Low resistivity films containing molybdenum

Abstract

To provide low resistance metallization stack structures for logic and memory applications, and related methods of fabrication.SOLUTION: In some implementations, the methods include the steps of: providing a tungsten (W)-containing layer on a substrate; and depositing a molybdenum (Mo)-containing layer on the W-containing layer. In some implementations, the methods include a step of depositing a Mo-containing layer directly on a dielectric or titanium nitride (TiN) layer without an intervening W-containing layer.SELECTED DRAWING: Figure 2

Description

Background Art

[0001] [Cross - Reference to Related Applications] This application claims the benefit of U.S. Provisional Patent Application No. 62 / 483,857, filed on April 10, 2017, under 35 U.S.C. § 119, and that provisional patent application is incorporated herein by reference.

[0002] The description of the background art provided herein is for the purpose of generally presenting the background of the disclosure. The achievements of the inventors named herein, to the extent described in this background art, are not to be regarded as prior art to the disclosure, either explicitly or implicitly, including aspects of the description that cannot be regarded as prior art at the time of filing in the scope described in this background art.

[0003] Tungsten (W) film deposition using chemical vapor deposition (CVD) technology is an essential part of semiconductor manufacturing processes. For example, tungsten films can be used as low - resistance electrical connections in the form of horizontal interconnects, vias between adjacent metal layers, and contacts between a first metal layer on a silicon substrate and a device. Also, tungsten films can be used in various memory applications (such as the formation of buried word line (bWL) architectures for dynamic random access memory (DRAM)) and logic applications. In an example of bWL deposition, a tungsten layer can be deposited on a titanium nitride (TiN) barrier layer to form a TiN / W bilayer by CVD processing using WF 6 However, the continuous reduction in feature size and film thickness has brought various problems to the TiN / W film stack. These include the high resistivity of thinner films and the degradation of TiN barrier properties.

Summary of the Invention

[0004] One aspect of the present disclosure relates to a method comprising providing a tungsten (W)-containing layer on a substrate and depositing a molybdenum (Mo)-containing layer on the W-containing layer. In some embodiments, the W-containing layer is a WCN layer. In some embodiments, the W-containing layer is a W nucleation layer. In some embodiments, the W-containing layer is deposited from one or more tungsten chloride precursors. In some embodiments, the Mo-containing layer is a Mo layer having less than 1 atomic % impurities. In some embodiments, the method comprises the step of thermally annealing the Mo-containing layer. In some embodiments, the Mo-containing layer is deposited by exposing the W-containing layer to a reducing agent and a Mo-containing precursor selected from molybdenum hexafluoride (MoF 6 ), molybdenum pentachloride (MoCl 5 ), molybdenum dichloride dioxide (MoO 2 Cl 2 ), molybdenum oxychloride (MoOCl 4 ), and molybdenum hexacarbonyl (Mo(CO) 6 ). In some embodiments, the substrate temperature during exposure to the Mo-containing precursor is less than 550 °C. In some embodiments, the substrate is exposed to the reducing agent at a first substrate temperature and to the Mo-containing precursor at a second substrate temperature, and the first substrate temperature is lower than the second substrate temperature. In some embodiments, the reducing agent is a mixture of a boron-containing reducing agent and a silicon-containing reducing agent.

[0005] Another aspect of the present disclosure relates to a method comprising flowing a reducing agent gas into a processing chamber containing a substrate at a first substrate temperature to form a conformal reducing agent layer on the substrate, and exposing the conformal reducing agent layer to a molybdenum (Mo)-containing precursor at a second substrate temperature to convert the reducing agent layer to molybdenum. In some embodiments, the first substrate temperature is lower than the second substrate temperature. In some embodiments, the reducing agent is a mixture of a boron-containing reducing agent and a silicon-containing reducing agent. In some embodiments, the first substrate temperature is 400 °C or lower and the second substrate temperature is 500 °C or higher. In some embodiments, the method further comprises the step of annealing the molybdenum.

[0006] Another aspect of the present disclosure is a process of pulse-supplying a reducing agent, where the reducing agent contains boron (B), silicon (Si), or germanium (Ge), and a process of pulse-supplying a Mo-containing precursor, where the Mo-containing precursor is reduced by the reducing agent or a product of the reducing agent to form a multi-component tungsten-containing film containing one or more of B, Si, and Ge on a substrate. In some embodiments, the multi-component tungsten-containing film contains 5% to 60% (atomic %) of B, Si, or Ge. In some embodiments, 5% to 60% (atomic %) of B, Si, or Ge is supplied by the reducing agent.

[0007] Another aspect of the present disclosure is an apparatus for performing the methods disclosed herein. These features and other features will be further discussed with reference to the drawings.

Brief Description of the Drawings

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DETAILED DESCRIPTION OF THE INVENTION

[0018] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the presented embodiments. The disclosed embodiments may be practiced without some or all of these specific details. Also, in order to avoid obscuring the disclosed embodiments needlessly, detailed descriptions of well-known processing operations are omitted. It is to be understood that the disclosed embodiments are described in relation to specific embodiments, but are not intended to be limiting thereof.

[0019] Provided herein is a low-resistance metallization stack structure for logic and memory applications. FIGS. 1A and 1B are schematic examples of material stacks including molybdenum (Mo) according to various embodiments. FIGS. 1A and 1B show the order of materials in a particular stack and may be used in any suitable architecture and application, as will be described in more detail later with respect to FIGS. 2 and 3. In the example of FIG. 1A, substrate 102 has a Mo layer 108 deposited thereon. Substrate 102 may be a silicon or other semiconductor wafer, such as a 200 mm wafer, a 300 mm wafer, or a 450 mm wafer, and may include a wafer having one or more material layers, such as a dielectric material, a conductive material, or a semiconductor material, deposited thereon. The method may also be applied to form a metallization stack structure on other substrates (glass, plastic, etc.).

[0020] In FIG. 1A, dielectric layer 104 is on substrate 102. Dielectric layer 104 may be deposited directly on the semiconductor (e.g., Si) surface of substrate 102, or any number of intermediate layers may be present. Examples of dielectric layers include doped and undoped silicon oxide, silicon nitride, and aluminum oxide layers, and specific examples include doped or undoped layer SiO 2 and Al 2 O 3include. Also, in FIG. 1A, a diffusion barrier layer 106 is disposed between the Mo layer 108 and the dielectric layer 104. Examples of diffusion barrier layers include titanium nitride (TiN), titanium / titanium nitride (Ti / TiN), tungsten nitride (WN), and tungsten carbonitride (WCN). Further examples of diffusion barriers are multi-component Mo-containing films, as will be detailed later. The Mo layer 108 is the main conductor of the structure. As will be detailed later, the Mo layer 108 may include a Mo nucleation layer and a bulk Mo layer. Further, in some embodiments, the Mo layer 108 may be deposited on a tungsten (W) or W-containing growth initiation layer.

