin B containing acetal-type acid-instable group structural units (structural unit a1 in the first resin A and structural unit b1 in the second resin A), the Tg and reflux temperature of the first resin A and the second resin B are effectively reduced. This, in turn, lowers the reflux temperature for preparing microlenses using this chemically amplified positive photosensitive resin composition, achieving the goal of preparing microlenses at low-temperature reflux (≤100℃) and improving the specific gravity, resolution, and etching resistance of the microlenses.

[0009] Meanwhile, by controlling the mass ratio of the first resin A and the second resin B in the chemically amplified positive photosensitive resin composition within a specific range, this invention further improves the overall performance of the chemically amplified positive photosensitive resin composition and the microlens. If the mass ratio of the first resin A and the second resin B in the chemically amplified positive photosensitive resin composition is too small, i.e., the amount of the first resin A is too small, the final microlens will have poor contrast; if the mass ratio of the first resin A and the second resin B in the chemically amplified positive photosensitive resin composition is too large, i.e., the amount of the first resin A is too large, the final microlens will have poor pattern reflow properties.

[0010] In this invention, C1-C6 can be C1, C2, C3, C4, C5 or C6.

[0011] C1-C12 can be C1, C2, C3, C4, C5, C6, C7, C8, C9, C10, C11 or C12.

[0012] m1 and m3 each independently represent integers from 0 to 4 (e.g., 0, 1, 2, 3, or 4), and m2 represents integers from 1 to 5 (e.g., 1, 2, 3, 4, or 5), where 1 ≤ m1 + m2 ≤ 5. It should be noted that when m1 represents integers from 2 to 4, equation a1 contains 2 to 4 integers. , They can be the same or different from each other.

[0013] n1 represents an integer from 0 to 4 (e.g., 0, 1, 2, 3, or 4), and n2 represents an integer from 1 to 4 (e.g., 1, 2, 3, or 4), where 1 ≤ n1 + n2 ≤ 4. It should be noted that when n1 represents an integer from 2 to 4, equation b1 contains 2-4 R's.b1 R b1 They can be the same or different from each other.

[0014] In this invention, the C1-C6 alkoxy groups include C1-C6 straight-chain or branched alkoxy groups and C3-C6 cycloalkoxy groups.

[0015] In this invention, C1-C6 straight-chain or branched alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, n-hexyl, etc. C3-C6 cycloalkyl groups include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, etc. C1-C12 straight-chain or branched alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-nonyl, or n-decyl, etc. C3-C12 cycloalkyl groups include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, adamantyl, etc.

[0016] In this invention, the mass ratio of the first resin A and the second resin B is 60:40-80:20, for example, it can be 60:40, 63:37, 65:35, 68:32, 70:30, 72:28, 75:25, 77:23 or 80:20, etc.

[0017] The following are preferred technical solutions of the present invention, but are not intended to limit the technical solutions provided by the present invention. The purpose and beneficial effects of the present invention can be better achieved and realized through the following preferred technical solutions.

[0018] Preferably, m1 and m3 each independently represent 0.

[0019] Preferably, m2 represents 1.

[0020] Preferably, the first resin A comprises resin A1 having the following structural units: ; In resin A1, the ratio of x to y is 55:45-80:20, for example, it can be 55:45, 60:40, 65:35, 70:30, 75:25 or 80:20, etc.

[0021] Preferably, the weight-average molecular weight of the first resin A is 5000-15000, for example, it can be 5000, 6000, 7000, 8000, 9000, 10000, 11000, 12000, 13000, 14000 or 15000.

[0022] Preferably, n1 and n3 each independently represent 0.

[0023] Preferably, n2 represents 1.

[0024] Preferably, the second resin B comprises resin B1 having the following structural unit: ; In resin B1, the ratio of p to q is 55:45-80:20, for example, it can be 55:45, 60:40, 65:35, 70:30, 75:25 or 80:20, etc.

[0025] Preferably, the weight-average molecular weight of the second resin B is 2000-7000, for example, it can be 2000, 2500, 3000, 3500, 4000, 4500, 5000, 5500, 6000, 6500 or 7000.

[0026] Preferably, the PDI (molecular weight distribution index) of the second resin B is 2.5-5.0, for example, it can be 2.5, 2.6, 2.8, 3.0, 3.2, 3.4, 3.6, 3.8, 4.0, 4.2, 4.4, 4.6, 4.8 or 5.0.

