Thin film manufacturing method

Abstract

The present invention relates to a method for manufacturing a thin film, comprising: a step (i) for adsorbing a growth inhibitor for forming a thin film on the surface of a substrate; and (ii) a step of adsorbing a metal film precursor, a metal oxide film precursor, a metal nitride film precursor, or a silicon nitride film precursor on the surface of the substrate to which the growth inhibitor is adsorbed, the growth inhibitor for thin film formation being represented by Chemical Formula 1, the metal is one or more selected from the group consisting of tungsten, cobalt, chromium, aluminum, hafnium, vanadium, niobium, germanium, lanthanides, actinides, gallium, tantalum, zirconium, ruthenium, copper, titanium, nickel, iridium, and molybdenum. According to the method, the step coverage rate and the thickness uniformity of the thin film are greatly improved even if the thin film is formed on a substrate with a complex structure by inhibiting side reaction, reducing the growth rate of the thin film and removing process byproducts in the thin film. The chemical formula 1 is AnBmXo, wherein A is carbon or silicon, B is hydrogen or alkyl with the carbon atom number of 1-3, X is halogen, n is an integer of 1-15, o is an integer of more than 1, and m is 0-2n + 1.

Description

[0001] This application is a divisional application of the invention patent application with the application date of September 24, 2020, application number 202011015851.5, and invention name “Thin Film Manufacturing Method”. Technical Field

[0002] The present invention relates to a thin film manufacturing method, and more particularly to a thin film manufacturing method that significantly improves step coverage and thickness uniformity of a thin film by inhibiting side reactions, appropriately reducing a thin film growth rate, and removing process byproducts within the thin film to prevent corrosion and degradation, even when the thin film is formed on a substrate with a complex structure. Background Art

[0003] The integration level of storage and non-storage semiconductor devices is increasing day by day. As their structures become more and more complex, the importance of step coverage is increasing when depositing multiple thin films on a substrate.

[0004] The semiconductor thin film is formed of metal nitride, metal oxide, metal silicide, etc. The metal nitride thin film includes titanium nitride (TiN), tantalum nitride (TaN), zirconium nitride (ZrN) and other thin films, which are generally used as diffusion barriers between the silicon layer of the doped semiconductor and aluminum (Al), copper (Cu) and other materials used as interlayer wiring. However, when a tungsten (W) thin film is deposited on a substrate, it is used as an adhesion layer.

[0005] In order to obtain excellent and uniform physical properties of the thin film deposited on the substrate, the formed thin film needs to have excellent step coverage. Therefore, compared with the chemical vapor deposition (CVD) process that mainly uses gas phase reactions, the atomic layer deposition (ALD) process that uses surface reactions is more often used, but there are still problems in achieving 100% step coverage.

[0006] In addition, titanium tetrachloride (TiCl4) is used to deposit titanium nitride (TiN), which is a representative metal nitride. At this time, process byproducts such as chlorides will remain in the manufactured film, thereby inducing corrosion of metals such as aluminum and causing degradation of film quality due to the generation of non-volatile byproducts.

[0007] Therefore, it is necessary to develop a method for manufacturing a thin film that can form a thin film with a complex structure without corroding the interlayer wiring material.

[0008] Prior Art Literature

[0009] Patent Literature

[0010] (Patent Document 0001) Korean Patent Publication No. 2006-0037241 Summary of the invention

[0011] Technical issues

[0012] In order to solve the problems of the prior art as described above, the object of the present invention is to provide a thin film manufacturing method, which can appropriately reduce the thin film growth rate by inhibiting side reactions and prevent corrosion and degradation by removing process by-products in the thin film. Even when the thin film is formed on a substrate with a complex structure, the step coverage and thickness uniformity of the thin film are greatly improved.

[0013] The above-mentioned object and other objects of the present invention can be achieved by the present invention described below.

[0014] Technical Solution

[0015] In order to achieve the above-mentioned object, the present invention provides a thin film manufacturing method, which comprises: step (i), allowing a growth inhibitor for thin film formation to be adsorbed on a substrate surface; and step (ii), allowing a metal film precursor, a metal oxide film precursor, a metal nitride film precursor or a silicon nitride film precursor to be adsorbed on the substrate surface adsorbed with the growth inhibitor for thin film formation, wherein the growth inhibitor for thin film formation is represented by chemical formula 1, and the metal is one or more selected from tungsten, cobalt, chromium, aluminum, hafnium, vanadium, niobium, germanium, lanthanides, actinides, gallium, tantalum, zirconium, ruthenium, copper, titanium, nickel, iridium and molybdenum,

[0016] Chemical formula 1:

[0017] A n B m X o

[0018] Wherein, A is carbon or silicon, B is hydrogen or an alkyl group having 1 to 3 carbon atoms, X is a halogen, n is an integer from 1 to 15, o is an integer greater than 1, and m is 0 to 2n+1.

[0019] In addition, the present invention provides a thin film manufacturing device, which includes: an ALD (atomic layer deposition) chamber; a first vaporizer, which vaporizes a growth inhibitor for thin film formation; a first transfer unit, which transfers the vaporized growth inhibitor for thin film formation into the ALD chamber; a second vaporizer, which vaporizes a metal film precursor, a metal oxide film precursor, a metal nitride film precursor or a silicon nitride film precursor; and a second transfer unit, which transfers the vaporized precursor into the ALD chamber.

[0020] Beneficial Effects

[0021] The present invention provides a thin film manufacturing method, which appropriately reduces the film growth rate by inhibiting side reactions and reducing the deposition rate, and prevents corrosion and degradation by removing process byproducts in the thin film. Even when the thin film is formed on a substrate with a complex structure, the step coverage and the thickness uniformity of the thin film are greatly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a process diagram for explaining a conventional ALD process.

[0023] Figure 2 It is a process diagram for explaining an ALD process according to an embodiment of the present invention.

[0024] Figure 3 It is a graph showing the change in film thickness of Example 7 (SP-TiCl4) of the present invention and Comparative Example 1 (TiCl4) as the ALD cycle increases.

[0025] Figure 4 It is a graph showing the change in deposition rate of Examples 7-1 to 7-3 of the present invention and Comparative Example 1 depending on the feeding time of a growth inhibitor (SP) for thin film formation per ALD cycle.

[0026] Figure 5 These are transmission electron microscope (TEM) images of the TiN thin films deposited in Example 1 (SP-TiCl4) of the present invention and Comparative Example 1 (TiCl4).

