TWI824513B - Decomposition and cleaning composition and its manufacturing method, and cleaning method of adhesive polymer - Google Patents

Abstract

Provided is a decomposition cleaning composition exhibiting high etching speed. A decomposition and cleaning composition containing (A) an N-substituted amide compound in which two alkyl groups are bonded to a amide nitrogen atom as an aprotic solvent, and (B) quaternary alkylammonium fluoride Or the hydrate, wherein the N-substituted amide is a compound in which two hydrogen atoms on the carbon atom at the alpha position of the amide nitrogen atom of the N-substituted amide compound are substituted with pendant oxygen groups. The content of oxidized derivatives is 550 ppm by mass or less.

Description

Decomposition and cleaning composition and its manufacturing method, and cleaning method of adhesive polymer

The present disclosure relates to a decomposition cleaning composition and its manufacturing method, as well as a cleaning method for adhesive polymers. The present disclosure particularly relates to a composition that can be used for decomposing and cleaning an adhesive containing an adhesive polymer, a manufacturing method thereof, and a cleaning method for an adhesive polymer formed using the composition, wherein the Adhesives are residues on the device wafer during the thinning process of semiconductor wafers and are used to temporarily bond the device wafer and the support wafer (carrier wafer).

In the three-dimensional packaging technology used to increase the density of semiconductors, the thickness of each semiconductor wafer becomes thinner, and a plurality of semiconductor wafers connected through silicon through-silicon electrodes (TSV) are stacked. Specifically, after the surface (rear surface) of the device wafer on which the semiconductor device is formed on which the device is not formed is reduced in thickness by polishing, electrodes including TSVs are formed on the back surface.

In the polishing step of the backside of the device wafer, in order to provide mechanical strength to the device wafer, a support wafer (also called a carrier wafer) is temporarily adhered to the semiconductor device formation surface of the device wafer by using an adhesive. . As the supporting wafer, for example, a glass wafer or a silicon wafer can be used. After the polishing step, an inorganic film containing metal wiring or electrode pads, an oxide film, a nitride film, etc., or an inorganic film containing Al, Cu, Ni, Au, etc., is formed on the polished surface (back surface) of the device wafer as required. Resin layer such as polyimide. After that, the back side of the device wafer is bonded to the tape with an acrylic adhesive layer fixed by a ring frame, thereby fixing the device wafer on the tape. Thereafter, the device wafer is separated from the support wafer (debonding), the adhesive on the device wafer is peeled off, and a cleaning agent is used to clean and remove residues of the adhesive on the device wafer.

For temporary bonding of device wafers, the adhesive used contains a polyorganosiloxane compound with good heat resistance as an adhesive polymer. In particular, if the adhesive is a cross-linked polyorganosiloxane compound, the cleaning agent is required to have two functions: cutting Si-O bonds and dissolving decomposition products with a solvent. Examples of such a cleaning agent include a cleaning agent in which a fluorine compound such as tetrabutylammonium fluoride (TBAF) is dissolved in a polar aprotic solvent. The fluoride ions of TBAF participate in the cleavage of Si-O bonds by forming Si-F bonds, thus imparting etching properties to the detergent. Polar aprotic solvents can dissolve TBAF and will not form solvation effects on fluoride ions through hydrogen bonding, thus improving the reactivity of fluoride ions.

Non-patent Document 1 (Advanced Materials, 11, 6, 492 (1999)) describes a 1.0 M TBAF solution using aprotic THF as a solvent, which can be used to decompose polydimethylsiloxane (PDMS) and Dissolve and remove.

Non-patent Document 2 (Advanced Materials, 13, 8, 570 (2001)) describes a solvent called TBAF. NMP, DMF and DMSO, which are the same aprotic solvents as THF, can be used.

Non-patent document 3 (Macromolecular Chemistry and Physics, 217, 284-291 (2016)) describes the results of the investigation of the etching rate of PDMS using each solvent of TBAF/organic solvent, and also describes the results of the etching rate with a higher etching rate. Comparison of the etching speeds of THF and DMF, and TBAF solutions using mixed solvents that changed the ratio of THF/DMF. [Prior technical literature] [Patent Document]

[Non-patent document 1] Advanced Materials, 11, 6, 492 (1999) [Non-patent document 2] Advanced Materials, 13, 8, 570 (2001) [Non-patent document 3] Macromolecular Chemistry and Physics, 217, 284-291 (2016)

[Problem to be solved by the invention]

In a decomposition and cleaning composition containing a fluorine compound such as TBAF and a solvent, it is considered that the function of the solvent is to fully dissolve the highly polar fluorine compound that is a reactive substance and to ensure the reaction of the fluoride ions contained in the fluorine compound. properties and dissolve the decomposition products of the adhesive. Aprotic N-substituted amide compounds, such as N-methylpyrrolidone (NMP), are known not to adversely affect the reactivity of fluoride ions and can dissolve the decomposition products of adhesives, so they can be beneficial. Used as a solvent that decomposes the cleaning composition.

However, the present inventors discovered that when an aprotic N-substituted amide compound is used as a solvent for decomposing the cleaning composition, a sufficient etching rate (ER) may not be obtained.

The present disclosure aims to provide a decomposition cleaning composition exhibiting high etching speed. [Means to solve the problem]

The present inventors found that in a decomposition and cleaning composition containing a quaternary alkylammonium fluoride or its hydrate and an N-substituted amide compound in which two alkyl groups are bonded to a amide nitrogen atom, Inevitably contains oxidized derivatives (peroxides, hydroxides, or imine compounds) produced by the oxidation of N-substituted amide compounds, and by setting the content of the above oxidized derivatives to a specified value Below, a high etching speed can be obtained.

