Deposition of molybdenum-containing films

Abstract

To provide a vapor-depositing method for forming a thin film including molybdenum on a base material.SOLUTION: A method includes a plurality of deposition cycles of separately contacting a base material to a vapor-phase molybdenum precursor including molybdenum halide, a first reactant including CO and a second reactant including H2. A thin film includes MoC, Mo2C or MoOC, and the thin film including molybdenum, carbon and nitrogen, such as MoCN or MoOCN is deposited by additionally contacting the base material to a nitrogen reactant.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] This application relates generally to vapor deposition methods for forming films comprising molybdenum. Thin films comprising molybdenum carbon can be deposited by cyclic vapor deposition methods such as atomic layer deposition using, for example, CO and H as reducing agents. [Background technology]

[0002] Titanium nitride (TiN) is one of the most widely used materials in the semiconductor industry and is therefore deposited for many purposes, such as liners and barrier / adhesion layers. However, TiN films have relatively high resistivity and cannot be scaled up to the higher p-metal work function requirements for advanced IC nodes. Molybdenum carbide films can provide an alternative to TiN films. However, deposition methods for forming molybdenum films using halide reactants typically suffer from the disadvantages of etching or contaminating other materials. Summary of the Invention

[0003] In one aspect, a vapor deposition method is provided for depositing a thin film comprising molybdenum. In some embodiments, the thin film comprises molybdenum and carbon, such as a molybdenum carbide (MoC, MoC) thin film, a molybdenum oxycarbide (MoOC) thin film, a molybdenum oxycarbide nitride (MoOCN) thin film, or a molybdenum carbonitride (MoCN) thin film, is provided by the vapor deposition method. In some embodiments, the deposition method is an atomic layer deposition (ALD) process.

[0004] In some embodiments, a deposition method for forming a thin film containing molybdenum, such as a thin film containing molybdenum and carbon, on a substrate in a reaction space includes multiple deposition cycles, including contacting the substrate with a first reactant containing a gas-phase molybdenum precursor, such as a molybdenum halide, and then contacting the substrate with a gas-phase second reactant containing carbon and oxygen, such as CO, and a gas-phase third reactant containing hydrogen, such as H. The deposition cycle may be repeated two or more times to form a thin film containing molybdenum. In some embodiments, the thin film comprises molybdenum and carbon. In some embodiments, the substrate is contacted alternately and sequentially with the first reactant, the second reactant, and the third reactant. In some embodiments, the substrate is contacted with the first reactant, and then with the second reactant and the third reactant simultaneously.

[0005] In some embodiments, the thin film is a MoC, MoC, or MoOC thin film. In some embodiments, the thin film is a MoOCN or MoCN thin film. In some embodiments, the thin film is a molybdenum thin film.

[0006] In some embodiments, the molybdenum precursor is a molybdenum halide such as MoCl, MoBr, or MoI. In some embodiments, the molybdenum precursor is a molybdenum oxyhalide such as MoOCl, or MoOCl.

[0007] In some embodiments, the only reactants used in a deposition cycle are the molybdenum precursor, the second reactant, and the third reactant, hi some embodiments, the only reactants used in a deposition cycle are the molybdenum precursor, CO, and H2.

[0008] In some embodiments, the deposition method further comprises contacting the substrate with one or more additional reactants. In some embodiments, the fourth reactant comprises nitrogen, e.g., a fourth reactant comprising NH. In some embodiments, the fourth reactant comprises oxygen. In some embodiments, the substrate is contacted with an oxygen reactant, such as HO, O, HO, NO, NO, or NO. In some embodiments, the substrate is contacted with a fourth reactant after contacting the substrate with the first reactant and before contacting the second reactant and the third reactant. In some embodiments, the substrate is contacted with the fourth reactant after contacting the first, second, and third reactants.

[0009] In some embodiments, the deposition cycle includes sequentially contacting the substrate with a first reactant including a molybdenum precursor, contacting the substrate with a second reactant such as CO, and contacting the substrate with a third reactant such as H. In some embodiments, the deposition cycle includes sequentially contacting the substrate with the first precursor, and then simultaneously contacting the substrate with a second reactant and a third reactant. In some embodiments, the third reactant further includes NH. In some embodiments, the substrate is separately contacted with a fourth reactant including NH.

[0010] In some embodiments, the cobalt thin film is deposited on the molybdenum-containing thin film.

[0011] In some embodiments, a deposition cycle for depositing molybdenum carbide or molybdenum oxycarbide includes, in sequence, contacting the substrate with a first reactant comprising a molybdenum precursor, contacting the substrate with a second reactant comprising CO, and contacting the substrate with a third reactant comprising H. In some embodiments, a deposition cycle includes, in sequence, contacting the substrate with the first precursor, and then simultaneously contacting the substrate with the second reactant and the third reactant.

[0012] In some embodiments, a method for forming a thin film comprising molybdenum, carbon, and nitrogen on a substrate in a reaction space comprises a deposition cycle comprising contacting the substrate with a first reactant comprising a molybdenum precursor, such as a molybdenum halide, and then contacting the substrate with a second reactant comprising CO, and a third reactant comprising NH.

[0013] The deposition cycle may be repeated two or more times to form a thin film of the desired thickness. In some embodiments, excess reactants and reaction by-products, if any, are removed from the reaction space after each contacting step, e.g., after contacting the substrate with a first reactant and before contacting the substrate with a second reactant and / or a third reactant.

[0014] In some embodiments, the only reactants used in a deposition cycle are molybdenum halide, CO, and H. In some embodiments, the only reactants used in a deposition cycle are molybdenum halide, CO, and NH. In some embodiments, a third reactant comprises NH and H. In some embodiments, the only reactants used in a deposition cycle are molybdenum halide, CO, H, and NH.

[0015] The embodiments described herein will be better understood from the detailed description and from the accompanying drawings which are intended to illustrate, but not to limit, the invention. [Brief explanation of the drawings]

[0016] [Figure 1] 1A and 1B are simplified cross-sectional views of a semiconductor device structure and a gap-fill structure according to certain embodiments. [Figure 2] 1 is a flowchart illustrating a method for depositing a metal film comprising molybdenum and carbon by atomic layer deposition (ALD) deposition, according to certain embodiments. [Figure 3]1 is a flowchart illustrating a method for depositing a metal film comprising molybdenum and carbon by atomic layer deposition (ALD) deposition, according to certain embodiments. [Figure 4] 1 is a flowchart illustrating a method for depositing a metal film comprising molybdenum and carbon by atomic layer deposition (ALD) deposition, according to certain embodiments. DETAILED DESCRIPTION OF THE INVENTION

[0017] Vapor deposition methods can be used to deposit molybdenum-containing materials, such as thin films containing molybdenum, thin films containing molybdenum and carbon, and thin films containing molybdenum, carbon, and nitrogen. In some embodiments, vapor deposition methods utilize a first reactant comprising a molybdenum precursor such as a molybdenum halide, a second vapor-phase reactant, and a third vapor-phase reactant. In some embodiments, one or both of the second and third reactants may comprise a reducing agent. In some embodiments, both the second and third reactants comprise a reducing agent. In some embodiments, the second reactant comprises a carbon source, e.g., CO. In some embodiments, the third reactant comprises H and / or NH. In some embodiments, the third vapor-phase reactant may comprise hydrazine. In some embodiments, additional reactants may also be utilized, e.g., H and / or NH. In some embodiments, additional reactants comprising oxygen, such as HO, O, HO, NO, NO, or NO, may be utilized. In some embodiments, a thin film containing molybdenum, such as a molybdenum film, a thin film containing molybdenum and carbon, such as a molybdenum carbide (e.g., MoC, MoC) thin film, a molybdenum oxycarbide (MoOC) thin film, or a thin film containing molybdenum, carbon, and nitrogen, such as a molybdenum oxycarbonitride (MoOCN) thin film or a molybdenum carbonitride (MoCN) thin film, is deposited by a vapor deposition method. In some embodiments, the vapor deposition method is an atomic layer deposition (ALD) process.

