Shield compound, thin film forming method using same, semiconductor substrate manufactured thereby

Abstract

The present invention relates to a shielding compound, a method for forming a thin film using the same, a semiconductor substrate manufactured thereby, and a semiconductor device, and provides a compound having a predetermined structure as a shielding compound to form a shielding region for a silicon-based thin film on a substrate so as to reduce the deposition rate of the silicon-based thin film and appropriately reduce the growth rate of the thin film. Thus, even if a thin film is formed on a substrate having a complicated structure, it is possible to greatly improve step coverage and thickness uniformity of the thin film, reduce corrosion and deterioration, and improve crystallinity of the thin film, thereby improving electrical characteristics of the thin film.

Description

Technical Field

[0001] The present invention relates to a masking compound, a method for forming a thin film using the same, a semiconductor substrate manufactured thereby, and a semiconductor device. Specifically, a masking region for forming a silicon-based thin film is formed on a substrate to reduce the deposition rate of the silicon-based thin film and appropriately reduce the film growth rate, so that even when forming a thin film on a substrate with a complex structure, the step coverage and the thickness uniformity of the thin film can be significantly improved. A masking compound, a method for forming a thin film using the same, and a semiconductor substrate manufactured thereby. Background Art

[0002] The integration degree of memory and non-memory semiconductor devices is increasing day by day. As their structures gradually become complex, the importance of step coverage is gradually increasing when depositing various thin films on a substrate.

[0003] The above-mentioned semiconductor thin films are formed of a nitride film, an oxide film, a metal film, etc. The above-mentioned nitride films include silicon nitride (SiN), titanium nitride (TiN), tantalum nitride (TaN), etc. The above-mentioned oxide films include silicon oxide (SiO 2 ), hafnium oxide (HfO 2 ), zirconium oxide (ZrO 2 ), etc. The above-mentioned metal films include molybdenum (Mo) film, tungsten (W) film, ruthenium (Ru) film, etc.

[0004] The above-mentioned thin films are usually used as a diffusion barrier between a silicon layer of a doped semiconductor and aluminum (Al), copper (Cu), etc. used as an interlayer wiring material. Only when depositing a tungsten (W) thin film 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, high step coverage of the formed thin film is essential. Therefore, the atomic layer deposition (ALD) process using surface reaction is used instead of the chemical vapor deposition (CVD) process mainly using gas-phase reaction, but it is still difficult to achieve 100% step coverage.

[0006] In addition, as a method for improving step coverage, a method of reducing the growth rate of the thin film has been proposed. However, the problem is that when the deposition temperature is reduced to reduce the growth rate of the thin film, the residual amount of impurities such as carbon or chlorine in the thin film increases, resulting in a significant reduction in film quality.

[0007] In addition, process by-products such as chlorides remain in the produced thin film, inducing corrosion of metals such as aluminum, and the formation of non-volatile by-products causes deterioration of the film quality.

[0008] Therefore, it is necessary to develop a method for forming a thin film that can form a thin film with a complex structure, has a low residual amount of impurities, and significantly improves step coverage and thickness uniformity of the thin film, as well as a semiconductor substrate manufactured thereby.

[0009] [Prior Art Documents]

[0010] [Patent Documents]

[0011] Korean Patent Publication No. 2011-0048195 Summary of the Invention

[0012] Problems to be Solved by the Invention

[0013] The present invention aims to solve the problems in the prior art as described above, and an object thereof is to provide a masking compound, a thin film forming method using the same, and a semiconductor substrate manufactured thereby, which form a masking region for a silicon-based thin film on a substrate to reduce the deposition rate of the silicon-based thin film and appropriately reduce the film growth rate, so that even when forming a thin film on a substrate with a complex structure, the step coverage and thickness uniformity of the thin film can be significantly improved.

[0014] Another object of the present invention is to improve the crystallinity of the thin film to improve the density and electrical properties of the thin film.

[0015] The above object and other multiple objects of the present invention can be fully achieved by the present invention described below.

[0016] Means for Solving the Problems

[0017] To achieve the above object, the present invention provides a masking compound for a silicon-based thin film, wherein the silicon-based thin film has a film composition of SixNy (x and y are positive numbers of 0.5 to 4.5 respectively),

[0018] The masking compound is a saturated compound represented by Chemical Formula 1,

[0019] [Chemical Formula 1]

[0020]

[0021] (In the formula, A is carbon,

[0022] R 1 、R 3 are independently alkyl groups having 1 to 6 carbon atoms,

[0023] R2 Independently an alkyl group having 1 to 6 carbon atoms or having a functional group of the formula BR 4 R 5 R 6 wherein B is a carbon bonded to A above, and the above R 4 、R 5 and R 6 are independently hydrogen, an alkyl group having 1 to 6 carbon atoms, fluorine (F), chlorine (Cl), bromine (Br), or iodine (I),

[0024] The above X is a halogen element, which is fluorine (F), chlorine (Cl), bromine (Br), or iodine (I).

[0025] The refractive index (a) of the above masking compound can be in the range of 1.38 to 1.52. At the same time, the vapor pressure (mmHg, b) at 25 °C divided by the value of the above refractive index (a) (b / a) can be in the range of 0.003 to 0.033.

[0026] The above silicon-based thin film can be formed of Si 3 N 4 、Si 2 N 3 、Si 2 N, SiN, or a mixture thereof.

[0027] The above masking compound can provide a masking area for the silicon-based thin film.

[0028] The above masking area for the silicon-based thin film does not remain on the above silicon-based thin film, and the content of the halogen element in the above silicon-based thin film can be less than 0.01% by weight.

[0029] The above silicon-based thin film can be used as an anti-diffusion film, an etch stop film, or a charge trap.

[0030] In addition, the present invention provides a method for forming a silicon-based thin film, which includes the following steps:

[0031] Inject a masking compound having a saturated structure represented by Chemical Formula 1 into the chamber to mask the surface of the loaded substrate.

[0032] [Chemical Formula 1]

[0033]

[0034] (wherein A above is carbon,

[0035] the above R 1 、R 3 are independently alkyl groups having 1 to 6 carbon atoms,

[0036] the above R 2Independently an alkyl group having 1 to 6 carbon atoms or a functional group having the formula BR 4 R 5 R 6 wherein B is a carbon atom bonded to A, and the above R 4 、R 5 and R 6 are independently hydrogen, an alkyl group having 1 to 6 carbon atoms, fluorine (F), chlorine (Cl), bromine (Br), or iodine (I).

[0037] The above X is a halogen element, which is fluorine (F), chlorine (Cl), bromine (Br), or iodine (I).)

[0038] A method for forming a silicon-based thin film may include the following steps:

[0039] A masking area forming step of vaporizing a masking compound to form a masking area on the surface of a substrate loaded in a chamber;

[0040] A first purging step of purging the inside of the above chamber with a purge gas for the first time;

[0041] An adsorption step of vaporizing a precursor compound and adsorbing it to an area that has escaped from the above masking area;

[0042] A second purging step of purging the inside of the above chamber with a purge gas for the second time;

[0043] A reaction gas supply step of supplying a reaction gas to the inside of the above chamber; and

[0044] A third purging step of purging the inside of the above chamber with a purge gas for the third time.

[0045] A method for forming a silicon-based thin film may include the following steps:

[0046] An adsorption step of vaporizing a precursor compound and adsorbing it to the surface of a substrate loaded in a chamber;

[0047] A first purging step of purging the inside of the above chamber with a purge gas for the first time;

[0048] A masking step of vaporizing a masking compound to mask the surface of a substrate loaded in a chamber;

[0049] A second purging step of purging the inside of the above chamber with a purge gas for the second time;

[0050] A reaction gas supply step of supplying a reaction gas to the inside of the above chamber; and

[0051] A third purging step of purging the inside of the above chamber with a purge gas for the third time.

[0052] As an example, the above-mentioned precursor compound may be a molecule composed of Si and one or more selected from C, N, H, and Cl. Preferably, it may be a molecule composed of Si, H, and Cl. At this time, the deposition rate can be reduced, and the content of halogen elements in the silicon-based thin film is less than 0.01%.

[0053] The above-mentioned precursor compound may be a silicon precursor having a vapor pressure of 2 mTorr to 75 KTorr at 25 °C.

[0054] The above-mentioned chamber may be an atomic layer deposition (ALD) chamber or a chemical vapor deposition (CVD) chamber.

[0055] The method for forming a silicon-based thin film may include the following steps: a post-treatment step of performing plasma post-treatment after vaporizing and injecting the above-mentioned masking compound or precursor compound.

[0056] The amount of purge gas introduced into the chamber during the above-mentioned first purge step and the above-mentioned second purge step may be 10 to 100,000 times the volume of the masking compound introduced.

[0057] The above-mentioned reaction gas may be a nitriding agent, and the above-mentioned reaction gas, masking compound, and precursor compound may be delivered into the chamber by a vapor flow control (VFC) method, a direct liquid injection (DLI) method, or a liquid delivery system (LDS) method.

[0058] The substrate loaded in the chamber may be heated to 300 to 800 °C. As a specific example, it may be heated to 500 to 700 °C.

[0059] The ratio of the amount of the above-mentioned masking compound to the amount of the above-mentioned precursor compound introduced into the chamber (mg / cycle) may be 1:1.5 to 1:20. As a specific example, it may be 1:3 to 1:15.