[0027] Figure 6 The deposition rate of the additional embodiment 2 of the present invention and the additional comparative example 1 is shown. A graph showing the change in feeding time (s) of growth inhibitor (SP) for thin film formation per ALD cycle. DETAILED DESCRIPTION

[0028] Hereinafter, the thin film production method of the present invention will be described in detail.

[0029] The inventors of the present invention have confirmed that when a halogenated compound with a specified structure is first adsorbed on the surface of a substrate loaded inside an ALD chamber as a growth inhibitor before the film precursor compound is adsorbed on the surface of the substrate, the growth rate of the thin film formed after deposition is reduced, and the halide remaining as a process by-product is greatly reduced, thereby greatly improving the step coverage, etc. Based on this, further research was conducted and the present invention was completed.

[0030] The thin film manufacturing method of the present invention comprises: step (i), allowing a growth inhibitor for thin film formation to be adsorbed on a substrate surface; and step (ii), allowing a metal film precursor, a metal oxide film precursor, a metal nitride film precursor or a silicon nitride film precursor to be adsorbed on the substrate surface adsorbed with the growth inhibitor for thin film formation, wherein the growth inhibitor for thin film formation is represented by chemical formula 1, and the metal is one or more selected from tungsten, cobalt, chromium, aluminum, hafnium, vanadium, niobium, germanium, lanthanide elements, actinide elements, gallium, tantalum, zirconium, ruthenium, copper, titanium, nickel, iridium and molybdenum,

[0031] Chemical formula 1:

[0032] A n B m X o

[0033] Wherein, A is carbon or silicon, B is hydrogen or an alkyl group having 1 to 3 carbon atoms, X is a halogen, n is an integer from 1 to 15, o is an integer greater than 1, and m is 0 to 2n+1. In this case, when a thin film is formed, the film growth rate is reduced by suppressing side reactions, and corrosion and degradation are reduced by removing process byproducts in the thin film, so that even when a thin film is formed on a substrate with a complex structure, the step coverage and the thickness uniformity of the thin film are greatly improved.

[0034] In the step (i) of adsorbing the growth inhibitor for thin film formation on the surface of the substrate, the feeding time (Feeding Time) of the growth inhibitor for thin film formation to the surface of the substrate per cycle is preferably 1 to 10 seconds, more preferably 1 to 5 seconds, more preferably 2 to 5 seconds, and further preferably 2 to 4 seconds. Within this range, the thin film growth rate is low, and the step coverage and economy are excellent.

[0035] In the present invention, the feeding time of the growth inhibitor for thin film formation is based on a chamber volume of 15 to 20 L and a flow rate of 0.5 to 5 mg / s, more specifically, a chamber volume of 18 L and a flow rate of 1 to 2 mg / s.

[0036] As a preferred example, the step (i) of allowing the growth inhibitor for thin film formation to be adsorbed on the surface of the substrate may include the step of injecting the growth inhibitor for thin film formation into the ALD chamber and allowing it to be adsorbed on the surface of the loaded substrate. In this case, the thin film growth rate is reduced and the process by-products in the thin film are removed by suppressing side reactions and reducing the deposition rate.

[0037] In the step (i) of adsorbing the growth inhibitor for thin film formation on the surface of the substrate, it is preferred to use a purge gas to purge the residual growth inhibitor for thin film formation that has not been adsorbed on the surface of the substrate. At this time, the advantage is that when the thin film is formed, the film growth rate is reduced by inhibiting side reactions, and corrosion and degradation are reduced by removing process by-products in the thin film. Even when the thin film is formed on a substrate with a complex structure, the step coverage and the thickness uniformity of the thin film are greatly improved.

[0038] In addition, in the step (ii) of adsorbing the metal film precursor, metal oxide film precursor, metal nitride film precursor or silicon nitride film precursor (hereinafter referred to as "film precursor"), it is preferred to purge the unadsorbed residual precursor using a purge gas.

[0039] The thin film manufacturing method may preferably include the following steps: supplying a reaction gas after the film precursor is adsorbed on the surface of the substrate; and purging reaction byproducts of the film precursor and the reaction gas with a purge gas.

[0040] As a preferred embodiment, the thin film manufacturing method may include the following steps: (a) vaporizing the growth inhibitor for thin film formation and adsorbing it onto the surface of the substrate loaded in the ALD chamber; (b) purging the inside of the ALD chamber for the first time with a purge gas; (c) vaporizing the film precursor and adsorbing it onto the surface of the substrate loaded in the ALD chamber; (d) purging the inside of the ALD chamber for the second time with a purge gas; (e) supplying a reaction gas to the inside of the ALD chamber; and (f) purging the inside of the ALD chamber for the third time with a purge gas. In this case, the advantage is that the film growth rate is appropriately reduced, and even if the deposition temperature is increased when the film is formed, the generated process byproducts are effectively removed, thereby reducing the resistivity of the film and greatly improving the step coverage.

[0041] The thin film formation growth inhibitor and the film precursor may be preferably transferred into the ALD chamber, that is, onto the substrate surface, by a VFC method, a DLI method, or a LDS method, and more preferably transferred into the ALD chamber by an LDS method.

[0042] The ratio of the amount (mg / cycle) of the growth inhibitor for thin film formation to the amount of film precursor compound input into the ALD chamber can be preferably 1:1.5 to 1:20, more preferably 1:2 to 1:15, even more preferably 1:2 to 1:12, and further preferably 1:2.5 to 1:10. Within this range, the reduction rate of the thin film growth rate per cycle (GPC) is high and the effect of reducing process by-products is good.

[0043] When the film precursor is a film precursor commonly used in ALD (atomic layer deposition method), there is no particular limitation.

[0044] As an example, the metal film precursor, metal oxide film precursor and metal nitride film precursor can be respectively selected from one or more of metal halides, metal alkoxides, alkyl metal compounds, metal amide compounds, metal carbonyl compounds and substituted or unsubstituted cyclopentadienyl metal compounds, but are not limited thereto.

