阅读说明：本技术 包含钼的膜的气相沉积 (Vapor deposition of films comprising molybdenum ) 是由 B.佐普 E.C.史蒂文斯 S.斯瓦米纳坦 E.J.希罗 R.B.米利根 于 2021-06-21 设计创作，主要内容包括：提供了用于在衬底上形成包含钼的薄膜的气相沉积过程。在一些实施例中,该过程包括多个沉积循环,其中衬底分别与包含卤化钼的气相钼前体、包含CO的第一反应物和包含H-(2)的第二反应物接触。在一些实施例中,薄膜包括MoC、Mo-(2)C或MoOC。在一些实施例中,衬底另外与氮反应物接触,并且沉积包括钼、碳和氮的薄膜,例如MoCN或MoOCN。(A vapor deposition process for forming a molybdenum-containing thin film on a substrate is provided. In some embodiments, the process includes a plurality of deposition cycles in which the substrate is separately contacted with a vapor phase molybdenum precursor comprising a molybdenum halide, a first reactant comprising CO, and a gas phase comprising H 2 Is contacted with the second reactant. In some embodiments, the thin film comprises MoC, Mo 2 C or MoOC. In some embodiments, the substrate is additionally contacted with a nitrogen reactant and a thin film comprising molybdenum, carbon, and nitrogen, such as MoCN or MoOCN, is deposited.)

1. A process for forming a molybdenum-containing thin film on a substrate in a reaction space, the process comprising a deposition cycle comprising:

contacting a substrate with a first reactant comprising a vapor phase molybdenum precursor comprising a molybdenum halide, followed by contacting the substrate with a second reactant comprising CO and a reaction product comprising H₂Is contacted with the third reactant of (a),

wherein the deposition cycle is repeated two or more times to form a molybdenum-containing thin film.

2. The process of claim 1, wherein the thin film comprises molybdenum and carbon.

3. The process of claim 1, wherein the substrate is in alternating and sequential contact with the first, second and third reactants.

4. The process of claim 1, wherein the substrate is simultaneously contacted with the second reactant and a third reactant.

5. The process of claim 1, wherein the deposition cycle further comprises removing excess vapor phase molybdenum precursor and reaction byproducts, if present, from the reaction space after the substrate is contacted with the first reactant and before the substrate is contacted with the second and third reactants.

6. The process of claim 1, wherein the molybdenum precursor comprises MoCl₅、MoBr₂Or MoI₃At least one of (1).

7. The process of claim 1, wherein the molybdenum precursor comprises molybdenum oxyhalide.

8. The process of claim 7, wherein the molybdenum precursor comprises MoOCl₄Or MoO₂Cl₂At least one of (1).

9. The process of claim 8, wherein the film is a molybdenum film.

10. The process of claim 1, wherein the thin film comprising molybdenum and carbon comprises MoC, Mo₂C and MoOC.

11. The process of claim 1, wherein the depositing further comprises exposing the substrate to a solution containing NH₃Is contacted with the fourth reactant.

12. The process of claim 11, wherein the thin film comprising molybdenum and carbon comprises one of MoOCN or MoCN.

13. The process of claim 1, wherein the only reactants used in the deposition cycle are the molybdenum precursor, CO, and H₂。

14. The process of claim 1, further comprising contacting the substrate with an oxygen reactant.

15. The process of claim 14, wherein the oxygen reactant comprises H₂O、O₃、H₂O₂、N₂O、NO₂Or NO.

16. The process of claim 1, wherein the deposition cycle comprises, in order:

contacting the substrate with a first reactant comprising a vapor phase molybdenum precursor;

contacting the substrate with a second gas phase reactant comprising CO; and

contacting the substrate with a solution comprising H₂Is contacted with the third gas phase reactant.

17. The process of claim 1, wherein the third reactant further comprises NH₃。

18. The process of claim 1, further comprising depositing a cobalt-containing film on the thin film comprising molybdenum and carbon.

19. The process of claim 1, wherein the deposition cycle comprises, in order:

contacting the substrate with a first reactant comprising a vapor phase molybdenum precursor; and

the substrate is contacted with the second reactant and the third reactant simultaneously.

20. The process of claim 1, wherein the process is an atomic layer deposition process.

21. A vapor deposition process for forming a thin film comprising molybdenum, carbon, and nitrogen on a substrate in a reaction space, the vapor deposition process comprising a deposition cycle comprising:

contacting a substrate with a first reactant comprising a vapor phase molybdenum halide;

subsequently contacting the substrate with a second reactant comprising CO and a reactant comprising NH₃(iii) contacting the third reactant; and

the deposition cycle is repeated to form a film comprising molybdenum, carbon, and nitrogen.

22. The vapor deposition process of claim 21, wherein the deposition cycle further comprises removing excess first reactant and reaction byproducts, if present, from the reaction space after the substrate is contacted with the first reactant and before the substrate is contacted with the second reactant or third reactant.

23. The vapor deposition process of claim 21, wherein the molybdenum halide comprises MoCl₅、MoBr₂、MoI₃、MoOCl₄Or MoO₂Cl₂。

24. The vapor deposition process of claim 21, wherein the only reactants used in the deposition cycle are the molybdenum halide, CO, and NH₃。

25. A vapour deposition process according to claim 21, wherein the third reactant additionally comprises H₂。

26. The vapor deposition process of claim 21, wherein the only reactants used in the deposition cycle are the molybdenum halide, CO, NH₃And H₂。

Technical Field

The present application relates generally to vapor deposition processes for forming films comprising molybdenum. The molybdenum-carbon containing thin film may be deposited by a cyclic vapor deposition process, such as atomic layer deposition, for example using CO and H₂As a reducing agent.

Background

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, barrier/adhesion layers, etc. TiN films, however, have relatively high resistivity and cannot be extended to the higher p-metal work function requirements for advanced IC nodes. Molybdenum carbide films may be substituted for TiN films. However, deposition processes that utilize halogenated reactants to form molybdenum films often have the disadvantage of etching or contaminating other materials.

Disclosure of Invention

In one aspect, a vapor deposition method for depositing a film comprising molybdenum is provided. In some embodiments, the thin film comprises molybdenum and carbon, such as molybdenum carbide (MoC, Mo) provided by a vapor deposition process₂C) A film, a molybdenum oxycarbide (MoOC) film, a molybdenum oxycarbonitride (MoOCN) film, or a molybdenum carbonitride (MoCN) film. In some embodiments, the deposition process is an Atomic Layer Deposition (ALD) process.

In some embodiments, a vapor deposition process for forming a molybdenum-containing film (such as a molybdenum and carbon-containing film) on a substrate in a reaction space includes a plurality of deposition cycles including contacting the substrate with a first reactant comprising a vapor-phase molybdenum precursor (such as a molybdenum halide), followed by contacting the substrate with a vapor-phase second reactant comprising, for example, carbon and oxygen (such as CO) and hydrogen (such as H)₂) Is contacted with the gaseous third reactant. The deposition cycle may be repeated two or more times to form a molybdenum-containing film. In some embodiments, the thin film comprises molybdenum and carbon. In some embodiments, the substrate is contacted with the first reactant, the second reactant, and the third reactant alternately and sequentially. In some embodiments, the substrate is contacted with the first reactant, followed by simultaneous contact with the second and third reactants.

In some embodiments, the thin film is MoC, Mo₂C or MoOC film. In some embodiments, the film is a MoOCN or MoCN film. In some embodiments, the film is a molybdenum film.

