JP4731406B2 - Release agent composition - Google Patents

Description

  The present invention relates to a stripper composition used for removing a metal residue generated from a resist residue and / or a metal wiring generated in the process of manufacturing a semiconductor element, and a method for manufacturing a semiconductor element using the same.

  Generally, a semiconductor element includes a semiconductor substrate made of silicon, a plurality of wirings arranged on one main surface side of the semiconductor substrate, electrodes, and through holes or via holes (including filled vias) that connect the plurality of wirings to each other. ), And contact holes or the like that connect the wiring and elements such as transistors are integrated. Hereinafter, through holes, via holes, and contact holes may be collectively referred to as “interlayer connection conductors”.

  By the way, the formation process of wiring, electrodes, interlayer connection conductors and the like in the manufacture of semiconductor elements is performed by a film formation method such as a PVD (physical vapor deposition) method or a CVD (chemical vapor deposition) method, respectively. And a step of forming a conductive film. Further, a step of forming a resist pattern on the conductive film or the insulating film by lithography, and using the resist pattern as a mask, the insulating film and / or the conductive film is selectively etched to form wiring layers, electrodes, and interlayer connection conductors. A step of forming a hole (a hole before being filled with a conductive material) is also included.

  After the formation of wiring, electrodes, holes for interlayer connection conductors, and the like, the resist pattern is removed by ashing using oxygen gas or the like. After the ashing process, a cleaning process including a residue peeling process and a rinsing process is performed. In the residue peeling step, the resist residue and etching residue that could not be removed by ashing are peeled off by a cleaning agent (also called a release agent composition). In the rinsing step, the release agent composition is removed by rinsing. Note that the etching residue subjected to the ashing treatment may include a metal element derived from a conductive film or the like. Hereinafter, the residue containing the metal element may be referred to as a “metal-containing residue”. Resist residues, metal-containing residues, and other residues may be collectively referred to simply as “residues”.

  By the way, if the residue is not completely removed even after the cleaning process, the connection resistance may increase. This is because these residues often contain materials with low electrical conductivity. Therefore, the residue needs to be removed appropriately.

  On the other hand, it is necessary to suppress corrosion (such as discoloration or dissolution of the metal surface) of the metal wiring or the like by the release agent composition. This is because the resistance increases when the degree of corrosion is large. In addition, from the viewpoint of environmental protection, it is necessary to consider the load that the release agent composition gives to the environment.

Under such a background, conventionally, a cleaning liquid containing a fluorine-containing compound (for example, see Patent Document 1) has been often used for peeling off the residue. In addition, water-based cleaning agents have been proposed that are particularly focused on corrosion inhibition and environmental conservation of wiring containing aluminum (Al) (see, for example, Patent Documents 2 and 3).
JP 2004-94203 A JP 2001-168015 A Japanese Patent Application Laid-Open No. 11-131093

  By the way, the recent manufacture of semiconductor devices tends to produce a variety of products in small quantities. Therefore, the cost is reduced by increasing the diameter of the silicon wafer and increasing the number of semiconductor elements obtained by one manufacturing.

  However, the batch-type peeling method (a method in which peeling processing is performed on about 25 silicon wafers at a time) that has been conventionally employed in the manufacturing process of semiconductor elements is difficult to cope with high-mix low-volume production. In addition, an increase in the size of transfer equipment accompanying the increase in the diameter of silicon wafers has become a new issue.

  In order to solve such a problem, there is an increasing number of cases where a single wafer peeling method (usually a method in which a silicon wafer is peeled in units of two to several in some cases) is employed. Under such circumstances, in the case of adopting a batch-type peeling method, particularly a single-wafer type peeling method, it is desired that the residue can be suitably peeled off under low-temperature and short-time peeling conditions.

  However, when the cleaning agent (peeling agent composition) described in Patent Documents 1 to 3 is used, the residue cannot be suitably peeled off under peeling conditions at a low temperature for a short time.

  In the present invention, regardless of which stripping method is employed, a residue (for example, an oxidation product containing Al, copper (Cu), and Ti (titanium)) is preferably used under stripping conditions at a low temperature for a short time. A stripper composition that can be peeled off, has a high corrosion-inhibiting effect on wiring (particularly Al-containing wiring), and has a low environmental impact, and is particularly suitable for the single-wafer type peeling method, and manufacture of a semiconductor element using the same It aims to provide a method.

  The release agent composition of the present invention is a release agent composition used in the process of manufacturing a semiconductor element including wiring, and includes an organic amine, an organic phosphonic acid, a linear sugar alcohol, and water, and is 20 ° C. PH at 9-13.

