Selective deposition using hydrolysis

Abstract

Methods and apparatus are provided for selectively depositing a metal oxide on a metal surface relative to a dielectric surface. The selective deposition is achieved by exposing the metal and dielectric surfaces to a blocking agent capable of forming a hydrolyzable bond with the metal while forming a non-hydrolyzable bond with the dielectric, then immersing the surface in water to cleave the hydrolyzable bonds and leave a blocking surface on the dielectric surface, followed by selectively depositing the metal oxide on the metal surface relative to the dielectric surface. The blocking agent is deposited by wet or dry techniques and may include, for example, an alkylaminosilane or an alkylchlorosilane.

Description

[0001] Incorporated by Reference

[0002] The application form is filed concurrently with this specification as a part of this application. Each application to which this application claims the benefit of or priority is incorporated herein by reference in its entirety and for all purposes as identified in the concurrently filed application form. Background Art

[0003] The manufacture of semiconductor devices includes the manufacture of microprocessors, logic and memory devices. Such devices can be manufactured using a variety of techniques, including self-aligned patterns, such as double or quad patterns, gap fill processes and other techniques. Some processes involve forming structures comprising silicon oxide and metals (e.g., copper). Conventional techniques for forming such structures may be limited. Summary of the invention

[0004] Methods for processing substrates are provided. One aspect relates to a method for selectively depositing a metal oxide on an exposed metal surface relative to a dielectric material on a substrate, the method comprising: (a) providing the substrate including the dielectric material and the exposed metal surface; (b) exposing the substrate to a blocking agent before depositing the metal oxide to non-selectively adsorb the blocking agent on both the dielectric material and the exposed metal surface; (c) after exposing the substrate to the blocking agent and before depositing the metal oxide, selectively removing the blocking agent from the exposed metal surface; and (d) selectively depositing the metal oxide on the exposed metal surface relative to the dielectric material on the substrate.

[0005] In various embodiments, selectively removing the blocking agent is performed by contacting the substrate with water. In some embodiments, selectively removing the blocking agent is performed by immersing the substrate in water.

[0006] In various embodiments, the blocking agent is a silicamide.

[0007] In various embodiments, the blocking agent is an alkylchlorosilane. Exemplary alkylchlorosilanes have the chemical structure Cl x Si([CH3(CH2) y ]) (4-x) , where x is an integer between 1 and 3, inclusive, and y is an integer greater than or equal to 1.

[0008] In various embodiments, the blocking agent is an alkylaminosilane. Exemplary alkylaminosilanes have the chemical structure [(CH3)2N] x Si([CH3(CH2) y ]) (4-x), where x is an integer between 1 and 3, inclusive, and y is an integer greater than or equal to 1.

[0009] In various embodiments, the blocking agent is provided in an aprotic polar solvent.

[0010] The blocking agent may form a hydrolyzable bond with the exposed metal surface but not with the dielectric material.

[0011] The substrate may be exposed to the blocking agent by immersing the substrate in a wet solution of the blocking agent. In some embodiments, the substrate is exposed to the blocking agent at a temperature between about 25°C and about 100°C.

[0012] In some embodiments, the substrate is exposed to the blocking agent at a temperature between about 60°C and about 100°C.

[0013] In various embodiments, the substrate is exposed to the blocking agent by introducing the blocking agent in a vapor phase. In some embodiments, the substrate is exposed to the blocking agent at a temperature between about 100°C and about 300°C.

[0014] In some embodiments, the substrate is exposed to the blocking agent at a temperature between about 200°C and about 250°C.

[0015] In various embodiments, the substrate is exposed to the blocking agent for a duration of between about 10 seconds to about 60 seconds.

[0016] In various embodiments, selectively removing the blocking agent from the substrate is performed at room temperature.

[0017] Selectively removing the blocker from the substrate may selectively hydrolyze bonds between the blocker and the exposed metal surface.

[0018] In various embodiments, the metal oxide deposited is aluminum oxide.

[0019] In various embodiments, the metal oxide is selectively deposited on the exposed metal surface relative to the dielectric material using atomic layer deposition.

[0020] In various embodiments, the exposed metal surface comprises a metal selected from the group consisting of tungsten, titanium, and aluminum.

[0021] In various embodiments, the dielectric material comprises silicon. In some embodiments, the dielectric material is selected from the group consisting of silicon oxide, silicon nitride, and carbon-doped silicon oxide.

[0022] In various embodiments, the substrate is patterned.

[0023] In various embodiments, the hydrolysis results in the exposed metal surface having a hydrogen-terminated and / or hydroxyl-terminated surface.

[0024] Another aspect relates to a method for selectively depositing a metal oxide on an exposed metal surface relative to a dielectric material on a substrate, the method comprising: (a) providing the substrate comprising the dielectric material and the exposed metal surface; (b) exposing the substrate to a blocking agent before depositing the metal oxide to non-selectively adsorb the blocking agent on both the dielectric material and the exposed metal surface; (c) after exposing the substrate to the blocking agent and before depositing the metal oxide, contacting the substrate with water to selectively remove the blocking agent from the exposed metal surface; and (d) selectively depositing the metal oxide on the exposed metal surface relative to the dielectric material on the substrate.

[0025] These and other aspects will be described below with reference to the associated drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a process flow diagram depicting operational steps for performing a method.

[0027] Figure 2A-2E is a schematic diagram of one example of a mechanism for selectively depositing material on an exposed metal surface relative to a dielectric surface, according to certain disclosed embodiments.

[0028] Figure 3 is a timing diagram showing an example of a cycle in a method according to certain disclosed embodiments.

[0029] Figure 4 is a schematic diagram of an example processing chamber for performing the disclosed embodiments.

[0030] Figure 5 is a schematic diagram of an exemplary processing tool for performing the disclosed embodiments.

[0031] Fig. 6A is a graph depicting the thickness of films deposited using a specific number of ALD cycles for deposition processes on tungsten surfaces and silicon oxide surfaces.

[0032] Figure 6B is a graph depicting the thickness of films deposited using a specific number of ALD cycles for deposition processes on tungsten surfaces and silicon oxide surfaces that have been exposed to dimethyldichlorosilane.

[0033] Figure 7is a graph depicting the thickness of films deposited using a specific number of ALD cycles for deposition processes according to certain disclosed embodiments on tungsten surfaces and silicon oxide surfaces that had been exposed to dimethyldichlorosilane and washed with water. DETAILED DESCRIPTION

[0034] In the following description, many specific details are set forth to provide a thorough understanding of the embodiments presented. The disclosed embodiments may be implemented without some or all of these specific details. In other cases, well-known processing operations are not described in detail to avoid unnecessarily obscuring the disclosed embodiments. Although the disclosed embodiments will be described in conjunction with specific embodiments, it should be understood that they are not intended to limit the disclosed embodiments.

