KR20230020810A - Composition for forming silica layer, silica layer, and electronic device - Google Patents

Abstract

A composition for forming a silica layer including a silicon-containing polymer and a solvent and having a viscosity difference of 400 cps to 2,200 cps between 70% concentrated solids and 50% concentrated solids, a silica layer manufactured therefrom, and an electronic device including the silica film.

Description

Composition for forming silica film, silica film, and electronic device

The present disclosure relates to a composition for forming a silica film, a silica film, and an electronic device manufactured thereby.

A flat panel display device uses a thin film transistor (TFT) including a gate electrode, a source electrode, a drain electrode, and a semiconductor as a switching element, and a gate line for transmitting a scan signal to control the thin film transistor. ) and a data line for transmitting a signal to be applied to the pixel electrode are provided in the flat panel display device. In addition, an insulating film is formed between the semiconductor and various electrodes to separate them. The insulating layer may be a silica layer containing a silicon component.

In order to form a silica film having such insulating properties, a coating solution containing inorganic polysilazane was used as a spin-on dielectric (SOD). At this time, since the thickness of the silica film (Thickness: THK) varies depending on the position of the substrate, it may affect the progress of the subsequent process, which may adversely affect the insulation characteristics of the product.

In particular, when a coating solution containing inorganic polysilazane is applied on a pattern wafer through a spin coating method and cured, the thickness of the silica film (THK) varies depending on the location of the wafer and the location of the pattern block. this happens If the thickness (THK) of the film is not uniform, it may adversely affect subsequent processes such as CMP (Chemical Mechanical Polishing).

Therefore, in the existing inventions, attempts have been made to solve the above problem by increasing the molecular weight during polysilazane synthesis, but when the molecular weight of polysilazane increases, problems such as gelation upon contact with moisture may occur. there is.

One embodiment provides a composition for forming a silica film capable of forming a film having a uniform thickness.

Another embodiment provides a silica film prepared from the composition for forming a silica film.

Another embodiment of the present invention provides an electronic device including the silica film.

According to one embodiment, a composition for forming a silica film comprising a silicon-containing polymer and a solvent and having a difference in viscosity between 70% and 50% concentrated solids of 400 cps to 2,200 cps is provided.

The viscosity of the 70% concentrated solids may be 450 cps to 2,300 cps.

The viscosity of the 50% concentrated solids may be 20 cps to 100 cps.

The silicon-containing polymer may be polysilazane, polysiloxazane, or a combination thereof.

The polysilazane may be inorganic polysilazane.

The silicon-containing polymer may have a weight average molecular weight of 4,000 g/mol to 20,000 g/mol.

The silicon-containing polymer may be included in an amount of 0.1 to 30% by weight based on the total amount of the composition for forming a silica film.

According to another embodiment, a silica film prepared from the above-described composition for forming a silica film is provided.

According to another embodiment, an electronic device including the silica film described above is provided.

By controlling the viscosity of the concentrated solid content of the composition, it is possible to improve the thickness distribution of the silica film thickness and implement a silica film with a uniform thickness.

1 is a schematic diagram showing a location for measuring the thickness of a pattern wafer for evaluating thickness uniformity.

Embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the present invention. However, the present invention may be embodied in many different forms and is not limited to the embodiments set forth herein.

In the drawings, the thickness is shown enlarged to clearly express the various layers and regions. Like reference numerals have been assigned to like parts throughout the specification. When a part such as a layer, film, region, plate, etc. is said to be "on" another part, this includes not only the case where it is "directly on" the other part, but also the case where there is another part in between. Conversely, when a part is said to be "directly on" another part, it means that there is no other part in between.