[0021] FIG. 1B shows another example of a material stack. In this example, the stack includes a substrate 102 and a dielectric layer 104, with the Mo layer 108 deposited on the dielectric layer 104 and no diffusion barrier layer in between. As in the example of FIG. 1A, the Mo layer 108 may comprise a Mo nucleation layer and a bulk Mo layer, and in some embodiments, the Mo layer 108 may be deposited on a tungsten (W) or W-containing growth initiation layer. By using Mo, which has a lower electron mean free path than W, as the main conductor, a thinner film with lower resistance can be obtained.

[0022] FIGS. 1A and 1B show examples of metallization stacks, but the methods and resulting stacks are not so limited. For example, in some embodiments, Mo may be deposited directly on a Si or other semiconductor substrate, with or without a W initiation layer.

[0023] The material stack described above and further described below may be used in various embodiments. FIGS. 2, 3A, and 3B provide examples of structures in which a Mo-containing stack may be utilized. FIG. 2 shows a schematic example of a DRAM architecture with a Mo-embedded word line (bWL) 208 within a silicon substrate 202. The Mo bWL is formed within a trench etched into the silicon substrate 202. The lining of the trench is a conformal barrier layer 206 and an insulating layer 204 disposed between the conformal barrier layer 206 and the silicon substrate 202. In the example of FIG. 2, the insulating layer 204 may be a gate oxide layer formed from a high-k material such as a silicon oxide or silicon nitride material. In some embodiments disclosed herein, the conformal barrier layer is a TiN or tungsten-containing layer. In some embodiments, when TiN is used as the barrier, a conformal tungsten-containing growth initiation layer may be present between the conformal barrier layer 206 and the Mo bWL 208. Alternatively, the Mo bWL 208 may be deposited directly on top of the TiN or other diffusion layer.

[0024] FIG. 3A shows a schematic example of a Mo word line 308 within a 3D NAND structure 323. FIG. 3B shows a 2D rendering of a 3D feature of a 3D NAND structure during manufacturing after Mo filling, including the word line 308 and the conformal barrier layer 306. FIG. 3B is a cross-sectional view of the filled region, and the pillar constriction 324 shown in the figure represents a constriction as seen in a plan view rather than in the cross-sectional view. The conformal barrier layer 306 may be a TiN or tungsten-containing layer, as described above with respect to the conformal barrier layer 206 of FIG. 2. In some embodiments, the tungsten-containing film may function as a barrier layer and a nucleation layer for subsequent CVD Mo deposition, as described below. When TiN is used as the barrier, a conformal tungsten-containing growth initiation layer may be present between the barrier and the word line. Alternatively, the Mo word line 308 may be deposited directly on top of the TiN or other diffusion layer.

[0025] Methods of forming Mo-containing stacks include deposition techniques such as chemical vapor deposition (CVD) and pulse nucleation layer (PNL) deposition. In PNL technology, co-reactants, optional purge gases, and pulses of Mo-containing precursors are sequentially injected into and purged from the chamber. The process is repeated cyclically until the desired thickness is achieved. PNL generally embodies any cyclic process that adds reactants sequentially for reaction on a semiconductor substrate, such as atomic layer deposition (ALD) technology. PNL may be used for depositing Mo nucleation layers and / or W-based growth initiation layers in the methods described herein. The nucleation layer is typically a thin conformal layer that facilitates subsequent deposition of bulk material thereon. According to various embodiments, the nucleation layer may be deposited before any filling of features and / or at a later point during filling of features.

[0026] PNL techniques for depositing tungsten nucleation layers are described in U.S. Pat. Nos. 6,635,965; 7,005,372; 7,141,494; 7,589,017; 7,772,114; 7,955,972; and 8,058,170. The thickness of the nucleation layer may depend on the nucleation layer deposition method and the desired quality of the bulk deposition. Generally, the thickness of the nucleation layer is sufficient to assist in high-quality uniform bulk deposition. By way of example, it may be in the range of 10 Å to 100 Å.

[0027] In many embodiments, deposition of the Mo bulk layer may be performed by a CVD process in which a reducing agent and a Mo-containing precursor are flowed into the deposition chamber to deposit a bulk layer within the features. An inert carrier gas may be used to supply one or more of the reactant streams, which may or may not be pre-mixed. Unlike PNL or ALD processes, this operation generally involves flowing reactants continuously until the desired amount is deposited. In certain embodiments, the CVD operation may be performed in multiple stages, with multiple periods in which reactants flow continuously and simultaneously separated by periods in which the flow of one or more reactants is diverted.

[0028] The Mo-containing precursor includes molybdenum hexafluoride (MoF 6 ), molybdenum pentachloride (MoCl 5 ), molybdenum dichloride dioxide (MoO 2 Cl 2 ), molybdenum oxychloride (MoOCl 4 ), and molybdenum hexacarbonyl (Mo(CO) 6 ). Organometallic precursors (such as molybdenum silyl cyclopentadienyl and molybdenum silyl allyl complexes) may be used. The Mo-containing precursor may be a halogen compound precursor, which includes MoF 6 and MoCl 5 and a mixed halogen compound precursor having two or more halogens capable of forming a stable molecule. An example of the mixed halogen compound precursor is MoCl x Br y that can form a stable molecule, where x and y are any numbers greater than 0.

[0029] Mo-containing layer on the W-based growth initiation layer In certain embodiments, a structure including a molybdenum (Mo)-containing layer on a tungsten (W)-based growth initiation layer is provided. A method for forming the Mo-containing film is also provided.

[0030] The W-based growth initiation layer may be any W-containing layer. In some embodiments, it is a nucleation layer, i.e., a thin conformal layer that functions to facilitate the subsequent formation of the bulk material thereon. In some embodiments, the W-based growth initiation layer is a bulk W-containing layer, and the bulk W-containing layer itself may be deposited on the nucleation layer. When used for feature filling, the nucleation layer may be deposited to conformally coat the sidewalls and bottom of the feature. Conforming to the bottom and sidewalls of the underlying features can be important to assist in high-quality deposition. According to various embodiments, the W-based growth initiation layer may be deposited by one or both of PNL and CVD processes. For example, a CVD layer may be deposited on a PNL layer.

[0031] In some embodiments, the W-containing layer is an elemental W layer. Such a layer may be deposited by any suitable method including PNL or CVD methods. Elemental W is distinguished from two-component films such as WC or WN and three-component films such as WCN, but may contain some amount of impurities. It may be referred to as a W layer or a W film.

[0032] In some embodiments, the W-based growth layer is a low-resistance W (LRW) film. The deposition of low-resistance tungsten according to certain embodiments is described in U.S. Patent No. 7,772,114. In particular, the '114 patent describes exposing a PNL W nucleation layer to a reducing agent prior to CVD deposition of W onto the PNL W layer. The LRW film has a large particle size that provides a good template for large Mo particle growth.