[0018] In some embodiments, thin films comprising molybdenum or comprising molybdenum and carbon, such as molybdenum carbide, molybdenum oxycarbide, molybdenum carbonitride, or molybdenum oxycarbonitride, deposited by the methods of the present disclosure can be used in any of a variety of contexts, such as gate materials in CMOS structures or as barrier / adhesion layers for gap-fill structures, as shown, for example, in FIGS. 1A and 1B . In some embodiments, the thin films can be used as adhesion layers in cobalt gap-fill processes. In some embodiments, the thin films can be used as low-resistivity P metal for metal gates. In some embodiments, the thin films can be used as low-resistivity barrier or nucleation layers for metallization in logic or memory applications.

[0019] As a non-limiting example, FIG. 1A is a simplified cross-sectional view of a semiconductor device structure 100 according to certain embodiments, and FIG. 1B is a simplified cross-sectional view of a gap-fill structure 120 according to certain embodiments. Referring to FIG. 1A, the semiconductor device structure 100 includes a substrate 102 and a gate structure 103 on the substrate 102. The gate structure 103 includes a gate dielectric layer 104 on the substrate, a gate metal layer 106 including molybdenum and carbon, such as MoC, MoC, MoOC, MoOCN, or MoCN, on the gate dielectric layer 104, and a conductive layer 108 on the gate metal layer 106. Spacers 110 may be formed on sidewalls of the gate dielectric layer 104, the gate metal layer 106, and the conductive layer 108. In some embodiments, the gate metal layer 106 may include molybdenum and carbon and may be formed by a vapor deposition method described herein, such as by an atomic layer deposition process. In some embodiments, the gate metal layer 106 may include molybdenum oxycarbide.

[0020] Referring to FIG. 1B , gap-fill structure 120 includes substrate 122, dielectric layer 124, barrier / adhesion layer 126 including molybdenum and carbon, such as MoC, MoC, MoOC, MoOCN, or MoCN, and gap-fill layer 128. Dielectric layer 124 is patterned, and barrier / adhesion layer 126 is conformally formed on the patterned dielectric layer, for example, on the bottom and sidewalls of the recess. Gap-fill layer 128 fills the recess. In some embodiments, barrier / adhesion layer 126 may be formed by a vapor deposition method described herein, such as by an atomic layer deposition process. In some embodiments, gap-fill layer 128 includes cobalt. In some embodiments, barrier / adhesion layer 126 may include molybdenum oxycarbide.

[0021] A gate metal layer 106 comprising molybdenum and carbon, such as MoC, Mo2C, MoOC, MoOCN, or MoCN, and a barrier / adhesion layer 126 comprising molybdenum and carbon, such as MoC, Mo2C, MoOC, MoOCN, or MoCN, can provide lower resistivity compared to TiN, which is commonly used in these situations. Other situations in which the disclosed molybdenum and carbon-containing thin films can be utilized will be apparent to those skilled in the art.

[0022] Atomic Layer Deposition (ALD) As described above, vapor deposition methods are provided for depositing molybdenum-containing or molybdenum and carbon-containing materials, such as Mo, MoC, MoC, MoOC, MoOCN, or MoCN thin films. In some embodiments, the vapor deposition method is an atomic layer deposition process in which a surface of a substrate is alternately and sequentially contacted with two or more reactants.

[0023] In some embodiments, a molybdenum-containing material is deposited on a substrate in a reaction space by contacting the surface of the substrate with three reactants: a first reactant comprising a molybdenum precursor, a second reactant, and a third reactant. In some embodiments, the second reactant comprises carbon, such as CO. In some embodiments, the third reactant comprises H2 and / or NH3. In some embodiments, the second reactant comprises a first reducing agent and the third reactant comprises a second reducing agent. In some embodiments, the first reducing agent is different from the second reducing agent. In some embodiments, the first reducing agent and the second reducing agent are the same. In some embodiments, the first reducing agent may comprise carbon. In some embodiments, the second reducing agent comprises hydrogen. In some embodiments, the first reactant comprises a molybdenum precursor, the second reactant comprises CO, and the third reactant comprises H2. In some embodiments, the deposition method includes a deposition cycle in which a substrate in a reaction chamber is alternately and sequentially contacted with a first reactant comprising a vapor-phase molybdenum precursor, a second reactant comprising a first reducing agent, and a third reactant comprising a second reducing agent. In some embodiments, the substrate in the reaction chamber is alternately and sequentially contacted with a first reactant comprising a vapor-phase molybdenum precursor, a second reactant comprising CO, and a third reactant comprising H. In some embodiments, the substrate is simultaneously contacted with the second reactant and the third reactant. The deposition cycle may be repeated two or more times to deposit a thin film of a desired thickness.

[0024] Although referred to as a first reactant, a second reactant, and a third reactant, they are not necessarily contacted with the substrate in that order during a deposition cycle. In some embodiments, the reactants are contacted with the substrate in the following order: first reactant, second reactant, and third reactant. In some embodiments, the substrate is contacted with one or both of the second reactant and the third reactant before the first reactant. In some embodiments, the substrate is contacted sequentially with a first reactant comprising a molybdenum precursor, followed by a second reactant and a third reactant.

[0025] In some embodiments, the substrate is first contacted with a first reactant comprising a molybdenum precursor, and then simultaneously contacted with a second reactant and a third reactant, e.g., CO and H. In some embodiments, the first reactant comprising a molybdenum precursor, the second reactant, and the third reactant are the only reactants utilized in a deposition cycle. In some embodiments, the molybdenum precursor, CO, and H are the only reactants utilized in a deposition cycle. In some embodiments, a thin film deposited using a molybdenum precursor, CO, and H comprises Mo, MoC, MoC, or MoOC. In some embodiments, the ratio of CO and H can be adjusted to deposit MoOC. Adjustment can be achieved, for example, by adjusting the exposure time of the substrate to each reactant or by adjusting the ratio of reactants provided throughout the deposition process.

[0026] In some embodiments, a material comprising molybdenum, carbon, and nitrogen is deposited on a substrate in a reaction space by contacting the surface of the substrate with a first reactant comprising a molybdenum precursor, a second reactant comprising a first reducing agent, and a third reactant comprising a nitrogen reactant, such as NH3. In some embodiments, the deposition method includes a deposition cycle in which the substrate is alternately and sequentially contacted with a first reactant comprising a gas-phase molybdenum precursor, a second reactant comprising carbon, such as CO, and a third reactant comprising nitrogen, such as NH3. In some embodiments, the substrate may be contacted with the second and third reactants simultaneously. The deposition cycle may be repeated two or more times to deposit a thin film of a desired thickness.

[0027] Although referred to as a first reactant, a second reactant, and a third reactant, they are not necessarily contacted with the substrate in that order during a deposition cycle. In some embodiments, the reactants are contacted with the substrate in the following order: first reactant, second reactant, and third reactant. In some embodiments, the substrate is contacted with one or both of the second reactant and the third reactant before the first reactant. In some embodiments, the substrate is contacted sequentially with a first reactant comprising a molybdenum precursor, followed by a second reactant and a third reactant.