Unless otherwise defined herein, 'substituted' means that a hydrogen atom in a compound is a halogen atom (F, Br, Cl, or I), a hydroxyl group, an alkoxyl group, a nitro group, a cyano group, an amino group, an azido group, or an amino group. Dino group, hydrazino group, hydrazono group, carbonyl group, carbamyl group, thiol group, ester group, carboxyl group or its salt thereof, sulfonic acid group or its salt thereof, phosphoric acid group or its salt thereof, C1 to C20 alkyl group, C2 to C20 alkenyl group, C2 to C20 alkynyl group, C6 to C30 aryl group, C7 to C30 arylalkyl group, C1 to C30 alkoxy group, C1 to C20 heteroalkyl group, C2 to C20 heteroaryl group, C3 to C20 heteroarylalkyl group, C3 to C30 cycloalkyl group, C3 to C15 cycloalkenyl group, C6 to C15 cycloalkynyl group, C2 to C30 heterocycloalkyl group, and a substituent selected from combinations thereof.

In addition, unless otherwise defined herein, 'hetero' means containing 1 to 3 heteroatoms selected from N, O, S and P.

In addition, in this specification, "*" means a part connected to the same or different atom or chemical formula.

Hereinafter, a composition for forming a silica film according to an embodiment of the present invention will be described.

A composition for forming a silica film according to an embodiment includes a silicon-containing polymer and a solvent, and the difference between the viscosity of 70% concentrated solids and the viscosity of 50% concentrated solids is 400 cps to 2,200 cps, for example, 500 cps to 2,100 cps, For example, it may be 800 cps to 2,000 cps.

When the difference between the viscosity of the 70% concentrated solid content and the 50% concentrated solid content of the composition for forming a silica film satisfies the above range, thickness distribution may be improved, and accordingly, a silica film having a uniform thickness may be implemented.

When the difference between the viscosity of the 70% concentrated solids and the 50% concentrated solids of the composition for forming a silica film satisfies the above range, the thickness standard deviation may be 10 nm or less, for example, 1 nm to 10 nm, for example 3 nm to 8 nm.

In the present invention, the viscosity of each composition for forming a silica film was measured under the measurement conditions described below using a viscometer of model name LVDV3 manufactured by Brookfield.

The silicon-containing polymer contained in the composition for forming a silica film may be, for example, polysilazane (organic-inorganic polysilazane), polysiloxazane (organic-inorganic polysiloxazane), or a combination thereof.

The silicon-containing polymer may include, for example, a moiety represented by Chemical Formula 1 below.

[Formula 1]

In Formula 1, R ₁ to R ₃ are each independently hydrogen, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C3 to C30 cycloalkyl group, a substituted or unsubstituted C6 to C30 aryl group, or a substituted Or an unsubstituted C7 to C30 arylalkyl group, a substituted or unsubstituted C1 to C30 heteroalkyl group, a substituted or unsubstituted C2 to C30 heterocycloalkyl group, a substituted or unsubstituted C2 to C30 alkenyl group, a substituted or unsubstituted C1 to C30 alkoxy group, carboxyl group, aldehyde group, hydroxy group, or a combination thereof,

The "*" means a connection point.

For example, the silicon-containing polymer may be polysilazane produced by reacting halosilane with ammonia.

For example, the polysilazane may be inorganic polysilazane.

For example, the silicon-containing polymer included in the composition for forming a silica film may include a moiety represented by Chemical Formula 2 below.

[Formula 2]

R ₄ to R ₇ in Formula 2 are each independently hydrogen, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C3 to C30 cycloalkyl group, a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C6 to C30 aryl group, Unsubstituted C7 to C30 arylalkyl group, substituted or unsubstituted C1 to C30 heteroalkyl group, substituted or unsubstituted C2 to C30 heterocycloalkyl group, substituted or unsubstituted C2 to C30 alkenyl group, substituted or unsubstituted C1 to C30 heterocycloalkyl group A C30 alkoxy group, a carboxyl group, an aldehyde group, a hydroxy group, or a combination thereof;

The "*" means a connection point.

For example, the silicon-containing polymer may include a portion represented by Chemical Formula 1 and/or a portion represented by Chemical Formula 2, and may further include a portion represented by Chemical Formula 3 below.