[0045] As a specific example, the metal film precursor, the metal oxide film precursor, and the metal nitride film precursor can be selected from tetrachlorotitan, tetrachlorogermanium, tetrachlorotin, tris(isopropyl)ethylmethylaminogermanium, tetraethoxygermanium, tetramethyltin, tetraethyltin, bisacetylacetonate tin, trimethylaluminum, tetrakis(dimethylamino)germanium, bis(n-butylamino)germanium, tetrakis(ethylmethylamino)tin, tetrakis(dimethylamino)tin, Co2(CO)8(dicobalt octacarbonyl, dicobalt The invention can be one or more of, but is not limited to, Cp2Co (biscyclopentadienylcobalt), Co(CO)3(NO) (cobalt tricarbonylnitrosyl) and CpCo(CO)2 (cobalt dicarbonyl cyclopentadienyl).

[0046] As an example, the silicon nitride film precursor may be selected from (NH2)Si(NHMe)3, (NH2)Si(NHEt)3, (NH2)Si(NH n pr)3、(NH2)Si(NH i pr)3、(NH2)Si(NH n bu)3、(NH2)Si(NH i bu)3、(NH2)Si(NHt bu)3、(NMe2)Si(NHMe)3、(NMe2)Si(NHEt)3、(NMe2)Si(NH n pr)3、(NMe2)Si(NH i pr)3、(NMe2)Si(NH n bu)3、(NMe2)Si(NH i bu)3、(NMe2)Si(NH t bu)3、(NEt2)Si(NHMe)3、(NEt2)Si(NHEt)3、(NEt2)Si(NH n pr)3、(NEt2)Si(NH i pr)3、(NEt2)Si(NH n bu)3、(NEt2)Si(NH i bu)3、(NEt2)Si(NH t bu)3、(N n pr2)Si(NHMe)3、(N n pr2)Si(NHEt)3、(N n pr2)Si(NH n pr)3、(N n pr2)Si(NH i pr)3、(N n pr2)Si(NH n bu)3、(N n pr2)Si(NH i bu)3、(N n pr2)Si(NH t bu)3、(N i pr2)Si(NHMe)3、(N i pr2)Si(NHEt)3、(N i pr2)Si(NH n pr)3、(N i pr2)Si(NH i pr)3、(N i pr2)Si(NH n bu)3、(N i pr2)Si(NH i bu)3、(N i pr2)Si(NH t bu)3、(N n bu2)Si(NHMe)3、(N n bu2)Si(NHEt)3、(N n bu2)Si(NH npr)3、(N n bu2)Si(NH i pr)3、(N n bu2)Si(NH n bu)3、(N n bu2)Si(NH i bu)3、(N n bu2)Si(NH t bu)3、(N i bu2)Si(NHMe)3、(N i bu2)Si(NHEt)3、(N i bu2)Si(NH n pr)3、(N i bu2)Si(NH i pr)3、(N i bu2)Si(NH n bu)3、(N i bu2)Si(NH i bu)3、(N i bu2)Si(NH t bu)3、(N t bu2)Si(NHMe)3、(N t bu2)Si(NHEt)3、(N t bu2)Si(NH n pr)3、(N t bu2)Si(NH i pr)3、(N t bu2)Si(NH n bu)3、(N t bu2)Si(NH i bu)3、(N t bu2)Si(NH t bu)3、(NH2)2Si(NHMe)2、(NH2)2Si(NHEt)2、(NH2)2Si(NH n pr)2、(NH2)2Si(NH i pr)2、(NH2)2Si(NH n bu)2、(NH2)2Si(NH i bu)2、(NH2)2Si(NH t bu)2、(NMe2)2Si(NHMe)2、(NMe2)2Si(NHEt)2、(NMe2)2Si(NH n pr)2、(NMe2)2Si(NH i pr)2、(NMe2)2Si(NHn bu)2、(NMe2)2Si(NH i bu)2、(NMe2)2Si(NH t bu)2、(NEt2)2Si(NHMe)2、(NEt2)2Si(NHEt)2、(NEt2)2Si(NH n pr)2、(NEt2)2Si(NH i pr)2、(NEt2)2Si(NH n bu)2、(NEt2)2Si(NH i bu)2、(NEt2)2Si(NH t bu)2、(N n pr2)2Si(NHMe)2、(N n pr2)2Si(NHEt)2、(N n pr2)2Si(NH n pr)2、(N n pr2)2Si(NH i pr)2、(N n pr2)2Si(NH n bu)2、(N n pr2)2Si(NH i bu)2、(N n pr2)2Si(NH t bu)2、(N i pr2)2Si(NHMe)2、(N i pr2)2Si(NHEt)2、(N i pr2)2Si(NH n pr)2、(N i pr2)2Si(NH i pr)2、(N i pr2)2Si(NH n bu)2、(N i pr2)2Si(NH i bu)2、(N i pr2)2Si(NH t bu)2、(N n bu2)2Si(NHMe)2、(N n bu2)2Si(NHEt)2、(N n bu2)2Si(NH n pr)2、(N n bu2)2Si(NH i pr)2、(N n bu2)2Si(NH n bu)2、(Nn bu2)2Si(NH i bu)2、(N n bu2)2Si(NH t bu)2、(N i bu2)2Si(NHMe)2、(N i bu2)2Si(NHEt)2、(N i bu2)2Si(NH n pr)2、(N i bu2)2Si(NH i pr)2、(N i bu2)2Si(NH n bu)2、(N i bu2)2Si(NH i bu)2、(N i bu2)2Si(NH t bu)2、(N t bu2)2Si(NHMe)2、(N t bu2)2Si(NHEt)2、(N t bu2)2Si(NH n pr)2、(N t bu2)2Si(NH i pr)2、(N t bu2)2Si(NH n bu)2、(N t bu2)2Si(NH i bu)2、(N t bu2)2Si(NH t bu)2、Si(HNCH2CH2NH)2、Si(MeNCH2CH2NMe)2、Si(EtNCH2CH2NEt)2、Si( n prNCH2CH2N n pr)2、Si( i prNCH2CH2N i pr)2、Si( n buNCH2CH2N n bu)2、Si( i buNCH2CH2N i bu)2、Si( t buNCH2CH2N t bu)2、Si(HNCHCHNH)2、Si(MeNCHCHNMe)2、Si(EtNCHCHNEt)2、Si( n prNCHCHN n pr)2、Si(i prNCHCHN i pr)2、Si( n this is my name n it)2、Si( i this is my name i it)2、Si( t this is my name t bu)2、(HNCHCHNH)Si(HNCH2CH2NH)、(MeNCHCHNMe)Si(MeNCH2CH2NMe)、(EtNCHCHNEt)Si(EtNCH2CH2NEt)、( n prNCHCHN n pr)Si( n prNCH2CH2N n pr)、( i prNCHCHN i pr)Si( i prNCH2CH2N i pr)、( n this is my name n it (Si) n thisNCH2CH2N n this)、( i this is my name i it (Si) i thisNCH2CH2N i this)、( t this is my name t it (Si) t thisNCH2CH2N t this)、(NH t bu)2Si(HNCH2CH2NH) 、(NH t bu)2Si(MeNCH2CH2NMe) 、(NH t bu)2Si(EtNCH2CH2NEt)、(NH t this)2Si( n prNCH2CH2N n pr) 、(NH t this)2Si( i prNCH2CH2N i pr)、(NH t this)2Si( n thisNCH2CH2N n this) 、(NH t this)2Si( ibuNCH2CH2N i bu)、 (NH t bu)2Si( t buNCH2CH2N t bu) 、(NH t bu)2Si(HNCHCHNH) 、 (NH t bu)2Si(MeNCHCHNMe) 、(NH t bu)2Si(EtNCCHCHNEt) 、 (NH t bu)2Si( n prNCHCHN n pr) 、(NH t bu)2Si( i prNCHCHN i pr) 、(NH t bu)2Si( n buNCHCHN n bu) 、(NH t bu)2Si( i buNCHCHN i bu) 、 (NH t bu)2Si( t buNCHCHN t bu) 、( i prNCH2CH2N i pr)Si(NHMe)2 、 ( i prNCH2CH2N i pr)Si(NHEt)2 、( i prNCH2CH2N i pr)Si(NH n pr)2、 ( i prNCH2CH2N i pr)Si(NH i pr)2 、( i prNCH2CH2N i pr)Si(NH n bu)2 、 ( i prNCH2CH2N i pr)Si(NH i bu)2 、( i prNCH2CH2N i pr)Si(NH t bu)2 、 ( i prNCHCHN i pr)Si(NHMe)2 、( iprNCH i pr)Si(NHEt)2, ( i prNCH i pr)Si(NH n pr)2, ( i prNCH i pr)Si(NH i pr)2, ( i prNCH i pr)Si(NH n bu)2、( i prNCH i pr)Si(NH i bu)2 and ( i prNCH i pr)Si(NH t bu)2 or more, but not limited to these.

