Method of selective deposition for forming fully self-aligned vias

Abstract

Methods are provided for selective film deposition. One method includes providing a substrate containing a dielectric material and a metal layer, the metal layer having an oxidized metal layer thereon, coating the substrate with a metal-containing catalyst layer, treating the substrate with an alcohol solution that removes the oxidized metal layer from the metal layer along with the metal-containing catalyst layer on the oxidized metal layer, and exposing the substrate to a process gas containing a silanol gas for a time period that selectively deposits a SiO 2film on the metal-containing catalyst layer on the dielectric material.

Description

[Technical Field]

[0001] Cross-reference to related applications: This application relates to and claims priority to the following application: U.S. Provisional Patent Application No. 62 / 588,855, filed November 20, 2017, the entire contents of which are incorporated herein by reference. This application relates to and claims priority to the following application: U.S. Provisional Patent Application No. 62 / 685,847, filed June 15, 2018, the entire contents of which are incorporated herein by reference.

[0002] This invention relates to semiconductor manufacturing processes and semiconductor devices, and more particularly to a method for selectively depositing thin films using surface pretreatment. [Previous Technology]

[0003] As device dimensions shrink, the complexity of semiconductor device manufacturing increases. The cost of manufacturing semiconductor devices also rises, necessitating cost-effective solutions and innovations. With the manufacture of smaller transistors, producing the critical dimension (CD) or resolution of patterned features becomes increasingly challenging. At highly miniaturized technology nodes, selective deposition of thin films is a key step in patterning. New deposition methods are needed to provide selective thin film deposition on surfaces of different materials. [Summary of the Invention]

[0004] A specific embodiment of the present invention provides a method for selectively depositing thin films using a surface pretreatment.

[0005] According to a specific embodiment, the method includes: providing a substrate, wherein the substrate includes a dielectric material and a metal layer, and the metal layer has a metal oxide layer thereon; coating the substrate with a metal catalyst layer; treating the substrate with an alcohol solution to remove the metal oxide layer together with the metal catalyst layer thereon from the metal layer; and exposing the substrate to a process gas containing a silanol gas for a period of time to selectively deposit a SiO2 thin film on the metal catalyst layer located on the dielectric material.

[0006] According to another specific embodiment of the present invention, the method includes: providing a substrate, wherein the substrate includes a dielectric material and a metal layer, and the metal layer has a metal oxide layer thereon; exposing the substrate to a reactive gas, the reactive gas containing molecules forming self-assembled monolayers (SAMs) on the substrate; selectively depositing a metal oxide film on the dielectric material relative to the metal oxide layer by exposing the substrate to a deposition gas; and exposing the substrate to a process gas containing a silanol gas for a period of time to selectively deposit a silicon oxide (SiO2) film on the metal oxide film.

[0007] According to another specific embodiment, the method includes: providing a substrate, wherein the substrate includes a dielectric material and a metal layer, and the metal layer has a metal oxide layer thereon; exposing the substrate to hydrogen gas excited by a plasma source; selectively depositing a metal oxide film on the dielectric material by exposing the substrate to a deposition gas; and exposing the substrate to a process gas containing silanol gas for a period of time to selectively deposit a SiO2 thin film on the metal oxide film.

Implementation Method

[0012] Specific embodiments of the invention provide an effective surface pretreatment method for selectively depositing silicon dioxide films and dielectric laminates on dielectric materials relative to metal layers.

