JP4850237B2 - Developer composition for photosensitive organic film - Google Patents

Description

  The present invention relates to a developer composition for a photosensitive organic film (photoresist or the like: hereinafter referred to as “photoresist” instead of “photosensitive organic film”). More specifically, the present invention relates to a developer composition for a photosensitive organic film, which is used for manufacturing a semiconductor integrated circuit, a semiconductor element circuit of a liquid crystal panel, and the like, which have excellent corrosion resistance against Al and good developability.

  A photosensitive organic film, for example, typically a photoresist and a developing solution composition, is used when developing a photoresist used for manufacturing a semiconductor integrated circuit, a semiconductor element circuit of a liquid crystal panel, and the like. For example, a semiconductor element circuit or an accompanying electrode part is manufactured as follows: First, a metal film such as Al is laminated on a substrate such as silicon or glass by a method such as CVD or sputtering; the metal film A photoresist is formed on the upper surface of the photoresist, and the photoresist is exposed to ultraviolet rays and exposed to light, and then developed using a photoresist developer composition to form a pattern; the patterned photoresist is masked The metal film is etched as follows: After the etching, the unnecessary photoresist is stripped and removed using a stripping composition. By repeating these operations, a semiconductor element circuit or the like is formed. Here, the metal film includes, for example, aluminum (Al); aluminum alloy such as aluminum-silicon-copper (Al-Si-Cu); titanium alloy such as titanium (Ti); titanium nitride (TiN); Silicon such as -Si and p-Si is used. These metal films are formed on the substrate as a single layer or a plurality of layers.

  Conventionally, as such a developer composition for a photoresist, an aqueous solution of an organic alkali or an inorganic alkali, in particular, an aqueous tetraalkylammonium hydroxide solution that is metal-free has been widely used.

  However, the photoresist developer composition is highly corrosive to Al. For this reason, the photoresist developer is not suitable for a substrate in which Al wiring or the like is already formed and the characteristics deteriorate when Al corrosion occurs. In particular, as described in Patent Documents 3 and 4, it is formed and used by exposure and development as an etch mask for a base film (here, a multilayer film such as Al, Al alloy, or Al / Mo / Al). The pattern of the photosensitive organic film (here, photoresist) is subjected to a second development process (hereinafter referred to as re-development) and deformed (in some cases, added to the re-development process and dissolved and reflow deformed) and used (again, the underlying film) In the case of etching, etc., it is difficult to use the photoresist developer. The reason is that during re-development processing, the underlying Al film or the like (Al or Al alloy single film, or multilayer film such as Al / Mo / Al) is formed on the wiring or the like by the first etching. The side of is also exposed. Moreover, compared to the first development processing, the area to be corroded is a very small one such as a wiring from a solid film state. For this reason, when developed (again), corrosion occurred intensively and at an accelerated rate, and the shape of the stepped surface such as the Al film changed greatly and was uncontrollable. Furthermore, there was a possibility of causing disconnection.

For this reason, various studies have been made in order to suppress Al corrosion of the photoresist. For example, Patent Document 1 describes a resist developer in which 20 to 50% by weight of a polyhydric alcohol is blended with a resist developer mainly composed of an organic base that does not contain metal ions. Patent Document 2 describes a resist developer composition that is an aqueous solution containing 1 to 10% by weight of an organic base, 1 to 10% by weight of a saccharide, and 1 to 10% by weight of a polyhydric alcohol. . However, even these resist developer compositions have insufficient Al anticorrosion properties.
Japanese Patent No. 3417432 JP 2003-330204 A JP 2005-159294 A JP 2005-159292 A

  Accordingly, an object of the present invention is to provide a photoresist developer having excellent corrosion resistance against Al and good developability.

  As a result of repeating various experiments to solve the above problems, the present inventors have found that a tetraalkylammonium hydroxide, a sugar alcohol having 5 or more carbon atoms, and a water-soluble organic solvent excluding a polyhydric alcohol in a specific range amount. In addition, when the ratio of the dissolution rate of the photoresist to the exposed part and the dissolution rate of the photoresist to the unexposed part of the photoresist is increased, Al corrosiveness is exhibited when used as a photoresist developer composition. The inventors have found that it is very small and has good developability, and have completed the present invention.