[0035] Semiconductor manufacturing processes often involve depositing and etching various materials in a patterned scheme to form a specific type of semiconductor device. Selective deposition of metal oxide films on dielectric surfaces in the presence of metal surfaces can be achieved, for example, by depositing aluminum oxide on silicon oxide by atomic layer deposition (ALD) in the presence of a copper surface. However, the reverse process of selectively depositing dielectrics on metal surfaces by ALD in the presence of silicon oxide surfaces faces challenges - in particular, the lack of selective inhibitor molecules that would allow the process to be converted to other masking techniques rather than using selective deposition techniques. For example, selective deposition of aluminum oxide on copper surfaces by ALD in the presence of exposed silicon oxide surfaces can be challenging.

[0036] Provided herein are methods for selectively depositing materials on metal surfaces relative to dielectric surfaces. Certain disclosed embodiments involve exploiting the reactivity of metal-oxygen-silicon (MO-Si) bonds relative to silicon-oxygen-silicon (Si-O-Si) bonds in water to achieve selective removal of blocking agents from metal surfaces, while the blocking agents on dielectric surfaces remain. Certain disclosed embodiments may be particularly suitable for selectively depositing dielectrics on metals relative to dielectric surfaces.

[0037] For example, the disclosed embodiments may involve depositing silicon oxide (e.g., SiO2), silicon nitride (SiN), carbon-doped silicon nitride, aluminum oxide (Al2O3), silicon oxycarbide, silicon carbide nitride, and silicon oxycarbide nitride on a metal-containing surface such as a metal surface or a metal alloy surface. Examples of metals include: tungsten, titanium, aluminum, and copper. A non-limiting example of silicon oxycarbide is a silicon nitride having the chemical formula SiO x C y A non-limiting example of silicon carbide nitride is a silicon oxycarbide having the chemical formula SiC a N bA non-limiting example of silicon oxycarbon nitride is a silicon oxycarbon nitride having the chemical formula SiO i C j N k Silicon nitride and carbon oxide, where 2i+4j+3k=4.

[0038] The techniques described herein may involve thermal atomic layer deposition (ALD) and / or plasma enhanced atomic layer deposition (PEALD).That is, in various embodiments, a reaction between a silicon-containing precursor and an oxidant is performed to form silicon oxide.

[0039] ALD is a technique for depositing thin layers of material using sequential self-limiting reactions. Typically, an ALD cycle includes the following operations: delivering and adsorbing at least one reactant onto a substrate surface, and then reacting the adsorbed reactant with one or more reactants to form a portion of a film layer. For example, a silicon oxide deposition cycle may include the following operations: (i) delivering / adsorbing a silicon-containing precursor, (ii) purging a silicon-containing precursor in a chamber, (iii) delivering an oxygen-containing reactant or an oxygen-containing gas, and (iv) purging the oxygen-containing reactant from the chamber. In a PEALD process, the delivery of the oxygen-containing reactant may be accompanied by the generation of a plasma in an oxygen-containing reactant environment.

[0040] Unlike chemical vapor deposition (CVD) techniques, the ALD process uses a surface-mediated deposition reaction to deposit films layer by layer. In one embodiment of the ALD process, a substrate surface containing a group of surface active sites is exposed to a first precursor, such as a silicon-containing precursor, which is provided in a dosed gas phase distribution to a chamber containing the substrate. The molecules of the first precursor are adsorbed on the substrate surface, including chemically adsorbed substances and / or physically adsorbed molecules of the first precursor. It should be understood that when a compound is adsorbed to the substrate surface as described herein, the adsorption layer may include the compound and derivatives of the compound. For example, the adsorption layer of a silicon-containing precursor may include a silicon-containing precursor and a derivative of the silicon-containing precursor. After the first precursor is dosed, the chamber is then evacuated to remove most or all of the remaining first precursor in the gas phase, so that mainly or only the adsorbed substance remains. In some implementations, the chamber may not be completely evacuated. For example, the chamber may be evacuated to a level that makes the local pressure of the first precursor in the gas phase low enough to slow down the reaction. A second reactant (e.g., an oxygen-containing reactant) is introduced into the chamber so that some of these molecules react with the first precursor adsorbed on the surface. In some processes, the second reactant reacts immediately with the adsorbed first precursor. The chamber can then be evacuated again to remove unbound second reactant molecules. As described above, in some embodiments, the chamber may not be completely evacuated. Additional ALD cycles may be used to build up film thickness.

[0041] In certain embodiments, the dose of the ALD first precursor partially saturates the surface of the substrate. In some embodiments, the dosing phase of the ALD cycle is terminated before the precursor is contacted with the substrate to uniformly saturate the surface. Typically, the precursor flow is shut off or diverted at this time, and only the gas flow is purged. By operating in this subsaturated state, the ALD process reduces cycle time and improves throughput. However, since the precursor adsorption is not saturation-limited, the adsorbed precursor concentration may vary slightly across the substrate surface. An embodiment of operating the ALD process in a subsaturated state is provided in U.S. Patent Application No. 14 / 061,587 (now U.S. Patent No. 9,355,839), filed on October 23, 2013, entitled "SUB-SATURATED ATOMIC LAYER DEPOSITION AND CONFORMAL FILM DEPOSITION," which is incorporated herein by reference in its entirety.

[0042] As described, in some implementations, the ALD method includes plasma activation. As described herein, the ALD method and apparatus described herein can be a conformal film deposition (CFD) method, which is generally described in U.S. Patent Application No. 13 / 084,399, filed on April 11, 2011, entitled "PLASMA ACTIVATED CONFORMAL FILM DEPOSITION" (now U.S. Patent No. 8,728,956) and U.S. Patent Application No. 13 / 084,305, filed on April 11, 2011, entitled "SILICON NITRIDE FILMS AND METHODS", which are incorporated herein by reference in their entirety.

[0043] Selective masking of one surface relative to another can be accomplished using a two-step process. The first operation is non-selective adsorption of inhibitor molecules. The second operation is selective removal of the inhibitor molecules from one surface by wet etching using pure water or another hydrolyzing agent that hydrolyzes the chemical bonds that attach the inhibitor molecules to one surface and not the other. This method can be performed so that one surface is silicon-based and the other is metal-based. The deposition method used after net inhibition can be atomic layer deposition of metal oxide films.

[0044] Selective deposition of metal oxide films onto dielectric surfaces in the presence of metal surfaces can be performed using ALD aluminum oxide deposition on dielectrics such as silicon oxide in the presence of tungsten or copper or other metal surfaces. However, inhibitors used for selective deposition to deposit on dielectrics may not be selective for metal surfaces due to the hydroxyl termination found on typical dielectric surfaces.

[0045] Certain disclosed embodiments involve the reverse situation: selective deposition of ALD aluminum oxide on tungsten or copper or other metal surfaces in the presence of a dielectric surface.

[0046] Some ALD dielectric depositions involve metal organic precursors (e.g., trimethylaluminum, or tetrakis(dimethylamino)zirconium) and water to deposit the film. An ALD cycle may involve exposing the metal organic precursor to a surface where the natural hydroxyl or oxide species react with the precursor to form a surface-oxygen-metal bond, thereby replacing one of the metal organic ligands with an amine (e.g., HN(CH3)2) or a hydrocarbon (e.g., CH4). One method to block deposition on a surface is to eliminate these reactive hydroxyl / oxide species (surface -OH or surface =O) and terminate with a hydrocarbon group (surface -C x H y ) to replace them. Reagents such as silicamides (e.g. Si(CH3)3(NMe2)) readily carry out this reaction but are not selective.