[0013] Figures 1A to 1D show, through schematic cross-sectional views, a method for selectively depositing a SiO2 thin film on a substrate according to a specific embodiment of the present invention. In Figure 1A, the patterned substrate 1 includes a dielectric material 100, a dielectric material 101 on the dielectric material 100, a metal layer 104 embedded in the dielectric material 100, a metal oxide layer 107 on the metal layer 104, and a diffusion barrier layer 102 separating the metal layer 104 from the dielectric material 100. For example, the metal layer 104 may include copper (Cu), ruthenium (Ru), cobalt (Co), or tungsten (W). For example, the metal oxide layer 107 may include oxidized copper, oxidized ruthenium, oxidized cobalt, or oxidized tungsten. For example, the dielectric material 100 may include a low-k dielectric material, SiO2, or a metal-containing dielectric material. For example, the metal-containing dielectric material may comprise a metal oxide, a metal nitride, or a metal oxynitride. In some examples, the diffusion barrier layer 102 may comprise TaN, TiN, TaSiN, or TiSiN. The dielectric material 101, as depicted in FIG1A, may be used as an etch stop layer in a chemical mechanical planarization (CMP) process for planarizing the substrate 1. The dielectric material 101 may comprise SiCN or SiOC. In one example, the dielectric material 101 may comprise the same material as the dielectric material 100. The metal oxide layer 107 may be formed by exposing the metal layer 104 to an oxygen-containing gas during the substrate fabrication process, including exposure to O2 and H2O in the background gas or process gas of the process system. In one example, the metal oxide layer 107 may be formed during or after the CMP process. In one example, the metal oxide layer 107 may have an open region that is not complete, exposing the metal layer 104.

[0014] According to a specific embodiment of the present invention, a method is provided for selectively depositing a SiO2 thin film on a dielectric material 101 relative to the metal oxide layer 107 or the metal layer 104. The metal oxide layer 107 can affect the deposition of the selective SiO2 thin film by reducing the deposition selectivity. Therefore, a substrate pretreatment is provided to effectively remove the metal oxide layer 107 from the metal layer 104, wherein the substrate pretreatment can be integrated into a selective SiO2 thin film deposition method to form fully self-aligned dielectric windows and other recessed features.

[0015] According to one embodiment, the substrate 1 in FIG. 1A is coated with a metal catalyst layer 105. As shown in schematic diagram 1B, the areal density of the metal catalyst layer 105 (the "X"-shaped portion in the figure) on the metal oxide layer 107 may be lower than that on the dielectric material 100. According to some embodiments of the present invention, the metal catalyst layer 105 may comprise aluminum (Al), titanium (Ti), or both aluminum and titanium. The metal catalyst layer 105 may be selected from the group consisting of Al, Al₂O₃, AlN, AlON, an aluminum-containing precursor, an aluminum-containing alloy, CuAl, TiAlN, TaAlN, Ti, TiAlC, TiO₂, TiON, TiN, a titanium-containing precursor, a titanium-containing alloy, and combinations thereof. The metal catalyst layer 105 may be formed by exposing the substrate 1 to a metal precursor vapor and optionally an oxygen-containing gas and / or a nitrogen-containing gas. This exposure step can be performed as follows: by exposing the substrate 1 to a pulse of metal-containing gas, the metal-containing gas pulse can adsorb a metal-containing catalyst layer 105 approximately one monolayer thick. In one example, the metal-containing catalyst layer 105 may contain a layer of adsorbed metal-containing precursor, such as AlMe3.

[0016] Specific embodiments of the present invention can utilize a wide range of aluminum-containing precursors. For example, many aluminum precursors have the following chemical formula: AlL1L2L3Dx, where L1, L2, and L3 are individual anionic ligands, and D is a neutral precursor ligand, where x can be 0, 1, or 2. Each L1, L2, and L3 ligand can be individually selected from the group consisting of alkoxides, halides, aryloxides, amides, cyclopentadienyls, alkyls, silyls, amidinates, β-diketonates, ketoiminates, silanoates, and carboxylates. The D ligand can be selected from the group consisting of free ethers, furans, pyridines, pyrroles, pyrrolidines, amines, crown ethers, glymes, and nitriles.

[0017] Other examples of aluminum precursors include: AlMe 3, AlEt 3, AlMe 2H, [Al(O sBu) 3] 4, Al(CH 3COCHCOCH 3) 3, AlCl 3, AlBr 3, AlI 3, Al(O iPr) 3, [Al(NMe 2) 3] 2, Al( iBu) 2Cl, Al( iBu) 3, Al( iBu) 2H, AlEt 2Cl, Et 3Al 2(O sBu) 3, and Al(THD) 3.