[0047] Said n Pr represents n-propyl, i Pr represents isopropyl, n Bu represents n-butyl, i Bu represents isobutyl, t Bu represents tert-butyl.

[0048] As a preferred example, the metal halide may be titanium tetrahalide. As a specific example, it may be at least one selected from TiF4, TiCl4, TiBr4 and TiI4. For example, TiCl4 is preferred in terms of economy, but is not limited thereto.

[0049] However, since the titanium tetrahalide has excellent thermal stability, does not decompose at room temperature and exists in a liquid state, it can be well used as a film precursor for the ALD (atomic layer deposition) method to deposit a thin film.

[0050] As an example, the film precursor may be mixed with a nonpolar solvent and introduced into the chamber. In this case, the viscosity and vapor pressure of the film precursor can be easily adjusted.

[0051] The non-polar solvent may preferably be one or more selected from alkanes and cycloalkanes. In this case, an organic solvent having low reactivity and solubility and easy moisture management is contained, and step coverage is improved even when the deposition temperature is increased during film formation.

[0052] As a more preferred example, the non-polar solvent may include C1-C10 alkane or C3-C10 cycloalkane, preferably C3-C10 cycloalkane. In this case, the reactivity and solubility are low and moisture management is easy.

[0053] In the present invention, C1, C3, etc. represent the number of carbon atoms.

[0054] The cycloalkane may preferably be a C3-C10 monocycloalkane. Among the monocycloalkane, cyclopentane is liquid at room temperature and has the highest vapor pressure. Therefore, it is preferred in the vapor deposition process, but is not limited thereto.

[0055] As an example, the solubility of the non-polar solvent in water (25° C.) is less than 200 mg / L, preferably 50 to 200 mg / L, and more preferably 135 to 175 mg / L. Within this range, the reactivity to the membrane precursor is low and moisture management is easy.

[0056] In the present invention, when the solubility is based on a commonly used measurement method or benchmark in the technical field to which the present invention belongs, there is no particular limitation. As an embodiment, a saturated solution can be measured by HPLC.

[0057] Based on the total weight of the film precursor and the non-polar solvent, the content of the non-polar solvent may be preferably 5 to 95 wt %, more preferably 10 to 90 wt %, even more preferably 40 to 90 wt %, most preferably 70 to 90 wt %.

[0058] When the content of the non-polar solvent is greater than the above upper limit, impurities will be generated, resulting in an increase in the resistance and impurity values ​​in the film. When the content of the organic solvent is less than the above lower limit, the effect of increasing the step coverage and reducing impurities such as chloride (Cl) ions caused by adding the solvent is not good.

[0059] As an example, in the thin film manufacturing method, the thin film growth rate per cycle calculated by Mathematical Formula 1 is The reduction rate is below -5%, preferably below -10%, more preferably below -20%, even more preferably below -30%, further preferably below -40%, and most preferably below -45%. Within this range, the step coverage and film thickness uniformity are excellent.

[0060] Mathematical formula 1:

[0061] Reduction rate of thin film growth rate per cycle (%) = [(thin film growth rate per cycle when using a thin film formation growth inhibitor - thin film growth rate per cycle when not using a thin film formation growth inhibitor) / thin film growth rate per cycle when not using a thin film formation growth inhibitor] × 100

[0062] In the thin film manufacturing method, the residual halogen intensity (c / s) in the thin film formed after 200 cycles based on SIMS measurement can be preferably less than 10,000, more preferably less than 8,000, more preferably less than 7,000, and further preferably less than 6,000. Within this range, the effect of preventing corrosion and degradation is excellent.

[0063] In the present invention, the purge is preferably 1,000 to 10,000 sccm, more preferably 2,000 to 7,000 sccm, and even more preferably 2,500 to 6,000 sccm, within which the film growth rate per cycle is reduced to a preferred range and process byproducts are reduced.

[0064] The ALD (atomic layer deposition) process is very advantageous in the production of integrated circuits (ICs) that require a high aspect ratio, especially because it is based on a self-limiting thin film growth mechanism and has the advantages of excellent step conformality, uniform coverage, and precise thickness control.