That is, the present invention includes the following [1] to [16]. [1] A decomposition and cleaning composition containing (A) an N-substituted amide compound in which two alkyl groups are bonded to a amide nitrogen atom as an aprotic solvent, and (B) quaternary fluorination Alkylammonium or the hydrate, wherein N is a compound in which two hydrogen atoms located at the α-position of the carbon atom of the amide nitrogen atom of the N-substituted amide compound (A) are substituted with pendant oxy groups. -The content of substituted amide oxidation derivatives is 550 ppm by mass or less. [2] The decomposition and cleaning composition of [1], wherein the bromide ion concentration is 100 ppm by mass or less. [3] The decomposition and cleaning composition according to [1] or [2], further containing (C) an ether compound as an aprotic solvent. [4] The decomposition and cleaning composition of [3], wherein the total content of the (A) N-substituted amide compound and the (C) ether compound is 70 to 99.99% by mass. [5] The decomposition and cleaning composition according to any one of [1] to [4], wherein the aforementioned (A) N-substituted amide compound is a 2-pyrrolidone derivative compound represented by formula (1), (In the formula (1), R ¹ represents an alkyl group having 1 to 4 carbon atoms), the aforementioned N-substituted amide oxidation derivative is an N-substituted succinimide compound represented by the formula (4), (In formula (4), R ¹ represents an alkyl group having 1 to 4 carbon atoms). [6] The decomposition and cleaning composition according to [5], wherein the N-substituted amide compound (A) is a 2-pyrrolidone derivative compound in which R ¹ in the formula (1) is a methyl group or an ethyl group. [7] The decomposition and cleaning composition according to [3] or [4], wherein the ether compound (C) contains a dialkyl ether of a glycol represented by formula (2), R ² O(C _n H _2n O ₎ ^{_ _ _} , and an alkyl group of the group consisting of t-butyl, n is 2 or 3, x is an integer from 1 to 4). [8] The decomposition and cleaning composition according to [7], wherein the dialkyl ether of the aforementioned glycol is dipropylene glycol dimethyl ether. [9] The decomposition and cleaning composition according to any one of [3], [4], [7], and [8], wherein the ether compound (C) contains a dialkyl ether represented by formula (3) , R ⁴ OR ⁵ (3) (in the formula, R ⁴ and R ⁵ each independently represent an alkyl group having 4 to 8 carbon atoms). [10] The decomposition and cleaning composition according to [9], wherein the dialkyl ether is dibutyl ether. [11] The decomposition and cleaning composition according to any one of [1] to [10], wherein the aforementioned (B) quaternary alkylammonium fluoride is represented by R ⁶ R ⁷ R ⁸ R ⁹ N ⁺ F ^- For tetraalkylammonium fluoride, R ⁶ to R ⁹ are each independently an alkyl group selected from the group consisting of methyl, ethyl, n-propyl, isopropyl, and n-butyl. [12] The decomposition and cleaning composition according to any one of [1] to [11], wherein the content of the aforementioned (B) quaternary alkylammonium fluoride is 0.01 to 10% by mass. [13] The decomposition and cleaning composition according to any one of [1] to [12], which is a decomposition and cleaning composition of an adhesive polymer. [14] The decomposition and cleaning composition according to [13], wherein the adhesive polymer is a polyorganosiloxane compound. [15] A method of cleaning the adhesive polymer on the substrate using the decomposition and cleaning composition according to any one of [1] to [14]. [16] A method for producing a decomposition cleaning composition containing (A) an N-substituted amide compound in which two alkyl groups are bonded to a amide nitrogen atom as an aprotic solvent, and (B) A method for producing a decomposition and cleaning composition for quaternary alkylammonium fluoride or its hydrate, which includes placing a carbon atom at the alpha position of the amide nitrogen atom of the N-substituted amide compound (A) The above-mentioned (A)N- A substituted amide compound, and the aforementioned (B) quaternary alkylammonium fluoride or the hydrate. [Effects of the invention]

The disclosed decomposition cleaning composition system exhibits high etch rates.

The above description should not be regarded as revealing all embodiments of the present invention and all advantages of the present invention.

[The best way to implement the invention]

Hereinafter, the present invention will be described in further detail. However, the present invention is not limited only to the embodiments shown below.

[Decompose cleaning composition] A decomposition and cleaning composition according to an embodiment, which contains (A) an N-substituted amide compound in which two alkyl groups are bonded to a amide nitrogen atom as an aprotic solvent, and (B) quaternary fluorine alkylammonium or its hydrate. In the decomposition cleaning composition according to this embodiment, the compound is a compound in which two hydrogen atoms located at the α position of the carbon atom of the amide nitrogen atom of the (A) N-substituted amide compound are substituted with pendant oxygen groups. The content of the N-substituted amide oxidation derivative (also referred to as "N-substituted amide oxidation derivative" in this disclosure) is 550 ppm by mass or less.

The decomposition and cleaning composition of the present disclosure contains an N-substituted amide compound in which two alkyl groups as an aprotic solvent are bonded to the amide nitrogen atom (also referred to as "N-substituted amide compound in this disclosure"). ”). It is known that N-substituted amide compounds are gradually oxidized upon contact with oxygen to generate oxidized derivatives.

For example, if N-methylpyrrolidone (NMP) is oxidized by oxygen in the air, or dissolved oxygen in a solvent or a decomposition cleaning composition, the following mechanism will produce 5-containing peroxides: Hydroperoxy-1-methyl-2-pyrrolidone (NMP-5-OOH), 5-hydroxy-1-methyl-2-pyrrolidone (NMP-5-OH) as hydroxide, and the NMP oxidized derivative of N-methylsuccinimide (NMS) as an imine compound. NMP-5-OOH and NMP-5-OH will eventually be converted into NMS with a chemically stable structure.

Therefore, a decomposition cleaning composition containing an N-substituted amide compound as an aprotic solvent will inevitably contain oxidized derivatives of the N-substituted amide compound located in the normal manufacturing conditions and storage environment. N-Substituted amide compounds are compounds in which two hydrogen atoms on the carbon atom at the α position of the amide nitrogen atom are substituted with pendant oxygen groups (=O). Without wishing to be bound by any theory, peroxides and hydroxides, which are intermediate products of the oxidation reaction of N-substituted amide compounds, have an effect on the fluoride ions (F ^- ) supplied by the quaternary alkylammonium fluoride. Active and converts fluoride ions into difluoride ions (HF ₂ ^- ). For example, difluoride ions are less reactive than fluoride ions in cutting Si-O bonds. Therefore, it is considered that even in a decomposition cleaning composition containing an N-substituted amide compound as an aprotic solvent, a large amount of the above-mentioned compound, which is the final oxidation product of the N-substituted amide compound, is included. The concentration of fluoride ions in the neat composition is reduced and therefore exhibits a lower etch rate.