[0028] In some embodiments, the deposition method includes a deposition cycle in which the substrate is alternately and sequentially contacted with a first reactant comprising a gas-phase molybdenum precursor, CO, and NH3. In some embodiments, the substrate is contacted simultaneously with CO and NH3. In some embodiments, the substrate is contacted sequentially with a first reactant comprising a molybdenum precursor, then a second reactant and a third reactant. In some embodiments, the substrate is first contacted with a first reactant comprising a molybdenum precursor, and then with a second reactant and a third reactant, e.g., CO and NH3, simultaneously. In some embodiments, the molybdenum precursor, CO, and NH3, are the only reactants utilized in the deposition cycle. In some embodiments, the thin film comprises MoCN or MoOCN. In some embodiments, the ratio of CO to NH3 can be adjusted to deposit MoOCN.

[0029] In some embodiments, a molybdenum-, carbon-, and nitrogen-containing material is deposited on a substrate in a reaction space by contacting the surface of the substrate with a first reactant comprising a molybdenum precursor, a second reactant comprising a first reducing agent, a third reactant comprising a second reducing agent such as H, and a fourth reactant comprising a nitrogen reactant such as NH. In some embodiments, the deposition method includes a deposition cycle in which the substrate is alternately and sequentially contacted with a first reactant comprising a gas-phase molybdenum precursor, a second reactant comprising carbon such as CO, a third reactant comprising H, and a fourth reactant comprising nitrogen such as NH. In some embodiments, the substrate is contacted simultaneously with at least two of the second reactant, the third reactant, and the fourth reactant. In some embodiments, the substrate is contacted simultaneously with the second reactant and the third reactant. In some embodiments, the substrate is contacted simultaneously with the third reactant and the fourth reactant. In some embodiments, the substrate is contacted simultaneously with the second reactant and the fourth reactant. In some embodiments, the substrate is contacted with the second reactant, the third reactant, and the fourth reactant simultaneously. The deposition cycle may be repeated two or more times to deposit a thin film of a desired thickness.

[0030] Although referred to as a first reactant, a second reactant, a third reactant, and a fourth reactant, they are not necessarily contacted with the substrate in that order during a deposition cycle. In some embodiments, the reactants are contacted with the substrate in the following order: first reactant, second reactant, third reactant, and fourth reactant. In some embodiments, the substrate is contacted with one or more of the second reactant, third reactant, and / or fourth reactant before the first reactant. In some embodiments, the substrate is contacted sequentially with a first reactant comprising a molybdenum precursor, followed by the first reactant, second reactant, and third reactant.

[0031] In some embodiments, the substrate is contacted alternately and sequentially with a first reactant comprising a gas phase molybdenum precursor, CO, H2, and NH3. In some embodiments, the substrate is contacted simultaneously with CO, H2, and / or NH3. In some embodiments, the substrate is contacted alternately and sequentially with a first reactant comprising a gas phase molybdenum precursor, CO, H2, and NH3. In some embodiments, the substrate is contacted with a first reactant comprising a molybdenum precursor, then separately with one of CO, H2, and NH3, and then simultaneously with two or more other reactants of CO, H2, and NH3.

[0032] In some embodiments, the substrate is sequentially contacted with a first reactant containing a molybdenum precursor, a second reactant, and then simultaneously contacted with a third reactant and a fourth reactant. For example, the substrate may be sequentially contacted with a first reactant containing a molybdenum precursor and CO, and then simultaneously contacted with H and NH. In some embodiments, the substrate is first contacted with a first reactant containing a molybdenum precursor, and then simultaneously contacted with a second reactant, a third reactant, and a fourth reactant, e.g., CO, H, and NH. In some embodiments, the first reactant containing a molybdenum precursor, the second reactant containing a carbon such as CO, the third reactant containing a reducing agent such as H, and the fourth reactant containing a nitrogen reactant such as NH are the only reactants used in a deposition cycle. In some embodiments, the molybdenum precursor, CO, H, and NH are the only reactants utilized in a deposition cycle. In some embodiments, the thin film comprises MoOCN or MoCN. In some embodiments, the ratio of the second reactant to the third reactant and the fourth reactant is adjusted to preferentially deposit MoCN or MoOCN.

[0033] In some embodiments, the molybdenum precursor comprises a molybdenum halide. In some embodiments, the molybdenum precursor comprises a molybdenum oxyhalide. For example, in some embodiments, the molybdenum precursor may comprise at least one of MoO2Cl2, MoCl5, MoOCl4, MoBr2, or MoI3. In some embodiments, the molybdenum precursor may consist of at least one of MoO2Cl2, MoCl5, MoOCl4, MoBr2, or MoI3.

[0034] In some embodiments, molybdenum oxyhalides are used in deposition methods to deposit Mo, MoOC, or MoOCN. For example, in some embodiments, Mo films are deposited by a deposition cycle in which a substrate is contacted with a first reactant comprising a molybdenum precursor including MoOCl or MoOCl, a second reactant comprising carbon such as CO, and a third reactant comprising a reducing agent such as H. In some embodiments, the second reactant comprises a reducing agent, and the reducing agents in the first and second reactants are different. In some embodiments, the reducing agents may be the same.

[0035] In some embodiments, the deposition method is an atomic layer deposition (ALD) process. In some embodiments, a conformal thin film comprising molybdenum and carbon is deposited, for example, on a three-dimensional structure on a substrate. Among vapor deposition techniques, ALD has the advantage of typically providing high conformality at low temperatures.

[0036] ALD-type processes are based on controlled surface reactions of precursor chemicals. In some embodiments, the surface reactions are generally self-limiting. Gas-phase reactions are typically avoided by alternately and sequentially feeding precursors into the reaction chamber. Gas-phase reactants are separated from one another within the reaction chamber, for example, by removing excess reactants and / or reaction by-products from the reaction chamber between reactant pulses.

[0037] As mentioned above, before film deposition begins, the substrate is typically heated to an appropriate growth temperature. Briefly, the substrate is heated to an appropriate deposition temperature, generally under reduced pressure. The preferred deposition temperature can vary depending on many factors, including, but not limited to, the composition of the substrate, including reactant precursors, pressure, flow rates, reactor configuration, and the nature of the material being deposited. The deposition temperature is generally maintained below the thermal decomposition temperature of the reactants, but at a level high enough to avoid reactant condensation and provide activation energy for the desired surface reactions. Of course, the appropriate temperature window for any given ALD reaction will depend on the surface termination and the reactant species involved. Here, the temperature varies depending on the precursors used and is generally about 700°C or less; in some embodiments, the deposition temperature is generally about 100°C or more and about 700°C or less; in some embodiments, the deposition temperature is about 200°C to about 700°C; and in some embodiments, the deposition temperature is about 300°C to about 500°C. In some embodiments, the deposition temperature is less than about 500° C., less than about 400° C., or less than about 300° C. In some examples, the deposition temperature may be greater than about 200° C., greater than about 150° C., or greater than about 100° C. In some embodiments, lower deposition temperatures may be achieved, for example, when additional reactants or reducing agents are used in the process, such as hydrogen-containing reactants or reducing agents.

[0038] In a deposition cycle, the surface of the substrate is contacted with a first reactant comprising a gas-phase molybdenum precursor, also referred to as a molybdenum precursor. In some embodiments, a pulse of the gas-phase molybdenum precursor is delivered to a reaction space containing the substrate (e.g., in time-resolved ALD). In some embodiments, the substrate is moved into a reaction space containing the gas-phase molybdenum precursor (e.g., in space-resolved ALD, also known as spatial ALD). Conditions can be selected such that no more than about a monolayer of the molybdenum precursor or species thereof is adsorbed onto the first surface of the substrate. Conditions can be selected such that the precursor adsorbs in a self-limiting manner. An appropriate contact time can be readily determined by one of ordinary skill in the art based on the particular circumstances. Excess first reactant and reaction by-products, if any, are removed from the surface of the substrate by purging with an inert gas or by moving the substrate away from the presence of the first reactant.

