Photoresist cleaning agent for III-V semiconductor compounds as well as preparation method and application of photoresist cleaning agent

Abstract

The invention relates to a photoresist cleaning agent for a III-V semiconductor compound and a preparation method and application of the photoresist cleaning agent, and the photoresist cleaning agent for the III-V semiconductor compound comprises the following components in parts by weight: 0.5-2 parts of a corrosion inhibitor; 1-20 parts of an organic base; 10 to 20 parts of a wetting agent; 70-90 parts of an organic solvent; and 1-5 parts of ultrapure water. The corrosion inhibitor adopted by the invention provides active chemical protection for gallium arsenide; a proper amount of moisture ensures effective formation of the protective film; the whole system acts together to inhibit the corrosion tendency of alkylol amine to various metals, so that effective protection can be provided for gallium arsenide.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor manufacturing processes, and particularly relates to photoresist cleaning agents for III-V semiconductor compounds, their preparation methods, and applications. Background Technology

[0002] The development of photoresist cleaning agent technology for LED red and yellow LED processes (gallium arsenide) is primarily driven by the industry's technological upgrades and the resulting demands for innovative material performance. As the penetration rate of red and yellow LEDs in the display and lighting fields continues to increase, traditional wet cleaning agents (such as alkaline TMAH) exhibit corrosion rates of 0.5-1 nm / min on GaAs materials, easily leading to lattice defects and failing to meet the requirements of high-precision processes. Hydroxylamine-based semi-aqueous cleaning agents, by adding corrosion inhibitors (BTA), reduce the corrosion rate to 0.05 nm / min while achieving a crosslinked photoresist removal rate of over 200 nm / min, becoming the current mainstream solution. Especially with the accelerated commercialization of Mini / MicroLEDs, the high aspect ratio (>5:1) structure poses even greater challenges to the penetration ability of cleaning agents. The synergistic application of dry cleaning agents (low-temperature plasma-assisted) and wet processes has become a key direction for overcoming technological bottlenecks.

[0003] The growth in market demand further drives technological transformation and the process of domestic substitution. The LED industry is experiencing significant structural growth; for example, the penetration rate of MiniLED TVs is projected to reach 25% by 2025, directly boosting demand for high-end cleaning agents—in 2024, the proportion of high-end cleaning agents adapted to Mini / Micro processes in China reached 37.2%, and the market share of dry cleaning agents is expected to increase to 35% by 2025. Under this trend, domestic companies are collaborating with wafer foundries to develop cleaning agent products adapted to advanced processes, gradually replacing international manufacturers (whose market share was approximately 18% in 2024). Simultaneously, support from national special funds and production line verification platforms has further accelerated the industrialization process of domestically produced high-end products.

[0004] Technically, the technology has undergone multiple iterations and has developed into a mature system: early solvent-based cleaning agents have been gradually replaced by water-based systems containing hydrogen peroxide. In gallium arsenide (GaAs) processes, hydroxylamine-based solutions have become mainstream due to their high removal efficiency. When combined with phenolic corrosion inhibitors, the corrosion rate of GaAs can be precisely controlled, remaining stable below 0.1 nm / min, effectively avoiding lattice defects. Meanwhile, the proportion of semi-aqueous fluorinated systems adapted to single-wafer cleaning equipment continues to increase. This system performs exceptionally well in the stripping of high aspect ratio (>5:1) structures, achieving a metal electrode to dielectric material selection ratio >10:1, meeting the fine process requirements of high-density LED displays. Leveraging the deep integration of semiconductor and LED processes, international technologies have accounted for over 60% of the application in high-end Mini / MicroLED processes, demonstrating significant advantages in process stability and batch consistency.

[0005] Domestic development focuses on composite corrosion inhibitor technology as a core breakthrough. Through independent research and development of mercapto-nitrogenazole composite formulations, functional groups chelate arsenic and gallium ions to form a dual surface protective layer, further reducing the GaAs corrosion rate to the 0.05nm / min level. In low-to-mid-end GaAs LED processes, the localization rate even exceeds 80%. However, it should be noted that domestic products still lag behind in core indicators: insufficient compatibility with advanced processes such as Mini / MicroLEDs results in international manufacturers still occupying about 18% of the high-end market share. Domestic substitution still needs continuous breakthroughs in the high-end field.

