Pulsed delivery of reactive gases

Abstract

Provided herein are methods for delivering gas reactants to a processing chamber and its associated equipment.

Description

Technical Field

[0001] Incorporation by Reference As part of this application, a PCT application form is submitted simultaneously with this specification. For all purposes, each application for which this application claims the benefits or priority rights as described in the simultaneously submitted PCT application form is incorporated by reference in its entirety into this application.

Background Art

[0002] The challenge in semiconductor processing is to achieve process uniformity of the processed wafers over as wide a range as possible.

[0003] The background description provided herein is intended to present the context of the present disclosure as a whole. Within the scope described in this background section, aspects of the inventors' research currently described and aspects of the description that may not be eligible as prior art at the time of filing are not recognized as prior art that explicitly or implicitly confronts the present disclosure.

Summary of the Invention

[0004] One aspect of the present disclosure relates to a method including performing a suppression process on a substrate. The method includes introducing a co-flow pulse of a reactive suppression gas and a metal precursor gas into a chamber, each co-flow pulse including a pulse of the reactive suppression gas and a pulse of the metal precursor gas, and the pulse of the reactive suppression gas and the pulse of the metal precursor gas being offset and overlapping on the time axis. The pulse (also referred to as a dose) is measured from the time when the gas flows from the gas source. The suppression process suppresses the nucleation of the metal.

[0005]

[0006] ​In some embodiments, each pulse of the reactivity suppressing gas is separated from subsequent pulses of the reactivity suppressing gas by a purge, and each pulse of the metal precursor gas is separated from subsequent pulses of the metal precursor gas by a purge.

[0007] In some embodiments, the metal is one of tungsten (W), molybdenum (Mo), cobalt (Co), and ruthenium (Ru).

[0008] In some embodiments, the reactivity-suppressing gas is nitrogen-containing. In some embodiments, the reactivity-suppressing gas is ammonia (NH3) or hydrazine (N2H4).

[0009] In some embodiments, the method further includes calculating the deviation from the delay parameter. In some such embodiments, the deviation calculation includes optimizing uniformity within the wafer.

[0010] In some embodiments, the method further includes depositing a metal before and / or after a suppression treatment. The deposition operation may be carried out in the same chamber as the suppression treatment or in a different chamber. In some embodiments, the deposition operation is carried out in a first station of a multi-station chamber, and the suppression treatment is carried out in a second station. In some embodiments, deposition is carried out by atomic layer deposition (ALD) using a metal precursor and a reducing gas. Co-current pulses may or may not be included.

[0011] Another aspect of the present disclosure relates to a chamber having one or more stations, each station having a pedestal and a showerhead positioned on the pedestal and configured to be fluidly connected to a first gas source and a second gas source; and a controller comprising instructions to introduce a plurality of parallel pulses of a first gas and a second gas into the stations of the chamber, each parallel pulse comprising a pulse of the first gas and a pulse of the second gas, the first gas pulses and the second gas pulses overlapping with a time lag, each pulse of the first gas being separated from subsequent pulses of the first gas via a purge, and each pulse of the second gas being separated from subsequent pulses of the second gas via a purge. The pulses (also called doses) are measured from the point in time when the gas flows from the gas source.

[0012] In some embodiments, the controller further includes instructions for calculating deviations from one or more parameters. In some such embodiments, the controller further includes instructions for receiving one or more parameters.

[0013] In some such embodiments, one or more parameters include some or all of the following: the discriminability of the gas to be delayed, the length of the delay, and whether to shorten the pulse or shorten the purge.

[0014] In some embodiments, the controller further includes instructions to modify the pulse sequence of the first or second gas according to the calculated deviation.

[0015] Another aspect of the present disclosure relates to a method for introducing a plurality of parallel pulses of a first gas and a second gas into a processing chamber, each of which parallel pulses comprises a pulse of the first gas and a pulse of the second gas, the first gas pulses and the second gas pulses overlapping with a time lag, each pulse of the first gas being separated from subsequent pulses of the first gas via a purge, and each pulse of the second gas being separated from subsequent pulses of the second gas via a purge. The pulses (also called doses) are measured from the point in time when the gas flows from the gas source.

[0016] In some embodiments, the method further includes calculating a deviation from one or more parameters. In some such embodiments, the method includes receiving one or more parameters. In some embodiments, one or more parameters include some or all of the following: the identifiability of the gas to be delayed, the length of the deviation, and whether to shorten the pulse or purge.

[0017] In some such embodiments, the method further includes modifying the pulse sequence of the first or second gas in accordance with the calculated deviation.

[0018] Another aspect of the present disclosure relates to a tangible, machine-readable medium, which includes instructions for introducing a first gas, a second gas, and a plurality of parallel pulses into a processing chamber, each parallel pulse comprising a pulse of the first gas and a pulse of the second gas, wherein the pulses of the first gas and the pulses of the second gas overlap with a time lag, each pulse of the first gas is separated from subsequent pulses of the first gas via a purge, and each pulse of the second gas is separated from subsequent pulses of the second gas via a purge. The pulses (also called doses) are measured from the point in time when the gas flows from the gas source.

[0019] In some embodiments, the tangible machine-readable medium further includes instructions for calculating deviations from one or more parameters.

[0020] In some embodiments, the tangible machine-readable medium further includes instructions to receive one or more parameters from a user input. In some embodiments, the one or more parameters include some or all of the identity of the gas to be delayed, the length of the displacement, and whether to shorten the pulse or purge. In some embodiments, the tangible machine-readable medium further includes instructions to modify the sequence of pulses of the first gas or the second gas according to the calculated displacement.