Therefore, the present invention provides A) 0.5 to 5% by weight of tetraalkylammonium hydroxide, B) 10 to 40% by weight of sugar alcohol having 5 or more carbon atoms, more preferably 12 to 30% by weight, C 3) 19 to 19% by weight, more preferably 11 to 17% by weight of water-soluble organic solvent excluding polyhydric alcohol and amine compound , and D) the remaining water, and dissolution in the exposed part of the photosensitive organic film The developer composition for a photosensitive organic film having a ratio of the speed to the dissolution rate of the photosensitive organic film with respect to the unexposed portion is 50 or more.

  In one aspect of the present invention, the content of the component B) is 80% or more of the content of the component C).

  In another aspect of the present invention, the component A) is at least one selected from tetramethylammonium hydroxide and tetraethylammonium hydroxide.

  In another embodiment of the present invention, the component B) is at least one selected from sorbitol and xylitol.

  In still another embodiment of the present invention, the component C) is at least one selected from sulfoxides, glycol ethers and amides. In yet another embodiment, the component C) is dimethyl sulfoxide. , Diethylene glycol monobutyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether, N, N-dimethylacetamide, and N-methyl-2-pyrrolidone.

The present invention can exhibit the following effects by the above-described configuration.
(1) In the composition of the present invention, the ratio of the dissolution rate of the photoresist to the exposed portion and the dissolution rate of the photoresist to the unexposed portion is 50 or more, the developability of the photoresist is good, and Al corrosiveness Is small, stable and easy to handle.
(2) The composition of the present invention does not prevent the development process from being controlled because the dissolution rate in the photoresist is too high, and the development process can be easily controlled, and the dissolution rate in the exposed photoresist is high. It can be processed quickly without being too small and requiring a long time for development.

  Examples of the component A) include tetramethylammonium hydroxide, tetraethylammonium hydroxide, choline, and dimethylbis (2-hydroxyethyl) ammonium hydroxide. In particular, tetramethylammonium hydroxide and tetraethylammonium hydroxide are suitable. These may be used alone or in combination of two or more.

  The content of component A) is 0.5 to 5% by weight. When the content of the component A) is less than 0.5% by weight, the development speed is too low, which is not suitable. Further, when the content of the component A) exceeds 5% by weight, a difference in dissolution rate between the exposed portion and the unexposed portion of the photoresist cannot be obtained, and a pattern cannot be formed, and Al corrosion cannot be suppressed. It is.

  Examples of the component B) include sugar alcohols having 5 or more carbon atoms (chain polyhydric alcohols in which sugar carbonyl groups are reduced, including oligosaccharide alcohols), such as sugar alcohols having 5 to 7 carbon atoms. If it is, it will not specifically limit, For example, arabinitol, sorbitol, xylitol, mannitol, ribitol, allitol, glucitol, iditol, galactitol, alititol, heptitol, maltitol, etc. are mentioned. Of these, sorbitol and xylitol are particularly preferable. These may be used alone or in combination of two or more.

  The content of the component B) is 10 to 40% by weight, preferably 12 to 30% by weight. If the content of the component B) is less than 10% by weight, the Al corrosivity increases, which is not suitable. On the other hand, when the content of the component B) exceeds 40% by weight, the development speed of the photoresist is too low, which is not suitable.

  Although it does not specifically limit as said C) component, A sulfoxide, glycol ethers, amides, etc. are mentioned preferably. Dimethyl glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether, etc. as amides, N, N-dimethyl as sulfoxides, dimethyl sulfoxide, diethyl sulfoxide, etc. Examples include formamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone and the like. Of these, dimethyl sulfoxide, diethylene glycol monobutyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether, N, N-dimethylacetamide, and N-methyl-2-pyrrolidone are particularly preferable. These may be used alone or in combination of two or more.

  The content of component C) is 3 to 19% by weight, but 11 to 17% by weight is preferred. When the content of the component C) is less than 3% by weight, the development speed of the photoresist is too low, which is not suitable. On the other hand, when the content of component C) exceeds 19% by weight, the ratio of the dissolution rate of the photoresist to the exposed portion and the dissolution rate of the unexposed portion is small, which is not suitable because a pattern cannot be formed.