[0065] As an example, the thin film manufacturing method can be implemented at a deposition temperature in the range of 50 to 900°C, preferably in the range of 300 to 700°C, more preferably in the range of 350 to 600°C, even more preferably in the range of 400 to 550°C, and further preferably in the range of 400 to 500°C. Within this range, the ALD process characteristics can be achieved and a thin film with excellent film quality can be grown.

[0066] As an embodiment, the thin film manufacturing method can be implemented at a steam pressure ranging from 0.1 to 10 Torr, preferably at a steam pressure ranging from 0.5 to 5 Torr, and more preferably at a steam pressure ranging from 1 to 3 Torr. Within this range, a thin film with uniform thickness can be obtained.

[0067] In the present invention, the deposition temperature and the deposition pressure may be measured by the temperature and pressure in the deposition chamber, or by the temperature and pressure applied to the substrate in the deposition chamber.

[0068] The thin film manufacturing method may preferably include: a step of raising the temperature in the chamber to the deposition temperature before introducing the growth inhibitor for thin film formation into the chamber; and / or a step of injecting an inert gas into the chamber for purging before introducing the growth inhibitor for thin film formation into the chamber.

[0069] In addition, the present invention relates to a thin film manufacturing device, which can implement the thin film manufacturing method, including: an ALD chamber; a first vaporizer, which vaporizes a growth inhibitor for thin film formation; a first transfer unit, which transfers the vaporized growth inhibitor for thin film formation into the ALD chamber; a second vaporizer, which vaporizes a metal film precursor, a metal oxide film precursor, a metal nitride film precursor, or a silicon nitride film precursor; and a second transfer unit, which transfers the vaporized precursor into the ALD chamber. There is no particular limitation when the vaporizer and the transfer unit are commonly used in the technical field to which the present invention belongs.

[0070] The thin film manufacturing method will be described using a specific example.

[0071] First, a substrate on which a thin film is to be formed is placed in a deposition chamber capable of performing atomic layer deposition.

[0072] The substrate may include a semiconductor substrate such as a silicon substrate or silicon oxide.

[0073] The substrate may further have a conductive layer or an insulating layer formed on an upper portion thereof.

[0074] In order to deposit a thin film on the substrate in the deposition chamber, the growth inhibitor for thin film formation and a film precursor or a mixture of the film precursor and a non-polar solvent are prepared separately.

[0075] Then, the prepared thin film forming inhibitor is injected into the vaporizer, converted into a vapor phase, and transferred to the deposition chamber, where it is adsorbed onto the substrate, and the unadsorbed thin film forming inhibitor is purged.

[0076] Then, the prepared film precursor or a mixture of the film precursor and a non-polar solvent is injected into a vaporizer, converted into a vapor phase, and transferred to a deposition chamber to be adsorbed onto a substrate, thereby purging the unadsorbed thin film forming composition.

[0077] As an example, in the present invention, the method for transferring the inhibitor for thin film formation and the film precursor to the deposition chamber can adopt a method of transferring the volatilized gas (Vapor Flow Control; VFC) using a gas phase flow control (Mass Flow Controller; MFC) method or a method of transferring the liquid (Liquid Delivery System; LDS) using a liquid phase flow control (Liquid Mass Flow Controller; LMFC) method, and the LDS method is preferably used.

[0078] At this time, the carrier gas or dilution gas used to transfer the thin film forming inhibitor and film precursor to the substrate can be one or a mixed gas selected from argon (Ar), nitrogen (N2), helium (He), but is not limited to these.

[0079] As an example, in the present invention, the purge gas may be an inert gas, and the carrier gas or the diluent gas may be preferably used.

[0080] Then, a reaction gas is supplied. When the reaction gas is a reaction gas commonly used in the technical field to which the present invention belongs, there is no particular limitation, and preferably includes a reducing agent, a nitriding agent, or an oxidizing agent. The reducing agent reacts with the film precursor adsorbed on the substrate to form a metal film, the nitriding agent forms a metal nitride film, and the oxidizing agent forms a metal oxide film.

[0081] Preferably, the reducing agent may be ammonia (NH3) or hydrogen (H2), the nitriding agent may be nitrogen (N2), and the oxidizing agent may be one or more selected from H2O, H2O2, O2, O3 and N2O.

[0082] Then, the residual reaction gas that has not participated in the reaction is purged with an inert gas. In this way, not only the excess reaction gas but also the generated by-products can be removed.

[0083] As described above, a unit cycle includes the steps of adsorbing a thin film forming inhibitor on a substrate, purging unadsorbed thin film forming inhibitor, adsorbing a film precursor on a substrate, purging unadsorbed thin film forming composition, supplying a reaction gas, and purging residual reaction gas, and the unit cycle can be repeated to form a thin film having a desired thickness.

[0084] As an example, the unit cycle may be performed 100 to 1000 times, preferably 100 to 500 times, and more preferably 150 to 300 times. Within this range, the desired film characteristics are well expressed.

[0085] Figure 1 This is a process diagram for explaining the existing ALD process. Figure 2 1 is a process diagram for explaining an ALD process according to an embodiment of the present invention. Figure 1 When the thin film formation growth inhibitor of the present invention is not adsorbed before the film precursor (e.g., TiCl4) is adsorbed to protect the substrate surface as in the conventional ALD process, process byproducts such as HCl will remain in the thin film (e.g., TiN) formed by the reaction with the reaction gas (e.g., NH3), thereby reducing the performance of the substrate due to corrosion and degradation. Figure 2 As shown, when the thin film formation growth inhibitor (Inhibitor; TSI) of the present invention is adsorbed before the film precursor (e.g., TiCl4) is adsorbed to perform substrate surface protection (Surface Protection; SP), process byproducts such as HCl generated by reacting with the reaction gas (e.g., NH3) during the formation of the thin film (e.g., TiN) can be removed together with the thin film formation growth inhibitor, thereby preventing corrosion and degradation of the substrate, and then appropriately reducing the thin film growth rate per cycle, and improving the step coverage and uniformity of the film thickness.

