Hybrid deposition and etch process for improved gap fill

Abstract

A method of performing bottom-to-top gap filling of features of a substrate at a process temperature below 400 DEG C with a metal halide precursor and simultaneous introduction of a reducing agent and a halogen-containing etchant into a processing chamber is provided. A selective gap filling process may be used to fill the feature with a transition metal comprising molybdenum or tungsten. Some methods involve the use of a metal halide precursor and a halogen-containing etchant, wherein both the precursor and the etchant comprise the same halogen and / or pulsed plasma power.

Description

[0001] Related applications The PCT application forms are filed together with this specification as part of this application. Each application identified in the concurrently filed PCT application forms that claims a benefit or priority under this application is incorporated herein by reference in its entirety for all purposes. Background Technology

[0002] The deposition of conductive materials is an integral part of many semiconductor manufacturing processes. These materials are used for horizontal interconnects, vias between adjacent metal layers, contacts between metal layers and devices, and circuitry in memory devices. However, with the shrinking of device dimensions and the increasing complexity of patterning schemes in industry, the deposition of tungsten thin films has become a challenge.

[0003] The background description provided herein is for the purpose of presenting the general context of this disclosure. The work of the currently designated inventor, within the scope described in this background section and in aspects of the specification that could not be identified as prior art at the time of filing, neither expressly nor impliedly acknowledges that it is prior art to this disclosure. Summary of the Invention

[0004] Specific embodiments herein relate to methods and apparatus for filling features on a semiconductor substrate. In certain cases, the features are filled using a combined method of deposition and etching operations contained within the same processing chamber. This method allows for bottom-up gap filling of substrate features by utilizing a metal halide precursor and simultaneously introducing a reducing agent and a halogen-containing etchant into the processing chamber at process temperatures below 400°C. The delivery duration of the halogen-containing etchant may be the same as, or shorter than, the delivery duration of the reducing agent. This selective gap filling process can be used to fill these features using transition metals comprising molybdenum or tungsten. Some methods involve the use of a metal halide precursor and a halogen-containing etchant, wherein the precursor and the etchant contain the same halogen and / or pulsed plasma power.

[0005] Therefore, in a first aspect, this disclosure includes a method for bottom-up gap filling of features of a substrate. In some embodiments, the method includes: (a) providing a substrate comprising a plurality of features in a processing chamber, each feature comprising a feature opening and a feature bottom; (b) introducing a metal halide precursor into the processing chamber; (c) introducing a reducing agent into the processing chamber; and (d) introducing a halogen-containing etchant into the processing chamber; wherein the duration of (d) occurs during the duration of (c); and the duration of (d) is equal to or shorter than the duration of (c), such that the metal halide precursor reacts with the reducing agent to deposit a metal film in the feature, and the halogen-containing etchant preferentially etches the metal film near the feature opening relative to the metal film near the feature bottom.

[0006] In some implementations, the bottom-up gap filling is performed by atomic layer deposition, plasma-enhanced atomic layer deposition, pulsed chemical vapor deposition, or plasma-enhanced chemical vapor deposition.

[0007] In some embodiments, the metal film is molybdenum or tungsten.

[0008] In some implementations, the reducing agent is hydrogen.

[0009] In some embodiments, the halogen-containing etchant and the metal halide precursor contain the same halogen.

[0010] In some embodiments, the metal halide precursor is a molybdenum halide precursor or a tungsten halide precursor.

[0011] In some embodiments, the halogen-containing etchant is HCl, Cl2, MoCl5, HBr, HF, F2, MoF6, or a combination thereof.

[0012] In some embodiments, the molybdenum halide precursor is a molybdenum halide, a molybdenum oxyhalide, or a combination thereof.

[0013] In some embodiments, the molybdenum halide is molybdenum dichloride, molybdenum trichloride, molybdenum tetrachloride, molybdenum pentachloride, molybdenum hexachloride, molybdenum hexafluoride, or molybdenum fluoride.

[0014] In some embodiments, the molybdenum oxyhalide is molybdenum dichlorodioxide, molybdenum tetrachlorodioxide, molybdenum tetrafluorodioxide, or molybdenum dibromodioxide.

[0015] In some embodiments, the tungsten halide precursor is tungsten hexafluoride, tungsten pentafluoride, tungsten hexachloride, tungsten pentachloride, or a combination thereof.

[0016] In some implementations, the ratio of reducing agent to etchant is from about 10:1 to about 1:10.

[0017] In some implementations, the concentration of the etchant increases or decreases during (d).

[0018] In some implementations, the duration of (b) is the same as the duration of (c).

[0019] In some embodiments, the substrate is not removed from the processing chamber during or between any of operations (a) to (d).

[0020] In some implementations, the temperature of the processing chamber is maintained below about 400°C.

[0021] In some embodiments, the temperature of the processing chamber is maintained at about 200°C to about 300°C, and the processing chamber has a pressure of less than about 500 Torr.

[0022] In a second aspect, this disclosure includes means for filling features of a semiconductor substrate. In some embodiments, the means includes: one or more processing chambers; one or more gas inlets leading to the processing chambers and associated flow rate control hardware; and a controller having at least one processor and a memory, wherein the processor and the memory are communicatively connected to each other, the at least one processor is at least operatively connected to the associated flow rate control hardware, and the memory stores computer-executable instructions for controlling the at least one processor to at least control the associated flow rate control hardware to: (a) introduce a metal halide precursor into the processing chamber; (b) introduce a reducing agent into the processing chamber; and (c) introduce a halogen-containing etchant into the processing chamber; and wherein the duration of (c) occurs during the duration of (b); and the duration of (c) is equal to or shorter than the duration of (b).

[0023] In some embodiments, the apparatus further includes a plasma generator to supply pulsed plasma to the one or more processing chambers.

[0024] In a third aspect, this disclosure includes a method for bottom-up gap filling of features of a substrate. In some embodiments, the method includes: (a) providing a substrate comprising a plurality of features in a processing chamber, each feature comprising a feature opening and a feature bottom; (b) introducing a metal halide precursor into the processing chamber; (c) introducing a reducing agent into the processing chamber; and (d) introducing a halogen-containing etchant into the processing chamber; wherein the duration of (c) occurs during the duration of (d); and the duration of (c) is equal to or shorter than the duration of (d), whereby the metal halide precursor reacts with the reducing agent to deposit a metal film in the feature, and the halogen-containing etchant preferentially etches the metal film near the feature opening relative to the metal film near the feature bottom.

[0025] These and other aspects are further described below with reference to the accompanying drawings. Attached Figure Description

[0026] Figure 1 is a flowchart of a metal deposition method with combined deposition and etching operations according to a specific disclosed embodiment.

