Atomic layer deposition method of semiconductor film

Abstract

The invention discloses an atomic layer deposition method of a semiconductor film, and belongs to the technical field of semiconductor materials. The method comprises the following steps: introducing a precursor material and a deposition assistant material to deposit a substrate, purging with inert gas, introducing a co-reactant, and purging with inert gas again; circulating for several times, and depositing to obtain a semiconductor film. Compared with a traditional ALD deposition method, the deposition auxiliary material is adopted to assist deposition of the precursor material, the uniformity of the thin film can be effectively improved, and the impurity content in the thin film is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of semiconductor materials, and in particular relates to an atomic layer deposition method for a semiconductor thin film. Background Art

[0002] As semiconductor manufacturing process nodes enter the near-atomic scale, manufacturing accuracy must be at the atomic level, and films with high film thickness accuracy and high film quality are urgently required. In order to meet the corresponding manufacturing requirements, the existing technology widely adopts continuous spatially spaced atomic layer deposition (ALD) technology. The basic principle of ALD relies on the alternating introduction of two or more precursors in the reaction chamber to form an atomic-level film through chemical adsorption and reaction. This process is self-limiting, that is, each chemical adsorption will saturate the surface to avoid overreaction, thereby achieving precise control of the film thickness.

[0003] In the actual ALD deposition application process, a four-step cycle is usually included, that is, the substrate surface is alternately exposed to complementary chemical precursors, and repeated as many times as needed to obtain the desired coating thickness. However, on the same substrate, there will be local over-thickness and local over-thinness; in addition, during the ALD reaction process, if the side reaction products left after the precursor is introduced in the previous cycle cannot be completely removed, it will lead to the accumulation of impurities in the film, seriously affecting the effect of the film in semiconductor devices. Improving the uniformity of film thickness and reducing the impurity content in the film are still technical problems that need to be solved in ALD technology. Therefore, it is very necessary to find a deposition process that can improve the uniformity of the film, reduce the impurity content of the film, and thus improve the film quality of the film. Summary of the invention

[0004] The object of the present invention is to provide an atomic layer deposition method for semiconductor thin films to solve the problems of poor uniformity of film thickness and high impurity content in the existing ALD technology.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A method for atomic layer deposition of a semiconductor thin film comprises the following steps:

[0007] Precursor materials and deposition aid materials are introduced to deposit on the substrate, and after inert gas is purged, a co-reactant is introduced and the inert gas is purged again; the cycle is repeated several times to deposit a semiconductor film;

[0008] The deposition aid material comprises at least one of the following:

[0009] (1) Ether substances of the structure R1O-X-OR2, wherein R1 and R2 are independently selected from methyl or ethyl, and X is one or a group of C2-C5 alkyl, phenyl, carbonyl, C2-C6 alkenyl;

[0010] (2) The structure is Y-(CH2) n -CN nitrile substances, wherein Y is an unsaturated group and n is an integer of 0-5;

[0011] (3) Aromatic aldehydes;

[0012] (4) Pyridine and its alkynyl derivatives.

[0013] Furthermore, the chemical structural formula of the pyridine and its alkynyl derivatives is Formula 1:

[0014] Any one of x, y, and z is -(CH2) n -C≡C, the rest are -H, n is any integer ≥ 0;

[0015] In one embodiment, pyridine and its alkynyl derivatives include but are not limited to:

[0016]

[0017] Furthermore, in the ether substance with the structure of R1O-X-OR2, R1 and R2 are independently selected from methyl or ethyl, and X is one or a group of C2-C5 alkyl, phenyl.

[0018] In one embodiment, the ether substances having the structure of R1O-X-OR2 include but are not limited to:

[0019]

[0020] Furthermore, in the nitrile substance having the structure Y-(CH2)n-CN, Y includes at least one of vinyl, propenyl, allyl, methylvinyl, ethynyl, propynyl, -CN, -COOH, -CHO, and -OH, and n is an integer of 0-5.

[0021] Preferably, in the nitrile substance having the structure of Y-(CH2)n-CN, Y includes any one of methylvinyl, propenyl, allyl, and -CN, and n is 0, 1, 2 or 3.

[0022] In one embodiment, the nitrile substances having the structure of Y-(CH2)n-CN include but are not limited to:

[0023]

[0024] Furthermore, the aromatic aldehyde substance includes at least one of phenylacetaldehyde, benzaldehyde, and o-hydroxybenzaldehyde.