[Formula 3]

The portion represented by Formula 3 has a structure in which terminal portions are capped with hydrogen, which may be included in an amount of 15 to 35% by weight based on the total content of Si-H bonds in the polysilazane or polysiloxazane structure. When the portion of Chemical Formula 3 is included in the above range in the polysilazane or polysiloxazane structure, oxidation reaction occurs sufficiently during heat treatment, while preventing the SiH ₃ portion from being scattered as SiH ₄ during heat treatment to prevent shrinkage, thereby preventing cracks can be prevented from occurring.

The weight average molecular weight of the silicon-containing polymer is between 4,000 g/mol and 20,000 g/mol, such as between 5,000 g/mol and 20,000 g/mol, such as between 6,000 g/mol and 20,000 g/mol, such as 7,000 g /mol to 15,000 g/mol, for example, 7,000 g/mol to 10,000 g/mol, but is not limited thereto. When the weight average molecular weight of the silicon-containing polymer satisfies the above range, a silica film prepared from the composition for forming a silica film may have excellent film thickness uniformity characteristics.

For example, the silicon-containing polymer may be included in an amount of 0.1% to 30% by weight based on the composition for forming a silica film.

The solvent included in the composition for forming a silica film is not particularly limited as long as it can dissolve the silicon-containing polymer, and specifically, benzene, toluene, xylene, ethylbenzene, diethylbenzene, trimethylbenzene, triethylbenzene, Cyclohexane, cyclohexene, decahydronaphthalene, dipentene, pentane, hexane, heptane, octane, nonane, decane, ethylcyclohexane, methylcyclohexane, cyclohexane, cyclohexene, p-mentane, dipropylether, dibutyl It may include at least one selected from the group consisting of ether, anisole, butyl acetate, amyl acetate, methyl isobutyl ketone, and combinations thereof.

The composition for forming the silica film may further include a thermal acid generator (TAG).

The thermal acid generator is an additive for improving the developability of the composition for forming a silica film, and allows the organosilane-based condensate included in the composition to be developed at a relatively low temperature.

The thermal acid generator is not particularly limited as long as it is a compound capable of generating an acid (H ⁺ ) by heat, but a compound that is activated at 90° C. or higher to generate sufficient acid and has low volatility may be selected.

The thermal acid generator may be selected from, for example, nitrobenzyl tosylate, nitrobenzylbenzenesulfonate, phenol sulfonate, and combinations thereof.

The thermal acid generator may be included in an amount of 0.01 to 25% by weight based on the total content of the composition for forming a silica film, and when included in the above range, the condensate polymer may be developed at a relatively low temperature and coating properties may be improved. there is.

The composition for forming the silica film may further include a surfactant.

The surfactant is not particularly limited, and examples thereof include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, and polyoxyethylene oleyl ether, and polyoxyethylene nonylphenol ether. polyoxyethylene alkyl allyl ethers, polyoxyethylene polyoxypropylene block copolymers, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, polyoxyethylene sorbitate, etc. Nonionic surfactants such as polyoxyethylene sorbitan fatty acid esters such as tan monostearate, polyoxyethylene sorbitan trioleate, and polyoxyethylene sorbitan tristearate, Etop EF301, EF303, EF352 (Tochem Products), Megapack F171, F173 (manufactured by Dainippon Ink Co., Ltd.), Prorad FC430, FC431 (manufactured by Sumitomo 3M Co., Ltd.), Asahi Guard AG710, Saffron S-382, SC101, SC102, SC103, SC104, fluorine-based surfactants such as SC105 and SC106 (manufactured by Asahi Glass Co., Ltd.), organosiloxane polymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.), and other silicone-based surfactants.

The surfactant may be included in an amount of 0.001 to 10% by weight based on the total amount of the composition for forming a silica film, and when included in the above range, the dispersibility of the solution may be improved and the uniformity of the film thickness may be increased during film formation.

The composition for forming the silica film may be in the form of a solution in which the silicon-containing polymer and the components are dissolved in a mixed solvent.

According to another embodiment, the steps of applying the above-described composition for forming a silica film, drying the substrate coated with the composition for forming a silica film, and curing the composition for forming a silica film may be included. .

The composition for forming a silica film may be applied by a solution process, such as spin-on coating, slit coating, or inkjet printing.