[0060] In addition, the present invention provides a semiconductor substrate manufactured by the above-mentioned method for forming a silicon-based thin film.

[0061] The above-mentioned silicon-based thin film may have a multi-layer structure of two or three layers.

[0062] The above-mentioned silicon-based thin film may be a Si-rich thin film, or a part of a Si-rich thin film or an N-rich thin film.

[0063] In addition, the present invention provides a semiconductor device including the above-mentioned semiconductor substrate.

[0064] The semiconductor substrate described above may be low resistive metal gate interconnects, a high aspect ratio 3D metal-insulator-metal capacitor, a DRAM trench capacitor, 3D Gate-All-Around (GAA), or 3D NAND.

[0065] Advantages of the Invention

[0066] According to the present invention, it is possible to provide a masking compound that can form a masking region for a silicon-based thin film on a substrate to reduce the deposition rate of the silicon-based thin film and appropriately reduce the film growth rate, so that even when forming a thin film on a substrate with a complex structure, the step coverage can be improved.

[0067] In addition, when forming a thin film, process by-products can be more effectively reduced to prevent corrosion and deterioration, and the crystallinity of the thin film can be improved, thereby improving the electrical properties of the thin film.

[0068] In addition, it is possible to reduce process by-products when forming a thin film, improve step coverage and film density, and further provide a thin film forming method using the same and a semiconductor substrate manufactured thereby. Description of the Drawings

[0069] Figure 1 It is a SIMS analysis curve graph of the SiN thin film manufactured in Example 1 using the masking compound used in the present invention and Comparative Example 1 without using the masking compound used in the present invention.

[0070] Figure 2 It is a curve graph for observing the change in the deposition rate of the masking compound used in the present invention at different supply times.

[0071] Figure 3 It is a curve graph showing the results of analyzing elements at different depths by Ar sputtering for the SiN thin films manufactured in Examples 3 to 4 and Comparative Example 4.

[0072] Figure 4 It is a SIMS analysis curve graph of the SiN thin film manufactured in Example 3 and Comparative Example 4.

[0073] Figure 5 It is a TEM photograph for confirming the step coverage of the SiN thin film deposited on a trench substrate with an aspect ratio of 23:1 in Examples 3 to 4 and Comparative Example 4. Detailed Description

[0074] Hereinafter, a masking compound for a silicon-based thin film, a method for forming a silicon-based thin film using the same, and a semiconductor substrate manufactured thereby will be described in detail.

[0075] Unless otherwise defined, the term "masking" used in the present invention not only means reducing, preventing, or blocking the adsorption of a precursor compound for forming a silicon-based thin film onto a substrate, but also means reducing, preventing, or blocking the adsorption of process by-products onto the substrate.

[0076] Unless otherwise defined, the term "a part of an area" or "a part of a substrate" in the present invention refers to a specific layer portion based on the horizontal surface of the substrate or a specific layer portion based on the vertical surface of the substrate.

[0077] The inventors of the present invention confirmed that when using a masking compound for masking a precursor compound (for forming a silicon-based thin film on the surface of a substrate loaded inside a chamber), while forming a masking region that does not remain in the silicon-based thin film at a reduced deposition rate, the film growth rate is significantly reduced. Therefore, even when applied to a substrate with a complex structure, film uniformity can be ensured, thereby significantly improving step coverage. In particular, it is possible to deposit with a thin thickness and improve the residual amount of halides remaining as process by-products and the amount of residual carbon that is difficult to reduce even when using an excessive amount of reducing gas. Based on this, research was conducted on a masking compound that provides a masking region, and the present invention was completed.

[0078] The masking compound of the present invention provides a masking compound for a silicon-based thin film.

[0079] As an example, the above silicon-based thin film may be formed from a material selected from SiH 4 , SiCl 4 , SiF 4 , SiCl 2 H 2 , Si 2 Cl 6 , TEOS, DIPAS, BTBAS, (NH 2 )Si(NHMe) 3 , (NH 2 )Si(NHEt) 3 , (NH 2 )Si(NH n Pr) 3 , (NH 2 )Si(NH i Pr) 3 , (NH 2 )Si(NH n Bu) 3 , (NH 2 )Si(NHi Bu) 3 、(NH 2 )Si(NH t Bu) 3 、(NMe 2 )Si(NHMe) 3 、(NMe 2 )Si(NHEt) 3 、(NMe 2 )Si(NH n Pr) 3 、(NMe 2 )Si(NH i Pr) 3 、(NMe 2 )Si(NH n Bu) 3 、(NMe 2 )Si(NH i Bu) 3 、(NMe 2 )Si(NH t Bu) 3 、(NEt 2 )Si(NHMe) 3 、(NEt 2 )Si(NHEt) 3 、(NEt 2 )Si(NH n Pr) 3 、(NEt 2 )Si(NH i Pr) 3 、(NEt 2 )Si(NH n Bu) 3 、(NEt 2 )Si(NH i Bu) 3 、(NEt 2 )Si(NH t Bu) 3 、(N n Pr 2 )Si(NHMe) 3 、(N n Pr 2 )Si(NHEt) 3 、(N n Pr 2 )Si(NH n Pr) 3 、(N n Pr 2 )Si(NH i )Si(NH3 , (N n Pr 2 )Si(NH n Bu) 3 , (N n Pr 2 )Si(NH i Bu) 3 , (N n Pr 2 )Si(NH t Bu) 3 , (N i Pr 2 )Si(NHMe) 3 , (N i Pr 2 )Si(NHEt) 3 , (N i Pr 2 )Si(NH n Pr) 3 , (N i Pr 2 )Si(NH i Pr) 3 , (N i Pr 2 )Si(NH n Bu) 3 , (N i Pr 2 )Si(NH i Bu) 3 , (N i Pr 2 )Si(NH t Bu) 3 , (N n Bu 2 )Si(NHMe) 3 , (N n Bu 2 )Si(NHEt) 3 , (N n Bu 2 )Si(NH n Pr) 3 , (N n Bu 2 )Si(NH i Pr) 3 , (N n Bu 2 )Si(NH n Bu) 3 , (N n Bu 2 )Si(NH iBu) 3 、(N n Bu 2 )Si(NH t Bu) 3 、(N i Bu 2 )Si(NHMe) 3 、(N i Bu 2 )Si(NHEt) 3 、(N i Bu 2 )Si(NH n Pr) 3 、(N i Bu 2 )Si(NH i Pr) 3 、(N i Bu 2 )Si(NH n Bu) 3 、(N i Bu 2 )Si(NH i Bu) 3 、(N i Bu 2 )Si(NH t Bu) 3 、(N t Bu 2 )Si(NHMe) 3 、(N t Bu 2 )Si(NHEt) 3 、(N t Bu 2 )Si(NH n Pr) 3 、(N t Bu 2 )Si(NH i Pr) 3 、(N t Bu 2 )Si(NH n Bu) 3 、(N t Bu 2 )Si(NH i Bu) 3 、(N t Bu 2 )Si(NH t Bu) 3 、(NH 2 ) 2 Si(NHMe)2 、(NH 2 ) 2 Si(NHEt) 2 、(NH 2 ) 2 Si(NH n Pr) 2 、(NH 2 ) 2 Si(NH i Pr) 2 、(NH 2 ) 2 Si(NH n Bu) 2 、(NH 2 ) 2 Si(NH i Bu) 2 、(NH 2 ) 2 Si(NH t Bu) 2 、(NMe 2 ) 2 Si(NHMe) 2 、(NMe 2 ) 2 Si(NHEt) 2 、(NMe 2 ) 2 Si(NH n Pr) 2 、(NMe 2 ) 2 Si(NH i Pr) 2 、(NMe 2 ) 2 Si(NH n Bu) 2 、(NMe 2 ) 2 Si(NH i Bu) 2 、(NMe 2 ) 2 Si(NH t Bu) 2 、(NEt 2 ) 2 Si(NHMe) 2 、(NEt 2 ) 2 Si(NHEt) 2 、(NEt 2 ) 2 Si(NH n Pr) 2 、(NEt2 ) 2 Si(NH i Pr) 2 、(NEt 2 ) 2 Si(NH n Bu) 2 、(NEt 2 ) 2 Si(NH i Bu) 2 、(NEt 2 ) 2 Si(NH t Bu) 2 、(N n Pr 2 ) 2 Si(NHMe) 2 、(N n Pr 2 ) 2 Si(NHEt) 2 、(N n Pr 2 ) 2 Si(NH n Pr) 2 、(N n Pr 2 ) 2 Si(NH i Pr) 2 、(N n Pr 2 ) 2 Si(NH n Bu) 2 、(N n Pr 2 ) 2 Si(NH i Bu) 2 、(N n Pr 2 ) 2 Si(NH t Bu) 2 、(N i Pr 2 ) 2 Si(NHMe) 2 、(N i Pr 2 ) 2 Si(NHEt) 2 、(N i Pr 2 ) 2 Si(NH n Pr) 2 、(Ni Pr 2 ) 2 Si(NH i Pr) 2 、(N i Pr 2 ) 2 Si(NH n Bu) 2 、(N i Pr 2 ) 2 Si(NH i Bu) 2 、(N i Pr 2 ) 2 Si(NH t Bu) 2 、(N n Bu 2 ) 2 Si(NHMe) 2 、(N n Bu 2 ) 2 Si(NHEt) 2 、(N n Bu 2 ) 2 Si(NH n Pr) 2 、(N n Bu 2 ) 2 Si(NH i Pr) 2 、(N n Bu 2 ) 2 Si(NH n Bu) 2 、(N n Bu 2 ) 2 Si(NH i Bu) 2 、(N n Bu 2 ) 2 Si(NH t Bu) 2 、(N i Bu 2 ) 2 Si(NHMe) 2 、(N i Bu 2 ) 2 Si(NHEt) 2 、(N i Bu 2) 2 Si(NH n Pr) 2 、(N i Bu 2 ) 2 Si(NH i Pr) 2 、(N i Bu 2 ) 2 Si(NH n Bu) 2 、(N i Bu 2 ) 2 Si(NH i Bu) 2 、(N i Bu 2 ) 2 Si(NH t Bu) 2 、(N t Bu 2 ) 2 Si(NHMe) 2 、(N t Bu 2 ) 2 Si(NHEt) 2 、(N t Bu 2 ) 2 Si(NH n Pr) 2 、(N t Bu 2 ) 2 Si(NH i Pr) 2 、(N t Bu 2 ) 2 Si(NH n Bu) 2 、(N t Bu 2 ) 2 Si(NH i Bu) 2 、(N t Bu 2 ) 2 Si(NH t Bu) 2 、Si(HNCH 2 CH 2 NH) 2 、Si(MeNCH 2 CH 2 NMe) 2, Si(EtNCH 2 CH 2 NEt) 2 , Si( n PrNCH 2 CH 2 N n Pr) 2 , Si( i PrNCH 2 CH 2 N i Pr) 2 , Si( n BuNCH 2 CH 2 N n Bu) 2 , Si( i BuNCH 2 CH 2 N i Bu) 2 , Si( t BuNCH 2 CH 2 N 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 BuNCHCHN n Bu) 2 , Si( i BuNCHCHN i Bu) 2 , Si( t BuNCHCHN t Bu) 2 , (HNCHCHNH)Si(HNCH 2 CH 2 NH), (MeNCHCHNMe)Si(MeNCH 2 CH 2 NMe), (EtNCHCHNEt)Si(EtNCH 2 CH 2 NEt), ( n PrNCHCHN nPr)Si( n PrNCH 2 CH 2 N n Pr)、( i PrNCHCHN i Pr)Si( i PrNCH 2 CH 2 N i Pr)、( n BuNCHCHN n Bu)Si( n BuNCH 2 CH 2 N n Bu)、( i BuNCHCHN i Bu)Si( i BuNCH 2 CH 2 N i Bu)、( t BuNCHCHN t Bu)Si( t BuNCH 2 CH 2 N t Bu)、(NH t Bu) 2 Si(HNCH 2 CH 2 NH)、(NH t Bu) 2 Si(MeNCH 2 CH 2 NMe)、(NH t Bu) 2 Si(EtNCH 2 CH 2 NEt)、(NH t Bu) 2 Si( n PrNCH 2 CH 2 N n Pr)、(NH t Bu) 2 Si( i PrNCH 2 CH 2 N i Pr)、(NH t Bu) 2 Si( n BuNCH 2 CH 2 N nBu), (NH t Bu) 2 Si( i BuNCH 2 CH 2 N i Bu), (NH t Bu) 2 Si( t BuNCH 2 CH 2 N t Bu), (NH t Bu) 2 Si(HNCHCHNH), (NH t Bu) 2 Si(MeNCHCHNMe), (NH t Bu) 2 Si(EtNCHCHNEt), (NH t Bu) 2 Si( n PrNCHCHN n Pr), (NH t Bu) 2 Si( i PrNCHCHN i Pr), (NH t Bu) 2 Si( n BuNCHCHN n Bu), (NH t Bu) 2 Si( i BuNCHCHN i Bu), (NH t Bu) 2 Si( t BuNCHCHN t Bu), ( i PrNCH 2 CH 2 N i Pr)Si(NHMe) 2 , ( i PrNCH 2 CH 2 N i Pr)Si(NHEt) 2 , ( i PrNCH 2 CH 2 N i Pr)Si(NH n Pr) 2 , ( i PrNCH2 CH 2 N i Pr)Si(NH i Pr) 2 、( i PcqI 2 CH 2 N i Pr)Si(NH n Bu) 2 、( i PcqI 2 CH 2 N i Pr)Si(NH i Bu) 2 、( i PcqI 2 CH 2 N i Pr)Si(NH t Bu) 2 、( i PnCH i Pr)Si(NHMe) 2 、( i PnCH i Pr)Si(NHEt) 2 、( i PnCH i Pr)Si(NH n Pr) 2 、( i PnCH i Pr)Si(NH i Pr) 2 、( i PnCH i Pr)Si(NH n Bu) 2 、( i PnCH i Pr)Si(NH i Bu) 2 as well as( i PnCH i Pr)Si(NH t Bu) 2 In this case, the desired effect of the present invention can be fully achieved.

