JP6272033B2 - Method for producing silicon oxide or silicon oxynitride thin film by atomic layer deposition - Google Patents

Description

  The present invention relates to a method for producing a silicon oxide or silicon oxynitride thin film by an atomic layer deposition method.

  Silicon oxide and silicon oxynitride thin films are electronic members for electronic components such as interlayer insulating films, capacitor films, gate films, barrier films, and gate insulating films, and optical members for optical communication devices such as optical waveguides, optical switches, and optical amplifiers. Used as In recent years, along with higher integration and higher density of electronic devices, the above-mentioned electronic members and optical members have been miniaturized and refined, and methods for manufacturing silicon oxide and silicon oxynitride thin films that can handle this have been studied. Has been.

  Examples of the method for producing the silicon oxide or silicon oxynitride thin film include a coating pyrolysis method, a sol-gel method, a chemical vapor deposition method (hereinafter sometimes referred to as a CVD method), an atomic layer deposition method (hereinafter referred to as an ALD method). However, since it has many advantages such as excellent composition controllability, step coverage, suitable for mass production, and capable of hybrid integration, the CVD method, A method of vaporizing a precursor such as the ALD method is often used, and the ALD method is an optimum manufacturing method because the quality of the obtained silicon oxide or silicon oxynitride thin film is high.

Various methods for producing silicon oxide and silicon oxynitride thin films by the ALD method are conventionally known. For example, U.S. Patent No. 6,053,836 includes (a) positioning at least one substrate in a chamber, (b) exposing the at least one substrate to a silicon precursor, and (c) the at least one substrate. It is disclosed that silicon dioxide can be deposited at low temperatures by atomic deposition methods by a method comprising exposing the substrate to a pyridine soak solution and (d) exposing the at least one substrate to an oxidation source. ing. However, in order to adopt this method, it is essential to introduce a large-sized apparatus and the process is complicated, so the productivity is low, and in particular, a thin film with good film quality is a low temperature. When manufactured below, the problem is that the film thickness obtained per cycle becomes very thin.
Patent Document 2 discloses a silicon alkoxide compound suitable for a raw material for forming a thin film used in a method for forming a thin film by vaporizing a compound such as a CVD method. Moreover, ozone is mentioned as one of the reactive gases used for this method. However, Patent Document 2 discloses nothing specifically about the excellent effect obtained only when the silicon alkoxide compound and ozone gas are used in combination in the production of a silicon oxide or silicon oxynitride thin film by the ALD method. Not.

JP 2012-142611 A International Publication No. 2005/085175

  The properties required of a compound (precursor) suitable for a raw material for vaporizing a compound such as a CVD method to form a thin film are that the melting point is low and that it can be transported in a liquid state, the liquid has a low viscosity, and the vapor pressure is low. It is easy to vaporize greatly and has high thermal stability. In particular, when obtaining a silicon oxide or silicon oxynitride thin film by the ALD method, it is possible to obtain a good quality thin film with low productivity at a low temperature, and silicon oxide or oxynitride capable of obtaining a thin film over a wider temperature range. There has been a demand for a method for producing a silicon thin film. More specifically, the substrate temperature is high in productivity and good quality within a temperature range of 250 ° C. or lower from the temperature necessary for vaporizing the silicon compound and supplying it stably into the film forming chamber in which the substrate is installed. There has been a demand for a method for producing a silicon oxide or silicon oxynitride thin film by an atomic layer deposition method capable of obtaining a silicon oxide or silicon oxynitride thin film.

  As a result of repeated studies, the present inventor has found that a method for producing a silicon oxide or silicon oxynitride thin film by an atomic layer deposition method characterized by having a specific process can solve the above problems, and the present invention. Reached.

  That is, according to the present invention, in a method for producing a silicon oxide or silicon oxynitride thin film by an atomic layer deposition method, (A) a silicon compound represented by the following general formula (1) is supplied into a film forming chamber in which a substrate is installed. And (B) a step of supplying ozone into the film formation chamber in which the substrate is installed (hereinafter may be abbreviated as (B) step). The present invention provides a method for producing a silicon oxide or silicon oxynitride thin film by an atomic layer deposition method.

(In the formula, R ^{1 to} R ⁴ each independently represents hydrogen or a linear or branched alkyl group having 1 to 5 carbon atoms, and A represents an alkanediyl group having 1 to 8 carbon atoms.)