  The component B) has the effect of suppressing Al corrosivity, but significantly reduces the solubility and developability of the photoresist. The component C) has the effect of improving the solubility of the photoresist and preventing the developability from being lowered by the component B). However, when the amount of the component C) that exceeds the content of the component B) is added, the solubility of the photoresist is excessively improved, and the difference in dissolution rate between the exposed and unexposed portions of the photoresist cannot be obtained. There is. Therefore, it is preferable that the content of the component B) is 80% or more of the content of the component C).

  In the composition of the present invention, the ratio of the dissolution rate of the photoresist to the exposed portion and the dissolution rate of the photoresist to the unexposed portion is 50 or more. When this ratio is less than 50, unexposed photoresist is also dissolved during development, resulting in poor developability. When the dissolution rate ratio is large (50 or more), the unexposed photoresist is hardly dissolved, and only the exposed photoresist is dissolved, so that developability is good. Preferably, it is 80 or more.

  Regardless of the dissolution rate ratio, the unexposed photoresist has a high dissolution rate, and when the unexposed photoresist is completely dissolved, the dissolution rate of the entire photoresist is too high and the development process cannot be controlled. Also, if the dissolution rate of the exposed photoresist is too small, it takes a long time for development, which is inappropriate. Accordingly, the dissolution rate of the unexposed photoresist is preferably 10 angstroms / second or less. The dissolution rate of the exposed photoresist is preferably 100 angstrom / second or more.

  To the composition of the present invention, additives that are used in a general photoresist developer composition such as a surfactant can be added to the extent that the object of the present invention is not impaired.

  The composition of the present invention can be prepared by blending the above components A) to C) and, if applicable, other additives and the remaining water. The solute concentration of the composition of the present invention can be adjusted as appropriate depending on the developing device to be used, but it can usually be a 36 to 85% by weight aqueous solution.

  The composition of the present invention is used as a developer for photoresist in the production of semiconductor integrated circuits, semiconductor device circuits of liquid crystal panels, and the like. The temperature, the development processing time, and the like at the time of use may be appropriately set and are not particularly limited, but are usually from room temperature to 50 ° C. and from about 20 seconds to several minutes. Further, the developing processing method is not particularly limited, and the processing can be performed using a commonly used developing device.

  The composition of the present invention has a low Al etching rate. That is, in the composition of the present invention, the Al etching rate can be 3 angstroms / second or less in the treatment at 50 ° C. Therefore, as described above, the photoresist developer composition of the present invention can develop an exposed photoresist on a semiconductor substrate or a liquid crystal glass substrate without causing Al corrosion. .

  The present invention will be described below based on examples, but it goes without saying that the present invention is not limited to these examples.

Example 1
(1) Al etching rate A Si wafer (that is, an Al single-layer blanket wafer) having a 10000 Å Al solid film formed on the surface thereof was immersed in a photoresist developer composition at 50 ° C. The substrate was taken out every 60 seconds, 120 seconds, and 180 seconds, washed with pure water, and then dried by blowing off pure water with an air gun using N 2 gas. Immediately after drying, the film thickness of Al was measured with a 4 Point Probe. The immersion time and the Al film thickness were plotted on a graph, and the Al etching rate was determined from the slope of the graph. The results are shown in Table 1. When the Al etching rate is low, the corrosiveness of Al is also small. Conversely, when the Al etching rate is large, the corrosiveness of Al is also large.