[0039] The molybdenum precursor and additional reactants are typically maintained separately and contact the substrate separately. In particular, the molybdenum precursor is typically provided separately from the other reactants. However, as discussed herein, in some embodiments, two or more additional reactants may be provided together. Furthermore, some configurations, such as hybrid CVD / ALD processes or cyclic CVD processes, allow for the superposition of different mutually reactive reactants on the substrate, thus producing more than a monolayer per cycle. The vapor-phase precursor and / or vapor-phase byproducts are removed from the substrate surface, for example, by evacuating the chamber with a vacuum pump and / or by purging (e.g., by replacing the gas in the reactor with an inert gas, such as argon or nitrogen). The supply of precursor or reactant to the substrate surface is typically stopped during the removal period and may be shunted to a different chamber or vacuum pump during the removal period. Typical removal times are about 0.05 to 20 seconds, about 1 to 10 seconds, or about 1 to 2 seconds. However, other removal times may be utilized as needed, for example, when a high degree of conformal step coverage is required on very high aspect ratio structures or other structures with complex surface morphology.

[0040] The surface of the substrate is contacted with a second reactant in a vapor phase. In some embodiments, the second reactant comprises a first reducing agent, and in some embodiments, the second reactant comprises carbon. In some embodiments, the second reactant comprises CO. In some embodiments, the second reactant comprises CO and H. In some embodiments, the second reactant comprises CO, H, and NH. In some embodiments, pulses of the second reactant are provided to a reaction space containing the substrate. In some embodiments, the substrate is moved to a reaction space containing the second reactant in a vapor phase. Excess second reactant and gaseous by-products of the surface reaction, if any, are removed from the surface of the substrate. In some embodiments, a deposition cycle comprises alternately and sequentially contacting the substrate with a molybdenum precursor and a second reactant. In some embodiments, one or more additional reactants are utilized.

[0041] In some embodiments, after removal of the second reactant and gaseous by-products, in some embodiments, the surface of the substrate is contacted with a third vapor-phase reactant or precursor. In some embodiments, the third vapor-phase reactant comprises a second reducing agent. In some embodiments, the second reducing agent is different from the first reducing agent. In some embodiments, the second reducing agent is the same as the first reducing agent. In some embodiments, the third vapor-phase reactant comprises hydrogen. In some embodiments, the third vapor-phase reactant comprises H. In some embodiments, the third vapor-phase reactant comprises NH. In some embodiments, the third vapor-phase reactant comprises both NH and H. In some embodiments, a pulse of the third reactant is provided to the reaction space containing the substrate. In some embodiments, the substrate is moved to a reaction space containing the vapor-phase third reactant. Excess third reactant and gaseous by-products of the surface reaction, if any, are removed from the surface of the substrate.

[0042] In some embodiments, the second reactant and the third reactant may be provided simultaneously or in overlapping pulses, for example, in some embodiments, a second reactant comprising CO and a third reactant comprising H are provided simultaneously or in overlapping pulses.

[0043] In some embodiments, the substrate may be contacted with a fourth gas-phase reactant. In some embodiments, the fourth gas-phase reactant includes a third reducing agent. In some embodiments, the fourth gas-phase reactant includes one or both of H and / or NH. In some embodiments, the third gas-phase reactant is one of H or NH, and the fourth gas-phase reactant is the other of H and NH. For example, in some embodiments, the third gas-phase reactant includes H and the fourth gas-phase reactant includes NH. In some embodiments, a pulse of the fourth reactant is provided to a reaction space containing the substrate. In some embodiments, the substrate is moved to a reaction space containing the fourth reactant in the gas phase. Excess fourth reactant and gaseous by-products of the surface reaction, if any, are removed from the surface of the substrate.

[0044] In some embodiments, two or more of the second, third, and fourth reactants may be provided simultaneously or in overlapping pulses. For example, in some embodiments, a third reactant comprising H and a fourth reactant comprising NH are provided simultaneously or in overlapping pulses. In some embodiments, the substrate is contacted separately with the first reactant comprising a molybdenum precursor, even when contacted simultaneously with two or more additional reactants.

[0045] Although referred to as first, second, third, and fourth reactants, the reactants may be provided in different orders. In some embodiments, the molybdenum precursor is provided before any of the other reactants. In some embodiments, the molybdenum precursor is provided after one or more additional reactants. In some embodiments, the reactants are provided in the same order in each deposition cycle. In some embodiments, the reactants are provided in different orders in different deposition cycles.

[0046] The contacting and removal is repeated until a thin film of desired thickness is formed on the substrate, with each cycle leaving no more than about one monolayer in an ALD or ALD-type process, or one or more monolayers in a hybrid CVD / ALD, or cyclic CVD process.

[0047] Each reactant is introduced, or pulsed, into the chamber in the form of a vapor pulse and contacted with the surface of the substrate. In some embodiments, the surface of the substrate comprises a three-dimensional structure. In some embodiments, conditions are selected such that no more than about one monolayer of each precursor is adsorbed onto the surface of the substrate in a self-limiting manner.

[0048] Excess precursors or reactants and reaction by-products, if any, can be removed from the substrate and its surface and / or from the vicinity of the substrate and its surface between pulses of each precursor or reactant. In some embodiments, reactants and reaction by-products, if any, can be removed by purging. Purging can be accomplished, for example, using pulses of an inert gas such as nitrogen or argon.

[0049] In some embodiments, excess precursors (or reactants and / or reaction by-products, etc.) are removed from the surface of the substrate or from regions of the substrate by physically moving the substrate away from the location containing the precursors, reactants, and / or reaction by-products.

[0050] The precursors and reactants used in the method may be solid, liquid or gaseous materials under standard conditions (room temperature and atmospheric pressure), provided that they are in the vapor phase before being introduced into the reaction chamber and contacted with the surface of the substrate.

[0051] The steps of contacting the substrate with each precursor and reactant, e.g., by pulsing, and removing excess precursor or reactant and reaction by-products are repeated until a thin film of the desired thickness is formed on the substrate, with each complete cycle typically leaving no more than about one monolayer.

[0052] "Pulsing" a vaporized reactant onto a substrate means introducing the vapor into the chamber for a limited time so that the substrate is exposed to the reactant. Typically, the pulse time is from about 0.05 seconds to about 60 seconds, or longer. In some embodiments, the first reactant containing the molybdenum precursor is pulsed for about 0.05 to about 10 seconds. In some embodiments, other reactants, such as reactants containing a reducing agent, carbon, nitrogen, or hydrogen, may be pulsed for about 0.05 to about 60 seconds, or longer. However, the actual pulse time may depend on the specific reaction conditions, including the type of substrate and its surface area.

[0053] As an example, for a 300 mm wafer in a single-wafer ALD reactor, the molybdenum precursor is typically pulsed for about 0.05 seconds to about 10 seconds, while the reducing agent may be pulsed for about 0.05 to about 60 seconds. However, pulse times can be on the order of minutes in some cases. Furthermore, optimal pulse times can be readily determined by one of ordinary skill in the art based on the particular circumstances.

[0054] Those skilled in the art can determine the mass flow rates of the reactants. In some embodiments, for example, when depositing on a 300 mm wafer, the reactant flow rates are preferably from about 5 sccm to about 1000 sccm, from about 10 sccm to about 800 sccm, or from about 50 sccm to about 500 sccm.

[0055] The pressure in the reaction chamber is typically about 1 to 70 Torr, or about 2 to 40 Torr, but in some cases the pressure will be higher or lower than this range, as can be readily determined by one skilled in the art depending on multiple parameters, such as the particular reactor, method, and precursors used.