  According to the present invention, in a method for producing a silicon oxide or silicon oxynitride thin film by an atomic layer deposition method, the substrate temperature is supplied to the substrate stably by vaporizing the silicon compound represented by the general formula (1). Even when the temperature is in the range of 250 ° C. or lower from the temperature required for the above, a good quality silicon oxide or silicon oxynitride thin film can be obtained. More specifically, even when the substrate temperature is in the temperature range of 100 ° C. to 250 ° C., a good quality thin film can be obtained with high productivity.

FIG. 1 is a schematic diagram showing an example of an apparatus for an atomic layer deposition method used in a method for producing a silicon oxide or silicon oxynitride thin film by an atomic layer deposition method according to the present invention. FIG. 2 is a schematic diagram showing another example of an apparatus for atomic layer deposition used in the method for producing a silicon oxide or silicon oxynitride thin film by atomic layer deposition according to the present invention. FIG. 3 is a schematic view showing another example of an apparatus for an atomic layer deposition method used in the method for producing a silicon oxide or silicon oxynitride thin film by the atomic layer deposition method according to the present invention. FIG. 4 is a schematic diagram showing another example of an apparatus for atomic layer deposition used in the method for producing a silicon oxide or silicon oxynitride thin film by atomic layer deposition according to the present invention.

Hereinafter, a method for producing a silicon oxide or silicon oxynitride thin film by an atomic layer deposition method of the present invention will be described in detail based on preferred embodiments.
First, the silicon compound represented by the general formula (1) used in the step (A) in the production method of the present invention will be described.

In the general formula (1), R ^{1 to} R ⁴ each independently represent hydrogen or a linear or branched alkyl group having 1 to 5 carbon atoms. Examples of the linear or branched alkyl group having 1 to 5 carbon atoms represented by R ^{1 to} R ⁴ include methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl, isobutyl, pentyl, sec Examples include pentyl, tertiary pentyl, isopentyl, and neopentyl. In the general formula (I), the alkanediyl group having 1 to 8 carbon atoms represented by A may be a straight chain or may have one or more branches at any position. Such alkanediyl groups include methylene, ethylene, propane-1,3-diyl, propane-1,2-diyl, butylene, butane-1,3-diyl, butane-2,3-diyl, butane-1 , 2-diyl, pentane-1,5-diyl, pentane-1,3-diyl, pentane-1,4-diyl, pentane-2,3-diyl, hexane-1,6-diyl, hexane-1,2 -Diyl, hexane-1,3-diyl, hexane-1,4-diyl, hexane-2,5-diyl, hexane-2,4-diyl, hexane-3,4-diyl, heptylene, octylene, ethane-1 , 1-diyl, propane-2,2-diyl and the like.

In the general formula (1), R ^{1 to} R ⁴ and A are preferably those in which the silicon compound represented by the general formula (1) is in a liquid state and has a high vapor pressure under normal temperature and normal pressure. Specifically, when A is methylene or ethylene, it is preferable because of high vapor pressure, and when it is methylene, it is particularly preferable because of high vapor pressure. Further, R ¹ and R ^2, R ^1, when at least one of R ² is hydrogen, silicon oxide or silicon oxynitride when used in combination with ozone in the manufacture of silicon oxide or silicon oxynitride film It is preferable because the effect of reducing the temperature for producing the film is high.
In particular, when R ¹ is hydrogen and R ² is a linear or branched alkyl group having 1 to 5 carbon atoms, the temperature at which the silicon oxide or silicon oxynitride film is produced when used in combination with ozone The effect that can be lowered is preferable because it is high, and a methyl group is preferable because the above-described effect is particularly high. R ³ and R ⁴ are each preferably hydrogen or a linear or branched alkyl group having 1 to 3 carbon atoms because of high vapor pressure. In addition, when R ¹ is hydrogen, R ^{2 to} R ⁴ are methyl groups, and A is methylene, the vapor pressure is high and used in combination with ozone when producing a silicon oxide or silicon oxynitride film. In particular, it is particularly preferable since the effect of reducing the temperature for producing the silicon oxide or silicon oxynitride film is high.