[0080] Above n Pr represents n-propyl, i Pr represents isopropyl, n Bu represents n-butyl, iBu represents isobutyl, t Bu represents tert-butyl.

[0081] As a specific example, the above-mentioned silicon-based thin film may have Si x N y as a film component.

[0082] Among them, x and y can be positive numbers in the range of 0.5 to 4.5, respectively.

[0083] Preferably, the above-mentioned x and y can be positive numbers in the range of 2.5 to 4.5, respectively.

[0084] The above-mentioned silicon-based thin film can be formed of Si 3 N 4 , Si 2 N 3 , Si 2 N, SiN or their mixtures, but not limited thereto, and may also include SiH and SiOH.

[0085] The above-mentioned silicon-based thin film can be used not only as a diffusion barrier film commonly used in semiconductor devices, but also as an etch stop film or a charge trap.

[0086] The above-mentioned masking compound is a saturated compound represented by Chemical Formula 1. At this time, it is possible to form a masking region that will not remain in the silicon-based thin film at a reduced deposition rate while suppressing side reactions when forming the silicon-based thin film, and adjust the film growth rate to reduce process by-products in the film, thereby reducing corrosion and deterioration, and improving the crystallinity of the film. Even when forming a film on a substrate with a complex structure, it is possible to significantly improve the step coverage and the thickness uniformity of the film.

[0087] [Chemical Formula 1]

[0088]

[0089] (In the above, A is carbon,

[0090] In the above, R 1 , R 3 are independently alkyl groups having 1 to 6 carbon atoms,

[0091] In the above, R 2 is independently an alkyl group having 1 to 6 carbon atoms or a functional group having the formula BR 4 R 5 R 6 . In the above, B is carbon bonded to the above A, and the above R 4 , R 5 and R 6 are independently hydrogen, an alkyl group having 1 to 6 carbon atoms, fluorine (F), chlorine (Cl), bromine (Br) or iodine (I),

[0092] The above X is fluorine (F), chlorine (Cl), bromine (Br) or iodine (I) which are halogen elements.)

[0093] In the above Chemical Formula 1, the above A is carbon.)

[0094] The above R 1 , R 2 and R 3 are each independently an alkyl group having 1 to 6 carbon atoms, and at least one of them has 2 to 5 carbon atoms. As a preferred example, any one of the above R 1 , R 2 and R 3 has 1 carbon atom, and the other two have 2 or 3 carbon atoms. More preferably, any one of the above R 1 , R 2 and R 3 has 1 carbon atom, and the other two have 2 carbon atoms. Within this range, it has the advantages of significantly reducing process by-products, excellent step coverage, and more excellent film density improvement effect and electrical properties of the film.)

[0095] In the above Chemical Formula 1, X is a halogen element, preferably fluorine, chlorine or bromine, more preferably chlorine or bromine. Within this range, it has the advantages of more excellent reduction of process by-products and improvement of step coverage. Additionally, as an example, the above X can be fluorine, and in this case, it has the advantage of being more suitable for processes requiring high-temperature deposition.)

[0096] As another preferred example, in the above Chemical Formula 1, X can be iodine. Within this range, it has the advantages of improving film crystallinity, suppressing side reactions, and thus more excellent reduction effect of process by-products.)