[0021] These and other aspects of the present disclosure are described in detail below with reference to the drawings.

Brief Description of the Drawings

[0022] [Figure 1] FIG. showing an example of a deposition-suppression-deposition (DID) process for filling features that can be implemented according to various embodiments described herein.

[0023] [Figure 2] FIG. showing an exemplary timing sequence of a co-flow pulse without a phase shift and a co-flow shift with a phase shift.

[0024] [Figure 3] FIG. showing an exemplary timing sequence with a delay in B in two cycles of co-flow pulses of process gas A and process gas B.

[0025] [Figure 4] FIG. showing the flow of gases A and B over the wafer, corresponding to the timing sequence shown in FIG. 2.

[0026] [Figure 5] FIG. showing an example of transient simulation results of the mass fraction of NH₃ and the mass fraction of WF₆ and the position from the center of the wafer generated by simulation.

[0027] [Figure 6]This is a plot of nucleation delay at the wafer center and wafer edge against reactant delay in various NH3 / WF6 suppression processes.

[0028] [Figure 7] This is an example of a timing sequence diagram illustrating an exemplary cycle for depositing a tungsten nucleation layer using diborane.

[0029] [Figure 8] This is an example of a timing sequence diagram from Figure 7, modified to include delays.

[0030] [Figure 9a] This figure shows an example of a two-part plenum showerhead configured to supply two different types of gas to separate chambers.

[0031] [Figure 9b] This figure shows an example of a charging container connected to a showerhead.

[0032] [Figure 10] This is a schematic diagram of the gas flow, including the mass flow controller (MFC), charge container (CV), and outlet valve connected to the showerhead.

[0033] [Figure 11] This figure shows an apparatus that may be used according to a specific embodiment.

[0034] [Figure 12] This figure shows an example of a multi-station device that may be used in a particular embodiment. [Modes for carrying out the invention]

[0035] Examples of various embodiments are shown in the accompanying drawings and described in detail below. It will be understood that the discussion in this specification is not intended to limit itself to the specific embodiments described in the claims. On the contrary, it is intended to include alternatives, modifications, and equivalents in that they may fall within the spirit and scope of this disclosure and the accompanying claims. Many specific details are described below in order to allow for a full understanding of the disclosed subject matter. Various implementations of the subject matter may be carried out without some or all of these specific details. In other cases, known processing operations are not described in detail in order to avoid unnecessarily obscuring the subject matter described herein.

[0036] This specification provides a method and apparatus for supplying reactants to a semiconductor substrate. This method and apparatus may be used in processes that include the parallel flow of pulsed gases. Parallel flow of pulsed gases refers to gases supplied in a pulsed state to a chamber containing a substrate, such that the gases are simultaneously present in the chamber. The pulsed gases are supplied to the chambers separately but are not pre-mixed. An example of a process that may include the parallel flow of pulsed reactants is a deposition-suppression-deposition (DID) suppression operation. Note that while parallel flowing gases are sometimes described as reactants in this specification, they do not necessarily react during the processing.

[0037] Figure 1 shows an example of a DID process that may be carried out according to various embodiments described herein. First, 100 shows an unfilled feature 102 in the pre-filling stage. Feature 102 may be formed in one or more layers on a semiconductor substrate and optionally have one or more layers along the sidewalls and / or bottom of the feature. 110 shows feature 102 after the filler material has been initially deposited to form a layer of material 104 that fills feature 102. Examples of materials include tungsten, cobalt, molybdenum, and ruthenium, but the techniques described herein may be used to suppress any suitable material.

[0038] In 120, feature 102 shows the state after suppression treatment. Suppression treatment is a treatment that has the effect of suppressing the occurrence of subsequent deposition on the treated surface 106. Suppression may require various mechanisms depending on various factors such as the surface to be treated and the suppression chemical. In the methods described herein, suppression is a thermal (i.e., not plasma) treatment. In one example, tungsten nucleation and the subsequent tungsten deposition are suppressed by exposure to a nitrogen-containing chemical. This may involve exposure to ammonia vapor in an example of thermal treatment.

[0039] Examples of suppression mechanisms include chemical reactions between a suppressing species and a feature surface to form a thin layer of composite material such as tungsten nitride (WN) or tungsten carbide (WC). In some embodiments, suppression may involve surface effects such as adsorption that passivate the surface without forming a layer of composite material. It should be noted that the methods described herein do not rely on a detailed or complete understanding of the physical mechanisms causing suppression behavior.

[0040] The characteristics of suppression can be its depth and gradient. That is, because suppression can vary with depth, it may be greater at the opening of a feature than at the bottom, and may only extend partway through the feature. In the illustrated example, the suppression depth is approximately half the total depth of the feature. Furthermore, the suppression is stronger at the top of the feature, extending deep into the feature as shown by the dashed line.

[0041] Deposition is suppressed near the feature opening during Deposition 2, as shown in 130, so that the material preferentially deposits at the bottom of the feature and little to no deposits at the feature opening. This prevents the formation of voids and seams within the feature after filling. Thus, in Deposition 2, the material 104 may fill in a manner characterized by bottom-up filling rather than conformal filling as in Deposition 1. As deposition continues, the suppression effect may diminish, thereby potentially leading to unsuppressed deposition on lightly treated surfaces. This is shown in 130, where the treated surface 106 has less spread than before Deposition 2. In the example in Figure 1, as Deposition 2 progresses, the suppression eventually weakens across the entire surface, and the feature is completely filled with material 104, as shown in 140.