[0018] Specific embodiments of the present invention can utilize a wide range of titanium-containing precursors. Examples include titanium-containing precursors having "Ti-N" intramolecular bonds, including Ti(NEt 2) 4 (TDEAT), Ti(NMeEt) 4 (TEMAT), and Ti(NMe 2) 4 (TDMAT). Other examples of titanium-containing precursors include those with an intramolecular "Ti-C" bond, including Ti(COCH3)(η5-C5H5)2Cl, Ti(η5-C5H5)Cl2, Ti(η5-C5H5)Cl3, Ti(η5-C5H5)2Cl2, Ti(η5-C5(CH3)5)Cl3, Ti(CH3)(η5-C5H5)2Cl, Ti(η5-C9H7)2Cl2, Ti((η5-C5(CH3)5)2Cl, Ti((η5-C5(CH3)5)2Cl2, Ti(η5-C5H5)2(μ-Cl)2, and Ti(η5-C5H5)2(μ-Cl). 2(CO) 2、Ti(CH 3) 3(η 5-C 5H 5) 、Ti(CH 3) 2(η 5-C 5H 5) 2、Ti(CH 3) 4、Ti(η 5-C 5H 5)(η 7-C 7H 7) 、Ti(η 5-C 5H 5)(η 8-C 8H 8) . 5) 2. And TiCl Examples 4 are titanium halide precursors with "titanium-halogen" bonds.

[0019] This process further includes treating the substrate 1 in FIG. 1B with an alcohol solution, the alcohol solution removing the oxide metal layer 107 and the metal-containing catalyst layer 105 from the metal layer 104. The above is illustrated in FIG. 1C, where the metal-containing catalyst layer 105 remains only on the dielectric material 101. The inventors have discovered that contacting the substrate 1 with an alcohol solution effectively peels off the oxide metal layer 107 without re-oxidizing the underlying metal layer 104, and since the metal-containing catalyst layer 105 is connected to the removed oxide metal layer 107, the metal-containing catalyst layer 105 is also removed during the peeling process. In one example, the alcohol solution can contact the substrate 1 at room temperature. The alcohol solution may consist of one or more alcohols, or it may consist of one or more alcohols and a non-oxidizing solvent. The alcohol solution may contain any alcohol having the chemical formula "R-OH". One type of alcohol is the primary alcohol, with methanol and ethanol being the simplest members. Another type of alcohol is the secondary alcohol, such as isopropanol (IPA).

[0020] This process method further includes exposing the substrate 1 to a process gas containing silanol for a period of time, such that a SiO2 thin film 106 is selectively deposited on the metal catalyst layer 105 in a self-limiting manner on the dielectric material 101 but not on the metal layer 104. The above is schematically shown in FIG1D.

[0021] The metal catalyst layer 105 catalyzes the selective deposition of the SiO2 thin film 106 from the silanol gas, and this catalytic effect can be observed until the thickness of the deposited SiO2 thin film 106 is about 15 nm or less, and then the SiO2 deposition automatically stops when there are no catalytic sites left on the substrate 1. This exposure to the process gas can be carried out for a period of time without causing significant SiO2 deposition on the metal layer 104. According to a specific embodiment of the invention, the substrate 1 is exposed to the process gas containing the silanol gas in the absence of any oxidant and hydrolysant. In one example, the silanol gas may be selected from the group consisting of tris(tert-pentoxy) silanol, tris(tert-butoxy) silanol, and bis(tert-butoxy)(isopropoxy) silanol.

[0022] The process gas may further include an inert gas such as argon. In one example, the process gas may consist of a silanol gas and an inert gas. During the exposure step, the substrate temperature may be about 150 °C or lower. In another specific embodiment, the substrate temperature may be about 120 °C or lower. In yet another specific embodiment, the substrate temperature may be about 100 °C or lower.

[0023] According to a specific embodiment of the present invention, the steps of coating the substrate 1 with a metal catalyst layer 105, treating the substrate 1 with an alcohol solution to remove the metal catalyst layer 105 from the metal layer 104, and exposing the substrate 1 to a process gas containing silanol gas can be repeated one or more times to increase the thickness of the SiO2 thin film 106. As seen in FIG1D, the SiO2 thin film 106 forms a fully self-aligned interlayer window 112 on the metal layer 104. The fully self-aligned interlayer window 112 may also be referred to as holes or trenches.

