KR102504146B1 - Selectivity material and method of selective formation of thin film using selectivity material - Google Patents

Abstract

According to an embodiment of the present invention, a method of forming a region-selective thin film may include supplying a selectivity-imparting agent into a chamber in which a substrate is placed and adsorbing the selectivity-imparting agent to a non-growth region of the substrate; purging the inside of the chamber; a precursor supplying step of supplying a precursor to the inside of the chamber and adsorbing the precursor to the growth region of the substrate; purging the inside of the chamber; and forming a thin film by supplying a reactant into the chamber to react with the adsorbed precursor and forming a thin film.

Description

Area selective thin film formation method using selectivity imparting agent {SELECTIVITY MATERIAL AND METHOD OF SELECTIVE FORMATION OF THIN FILM USING SELECTIVITY MATERIAL}

The present invention relates to a method for forming a thin film, and more particularly, to a method for forming a region-selective thin film using a selectivity imparting agent.

Patterning of semiconductor devices is fabricated using the arrangement of various material layers and lithography or etching processes. However, over the past few decades, the miniaturization of devices has been accelerated and the required pattern size has decreased to the level of nanometers (nm), resulting in a significant increase in cost and time for nanopattern formation. In addition, various studies are being conducted on a selective deposition process capable of obtaining a self-aligned structure without the need to perform a subsequent process.

However, it is difficult to obtain the desired selectivity due to the formation of a subsequent film on the surface where inhibition is insufficient or undesirable. Accordingly, the present invention seeks to overcome the limitations of the prior art and provide an improved method for selective deposition of thin film materials using an ALD deposition process.

Korean Patent Publication No. 2007-0015958 (2007.02.06.)

An object of the present invention is to provide a method for forming a thin film that can be selected according to regions.

Other objects of the present invention will become more apparent from the detailed description that follows.

According to an embodiment of the present invention, a method of forming a region-selective thin film may include supplying a selectivity-imparting agent into a chamber in which a substrate is placed and adsorbing the selectivity-imparting agent to a non-growth region of the substrate; purging the inside of the chamber; a precursor supplying step of supplying a precursor to the inside of the chamber and adsorbing the precursor to the growth region of the substrate; purging the inside of the chamber; and forming a thin film by supplying a reactant into the chamber to react with the adsorbed precursor and forming a thin film.

The method may include, prior to the supplying of the selectivity imparting agent, contacting the substrate with a wet compound; rinsing the surface of the substrate with DI water; And drying the surface of the substrate may be further included.

The wet compound is selected from the group consisting of a composition comprising H2O2 (28% aq), NH4OH (28-30%) and H2O, HF, Peroxide, RCA clean chemical SC-1 / SC-2, H2SO4 / H2O2 mixture There can be more than one.

The growth region may be one or more thin films selected from the group consisting of SiO2, metal oxide, copper, cobalt, tungsten, amorphous silicon, polysilicon, monocrystalline silicon, germanium, and amorphous germanium hydride.

The non-growth region may be a silicon nitride layer.

The silicon nitride layer may be one or more selected from SiN, SiCN, C-doped SiN, and SiON.

The selectivity imparting agent may be represented by the following <Chemical Formula 1>.

<Formula 1>

In Formula 1, R1 is selected from an alkyl group having 1 to 8 carbon atoms, an aryl group, and a carboxylate, and R2 is selected from hydrogen, a halogen element, and an alkyl group having 1 to 8 carbon atoms.

The selectivity imparting agent may be represented by the following <Chemical Formula 2>.

<Formula 2>

In Formula 2, R is selected from hydrogen, a halogen element, an alkyl group having 1 to 8 carbon atoms, an alkyl group substituted with a halogen having 1 to 8 carbon atoms, and an aryl group having 6 to 10 carbon atoms.

The reactant may be any one of O3, O2, and H2O.

The precursor may be a compound containing Si.

According to an embodiment of the present invention, in a state in which the selectivity imparting agent is adsorbed in the non-growth region, the precursor supplied subsequently is prevented from adsorbing to the non-growth region, thereby preventing the formation of a thin film in the non-growth region. can In addition, through this, a self-aligned structure can be obtained without a subsequent process.