[0006] In the gallium arsenide (GaAs) manufacturing process for red and yellow LED chips, the core technology of photoresist cleaning agents lies in solving a fundamental microscopic challenge: how to completely remove the photoresist while perfectly protecting the chemically reactive and easily corroded GaAs substrate and its intricate patterns. This is fundamentally different from the process of fabricating blue LEDs on sapphire substrates. GaAs is extremely sensitive to alkaline conditions, and traditional cleaning agents can cause severe damage, leading to surface roughness and deterioration of electrical performance.

[0007] Modern cleaning agents typically employ alkaline composite systems based on organic amines. Their action occurs in two steps: first, solvent molecules penetrate the photoresist polymer network, causing it to swell and weakening its structure and adhesion; then, the alkaline component breaks down the photoresist molecular chains, degrading it into easily soluble small molecular fragments. To ensure GaAs safety, corrosion inhibitors such as phenols or azoles must be added to the formulation. These inhibitor molecules preferentially adsorb onto the GaAs surface, forming a dense monomolecular protective film that effectively blocks OH... - It attacks ions and stabilizes potentially dissolved metal ions through complexation, thereby providing critical protection for sensitive substrates in chemically reactive environments.

[0008] Currently, existing technologies in this field are mainly based on purely organic systems. These systems rely on organic solvents such as N-methylpyrrolidone (NMP) and dimethyl sulfoxide (DMSO) as the main components, combined with organic bases and highly efficient inhibitors. Their core advantage lies in fundamentally eliminating the problem of GaAs alkaline corrosion exacerbated by water molecules as the reaction medium.

[0009] In the field of photoresist stripping in LED red and yellow process (gallium arsenide), organic amine compounding technology achieves efficient photoresist stripping and GaAs protection through component optimization, and related patented technologies have been implemented and adapted to LED processes.

[0010] Mianyang Aisas Electronics' pending patent CN117908340A focuses on a synergistic system of organic amines and composite additives. The organic amine component comprises 10-30 parts, combined with ether / alcohol organic solvents, and crucially introduces 1-(2-hydroxyethyl)piperazine and methylbenzyltriazole. The amines are responsible for breaking the crosslinking bonds of the photoresist, while the additives simultaneously inhibit GaAs corrosion and metal electrode damage. When treating residual Au / Ti mask layers in GaAs-based LEDs, the photoresist removal rate reaches 180 nm / min, and the Au electrode corrosion rate is <0.02 nm / min. This system is suitable for medium-power red and yellow LED chip manufacturing processes, balancing stripping efficiency and electrode protection.

[0011] Hangzhou Greenda's published patent CN119781262A focuses on multi-process compatibility: an organic amine system is compounded with protic / aprotic solvents, and Al corrosion inhibitors and metal potential regulators are added. By controlling the proportion of alicyclic amines (60%-80%), corrosion-free stripping of various LED electrodes such as Cu, Al, and ITO is achieved. In the multi-metal wiring process for red and yellow LEDs, the residual adhesive removal rate exceeds 99%, the GaAs surface roughness RMS is <1.5nm, and the bath life is extended to 150 hours. This can reduce the mass production cost of Mini red and yellow LEDs by approximately 20%, meeting the requirements for fine patterning.

[0012] Organic amine-based photoresist cleaners have significant limitations in performance adaptability. On one hand, they lack compatibility with extreme processes. When faced with the high aspect ratio intricate trenches of Mini / MicroLED chips, the penetration ability of organic amines and solvents decreases, easily leaving photoresist residue at the bottom of the trenches, leading to short-circuit risks in subsequent electrode fabrication. Furthermore, at high temperatures (>80℃), they may accelerate the complexation reaction between the GaAs substrate and amines, damaging the chip's PN junction. On the other hand, the selectivity of the etching inhibitors is limited; while they can protect GaAs substrates, their protective effect on novel LED electrodes such as Cu and Al is poor.