[0042] The DID process in Figure 1 shows that features are preferentially suppressed at the top, but in some embodiments, the entire feature may be suppressed. Such a process can be useful, for example, to prevent line curvature.

[0043] The suppression operation may include pulsed parallel flow of a suppression gas and a precursor gas. For example, in a DID process for tungsten loading, the suppression operation 120 may involve pulses of a process gas containing a reactive suppression gas such as ammonia (NH3) and a tungsten precursor such as (WF6). The suppression gas pulse is separated by an inert purge gas such as argon (Ar). The precursor pulse is also separated by an inert purge gas. When the process gas flows in parallel, the process gas is introduced into the chamber separately and simultaneously enters the gas phase within the chamber.

[0044] In the methods presented herein, the parallel flow of gases may be phase-shifted to improve uniformity and / or performance. Figure 2 shows an example of a timing sequence for parallel flow of pulses with or without phase shifting. Phase shifting is sometimes referred to as delaying. Pulses are also referred to as doses.

[0045] In Figure 2, "Outlet A" and "Outlet B" refer to the flows of gases A and B at the gas source outlet, respectively. In sequence 210, both gas flows begin at time t1 with no delay. In sequence 220, because there is a delay in gas A, the flow of gas A from the gas source outlet begins at time t2.

[0046] In some embodiments, this method is implemented by specifying one or more parameters. For example, the user may specify the delay by entering the following parameters: [Table 1]

[0047] The table above shows the following parameters. Delay refers to the time delay between gases A and B flowing from the gas source outlet. In one example, the delay is 0.5 seconds. In some embodiments, there are two types of delays: one where the dose is shortened, and another where the purge between consecutive doses is shortened. In the table above, the delay type parameter is 0 for shortening the dose and 1 for shortening the purge. The delay gas parameter indicates which gas is delayed; for example, 0 to delay B and 1 to delay A.

[0048] It should be noted that the dose begins when the valve that flows to the showerhead is open. This is referred to as the “gas source,” and the gas source can be a charge container, a distribution line, or any other container or line containing gas. In some embodiments, the charge container and / or distribution line are housed in a gas box.

[0049] A parallel flow sequence can be used as a reference, where there is no delay, the purge times after A and B are equal, and the dose times for gas A and gas B are equal. In some embodiments, cycles A and B can be terminated simultaneously by shortening either the dose or the purge. In other embodiments, both the post-purge and gas dose may be shortened relative to the other. Also, in some embodiments, the dose and purge times may be the same, but the entire cycles of A and B may be staggered. However, in many embodiments, the doses overlap.

[0050] Figure 3 shows the timing sequences for two examples with a delay in B in two cycles of parallel flow pulses of process gases A and B. The timing sequences for gas "A" and gas "B" respectively represent bypass, line charge, dose, and purge. The deposition station through which the gas flows may have a line that bypasses directly to the process's vacuum discharge so that the process gas can avoid the deposition station. A gas manifold system may be used to perform line charge on various gas distribution lines. Line charge refers to pressurizing the distribution lines. In certain embodiments, a charge vessel may be used, as will be further described below. After an appropriate time extension, the outlet valve of the charge vessel is opened and the gas is supplied to the chamber. After an appropriate gas supply time (dose time), the valve is closed, and the chamber can be purged. The delay of dose and / or purge is not dependent on the specific form of supply to the chamber, such as whether or not there is bypass and / or line charge.

[0051] In the example in Figure 3, in 310, there is a delay in B, and the dose time is shorter than that of A. The purge of A and B remain the same. In 320, there is a delay in B, and the purge time is shorter. The doses of A and B remain the same.

[0052] In the delays of B shown in 310 and 320, it may be assumed that argon gas or other purge gas is flowing from the inlet of B to the deposit station, or that nothing is flowing. The Dawes begins when the valve that allows flow to the station is opened and ends (or the flow stops) when the valve is closed. gas A dose is sometimes referred to as a gas pulse.

[0053] In some embodiments, delays compensate for varying feed times to the substrate. Such differences may be due, for example, to differences in flow rate, or to the location or capacity of the gas box, feed line, or showerhead plenum. Thus, as shown in Figure 2, if there is a delay in pulse A at the outlet of the gas box or other feed source, it may result in "true parallel flow" at the wafer. In one example, the delay shown at 220 in Figure 2 results in true parallel flow at the wafer as shown at 420 in Figure 4.

[0054] Figure 5 shows an example of transient simulation results for the mass fraction of NH3 and the position of WF6 relative to the center of the wafer, generated by the simulation. In each plot, the lines represent 0.2 seconds, 0.3 seconds, 0.4 seconds, 0.5 seconds, 0.6 seconds, 0.7 seconds, 0.8 seconds, 0.9 seconds, 1 second, 1.3 seconds, 1.7 seconds, and 3 seconds. This result indicates that NH3 reaches the wafer before WF6. Therefore, in the example in Figure 5, the lag of NH3 behind WF6 allows both gases to reach the wafer simultaneously.

[0055] Typically, the delay required to enable parallel flow on a wafer is shorter than the dose time itself, so that both doses overlap on the time axis. However, if, for example, the difference in the time it takes to reach the wafer is longer than the dose time, the two doses may not overlap.

[0056] In another embodiment, the dose delay may result in a delay at the wafer surface, which can be advantageous in certain processing.

[0057] While experimental or simulation results can be used to help determine which gas is lagging and by how much, it should be noted that in some embodiments, the methods described herein do not rely on a detailed or complete understanding of the gas flow at the wafer surface.