[0033] In some embodiments, the W-based growth layer is a PNL W nucleation layer deposited using one or more of a boron-containing reducing agent (e.g., B 2 H 6 ) or a silicon-containing reducing agent (e.g., SiH 4 ) as a co-reactant. For example, one or more S / W cycles (where S / W means that a pulse of silane is followed by a pulse of tungsten hexafluoride (WF 6 ) or other tungsten-containing precursor) may be used to deposit a PNL W nucleation layer on which a Mo layer is deposited. In another example, one or more B / W cycles (where B / W means that a pulse of diborane is followed by a pulse of WF 6 or other tungsten-containing precursor) may be used to deposit a PNL W nucleation layer on which a Mo layer is deposited. Both B / W and S / W cycles may be used to deposit the PNL W nucleation layer. Examples of PNL processes using one or both of a boron-containing reducing agent and a silicon-containing reducing agent are described in U.S. Patent Nos. 7,262,125; 7,589,017; 7,772,114; 7,955,972; 8,058,170; 9,236,297; and 9,583,385.

[0034] In some embodiments, the W-based growth layer is a W layer or other W-containing layer deposited using a tungsten chloride (WCl 6 ) or tungsten pentachloride (WCl 5 ) precursor such as tungsten chloride (WCl x ). Deposition of the W-containing layer using tungsten chloride is described in U.S. Patent No. 9,595,470; U.S. Patent Publication No. 20150348840; and U.S. Patent Application No. 15 / 398,462.

[0035] In some embodiments, the W-based growth layer is a low-fluorine W layer. U.S. Patent No. 9,613,818 describes a sequential CVD method for depositing a low-fluorine W layer. U.S. Patent Publication No. 2016 / 0351444 describes a PNL method for depositing a low-fluorine W layer.

[0036] In some embodiments, the W-based growth layer is a WN, WC, or WCN film. Methods for depositing one or more of WN, WC, or WCN are described in each of U.S. Patent Nos. 7,005,372; 8,053,365; 8,278,216; and U.S. Patent Application No. 15 / 474,383.

[0037] The W-based growth layer is not limited to the above examples and may be any W film or other W-containing film deposited by any suitable method such as ALD, PNL, CVD, or physical vapor deposition (PVD) methods. ALD, PNL, and CVD depositions involve exposure to a W-containing precursor. WF 6 and WCl x In addition to the precursors, examples of W-containing precursors include tungsten hexacarbonyl (W(CO) 6 ) and organometallic precursors such as MDNOW (methylcyclopentadienyl-dicarbonyl-nitrosyl-tungsten) and EDNOW (ethylcyclopentadienyl-dicarbonyl-nitrosyl-tungsten). In many ALD, PNL, and CVD deposition processes, a reducing agent is used to reduce the W-containing precursor. Examples include hydrogen gas (H 2) Silane (SiH 4 ) Disilane (Si 2 H 6 ) Hydrazine (N 2 H 4 ) Diborane (B 2 H 6 ) and germane (GeH 4 ) are included.

[0038] Also, as described above, depending on the specific precursors and processes used, the W-containing films described herein may contain some amounts of other compounds, dopants, and / or impurities such as nitrogen, carbon, oxygen, boron, phosphorus, sulfur, silicon, germanium, etc. The tungsten content in the film can range from 20% to 100% (atomic) tungsten. In many examples, the thin film is tungsten-rich and contains at least 50% (atomic) tungsten, or at least about 60%, 75%, 90%, or 99% (atomic) tungsten. In some examples, the film may be a mixture of elemental tungsten (W) and other tungsten-containing compounds (such as WC, WN, etc.).

[0039] The Mo-containing film may be deposited on the W-based growth initiation layer by any suitable method such as ALD or CVD. In some embodiments, sequential CVD processing may be used. Sequential CVD processing is described in U.S. Patent No. 9,613,818, which patent is incorporated herein by reference.

[0040] The deposition of the Mo-containing film may include exposing the W-based growth initiation layer to a Mo-containing precursor and a reducing agent or other co-reactant simultaneously or sequentially. Examples of Mo-containing precursors include MoF 6 , MoCl 5 , MoOCl 4 , and Mo(CO) 6 . Organometallic precursors (such as molybdenum silyl cyclopentadienyl and molybdenum silyl allyl complexes) may be used. The purity of the Mo film (measured, for example, by the O content) can be adjusted by varying the partial pressures of the precursor and the co-reactant.

[0041] The substrate temperature during Mo evaporation can be between 300 °C and 750 °C, and in certain embodiments, can be between 450 °C and 550 °C. The substrate temperature is determined by the thermal budget and the evaporation chemical substances. The thermal budget is determined by the application, and a high evaporation temperature may not be a problem for memory applications, but may exceed the thermal budget for logic applications.

[0042] The presence of a W-containing growth initiation layer enables the execution of evaporation at a lower temperature. For example, Mo evaporation from MoCl 5 or MoOCl 4 cannot be carried out at a temperature below 550 °C due to the strength of the Mo-Cl bond. However, with a W-containing growth initiation layer, evaporation can be carried out at a temperature below 550 °C. The chamber pressure during Mo evaporation can be, for example, between 5 Torr and 60 Torr.

[0043] In some embodiments, instead of a stronger reducing agent (such as SiH 4 or B 2 H 6 ), H 2 is used as the reducing agent. These stronger reducing agents can cause an undesirable oxygen-rich interface when using an oxygen-containing Mo-containing precursor. The Mo-containing film may be an elemental Mo film, but such a film may contain some amount of other compounds, dopants, and / or impurities depending on the specific precursor and process used.

[0044] Mo-containing layer on the PNL-evaporated Mo nucleation layer In certain embodiments, the Mo-containing layer may be evaporated without using a W-based growth initiation layer. For example, an elemental Mo layer may be evaporated on TiN or a dielectric layer. For certain precursors, the evaporation temperature may be relatively high (above 550 °C) to obtain evaporation. Chlorine-containing precursors (MoOCl 5 , MoOCl 4 , and MoO 2 Cl 2CVD deposition using, for example, the above may be performed on the TiN and dielectric surfaces at temperatures higher than 550°C. At lower temperatures, CVD deposition may be performed on any surface using the W-based growth initiation layer as described above. Further, in some embodiments, CVD deposition may be performed on any surface using a Mo-containing nucleation layer deposited by the PNL process.