[0013] This technology faces dual bottlenecks in industrial application: cost and process coordination. The organic amine compound system relies on high-purity alicyclic amines and special corrosion inhibitors as raw materials, resulting in higher procurement costs than ordinary alkanolamine materials, which contradicts the LED industry's need for cost reduction and efficiency improvement.

[0014] Therefore, to address the shortcomings of existing photoresist cleaning agents, such as high corrosion risk to gallium arsenide substrates and insufficient photoresist stripping efficiency, this invention constructs a water-based organic composite system. This technology achieves efficient and safe cleaning of gallium arsenide chips while providing good protection for the GaAs metal through the synergistic effect of a highly efficient saponification reaction activated by trace amounts of water and the penetration and swelling of the organic solvent. Summary of the Invention

[0015] The technical problem solved by this invention is that the cleaning agents used for III-V semiconductor compound photoresists in the prior art cannot form protection for gallium arsenide and often have poor photoresist removal ability.

[0016] In view of the technical problems existing in the prior art, the present invention designs a cleaning agent for III-V semiconductor compound photoresist, its preparation method and application, which has the effect of protecting gallium arsenide and has a better cleaning effect on photoresist.

[0017] It should be noted that, in this invention, unless otherwise specified, the specific meaning of "comprising" in relation to composition definition and description includes both open-ended meanings such as "comprising," "including," etc., and closed-ended meanings such as "composed of," etc., and similar meanings.

[0018] To solve the aforementioned technical problems, the present invention adopts the following solution:

[0019] [The first technical solution]

[0020] A cleaning agent for III-V semiconductor compound photoresists, characterized in that, by weight, it comprises the following components:

[0021] Corrosion inhibitor 0.5-2 parts;

[0022] 1-20 parts of organic base;

[0023] 10-20 parts wetting agent;

[0024] 70-90 parts organic solvent;

[0025] 1-5 parts ultrapure water;

[0026] The corrosion inhibitor is a mixture of polythiol ester compounds and sugars.

[0027] Further, the polythiol ester compound is one or more of pentaerythritol tetra(3-mercaptopropionic acid) ester, trimethylolpropane tri(3-mercaptopropionic acid) ester, pentaerythritol tetramercaptoacetate, pentaerythritol tetra(mercaptobutyrate) ester, and hexa(3-mercaptopropionic acid) dipentaerythritol ester.

[0028] Furthermore, the sugar substance is one or more of glucose, glyceraldehyde, pentose, arabinose, mannose, fructose, galactose, heptose, 4-aminophenyl β-D-galactopyranoside, 6-O-galloylglucose, and α-glucose-α-glucoside.

[0029] Furthermore, the mass ratio of the polythiol ester compound to the sugar is (1-15):1.

[0030] Furthermore, the organic base is an alcoholamine.

[0031] Furthermore, the organic base is one or more of monoethanolamine, diethanolamine, triethanolamine, n-propanolamine, isopropanolamine, 2-(diethylamino)ethanol, ethyldiethanolamine, and diethylene glycolamine.

[0032] Further, the organic base is any two of monoethanolamine, diethanolamine, triethanolamine, n-propanolamine, isopropanolamine, 2-(diethylamino)ethanol, ethyl diethanolamine, and diethylene glycolamine, and the mass ratio of the two alcoholamines is (0.5-10):(0.5-12).

[0033] Furthermore, the wetting agent is one or more of diethylene glycol, glycerin, 1,2-propanediol, and 1,3-propanediol.

[0034] Furthermore, the organic solvent is one or more of sulfoxide, sulfone, imidazolidinone, pyrrolidone, imidazolinone, amide, and alcohol ether.

[0035] Furthermore, the sulfoxide is dimethyl sulfoxide, etc.

[0036] Furthermore, the sulfone is sulfolane, etc.