[0086] The growth inhibitor for thin film formation of the present invention is preferably a compound represented by Chemical Formula 1,

[0087] Chemical formula 1:

[0088] A n B m X o

[0089] Wherein, A is carbon or silicon, B is hydrogen or an alkyl group having 1 to 3 carbon atoms, X is a halogen, n is an integer from 1 to 15, o is an integer greater than 1, and m is 0 to 2n+1. In this case, when a thin film is formed, the film growth rate is reduced by suppressing side reactions, and corrosion and degradation are reduced by removing process byproducts in the thin film, so that even when a thin film is formed on a substrate having a complex structure, the step coverage and the uniformity of the film thickness are greatly improved.

[0090] The B is preferably hydrogen or methyl, and the n is preferably an integer from 2 to 15, more preferably an integer from 2 to 10, more preferably an integer from 2 to 6, and further preferably an integer from 4 to 6. Within this range, the process by-product removal effect is good and the step coverage is excellent.

[0091] As an example, in the chemical formula 1, X may be one or more selected from F, Cl, Br and I, and may preferably be Cl (chlorine). In this case, side reactions are suppressed and process by-products are effectively removed.

[0092] In the chemical formula 1, the o may preferably be an integer from 1 to 5, more preferably an integer from 1 to 3, and even more preferably 1 or 2. Within this range, the deposition rate is effectively reduced, and therefore, it is more effective in improving the step coverage.

[0093] The m is preferably 1 to 2n+1, and more preferably 3 to 2n+1. Within this range, the process by-product removal effect is good and the step coverage is excellent.

[0094] The compound represented by the chemical formula 1 may preferably be a branched compound, a cyclic compound or an aromatic compound. As a specific embodiment, it is one or more selected from 1,1-dichloroethane, 1,2-dichloroethane, dichloromethane, 2-chloropropane, 1-chloropropane, 1,2-dichloropropane, 1,3-dichloropropane, 2,2-dichloropropane, 1-chloropentane, 2-chloropentane, 3-chloropentane, chlorocyclopentane, n-butyl chloride, tert-butyl chloride, sec-butyl chloride, isobutyl chloride, 1,2-dichlorobenzene, 1,4-dichlorobenzene, trimethylchlorosilane, trichloropropane, 2-chloro-2-methylbutane and 2-methyl-1-pentane. At this time, the advantage is that the process by-product removal effect is good and the step coverage is excellent.

[0095] The compound represented by Chemical Formula 1 is preferably used in an atomic layer deposition (ALD) process, in which case it has the advantages of not hindering the adsorption of film precursors, and at the same time, as a growth inhibitor, effectively protecting the surface of the substrate (Surface Protection; SP) and effectively removing process byproducts.

[0096] The compound represented by the chemical formula 1 may preferably be liquid at room temperature (22° C.) and have a density of 0.8 to 1.5 g / cm 3 , vapor pressure (20°C) is 1 to 300 mmHg, and solubility in water (25°C) is below 200 mg / L. Within this range, the step coverage and film thickness uniformity are excellent.

[0097] More preferably, the compound represented by the chemical formula 1 may have a density of 0.85 to 1.3 g / cm 3 , vapor pressure (20℃) is 1 to 260 mmHg, and solubility in water (25℃) is 160 mg / L. Within this range, the step coverage and film thickness uniformity are excellent.

[0098] The semiconductor substrate of the present invention is manufactured by the thin film manufacturing method of the present invention. In this case, the thin film growth rate is appropriately reduced by suppressing side reactions, and corrosion and degradation are prevented by removing process byproducts in the thin film, and the step coverage and thickness uniformity of the thin film are excellent.

[0099] Preferably, the thickness of the film manufactured above is less than 20nm, the resistivity value is 0.1 to 400μΩ·cm, the halogen content is less than 10,000ppm, and the step coverage is more than 90%. Within this range, it performs excellently as an anti-diffusion film and reduces corrosion of metal wiring materials, but is not limited to this.

[0100] As an example, the thickness of the film may be 5 to 20 nm, preferably 10 to 20 nm, more preferably 15 to 18.5 nm, and even more preferably 17 to 18.5 nm. Within this range, the film properties are excellent.

[0101] As an example, the resistivity value of the film can be 0.1 to 400 μΩ·cm, preferably 50 to 400 μΩ·cm, more preferably 200 to 400 μΩ·cm, even more preferably 300 to 400 μΩ·cm, further preferably 330 to 380 μΩ·cm, and most preferably 340 to 370 μΩ·cm. Within this range, the film properties are excellent.

[0102] The halogen content of the film may more preferably be 9,000 ppm or less or 1 to 9,000 ppm, further preferably 8,500 ppm or less or 100 to 8,500 ppm, further preferably 8,200 ppm or less or 1,000 to 8,200 ppm, within which range the film properties are excellent and corrosion of metal wiring materials is reduced.

[0103] As an example, the step coverage of the film is above 80%, preferably above 90%, and more preferably above 92%. Within this range, even a thin film with a complex structure can be easily deposited on the substrate, and thus can be applied to a new generation of semiconductor devices.

[0104] As an example, the manufactured thin film may be a metal nitride film or a metal oxide film, and as a specific example, it may be a TiN thin film or a TiO2 thin film.

[0105] Below, in order to help understand the present invention, preferred embodiments and drawings are proposed. However, it is clear to those skilled in the art that the following embodiments and drawings are only used to illustrate the present invention, and various changes and modifications can be made within the scope of the scope of the present invention and technical ideas, and such deformation and modification undoubtedly fall within the scope of the attached claims.

[0106] Example

[0107] Examples 1 to 7

[0108] Prepare the thin film formation growth inhibitor and TiCl4 as a film precursor recorded in Table 1 below respectively. The prepared thin film formation growth inhibitor is loaded into a tank and supplied to a vaporizer heated to 150°C at a flow rate of 0.05 g / min using a LMFC (Liquid Mass Flow Controller) at room temperature. After the thin film formation growth inhibitor vaporized into a vapor phase in the vaporizer is introduced into a deposition chamber loaded with a substrate for 3 seconds, argon gas is supplied at 3000 sccm for 6 seconds to purge with argon gas. At this time, the pressure in the reaction chamber is controlled to 1.3 Torr. Then, the prepared TiCl4 is loaded into another tank and supplied to another vaporizer heated to 150°C at a flow rate of 0.05 g / min using a LMFC (Liquid Mass Flow Controller) at room temperature. After TiCl4 vaporized in the vaporizer into a vapor phase is introduced into the deposition chamber for 3 seconds, argon gas is supplied at 3000 sccm for 6 seconds to purge with argon gas. At this time, the pressure in the reaction chamber is controlled to be 1.3 Torr. Then, ammonia gas is introduced into the reaction chamber as a reaction gas for 5 seconds, and then argon gas is purged for 10 seconds. At this time, the substrate on which the metal film is to be formed is heated to 460°C. This process is repeated 200 times to form a TiN film as a self-limiting atomic layer.