[0047] One solution to this problem of non-selectivity is to eliminate the oxide on the metal surface by a reduction reaction such as described elsewhere herein. This method involves selective deposition on dielectrics and not on metals.

[0048] To achieve selective deposition on metals and not on dielectrics, one embodiment involves non-selectively reacting both dielectric and metal surfaces with an alkylating agent such as silicamide, followed by selective removal of the agent using water to form the metal surface. Water readily hydrolyzes the bond between the inhibitor and the metal surface (e.g., MO-Si(CH3)3+H2O->M-OH+HO-Si(CH3)3) but does not readily react on dielectric surfaces.

[0049] Selective growth of metal oxides on metal surfaces and not on dielectric surfaces can be performed by selectively blocking the dielectric surface using certain disclosed embodiments.

[0050] Figure 1 Process flow diagrams are provided that depict operations in methods performed according to certain disclosed embodiments. Process temperatures that may be suitable for certain disclosed embodiments depend on the technology used for each operation. Certain embodiments of certain operations described herein may be performed at a temperature between about 70° C. and about 200° C., or at a temperature between about 100° C. and about 150° C.

[0051] In operation 101, a substrate having an exposed metal surface and an exposed dielectric surface is provided. The substrate can be a silicon wafer, for example, a 200-mm wafer, a 300-mm wafer, or a 450-mm wafer, comprising a wafer having one or more layers of materials such as dielectrics, conductive layers, or semiconductor materials deposited thereon. Non-limiting examples of lower layers include dielectric layers and conductive layers, and materials include but are not limited to silicon oxide, silicon nitride, silicon carbide, metal oxides, metal nitrides, metal carbides, and metals. In some embodiments, the substrate may have been patterned. In some embodiments, the substrate may not be patterned. In some embodiments, the substrate comprises a dielectric material and a through hole filled with a metal (such as an interconnect).

[0052] In various embodiments, the dielectric material can be a silicon-containing material such as silicon oxide, silicon nitride, carbon-doped silicon oxide, or a combination thereof. In various embodiments, the dielectric material can be an ultra-low-k (ULK) dielectric. In certain embodiments, the dielectric material can be a semiconductor material rather than a dielectric material. In various embodiments, the dielectric layer comprises hydroxyl-terminated silicon oxide.

[0053] In various embodiments, the exposed metal surface comprises one or more of the following metals or alloys thereof: tungsten, aluminum, titanium, titanium aluminum, and combinations thereof.

[0054] In some embodiments, the substrate is patterned with vias that are filled with a metal such as copper. In some embodiments, the vias are filled with copper oxide, ruthenium, and / or ruthenium oxide. In some embodiments, copper is reduced by exposure to a reducing agent such as hydrogen or hydrazine in preparation for subsequent operations.

[0055] Figure 2A is a schematic diagram of an exemplary substrate having an exposed silicon oxide surface 201 and an exposed metal surface 203 .

[0056] Back to Figure 1 In operation 103, the substrate is exposed to a blocking agent that adsorbs or deposits on both metal and dielectric surfaces regardless of their surface chemistry or morphology. In certain embodiments, the blocking agent adsorbs and deposits on both metal and dielectric surfaces.

[0057] Figure 2B is a schematic diagram of an exemplary substrate having an exposed silicon oxide surface 201 and an exposed metal surface 203, on which blocking agents are adsorbed to form a blocking surface 205 having adsorbed blocking agents 207 having Si-O-Si bonds on the dielectric and adsorbed blocking agents 209 having MO-Si bonds on the metal.

[0058] It should be understood that although a flat surface is depicted in this figure, certain disclosed embodiments are applicable to surfaces having topography including features of various sizes and heights. Exemplary features include: holes, trenches, vias, and other features. The substrate is exposed to a blocking agent that reacts with the exposed metal surface and the dielectric material. The blocking agent may be one or more alkylating agents such as silicamide. The blocking agent is reactive to both dielectric and metal surfaces alike, but can be removed from metal surfaces by hydrolysis, but not from dielectric surfaces by hydrolysis.

[0059] The blocking agent can be any chemical compound capable of forming a hydrolyzable bond with a metal surface and a non-hydrolyzable bond with a dielectric surface. In various embodiments, the blocking agent forms a hydrolyzable bond with the metal. In various embodiments, the blocking agent is capable of forming a metal-oxygen-silicon bond with the metal and is capable of forming a silicon-oxygen-silicon bond with a silicon-containing dielectric material.

[0060] Examples of blocking agents include alkylaminosilanes and alkylchlorosilanes. Alkylaminosilanes may be used in certain embodiments because byproducts resulting from subsequent hydrolysis and selective deposition on metals may be less harmful to the surface of the semiconductor substrate than byproducts of hydrolysis involving alkylchlorosilanes which may form hydrogen chloride (HCl) that may damage the substrate surface.

[0061] Suitable alkylaminosilanes may have the general chemical formula [(CH3)2N] x Si([CH3(CH2) y ]) (4-x) , where x is an integer between 1 and 3, inclusive, and y is any integer greater than or equal to 1.

[0062] Suitable alkylchlorosilanes may have the general chemical formula Cl x Si([CH3(CH2) y ]) (4-x) , where x is an integer between 1 and 3, inclusive, and y is any integer greater than or equal to 1.

[0063] An exemplary alkylchlorosilane that can be used is dimethyldichlorosilane.

[0064]

[0065] The exposure to the blocking agent may be performed using one of the following techniques: a wet technique and a dry technique. The wet technique may include immersing the substrate in a solution having the blocking agent therein to expose the surface of the substrate to the blocking agent, or using a spin coater to deliver a solution having the blocking agent to the surface of the substrate.

[0066] When alkylaminosilane or alkylchlorosilane is used as the blocking agent, the solution with the blocking agent is a non-aqueous polar solvent. In various embodiments, the solvent can be an aprotic polar solvent. Possibly suitable examples of solvents for alkylaminosilane include dimethylformamide (DMF), diethyl ether and acetonitrile:

[0067]

[0068] Examples of solvents for alkylchlorosilanes include propylene glycol methyl ether (PGME):

[0069]

[0070] Other potential solvents include alcohols.

[0071] The dry technique may include preparing a blocking agent in a vapor or gas phase and delivering the blocking agent in a vapor or gas phase to a chamber housing a substrate so that the substrate surface is exposed to the blocking agent.

[0072] Suitable temperatures for this operation depend on the selected technique and are limited by the thermal decomposition of the blocking agent. For wet techniques, the solution can be heated or cooled to about room temperature, or about 25°C, or at least about room temperature, or at least about 60°C, or a temperature between about 25°C and about 100°C, or a temperature between about 60°C and about 100°C. For dry techniques, the substrate can be maintained on a susceptor, the temperature of which is set higher than the temperature at which thermal decomposition of the blocking agent occurs. In various embodiments, the temperature can be between about 100°C and about 300°C, or between about 200°C and about 250°C.

[0073] Operation 103 may be performed for a duration between about 10 seconds and about 60 seconds.