[0037] Furthermore, the imidazolidinone is one or both of 2-imidazolidinone and 1,3-dimethyl-2-imidazolidinone.

[0038] Furthermore, the pyrrolidone is one or both of N-methylpyrrolidone and N-cyclohexylpyrrolidone.

[0039] Furthermore, the imidazolinone is 1,3-dimethyl-2-imidazolinone.

[0040] Furthermore, the amide is one or both of dimethylformamide and dimethylacetamide.

[0041] Furthermore, the alcohol ether is one or both of diethylene glycol monobutyl ether and dipropylene glycol monomethyl ether.

[0042] In this invention, in order to further optimize the performance of the photoresist cleaning agent for III-V semiconductor compounds, the components can be optimized as follows: 0.5-1 parts of corrosion inhibitor; 10-20 parts of organic base; 15-20 parts of wetting agent; 75-85 parts of organic solvent; and 3-5 parts of ultrapure water.

[0043] In this invention, the polythiol ester compound is preferably trimethylolpropane tris(3-mercaptopropionic acid) ester.

[0044] In this invention, the carbohydrate is preferably 6-O-galloyl glucose.

[0045] In this invention, the preferred mass ratio of the polythiol ester compound to the sugar is (5-12):1.

[0046] In this invention, the organic base is preferably monoethanolamine or diethanolamine.

[0047] In this invention, the mass ratio of monoethanolamine to diethanolamine is (0.5-10):(0.5-12).

[0048] In this invention, the mass ratio of monoethanolamine to diethanolamine is preferably 3:10.

[0049] In this invention, the wetting agent is preferably diethylene glycol.

[0050] [Second Technical Solution]

[0051] A method for preparing a photoresist cleaning agent for III-V semiconductor compounds, comprising the following steps:

[0052] Step 1: Weigh out the respective amounts of each component;

[0053] Step 2: At 80℃-90℃, the corrosion inhibitor is added to ultrapure water and stirred for a certain period of time. After cooling to room temperature, the wetting agent, organic solvent and organic base are added. After stirring for a certain period of time, the photoresist cleaning agent for the III-V semiconductor compound is obtained.

[0054] Further, in step 2, the corrosion inhibitor is added to ultrapure water and stirred for 2.3-3.5 hours.

[0055] Furthermore, in step 2, the wetting agent and organic solvent are first added and mixed and stirred for 20-40 minutes, and then the organic base is added and stirred for another 20-40 minutes.

[0056] [The third technical solution]

[0057] A method of using the above-mentioned photoresist cleaning agent for III-V semiconductor compounds includes the following steps:

[0058] Step 1: Immerse the LED chip in the LED chip cleaning agent at 80-95℃ for 10-40 minutes to obtain the immersed LED chip;

[0059] Step 2: Rinse the soaked LED chip in ultrapure water at least twice to complete the LED chip cleaning process.

[0060] [Fourth technical solution]

[0061] The use of the aforementioned III-V semiconductor compound photoresist cleaner in cleaning photoresist on LED chips.

[0062] This invention provides a photoresist cleaning agent for III-V semiconductor compounds, its preparation method, and its uses, which have the following beneficial effects:

[0063] 1. In this invention, polythiol ester compounds serve as a key additive in the organic alcohol amine system. The multiple thiol groups (-SH) in their molecules are central to their protective function. These thiol groups exhibit a strong chemical affinity for metal surfaces, forming a dense protective film to block corrosive media. A small amount of ultrapure water in the system is a necessary reaction medium, promoting the adsorption and film formation of the thiol compounds on the metal surface, thus working synergistically with the organic solvent. For gallium arsenide, the thiol groups bond with the gallium atoms on its surface, forming a stable passivation layer that replaces the unstable natural oxide layer under alkaline conditions, thereby resisting the corrosion of alcohol amines.