The substrate may be, for example, a device substrate such as a semiconductor or liquid crystal, but is not limited thereto.

When the application of the composition for forming the silica film is completed, the substrate is then dried and cured. The drying and curing may be performed at a temperature of, for example, about 100° C. or higher, and may be performed by applying energy such as heat, ultraviolet rays, microwaves, sound waves, or ultrasonic waves.

For example, the drying may be performed at about 100° C. to about 200° C., and the solvent in the composition for forming a silica layer may be removed through the drying step. In addition, the curing may be performed at about 250° C. to 1,000° C., and the composition for forming a silica film may be converted into an oxide film by passing through the corresponding curing step.

According to another embodiment of the present invention, a silica membrane prepared according to the above method is provided. The silica film may be, for example, an insulating film, a separator film, or a hard coating film, but is not limited thereto.

According to another embodiment of the present invention, an electronic device including a silica film prepared according to the above method is provided. The electronic device may be, for example, a display device such as an LCD or LED, or a semiconductor device.

Hereinafter, embodiments of the present invention described above will be described in more detail through examples. However, the following examples are for illustrative purposes only and do not limit the scope of the present invention.

Preparation of a composition for forming a silica film

Synthesis Example 1: Preparation of semi-product (A) of inorganic polysilazane

로 냉각한다. 이어서 디클로로실란 100ｇ을 １시간에 걸쳐서 서서히 투입한다. 이어서 반응기에 암모니아 70ｇ을 ３시간에 걸쳐서 서서히 투입한다. 암모니아 투입 완료 후 건조 질소를 30분간 투입하고, 반응기 내에 잔존하는 암모니아를 제거한다. 얻어진 백색의 슬러리상의 생성물을 건조 질소 분위기 중에서 １㎛의 테프론제 여과기를 사용하여 여과하여 여과액 1,000g을 얻는다. 여기에 건조 자일렌 1,000g을 첨가한 후, 회전 증발 농축기를 사용하여 용매를 피리딘에서 자일렌으로 치환하는 조작을 총３회 반복하면서 고형분을 60%로 조절하고, 포어 사이즈 0.1㎛의 테프론제 여과기로 여과한다. 상기 과정을 거쳐 고형분 60%의 중량 평균 분자량 3,000 g/mol인 무기폴리실라잔 반제품(A)을 얻는다.The interior of a reactor with a 2L capacity stirrer and a temperature controller is purged with dry nitrogen. Then, 1,500 g of dry pyridine was put into the reactor and this was

cool down with Subsequently, 100 g of dichlorosilane was gradually introduced over 1 hour. Subsequently, 70 g of ammonia was gradually introduced into the reactor over 3 hours. After completion of the ammonia input, dry nitrogen is added for 30 minutes, and the ammonia remaining in the reactor is removed. The obtained product in the form of a white slurry was filtered in a dry nitrogen atmosphere using a 1 μm Teflon filter to obtain 1,000 g of a filtrate. After adding 1,000 g of dry xylene to this, the operation of substituting the solvent from pyridine to xylene using a rotary evaporator was repeated three times in total to adjust the solid content to 60%, and a Teflon filter with a pore size of 0.1 μm filter with Through the above process, an inorganic polysilazane semi-finished product (A) having a solid content of 60% and a weight average molecular weight of 3,000 g/mol is obtained.

(Manufacture of inorganic polysilazane)

Example 1

100 g of the inorganic polysilazane semi-product (A) prepared in Synthesis Example 1, 350 g of dry pyridine, and 100 g of dry xylene were put into a reactor with a capacity of 1 L and equipped with a stirrer and a temperature controller, and heated to 100 ° C. The operation of replacing the solvent with dibutyl ether using a rotary evaporator was repeated four times at 70° C. while the solid concentration was adjusted to 50% and 70%, respectively, and then filtered through a 0.1 μm Teflon filter to finally A composition for forming a silica film containing inorganic polysilazane having a weight average molecular weight of 8,000 g/mol was obtained.

Example 2

A composition for forming a silica film containing inorganic polysilazane having a weight average molecular weight of 10,000 g/mol was obtained in the same manner as in Example 1, except that 380 g of dry pyridine and 140 g of dry xylene were used.