[0027] Figure 2 is a flowchart of another metal deposition method with combined deposition and etching operations according to a specific disclosed embodiment.

[0028] Figure 3 is a schematic diagram of a metal deposition method (I) and a conventional metal deposition method (II) in a plasma-enhanced atomic layer deposition method with parallel co-flow reducing agent and etchant according to a specific disclosed embodiment.

[0029] Figure 4 is a schematic diagram of a combined deposition and etching operation in a plasma-enhanced atomic layer deposition method according to a specific disclosed embodiment, the combined deposition and etching operation having an etchant co-flowing during the introduction of a reducing agent portion and two scavenging steps (I) or one scavenging step (II) per cycle.

[0030] Figure 5A is a schematic diagram of a combined deposition and etching operation in a pulsed chemical vapor deposition method according to a specific disclosed embodiment.

[0031] Figure 5B is a schematic diagram of a combined deposition and etching operation in a plasma-enhanced atomic layer deposition method according to a specific disclosed embodiment, the combined deposition and etching operation having a co-current of reducing agent pulses during the introduction of the etchant portion.

[0032] Figure 5C is a schematic diagram of a combined deposition and etching operation in a plasma-enhanced atomic layer deposition method, which features co-current of etchant pulses during partial introduction of the reducing agent.

[0033] Figure 6 is a schematic diagram of a combined deposition and etching operation in a plasma-enhanced chemical vapor deposition method according to a specific disclosed embodiment.

[0034] Figure 7 is a schematic diagram of an apparatus suitable for depositing metals according to a specific disclosed embodiment.

[0035] Figure 8 shows a schematic diagram of a multi-station processing system according to a specific publicly disclosed implementation.

[0036] Figure 9 shows a schematic diagram of a multi-station processing system according to a specific publicly disclosed implementation. Detailed Implementation

[0037] In the following description, numerous specific details are set forth to provide a complete understanding of these embodiments. The disclosed embodiments may be practiced without some or all of these specific details. In other examples, well-known process operations are not described in detail to avoid unnecessarily obscuring the disclosed embodiments. Although the disclosed embodiments will be described in conjunction with specific embodiments, it should be understood that it is not intended to limit these disclosed embodiments.

[0038] definition As used herein, the term "about" is understood to mean a small increase and / or decrease beyond the value that does not significantly affect the expected function of the parameter beyond the value. In some cases, "about" includes + / - 10% of any of the values. As used herein, the term modifies any of the values, numerical ranges, or endpoints of one or more ranges.

[0039] As used herein, the terms “top,” “bottom,” “upper,” “lower,” “above,” and “below” are used to provide a relative relationship between structures. The use of these terms does not imply or require that a particular structure must be located in a specific position within the apparatus.

[0040] As used herein, the term “at least one of A, B, and C” should be understood to represent the logic of using the non-exclusive logic “or” (A or B or C) and should not be understood to represent “at least one A, at least one B, and at least one C”.

[0041] For the purposes of this disclosure, the term "metal" as used in the context can be understood to mean a conductor with a maximum resistivity of 500 microohm-cm, including metals and conductive metal salts, particularly conductive metal nitrides, such as TiN.

[0042] In this disclosure, the terms "semiconductor wafer," "wafer," "substrate," "wafer substrate," and "partially manufactured integrated circuit" are used interchangeably. Those skilled in the art will understand that the term "partially manufactured integrated circuit" can refer to a silicon wafer at any of the various stages of integrated circuit manufacturing. Wafers or substrates used in the semiconductor equipment industry typically have diameters of 200 mm, 300 mm, or 450 mm. The detailed description below assumes that this disclosure is implemented on a wafer. However, this disclosure is not so limited. The workpiece can be of various shapes, sizes, and materials. Besides semiconductor wafers, other workpieces that can utilize this disclosure include a variety of different objects such as printed circuit boards.

[0043] Introduction & Background Chemical vapor deposition (CVD) is a process used to deposit thin films for semiconductor fabrication. CVD typically involves introducing one or more reagents (i.e., precursors) into a substrate within a processing chamber. These reagents react and / or decompose to deposit these films. Plasma-enhanced CVD (PECVD) uses plasma in this processing chamber to increase the reaction rate of these reagents and allows deposition at lower temperatures. Plasma species can also be used to modulate the properties of the resulting films.

[0044] ALD is a technique for depositing thin layers of material using a sequential, self-limiting reaction. The ALD process utilizes surface-mediated deposition reactions to cyclically deposit films layer by layer. For example, an ALD cycle may include the following operations: (i) precursor delivery / adsorption, (ii) precursor removal from the chamber, (iii) delivery of a second reactant and optional plasma ignition, and (iv) removal of byproducts from the chamber.

[0045] Figure 1 is a flowchart depicting a method 100 of mixed deposition and etching according to a specific disclosed embodiment. This method can be described as mixed deposition and etching because a reducing agent and an etchant are introduced into the processing chamber simultaneously. In some embodiments, the simultaneous supply of the two reagents can be completely simultaneous when the reducing agent and the etchant flow into the processing chamber for the same duration as further explained and depicted in Figure 3. As used herein, “simultaneously” or “occurring simultaneously” means that the time periods or durations of reagent delivery or flow are the same. “Completely simultaneous” means that one reagent is delivered for a first duration and another reagent is delivered for a second duration, wherein the overlap between the two durations is 95-100%. “Partially simultaneous” means that one reagent is delivered for a first duration and a second reagent is delivered for a second duration, wherein the second duration is within the first duration but shorter than the first duration. In a particular embodiment, the method is a cryogenic process, wherein the processing chamber is maintained at the following temperatures: approximately 350ºC or lower, 300ºC or lower, 250ºC or lower, 200ºC or lower, 150ºC or lower, or 100ºC or lower.

[0046] The substrate may be a silicon wafer, such as a 200mm, 300mm, or 450mm wafer, comprising a wafer having one or more material layers, such as dielectric, conductive, or semiconductor materials deposited thereon. In various embodiments, the substrate is patterned. The patterned substrate may have "features" such as pillars, posts, recesses, vias, or contact holes, which may be characterized by one or more narrow and / or re-entrant openings, contractions in the feature, and a high aspect ratio. An example of a feature is a hole or via in a semiconductor substrate or a layer on the substrate. Another example is a recess in a substrate or layer. Yet another example of a feature is a pillar or post in a semiconductor substrate or a layer on the substrate.

[0047] Features typically have a depth-to-width ratio (depth to lateral dimension). Features with a high depth-to-width ratio may have the following depth-to-lateral dimension ratios: equal to or greater than approximately 10:1, equal to or greater than approximately 15:1, equal to or greater than approximately 20:1, equal to or greater than approximately 25:1, equal to or greater than approximately 30:1, equal to or greater than approximately 40:1, equal to or greater than approximately 50:1, or equal to or greater than approximately 100:1.