[0064] In summary, this formulation achieves multi-metal protection through the synergistic effect of its components. The polythiol ester compounds are the core corrosion inhibitors, primarily providing active chemical protection for gallium arsenide; an appropriate amount of moisture ensures the effective formation of the protective film; the entire system works together to inhibit the corrosive tendency of alkanolamines to various metals, thus providing effective protection for gallium arsenide. This technology achieves this through the synergistic effect of a highly efficient saponification reaction activated by trace amounts of moisture and the permeation and swelling of the organic solvent. Attached Figure Description

[0065] Figure 1 : OM image of a chip with photoresist before cleaning, magnified 500 times;

[0066] Figure 2 : OM image of the chip magnified 500 times after cleaning with the cleaning agent of Example 1. Detailed Implementation

[0067] The present invention will be further described below with reference to specific embodiments and accompanying drawings:

[0068] In this invention, Examples 1-10 and Comparative Examples 1-4 disclose a variety of cleaning agents, the components and their mass ratios of which are shown in Tables 1 and 2.

[0069] Table 1. Components and proportions of photoresist cleaning agents for III-V semiconductor compounds in Examples 1-10

[0070]

[0071] Table 2. Components and proportions of cleaning agents in Comparative Examples 1-4

[0072]

[0073] The preparation method of the photoresist cleaning agent for III-V semiconductor compounds of the present invention is as follows:

[0074] Step 1: Weigh out the respective amounts of each component;

[0075] Step 2: At 80℃-90℃, first add the corrosion inhibitor to ultrapure water and stir for 2.5-3.5 hours. Then cool to room temperature, add the wetting agent, stir evenly, add the organic solvent, stir for 20-40 minutes, add the organic base and continue stirring for 20-40 minutes to obtain the photoresist cleaning agent for III-V semiconductor compounds.

[0076] Method of using the photoresist cleaning agent for III-V semiconductor compounds according to the present invention:

[0077] Step 1: Immerse the LED chip in the LED chip cleaning agent at 80-95℃ for 10-40 minutes to obtain the immersed LED chip;

[0078] Step 2: Rinse the soaked LED chip in ultrapure water at least twice to complete the LED chip cleaning process.

[0079] Regarding performance testing and explanation:

[0080] The test method for performance 1 metal corrosion is as follows:

[0081] ICP-MS (Inductively Coupled Plasma Mass Spectrometry) was used to test the corrosion performance of different cleaning agents on metals. The specific test method was as follows: A 4×4 cm⁻¹ plate was prepared... 2 Gallium arsenide epitaxial wafers were immersed in a cleaning agent at 80°C for 6 hours, and then the concentration of metal ions in the cleaning agent was measured by ICP-MS to investigate the corrosion rate of metals by different cleaning agents.

[0082] The test method for performance 2 cleaning effect is as follows:

[0083] After LED chips with sapphire as the substrate undergo photoresist masking, exposure, and pattern transfer to obtain the desired pattern, the residual photoresist cleaning process includes the following steps:

[0084] Step 1: Immerse the LED chip in the photoresist cleaning agent of Example 1 at 80°C for 10 minutes to obtain the immersed LED chip;

[0085] Step 2: Rinse the soaked LED chip in ultrapure water at least twice to complete the LED chip cleaning process.

[0086] The ultrapure water used in step 2 is deionized water with a resistance of at least 18 MΩ.

[0087] The performance test results of the cleaning agents obtained in Examples 1-10 and Comparative Examples 1-4 are shown in Table 3.

[0088] Table 3 Test Data

[0089]

[0090] Analysis and explanation of the test results:

[0091] As can be seen from the test data in Table 3, compared with the comparative example, the photoresist cleaning agent of the present invention has a corrosion rate of less than 3 Å / min on GaAs and has a good protective effect on GaAs metal.

[0092] Comparative Example 1 showed an increased corrosion rate due to the lack of trimethylolpropane tris(3-mercaptopropionic acid) ester.

[0093] Comparative Example 2 showed an increased corrosion rate due to the lack of 6-O-galloglucoside.

[0094] Comparative Example 3 used methyl 3-mercaptopropionate instead of trimethylolpropane tris(3-mercaptopropionate), which led to an increase in the corrosion rate.