In the decomposition cleaning composition according to this embodiment, the content of the compound in which two hydrogen atoms located at the α-position of the carbon atom of the amide nitrogen atom of the N-substituted amide compound are substituted with pendant oxygen groups is below the specified value, so a high etching speed can be obtained.

<(A) N-substituted amide compound in which two alkyl groups are bonded to the amide nitrogen atom> N-substituted amide compounds with two alkyl groups bonded to the amide nitrogen atom are relatively highly polar aprotic solvents that can uniformly dissolve or disperse quaternary alkylammonium fluoride and its compounds in the composition. Hydrate. In the present disclosure, the two alkyl groups in the N-substituted amide compound may be the same or different. The number of carbon atoms of the alkyl group is preferably 1 to 10, and further preferably 1 to 5. An alkyl group can also participate in the formation of cyclic amide compounds. In this disclosure, "N-substituted amide compounds" also include urea compounds (carbamide compounds) in which two alkyl groups are bonded to the amide nitrogen atom. The N-substituted amide compound is not particularly limited, and various compounds can be used. Examples include N,N-dimethylformamide, N,N-diethylformamide, and N,N-dimethylformamide. Acyclic N-substituted amide such as acetamide, N,N-diethyl acetamide, N,N-dimethylpropionamide, N,N-diethylpropionamide, tetramethylurea, etc. Amine, 2-pyrrolidone derivatives, 2-piperidone derivatives, ε-caprolactam derivatives, 1,3-dimethyl-2-imidazolidinone, 1-methyl-3-ethyl-2 -Imidazolidinone, 1,3-diethyl-2-imidazolidinone, 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone (N,N' -Dimethylacrylamide) and other cyclic N-substituted amides. Among these, the use of cyclic N-substituted amide is preferred. The N-substituted amide compound system may be one type or a combination of two or more types.

In one embodiment, the N-substituted amide compound is a 2-pyrrolidone derivative compound represented by formula (1), (In formula (1), R ¹ represents an alkyl group having 1 to 4 carbon atoms). Examples of the alkyl group having 1 to 4 carbon atoms include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, and the like. Examples of the 2-pyrrolidone derivative compound represented by formula (1) include N-methylpyrrolidone (NMP), N-ethylpyrrolidone (NEP), N-propylpyrrolidone, N-butylpyrrolidone, and the like.

Due to its relatively high polarity, excellent solubility for quaternary alkylammonium fluoride, and easy availability, N-substituted amide compounds are derived from 2-pyrrolidone in formula (1) in which R ¹ is methyl or ethyl. The compound is preferably a compound, and the 2-pyrrolidone derivative compound (ie, N-methylpyrrolidone) in which R ¹ in the formula (1) is methyl is even more preferred.

In one embodiment, the content of the N-substituted amide compound in the decomposition and cleaning composition is 70 to 99.99 mass%, preferably 80 to 99.95 mass%, and more preferably 90 to 99.9 mass%. When the decomposition and cleaning composition contains an ether compound described below, the total content of the N-substituted amide compound and the ether compound in the decomposition and cleaning composition is preferably 70 to 99.99% by mass, and 80 to 99.95% by mass. is preferably 90 to 99.9% by mass.

＜N-Substituted amide oxidation derivatives＞ In the decomposition and cleaning composition according to one embodiment, the content of the N-substituted amide oxidation derivative is 550 ppm by mass or less. The content of the N-substituted amide oxidation derivative can be determined by gas chromatography using the conditions described in the Examples. The content of the N-substituted amide oxidation derivative in the decomposition and cleaning composition is preferably 500 ppm by mass or less, and still more preferably 450 ppm by mass or less.

For example, when the N-substituted amide compound is an embodiment of a 2-pyrrolidone derivative compound represented by formula (1), the N-substituted amide oxidized derivative is an N-substituted succinimide compound represented by formula (4), (In formula (4), R ¹ represents an alkyl group having 1 to 4 carbon atoms).

<(B) Quaternary alkylammonium fluoride or the hydrate> Quaternary alkylammonium fluoride or the hydrate system releases fluoride ions that participate in Si-O bond cleavage. Through the quaternary alkylammonium moiety, the quaternary alkylammonium fluoride as a salt can be dissolved in an aprotic solvent. As the quaternary alkylammonium fluoride, various compounds can be used without particular limitation. Examples of hydrates of quaternary alkylammonium fluoride include trihydrate, tetrahydrate, and pentahydrate. The quaternary fluorinated alkylammonium system may be one type or a combination of two or more types. The nonhydrate and hydrate systems of quaternary alkylammonium fluoride can be used in any ratio.

In one embodiment, the quaternary alkylammonium fluoride is a tetraalkylammonium fluoride represented by R ⁶ R ⁷ R ⁸ R ⁹ N ⁺ F ^- , and R ⁶ to R ⁹ are independently selected from methyl and ethyl groups. Alkyl group of the group consisting of , n-propyl, isopropyl, and n-butyl. From the viewpoint of ease of acquisition, it is preferred that R ⁶ to R ⁹ are all the same alkyl group. Examples of such quaternary alkylammonium fluoride include tetramethylammonium fluoride, tetraethylammonium fluoride, tetrapropylammonium fluoride, tetrabutylammonium fluoride, and the like. From the viewpoint of decomposition and cleaning performance, ease of acquisition, price, etc., tetrabutylammonium fluoride (TBAF) is the preferred quaternary alkylammonium fluoride.