[0024] Figures 2A-2E show schematic cross-sectional views of a method for selectively depositing a dielectric multilayer film on a substrate according to a specific embodiment of the present invention. The substrate 1 in Figure 1A has been reproduced as the substrate 2 in Figure 2A. According to a specific embodiment, the substrate 2 in Figure 2A is pretreated by exposure to a reactive gas containing molecules capable of forming self-assembled monolayers (SAMs) on the substrate 2. Figure 2B shows the SAMs 109 (the "Y"-shaped portion) on the metal oxide layer 107. SAMs are molecular assemblies that spontaneously form on the substrate surface through adsorption and are organized into generally large, regular regions. The SAMs may comprise a molecule having a head group, a tail group, and a functional end group, and the SAMs are formed by chemisorbing the head group from the gas phase onto the substrate at room temperature or above room temperature, followed by the slow organization of the tail group. Initially, when the molecular density on the surface is low, the adsorbed molecules either form an irregular molecular mass or a regular two-dimensional "lying down phase," and with a higher molecular coverage, they begin to form a three-dimensional crystalline or semi-crystalline structure on the substrate surface over a period of several minutes to several hours. The head groups are assembled together on the substrate, while the tail groups are assembled away from the substrate.

[0025] According to one specific embodiment, the head group of the molecule forming SAMs may include a thiol, a silane, or a phosphonate. Examples of silane include molecules having C, H, Cl, F, and Si atoms or molecules having C, H, Cl, and Si atoms. Non-limiting examples of this molecule include perfluorodecyltrichlorosilane (CF3(CF2)7CH2CH2SiCl3), perfluorodecanethiol (CF3(CF2)7CH2CH2SH), chlorodecyldimethylsilane (CH3(CH2)8CH2Si(CH3)2Cl), and tertbutyl(chloro)dimethylsilane ((CH3)3CSi(CH3)2Cl).

[0026] The pretreatment of forming the SAMs 109 on a substrate 2 can be used to allow selective deposition of subsequent metal oxides on the dielectric material surface relative to the metal layer surface or the metal oxide layer surface. This selective deposition provides a method for selectively depositing a metal oxide film on the dielectric material surface while preventing or reducing metal oxide deposition on both the metal layer surface and the metal oxide layer surface. It is speculated that the SAM density is higher on the metal oxide layer 107 than on the dielectric material 101, possibly due to the initially higher regularity of the molecules on the metal oxide layer 107.

[0027] Following this pretreatment, a metal oxide film 111 is selectively deposited on the dielectric material 101 relative to the metal oxide layer 107 by exposing the substrate 2 to a deposition gas. This is illustrated in FIG. 2C. In one example, the metal oxide film 111 may contain HfO 2, ZrO 2, or Al 2O 3. For example, the metal oxide film 111 may be deposited by atomic layer deposition (ALD) or plasma-enhanced atomic layer deposition (PEALD). In some examples, the metal oxide film 111 may be deposited by an ALD using an alternating exposure operation of a metal precursor and an oxidant (e.g., H 2O, H 2O 2, plasma-excited O 2 or O 3).

[0028] This process method further includes exposing the substrate 2 to a process gas containing silanol gas for a period of time, so that a SiO2 thin film 113 is selectively deposited on the metal oxide film 111. The above is illustrated in FIG2D. In one example, the effective dielectric constant of the stack containing the metal oxide film 111 and the SiO2 thin film 113 is less than about 7 stack.

[0029] According to a specific embodiment of the present invention, the metal oxide film 111 catalyzes the selective deposition of a SiO2 thin film 113 from a silanol gas, and this catalytic effect can be observed until the thickness of the deposited SiO2 thin film 113 is about 15 nm or less, after which the SiO2 deposition automatically stops. This exposure to the process gas can be carried out for a period of time without resulting in significant SiO2 deposition on the metal oxide layer 107. According to a specific embodiment of the present invention, the substrate 2 is exposed to a process gas containing silanol gas in the absence of any oxidizing agent and hydrolyzing agent. The silanol gas may be selected from the group consisting of tris(tert-pentoxy) silanol, tris(tert-butoxy) silanol, and bis(tert-butoxy)(isopropoxy) silanol.

[0030] In some examples, the process gas may further comprise an inert gas, such as argon. In one specific embodiment, the process gas may consist of a silanol gas and an inert gas. Furthermore, according to one specific embodiment, the substrate temperature may be about 150 °C or lower during the exposure step. In another specific embodiment, the substrate temperature may be about 120 °C or lower. In yet another specific embodiment, the substrate temperature may be about 100 °C or lower.