[0074] Back to Figure 1In operation step 105, the chamber containing the substrate may be optionally purged to remove excess blocking agent. The step of purging the chamber may involve flowing a purge gas or sweep gas, which may be a carrier gas or a different gas used in other operation steps. In some embodiments, the purge step may involve evacuating the chamber. However, in some embodiments, the chamber is not evacuated. Examples of sweep gases include, but are not limited to, argon, nitrogen, hydrogen, and helium. In some embodiments, operation 105 may include one or more evacuation sub-stages for evacuating the processing chamber. Alternatively, it should be understood that operation 105 may be omitted in some embodiments. Operation 105 may have any suitable duration, such as between about 0 seconds and about 60 seconds, for example, about 0.01 seconds. In some embodiments, increasing the flow rate of one or more sweep gases may reduce the duration of operation 105. For example, the sweep gas flow rate can be adjusted based on the thermodynamic properties of the various reactants, and / or the geometric features of the processing chamber, and / or the plumbing of the processing chamber to adjust the duration of operation 105. In a non-limiting example, the duration of the sweep phase can be adjusted by adjusting the sweep gas flow rate. This can reduce the deposition cycle time, which can increase substrate throughput. After sweeping, the blocking agent remains adsorbed on the metal and dielectric surfaces.

[0075] In operation 107, the blocking agent is selectively removed from the metal surface. In certain embodiments, this operation involves contacting the substrate with water. In various embodiments, contacting the substrate with water can be performed by immersing the substrate in water or delivering water to the substrate surface. In various embodiments, the substrate surface is hydrolyzed to selectively remove the blocking agent from the metal surface relative to the dielectric material, so that the blocking agent remains on the dielectric material and the metal surface is exposed. The hydrolysis can be performed by immersing the substrate in a container of water. Operation 107 can be performed at room temperature. The hydrolysis is not performed using water vapor or gas phase techniques. In certain embodiments, an aqueous hydrolysis technique is used.

[0076] The hydrolysis can be carried out at room temperature or any temperature above room temperature. The substrate is immersed at room temperature to hydrolyze the blocking agent, thereby breaking the metal-oxygen-silicon bonds on the metal surface within a few seconds. Since the silicon-oxygen-silicon bonds are not hydrolyzable and do not react with water, the blocking agent remains on the dielectric surface, thereby producing a substrate with blocking agent selectively on the dielectric material relative to the exposed metal surface.

[0077] Without being limited to a particular theory, it is believed that immersion in water results in a hydrogen-terminated or hydroxyl-terminated metal surface that is susceptible to subsequent deposition, thereby leaving the blocking agent on the dielectric surface that is less susceptible to subsequent deposition.

[0078] In operations 807-818, a metal oxide, such as aluminum oxide, may be selectively deposited on the exposed metal surface relative to the dielectric surface. For example, ALD may be performed whereby a deposition precursor is selectively adsorbed on the exposed metal surface and an oxidant is used to selectively form the metal oxide on the exposed metal surface. For example, aluminum oxide deposited with ALD may involve the use of a deposition precursor such as trimethylaluminum.

[0079] Figure 2C is a schematic diagram of an exemplary substrate in which water is directed onto a substrate having an adsorbed blocking surface 205 having an adsorbed blocking agent 207 having Si-O-Si bonds on a dielectric and an adsorbed blocking agent 209 having MO-Si bonds on a metal.

[0080] Figure 2D is a schematic diagram of an exemplary substrate in which hydrogen breaks the hydrolyzable bonds between the blocker 209 on the metal and the metal surface, thereby producing a hydroxyl terminated metal surface 211.

[0081] Figure 2E is a schematic diagram of an exemplary substrate in which adsorbed blocking agents are removed from a metal surface by hydrolysis while adsorbed blocking agents 207 remain on a dielectric surface, thereby producing a hydroxyl-terminated metal surface 213 that is ready for deposition of, for example, a metal oxide material.

[0082] Figure 3 Provides a timing diagram of various operations performed according to certain disclosed embodiments. Figure 3 The process 300 in FIG. 3 includes only two deposition cycles 399A and 399B, it being understood that more than two deposition cycles (and in some cases, only one deposition cycle) may be performed in certain embodiments.

[0083] Figure 3 The various stages in an example deposition process 300 are shown for various process parameters such as: argon flow as a carrier gas and / or purge gas, barrier gas flow, water flow (here for immersion processing rather than gas processing), metal precursor flow, exposure of oxygen-containing reactants, and reducing agent flow. Although this example describes ALD using oxygen-containing reactants as a deposition technique, and the plasma is not Figure 3 However, in certain embodiments, an oxygen-containing plasma may be used to deposit the metal oxide such that the plasma is generated when an oxygen-containing reactant flows. Figure 3The lines in represent when the flow is turned on or off, and when water immersion is performed. Various disclosed embodiments depend on process parameters, which include but are not limited to: the flow rates of inert gas, blocking agent, and reactant; the flow rates of argon as carrier gas, metal precursor, and oxygen-containing gas; substrate temperature; and process chamber pressure.

[0084] like Figure 3 As depicted in FIG. 3 , prior to selective deposition, a blocking agent exposure phase 303 is performed whereby a blocking agent is delivered while the metal precursor and oxygen-containing reactant flows are shut off. In this example, argon gas may be used to deliver the blocking agent. No water is used; it should be understood that, as Figure 3 The water mentioned in the above description refers to immersing the substrate in water, rather than introducing water in a gas phase or vapor phase. This may correspond to Figure 1 Operation 103.

[0085] A water dip 307 is performed, whereby the substrate is immersed in a bath of water. It will be appreciated that this step can be performed in a few seconds and can be performed at room temperature. In some cases, this can be performed at a higher temperature, but immersing the wafer in water at room temperature can achieve a rapid hydrolysis reaction in a few seconds without substantially extending the overall processing time. Although the argon is depicted as being in the "on" stage, the substrate can be taken out of the chamber for the dip and then subsequently placed back into the chamber. This can correspond to Figure 1 Operation 107.

[0086] Deposition cycle 399A may correspond to Figure 1 In some embodiments, the deposition cycle 399 comprises: Figure 3. The deposition cycle 399A includes: a metal precursor exposure phase 311-1A, a sweep phase 311-2A, an oxygen-containing reactant exposure phase 311-3A, and a sweep phase 311-4A. During the silicon-containing precursor exposure phase 311-1A, an argon gas flow may be turned on to assist in the delivery of the metal precursor, while the blocking agent flow is turned off, the metal precursor flow is turned on, and the oxygen-containing reactant flow is turned off. In the sweep phase 311-2A, all gas flows and plasma are turned off except for the argon flow used as a sweep gas. In the oxygen-containing reactant exposure phase 311-3A, the argon gas flow may continue to be turned on, while the blocking agent flow is turned off, the metal precursor gas flow is turned off, and the oxygen-containing reactant flow is turned on. In the sweep phase 311-4A, the argon gas flow is turned on to serve as a sweep gas, while the blocking agent flow is turned off, the metal precursor gas flow is turned off, and the oxygen-containing reactant flow is turned off. In this example, it is determined that the metal oxide is not deposited to the desired thickness, so these operations are repeated in deposition cycle 399B. Deposition cycle 399B includes: a metal precursor exposure phase 311-1B, in which only argon gas flow and metal precursor gas flow are turned on, and the blocking agent gas flow and oxygen-containing reactant gas flow are turned off; a sweep phase 311-2B, in which only argon is flowed as a sweep gas; an oxygen-containing reactant exposure phase 311-3B, in which only argon and oxygen-containing reactant are turned on, and the blocking agent and metal precursor gas flows are turned off; and a sweep phase 311-4B, in which argon is flowed as a sweep gas.