[0048] In various implementations, this feature may have an underlying layer, such as a barrier layer or an adhesive layer. Non-limiting examples of the underlying layer include dielectric and conductive layers, such as silicon oxide, silicon nitride, undoped silicon carbide, oxygen-doped silicon carbide, nitrogen-doped silicon carbide, metal oxide, metal nitride, metal carbide, and metal layers.

[0049] These features can be formed in one or more of the aforementioned layers.

[0050] The methods described herein can be used to fill vertical features formed in a substrate. Such features may be referred to as gaps, grooves, negative features, unfilled features, or simply features. Filling such features is called gap filling.

[0051] In some embodiments, features such as pillars may have aspect ratios of at least about 1:1, at least about 2:1, at least about 4:1, at least about 6:1, at least about 10:1, or higher. These features may also have dimensions close to the size of an opening, for example, an opening diameter or linewidth between about 10 nm and about 500 nm, such as between about 25 nm and about 300 nm. The disclosed method can be performed on a substrate having features with openings less than 150 nm.

[0052] Through-holes, recesses, or other recessed features may be referred to as unfilled features or features. Depending on the embodiment, the feature profile may gradually narrow and / or include overhangs at the feature opening. A concave profile is a feature that narrows from its bottom closed end or interior to the feature opening. Concave profiles may be created by asymmetric etch kinetics during patterning and / or by overhangs resulting from non-conformal film steps in previous film deposition (e.g., diffusion barrier deposition).

[0053] The substrate features can be of various types. In some embodiments, the features may have straight sidewalls, positively sloping sidewalls, or negatively sloping sidewalls. In some embodiments, the features may have sidewall morphology or sidewall roughness, which may be due to the etching process used to form the feature. In some embodiments, the feature may have a feature opening that is larger at the top than at the bottom, or the feature may have a feature opening that is larger at the bottom than at the top. In some embodiments, the feature may be partially filled with material or have one or more sublayers. The gap filling of features such as those in any of the embodiments described above may depend on the feature type and profile.

[0054] Because many deposition processes lack good step coverage properties, i.e., more material forms near the field area and opening (or the “neck” of the feature) than inside the feature, overhangs (or breadstick-like structures) are formed. For the purposes of this embodiment section, “near the opening” or “near the feature opening” is defined as an approximate location or region within the feature (i.e., along the sidewall of the feature) corresponding to approximately 0-10% of the feature depth measured from the field area, and in some embodiments may include the upper portion of the feature sidewall. In a particular embodiment, the region near the opening corresponds to the region located at the opening. Furthermore, “inside the feature” is defined as an approximate location or region within the feature corresponding to approximately 20-60% of the feature depth measured from the field area at the top of the feature. For the purposes of this embodiment section, “near the bottom” or “near the feature bottom” is defined as an approximate location or region within the feature (i.e., along the sidewall of the feature) corresponding to approximately 0-40% of the feature depth measured from the bottom of the feature.

[0055] Generally, when a particular parameter (e.g., thickness) is specified as "near the opening" or "inside the feature," these values ​​represent measurements taken at these locations / regions or the average of multiple measurements. In a particular embodiment, the average thickness of the deposited metal near the opening is at least about 10% compared to the interior of the feature. In more specific embodiments, this difference may be at least about 25%, at least about 50%, or at least about 100%. To achieve gap filling without creating overhangs, the hybrid deposition and etching methods disclosed herein can be used.

[0056] The deposition method according to this disclosure can be used to deposit transition metals such as nickel (Ni), cobalt (Co), copper (Cu), molybdenum (Mo), ruthenium (Ru), iridium (Ir), platinum (Pt), palladium (Pd), and tungsten (W). In some embodiments, this deposition method is used for metal gap filling in contact holes and mid-stage processes (MOL) and back-end processes (BEOL) grooves / through holes. In some embodiments, the liner comprises titanium / titanium nitride (TiN), tungsten carbide nitride (WCN), or tantalum / tantalum nitride (TaN). Alternatively, this deposition process can be used for oxide sidewalls or any other metal or dielectric barrier material.

[0057] Returning to Figure 1, operation 102 involves introducing a metal precursor into a processing chamber containing a semiconductor substrate. The choice of the precursor depends on the metal film to be deposited on the substrate. In a particular embodiment, the metal is tungsten (W) or molybdenum (Mo). The precursor may be introduced in vaporized form in a stream of inert gas such as argon, helium, or nitrogen (N2).

[0058] Tungsten deposition can be achieved using a variety of volatile precursors. In some implementations, halogenated tungsten precursors, such as WHal, are used. x Where Hal is a halogen (e.g., F, Cl, Br, and / or I) and x is from 2 to 6. In some embodiments, tungsten chloride is used. Tungsten chloride comprises: tungsten pentachloride (WCl5), tungsten hexachloride (WCl6), tungsten tetrachloride (WCl4), tungsten dichloride (WCl2), and mixtures thereof. In other examples, tungsten fluorides such as tungsten hexafluoride (WF6) can be used. In some embodiments, the tungsten-containing precursor is tungsten hexacarbonyl (W(CO)6), WCl5, WCl6, or WF6.

[0059] Molybdenum deposition can be achieved, for example, using a molybdenum precursor having two (MoL2) to six (MoL6) ligands (where molybdenum can be in a wide range of oxidation states from 0 to +6). Suitable molybdenum precursors can also be bismolybdenum compounds having 1) two molybdenum atoms that are single-bonded or multi-bonded to each other; or 2) two molybdenum atoms that are linked by a linking group such as a bidentate ligand.

[0060] In some embodiments, these molybdenum precursors comprise: molybdenum hexacarbonyl (Mo(CO)6); molybdenum halide precursors such as molybdenum tetrachlorooxygenate (MoOCl4) or molybdenum dichlorodioxide (MoO2Cl2); and molybdenum halide precursors such as molybdenum chloride ([MoCl5]2) or molybdenum hexafluoride (MoF6).

[0061] Other metals, such as aluminum, gallium, indium, bismuth, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, chromium, rhenium, rhenium, rhodium, ruthenium, osmium, or platinum, can be deposited using the following metal precursors: AlCl3, GaCl3, InCl3, BiCl3, BiF5, TiF4, TiCl4, ZrCl4, HfCl4, VF5, VCl4, NbF5, NbCl5, TaF5, TaCl5, CrF5, CrF5, TcF6, ReF6, ReF7, Re2Cl 10 RhF5, RhF6, RuF5, RuF6, OsF6 and PtF6.

[0062] The metal halide precursor can flow for approximately 50 ms to approximately 10,000 ms.

