JPH0695396A - Developer composition and developing method - Google Patents

Abstract

PURPOSE:To provide the resist developer compsn. which does not corrode the oxidized films of a multilayered film substrate having the oxidized films and amphoteric metallic films and the developing method using such compsn. CONSTITUTION:A transparent electrode consisting of an ITO film 2 is formed on a glass substrate 1 and an aluminum film 6 is formed in a part of this transparent electrode. A positive resist coating film 7 is applied on this aluminum film 6 and after the film is dried, the film is exposed with UV rays and thereafter the unnecessary resist coating film 7 is removed by the developer contg. peroxide. Further, the aluminum film 6 is processed by etching and thereafter, the resist coating film 7 is removed by a peeling agent, by which the patterns are completed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developer composition useful for processing a multilayer film containing one or more oxide film and one or more amphoteric metal film using a resist, and a developing method using the same.
In particular, it relates to a developer composition capable of preventing hydrogen generation due to corrosion of an amphoteric metal and accompanying reduction corrosion of an oxide film.

[0002]

2. Description of the Related Art With the miniaturization and diversification of display elements such as EL, the materials used are not limited to metals, but various oxides,
Nitride and the like have come to be used, and their etching method is also disclosed in, for example, JP-A-58-120780.

Further, as a resist developing solution used prior to the above-mentioned etching, for example, as described in JP-A-63-261254, hydroxides, carbonates, and heavy salts of lithium, sodium, potassium, etc. Carbonates, phosphates, amines, quaternary ammonium hydroxides, etc.
Weakly alkaline aqueous solutions of various compounds are used.

[0004]

When the above-mentioned developing solution is used for photolithography of a multilayer film in which an amphoteric metal such as aluminum and an oxide film are mixed, the amphoteric metal is corroded by the alkali contained in the developing solution. Is generated and hydrogen is generated,
Since this hydrogen reduces and corrodes the oxide film, there are problems that the oxide film is discolored and dielectric breakdown occurs.

[0005]

In order to solve the above problems, the present invention provides a multilayer film containing at least one amphoteric metal such as aluminum and an oxide film such as metal oxide by etching such as photoetching. When processing,
As a developer for the resist used prior to this etching, a peroxide component is contained in addition to the alkali component.

According to the above method, it is possible to suppress the corrosion (hydrogen generation) of the amphoteric metal such as aluminum caused by the alkaline component contained in the developing solution, and as a result, the generated hydrogen reduces the oxide film. Since it does not corrode, problems such as dielectric breakdown of the oxide film do not occur.

The developer composition of the present invention is a conventionally known aqueous solution of an alkali component to which a peroxide component is added.
Examples of alkali components include hydroxides, carbonates, bicarbonates, phosphates, pyrophosphates, benzylamine, primary amines such as benzylamine, dimethylamine, dibenzyl of alkali metals such as lithium, sodium and potassium. Secondary amines such as amine and diethanolamine, tertiary amines such as trimethylamine, triethylamine and triethanolamine, morpholine, piperazine, piperidine,
Cyclic amines such as pyridine, polyamines such as ethylenediamine, hexamethylenediamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, trimethylbenzylammonium hydroxide,
Examples thereof include ammonium hydroxides such as trimethylphenylbenzylammonium hydroxide, sulfonium hydroxides such as trimethylsulfonium hydroxide, diethylmethylsulfonium hydroxide and dimethylbenzylsulfonium hydroxide, and other choline and silicate-containing buffer solutions.

The peroxide component can be appropriately selected in consideration of the alkaline component to be combined.
Particularly preferred is a perchloric acid such as sodium perchlorate and potassium perchlorate, a periodate such as sodium periodate and potassium periodate, and a peroxide selected from the group consisting of hydrogen peroxide. . The concentration of the peroxide component needs to be changed in consideration of the type and concentration of the alkaline component to be combined, the developing conditions such as spray development, immersion development, and puddle development. That is, if the amount is too small, the effect of suppressing hydrogen generation cannot be exhibited, and if the amount is too large, there is a possibility that harmful effects may occur. Therefore, the concentration of this peroxide component is preferably 0.01 to 10% by weight in terms of pure content, based on the total weight of the developer composition.
It is preferably from 1 to 1% by weight. When the peroxide component used is not stable with respect to the alkali component, these components may be stored separately and mixed immediately before use.

The oxide film formed on the substrate according to the present invention includes In ₂ O ₃ , SnO ₂ , ZnO, Ta ₂ O ₅ , and ITO.
A single or mixed system of metal oxides such as (indium-tin oxide) is used. As amphoteric metals, tin,
Lead, aluminum, antimony and the like are used, but aluminum is most preferably used.