In one embodiment, the content of the quaternary alkylammonium fluoride in the decomposition and cleaning composition is 0.01 to 10% by mass. Here, when the composition contains a hydrate of quaternary alkylammonium fluoride, the "content of quaternary alkylammonium fluoride" is a value converted only to the mass of quaternary alkylammonium fluoride. , does not include water and water quality. The content of the quaternary alkylammonium fluoride in the decomposition and cleaning composition is preferably 0.01 to 5 mass %, more preferably 0.05 to 2 mass %, and more preferably 0.1 to 1 mass %. In other embodiments, the content of the quaternary alkylammonium fluoride in the decomposition and cleaning composition is preferably 0.5 to 9 mass %, more preferably 1 to 8 mass %, and 2 to 5 mass %. Mass% or 4 to 8 mass% is more preferable. By setting the content of quaternary alkylammonium fluoride to 0.01% by mass or more, the adhesive polymer can be effectively decomposed and washed, and by setting it to 10% by mass or less, it is possible to prevent or inhibit device wafers. Corrosion of metal parts contained in the device forming surface.

If there is a special requirement to prevent or inhibit corrosion of metal parts, or to reduce the cost associated with the use of quaternary alkylammonium fluoride, the content of quaternary alkylammonium fluoride in the decomposition and cleaning composition can be set to 4 mass% or less, or can be set to 3 mass% or less. If a higher etching rate is required, the content of the quaternary alkylammonium fluoride in the decomposition cleaning composition can be set to 5 mass % or more, 6 mass % or more, or 7 mass % or more.

＜(C) Ether compound＞ The decomposition cleaning composition may further contain an ether compound as an aprotic solvent. By combining an ether compound and an N-substituted amide compound, a mixed solvent system showing high affinity for the adhesive surface can be formed. Using such a mixed solvent-based composition can achieve a high etching rate that effectively utilizes the reactivity of quaternary alkylammonium fluoride. Various compounds can be used without particular limitation as the ether compound. The ether compound may be one type or a combination of two or more types. It is preferable that the ether compound does not contain an ester structure or an amide structure.

In one embodiment, the ether compound includes a dialkyl ether of a glycol represented by formula (2), R ² O(C _n H _2n O) _x R ³ (2) (in formula (2), R ² and R ³ independently represents an alkyl group selected from the group consisting of methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl, and t-butyl, n is 2 Or 3, x is an integer from 1 to 4).

Examples of the dialkyl ether of the glycol represented by the formula (2) include ethylene glycol dimethyl ether, propylene glycol dimethyl ether, diethylene glycol dimethyl ether, dipropylene glycol dimethyl ether, and tripropylene glycol. Dimethyl ether, tripropylene glycol diethyl ether, tripropylene glycol di-n-butyl ether, tetraethylene glycol dimethyl ether, tetrapropylene glycol dimethyl ether, etc. From the viewpoint of decomposition and cleaning performance, ease of acquisition, price, etc., the dialkyl ether of the glycol represented by formula (2) is preferably diethylene glycol dimethyl ether or dipropylene glycol dimethyl ether. , since high etching speeds can be obtained with a wide range of compositions, dipropylene glycol dimethyl ether is more preferred.

When the aprotic solvent is 100% by mass, the content of the dialkyl ether of the glycol represented by the formula (2) is preferably 10 to 80% by mass, and 15 to 70% by mass. More preferably, it is 20 to 60 mass %. In other embodiments, when the aprotic solvent is 100% by mass, the content of the dialkyl ether of the glycol represented by formula (2) is preferably 0 to 60% by mass, so that It is more preferable that it is 3-50 mass %, and it is more preferable that it is 5-40 mass %.

In one embodiment, the ether compound includes a dialkyl ether represented by formula (3), R ⁴ OR ⁵ (3) (in the formula, R ⁴ and R ⁵ each independently represent an alkyl group with 4 to 8 carbon atoms).

The ether compound may include a dialkyl ether of a glycol represented by formula (2) and a dialkyl ether represented by formula (3). By combining two or more types of ether compounds with different polarities and using them in this way, the affinity for various adhesive surfaces can be effectively improved, and a composition with a wide application range can be obtained.

Examples of the dialkyl ether represented by formula (3) include dibutyl ether, dipentyl ether, dihexyl ether, diheptyl ether, dioctyl ether, butylhexyl ether, butyloctyl ether, and the like. . From the viewpoints of decomposition and cleaning performance, availability, price, etc., dibutyl ether is preferred as the dialkyl ether represented by formula (3).

When the aprotic solvent is 100% by mass, the content of the dialkyl ether represented by formula (3) is preferably 0 to 50% by mass, and more preferably 1 to 35% by mass. , it is better to set it to 2~30% by mass. By setting the content of the dialkyl ether represented by formula (3) to 0 mass % or more and 50 mass % or less, a higher etching rate can be obtained. In other embodiments, when the aprotic solvent is 100% by mass, the content of the dialkyl ether represented by formula (3) is preferably 30 to 70% by mass, and preferably 35 to 35% by mass. 65 mass % is more preferred, and 40 to 60 mass % is more preferred.

In one embodiment, the flash point of the ether compound is 21°C or higher. If the flash point is 21℃ or above (that is, it is not an ether compound equivalent to the Class 4, Class 1, hazardous substances, petroleum), compared with the use of tetrahydrofuran (THF; flash point -17℃; Class 4, Class 1, hazardous substances, petroleum) Category) and other circumstances, the requirements for equipment, operating environment, etc. in the manufacture and use of the composition can be reduced. For example, the flash points of diethylene glycol dimethyl ether, dipropylene glycol dimethyl ether and dibutyl ether are 51°C, 60°C and 25°C respectively. The flash point is measured by the TAG sealing method (JIS K 2265-1:2007).

<Composition ratio of N-substituted amide compound and ether compound> In one embodiment, when the aprotic solvent is 100% by mass, the content of the N-substituted amide compound is 10 to 90% by mass, and the content of the ether compound is 90 to 10% by mass. When the aprotic solvent is 100% by mass, the content of the N-substituted amide compound is preferably 15 to 85% by mass, and the content of the ether compound is preferably 85 to 15% by mass. The content of the N-substituted amide compound is preferably 25 to 65% by mass, and the content of the ether compound is preferably 75 to 35% by mass. In other embodiments, when the aprotic solvent is 100% by mass, the content of the N-substituted amide compound is 40 to 80% by mass, and the content of the ether compound is 60 to 20% by mass. % is better. By setting the content of the N-substituted amide compound and the ether compound to the above range, the quaternary alkylammonium fluoride and the hydrate can be uniformly dissolved in the composition, and various adhesive surfaces can be obtained. high etching speed.