In some embodiments, the molybdenum precursor is a molybdenum halide, such as MoCl₅、MoBr₂Or MoI₃. In some embodiments, the molybdenum precursor is a molybdenum oxyhalide, such as MoOCl₄Or MoO₂Cl₂。

In some embodiments, the only reactants used in the deposition cycle are the molybdenum precursor, the second reactant, and the third reactant. In some embodiments, the only reactants used in the deposition cycle are the molybdenum precursor, CO, and H₂。

In some embodiments, the deposition process further comprises contacting the substrate with one or more additional reactants. In some embodiments, the fourth reactant comprises nitrogen, e.g., comprises NH₃The fourth reactant of (1). In some embodiments, the fourth reactant comprises oxygen. In some embodiments, the substrate is reacted with an oxygen reactant such as H₂O、O₃、H₂O₂、N₂O、NO₂Or NO contact. In some embodiments, the substrate is contacted with the fourth reactant after the substrate is contacted with the first reactant and before the substrate is contacted with the second and third reactants. In some embodiments, the substrate is contacted with the fourth reactant after being contacted with the first, second, and third reactants.

In some embodiments, the deposition cycle comprises, in order, contacting the substrate with a first reactant comprising a molybdenum precursor, contacting the substrate with a second reactant (such as CO), and contacting the substrate with a third reactant (such as H)₂) And (4) contacting. In some embodiments, the deposition cycle comprises, in sequence, contacting the substrate with the first precursor, followed by simultaneously contacting the substrate with the second and third reactants. In some embodiments, the third reactant further comprises NH₃. In some embodiments, the substrate is separate from the substrate and comprises NH₃Is contacted with the fourth reactant.

In some embodiments, a cobalt film is deposited on the molybdenum-containing film.

In some embodiments, for depositing molybdenum carbide orThe deposition cycle of molybdenum oxycarbide comprises, in order: 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 second reactant comprising H₂Is contacted with the third reactant. In some embodiments, the deposition cycle comprises, in sequence, contacting the substrate with the first precursor, followed by simultaneously contacting the substrate with the second and third reactants.

In some embodiments, a process for forming a thin film comprising molybdenum, carbon, and nitrogen on a substrate in a reaction space includes a deposition cycle comprising contacting the substrate with a first reactant comprising a molybdenum precursor (such as a molybdenum halide), followed by contacting the substrate with a second reactant comprising CO and a reaction mixture comprising NH₃Is contacted with the third reactant.

The deposition cycle may be repeated two or more times to form a thin film of a desired thickness. In some embodiments, after each contacting step, e.g., after the substrate is contacted with the first reactant and before the substrate is contacted with the second and/or third reactant, excess reactant and reaction byproducts, if present, are removed from the reaction space.

In some embodiments, the only reactants used in the deposition cycle are molybdenum halide, CO, and H₂. In some embodiments, the only reactants used in the deposition cycle are molybdenum halide, CO, and NH₃. In some embodiments, the third reactant comprises NH₃And H₂. In some embodiments, the only reactants used in the deposition cycle are molybdenum halide, CO, H₂And NH₃。

Drawings

The embodiments described herein will be better understood from the detailed description and the accompanying drawings, which are intended to illustrate and not to limit the invention, and in which:

fig. 1A is a simplified cross-sectional view of a semiconductor device structure according to some embodiments.

Fig. 1B is a simplified cross-sectional view of a gap-fill structure according to some embodiments.

Fig. 2 is a flow diagram illustrating a process of depositing a metal film comprising molybdenum and carbon by Atomic Layer Deposition (ALD) deposition, in accordance with certain embodiments.

Fig. 3 is a flow diagram illustrating a process of depositing a metal film comprising molybdenum and carbon by Atomic Layer Deposition (ALD) deposition, in accordance with certain embodiments.

Fig. 4 is a flow diagram illustrating a process of depositing a metal film comprising molybdenum and carbon by Atomic Layer Deposition (ALD) deposition, in accordance with certain embodiments.

Detailed Description

Vapor deposition processes can be used to deposit materials comprising molybdenum, such as films comprising molybdenum, films comprising molybdenum and carbon, and films comprising molybdenum, carbon, and nitrogen. In some embodiments, the vapor deposition process utilizes 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, such as CO. In some embodiments, the third reactant comprises H₂And/or NH₃. In some embodiments, the third gas phase reactant may comprise hydrazine. In some embodiments, additional reactants are utilized, and may also include, for example, H₂And/or NH₃. In some embodiments, additional reactants comprising oxygen, such as H, may be utilized₂O、O₃、H₂O₂、N₂O、NO₂Or NO. In some embodiments, a film comprising molybdenum, such as a molybdenum film, a film comprising molybdenum and carbon, such as molybdenum carbide (e.g., MoC, Mo) is deposited by a vapor deposition process₂C) A film, a molybdenum oxycarbide (MoOC) film, or a film comprising molybdenum, carbon, and nitrogen, such as a molybdenum oxycarbonitride (MoOCN) film or a molybdenum carbonitride (MoCN) film. In some embodiments, the vapor deposition process is an Atomic Layer Deposition (ALD) process.

In some embodiments, a thin film comprising molybdenum or molybdenum and carbon, such as molybdenum carbide, molybdenum oxycarbide, molybdenum carbonitride, or molybdenum oxycarbonitride, is deposited by the disclosed methods and may be used in various circumstances, for example, as a gate material in a CMOS structure or as a barrier/adhesion layer for a gap-fill structure, for example, as shown in fig. 1A and 1B. In some embodiments, the film may be used as an adhesion layer during a cobalt gap fill process. In some embodiments, the thin film may be used as a low resistivity pmos metal for a metal gate. In some embodiments, the thin film may be used as a low resistivity barrier or nucleation layer for metallization in logic or memory applications.

As a non-limiting example, fig. 1A is a simplified cross-sectional view of a semiconductor device structure 100 according to some embodiments, and fig. 1B is a simplified cross-sectional view of a gap-fill structure 120 according to some embodiments. Referring to fig. 1A, a semiconductor device structure 100 includes a substrate 102 and a gate structure 103 on the substrate 102. Gate structure 103 includes a gate dielectric layer 104 on a substrate, a layer including molybdenum and carbon (e.g., MoC, Mo) on gate dielectric layer 104₂C. MoOC, MoOCN, or MoCN) and a conductive layer 108 on gate metal layer 106. Spacers 110 may be formed on sidewalls of gate dielectric layer 104, gate metal layer 106, and conductive layer 108. In some embodiments, the gate metal layer 106 may include molybdenum and carbon, and may be formed by a vapor deposition process as described herein, such as by an atomic layer deposition process. In some embodiments, the gate metal layer 106 may include molybdenum oxycarbide.

Referring to FIG. 1B, the gap-fill structure 120 includes a substrate 122, a dielectric layer 124, a dielectric layer containing molybdenum and carbon (e.g., MoC, Mo)₂C. MoOC, MoOCN, or MoCN) barrier/adhesion layer 126 and gap fill layer 128. The dielectric layer 124 is patterned and a barrier/adhesion layer 126 is conformally formed on the patterned dielectric layer, e.g., on the bottom and sides of the recess. The gap filling layer 128 fills the recess. In some embodiments, the barrier/adhesion layer 126 may be formed by a vapor deposition process as described herein, such as by an atomic layer deposition process. In some embodiments, the gap fill layer 128 comprises cobalt. In some embodiments, barrier/adhesion layer 126 may include molybdenum oxycarbide.