[0056] As described above, each pulse or phase of each cycle is preferably self-limiting. Excess reactants are provided in each phase to saturate susceptible structure surfaces. Surface saturation ensures reactant occupation of all available reactive sites (subject to limitations, e.g., physical size, or "steric hindrance") and therefore excellent step coverage. In some configurations, the degree of self-limiting behavior can be tuned by allowing some overlap of reactant pulses, for example, to balance deposition rate and conformality (by allowing some CVD-type reactions). Ideal ALD conditions, with reactants well separated in time and space, provide nearly complete self-limiting behavior and thus maximum conformality, but less than one monolayer per cycle due to steric hindrance. Limited CVD reactions intermixed with self-limiting ALD reactions can increase deposition rates.

[0057] In some embodiments, the reaction space can be within a single-wafer ALD reactor or a batch ALD reactor, where deposition occurs simultaneously on multiple substrates. In some embodiments, the substrate onto which deposition is desired, such as a semiconductor workpiece, is introduced into the reactor. The reactor can also be part of a cluster tool where various different processes in forming integrated circuits are performed. In some embodiments, a flow-type reactor is used. In some embodiments, a high-volume manufacturing-capable single-wafer ALD reactor is used. In other embodiments, a batch reactor containing multiple substrates is used.

[0058] Examples of suitable reactors that can be used include commercially available ALD equipment. In addition to ALD reactors, many other types of reactors capable of ALD growth of thin films can be used, including CVD reactors equipped with appropriate equipment and means for pulsing precursors. In some embodiments, a flow-type ALD reactor is used. Preferably, the reactants are kept separate until they reach the reaction chamber, minimizing shared lines for the precursors. However, other configurations are possible.

[0059] In some embodiments, a batch reactor is utilized. In some embodiments where a batch reactor is used, the wafer-to-wafer uniformity is less than 3% (1 sigma), less than 2%, less than 1%, or even less than 0.5%.

[0060] The deposition methods described herein can optionally be carried out in reactors or reaction spaces connected to a cluster tool, where each reaction space is dedicated to one type of process, allowing the temperature of the reaction space within each module to be kept constant, improving throughput compared to reactors where the substrate is heated to the process temperature before each run.

[0061] In some embodiments, Mo, MoC, MoC, MoOC, MoOCN, or MoCN thin films are deposited by a deposition cycle that includes alternately and sequentially contacting a substrate with a first reactant including a molybdenum precursor, a second reactant including carbon and oxygen, such as a second reactant including carbon monoxide (CO), and at least one third reactant including hydrogen, such as H or ammonia (NH). In some embodiments, the first reactant may be a molybdenum halide. In some embodiments, the first reactant may be a molybdenum oxyhalide. For example, in some embodiments, the first reactant may include at least one of MoOCl, MoCl, MoOCl, MoBr, or MoI. In some embodiments, the first reactant may consist of at least one of MoOCl, MoCl, MoOCl, MoBr, or MoI. In some embodiments where Mo is being deposited, the first reactant may be a molybdenum oxyhalide, e.g., a molybdenum oxychloride, such as MoOCl or MoOCl.

[0062] In some embodiments where Mo, MoC, MoOC, or MoC are being deposited, hydrogen may be used as the hydrogen-containing reactant. In some embodiments where it is desired to incorporate nitrogen into the deposited material, e.g., MoOCN, MoCN, an ammonia-containing reactant may be used as the hydrogen-containing reactant.

[0063] In some embodiments, an oxygen-containing molybdenum precursor is used, and a carbon- and oxide-containing reactant can remove oxygen from the molybdenum precursor and provide carbon to the growing MoC, MoOC, MoC, or MoCN thin film. The hydrogen reactant can remove halide ligands, and in the case of ammonia, can both remove the halide and provide nitrogen to the growing MoCN thin film. The deposition cycle is repeated to deposit a film of the desired thickness.

[0064] In some embodiments, one or more reactants (CO, H, and NH) may be provided after the molybdenum precursor. In some embodiments, the molybdenum precursor is first contacted with the substrate, followed by sequential contact with a reactant comprising carbon and an oxide, and at least one reactant, such as hydrogen or ammonia. In some embodiments, the molybdenum precursor is first contacted with the substrate, followed by sequential contact with at least one reactant, such as hydrogen or ammonia, and at least one reactant, such as carbon and an oxide.

[0065] For example, in some embodiments, a film deposition cycle includes three phases. In the first phase, the substrate is contacted only with a first reactant comprising a molybdenum precursor. In the second phase, the substrate containing the molybdenum precursor species is contacted with a second reactant comprising CO. In the third phase, the substrate is contacted with a third reactant comprising hydrogen, such as at least one of an ammonia reactant and a hydrogen reactant. In some embodiments, the second and third phases are combined, such that in the first phase, the substrate is contacted only with the molybdenum precursor, while in the second phase, the substrate is contacted with CO, H2, and / or NH3.

[0066] In some embodiments, the first reactant is provided after at least one of the other reactants. In some embodiments, the substrate is contacted with at least one of the carbon monoxide reactant, hydrogen reactant, or ammonia reactant after the first reactant. For example, in some embodiments, the carbon monoxide reactant can contact the substrate, then the first reactant can contact the substrate, and at least one of the hydrogen reactant or the ammonia reactant can contact the substrate. In some embodiments, at least one of the hydrogen reactant or the ammonia reactant can contact the substrate, then the first reactant can contact the substrate, and the carbon monoxide reactant can contact the substrate.

[0067] The deposition cycle is repeated to deposit a thin film containing molybdenum and carbon, such as a MoC, MoOC, Mo2C, MoOCN, or MoCN film of a desired thickness.

[0068] In some embodiments, MoC, MoOC, or MoC is deposited by a deposition cycle that includes alternately and sequentially contacting a substrate with a first reactant including a molybdenum precursor, a second reactant including carbon monoxide, and a third reactant including H. In some embodiments, the second reactant including carbon monoxide and the third reactant including H are provided together. That is, in some embodiments, the substrate may be contacted separately with the first reactant including a molybdenum precursor, and simultaneously with the second reactant including carbon monoxide and the third reactant including H.

[0069] In some embodiments, MoOCN or MoCN thin films are deposited by a deposition cycle comprising alternately and sequentially contacting a substrate with a first reactant comprising a molybdenum precursor, a second reactant comprising carbon monoxide, and a third reactant comprising ammonia. In some embodiments, the second reactant comprising carbon monoxide and the third reactant comprising ammonia are provided together. That is, in some embodiments, the substrate may be contacted separately with the first reactant comprising a molybdenum precursor, and simultaneously with the second reactant comprising carbon monoxide and the third reactant comprising ammonia. In some embodiments, an additional reactant comprising H2 is included in one or more deposition cycles. Thus, in some embodiments, MoOCN or MoCN thin films are deposited using at least one deposition cycle comprising alternately and sequentially contacting a substrate with a first reactant comprising a molybdenum precursor, a second reactant comprising carbon monoxide, a third reactant comprising ammonia, and a fourth reactant comprising H2. In some embodiments, two or more reactants comprising carbon monoxide, ammonia, and H2 may be provided together. For example, the substrate may be alternately and sequentially contacted with a first reactant comprising a molybdenum precursor, a second reactant comprising CO, and a reactant comprising both H and NH. The deposition cycle is repeated to deposit a film of the desired thickness. In some embodiments for depositing MoOC or MoOCN, the molybdenum precursor is a molybdenum oxyhalide, and the ratio of additional reactants is adjusted to deposit the desired material.