[0058] In some embodiments, the delay may be calculated by optimizing results such as uniformity and / or performance characteristics. Figure 6 shows an example of calculating the delay to improve uniformity within the wafer using two suppression processes. Regarding delays in various gas flows, WF 6 Low NH 3 / WF 6 Due to the parallel flow suppression process Delays in nucleation at wafer edges and center 、 Measured and displayed in plot 610 So The left side of the plot shows the delay results for WF6, and the right side shows the delay results for NH3.

[0059] The delay at the center and the delay at the edge are represented by separate curves, and they are closest at the position indicated by box 611, with the delay for NH3 being approximately 0.5 to 1 second. This indicates the best uniformity from the center to the edge. The non-uniformity within the wafer (WiW NU) was measured for no delay and for optimal delay. This delay reduced the WiW NU from 7% to 3.5%.

[0060] In the NH3 / WF6 parallel flow suppression process with a high WF6 flow rate, a similar plot 620 was observed. In this case, the best uniformity was obtained with a WF6 delay of approximately 1 to 2 seconds. WiW was compared between no delay and the case with an optimal delay. NU This was measured. Due to this delay, WiW NU decreased from 8% to 5%.

[0061] In addition to, or instead of, uniformity, delay can be used to tune specific performance characteristics. For example, a delay of approximately 0.5 to 1 second may be used in low WF6 processes to maximize edge suppression.

[0062] In addition to suppression processes, the methods and apparatus described herein may be implemented in other pulsed parallel-flow processes. One example is an atomic layer deposition (ALD) process in which one of the reactants flows in parallel with another gas. For example, Figure 7 shows an example timing sequence graph illustrating an exemplary cycle for depositing a tungsten nucleation layer using diborane. As shown in Figure 7, hydrogen flows only during the diborane pulse. By flowing H2 in parallel with the boron-containing reducing agent but not with the flow of the tungsten-containing precursor, the step coverage and conformation of the nucleation layer can be improved. Figure 8 shows a timing sequence with a short dose delay of B2H6.

[0063] The processes described herein may be used with any chamber and gas delivery system configured to deliver two or more gases separately into the chamber. Figure 9a shows an example of a two-part plenum showerhead configured to deliver two gases separately into the chamber. In the example in Figure 9a, WF6 and NH3 are delivered. WF6 is delivered through the upper plenum and NH3 is delivered through the lower plenum, and the gases remain separate until they exit the showerhead. A single plenum showerhead may also be used, in which case the gases may be mixed within the showerhead. Regardless of the showerhead, different gas sources may be connected to the showerhead, for example, as shown in Figure 9b, which shows a configuration for depositing a metal nucleation layer using the aforementioned B2H6 / H2 parallel flow. Figure 10 is a schematic diagram of the gas flow including a mass flow controller (MFC), a charge container (CV), and an outlet valve connected to the showerhead. As previously mentioned, the dose begins when the outlet valve is opened to allow gas to flow from the gas source (gas box in the example in Figure 10) to the showerhead.

[0064] In other embodiments, one of the two reactant flows may be in a mode that flows continuously through a suppression process or other process, while the other reactant flow is pulsed, with or without delay. This also enables parallel flow on the wafer.

[0065] Metal-containing precursors In certain embodiments, this method may be used as part of a suppressed deposition process, including a DID process, for films of cobalt, molybdenum, or ruthenium, or films of compounds containing these metals. While WF6 is used above as an example of a tungsten-containing precursor, it should be understood that other tungsten-containing precursors may be suitable for carrying out the disclosed embodiments. For example, metal organotungsten-containing precursors may be used. Organometallic precursors such as MDNOW (methylcyclopentadienyl-dicarbonylnitrosyl-tungsten) and EDNOW (ethylcyclopentadienyl-dicarbonylnitrosyl-tungsten) and fluorine-free precursors may also be used. Chlorine-containing tungsten precursors such as tungsten pentachloride (WCl5) and tungsten hexachloride (WCl6) may also be used. x You may use ).

[0066] To deposit molybdenum (Mo), Mo-containing precursors such as molybdenum hexafluoride (MoF6), molybdenum pentachloride (MoCl5), molybdenum dichloride (MoO2Cl2), molybdenum tetrachloride (MoOCl4), and hexacarbonylmolybdenum (Mo(CO)6) may be used.

[0067] Ruthenium (Ru) precursors may be used to deposit ruthenium. Examples of ruthenium precursors that may be used in oxidation reactions include (ethylbenzyl)(1-ethyl-1,4-cyclohexadienyl)Ru(0), (1-isopropyl-4-methylbenzyl)(1,3-cyclohexadienyl)Ru(0), (2,3-dimethyl-1,3-butadienyl)Ru(0) tricarbonyl, (1,3-cyclohexadienyl)Ru(0) tricarbonyl, and (cyclopentadienyl)(ethyl)Ru(II) dicarbonyl. Examples of ruthenium precursors that react with non-oxidizing reactants are bis(5-methyl-2,4-hexanediketonate)Ru(II) dicarbonyl and bis(ethylcyclopentadienyl)Ru(II).

[0068] To deposit cobalt (Co), cobalt-containing precursors such as dicarbonylcyclopentadienylcobalt(I), cobalt carbonyl, various cobalt amidinate precursors, cobalt diazadienyl complexes, cobalt amidinate / guanidinate precursors, and combinations thereof may be used.

