Photoresist stripping compositions for electronic applications

Abstract

This disclosure provides a photoresist stripping composition and a method for stripping photoresist using the photoresist stripping composition, wherein the photoresist stripping composition comprises an organic amine of formula (I): wherein R1 is hydrogen or an alkyl group having 1 to 12 carbon atoms; R2 is an alkylene group having 1 to 12 carbon atoms; R3 is hydrogen, a methyl group, or an ethyl group; R4 is an alkyl group having 1 to 12 carbon atoms, and n is an integer from 1 to 4. The photoresist stripping composition may also contain diethylene glycol monoethyl ether and other compounds.

Description

Technical Field

[0001] This disclosure generally relates to photoresist stripping compositions for electronic manufacturing applications. Background Technology

[0002] Generally, photoresist stripper compositions used in electronics manufacturing applications typically contain polar solvents, organic amines, and additives such as surfactants and / or inhibitors. The presence of organic amines in photoresist stripper compositions is well-known in the electronics processing industry, particularly in photoresist stripping or cleaning processes. Organic amines are used in these processes to dissolve polar polymers, monomers, and compounds.

[0003] A conventional process for stripping or cleaning photoresist in electronic applications involves immersing a substrate with photoresist in a photoresist stripper composition. In recent years, spray stripping processes have also been used to enhance production efficiency and reduce the amount of photoresist stripper composition used in stripping or cleaning processes. Spray stripping also allows for the processing of large semiconductor wafers and large-screen displays. During a spray stripping process, a photoresist stripper composition is sprayed onto the substrate. However, this spray stripping process cannot be used to apply conventional photoresist stripper compositions because it cannot completely remove the photoresist. Furthermore, it is known that organic amines in conventional photoresist stripper compositions can corrode metals associated with electronic devices (e.g., Cu and / or Al), potentially leading to unacceptable defects in the electronic devices. Another problem with many organic amines used in electronic processing is their less-than-ideal flash points. Therefore, there is a need in the art for an organic amine that has an acceptable flash point while maintaining photoresist stripping performance. Summary of the Invention

[0004] This disclosure provides a photoresist stripping composition for electronic manufacturing applications that addresses the problems noted above. Specifically, as discussed herein, the photoresist stripping composition of this disclosure provides a more desirable flash point while still maintaining the photoresist stripping properties required for electronic manufacturing applications (e.g., weaker metal corrosion, but good solubility for electronic materials such as photoresists).

[0005] This disclosure provides a photoresist stripping composition comprising an organic amine of formula (I):

[0006]

[0007] Wherein R1 is hydrogen or an alkyl group having 1 to 12 carbon atoms; R2 is an alkylene group having 1 to 12 carbon atoms; R3 is hydrogen, a methyl group, or an ethyl group; R4 is an alkyl group having 1 to 12 carbon atoms, and n is an integer from 1 to 4. For embodiments, R1 to R4 may have preferred embodiments. For example, for formula (I), R1 is a methyl group; R2 is a methylene group and / or R3 is a methyl group. For embodiments herein, R4 may be an alkyl group having 1 to 4 carbon atoms. For embodiments herein, n may be 1. For embodiments, the organic amine of formula (I) may be selected from the group consisting of: 1-((1-propoxypropyl-2-yl)oxy)-prop-2-amine, 1-((1-butoxypropyl-2-yl)oxy)-prop-2-amine, 1-((1-methoxypropyl-2-yl)oxy)prop-2-amine, and combinations thereof. For embodiments, the photoresist stripping composition provided herein may also contain diethylene glycol monoethyl ether. For example, a photoresist stripping composition may contain 10 wt.% to 99.99 wt.% of an organic amine of formula (I) and 90 wt.% to 0.01 wt.% of diethylene glycol monoethyl ether.