In one embodiment, when the aprotic solvent is 100% by mass, the content of the N-substituted amide compound is 20 to 90% by mass, and the content of the dialkyl ether of the glycol represented by formula (2) is The amount is 10 to 80% by mass, and the content of the dialkyl ether represented by formula (3) is 0 to 30% by mass. Preferably, the content of the N-substituted amide compound is 25 to 80 mass %, the content of the dialkyl ether of the glycol represented by the formula (2) is 20 to 60 mass %, and the compound is preferably represented by the formula (3). The dialkyl ether content is 0 to 30% by mass. In other embodiments, when the aprotic solvent is 100% by mass, the content of the N-substituted amide compound is 20 to 90% by mass, and the dialkyl ether of the glycol represented by formula (2) is The content is 0 to 70% by mass, and the content of the dialkyl ether represented by formula (3) is 0 to 30% by mass. Preferably, the content of the N-substituted amide compound is 30 to 85% by mass, the content of the dialkyl ether of the glycol represented by the formula (2) is 3 to 50% by mass, and the compound is preferably represented by the formula (3). The dialkyl ether content is 0 to 30% by mass. Furthermore, in another embodiment, when the aprotic solvent is 100% by mass, the content of the N-substituted amide compound is 20 to 80% by mass, and the dialkyl group of the diol represented by formula (2) The content of the ether is 10 to 50% by mass, and the content of the dialkyl ether represented by formula (3) is 30 to 60% by mass.

＜Additives and other ingredients＞ The decomposition cleaning composition may contain additives such as antioxidants, surfactants, preservatives, and antifoaming agents as optional components within a range that does not significantly impair the effects of the present invention.

In one embodiment, the decomposition and cleaning composition contains substantially no protic solvent, or no protic solvent. For example, the content of the protic solvent in the composition can be 5 mass% or less, 3 mass% or less, or 1 mass% or less. The protic solvent that can be included in the composition may also be water derived from a hydrate of quaternary alkylammonium fluoride.

In one embodiment, the decomposition and cleaning composition substantially does not contain an aprotic solvent selected from ketones and esters, or does not contain an aprotic solvent selected from ketones and esters. For example, the content of the aprotic solvent selected from ketones and esters in the composition can be 1 mass% or less, 0.5 mass% or less, or 0.1 mass% or less.

<Bride ion concentration> In one embodiment, the bromide ion concentration in the decomposition cleaning composition is 100 mass ppm or less. The bromide ion concentration can be determined by ion chromatography using the conditions described in the examples. The bromide ion concentration in the decomposition cleaning composition is preferably 90 mass ppm or less, and further preferably 70 mass ppm or less. Even if the decomposition and cleaning composition is prepared with the same formulation, color deviation may occur. By setting the bromide ion concentration in the decomposition cleaning composition to 100 mass ppm or less, the color variation of the decomposition cleaning composition can be reduced.

[Method for manufacturing decomposition cleaning composition] The manufacturing method of the decomposition cleaning composition is not particularly limited. The decomposition and cleaning composition can be prepared by mixing an N-substituted amide compound, a quaternary alkylammonium fluoride or its hydrate, and other optional components.

Preferably, the decomposition and cleaning composition is prepared by mixing an N-substituted amide compound, a quaternary alkylammonium fluoride or its hydrate and other optional components in an inert gas environment. For example, in a glove box sealed with inert gas, use a stirrer to stir and mix the N-substituted amide compound, quaternary alkylammonium fluoride or the hydrate and other arbitrary components, so that the quaternary fluorinated alkyl A method of dissolving ammonium or its hydrate in a solvent. The inert gas system is preferably argon or nitrogen, and more preferably nitrogen.

The peroxide value (POV) of the N-substituted amide compound used in the production of the decomposition cleaning composition is preferably 10 meq/L or less. The peroxide value can be determined by iodine titration using the conditions described in the examples. The peroxide value of the N-substituted amide compound is preferably 7 meq/L or less, and more preferably 5 meq/L or less. The peroxide value of the N-substituted amide compound is an index indicating the degree of oxidation of the N-substituted amide compound. By using an N-substituted amide compound with a peroxide value of 10 meq/L or less, the content of N-substituted amide oxidation derivatives in the decomposition cleaning composition can be reduced, and a high etching rate can be obtained. Decompose the cleaning composition.

[How to use the decomposed cleaning composition] The decomposition and cleaning composition of the present disclosure can be used as a decomposition and cleaning composition of adhesive polymers contained in various adhesives. The adhesive polymer is not particularly limited as long as it can be cleaned using the decomposition cleaning composition of the present disclosure. In addition to the adhesive polymer, the adhesive system may contain a hardening agent, a hardening accelerator, a cross-linking agent, a surfactant, a leveling agent, a filler, etc. as optional components.

＜Adhesive polymer＞ In one embodiment, the adhesive polymer system contains Si-O bonds. The adhesive polymer becomes soluble in the solvent due to the cleavage of the Si-O bond due to the fluoride ions of the quaternary alkylammonium fluoride, thereby reducing the molecular weight or losing the cross-linked structure. The adhesive polymer can be removed from the surface of device wafers and the like.

The adhesive polymer containing Si-O bonds is preferably a polyorganosiloxane compound. Since the polyorganosiloxane compound contains a large number of siloxane bonds (Si-O-Si), the decomposition and cleaning composition can be used to effectively decompose and clean it. Examples of the polyorganosiloxane compound include polysilicone resins such as polysilicone elastomers, polysilicone gels, and MQ resins, as well as epoxy modified bodies, acrylic modified bodies, and methyl modified bodies thereof. Modified bodies such as acrylic acid modified body, amine modified body, thiol modified body, etc. The polyorganosiloxane compound may be a polysiloxane-modified polymer such as polysiloxane-modified polyurethane, polysiloxane-modified acrylic resin, or the like.