[0069] As mentioned above, metal-containing precursors can react with reducing agents. In some embodiments, H2 is used as a reducing agent for depositing the bulk layer to deposit a high-purity film.

[0070] Deposition of nucleation layers In some implementations, the methods described herein include depositing a nucleation layer before depositing the bulk layer. The nucleation layer is typically a thin, conformal layer that facilitates the subsequent deposit of the bulk material. For example, the nucleation layer may be deposited on the wafer surface at consecutive points before and / or during feature filling (e.g., via interconnects). For example, in some implementations, the nucleation layer may be deposited after etching tungsten within the features and before the initial tungsten deposit.

[0071] In certain embodiments, the first deposit in the DID process is a nucleation layer. The first deposit may be a bulk layer or a nucleation + bulk layer.

[0072] In certain implementation configurations, the nucleation layer is deposited using pulsed nucleation layer (PNL) technology. In PNL technology for depositing tungsten nucleation layers, pulses of a reducing agent, an optional purge gas, and a tungsten-containing precursor are sequentially injected and purged from the reaction chamber. This process is repeated periodically until the desired thickness is reached. PNL encompasses atomic layer deposition (ALD) technology and broadly embodies any periodic process of sequentially adding reactants to react on a semiconductor substrate. The thickness of the nucleation layer can vary depending on the deposition method and the desired quality of the bulk deposition. Generally, the thickness of the nucleation layer is sufficient to maintain a high-quality, uniform bulk deposition. For example, it may be in the range of 10 Å to 100 Å.

[0073] The methods described herein are not limited to specific methods of nucleation layer deposition, but include depositing a bulk film on a nucleation layer formed by any method such as PNL, ALD, CVD, and physical vapor deposition (PVD). Furthermore, in certain implementations, bulk tungsten may be deposited directly onto a feature without using a nucleation layer. For example, in some implementations, the feature surface and / or already deposited underlying layers support the bulk deposition. In some implementations, a bulk deposition process without a nucleation layer may be implemented.

[0074] In various implementations, the deposition of tungsten nucleation layers may involve exposure to tungsten-containing precursors such as tungsten hexafluoride (WF6), tungsten hexachloride (WCl6), and tungsten hexacarbonyl (W(CO)6). In certain implementations, the tungsten-containing precursor is a halogen-containing compound such as WF6. Organometallic precursors and fluorine-free precursors such as MDNOW (methylcyclopentadienyl-dicarbonylnitrosyl-tungsten) and EDNOW (ethylcyclopentadienyl-dicarbonylnitrosyl-tungsten) may also be used.

[0075] Examples of reducing agents include boron-containing reducing agents containing diborane (B2H6) and other boranes, silicon-containing reducing agents containing silane (SiH4) and other silanes, hydrazine, and Gelmane. In some implementations, the metal-containing pulses can alternate with pulses of one or more reducing agents, for example, S / W / S / W / B / W, where W represents a tungsten-containing precursor, S represents a silicon-containing precursor, and B represents a boron-containing precursor. In some implementations, no separate reducing agent is used; for example, the tungsten-containing precursor may undergo thermal decomposition or plasma-assisted decomposition.

[0076] The metal precursors for other metals are listed above.

[0077] Bulk deposit As described above, bulk deposition may be performed across the entire wafer. In some packaging configurations, bulk deposition can be carried out by a CVD process in which a reducing agent and a metal-containing precursor flow into a deposition chamber to deposit a bulk packed layer within the features. An inert carrier gas may be used to deliver the flow of one or more reactants, and the reactants may or may not be pre-mixed. Unlike PNL and ALD processes, this operation generally requires the reactants to flow continuously until the desired amount is deposited. In certain packaging configurations, the CVD operation may be carried out in multiple stages, with multiple periods of continuous flow of reactants separated by periods of flow in which one or more reactants bypass the reactants. Bulk deposition may also be carried out using an ALD process in which a metal-containing precursor alternates with a reducing agent such as H2.

[0078] It should be understood that the metal films described herein may contain some amount of other compounds and dopants and / or impurities such as nitrogen, carbon, oxygen, boron, phosphorus, sulfur, silicon, and germanium, depending on the specific precursor and process used. The metal content in the film may range from 20% to 100% (atoms). In many packaging configurations, the film is metal-rich, containing at least 50% (atoms), and even at least about 60%, 75%, 90%, or 99% (atoms). In some packaging configurations, the film may be a mixture of a metal or elemental metal (e.g., W, Mo, Co, or Ru) and other metal-containing compounds such as tungsten carbide (WC), tungsten nitride (WN), or molybdenum nitride (MoN). CVD and ALD deposition of these materials may include the use of any suitable precursor described above.

[0079] In some embodiments, the first and second depositions of the DID process include bulk deposition using an ALD process with H2 as the reducing agent. The metal precursors were described above. Suppression of metal nucleation

[0080] Thermal inhibition processes generally involve exposing features to nitrogen-containing compounds such as ammonia (NH3) or hydrazine (N2H4) to inhibit features non-conformally near their openings. In some embodiments, thermal inhibition is carried out at temperatures in the range of 250°C to 450°C. At such temperatures, exposure of a previously formed tungsten layer or other layer to NH3 produces an inhibitory effect. For thermal inhibition at even higher temperatures (e.g., 900°C), other potentially inhibitory chemicals such as nitrogen (N2) or hydrogen (H2) may be used. However, in many applications, such high temperatures exceed the thermal history. In addition to ammonia, other hydrogen-containing nitrides such as hydrazine may be used at lower temperatures suitable for back-end obline (BEOL) applications.