  As a silicon compound represented by the general formula (1), for example, the following chemical formula No. 1-No. A silicon compound represented by 18 is mentioned. In the chemical formulas below, “Me” represents a methyl group, and “Et” represents an ethyl group.

  The silicon compound represented by the general formula (1) is not particularly limited by the production method, and is produced by applying a known reaction. As a production method, a known general alkoxide compound synthesis method using a corresponding amino alcohol can be applied. For example, inorganic salts such as silicon halides and nitrates or hydrates thereof, and corresponding alcohol compounds And an inorganic salt such as a halide of silicon or a nitrate thereof, or a hydrate thereof, in the presence of a base such as sodium, sodium hydride, sodium amide, sodium hydroxide, sodium methylate, ammonia or amine. , A method of reacting the corresponding alcohol compound with an alkali metal alkoxide such as sodium alkoxide, lithium alkoxide, potassium alkoxide, etc., an alkoxide compound of a low molecular alcohol such as silicon methoxide, ethoxide, isopropoxide, butoxide, and the corresponding alcohol compound And Method of conversion reaction, a halide of silicon, is reacted with a derivative giving the reactive intermediate with an inorganic salt of nitrate, a reactive intermediate, and a method of reacting the alcohol compound corresponding thereto. Examples of the reactive intermediate include tetrakis (dialkylamino) silicon, tetrakis (bis (trimethylsilyl) amino) silicon, silicon amide compounds, and the like.

  The form of the silicon compound represented by the general formula (1) is appropriately selected depending on the method of transport and supply used.

  As the transport and supply method, the silicon compound represented by the general formula (1) is vaporized by heating and / or decompressing in a raw material container, and a carrier such as argon, nitrogen, and helium used as necessary. A gas transport method for introducing into a film forming chamber (hereinafter sometimes referred to as a deposition reaction section) where a substrate is installed together with a gas, a silicon compound represented by the above general formula (1), a liquid or a solution In this state, there is a liquid transport method in which the material is transported to the vaporizing chamber, vaporized by heating and / or decompressing in the vaporizing chamber, and introduced into the film forming chamber. In the case of the gas transport method, it is the silicon compound itself represented by the general formula (1). In the case of the liquid transport method, the silicon compound itself represented by the general formula (1) or the compound is used as an organic solvent. These are dissolved solutions, which may further contain a nucleophilic reagent.

  As said organic solvent, it does not receive a restriction | limiting in particular, A well-known general organic solvent can be used. Examples of the organic solvent include acetates such as ethyl acetate, butyl acetate and methoxyethyl acetate; ethers such as tetrahydrofuran, tetrahydropyran, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, dibutyl ether and dioxane; Ketones such as butyl ketone, methyl isobutyl ketone, ethyl butyl ketone, dipropyl ketone, diisobutyl ketone, methyl amyl ketone, cyclohexanone, methylcyclohexanone; hexane, cyclohexane, methylcyclohexane, dimethylcyclohexane, ethylcyclohexane, heptane, octane, toluene, Hydrocarbons such as xylene; 1-cyanopropane, 1-cyanobutane, 1-cyanohexa , Hydrocarbons having a cyano group such as cyanocyclohexane, cyanobenzene, 1,3-dicyanopropane, 1,4-dicyanobutane, 1,6-dicyanohexane, 1,4-dicyanocyclohexane, 1,4-dicyanobenzene Pyridine, lutidine and the like, and these are used alone or as a mixed solvent of two or more kinds depending on the solubility of the solute, the relationship between the use temperature and boiling point, the flash point, and the like. When these organic solvents are used, the amount of the silicon compound represented by the general formula (1) in the organic solvent is 0.01 to 2.0 mol / liter, particularly 0.05 to 1.0 mol / liter. It is preferable to make it liter.