[0008] Embodiments of this disclosure may further include a method for stripping photoresist using the photoresist stripping composition of this disclosure. For each embodiment, the method of stripping photoresist may include providing a surface having a photoresist layer and applying the photoresist stripping composition of this disclosure to a substrate having photoresist. Embodiments of this disclosure may further include a method of stripping photoresist, the method comprising providing a surface having a photoresist layer and stripping at least a portion of the photoresist layer from the surface using the photoresist stripping composition of this disclosure. For each embodiment, the substrate may be selected from the group consisting of semiconductor wafers, printed circuit boards, OLED displays, and liquid crystal displays. For each embodiment, the photoresist layer may be selected from photoresist layers formed of photosensitive polyimide layers, phenolic resin layers, acrylic layers, or combinations thereof. For each embodiment, the surface as provided herein may include an interconnect metal layer, wherein the photoresist stripping composition inhibits corrosion of the interconnect metal layer. Detailed Implementation

[0009] This disclosure provides a photoresist stripping composition for electronic manufacturing applications that addresses the problems noted above. Specifically, as discussed herein, the photoresist stripping composition of this disclosure provides a more desirable flash point while still maintaining the photoresist stripping properties required for electronic manufacturing applications (e.g., weaker metal corrosion, but good solubility for electronic materials such as photoresists).

[0010] As disclosed herein, the terms “composition,” “formulation,” or “mixture” refer to a physical blend of different components that is obtained by simply mixing the different components in a physical manner.

[0011] As disclosed herein, the terms “stripping” or “cleaning” or “removal” have the same meaning, such as removing photoresist from a substrate.

[0012] As disclosed herein, all percentages and parts of all components in the composition refer to weight. All percentages of all components in the composition are calculated based on the total weight of the composition. The sum of the percentages of all components is 100%.

[0013] As disclosed herein, the term "alkyl" refers to a straight-chain or branched alkyl group having 1 to 12 carbon atoms, typically 1 to 10 carbon atoms, more typically 1 to 6 carbon atoms, and most typically 1 to 4 carbon atoms.

[0014] As disclosed herein, the term "alkylene" refers to a straight-chain or branched alkylene group having 1 to 12 carbon atoms, typically 1 to 10 carbon atoms, more typically 1 to 6 carbon atoms, and most typically 1 to 4 carbon atoms.

[0015] This disclosure provides a photoresist stripping composition comprising an organic amine of formula (I):

[0016]

[0017] Wherein R1 is hydrogen or an alkyl group having 1 to 12 carbon atoms; R2 is an alkylene group having 1 to 12 carbon atoms; R3 is hydrogen, a methyl group, or an ethyl group; R4 is an alkyl group having 1 to 12 carbon atoms, and n is an integer from 1 to 4. For various embodiments, R1 is an alkyl group having 1 to 10 carbon atoms, typically R1 is an alkyl group having 1 to 8 carbon atoms, more typically R1 is an alkyl group having 1 to 6 carbon atoms, and most typically R1 is an alkyl group having 1 to 4 carbon atoms. Exemplary R1 groups include straight-chain, branched, and cycloalkyl groups, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, hexyl, 1-methylbutyl, 2-methylbutyl, and 3-methylbutyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, or 2,2-dimethylpropyl, 1-ethyl-propyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, or 4-methylpentyl, 1,1-di... Methylbutyl, 1,2-dimethylbutyl, 1,3-dimethylbutyl, 2,2-dimethylbutyl, 2,3-dimethylbutyl or 3,3-dimethylbutyl, 1-ethylbutyl or 2-ethylbutyl, 1-ethyl-1-methylpropyl and 1,1,2-trimethylpropyl or 1,2,2-trimethylpropyl, heptyl, octyl, nonyl, decyl, cyclopentyl, methylcyclopentyl, cyclohexyl, methylcyclohexyl, ethylcyclohexyl and propylcyclohexyl. Preferably, R1 is hydrogen or an alkyl group having 1 to 4 carbon atoms, wherein examples of alkyl groups include methyl, ethyl, propyl, isopropyl, butyl or isobutyl. For various embodiments, R2 is an alkylene group having 1 to 10 carbon atoms, typically R2 is an alkylene group having 1 to 8 carbon atoms, more typically R2 is an alkylene group having 1 to 6 carbon atoms, and most typically R2 is an alkylene group having 1 to 4 carbon atoms. Exemplary R2 groups include straight-chain and branched alkylene groups, such as methylene, ethylene, propylene, isopropylene, butylene, isobutylene, sec-butylene, tert-butylene, pentylene, hexylene, 1-methylbutylene, 2-methylbutylene and 3-methylbutylene, 1,1-dimethylpropylene, 1,2-dimethylpropylene or 2,2-dimethylpropylene, 1-ethylpropylene, 1-methylpentylene, 2-methylpentylene, 3-methyl... The alkylene group may contain 4-methylpentanediol, 1,1-dimethylbutylene, 1,2-dimethylbutylene, 1,3-dimethylbutylene, 2,2-dimethylbutylene, 2,3-dimethylbutylene or 3,3-dimethylbutylene, 1-ethylbutylene or 2-ethylbutylene, 1-ethyl-1-methylpropylene, and 1,1,2-trimethylpropylene or 1,2,2-trimethylpropylene, heptamethine, octylene, nonylene, and decylene. Preferably, R2 is an alkylene group having 1 to 4 carbon atoms, wherein examples of alkylene groups include methylene, ethylene, propylene, or butylene.For various embodiments, R4 is an alkyl group having 1 to 10 carbon atoms, typically R4 is an alkyl group having 1 to 8 carbon atoms, more typically R4 is an alkyl group having 1 to 6 carbon atoms, and most typically R4 is an alkyl group having 1 to 4 carbon atoms. Exemplary R4 groups include straight-chain, branched, and cycloalkyl groups, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, hexyl, 1-methylbutyl, 2-methylbutyl, and 3-methylbutyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, or 2,2-dimethylpropyl, 1-ethyl-propyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, or 4-methylpentyl, 1,1-dimethylpropyl ... Methylbutyl, 1,2-dimethylbutyl, 1,3-dimethylbutyl, 2,2-dimethylbutyl, 2,3-dimethylbutyl or 3,3-dimethylbutyl, 1-ethylbutyl or 2-ethylbutyl, 1-ethyl-1-methylpropyl and 1,1,2-trimethylpropyl or 1,2,2-trimethylpropyl, heptyl, octyl, nonyl, decyl, cyclopentyl, methylcyclopentyl, cyclohexyl, methylcyclohexyl, ethylcyclohexyl and propylcyclohexyl. Preferably, R4 is an alkyl group having 1 to 4 carbon atoms, wherein examples of alkyl groups include methyl, ethyl, propyl, isopropyl, butyl or isobutyl. For various embodiments, specific examples of organic amines of formula (I) include organic amines wherein R1 is a methyl group; R2 is a methylene group and / or R3 is a methyl group; and wherein R4 can be an alkyl group having 1 to 4 carbon atoms as described herein. For embodiments herein, n is an integer from 1 to 4. For the embodiments, when n is 2 to 4, R3 can be the same or different (i.e., the compound may include a combination of two or more of hydrogen, methyl, and / or ethyl). Typically, n is an integer from 1 to 3 or an integer from 1 to 2. Preferably, for the various embodiments provided herein, n is 1.