[0097] The compound represented by the above chemical formula 1 is a tertiary alkyl compound substituted with a halogen. As specific examples, it may be selected from one or more of 2-chloro-2-methylpropane, 2-chloro-2-methylbutane, 2-chloro-2-methylpentane, 3-chloro-3-methylpentane, 3-chloro-3-methylhexane, 3-chloro-3-ethylpentane, 3-chloro-3-ethylhexane, 4-chloro-4-methylheptane, 4-chloro-4-ethylheptane, 4-chloro-4-propylheptane, 2-bromo-2-methylpropane, 2-bromo-2-methylbutane, 2-bromo-2-methylpentane, 3-bromo-3-methylpentane, 3-bromo-3-methylhexane, 3-bromo-3-ethylpentane, 3-bromo-3-ethylhexane, 4-bromo-4-methylheptane, 4-bromo-4-ethylheptane, 4-bromo-4-propylheptane, 2-iodo-2-methylpropane, 2-iodo-2-methylbutane, 2-iodo-2-methylpentane, 3-iodo-3-methylpentane, 3-iodo-3-methylhexane, 3-iodo-3-ethylpentane, 3-iodo-3-ethylhexane, 4-iodo-4-methylheptane, 4-iodo-4-ethylheptane, 4-iodo-4-propylheptane, 2-fluoro-2-methylpropane, 2-fluoro-2-methylbutane, 2-fluoro-2-methylpentane, 3-fluoro-3-methylpentane, 3-fluoro-3-methylhexane, 3-fluoro-3-ethylpentane, 3-fluoro-3-ethylhexane, 4-fluoro-4-methylheptane, 4-fluoro-4-ethylheptane, 4-fluoro-4-propylheptane. Preferably, it may be selected from one or more of 2-chloro-2-methylpropane, 2-chloro-2-methylbutane, 3-chloro-3-methylpentane, tert-butyl chloride, 2-bromo-2-methylpropane, 2-bromo-2-methylbutane, 3-bromo-3-methylpentane, tert-butyl bromide, 2-iodo-2-methylpropane, 2-iodo-2-methylbutane, 3-iodo-3-methylpentane, tert-butyl iodide, 2-fluoro-2-methylpropane, 2-fluoro-2-methylbutane, 3-fluoro-3-methylpentane, and tert-butyl fluoride. At this time, a masking region for a silicon-based thin film is provided. Therefore, the effect of adjusting the growth rate of the thin film is significant, the effect of removing process by-products is also significant, and the step coverage improvement and film quality improvement effects are excellent.

[0098] As an example, the compound represented by the above Chemical Formula 1 can be a saturated compound with a refractive index (a) in the range of 1.38 to 1.52, and at the same time, the vapor pressure (mmHg, b) measured at 25 °C divided by the value of the above refractive index (a) (b / a) in the range of 0.003 to 0.033. A masking region for forming a silicon-based film is formed on the substrate to reduce the deposition rate of the silicon-based film and appropriately reduce the film growth rate, so that even when forming a film on a substrate with a complex structure, the step coverage and the thickness uniformity of the film can be significantly improved, and not only the adsorption of the film precursor is prevented, but also the adsorption of process by-products is prevented, thus having the advantages of effectively protecting the surface of the substrate and effectively removing process by-products.

[0099] As a specific example, the compound represented by the above Chemical Formula 1 can be a saturated compound with a refractive index (a) in the range of 1.38 to 1.51, and at the same time, the vapor pressure (mmHg, b) measured at 25 °C divided by the value of the above refractive index (a) (b / a) in the range of 0.003 to 0.0325. Preferably, it can be a saturated compound with a refractive index (a) in the range of 1.383 to 1.505, and at the same time, the vapor pressure (mmHg, b) measured at 25 °C divided by the value of the above refractive index (a) (b / a) in the range of 0.0035 to 0.0324. At this time, a masking region for forming a silicon-based film is formed on the substrate to reduce the deposition rate of the silicon-based film and appropriately reduce the film growth rate, so that even when forming a film on a substrate with a complex structure, the step coverage and the thickness uniformity of the film can be significantly improved, and not only the adsorption of the film precursor is prevented, but also the adsorption of process by-products is prevented, thus having the advantages of effectively protecting the surface of the substrate and effectively removing process by-products.

[0100] The above masking compound can provide a masking region for a silicon-based film.

[0101] As an example, the above masking region for a silicon-based film can be formed on the entire substrate or a part of the substrate on which the above silicon-based film is to be formed.

[0102] The above masking region for a silicon-based film does not remain in the above film.

[0103] At this time, unless otherwise defined, not remaining means that when analyzing the components by XPS, the C element is 0.1 atomic % (atom %), the Si element is less than 0.1 atomic % (atom %), the N element is less than 0.1 atomic % (atom %), and the halogen element is less than 0.1 atomic % (atom %).

[0104] As a specific example, the content of the halogen compound in the above-mentioned silicon-based thin film may be 0.01% or less.

[0105] The above-mentioned silicon-based thin film can be used as an anti-diffusion film, an etch stop film, or a charge trap, but is not limited thereto.

[0106] Preferably, the above-mentioned masking compound may be a compound with a purity of 99.9% or more, a compound with a purity of 99.95% or more, or a compound with a purity of 99.99% or more. For reference, when using a compound with a purity less than 99%, impurities may be formed. Therefore, substances with a purity of 99% or more should be used as much as possible.

[0107] Preferably, the compound represented by the above chemical formula 1 is used in an atomic layer deposition (ALD) process. At this time, it has the advantages of effectively protecting the surface of the substrate as a masking compound while not hindering the adsorption of the precursor compound, and effectively removing process by-products.

[0108] Preferably, the compound represented by the above chemical formula 1 is a liquid at room temperature (25 °C), and the density may be 0.75 - 2.5 g / cm 3 or 0.8 - 1.5 g / cm 3 , the vapor pressure (25 °C) may be 0.1 - 300 mmHg or 1 - 300 mmHg, and the solubility in water (25 °C) may be 200 mg / L or less. Within this range, it has the effect of effectively forming a masking region, and excellent step coverage, film thickness uniformity, and film quality improvement.

[0109] More preferably, the density of the compound represented by the above chemical formula 1 may be 0.75 - 2.0 g / cm 3 or 0.8 - 1.3 g / cm 3 , the vapor pressure (25 °C) may be 1 - 260 mmHg, and the solubility in water (25 °C) may be 160 mg / L or less. Within this range, it has the effect of effectively forming a masking region, and excellent step coverage, film thickness uniformity, and film quality improvement.

[0110] The method for forming a silicon-based thin film of the present invention includes the following steps: injecting the masking compound represented by chemical formula 1 into the ALD chamber and allowing it to adsorb on the surface of the loaded substrate. At this time, a masking region for the silicon-based thin film is formed on the substrate to reduce the deposition rate of the silicon-based thin film and appropriately reduce the film growth rate, so that even when forming a film on a substrate with a complex structure, the step coverage and film thickness uniformity can be greatly improved.

[0111] [Chemical formula 1]

[0112]

[0113] (In the above, A is carbon,

[0114] The above R 1 and R 3 are independently alkyl groups having 1 to 6 carbon atoms,

[0115] The above R 2 is independently an alkyl group having 1 to 6 carbon atoms or has a functional group of the formula BR 4 R 5 R 6 wherein B is carbon bonded to the above A, and the above R 4 and R 5 and R 6 are independently hydrogen, an alkyl group having 1 to 6 carbon atoms, fluorine (F), chlorine (Cl), bromine (Br), or iodine (I),

[0116] The above X is fluorine (F), chlorine (Cl), bromine (Br), or iodine (I) which is a halogen element.)

[0117] In the step of masking the surface of the substrate with the above masking compound, the feeding time of the masking compound to the surface of the substrate per cycle is preferably 0.01 to 20 seconds, more preferably 0.02 to 20 seconds, still more preferably 0.04 to 20 seconds, and further preferably 0.05 to 20 seconds. Within this range, it has the advantages of low thin film growth rate, excellent step coverage, and economy.

[0118] In the present invention, the feeding time of the masking compound is based on the volume of the chamber of 15 to 20 L and the flow rate of 0.5 to 5 mg / s. More specifically, it is based on the volume of the chamber at 18 L and the flow rate of 1 to 2 mg / s.

[0119] As a preferred embodiment, the above-described thin film forming method may include: a masking step of vaporizing the above-described masking compound to mask the surface of the substrate loaded in the ALD chamber; a first purge step of purging the inside of the above-described chamber with a purge gas; an adsorption step of vaporizing a precursor compound and adsorbing it onto the surface of the substrate loaded in the chamber; a second purge step of purging the inside of the above-described chamber with a purge gas; a gas supply step of supplying a reaction gas to the inside of the above-described chamber; and a third purge step of purging the inside of the above-described chamber with a purge gas. At this time, the steps from the above-described masking step to the third purge step can be regarded as a unit cycle, and the above-described cycle can be repeatedly implemented until a thin film with a desired thickness is obtained. And when the masking compound of the present invention is introduced and adsorbed onto the substrate prior to the precursor compound in one cycle in this way, even when deposition is performed at a high temperature, the thin film growth rate can be appropriately reduced, and the by-products generated in the process can be effectively removed. Therefore, it has the advantages of reducing the resistivity of the thin film and significantly improving the step coverage.

[0120] As another preferred embodiment, the above-described thin film forming method may include the following steps: an adsorption step of vaporizing a precursor compound and adsorbing it onto the surface of the substrate loaded in the chamber; a first purge step of purging the inside of the above-described chamber with a purge gas; an adsorption step of vaporizing the above-described masking compound and adsorbing it onto the surface of the substrate loaded in the chamber; a second purge step of purging the inside of the above-described chamber with a purge gas; a gas supply step of supplying a reaction gas to the inside of the above-described chamber; and a third purge step of purging the inside of the above-described chamber with a purge gas. At this time, the steps from the above-described precursor compound adsorption step to the third purge step can be regarded as a unit cycle, and the above-described cycle can be repeatedly implemented until a thin film with a desired thickness is obtained. And when the masking compound of the present invention is introduced and adsorbed onto the substrate after the precursor compound in one cycle in this way, the above-described masking compound can act as an activator for thin film formation. At this time, the thin film growth rate is increased, and the density and crystallinity of the thin film are improved. Therefore, it has the advantages of reducing the resistivity of the thin film and significantly improving the electrical characteristics.

