KR20150080961A - Composition for forming metal oxides film pattern and a metal oxides film patternfabricated using the same - Google Patents

Abstract

The present invention relates to a solution type composition for forming a metal oxide thin film pattern and a metal oxide thin film pattern manufactured using the same and, more specifically, to a composition as a solution type composition for forming a metal oxide thin film pattern, comprising: an organic metal precursor; an acid-producing compound for producing acid by light irradiation; and a water-producing compound for releasing water by oxidation. According to the present invention, resolution and reliability of a metal oxide thin film pattern can be improved, and having effects in reducing costs with a simple manufacturing process.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a solution type composition for forming a metal oxide thin film pattern, and a metal oxide thin film pattern using the same. BACKGROUND OF THE INVENTION [0002]

The present invention relates to a solution type composition for forming a metal oxide thin film pattern and a metal oxide thin film pattern prepared using the same. More particularly, the present invention relates to a solution-type composition for forming a metal oxide thin film pattern comprising an acid-generating compound and a water-generating compound.

Recently, researches on oxide semiconductors to replace silicon-based semiconductor devices have been widely carried out. Oxide semiconductor thin films are used in various devices in the form of capacitor films, optical wave guides, and optical elements due to their electrical and optical properties. Oxide semiconductors have the same amorphous phase compared to hydrogenated amorphous silicon, but exhibit very good mobility and are therefore suitable for high-definition liquid crystal displays (LCDs) and active organic light emitting diodes (AMOLED). When using an oxide thin film for such a device, it is necessary to form a thin film pattern for circuit formation.

Conventionally, a metal oxide thin film is formed on a substrate by a CVD method, a stuttering method, or a sol-gel method, and then a metal oxide thin film pattern is formed through a normal resist patterning step. The conventional resist patterning process includes the steps of (a) applying a resist, (b) drying the resist by heating, (c) exposing the dried resist, (d) developing the exposed resist, e) etching the metal oxide formed on the exposed portion, and (f) removing the resist.

Conventional thin film patterning methods using a resist are complicated because i) the process is complicated, the cost is high, and ii) when the thin film is in the form of a composite metal oxide, specific elements are preferentially etched, iii) waste water such as strong acid used for metal oxide etching must be treated.

On the material side, studies on single, binary and ternary compounds based on indium oxide (In ₂ O ₃ ), zinc oxide (ZnO) and gallium oxide (Ga ₂ O ₃ ) And an oxide semiconductor manufacturing technology using a liquid-based process is advantageous in that it is less expensive than a high-cost vacuum deposition method.

1. Korean Patent Publication No. 10-2011-0055770 2. US registered patent US563744

The present invention also provides a solution-type composition for forming a metal oxide thin film pattern, which can be selectively removed through a heat treatment at a low temperature to form a pattern.

The present invention also provides a solution-type composition capable of forming a metal oxide thin film pattern excellent in resolution and reliability.

The present invention also provides a metal oxide thin film pattern produced by applying a printing process, not a deposition process, in order to reduce production costs.

The present invention also provides a metal oxide thin film pattern having excellent resolution and reliability.

One aspect of the present invention is a solution-type composition for forming a metal oxide thin film pattern, which comprises an organometallic precursor, an acid-generating compound which generates an acid by light irradiation, and a water- Lt; / RTI >

The acid-generating compound may be selected from the group consisting of N-Hydroxynaphthalimidetriflate, (2,6-Dinitrophenyl) methyl-4-methylbenzylsulfonate, (2-nitrophenyl) methyl 4-methylbenzenesulfonate, (2-nitrophenyl) methyltrifluoromethanesulfonate, (2-nitrophenyl) methyltrifluoromethanesulfonate), (3E) -3-hydrazinylidene-4-oxo-3,3,4-dihydro-naphthalen-1-sulfonic acid ((3E) -3- hydrazinylidene- dihydronaphthalene-1-sulfonic acid, 2- (3,5-dimethoxyphenyl) propan-2-yl N-cyclohexylcarbamate 2- (3,5- Bis (trichloromethyl) -1,3,5-triazine (2- (3,4-dimethoxystyryl) -4,6-bis (trichloromethyl) -1,3,5-triazine), 2,4-bis (trichloromethyl) -6- [2- (5-methylfuran- (2,4-bis (trichloromethyl) -6- [2- (5-methylfuran-2-yl) vinyl] -1,3,5-triazine).