  The release agent composition of the present invention is a release agent composition used in the production process of a semiconductor element including wiring, and an organic amine, an organic phosphonic acid, and a linear sugar alcohol are added to water, and 20 It is a release agent composition obtained by adjusting the pH at 9 ° C. to 9 to 13.

  A method for manufacturing a semiconductor element of the present invention is a method for manufacturing a semiconductor element including a semiconductor substrate and wiring, wherein a metal layer and a resist pattern are formed in this order on one main surface side of the semiconductor substrate, Etching the metal layer using a resist pattern as a mask to form a wiring, a ashing process for ashing the resist pattern, and a residue peeling for removing residues remaining in the vicinity of the wiring after the ashing process In the residue removal step, the residue is removed using the release agent composition of the present invention.

  According to the present invention, the effect of inhibiting corrosion (corrosion resistance) on metal wiring (particularly metal wiring containing Al) is high, and residues (for example, Al, copper (Cu), and Ti (titanium) are subjected to stripping conditions at a low temperature for a short time. The release product composition can be suitably peeled off and the load on the environment is small, and a semiconductor device manufacturing method using the same can be provided.

  The release agent composition of the present embodiment is suitable for removing a residue containing Al, W (tungsten), Cu, or Ti, but is particularly suitable for removing a residue containing Al, Cu, or Ti. Note that these metal elements may be contained in the residue in the form of a compound such as an oxide, or may be contained in the form of an alloy. In addition, the release agent composition of the present embodiment is particularly suitable for use in the process of manufacturing a semiconductor element having a metal wiring containing Al because it has excellent corrosion resistance to the metal wiring containing Al.

  The release agent composition of the present embodiment has an organic amine content of 0.2 to 30% by weight, an organic phosphonic acid content of 0.05 to 10% by weight, and a linear sugar alcohol content of 0.1. The content of water is preferably 10 to 10% by weight and the content of water is 50 to 99.65% by weight. This release agent composition comprises an organic amine (blending amount: 0.2 to 30% by weight), an organic phosphonic acid (blending amount: 0.05 to 10% by weight), and a linear sugar alcohol (blending amount: 0.00%). 1 to 10% by weight) can be added to water (blending amount: 50 to 99.65% by weight) and adjusted so that the pH at 20 ° C. is 9 to 13.

  The stripping composition of the present invention can be used in a residue stripping method. An example of this residue peeling method is a wiring formation step of forming a wiring by forming a metal layer and a resist pattern in this order on one main surface side of a semiconductor substrate and etching the metal layer using the resist pattern as a mask. And an ashing process (first ashing process) for ashing the resist pattern and a residue peeling process (first residue peeling process) for removing residues remaining in the vicinity of the wiring after the ashing process. In this first residue peeling step, the residue is removed using the release agent composition of the present invention.

  The “residue remaining in the vicinity of the wiring” includes a metal-containing residue and / or a resist residue attached to the surface (for example, side surface) of the wiring or a layer adjacent to the wiring.

  A preferred example of the residue peeling method or a preferred example of the semiconductor element manufacturing method is that after the first residue peeling step, an insulating layer that covers the wiring from the opposite side of the semiconductor substrate side is formed, and a resist pattern is formed on the insulating layer. Forming and etching the insulating layer using the resist pattern as a mask to form a hole, a second ashing process for ashing the resist pattern on the insulating layer, and a hole remaining after the second ashing process And a second residue peeling step for removing the residue. Also in this second residue stripping step, the residue is removed using the stripping composition of the present embodiment.

  Here, the “residue remaining in the vicinity of the hole” includes a metal-containing residue remaining in the hole, a metal-containing residue and a resist residue remaining on the insulating layer near the hole.

  In a preferred example of the residue peeling method or a preferred example of the semiconductor element manufacturing method, for example, at least one of the barrier film in contact with the wiring before and after formation of the wiring containing Al or the like Form. The barrier film includes, for example, TiN.

  In a preferred example of the residue peeling method or a preferred example of the semiconductor element manufacturing method, the residue is removed by a single wafer peeling method in the first residue peeling step or the second residue peeling step. Specifically, for example, silicon wafers that become semiconductor substrates by being divided are usually placed one by one in a spin coater. Then, it is preferable to drop the release agent composition from above the silicon wafer while rotating the silicon wafer. According to this method, the amount of the release agent composition used can be reduced, and a release agent composition having a constant concentration is always applied to the structure (a structure including a wiring and a semiconductor substrate, or an insulating film through the wiring). To the structure having the reached hole).