[0063] Operation 104 is a selective purging step. Purging the chamber may involve circulating a purging gas or cleaning gas, which may be a carrier gas used in other operations or may be a different gas. In some embodiments, the purging step may include evacuating the chamber. Exemplary purging gases include: argon (Ar), nitrogen (N2), hydrogen (H2), helium (He), oxygen (O2), krypton (Kr), xenon (Xe), neon (Ne), and combinations thereof. In various embodiments, the purging gas is an inert gas. The purging gas may contain one or more gases. In some embodiments, operation 104 may include one or more evacuation sub-stages for evacuating the processing chamber. Additionally, it should be understood that in some embodiments, the purging step may be omitted. Operation 104 may have any suitable duration, for example, between about 0 seconds and about 60 seconds, such as about 0.01 seconds.

[0064] In some implementations, increasing the flow rate of one or more purge gases can reduce the purge duration. For example, the purge gas flow rate can be adjusted based on the different thermodynamic and / or geometric characteristics of the reactants in the processing chamber and / or processing chamber piping to adjust the purge duration. In a non-limiting example, the duration of the purge phase can be adjusted by regulating the purge gas flow rate. This can shorten the deposition cycle time, thereby increasing substrate yield.

[0065] The purge gas can flow into the chamber containing the substrate at a flow rate between about 1,000 sccm and about 40,000 sccm (e.g., about 100 sccm to about 2,000 sccm). The purge gas can flow for any effective time period (e.g., about 0.1 to 10 seconds) and at any effective pressure (e.g., about 0.5 to 25 Torr).

[0066] In operation 106, at least one etchant and at least one reducing agent are simultaneously introduced into the processing chamber. As used herein, "simultaneously" or "at the same time" means that the time period or duration of reagent delivery or flow is the same. As shown in operation 106, the time period or duration of etchant delivery and reducing agent delivery is the same. Although the etchant and the reducing agent are delivered at the same time, they may each be delivered at different flow rates. Furthermore, the concentration of the etchant may remain constant or be different (i.e., gradually increase or gradually decrease) throughout its delivery duration. The ratio of reducing agent to etchant can be adjusted to achieve the desired result or property of the deposited metal. These properties include, but are not limited to, the deposition rate, uniformity, resistivity, thickness, and step coverage of the film. Adjustments can also be used to adjust the whole-wafer uniformity of these properties.

[0067] In some implementations, the ratio of reducing agent to etchant is from about 10,000:1 to about 10:1. The flow rate, concentration, and ratio of the etchant can be the same in each cycle or can be adjusted independently between cycles.

[0068] The reducing agent is typically a reducing gas. Suitable examples of reducing agents include H2, SiH4, NH3, or B2H6. In some embodiments, the reducing agent may be in plasma form, such as hydrogen plasma.

[0069] In some embodiments, the reducing agent is hydrogen, ammonia, hydrazine, silane, disilane, trisilane, germanane, digerane, diborane, or a combination thereof.

[0070] Exposing the substrate to the reducing agent may include contacting the substrate with the reducing agent for the following durations: between about 0.1 seconds and about 180 seconds; between about 0.5 seconds and about 60 seconds; or between about 0.1 seconds and about 10 seconds. During this exposure of the substrate, the flow rate of the reducing agent may be less than 30 slm, or less than 15 slm, or less than 10 slm, or less than 5 slm, or less than 2 slm, or even less than 0.1 slm in some embodiments. The flow rate range of the reducing agent may be from about 0.1 to 30 slm, from about 5 to 15 slm, or equal to or greater than 10 slm.

[0071] "Etching agent" refers to any compound used to remove materials such as layers, byproducts, or contaminants from a surface. In some embodiments, the etchant is a halogen-containing etchant, such as chlorine (Cl2), fluorine (F2), bromine (Br2), iodine (I2), hydrogen chloride (HCl), hydrogen fluoride (HF), hydrogen iodide (HI), chlorine trifluoride (ClF3), trifluoromethane (CHF3), fluoromethane (CH3F), octafluorocyclobutane (C4F8), hexafluorobutadiene (C4F6), hexafluorocyclopentadiene (C5F6), carbon tetrafluoride (CF4), nitrogen trifluoride (NF3), boron trichloride (BCl3), boron trifluoride (BF3), hydrogen iodide (HI), hydrogen bromide (HBr), sulfur tetrafluoride (SF4), sulfur hexafluoride (SF6), thionyl chloride (SOCl2), phosphorus pentafluoride (PF5), or combinations thereof.

[0072] In some embodiments, a single etchant may be sufficiently effective. In some embodiments, a combination of more than one etchant may be used. Examples of combinations include oxygen (O2) with one of the aforementioned halogenated etchants, such as chlorine and oxygen; or fluorine and oxygen. Alternatively, carbon dioxide (CO2) may be combined with one of the aforementioned halogenated etchants. If a combination of etchants is used, they may flow together (in conjunction) or sequentially (one after another) through the delivery line. The etchants may be co-flowed with an inert gas such as argon. In some embodiments, the etchants are combined. For example, a halogenated etchant may be co-flowed with a halogen-free etchant.

[0073] In some implementations, the etchant is MoCl5, MoF6, or any other metal halide mentioned above.

[0074] The etchant flow rate typically depends on the chamber size, etch rate, etch uniformity, and other parameters. These are generally much lower than the reducing agent flow rate. For example, the flow rate of a 195-liter chamber per station can range from 25 sccm to about 10,000 sccm, or in some embodiments, from about 50 sccm to about 1,000 sccm. In specific embodiments, the flow rate is below about 2,000 sccm, below about 1,000 sccm, or more specifically below about 500 sccm. It should be noted that these values ​​are for a single station configured to process a 300mm wafer substrate. The flow rate can be scaled up or down depending on the substrate size, the number of stations in the apparatus (e.g., four times for a four-station apparatus), the processing chamber volume, and other factors.

[0075] The etchant can be delivered to the processing chamber for a duration of approximately 0.1 to approximately 10 seconds.

[0076] In some embodiments, the etchant or etchant combination is halogen-containing, and the halogen of the etchant in operation 106 is the same as the halogen substituent on the metal halide precursor used in operation 102. For example, if the deposited metal is molybdenum, a chlorinated molybdenum precursor containing MoO2Cl2 or MoCl5 can be used with a chlorinated etchant such as HCl / Cl2; or a fluorinated molybdenum precursor such as MoF6 can be used with a chlorinated etchant such as HBr / HF / F2. If the deposited metal is tungsten, a chlorinated tungsten precursor WCl5 can be used with a chlorinated etchant such as HCl / Cl2; or a fluorinated tungsten precursor WF6 can be used with a fluorinated etchant such as HBr / HF / F2.