  Moreover, in the manufacturing method of this invention, in order to provide the stability of the silicon compound represented by the said General formula (1) as needed, you may contain a nucleophilic reagent. Examples of the nucleophilic reagent include ethylene glycol ethers such as glyme, diglyme, triglyme and tetraglyme, 18-crown-6, dicyclohexyl-18-crown-6, 24-crown-8, dicyclohexyl-24-crown-8. , Crown ethers such as dibenzo-24-crown-8, ethylenediamine, N, N′-tetramethylethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, 1,1,4,7,7- Polyamines such as pentamethyldiethylenetriamine, 1,1,4,7,10,10-hexamethyltriethylenetetramine and triethoxytriethyleneamine, cyclic polyamines such as cyclam and cyclen, pyridine, pyrrolidine and pipette Heterocyclic compounds such as gin, morpholine, N-methylpyrrolidine, N-methylpiperidine, N-methylmorpholine, tetrahydrofuran, tetrahydropyran, 1,4-dioxane, oxazole, thiazole, oxathiolane, methyl acetoacetate, ethyl acetoacetate, Β-ketoesters such as acetoacetate-2-methoxyethyl or β-diketones such as acetylacetone, 2,4-hexanedione, 2,4-heptanedione, 3,5-heptanedione, etc., and these nucleophilic properties The usage-amount of a reagent is normally used in 0.1 mol-10 mol with respect to 1 mol of silicon compounds represented by the said General formula (1), Preferably it is used in 1-4 mol.

The silicon compound represented by the general formula (1) used in the production method of the present invention contains as much as possible impurity metal elements other than the components constituting the compound, impurity halogen components such as impurity chlorine, and impurity organic components. Do not let it. The impurity metal element content is preferably 100 ppb or less for each element, more preferably 10 ppb or less, and the total amount is preferably 1 ppm or less, more preferably 100 ppb or less. In particular, when it is used as an LSI gate insulating film, gate film, or barrier layer, the content of alkali metal elements, alkaline earth metal elements, and related elements that affect the electrical characteristics of the resulting thin film may be reduced. is necessary. The impurity halogen content is preferably 100 ppm or less, more preferably 10 ppm or less, and still more preferably 1 ppm or less. The total amount of impurity organic components is preferably 500 ppm or less, more preferably 50 ppm or less, and still more preferably 10 ppm or less.
In addition, moisture is generated by the hydrolysis of the silicon compound represented by the general formula (1), and causes generation of particles during the formation of the thin film. Therefore, the metal compound, the organic solvent, and About a nucleophilic reagent, in order to reduce each water content, it is better to remove water as much as possible before use. The water content of each of the silicon compound, the organic solvent and the nucleophilic reagent represented by the general formula (1) is preferably 10 ppm or less, and more preferably 1 ppm or less.

  Moreover, the silicon compound represented by the general formula (1) used in the production method of the present invention is to prevent particles from being contained as much as possible in order to reduce or prevent particle contamination of the formed thin film. preferable. Specifically, in the particle measurement by the light scattering liquid particle detector in the liquid phase, the number of particles larger than 0.3 μm is preferably 100 or less in 1 ml of the liquid phase, and larger than 0.2 μm. The number of particles is more preferably 1000 or less in 1 ml of the liquid phase, and the number of particles larger than 0.2 μm is further preferably 100 or less in 1 ml of the liquid phase.

  The ozone gas used in step (B) in the production method of the present invention is not particularly limited, and may be a mixed gas with a gas such as argon, nitrogen, oxygen, hydrogen peroxide, water, ammonia and hydrogen. The concentration of ozone in the mixed gas in the case of the mixed gas is preferably 0.1 to 99.9% by mass.

  The manufacturing method of the present invention includes (A) a step of supplying a silicon compound represented by the general formula (1) into a film forming chamber in which a substrate is installed, and (B) a film forming chamber in which the substrate is installed. A method for producing a silicon oxide or silicon oxynitride thin film by an atomic layer deposition method having a step of supplying ozone gas. By using a production method in which the steps (A) and (B) are combined, the substrate temperature is expressed by the general formula ( It is possible to obtain a high-quality silicon oxide or silicon oxynitride thin film even in the temperature range from a temperature required to vaporize the silicon compound represented by 1) and stably supply it to the substrate to 250 ° C. The effect that it is possible can be produced. The method for transporting and supplying the silicon compound represented by the above general formula (1) and the manufacturing conditions and manufacturing apparatus of the atomic layer deposition method are not particularly limited, and well-known general conditions and methods may be used. it can.

In the step (A) in the production method of the present invention, the method for supplying the silicon compound represented by the general formula (1) into the film forming chamber in which the substrate is installed is not particularly limited, and is described above. The gas transport method, liquid transport method and the like can be used.
In addition, in the step (B) in the production method of the present invention, the method for supplying ozone gas into the film forming chamber in which the substrate is installed is not particularly limited, and for example, it can be supplied by pressure feeding.