[0031] Subsequently, the SAMs 109 can be removed from the substrate 2 by heat treatment at a temperature exceeding approximately 300°C, by exposure to plasma-excited hydrogen (H2), by exposure to plasma-excited oxygen (O2), or a combination thereof. As seen in FIG2E, the SiO2 thin film 113 and the metal oxide film 111 form a fully self-aligned interface window 114 on the metal layer 104. The fully self-aligned interface window 114 may also be referred to as a via or trench.

[0032] According to another specific embodiment, the SAM pretreatment can be replaced by a step of exposing the metal oxide layer 107 to hydrogen (H2) excited by a plasma source to form -H terminals (the "Y"-shaped portions in the figure) on the metal oxide layer 107 or the metal layer 104. This is illustrated in Figure 2B. According to one specific embodiment, a chemical oxide removal (COR) process can be performed before the hydrogen exposure step to remove the metal oxide layer 107 from the substrate 2. The COR process includes exposing the substrate 2 to HF gas and NH3 gas and performing a heat treatment step. After the COR process, the hydrogen exposure step forms -H terminals on the metal layer 104. The -H terminals on the metal oxide layer 107 or the metal layer 104 can provide a long nucleation period, during which initially little or no thin film deposition can be observed on these layers. Conversely, on the surface of dielectric material 101 with hydroxyl (-OH) terminals, thin film deposition with little or no nucleation period was observed.

[0033] After the step of exposure to hydrogen (H2) excited by a plasma source, the substrate 2 may be further processed as described above with reference to FIG2C-2D to form a stack containing a SiO2 thin film 113 on a metal oxide film 111. In one example, the metal oxide film 111 may be deposited through an ALD process that is periodically interrupted by the step of exposure to hydrogen (H2) excited by a plasma source to improve the deposition selectivity of the metal oxide film 111 on the dielectric material 101.

[0034] Figure 3 is a schematic diagram of a plasma processing system. According to a specific embodiment of the present invention, the plasma processing system includes an RLSA™ plasma system for pre-treating a substrate with H2 gas. As shown in the figure, the plasma processing system 10 includes a plasma processing chamber 20 (vacuum chamber), an antenna unit 57, and a substrate holder 21. The interior of the plasma processing chamber 20 is roughly divided into: a plasma generation region R1 located below a plasma gas supply unit 30; and a plasma diffusion region R2 on the side of the substrate holder 21. The plasma generated in the plasma generation region R1 may have an electron temperature of several electron volts (eV). When the plasma diffuses into the plasma diffusion region R2 (where the thin film formation process is performed), the electron temperature of the plasma near the substrate holder 21 drops to a value below about 2 eV. The substrate holder 21 is located at the bottom center of the plasma processing chamber 20 and serves as a mounting unit for mounting a substrate W. The substrate holder 21 is provided with an insulating member 21a, a cooling jacket 21b, and a temperature control unit (not shown in this figure) for controlling the substrate temperature.

[0035] The top of the plasma processing chamber 20 is open. The plasma gas supply unit 30 is disposed opposite to the substrate 21 and is sealed together with the top of the plasma processing chamber 20 by a sealing member (e.g., an O-ring) not shown in this figure. The plasma gas supply unit 30, which can also be used as a dielectric window, is made of a material such as alumina or quartz, and has a substantially disc-shaped planar surface facing the substrate 21. A plurality of gas supply holes 31 are disposed opposite to the substrate 21 on the planar surface of the plasma gas supply unit 30. The plurality of gas supply holes 31 are connected to a plasma gas supply port 33 through an airflow channel 32. Plasma gas supply sources 34, 45, 46, and 47 supply plasma gas (such as H2 gas and argon gas) into the plasma gas supply port 33. The plasma gas is then uniformly supplied into the plasma generation region R1 through the plurality of gas supply holes 31.