In one embodiment, the adhesive polymer is an addition-hardening polysilicone elastomer, polysilicone gel, or polysilicone resin. These addition-hardening polysiloxanes include polyorganosiloxanes containing ethylenically unsaturated groups (such as vinyl-terminated polydimethylsiloxane or vinyl-terminated MQ resin), and as a cross-linking agent Polyorganohydrogensiloxane (such as polymethylhydrogensiloxane) is hardened using a silicon hydrogenation catalyst such as a platinum catalyst.

In other embodiments, the adhesive polymer system may include a polyorganosiloxane selected from the group consisting of methyl-containing polyorganosiloxane, epoxy group-containing polyorganosiloxane, and phenyl-containing polyorganosiloxane. At least 1 species of the group. These polyorganosiloxanes are selected from the group consisting of polydimethylsiloxane, epoxy group-containing polydimethylsiloxane, and phenyl-containing polydimethylsiloxane. At least one of them is preferred.

The addition-hardening polysiloxane may also be selected from the group consisting of methyl-containing polyorganosiloxane, epoxy-containing polyorganosiloxane, and phenyl-containing polyorganosiloxane. At least 1 combination.

[How to clean adhesive polymers] The adhesive polymer located on a substrate such as a silicon wafer can be cleaned by various conventionally known methods using a decomposing cleaning composition. An example of a method for cleaning the adhesive polymer is to use a spin coater to rotate the base material at a specified speed and discharge the decomposed cleaning composition onto the base material in contact with the adhesive polymer. On the substrate (spin etching), spray the decomposition and cleaning composition on the adhesive polymer on the substrate (spray), and immerse the substrate with the adhesive polymer in a tank containing the decomposition and cleaning composition (immersion) wait. The temperature for decomposition and cleaning may vary depending on the type and amount of adhesive polymer on the substrate, but is generally 20°C to 90°C, preferably 40°C to 60°C. The time for decomposition and cleaning may vary depending on the type and amount of adhesive polymer on the substrate, but is generally 5 seconds to 10 hours, preferably 10 seconds to 2 hours. During decomposition and cleaning, ultrasonic waves can be applied to the decomposition and cleaning composition bath or substrate.

After decomposition and cleaning, the substrate can be rinsed with alcohol such as isopropyl alcohol (IPA), ion exchange water (DIW), etc., or by blowing with nitrogen, air, etc., or heating under normal pressure or reduced pressure. Wait for the substrate to dry.

[Manufacturing method of device wafer] In one embodiment, a method of manufacturing a device wafer includes using a decomposition cleaning composition to clean the adhesive polymer on the device wafer. After cleaning, the device wafer can be rinsed or dried as needed.

The method of manufacturing a device wafer may further include the following steps: forming a semiconductor device on a substrate such as a silicon wafer to obtain a device wafer; making the semiconductor device forming surface of the device wafer face the supporting wafer; placing the device The wafer and the support wafer are temporarily bonded with an adhesive containing an adhesive polymer; the device wafer is thinned by polishing the surface opposite to the device formation surface (back surface); and the support wafer is The circle is separated from the device wafer. The formation of the semiconductor device, the temporary bonding of the device wafer and the support wafer, the grinding of the backside of the device wafer, and the separation of the device wafer from the support wafer can be performed according to conventionally known methods and are not particularly limited. .

[Support wafer regeneration method] The decomposed cleaning composition can be used to regenerate support wafers used to manufacture device wafers. In one embodiment, the method for regenerating the support wafer includes using a decomposition cleaning composition to clean the adhesive polymer on the support wafer. After cleaning, the support wafer can be rinsed or dried as needed. [Example]

Hereinafter, the present invention will be described in more detail based on Examples and Comparative Examples, but the present invention is not limited by the Examples.

[Preparation of N-methylpyrrolidone (NMP)] As raw materials for the decomposition cleaning composition, a total of four types of NMP were prepared: unopened NMP (NMP-1) and NMP (NMP-2 to NMP-4) whose contact time with air after opening was changed in three stages. The peroxide values of NMP-1 to NMP-4 and the concentration of N-methylsuccinimide (NMS) were measured according to the following procedures.

[Measurement of peroxide value of NMP by iodine titration] In a 200 mL conical beaker, add 25 mL of a mixed solution of chloroform and acetic acid (chloroform: acetic acid = 2:3 (volume ratio)). Use a quantitative pipette to add 10 mL of NMP to the mixed solution and mix. Furthermore, 1.0 mL of saturated aqueous potassium iodide solution (30 g of potassium iodide/20 mL of distilled water) was added to the mixed solution, and the resulting solution was left to stand in a dark place for 10 minutes to allow the peroxide and iodide ions in the NMP to dissolve. react fully.

The mixed solution was taken out from the dark place, and 30 mL of distilled water and 8 mL of 1% starch aqueous solution were added to the mixed solution to obtain a sample for titration. Using a 2 mL microdropper, drop 0.01 M sodium thiosulfate aqueous solution (Kanto Chemical Co., Ltd.) into the titration sample until the color of the mixed solution becomes colorless and transparent. The volume of the dropped 0.01M sodium thiosulfate aqueous solution was taken as V (mL), and the peroxide value (POV) was calculated according to the following formula.

[Measurement of NMS concentration in NMP analyzed by GC] The concentration of NMS contained in NMP-1 to NMP-4 was measured according to the gas chromatography method under the following conditions. Gas chromatography analyzer: GC-17A (Shimadzu Corporation) Column: Agilent J&W GC column DB-WAX (Agilent Technologies Co., Ltd.), inner diameter 0.32mm, length 60m Column temperature: maintain at 140°C for 13 minutes → heat up at 20°C/min → 250°C Detector: FID

The peroxide values and NMS concentrations of NMP-1 to NMP-4 are shown in Table 1.

[Preparation of TBAF] As raw materials for the decomposition and cleaning composition, prepare two types of commercially available tetrabutylammonium fluoride trihydrate (TBAF·3H ₂ O) with a purity of 98%. The concentration of bromide ions contained in these TBAF·3H ₂ O was measured according to the following procedure.