[0121] As a preferred example, in the thin film forming method of the present invention, the masking compound of the present invention can be introduced and adsorbed onto the substrate prior to the precursor compound in one cycle. At this time, even when the thin film is deposited at a high temperature, the thin film growth rate can be appropriately reduced, thereby significantly reducing the by-products in the process and significantly improving the step coverage. Moreover, the crystallinity of the thin film is increased to reduce the resistivity of the thin film. And even when applied to semiconductor devices with a large aspect ratio, the thickness uniformity of the thin film can be significantly improved, thereby ensuring the reliability of the semiconductor device.

[0122] As an example, in the above-described thin film forming method, when depositing the above-described masking compound before or after depositing the precursor compound, if necessary, the number of repetitions of the unit cycle to be performed may be 1 to 99,999 times, preferably 10 to 10,000 times, more preferably 50 to 5,000 times, and even more preferably 100 to 2,000 times. Within this range, the desired thickness of the thin film can be obtained, and the effects to be achieved by the present invention can be sufficiently obtained.

[0123] The above-described precursor compound is a molecule composed of Si and one or more selected from C, N, H, and Cl. When it is a silicon precursor having a vapor pressure of 2 mTorr to 75 kTorr at 25°C, even if it is naturally oxidized, the effect of forming a masking region based on the above-described masking compound can be maximized.

[0124] In the present invention, as an example, the above-described chamber may be an ALD chamber or a CVD chamber.

[0125] In the present invention, a post-treatment step may be included. After vaporizing and injecting the above-described masking compound or precursor compound, plasma post-treatment is performed. At this time, the growth rate of the thin film can be adjusted and process by-products can be reduced.

[0126] When the above-described masking compound is adsorbed on the substrate first and then the above-described precursor compound is adsorbed, or when the above-described precursor compound is adsorbed first and then the above-described masking compound is adsorbed, in the step of purging the unadsorbed masking compound, the amount of the purge gas introduced into the interior of the above-described chamber only needs to be sufficient to remove the unadsorbed masking compound. As an example, it may be 10 to 100,000 times, preferably 50 to 50,000 times, more preferably 100 to 10,000 times. Within this range, the unadsorbed masking compound can be sufficiently removed to form a uniform thin film and prevent deterioration of the film quality. Here, the input amounts of the above-described purge gas and masking compound are based on one cycle, and the volume of the masking compound represents the volume of the vaporized masking compound vapor.

[0127] As a specific example, when injecting the above-described masking compound (per cycle) at a flow rate of 1.66 mL / s and an injection time of 0.5 sec, and in the step of purging the unadsorbed masking compound, injecting the purge gas (per cycle) at a flow rate of 166.6 mL / s and an injection time of 3 sec, the injection amount of the purge gas is 602 times the injection amount of the masking compound.

[0128] In addition, in the step of purging the unadsorbed precursor compound described above, the amount of the purge gas introduced into the interior of the ALD chamber only needs to be sufficient to remove the unadsorbed precursor compound. As an example, it can be 10 to 100,000 times the volume of the precursor compound introduced into the interior of the ALD chamber, preferably 50 to 50,000 times, more preferably 100 to 10,000 times. Within this range, the unadsorbed precursor compound can be sufficiently removed to form a uniform thin film and prevent deterioration of the film quality. Herein, the amounts of the purge gas and the precursor compound introduced are each based on one cycle, and the volume of the precursor compound represents the volume of the vaporized precursor compound vapor.

[0129] In addition, in the purge step immediately following the above reaction gas supply step, as an example, the amount of the purge gas introduced into the interior of the ALD chamber can be 10 to 100,000 times the volume of the reaction gas introduced into the interior of the ALD chamber, preferably 50 to 50,000 times, more preferably 100 to 10,000 times. Within this range, the desired effects can be sufficiently obtained. Herein, the amounts of the purge gas and the reaction gas introduced are each based on one cycle.

[0130] Preferably, the masking compound and the precursor compound can be transported into the ALD chamber by the VFC method, the DLI method, or the LDS method. More preferably, they can be transported into the chamber by the LDS method.

[0131] As an example, the substrate loaded in the chamber can be heated to 300 to 800 °C. As a specific example, it can be heated to 500 to 700 °C. The masking compound or the precursor compound can be injected onto the substrate in an unheated or heated state. Depending on the deposition efficiency, it is also possible to perform heating during the deposition process after injection in an unheated state. As an example, injection can be carried out onto the substrate at 300 to 800 °C for 1 to 30 seconds.

[0132] Preferably, the ratio of the amount (mg / cycle) of the masking compound to the amount of the precursor compound introduced into the chamber can be 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 effect of improving the step coverage and the effect of reducing process by-products are significant.

[0133] In the present invention, as an example, the precursor compound can be introduced into the chamber in a manner mixed with a non-polar solvent. At this time, it has the advantage of being easy to adjust the viscosity and vapor pressure of the precursor compound.

[0134] Preferably, the above non-polar solvent can be selected from one or more of alkanes and cycloalkanes. At this time, it contains an organic solvent with very low reactivity and easy moisture management, and has the advantage of being able to improve step coverage even when the deposition temperature increases during film formation.

[0135] As a more preferred example, the above non-polar solvent may contain C 1 ~C 10 alkane or C 3 ~C 10 cycloalkane, preferably C 3 ~C 10 cycloalkane. At this time, it has the advantages of very low reactivity and easy moisture management.

[0136] In the present invention, C 1 、C 3 etc. represent the number of carbon atoms.

[0137] Preferably, the above cycloalkane can be a monocycloalkane of C 3 ~C 10 . Among the above monocycloalkanes, cyclopentane is a liquid at room temperature and has the highest vapor pressure. Therefore, it is preferred in the chemical vapor deposition process, but not limited thereto.

[0138] As an example, the solubility of the above non-polar solvent in water (25 °C) is 200 mg / L or less, preferably 50 - 400 mg / L, more preferably 135 - 175 mg / L. Within this range, it has the advantages of low reactivity with the precursor compound and easy moisture management.

[0139] In the present invention, the solubility is based on the measurement methods and standards commonly used in the art. As an example, the saturated solution can be measured by HPLC method.

[0140] Preferably, based on the total weight of the precursor compound and the non-polar solvent added, the content of the above non-polar solvent can be 5 - 95% by weight, more preferably 10 - 90% by weight, even more preferably 40 - 90% by weight, and most preferably 70 - 90% by weight.

[0141] If the content of the above non-polar solvent input is greater than the above upper limit value, impurities will be induced, resulting in an increase in the resistance and the impurity value in the film. When the content of the above organic solvent input is less than the above lower limit value, there are disadvantages that the effects of improving step coverage due to the addition of the solvent and reducing impurities such as chlorine (Cl) ions are not significant.

[0142] As an example, when the above-described masking compound is used in the above-described silicon-based thin film forming method, the reduction rate of the film growth rate per cycle ( / cycle) is 5% or less, preferably 10% or less, more preferably 20% or less, still more preferably 30% or less, further preferably 40% or less, and most preferably 45% or less. Within this range, the step coverage and the film thickness uniformity are excellent.

[0143] [Mathematical formula 1]

[0144] Reduction rate of film growth rate per cycle (%) = [(Film growth rate per cycle when using the masking compound - Film growth rate per cycle when not using the masking compound) / Film growth rate per cycle when not using the masking compound] × 100

[0145] In the above Mathematical formula 1, the film growth rate per cycle when using or not using the masking compound represents the film deposition thickness per cycle That is, the deposition rate. As an example, the above deposition rate can be the average deposition rate obtained by dividing the final thickness of the film measured using an ellipsometer by the total number of cycles. In order to measure the thickness more accurately, the above optical thickness (ellipsometry) measurement method is correlated through transmission electron microscope (TEM) analysis to improve the thickness error.

[0146] In the above Mathematical formula 1, "when not using the masking compound" means a case where a film is formed by adsorbing only the precursor compound on the substrate in the film deposition process. As a specific example, it means a case where a film is formed by omitting the step of adsorbing the masking compound and the step of purging the unadsorbed masking compound in the above-described thin film forming method.

[0147] Based on the film thickness, the halogen intensity (c / s) remaining in the film measured by SIMS in the above-described silicon-based thin film forming method is preferably 4,000 ppm or less, more preferably 3,700 ppm or less, still more preferably 3,500 ppm or less, further preferably 2,000 ppm or less, and more preferably 0 ppm or close thereto. Within this range, the effects of preventing corrosion and deterioration are excellent.

[0148] In the present invention, the purge is preferably 1,000 to 50,000 sccm (Standard Cubic Centimeter per Minute), more preferably 2,000 to 30,000 sccm, and even more preferably 2,500 to 15,000 sccm. Within this range, there are advantages in appropriately controlling the film growth rate per cycle and depositing in a single atomic monolayer or close thereto, which is beneficial in terms of film quality.

[0149] The above-mentioned ALD (Atomic Layer Deposition process) is very advantageous in the manufacture of integrated circuits (ICs) that require high aspect ratios. In particular, based on the self-limiting film growth mechanism, it has advantages such as excellent conformality, uniform coverage, and precise thickness control.