[0087] Device

[0088] Figure 4 A schematic diagram of one embodiment of an atomic layer deposition (ALD) processing station 400 having a processing chamber body 402 for maintaining a low pressure environment is depicted. This tool can be used to deliver a blocking agent and deposit a metal oxide film after immersing the substrate with the blocking agent in water.

[0089] Multiple ALD processing stations 400 may be included in a generally low pressure processing tool environment. For example, Figure 5 One embodiment of a multi-station processing tool 500 is depicted. In some embodiments, one or more hardware parameters of the ALD processing station 400 (including those discussed in detail below) can be programmatically adjusted by one or more computer controllers 450.

[0090] The ALD processing station 400 is in fluid communication with a reactant delivery system 401a to deliver process gases to a distribution showerhead 406. The reactant delivery system 401a includes a mixing vessel 404 for mixing and / or regulating process gases, such as a blocking agent gas, a metal precursor gas, or an oxygen-containing gas, delivered to the showerhead 406. One or more mixing vessel inlet valves 420 can control the introduction of process gases into the mixing vessel 404.

[0091] For example, Figure 4 Embodiments include vaporization point 403 for vaporizing liquid reactants to be supplied to mixing container 404. In some embodiments, vaporization point 403 can be a heated evaporator. Saturated reactant vapors produced from such an evaporator will condense in the downstream delivery pipeline. Incompatible gases exposed to condensed reactants will produce small particles. These small particles may block pipelines, hinder valve operation, contaminate substrates, etc. Some methods for dealing with these problems involve cleaning and / or emptying the delivery pipeline to remove residual reactants. However, cleaning the delivery pipeline will increase the processing station cycle time and reduce the processing station throughput. Therefore, in some embodiments, the delivery pipeline downstream of vaporization point 403 can be heat traced. In some examples, mixing container 404 can also be heat traced. In a non-limiting example, the pipeline downstream of vaporization point 403 has an increased temperature distribution, extending from about 100°C to about 150°C at mixing container 404.

[0092] In some embodiments, the liquid precursor or liquid reactant can be vaporized at the liquid injector. For example, the liquid injector can inject a pulse of the liquid reactant into the carrier gas flow upstream of the mixing container. In one embodiment, the liquid injector can vaporize the reactant by flashing the liquid from a higher pressure to a lower pressure. In another example, the liquid injector can atomize the liquid into dispersed droplets that are then vaporized in a heated delivery pipe. Smaller droplets can vaporize faster than larger droplets, thereby reducing the delay between liquid injection and completion of vaporization. Faster vaporization can reduce the length of the pipeline downstream of the vaporization point 403. In one embodiment, the liquid injector can be loaded directly into the mixing container 404. In another embodiment, the liquid injector can be loaded directly into the spray head 406.

[0093] In some embodiments, a liquid flow controller (LFC) can be set upstream of the vaporization point 403 to control the mass flow of the liquid for vaporization and delivery to the processing station 400. For example, the LFC can include a thermal mass flow meter (MFM) located downstream of the LFC. Then the plunger valve of the LFC can be adjusted in response to a feedback control signal provided by a proportional integral differential (PID) controller that is electrically communicated with the MFM. However, it can take one second or more to use feedback control to stabilize the liquid flow. This can extend the time of dosing liquid reactants. Therefore, in some embodiments, the LFC can be dynamically switched between a feedback control mode and a direct control mode. In some embodiments, this can be performed by disabling the sensing pipeline of the PID controller and the LFC.

[0094] Showerhead 406 distributes processing gas toward substrate 412. Figure 4 In the illustrated embodiment, substrate 412 is positioned below showerhead 406 and is shown resting on pedestal 408. Showerhead 406 may have any suitable shape and may have any suitable number and arrangement of ports to distribute process gases to substrate 412.

[0095] In some embodiments, the pedestal 408 may be raised or lowered to expose the substrate 412 to the volume between the substrate 412 and the showerhead 406. It should be appreciated that in some embodiments, the pedestal height may be programmatically adjusted via a suitable computer controller 450.

[0096] In another case, in an embodiment where the plasma is ignited, adjusting the height of the pedestal 408 can allow the plasma density to be varied during a plasma activation cycle in the process. At the end of the processing phase, the pedestal 408 can be lowered to allow the substrate 412 to be removed from the pedestal 408 in another substrate transfer phase.

[0097] In some embodiments, the susceptor 408 may be temperature controlled by a heater 410. In some embodiments, the susceptor 408 may be heated to a temperature between about 70°C and about 200°C, or between about 100°C and about 120°C.

[0098] Additionally, in some embodiments, pressure control for the processing station 400 may be provided by a butterfly valve 418. Figure 4 In the embodiment shown in FIG. 4 , butterfly valve 418 throttles the vacuum provided by a downstream vacuum pump (not shown). However, in some embodiments, pressure control of process station 400 can also be adjusted by changing the flow rate of one or more gases introduced into process station 400.

[0099] In some embodiments, the position of the showerhead 406 can be adjusted relative to the pedestal 408 to change the volume between the substrate 412 and the showerhead 406. In addition, it should be understood that the vertical position of the pedestal 408 and / or the showerhead 406 can be changed by any suitable mechanism within the scope of the present disclosure. In some embodiments, the pedestal 408 can include a rotation axis for rotating the orientation of the substrate 412. It should be understood that in some embodiments, one or more of these exemplary adjustments can be performed programmatically by one or more appropriate computer controllers 450.

[0100] In some embodiments where plasma can be used as described above, the showerhead 406 and the base 408 are electrically connected to a radio frequency (RF) power source 414 and a matching network 416 to provide power to the plasma. In some embodiments, the energy of the plasma can be controlled by controlling one or more of the pressure of the processing station, the concentration of the gas, the RF source power, the RF source frequency, and the timing of the plasma power pulse. For example, the RF power source 414 and the matching network 416 can be operated at any suitable power to form a plasma having a component of a desired free radical species. An example of a suitable power is about 150W to about 6000W. Before selectively depositing silicon oxide on silicon oxide relative to silicon nitride, plasma can be used during the treatment of the silicon nitride surface. The RF power source 414 can provide RF power of any appropriate frequency. In some embodiments, the RF power source 414 can be configured to control a high frequency RF power source and a low frequency RF power source that are independent of each other. Exemplary low frequency RF frequencies can include, but are not limited to, frequencies between 0kHz and 500kHz. Exemplary high frequency RF frequencies may include, but are not limited to, frequencies between 1.8 MHz and 2.45 GHz, or frequencies greater than about 13.56 MHz, or greater than 27 MHz, or greater than 40 MHz, or greater than 60 MHz. It should be understood that any suitable parameter may be discretely or continuously adjusted to provide plasma energy for surface reactions.