Another aspect of the present invention may be a metal oxide semiconductor thin film pattern formed using the composition.

According to the present invention, the pattern can be formed by selectively removing the unexposed portion even if the heat treatment is performed at a low baking temperature.

In addition, the resolution and reliability of the metal oxide thin film pattern can be improved, and since the manufacturing process is simple due to the printing process without using the deposition equipment, the cost reduction effect is obtained.

In addition, a metal oxide thin film pattern having excellent reliability and resolution can be realized.

1 is a schematic view showing a process of forming an oxide thin film pattern using the composition according to the present invention.
FIG. 2 is a view showing an oxide thin film pattern formed using the composition according to the present invention and its resolution. FIG.
3 is a graph showing the electrical characteristics of an oxide thin film transistor fabricated using the composition according to the present invention.
FIG. 4 is a graph showing the electrical characteristics of an oxide thin film transistor fabricated using the composition according to Comparative Example 1. FIG.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. The embodiments of the present invention can be modified into various other forms, and the scope of the present invention is not limited to the embodiments described below.

FIG. 1 schematically shows a process for forming a metal oxide thin film pattern using the composition according to the present invention.

One aspect of the present invention is a solution-type composition for forming a metal oxide thin film pattern, which comprises an organometallic precursor, an acid-generating compound that generates an acid by light irradiation, and a water- Lt; / RTI >

The organometallic precursor reacts with water and undergoes hydrolysis and polymerization to convert to a gel state through the sol state. As the hydrolysis reaction progresses further, a polymerization reaction takes place, and the metal and oxygen are three-dimensionally bonded to cure the thin film.

The organometallic precursor is sensitive to light irradiation, and when exposed to light, polymerization occurs at the exposed portions, resulting in a thinner and more cured film. As a result, there is a difference in solubility between the exposed portion and the non-exposed portion, and a pattern can be formed using this phenomenon.

The organometallic precursor is not particularly limited as long as the metal hydroxide is formed through hydrolysis. Specifically, metal alkoxides, metal acetylacetonate complexes and metal carboxylates can be used. As the metal alkoxide, a low alkoxide such as ethoxide, propoxide, isopropoxide, butoxide or isobutoxide can be used. As the metal carboxylate, a metal compound of a low aliphatic acid such as acetate or propionate can be used. It is preferable to select the organic metal compound corresponding to the metal oxide thin film. Since the effect of water-forming compounds may vary depending on the organometallic precursors, this should be taken into account when selecting the organometallic precursors.

The organometallic precursor may comprise at least one selected from the group consisting of metal acetates, metal carboxylates and metal nitrates. The metal carboxylate may be acetate.

The metal may be aluminum, indium, gallium, zinc, tin, samarium, dysprosium, terbium, gadolinium, ytterbium, (ytterbium) and lutetium (lutetium) may be used.

The concentration of the organometallic precursor in the solution is preferably 1 to 20% by weight.

The acid-generating compound is selected from the group consisting of N-Hydroxynaphthalimidetriflate, (2,6-Dinitrophenyl) methyl-4-methylbenzenesulfonate, methylbenzenesulfonate, (2-nitrophenyl) methyl 4-methylbenzenesulfonate, (2-nitrophenyl) methyltrifluoromethanesulfonate, 3E) -3-hydrazinylidene-4-oxo-3,3,4-dihydronaphthalene-1-sulfonic acid ((3E) -3-hydrazinylidene-4-oxo-3,4-dihydronaphthalene- 2- (3,5-dimethoxyphenyl) propan-2-yl N-cyclohexylcarbamate), (2- (3,5-dimethoxyphenyl) propan- , 3,4-dimethoxystyryl-4,6-bis (trichloromethyl) -1, 4-dimethoxystyryl) -4,6-bis (trichloromethyl) 3,5-triazine), 2,4-bis (trichloromethyl) -6- [2- (5-methylfuran- trichloromethyl) -6- [2- (5 -methylfuran-2-yl) vinyl] -1,3,5-triazine. The content of the acid-generating compound may be 0.01 to 10 mol% have.

To further accelerate the hydrolysis reaction, an acid-generating compound may be used concurrently with the water-producing compound. The acid generated by the light irradiation acts as a catalyst for the curing reaction of the organic metal precursor to accelerate the curing, thereby making the solubility difference between the exposed portion and the non-exposed portion larger. It is also possible to reduce the light irradiation amount.