Contains molybdenum and carbon (e.g., MoC, Mo) in contrast to TiN, which is typically used in these cases₂C. MoOC, MoOCN, or MoCN) and a gate metal layer 106 comprising molybdenum and carbon (e.g., MoC, MoCN, or MoCN),Mo₂C. MoOC, MoOCN, or MoCN) barrier/adhesion layer 126 may provide low resistivity. Other situations where the disclosed molybdenum and carbon containing films can be used will be apparent to the skilled person.

Atomic Layer Deposition (ALD)

As mentioned above, a vapor deposition process is provided for depositing a material comprising molybdenum or molybdenum and carbon, such as MoC, Mo₂C. MoOC, MoOCN or MoCN films. In some embodiments, the vapor deposition process is an atomic layer deposition process in which the substrate surface is alternately and sequentially contacted with two or more reactants.

In some embodiments, a material comprising molybdenum is deposited on the substrate in the reaction space by contacting the substrate surface 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 H₂And/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 reductant is different from the second reductant. In some embodiments, the first reducing agent and the second reducing agent are the same. In some embodiments, the first reductant may include 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 process includes a deposition cycle in which the substrate in the reaction chamber is contacted alternately and sequentially 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, a substrate in a reaction chamber is contacted with a first reactant comprising a vapor phase molybdenum precursor, a second reactant comprising CO, and a reaction mixture comprising H₂Alternately and sequentially. In some embodiments, the substrate is contacted with the second and third reactants simultaneously. The deposition cycle may be repeated two or more times to deposit a film of a desired thickness.

Although referred to as a first reactant, a second reactant, and a third reactant, they need not be in contact with the substrate in that order during a deposition cycle. In some embodiments, the reactants are contacted with the substrate in the order of the first reactant, the second reactant, and the third reactant. In some embodiments, the substrate is contacted with one or both of the second or third reactants prior to contacting with the first reactant. In some embodiments, the substrate is sequentially contacted with a first reactant comprising a molybdenum precursor, and then contacted with a second and third reactant.

In some embodiments, the substrate is first contacted with a first reactant comprising a molybdenum precursor, and then subsequently contacted with a second and third reactant, e.g., CO and H₂While in contact. In some embodiments, the first, second, and third reactants comprising the molybdenum precursor are the only reactants used in the deposition cycle. In some embodiments, the molybdenum precursor, CO, and H₂Is the only reactant used in the deposition cycle. In some embodiments, a molybdenum precursor, CO, and H are used₂The deposited film comprises Mo, MoC, Mo₂C or MoOC. In some embodiments, CO and H₂The ratio of (d) can be adjusted to deposit MoOC. For example, the adjustment may be achieved by adjusting the exposure time of the substrate to each reactant or by adjusting the ratio of the reactants provided throughout the deposition process.

In some embodiments, the substrate is treated by contacting the substrate surface with a first reactant comprising a molybdenum precursor, a second reactant comprising a first reducing agent, and a nitrogen-containing reactant such as NH₃Is contacted with a substrate in the reaction space to deposit a material comprising molybdenum, carbon and nitrogen on the substrate in the reaction space. In some embodiments, the deposition process includes a deposition cycle in which the substrate is alternately and sequentially contacted with a first reactant comprising a vapor phase molybdenum precursor, a second reactant comprising carbon, such as CO, and a first reactant comprising nitrogen, such as NH₃Is contacted with the third reactant. 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 film of a desired thickness.

Although referred to as a first reactant, a second reactant, and a third reactant, they need not be in contact with the substrate in that order during a deposition cycle. In some embodiments, the reactants are contacted with the substrate in the order of the first reactant, the second reactant, and the third reactant. In some embodiments, the substrate is contacted with one or both of the second or third reactants prior to contacting with the first reactant. In some embodiments, the substrate is sequentially contacted with a first reactant comprising a molybdenum precursor, and then contacted with a second and third reactant.

In some embodiments, the deposition process includes a deposition cycle in which the substrate is coated with a coating comprising a vapor phase molybdenum precursor, CO, and NH₃Alternately and sequentially. In some embodiments, the substrate is CO and NH₃While in contact. In some embodiments, the substrate is sequentially contacted with a first reactant comprising a molybdenum precursor, and then contacted with a second and third reactant. In some embodiments, the substrate is first contacted with a first reactant comprising a molybdenum precursor, and then subsequently contacted with second and third reactants, e.g., CO and NH₃While in contact. In some embodiments, the molybdenum precursor, CO, and NH₃Is the only reactant used in the deposition cycle. In some embodiments, the thin film comprises MoCN or MoOCN. In some embodiments, CO and NH may be adjusted₃To deposit MoOCN.

In some embodiments, the molybdenum precursor is formed by contacting the substrate surface with a first reactant comprising a molybdenum precursor, a second reactant comprising a first reducing agent, a second reactant comprising a second reducing agent such as H₂And a nitrogen-containing reactant such as NH₃Is used to deposit a material comprising molybdenum, carbon, and nitrogen on the substrate in the reaction space. In some embodiments, the deposition process includes a deposition cycle in which the substrate is contacted with a first reactant comprising a vapor phase molybdenum precursor, a second reactant comprising carbon, such as CO, comprising H₂And a third reactant comprising nitrogen such as NH₃Alternately and sequentially. In some embodiments, the substrate is in simultaneous contact with at least two of the second, third, and fourth reactants. In some embodiments, the substrate is contacted with the second and third reactants simultaneously. In some embodimentsThe substrate is contacted with the third and fourth reactants simultaneously. In some embodiments, the substrate is contacted with the second and fourth reactants simultaneously. In some embodiments, the substrate is contacted with the second, third, and fourth reactants simultaneously. The deposition cycle may be repeated two or more times to deposit a film of a desired thickness.

Although referred to as a first reactant, a second reactant, a third reactant, and a fourth reactant, they need not be in contact with the substrate in that order during a deposition cycle. In some embodiments, the reactants are contacted with the substrate in the order of the first reactant, the second reactant, the third reactant, and the fourth reactant. In some embodiments, the substrate is contacted with one or both of the second, third and/or fourth reactants prior to contacting with the first reactant. In some embodiments, the substrate is sequentially contacted with a first reactant comprising a molybdenum precursor, and then with a second, third, and fourth reactant.

In some embodiments, the substrate is alternated and sequenced with a composition comprising a vapor phase molybdenum precursor, CO, H₂And NH₃Is contacted with the first reactant. In some embodiments, the substrate is CO, H₂And/or NH₃While in contact. In some embodiments, the substrate is alternated and sequentially with a gas phase comprising molybdenum precursor, CO, H₂And NH₃Is contacted with the first reactant. In some embodiments, the substrate is contacted with a first reactant comprising a molybdenum precursor, and then with CO, H, respectively₂And NH₃Then simultaneously with CO and H₂And NH₃Are contacted.

In some embodiments, the substrate is sequentially contacted with a first reactant comprising a molybdenum precursor, a second reactant, and then simultaneously contacted with a third and a fourth reactant. For example, the substrate may be sequentially contacted with a first reactant comprising a molybdenum precursor and CO, followed by H₂And NH₃While in contact. In some embodiments, the substrate is first contacted with a first reactant comprising a molybdenum precursor, and then subsequently contacted with a second, third, and fourth reactant, e.g., CO, H₂And NH₃While in contact. In some embodiments, a molybdenum precursor is includedA first reactant, a second reactant comprising carbon, such as CO, a reducing agent, such as H₂And a nitrogen-containing reactant such as NH₃Is the only reactant used in the deposition cycle. In some embodiments, molybdenum precursor, CO, H₂And NH₃Is the only reactant used in the 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.