[0101] In some embodiments, the plasma can be monitored in situ by one or more plasma monitors. In one case, the plasma power can be monitored by one or more voltage and current sensors (e.g., VI probes). In another case, the plasma density and / or the concentration of the process gas can be measured by one or more optical emission spectroscopy sensors (OES). In some embodiments, one or more plasma parameters can be adjusted programmatically based on the measurement results from such an in-situ plasma monitor. For example, an OES sensor can be used in a feedback loop to provide programmatic control of the plasma power. It should be understood that in some embodiments, other monitors can be used to monitor plasma and other process characteristics. Such monitors may include, but are not limited to, infrared (IR) monitors, acoustic monitors, and pressure sensors.

[0102] In some embodiments, instructions for the controller 450 may be provided via input / output control (IOC) sequencing instructions. In one example, instructions for setting the conditions of a process stage may be included in a corresponding recipe stage of a process recipe. In some cases, the process recipe stages may be arranged in sequence so that all instructions for a process stage are performed simultaneously with the process stage. In some embodiments, instructions for setting one or more reactor parameters may be included in a recipe stage. For example, a first recipe stage may include instructions for setting the flow rate of a blocking agent gas such as an alkylaminosilane or an alkylchlorosilane, instructions for setting the flow rate of a carrier gas (e.g., argon), and time delay instructions for the first recipe stage. In some embodiments, after the first recipe stage, the substrate is removed from the chamber to immerse it in a water bath and selectively remove the blocking agent from the metal surface, and then the substrate in the replacement chamber is replaced to perform a second recipe stage. The second recipe stage may include instructions for setting the flow rate of an inert gas and / or a metal precursor gas, instructions for setting the flow rate of a carrier gas (such as argon); and time delay instructions for the second recipe stage. The following third formulation stage may include instructions for adjusting or stopping the flow rate of the inert gas and / or the reactant gas, instructions for adjusting the flow rate of the carrier gas or the purge gas, and time delay instructions for the third formulation stage. The fourth formulation stage may include instructions for adjusting the flow rate of the oxygen-containing gas, instructions for adjusting the flow rate of the carrier gas or the purge gas, and time delay instructions for the fourth formulation stage. The following fifth formulation stage may include instructions for adjusting or stopping the flow rate of the inert gas and / or the reactant gas, instructions for adjusting the flow rate of the carrier gas or the purge gas, and time delay instructions for the fifth formulation stage. It should be understood that within the scope of the present disclosure, these formulation stages may be further subdivided and / or repeated in any appropriate manner. In some embodiments, the controller 450 may include the following regarding Figure 5Any features described for the system controller 550.

[0103] As described above, one or more processing stations may be included in a multi-station processing tool. Figure 5 A schematic view of one embodiment of a multi-station processing tool 500 is shown having an inbound load lock 502 and an outbound load lock 504, either or both of which may include a remote plasma source. A robot 506 at atmospheric pressure is configured to move wafers from a box loaded by a wafer boat 508 into the inbound load lock 502 via an atmospheric port 510. The wafer is placed on a pedestal 512 in the inbound load lock 502 by the robot 506, the atmospheric port 510 is closed, and the load lock is evacuated. In addition, the wafer may also be heated in the inbound load lock 502, for example to remove moisture and adsorbed gases. Next, a chamber transfer port 516 leading to a processing chamber 514 is opened, and another robot (not shown) places the wafer into the reactor on a pedestal at the first station shown in the reactor for processing. Although in Figure 5 The embodiment depicted in FIG. 1 includes a load lock, but it should be understood that in some embodiments, substrates may be allowed to enter the processing station directly.

[0104] The depicted processing chamber 514 includes four processing stations, Figure 5 The stations are numbered 1 to 4 in the illustrated embodiment. Each station has a heated susceptor (shown as 518 for station 1) and a gas line inlet. It should be understood that in some embodiments, each processing station may have different or multiple uses. For example, in some embodiments, the processing station may be switchable between ALD and plasma-enhanced ALD processing modes. Additionally or alternatively, in some embodiments, the processing chamber 514 may include a matching pair of one or more ALD and plasma-enhanced ALD processing stations. Although the depicted processing chamber 514 includes 4 stations, it is to be understood that the processing chamber described in accordance with the present disclosure may have any suitable number of stations. For example, in some embodiments, the processing chamber may have 5 or more stations, while in other embodiments, the processing chamber may have 3 or fewer stations.

[0105] Figure 5 One embodiment of a wafer handling system 590 for transferring wafers within the processing chamber 514 is depicted. In some embodiments, the wafer handling system 590 can transfer wafers between various processing stations and / or between a processing station and a load lock. It should be understood that any suitable wafer handling system can be used. Non-limiting examples include a wafer turntable and a robot for handling wafers. Figure 5Also depicted is one embodiment of a system controller 550 for controlling process conditions and hardware states of the processing tool 500. The system controller 550 may include one or more memory devices 556, one or more mass storage devices 554, and one or more processors 552. The processor 552 may include a computer or CPU, analog and / or digital input / output connections, a stepper motor controller board, etc.

[0106] In some embodiments, the system controller 550 controls all activities of the processing tool 500. The system controller 550 executes system control software 558 stored in the mass storage device 554, loaded into the memory device 556, and executed by the processor 552. Alternatively, the control logic can be hard-coded in the controller 550. Application-specific integrated circuits, programmable logic devices (e.g., field programmable gate arrays, or FPGAs), etc. can be used for these purposes. In the following discussion, whether "software" or "code" is used, functionally equivalent hard-coded logic can be used instead. The system control software 558 can include instructions for controlling timing, mixing of gases, gas flow rates, chamber and / or station pressures, chamber and / or station temperatures, wafer temperatures, target power levels, RF power levels, substrate pedestals, chuck and / or pedestal positions, and other parameters of specific processing performed by the processing tool 500. The system control software 558 can be configured in any appropriate manner. For example, various processing tool component subroutines or control objects can be written to control the operation of processing tool components used to perform various processing tool processes. The system control software 558 may be coded in any suitable computer readable programming language.

[0107] In some embodiments, the system control software 558 may include input / output control (IOC) sequencing instructions for controlling the various parameters described above. Other computer software and / or programs associated with the system controller 550 and stored in the mass storage device 554 and / or the memory device 556 may be employed in some embodiments. Examples of programs or program segments for this purpose include substrate positioning programs, process gas control programs, pressure control programs, heater control programs, and plasma control programs.

[0108] The substrate positioning program may contain program code for processing tool components used to load a substrate onto the pedestal 518 and control the spacing between the substrate and other parts of the processing tool 500.

[0109] The process gas control program may include code for controlling gas composition (e.g., a blocker gas such as an alkylaminosilane or alkylchlorosilane, a metal precursor gas, an oxygen-containing gas, a carrier gas, and / or a sweep gas as described herein) and flow rate and optionally code for flowing the gas into one or more process stations prior to deposition to stabilize the pressure in the process station. The pressure control program may include code for controlling the pressure within a process station by adjusting, for example, a throttle valve in an exhaust system of the process station, a gas flow into the process station, and the like.