[0027] Preferably, with the sum of the mass parts of the first resin A and the second resin B being 100 parts, the mass part of the photoacid-generating agent C is 0.5 parts to 30 parts (for example, it can be 0.5 parts, 1 part, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 8 parts, 10 parts, 12 parts, 15 parts, 18 parts, 20 parts, 22 parts, 25 parts, 27 parts, or 30 parts, etc.), preferably 1 part to 20 parts, and more preferably 1 part to 5 parts.

[0028] This invention does not impose any special restrictions on the specific selection of the photoacid-generating agent C. All commonly used photoacid-generating agents C in the art are applicable, including nonionic and / or ionic photoacid-generating agents. Furthermore, this invention does not impose any special restrictions on the specific selection of the nonionic photoacid-generating agent. All commonly used nonionic photoacid-generating agents in the art are applicable, including but not limited to: organohalides, sulfonate photoacid-generating agents (e.g., 2-nitrobenzoyl ester, aromatic sulfonates, oxime sulfonates, N-sulfonyloxyimide, sulfonyloxyketone, diazonoquinone-4-sulfonate), and sulfone photoacid-generating agents (e.g., disulfone, ketone sulfone, sulfonyldiazomethane), etc. Meanwhile, this invention does not impose any special restrictions on the specific selection of the ionic photoacid-generating agent. All commonly used ionic photoacid-generating agents in the art are applicable, including but not limited to: ononium salts containing ononium cations (e.g., diazonium salts, phosphonium salts, sulfonium salts, iodoonium salts). Examples of onium salt anions include sulfonate anions, sulfonylimide anions, and sulfonylmethyl anions.

[0029] Preferably, the photoacid-generating agent C comprises , , , , Any one or at least two of them.

[0030] In this invention, the chemically amplified positive photosensitive resin composition may contain one photoacid generator C alone, or it may contain two or more photoacid generator Cs.

[0031] Preferably, based on a total mass fraction of 100 parts for the first resin A and the second resin B, the mass fraction of the quenching agent D is 0.0001 to 5 parts (e.g., 0.0001, 0.0005, 0.001, 0.005, 0.01, 0.05, 0.1, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, or 5 parts, etc.), more preferably 0.0001 to 4 parts, and even more preferably 0.001 to 3 parts.

[0032] Preferably, based on a total mass fraction of 100 parts for the first resin A and the second resin B, the mass fraction of the quenching agent D is 0.01 to 1 part (e.g., 0.01, 0.02, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1 part, etc.), and more preferably 0.1 to 0.7 parts.

[0033] In this invention, there are no special restrictions on the specific selection of the quencher D; commonly used quenchers D in the art are applicable, including but not limited to: basic nitrogen-containing organic compounds. Examples of basic nitrogen-containing organic compounds include amines and ammonium salts. The amines include aliphatic amines (primary, secondary, and tertiary amines), aromatic amines, etc. Specifically, the quencher D includes, but is not limited to: , , .

[0034] This invention does not impose any special restrictions on the specific selection of solvent E, such as propylene glycol monomethyl ether acetate, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol propyl ether acetate, propylene glycol monobutyl ether, propylene glycol monobutyl ether acetate, toluene, xylene, methyl ethyl ketone, cyclopentanone, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxylate, ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutyrate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate, methyl pyruvate, ethyl acetate, butyl acetate, ethyl lactate, butyl lactate, 2-heptanone, γ-butyrolactone, etc. In this invention, the solvents described above can be used alone or in combination of two or more.

[0035] Preferably, with the sum of the mass parts of the first resin A and the second resin B being 100 parts, the mass part of the solvent E is 200-400 parts (for example, it can be 200 parts, 220 parts, 240 parts, 260 parts, 280 parts, 300 parts, 320 parts, 340 parts, 360 parts, 380 parts or 400 parts, etc.), preferably 300-400 parts.

[0036] Preferably, the solid content of the chemically amplified positive photosensitive resin composition is 20%-30%, for example, it can be 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29% or 30%, etc.

[0037] Preferably, the chemically amplified positive photosensitive resin composition further includes surfactant F.

[0038] In this invention, there are no special restrictions on the specific selection of surfactant F, as long as it can improve the coating properties, defoaming properties, and uniform coating of the chemically scaled-up positive photosensitive resin composition. Exemplary examples include, but are not limited to: surfactants having fluorine atoms, surfactants having both silicon and fluorine atoms, polyether-modified siloxane compounds, and other siloxane compounds. The surfactants include, but are not limited to, one or more of BYK-310, DFX-18, NEOS212M, and NEOS215M.