In some embodiments, the molybdenum precursor comprises a molybdenum halide. In some embodiments, the molybdenum precursor comprises molybdenum oxyhalide. For example, in some embodiments, the molybdenum precursor may comprise MoO₂Cl₂、MoCl₅、MoOCl₄、MoBr₂Or MoI₃At least one of (1). In some embodiments, the molybdenum precursor may be made of MoO₂Cl₂、MoCl₅、MoOCl₄、MoBr₂Or MoI₃At least one of (1).

In some embodiments, Mo, MoOC, or MoOCN is deposited using molybdenum oxyhalide in a deposition process. For example, in some embodiments, Mo films are deposited by a deposition cycle in which the substrate and the coating comprise MoO₂Cl₂Or MoOCl₄A first reactant comprising a carbon such as CO, a second reactant comprising a reducing agent such as H₂A third reactant of (1). In some embodiments, the second reactant includes a reducing agent, and the reducing agent in the first and second reactants is different. In some embodiments, the reducing agents may be the same.

In some embodiments, the deposition process is an Atomic Layer Deposition (ALD) process. In some embodiments, a conformal thin film comprising molybdenum and carbon is deposited on, for example, a three-dimensional structure on a substrate. In vapor deposition techniques, ALD has the advantage of generally providing high conformality at low temperatures.

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 generally avoided by feeding the precursors alternately and sequentially into the reaction chamber. The gas phase reactants are separated from each other in the reaction chamber, for example by removing excess reactants and/or reactant byproducts from the reaction chamber between reactant pulses.

As described above, the substrate is typically heated to a suitable growth temperature before the deposition of the film begins. In short, the substrate is heated to a suitable deposition temperature, typically under reduced pressure. The preferred deposition temperature may vary depending on a number of factors such as, but not limited to, reactant precursors, pressure, flow rates, arrangement of the reactors, and substrate composition including the nature of the material to be deposited. The deposition temperature is typically kept below the thermal decomposition temperature of the reactants, but high enough to avoid condensation of the reactants and to provide activation energy for the desired surface reactions. Of course, for any given ALD reaction, the appropriate temperature window will depend on the surface termination and the reactant species involved. Here, the temperature varies depending on the precursor used, and is typically at or below about 700 ℃. In some embodiments, the deposition temperature is typically at or above about 100 ℃ and at or below about 700 ℃. In some embodiments, the deposition temperature is between about 200 ℃ to about 700 ℃, and in some embodiments, the deposition temperature is between about 300 ℃ to about 500 ℃. In some embodiments, the deposition temperature is less than about 500 ℃, less than about 400 ℃, or less than about 300 ℃. In some cases, the deposition temperature may be greater than about 200 ℃, greater than about 150 ℃, or greater than about 100 ℃. In some embodiments, a lower deposition temperature may be achieved, for example, if additional reactants or reducing agents are used in the process, such as reactants or reducing agents that contain hydrogen.

During a deposition cycle, the substrate surface is contacted with a first reactant comprising a vapor phase molybdenum precursor (also referred to as a molybdenum precursor). In some embodiments, pulses of a vapor phase molybdenum precursor are provided to a reaction space containing a substrate (e.g., in time-separated ALD). In some embodiments, the substrate is moved to a reaction space containing a vapor phase molybdenum precursor (e.g., in a spatially separated ALD, also referred to as a spatial ALD). The conditions may be selected such that no more than about a monolayer of the molybdenum precursor or species thereof is adsorbed on the first surface of the substrate. The conditions may be selected such that the precursor adsorbs in a self-limiting manner. The skilled person can easily determine the appropriate contact time on a case-by-case basis. Excess first reactant and reaction by-products, if present, are removed from the substrate surface, such as by purging with an inert gas or by removing the substrate from the presence of the first reactant.

The molybdenum precursor and the additional reactant are typically kept separate and in contact with the substrate, respectively. In particular, the molybdenum precursor is typically provided separately from the other reactants. However, as described herein, in some embodiments, two or more additional reactants may be provided together. Furthermore, in some arrangements, such as hybrid CVD/ALD or cyclic CVD, the process may allow different mutually reactive reactants to overlap on the substrate, so that more than one monolayer may be produced per cycle. The vapor phase precursors and/or vapor phase byproducts are removed from the substrate surface, such as by evacuating the chamber with a vacuum pump and/or by purging (e.g., replacing the gas within the reactor with an inert gas such as argon or nitrogen). The supply of precursors or reactants to the substrate surface is typically stopped during removal and may be diverted to a different chamber or vacuum pump during removal. 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 if desired, such as step coverage that requires high conformality on very high aspect ratio structures or other structures having complex topography.

The substrate surface is contacted with a gas phase second reactant. In some embodiments, the second reactant comprises a first reducing agent. 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 H₂. In some embodiments, the second reactant comprises CO, H₂And NH₃. In some embodiments, a pulse of a second reactant is provided to a reaction space containing a substrate. In some embodiments, the substrate is moved to a reaction space containing a gas phase second reactant. Excess second reactant and gaseous by-products of the surface reaction, if any, are removed from the substrate surface. In some embodiments, the deposition cycle includes alternating and sequentially cycling the linerThe base is contacted with a molybdenum precursor and a second reactant. In some embodiments, one or more additional reactants are used.

In some embodiments, after removing the second reactant and the gaseous by-product, in some embodiments, the surface of the substrate is contacted with a third gas-phase reactant or precursor. In some embodiments, the third gas phase reactant comprises a second reducing agent. In some embodiments, the second reductant is different from the first reductant. In some embodiments, the second reducing agent is the same as the first reducing agent. In some embodiments, the third gas phase reactant comprises hydrogen. In some embodiments, the third gas phase reactant comprises H₂. In some embodiments, the third gas phase reactant comprises NH₃. In some embodiments, the third gas phase reactant comprises NH₃And H₂. In some embodiments, a pulse of a third reactant is provided to a reaction space containing the substrate. In some embodiments, the substrate is moved to a reaction space containing a gas phase third reactant. Excess third reactant and gaseous by-products of the surface reaction, if any, are removed from the substrate surface.

In some embodiments, the second and third reactants may be provided simultaneously or in overlapping pulses. For example, in some embodiments, the second reactant comprises CO and the second reactant comprises H₂Is provided simultaneously or in overlapping pulses.

In some embodiments, the substrate may be contacted with a fourth vapor phase reactant. In some embodiments, the fourth gas-phase reactant includes a third reductant. In some embodiments, the fourth gas phase reactant comprises H₂And/or NH₃One or two of them. In some embodiments, the third gas phase reactant is H₂Or NH₃The fourth gas-phase reactant is H₂And NH₃The other of them. For example, in some embodiments, the third gas phase reactant comprises H₂The fourth gas phase reactant comprises NH₃. In some embodiments, a pulse of a fourth reactant is provided to a reaction space containing the substrate. In some embodiments, the substrate is moved to a reaction space containing a gas phase fourth reactant. For treatingThe amount of the fourth reactant and gaseous by-products of the surface reaction, if any, are removed from the substrate surface.