[0018] For implementation schemes, specific examples of organic amines of formula (I) may be selected from the group consisting of: 1-((1-propoxypropyl-2-yl)oxy)-prop-2-amine, 1-((1-butoxypropyl-2-yl)oxy)-prop-2-amine, 1-((1-methoxypropyl-2-yl)oxy)prop-2-amine and combinations thereof.

[0019] For the implementation, the flash point of the organic amine of formula (I) can be in the range of 75°C to 150°C, wherein the flash point is determined according to ASTM D56. Another example of the flash point value of the organic amine of formula (I) can include 77°C to 95°C (determined according to ASTM D56). For the organic amine of formula (I) and / or the photoresist stripping composition of this disclosure, a flash point value higher than 60°C to 70°C is advantageous because photoresist stripping procedures during electronics manufacturing are typically performed at temperatures around 60°C to 70°C to obtain better stripping performance.

[0020] The preparation of organic amines of formula (I), i.e., alkyl ether amines, is known in the art, and various alkyl ether amines are commercially available. One synthetic modality involves the reductive amination of ethylene glycol ethers with ammonia using a NiCoCuReB catalyst as described in U.S. Patent No. 9,574,126. Ethylene glycol ether starting materials are available from Dow Chemical Company, such as those produced by DOWANOL. ™ CELLOSOLVE ™ and CARBITOL ™ Trademark names were obtained, such as propylene glycol n-butyl ether (DOWANOL). ™ PnB ethylene glycol ether), dipropylene glycol methyl ether (DOWANOL) ™ DPM ethylene glycol ether, dipropylene glycol n-propyl ether (DOWANOL) ™ DPnP ethylene glycol ether), propylene glycol n-propyl ether (DOWANOL) ™ PnP ethylene glycol ether), dipropylene glycol n-butyl ether (DOWANOL) ™ DPnB ethylene glycol ether), ethylene glycol monohexyl ether (hexyl cellosolve) ™ Solvent), ethylene glycol mono-n-propyl ether (propyl cellosol ether) ™ Solvents), diethylene glycol monohexyl ether, ethylene glycol mono-n-propyl ether (propyl cellosol ether) ™ Solvent), diethylene glycol monohexyl ether (hexylCARBITOL) ™ Solvent, diethylene glycol monobutyl ether (butylCARBITOL) ™ Solvent) and triethylene glycol monobutyl ether.