  A preferred example of the residue peeling method or a preferred example of the method for manufacturing a semiconductor device includes a rinsing step performed after the first residue peeling step or the second residue peeling step. In the rinsing process, a structure including a wiring and a semiconductor substrate or a structure having a hole reaching the wiring through the insulating film is rinsed with water, and the release agent composition attached to these structures is removed. .

  The present invention will be described in detail below.

  In the release agent composition of the present embodiment, the organic amine has an action of dissolving the residue that could not be removed by ashing. The organic phosphonic acid has an anticorrosive action against metals. The linear sugar alcohol has an anticorrosive action against metals, particularly Al. In the release agent composition of this embodiment, since water is used as a solvent for dissolving them, the load on the environment is small.

  The water contained in the release agent composition may be, for example, any of ultrapure water, pure water, ion-exchanged water, distilled water, etc. Among them, ultrapure water, pure water and Ion exchange water is preferred, ultrapure water and pure water are more preferred, and ultrapure water is even more preferred. Here, pure water and ultrapure water are obtained by passing tap water through activated carbon, ion-exchange treatment, and further distilling, irradiating the light of a predetermined ultraviolet germicidal lamp or passing through a filter as necessary. Say. For example, the electrical conductivity at 25 ° C. is often 1 μS / cm or less for pure water and 0.1 μS / cm or less for ultrapure water.

  The content of water in the release agent composition is determined from the viewpoint of environmental considerations such as the stability of the release agent composition, workability, and waste liquid disposability. From the viewpoint of achieving both reduction in oxygen demand and pH stability, it is preferably 50 to 99.65% by weight in the total amount of the release agent composition. Since it is preferable that there are few active ingredients other than water, 80 to 98 weight% is more preferable and, as for content of water in a peeling agent composition, 93 to 97 weight% is further more preferable. In the present invention, the COD of the release agent composition is measured based on JIS K 0102 20

  Examples of the organic amine contained in the release agent composition include aliphatic amines, aromatic amines, and cyclic amines, and organic amines having 1 to 4 nitrogen atoms in one molecule are particularly preferable. Specific examples include aliphatic amines having one nitrogen atom in one molecule such as monoalkylamines having 1 to 20 carbon atoms, dialkylamines having 2 to 22 carbon atoms and trialkylamines having 3 to 24 carbon atoms; benzyl Aromatic amines having one nitrogen atom in one molecule such as amine, dibenzylamine, tribenzylamine, 1-aminonaphthalene, alkylbenzylamine; ethylenediamine, triethylenediamine, 1,2-propanediamine, 1,3- Fat having two nitrogen atoms in one molecule such as propanediamine, 1,6-hexanediamine, 1,2-cyclohexanediamine, 1,3-diaminoxylene, 1,3-bisaminocyclohexane, tetramethylhexamethylenediamine Group amines; fats having three nitrogen atoms in one molecule such as diethylenetriamine An amine; an aliphatic amine having 4 nitrogen atoms in one molecule such as triethylenetetramine; a compound in which an alkylene oxide having 2 to 4 carbon atoms is added to the organic amine having 1 to 4 nitrogen atoms in one molecule ( Monoethanolamine, monopropanolamine, monoisopropanolamine, diethanolamine, methylmonoethanolamine, butylmonoethanolamine, triethanolamine, dimethylmonoethanolamine, methyldiethanolamine, 2-amino-1-propanol, 1-amino-2- Alkanolamines such as propanol; alkoxyalkylamines such as 2-methoxyethylamine, 2-ethoxyethylamine, 3-methoxypropylamine, 3-ethoxypropylamine; 2- (2-aminoethoxy) ethanol, 2 -Alkoxyalkanolamines such as (2-aminoethoxy) propanol)); cyclic amines having 1 to 3 nitrogen atoms in one molecule such as piperazine, piperidine, morpholine, 1,2,4-triazole Is mentioned. These organic amines may be used alone or in combination of two or more.

  Of these organic amines, aliphatic amines that have excellent releasability to residues, excellent corrosion resistance to metal wiring, and high environmental compatibility such as biodegradability are preferable, and have two nitrogen atoms in one molecule. Aliphatic amines are more preferred, 1,2-propanediamine and 1,3-propanediamine are more preferred, and 1,3-propanediamine is particularly preferred.

  The content of the organic amine in the release agent composition is from the viewpoint of satisfying the waste liquid treatment property, the release property to the residue in a short time at a low temperature, the anticorrosion property to the metal wiring at the time of rinsing, the reduction of COD, and the pH stability. It is preferable that it is 0.2-30 weight in release agent composition. Furthermore, 0.2 to 4 weight% is preferable and 0.5 to 4 weight% is more preferable.