[0039] Preferably, based on the mass percentage of the solid component in the chemically amplified positive photosensitive resin composition being 100%, the mass percentage of the surfactant F is ≤1% (e.g., it can be 0.01%, 0.02%, 0.05%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, or 1%, etc.), more preferably ≤0.5%, and even more preferably ≤0.05%.

[0040] In this invention, the mass percentage of solid components in the chemically amplified positive photosensitive resin composition refers to the sum of the mass percentages of all components except solvent E.

[0041] In a second aspect, the present invention provides a method for preparing a chemically amplified positive photosensitive resin composition as described in the first aspect, the method comprising the following steps: mixing each component in the chemically amplified positive photosensitive resin composition evenly to obtain the chemically amplified positive photosensitive resin composition.

[0042] Thirdly, the present invention provides a microlens, the raw materials for which the microlens is prepared include the chemically amplified positive photosensitive resin composition as described in the first aspect.

[0043] Fourthly, the present invention provides a method for preparing a microlens as described in the third aspect, the method comprising method A and method B; Method A includes the following steps: (1) A resin layer is obtained by coating a chemically amplified positive photosensitive resin composition as described in the first aspect onto a substrate; (2) The resin layer is selectively exposed; (3) Develop the exposed resin layer; (4) The resin layer after development is subjected to heat reflow treatment to obtain microlenses; Method B includes the following steps: (S1) A photoresist layer is formed by coating a chemically amplified positive photosensitive resin composition as described in the first aspect onto a lens material substrate. (S2) Selectively expose the photoresist layer; (S3) The exposed photoresist layer is developed to form a patterned structure; (S4) The developed photoresist layer is heat-treated to form a mask layer with a microlens morphology; (S5) Using the mask layer as an etching barrier layer, the microlens pattern is transferred to the lens material substrate by dry etching to obtain the microlens.

[0044] Preferably, the thickness of the resin layer obtained in step (1) and the photoresist layer obtained in step (S1) are each independently 1 μm - 3 μm, for example, 1 μm, 1.2 μm, 1.4 μm, 1.6 μm, 1.8 μm, 2 μm, 2.2 μm, 2.4 μm, 2.6 μm, 2.8 μm or 3 μm, etc.

[0045] Preferably, the temperature of the heat reflux treatment in step (4) is 90℃-100℃ (e.g., 90℃, 92℃, 94℃, 96℃, 98℃ or 100℃, etc.), and the time is 3 min-8 min (e.g., 3 min, 4 min, 5 min, 6 min, 7 min or 8 min, etc.).

[0046] Preferably, the substrate in step (1) comprises a silicon wafer.

[0047] It should be noted that the present invention does not impose any special restrictions on the specific methods and process parameters of exposure, development in steps (2), (3), (S2), and (S3), and heat treatment in step (S4). Commonly used methods in the field are applicable.

[0048] Compared with the prior art, the present invention has the following beneficial effects: (1) By designing the specific composition of the chemically amplified positive photosensitive resin composition, the present invention effectively reduces the Tg and reflux temperature of the first resin A and the second resin B through the synergistic effect of the first resin A and the second resin B containing acetal-type acid unstable group structural units (structural unit a1 in the first resin A and structural unit b1 in the second resin A), thereby reducing the reflux temperature of preparing microlenses using the chemically amplified positive photosensitive resin composition, achieving the goal of preparing microlenses at low temperature reflux (≤100℃), and improving the specific gravity, resolution and etching resistance of the microlenses.

[0049] (2) By controlling the mass ratio of the first resin A and the second resin B in the chemically amplified positive photosensitive resin composition within a specific range, the present invention has prepared a chemically amplified positive photosensitive resin composition and a microlens with excellent performance. Attached Figure Description

[0050] Figure 1 It is the resin B1-1 provided by this invention. 1 H-NMR spectrum; Figure 2 It is the resin B1-2 provided by this invention. 1 H-NMR spectrum; Figure 3 This is an SEM image of the microlens provided in Application Example 1 of the present invention. Detailed Implementation

[0051] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be considered as specific limitations thereof.