[0045] As described above, in the PNL process, a co-reactant, an optional purge gas, and a pulse of a Mo-containing precursor are sequentially injected into the chamber and then purged therefrom. In some embodiments, the Mo nucleation layer is deposited using one or more of a boron-containing reducing agent (e.g., B 2 H 6 ) or a silicon-containing reducing agent (e.g., SiH 4 ) as a co-reactant. For example, one or more S / Mo cycles (where S / Mo means that a pulse of a Mo-containing precursor follows a pulse of silane) may be used to deposit a PNL Mo nucleation layer on which a CVD Mo layer is deposited. In another example, one or more B / Mo cycles (where B / Mo means that a pulse of a Mo-containing precursor follows a pulse of diborane) may be used to deposit a PNL Mo nucleation layer on which a CVD Mo layer is deposited. Both B / Mo and S / Mo cycles may be used to deposit a PNL Mo nucleation layer (e.g., x(B / Mo)+y(S / Mo), where x and y are integers). For PNL deposition of the Mo nucleation layer, in some embodiments, the Mo-containing precursor may be an oxygen-free precursor (e.g., MoF 6 or MoCl 5 ). Oxygen in the oxygen-containing precursor may react with the silicon-containing or boron-containing reducing agent to form impure high-resistance films of MoSi x O y or MoB x O y . The oxygen-containing precursor may be used with minimal oxygen incorporation. In some embodiments, H 2may be used as a reducing gas instead of a boron-containing or silicon-containing reducing gas. An example of the thickness of the deposition of the Mo nucleation layer ranges from 5 Å to 30 Å. The film at the lower limit of this range may not be continuous, but its thickness may be sufficient as long as it can help initiate continuous bulk Mo growth. In some embodiments, the reducing agent pulse may be made at a substrate temperature lower than that of the Mo precursor pulse. For example, when the Mo pulse is made at a temperature higher than 300 °C, B 2 H 6 or SiH 4 (or other boron-containing or silicon-containing reducing agent) pulse may be performed at a temperature lower than 300 °C.

[0046] Mo Deposition Using a Reducing Agent Layer Deposition at a lower temperature (less than 550 °C) may be performed directly on a non-W surface (such as a dielectric and TiN surface) by a process as shown in FIG. 4A. It may also be used on a W-containing surface. FIG. 4A provides a process flow chart of a method performed according to the disclosed embodiments. Operations 402-408 in FIG. 4A may be performed to form a conformal Mo layer directly on at least a dielectric surface or other surface.

[0047] In operation 402, the substrate is exposed to a reducing agent gas to form a reducing agent layer. In some embodiments, the reducing agent gas may be silane, borane, or a mixture of silane and diborane. Examples of silane include SiH 4 and Si 2 H 6 and examples of borane include diborane (B 2 H 6 ), and B n H n+4 , B n H n+6 , B n H n+8 , B n H m where n is an integer from 1 to 10 and m is an integer different from m. Other boron-containing compounds, such as alkyl boranes, alkyl borons, aminoboranes (CH 3 )2 NB(CH 2 ) 2 、 carborane (C 2 B n H n+2 , etc.) may also be used. In some embodiments, the reducing agent layer may include silicon or a silicon-containing material, phosphorus or a phosphorus-containing material, germanium or a germanium-containing material, boron or a boron-containing material, and combinations thereof, which can reduce the tungsten precursor. Further examples of reducing agent gases that can be used to form such layers are PH 3 , SiH 2 Cl 2 , and GeH 4 . According to various embodiments, hydrogen may or may not be flowed in the background. (Hydrogen can reduce the tungsten precursor, but does not function as a reducing agent in a gas mixture with a sufficient amount of stronger reducing agents such as silane and diborane).

[0048] In some embodiments, the reducing agent gas is a mixture containing a small amount of boron-containing gas such as diborane together with another reducing agent. The addition of a small amount of boron-containing gas can greatly affect the decomposition and adhesion coefficient of another reducing agent. Note that the substrate may be sequentially exposed to two reducing agents, for example, silane and diborane. However, flowing a mixed gas can facilitate the addition of a very small amount of minority gas (for example, the ratio of silane to diborane is at least 100:1). In some embodiments, a carrier gas may be flowed. In some embodiments, a carrier gas such as nitrogen (N 2 ), argon (Ar), helium (He), or other inert gas may be flowed during operation 402.

[0049] In some embodiments, the reducing agent layer may include elemental silicon (Si), elemental boron (B), elemental germanium (Ge), or mixtures thereof. For example, as described later, the reducing agent layer may include Si and B. The amount of B may be adjusted to achieve a high deposition rate of the reducing agent layer but a low resistivity. In some embodiments, the reducing agent layer may have, for example, boron between 5% and 80%, or boron between 5% and 50%, between 5% and 30%, or between 5% and 20%, and the remainder is basically composed of Si and in some cases H. Hydrogen atoms, for example, SiH x , BH y , GeH z , or mixtures thereof, are present, where x, y, and z may independently be between 0 and a number less than the stoichiometric equivalent of the corresponding reducing agent compound.

[0050] In some embodiments, the composition may vary through the thickness of the reducing agent layer. For example, the reducing agent layer may be 20% B at the bottom of the reducing agent layer and 0% B at the top of the layer. The total thickness of the reducing agent layer may be between 10 Å and 50 Å, and in some embodiments, between 15 Å and 40 Å, or between 20 Å and 30 Å. The reducing agent layer conformally lines the features.

[0051] The substrate temperature during operation 402 may be maintained at temperature T1 so that the film is conformal. If the temperature is too high, the film may not be conformal to the topography of the underlying structure. In some embodiments, a step coverage greater than 90% or 95% is achieved. For silane, diborane, and silane / diborane mixtures, the conformality is excellent at 300 °C and may decrease at temperatures above 400 °C. Thus, in some embodiments, the temperature during operation 202 is at most 350 °C, or at most 325 °C, at most 315 °C, or even at most 300 °C. In some embodiments, a temperature below 300 °C is used. For example, the temperature may be as low as about 200 °C.

[0052] Operation 402 may be performed over any suitable duration. In some examples, examples of the duration may include from about 0.25 seconds to about 30 seconds, from about 0.25 seconds to about 20 seconds, from about 0.25 seconds to about 5 seconds, or from about 0.5 seconds to about 3 seconds.

[0053] In operation 404, the chamber is optionally purged to remove any excess reducing agent that did not adsorb to the surface of the substrate. The purge may be performed by flowing an inert gas at a fixed pressure to reduce the pressure in the chamber and then repressurizing the chamber before starting another gas exposure. Examples of inert gases include nitrogen (N 2 ), argon (Ar), helium (He), and mixtures thereof. The purge may be performed over a duration of from about 0.25 seconds to about 30 seconds, from about 0.25 seconds to about 20 seconds, from about 0.25 seconds to about 5 seconds, or from about 0.5 seconds to about 3 seconds.

[0054] In operation 406, the substrate is exposed to a Mo-containing precursor at a substrate temperature T2. Examples of Mo-containing compounds have been described above and include chlorides and oxychlorides. The use of an oxygen-containing precursor can lead to impurity incorporation and higher resistivity. However, if oxygen is incorporated, a very thin and possibly discontinuous reducing agent layer may be used for an acceptable resistivity. In some embodiments, a carrier gas such as nitrogen (N 2 ), argon (Ar), helium (He), or other inert gas may be flowed during operation 406. An example of the temperature is from 500 °C to 700 °C.