  Examples of the organic phosphonic acid contained in the release agent composition include methyldiphosphonic acid, aminotri (methylenephosphonic acid), ethylidenediphosphonic acid, 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP), and 1-hydroxypropylidene. -1,1-diphosphonic acid, 1-hydroxybutylidene-1,1-diphosphonic acid, ethylaminobis (methylenephosphonic acid), 1,2-propylenediaminetetra (methylenephosphonic acid), dodecylaminobis (methylenephosphonic acid) ), Nitrotris (methylenephosphonic acid), ethylenediaminebis (methylenephosphonic acid), ethylenediaminetetra (methylenephosphonic acid), hexenediaminetetra (methylenephosphonic acid), diethylenetriaminepenta (methylenephosphonic acid), cyclohexanediaminete And la (methylenephosphonic acid). These organic phosphonic acids may be used alone or in combination of two or more.

  Of these organic phosphonic acids, aminotri (methylenephosphonic acid) and 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP), which have excellent anticorrosive properties against metal wiring, are preferred.

  The content of the organic phosphonic acid in the release agent composition is from the viewpoint of ensuring excellent corrosion resistance to metal wiring, from the viewpoint of environmental considerations such as waste liquid treatment, from the viewpoint of reducing COD, and from the viewpoint of ensuring pH stability. Therefore, the content is preferably 0.05 to 10% by weight in the release agent composition. Furthermore, 0.05 to 6 weight% is preferable and 0.2 to 3 weight% is more preferable.

  As the linear sugar alcohol contained in the release agent composition, tetritol, pentitol, hexitol, heptitol, octitol, nonitol, etc. from the standpoint of achieving both the peelability of the residue and the anticorrosive properties against metal wiring (particularly Al-containing wiring) Is mentioned. Examples of tetritol include threitol and erythritol, and examples of pentitol include arabitol, ribitol (adonitol), xylitol, and lyxitol. Examples of hexitol include sorbitol, mannitol, iditol, glycol, allozulcitol (allitol) and the like. These linear sugar alcohols may be used alone or in combination of two or more. Among these, at least one selected from the group consisting of D-sorbitol and D-mannitol is preferable.

  The content of the linear sugar alcohol in the release agent composition is preferably 0.1 to 10% by weight in the release agent composition from the viewpoints of coexistence of release properties and anticorrosion properties and environmental conservation. 5 to 10 weight% is more preferable, 1 to 7 weight% is further more preferable, and 1.5 to 5 weight% is still more preferable.

  The weight ratio of organic amine to organic phosphonic acid in the stripper composition (organic amine / organic phosphonic acid) is 0 from the viewpoint of satisfying the peelability of the residue, the corrosion resistance of the metal wiring, the reduction of COD, and the pH stability. 0.5 / 1 to 7.5 / 1 is preferable, 1/1 to 3.5 / 1 is more preferable, and 1/1 to 2.2 / 1 is further preferable.

  The weight ratio of linear sugar alcohol to the total amount of organic amine and organic phosphonic acid [linear sugar alcohol / (organic amine + organic phosphonic acid)] is a viewpoint that achieves both the peelability of the residue and the anticorrosive property to the metal wiring. Therefore, 1 / 0.03 to 1/36 is preferable, 1 / 0.05 to 1/17 is more preferable, and 1 / 0.3 to 1 / 0.8 is more preferable.

  The pH of the release agent composition at 20 ° C. is 9 to 13 from the viewpoint of achieving both peelability to the residue and anticorrosion properties to the metal wiring, but 10 to 12 is preferable and 10 to 11.5 is more preferable.

  As the pH adjuster, for example, inorganic acids such as phosphonic acid, sulfuric acid, nitric acid, phosphoric acid and hydrochloric acid, organic acids such as acetic acid and carboxylic acid (oxalic acid and the like), and acidic substances such as alkyl sulfuric acid may be used.

  The release agent composition may contain a water-soluble organic solvent, a surfactant, a fluorine-containing compound and the like as optional components as long as the effects of the present invention are not hindered.

  Examples of the water-soluble organic solvent include polyhydric alcohols or glycol ethers. Examples of polyhydric alcohols include γ-butyrolactone, N-methylpyrrolidone, dimethylformamide, dimethyl sulfoxide, ethylene glycol, and propylene glycol. Examples of glycol ethers include ethylene glycol monobutyl ether and diethylene glycol monobutyl ether. These may be used alone or in combination of two or more. Among these, ethylene glycol and diethylene glycol monobutyl ether are preferable, and diethylene glycol monobutyl ether is more preferable from the viewpoint of further increasing the permeability of the release agent composition to the residue, wettability to the wafer, and the like. In the present application, the water-soluble organic solvent means a solvent having a solubility in water at 20 ° C. of at least 1.5% by weight.