[Measurement of bromide ions contained in TBAF・3H ₂ O] In a nitrogen atmosphere, 20 mg of TBAF・3H ₂ O was weighed as a sample and placed in a sample combustion device AQF-100 (Nittoseiko Analytech Co., Ltd.). Combustion decomposition is carried out by heating to 900°C under oxygen flow while ventilating water vapor.

The bromine contained in the sample is absorbed by bubbling the gas generated by combustion decomposition into 5 mL of absorption liquid. The absorbent solution is prepared according to the following procedure. Dissolve 10.6 g of sodium carbonate (special grade, Kanto Chemical Co., Ltd.) into ion-exchange water. The obtained solution was placed in a 100 mL measuring bottle and diluted to prepare a 1M Na ₂ CO ₃ aqueous solution. Add 10 mL of 1M Na ₂ CO ₃ aqueous solution, 1.5 mL of hydrogen peroxide water (for atomic absorption analysis, Kanto Chemical Co., Ltd.), and 5 mL of 1000 μg/mL phosphate ion standard solution (Kanto Chemical Co., Ltd.) into In a 500mL measuring bottle, dilute to 500mL with ion-exchange water to prepare an absorption solution. The concentration of the components in the absorption liquid is as follows. Na ₂ CO ₃ : 20mM Hydrogen peroxide: 1.5mL/500mL PO ₄ ^3- : 10μg/mL

The bromide ions contained in the obtained absorption liquid were analyzed by ion chromatography and measured under the following conditions. Ion chromatography analysis device: DIONEX ICS-1600 (Thermo Scientific Co., Ltd.) Eluate: 2.7mM Na ₂ CO ₃ +0.3mM NaHCO ₃ columns: DIONEX AG12A/AS12A (Thermo Scientific Co., Ltd.), 4mm inner diameter tube Column temperature: 30℃ Flow rate: 1.5mL/min Injection volume: 100μL Detector: Conductivity detector

The bromide ions contained in TBAF·3H ₂ O are calculated by dividing the amount of bromide ions in the absorbing liquid by the amount of TBAF·3H ₂ O. The bromide ion concentrations of the two types of commercially available TBAF・3H ₂ O are 10 ppm by mass and 1000 ppm by mass respectively. Hereinafter, TBAF・3H ₂ O with a bromide ion concentration of 10 ppm by mass is labeled as “TBAF-Br10”, and TBAF・3H ₂ O with a bromide ion concentration of 1000 ppm by mass is labeled as “TBAF-Br1000”.

[Preparation of decomposition cleaning composition] Use NMP-1 to NMP-4, as well as TBAF-Br10 and TBAF-Br1000 to prepare a decomposition and cleaning composition.

[Example 1] In a glove box sealed with nitrogen, put 4.748g of TBAF-Br1000 into a 125mL polyethylene container, followed by 35.157g of NMP-1 and 3.504g of dipropylene glycol dimethyl ether (DPGDME). , 6.598g of dibutyl ether (DBE), and mix to dissolve TBAF-Br1000. In this manner, a decomposition and cleaning composition of 7.7% by mass TBAF mixed solvent containing 95 mass ppm (calculated value) of bromide ions and with a mass ratio of NMP:DPGDME:DBE of 0.777:0.077:0.146 was prepared. The decomposed and washed composition was transferred to a 50 mL glass colorimetric tube and sealed with nitrogen, and then the colorimetric tube was sealed with a glass stopper.

[Example 2] In a glove box sealed with nitrogen, add 3.561g of TBAF-Br1000 and 1.189g of TBAF-Br10 into a 125mL polyethylene container, followed by 35.147g of NMP-1, 3.502g of DPGDME, 6.598g of DBE was mixed to dissolve TBAF-Br1000 and TBAF-Br10. In this manner, a decomposition and cleaning composition of 7.7 mass % TBAF mixed solvent containing 71 mass ppm (calculated value) of bromide ions and with a mass ratio of NMP:DPGDME:DBE of 0.777:0.077:0.146 was prepared. The decomposed and washed composition was transferred to a 50 mL glass colorimetric tube and sealed with nitrogen, and then the colorimetric tube was sealed with a glass stopper.

[Examples 3 to 15, Comparative Examples 1 to 6] Except setting the composition as described in Table 2, a decomposition cleaning composition was prepared in the same procedure as in Example 1 or 2.

[Preparation of silicon wafer test piece with adhesive layer containing polyorganosiloxane compound] By spin coating, the addition-hardening polysiloxane resin was coated on a 12-inch (300mm) silicon wafer (thickness 770μm) so that the dry film thickness became 110μm. Thereafter, the adhesive layer was formed on the silicon wafer after heating at 140° C. for 15 minutes and 190° C. for 10 minutes on a hot plate. The silicon wafer having the adhesive layer containing the polyorganosiloxane compound was divided into 1.5 cm×1.5 cm size to serve as test pieces.

[Cleaning test] Place a 50cc spiral vial on top of the magnetic stirrer. Put 15.0 mL of decomposition and cleaning composition and stirrer into the spiral vial. One test piece was immersed in the decomposed and washed composition, and the stirring bar was rotated at 900 rpm for 3 minutes at room temperature (25° C.). After immersion, use tweezers to take out the test piece and rinse thoroughly with isopropyl alcohol (IPA) in a washing bottle. After drying the test piece by blowing nitrogen gas, the thickness of the center portion of the test piece was measured using a micrometer. The etching rate (ER) of the decomposition cleaning composition was calculated by dividing the difference in thickness of the test piece before and after immersion by the immersion time in the decomposition cleaning composition. Etching rate (ER) (μm/min) = [(Thickness of test piece before immersion - Thickness of test piece after immersion, cleaning, and drying) (μm)]/Immersion time (3 minutes)

Table 2 shows the compositions and evaluation results of Examples 1 to 15 and Comparative Examples 1 to 6.