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, H is included₂And a third reactant comprising NH₃Is provided simultaneously or in overlapping pulses. In some embodiments, the substrate is contacted with the first reactant comprising the molybdenum precursor alone, even though it is contacted with two or more additional reactants simultaneously.

Although referred to as first, second, third, and fourth reactants, the reactants may be provided in a different order. In some embodiments, the molybdenum precursor is provided before any other reactants. In some embodiments, the molybdenum precursor is provided after the 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.

The contacting and removing are repeated until a thin film of a desired thickness is formed on the substrate, leaving no more than about one molecular monolayer per cycle in an ALD or ALD-type process, or one or more molecular monolayers in a hybrid CVD/ALD or cyclic CVD process.

Each reactant is introduced or pulsed into the chamber in the form of a gas phase pulse and contacts the substrate surface. In some embodiments, the substrate surface comprises a three-dimensional structure. In some embodiments, the conditions are selected such that no more than about one monolayer of each precursor adsorbs in a self-limiting manner on the substrate surface.

Excess precursor or reactant and reaction byproducts (if any) may be removed from and/or from the vicinity of the substrate and substrate surface between pulses of each precursor or reactant. In some embodiments, the reactants and reaction byproducts (if any) may be removed by purging. For example, purging may be accomplished with a pulse of an inert gas such as nitrogen or argon.

In some embodiments, excess precursor (or reactant and/or reaction by-product, etc.) is removed from the substrate surface or from a region of the substrate by physically moving the substrate from a location containing the precursor, reactant and/or reaction by-product.

The precursors and reactants used in the process can be solid, liquid or gaseous materials under standard conditions (room temperature and atmospheric pressure) provided they are in the gas phase before being introduced into the reaction chamber and contacted with the substrate surface.

The steps of contacting the substrate with each precursor and reactant, such as by pulsing, are repeated and excess precursor or reactant and reaction byproducts are removed until a thin film of desired thickness is formed on the substrate, typically leaving no more than about one molecular monolayer per complete cycle.

"pulsing" the vaporized reactant onto the substrate means that vapor is introduced into the chamber for a limited period of time, exposing the substrate to the reactant. Typically, the pulse time is from about 0.05 seconds to about 60 seconds or even longer. In some embodiments, the first reactant comprising a molybdenum precursor is pulsed for about 0.05 to about 10 seconds. In some embodiments, other reactants, such as reactants comprising 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 be determined according to the particular reaction conditions, including the type of substrate and its surface area.

By way of example, for a 300mm 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 seconds to about 60 seconds. However, in some cases, the pulse time may be several minutes. Also, the skilled person can easily determine the optimal pulse time on a case-by-case basis.

The mass flow of reactants can be determined by the skilled person. In some embodiments, for example for deposition on a 300mm wafer, the flow rate of the reactant is preferably between about 5sccm to about 1000sccm, about 10sccm to about 800sccm, or about 50sccm to about 500 sccm.

The pressure in the reaction chamber is typically about 1 to 70 torr or about 2 to 40 torr. However, in some cases, the pressure will be above or below this range, which can be readily determined by the skilled person based on a number of parameters, such as the particular reactor, process and precursor used.

As mentioned above, each pulse or phase of each cycle is preferably self-limiting. Excess reactant is supplied in each stage to saturate the sensitive structure surface. Surface saturation ensures that the reactants occupy all available reaction sites (e.g. limited by physical dimensions or "steric hindrance") thereby ensuring excellent step coverage. In some arrangements, the degree of self-limiting behavior can be adjusted by, for example, allowing some overlap of the reactant pulses to trade off deposition rate (by allowing some CVD-type reactions) and conformality. Ideal ALD conditions with good separation of reactants in time and space provide near perfect self-limiting behavior, providing maximum conformality, but steric hindrance results in less than one molecular layer per cycle. The limited CVD reaction mixed with the self-limiting ALD reaction can increase the deposition rate.

In some embodiments, the reaction space may be in a single wafer ALD reactor or a batch ALD reactor, where deposition on multiple substrates occurs simultaneously. In some embodiments, a substrate desired to be deposited, such as a semiconductor workpiece, is loaded into the reactor. The reactor may be part of a cluster tool in which various different processes in the formation of integrated circuits are performed. In some embodiments, a flow-type reactor is used. In some embodiments, a single wafer ALD reactor capable of high volume manufacturing is used. In other embodiments, a batch reactor comprising a plurality of substrates is used.

Examples of suitable reactors that may be used include commercially available ALD equipment. In addition to ALD reactors, many other kinds of reactors capable of ALD growth of thin films may be used, including CVD reactors equipped with appropriate equipment and means for pulsing the precursors. In some embodiments, a flow-type ALD reactor is used. Preferably, the reactants are kept separate until the reaction chamber is reached, so that the shared lines for the precursors are minimized. However, other arrangements are possible.

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

The deposition process described herein may optionally be carried out in a reactor or reaction space connected to a cluster tool. In a cluster tool, because each reaction space is dedicated to one type of process, the temperature of the reaction space in each module can be kept constant, which can improve throughput compared to reactors that heat the substrate to the process temperature before each run.

In some embodiments, Mo, MoC, Mo is deposited by a deposition cycle₂C. A MoOC, MoOCN or MoCN thin film, the deposition cycle comprising alternately and sequentially contacting the substrate with a first reactant comprising a molybdenum precursor, a second reactant comprising carbon and oxygen (such as a second reactant comprising carbon monoxide (CO)), and hydrogen (such as H)₂) Or ammonia (NH)₃) Is contacted with at least one third reactant. 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 comprise MoO₂Cl₂、MoCl₅、MoOCl₄、MoBr₂Or MoI₃At least one of (1). In some embodiments, the first reactant may be made of MoO₂Cl₂、MoCl₅、MoOCl₄、MoBr₂Or MoI₃At least one of (1). In some embodiments for depositing Mo, the first reactant may be a molybdenum oxyhalide, for example a molybdenum oxychloride, such as MoO₂Cl₂Or MoOCl₄。

In the deposition of Mo, MoC, MoOC or Mo₂In some embodiments of C, hydrogen may be used as a reactant comprising hydrogen. In some embodiments, such as MoOCN, MoCN, where nitrogen needs to be introduced into the deposition material, a reactant comprising ammonia may be used as a reactant comprising hydrogen.

In some embodiments, a molybdenum precursor comprising oxygen is used, and a reactant comprising carbon and oxide can remove oxygen from the molybdenum precursor and contribute carbon to the growing MoC, MoOC, Mo₂C or MoCN film. The hydrogen reactant can remove halogenThe halide ligand, and in the case of ammonia, may remove the halide and contribute nitrogen to the growing MoCN film. The deposition cycle is repeated to deposit a film of the desired thickness.

In some embodiments, one or more reactants (CO, H) may be provided after the molybdenum precursor₂And NH₃). In some embodiments, the molybdenum precursor is first contacted with the substrate, followed by sequentially contacting 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 sequentially contacting with at least one reactant, such as hydrogen or ammonia, and a reactant comprising carbon and an oxide.

For example, in some embodiments, the film deposition cycle includes three phases. In a first stage, the substrate is contacted with only a first reactant comprising a molybdenum precursor. In a second stage, a substrate comprising a molybdenum precursor species is contacted with a second reactant comprising CO. In a third stage, 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 stages are combined such that in the first stage the substrate is in contact with the molybdenum precursor only, and in the second stage the substrate is in contact with CO, H₂And/or NH₃And (4) contacting.