  The surfactant may be any of an anionic surfactant, a cationic surfactant, an amphoteric surfactant, a nonionic surfactant, and the like. Examples of the anionic surfactant include fatty acid salts, alkyl sulfate esters, alkyl benzene sulfonates, polyoxyethylene alkyl ether sulfates, dialkyl sulfosuccinic acids, and the like. Examples of the cationic surfactant include alkylamine acetate and quaternary ammonium salt. Examples of amphoteric surfactants include alkyldimethylaminoacetic acid betaines and alkyldimethylamine oxides. Examples of the nonionic surfactant include glycerin fatty acid ester, propylene glycol fatty acid ester, polyoxyethylene alkyl ether, polyoxyethylene polyoxypropylene ether, and the like.

  Examples of the fluorine-containing compound include hydrofluoric acid, ammonium fluoride, ammonium hexafluorosilicate, ammonium hexafluorophosphate, alkylamine hydrofluoride, alkanolamine hydrofluoride, and tetraalkylammonium fluoride. It is done.

  There is no restriction | limiting in particular about the adjustment method of the peeling agent composition of this embodiment. For example, an organic amine, an organic phosphonic acid, a linear sugar alcohol, and the above optional component may be added to water and mixed. Furthermore, what is necessary is just to adjust a pH to 9-13 by adding a pH adjuster as needed. A known method may be adopted as the mixing method. There is no restriction | limiting in particular also about the order etc. which dissolve each component in water. The release agent composition of the present embodiment thus obtained has a high corrosion-inhibiting effect on metal wiring and the like, although the residue can be suitably peeled off at a low temperature in a short time. In addition, since it contains a linear sugar alcohol, the peelability and the anticorrosive property are balanced for a relatively long time within the peeling conditions at a low temperature for a short time. Therefore, if the stripping composition of this embodiment is used, it becomes easy to manage stripping conditions (particularly stripping processing time, especially stripping processing time when stripping is performed by a single-wafer stripping method).

  In addition, although content of each component demonstrated in the above is content at the time of use, the stripping composition of this embodiment is supplied and used in the state concentrated in the range which does not impair the stability. Sometimes diluted with water or the like may be used.

  Next, an example of a residue peeling method using the release agent composition of the present embodiment or an example of a method for manufacturing a semiconductor element will be described with reference to FIGS. 1A to 3D.

1A to 3D, the insulating layer 2 is disposed on the semiconductor substrate 1 so as to simplify the drawings. However, actually, an element isolation film (for example, SiO ₂ ), another wiring, another insulating layer, an interlayer connection conductor, a gate electrode constituting a transistor, or the like is disposed between the semiconductor substrate 1 and the insulating layer 2. The semiconductor substrate 1 includes an impurity diffusion region doped with impurities. Further, the semiconductor substrate shown in FIGS. 1A to 3D is in a state of constituting a part of the silicon wafer before dicing.

(Al wiring formation)
First, as shown in FIG. 1A, for example, an insulating layer 2 (for example, SiO ₂ ) is formed on one main surface side of the semiconductor substrate 1, and a barrier layer 3 (for example, TiN) is formed on the insulating layer 2. . Next, an Al layer 4 is formed on the barrier layer 3, and a barrier layer 5 (for example, TiN) is formed on the Al layer 4. Next, a resist pattern 6 a is formed on the barrier layer 5. The insulating layer 2, the barrier layers 3, 5, and the Al layer 4 can all be formed by a CVD method. A conventionally known photoresist may be used as the material of the resist pattern 6a. The formation method is not particularly limited, and a conventionally known photolithography technique may be used.

  Next, using the resist pattern 6a as a mask, the barrier layers 3, 5 and the Al layer 4 are etched to form an Al wiring 4a as shown in FIG. 1B (wiring forming step). For the etching gas 7, for example, a chlorine-based gas may be used. In FIG. 1B, reference numeral 9a denotes an etching residue before the ashing process.

  Next, the resist pattern 6a is removed by ashing using oxygen gas 8 or the like (first ashing step). As shown in FIG. 1C, residue 9b adheres to the side surface of the Al wiring after the ashing process and the side surfaces of the barrier layers 3 and 5 adjacent to the Al wiring. The residue 9b contains Al, Ti, or the like.