[0070] In some embodiments, the order of reactant provision can vary. For example, in some embodiments in a deposition cycle, each of the reactants (CO, H, and / or NH) may be provided after the first reactant, which includes the molybdenum precursor. For example, one of the carbon monoxide, hydrogen, and / or ammonia reactants contacts the substrate after the molybdenum precursor and reacts with adsorbed species of the molybdenum precursor. In some embodiments, one or more reactants may be provided before the molybdenum precursor in a deposition cycle. In that case, the reactant or reactants provided before the molybdenum precursor will react with adsorbed molybdenum species in a subsequent deposition cycle. In some embodiments, the order of additional reactants is not important. In some embodiments, the carbon monoxide reactant is provided before the H or NH reactant. In other embodiments, the H or NH reactant is provided before the carbon monoxide reactant.

[0071] In some embodiments, at least one deposition cycle may include a separate treatment phase in which the substrate is separately contacted with an oxygen-containing gas-phase reactant, such as HO, O, HO, NO, NO, or NO. This may be referred to as an oxidation phase. In some embodiments, the oxidation phase may occur after contacting the substrate with a first reactant containing a molybdenum precursor. In some embodiments, the oxidation phase may occur last in a deposition cycle. For example, a deposition cycle may include contacting the substrate with a first reactant containing a molybdenum precursor, contacting the substrate with a second reactant containing CO, contacting the substrate with a third reactant containing H and / or NH, and contacting the substrate with an oxygen-containing reactant. In some embodiments, the oxidation phase is included in one deposition cycle. In some embodiments, the oxidation phase is included in multiple deposition cycles or in each deposition cycle. In some embodiments, the oxidation phase is included at regular intervals in the deposition method.

[0072] FIG. 2 is a flowchart illustrating a deposition method 200 for depositing a molybdenum-containing thin film according to some embodiments. Referring to FIG. 2 , a molybdenum-containing thin film is deposited on a substrate in a reaction space by the deposition method 200. The deposition method 200 includes at least one deposition cycle including contacting a surface of the substrate with a first reactant including a vapor-phase molybdenum precursor at block 210, removing excess molybdenum precursor and reaction by-products, if any, from the surface at block 220, contacting the surface of the substrate with a vapor-phase second reactant at block 230, removing any excess second reactant and reaction by-products, if any, from the surface of the substrate at block 240, contacting the surface of the substrate with a vapor-phase third reactant at block 250, and removing excess third reactant and reaction by-products, if any, from the surface of the substrate at block 260. The contacting and removing steps 210-260 can be optionally repeated to form a molybdenum-containing thin film of a desired thickness at block 270. For example, Mo, MoC, Mo2C, MoOC, MoOCN, or MoCN thin films can be deposited.

[0073] In some embodiments, the molybdenum precursor comprises a molybdenum halide, as described above. In some embodiments, the molybdenum precursor may comprise a molybdenum oxyhalide. For example, the molybdenum precursor may comprise at least one of MoO2Cl2, MoCl5, MoOCl4, MoBr2, or MoI3. In some embodiments, the precursor may consist of at least one of MoO2Cl2, MoCl5, MoOCl4, MoBr2, or MoI3.

[0074] In some embodiments, the second reactant may include a first reducing agent. In some embodiments, the second reactant includes carbon and oxygen, such as carbon monoxide (CO). In some embodiments, the second reactant may consist of carbon monoxide (CO).

[0075] In some embodiments, the third reactant can include a nitrogen reactant, such as ammonia (NH3). In some embodiments, the third reactant can consist of ammonia (NH3).

[0076] In some embodiments, the third reactant can include a second reducing agent. In some embodiments, the third reactant can include hydrogen, such as H. In some embodiments, the third reactant can consist of hydrogen, such as H.

[0077] In some embodiments, Mo, MoC, MoOC, or MoC films can be deposited by the method shown in FIG. 2. In some embodiments, the molybdenum precursor includes a molybdenum halide, such as MoOCl or MoOCl, the second reactant includes CO, and the third reactant includes H. In some embodiments, the second reactant includes H and the third reactant includes CO. Deposition of MoC, MoOC, or MoC can be controlled, for example, by adjusting the ratio of the second reactant to the third reactant throughout the deposition process. That is, in some deposition cycles, the second reactant or the third reactant can be omitted to adjust the ratio of the time the substrate is in contact with the second reactant and the third reactant throughout the deposition process.

[0078] In some embodiments, the only reactants used in the deposition cycle are the molybdenum precursor, CO, and H2.

[0079] In some embodiments, MoCN thin films can be deposited. In some embodiments, the molybdenum precursor comprises a molybdenum halide such as MoOCl4 or MoO2Cl2, the second reactant comprises CO, and the third reactant comprises NH3. In some embodiments, the second reactant comprises NH3 and the third reactant comprises CO.

[0080] In some embodiments, the only reactants used in the deposition cycle are the molybdenum precursor, CO, and NH3.

[0081] In some embodiments, the cyclic deposition method 200 may be an ALD-type process. In some embodiments, the cyclic deposition process 200 may be an ALD process. In some embodiments, the cyclic process 200 may be a hybrid ALD / CVD or cyclic CVD process.

[0082] Although the illustrated deposition cycle begins with contacting 210 the surface of the substrate with a first reactant comprising a gas-phase molybdenum precursor, in other embodiments the deposition cycle may begin with contacting 230 the surface of the substrate with a second reactant or contacting 250 the surface of the substrate with a third reactant.

[0083] In some embodiments, removing the precursors, or reactants, and any excess reaction by-products at blocks 220, 240, and 260 may include purging the reaction space, or reaction chamber. Purging the reaction chamber may involve the use of a purge gas and / or applying a vacuum to the reaction space. If a purge gas is used, the purge gas may flow continuously or may flow through the reaction space only after the flow of a reactant gas has stopped and before the next reactant gas begins flowing through the reaction space. It is also possible to continuously flow a purge or non-reactive gas through the reaction chamber to utilize a non-reactive gas as a carrier gas for various reactants. Thus, in some embodiments, a gas such as nitrogen flows continuously through the reaction space, and the molybdenum precursor and reactants are pulsed into the reaction chamber as needed. Because the carrier gas flows continuously, removing excess reactants or reaction by-products is accomplished by simply stopping the flow of reactant gas into the reaction space.

[0084] In some embodiments, removing precursors, or reactants, and any excess reaction by-products at blocks 220, 240, 260 can include moving the substrate from a first reaction chamber to a second, different reaction chamber. In some embodiments, removing precursors, or reactants, and any excess reaction by-products at blocks 220, 240, 260 can include moving the substrate from a first reaction chamber to a second, different reaction chamber under vacuum.

[0085] In some embodiments, the deposited molybdenum-containing thin film can be subjected to a treatment process after deposition. In some embodiments, the treatment process can, for example, increase the electrical conductivity or continuity of the deposited molybdenum-containing thin film. In some embodiments, the treatment process can include, for example, an annealing process.

[0086] 3 is a flowchart illustrating a deposition method 300 for depositing a molybdenum-containing thin film according to some embodiments. Deposition method 300 is similar to deposition method 200, except that a second reactant and a third reactant simultaneously contact the substrate, such as by co-flowing them together in a reaction space. Deposition method 300 includes at least one deposition cycle that includes contacting a surface of the substrate with a first reactant including a vapor-phase molybdenum precursor at block 310, removing excess molybdenum precursor and reaction by-products, if any, from the surface at block 320, simultaneously contacting the surface of the substrate with a vapor-phase second reactant and a vapor-phase third reactant at block 330, and removing excess second reactant, third reactant, and reaction by-products, if any, from the surface of the substrate at block 340. The deposition cycle, including the contacting and removing steps 310-340, can be repeated to form a molybdenum-containing thin film of a desired thickness at block 350. For example, Mo, MoC, Mo2C, MoOC, MoOCN, or MoCN thin films can be deposited.