[0077] Without being constrained by theory, a general choice of halogen for both the etchant and the precursor can help enhance etching of the top surface and upper sidewalls of the feature; overcoming the formation of any overhangs in the breadcrumb-like structure near the feature's opening. The breadcrumb or breadcrumb-like structure can also be referred to as a bottleneck. Furthermore, choosing a reducing agent such as hydrogen to use with the halogen-containing etchant can be advantageous, as the reactive species of these halogen-containing etchants may be relatively heavier in atomic weight than the reactive substances of hydrogen, inducing these reactive species of the halogen-containing etchant to remain near the feature's opening and preferentially etch therein. When using such a combination, top-heavy etching (i.e., etching more etchant near the opening than at the bottom of the feature) mixed with the deposition results in superconducting deposition of the metal; thus improving gap filling.

[0078] Operation 108 is a second selective cleaning step. In process 100, cleaning operations 104 or 108 may be included; both cleaning operations 104 and 108 may be included; or a cleaning step may not be used.

[0079] In operation 110, it is determined whether the deposited metal has the desired thickness. As used herein, "metal" refers to a film containing only metal or a metal-containing film with additional components. Metals can be deposited for a variety of different semiconductor applications. Therefore, the desired thickness will depend on the specific application. In some embodiments, metals can be deposited as a conformal layer with a thickness between about 0.1 nm and 10 nm on a substrate.

[0080] If a thicker film is desired, operation 112 is the process flow path, indicating that operation 102 can be restarted after operation 106, and the process repeated. n Next. In process flow path 112, n The number of cycles can range from 1 to 50 or from 20 to 40. The cycles of operations 102 and 106, and selective cleaning operation 104, can be repeated multiple times as needed. As used herein, the term "cycle" refers to a specific set of sequential operations.

[0081] Figure 2 is a flowchart according to a specific disclosed embodiment, depicting another method 200 of hybrid deposition and etching. Method 200 depicts the simultaneous supply of a reducing agent and an etchant, the etchant flowing into the processing chamber during the reducing agent delivery, but the reducing agent delivery may continue after the etchant is introduced into the processing chamber or begin before the etchant is introduced into the processing chamber. Such a situation is depicted in Figures 4, 5A, 5C and 6 and is further described below.

[0082] Returning to Figure 2, operation 202 involves introducing a metal precursor into the processing chamber and is similar to operation 102 described previously.

[0083] Operations 204 and 208 are selective cleaning operations, which are similar to the cleaning operations 104 and 108 described previously.

[0084] Operation 206 involves introducing a reducing agent and an etchant into the processing chamber. The etchant is introduced during the introduction of the reducing agent. However, the reducing agent may additionally flow into the processing chamber before, after, or both before and after the introduction of the etchant. The flow of the reducing agent is thus partially simultaneous with the flow of the etchant. Alternatively, the reducing agent may be introduced in a pulsed manner during the etchant delivery.

[0085] Operation 210 is a decision operation similar to operation 110 described above. Operation 212 is a process path similar to process path 112, indicating that operations 206 and 202 can be repeated multiple times as needed until the desired thickness is achieved.

[0086] Figure 3 is a schematic diagram comparing thermal or plasma-enhanced atomic layer deposition (I) with parallel co-flow of reducing agent and etchant according to a specific disclosed embodiment with a conventional sequential metal deposition method (II). As shown in the figure of the conventional process (II), the precursor, reducing agent, and etchant are done sequentially, interspersed with a cleaning step. However, in the disclosed hybrid deposition and etching method, the reducing agent and etchant are introduced in parallel rather than sequentially. In this embodiment, the duration of etchant inflow into the processing chamber is the same as the duration of reducing agent inflow into the processing chamber.

[0087] As shown in Figure 3, pulsed power plasma can be used during the co-flow delivery of the reducing agent and the etchant. As used herein, "pulsed power plasma" represents a method in which a plasma source is turned on, igniting the plasma, and then the power of the plasma source is varied in pulses between two or more values. In a single duty cycle, the plasma source power can change as a step function, i.e., between discrete integer power values ​​or in a gradual "linear" manner. The power can also change periodically, i.e., from 500W to 0W to 500W to 0W, etc., or gradually, i.e., from 0W to 100W to 200W to 300W to 400W to 500W or 100W to 300W to 500W to 1000W, etc., where the gradual changes are not consistent, or are a combination of both, i.e., from 100W to 300W to 500W to 0W to 500W to 300W to 100W. Other arrangements of plasma power setpoints not specifically listed here are still considered to conform to “pulsed plasma power”. This power setpoint can be any number between 0W, 50W, and 3000W.

[0088] Pulsed plasma methods and systems are described, for example, in U.S. Patent No. 10,566,211, granted on February 18, 2020, entitled “CONTINUOUS AND PULSED RF PLASMA FOR ETCHING METALS”, the disclosure of which is incorporated herein by reference.

[0089] In some embodiments, the power ranges from about 50 W to about 3000 W. In some embodiments, the frequency of the plasma pulse ranges from about 1 Hz to about 400 kHz. In some embodiments, the duty cycle ranges from about 1% to about 99%.

[0090] Figure 4 is a schematic diagram of a combined deposition and etching operation according to a disclosed plasma-enhanced atomic layer deposition method, which features etchant co-flow during a portion of the introduction of the reducing agent, with two purging steps (I) or one purging step (II, also known as plasma-free purging PE ALD) per cycle. Skipping the purging after the plasma pulse allows the plasma to extinguish naturally.

[0091] Process I and Process II differ only in the cleaning steps. For either Process I or Process II, the etchant and reducing agent flow together, but the introduction of the reducing agent begins before the parallel co-flow of the reducing agent and etchant.

[0092] As shown in Figure 4, pulsed power plasma (as described above) can be used during the co-current transport of reducing agent and etchant.

[0093] Figure 5A is a schematic diagram of a combined deposition and etching operation in a pulsed chemical vapor deposition (PEALD) method according to a specific disclosed embodiment. This embodiment may also be referred to as a plasma-free PEALD method. In this embodiment, the etchant is also co-flowed with the reducing agent for a mixed-flow method. However, the etchant and reducing agent flows are only partially simultaneous, as the reducing agent flow is continuous while the etchant flow is pulsed on and off.

[0094] Additionally, as shown in Figure 5A, the pulsed power plasma (as described above) can be turned on during the flow of the reducing agent or during the co-flow transport of the reducing agent and the etchant.

[0095] Figure 5B is a schematic diagram of a combined deposition and etching operation in a plasma-enhanced atomic layer deposition method according to a specific disclosed embodiment, the combined deposition and etching operation having a reductant pulse co-flow during a portion of the etchant introduction. As depicted, multiple pulses of reductant can be delivered to the processing chamber during continuous etchant delivery. For example, in a particular embodiment, three one-second reductant pulses can be delivered to the processing chamber instead of a single three-second reductant pulse.