[0081] By nitriding a surface, it can be passivated. Subsequent deposition of tungsten or other metals such as molybdenum or cobalt onto a nitrided surface is significantly slower compared to deposition on a normal bulk tungsten film. In addition to NF3, fluorocarbons such as CF4 or C2F8 may be used. However, in certain packaging configurations, the inhibitory species does not contain fluorine to prevent etching during the inhibitory process.

[0082] In addition to the surfaces mentioned above, nucleation may be suppressed on the surfaces of the liner / barrier layer, such as TiN and / or WN. Any chemicals may be used to passivate these surfaces. Suppression chemicals may also be used to adjust the suppression profile by using effective suppressing species in various proportions. For example, when suppressing W surfaces, nitrogen may have a stronger suppressing effect than hydrogen, and the profile can be adjusted by changing the ratio of N2 gas to H2 gas in the forming gas.

[0083] In certain implementation configurations, the substrate can be heated or cooled before suppression. A predetermined temperature of the substrate can be selected to induce a chemical reaction between the feature surface and the suppression species and / or to promote the adsorption of the suppression species, and to control the rate of the reaction or adsorption. For example, a temperature may be selected to increase the reaction rate so that more suppression occurs near the gas source.

[0084] In some embodiments, suppression may involve a thermal chemical reaction between the suppressing species and the feature surface to form a thin layer of composite material, such as a metal nitride film. In some embodiments, suppression may involve surface effects, such as adsorption, to passivate the surface without forming a layer of composite material.

[0085] Embodiments of the methods described herein are not limited to specific inhibiting chemicals. Inhibiting gases may be referred to as reactive inhibiting gases, regardless of the mechanism of inhibition. This is distinct from inert gases such as helium (He) and argon (Ar), as well as other non-reactive gases that may be used to guide gas flow without reacting or causing surface effects.

[0086] As described above, in the method described herein, a metal precursor gas may be passed through during the inhibition process. According to various embodiments, the presence of the precursor may cause a small amount of film to deposit during the inhibition process.

[0087] Device The method described herein may be carried out using various types of deposition equipment available from various vendors. Examples of suitable equipment include Concept-1 ALTUS®, Concept2 ALTUS®, Concept-2 ALTUS-S®, Concept3 ALTUS® deposition systems, ALTUS Max®, ALTUS® Max ICEFill®, or any of the various other commercially available deposition tools. Both single-station and multi-station deposition equipment can be used to carry out the above method.

[0088] Figure 11 shows an apparatus 1160 that may be used according to the various methods described above. The deposition station 1102 has a substrate support 1103 that supports the wafer during the deposition process. A exclusion ring 1100 and a showerhead 1105 are shown. As discussed above, the processing gas may be supplied through the showerhead 1105, the substrate support is provided with a vacuum, and in some embodiments, a processing gas source is provided. In some embodiments, the showerhead 1105 is a two-part plenum showerhead. If the substrate support is provided with a processing gas source, the suppression processing gas (e.g., NH3) may flow through the showerhead as well as through the substrate support to the back and / or edges of the wafer. In such cases, the back processing gas may be pulsed together with the front processing gas and flow continuously while the front processing gas is pulsed, or otherwise flow in an appropriate manner.

[0089] To provide information about the station's status in various embodiments, gas sensors, pressure sensors, temperature sensors, etc., may be used. Examples of station sensors that can be monitored in operation include mass flow controllers, pressure sensors such as manometers, thermocouples placed on the pedestal, and infrared detectors for monitoring the presence of gas in the station. In certain embodiments, a controller 1174 is used to control the station's processing status. Further details regarding the types of controllers are discussed below with reference to Figure 11, and the discussion relating to this figure is applicable to station and chamber controllers. Sensors such as 1176 may be used to provide information about controller 1174.

[0090] Figure 12 shows an example of a multi-station device that may be used in a particular embodiment. The device 1200 has a processing chamber 1201 that houses a plurality of stations. The processing chamber can house at least two stations, or at least three stations, or at least four stations or more. Figure 12 shows the device 1200 having four stations 1231, 1232, 1233, and 1234. In some embodiments, all stations of the multi-station device 900 having the processing chamber 1201 may be exposed to the same pressure environment controlled by a system controller 1274. Sensors (not shown) may also be provided, including pressure sensors to provide readings of the chamber pressure. However, each station may have separate temperature conditions or other conditions.

[0091] In the deposition process, the wafer to be processed may be loaded into station 1231 via a load lock. At this station, the deposition process for the nucleation layer and / or bulk layer may be carried out. The wafer may then be intermittently fed to station 1232 for suppression processing, including the delay described above. Bulk deposition may then be carried out at stations 1233 and 1234. In other embodiments, the processing may be carried out at the same station as one or both of the deposition operations of the DID sequence. Furthermore, any of these operations may be carried out in separate chambers.

[0092] In one example, the first deposition involves alternately adding a metal precursor and a reducing agent at a first station, followed by transporting the substrate to a second station for a delayed suppression treatment, and then transporting the substrate to a third station for a second deposition, which involves alternately adding a metal precursor and a reducing agent at the first station. Exemplary deposition sequences are shown in Figures 7 and 8. In some embodiments, an H2 reducing agent (with or without parallel flow) may be used.