[0087] As shown in Figure 3, in some embodiments, the molybdenum precursor includes molybdenum oxychloride. However, other molybdenum precursors may be used. In some embodiments, the molybdenum precursor may include a molybdenum halide, such as a molybdenum oxyhalide. For example, the molybdenum precursor may include at least one of MoO2Cl2, MoCl5, MoOCl4, MoBr2, or MoI3. For example, the precursor may consist of at least one of MoO2Cl2, MoCl5, MoOCl4, MoBr2, or MoI3.

[0088] In some embodiments, the second reactant may include a first reducing agent. In some embodiments, the second reactant includes carbon. In some embodiments, the second reactant includes carbon and oxygen, such as carbon monoxide (CO). In some embodiments, the third reactant may include nitrogen, such as ammonia (NH). In some embodiments, the third reactant may include a second reducing agent. In some embodiments, the third reactant may include hydrogen, such as H. In some embodiments, the second reactant may include CO and the third reactant may include NH. In some embodiments, the second reactant may include CO and the third reactant may include H. In some embodiments, the second reactant may include CO and the third reactant may include both NH and H.

[0089] Thus, in some embodiments, the second reactant and the third reactant may comprise CO and H2, which may flow together into the reaction space. In some embodiments, the second reactant and the third reactant may comprise CO and NH3, which may flow together into the reaction space. In some embodiments, the molybdenum precursor and / or one or more of the reactants may be supplied with a carrier gas. In some embodiments, the co-flow of the second reactant and the third reactant may consist of CO and H2. In some embodiments, the co-flow of the second reactant and the third reactant may consist of CO and NH3.

[0090] In some embodiments, MoC or MoC films can be deposited. In some embodiments, the molybdenum precursor can include MoOCl or MoOCl, and the co-flow of the second and third reactants can include CO and H. Deposition of MoC, MoOC, or MoC can be controlled by adjusting the ratio of the second and third reactants.

[0091] In some embodiments, MoOCN or MoCN films may be deposited. In some embodiments, the molybdenum precursor includes MoOCl4 or MoO2Cl2, and the co-flowing second and third reactants may include CO and NH3. In some embodiments, the third reactant includes NH3 and H2, such that CO, NH3, and H2 are flowed together.

[0092] 4 is a flow chart illustrating a deposition method 400 for depositing a thin film comprising molybdenum, according to some embodiments. The deposition method 400 is similar to the deposition method 200, except that an additional fourth reactant is further used. Deposition method 400 includes at least one deposition cycle including contacting a surface of a substrate with a first reactant comprising a vapor-phase molybdenum precursor at block 410, removing excess molybdenum precursor and reaction by-products, if any, from the surface at block 420, contacting the surface of the substrate with a vapor-phase second reactant at block 430, removing any excess second reactant and reaction by-products, if any, from the surface of the substrate at block 440, contacting the surface of the substrate with a vapor-phase third reactant at block 450, removing any excess third reactant and reaction by-products, if any, from the surface of the substrate at block 460, contacting the surface of the substrate with a vapor-phase fourth reactant at block 470, and removing any excess fourth reactant and reaction by-products, if any, from the surface of the substrate at block 480. The contacting and removing steps may be repeated at block 490 to form a thin film comprising molybdenum of a desired thickness. For example, MoOCN or MoCN thin films can be deposited.

[0093] In some embodiments, the molybdenum precursor may include a molybdenum halide or a molybdenum oxyhalide. For example, the molybdenum precursor may include at least one of MoO2Cl2, MoCl5, MoOCl4, MoBr2, or MoI3.

[0094] In some embodiments, the second reactant may include a first reducing agent. In some embodiments, the second reactant may include carbon. In some embodiments, the second reactant may include carbon and oxygen, such as carbon monoxide (CO), the third reactant may include nitrogen, such as ammonia (NH), and the fourth reactant may include a second reducing agent, such as hydrogen (H). In some embodiments, the second reactant may consist of carbon monoxide (CO), the third reactant may consist of ammonia (NH), and the fourth reactant may consist of hydrogen (H).

[0095] In some embodiments, the second reactant may comprise carbon and oxygen, such as carbon monoxide (CO), the third reactant may comprise hydrogen (H), and the fourth reactant may comprise nitrogen, such as ammonia (NH). In some embodiments, the second reactant may consist of carbon and oxygen, such as carbon monoxide (CO), the third reactant may consist of hydrogen (H), and the fourth reactant may consist of ammonia (NH).

[0096] In some embodiments, the second reactant may include hydrogen (H), the third reactant may include carbon and oxygen such as carbon monoxide (CO), and the fourth reactant may include nitrogen such as ammonia (NH). In some embodiments, the second reactant may consist of hydrogen (H), the third reactant may consist of carbon and oxygen such as carbon monoxide (CO), and the fourth reactant may consist of nitrogen such as ammonia (NH).

[0097] In some embodiments, the second reactant may include hydrogen (H), the third reactant may include nitrogen, such as ammonia (NH), and the fourth reactant may include carbon and oxygen, such as carbon monoxide (CO). In some embodiments, the second reactant may consist of hydrogen (H), the third reactant may consist of nitrogen, such as ammonia (NH), and the fourth reactant may consist of carbon and oxygen, such as carbon monoxide (CO).

[0098] In some embodiments, the second reactant may comprise nitrogen, such as ammonia (NH), the third reactant may comprise carbon and oxygen, such as carbon monoxide (CO), and the fourth reactant may comprise hydrogen (H). In some embodiments, the second reactant may consist of nitrogen, such as ammonia (NH), the third reactant may consist of carbon and oxygen, such as carbon monoxide (CO), and the fourth reactant may consist of hydrogen (H).

[0099] In some embodiments, the second reactant may comprise nitrogen, such as ammonia (NH), the third reactant may comprise hydrogen (H), and the fourth reactant may comprise carbon and oxygen, such as carbon monoxide (CO). In some embodiments, the second reactant may consist of nitrogen, such as ammonia (NH), the third reactant may consist of hydrogen (H), and the fourth reactant may consist of carbon and oxygen, such as carbon monoxide (CO).

[0100] In some embodiments, H2 may be co-flowed with NH3 in any of the deposition methods, for example, in steps 200, 300, or 400 of Figures 2, 3, and 4, respectively.

[0101] In some embodiments, an oxidation process can be performed, for example, before block 230. For example, in the oxidation process, HO, O, HO, NO, NO, or NO may contact the substrate. For example, a molybdenum precursor including MoOCl can be dissociated in the oxidation step to form MoO and release HCl gas and O. After the oxidation process, MoO can be reduced to form a Mo film using a second reactant and / or a third reactant, i.e., CO and H and / or NH. In some embodiments, the oxidation process can include co-flow of HO and H.

[0102] Thin film properties The thin film deposited according to some embodiments described herein may be a continuous thin film containing molybdenum. In some embodiments, the thin film containing molybdenum may be continuous with a thickness of less than about 100 nm, less than about 60 nm, less than about 50 nm, less than about 40 nm, less than about 30 nm, less than about 25 nm, or less than about 20 nm, or less than about 15 nm, or less than about 10 nm, or less than about 5 nm, or less. The continuity referred to may be physical continuity or electrical continuity. In some embodiments, the thickness at which a film can be physically continuous may not be the same as the thickness at which the film is electrically continuous, and the thickness at which a film can be electrically continuous may not be the same as the thickness at which the film is physically continuous.

[0103] While in some embodiments, thin films comprising molybdenum deposited according to some embodiments described herein can be continuous, in some embodiments it may be desirable to form discontinuous thin films comprising molybdenum, or thin films comprising discrete islands comprising molybdenum, or thin films comprising nanoparticles comprising molybdenum. In some embodiments, deposited thin films comprising molybdenum may include nanoparticles comprising molybdenum that are not substantially physically or electrically continuous with one another. In some embodiments, deposited thin films comprising molybdenum may include discrete nanoparticles or discrete islands comprising molybdenum.