[0025] Furthermore, the precursor material is a silicon-based precursor and / or a metal-organic precursor; the metal-organic precursor includes but is not limited to at least one of a metal precursor of an amino ligand, a metal precursor of a cyclopentadienyl ligand, a metal precursor of an amidine ligand, a metal precursor of a β-diketone ligand, and a halogen metal precursor.

[0026] Furthermore, the semiconductor film is a silicon-containing film or a metal oxide film; the silicon-containing film includes but is not limited to any one of SiO2 film, SiN film, SiC film, SiCN film, SiCNO film, and metal-Si film; the metal oxide film includes but is not limited to any one of metal oxide film, nitride film, carbide film, and metal film.

[0027] In one embodiment, the semiconductor films that can be listed include but are not limited to: HfO2 (hafnium oxide) film, ZrO2 (zirconium oxide) film, Nb2O5 (niobium oxide) film, TiO2 (titanium oxide) film, SrO (strontium oxide) film, BaO (barium oxide) film, W2O3 (tungsten oxide) film, Ta2O5 (tantalum oxide) film, La2O3 (lanthanum oxide); TiN (titanium nitride) film, TaN (tantalum nitride) film, WN (tungsten nitride) film, NbN (niobium nitride) film; Cu (copper) film, Co (cobalt) film, Ni (nickel) film, Ru (ruthenium) film, Pt (platinum) film, Ir (iridium) film, W (tungsten) film.

[0028] Furthermore, the precursor material and the deposition aid material are introduced simultaneously for deposition.

[0029] Alternatively, the deposition is performed in the order of precursor material first and deposition aid material later.

[0030] Furthermore, the inert gas is any one of nitrogen, argon and helium;

[0031] and / or, the co-reactant is any one of an oxidizing material or a reducing material;

[0032] The oxidizing materials include O3, H2O2, H2O, O2, and N2O.

[0033] Reducing materials include H2, NH3, hydrazines and their derivatives.

[0034] Specifically, a method for atomic layer deposition of a semiconductor thin film includes the following steps:

[0035] Step 1: Place the substrate in a reaction chamber and heat it to 50-500°C;

[0036] Step 2: introducing a precursor material and a deposition aid material into the reaction chamber in a pulsed form for deposition; wherein the precursor material is heated to 80-200° C. and then pulsed, the duration of a single pulse is 0.05-20 s, and the duration of a single pulse of the deposition aid material is 0.05-20 s;

[0037] Step 3: Fill the reaction chamber with inert gas for purging to purge the remaining precursor material, deposition aid material and reaction by-products;

[0038] Step 4: introducing a co-reactant into the reaction chamber in a pulsed form, wherein the co-reactant has a flow rate of 5-500 sccm and a pulse time of 0.1-10 s, and reacts with the precursor material chemically adsorbed on the surface of the substrate;

[0039] Step 5, filling with inert gas to purge again, to purge the remaining co-reactant and reaction by-products;

[0040] Steps 2 to 5 are repeated as a cycle to deposit a semiconductor film of a specific thickness.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] 1. The present invention provides an atomic layer deposition method for semiconductor thin films. Compared with the traditional ALD deposition method, the present invention can make the precursor uniformly adsorbed on the substrate, thereby solving the problem of uniformity of the thin film; it can also desorb the side reaction products from the substrate, thereby solving the problem of impurity content in the thin film.

[0043] 2. In one practicable case of the present invention, the precursor material and the deposition aid material are simultaneously introduced into the reaction chamber for reaction, wherein the deposition aid material can quickly carry the precursor molecules to various positions of the wafer, prevent the precursor from agglomerating in local areas, and improve the uniformity of the film thickness to a certain extent. At the same time, the deposition aid material can help the side reaction products to quickly separate from the substrate, reduce impurities in the film, and improve the film quality of the film.

[0044] 3. In another achievable situation of the present invention, the precursor material and the deposition aid material are introduced into the reaction chamber in sequence in the order of the precursor material first and the deposition aid material later. The deposition aid material can redistribute the position distribution of the precursor on the substrate and inhibit the polymerization reaction of the precursor on the substrate, resulting in high impurity content and uneven thickness in some areas. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The present invention will be further described below in conjunction with the accompanying drawings.