In some embodiments, the first reactant is provided after the at least one other reactant. In some embodiments, after the first reactant, the substrate is contacted with at least one of a carbon monoxide reactant, a hydrogen reactant, or an ammonia reactant. For example, in some embodiments, a carbon monoxide reactant is contacted with the substrate, then a first reactant is contacted with the substrate, and at least one of a hydrogen reactant or an ammonia reactant may be contacted with the substrate. In some embodiments, at least one of the hydrogen reactant or the ammonia reactant may be contacted with the substrate, then the first reactant is contacted with the substrate, and the carbon monoxide reactant is contacted with the substrate.

Repeating the deposition cycle to deposit a film comprising molybdenum and carbon, such as MoC, MoOC, Mo of a desired thickness₂C. MoOCN or MoCN thin films.

In some embodiments, MoC, MoOC, or Mo₂C is deposited by a deposition cycle comprising alternately and sequentially contacting the substrate with a first reactant comprising a molybdenum precursor, a second reactant comprising carbon monoxide and a first reactant comprising H₂Is contacted with the third reactant. In some embodiments, the second reactant comprising carbon monoxide and the second reactant comprising H₂Is provided together with the third reactant. That is, in some embodiments, the substrate may be separately contacted with a first reactant comprising a molybdenum precursor, and with a second reactant comprising carbon monoxide and a second reactant comprising H₂Is contacted simultaneously.

In some embodiments, the MoOCN or MoCN thin film is deposited by a deposition cycle comprising alternately and sequentially contacting the 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 separately contacted with a first reactant comprising a molybdenum precursor, and simultaneously contacted with a second reactant comprising carbon monoxide and a third reactant comprising ammonia. In some embodiments, including H in one or more deposition cycles₂Of (4) an additional reactant. Thus, in some embodiments, a MoOCN or MoCN thin film is deposited using at least one deposition cycle comprising alternately and sequentially depositing a substrate with a first reactant comprising a molybdenum precursor, a second reactant comprising carbon monoxide, a third reactant comprising ammonia, and a first reactant comprising H₂Is contacted with the fourth reactant. In some embodiments, a composition comprising carbon monoxide, ammonia, and H may be provided together₂Two or more reactants of (a). For example, the substrate may be alternately and sequentially reacted with a first reactant comprising a molybdenum precursor, a second reactant comprising CO, and a first reactant comprising H₂And NH₃Is contacted with the reactants. 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 molybdenum oxyhalide and the ratio of the additional reactants is adjusted to deposit the desired material.

In some embodiments, the order of providing the reactants may vary.For example, in some embodiments, each reactant (CO, H) may be provided after the first reactant comprising a molybdenum precursor in a deposition cycle₂And/or NH₃). For example, one of the carbon monoxide reactant, the hydrogen reactant, and/or the ammonia reactant contacts the substrate after the molybdenum precursor and reacts with the adsorbed species of the molybdenum precursor. In some embodiments, one or more reactants may be provided prior to the molybdenum precursor during a deposition cycle. In this case, one or more reactants provided prior to the molybdenum precursor will react with the adsorbed molybdenum species in a subsequent deposition cycle. In some embodiments, the order of the additional reactants is not critical. In some embodiments, the carbon monoxide reactant is in H₂Or NH₃The reactants are provided prior. In other embodiments, H is provided before the carbon monoxide reactant₂Or NH₃And (3) reacting the raw materials.

In some embodiments, at least one deposition cycle may include another processing phase in which the substrates are respectively contacted with a gas phase reactant comprising oxygen, such as H₂O、O₃、H₂O₂、N₂O、NO₂Or NO. This may be referred to as an oxidation stage. In some embodiments, the oxidation stage may be performed after the substrate is contacted with the first reactant comprising a molybdenum precursor. In some embodiments, the oxidation phase may be performed last in the deposition cycle. For example, a deposition cycle can include contacting a substrate with a first reactant comprising a molybdenum precursor, contacting a substrate with a second reactant comprising CO, contacting a substrate with a second reactant comprising H₂And/or NH₃And contacting the substrate with a reactant comprising oxygen. In some embodiments, the oxidation phase is included in one deposition cycle. In some embodiments, the oxidation phase is included in a plurality of deposition cycles or in each deposition cycle. In some embodiments, an oxidation phase is included at intervals during the deposition process.

Fig. 2 is a flow diagram illustrating a deposition process 200 for depositing a thin film comprising molybdenum, according to some embodiments. Referring to fig. 2, a thin film comprising molybdenum is deposited on a substrate in a reaction space by a deposition process 200. The deposition process 200 includesAt least one deposition cycle includes contacting the substrate surface with a first reactant comprising a vapor phase molybdenum precursor at block 210, removing excess molybdenum precursor and reaction byproducts, if any, from the surface at block 220, contacting the substrate surface with a vapor phase second reactant at block 230, removing any excess second reactant and reaction byproducts, if any, from the substrate surface at block 240, contacting the substrate surface with a vapor phase third reactant at block 250, and removing any excess third reactant and reaction byproducts, if any, from the substrate surface at block 260. The contacting and removing step 210 and 260 may optionally be repeated at block 270 to form a thin film comprising molybdenum of a desired thickness. For example, molybdenum, MoC, Mo may be deposited₂C. MoOC, MoOCN or MoCN films.

In some embodiments, the molybdenum precursor may include a molybdenum halide, as described above. In some embodiments, the molybdenum precursor may comprise molybdenum oxyhalide. For example, the molybdenum precursor may comprise MoO₂Cl₂、MoCl₅、MoOCl₄、MoBr₂Or MoI₃At least one of (1). In some embodiments, the precursor may be made of MoO₂Cl₂、MoCl₅、MoOCl₄、MoBr₂Or MoI₃At least one of (1).

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 be comprised of carbon monoxide (CO).

In some embodiments, the third reactant may include a nitrogen reactant, such as ammonia (NH)₃). In some embodiments, the third reactant may be made of ammonia (NH)₃) And (4) forming.

In some embodiments, the third reactant may include a second reducing agent. In some embodiments, the third reactant may include hydrogen, such as H₂. In some embodiments, the third reactant may be comprised of hydrogen, such as H₂。

In some embodiments, Mo, MoC, MoOC, or Mo may be deposited by the process shown in FIG. 2₂And C, film forming. In some embodiments, the molybdenum precursor comprises a molybdenum halide, such as MoOCl₄Or MoO₂Cl₂The second reactant comprises CO and the third reactant comprises H₂. In some embodiments, the second reactant comprises H₂And the third reactant comprises CO. Can control MoC, MoOC or Mo₂C, 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 or third reactant may be omitted to adjust the ratio of time that the substrate is in contact with the second and third reactants throughout the deposition process.

In some embodiments, the only reactants used in the deposition cycle are the molybdenum precursor, CO, and H₂。

In some embodiments, a MoCN film may be deposited. In some embodiments, the molybdenum precursor comprises a molybdenum halide, such as MoOCl₄Or MoO₂Cl₂The second reactant comprises CO and the third reactant comprises NH₃. In some embodiments, the second reactant comprises NH₃And the third reactant comprises CO.