[0104] In some embodiments, thin films comprising molybdenum deposited according to some embodiments described herein can have a resistivity of less than about 20 μΩcm at a thickness of less than about 100 nm. In some embodiments, thin films comprising molybdenum deposited according to some embodiments described herein can have a resistivity of less than about 20 μΩcm at a thickness of less than about 60 nm, less than about 50 nm, less than about 40 nm, less than about 30 nm, less than about 25 nm, or less than about 20 nm or less. In some embodiments, thin films comprising molybdenum deposited according to some embodiments described herein can have a resistivity of less than about 15 μΩcm at a thickness of less than about 60 nm, less than about 50 nm, less than about 40 nm, less than about 30 nm, less than about 25 nm, or less than about 20 nm or less. In some embodiments, thin films comprising molybdenum deposited according to some embodiments described herein can have a resistivity of less than about 10 μΩ cm at a thickness of less than about 60 nm, less than about 50 nm, less than about 40 nm, less than about 30 nm, less than about 25 nm, or less than about 20 nm or less. In some embodiments, thin films comprising molybdenum deposited according to some embodiments described herein can have a resistivity of less than about 200 μΩ cm at a thickness of less than about 30 nm, less than about 20 nm, less than about 15 nm, less than about 10 nm, less than about 8 nm, or less than about 5 nm or less.

[0105] In some embodiments, thin films comprising molybdenum deposited according to some embodiments described herein can have a resistivity of less than about 200 μΩcm, less than about 100 μΩcm, less than about 50 μΩcm, less than about 30 μΩcm, less than about 20 μΩcm, less than about 18 μΩcm, less than about 15 μΩcm, less than about 12 μΩcm, less than about 10 μΩcm, less than about 8 μΩcm, or less than about 5 μΩcm at a thickness of about 100 nm. In some embodiments, thin films comprising molybdenum deposited according to some embodiments described herein can have a resistivity of less than about 20 μΩcm, less than about 18 μΩcm, less than about 15 μΩcm, less than about 12 μΩcm, less than about 10 μΩcm, less than about 8 μΩcm, or less than about 5 μΩcm at a thickness of less than about 50 nm.

[0106] In some embodiments, the MoC, Mo2C, MoOC, MoOCN, or MoCN film is deposited to a thickness of less than about 10 nm, more preferably less than about 5 nm, and most preferably less than about 3 nm.

[0107] Atomic layer deposition allows for conformal deposition of Mo, MoC, MoC, MoOC, MoOCN, or MoCN films. In some embodiments, Mo, MoC, MoC, or MoCN films deposited by the methods disclosed herein on three-dimensional structures have at least 90%, 95%, or more conformality. In some embodiments, the films are about 100% conformal.

[0108] In some embodiments, the formed Mo, MoC, MoC, MoOC, MoOCN, or MoCN films have step coverage of greater than about 80%, more preferably greater than about 90%, and most preferably greater than about 95% in structures having high aspect ratios. In some embodiments, high aspect ratio structures have aspect ratios of greater than about 3:1 when comparing the depth or height to the width of the feature. In some embodiments, the structures have aspect ratios of greater than about 5:1, or even 10:1 or greater.

[0109] In some embodiments, molybdenum films, such as Mo, MoC, MoC, MoOC, MoOCN, or MoCN films deposited by the methods disclosed herein, are treated after deposition, such as by annealing, as desired for the application. In some embodiments, the Mo, MoC, MoC, MoOC, MoOCN, or MoCN films are annealed in an oxygen environment. For example, the films may be annealed at high temperatures in water or O. In some embodiments, no annealing step is performed.

[0110] In some embodiments, after deposition of the molybdenum film, such as a Mo, MoC, MoC, or MoCN deposition, an additional film is deposited. In some embodiments, the additional film may be in direct contact with the molybdenum film, such as in direct contact with the Mo, MoC, MoC, MoOC, MoOCN, or MoCN layer.

[0111] While particular embodiments and examples have been discussed, those skilled in the art will recognize that the scope of the claims extends beyond the specifically disclosed embodiments to other alternative embodiments and / or uses and obvious modifications, and their equivalents.

Claims

1. 1. A method for forming a thin film comprising molybdenum and carbon on a substrate in a reaction space, said method comprising a deposition cycle: The deposition cycle involves contacting the substrate with a first reactant comprising a vapor phase molybdenum precursor comprising a molybdenum halide, and then contacting the substrate with a second reactant comprising CO and H ２ and simultaneously contacting the reactant with a third reactant comprising The method wherein the deposition cycle is repeated two or more times to form a thin film comprising molybdenum and carbon.

2. 10. The method of claim 1, wherein the deposition cycle further comprises removing excess vapor-phase molybdenum precursor and reaction by-products, if present, from the reaction space after contacting the substrate with the first reactant and before contacting the substrate with the second reactant and the third reactant.

3. The molybdenum precursor is MoCl ５ and MoBr ２ and MoI ３ The method of claim 1 , comprising at least one of:

4. The method of claim 1 , wherein the molybdenum precursor comprises a molybdenum oxyhalide.

5. The molybdenum precursor is MoOCl ４ and MoO ２ Cl ２ The method of claim 4 , comprising at least one of:

6. The thin film containing molybdenum and carbon is MoC and Mo ２ 10. The method of claim 1, comprising one of C and MoOC.

7. The deposition cycle comprises treating the substrate with NH ３ 10. The method of claim 1, further comprising contacting the hydroxyl group with a fourth reactant comprising:

8. 8. The method of claim 7, wherein the thin film comprising molybdenum and carbon comprises one of MoOCN and MoCN.

9. The reactants used in the deposition cycle are the molybdenum precursor, CO and H ２ The method of claim 1 , wherein only

10. The method of claim 1 further comprising contacting the substrate with an oxygen reactant.

11. The oxygen reactant is H ２ O and O ３ and H ２ O ２ and N ２ O and NO ２ and NO.

12. The third reactant further comprises NH ３ The method of claim 1 , comprising:

13. The method of claim 1 further comprising depositing a cobalt-containing film on the thin film comprising molybdenum and carbon.

14. The deposition cycle comprises, in order: contacting the substrate with a first reactant comprising the vapor phase molybdenum precursor; and contacting the substrate with the second reactant and the third reactant simultaneously.

15. The method of claim 1 , wherein the method is an atomic layer deposition method.

16. 1. A vapor deposition method for forming a thin film comprising molybdenum, carbon, and nitrogen on a substrate in a reaction space, the vapor deposition method comprising a deposition cycle, the deposition cycle comprising: contacting the substrate with a vapor-phase first reactant comprising a vapor-phase molybdenum halide; The substrate is then treated with a second reactant comprising CO and NH ３ and simultaneously contacting the reactant with a third reactant comprising: repeating the deposition cycle to form a thin film comprising molybdenum, carbon, and nitrogen.

17. 17. The vapor deposition method of claim 16, wherein the deposition cycle further comprises removing excess first reactant and reaction by-products, if present, from the reaction space after contacting the substrate with the first reactant and before contacting the substrate with the second reactant or third reactant.

18. The molybdenum halide is MoCl ５ , MoBr ２ , MoI ３ , MoOCl ４ , or MoO ２ Cl ２ 17. The deposition method of claim 16, comprising: 【Request Item 19】 The reactants used in the deposition cycle are the molybdenum halide, CO, and NH ３ The vapor deposition method according to claim 16, wherein only 【Request Item 20】 The third reactant further comprises H ２ 17. The deposition method of claim 16, comprising: 【Request Item 21】 The reactants used in the deposition cycle are the molybdenum halide, CO, and NH ３ and H ２ The vapor deposition method according to claim 16, wherein only

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