[0093] The system controller 1274 can control the intermittent feed state, the station state, and the state of the processing chamber, such as the gas flow and chamber pressure. The system controller 1274 (which may include one or more physical or logical controllers) controls some or all of the operation of the processing chamber 1200. The system controller 1274 may include one or more memory devices and one or more processors. In some implementations, the system controller 1274 is part of the system, and the system may be part of the embodiments described above. Such a system may include a semiconductor processing apparatus comprising one or more processing tools, one or more chambers, one or more platforms for processing, and / or specific processing components (such as a wafer pedestal, a gas flow system). These systems may be integrated with electronics that control the operation of the system before, during, and after processing semiconductor wafers or substrates. The electronics may be integrated with the system controller and may control various components or sub-parts of one or more systems. The system controller may be programmed to control any of the processes disclosed herein, depending on the processing parameters and / or the type of system, such as supplying processing gas, setting temperature (e.g., heating and / or cooling), setting pressure, setting vacuum, setting flow rate and number of cycles, setting fluid supply, setting potential and operation, transporting wafers into and out of tools and other transport tools, and / or load locks connected to or interfaced with a particular system.

[0094] Generally, a system controller may be defined as an electronic device having various integrated circuits, logic circuits, memory, and / or software that receive and issue instructions, control operations, enable cleaning operations, enable endpoint measurements, and so on. The integrated circuit may comprise a firmware-like chip that stores program instructions, a digital signal processor (DSP), a chip defined as an application-specific integrated circuit (ASIC), and / or one or more microprocessors, or a microcontroller that executes program instructions (e.g., software). Program instructions may be instructions transmitted to the controller in the form of various separate settings (or program files) that define operating parameters for performing operations on or for a semiconductor wafer, or for the system. In some embodiments, the operating parameters may be part of a recipe defined by a processing engineer to achieve one or more processing steps in the process of manufacturing or removing one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or wafer dies.

[0095] In some implementations, the system controller may be part of a computer that is integrated with the system, networked with the system, or a combination of both, or connected to this computer. For example, the controller may be in the “cloud” or be part of a fab host computer system that enables remote access to wafer processing. The computer may enable remote access to the system to monitor the current progress of a manufacturing operation, investigate the history of past manufacturing operations, investigate trends or performance metrics from multiple manufacturing operations, change parameters for the current process, set processing steps to follow the current process, or start a new process. In some examples, a remote computer (e.g., a server) may provide processing recipes to the system over a network, which may include a local network or the internet. The remote computer may include a user interface that allows input or programming of parameters and / or settings, which are then transmitted from the remote computer to the system. In some examples, the system controller receives instructions in data form that specify parameters for each processing step performed during one or more operations. The parameters may be specific to the type of processing performed and the type of tool that the controller is configured to interface with or control. Therefore, as mentioned above, the system controllers may be distributed by having one or more separate controllers that are networked together and function toward a common purpose, such as processing and control as described herein. An example of a distributed controller for this purpose would be one or more integrated circuits located on a chamber that communicates with one or more integrated circuits located remotely (for example, at the platform level or as part of a remote computer), and which work together to control processing on this chamber.

[0096] Examples of systems may include, but are not limited to, plasma etching chambers or modules, deposition chambers or modules, spin rinse chambers or modules, metal plating chambers or modules, cleaning chambers or modules, bevel edge etching chambers or modules, physical vapor deposition (PVD) chambers or modules, chemical vapor deposition (CVD) chambers or modules, ALD chambers or modules, ALE chambers or modules, ion implantation chambers or modules, track chambers or modules, and any other semiconductor processing systems that may be used in connection with or for the manufacture and / or production of semiconductor wafers.

[0097] As described above, depending on one or more processing steps performed by the tool, the controller may communicate with one or more tools used for transporting materials to and from tool locations and / or loading ports within the semiconductor manufacturing plant, other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, neighboring tools, tools located throughout the plant, a main computer, another controller, or wafer containers.