In some embodiments, the only reactants used in the deposition cycle are the molybdenum precursor, CO, and NH₃。

In some embodiments, the cyclical deposition process 200 described above may be an ALD-type process. In some embodiments, the cyclical deposition process 200 can be an ALD process. In some embodiments, the cyclical process 200 described above may be a hybrid ALD/CVD or cyclical CVD process.

Although the deposition cycle is illustrated as beginning with the substrate surface being contacted with the first reactant comprising the vapor phase molybdenum precursor 210, in other embodiments, the deposition cycle may begin with the substrate surface being contacted with the second reactant 230 or the third reactant 250.

In some embodiments, removing the precursor or reactant and any excess reaction by-product at blocks 220, 240, 260 may include purging the reaction space or chamber. Purging the reaction chamber may include using a purge gas and/or applying a vacuum to the reaction space. Where a purge gas is used, the purge gas may flow continuously, or may flow through the reaction space only after the flow of reactant gas has stopped and before the next reactant gas begins to flow through the reaction space. It is also possible to continuously flow a purge or non-reactive gas through the reaction chamber so that the non-reactive gas acts as a carrier gas for the various reactive species. Thus, in some embodiments, a gas, such as nitrogen, is continuously flowed through the reaction space while the molybdenum precursor and the reactant are pulsed into the reaction chamber as needed. Because the carrier gas is continuously flowing, excess reactant or reaction by-products can be removed simply by stopping the flow of reactant gas into the reaction space.

In some embodiments, removing the precursor or reactant and any excess reaction by-products at blocks 220, 240, 260 may include moving the substrate from a first reaction chamber to a different second reaction chamber. In some embodiments, removing the precursor or reactant and any excess reaction by-products at blocks 220, 240, 260 may include moving the substrate from a first reaction chamber to a different second reaction chamber under vacuum.

In some embodiments, the deposited film comprising molybdenum may be subjected to a treatment process after deposition. In some embodiments, the treatment process can, for example, enhance the conductivity or continuity of the deposited film comprising molybdenum. In some embodiments, the treatment process may include, for example, an annealing process.

Fig. 3 is a flow diagram illustrating a deposition process 300 for depositing a thin film comprising molybdenum, according to some embodiments. The deposition process 300 is similar to the deposition process 200 except that the second reactant and the third reactant are simultaneously in contact with the substrate, such as by co-flowing together into the reaction space. The deposition process 300 includes at least one deposition cycle including contacting the substrate surface with a first reactant comprising a vapor phase molybdenum precursor at block 310, removing any excess molybdenum precursor and reaction byproducts (if any) from the surface at block 320, simultaneously contacting the substrate surface with a vapor phase second reactant and a vapor phase third reactant at block 330, and removing excess second and third reactants and reaction byproducts (if any) from the substrate surface at block 340. The deposition cycle including the contacting and removing steps 310-340 may be repeated at block 350 to formInto a thin film comprising molybdenum of a desired thickness. For example, Mo, MoC, Mo may be deposited₂C. MoOC, MoOCN or MoCN films.

As shown in fig. 3, in some embodiments, the molybdenum precursor comprises molybdenum oxychloride. However, other molybdenum precursors may also be used. In some embodiments, the molybdenum precursor may include a molybdenum halide, such as molybdenum oxyhalide. For example, the molybdenum precursor may comprise MoO₂Cl₂、MoCl₅、MoOCl₄、MoBr₂Or MoI₃At least one of (1). For example, the precursor may be made of MoO₂Cl₂、MoCl₅、MoOCl₄、MoBr₂Or MoI₃At least one of (1).

In some embodiments, the second reactant may include a first reducing agent. In some embodiments, the second reactant comprises 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)₃). In some embodiments, the third reactant may include a second reducing agent. In some embodiments, the third reactant may include hydrogen, such as H₂. In some embodiments, the second reactant may include CO and the third reactant may include NH₃. In some embodiments, the second reactant may include CO and the third reactant may include H₂. In some embodiments, the second reactant may include CO and the third reactant may include NH₃And H₂。

Thus, in some embodiments, the second and third reactants may include CO and H₂And they may flow together into the reaction space. In some embodiments, the second and third reactants may include CO and NH₃And they may flow together into the reaction space. In some embodiments, a carrier gas may be supplied to the molybdenum precursor and/or one or more reactants. In some embodiments, the CO-flow of the second reactant and the third reactant may be made of CO and H₂And (4) forming. In some embodiments, the CO-flow of the second reactant and the third reactant may be made of CO and NH₃And (4) forming.

In some embodiments, MoC or Mo may be deposited₂And C, film forming. In some embodiments, the molybdenum precursor may comprise MoOCl₄Or MoO₂Cl₂And the CO-stream of the second reactant and the third reactant may include CO and H₂. MoC, MoOC or Mo₂The deposition of C can be controlled by adjusting the ratio of the second reactant and the third reactant.

In some embodiments, a MoOCN or MoCN film may be deposited. In some embodiments, the molybdenum precursor comprises MoOCl₄Or MoO₂Cl₂And the CO-stream of the second reactant and the third reactant may comprise CO and NH₃. In some embodiments, the third reactant comprises NH₃And H₂So that CO, NH₃And H₂Flow together.

Fig. 4 is a flow diagram illustrating a deposition process 400 for depositing a thin film comprising molybdenum, according to some embodiments. The deposition process 400 is similar to the deposition process 200 except that an additional fourth reactant is further used. The deposition process 400 includes at least one deposition cycle that includes contacting the substrate surface with a first reactant comprising a vapor phase molybdenum precursor at block 410, removing any excess molybdenum precursor and reaction byproducts (if any) from the surface at block 420, contacting the substrate surface with a vapor phase second reactant at block 430, removing any excess second reactant and reaction byproducts (if any) from the substrate surface at block 440, contacting the substrate surface with a vapor phase third reactant at block 450, removing any excess third reactant and reaction byproducts (if any) from the substrate surface at block 460, contacting the substrate surface with a vapor phase fourth reactant at block 470, and removing any excess fourth reactant and reaction byproducts (if any) from the substrate surface 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, a MoOCN or MoCN thin film may be deposited.

In some embodiments, the molybdenum precursor may include a molybdenum halide or a molybdenum oxyhalide. For example, the molybdenum precursor may comprise MoO₂Cl₂、MoCl₅、MoOCl₄、MoBr₂Or MoI₃At least one of (1).

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), and the third reactant may include nitrogen, such as ammonia (NH)₃) The fourth reactant may include a second reducing agent, such as hydrogen (H)₂). In some embodiments, the second reactant may be comprised of carbon monoxide (CO) and the third reactant may be comprised of ammonia (NH)₃) The fourth reactant may be hydrogen (H)₂) And (4) forming.

In some embodiments, the second reactant may include carbon and oxygen, such as carbon monoxide (CO), and the third reactant may include hydrogen (H)₂) The fourth reactant may include nitrogen, such as ammonia (NH)₃). In some embodiments, the second reactant may be composed of carbon and oxygen, such as carbon monoxide (CO), and the third reactant may be hydrogen (H)₂) The fourth reactant may be ammonia (NH)₃) And (4) forming.