  Next, the residue 9b is removed using the stripping composition of the present embodiment (see FIG. 1D, first residue stripping step). In this process, for example, as shown in FIG. 2, the silicon wafer 10 is placed in a spin coater 11, and while the silicon wafer 10 is rotated, the release agent composition 12 is applied from above to the wiring 4 a and the semiconductor substrate 1. This can be performed by dropping the structure 100 including the structure 100 (see FIG. 1D). The amount of the release agent composition 12 dropped is, for example, about 150 ml for the silicon wafer 10 having a diameter of about 200 mm. A rotation speed of about 150 rpm is appropriate.

  Next, the release agent composition attached to the structure 100 (see FIG. 1D) including the wiring 4a and the semiconductor substrate 1 is rinsed with water (rinsing step), and then dried by spraying nitrogen gas or the like. The rinsing method is not particularly limited, and a conventionally known method may be employed.

(Hole formation)
Next, as shown in FIG. 3A, after forming an insulating layer 15 that covers the wiring 4a from the opposite side of the semiconductor substrate 1, the insulating layer 15 is planarized by a CMP (chemical mechanical polishing) method or the like. Next, a resist pattern 6 b is formed on the planarized insulating layer 15. Next, as shown in FIG. 3B, the insulating layer 15 and the barrier film 5 are etched using the resist pattern 6b as a mask to form holes 17 reaching the wiring 4a (hole forming step). The material and the formation method of the resist pattern 6b may be the same as in the case of the resist pattern 6a, for example. As the etching gas 13, for example, a fluorine-based gas may be used. In FIG. 3B, reference numeral 16a denotes an etching residue before the ashing process.

  Next, the resist pattern 6b is removed by ashing using oxygen gas 14 or the like (second ashing step). As shown in FIG. 3C, the residue 16b adheres to the hole inner surface and the insulating layer 15 after ashing, but the residue 16b attached to the hole inner surface mainly includes a metal-containing residue containing Al and Ti, and the insulating layer 15 The residue 16b attached to the resist contains a resist residue.

  Next, the residue 16b is removed using the stripping composition of the present embodiment (see FIG. 3D, second residue stripping step). This process may be performed using, for example, the spin coater 11 shown in FIG. 2, and the dropping amount of the release agent composition 12 and the rotation speed may be the same as described above.

  Next, the structure 200 (see FIG. 3D) including the holes 17 and the semiconductor substrate 1 is rinsed with, for example, water to remove the release agent composition attached to the structure 200 (rinse process). After that, nitrogen gas or the like is blown onto the structure 200 and dried.

  Thus, in a preferable example of the residue peeling method of the present embodiment or a preferable example of the method of manufacturing a semiconductor element of the present embodiment, the residue remaining in the vicinity of the wiring containing Al can be suitably removed.

  In the method of removing the residue, in addition to the single wafer type using the above spin coater, a plurality of wafers (for example, about 25 wafers) to be processed are collectively immersed in the release agent composition at once, A method of performing a peeling process by swinging a jig or applying ultrasonic waves or jets to the release agent composition, a method of performing a release process by spraying or spraying a release agent composition on a wafer to be processed, and a process. A method of immersing a wafer to be removed in a release agent composition stirred by a paddle can be employed. Regardless of which method is employed, if the release agent composition of the present embodiment is used, the residue can be sufficiently removed in a short time at a low temperature, and thus energy saving and improvement in production efficiency can be realized.

  The temperature of the release agent composition during the release treatment is preferably 10 to 50 ° C., more preferably 20 to 50 ° C., more preferably 20 to 50 ° C. from the viewpoints of releasability with respect to residues, corrosion resistance to metal wiring, safety and workability. 40 ° C. is more preferable.

  The stripping treatment time is preferably 10 seconds or more and 5 minutes or less, particularly 0.5 minutes or more and 4 minutes or less in the single wafer peeling method from the viewpoints of peelability to residues, corrosion resistance to metal wiring, safety and operability. Is more preferable, 0.5 minutes or more and 3.5 minutes or less are more preferable, and 0.5 minutes or more and 3 minutes or less are still more preferable. In addition, in this application, the said peeling process time means immersion time, for example, when immersing a peeling object in a release agent composition, and when using the spin coater shown in FIG. It means the time from the moment when the release agent composition is dropped to the structure until the end of dropping of the release agent composition.