(2) Developability HMDS (hexamethyldisilazane) was spin-coated on a Si wafer and then baked at 100 ° C. for 2 minutes. Next, a positive photoresist NPR3510PG (manufactured by Nagase ChemteX Corporation) was spin-coated and prebaked at 100 ° C. for 2 minutes. Subsequently, the entire surface of the photoresist was exposed using PLA (manufactured by Canon) and completely exposed. Finally, post-baking was performed at 120 ° C. for 2 minutes to produce an exposed photoresist solid substrate (that is, a blanket wafer; the same applies hereinafter) having an average film thickness of 15000 angstroms. After HMDS was spin-coated on the Si wafer, it was baked at 100 ° C. for 2 minutes. Next, a positive photoresist NPR3510PG (manufactured by Nagase ChemteX Corporation) was spin-coated and prebaked at 100 ° C. for 2 minutes. Finally, post-baking was performed at 120 ° C. for 2 minutes to produce an unexposed photoresist solid substrate having an average film thickness of 15000 angstroms. After the substrates were prepared, the initial film thickness of the photoresist on both substrates was measured with an optical film thickness meter. Both substrates were immersed in a photoresist developer composition for 30 seconds at room temperature. After immersion, the substrate was taken out, washed with pure water, blown off pure water with an air gun using N2 gas, and naturally dried. After natural drying, the remaining resist film thickness was measured with a film thickness meter. The difference between the initial film thickness and the remaining film thickness was divided by the immersion time, and the resist dissolution rate (Å / s) was calculated. Further, the resist dissolution rate of the exposed photoresist solid substrate was divided by the resist dissolution rate of the unexposed photoresist solid substrate, and a resist dissolution rate ratio (hereinafter referred to as dissolution rate ratio) depending on the presence or absence of exposure was calculated. The results are shown in Table 1. Regardless of the dissolution rate ratio, if the dissolution rate of the unexposed photoresist is 500 Å / s or more, the dissolution rate of the entire photoresist is too high, and the development process cannot be controlled. Regardless of the dissolution rate ratio, if the dissolution rate of the exposed photoresist is less than 100 Å / s, development takes a long time, which is inappropriate. Of the comparative examples, in Comparative Examples 2, 3, 4, 6 and 12, the dissolution rate of the unexposed photoresist is 1 Å / s or less, or the dissolution rate of the exposed photoresist is 500 Å / s or more. Therefore, an accurate dissolution rate ratio cannot be calculated. Therefore, the dissolution rate ratio is not calculated.

The following abbreviations in Table 1 mean the compounds shown to the right of each abbreviation:
A1: Tetramethylammonium hydroxide B1: Sorbitol
B2: Xylitol C1: Dimethyl sulfoxide C2: N, N-dimethylacetamide C3: Diethylene glycol monoethyl ether C4: Diethylene glycol monomethyl ether D1: Pure water E1: Glycerin E2: Propylene glycol

Examples 2-6
Example 1 is the same as Example 1 except that the release agent composition shown in Table 1 was used.

Comparative Examples 1-12
Example 1 is the same as Example 1 except that the release agent composition shown in Table 1 was used.

  From Table 1, the developer composition for photoresists of the present invention (Examples 1 to 6) had a low Al etching rate and a sufficiently high dissolution rate ratio. Also, the exposed resist dissolution rate was sufficiently high, and the unexposed resist dissolution rate was sufficiently low.

  In contrast, the tetraalkylammonium hydroxide aqueous solution (Comparative Example 1) had a high Al etching rate although the dissolution rate ratio was sufficiently large. Further, an aqueous solution containing 2% by weight of tetraalkylammonium hydroxide and 15% by weight of a sugar alcohol having 5 or more carbon atoms and not containing a C component (Comparative Example 2) has a small Al etching rate, but is exposed to light. The rest was not dissolved. Further, it contains 2% by weight of tetraalkylammonium hydroxide, 15% by weight of water-soluble organic solvent, an aqueous solution containing no B component (Comparative Example 3), and 10% by weight of tetraalkylammonium hydroxide. An aqueous solution (Comparative Example 4) containing 15% by weight of a sugar alcohol having 5 or more carbon atoms and 15% by weight of a water-soluble organic solvent had a high Al etching rate and completely dissolved the unexposed photoresist. An aqueous solution (Comparative Example 5) containing 2% by weight of tetraalkylammonium hydroxide and 50% by weight of a sugar alcohol having 5 or more carbon atoms and containing 15% by weight of a water-soluble organic solvent was exposed. Almost no used photoresist could be dissolved. Further, an aqueous solution (Comparative Example 6) containing a large amount of 2% by weight of tetraalkylammonium hydroxide, 15% by weight of a sugar alcohol having 5 or more carbon atoms, and 50% by weight of a water-soluble organic solvent, and tetrahydroxide An aqueous solution (Comparative Example 12) containing 2.5% by weight of alkylammonium, excessively containing 7% by weight of a sugar alcohol having 5 or more carbon atoms, and 70% by weight of a water-soluble organic solvent was not used. The exposed photoresist was completely dissolved. Further, the composition described in Registration 3417432 (Comparative Examples 7 and 8) and the composition described in JP-A-2003-330204 (Comparative Examples 9 and 10) had a high Al etching rate. Further, an aqueous solution containing 0.5% by weight of tetraalkylammonium hydroxide, 1% by weight of sugar alcohol having 5 or more carbon atoms, and 40% by weight of a water-soluble organic solvent (comparative example) 11) has a small dissolution rate ratio and is unsuitable as a developer. Although the compositions of Comparative Examples 11 and 12 contained the components A to D, it was clear that they were resist stripper compositions and could not be used as developing compositions.