[0095] Comparative Example 4 showed that replacing trimethylolpropane tris(3-mercaptopropionic acid) ester with 3-amino-5-mercapto-1,2,4-triazole resulted in an increased corrosion rate.

[0096] Comparative Example 5 used chitosan instead of 6-O-galloglucoside, which led to an increase in the corrosion rate.

[0097] Further comparison can be made using the accompanying diagrams in the instruction manual:

[0098] Figure 1 OM image of a chip with photoresist before cleaning, magnified 500 times; Figure 2 The image shows an OM (Optical Model) image of the chip after cleaning with the cleaning agent of Example 1, magnified 500 times.

[0099] from Figure 1 and Figure 2 It can be seen that the cleaning agent in Example 1 has a good adhesive removal effect, and there is no obvious adhesive residue around the electrode.

[0100] The present invention has been described above by way of example with reference to the embodiments and accompanying drawings. Obviously, the implementation of the present invention is not limited to the above-described manner. Any improvements made by adopting the inventive concept and technical solution of the present invention, or the direct application of the inventive concept and technical solution of the present invention to other occasions without modification, are all within the protection scope of the present invention.

Claims

1. A photoresist cleaning agent for III-V semiconductor compounds, characterized in that, Based on parts by weight, it includes the following components: Corrosion inhibitor 0.5-2 parts; 1-20 parts of organic base; 10-20 parts wetting agent; 70-90 parts organic solvent; 1-5 parts ultrapure water; The corrosion inhibitor is a mixture of polythiol ester compounds and sugars.

2. The photoresist cleaning agent for III-V semiconductor compounds according to claim 1, characterized in that: The polythiol ester compounds are one or more of pentaerythritol tetra(3-mercaptopropionic acid) ester, trimethylolpropane tri(3-mercaptopropionic acid) ester, pentaerythritol tetramercaptoacetate, pentaerythritol tetra(mercaptobutyrate) ester, and hexa(3-mercaptopropionic acid) dipentaerythritol ester.

3. The photoresist cleaning agent for III-V semiconductor compounds according to claim 1, characterized in that: The sugars are one or more of the following: glucose, glyceraldehyde, pentose, arabinose, glucose, mannose, fructose, galactose, heptose, 4-aminophenyl β-D-galactopyranoside, 6-O-galloylglucose, and α-glucose-α-glucoside.

4. The photoresist cleaning agent for III-V semiconductor compounds according to claim 1, characterized in that: The mass ratio of the polythiol ester compound to the sugar is (1-15):

1.

5. The photoresist cleaning agent for III-V semiconductor compounds according to claim 1, characterized in that: The organic base is an alcohol amine.

6. The photoresist cleaning agent for III-V semiconductor compounds according to claim 1, characterized in that: The wetting agent is one or more of diethylene glycol, glycerin, 1,2-propanediol, and 1,3-propanediol.

7. The photoresist cleaning agent for III-V semiconductor compounds according to claim 1, characterized in that: The organic solvent is one or more of sulfoxide, sulfone, imidazolidinone, pyrrolidone, imidazolinone, amide, and alcohol ether.

8. A method for preparing a photoresist cleaning agent for III-V semiconductor compounds according to any one of claims 1-7, characterized in that, Includes the following steps: Step 1: Weigh out the respective amounts of each component; Step 2: At 80℃-90℃, add the corrosion inhibitor to ultrapure water, stir for a certain time, cool to room temperature, then add the wetting agent, organic solvent, and organic base, and continue stirring for a certain time to obtain the photoresist cleaning agent for III-V semiconductor compounds.

9. A method of using the photoresist cleaning agent for III-V semiconductor compounds according to any one of claims 1-7, characterized in that, Includes the following steps: Step 1: Immerse the LED chip in the photoresist cleaning agent at 80-95℃ to obtain the immersed LED chip; Step 2: Rinse the soaked LED chip in ultrapure water at least twice to complete the LED chip cleaning process.

10. The use of the photoresist cleaner for III-V semiconductor compounds according to any one of claims 1-7 for cleaning photoresist on LED chips.

Images