The etchant for the above oxide film is hydrochloric acid-ferric chloride type, sulfuric acid-nitric acid type, etc., and the amphoteric metal etchant is phosphoric acid-nitric acid-acetic acid type, hydrofluoric acid-nitric acid type, potassium hydroxide. -Red blood salt type, borofluoric acid type for electrolytic etching, phosphoric acid-sulfuric acid-chromium oxide type, etc., but when using the developing solution of the present invention, phosphoric acid-nitric acid type is preferable, and phosphorus is particularly preferable. An acid: nitric acid weight ratio of 9: 1 is preferred. When the above phosphoric acid-nitric acid-acetic acid system is used, generation of hydrogen increases due to the influence of acetic acid, which may cause damage to the oxide film.

The photoresist which can be used in the developing solution of the present invention is not particularly limited, and can be arbitrarily selected from the commonly used positive type photoresist, acrylic polymerization negative type resist or its dry film.
A preferable positive photoresist is one composed of a composition containing a quinonediazide type photosensitive substance and a film forming substance. Examples of this quinonediazide-based photosensitive material include orthobenzoquinonediazide which is a quinonediazide group-containing compound, orthonaphthoquinonediazide, sulfonic acid of quinonediazides such as orthoanthraquinonediazide and a compound having a phenolic hydroxyl group or an amino group or a partial ester. Examples of the compound having a phenolic hydroxyl group or an amino group, for example, 2,3,4-trihydroxybenzophenone, 2,2 ', 4,4'-tetra Hydroxybenzophenone, polyhydroxybenzophenone such as 2,3,4,4'-tetrahydroxybenzophenone, or gallic acid, alkyl gallate, aryl gallate, esterified or etherified gallic acid with some hydroxyl groups left,
Phenol, p-methoxyphenol, dimethylphenol, hydroquinone, bisphenol A, naphthol, pyrocatechol, pyrogallol, pyrogallol monomethyl ether, pyrogallol-1,3-dimethyl ether, aniline, p-aminodiphenylamine and the like can be mentioned. And a particularly preferred quinonediazide group-containing compound is the above-mentioned polyhydroxybenzophenone and naphthoquinone-1,2-
Diazide-5-sulfonyl chloride or naphthoquinone-1,2-
It is a complete esterified product or a partial esterified product with diazido-4-sulfonyl chloride, and particularly, one having a degree of esterification of 70% or more is preferable.

Examples of the film-forming substance include novolac resins obtained by condensing aldehydes with phenol, cresol, xylenol and the like, acrylic resins, copolymers of styrene and acrylic acid, polymers of hydroxystyrene, polyvinyls. Alkali-soluble resins such as hydroxybenzoate and polyvinyl hydroxybenzal are effective. Of these, particularly preferred is cresol novolac resin.

A preferred acrylic polymerization negative resist is a photoresist as described in JP-A-63-261254, which has an ester of alkylenedicarboxylic acid and acrylic acid or methacrylic acid as an essential component. Acrylic linear copolymer, acrylic acid ester, methacrylic acid ester, acrylamide, methacrylamide, which forms a polymer by the action of a photopolymerization initiator,
It contains an ethylenically unsaturated compound such as an allyl compound, a vinyl ether compound and a vinyl ester compound, and a photopolymerization initiator such as an anthraquinone derivative, a benzoin derivative, benzophenone and phenanthrenequinone.

[0014]

[Function] In a multilayer film in which an oxide film and an amphoteric metal are mixed, hydrogen is generated due to the corrosion of the amphoteric metal due to the use of an alkaline developer and the reduction corrosion of the oxide film due to the action of the generated hydrogen is excessive in the developer. Prevent by adding an oxide.

[0015]

EXAMPLES Examples of the present invention will be described below. Example 1 FIGS. 1 to 6 are process diagrams showing the flow of photo-etching processing using the developing solution of the present invention. FIG. 1A shows the ITO film 2 formed on the glass substrate 1. The ITO film 2 is an oxide film suitable for producing a transparent electrode that is electrically and optically excellent, and is formed on the glass substrate 1 by a physical method such as electron beam evaporation, resistance heating evaporation, sputtering, or ion plating. It is formed by a chemical method such as a spray method or a CVD method. FIG. 2B shows a state in which the positive resist coating film 3 is formed on the ITO film 2. The positive resist coating film 3 is formed by using a coating device such as a roll coater, a curtain flow coater, a screen printing machine, a spray coater, and a spin coater, and then heated and dried to remove the solvent.