[0046] Figure 1 It is a flow chart of an atomic layer deposition method of a semiconductor thin film according to the present invention;

[0047] Figure 2 This is a schematic diagram of ALD deposition in which a precursor material and a deposition aid material are simultaneously introduced into a reaction chamber according to the present invention;

[0048] Figure 3 This is a schematic diagram of conventional ALD deposition without the introduction of deposition aid materials into the reaction chamber;

[0049] Figure 4 It is a schematic diagram of ALD deposition in which a precursor material and a deposition aid material are introduced into a reaction chamber in sequence according to the present invention.

[0050] Figure 2-Figure 4 Here, precursor pluse refers to the pulsed introduction of precursor material, Purge refers to the inert gas purging, auxiliary material pluse refers to the pulsed introduction of deposition auxiliary material, and co-reactant pluse refers to the pulsed introduction of co-reactant. DETAILED DESCRIPTION

[0051] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0052] The deposition method flow chart in the following embodiment is as follows Figure 1 shown.

[0053] In the following embodiments and comparative examples, the film thickness is measured by an ellipsometer, the film thickness is measured at 9 points on an 8-inch wafer, and the uniformity of the film within the 8-inch range is calculated. The uniformity calculation formula is: (standard deviation / average value)×100%;

[0054] The chemical composition of the films was determined by X-ray photoelectron spectroscopy (XPS).

[0055] Example 1

[0056] A method for atomic layer deposition of semiconductor thin films, see Figure 2 The deposition schematic diagram shown includes the following steps:

[0057] Step 1: Place an 8-inch silicon wafer substrate in a reaction chamber and heat the reaction chamber to a temperature of 350°C;

[0058] Step 2, the precursor CpHf(NMe2)3 is loaded into the stainless steel source bottle 1 connected to the reaction chamber through the ALD valve and pipeline, and the source bottle is heated to 90°C; the deposition aid ethylene glycol dimethyl ether is loaded into the stainless steel source bottle 2 connected to the reaction chamber through the ALD valve and pipeline;

[0059] The precursor CpHf(NMe2)3 and the deposition aid ethylene glycol dimethyl ether are introduced into the reaction chamber simultaneously in a pulse form, wherein the duration of a single pulse of the precursor CpHf(NMe2)3 is 2 s, and the duration of a single pulse of the deposition aid ethylene glycol dimethyl ether is 1 s;

[0060] The precursor CpHf(NMe2)3 is uniformly adsorbed on the silicon wafer in the form of chemical adsorption;

[0061] Step 3, filling the reaction chamber with Ar gas for purging to purge the remaining precursor material, deposition aid material and reaction by-products;

[0062] Step 4, introducing O3 into the reaction chamber in a pulsed form, the flow rate of O3 is 80 sccm, the pulse time is 5 s, and reacts with the precursor material chemically adsorbed on the surface of the substrate;

[0063] Step 5, fill with Ar gas and purge again to purge the remaining O3 and reaction by-products;

[0064] Step 2 to step 5 are repeated 100 times as a cycle to obtain a semiconductor film with a specific thickness.

[0065] Comparative Example 1-1

[0066] A method for atomic layer deposition of a semiconductor thin film, which differs from Example 1 in that only the deposition aid ethylene glycol dimethyl ether is replaced by ethyl ether, and the other steps and parameters remain the same.

[0067] Comparative Example 1-2

[0068] A method for atomic layer deposition of semiconductor thin films, see Figure 3 The deposition schematic diagram shown includes the following steps:

[0069] Step 1: Place an 8-inch silicon wafer substrate in a reaction chamber and heat it to 350°C;

[0070] Step 2, the precursor CpHf(NMe2)3 is loaded into a stainless steel source bottle 1 connected to the reaction chamber through an ALD valve and a pipeline, and the source bottle is heated to 90°C;

[0071] The precursor CpHf(NMe2)3 is introduced into the reaction chamber in pulse form. The duration of a single pulse of the precursor CpHf(NMe2)3 is 2s.