Example 3

A composition for forming a silica film containing inorganic polysilazane having a weight average molecular weight of 10,000 g/mol was obtained in the same manner as in Example 1, except that 410 g of dry pyridine and 180 g of dry xylene were used.

Example 4

100 g of the inorganic polysilazane semi-product (A) prepared in Synthesis Example 1, 350 g of dry pyridine, and 100 g of dry xylene were added to a reactor having a capacity of 1 L and equipped with a stirrer and a temperature controller, and while maintaining the reactor pressure at 1 bar, 120 A composition for forming a silica film containing inorganic polysilazane having a weight average molecular weight of 8,000 g/mol was finally obtained in the same manner as in Example 1 except for heating at °C.

Example 5

100 g of the inorganic polysilazane semi-product (A) prepared in Synthesis Example 1, 350 g of dry pyridine, 100 g of dry xylene, and 1000 cc of NH ₃ gas were added to the reactor with a stirrer and temperature controller having a capacity of 1 L, except that In the same manner as in Example 1, a composition for forming a silica film containing inorganic polysilazane having a weight average molecular weight of 10,000 g/mol was finally obtained.

Comparative Example 1

A composition for forming a silica film containing inorganic polysilazane having a weight average molecular weight of 5,500 g/mol was obtained in the same manner as in Example 1, except that 70 g of dry pyridine and 150 g of dry xylene were used.

Comparative Example 2

A composition for forming a silica film containing inorganic polysilazane having a weight average molecular weight of 6,500 g/mol was finally obtained in the same manner as in Example 1, except that 80 g of dry pyridine and 140 g of dry xylene were used.

Comparative Example 3

A composition for forming a silica film containing inorganic polysilazane having a weight average molecular weight of 10,000 g/mol was obtained in the same manner as in Example 1, except that 140 g of dry pyridine and 80 g of dry xylene were used.

Comparative Example 4

100 g of the inorganic polysilazane semi-product (A) prepared in Synthesis Example 1, 70 g of dry pyridine, and 150 g of dry xylene were introduced into a reactor with a stirrer and a temperature controller having a capacity of 1 L, and 120 g while maintaining the reactor pressure at 1 bar. A composition for forming a silica film containing inorganic polysilazane having a weight average molecular weight of 5,500 g/mol was finally obtained in the same manner as in Example 1, except that the heating was performed at °C.

Comparative Example 5

100 g of the inorganic polysilazane semi-product (A) prepared in Synthesis Example 1, 70 g of dry pyridine, 150 g of dry xylene, and 1000 cc of NH ₃ gas were added to the reactor with a stirrer and temperature controller having a capacity of 1 L. In the same manner as in Example 1, a composition for forming a silica film containing inorganic polysilazane having a weight average molecular weight of 5,500 g/mol was finally obtained.

Evaluation 1: Viscosity measurement

Viscosity was measured under the following conditions using a viscometer, model name LVDV3 manufactured by Brookfield.

In the present invention, the viscosity of each composition for forming a silica film was measured under the following conditions using a viscometer, model name LVDV3 manufactured by Brookfield.

<Measurement conditions>

(1) 50% concentrated solids

· Measurement temperature: 25℃ ±0.1℃

Spindle: CPE-40

Standard solution: 5.0 cps

· Torque: 45~55%

· RPM: 1 to 30

(2) 70% concentrated solids

· Measurement temperature: 25℃ ±0.1℃

Spindle: CPE-52

Standard solution: 990 cps

· Torque: 45~55%

· RPM: 1 to 30

After setting the above conditions, each sample concentrated to 50% solid content and 70% solid content of the compositions according to Examples 1 to 5 and Comparative Examples 1 to 5 was placed in a viscometer container using a syringe at 0.5 Injected ml by ml, and after reaching the measurement temperature, the viscosity was measured by inputting the torque range and RPM suitable for each sample, and the results are shown in Table 1 below.