Next, as shown in FIG. 2A, the positive resist coating film 3 produced as described above is irradiated with actinic rays 5 such as ultraviolet rays through a pattern mask 4. As a light source of the actinic ray 5, a low pressure mercury lamp, a high pressure mercury lamp, an ultra high pressure mercury lamp,
Arc lamp, xenon lamp, excimer laser, X-ray,
An electron beam or the like can be used. As an exposure method, in addition to a method of bringing a mask pattern into close contact with a resist film, there is also a method of using a reduction projection exposure apparatus, a mirror type projection exposure apparatus, or the like. After completion of this exposure, unnecessary resist is removed with a developing solution to form a resist pattern as shown in FIG. Since the amphoteric metal film does not exist at this stage of this embodiment, a known developer is used.

Using the above-mentioned oxide film etchant, FIG.
As shown in (a), the unnecessary ITO film 2 is removed by using the resist pattern as a mask, and subsequently, the resist film 3 is also peeled and removed using an alkaline dilute aqueous solution as shown in (b).

A part of the transparent electrode made of the ITO film 2 formed as described above is covered with an aluminum film 6 which is an amphoteric metal as shown in FIG. 4 (a). The method of forming the aluminum film 6 is the same as the method of forming the ITO film 2.
From this point onward, a positive resist coating film 7 is formed (FIG. 4B) and dried in the same manner as described above, and an actinic ray 9 such as an ultraviolet ray is irradiated on the resist film 7 through a pattern mask 8 ( Figure 5 (a)). After this, unnecessary resist is removed with a developing solution as shown in FIG. 2B, but since the oxide film and the amphoteric metal film are both present here, it contains the peroxide component of the present invention. The developer composition is used to prevent the aluminum film 6 from being corroded to generate hydrogen. Then, after the unnecessary portion of the aluminum film 6 is selectively removed by using the above-mentioned amphoteric metal etchant using the resist pattern as a mask, the resist film 7 is also peeled and removed by using an alkaline dilute aqueous solution, as shown in FIG. Complete the pattern.

The above steps will be described more specifically with reference to examples. Example 1 First, an ITO film 2 having a film thickness of 1,000 liters was formed on a glass substrate 1 by a sputtering method (FIG. 1 (a)). A positive type resist coating film 3 (“OFPR-800” manufactured by Tokyo Ohka Kogyo Co., Ltd.) made of a quinonediazide compound and a phenol novolac type resin was applied onto the ITO film 2 and dried (FIG. 1 (b)). This positive resist coating film 3 was exposed through a pattern mask using a mirror type unit-magnification projection exposure apparatus (Fig. 2 (a)), and then a 2.38 wt% aqueous solution of tetramethylammonium hydroxide (developing solution "NMD-3 By using Tokyo Ohka Kogyo Co., Ltd., the unnecessary resist coating film 3 was removed at 23 ° C. to obtain the shape shown in FIG. 2 (b).

Next, the portion of the ITO film 2 exposed by removing the resist coating film 3 was treated with a hydrochloric acid-ferric chloride-based etchant solution (35% hydrochloric acid: water: ferric chloride = 1: 1: 0.5.
(Weight ratio) (FIG. 3 (a)), and the remaining resist coating film 3 was stripped with a 3% by weight aqueous solution of NaOH to obtain an ITO film pattern shown in FIG. 3 (b). An aluminum coating 6 having a thickness of 2 μm was formed on a part of the substrate by a sputtering method (FIG. 4 (a)), a positive resist coating film 7 was applied again, and dried (FIG. 4 (b)). The resist coating film 7 was exposed by the mirror type equal-magnification projection exposure apparatus described above (FIG. 5 (a)).

After the exposure, the resist coating film 7 was treated with 50 g of hydrogen peroxide having a concentration of 10% by weight with respect to 1,000 g of the above-mentioned "NMD-3" aqueous solution which is a developing solution according to the present invention (a pure amount based on the total weight). 0.48% by weight), using a developer prepared by adding
It was developed by immersion for 60 seconds (Fig. 5 (b)). At this time, no hydrogen is generated from the aluminum film 6, and therefore the ITO film 2
Corrosion due to the reduction of N did not occur. Thereafter, only the aluminum coating 6 was selectively etched with a phosphoric acid-sulfuric acid-based etchant, and the remaining resist coating film 7 was stripped with a stripping solution (diethylene glycol monobutyl ether: monoethanolamine = 7: 3 weight ratio, stripping solution 10). It was peeled off by using Tokyo Ohka Kogyo Co., Ltd. to obtain a good pattern shown in FIG.