  Examples of the material of the substrate include silicon; indium arsenide, indium gallium arsenide, silicon oxide, silicon nitride, silicon carbide, titanium nitride, tantalum oxide, tantalum nitride, titanium oxide, titanium nitride, ruthenium oxide, zirconium oxide, hafnium oxide, Ceramics such as lanthanum oxide and gallium nitride; glass; metals such as platinum ruthenium, aluminum, copper, nickel, cobalt, tungsten, and molybdenum. Examples of the shape of the substrate include a plate shape, a spherical shape, a fiber shape, and a scale shape, and the surface of the substrate may be a flat surface or a three-dimensional structure such as a trench structure.

  Examples of the production conditions of the atomic layer deposition method include supply conditions (vaporization temperature, vaporization pressure), substrate temperature (reaction temperature), reaction pressure, and the like of the silicon compound represented by the general formula (1).

  As a manufacturing apparatus for the atomic layer deposition method, a known atomic layer deposition method apparatus can be used. Specific examples of the apparatus include an apparatus capable of carrying a precursor as shown in FIG. 1 by bubbling supply, an apparatus having a vaporization chamber as shown in FIG. 2, and a reactive gas as shown in FIG. 3 or FIG. And an apparatus capable of performing plasma treatment. In addition, the present invention is not limited to the single wafer type apparatus as shown in FIGS. 1, 2, 3 and 4, and an apparatus capable of simultaneously processing a large number of sheets using a batch furnace can also be used.

  The production method of the present invention will be specifically described. First, the silicon compound represented by the above general formula (1) is supplied from the gas introduction port into the film forming chamber in which the substrate is installed on the support base by the above-described transportation supply method (raw material introduction step). As supply conditions of the silicon compound represented by the general formula (1), the vaporization temperature is preferably room temperature to 150 ° C., and the vaporization pressure is preferably 0.01 to 300 Pa. Next, a precursor thin film is formed on the surface of the substrate with the silicon compound represented by the general formula (1) introduced into the film formation chamber (deposition reaction part) where the substrate is installed (precursor thin film formation). Process). At this time, heat may be applied by heating the substrate or heating the deposition reaction part. The precursor thin film formed in this step is a silicon oxide or silicon oxynitride thin film or a thin film formed by decomposition and / or reaction of a part of the silicon compound represented by the general formula (1). The target silicon oxide or silicon oxynitride thin film has a different composition. The substrate temperature when this step is performed is preferably room temperature to 300 ° C, particularly preferably 100 ° C to 250 ° C.

  Next, the unreacted silicon compound gas represented by the general formula (1) and by-produced gas are exhausted from the deposition reaction part (exhaust process). The unreacted silicon compound gas represented by the general formula (1) and the by-produced gas are ideally exhausted completely from the deposition reaction part, but it is not always necessary to exhaust them completely. Examples of the exhaust method include a method of purging the system with an inert gas such as nitrogen, helium, and argon, a method of exhausting the system by depressurizing the system, a method combining these, and the like. When the pressure is reduced, the degree of pressure reduction is preferably 0.01 to 300 Pa, and more preferably 0.01 to 100 Pa.

  Next, ozone gas is supplied to the deposition reaction section by the above-described transport supply method, and a silicon oxide or silicon oxynitride thin film is formed from the precursor thin film obtained in the previous precursor thin film formation step by the action of ozone gas and heat. (Silicon oxide or silicon oxynitride thin film forming step). The temperature when heat is applied in this step is preferably room temperature to 300 ° C, more preferably 100 to 250 ° C. Depending on the desired composition of the silicon oxide or silicon oxynitride thin film, a reactive gas such as oxygen, hydrogen peroxide, water, ammonia and hydrogen may be mixed with ozone gas and supplied in advance. The deposition reaction unit may be supplied using a supply line different from ozone gas. When the reactive gas is supplied to the deposition reaction unit using a supply line different from the ozone gas, the reactive gas may be supplied to the deposition reaction unit before the ozone gas is supplied to the deposition reaction unit. The reactive gas may be supplied to the deposition reaction unit after the ozone gas is supplied to the deposition reaction unit. In the case where the reactive gas is supplied to the deposition reaction unit before the ozone gas is supplied to the deposition reaction unit, the reactive gas may be exhausted by the above-described exhaust method before the ozone gas is supplied. In addition, when the reactive gas is supplied to the deposition reaction unit after the ozone gas is supplied to the deposition reaction unit, the ozone gas may be exhausted by the above-described exhaust method before the reactive gas is supplied.