[Example 16 and Comparative Example 7] The same procedure as in Example 1 was used to prepare a decomposition and cleaning composition of a 5 mass % TBAF mixed solvent with a mass ratio of NMP:DPGDME of 0.764:0.236. The prepared decomposition and cleaning composition was stored in a nitrogen atmosphere for 16 months, and the decomposition and cleaning composition of Example 16 with an N-methylsuccinimide (NMS) concentration of 550 ppm or less was obtained. The decomposition and cleaning composition prepared in the same way was stored in an air environment for 16 months, and the decomposition and cleaning composition of Comparative Example 7 in which the concentration of N-methylsuccinimide (NMS) exceeded 550 ppm was obtained.

The decomposition and cleaning compositions of Example 16 and Comparative Example 7 were subjected to ¹⁹ F NMR measurement. Figure 1 shows the decomposition and cleaning compositions of Example 16 (marked as N ₂ ) and Comparative Example 7 (marked as Air), and tetrabutylammonium difluoride (marked as TBAHF2, manufactured by Sigma-Aldrich Japan Contract Co., Ltd.) ^19F NMR spectrum. The high-intensity peak near -115 ppm observed in the decomposition cleaning composition of Example 16 is attributed to the fluoride ion (F ^- ) derived from tetrabutylammonium fluoride. In the decomposition cleaning composition of Comparative Example 7, the peak near -115 ppm disappeared, and instead the area of the peak near -148 to -150 ppm attributed to difluoride ions (HF ₂ ^- ) increased. [Industrial Applicability]

The decomposition cleaning composition of the present invention can be suitably used to remove residues of adhesives (especially adhesives containing polyorganosiloxane compounds as adhesive polymers) used in thinning processes for semiconductor wafers. It is used for decomposing and cleaning materials from device wafers.

[Fig. 1] ¹⁹ F NMR spectra of the decomposition and cleaning compositions of Example 16 (labeled as N ₂ ) and Comparative Example 7 (labeled as Air), and tetrabutylammonium difluoride (labeled as TBAHF2).

Claims (17)

A method for producing a decomposition and cleaning composition containing (A) an N-substituted amide compound in which two alkyl groups are bonded to a amide nitrogen atom as an aprotic solvent, and (B) quaternary fluorine A method for producing a decomposition and cleaning composition for an alkylammonium chloride or its hydrate, which includes adding two hydrogen atoms to the carbon atom at the alpha position of the amide nitrogen atom of the N-substituted amide compound (A). The above-mentioned (A) N is mixed in an inert gas atmosphere so that the content of the N-substituted amide oxidation derivative of a compound whose atoms are substituted by side oxygen groups becomes 550 mass ppm or less relative to the decomposition cleaning composition. -Substituted amide compound, and the aforementioned (B) quaternary alkylammonium fluoride or the hydrate. The method for producing a decomposition cleaning composition according to claim 1, wherein the (A) N-substituted amide compound used in the mixing has a peroxide value (POV) of 10 meq/L or less. The method for producing a decomposition cleaning composition according to claim 1 or 2, wherein the inert gas is nitrogen. The method for producing a decomposition and cleaning composition according to claim 1 or 2, wherein the bromide ion concentration in the decomposition and cleaning composition is 100 ppm by mass or less. The method for producing a decomposition cleaning composition according to claim 1 or 2, wherein the decomposition cleaning composition further contains (C) an ether compound as an aprotic solvent. The method for producing a decomposition and cleaning composition according to claim 5, wherein the total content of the (A) N-substituted amide compound and the (C) ether compound in the decomposition and cleaning composition is 70 to 99.99 mass. %. The method for producing a decomposition cleaning composition according to claim 1 or 2, wherein the (A) N-substituted amide compound is a 2-pyrrolidone derivative compound represented by formula (1),

(In formula (1), R ¹ represents an alkyl group having 1 to 4 carbon atoms), the aforementioned N-substituted amide oxidation derivative is an N-substituted succinimide compound represented by formula (4),

(In formula (4), R ¹ represents an alkyl group having 1 to 4 carbon atoms). The method for producing a decomposition cleaning composition according to claim 7, wherein the (A) N-substituted amide compound is a 2-pyrrolidone derivative compound in which R ¹ in the formula (1) is methyl or ethyl. The method for producing a decomposition cleaning composition according to claim 5, wherein the ether compound (C) contains a dialkyl ether of a glycol represented by the formula (2), R ² O (C _n H _2n O) _x R ³ (2) (In formula (2), R ² and R ³ independently represent selected from methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl, and t- Alkyl group of the group consisting of butyl group, n is 2 or 3, x is an integer from 1 to 4). The method for producing a decomposition cleaning composition according to claim 9, wherein the dialkyl ether of the glycol is dipropylene glycol dimethyl ether. The method for producing a decomposition cleaning composition according to claim 5, wherein the ether compound (C) includes a dialkyl ether represented by the formula (3), R ⁴ OR ⁵ (3) (in the formula, R ⁴ and R ⁵ Each independently represents an alkyl group with 4 to 8 carbon atoms). The method for producing a decomposition and cleaning composition according to claim 11, wherein the dialkyl ether is dibutyl ether. The method for producing a decomposition cleaning composition according to claim 1 or 2, wherein the aforementioned (B) quaternary alkylammonium fluoride is a tetraalkylammonium fluoride represented by R ⁶ R ⁷ R ⁸ R ⁹ N ⁺ F ^- , R ⁶ ~ R ⁹ are each independently an alkyl group selected from the group consisting of methyl, ethyl, n-propyl, isopropyl, and n-butyl. The method for producing a decomposition cleaning composition according to claim 1 or 2, wherein the content of the aforementioned (B) quaternary alkylammonium fluoride is 0.01 to 10% by mass. The method for producing a decomposing cleaning composition according to claim 1 or 2, wherein the decomposing cleaning composition is a decomposing cleaning composition of an adhesive polymer. The method for producing a decomposition cleaning composition according to claim 15, wherein the adhesive polymer is a polyorganosiloxane compound. A method of cleaning an adhesive polymer on a base material using a decomposition and cleaning composition produced by the method of producing a decomposition and cleaning composition according to claim 1 or 2.

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