[0150] As an example, the above-mentioned film formation method can be implemented at a deposition temperature in the range of 50 to 800 °C, preferably at a deposition temperature in the range of 300 to 700 °C, more preferably at a deposition temperature in the range of 500 to 700 °C, and even more preferably at a deposition temperature in the range of 600 to 650 °C. Within this range, there is an effect of realizing the ALD process characteristics and growing a film with excellent film quality.

[0151] As an example, the above-mentioned film formation method can be implemented at a deposition pressure in the range of 0.01 to 20 Torr, preferably at a deposition pressure in the range of 0.1 to 20 Torr, more preferably at a deposition pressure in the range of 0.1 to 10 Torr, and most preferably at a deposition pressure in the range of 0.3 to 5 Torr. Within this range, there is an effect of obtaining a film with uniform thickness.

[0152] In the present invention, the deposition temperature and deposition pressure can be measured by the temperature and pressure formed in the deposition chamber or by the temperature and pressure applied to the substrate in the deposition chamber.

[0153] Preferably, the above-mentioned silicon-based film formation method may include the following steps: heating the temperature in the chamber to the deposition temperature before introducing the above-mentioned masking compound into the chamber; and / or injecting an inert gas into the chamber for purging before introducing the above-mentioned masking compound into the chamber.

[0154] In addition, in the present invention, a thin film manufacturing apparatus capable of implementing the above-described silicon-based thin film manufacturing method may include an ALD chamber, a first vaporizer for vaporizing a masking compound, a first transfer unit for transferring the vaporized masking compound into the ALD chamber, a second vaporizer for vaporizing a thin film precursor, and a second transfer unit for transferring the vaporized thin film precursor into the ALD chamber. Among them, the vaporizer and the transfer unit may be vaporizers and transfer units commonly used in the art.

[0155] As a specific example, the above thin film forming method will be described. First, a substrate on which a thin film is to be formed is placed in a deposition chamber capable of performing atomic layer deposition.

[0156] The above substrate may include semiconductor substrates such as a silicon substrate and silicon oxide.

[0157] The above substrate may further have a conductive layer or an insulating layer formed on its upper part.

[0158] The above masking compound and the precursor compound or a mixture thereof with a non-polar solvent are respectively prepared to deposit a thin film on the substrate placed in the above deposition chamber.

[0159] After that, after injecting the prepared masking compound into the vaporizer, it is changed into a vapor phase, transferred to the deposition chamber, adsorbed on the substrate, and then purged to remove the unadsorbed masking compound.

[0160] Next, after injecting the prepared precursor compound or a mixture thereof with a non-polar solvent (thin film forming composition) into the vaporizer, it is changed into a vapor phase, transferred to the deposition chamber, adsorbed on the substrate, and then the unadsorbed precursor compound / thin film forming composition is purged.

[0161] In the present invention, according to needs, the order of the following processes may be swapped and implemented: the process of purging to remove the unadsorbed masking compound after adsorbing the above masking compound on the substrate; and the process of purging to remove the unadsorbed precursor compound after adsorbing the precursor compound on the substrate.

[0162] In the present invention, as an example, the method of delivering a masking compound, a precursor compound (composition for film formation), etc. to the deposition chamber may use the vapor flow control (VFC) method of delivering a volatile gas using a mass flow controller (MFC) or the liquid delivery system (LDS) method of delivering a liquid using a liquid mass flow controller (LMFC). Preferably, the LDS method is used.

[0163] At this time, as the carrier gas or dilution gas for delivering the masking compound, the precursor compound, etc. onto the substrate, a mixed gas of one or more selected from argon (Ar), nitrogen (N 2 ) and helium (He) can be used, but it is not limited thereto.

[0164] In the present invention, as an example, the purge gas can use an inert gas. Preferably, the above carrier gas or dilution gas can be used.

[0165] Next, a reaction gas is supplied. The above reaction gas can be any reaction gas conventionally used in the art. Preferably, it can contain a nitriding agent. The above nitriding agent reacts with the precursor compound adsorbed on the substrate to form a nitride film.

[0166] Preferably, the above nitriding agent can be nitrogen (N 2 ), hydrazine (N 2 H 4 ) or a mixture of nitrogen and hydrogen.

[0167] The above reaction gas can only contain hydrogen (H 2 ). The above hydrogen reacts with the precursor compound adsorbed on the substrate to form a silicon film.

[0168] Next, the unreacted residual reaction gas is purged with an inert gas. Thereby, not only can the excess reaction gas be removed, but also the by-products generated can be removed together.

[0169] As described above, as an example, the above method for forming a silicon-based film can use the following steps as a unit cycle, and repeat the above unit cycle to form a film with a desired thickness: the step of masking the substrate with a masking compound; the step of purging the unadsorbed masking compound; the step of adsorbing the precursor compound / composition for film formation onto the substrate; the step of purging the unadsorbed precursor compound / composition for film formation; the step of supplying a reaction gas; the step of purging the residual reaction gas.

[0170] As another example, the above-described silicon-based thin film forming method may use the following steps as a unit cycle and repeat the above unit cycle to form a thin film of a desired thickness: a step of adsorbing a precursor compound / thin film forming composition onto a substrate; a step of purging the precursor compound / thin film forming composition that has not been adsorbed; a step of adsorbing a masking compound onto the substrate; a step of purging the masking compound that has not been adsorbed; a step of supplying a reaction gas; and a step of purging the remaining reaction gas.

[0171] As an example, the number of repetitions of the above unit cycle may be 1 to 99,999 times, preferably 10 to 10,000 times, more preferably 50 to 5,000 times, and even more preferably 100 to 2,000 times. Within this range, there is an effect of well exhibiting the desired thin film characteristics.

[0172] The present invention also provides a semiconductor substrate, which is manufactured by the silicon-based thin film forming method of the present invention. At this time, the step coverage and thickness uniformity of the thin film are very excellent, and the density and electrical characteristics of the thin film are excellent.

[0173] Preferably, the thickness of the manufactured thin film is 100 nm or less. Based on a thin film thickness of 10 nm or 20 nm, the etching rate (WER@LAL500 60 s) < 2 nm / min, and both the residual carbon content and the residual halogen content satisfy 0.01% or less, and the step coverage rate is 90% or more. Within this range, the performance as an insulating film and a charge trap layer is excellent, but it is not limited thereto.

[0174] As an example, the thickness of the above thin film may be 1 to 100 nm, preferably 1 to 50 nm, more preferably 3 to 25 nm, and even more preferably 5 to 20 nm. Within this range, there is an effect of excellent thin film characteristics.

[0175] Preferably, the residual carbon content and the residual halogen content of the above thin film may be 0.1% or less or 0 to 0.01%, more preferably 0 to 0.001%, and even more preferably 0 to 0.0001%. Within this range, the thin film characteristics are excellent and there is an effect of reducing the thin film growth rate. Within this range, an appropriate amount of carbon in the thin film forms deep trap sites in the band gap of the thin film to improve the charge storage characteristics and improve the film density, thereby having excellent insulating film characteristics such as improving the etching rate. Moreover, the lower the residual amount of halogen in the thin film, the better the film quality, so it is preferred.

[0176] As an example, the step coverage of the above-mentioned thin film can be 90% or more, preferably 92% or more, more preferably 95% or more. Within this range, even for a thin film with a complex structure, it can be easily deposited on a substrate. Therefore, it has the advantage of being applicable to a new generation of semiconductor devices.

[0177] As an example, the above-mentioned thin film manufactured may include a silicon nitride film (Si x N y , where 0 < x ≤ 4.5, 0 < y ≤ 4.5, preferably 0.5 ≤ x ≤ 4.5, 0.5 ≤ y ≤ 4.5, more preferably 2.5 ≤ x ≤ 4.5, 2.5 ≤ y ≤ 4.5). At this time, it has the advantages of being able to be used as an anti-diffusion film, an etch stop film, or a charge trap of a semiconductor device.

[0178] As an example, as needed, the above-mentioned thin film can be a multi-layer structure of two or three layers. As a specific example, the multi-layer film with a two-layer structure can be a structure of a lower layer film - a middle layer film. As a specific example, the multi-layer film with a three-layer structure can be a structure of a lower layer film - a middle layer film - an upper layer film.

[0179] As an example, the above-mentioned lower layer film may contain one or more selected from Si, SiO 2 , MgO, Al 2 O 3 , CaO, ZrSiO 4 , ZrO 2 , HfSiO 4 , Y 2 O 3 , HfO 2 , LaLuO 2 , Si 3 N 4 , SrO, La 2 O 3 , Ta 2 O 5 , BaO, TiO 2 of more than one kind.

[0180] As an example, the above-mentioned middle layer film may contain Ti x N y , preferably, it may contain TN.

[0181] As an example, the above-mentioned upper layer film may contain one or more selected from W and Mo.

[0182] Hereinafter, preferred embodiments and drawings are presented to help understand the present invention. Those skilled in the art are aware that the following embodiments and drawings are only for illustrating the present invention, and various changes and modifications can be made within the scope of the present invention and the technical idea, and these deformations and modifications also fall within the scope of the appended claims.

[0183] [Example]

[0184] Example 1

[0185] Prepare tert - butyl iodide as a masking compound and Si 2 Cl 6 .