The composition may be prepared by previously introducing the water-generating compound together with the organometallic precursor. By doing so, water released from the water-generating compound by light irradiation can accelerate the curing reaction of the metal compound. That is, the water produced by the water-generating compound can act as a curing catalyst. In the exposed part exposed to light, the curing of the thin film proceeded to a considerable degree, and the difference in solubility between the exposed part and the non-exposed part was considerably increased as compared with the case where no water-generating compound was added. Since the water-generating compound is more sensitive to light than the hydrolyzable organometallic precursor itself, the curing reaction is initiated and promoted even though the light energy is smaller.

The water-generating compound is not particularly limited as long as it is capable of generating dehydration reaction in the molecule or intermolecularly by photoproduction to generate water. An aromatic organic compound having photosensitivity or having an electron withdrawing group such as a nitro group and an electron donating group such as a hydroxyl group in the molecule is useful. The electronic pull group and the electron pin group must be in close proximity. Examples of such compounds are O-nitrobenzyl alcohol, 1-hydroxymethyl-2-nitronaphthalene.

Examples of water-generating compounds include 2-nitrobenzyl alcohol, o-phthalic acid, 2-nitrobenzyl alcohol, 3-nitronaphthalene- 3-nitronaphthalene-2-methanol, 2,3-naphthalenedicarboxylic acid, (2E) -3- (2-hydroxyphenyl) -2-methylacrylic acid (2E) -3- (2-hydroxyphenyl) -2-methylacrylic acid, and (2,6-dinitrophenyl) methanol. . These water-generating compounds can produce water by dehydration.

The content of the water-generating compound may be from 0.01 to 50 mol% of the total composition. When the amount of the water-generating compound is less than the above range, the difference in solubility between the exposed portion and the non-exposed portion is not large, and the resolution of the pattern may be small. If the amount of the water-generating compound is more than the above range, the non-photocatalytic film is denatured by light irradiation, and a pattern with high resolution can not be formed.

One or more water-generating compounds and one or more acid-generating compounds may be used in combination.

Examples of the solvent include 2-methoxyethanol, 2-ethoxyethanol, 2-propoxyethanol, propylene glycol methyl ether, ethylene glycol ethylene glycol, dipropylene glycol methyl ether, and the like.

As a stabilizer, a chelate compound such as acetylacetone, ethanolamine, ethyloxo-butanoic acid, or the like may be further added to the solution. The stabilizer functions to prevent gelation of the solution during storage. The amount of the chelate compound may be 0.05 to 10 moles per mole of the organometallic precursor.

Another aspect of the present invention may be a thin film of nitrogen oxide formed using the composition.

Hereinafter, the process will be described.

First, the organometallic precursor may be added to an appropriate organic solvent and dissolved while stirring to prepare an organometallic precursor solution. In the case of preparing a composite oxide thin film pattern, two or more organic metal compounds may be added according to the ratio of each metal in the complex oxide.

Next, a solution composition can be prepared by adding a water-generating compound and an acid-generating compound. The water-generating compound and the acid-generating compound may be used in the form of a solution dissolved in a separate solvent.

Next, the solution composition may be coated on the substrate. There is no particular limitation on the method of applying the composition to the substrate as long as a thin film of uniform thickness can be formed. In general, a spin-coating method can be used. The thickness of the thin film may be increased by repeating the application process after the thin film is gelled. The thickness of the thin film is preferably 0.01 to 0.2 mu m.

Next, the thin film can be irradiated with light so as to form an image corresponding to a desired pattern. As the light source, other substances may be used depending on the photosensitizer (water-generating compound, acid-generating compound). Generally, ultraviolet rays, electron beams, ion beams, X-rays and the like can be used. The exposure can be performed by irradiating light through a photomask as in the conventional method. The light energy is preferably at least 100 mJ / cm 2, but is not limited thereto, and may vary depending on the thickness of the thin film and the type of the photosensitizer.

In the exposed part, curing reaction, hydrolysis reaction, polymerization reaction proceeds and the coated thin film becomes denser and hardened, and the solubility in solvents such as alcohol decreases. When a water-generating compound is present, a curing reaction of the exposed portion can be promoted with a small amount of light energy, and even if ultraviolet rays having a low energy density are used, curing can be sufficiently achieved.

Next, after the exposure, the thin film can be maintained in a dry inert gas atmosphere at 40 to 100 DEG C for 1 to 10 minutes. Thus, the curing reaction of the thin film of the exposed part is selectively promoted by blocking moisture in the air, and the difference in solubility between the exposed part and the non-exposed part can be increased.