[0110] The heater control program may contain code for controlling the flow of current to a heating unit used to heat the substrate.Alternatively, the heater control program may control the delivery of a heat transfer gas (such as helium) toward the substrate.

[0111] A plasma control program may include code for setting RF power levels applied to process electrodes within one or more process stations according to embodiments herein.

[0112] The pressure control program may include code for maintaining the pressure within the reaction chamber according to embodiments herein.

[0113] In some embodiments, there may be a user interface associated with the system controller 550. The user interface may include a display screen, a graphical software display of apparatus and / or process conditions, and user input devices such as a pointing device, keyboard, touch screen, microphone, and the like.

[0114] In some embodiments, the parameters adjusted by the system controller 550 may relate to process conditions. Non-limiting examples include process gas composition and flow rate, temperature, pressure, plasma conditions (e.g., RF bias power level), etc. These parameters may be provided to the user in the form of a recipe, which may be entered using the user interface.

[0115] Signals for monitoring the process may be provided from various process tool sensors by analog and / or digital input connections of the system controller 550. Signals for controlling the process may be output via analog and digital output connections of the process tool 500. Non-limiting examples of process tool sensors that may be monitored include mass flow controllers, pressure sensors (e.g., manometers), thermocouples, etc. Appropriately programmed feedback and control algorithms may be used with the data from these sensors to maintain process conditions.

[0116] The system controller 550 may provide program instructions for performing the above-described deposition process. The program instructions may control various process parameters, such as DC power level, RF bias power level, pressure, temperature, etc. The instructions may control these parameters to operate the in-situ deposition of the film stack according to the various embodiments described herein.

[0117] The system controller 550 will typically include one or more memory devices and one or more processors configured to execute instructions so that the apparatus will perform the methods described in accordance with the disclosed embodiments. A machine-readable medium containing instructions for controlling processing operations in accordance with the disclosed embodiments may be coupled to the system controller 550.

[0118] In some implementations, the system controller 550 is part of a system, which can be part of the above examples. Such a system can include a semiconductor processing device, which includes one or more processing tools, one or more processing chambers, one or more platforms for processing, and / or specific processing components (wafer pedestals, gas flow systems, etc.). These systems can be integrated with electronic devices for controlling their operation before, during, and after processing semiconductor wafers or substrates. The electronic device can be referred to as a "controller", which can control various elements or subcomponents of one or more systems. Depending on the processing requirements and / or the type of system, the system controller 550 can be programmed to control any process disclosed herein, including controlling process gas delivery, temperature settings (e.g., heating and / or cooling), pressure settings, vacuum settings, power settings, radio frequency (RF) generator settings, RF matching circuit settings, frequency settings, flow rate settings, fluid delivery settings, position and operation settings, wafer transfer in and out of tools and other transfer tools and / or load locks connected to or connected to a specific system through an interface.

[0119] In a broad sense, the system controller 550 can be defined as an electronic device with various integrated circuits, logic, memory and / or software that receives instructions, issues instructions, controls operations, enables cleaning operations, enables endpoint measurements, etc. The integrated circuit can include a chip in the form of firmware that stores program instructions, a digital signal processor (DSP), a chip defined as an application specific integrated circuit (ASIC), and / or one or more microprocessors or microcontrollers that perform program instructions (e.g., software). The program instructions can be instructions transmitted to the system controller 550 in the form of various separate settings (or program files) that define operating parameters for performing specific processing on or for a semiconductor wafer or system. In some embodiments, the operating parameters can be part of a recipe defined by a process engineer for completing one or more processing steps during the preparation of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or dies of a wafer.

[0120] In some implementations, the system controller 550 may be part of or coupled to a computer that is integrated with, coupled to, or connected to the system via a network, or a combination thereof. For example, the system controller 550 may be in the "cloud" or all or part of a fab host system, thereby allowing remote access to wafer processing. The computer may enable remote access to the system to monitor the current progress of a manufacturing operation, examine the history of past manufacturing operations, examine trends or performance criteria for multiple manufacturing operations, to change parameters of a current process, set processing steps to follow a current process, or start a new process. In some examples, a remote computer (e.g., a server) may provide a process recipe to the system via a network, which may include a local network or the Internet. The remote computer may include a user interface that allows input or programming of parameters and / or settings, which are then transmitted from the remote computer to the system. In some examples, the system controller 550 receives instructions in the form of data that specify parameters for each processing step to be performed during one or more operations. It should be understood that the parameters may be specific to the type of process to be performed and the type of tool to which the system controller 550 is configured to connect or control. Thus, as described above, the system controller 550 can be distributed, for example, by including one or more discrete controllers that are networked together and work toward a common goal (e.g., the processes and controls described herein). An example of a distributed controller for these purposes can be one or more integrated circuits on the chamber that communicate with one or more remote integrated circuits (e.g., at a platform level or as part of a remote computer) that are combined to control the processes within the chamber.

[0121] Example systems may include, but are not limited to, plasma etch chambers or modules, deposition chambers or modules, spin cleaning chambers or modules, metal plating chambers or modules, cleaning chambers or modules, chamfer edge etch chambers or modules, physical vapor deposition (PVD) chambers or modules, chemical vapor deposition (CVD) chambers or modules, ALD chambers or modules, atomic layer etch (ALE) chambers or modules, ion implantation chambers or modules, track chambers or modules, and any other semiconductor processing system that may be associated with or used in the preparation and / or manufacture of semiconductor wafers.

[0122] As described above, depending on one or more process steps to be performed by the tool, the system controller 550 can communicate with one or more other tool circuits or modules, other tool components, combination tools, other tool interfaces, adjacent tools, adjacent tools, tools located throughout the factory, a host computer, another controller, or tools used in material handling to move containers of wafers to and from tool locations and / or load ports in a semiconductor manufacturing facility.

[0123] Suitable apparatus for performing the methods disclosed herein are further discussed and described in U.S. patent application Ser. No. 13 / 084,399, filed on April 11, 2011, entitled “PLASMA ACTIVATED CONFORMAL FILM DEPOSITION” (now U.S. Patent No. 8,728,956); U.S. patent application Ser. No. 13 / 084,305, filed on April 11, 2011, entitled “SILICON NITRIDE FILMS AND METHODS,” each of which is incorporated herein in its entirety.

[0124] The apparatus / processes described herein can be used in conjunction with photolithographic patterning tools or processes, e.g., for preparing or manufacturing semiconductor devices, displays, LEDs, photovoltaic panels, etc. Typically, though not necessarily, these tools / processes will be used or operated together in a common manufacturing facility. Photolithographic patterning of films typically involves some or all of the following operations, each of which enables multiple available tools: (1) applying photoresist on a workpiece (i.e., substrate) using a spin coating or spray coating tool; (2) curing the photoresist using a hot plate or oven or UV curing tool; (3) exposing the photoresist to visible light or ultraviolet light or x-rays using a tool such as a wafer stepper; (4) developing the resist to selectively remove the resist and thereby pattern it using a tool such as a wet bench; (5) transferring the resist pattern to an underlying film or workpiece by using a dry or plasma assisted etching tool; and (6) removing the resist using a tool such as an RF or microwave plasma resist stripper.