[0109] Table 1

[0110] category Growth inhibitors for thin film formation Example 1 2-chloro-2-methylbutane Example 2 n-butyl chloride Example 3 Trimethylchlorosilane Example 4 2-chloropropane Example 5 1,2,3-trichloropropane Example 6 2-methyl-1-pentane Example 7 1,2-dichlorobenzene

[0111] Comparative Example 1

[0112] A TiN thin film was formed on the substrate in the same manner as in Example 1, except that the thin film formation growth inhibitor of Example 1 was not used and thus the step of purging the unadsorbed thin film formation growth inhibitor was omitted.

[0113] Comparative Examples 2 and 3

[0114] A TiN thin film was formed on a substrate in the same manner as in Example 1, except that pentane or cyclopentane was used instead of the growth inhibitor for thin film formation in Example 1 described in Table 1.

[0115] Experimental example

[0116] 1) Deposition evaluation

[0117] Referring to Table 2 below, Example 1 in which 2-chloro-2-methylbutane was used as a growth inhibitor for thin film formation was compared with Comparative Example 1 which did not contain it. As a result, the deposition rate was The deposition rate was reduced by more than 55.5% compared to Comparative Example 1. It was confirmed that the remaining Examples 2 to 7 also had deposition rates similar to that of Example 1. In addition, it was confirmed that Comparative Examples 2 and 3, which did not use the growth inhibitor for thin film formation of the present invention but used pentane or cyclopentane, also had the same deposition rate as Comparative Example 1. In this case, the reduction in deposition rate indicates that the CVD deposition characteristics are changed to the ALD deposition characteristics, and thus can be used as an indicator of improvement in step coverage characteristics.

[0118] Table 2

[0119]

[0120] In addition, as shown in Table 3 below, it can be confirmed that the deposition rate continues to decrease as the injection amount of 2-chloro-2-methylbutane as a growth inhibitor for thin film formation increases. Example 1-1 was carried out in the same manner as Example 1 except for the injection amount of the growth inhibitor for thin film formation per cycle.

[0121] Table 3

[0122]

[0123] 2) Impurity reduction characteristics

[0124] In order to compare the impurity reduction characteristics, that is, the process by-product reduction characteristics, of the TiN films deposited in Example 1 and Comparative Example 1, SIMS analysis was performed, and the results are shown in Table 4 below.

[0125] Table 4

[0126] category Example 1 Comparative Example 1 Injection amount per ALD cycle (mg / cycle) 1.6 0 Cl intensity (c / s) 5907.05 17270.25

[0127] As shown in Table 4, it can be confirmed that the Cl intensity of Example 1 using the growth inhibitor for thin film formation of the present invention is reduced to 1 / 3 of that of Comparative Example 1 not using the growth inhibitor for thin film formation of the present invention.

[0128] in addition, Figure 3 This is a graph showing the change in film thickness of Example 7 (SP-TiCl4) of the present invention and Comparative Example 1 (TiCl4) as the ALD cycle increases. It can be confirmed that the thickness of the film of Example 7 is significantly thinned.

[0129] in addition, Figure 4 : is a graph showing the deposition rate of Examples 7-1 to 7-3 of the present invention and Comparative Example 1 as a function of the feeding time of the growth inhibitor (SP) for thin film formation per ALD cycle. It can be determined that when the thin film formation inhibitor of the present invention is not used as in Comparative Example 1, the deposition rate per cycle is approximately In the case of Examples 7-1, 7-2, and 7-3, in which the inhibitor for thin film formation of the present invention was added for 0.7 seconds, 1 second, and 2 seconds, respectively, the deposition rate was significantly reduced to However, Examples 7-1, 7-2, and 7-3 were carried out in the same manner as in Example 7 except for the amount of the growth inhibitor for thin film formation added.

[0130] 3) Step coverage characteristics

[0131] The step coverage of the TiN films deposited in Example 1 and Comparative Example 1 was determined using TEM. The results are shown in Tables 5 and Figure 5 .

[0132] Table 5

[0133] category Example 1 Comparative Example 1 Ladder coverage rate (%) 92％ 78％

[0134] As shown in Table 5, it can be confirmed that Example 1 using the growth inhibitor for thin film formation of the present invention has a significantly higher step coverage than Comparative Example 1 not using the growth inhibitor for thin film formation of the present invention. Figure 5 From the TEM images, it can be determined that the thickness uniformity of the top and bottom of the TiN film deposited in Example 1 (SP-TiCl4) is better than that of the TiN film deposited in Comparative Example 1 (TiCl4), and the step coverage (conformality) is better.

[0135] Additional Example 1

[0136] The process is carried out in the same manner as in the above-mentioned Example 1, except that tris(dimethylamino)cyclopentadienylzirconium (CpZr) is used instead of TiCl4 as a film precursor in the above-mentioned Example 1, the injection amount of the growth inhibitor for thin film formation into the chamber is set to 12 mg / sec, ozone is used instead of ammonia as a reaction gas, and the substrate on which the metal thin film is to be formed is heated to 280 to 340°C. To form a zirconium oxide film (ZrO2 thin film).

[0137] Additional Example 2

[0138] The process is carried out in the same manner as in Additional Example 1, thereby forming a zirconium oxide film (ZrO2 thin film), except that the injection amount of the growth inhibitor for thin film formation in Additional Example 1 is set to 2.3 mg / sec and is injected for 1 to 7 seconds respectively and the substrate on which the metal thin film is to be formed is heated to 310°C.

[0139] Additional Comparative Example 1

[0140] A zirconium oxide film (ZrO 2 thin film) was formed by performing the same process as in the above-mentioned Additional Example 1 except that the growth inhibitor for thin film formation was not used in the above-mentioned Additional Example 1.

[0141] The deposition rate, reduction rate (%) and thickness uniformity (%) of the zirconium oxide film deposited in the above-mentioned additional examples 1 and 2 and the additional comparative example 1 were measured, and the results are shown in the following Tables 6 and Figure 6 At this time, the thickness uniformity (%) is calculated by Mathematical Formula 2.