[0096] Additionally, as shown in Figure 5B, the pulsed power plasma (as described above) can be turned on during the continuous period of etchant delivery to the processing chamber; this also occurs simultaneously with the periodic delivery of the reducing agent pulses.

[0097] Figure 5C is a schematic diagram of a combined deposition and etching operation in a plasma-enhanced atomic layer deposition (PEALD) method, wherein etchant pulses co-flow during a portion of the reducing agent introduction. As depicted, multiple etchant pulses can be delivered to the processing chamber during continuous reducing agent delivery. For example, in a particular embodiment, three one-second etchant pulses can be delivered to the processing chamber instead of a single three-second etchant pulse.

[0098] Additionally, as shown in Figure 5C, the pulsed power plasma (as described above) can be turned on during the continuous delivery of the reducing agent to the processing chamber; this is also simultaneous with the periodic delivery of the etchant pulses.

[0099] Figure 6 is a schematic diagram of a combined deposition and etching operation in a plasma-enhanced chemical vapor deposition method according to a specific disclosed embodiment. In an embodiment of the disclosed hybrid method, both the precursor stream and the reducing agent stream are continuous, but the etchant stream is pulsed on and off. In this way, the etchant and reducing agent co-flow in a partially simultaneous manner.

[0100] Additionally, as shown in Figure 6, the pulsed power plasma (as shown above) can be turned on during the continuous delivery of the reducing agent and precursor to the processing chamber, which is also carried out simultaneously with the periodic delivery of the etchant pulse.

[0101] The foregoing description is illustrative in nature and is not intended to limit the scope of this disclosure, its application, or use. Extensive implementation of this disclosure can take many forms. Therefore, although this disclosure contains specific examples, the true scope of this disclosure is not to be considered in a limiting sense, as other modifications may become apparent when examining the illustrations, specifications, and the following claims; it is understood that one or more steps within a method may be performed in different orders (or in parallel) without altering the principles of this disclosure. Furthermore, although the foregoing embodiments are described as having specific features, any one or more of the features described for any embodiment of this disclosure, even if the combination is not explicitly described, may be implemented and / or combined with features of any other embodiment. In other words, the described embodiments are not mutually exclusive, and substitutions between one or more elements remain within the scope of this disclosure.

[0102] Device The deposition methods described herein can be performed in various apparatuses. Suitable apparatuses include a processing chamber having one or more inlets for introducing one or more reactants; a substrate holder located within the processing chamber and configured to hold the substrate in place during deposition; and optionally, a plasma generation mechanism configured to generate plasma in a process gas. The apparatus may include a controller having program instructions to cause the execution of any of the method steps described herein. The deposition methods described herein can be performed in appropriate ALD and CVD apparatuses.

[0103] Examples of deposition apparatus suitable for depositing metals using the provided methods are shown in Figure 7, which schematically illustrates an embodiment of a processing station 700 that can be used to deposit materials using atomic layer deposition (ALD) and / or chemical vapor deposition (CVD), either of which can be plasma-enhanced. For simplicity, the processing station 700 is depicted as a standalone processing station having a processing chamber body 702 for maintaining a low-pressure environment. However, it should be understood that multiple processing stations 700 may be included in a common processing tool environment. Furthermore, it should be understood that in some embodiments, one or more hardware parameters of the processing station 700, including those discussed in detail below, can be programmed by one or more computer controllers.

[0104] Processing station 700 is in fluid communication with reactant delivery system 701 to deliver process gas to distribution nozzle 706. Reactant delivery system 701 includes mixing container 704 for blending and / or conditioning process gas for delivery to nozzle 706. One or more mixing container inlet valves 720 can control the introduction of process gas into mixing container 704. Similarly, nozzle inlet valve 705 can control the introduction of process gas into nozzle 706.

[0105] Some molybdenum-containing precursors may be stored in solid or liquid form before vaporization and subsequent transport to the processing station. For example, the embodiment of Figure 7 includes a vaporization point 703 for vaporizing solid reactants to be supplied to mixing vessel 704. In some embodiments, vaporization point 703 may be a heated vaporizer. In some embodiments, an inert gas stream passes through a heated solid molybdenum precursor at a pressure below atmospheric pressure, or is bubbled through a heated liquid molybdenum precursor, transporting the precursor vapor to the processing chamber. The precursor vapor generated from such a vaporizer may condense in downstream delivery piping. Incompatible gases exposed to the condensed reactants can produce small particles. These particles can clog pipes, impede valve operation, contaminate substrates, etc. Some methods for addressing these problems involve purging and / or pumping out delivery piping to remove residual reactants. However, purging delivery piping increases processing station cycle time and reduces processing station throughput. Therefore, in some embodiments, the delivery piping downstream of vaporization point 703 may be heat-traced. In some examples, mixing vessel 704 may also be heat-traced. In a non-limiting example, the pipe downstream of vaporization point 703 has a temperature distribution that rises from about 100°C to about 200°C at mixing vessel 704.

[0106] Nozzle 706 dispenses process gas toward substrate 712. In the embodiment shown in Figure 7, substrate 712 is located below nozzle 706 and is shown mounted on base 708. It should be understood that nozzle 706 can have any suitable shape and can have any suitable number and arrangement of ports to dispense process gas to substrate 712. Although not explicitly shown, in some embodiments, nozzle 706 is a dual plenumshowerhead comprising at least two types of conduits, wherein the first type of conduit is dedicated to delivering molybdenum-containing precursor vapor, while the second type of conduit is dedicated to delivering a second (or other) reactant. In these embodiments, the molybdenum-containing precursor and reactant are not allowed to mix in the conduits before entering the processing chamber, and the conduits are not shared if continuously delivered to the processing chamber.

[0107] In some implementations, the microvolume 707 is located below the nozzle 706. Performing ALD and / or CVD processes in a microvolume, rather than throughout the entire volume of the processing station, reduces reactant exposure and purge time, reduces the time required to change process conditions (e.g., pressure, temperature, etc.), and limits the exposure of the processing station's robotic arms to process gases, etc. Exemplary microvolume sizes include, but are not limited to, volumes between 0.1 liters and 2 liters. This microvolume also impacts productivity throughput. As the deposition rate decreases per cycle, the cycle time also decreases. In some cases, for a given target film thickness, the reduction in cycle time is significant enough to improve the overall yield of the module.

[0108] In some embodiments, the base 708 can be raised or lowered to expose the substrate 712 to the microvolume 707 and / or the volume of the microvolume 707 can be altered. For example, during the substrate transfer stage, the base 708 can be lowered so that the substrate 712 can be loaded onto the base 708. During the deposition process stage, the base 708 can be raised to position the substrate 712 within the microvolume 707. In some embodiments, the microvolume 707 can completely surround the substrate 712 and a portion of the base 708 to form a region with high current resistance during the deposition process.