[0055] Operation 406 may be performed over any suitable duration. In some embodiments, the operation may include a soak of the Mo-containing precursor and, in some embodiments, a sequence of Mo-containing precursor pulses. According to various embodiments, operation 406 may be performed in the presence or absence of H 2 . When H 2 is used, in some embodiments, H 2 and the Mo-containing precursor may be applied in an ALD-type mode. For example: H2 pulse argon purge background H 2 pulse of Mo-containing precursor, with or without argon purge repeatedly

[0056] The substrate temperature T2 is high enough for the Mo-containing precursor to react with the reducing agent layer to form elemental Mo. The entire reducing agent layer is converted to Mo. In some embodiments, the temperature is at least 450 °C and may be at least 550 °C to obtain 100% or nearly 100% conversion. The resulting feature is lined with a conformal film of Mo. It may be between 10 Å and 50 Å, and in some embodiments, may be between 15 Å and 40 Å, or between 20 Å and 30 Å. Generally, it is approximately the same thickness as the reducing agent layer. In some embodiments, it may be up to 5% thicker than the reducing agent layer due to volume expansion during conversion. In some embodiments, a CVD Mo layer may be deposited on the conformal Mo layer.

[0057] multi-component Mo film In some embodiments, a multi-component Mo-containing film is provided. In some such embodiments, the multi-component Mo-containing film may include one or more of boron (B), silicon (Si), or germanium (Ge). Figure 4B provides a process flow chart of a method performed in accordance with the disclosed embodiments.

[0058] First, the substrate is exposed to a reducing agent pulse (block 452). In some embodiments, the surface on which the reducing agent pulse is exposed to form a film thereon is a dielectric. According to various embodiments, the film may be formed on other types of surfaces including conductor surfaces and semiconductor surfaces.

[0059] The reducing agent used in block 452 reduces the Mo-containing precursor used in subsequent operations and provides a compound incorporated into the resulting film. Examples of such reducing agents include boron-containing, silicon-containing, and germanium-containing reducing agents. Examples of boron-containing reducing agents include boranes such as B n H n+4 、B n H n+6 、B n H n+8 、B n H m etc., where n is an integer from 1 to 10 and m is an integer different from m. In certain examples, diborane may be used. Other boron-containing compounds such as alkylboranes, alkylborons, aminoboranes (CH 3 ) 2 NB(CH 2 ) 2 、and carboranes (C 2 B n H n+2 etc.) may be used. Examples of silicon-containing compounds include silanes (SiH 4 and Si 2 H 6 etc.). Examples of germanium-containing compounds include germanes such as Ge n H n+4 、Ge n H n+ 6、Ge n H n+8 、and Ge n H m etc., where n is an integer from 1 to 10 and n is an integer different from m. Other germanium-containing compounds such as alkylgermanes, alkylgermaniums, aminogermanes, and carbogermanes may be used.

[0060] According to various embodiments, block 452 may include adsorbing a thin layer of pyrolyzed elemental boron, silicon, or germanium onto the surface of the substrate. In some embodiments, block 452 may include adsorbing precursor molecules onto the substrate surface.

[0061] Next, the chamber with the substrate disposed therein may be optionally purged (block 454). A purge pulse or evacuation can be used to remove any by-products and unadsorbed precursors, if present. Next, a pulse of the Mo-containing precursor follows (block 456). In some embodiments, the Mo-containing precursor is MoOCl 4 , MoO 2 Cl 2 , and Cl-containing precursors such as MoCl 5 . An optional purge (457) may be performed after block 456. The Mo-containing precursor is reduced by a reducing agent (or its decomposition or reaction products) to form a multi-component film.

[0062] The deposition cycle typically deposits a portion of the Mo-containing layer. After block 457, the deposition cycle is completed in some examples, and the film deposited is a tungsten-containing binary film such as MoB x , MoSi x , and MoGe x , where x is greater than zero. In such embodiments, the process may repeat the cycle of blocks 452 - 457 until the desired thickness is deposited and proceed to block 462. An example of the growth rate can be about 100 Å per cycle.

[0063] In some embodiments, the process proceeds to the operation of optionally introducing a third reactant (block 458). The third reactant generally includes an element introduced into the film such as carbon or nitrogen. Examples of nitrogen-containing reactants are N 2 , NH 3 , and N 2 H 4 . Examples of carbon-containing reactants are CH 4 and C 2 H 2 . An optional purge (block 459) may follow. Then, the process may repeat the deposition cycle and proceed to block 462.

[0064] Examples of three-component films containing nitrogen or carbon have been described above. In some embodiments, the film may contain both nitrogen and carbon (e.g., MoSiCN).

[0065] According to various embodiments, the multi-component tungsten film may have the following atomic percentages: Mo about 5% to 90%, B / Ge / Si about 5% to 60%, C / N about 5% to 80%. In some embodiments, the multi-component film has the following atomic percentages: Mo about 15% to about 80%; B / Ge / Si: about 15% to about 50%; C / N about 20% to about 50%. According to various embodiments, the multi-component Mo film is at least 50% Mo.

[0066] According to various embodiments, the deposition is relatively high, for example, between 500°C and 700°C, such as 550°C to 650°C, and in some embodiments, it is above about 500°C. This promotes the reduction of the Mo-containing precursor and also enables the incorporation of B, Si, or Ge into the two-component film. The upper limit of the range can be limited by thermal budget considerations. In some embodiments, any one or more of blocks 452, 456, and 458 may be executed at a different temperature than any of the other blocks. In certain embodiments, the transition from block 452 to block 456 and the transition from block 456 to block 458 include moving the substrate from one deposition station to another within a multi-station chamber. Further, each of block 452, block 456, and block 458 may be executed at different stations of the same multi-station chamber. In some embodiments, the order of blocks 452, 456, and 458 may be changed.

[0067] In some embodiments, electrical properties such as the work function of a two-component or three-component film may be adjusted by introducing nitrogen or carbon. Similarly, the amount of reducing agent may be adjusted (by modulating the input amount and / or pulse time) to adjust the amount of B, Si, or Ge incorporated into the film. Further, any one or two of the blocks 452, 456, and 458 may be executed more than twice per cycle to adjust the relative amounts of tungsten and other components of the two-component or three-component film, and thus their physical, electrical, and chemical properties. The multi-component layer may include Mo and one or more of B, Si, and Ge, and optionally one or more of C and N. Examples are MoB x , MoSi x , MoGe x , MoB x N y , MoSi x N y , MoGe x N y , MoSi x C y , MoB x C y , MoGe x C y , where x and y are greater than zero.