[0098] Patterning method / apparatus The aforementioned apparatus / processes may be used in conjunction with lithography patterning tools or processes for the fabrication or manufacture of semiconductor devices, displays, LEDs, photovoltaic panels, etc. Typically, such tools / processes are used or performed together in a common manufacturing facility, though not always. Film lithography patterning typically includes some or all of the following steps, each of which can be performed with many possible tools: (1) Applying photoresist to a workpiece, i.e., a substrate, using a spin-on or spray-on tool. (2) Curing the photoresist using a hot plate or furnace or a UV curing tool. (3) Exposing the photoresist to visible light, UV light, or X-ray light using a tool such as a wafer stepper. (4) Developing the resist to selectively remove it, thereby patterning the resist using a tool such as a wet bench. (5) Transferring the resist pattern to the underlying film or workpiece using a dry etching or plasma-assisted etching tool. And (6) Removing the resist using a tool such as an RF or microwave plasma resist stripper. The present invention can also be realized in the following embodiments, for example. Application Example 1: It is a method, The suppression process on the substrate in the chamber is performed by flowing parallel pulses of a reactivity suppression gas from a first gas source and a metal precursor gas from a second gas source into the chamber, each parallel pulse includes a pulse of the reactivity suppression gas and a pulse of the metal precursor gas, and the pulses of the reactivity suppression gas and the pulse of the metal precursor gas overlap with a time difference when measured from the time each gas flows from the gas source, and the suppression process suppresses metal nucleation. Methods that include... Application example 2: A method according to claim 1, wherein the pulse of the metal precursor gas and the pulse of the reactivity suppressing gas terminate or start simultaneously. Application Example 3: A method according to claim 1, wherein each pulse of the reactivity-suppressing gas is separated from subsequent pulses of the reactivity-suppressing gas by a purge, and each pulse of the metal precursor gas is separated from subsequent pulses of the metal precursor gas by a purge. Application Example 4: A method according to any one of claims 1 to 3, wherein the metal is one of tungsten (W), molybdenum (Mo), cobalt (Co), and ruthenium (Ru). Application Example 5: A method according to claim 1, wherein the reactivity-inhibiting gas contains nitrogen. Application example 6: The method according to claim 1, wherein the reactivity-inhibiting gas is ammonia (NH₃). 3 ) or hydrazine (N 2 H 4 ) is a method. Application example 7: A method according to claim 1, further comprising calculating a deviation from a delay parameter. Application Example 8: A method according to claim 8, wherein the displacement is calculated by optimizing the uniformity within the wafer. Application example 9: A method according to claim 1, further comprising depositing a first metal layer on the substrate prior to the suppression treatment. Application Example 10: A method according to claim 9, further comprising depositing a second metal layer on the substrate after the suppression treatment. Application Example 11: A method according to claim 10, wherein the deposition of the first metal layer is performed at a first station of a multi-station chamber, the suppression treatment is performed at a second station of a multi-station chamber, and the deposition of the second metal layer is performed at a third layer of a multi-station chamber. Application Example 12: A method according to claim 1, wherein the reactivity-inhibiting gas and the metal precursor gas are mixed only after they have exited the showerhead. Application Example 13: It is a device, A chamber comprising one or more stations, each station having a pedestal and a showerhead positioned above the pedestal and configured to be fluidly connected to a first gas source and a second gas source; It is a controller, A controller, including instructions, for introducing a plurality of parallel pulses of the first gas and the second gas into a station in the chamber, each parallel pulse comprising a pulse of the first gas and a pulse of the second gas, wherein the pulses of the first gas and the pulses of the second gas overlap with a time lag, each pulse of the first gas is separated from subsequent pulses of the first gas via a purge, and each pulse of the second gas is separated from subsequent pulses of the second gas via a purge. A device having. Application Example 14: The apparatus according to claim 13, wherein the controller further includes an instruction for calculating a deviation from one or more parameters. Application Example 15: The apparatus according to claim 13, wherein the controller further includes an instruction for receiving the one or more parameters. Application Example 16: Apparatus according to claim 15, wherein one or more parameters include the identifiability of the gas to be delayed, the length of the delay, and whether to shorten the pulse or purge. Application Example 17: An apparatus according to any one of claims 13 to 16, wherein the controller further includes instructions for modifying the sequence of pulses of the first gas or the second gas in accordance with the calculated deviation. Application Example 18: It is a method, The method involves introducing a plurality of parallel pulses of a first gas and a second gas into a processing chamber, each of which includes a pulse of the first gas from a first gas source and a pulse of the second gas from a second gas source, wherein the pulses of the first gas and the pulses of the second gas overlap with a time lag when measured from the point in time when each gas flows from the gas source, each pulse of the first gas is separated from subsequent pulses of the first gas via a purge, and each pulse of the second gas is separated from subsequent pulses of the second gas via a purge. method. Application Example 19: A method according to claim 18, further comprising calculating a deviation from one or more parameters. Application Example 20: A method according to claim 19, further comprising receiving one or more of the parameters. Application Example 21: A method according to claim 20, wherein one or more parameters include the identifiability of the gas to be delayed, the length of the delay, and whether to shorten the pulse or purge. Application Example 22: A method according to any one of claims 18 to 21, further comprising modifying the pulse sequence of the first gas or the second gas in accordance with the calculated deviation. Application Example 23: A tangible machine-readable medium, Multiple parallel pulses of a first gas and a second gas are introduced into a processing chamber, each parallel pulse comprising a pulse of the first gas and a pulse of the second gas, wherein the pulses of the first gas and the pulses of the second gas overlap with a time lag, each pulse of the first gas is separated from subsequent pulses of the first gas via a purge, and each pulse of the second gas is separated from subsequent pulses of the second gas via a purge. A tangible, machine-readable medium containing instructions. Application Example 24: A tangible machine-readable medium according to claim 23, further comprising instructions for calculating a deviation from one or more parameters. Application Example 25: A tangible machine-readable medium according to claim 23, further comprising an instruction for receiving one or more parameters from user input. Application Example 26: A tangible machine-readable medium according to claim 24, wherein one or more parameters include the identifiability of the delayed gas, the length of the delay, and whether to shorten the pulse or purge. Application Example 27: A tangible machine-readable medium according to any one of claims 23 to 26, further comprising modifying the sequence of pulses of the first gas or the second gas in accordance with the calculated deviation.

Claims

1. A computer, A tangible computer-readable medium recording a program for introducing a plurality of parallel pulses of a first gas and a second gas into a processing chamber, wherein each parallel pulse includes a pulse of the first gas and a pulse of the second gas, the pulses of the first gas and the pulses of the second gas overlap with a time lag, each pulse of the first gas is separated from subsequent pulses of the first gas via a purge, and each pulse of the second gas is separated from subsequent pulses of the second gas via a purge.

2. A tangible computer-readable medium according to claim 1, further comprising an instruction for calculating a deviation from one or more parameters.

3. A tangible computer-readable medium according to claim 1, further comprising an instruction for receiving one or more parameters from user input.

4. A tangible computer-readable medium according to claim 2, wherein one or more parameters include the identifiability of the delayed gas, the length of the delay, and whether to shorten the pulse or purge.

5. A tangible computer-readable medium according to any one of claims 2 to 4, further comprising instructions for modifying the sequence of pulses of the first gas or the second gas in accordance with the calculated deviation.

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