[0021] Typically, the photoresist stripping compositions of this disclosure comprise 100 wt.% of an organic amine of formula (I) (e.g., the organic amine of formula (I) is used in pure form without any additional compounds and / or additives). For example, in one embodiment, the photoresist stripping composition consists solely of an organic amine of formula (I) (100 wt.% of the organic amine of formula (I)), wherein no additional compounds are added to the photoresist stripping composition (0 wt.% of additional compounds). In other embodiments, the photoresist stripping compositions of this disclosure may contain additional compounds as discussed herein.

[0022] For various embodiments, the photoresist stripping composition of this disclosure may further comprise an organic amine of formula (I) and other compounds. For example, the photoresist stripping composition of this disclosure may comprise 10 wt.% to 99.99 wt.% of an organic amine of formula (I) and 90 wt.% to 0.01 wt.% of other compounds, wherein wt.% is based on the total weight of the photoresist stripping composition. Other examples include: 20 wt.% to 99.99 wt.% of an organic amine of formula (I) and 80 wt.% to 0.01 wt.% of another compound; 30 wt.% to 99.99 wt.% of an organic amine of formula (I) and 70 wt.% to 0.01 wt.% of another compound; 40 wt.% to 99.99 wt.% of an organic amine of formula (I) and 60 wt.% to 0.01 wt.% of another compound; and 50 wt.% to 99.99 wt.% of an organic amine of formula (I) and 50 wt.% to 0.01 wt.% of another compound comprising the photoresist stripping composition of this disclosure, wherein wt.% is based on the total weight of the photoresist stripping composition.

[0023] Other compounds used with the organic amine of formula (I) may include, but are not limited to, ethylene glycol solvents such as ethylene glycol and propylene glycol, ethylene glycol ethers, alcohols, amides, carbonates, and combinations of solvents comprising at least one of the aforementioned solvents. Examples of ethylene glycol ethers for various embodiments may include ethylene glycol diethyl ether, diethylene glycol dimethyl ether, ethylene glycol monobutyl ether, triethylene glycol dimethyl ether, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol propyl ether, ethylene glycol butyl ether, diethylene glycol methyl ether, diethylene glycol ethyl ether, diethylene glycol butyl ether, diethylene glycol propyl ether, triethylene glycol methyl ether, triethylene glycol ethyl ether, triethylene glycol butyl ether, triethylene glycol propyl ether, propylene glycol methyl ether, propylene glycol ethyl ether, propylene glycol propyl ether, propylene glycol butyl ether, dipropylene glycol methyl ether, dipropylene glycol ethyl ether, dipropylene glycol propyl ether, dipropylene glycol butyl ether, tripropylene glycol methyl ether, tripropylene glycol ethyl ether, tripropylene glycol propyl ether, tripropylene glycol butyl ether, etc.

[0024] In one exemplary embodiment, the photoresist stripping composition disclosed herein comprises 10 wt.% to 99.99 wt.% of an organic amine of formula (I) and 90 wt.% to 0.01 wt.% of diethylene glycol monoethyl ether. In another embodiment, the photoresist stripping composition of this disclosure may comprise 20 wt.% to 99.99 wt.% of an organic amine of formula (I) and 80 wt.% to 0.01 wt.% of diethylene glycol monoethyl ether; 30 wt.% to 99.99 wt.% of an organic amine of formula (I) and 70 wt.% to 0.01 wt.% of diethylene glycol monoethyl ether; 40 wt.% to 99.99 wt.% of an organic amine of formula (I) and 60 wt.% to 0.01 wt.% of diethylene glycol monoethyl ether; and 50 wt.% to 99.99 wt.% of an organic amine of formula (I) and 50 wt.% to 0.01 wt.% of diethylene glycol monoethyl ether, wherein wt.% is based on the total weight of the photoresist stripping composition.

[0025] Other compounds may also be included in the photoresist stripping compositions disclosed herein. The selection of other compounds to be used with the photoresist stripping compositions disclosed herein may be based on the type of photoresist involved in the electronic manufacturing application. Examples of such compounds include, but are not limited to, n-methyl-2-pyrrolidone and dimethyl sulfoxide.