1 is a flowchart schematically illustrating a method of forming a thin film according to an embodiment of the present invention.
FIG. 2 is a graph schematically showing a supply cycle according to FIG. 1 .
FIG. 3 is a diagram schematically illustrating a thin film forming process according to FIG. 1 .
Figure 4 is a graph showing the thickness of the thin film according to an embodiment and a comparative example of the present invention.
5 is a table showing GPC according to an embodiment of the present invention and a comparative example.

Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to FIGS. 1 to 5 attached. Embodiments of the present invention may be modified in various forms, and the scope of the present invention should not be construed as being limited to the embodiments described below. These embodiments are provided to explain the present invention in more detail to those skilled in the art to which the present invention pertains. Accordingly, the shape of each element shown in the drawings may be exaggerated to emphasize a clearer description.

Throughout the present specification, when a certain component is said to "include", it means that it may further include other components without excluding other components unless otherwise stated.

As used throughout this specification, the terms "about," "substantially," and the like are used at or approximating that value when manufacturing and material tolerances inherent in the stated meaning are given, and do not convey the understanding of this application. Accurate or absolute figures are used to help prevent exploitation by unscrupulous infringers of the disclosed disclosure.

Throughout this specification, the term "alkyl" or "alkyl group" refers to 1 to 12 carbon atoms, 1 to 10 carbon atoms, 1 to 8 carbon atoms, 1 to 5 carbon atoms, 1 to 3 carbon atoms, includes linear or branched alkyl groups having 3 to 8 carbon atoms, or 3 to 5 carbon atoms. For example, the alkyl group includes a methyl group, an ethyl group, an n-propyl group ( ⁿ Pr), an iso-propyl group ( ⁱ Pr), an n-butyl group ( ⁿ Bu), a tert-butyl group ( ^t Bu), an iso- Butyl group ( ⁱ Bu), sec-butyl group ( ^s Bu), n-pentyl group, tert-pentyl group, iso-pentyl group, sec-pentyl group, neopentyl group, 3-pentyl group, hexyl group, isohex Examples include a sil group, a heptyl group, a 4,4-dimethylpentyl group, an octyl group, a 2,2,4-trimethylpentyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group, and isomers thereof, but are limited thereto It may not be.

Throughout the present specification, the term "film" may include "film" or "thin film", but may not be limited thereto.

In the conventional process, a film is accumulated in a non-growth region, for example, an unwanted region, and electrical characteristics and device characteristics may be deteriorated. However, the selectivity imparting agent described below is adsorbed to the silicon nitride film at a higher density than the silicon oxide film, and the selectivity imparting agent prevents the adsorption of a precursor introduced later to form a seed layer only on the silicon oxide film.

1 is a flowchart schematically illustrating a method of forming a thin film according to an embodiment of the present invention, and FIG. 2 is a graph schematically illustrating a supply cycle according to FIG. 1 . FIG. 3 is a diagram schematically illustrating a thin film forming process according to FIG. 1 .

A substrate is loaded into the process chamber, and the following ALD process conditions are adjusted. ALD process conditions may include temperature of the substrate or process chamber, chamber pressure, and gas flow rate, and the temperature is 10 to 900°C.

First, the substrate is exposed to the wet compound prior to the selectivating agent. The wet compound is one selected from the group consisting of H2O2 (28% aq), NH4OH (28-30%) and a composition comprising H2O, HF, Peroxide, RCA clean chemical SC-1 / SC-2, H2SO4 / H2O2 mixture may be ideal Thereafter, the substrate is rinsed with DI water or the like and then dried.

Next, the substrate is exposed to the selectivity imparting agent supplied into the chamber, and the selectivity imparting agent is adsorbed on the surface of the non-growth region of the substrate. The non-growth region may be a silicon nitride film, and may be one or more selected from SiN, SiCN, C-doped SiN, and SiON. In addition, the substrate has a growth region, and the growth region may be one or more thin films selected from the group consisting of SiO2, metal oxide, copper, cobalt, tungsten, amorphous silicon, polysilicon, monocrystalline silicon, germanium, and amorphous germanium hydride. The selectivity imparting agent is adsorbed at a high density on the surface of the non-growth region and prevents adsorption of the precursor in a subsequent process.