  In the production method of the present invention, a high-quality silicon oxide or silicon oxynitride thin film is produced even when the substrate temperature during the precursor thin film formation step and the silicon oxide or silicon oxynitride thin film formation step is 100 ° C. to 250 ° C. be able to.

  In the manufacturing method of the present invention, one cycle is a thin film deposition by a series of operations including the raw material introduction step, the precursor thin film formation step, the exhaust step, and the silicon oxide or silicon oxynitride thin film formation step, and this cycle is necessary. It may be repeated a plurality of times until a thin film with a sufficient thickness is obtained. In this case, after performing one cycle, in the same manner as in the exhaust process, after exhausting the silicon compound gas and ozone gas represented by the general formula (1) unreacted from the deposition reaction part, and further by-produced gas, It is preferable to perform the next one cycle.

  In the formation of a silicon oxide or silicon oxynitride thin film by an atomic layer deposition method, energy such as plasma, light, or voltage may be applied. The timing for applying these energies is not particularly limited. For example, when introducing the silicon compound gas represented by the above general formula (1) in the raw material introducing step, the precursor thin film forming step, or silicon oxide or silicon oxynitride It may be at the time of heating in the thin film forming process, at the time of exhausting in the system in the exhausting process, at the time of introducing ozone gas in the silicon oxide or silicon oxynitride thin film forming process, or between each of the above processes.

  In the manufacturing method of the present invention, after thin film deposition, annealing may be performed in an inert atmosphere, an oxidizing atmosphere, or a reducing atmosphere in order to obtain better electrical characteristics. If necessary, a reflow process may be provided. The temperature in this case is usually 200 to 1100 ° C, preferably 400 to 700 ° C.

Examples of the thin film produced by the production method of the present invention include a SiO ₂ film and a SiON thin film, and these applications include a high dielectric capacitor film, a gate insulating film, a gate film, a ferroelectric capacitor film, a capacitor film, and a barrier. Examples thereof include electronic component members such as membranes, and optical glass members such as optical fibers, optical waveguides, optical amplifiers, and optical switches.

  Hereinafter, the present invention will be described in more detail with reference to examples and evaluation examples. However, the present invention is not limited by the following examples.

[Examples 1 to 3] Production of silicon oxide thin film by ALD method 4 is a raw material for the ALD method, a reactive gas A (mixed gas of ozone 20% by mass and oxygen 80% by mass) is used as a reactive gas, and the vaporization conditions and substrate temperature shown in Table 1 using the apparatus shown in FIG. The silicon oxide thin film No. 1 was formed on the silicon wafer by the ALD method. 1-3 were produced. About the obtained thin film, when the thin film structure and the thin film composition were confirmed by the X-ray diffraction method and the X-ray photoelectron spectroscopy, the film composition was silicon oxide (SiO ₂ ) and the carbon content was detected. It was less than the lower limit of 0.1 atom%.
(Process)
A series of steps consisting of the following (1) to (4) was taken as one cycle and repeated 100 cycles.
(1) Compound No. vaporized under the conditions of vaporization temperature and vaporization chamber pressure of 100 Pa shown in Table 1. 4 is introduced and deposited on a silicon wafer heated to the substrate temperature shown in Table 1 at a system pressure of 100 Pa for 60 seconds.
(2) Unreacted raw materials are removed by argon purging for 10 seconds.
(3) Reactive gas A is introduced and reacted at a system pressure of 100 Pa for 60 seconds.
(4) Unreacted raw materials are removed by argon purging for 10 seconds.