[0026] The photoresist stripping composition disclosed herein may further comprise an etching inhibitor. The etching inhibitor may comprise a compound containing nitrogen, sulfur, oxygen, etc., having unshared electron pairs. Specifically, the etching inhibitor may contain hydroxyl groups, hydrogen sulfide groups, etc. The reactive groups of the etching inhibitor can physically and chemically adhere to the metal to prevent corrosion of the metal-containing thin layer. Examples of etching inhibitors include, but are not limited to, triazole compounds such as benzotriazole, toluenetriazole, etc. The photoresist stripping composition disclosed herein may comprise 0 wt.% to 10 wt.%, typically 0.1 wt.% to 8 wt.%, more typically 0.5 wt.% to 5 wt.%, and most typically 1 wt.% to 3 wt.% of etching inhibitor, wherein wt.% is based on the total weight of the photoresist composition.

[0027] The photoresist stripping composition disclosed herein may also contain a surfactant. For various embodiments, the photoresist stripping composition disclosed herein may contain 20 wt.% or less of a surfactant, typically 15 wt.% or less, more typically 10 wt.% or less, and most typically 10 wt.% or less, where wt.% is based on the total weight of the photoresist composition. Surfactants may be added to help remove insoluble photoresist residues and reduce silicon etching that may occur when exposed to the photoresist stripping composition. Examples of suitable surfactants include, but are not limited to, anionic, cationic, and / or nonionic surfactants such as fluoroalkyl surfactants, polyethylene glycol, polypropylene glycol, polyethylene glycol ethers or polypropylene glycol ethers, carboxylates, dodecylbenzenesulfonic acid or salts thereof, polyacrylate polymers, silicone or modified silicone polymers, alkynyl glycols or modified alkynyl glycols, alkylammonium or modified alkylammonium salts, and combinations of surfactants comprising at least one of the aforementioned surfactants.

[0028] For various embodiments, the photoresist stripping composition of this disclosure may further comprise an alkanolamine compound. The alkanolamine compound suitable for use in this disclosure may be represented by chemical formula (II):

[0029]

[0030] R5 and R6 can be hydrogen, alkyl, aryl, alkylaryl, aralkyl, alkyl alcohol, aryl alcohol, alkylaryl alcohol or aralkyl alcohol, and R7 can be alkyl alcohol, aryl alcohol, alkylaryl alcohol or aralkyl alcohol, etc.

[0031] Examples of suitable alkanolamines include diethylene glycolamine (DGA), monoethanolamine, 2-(N-methylamino)ethanol, diethanolamine, triethanolamine, tert-butyldiethanolamine, isopropanolamine, diisopropanolamine, 2-amino-1-propanol, 3-amino-1-propanol, isobutanolamine, 2-amino-2-ethoxyethanol and 2-amino-2-methoxy-propanol, 2-(2-hydroxyethylamino)ethanol, 2-(N-hydroxyethylamino)-ethanol, 1-hydroxy-2-aminobenzene, 2-[(2-aminoethyl)-(2-hydroxyethyl)-amino]-ethanol, 2-(2-aminoethoxy)ethanol, and 2-(2-aminoethoxy)-ethanol. -Propanol, N,N,N-tris(2-hydroxyethyl)-amino, N-aminoethyl-N'-hydroxyethyl-ethylenediamine, N,N'-dihydroxyethyl-ethylenediamine, 2-[2-(2-aminoethoxy)-ethylamino]-ethanol, 2-[2-(2-aminoethylamino)-ethoxy]-ethanol, 2-[2-(2-aminoethoxy)-ethoxy]-ethanol, isopropanolamine, 3-amino-1-propanol, 2-amino-1-propanol, 2-(N-methylamino)ethanol, 2-(2-aminoethylamino)ethanol, tris(hydroxymethyl)aminoethane, triethanolamine, trimethanolamine, triisopropanolamine, or mixtures thereof.

[0032] For each embodiment, the photoresist stripping composition may contain 0.1 wt.% to 100 wt.% of an organic amine of formula (I) and one or more alkanolamine compounds, typically 1 wt.% to 70 wt.% of an organic amine of formula (I), more typically 5 wt.% to 60 wt.% of an organic amine of formula (I), and most typically 10 wt.% to 50 wt.% of an organic amine of formula (I), based on the total weight of the photoresist stripping composition.