[0052] The sources of some components in the following examples and comparative examples are described in Table 1 below: Table 1 The preparation method of resin B1-1 is as follows: A linear phenolic resin (purchased from Shengquan, PF8063-2) with Mw=5100 and PDI=4.2 was dissolved in PGMEA to prepare a polymer solution with a solid content of 30%. After cooling to room temperature, nitrogen was purged. 100 parts by mass of the polymer solution containing the linear phenolic resin were taken, and 26 parts by mass of ethyl vinyl ether were added, followed by 0.3 parts by mass of trifluoroacetic acid. After reacting for 12 hours, triethylamine, equivalent to twice the mass of trifluoroacetic acid, was added to terminate the reaction. Finally, the precipitate was repeatedly dissolved and precipitated three times with n-heptane and ethyl acetate, and dried in a vacuum oven at 60°C. The resulting resin was a resin in which some hydroxyl groups of the linear phenolic resin were 1-ethoxyethylated. This resin was named B1-1. Resin B1-1 was then subjected to… 1 H-NMR analysis, such as Figure 1 As shown, by Figure 1 It can be seen that 30% of the hydroxyl groups in the linear phenolic resin are replaced by 1-ethoxyethyl ether; and the Mw of resin B1-1 was tested by gel permeation chromatography (GPC) and found to be 6000, with a PDI of 4.2.

[0053] The preparation method of resin B1-2 is as follows: A linear phenolic resin (purchased from Shengquan, PF8063-2) with Mw=5100 and PDI=4.2 was dissolved in PGMEA to prepare a polymer solution with a solid content of 30%. After cooling to room temperature, nitrogen was purged. 100 parts by mass of the polymer solution containing the linear phenolic resin were taken, and 39 parts by mass of ethyl vinyl ether were added. The synthesis was carried out using the same steps as the preparation method of resin B1-1. The resulting resin is a resin in which some hydroxyl groups in the linear phenolic resin are 1-ethoxyethylated. This resin is named B1-2. Resin B1-2 was then subjected to… 1 H-NMR analysis, such as Figure 2 As shown, by Figure 2 It can be seen that 40% of the hydroxyl groups in the linear phenolic resin are replaced by 1-ethoxyethyl ether; and the Mw of resin B1-2 was tested by gel permeation chromatography (GPC) and found to be 6100, with a PDI of 4.2.

[0054] Examples 1-9, Comparative Examples 1-4 Examples 1 to 9 and Comparative Examples 1 to 4 respectively provide a chemically amplified positive photosensitive resin composition and its preparation method. The specific composition of the chemically amplified positive photosensitive resin composition is shown in Table 2 below. In Table 2, the amounts (parts) of the first resin A, the second resin B, the photoacid generator C, the quencher D, and the solvent E are all by mass. The amount (%) of the surfactant F is calculated based on the mass percentage of the solid component in the chemically amplified positive photosensitive resin composition being 100%.

[0055] The preparation method of the chemically amplified positive photosensitive resin composition is as follows: the components in the chemically amplified positive photosensitive resin composition are mixed evenly to obtain the chemically amplified positive photosensitive resin composition.

[0056] Table 2 Application Example 1 This application example provides a microlens and its fabrication method, the fabrication method of which is as follows: (1) Hexamethyldisilazane (HMDS) treatment was performed on a silicon wafer to obtain a coated substrate. The chemically amplified positive photosensitive resin composition provided in Example 1 was spin-coated onto the silicon wafer, and then heat treatment was performed to remove the solvent (pre-baking conditions: 90°C, 90 s) to obtain a resin layer with a thickness of 2 μm. (2) The photoresist is selectively exposed using an exposure machine through a mask, with an exposure energy of 100 mJ / cm². 2 ; (3) The exposed resin layer is developed. The developer is an aqueous solution of 2.38 wt% tetramethylammonium hydroxide (TMAH). The development time is 60s. The resin layer is rinsed with ultrapure water for 20 seconds and then dried. (4) The resin layer after development is subjected to heat reflow treatment at 95°C for 5 min to obtain microlenses.

[0057] The microstructure of the microlenses provided in Example 1 was characterized using a scanning electron microscope, and the results are as follows: Figure 3 As shown. By Figure 3 It can be seen that the microlens was successfully prepared by the chemically amplified positive photosensitive resin composition provided in Example 1 using a low-temperature process (heat reflow treatment temperature ≤100℃), indicating that the chemically amplified positive photosensitive resin composition provided in Example 1 has a low Tg.