  As described above, in the rinsing process performed after the residue peeling process, rinsing with water is possible. A conventional amine-based release agent composition such as an ammonium fluoride-based release agent composition or hydroxylamine is a solvent-based release agent composition, and thus is not easily rinsed with water. In addition, these conventional stripping compositions may cause corrosion of metal wirings, particularly metal wirings containing Al, and the like due to mixing with water. Therefore, conventionally, rinsing has been performed using a solvent such as isopropanol. However, the release agent composition of the present embodiment is water-based, and further contains an organic phosphonic acid and a linear sugar alcohol having an anticorrosive action on metal wires, particularly metal wires containing Al. The above corrosion problems due to the mixing of the composition and water are small. Therefore, the residue peeling method of this embodiment or the method of manufacturing a semiconductor device of this embodiment can perform rinsing with water in the rinsing process, and is economical and has a very low environmental load.

  In addition, the semiconductor device manufactured by the method for manufacturing a semiconductor device according to the present embodiment adopting the residue peeling method according to the present embodiment has little residual residue, and metal wiring, particularly metal wiring including Al. Since the corrosion is extremely small, an increase in connection resistance due to residue residue and metal wiring corrosion is suppressed.

<Sample for evaluation>
An unwashed wafer having the following laminated structure and having a wiring containing Al having a wiring width of 0.25 μm (Al—Cu wiring) is divided into 1 cm squares to obtain evaluation samples.
(Laminated structure)
TiN / Al-Cu / TiN / SiO ₂ / semiconductor substrate

  A release agent composition having the composition shown in Table 1 was prepared and subjected to a peeling treatment by the following method, and the peelability to the residue and the corrosion resistance to the wiring containing Al were evaluated. In addition, the detail of the chemical product which used the release agent composition for preparation is as follows.

HEDP (1-hydroxyethylidene-1,1-diphosphonic acid) (manufactured by Solusia Japan, Diquest 2010R, 60% aqueous solution)
1,3-propanediamine (Merck Co., Ltd., for synthesis)
D-sorbitol (Wako Pure Chemical Industries, Ltd., grade 1)
D-mannitol (manufactured by Kanto Chemical Co., Ltd., special grade)
myo-Inositol (Wako Pure Chemical Industries, Ltd., special grade)
Ammonium silicofluoride (Morita Chemical Industry Co., Ltd., reagent grade)
Aminotri (methylenephosphonic acid) (manufactured by Solusia Japan, Dequest 2000, 50% aqueous solution)
Ammonia (manufactured by Toyama Pharmaceutical Co., Ltd., LSI Grade)
Pure water (electric conductivity at 25 ° C: 0.97 μS / cm)
The pH at 20 ° C. was measured using a pH meter (Toa Denpa Kogyo Co., Ltd., HM-30G).

(Peeling treatment)
One sample for evaluation was immersed in 30 ml of a 25 ° C. release agent composition for 1.5 minutes or 3 minutes. Thereafter, the sample was taken out from the release agent composition, and then immersed in 30 ml of ultrapure water at 25 ° C. for 1 minute. After this immersion in ultrapure water was repeated twice, nitrogen gas was sprayed onto the sample for evaluation and dried. Thus, the sample for evaluation which carried out the peeling process using the release agent composition was observed as follows.

(Evaluation of peelability and corrosion resistance)
Using a FE-SEM (scanning electron microscope), the sample before the peeling treatment and the sample after the peeling treatment are comparatively observed under a magnification of 50000 to 150,000 times, and the peelability to the residue according to the following evaluation criteria. And the anticorrosion property was evaluated. The results are shown in Table 1.

〔Evaluation criteria〕
(Removability to residue)
A: Residual residue is not confirmed at all.
○: The residue is removed by 50% or more.
Δ: Removal of residue is less than 50%.
X: A residue cannot be removed.
(Anti-corrosion)
(Double-circle): Corrosion is not seen at all on the exposed surface of the wiring containing Al.
○: The range of corrosion generated on the exposed surface of the wiring containing Al is a range of less than 50% of the area of the exposed surface.
(Triangle | delta): The range of the corrosion which arose on the exposed surface of the wiring containing Al is the range of 50% or more of the area of the said exposed surface.
X: Corrosion has occurred in the entire exposed surface of the wiring containing Al.

  If both peelability and anticorrosion were ◎ or ○, the product was accepted.

  As shown in Table 1, it contains an organic amine (1,3-propanediamine), an organic phosphonic acid (HEDP), a linear sugar alcohol (D-sorbitol or D-mannitol), and water, and has a pH of 9-13. When the stripping compositions of Examples 1 to 4 in the range of are used, both the stripping properties for Al and Ti-containing residues and the anticorrosion properties for Al-containing wiring are excellent even under low-temperature and short-time stripping conditions. I found out. It was also found that the peelability and anticorrosion properties were balanced for a relatively long time (for example, 3 minutes).