[0068] In the process described with reference to FIG. 4B, it should be noted that the elements (B, Si, or Ge) in the reducing agent are intentionally incorporated into the Mo-containing film. This is in contrast to the specific PNL and CVD deposition processes described above and the specific embodiments of the deposition process described in FIG. 4B in which B-containing, Si-containing, or Ge-containing reducing agents can be utilized to form an element Mo film having none or trace amounts of these elements. The incorporation of B, Ge, or Si can be controlled by the pulse width and dosage. Further, in some embodiments, a higher temperature may be used to increase the incorporation. If the temperature is too high, it can lead to uncontrolled decomposition of the reaction gas. In some embodiments, as described above with respect to FIG. 4A, the substrate temperature may be low with respect to the reducing agent gas and high with respect to the Mo precursor.

[0069] In some embodiments, the process of FIG. 4B may be modified to execute block 458 such that B, Si, or Ge is not incorporated into the film and C and / or N is incorporated to form, for example, a MoC, MoN, or MoCN film. C and / or N-containing reactants may be used in such embodiments.

[0070] In some embodiments, the multi-component Mo-containing film is a diffusion barrier (e.g., a word line). In some embodiments, the multi-component tungsten-containing film is a work function layer for a metal gate. In some embodiments, a bulk Mo layer may be deposited on the multi-component layer. The bulk layer may, in some embodiments, be deposited directly on the multi-component Mo-containing film without an intermediate layer. In some embodiments, it may be deposited by CVD.

[0071] Experiment WF 6To reduce it, a CVD Mo film was grown on a tungsten nucleation layer deposited by PNL using silane and diborane, respectively. The silane-deposited tungsten nucleation layer is also called the SW nucleation layer, and the diborane-deposited tungsten nucleation layer is also called the BW nucleation layer. The Mo film was deposited from MoOCl 4 and H 2 .

[0072] For each deposition, the process pressures of 30 Torr and 45 Torr were compared. At 30 Torr, no Mo deposition was observed, some W loss was observed, and more W loss was observed in BW nucleation than in SW nucleation. Secondary ion mass spectrometry (SIMS) data showed an O content of less than 1 atomic %.

[0073] Mo was deposited by CVD on SW and BW nucleation layers at different temperatures (500 °C and 520 °C) and different pressures (45 Torr and 60 Torr). Also, the number of times of using the BW or SW cycle for depositing the nucleation layer was changed (1, 2, 3, or 4). Figures 5 and 6 show Mo thickness (angstroms) vs. CVD duration (seconds), and Mo resistivity (μΩ-cm) vs. Mo thickness (angstroms), respectively.

[0074] A lower resistivity was observed at a process pressure of 60 Torr than at 45 Torr. At 60 Torr, no significant difference was observed between 500 °C and 520 °C. At equivalent thicknesses of the BW and SW nucleation layers, a lower resistivity was observed in the SW nucleation layer. A higher resistivity was observed in a thinner (fewer cycle times) SW nucleation layer.

[0075] Mo was deposited on WCN by CVD at different temperatures (500 °C and 520 °C) and different pressures (45 Torr and 60 Torr). Figure 7 shows the Mo growth rate, and Figure 8 shows the resistivity versus Mo film thickness. Figure 9 shows the thickness and resistivity as a function of the thickness of the WCN underlayer. WCN etching was observed at 45 Torr, while uniform Mo deposition was observed at 60 Torr. At 60 Torr, a higher growth rate was observed at 520 °C, and the temperature did not affect the resistivity. Mo was grown on a thin WCN of about 10 angstroms, and the thinner the WCN, the lower the resistivity. SIMS data showed that the total impurities (e.g., O, B, C) in the bulk were less than 0.5 (atomic)%, and the CVD Mo on WCN was smooth.

[0076] In some embodiments, Mo can be selectively deposited on a metal or a pure (without native oxide) Si surface with respect to the dielectric underlayer. For example, for metal contact or middle-of-line (MOL) logic applications, selectively growing Mo on a metal can achieve bottom-up void-free gap filling. In such applications, Mo may be deposited directly on a metal or Si surface adjacent to an exposed silicon dioxide or other exposed dielectric surface. The delay in nucleation on the dielectric is a delay such that Mo is preferentially deposited on the metal surface. For example, a feature having a metal bottom and silicon dioxide sidewalls may be exposed to a Mo-containing precursor and co-reactants. Mo grows bottom-up rather than from the sidewalls.

[0077] Annealing In some embodiments, thermal annealing is performed after Mo deposition. This can enable Mo particle growth and low resistivity. Since the melting point of Mo is lower than that of W, for the Mo film, particle growth and the accompanying decrease in resistivity occur at a lower temperature. Examples of annealing temperatures are in the range of 700 °C to 1100 °C. Annealing may be performed in a furnace or by rapid thermal annealing. According to various embodiments, the annealing is in a hydrogen (H 2 ) atmosphere, nitrogen (N 2)It may be carried out in any suitable atmosphere, such as an atmosphere or a vacuum.

[0078] According to various embodiments, the Mo film may or may not be exposed to air between evaporation and annealing. When the Mo film is exposed to air or other oxidizing environments, molybdenum dioxide (MoO 2 ) or molybdenum trioxide (MoO 3 ) To remove, a reducing environment may be used during or after annealing. In particular, MoO 3 has a melting point of 795 °C and, if not removed, may melt during annealing.

[0079] Table 1 below compares two W films (A and B) and two Mo films (C and D).

Table 1

[0080] Film A is a low-fluorine tungsten (LFW) film deposited using WF 6 . Film B is a tungsten film deposited using WCl 5 and WCl 6 . Film C is a molybdenum film deposited using MoCl 5 , and film D is a molybdenum film deposited using MoOCl 4 . Film D was annealed after deposition. In particular, the resistivity is lower for films C and D than for films A and B. The resistivity decreases with thickness, and 25 μΩ-cm (film C) and 17 μΩ-cm (film D) directly correspond to 40 μΩ-cm (film A). Film D deposited with an O-containing precursor shows low O. The stress of films C and D is comparable to that of films A and B.

[0081] Figure 10 is a graph showing the resistivity decrease after annealing at 800 °C for Mo films of various thicknesses deposited on WCN. The resistivity of the W film on WCN is also shown for comparison. A significant decrease in resistivity is observed. The decrease in resistivity is due to particle growth. Table 2 below shows the phases and average particle sizes of Mo particles in the CVD Mo film immediately after deposition and after annealing. [Table 2] H 2 Furnace annealing at 800 °C for 1 hour and 5 minutes in an atmosphere showed comparable results.

[0082] Apparatus Any suitable chamber can be used to implement the disclosed embodiments. Examples of deposition apparatuses include, for example, ALTUS (registered trademark) and ALTUS (registered trademark) Max manufactured by Lam Research Corporation of Fremont, California, or any of various other commercially available processing systems. The processing can be performed in parallel at multiple deposition stations.