[0186] Load the prepared masking compound into a can and supply it to a vaporizer heated to 120 °C at a flow rate of 0.05 g / min using a Liquid Mass Flow Controller (LMFC) at room temperature. After 1 second of introducing the masking compound vaporized into the vapor phase in the vaporizer into the deposition chamber loaded with the substrate, argon is supplied at 5000 sccm for 2 seconds for argon purge. At this time, the pressure in the reaction chamber is controlled to 2.5 Torr.

[0187] Next, load the prepared Si 2 Cl 6 into another can and supply it to another vaporizer heated to 150 °C at a flow rate of 0.05 g / min using a Liquid Mass Flow Controller (LMFC) at room temperature. After 1 second of introducing the Si 2 Cl 6 vaporized into the vapor phase in the vaporizer into the deposition chamber, argon is supplied at 5000 sccm for 2 seconds for argon purge. At this time, the pressure in the reaction chamber is controlled to 2.5 Torr.

[0188] Next, introduce ammonia as a reactive gas into the above - mentioned reaction chamber at 1000 sccm for 3 seconds, and then perform argon purge for 3 seconds. At this time, the substrate on which the metal thin film is to be formed is heated to 460 °C. Repeat this process 200 - 400 times to form a 10 - nm - thick SiN thin film as a self - limiting atomic layer (equivalent to Si x N y thin film, where x and y are positive numbers from 0.5 to 4.5 respectively).

[0189] To confirm the etching rate, immerse the SiN thin film in the LAL500 etchant for 60 seconds for etching, then measure the reduced thickness by optical thickness measurement method and calculate the etching rate.

[0190] Example 2

[0191] A SiN thin film as a self-limiting atomic layer was formed in the same manner as in Example 1, except that tert-butyl bromide was used as the masking compound in Example 1.

[0192] To confirm the etching rate, the SiN thin film was immersed in the LAL500 etchant for 60 seconds for etching. After that, the reduced thickness was measured by optical thickness measurement, and the etching rate was calculated.

[0193] Example 3

[0194] tert-butyl chloride as a masking compound and Si 2 Cl 6 .

[0195] The prepared masking compound was loaded into a can and supplied to a vaporizer heated to 120 °C at a flow rate of 0.1 g / min using a Liquid Mass Flow Controller (LMFC) at room temperature. After the masking compound vaporized into the vapor phase in the vaporizer was introduced into the deposition chamber loaded with the substrate for 5 - 30 seconds, argon was supplied at 1000 sccm for 30 seconds for argon purge. At this time, the pressure in the reaction chamber was controlled to 1.0 Torr.

[0196] Next, the prepared Si 2 Cl 6 was loaded into another can and supplied to another vaporizer heated to 150 °C at a flow rate of 0.1 g / min using a Liquid Mass Flow Controller (LMFC) at room temperature. After the thin film precursor compound vaporized into the vapor phase in the vaporizer was introduced into the deposition chamber for 5 seconds - 30 seconds, argon was supplied at 1000 sccm for 30 seconds for argon purge. At this time, the pressure in the reaction chamber was controlled to 1.0 Torr.

[0197] Next, ammonia was introduced as a reactive gas into the above reaction chamber at 1000 sccm for 30 seconds, and then argon purge was performed for 30 seconds. At this time, the substrate on which the metal thin film was to be formed was heated to 500 - 650 °C. This process was repeated 200 - 400 times to form a 10 nm thick SiN thin film as a self-limiting atomic layer (equivalent to Si x N y thin film, where x and y are positive numbers from 0.5 to 4.5 respectively).

[0198] To confirm the etching rate, using the LAL500 etching solution, the SiN thin film was immersed in the etching solution for 60 seconds for etching. After that, the reduced thickness was measured by optical thickness measurement method, and the etching rate was calculated.

[0199] Example 4

[0200] 2-chloro-2-methyl butane as the masking compound and Si as the film precursor compound were prepared separately. 2 Cl 6 .

[0201] The prepared masking compound was loaded into a can and supplied to a vaporizer heated to 120 °C at a flow rate of 0.1 g / min using a Liquid Mass Flow Controller (LMFC) at room temperature. After the masking compound vaporized into the vapor phase in the vaporizer was introduced into the deposition chamber loaded with the substrate for 5 - 30 seconds, argon was supplied at 1000 sccm for 30 seconds for argon purge. At this time, the pressure in the reaction chamber was controlled to 1.0 Torr.

[0202] Next, the prepared Si 2 Cl 6 was loaded into another can and supplied to another vaporizer heated to 150 °C at a flow rate of 0.1 g / min using a Liquid Mass Flow Controller (LMFC) at room temperature. After the film precursor compound vaporized into the vapor phase in the vaporizer was introduced into the deposition chamber for 5 seconds - 30 seconds, argon was supplied at 1000 sccm for 30 seconds for argon purge. At this time, the pressure in the reaction chamber was controlled to 1.0 Torr.

[0203] Next, ammonia was introduced as the reactive gas into the above reaction chamber at 1000 sccm for 30 seconds, and then argon purge was carried out for 30 seconds. At this time, the substrate on which the metal thin film was to be formed was heated to 500 - 650 °C. This process was repeated 200 - 400 times to form a 10 - nm - thick SiN thin film as a self - limiting atomic layer (equivalent to Si x N y thin film, where x and y are positive numbers from 0.5 to 4.5 respectively).

[0204] To confirm the etching rate, using the LAL500 etching solution, the SiN thin film was immersed in the etching solution for 60 seconds for etching. After that, the reduced thickness was measured by optical thickness measurement method, and the etching rate was calculated.

[0205] Example 5

[0206] Except for separately preparing tert-butyl chloride as the masking compound and SiH 2 Cl 2 as the film precursor compound, the same procedures as in Example 3 above were repeated.

[0207] To confirm the etching rate, using the LAL500 etching solution, the SiN film was immersed in the etching solution for 60 seconds for etching. After that, the reduced thickness was measured by optical thickness measurement method, and the etching rate was calculated.

[0208] Example 6

[0209] Except for separately preparing 2-chloro-2-methyl butane as the masking compound and SiH 2 Cl 2 as the film precursor compound, the same procedures as in Example 4 above were repeated.

[0210] To confirm the etching rate, using the LAL500 etching solution, the SiN film was immersed in the etching solution for 60 seconds for etching. After that, the reduced thickness was measured by optical thickness measurement method, and the etching rate was calculated.

[0211] Comparative Example 1

[0212] Except for not using the masking compound in Example 1 and thus omitting the step of purging the unadsorbed masking compound, a SiN film was formed on the substrate in the same manner as in Example 1.

[0213] Comparative Example 2

[0214] Except for using n-pentane as the masking compound in Example 1, a SiN film as a self-limiting atomic layer was formed in the same manner as in Example 1.

[0215] Comparative Example 3

[0216] Except for using cyclopentane as the masking compound in Example 1, a SiN film as a self-limiting atomic layer was formed in the same manner as in Example 1.

[0217] Comparative Example 4

[0218] Except for not using the masking compound in Example 3 and thus omitting the step of purging the unadsorbed masking compound, a SiN film was formed on the substrate in the same manner as in Example 3.

[0219] Comparative Example 5

[0220] A SiN thin film was formed on a substrate in the same manner as in Example 4, except that the masking compound was not used in Example 4, and thus the step of purging the unadsorbed masking compound was omitted.

[0221] Comparative Example 6

[0222] A SiN thin film was formed on a substrate in the same manner as in Example 5, except that the masking compound was not used in Example 5, and thus the step of purging the unadsorbed masking compound was omitted.

[0223] Comparative Example 7

[0224] A SiN thin film was formed on a substrate in the same manner as in Example 6, except that the masking compound was not used in Example 6, and thus the step of purging the unadsorbed masking compound was omitted.

[0225] [Experimental Example]

[0226] 1) Deposition evaluation and deposition rate reduction

[0227] For the SiN thin films deposited in Examples 1 to 6 and Comparative Examples 1 to 7, the film growth rate was calculated by dividing the thickness of the film measured by an ellipsometer by the number of cycles, and the reduction rate of the film growth rate per cycle was calculated. The ellipsometer is a device that can measure optical properties such as the thickness or refractive index of a manufactured film using the polarization characteristics of light. Specifically, the calculation was performed using Equation 1.

[0228] [Equation 1]

[0229] Reduction rate of film growth rate per cycle (%) = [(Film growth rate per cycle when using the masking compound - Film growth rate per cycle when not using the masking compound) / Film growth rate per cycle when not using the masking compound] × 100

[0230] As a result, it was confirmed that in Examples 1 to 6 using the masking compound of the present invention, compared with Comparative Examples 1, 4, 5, 6, 7 that did not use the masking compound of the present invention, Comparative Example 2 using pentane, and Comparative Example 3 using cyclopentane, the reduction rate of the film growth rate per cycle was significantly improved.

[0231] First, comparing Example 1 using tert-butyliodide as the masking compound with Comparative Example 1 not containing tert-butyl iodide, it was confirmed that the deposition rate was / cycle Compared with that of Comparative Example 1 / cycle, the deposition rate decreased by more than 20%.

[0232] In addition, it was confirmed that Comparative Examples 2 and 3 using pentane or cyclopentane in place of the masking compound of the present invention also had the same deposition rate as Comparative Example 1. At this time, the decrease in the deposition rate indicates a change from CVD deposition characteristics to ALD deposition characteristics, and thus can be used as an index for improving the step coverage characteristics.