[0072] The precursor CpHf(NMe2)3 is uniformly adsorbed on the silicon wafer in the form of chemical adsorption;

[0073] Step 3, filling the reaction chamber with Ar gas for purging to purge the remaining precursor CpHf(NMe2)3 and reaction by-products;

[0074] Step 4: O3 is introduced into the reaction chamber in a pulsed form, the flow rate of O3 is 80 sccm, and the pulse time is 5 s, to react with the precursor CpHf(NMe2)3 chemically adsorbed on the surface of the substrate;

[0075] Step 5, fill with Ar gas and purge again to purge the remaining O3 and reaction by-products;

[0076] Step 2 to step 5 are repeated 100 times as a cycle to obtain a semiconductor film with a specific thickness.

[0077] The film thickness measurement and element composition test results of the semiconductor films deposited in Example 1 and Comparative Examples 1-1 and 1-2 are shown in Table 1:

[0078] Table 1

[0079]

[0080] Example 2

[0081] A method for atomic layer deposition of semiconductor thin films, see Figure 2 The deposition schematic diagram shown includes the following steps:

[0082] Step 1: Place an 8-inch silicon wafer substrate in a reaction chamber and heat it to 250°C;

[0083] Step 2, the precursor CpZr(NMe2)3 is loaded into the stainless steel source bottle 1 connected to the reaction chamber through the ALD valve and pipeline, and the source bottle is heated to 85°C; the deposition aid dimethyl ether is loaded into the stainless steel source bottle 2 connected to the reaction chamber through the ALD valve and pipeline;

[0084] The precursor CpZr(NMe2)3 and the deposition aid o-phenylenedimethyl ether are introduced into the reaction chamber simultaneously in a pulse form, wherein the duration of a single pulse of the precursor CpZr(NMe2)3 is 2 s, and the duration of a single pulse of the deposition aid o-phenylenedimethyl ether is 2 s;

[0085] The precursor CpZr(NMe2)3 is uniformly adsorbed on the silicon wafer in the form of chemical adsorption;

[0086] Step 3, filling the reaction chamber with Ar gas for purging, and purging the residual precursor CpZr(NMe2)3 and deposition aid o-phenyl dimethyl ether and reaction by-products;

[0087] Step 4, introducing O3 into the reaction chamber in a pulsed form, the flow rate of O3 is 100 sccm, the pulse time is 5 s, and reacts with the precursor CpZr(NMe2)3 chemically adsorbed on the surface of the substrate;

[0088] Step 5, fill with Ar gas for purging again to purge the remaining O3 and reaction by-products;

[0089] Step 2 to step 5 are repeated 100 times as a cycle to obtain a semiconductor film with a specific thickness.

[0090] Comparative Example 2

[0091] A method for atomic layer deposition of a semiconductor thin film, which differs from Example 2 in that only the deposition aid o-phenyl dimethyl ether is replaced by methyl phenyl ether, and the other steps and parameters remain the same.

[0092] The film thickness measurement and element composition test results of the semiconductor films deposited in Example 2 and Comparative Example 2 are shown in Table 2:

[0093] Table 2

[0094]

[0095] Example 3

[0096] A method for atomic layer deposition of semiconductor thin films, see Figure 4 The deposition schematic diagram shown includes the following steps:

[0097] Step 1: Place an 8-inch silicon wafer substrate in a reaction chamber and heat it to 230°C;

[0098] Step 2: Precursor La( i PrCp)3 is loaded into a stainless steel source bottle 1 connected to the reaction chamber through an ALD valve and a pipeline, and the source bottle is heated to 135°C; methacrylonitrile, a deposition aid, is loaded into a stainless steel source bottle 2 connected to the reaction chamber through an ALD valve and a pipeline;

[0099] In pulse form, the precursor La( i PrCp)3, single pulse duration is 3s, precursor La( i PrCp)3 is uniformly adsorbed on the silicon wafer in the form of chemical adsorption; Ar gas is introduced to remove the residual precursor La( i PrCp)3 and reaction by-products are purged clean;

[0100] Then, methacrylonitrile, a deposition aid, is introduced into the reaction chamber, and the duration of a single pulse is 1 s;

[0101] Step 3, filling the reaction chamber with Ar gas for purging to purge the residual deposition aid methacrylonitrile;

[0102] Step 4: O3 is introduced into the reaction chamber in a pulsed form. The flow rate of O3 is 150 sccm and the pulse time is 8 s. The precursor La( i PrCp)3 to react;

[0103] Step 5, fill with Ar gas for purging again to purge the remaining O3 and reaction by-products;

[0104] Step 2 to step 5 are repeated 100 times as a cycle to obtain a semiconductor film with a specific thickness.