[0109] Optionally, the base 708 may be lowered and / or raised during portions of the deposition process to regulate process pressure, reactant concentration, etc., within the microvolume 707. In a configuration where the processing chamber body 702 is maintained at a base pressure during the deposition process, lowering the base 708 may allow the microvolume 707 to be evacuated. Exemplary ratios of microvolume to processing chamber volume include, but are not limited to, volume ratios between 1:700 and 1:10. It should be understood that in some embodiments, the base height may be programmatically adjusted via a suitable computer controller.

[0110] Although the exemplary microvolume changes described herein involve a highly adjustable base, it should be understood that in some embodiments, the position of the nozzle 706 can be adjusted relative to the base 708 to change the volume of the microvolume 707. Furthermore, it should be understood that the vertical position of the base 708 and / or the nozzle 706 can be changed by any suitable mechanism within the scope of this disclosure. In some embodiments, the base 708 may include a rotation axis for rotating the orientation of the substrate 712. It should be understood that in some embodiments, one or more of these exemplary adjustments can be performed programmatically by one or more suitable computer controllers.

[0111] Returning to the embodiment shown in Figure 7, the nozzle 706 and base 708 are electrically in communication with the RF power source 714 and matching network 716 for powering the plasma. In other embodiments, a device without a plasma generator is used to deposit a molybdenum-containing film using the provided method. In some embodiments, the plasma energy can be controlled by controlling one or more of the following: the pressure of the processing station, the concentration of the gas, the power of the radio frequency (RF) source, the RF source frequency, and the timing of the plasma power pulses. For example, the RF power source 714 and matching network 716 can operate at any suitable power to form a plasma with the desired composition of free radical material. Similarly, the RF power source 714 can provide RF power at any suitable frequency. In some embodiments, the RF power source 714 can be configured to control a high-frequency RF power source and a low-frequency RF power source that are independent of each other. Exemplary low-frequency RF frequencies may include, but are not limited to, frequencies between 50 kHz and 700 kHz. Exemplary high-frequency RF frequencies may include, but are not limited to, frequencies between 1.8 MHz and 2.45 GHz. It should be understood that any suitable parameters can be adjusted discretely or continuously to provide plasma energy for surface reactions. In a non-limiting example, the plasma power can be pulsed intermittently relative to a continuously powered plasma to reduce ion bombardment of the substrate surface.

[0112] In some embodiments, the plasma can be monitored in situ by one or more plasma monitors. In one case, plasma power can be monitored by one or more voltage and current sensors (e.g., VI probes). In another case, plasma density and / or the concentration of process gases can be measured by one or more optical emission spectrometers (OES). In some embodiments, one or more plasma parameters can be programmed to adjust based on measurements from such in-situ plasma monitors. For example, OES sensors can be used in feedback loops to provide programmable control of plasma power. It should be understood that in some embodiments, other monitors can be used to monitor plasma and other process characteristics. Such monitors may include, but are not limited to, infrared (IR) monitors, acoustic monitors, and pressure sensors.

[0113] In some implementations, the plasma can be controlled via input / output control (IOC) sequencing instructions. In one example, instructions for setting the plasma conditions for a plasma process stage may be included in a corresponding plasma activation formulation stage of the deposition process formulation. In some cases, the formulation stages may be arranged sequentially such that all instructions for the deposition process stage are executed concurrently with that process stage. In some implementations, instructions for setting one or more plasma parameters may be included in a formulation stage preceding the plasma process stage. For example, a first formulation stage may include instructions for setting the flow rates of the inert gas and / or reactant gas, instructions for setting the plasma generator to a power setpoint, and time delay instructions for the first formulation stage. A subsequent second formulation stage may include instructions for enabling the plasma generator and time delay instructions for the second formulation stage. A third formulation stage may include instructions for disabling the plasma generator and time delay instructions for the third formulation stage. It should be understood that these formulation stages may be further subdivided and / or iterated in any suitable manner within the scope of this disclosure.

[0114] In some embodiments, the temperature of the base 708 can be controlled by the heater 710. Furthermore, in some embodiments, pressure control of the deposition process station 700 can be provided by a butterfly valve 718. As shown in the embodiment of Figure 7, the butterfly valve 718 throttles the vacuum provided by a downstream vacuum pump (not shown). However, in some embodiments, the pressure control of the processing station 700 can also be adjusted by changing the flow rate of one or more gases introduced into the processing station 700.

[0115] Figure 8 illustrates a schematic embodiment of a multi-station processing tool 800, having an inbound loading lock 802 and an outbound loading lock 804, one or both of which may contain a remote plasma source. This tool can be used to process substrates using the methods provided herein. At atmospheric pressure, a robotic arm 806 is configured to move a wafer from a cassette loaded via a boat 808 through an atmospheric port 810 into the inbound loading lock 802. The wafer is placed on a base 812 within the inbound loading lock 802 by the robotic arm 806, the atmospheric port 810 is closed, and the loading lock is evacuated. When the inbound loading lock 802 contains a remote plasma source, the wafer can be exposed to remote plasma processing within the loading lock before being introduced into the processing chamber 814. Additionally, the wafer can also be heated in the inbound loading lock 802, for example, to remove moisture and adsorbed gases. Next, a chamber transfer port 816 leading to the processing chamber 814 is opened, and another robotic arm (not shown) places the wafer onto a base at the first station shown in the reactor for processing. Although the implementation shown in Figure 8 includes a loading lock, it should be understood that in some implementations, the wafer can be sent directly to the processing station.

[0116] The illustrated processing chamber 814 comprises four processing stations, numbered 1 to 4 in the embodiment shown in Figure 8. Each station has a heated base (shown as 818 for station 1) and a gas line inlet. It should be understood that in some embodiments, each processing station may have different or multiple uses. Although the illustrated processing chamber 814 comprises four stations, it should be understood that a processing chamber according to this disclosure may have any suitable number of stations. For example, in some embodiments, a processing chamber may have five or more stations, while in other embodiments, a processing chamber may have three or fewer stations.

[0117] Figure 8 also illustrates an embodiment of a wafer handling system 890 for transferring wafers within processing chamber 814. In some embodiments, the wafer handling system 890 can transfer wafers between various processing stations and / or between a processing station and a loading lock. It should be understood that any suitable wafer handling system can be employed. Non-limiting examples include wafer turntables and robotic arms for handling wafers. Figure 8 also illustrates an embodiment of a system controller 850 for controlling the process conditions and hardware status of processing tool 800. The system controller 850 may include one or more memory devices 856, one or more mass storage devices 854, and one or more processors 852. The processor 852 may include a CPU or computer, analog and / or digital input / output connections, a stepper motor controller board, etc.