[0233] Furthermore, SIMS analysis was performed to verify whether carbon doping at the ppb level was possible, and the results obtained are shown in Figure 1 .

[0234] Specifically, Figure 1 is a SIMS analysis curve of the SiN thin film fabricated in Example 1 and Comparative Example 1.

[0235] As Figure 1 shown, it was confirmed that Cl was significantly reduced in Example 1 corresponding to the right curve compared to Comparative Example 1 corresponding to the left curve.

[0236] Furthermore, in Figure 2 , the deposition rates obtained in Example 3 and Example 4 using tert-butyl chloride and 2-chloro-2-methyl butane as masking compounds, respectively, were compared.

[0237] Figure 2 is a curve showing the change in the deposition rate of the masking compound of the present invention at different supply times. As Figure 2 shown, using Si 2 Cl 6 as the silicon precursor, and when 15 seconds of tert-butyl chloride masking compound was injected, an improved deposition rate ( / cycle → / cycle) was confirmed, and when 15 seconds of 2-chloro-2-methyl butane masking compound was injected, an improved deposition rate ( / cycle → / cycle) was confirmed.

[0238] Next, using Si 2 Cl 6 as the precursor, and the results of the deposition rate varying with the injection time of different types of masking compounds at 600 °C are shown in Table 1.

[0239] Table 1 shows the deposition evaluation results varying with the deposition temperature when using SiH 2 Cl 2 (DCS) as the silicon precursor.

[0240] Tert-butyl chloride was used as the masking compound, and the injection time and purge time of the masking compound in each ALD cycle were 5 seconds and 10 seconds, respectively.

[0241] Table 1

[0242]

[0243] As shown in Table 1 above, it was confirmed that at deposition temperatures of 500 °C and 600 °C, the deposition rate reduction effects were -64% and -65%, respectively.

[0244] 2) Cl impurity reduction characteristics

[0245] To compare the impurity reduction characteristics, i.e., the fixed by-product reduction characteristics, of the SiN films deposited in Examples 1 to 6 and Comparative Examples 1 to 7, SIMS analysis was performed, and the results are shown in Table 2.

[0246] Among them, the Cl reduction rate (%) was calculated by Equation 2.

[0247] [Equation 2]

[0248] Cl reduction rate = (SIMS Cl intensity of Comparative Example 1 - SIMS Cl intensity of Example) / (SIMS Cl intensity of Example) × 100

[0249] Table 2

[0250]

[0251] * Reference thickness of the sample film: 10 nm

[0252] As shown in Table 2 above, compared with Comparative Example 1 that did not use the masking compound of the present invention or Comparative Example 2 that used pentane, in Example 1 that used the masking compound of the present invention, at deposition temperatures of 500 °C and 550 °C, the Cl intensity decreased significantly, thus confirming excellent impurity reduction characteristics.

[0253] 3) C film impurity doping characteristics

[0254] To perform quantitative analysis of the elements in the SiN films deposited in Example 3 and Comparative Example 4, XPS quantitative analysis was performed.

[0255] Specifically, the silicon precursor used was Si 2 Cl 6 , the implantation time of the masking compound was 15 seconds, and the deposition was carried out at 600 °C.

[0256] In Figure 3 a graph is shown, which plots the results of analyzing elements at different depths by Ar sputtering for the SiN films fabricated in Examples 3 to 4 and Comparative Example 4.

[0257] As Figure 3 shown, regardless of the masking compound, no increase in C impurities caused by the masking compound was confirmed. For reference, trace amounts of oxygen are the result of natural oxidation and contamination due to exposure to external air.

[0258] Furthermore, it was verified by SIMS analysis whether carbon doping at the ppb level was possible, and the obtained results are shown in Figure 3 .

[0259] Specifically, the silicon precursor used was Si 2 Cl 6 , tert-butyl chloride and 2-chloro-2-methyl butane were used as the masking compounds in Examples 3 and 4 respectively, while no masking compound was used in Comparative Example 4, and the implantation times were non-implantation, 5 seconds of implantation, 10 seconds of implantation, 15 seconds of implantation, 20 seconds of implantation, and the deposition was carried out at a temperature of 600 °C.

[0260] Figure 4 is the SIMS analysis graph of the SiN films fabricated in Example 3 and Comparative Example 4. As Figure 4 shown, no change in the contents of Si, Cl, and N was confirmed, but it was confirmed that the number of ions corresponding to the secondary ion mass of C released from the specimen increased by about 10 times. This C doping result also affects the film density, and thus, it can be further confirmed as the effect of improving the etching rate.

[0261] 4) Step coverage characteristics

[0262] Using TEM, the step coverage of the SiN films deposited on trench substrates with an aspect ratio of 23:1 in Examples 3 to 4 and Comparative Example 4 was confirmed, and it is shown in Figure 5 .

[0263] As Figure 5 shown, it was confirmed that as a result of using the masking compound of the present invention, the step coverage characteristics were improved from 81% to 93% and 96% respectively.

[0264] 5) Etching rate characteristics

[0265] The etching rates of the respective specimens in Examples 3 to 4 and Comparative Example 4 were analyzed and are shown in Table 3.

[0266] Table 3

[0267] Category Etching rate (nm / min) Comparative Example 4 (Control Group SiN) 10.2 Example 3 (tert-Butyl Chloride - SiN) 8.7 Example 4 (2-Chloro-2-methylbutane - SiN) 7.8

[0268] As shown in Table 3 above, it was confirmed that as the film quality was improved by adopting the masked compound implantation process, the etching rates of Example 3 and Example 4 were improved from the etching rate of 10.2 nm / min in Comparative Example 4 to 8.7 nm / min and 7.8 nm / min, respectively.

Claims

1. A masking compound for a silicon-based thin film, characterized in that, The above-mentioned silicon-based thin film has a film composition of Si x N y , where x and y are positive numbers ranging from 0.5 to 4.5 respectively. the masking compound is a saturated compound represented by the following Chemical Formula 1, [Chemical Formula 1] wherein A is carbon, The above-mentioned R 1 and R 3 are independently alkyl groups having 1 to 6 carbon atoms, The above R 2 is independently an alkyl group having 1 to 6 carbon atoms or has a functional group of the formula BR 4 R 5 R 6 wherein B is a carbon atom bonded to A, and the above R 4 , R 5 and R 6 are independently hydrogen, an alkyl group having 1 to 6 carbon atoms, fluorine, chlorine, bromine or iodine. and X is a halogen element, which is fluorine, chlorine, bromine or iodine.

2. The masking compound for a silicon-based thin film according to claim 1, characterized in that, the refractive index a of the masking compound is in the range of 1.38 to 1.52, and at the same time, the vapor pressure b at 25 °C divided by the value of the refractive index a, that is, b / a is in the range of 0.003 to 0.033, wherein the unit of the vapor pressure is mmHg.

3. The masking compound for a silicon-based thin film according to claim 1, characterized in that, The above-mentioned silicon-based thin film is composed of Si 3 N 4 , Si 2 N 3 , Si 2 , SiN, or a mixture thereof.

4. The masking compound for a silicon-based thin film according to claim 1 or 2, characterized in that, the masking compound is used to provide a masking area for a silicon-based thin film.

5. The masking compound for a silicon-based thin film according to claim 4, characterized in that, the masking area for the silicon-based thin film is formed on the entire substrate or a part of the substrate on which the silicon-based thin film is to be formed.

6. The masking compound for a silicon-based thin film according to claim 4, characterized in that, the masking area for the silicon-based thin film does not remain in the silicon-based thin film, and the content of the halogen compound in the silicon-based thin film is less than 0.01% by weight.

7. The masking compound for a silicon-based thin film according to claim 1, characterized in that, the silicon-based thin film is used as an anti-diffusion film, an etch stop film or a charge trap.

8. A method for forming a silicon-based thin film, characterized in that, it includes the following steps: injecting a masking compound having a saturated structure represented by Chemical Formula 1 into a chamber to mask the surface of the loaded substrate, [Chemical Formula 1] wherein A is carbon, The above-mentioned R 1 and R 3 are each independently an alkyl group having 1 to 6 carbon atoms, The above R 2 is independently an alkyl group having 1 to 6 carbon atoms or has a functional group of the formula BR 4 R 5 R 6 wherein B is a carbon atom bonded to A above, and the above R 4 , R 5 and R 6 are independently hydrogen, an alkyl group having 1 to 6 carbon atoms, fluorine, chlorine, bromine or iodine. and X is a halogen element, which is fluorine, chlorine, bromine or iodine.

9. The method for forming a silicon-based thin film according to claim 8, characterized in that, the chamber is an atomic layer deposition chamber or a chemical vapor deposition chamber.

10. The method for forming a silicon-based thin film according to claim 8, characterized in that, the masking compound is transported into the chamber by a gas-phase flow control method, a direct liquid injection method or a liquid transfer system method, and the silicon-based thin film is a silicon nitride film.

11. A semiconductor substrate, characterized in that, it is manufactured by the method for forming a silicon-based thin film according to claim 8.

12. The semiconductor substrate according to claim 11, characterized in that, the silicon-based thin film has a multi-layer structure of two or three layers.

13. A semiconductor device, characterized in that, it includes the semiconductor substrate according to claim 11.

Images