[0083] In some embodiments, the tungsten nucleation process is performed at a first station that is one of 2, 5, or even more deposition stations disposed within a single deposition chamber. In some embodiments, various steps of the nucleation process are performed at two different stations of the deposition chamber. For example, the substrate may be exposed to diborane (B 2 H 6 ) in the first station using an individual gas supply system that forms a local atmosphere on the substrate surface, and then the substrate is transferred to the second station and exposed to a precursor such as tungsten hexachloride (WCl 6 ). In some embodiments, the substrate may then be returned to the first station for a second exposure to diborane or transferred to a third station for a third reactant exposure. Then, WCl 6Transfer the substrate to a second station for exposure to (or other tungsten chlorides) to complete tungsten nucleation and proceed with bulk molybdenum deposition at the same or different stations. Then, using one or more stations, Mo chemical vapor deposition (CVD) can be performed as described above.

[0084] FIG. 11 is a block diagram showing a processing system suitable for performing a deposition process according to an embodiment described herein. System 1100 includes a transfer module 1103. Transfer module 1103 provides a clean pressurized environment to minimize the risk of contamination when the substrate being processed is moved between various reactor modules. Mounted on transfer module 1103 is a multi-station reactor 1109 capable of performing nucleation layer deposition (also referred to as pulsed nucleation layer (PNL) deposition) and CVD deposition according to an embodiment described herein. Chamber 1109 may include a plurality of stations 1111, 1113, 1115, and 1117 that can perform these operations in sequence. For example, chamber 1109 may be configured such that stations 1111 and 1113 perform PNL deposition and stations 1113 and 1115 perform CVD. Each deposition station may include a heated wafer pedestal and a showerhead, diffusion plate, or other gas inlet.

[0085] Also, one or more single-station modules or multi-station modules 1107 capable of performing plasma pre-cleaning or chemical (non-plasma) pre-cleaning may be mounted on the transfer module 1103. The modules may be used for various other processes (e.g., reducing agent immersion). The system 1100 also includes one or more (two in this example) wafer source modules 1101 in which wafers are housed before and after processing. An atmospheric robot (not shown) in the atmospheric transfer chamber 1119 first removes the wafers from the source module 1101 to the load lock 1121. A wafer transfer device (generally a robot arm unit) in the transfer module 1103 moves the wafers from the load lock 1121 to the modules mounted on the transfer module 1103 and between the modules.

[0086] In certain embodiments, a system controller 1129 is used to control the processing conditions during deposition. The controller typically includes one or more memory devices and one or more processors. The processor may include a CPU or computer, analog and / or digital input / output connections, a stepper motor controller board, etc.

[0087] The controller may control all operations of the deposition apparatus. The system controller executes system control software including a series of instructions for controlling timing, gas mixing, chamber pressure, chamber temperature, wafer temperature, radio frequency (RF) power level if used, the position of the wafer chuck or pedestal, and other parameters of a particular process. Other computer programs stored in the memory device associated with the controller may be used in some embodiments.

[0088] Typically, there is a user interface associated with the controller. The user interface may include a display screen (a graphical software display of the apparatus and / or processing conditions) and user input devices such as a pointing device, keyboard, touch screen, microphone, etc.

[0089] The system control logic may be configured in any suitable way. Generally, the logic can be designed or configured in hardware and / or software. Instructions for controlling the drive circuit may be hard-coded or provided as software. The instructions can be provided by "programming". Such programming is understood to include any form of logic, such as logic hard-coded in a digital signal processor, an application-specific integrated circuit, and other devices having specific algorithms implemented in hardware. Also, the programming is understood to include software instructions or firmware instructions that can be executed on a general-purpose processor. The system control software may be coded in any suitable computer-readable programming language. Alternatively, the control logic may be hard-coded in a controller. For these purposes, application-specific integrated circuits, programmable logic devices (e.g., field-programmable gate arrays or FPGAs), etc. may be used. In the following, when "software" or "code" is utilized, functionally equivalent hard-coded logic may be utilized instead.

[0090] The computer program code for controlling the deposition process and other processes within the process procedure can be written in any conventional computer-readable programming language, such as assembly language, C, C++, Pascal, Fortran, etc. The compiled object code or script is executed by the processor to perform the tasks specified within the program.

[0091] The control parameters are related to process conditions such as the composition and flow rate of the process gas, temperature, pressure, plasma conditions (such as RF power level and low-frequency RF frequency), cooling gas pressure, and the temperature of the chamber walls. These parameters are provided to the user in the form of a recipe and can be input using the user interface.

[0092] Signals for monitoring the process may be provided by the analog and / or digital input connections of the system controller. Signals for controlling the process are output at the analog and digital output connections of the deposition apparatus.

[0093] The system software can be designed or configured in many different ways. For example, various chamber component subroutines or control objects may be written to control the operation of the chamber components necessary to perform the deposition process of the present invention. Examples of programs or program sections for this include substrate placement code, process gas control code, pressure control code, heater control code, and plasma control code.

[0094] In some embodiments, the controller 1129 is part of a system, and the system may be part of the examples described above. Such a system may include a semiconductor processing apparatus, such as one or more processing tools, one or more chambers, one or more platforms for processing, and / or specific processing components (such as wafer pedestals, gas flow systems, etc.). These systems may be integrated with electronics for controlling the operation of the system before, during, and after the processing of semiconductor wafers or substrates. The electronics may be referred to as a "controller" and may control various components or sub-components of the system. Depending on the processing requirements and / or the type of system, the controller 1129 may be programmed to control any of the processes disclosed herein, such as the supply of process gas, temperature setting (e.g., heating and / or cooling), pressure setting, vacuum setting, power setting, radio frequency (RF) generator setting in some systems, RF matching circuit setting, frequency setting, flow rate setting, fluid supply setting, position and motion setting, and wafer transfer into and out of the load lock connected or coupled to the tool and other moving tools and / or a specific system.

[0095] Generally, a controller may be defined as an electronic device having various integrated circuits, logic, memory, and / or software that receive instructions, issue instructions, control operations, enable cleaning operations, enable endpoint measurements, etc. The integrated circuits may 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 execute program instructions (e.g., software). The program instructions may be communicated to the controller in the form of various individual settings (or program files) that define operating parameters for performing a specific process on or for a semiconductor wafer, or operating parameters for the system. The operating parameters may, in some embodiments, be part of a recipe defined by a process engineer to achieve one or more processing steps during the processing of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or dies of the wafer.