[Comparative Production Examples 1 to 3] Production of silicon oxide thin film by ALD method Tetrakisdimethylaminosilane is used as a raw material for ALD method, reactive gas A is used as a reactive gas, and vaporization shown in Table 2 using the apparatus shown in FIG. Comparative films 1 to 3 were manufactured on a silicon wafer by the ALD method under conditions and substrate temperature conditions. About the obtained thin film, when the thin film structure and the thin film composition were confirmed by the X-ray diffraction method and the X-ray photoelectron spectroscopy, the film composition was silicon oxide (SiO ₂ ) and the carbon content was detected. It was less than the lower limit of 0.1 atom%.
(Process)
A series of steps consisting of the following (5) to (8) was taken as one cycle and repeated 100 cycles.
(5) Vapor of compound tetrakisdimethylaminosilane vaporized under the conditions of vaporization temperature and vaporization chamber pressure of 100 Pa shown in Table 1 is introduced and deposited on a silicon wafer heated to the substrate temperature shown in Table 1 at a system pressure of 100 Pa for 1 second. .
(6) Unreacted raw material is removed by argon purge for 10 seconds.
(7) Reactive gas A is introduced and reacted at a system pressure of 100 Pa for 10 seconds.
(8) Unreacted raw material is removed by argon purge for 10 seconds.

[Evaluation Example 1]
Silicon oxide thin film No. 1 obtained by Examples 1-3 and Comparative Examples 1-3. About 1-3 and the comparative films 1-3, the film thickness was measured by the X-ray reflectivity method, and the film thickness obtained per cycle was calculated. The results are shown in Table 2.

  From the results shown in Table 3, it was found that Evaluation Examples 1-1 to 1-3 had twice the film thickness obtained per cycle as compared with Comparative Examples 1-1 to 1-3. Thereby, it turned out that the manufacturing method of this invention is a manufacturing method which can obtain a silicon oxide thin film with sufficient productivity.

[Comparative Production Examples 4 to 9] Production of silicon oxide thin film by ALD method 4 was used as a raw material for the ALD method, water vapor or oxygen was used as a reactive gas, and an attempt was made to produce a thin film by the ALD method under the vaporization conditions and substrate temperature conditions shown in Table 4 using the apparatus shown in FIG. Even under the conditions, a thin film could not be obtained.
(Process)
A series of steps consisting of the following (9) to (12) was taken as one cycle and repeated 100 cycles.
(9) Compound No. vaporized under the conditions of vaporization temperature and vaporization chamber pressure of 100 Pa shown in Table 1. 4 is introduced and deposited on a silicon wafer heated to the substrate temperature shown in Table 4 at a system pressure of 100 Pa for 1 second.
(10) Unreacted raw materials are removed by argon purging for 10 seconds.
(11) Introduce water vapor or oxygen and react at a system pressure of 100 Pa for 10 seconds.
(12) Unreacted raw materials are removed by argon purging for 10 seconds.

  Part of this research was carried out at the University of Tokyo's “Ultrafine Lithography / Nano Measurement Center” with the support of the Ministry of Education, Culture, Sports, Science and Technology.

Claims (4)

In the method for producing a silicon oxide or silicon oxynitride thin film by an atomic layer deposition method,
(A) A step of supplying a silicon compound represented by the following general formula (1) into a film forming chamber in which the substrate is installed; and (B) ozone gas , argon gas, nitrogen in the film forming chamber in which the substrate is installed. gas, oxygen gas, possess hydrogen peroxide gas, water gas, a step of supplying a mixed gas of ammonia gas or hydrogen gas,
A method for producing a silicon oxide or silicon oxynitride thin film by an atomic layer deposition method, wherein the substrate temperature in the step of supplying a silicon compound and the step of supplying ozone gas is 100 ° C. or higher and 200 ° C. or lower .
(In the formula, R ^{1 to} R ⁴ each independently represents hydrogen or a linear or branched alkyl group having 1 to 5 carbon atoms, and A represents an alkanediyl group having 1 to 8 carbon atoms.) The method for producing a silicon oxide or silicon oxynitride thin film by an atomic layer deposition method according to claim ¹ , wherein R ^{1 in the} general formula (1) is hydrogen. The method for producing a silicon oxide or silicon oxynitride thin film by an atomic layer deposition method according to claim 2, wherein R ^{2 in the} general formula (1) is a linear or branched alkyl group having 1 to 5 carbon atoms. The method for producing a silicon oxide or silicon oxynitride thin film by an atomic layer deposition method according to claim 3, wherein R ^{2 in the} general formula (1) is a methyl group and A is methylene.