Next, the thin film can be dried by removing moisture and organic solvent remaining in the pattern (exposed portion) by heating the substrate. For example, at 100 to 150 ° C for 5 to 10 minutes.

Next, the non-exposed portion of the thin film that has not been cured can be removed through development using a solvent. The development is performed so that the unexposed portion is completely removed and the exposed portion is not essentially removed. The development conditions may vary depending on the light irradiation amount, the heat treatment, and the type of the developing solvent. For example, the thin film may be immersed in a solvent for 10 seconds to 10 minutes. As a result, a negative-type pattern composed of an exposed portion can be formed on the substrate. Any solvent may be used as long as the developer has a high solubility in the uncured unexposed area but a small solubility in the cured exposed area. Specifically, it is preferable to use water or an alcohol. As the alcohol, alkoxy alcohols such as 2-methoxyethanol and 2-ethoxyethanol are preferable. When the solubility of the alcohol is high and the exposed portion is dissolved, the solubility can be controlled by adding an alkyl alcohol such as ethyl alcohol or isopropyl alcohol. It is not necessary to use a strong acid such as hydrofluoric acid / hydrochloric acid mixed acid in the development, and a safe and inexpensive solvent can be used.

Next, it can be washed using an organic solvent. This is to prevent the thin film from dissolving more than necessary. As the washing solution, it is preferable to use an organic solvent having little or no solubility in the exposed portion. For example, esters (ethyl acetate), ketones (methyl ethyl ketone, methyl isobutyl ketone), hydrocarbons (toluene, n-hexane) An alcohol such as isopropyl alcohol having a relatively low polarity may be used as a washing solution.

Next, the desired metal oxide thin film pattern can be formed by completely converting the metal compound into the metal oxide by heat treatment of the substrate. The heat treatment can be performed at 200 to 500 ° C for 10 minutes to 2 hours in an open air atmosphere.

The invention IZO, IZTO, IGZO, ZTO, ITO, HfIZO, IGO, PZT, PLZT, STO, BTO, BSTO, Bi 4 Ti 3 O 12, Ta 2 O 5, TiO 2, PbO, ZrO 2, Al 2 O ₃ , SnO ₂ , RuO _2, and the like. Further, the present invention is not limited to the oxide semiconductor thin film, but can be applied to other insulating materials.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples.

Example

361 mg of indium (III) acetate, 152 mg of zinc acetate, 306 mg of 2-nitrobenzyl alcohol, and 2-methoxy-n-hydroxynaphthalimidetriflate Was dissolved in 10 mL of 2-methoxyethanol to prepare a metal oxide precursor solution (12.5 mL). 2.5 mL of acetylacetone was added thereto as a stabilizer, and the mixture was stirred at 700 rpm for 12 hours.

1 ml of the solution composition was spin-coated at 3000 rpm for 30 seconds on an n ++ doped Si wafer subjected to UV ozone cleaning with yellow light. The wafer was loaded in a 254 nm UV exposure machine and irradiated with UV at 500 mJ / cm < ² > for 3 minutes using a photomask under nitrogen purge. As above, the UV lamp was changed to a 365 nm UV lamp and irradiated with UV of 500 mJ / cm ^{2 by} the same exposure apparatus for 5 minutes. The photomask used was a photomask in which the width of each line was 10 mu m and the interval between the lines was 10 mu m. The wafer was loaded and baked on a hot plate at 60 占 폚 for 1 minute. The wafer was immersed in a bath containing 2-propanol to remove unexposed portions to form a pattern. Washed with distilled water, and then heat-treated at 400 ° C for 1 hour in an air atmosphere to prepare an oxide thin film pattern.

Comparative Example

The composition was prepared in the same manner as in Example except that N-hydroxynaphthalimidetriflate was not used.

evaluation

Reliability

The line width of the metal oxide thin film pattern was measured using a microscope. Ten points were measured. The deviation was judged to be "good" when the deviation of the measured value was within 5% and "bad" when the deviation was 5% or more. In the case of the embodiment, the deviation is about 3%, and it is judged to be good. However, in the case of the comparative example, the pattern could not be formed at all.

resolution

The resolution of the thin film was measured using an independent patterned photomask of 300 microns, 100 microns, and 50 microns spaced at the same intervals, and the state of the pattern was observed with an optical microscope. Based on the minimum interval. A photograph of the thin film pattern according to the embodiment is shown in Fig. As shown in FIG. 2, in the case of the embodiment, the thin film pattern was clearly formed, and the resolution was 50 μm. However, in the case of the comparative example, since the pattern itself was not formed, the corresponding degree could not be measured.