[0033] Embodiments of this disclosure may further include a method for stripping photoresist using the photoresist stripping composition of this disclosure. For embodiments, the method of stripping photoresist may include providing a surface having a photoresist layer and applying the photoresist stripping composition of this disclosure to a substrate having photoresist. Embodiments of this disclosure may further include a method of stripping photoresist, the method comprising providing a surface having a photoresist layer and stripping at least a portion of the photoresist layer from the surface using the photoresist stripping composition of this disclosure. Applying the photoresist stripping composition of this disclosure to a substrate having photoresist, or stripping at least a portion of the photoresist layer from a surface using the photoresist stripping composition of this disclosure, may include spraying the photoresist stripping composition of this disclosure onto the substrate having photoresist. Applying the photoresist stripping composition of this disclosure to a substrate having photoresist, or stripping at least a portion of the photoresist layer from a surface using the photoresist stripping composition of this disclosure, may include immersing the substrate having photoresist in the photoresist stripping composition of this disclosure. Photoresist, as used herein, is generally suitable for any layer containing photoresist. Therefore, for example, based on the teachings of this disclosure, the photoresist stripping compositions and methods described herein can be used to remove photoresist and photoresist residues. In one embodiment, the above methods may further include a step of rinsing the substrate with water after the stripping or application steps provided above.

[0034] For various implementations, the substrate used herein can be selected from the group consisting of semiconductor wafers, printed circuit boards, OLED displays, and liquid crystal displays. Typically, the substrate may also include metal interconnects, such as copper interconnects, molybdenum interconnects, and aluminum interconnects.

[0035] For each embodiment, the photoresist layer can be selected from photoresist layers formed of: a photosensitive polyimide layer, a phenolic resin layer, an acrylic layer, or a combination thereof. For each embodiment, the surface provided herein may include an interconnect metal layer, wherein the photoresist release composition inhibits corrosion of the interconnect metal layer. The organic amine according to this disclosure can inhibit corrosion of interconnect metals such as copper, molybdenum, and aluminum.

[0036] Some embodiments of this disclosure will now be described in detail in the following examples.

[0037] Example

[0038] In the embodiments, various terms and names for materials are used, including, for example, the following:

[0039] Material

[0040] The materials used in the embodiments (IE) and comparative embodiments (CE) of the present invention include the following materials:

[0041] Table 1. Materials and Composition

[0042]

[0043] Table 2 summarizes the formulations for IE and CE:

[0044] Table 2

[0045]

[0046] CE A - CE C and IE 1 - IE 3

[0047] CE A - CE C and IE 1 - IE 3 are to be used in their pure form as provided by the manufacturer.

[0048] Preparation of IE 4-IE 6 photoresist stripping composition

[0049] For IE 4 to IE 6, Table 2 provides the designed amounts of glycol ether solvent mixed with the corresponding amounts of glycol ether amine, where these amounts are given as wt.% based on the total weight of the photoresist stripping composition. A 1.5 ml sample of each of IE 4 to IE 6 was prepared by adding the glycol ether solvent and glycol ether amine to a vial and then hand-shaking the vial at 22°C.

[0050] Evaluation of the performance of photoresist stripping compositions

[0051] 3 mL of AZ SFP-1400 photoresist solution was dropped onto the surface of an indium tin oxide (ITO) coated glass substrate (substrate size 100 mm × 100 mm × 1 mm). The substrate was spin-coated at 500 rpm for 10 seconds to spin-coat the photoresist solution onto the substrate. The spin speed was then increased to 1000 rpm and maintained for 30 seconds to achieve a 1 μm thick photoresist film. The spin-coated photoresist was heated at 130 °C for 10 minutes under a nitrogen atmosphere to completely evaporate the solvent and cure the photoresist film on the glass substrate.

[0052] For each of CEA-CEC and IE1-IE6, 30 μL of the photoresist stripping composition was dispensed onto the photoresist film prepared as described above at room temperature (22°C). The glass substrate was gently shaken by hand, and the time for complete removal of the photoresist film was recorded.

[0053] The photoresist stripping performance of CE A-CE C and IE 1-IE 6 can be found in Table 3, where shorter stripping times indicate better stripping performance. The photoresist stripping compositions for CE A to CE C are found in WO 2021 / 035673A1. As seen in Table 3, the photoresist stripping performance of each of CE A-CE C and IE 1-IE 6 is comparable. The stripping time for IE 2 is longer compared to other examples, which is attributed to the larger molecular size of dipropylene glycol n-butyl ether-amine. However, during manufacturing, the photoresist-coated substrate is immersed in the photoresist stripping composition and stripped for more than 40 seconds. Therefore, as long as the stripping time is less than 40 seconds, the performance of the photoresist stripping composition will be considered commercially acceptable. Thus, all evaluated CE and IE compositions show acceptable performance.