  Further, when the undercoat film is a multilayer film such as Al, Al alloy, or Al / Mo / Al using the developers of the compositions of Examples 1 to 6 described above, the above-mentioned Patent Documents 3 and 4 describe. It was used for the redevelopment processing of the photoresist pattern as described. Then, there is almost no corrosion of Al wiring or the like (Al or Al alloy single film, or multilayer film such as Al / Mo / Al) or change in the cross-sectional shape, and only the photoresist pattern is developed depending on the degree of photosensitivity. It was confirmed that it would be possible to draw out only the original purpose of progressing.

  The composition of the present invention has excellent Al anticorrosion properties, and also has excellent development performance. In the production of semiconductor integrated circuits, semiconductor element circuits of liquid crystal panels, etc., it is possible to produce highly reliable products with high yield. Therefore, it is suitable for manufacturing a semiconductor element circuit or the like. In particular, the second and subsequent development (re-development) processes performed after the first development process, that is, the second and subsequent development processes for the photosensitive organic film pattern that has been subjected to the first development process are performed. In the case where the composition is used, in the case where the photosensitive organic film pattern after being used as an etching mask is first used for the second and subsequent development treatments using the composition of the present invention, Alternatively, a second or subsequent development treatment is performed on the photosensitive organic film pattern after use for an etching mask of a single layer film of Al alloy or a multilayer film containing at least Al or Al alloy using the composition of the present invention. In the case of carrying out, particularly in these cases, it is effective when the photosensitive organic film is a photoresist.

Claims (11)

A) 0.5 to 5% by weight of tetraalkylammonium hydroxide, B) 10 to 40% by weight of sugar alcohol having 5 or more carbon atoms, and C) 3 to 3 of water-soluble organic solvent excluding polyhydric alcohol and amine compound. 19% by weight and D) for a photosensitive organic film containing the remaining water and having a ratio of the dissolution rate of the photosensitive organic film to the exposed part and the dissolution rate of the photosensitive organic film to the unexposed part of 50 or more Developer composition. The developer composition for a photosensitive organic film according to claim 1, wherein the content of the component B) is 80% or more of the content of the component C). The developer composition for a photosensitive organic film according to claim 1 or 2, wherein the content of the component B) is 12 to 30% by weight, and the content of the component C) is 11 to 17% by weight. The developer composition for a photosensitive organic film according to any one of claims 1 to 3, wherein the component A) is at least one selected from tetramethylammonium hydroxide and tetraethylammonium hydroxide. The developer composition for a photosensitive organic film according to any one of claims 1 to 4, wherein the component B) is at least one selected from sorbitol and xylitol. The developer composition for a photosensitive organic film according to any one of claims 1 to 5, wherein the component C) is at least one selected from sulfoxides, glycol ethers and amides. The component (C) is at least one selected from dimethyl sulfoxide, diethylene glycol monobutyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether, N, N-dimethylacetamide and N-methyl-2-pyrrolidone. The developing solution composition for photosensitive organic films in any one of -5. The developer composition for a photosensitive organic film according to any one of claims 1 to 7, which is used for the second and subsequent development processing for the photosensitive organic film pattern. The developer composition for a photosensitive organic film according to any one of claims 1 to 7, which is used for the second and subsequent development processes for the photosensitive organic film pattern after being used as an etching mask. 2. The first or subsequent development processing for a photosensitive organic film pattern after use for an etching mask of a single layer film of Al or Al alloy or a multilayer film containing at least Al or Al alloy. The developing solution composition for photosensitive organic films in any one of -7. The developer composition for a photosensitive organic film according to claim 1, wherein the photosensitive organic film is a photoresist.