Electrical characteristic

After probes were probed on the gate and source / drain electrodes of the thin film transistor fabricated according to Examples and Comparative Examples of the present invention, the gate voltage was changed from -20 V to 40 V while the drain voltage was fixed at 40 V The transfer (I _d -V _g ) curves obtained in the Examples and Comparative Examples are shown in FIG. 3 (Example) and FIG. 4 (Comparative Example). The IV characteristics of the TFT were measured using a semiconductor parameter analyzer (Agilent B1500A).

The mobility, threshold voltage, and current on-off ratio in the saturation region from the transfer (I _d -V _g ) curve are analyzed and shown in Table 1.

Mobility
(cm ² / Vs) electric current
On-off ratio Threshold voltage
(V) Example 9.46 1.97E + 06 3.40 Comparative Example 0.51 1.78E + 06 5.08

Referring to Table 1, FIG. 3 and FIG. 4, the threshold voltage is lower than that of Comparative Example 1 in which the oxide-thin film is patterned by dividing the passive elements into the oxide- The sol-gel reaction was promoted by the water-forming reaction, and the mobility was remarkably improved.

The terms used in the present invention are intended to illustrate specific embodiments and are not intended to limit the invention. The singular presentation should be understood to include plural meanings, unless the context clearly indicates otherwise. The word "comprises" or "having" means that there is a feature, a number, a step, an operation, an element, or a combination thereof described in the specification. The present invention is not limited by the above-described embodiments and the accompanying drawings, but is intended to be limited only by the appended claims. It will be apparent to those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. something to do.

Claims (8)

As a solution type composition for forming a metal oxide thin film pattern,
Organometallic precursors;
An acid-generating compound which generates an acid by light irradiation; And
A water-generating compound that is oxidized to release water.
The method according to claim 1,
Wherein the content of the acid-generating compound is 0.01 to 10 mol% of the total composition and the content of the water-generating compound is 0.01 to 50 mol% of the total composition.
The method according to claim 1,
The acid-generating compound may be selected from the group consisting of N-hydroxynaphthalimidetriflate, (2,6-dinitrophenyl) methyl-4-methylbenzenesulfonate 2-nitrophenyl methyl 4-methylbenzenesulfonate, (2-nitrophenyl) methyltrifluoromethanesulfonate), (2-nitrophenyl) methyl 4-methylbenzenesulfonate, (3E) -3-hydrazinylidene-4-oxo-3,3,4-dihydronaphthalene-1-sulfonic acid ((3E) -3-hydrazinylidene- sulfonic acid, 2- (3,5-dimethoxyphenyl) propan-2-yl N-cyclohexylcarbamate, 2- ( (3,4-dimethoxystyryl) -4,6-bis (trichloromethyl) -1, 3,4-dimethoxystyryl) -4,6-bis (trichloromethyl) , 3,5-triazine), 2,4-bis (trichloromethyl) -6- [2- (5-methylfuran- bis (trichloromethyl) - 6- [2- (5-methylfuran-2-yl) vinyl] -1,3,5-triazine).
The method according to claim 1,
The water-producing compound may be selected from the group consisting of 2-nitrobenzyl alcohol, o-phthalic acid, 3-nitronaphthalene-2-methanol, (2E) -3- (2-hydroxyphenyl) -2,3-naphthalenedicarboxylic acid, 3-naphthalenedicarboxylic acid, 2-methylacrylic acid, (2,6-dinitrophenyl) methanol, and the like.
The method according to claim 1,
Wherein the organometallic precursor comprises at least one selected from the group consisting of metal acetates, metal carboxylates, and metal nitrates.
6. The method of claim 5,
The metal may be aluminum, indium, gallium, zinc, tin, samarium, dysprosium, terbium, gadolinium, ytterbium, (ytterbium) and lutetium (lutetium).
The method according to claim 1,
Examples of the solvent include 2-methoxyethanol, 2-ethoxyethanol, 2-propoxyethanol, propylene glycol methyl ether, ethylene (ethylene glycol) glycol, and dipropylene glycol methyl ether. < Desc / Clms Page number 13 >
A metal oxide thin film pattern produced using the composition of any one of claims 1 to 7.

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