In some embodiments, the second reactant may include hydrogen (H)₂) The third reactant may include carbon and oxygen, such as carbon monoxide (CO), and the fourth reactant may include nitrogen, such as ammonia (NH)₃). In some embodiments, the second reactant may be hydrogen (H)₂) The third reactant may be comprised of carbon and oxygen, such as carbon monoxide (CO), and the fourth reactant may be comprised of nitrogen, such as ammonia (NH)₃)。

In some embodiments, the second reactant may include hydrogen (H)₂) The third reactant may include nitrogen, such as ammonia (NH)₃) The fourth reactant may include carbon and oxygen, such as carbon monoxide (CO). In some embodiments, the second reactant may be hydrogen (H)₂) The third reactant may be comprised of nitrogen, such as ammonia (NH)₃) The fourth reactant may be comprised of carbon and oxygen, such as carbon monoxide (CO).

In some embodiments, the second reactant may include nitrogen, such as ammonia (NH)₃) The third reactant may beIncluding carbon and oxygen, such as carbon monoxide (CO), and the fourth reactant may include hydrogen (H)₂). In some embodiments, the second reactant may be comprised of nitrogen, such as ammonia (NH)₃) The third reactant may be comprised of carbon and oxygen, such as carbon monoxide (CO), and the fourth reactant may be comprised of hydrogen (H)₂) And (4) forming.

In some embodiments, the second reactant may include nitrogen, such as ammonia (NH)₃) The third reactant may include hydrogen (H)₂) The fourth reactant may include carbon and oxygen, such as carbon monoxide (CO). In some embodiments, the second reactant may be comprised of nitrogen, such as ammonia (NH)₃) The third reactant may be hydrogen (H)₂) The fourth reactant may be comprised of carbon and oxygen, such as carbon monoxide (CO).

In some embodiments, H₂Can be reacted with NH in any deposition process₃Co-flow, e.g., steps 200, 300 or 400 in fig. 2, 3 and 4, respectively.

In some embodiments, an oxidation process may be performed, for example, prior to block 230. For example, in an oxidation process, H₂O、O₃、H₂O₂、N₂O、NO₂Or NO may be in contact with the substrate. For example, containing MoOCl₄Can be dissociated in an oxidation step to form MoO₂And release HCl gas and O₂. After the oxidation process, the second and/or third reactants, i.e., CO and H, may be used₂And/or NH₃Adding MoO₂Reducing to form a Mo film. In some embodiments, the oxidation process may include H₂O and H₂To the flow of the liquid.

Film characteristics

The films deposited according to some embodiments described herein may be continuous films comprising molybdenum. In some embodiments, the molybdenum-containing film may be continuous at the following thicknesses: less than about 100nm, less than about 60nm, less than about 50nm, less than about 40nm, less than about 30nm, less than about 25nm, or less than about 20nm, or less than about 15nm, or less than about 10nm, or less than about 5nm or less. The continuity referred to may be physical continuity or electrical continuity. In some embodiments, the thickness to which the film may be physically continuous may be different than the thickness to which the film is electrically continuous, and the thickness to which the film may be electrically continuous may be different than the thickness to which the film is physically continuous.

While in some embodiments, films comprising molybdenum deposited according to some embodiments described herein may be continuous, in some embodiments, it may be desirable to form a discontinuous film comprising molybdenum, or a film comprising individual islands or nanoparticles comprising molybdenum. In some embodiments, a deposited film comprising molybdenum can comprise nanoparticles comprising molybdenum that are substantially physically or electrically discontinuous with one another. In some embodiments, the deposited film comprising molybdenum may comprise individual nanoparticles or individual islands comprising molybdenum.

In some embodiments, a thin film comprising molybdenum deposited according to some embodiments described herein may have a resistivity of less than about 20 μ Ω cm at a thickness of less than about 100 nm. In some embodiments, a thin film comprising molybdenum deposited according to some embodiments described herein may have a resistivity of less than about 20 μ Ω cm at the following thicknesses: less than about 60nm, less than about 50nm, less than about 40nm, less than about 30nm, less than about 25nm, or less than about 20nm or less. In some embodiments, a thin film comprising molybdenum deposited according to some embodiments described herein may have a resistivity of less than about 15 μ Ω cm at the following thicknesses: less than about 60nm, less than about 50nm, less than about 40nm, less than about 30nm, less than about 25nm, or less than about 20nm or less. In some embodiments, a thin film comprising molybdenum deposited according to some embodiments described herein may have a resistivity of less than about 10 μ Ω cm at the following thicknesses: less than about 60nm, less than about 50nm, less than about 40nm, less than about 30nm, less than about 25nm, or less than about 20nm or less. In some embodiments, a thin film comprising molybdenum deposited according to some embodiments described herein may have a resistivity of less than about 200 μ Ω cm at the following thicknesses: less than about 30nm, less than about 20nm, less than about 15nm, less than about 10nm, less than about 8nm, or less than about 5nm or less.

In some embodiments, a thin film comprising molybdenum deposited according to some embodiments described herein may have the following resistivity at a thickness of less than about 100 nm: less than about 200 μ Ω cm, less than about 100 μ Ω cm, less than about 50 μ Ω cm, less than about 30 μ Ω cm, less than about 20 μ Ω cm, less than about 18 μ Ω cm, less than about 15 μ Ω cm, less than about 12 μ Ω cm, less than about 10 μ Ω cm, less than about 8 μ Ω cm, or less than about 5 μ Ω cm or less. In some embodiments, a thin film comprising molybdenum deposited according to some embodiments described herein may have the following resistivity at a thickness of less than about 50 nm: less than about 20 μ Ω cm, less than about 18 μ Ω cm, less than about 15 μ Ω cm, less than about 12 μ Ω cm, less than about 10 μ Ω cm, less than about 8 μ Ω cm, or less than about 5 μ Ω cm or less.

In some embodiments, depositing MoC, Mo₂C. MoOC, MoOCN or MoCN films to a thickness of less than about 10nm, more preferably less than about 5nm, most preferably less than about 3 nm.

Atomic layer deposition allows conformal deposition of Mo, MoC, Mo₂C. MoOC, MoOCN or MoCN membranes. In some embodiments, Mo, MoC, Mo deposited on a three-dimensional structure by the process disclosed herein₂The C or MoCN film has a conformality of at least 90%, 95%, or more. In some embodiments, the film is about 100% conformal.

In some embodiments, Mo, MoC, Mo is formed in structures having high aspect ratios₂C. The MoOC, MoOCN, or MoCN film has a step coverage of greater than about 80%, more preferably greater than about 90%, and most preferably greater than about 95%. In some embodiments, the aspect ratio of the high aspect ratio structures is greater than about 3:1 when comparing the depth or height to width of the features. In some embodiments, the aspect ratio of the structure is greater than about 5:1, or even an aspect ratio of 10:1 or greater.

In some embodiments, molybdenum films such as Mo, MoC, Mo deposited by the processes disclosed herein are applied after deposition, such as by annealing, as desired for an application₂C. MoOC, MoOCN or MoCN membranes. In some embodiments, Mo, MoC, Mo₂C. The MoOC, MoOCN or MoCN film is annealed in an oxygen ambient. For example, the membrane may be in water or O at elevated temperature₂And (5) annealing. In some embodiments, no annealing step is performed.

In some embodiments, after depositing the molybdenum film, such as Mo, MoC, Mo₂C or MoCN deposition, another film is deposited. In some embodiments, the additional film may be directly on and in contact with the molybdenum film, such as directly on Mo, MoC, Mo₂C. On and in contact with the MoOC, MoOCN or MoCN layer.

While certain embodiments and examples have been discussed, it will be understood by those skilled in the art that the scope of the claims extends beyond the specifically disclosed embodiments to other alternative embodiments and/or uses and obvious modifications and equivalents thereof.