  The release agent composition of the present invention has a high corrosion inhibiting effect on metal wirings, particularly metal wirings containing Al, etc., has excellent peelability of residues in the vicinity of metal wirings containing Al under low-temperature and short-time peeling conditions, and the environment The load on is small. Therefore, the release agent composition of the present invention is suitable as a release agent composition used for manufacturing a semiconductor element having a metal wiring containing Al. For example, LCD (liquid crystal display), memory, CPU (central processing unit) It is suitable as a release agent composition used in the manufacturing process of electronic parts such as Furthermore, since the release agent composition of the present invention is suitable as a release agent composition used in a single wafer type release method, it can contribute to multi-product small-volume production.

Process sectional drawing explaining an example of the manufacturing method of the semiconductor element of this embodiment, or an example of the residue peeling method of this embodiment Process sectional drawing explaining an example of the manufacturing method of the semiconductor element of this embodiment, or an example of the residue peeling method of this embodiment Process sectional drawing explaining an example of the manufacturing method of the semiconductor element of this embodiment, or an example of the residue peeling method of this embodiment Process sectional drawing explaining an example of the manufacturing method of the semiconductor element of this embodiment, or an example of the residue peeling method of this embodiment Conceptual diagram explaining the single wafer peeling method using a spin coater Process sectional drawing explaining an example of the manufacturing method of the semiconductor element of this embodiment, or an example of the residue peeling method of this embodiment Process sectional drawing explaining an example of the manufacturing method of the semiconductor element of this embodiment, or an example of the residue peeling method of this embodiment Process sectional drawing explaining an example of the manufacturing method of the semiconductor element of this embodiment, or an example of the residue peeling method of this embodiment Process sectional drawing explaining an example of the manufacturing method of the semiconductor element of this embodiment, or an example of the residue peeling method of this embodiment

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Semiconductor substrate 2,15 Insulating layer 3,5 Barrier layer 4 Al layer 6a, 6b Resist pattern 7,13 Etching gas 8,14 Oxygen gas 4a Al wiring 9a, 16a Etching residue before ashing process 9b, 16b Residue 10 Silicon wafer 11 Spin coater 12 Stripper composition 17 Hole

Claims (11)

A release agent composition used in the process of manufacturing a semiconductor element including wiring,
An organic amine, an organic phosphonic acid, a linear sugar alcohol, and water,
Ri pH is from 9 to 13 der at 20 ° C.,
The release agent composition in which the weight ratio of the organic amine to the organic phosphonic acid (organic amine / organic phosphonic acid) in the release agent composition is 1/1 to 3.5 / 1. A release agent composition used in the process of manufacturing a semiconductor element including wiring,
Add organic amine, organic phosphonic acid, and linear sugar alcohol to water,
PH at 20 ° C. is 9-13 ,
A release agent composition obtained by adjusting the weight ratio of the organic amine and the organic phosphonic acid (organic amine / organic phosphonic acid) to 1/1 to 3.5 / 1 in the release agent composition. The weight ratio of the linear sugar alcohol to the total amount of the organic amine and the organic phosphonic acid [linear sugar alcohol / (organic amine + organic phosphonic acid)] is 1 / 0.03 to 1/36.
The release agent composition according to claim 1 or 2. The stripping composition according to claim 3, wherein the weight ratio [linear sugar alcohol / (organic amine + organic phosphonic acid)] is 1 / 0.3 to 1 / 0.8.   The stripping composition according to any one of claims 1 to 4, wherein the wiring contains aluminum. A method of manufacturing a semiconductor element including a semiconductor substrate and wiring,
Forming a metal layer and a resist pattern in this order on one main surface side of the semiconductor substrate, etching the metal layer using the resist pattern as a mask, and forming a wiring; and
An ashing step for ashing the resist pattern;
Removing a residue remaining in the vicinity of the wiring after the ashing step,
The said residue peeling process WHEREIN: The manufacturing method of the semiconductor element which removes the said residue using the peeling agent composition in any one of Claims 1-5.   The method of manufacturing a semiconductor element according to claim 6, wherein the wiring includes aluminum.   The method for manufacturing a semiconductor element according to claim 6, wherein a peeling treatment time in the residue peeling step is 3 minutes or less.   The method for manufacturing a semiconductor element according to claim 6 or 7, wherein, in the residue peeling step, the residue is removed by a single wafer peeling method.   The method of manufacturing a semiconductor element according to any one of claims 6 to 9, wherein the temperature of the release agent composition in the residue peeling step is 20 to 40 ° C.   The said wiring formation process WHEREIN: The barrier film containing TiN is formed in contact with the said metal layer in at least one before the formation of the said metal layer, and after the formation of the said metal layer. The manufacturing method of the semiconductor element as described in the term.

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