Evaluation 2: Evaluation of thickness uniformity

The composition for forming a silica film according to Examples 1 to 5 and Comparative Examples 1 to 5 was applied with a spin coater (manufactured by MIKASA: MS-A200), the line width was 0.2 to 10 μm, and the space width was 0.2 μm. Each was coated on an 8-inch diameter wafer on which a pattern of ㎛ was formed.

Thereafter, after prebake at 150 ° C. for 3 minutes, the temperature was raised to 1,000 ° C. under an oxygen (O ₂ ) atmosphere, and cured for 1 hour under a H ₂ / O ₂ atmosphere at that temperature, Examples 1 to 5, and a silica membrane made of the compositions according to Comparative Examples 1 to 5.

After dicing the pattern wafer coated with the silica film in a radial form along the diameter, using SEM (Hitachi, SU-8230), TM (Thickness Monitoring, 90㎛ X 90㎛ ) site thickness was measured.

1 is a schematic diagram showing a location for measuring the thickness of a pattern wafer for thickness uniformity evaluation.

The TM site includes 17 radial dies as shown in FIG. 1, and the thickness was measured for a total of 85 points, 5 points per die.

After the first coating, the change with time was observed while coating was performed in 3-hour increments (Ohr, 3hr, 6hr, 9hr) up to 9 hours. During the waiting time, the nozzle was prevented from hardening by proceeding with a dummy dispense every 5 minutes, and the standard deviation of the thickness was calculated for a total of 12 sheets, 3 sheets each for each coating order, and the results are shown in Table 1 below.

Viscosity of Concentrated Solids
(unit: cps) thickness
Standard Deviation
(nm) 50% 70% viscosity difference
(70% solids - 50% solids) Example 1 22.7 860 837.3 7.5 Example 2 24.5 1305 1280.5 6.1 Example 3 26.8 1974 1947.2 5.2 Example 4 22.3 832.3 810 7.8 Example 5 23.1 894.7 871.6 7.1 Comparative Example 1 13.6 309.6 296 13.2 Comparative Example 2 17.3 363.1 345.8 12.5 Comparative Example 3 19.3 390.5 371.2 11.1 Comparative Example 4 13.1 284.2 271.1 13.7 Comparative Example 5 14.2 337.5 323.3 12.9

Referring to Table 1, the composition for forming a silica film according to Examples 1 to 5 has a viscosity difference between 70% concentrated solids and 50% concentrated solids in the range of 400 cps to 2,200 cps, and in this case, the thickness standard deviation is 10 nm, it can be seen that a uniform film thickness was formed.

On the other hand, in the compositions for forming a silica film according to Comparative Examples 1 to 5, the difference in viscosity between 70% concentrated solid content and 50% concentrated solid content is outside the scope of the present invention, and in this case, the thickness standard deviation exceeds 10 nm, so that the relative As a result, it can be confirmed that the thickness distribution of the silica film is not uniform.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concept of the present invention defined in the following claims are also made. It belongs to the scope of the present invention.

Claims (9)

comprising a silicon-containing polymer and a solvent;
A composition for forming a silica film wherein the difference between the viscosity of 70% concentrated solids and the viscosity of 50% concentrated solids is 400 cps to 2,200 cps. In paragraph 1,
A composition for forming a silica film having a viscosity of 450 cps to 2,300 cps of the 70% concentrated solids. In paragraph 1,
A composition for forming a silica film having a viscosity of 20 cps to 100 cps of the 50% concentrated solids. In paragraph 1,
The silicon-containing polymer is polysilazane, polysiloxazane, or a composition for forming a silica film of a combination thereof. In paragraph 4,
The polysilazane is an inorganic polysilazane composition for forming a silica film. In paragraph 1,
A composition for forming a silica film wherein the silicon-containing polymer has a weight average molecular weight of 4,000 g/mol to 20,000 g/mol. In paragraph 1,
The silicon-containing polymer is contained in an amount of 0.1 to 30% by weight based on the total amount of the composition for forming a silica film. A silica film prepared from the composition for forming a silica film according to any one of claims 1 to 7. An electronic device comprising the silica film according to claim 8 .

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