[0036] The plasma processing system 10 further includes a process gas supply unit 40, which is substantially located at the center of the plasma processing chamber 20, between the plasma generation region R1 and the plasma diffusion region R2. The process gas supply unit 40 is made of a conductive material, such as a magnesium (Mg)-containing aluminum alloy or stainless steel. Like the plasma gas supply unit 30, a plurality of gas supply holes 41 are provided on one of the planar surfaces of the process gas supply unit 40. The planar surface of the process gas supply unit 40 is located relative to the substrate 21 and has a disc shape.

[0037] The plasma processing chamber 20 further includes an exhaust pipe 26 connected to the bottom of the plasma processing chamber 20, and a vacuum line 27 connecting the exhaust pipe to a pressure control valve 28 and a vacuum pump 29. The pressure control valve 28 can be used to achieve a required pressure within the plasma processing chamber 20.

[0038] A plan view of the process gas supply unit 40 is shown in Figure 4. As shown, a grid-like airflow channel 42, also referred to as a spray plate, is formed in the process gas supply unit 40. The grid-like airflow channel 42 is connected to the upper end of a plurality of gas supply holes 41 formed in a vertical direction. The lower end of the plurality of gas supply holes 41 is an opening facing the substrate 21. The plurality of gas supply holes 41 are connected to a process gas supply port 43 through the grid-like airflow channel 42.

[0039] Furthermore, a plurality of openings 44 are formed on the process gas supply unit 40, such that the plurality of openings 44 penetrate the process gas supply unit 40 in the vertical direction. The plurality of openings 44 allow plasma gases, such as H2 gas and optionally argon gas, to pass through and enter the plasma diffusion region R2 located on the side of the substrate 21. As shown in FIG4, the plurality of openings 44 are formed between adjacent gas flow channels 42. For example, the process gas is supplied to the process gas supply port 43 by separate process gas supply sources 45 and 46. According to some specific embodiments, any combination of H2 and Ar may flow through the process gas supply unit 40 and / or through the plasma gas supply port 33. Furthermore, for example, the plurality of openings 44 may occupy an area on the process gas supply unit 40 that extends beyond the peripheral edge of the substrate W.

[0040] The process gas flows through the mesh-like airflow channel 42 and is uniformly supplied into the plasma diffusion region R2 through the multiple gas supply holes 41. The plasma processing system 10 further includes four valves (V1-V4) and four flow controllers (MFC1-MFC4) to control the gas supply entering the plasma processing chamber 20 respectively.

[0041] An external microwave signal generator 55 provides a microwave signal (or microwave energy) at a predetermined frequency (e.g., 2.45 Hz) to the antenna element 57 via a coaxial waveguide 54. The coaxial waveguide 54 may include an inner conductor 54B and an outer conductor 54A. The microwaves from the microwave signal generator 55 generate an electric field in the plasma generation region R1 directly below the plasma gas supply unit 30, which in turn causes the excitation of the process gas in the plasma processing chamber 20.

[0042] Figure 5 shows a partial cross-sectional view of the antenna element 57. As shown, the antenna element 57 may include a flat antenna body 51, a radiating slot plate 52, and a dielectric plate 53 to shorten the microwave wavelength. The flat antenna body 51 has a circular shape with an open bottom surface. The radiating slot plate 52 is formed to close the open bottom surface of the flat antenna body 51. The flat antenna body 51 and the radiating slot plate 52 are made of a conductive material having a flat, hollow, circular waveguide shape.

[0043] A plurality of slots 56 are provided on the radiating slot plate 52 to generate a circularly polarized wave. The plurality of slots 56 are arranged in a generally T-shaped configuration with minute gaps between them, forming a concentric circle pattern or a spiral pattern along a circumferential direction. Since the slots 56a and 56b are perpendicular to each other, a circularly polarized wave containing two orthogonal polarization components is radiated from the radiating slot plate 52 as a plane wave.

[0044] The dielectric plate 53 is made of a low-loss dielectric material such as aluminum oxide (Al₂O₃) or silicon nitride (Si₃N₄), and is disposed between the radiating slot plate 52 and the flat antenna body 51. The radiating slot plate 52 is mounted on the plasma processing chamber 20 using a sealing member (not shown in the figure) so that the radiating slot plate 52 is in close contact with a cover plate 23. The cover plate 23 is located on the upper surface of the plasma gas supply unit 30 and is formed of a microwave-transmitting dielectric material such as aluminum oxide (Al₂O₃).