[0096] In some embodiments, the controller 1129 may be integrated with the system, connected to the system, networked with the system in some other way, or be part of a computer coupled to the system in a combination thereof, and may also be connected to such a computer. For example, the controller 1129 may be within the "cloud", or may be all or part of a fab host computer system that enables remote access to wafer processing. The computer may enable remote access to the system to monitor the current progress of the manufacturing operation, examine the history of past manufacturing operations, or examine trends or performance metrics from multiple manufacturing operations, to change the parameters of the current process, set up the processing steps according to the current process, or initiate a new process. In some examples, a remote computer (e.g., a server) may provide a processing 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 enables input or programming of parameters and / or settings, and the parameters and / or settings are communicated from the remote computer to the system. In some examples, the controller receives instructions in the form of data, and the instructions specify parameters for each of the processing steps to be executed during one or more operations. It should be understood that the parameters may be specific to the type of process being executed and the type of tool that the controller is configured to interface with or control. Thus, as described above, the controller may be distributed, such as by comprising one or more separate controllers networked together to operate towards a common purpose (such as the processes and controls described herein). An example of a distributed controller for such a purpose is one or more integrated circuits on a chamber that communicate with one or more remotely located (such as at the platform level or as part of a remote computer) integrated circuits that cooperate to control the processing in the chamber.

[0097] Although not limited, examples of the system can include a plasma etching chamber or module, a deposition chamber or module, a spin rinse chamber or module, a metal plating chamber or module, a cleaning chamber or module, a bevel edge etching chamber or module, a physical vapor deposition (PVD) chamber or module, a CVD chamber or module, an ALD chamber or module, an atomic layer etching (ALE) chamber or module, an ion implantation chamber or module, a track chamber or module, and any other semiconductor processing system that may be related to or utilized in the processing and / or manufacturing of semiconductor wafers.

[0098] As described above, depending on one or more processing steps performed by the tool, the controller may communicate with one or more of other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, nearby tools, tools located throughout the factory, a main computer, another controller, or a tool used for transporting the wafer container to or from a tool location and / or load port within the semiconductor manufacturing factory.

[0099] The controller 1129 may comprise various programs. The substrate placement program may comprise program code for loading a substrate onto a pedestal or chuck and for controlling chamber components used to control the spacing between the substrate and other parts of the chamber (such as gas inlets and / or gas targets). The process gas control program may comprise code for controlling the gas composition and flow rate and optionally for flowing gas into the chamber prior to deposition to stabilize the pressure within the chamber. The pressure control program may comprise code for controlling the pressure within the chamber, for example, by adjusting a throttle valve in the chamber's exhaust system. The heater control program may comprise code for controlling the current to a heating unit used to heat the substrate. Alternatively, the heater control program may control the supply of a heat transfer gas (such as helium) to the wafer chuck.

[0100] Examples of chamber sensors that may be monitored during deposition include mass flow controllers, pressure sensors (such as manometers), and thermocouples disposed within the pedestal or chuck. Appropriately programmed feedback algorithms and control algorithms may be used with data from these sensors to maintain desired process conditions.

[0101] The implementation of embodiments of the present disclosure in a single-chamber or multi-chamber semiconductor processing tool has been described above.

[0102] The above has described the implementation of the disclosed embodiments in a single-chamber or multi-chamber semiconductor processing tool. The devices and processes described herein may be used in conjunction with lithography patterning tools or processes, for example, for the processing or manufacturing of semiconductor devices, displays, LEDs, photovoltaic panels, etc. Typically, but not necessarily, such tools / processes are utilized or executed together in a common manufacturing facility. Lithographic patterning of thin films typically includes some or all of the following steps, each step being provided by a plurality of possible tools: (1) applying a photoresist onto a workpiece (i.e., a substrate) using a spin-on or spray-on tool; (2) curing the photoresist using a hot plate or furnace or UV curing tool; (3) exposing the photoresist to visible light or UV or X-rays using a tool such as a wafer stepper; (4) developing the resist to pattern it by selectively removing the resist using a tool such as a wet bench; (5) transferring the resist pattern to the underlying film or workpiece using a dry etching tool or a plasma-assisted etching tool; and (6) removing the resist using a tool such as an RF plasma or microwave plasma resist stripper.

[0103] Conclusion For better understanding, the present embodiment has been described in some detail, but it is clear that some changes and modifications may be made within the scope of the appended claims. Note that there are many other ways to implement the processes, systems, and devices of the present invention. Therefore, the present embodiment is considered to be illustrative and not limiting, and the embodiments are not limited to the details shown herein.

Claims

1. 1. A method comprising: providing a tungsten (W)-containing layer on a substrate; depositing a molybdenum (Mo)-containing layer onto the W-containing layer; A method comprising:

2. The method of claim 1 , wherein the W-containing layer is a WCN layer.

3. The method of claim 1 , wherein the W-containing layer is a W nucleation layer.

4. 4. The method of claim 1, wherein the W-containing layer is deposited from one or more tungsten chloride precursors.

5. 4. The method of claim 1, wherein the Mo-containing layer is a Mo layer having less than 1 (atomic) % impurities.

6. 4. The method of claim 1, further comprising the step of thermally annealing the Mo-containing layer.

7. 4. The method according to claim 1, wherein the Mo-containing layer is formed by a process comprising the steps of: ６ ), molybdenum pentachloride (MoCl ５ ), molybdenum dioxide dichloride (MoO ２ C ２ ), molybdenum oxide tetrachloride (MoOCl ４ ), and molybdenum hexacarbonyl (Mo(CO) ６ and a Mo-containing precursor selected from the group consisting of W-containing layer,

8. 8. The method of claim 7, wherein the substrate temperature during exposure to the Mo-containing precursor is less than 550°C.

9. 8. The method of claim 7, wherein the substrate is exposed to the reducing agent at a first substrate temperature and to the Mo-containing precursor at a second substrate temperature, the first substrate temperature being lower than the second substrate temperature.

10. 10. The method of claim 9, wherein the reducing agent is a mixture of a boron-containing reducing agent and a silicon-containing reducing agent.

11. 1. A method comprising: flowing a reducing agent gas into a process chamber containing the substrate at a first substrate temperature to form a conformal reducing agent layer on the substrate; exposing the conformal reducing agent layer to a molybdenum-containing precursor at a second substrate temperature to convert the reducing agent layer to molybdenum; A method comprising:

12. 12. The method of claim 11, wherein the first substrate temperature is lower than the second substrate temperature.

13. 13. The method of claim 11 or 12, wherein the reducing agent is a mixture of a boron-containing reducing agent and a silicon-containing reducing agent.

14. 13. The method of claim 11 or 12, wherein the first substrate temperature is less than or equal to 400°C and the second substrate temperature is greater than or equal to 500°C.

15. 13. The method of claim 11 or 12, further comprising the step of annealing the molybdenum.

16. 1. A method comprising: pulsing a reducing agent, the reducing agent being boron (B)-containing, silicon (Si)-containing, or germanium (Ge)-containing; pulsing a Mo-containing precursor, the Mo-containing precursor is reduced by the reducing agent or a product of the reducing agent to form a multi-component tungsten-containing film containing one or more of B, Si, and Ge on the substrate; A method comprising:

17. 17. The method of claim 16, wherein the multi-component tungsten-containing film comprises 5% to 60% (atomic %) of B, Si, or Ge, and the 5% to 60% (atomic %) of B, Si, or Ge is provided by the reducing agent.

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