[0058] Application Examples 2-9, Comparison with Application Examples 1-4 Application Examples 2 to 9 and Comparative Application Examples 1 to 4 each provide a microlens and its preparation method. The only difference from Application Example 1 is that the chemically amplified positive photosensitive resin composition provided in Example 1 is replaced with the chemically amplified positive photosensitive resin composition provided in Examples 2 to 9 and Comparative Examples 1 to 4, while other conditions are the same as in Application Example 1.

[0059] The performance of the microlenses provided in the above application examples and comparative application examples was tested using the following specific test methods: Contrast The resin layer patterns obtained in step (1) of the above application examples and comparative application examples are exposed at different exposure doses (step (2)). Then, step (3) is performed. Since the chemically amplified positive photosensitive resin composition of the present invention is a positive gel system, its film thickness will decrease until it is zero as the exposure energy increases. The slope obtained by plotting the normalized residual film thickness with the logarithm of its corresponding exposure energy is the contrast ratio γ. The higher the contrast ratio, the greater the difference in dissolution rate between the exposed area and the non-exposed area, and the better the photolithography performance. The case where the contrast ratio γ < 5 is set as "×", and the case where the contrast ratio γ ≥ 5 is set as "○".

[0060] <Pattern Reflow> The cross-sectional shapes of the microlens patterns provided in the above application examples and comparative application examples were observed using a scanning electron microscope. The pattern's reflowability was evaluated when the cross-sectional shape remained unchanged ("×") and when the cross-sectional shape changed to a semi-circle ("○").

[0061] <Etching resistance> The dry etching rate can be calculated from the Ohnish number (ON). Empirical findings from Ohnish indicate that the etching rate of a polymer is a linear function of ON, i.e., the number of atoms (N) in the repeating unit of the polymer divided by the number of carbon atoms (N0). C Subtract the number of oxygen atoms (N) O ), directional structures with higher carbon content tend to be more resistant to etching; ; The microlenses provided in the above application examples and comparative application examples were subjected to dry etching (CF4 plasma etching) in plasma obtained from CF4 gas: The CF4 plasma etching conditions are as follows: Apparatus: Reactive ion etching equipment; Gas: CF4; Gas flow rate: 30 mL / min; Pressure within the chamber: 4 Pa; Output power (RF) applied to generate plasma: 120 W; Processing time: 30 min; The etching rate (the thickness of the film etched per unit time) is determined by the difference in film thickness of the resin layer formed by the chemically amplified positive photosensitive resin composition before and after etching. This etching rate is used as an indicator and evaluated according to the following criteria: ○: etching rate ≤ 50 nm / min; ×: etching rate > 50 nm / min.

[0062] The performance test results are shown in Table 3 below: Table 3 As shown in Tables 2 and 3, this invention, through the design of the specific composition of the chemically amplified positive photosensitive resin composition, and by the synergistic effect of the first resin A and the second resin B containing acetal-type acid-instable structural units, and by controlling the mass ratio of the first resin A and the second resin B within a specific range, effectively reduces the Tg and reflow temperature of the first resin A and the second resin B. This, in turn, lowers the reflow temperature for fabricating microlenses using this chemically amplified positive photosensitive resin composition, achieving the goal of fabricating microlenses at low-temperature reflow (≤100℃), and improving the specific gravity, resolution, and etching resistance of the microlenses. Therefore, the chemically amplified positive photosensitive resin composition provided by this invention is suitable for forming microlens patterns on lens material layers as mask layers for dry etching.

[0063] The applicant declares that the detailed process flow of this invention is illustrated by the above embodiments, but this invention is not limited to the above detailed process flow, that is, it does not mean that this invention must rely on the above detailed process flow to be implemented. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of raw materials for the product of this invention, addition of auxiliary components, and selection of specific methods, etc., all fall within the protection scope and disclosure scope of this invention.