[0105] Comparative Example 3

[0106] A method for atomic layer deposition of a semiconductor thin film, which differs from Example 3 in that only the deposition aid methacrylonitrile is replaced by acrylonitrile, and the other steps and parameters remain the same.

[0107] The film thickness measurement and element composition test results of the semiconductor films deposited in Example 3 and Comparative Example 3 are shown in Table 3:

[0108] Table 3

[0109]

[0110] Example 4

[0111] A method for atomic layer deposition of semiconductor thin films, see Figure 4 The deposition schematic diagram shown includes the following steps:

[0112] Step 1: Place an 8-inch silicon wafer substrate in a reaction chamber and heat it to 400°C;

[0113] Step 2: Precursor Sr( i PrCp)3 is loaded into a stainless steel source bottle 1 connected to the reaction chamber through an ALD valve and pipeline, and the source bottle is heated to 150°C; the deposition aid phenylacetaldehyde is loaded into a stainless steel source bottle 2 connected to the reaction chamber through an ALD valve and pipeline;

[0114] The precursor Sr( i PrCp)3, the single pulse duration is 2s, the precursor Sr( i PrCp)3 is uniformly adsorbed on the silicon wafer in the form of chemical adsorption; Ar gas is introduced to remove the residual precursor Sr( i PrCp)3 and reaction by-products are purged clean;

[0115] Then, a deposition aid, phenylacetaldehyde, was introduced into the reaction chamber, and the duration of a single pulse was 2 s;

[0116] Step 3, filling the reaction chamber with Ar gas for purging to purge the residual deposition aid phenylacetaldehyde;

[0117] Step 4: H2O is introduced into the reaction chamber in a pulsed form. The H2O pulse time is 1 s, and the precursor Sr( i PrCp)3 to react;

[0118] Step 5: Fill with Ar gas and purge again to purge the remaining H2O and reaction by-products;

[0119] Step 2 to step 5 are repeated 100 times as a cycle to obtain a semiconductor film with a specific thickness.

[0120] Comparative Example 4

[0121] A method for atomic layer deposition of a semiconductor thin film, which differs from Example 4 in that only the deposition aid phenylacetaldehyde is replaced by butyraldehyde, and the other steps and parameters remain the same.

[0122] The film thickness measurement and element composition test results of the semiconductor films deposited in Example 4 and Comparative Example 4 are shown in Table 4:

[0123] Table 4

[0124]

[0125]

[0126] Example 5

[0127] A method for atomic layer deposition of semiconductor thin films, see Figure 4 The deposition schematic diagram shown includes the following steps:

[0128] Step 1: Place an 8-inch silicon wafer substrate in a reaction chamber and heat it to 250°C;

[0129] Step 2: Precursor CpNb(N t Bu)(NMe2)2 is loaded into a stainless steel source bottle 1 connected to the reaction chamber through an ALD valve and pipeline, and the source bottle is heated to 80°C; the deposition aid ethynylpyridine is loaded into a stainless steel source bottle 2 connected to the reaction chamber through an ALD valve and pipeline;

[0130] The precursor CpNb(N t Bu)(NMe2)2, single pulse duration is 3s, precursor CpNb(N tBu)(NMe2)2 is uniformly adsorbed on the silicon wafer in the form of chemical adsorption; Ar gas is introduced to remove the residual precursor CpNb(N t Bu)(NMe2)2 and reaction by-products are purged clean;

[0131] Then, a deposition aid, ethynylpyridine, is introduced into the reaction chamber, and the duration of a single pulse is 1 s;

[0132] Step 3, filling the reaction chamber with Ar gas for purging to purge the residual deposition aid ethynylpyridine;

[0133] Step 4: O3 is introduced into the reaction chamber in a pulsed form. The flow rate of O3 is 150 sccm and the pulse time is 10 s. The precursor CpNb (N t Bu)(NMe2)2 reacts;

[0134] Step 5, fill with Ar gas for purging again to purge the remaining O3 and reaction by-products;

[0135] Step 2 to step 5 are repeated 100 times as a cycle to obtain a semiconductor film with a specific thickness.