Example 2 An ITO film having a film thickness of 1,000 liters and an aluminum film having a film thickness of 2 μm were formed in this order on a glass substrate by a sputtering method. Next, a positive type resist coating film (“OMER-6030” manufactured by Tokyo Ohka Kogyo Co., Ltd.) consisting of a quinonediazide compound and a phenol novolac type resin was applied onto this multilayer film and dried. After exposing this resist coating film, it is developed with a 1.0% by weight aqueous solution of potassium hydroxide at 25 ° C., and then the aluminum coating film is etched using an etchant of phosphoric acid: nitric acid = 9: 1. The ITO film was etched with an etchant. After removing the remaining resist film, a positive type resist coating film was applied again on this substrate, dried and partially exposed, and then 10 g of KClO4 per 1,000 g of potassium hydroxide 1.0 wt% aqueous solution (0.98 in pure content). (% By weight) was developed at 25 ° C. with the developer according to the invention. Furthermore, only the aluminum film portion of this substrate was etched with a phosphoric acid-nitric acid-based etchant.
There is no seepage of etchant from the side to the film,
A good substrate was obtained.

Example 3 After forming an ITO pattern in the same manner as in Example 1, an aluminum film is formed by a sputtering method, and the negative type is composed of an acrylic linear polymer, an ethylenically unsaturated compound and a photopolymerization initiator. A photoresist (“OP-2 RA” manufactured by Tokyo Ohka Kogyo Co., Ltd.) was applied with a spinner and dried. After exposing this substrate through a negative mask, apply sodium carbonate 1.2
2 g of NaClO4 per 1,000 g of a weight% aqueous solution (0.20 in pure content)
(% By weight) was developed with the developer according to the invention added. During this development, a good pattern was obtained without discoloration of the ITO film. After development, copper sulfate could be plated.

Example 4 A Ta film having a film thickness of 1,000 liters was formed on a glass substrate by a sputtering method, and then a positive resist (“OF” consisting of a quinonediazide compound and a phenol novolac resin was prepared according to a conventional method.
PR-5000 "manufactured by Tokyo Ohka Kogyo Co., Ltd.) was used for dry etching, and the Ta film pattern obtained was anodized to form Ta ₂ O ₅ on the Ta surface. An aluminum coating having a film thickness of 2 μm was formed on a part of this substrate by a sputtering method, a resist was applied again, dried, and then a pattern was exposed. 1,000 g of the developer "NMD-3"
Using a developer according to the present invention prepared by adding 50 g of 10 wt% hydrogen peroxide (0.48 wt% in terms of pure content) to
Immersion development was performed at 60 ° C. for 60 seconds. During this development, hydrogen is not generated,
Therefore, Ta ₂ O ₅ was not corroded by reduction. After that, the aluminum was etched with a phosphoric acid-sulfuric acid-based etchant, and the remaining resist was stripped with the above-mentioned "Stripping liquid 10" to obtain a good pattern.

Comparative Example 1 A pattern was formed in exactly the same manner as in Example 1 except that hydrogen peroxide was not added to the developing solution "NMD-3" during the second development (at the time of obtaining a resist pattern on an aluminum film). Was formed. At this time, generation of bubbles was observed on the aluminum film. After the unnecessary resist film was peeled off, the obtained substrate was observed. As a result, a part of the ITO film pattern, which should be originally transparent, was discolored to brown, and the product was rejected.

[0026]

As described above, when the developer composition of the present invention is used, the amphoteric metal layer is not corroded to generate hydrogen gas, so that the generated hydrogen gas may corrode the oxide film layer. Absent. Therefore, it is possible to obtain a substrate having a good pattern without defects such as dielectric breakdown and discoloration.

[Brief description of drawings]

FIG. 1 is a process drawing (first resist film formation) of forming a pattern on a substrate having an amphoteric metal film and an oxide film layer according to the present invention.

[FIG. 2] Same process drawing (first resist pattern formation)

[FIG. 3] Same process diagram (first etching)

FIG. 4 is a process drawing (second resist film formation)

FIG. 5 is the same process diagram (second resist pattern formation)

[FIG. 6] Same process drawing (second etching)

[Explanation of symbols]

1 ... Glass substrate, 2 ... ITO film, 3, 7 ... Resist coating film, 4, 8 ... Pattern mask, 5, 9 ... Actinic ray, 6 ... Aluminum coating film.

Claims (5)

[Claims] 1. A resist developer composition containing an alkali component, which is used for etching a multilayer film formed on a substrate, the multilayer film including at least one oxide film layer and at least one amphoteric metal film layer. A developer composition comprising an oxide component. 2. The developer composition according to claim 1, wherein the peroxide component is contained in an amount of 0.01 to 10% by weight in terms of pure content based on the total weight. 3. The developer composition according to claim 1, wherein the peroxide component is a peroxide selected from the group consisting of hydrogen peroxide, perchlorates and periodates. 4. The developer composition according to claim 1, wherein the amphoteric metal film layer is aluminum. 5. A step of forming a multilayer film having at least one oxide film layer and at least one amphoteric metal film layer on a substrate, a step of forming a resist film on the multilayer film, and then exposing the resist film. A developing method comprising: a step of developing a resist film after exposure using a developing solution containing a peroxide component together with an alkali component.