[0142] Mathematical formula 2:

[0143] Thickness uniformity (%) = [(MAX-MIN) / (2×AVERAGE)]×100%

[0144] The MAX, MIN, and AVERAGE represent the maximum value, minimum value, and average value of thickness, and each thickness is an optical thickness measured by an ellipsometer.

[0145] Table 6

[0146]

[0147]

[0148] As shown in Table 6 above, the thickness of the zirconium oxide film formed using the growth inhibitor for thin film formation of the present invention (Example 1) is 0.508 to 1.000 mm / s per ALD cycle, compared with the zirconium oxide film formed without the growth inhibitor for thin film formation of the present invention (Comparative Example 1). It is very constant, while the reduction rate is greatly reduced to the range of 34.6% to 42.3%, and the uniformity of film thickness is in the range of 1.1% to 2.1%, with very small fluctuation range.

[0149] in addition, Figure 6 The deposition rates of Example 2 and Comparative Example 1 are shown. From the graph of the feeding time (s) of the growth inhibitor for thin film formation (SP) per ALD cycle, it can be confirmed that when the growth inhibitor for thin film formation of the present invention is not used as in Comparative Example 1, the deposition rate per cycle is about In the case of Example 2 in which the inhibitor for thin film formation of the present invention was added for 1 second, 3 seconds, 5 seconds, and 7 seconds, respectively, the deposition rate was reduced to about Among them, SP-P-SF-P-OF-P represents the introduction of a growth inhibitor (SP) for thin film formation, the introduction of a purge gas (P), the introduction of a film precursor (SF), the introduction of a purge gas (P), the introduction of a reaction gas (OF), and the introduction of a purge gas (P) in one cycle, X-2X-5-10-3-6 represents the input time (s) of each step, and X is an integer from 0 to 7.

Claims

1. A method for producing a thin film, characterized in that: include: Step (i), allowing a growth inhibitor for thin film formation to be adsorbed on the surface of the substrate; as well as Step (ii), adsorbing a metal film precursor, a metal oxide film precursor, a metal nitride film precursor or a silicon nitride film precursor onto the surface of the substrate adsorbed with a growth inhibitor for thin film formation, The growth inhibitor for thin film formation is represented by Chemical Formula 1: The metal is one or more selected from tungsten, cobalt, chromium, aluminum, hafnium, vanadium, niobium, germanium, lanthanides, actinides, gallium, tantalum, zirconium, ruthenium, copper, titanium, nickel, iridium and molybdenum, Chemical formula 1: A n B m X o Wherein, A is carbon or silicon, B is hydrogen or an alkyl group having 1 to 3 carbon atoms, X is a halogen, n is an integer from 1 to 15, o is an integer greater than 1, and m is 0 to 2n+1.

2. The thin film manufacturing method according to claim 1, characterized in that: In the step (i) of allowing the growth inhibitor for thin film formation to be adsorbed on the surface of the substrate, the growth inhibitor for thin film formation is supplied to the surface of the substrate for a period of 1 to 10 seconds.

3. The thin film manufacturing method according to claim 1, characterized in that: In the step (i) of allowing the growth inhibitor for thin film formation to be adsorbed on the surface of the substrate, the growth inhibitor for thin film formation is injected into an ALD (atomic layer deposition) chamber and allowed to be adsorbed on the surface of the loaded substrate.

4. The thin film manufacturing method according to claim 1, characterized in that: In the step (i) of allowing the growth inhibitor for thin film formation to be adsorbed on the surface of the substrate, the residual growth inhibitor for thin film formation that is not adsorbed on the surface of the substrate is purged using a purge gas.

5. The thin film manufacturing method according to claim 1, characterized in that: In the step (ii) of adsorbing the membrane precursor, the residual membrane precursor that is not adsorbed is purged using a purge gas.

6. The thin film manufacturing method according to claim 1, characterized in that: The steps include: After the film precursor is adsorbed on the surface of the substrate, a reaction gas is supplied; and The reaction byproducts of the film precursor and the reaction gas are purged using a purge gas.

7. The thin film manufacturing method according to claim 6, characterized in that: The reaction gas is a reducing agent, a nitriding agent or an oxidizing agent.

8. The thin film manufacturing method according to claim 1, characterized in that: The thin film formation growth inhibitor and the film precursor are transferred to the substrate surface by a VFC method, a DLI method, or an LDS method.

9. The thin film manufacturing method according to claim 1, characterized in that: The ratio of the amount (mg / cycle) of the growth inhibitor for thin film formation to the amount (mg / cycle) of the film precursor added to the substrate surface is 1:1.5 to 1:

20.

10. The thin film manufacturing method according to claim 1, characterized in that: In the chemical formula 1, X is chlorine (Cl).

11. The thin film manufacturing method according to claim 1, characterized in that: In the chemical formula 1, o is an integer of 1 to 5.

12. The thin film manufacturing method according to claim 1, characterized in that: The compound represented by the chemical formula 1 is a branched compound, a cyclic compound or an aromatic compound.

13. The thin film manufacturing method according to claim 1, characterized in that: The compound represented by the chemical formula 1 is liquid at room temperature 22°C and has a density of 0.8 to 1.5 g / cm 3 The vapor pressure at 20°C is 1 to 300 mmHg, and the solubility in water at 25°C is less than 200 mg / L.

14. The thin film manufacturing method according to claim 1, characterized in that: The film growth rate per cycle is calculated by the following mathematical formula 1: The reduction rate is less than -5%, Mathematical formula 1: Reduction rate of film growth rate per cycle (%) = [(film growth rate per cycle when using growth inhibitor for film formation - film growth rate per cycle when not using growth inhibitor for film formation) / film growth rate per cycle when not using growth inhibitor for film formation] × 100.

15. The thin film manufacturing method according to claim 1, characterized in that: The residual halogen intensity (c / s) in the film formed after 200 cycles measured by SIMS was 10,000 or less.

16. A thin film manufacturing device, characterized in that: include: ALD (atomic layer deposition) chamber; a first vaporizer for vaporizing a growth inhibitor for thin film formation; A first transfer unit transfers the vaporized growth inhibitor for thin film formation into the ALD chamber; a second vaporizer for vaporizing a metal film precursor, a metal oxide film precursor, a metal nitride film precursor, or a silicon nitride film precursor; as well as The second transfer unit transfers the vaporized precursor into the ALD chamber.

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