[0136] Comparative Example 5

[0137] A method for atomic layer deposition of semiconductor thin films, see Figure 3 The deposition schematic diagram shown includes the following steps:

[0138] Step 1: Place an 8-inch silicon wafer substrate in a reaction chamber and heat it to 250°C;

[0139] Step 2: Precursor CpNb(N t Bu)(NMe2)2 is loaded into a stainless steel source bottle 1 connected to the reaction chamber through an ALD valve and pipeline, and the source bottle is heated to 80°C;

[0140] The precursor CpNb(N t Bu)(NMe2)2, single pulse duration is 3s, precursor CpNb(N t Bu)(NMe2)2 is uniformly adsorbed on the silicon wafer in the form of chemical adsorption;

[0141] Step 3: Fill the reaction chamber with Ar gas for purging to remove the remaining precursor CpNb(N t Bu)(NMe2)2 and reaction by-products are purged clean;

[0142] Step 4: O3 is introduced into the reaction chamber in a pulsed form. The flow rate of O3 is 150 sccm and the pulse time is 10 s. The precursor CpNb (Nt Bu)(NMe2)2 reacts;

[0143] Step 5, fill with Ar gas for purging again to purge the remaining O3 and reaction by-products;

[0144] Step 2 to step 5 are repeated 100 times as a cycle to obtain a semiconductor film with a specific thickness.

[0145] The film thickness measurement and element composition test results of the semiconductor films deposited in Example 5 and Comparative Example 5 are shown in Table 5:

[0146] Table 5

[0147]

[0148]

[0149] Example 6

[0150] A method for atomic layer deposition of semiconductor thin films, see Figure 4 The deposition schematic diagram shown includes the following steps:

[0151] Step 1: Place an 8-inch silicon wafer substrate in a reaction chamber and heat it to 360°C;

[0152] Step 2, the precursor Ti(CpMe5)(OMe)3 is loaded into the stainless steel source bottle 1 connected to the reaction chamber through the ALD valve and pipeline, and the source bottle is heated to 90°C; the deposition aid malononitrile is loaded into the stainless steel source bottle 2 connected to the reaction chamber through the ALD valve and pipeline;

[0153] The precursor Ti(CpMe5)(OMe)3 is first introduced into the reaction chamber in a pulsed form, with a single pulse duration of 1 second. The precursor Ti(CpMe5)(OMe)3 is uniformly adsorbed on the silicon wafer in the form of chemical adsorption; Ar gas is introduced to purge the residual precursor Ti(CpMe5)(OMe)3 and reaction by-products;

[0154] Then, a deposition aid, malononitrile, is introduced into the reaction chamber, and the duration of a single pulse is 4 s;

[0155] Step 3, filling the reaction chamber with Ar gas for purging to purge the residual deposition aid malononitrile;

[0156] Step 4: O3 is introduced into the reaction chamber in a pulsed form, the flow rate of O3 is 200 sccm, and the pulse time is 5 s, to react with the precursor Ti(CpMe5)(OMe)3 chemically adsorbed on the surface of the substrate;

[0157] Step 5, fill with Ar gas for purging again to purge the remaining O3 and reaction by-products;

[0158] Step 2 to step 5 are repeated 200 times as a cycle to obtain a semiconductor film with a specific thickness.

[0159] Comparative Example 6

[0160] A method for atomic layer deposition of semiconductor thin films, see Figure 3 The deposition schematic diagram shown includes the following steps:

[0161] Step 1: Place an 8-inch silicon wafer substrate in a reaction chamber and heat it to 360°C;

[0162] Step 2, the precursor Ti(CpMe5)(OMe)3 is loaded into a stainless steel source bottle 1 connected to the reaction chamber through an ALD valve and pipeline, and the source bottle is heated to 90°C;

[0163] The precursor Ti(CpMe5)(OMe)3 is first introduced into the reaction chamber in a pulse form, and the duration of a single pulse is 1 s. The precursor Ti(CpMe5)(OMe)3 is uniformly adsorbed on the silicon wafer in the form of chemical adsorption;

[0164] Step 3, filling the reaction chamber with Ar gas for purging to purge the residual precursor Ti(CpMe5)(OMe)3 and reaction by-products;

[0165] Step 4: O3 is introduced into the reaction chamber in a pulsed form, the flow rate of O3 is 200 sccm, and the pulse time is 5 s, to react with the precursor Ti(CpMe5)(OMe)3 chemically adsorbed on the surface of the substrate;

[0166] Step 5, fill with Ar gas for purging again to purge the remaining O3 and reaction by-products;

[0167] Step 2 to step 5 are repeated 200 times as a cycle to obtain a semiconductor film with a specific thickness.