[0045] An external high-frequency power supply 22 is electrically connected to the base plate 21 via a matching network 25. The external high-frequency power supply 22 generates an RF bias power at a predetermined frequency (e.g., 13.56 MHz) to control the ion energy directed to the substrate W. The power supply 22 is further configured to selectively provide RF bias power pulses with a pulse frequency greater than 1 Hz, such as 2 Hz, 4 Hz, 6 Hz, 8 Hz, 10 Hz, 20 Hz, 30 Hz, 50 Hz, or higher. The power supply 22 is configured to provide RF bias power, which can be between 0 W and 100 W, 100 W and 200 W, 200 W and 300 W, 300 W and 400 W, or 400 W and 500 W. It is worth noting that those skilled in the art will understand that the power level of the power supply 22 is related to the size of the substrate being processed. For example, during the manufacturing process, a 300 mm Si wafer requires more power than a 200 mm wafer. The plasma processing system 10 further includes a DC voltage generator 35, which can provide a DC voltage bias between approximately -5kV and approximately +5kV on the substrate 21.

[0046] During exposure to plasma, plasma gases, such as H2 gas and selectively Ar gas, can be introduced into the plasma processing chamber 20 using the plasma gas supply unit 30. Alternatively, process gases can be introduced into the plasma processing chamber 20 using the process gas supply unit 40.

[0047] Methods for selectively depositing thin films using surface pretreatment have been disclosed in various specific embodiments. The foregoing description of specific embodiments of the invention has been provided for illustrative purposes. This description is not intended to exhaustively detail or limit the invention to the precise form disclosed. The terminology used in this description and in the subsequent claims is for descriptive purposes only and should not be construed as limiting. Those skilled in the art to which this invention pertains will appreciate that many modifications and alterations are possible in light of the foregoing teachings. Those skilled in the art to which this invention pertains will recognize various equivalent combinations and substitutions of the various elements shown in the figures. Therefore, the scope of the invention is not limited by the detailed description, but rather by the claims appended herein. [Simplified Explanation of the Diagram]

[0008] A more complete understanding of the specific embodiments of the invention will be gained by referring to the following detailed description, particularly the section on implementation methods, and by considering them in conjunction with the accompanying drawings, in which many of their accompanying advantages also become apparent, wherein:

[0009] Figures 1A-1D show schematic cross-sectional views illustrating a method for selectively depositing a SiO2 thin film on a substrate according to a specific embodiment of the present invention;

[0010] Figures 2A-2E show, through schematic cross-sectional views, a method for selectively depositing a dielectric multilayer film on a substrate according to a specific embodiment of the present invention; and

[0011] Figures 3-5 are schematic diagrams of a plasma processing system according to a specific embodiment of the present invention. The plasma processing system includes an RLSA™ plasma system for pretreating a substrate with H2 gas.

Claims

1. A substrate fabrication method comprising: providing a substrate comprising a dielectric material, a metal layer, and a metal oxide layer on the metal layer; exposing the substrate to a reactive gas containing molecules forming self-assembled monolayers (SAMs) on the substrate; selectively depositing a metal oxide film on the dielectric material relative to the metal oxide layer by exposing the substrate to a deposition gas; and selectively depositing a SiO2 thin film on the metal oxide film by exposing the substrate to a process gas containing a silanol gas for a period of time.

2. The substrate manufacturing method of claim 1, wherein the metal layer comprises Cu, Ru, Co, or W, and the oxide metal layer comprises copper oxide, ruthenium oxide, cobalt oxide, or tungsten oxide.

3. The substrate manufacturing method of claim 1, wherein the molecule comprises a head group, a tail group, and a functional end group, and wherein the head group comprises a thiol group, a silyl group, or a phosphate group.

4. The substrate manufacturing method of claim 1, wherein the molecule comprises perfluorodecyltrichlorosilane ((CF3(CF2)7CH2CH2SiCl3)), perfluorodecanethiol ((CF3(CF2)7CH2CH2SH)), chlorodecyldimethylsilane ((CH3(CH2)8CH2Si(CH3)2Cl)), or tributyl(chloro)dimethylsilane (((CH3)3CSi(Cl)(CH3)2)).