[0054] Table 3. Performance of the photoresist stripping composition

[0055]

[0056] Flash point analysis

[0057] The flash point of each glycol ether amine as shown in Table 1 (samples) was tested on a Seta Closed Cup according to ASTM D56. Measurements were performed using 50 mL samples loaded into a sample cup. The expected flash point was set at 20 °C. The sample was held at a temperature 15 °C below the expected flash point for 30 minutes. The sample temperature was then increased at a rate of 1 °C / min, and a test flame was applied when the sample temperature was approximately 5 °C below its expected flash point, with temperature readings then taken in increments of 0.5 °C each time. The results of the flash point analysis are shown in Table 4.

[0058] During industrial manufacturing, photoresist stripping processes are typically performed at temperatures around 60°C to 70°C to achieve better stripping performance. Therefore, throughout the process (especially when organic amines are used alone), photoresist stripping compositions with flash points below this temperature range need to be considered. As shown in Table 4, the ethylene glycol ether amines CEA to CEC have flash points below the aforementioned temperatures, which is less desirable than flash points above these temperatures. Also as shown in Table 4, the flash points of IE1 to IE3 are higher than the aforementioned temperatures, which is a significant advantage of the photoresist stripping compositions disclosed herein.

[0059] Table 4. Flash points of CEA-CEC and IE1-IE3

[0060]

Claims

1. A photoresist stripping composition, the photoresist stripping composition comprising: Organic amines of formula (I): Wherein R1 is hydrogen or an alkyl group having 1 to 12 carbon atoms; R2 is an alkylene group having 1 to 12 carbon atoms; R3 is hydrogen, a methyl group or an ethyl group; R4 is an alkyl group having 1 to 12 carbon atoms, and n is an integer from 1 to 4.

2. The photoresist stripping composition according to claim 1, wherein R1 is a methyl group.

3. The photoresist stripping composition according to any one of claims 1 and 2, wherein R2 is a methylene group.

4. The photoresist stripping composition according to any one of claims 1 to 3, wherein R3 is a methyl group.

5. The photoresist stripping composition according to any one of claims 1 to 4, wherein R4 is an alkyl group having 1 to 4 carbon atoms.

6. The photoresist stripping composition according to any one of claims 1 to 5, wherein n is 1.

7. The photoresist stripping composition according to any one of claims 1 to 6, wherein the organic amine of formula (I) is selected from the group consisting of: 1-((1-propoxypropyl-2-yl)oxy)-prop-2-amine, 1-((1-butoxypropyl-2-yl)oxy)-prop-2-amine, 1-((1-methoxypropyl-2-yl)oxy)-prop-2-amine and combinations thereof.

8. The photoresist stripping composition according to any one of claims 1 to 7, wherein the photoresist stripping composition further comprises diethylene glycol monoethyl ether.

9. The photoresist stripping composition according to claim 8, wherein the photoresist stripping composition comprises 10 wt.% to 99.99 wt.% of the organic amine of formula (I) and 90 wt.% to 0.01 wt.% of the diethylene glycol monoethyl ether.

10. A method for stripping photoresist, the method comprising: Provide a surface with a photoresist layer; as well as The photoresist stripping composition according to any one of claims 1 to 9 is applied to a substrate having the photoresist.

11. A method for stripping photoresist, the method comprising: Provide a surface with a photoresist layer; as well as At least a portion of the photoresist layer is peeled off from the surface using the photoresist stripping composition according to any one of claims 1 to 9.

12. The method according to any one of claims 10 or 11, wherein the substrate is selected from the group consisting of: semiconductor wafers, printed circuit boards, OLED displays, and liquid crystal displays.

13. The method according to any one of claims 10 to 12, wherein the photoresist layer is selected from photoresist layers formed from: a photosensitive polyimide layer, a phenolic resin layer, an acrylic layer, or a combination thereof.

14. The method according to any one of claims 10 to 13, wherein the surface comprises an interconnect metal layer, and the photoresist stripping composition inhibits corrosion of the interconnect metal layer.

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