[0168] The film thickness measurement and element composition test results of the semiconductor films deposited in Example 6 and Comparative Example 6 are shown in Table 6:

[0169] Table 6

[0170]

[0171] By comparing the above embodiments and comparative examples, it can be seen that: (1) Compared with the traditional ALD deposition method, the use of the deposition aid material in the present application can significantly improve the film quality of the ALD film, and improve the uniformity and purity of the film thickness. (2) Different deposition aid materials have many differences in chemical properties and structures. After combining with the precursor or substrate surface, they have different effects on the chemical activity of the deposition surface, the saturation process of the precursor / co-reactant, etc. Only by selecting a suitable deposition aid can a better effect of improving the film quality be achieved.

[0172] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0173] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for atomic layer deposition of semiconductor thin films, characterized in that: The following steps are involved: Precursor materials and deposition aid materials are introduced to deposit on the substrate, and after inert gas is purged, a co-reactant is introduced and the inert gas is purged again; the cycle is repeated several times to deposit a semiconductor film; The deposition aid material comprises at least one of the following substances: (1) Ether substances of the structure R1O-X-OR2, wherein R1 and R2 are independently selected from methyl or ethyl, and X is one or a group of C2-C5 alkyl, phenyl, carbonyl, C2-C6 alkenyl; (2) The structure is Y-(CH2) n -CN nitrile substances, wherein Y is an unsaturated group and n is an integer of 0-5; (3) Aromatic aldehydes; (4) Pyridine and its alkynyl derivatives.

2. The method for atomic layer deposition of a semiconductor thin film according to claim 1, characterized in that: The chemical structural formula of the pyridine and its alkynyl derivatives is Formula 1: Any one of x, y, and z is The rest are -H, and n is any integer ≥0.

3. The method for atomic layer deposition of a semiconductor thin film according to claim 1, characterized in that: In the ether substance with the structure of R1O-X-OR2, R1 and R2 are independently selected from methyl or ethyl, and X is one or a group of C2-C5 alkyl, phenyl.

4. The method for atomic layer deposition of a semiconductor thin film according to claim 1, characterized in that: The structure is Y-(CH2) n In the nitrile substances of -CN, Y includes at least one of vinyl, propenyl, allyl, methylvinyl, ethynyl, propynyl, -CN, -COOH, -CHO, and -OH, and n is an integer of 0-5.

5. The method for atomic layer deposition of a semiconductor thin film according to claim 3, characterized in that: The ether substance with the structure of R1O-X-OR2 includes at least one of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, propylene glycol dimethyl ether, o-phenylene dimethyl ether, p-phenylene dimethyl ether and o-phenylene diethyl ether.

6. The method for atomic layer deposition of a semiconductor thin film according to claim 4, characterized in that: The structure is Y-(CH2) n In the nitrile substance of -CN, Y includes any one of methylvinyl, propenyl, allyl, and -CN, and n is 0, 1, 2 or 3.

7. The method for atomic layer deposition of a semiconductor thin film according to claim 1, characterized in that: The aromatic aldehyde substances include at least one of phenylacetaldehyde, benzaldehyde and o-hydroxybenzaldehyde.

8. The method for atomic layer deposition of a semiconductor thin film according to any one of claims 1 to 7, characterized in that: The semiconductor film is a silicon-containing film or a metal oxide film. The silicon-containing film includes but is not limited to any one of SiO2 film, SiN film, SiC film, SiCN film, SiCNO film, and metal-Si film; the metal oxide film includes but is not limited to any one of metal oxide film, nitride film, carbide film, and metal film.

9. The method for atomic layer deposition of a semiconductor thin film according to any one of claims 1 to 7, characterized in that: Precursor materials and deposition aid materials are introduced simultaneously for deposition; Alternatively, the deposition is carried out in the order of precursor material first and deposition aid material later.

10. The method for atomic layer deposition of a semiconductor thin film according to claim 1, characterized in that: The inert gas is any one of nitrogen, argon and helium; And / or, the co-reactant is any one of an oxidizing material or a reducing material, the oxidizing material includes O3, H2O2, H2O, O2, N2O, and the reducing material includes H2, NH3, hydrazines and their derivatives.

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