The selectivity imparting agent may be represented by the following <Chemical Formula 1>.

<Formula 1>

In Formula 1, R1 is selected from an alkyl group having 1 to 8 carbon atoms, an aryl group, and a carboxylate, and R2 is selected from hydrogen, a halogen element, and an alkyl group having 1 to 8 carbon atoms.

The selectivity imparting agent may be represented by the following <Chemical Formula 2>.

<Formula 2>

In Formula 2, R is selected from hydrogen, a halogen element, an alkyl group having 1 to 8 carbon atoms, an alkyl group substituted with a halogen having 1 to 8 carbon atoms, and an aryl group having 6 to 10 carbon atoms.

Thereafter, a purge gas (eg, an inert gas such as Ar) is supplied to the inside of the chamber to remove or purify unadsorbed selectivity imparting agents or by-products.

Thereafter, the substrate is exposed to the precursor supplied to the inside of the chamber, and the precursor is adsorbed to the surface of the growth region and not adsorbed to the surface of the non-growth region due to the selectivity imparting agent. The precursor may be a compound containing Si.

Thereafter, a purge gas (eg, an inert gas such as Ar) is supplied into the chamber to remove or purify unadsorbed precursors or by-products.

Thereafter, the substrate is exposed to the reactant supplied into the chamber, and a thin film is formed on the surface of the substrate. The reactant reacts with the precursor layer to form a thin film, the reactant may be O3, O2, or H2O gas, and an oxide film may be formed through the reactant.

Thereafter, a purge gas (eg, an inert gas such as Ar) is supplied into the chamber to remove or purify unreacted substances or by-products.

- Example 1

Pretreatment was performed on SiN and SiO substrates using 1.12 wt% of DHF as a wet compound. The heating mantle set temperature is 100 ℃, and after 12 hours of dipping, it was rinsed with isopropyl alcohol and DI water. N2 blowing was performed so that no solution was left on the surface of the substrate.

Propionaldehyde, a selectivity imparting agent described above, was supplied on the growth region substrate (SiO) and the non-growth region substrate (SiN), respectively, and then a silicon oxide film was formed. A silicon oxide film was formed through the ALD process, the ALD process temperature was 160 ° C, and O3 gas was used as a reaction material.

The silicon oxide film formation process through the ALD process is as follows, and the following process was performed as one cycle (see FIGS. 1 to 3).

1) A selectivity imparting agent is supplied into the reaction chamber and adsorbed onto the substrate

2) Ar gas is supplied into the reaction chamber to remove unadsorbed selectivity imparting agents or by-products

3) Using Ar as a carrier gas, silicon precursor DIPAS (Diisopropylamino Silane) is supplied to the reaction chamber and the silicon precursor is adsorbed on the substrate

4) Ar gas is supplied into the reaction chamber to remove unadsorbed silicon precursors or by-products

5) O3 gas is supplied to the reaction chamber to form a silicon oxide film

6) Ar gas is supplied into the reaction chamber to remove unreacted substances or by-products

- Comparative Example 1

A silicon oxide film was formed on the growth region substrate (SiO) and the non-growth region substrate (SiN), respectively, without using the aforementioned wet compound/selectivity imparting agent. A silicon oxide film was formed through the ALD process, the ALD process temperature was 160 ° C, and O3 gas was used as a reaction material.

The silicon oxide film formation process through the ALD process is as follows, and the following process was performed as one cycle.