[0125] experiment

[0126] Experiment 1

[0127] An experiment was conducted to compare deposition growth on blocked and unblocked tungsten and silicon oxide surfaces of a substrate. Zirconium oxide was deposited using ALD on a tungsten surface that was not exposed to dimethyldichlorosilane, and the number of deposition cycles and thickness are plotted as solid dots and solid lines on the graph. Fig. 6A Zirconium oxide was deposited by ALD on a tetraethyl orthosilicate-based silicon oxide surface that was not exposed to dimethyldichlorosilane, and the number of deposition cycles and thickness are plotted as open points and dashed lines on Fig. 6A As shown in the figure, the growth trends of the two films are similar and both grow at approximately the same rate.

[0128] Next, the tungsten substrate was first exposed to dimethyldichlorosilane and then to the same Fig. 6AThe ALD cycles in the above diagram deposited zirconium oxide on a tungsten substrate that had been exposed to dimethyldichlorosilane. The number of cycles and thickness deposited are plotted as solid points and solid lines on the Figure 6B Similarly, the silicon oxide substrate is first exposed to dimethyldichlorosilane and then to the same Fig. 6A The ALD cycles in the above diagram deposited zirconium oxide on a silicon oxide substrate that had been exposed to dimethyldichlorosilane. The number of cycles and thickness deposited are plotted as open points and dashed lines on the Figure 6B As shown in the figure, the growth of the two films is similar to each other, and both surfaces grow at approximately the same rate, but compared to Fig. 6A For both surfaces, the overall deposition thickness was significantly smaller—indeed, there was very little, if any, deposition on either substrate exposed to dimethyldichlorosilane during the first 10 ALD cycles. Even at 30 ALD cycles, the zirconium oxide thickness remained less than 10. These results indicate that dimethyldichlorosilane inhibits deposition on both tungsten and silicon oxide surfaces alike.

[0129] The substrate with the exposed tungsten surface was exposed to dimethyldichlorosilane and then Fig. 6A The ALD cycle was used to deposit zirconium oxide before immersion in water. The number of cycles and thickness of deposition are plotted as solid points and solid lines on Figure 7 In addition, the substrate having the exposed silicon oxide surface was exposed to dimethyldichlorosilane and then Fig. 6A The ALD cycle was used to deposit zirconium oxide before immersion in water. The number of cycles and thickness of deposition are plotted as open points and dashed lines. Figure 7 In. Figure 7 As shown in , the initiation of zirconium oxide deposition occurs faster on tungsten surfaces than on silicon oxide surfaces. In addition, the growth of the zirconium oxide deposition is similar to that on Fig. 6A This indicates that the immersion step in the water bath removes the inhibitor from the tungsten surface, allowing zirconium oxide to be deposited. At the same time, the growth of silicon oxide is similar to that in Figure 6B This indicates that the immersion step in the water bath did not remove the inhibitor from the silicon oxide surface and therefore the silicon oxide surface remained blocked and less zirconium oxide was deposited on it. These results indicate the feasibility of using dimethyldichlorosilane as a blocking agent to allow selective deposition on tungsten surfaces relative to silicon oxide surfaces.

[0130] in conclusion

[0131] Although the above embodiments have been described in some detail for the purpose of clarity of understanding, it is apparent that certain variations and modifications may be implemented within the scope of the appended claims. It should be noted that there are many alternative ways of implementing the processes, systems and devices of the embodiments of the present invention. Therefore, the embodiments of the present invention should be considered illustrative rather than restrictive, and the embodiments are not limited to the details given herein.

Claims

1. A method for selectively depositing a metal oxide on an exposed metal surface relative to a dielectric material on a substrate, the method comprising: (a) providing the substrate comprising the dielectric material and the exposed metal surface; (b) exposing the substrate to a blocking agent prior to depositing the metal oxide to non-selectively adsorb the blocking agent on both the dielectric material and the exposed metal surface, wherein the blocking agent forms a hydrolyzable bond with the exposed metal surface but does not form a hydrolyzable bond with the dielectric material; (c) selectively removing the blocking agent from the exposed metal surface after exposing the substrate to the blocking agent and before depositing the metal oxide; as well as (d) depositing the metal oxide selectively on the exposed metal surface relative to the dielectric material on the substrate. 2 . The method of claim 1 , wherein selectively removing the blocking agent is performed by contacting the substrate with water. The method according to claim 1 , wherein selectively removing the blocking agent is performed by immersing the substrate in water. The method of claim 1 , wherein the blocking agent is silamide. The method according to claim 4 , wherein the blocking agent is an alkylchlorosilane.

6. The method according to claim 5, wherein the alkylchlorosilane has a chemical structure Cl x Si([CH3(CH2) y ]) (4-x) , where x is an integer between 1 and 3, inclusive, and y is an integer greater than or equal to 1. The method of claim 4 , wherein the blocking agent is an alkylaminosilane.

8. The method of claim 7, wherein the alkylaminosilane has a chemical structure [(CH3)2N] x Si([CH3(CH2) y ]) (4-x) , where x is an integer between 1 and 3, inclusive, and y is an integer greater than or equal to 1.

9. The method of claim 1, wherein the blocking agent is provided in an aprotic polar solvent.

10. The method of claim 1, wherein the substrate is exposed to the blocking agent by immersing the substrate in a wet solution of the blocking agent.

11. The method of claim 10, wherein the substrate is exposed to the blocking agent at a temperature between 25°C and 100°C.

12. The method of claim 11, wherein the substrate is exposed to the blocking agent at a temperature between 60°C and 100°C.

13. The method of claim 1, wherein the substrate is exposed to the blocking agent by introducing the blocking agent in a vapor phase.

14. The method of claim 13, wherein the substrate is exposed to the blocking agent at a temperature between 100°C and 300°C.

15. The method of claim 14, wherein the substrate is exposed to the blocking agent at a temperature between 200°C and 250°C.

16. The method of claim 1, wherein the substrate is exposed to the blocking agent for a duration between 10 seconds and 60 seconds.

17. The method of claim 1, wherein selectively removing the blocking agent is performed at room temperature.

18. The method of claim 1, wherein selectively removing the blocking agent selectively hydrolyzes bonds between the blocking agent and the exposed metal surface.

19. The method of claim 1, wherein the metal oxide is aluminum oxide.

20. The method of claim 1, wherein the metal oxide is deposited selectively on the exposed metal surface relative to the dielectric material using atomic layer deposition.

21. The method of claim 1, wherein the exposed metal surface comprises a metal selected from the group consisting of tungsten, titanium, and aluminum.

22. The method of claim 1, wherein the dielectric material comprises silicon.

23. The method of claim 22, wherein the dielectric material is selected from the group consisting of silicon oxide, silicon nitride, and carbon-doped silicon oxide.

24. The method of claim 1, wherein the substrate is patterned.

25. The method of claim 1, wherein hydrolysis results in the exposed metal surface having a hydrogen-terminated and / or hydroxyl-terminated surface.

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