Claims

1. A chemically amplified positive photosensitive resin composition, characterized in that, The chemically amplified positive photosensitive resin composition includes the following components: first resin A, second resin B, photoacid generator C, quencher D, and solvent E; The first resin A includes structural units having the following structural units: a1 and a2. ； in, Indicates the connection site; , Each can independently represent any one of hydrogen atoms, C1-C6 straight-chain or branched alkyl groups, or C3-C6 cycloalkyl groups; , Each of the following can be independently represented: a straight-chain or branched alkyl group of C1-C6, a cycloalkyl group of C3-C6, or an alkoxy group of C1-C6. , , Each can independently represent any one of hydrogen atoms, C1-C12 straight-chain or branched alkyl groups, or C3-C12 cycloalkyl groups; m1 and m3 each independently represent integers from 0 to 4, and m2 represents integers from 1 to 5, and 1 ≤ m1 + m2 ≤ 5; The second resin B includes structural units having the following structural units: formula b1 and formula b2. ； in, Indicates the connection site; R b1 It represents any one of C1-C6 straight-chain or branched alkyl, C3-C6 cycloalkyl, and C1-C6 alkoxy; R b2 R b3 R b4 Each can independently represent any one of hydrogen atoms, C1-C12 straight-chain or branched alkyl groups, or C3-C12 cycloalkyl groups; n1 and n3 each independently represent integers from 0 to 4, and n2 represents integers from 1 to 4, and 1≤n1+n2≤4; The mass ratio of the first resin A to the second resin B is 60:40-80:

20.

2. The chemically amplified positive photosensitive resin composition according to claim 1, characterized in that, Each of m1 and m3 independently represents 0; Preferably, m2 represents 1; Preferably, the first resin A comprises resin A1 having the following structural units: ； In resin A1, the ratio of x to y is 55:45-80:

20. Preferably, the weight-average molecular weight of the first resin A is 5000-15000.

3. The chemically amplified positive photosensitive resin composition according to claim 1 or 2, characterized in that, n1 and n3 each independently represent 0; Preferably, n2 represents 1; Preferably, the second resin B comprises resin B1 having the following structural unit: ； In resin B1, the ratio of p to q is 55:45-80:

20. Preferably, the weight-average molecular weight of the second resin B is 2000-7000; Preferably, the PDI of the second resin B is 2.5-5.

0.

4. The chemically amplified positive photosensitive resin composition according to any one of claims 1-3, characterized in that, With the sum of the mass parts of the first resin A and the second resin B being 100 parts, the mass part of the photoacid generator C is 0.5 parts to 30 parts, preferably 1 part to 20 parts, and more preferably 1 part to 5 parts.

5. The chemically amplified positive photosensitive resin composition according to any one of claims 1-4, characterized in that, With the sum of the mass parts of the first resin A and the second resin B being 100 parts, the mass part of the quenching agent D is 0.0001-5 parts, more preferably 0.0001-4 parts, and even more preferably 0.001-3 parts.

6. The chemically amplified positive photosensitive resin composition according to any one of claims 1-5, characterized in that, With the sum of the mass parts of the first resin A and the second resin B being 100 parts, the mass part of the solvent E is 200-400 parts, preferably 300-400 parts. Preferably, the chemically amplified positive photosensitive resin composition further includes surfactant F.

7. A method for preparing a chemically amplified positive photosensitive resin composition as described in any one of claims 1-5, characterized in that, The preparation method includes the following steps: The components in the chemically amplified positive photosensitive resin composition are mixed evenly to obtain the chemically amplified positive photosensitive resin composition.

8. A microlens, characterized in that, The raw materials for preparing the microlens include the chemically amplified positive photosensitive resin composition as described in any one of claims 1-6.

9. A method for preparing a microlens as described in claim 8, characterized in that, The preparation method includes method A and method B; Method A includes the following steps: (1) A chemically amplified positive photosensitive resin composition as described in any one of claims 1-6 is coated on a substrate to obtain a resin layer; (2) The resin layer is selectively exposed; (3) Develop the exposed resin layer; (4) The resin layer after development is subjected to heat reflow treatment to obtain microlenses; Method B includes the following steps: (S1) A photoresist layer is formed by coating a chemically amplified positive photosensitive resin composition as described in any one of claims 1-6 onto a lens material substrate. (S2) Selectively expose the photoresist layer; (S3) The exposed photoresist layer is developed to form a patterned structure; (S4) The developed photoresist layer is heat-treated to form a mask layer with a microlens morphology; (S5) Using the mask layer as an etching barrier layer, the microlens pattern is transferred to the lens material substrate by dry etching to obtain the microlens.

10. The preparation method according to claim 9, characterized in that, The thicknesses of the resin layer obtained in step (1) and the photoresist layer obtained in step (S1) are each 1 μm - 3 μm independently; Preferably, the temperature of the heat reflux treatment in step (4) is 90℃ - 100℃ and the time is 3 min - 8 min.

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