5. The substrate manufacturing method of claim 1, wherein the metal oxide film comprises HfO 2, ZrO 2, or Al 2O 3.

6. The substrate manufacturing method of claim 1, wherein the step of exposing the substrate to the process gas containing the silanol gas is performed at a substrate temperature of about 150 °C or lower in the absence of any oxidizing agent and hydrolyzing agent.

7. The substrate manufacturing method of claim 1, wherein the silanol gas is selected from the group consisting of triterpenoid silanol, triterpenoid butyroxyl silanol, and bis(terpenoid butyroxyl)isopropoxy silanol.

8. The substrate manufacturing method of claim 1 further includes: repeating the step of exposing the substrate to the reactive gas, the step of selectively depositing the metal oxide film, and the step of exposing the substrate to the process gas containing the silanol gas at least once, to increase the thickness of the metal oxide film and the SiO2 thin film on the dielectric material.

9. The substrate manufacturing method of claim 1, wherein the dielectric material surrounds the metal layer.

10. A substrate fabrication method comprising: providing a substrate comprising a dielectric material, a metal layer, and a metal oxide layer on the metal layer, wherein the metal layer comprises Cu, Ru, Co, or W, and the metal oxide layer comprises copper oxide, ruthenium oxide, cobalt oxide, or tungsten oxide; exposing the substrate to a reactive gas containing molecules forming self-assembled monolayers (SAMs) on the substrate, wherein the molecules comprise head groups, tail groups, and functional end groups, and wherein the head groups comprise thiols, silyl groups, or phosphate groups; selectively depositing a metal oxide film on the dielectric material relative to the metal oxide layer by exposing the substrate to a deposition gas; and selectively depositing SiO2 onto the substrate by exposing the substrate to a process gas containing a silanol gas for a period of time.

2. A thin film is deposited on the metal oxide film; and the steps of exposing the substrate to the reactive gas, selectively depositing the metal oxide film, and exposing the substrate to the process gas containing the silanol gas are repeated at least once to increase the thickness of the metal oxide film and the SiO2 film on the dielectric material.

11. A substrate fabrication method comprising: providing a substrate comprising a dielectric material, a metal layer, and a metal oxide layer on the metal layer; exposing the substrate to hydrogen gas (H2) excited by a plasma source; selectively depositing a metal oxide film on the dielectric material relative to the metal oxide layer by exposing the substrate to a deposition gas; and exposing the substrate to a process gas containing silanol gas for a period of time to selectively deposit a SiO2 thin film on the metal oxide film.

12. The substrate manufacturing method of claim 11, wherein the metal layer comprises Cu, Ru, Co, or W, and the oxide metal layer comprises copper oxide, ruthenium oxide, cobalt oxide, or tungsten oxide.

13. The substrate manufacturing method of claim 11, wherein the step of exposing the substrate to hydrogen gas excited by the plasma source forms a hydrogen terminal (-hydrogen terminal) on the metal oxide layer.

14. The substrate manufacturing method of claim 11 further includes: removing the metal oxide layer from the metal layer; and selectively depositing the metal oxide film on the dielectric material relative to the metal layer by exposing the substrate to the deposition gas.

15. The substrate manufacturing method of claim 11, wherein the removal step includes a chemical oxide removal (COR) process.

16. The substrate manufacturing method of claim 11, wherein the metal oxide film comprises HfO2, ZrO2, or Al2O3.

17. The substrate manufacturing method of claim 11, wherein the step of exposing the substrate to the process gas containing the silanol gas is performed at a substrate temperature of about 150 °C or lower in the absence of any oxidizing agent and hydrolyzing agent.

18. The substrate manufacturing method of claim 11, wherein the silanol gas is selected from the group consisting of triterpenoid silanol, triterpenoid butyrosilanol, and bis(terpenoid butyrosilanol)isopropoxysilanol.

19. The substrate manufacturing method of claim 11 further comprises: repeatedly exposing the substrate to hydrogen (H2) excited by the plasma source, selectively depositing the metal oxide film, and exposing the substrate to the process gas containing the silanol gas at least once, to increase the thickness of the metal oxide film and the SiO2 thin film on the dielectric material.

20. The substrate manufacturing method of claim 11, wherein the dielectric material surrounds the metal layer.

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