1) Using Ar as a carrier gas, the silicon precursor DIPAS is supplied to the reaction chamber and the silicon precursor is adsorbed on the substrate

2) Ar gas is supplied into the reaction chamber to remove unadsorbed silicon precursors or by-products

3) O3 gas is supplied to the reaction chamber to form a silicon oxide film

4) Ar gas is supplied into the reaction chamber to remove unreacted substances or by-products

- Comparative Example 2

Pretreatment was performed on SiN and SiO substrates using 1.12 wt% of DHF as a wet compound. The heating mantle set temperature is 100 ℃, and after 12 hours of dipping, it was rinsed with isopropyl alcohol and DI water. N2 blowing was performed so that no solution was left on the surface of the substrate. Thereafter, a silicon oxide film was formed on the growth region substrate (SiO) and the non-growth region substrate (SiN) in the same manner as in Comparative Example 1 without using a selectivity imparting agent.

4 is a graph showing the thickness of a thin film according to an embodiment and a comparative example of the present invention, and FIG. 5 is a table showing GPC according to an embodiment and a comparative example of the present invention. The SiO thickness (A) in Comparative Example 1 was SiN substrate: SiO substrate = 69.97: 60.44, and the SiO thickness (A) in Comparative Example 2 was SiN substrate: SiO substrate = 62.48: 62.47, whereas in Example 1 the SiN substrate : Selectivity increased to SiO substrate = 6.36 : 58.42.

It can be seen that the thickness decreased by 6.48% in the SiO substrate, while the thickness decreased by 89.8% in the SiN substrate, and the selectivity increased. Such a result can be interpreted as suppressing deposition of the silicon precursor by adsorbing the selectivity imparting agent to the SiN substrate.

The reason why the selectivity imparting agent has selectivity in Example 1 is that it is structurally compatible with the SiN substrate and has enhanced adsorption, which is interpreted as delaying the nucleus growth of the thin film on the SiN substrate, and as a result of other complex causes, the desired selectivity can be obtained.

Although the present invention has been described in detail through examples above, other types of embodiments are also possible. Therefore, the spirit and scope of the claims set forth below are not limited to the embodiments.

Claims (10)

a selectivity imparting agent supplying step of supplying a selectivity imparting agent into a chamber in which a substrate is placed and adsorbing the selectivity imparting agent to a non-growth region of the substrate;
purging the inside of the chamber;
a precursor supplying step of supplying a precursor to the inside of the chamber and adsorbing the precursor to the growth region of the substrate;
purging the inside of the chamber; and
A thin film forming step of supplying a reactant to the inside of the chamber to react with the adsorbed precursor and forming a thin film,
The method of forming a region-selective thin film, wherein the selectivity imparting agent is represented by the following <Chemical Formula 1>.
<Formula 1>

In Formula 1, R1 is selected from an alkyl group having 1 to 8 carbon atoms, an aryl group, and a carboxylate, and R2 is selected from hydrogen, a halogen element, and an alkyl group having 1 to 8 carbon atoms. According to claim 1,
The method,
The method of forming a region-selective thin film, further comprising contacting the substrate with a wet compound prior to the supplying of the selectivity imparting agent. According to claim 2,
The wet compound,
At least one selected from the group consisting of H2O2 (28% aq), NH4OH (28-30%) and a composition comprising H2O, HF, Peroxide, RCA clean chemical SC-1 / SC-2, H2SO4 / H2O2 mixture, region selective thin film formation method. According to claim 1,
The growth region is at least one thin film selected from the group consisting of SiO2, metal oxide, copper, cobalt, tungsten, amorphous silicon, polysilicon, monocrystalline silicon, germanium and amorphous germanium hydride. According to claim 1,
The non-growth region is a silicon nitride film, region selective thin film forming method. According to claim 5,
Wherein the silicon nitride film is at least one selected from SiN, SiCN, C-doped SiN, and SiON. According to any one of claims 1 to 6,
Wherein the selectivity imparting agent is propionaldehyde, a method for forming a region-selective thin film. According to any one of claims 1 to 6,
Wherein the precursor is DIPAS, region selective thin film formation method. According to any one of claims 1 to 6,
The reaction material is any one of O3, O2, H2O, region selective thin film forming method. According to any one of claims 1 to 6,
The method of forming a region selective thin film, wherein the precursor is a compound containing Si.

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