[0118] In some implementations, system controller 850 controls all activities of processing tool 800. System controller 850 executes system control software 858 stored in mass storage device 854, loaded into memory device 856, and executed on processor 852. System control software 858 may contain instructions for controlling timing, gas mixing, chamber and / or station pressure, chamber and / or station temperature, purge conditions and timing, wafer temperature, RF power level, RF frequency, substrate, pedestal, chuck and / or pedestal position, and other parameters for specific processes performed by processing tool 800. System control software 858 may be configured in any suitable manner. For example, various processing tool component subroutines or control objects may be written to control the operation of processing tool components necessary to perform various processing tool processes according to the disclosed methods. System control software 858 may be coded in any suitable computer-readable programming language.

[0119] In some implementations, the system control software 858 may include input / output control (IOC) sequencing instructions for controlling the various parameters described above. For example, each stage of the ALD process may include one or more instructions executed by the system controller 850. Instructions for setting the process conditions for an ALD process stage may be included in the corresponding ALD formulation stage. In some implementations, the ALD formulation stages may be sequentially arranged such that all instructions for an ALD process stage are executed simultaneously with that process stage.

[0120] In some implementations, additional computer software and / or programs may be used, stored on mass storage device 854 and / or memory device 856 associated with system controller 850. Examples of programs or program segments used for this purpose include substrate positioning programs, process gas control programs, pressure control programs, heater control programs, and plasma control programs.

[0121] The substrate positioning procedure may include program code for a processing tool assembly that loads the substrate onto the base 818 and controls the spacing between the substrate and other parts of the processing tool 800.

[0122] The process gas control program may include code for controlling gas composition and flow rate, and optionally for allowing gas to flow into one or more processing stations prior to deposition to stabilize pressure within the processing station. The process gas control program may include code for controlling gas composition and flow rate within any disclosed range. The pressure control program may include code for controlling pressure within the processing station by adjusting, for example, throttling valves in the processing station's exhaust system, airflow into the processing station, etc. The pressure control program may include code for maintaining pressure within the processing station within any disclosed pressure range.

[0123] The heater control program may include code for controlling the current flowing to a heating element used to heat a substrate. Alternatively, the heater control program may control the delivery of a heat transfer gas (e.g., helium) to the substrate. The heater control program may include instructions for maintaining the temperature of the substrate within any publicly available range.

[0124] The plasma control program may include code for setting the RF power level and frequency applied to process electrodes in one or more processing stations, such as using any RF power level disclosed herein. The plasma control program may also include code for controlling the duration of each plasma exposure.

[0125] In some implementations, a user interface may be associated with the system controller 850. The user interface may include a display screen, a graphical software display of the device and / or process conditions, and user input devices such as pointing devices, keyboards, touch screens, microphones, etc.

[0126] In some implementations, the parameters regulated by the system controller 850 relate to process conditions. Non-limiting examples include process gas composition and flow rate, temperature, pressure, plasma conditions (e.g., RF power level, frequency, and exposure time), etc. These parameters can be provided to the user in the form of a recipe, which can be input using the user interface.

[0127] Signals used for process monitoring can be provided from various processing tool sensors via analog and / or digital input connections of system controller 850. Signals used for process control can be output via analog and / or digital output connections of processing tool 800. Non-limiting examples of processing tool sensors that can be monitored include mass flow rate controllers, pressure sensors (e.g., pressure gauges), thermocouples, and the like. Appropriately programmed feedback and control algorithms can be used with data from these sensors to maintain process conditions.

[0128] The disclosed implementation scheme can be implemented using any suitable room. Two or more stations can perform the same function. Similarly, two or more stations can perform different functions. Each station can be designed / configured as needed to perform a specific function / method.

[0129] Figure 9 is a block diagram of a processing system suitable for performing thin film deposition processes according to certain embodiments. System 900 includes a transfer module 903. Transfer module 903 provides a clean, pressurized environment to minimize the risk of contamination when the substrate being processed moves between the various reactor modules. According to certain embodiments, two multi-station reactors 909 and 910 are mounted on transfer module 903, each capable of performing atomic layer deposition (ALD) and / or chemical vapor deposition (CVD). Reactors 909 and 910 may include multiple stations 911, 913, 915, and 917, which may perform operations sequentially or non-sequentially according to the disclosed embodiments. These stations may include heated pedestals or substrate supports, one or more gas inlets or nozzles or dispersion plates.

[0130] Mounted on transfer module 903 may also be one or more single-station or multi-station modules 907 capable of performing plasma or chemical (non-plasma) pre-cleaning, or any other process related to the disclosed methods. In some cases, module 907 may be used for various processes, such as preparing substrates for deposition processes. Module 907 may also be designed / configured to perform various other processes, such as etching or polishing. System 900 also includes one or more wafer source modules 901 in which wafers are stored before and after processes. An atmospheric robot (not shown) in atmospheric transfer chamber 919 may first move wafers from source module 901 to loading lock 921. Wafer transfer device (typically a robotic arm unit) in transfer module 903 moves wafers from loading lock 921 to modules mounted on transfer module 903 and within modules mounted on transfer module 903.

[0131] In various implementations, the system controller 929 is used to control process conditions during the deposition process. The controller 929 typically includes one or more memory devices and one or more processors. The processor may include a CPU or calculator, analog and / or digital input / output connections, a stepper motor controller board, etc.

[0132] The controller 929 controls all activities of the deposition apparatus. The system controller 929 executes system control software, which includes sets of instructions for controlling timing, gas mixtures, chamber pressure, room temperature, wafer temperature, radio frequency (RF) power levels, wafer chuck or pedestal positions, and other parameters specific to the process. Additional computer programs stored in a memory device associated with the controller 929 may be employed in some embodiments.

[0133] Typically, there is a user interface associated with the controller 929. The user interface may include a display screen, a graphical software display of the device and / or process conditions, and user input devices such as pointing devices, keyboards, touch screens, microphones, etc.

[0134] System control logic can be configured in any suitable manner. Generally, this logic can be designed or configured in hardware and / or software. Instructions for controlling the drive circuitry can be hard-coded or provided as software. Instructions can be provided through "programming." This programming is understood to include any form of logic, including hard-coded logic in digital signal processors, application-specific integrated circuits (ASICs), and other devices with specific algorithms implemented in hardware. Programming is also understood to include software or firmware instructions executable on a general-purpose processor. System control software can be encoded in any suitable computer-readable programming language.

[0135] The computer program code used to control the germanium-containing reducing agent pulse, hydrogen flow rate, and tungsten-containing precursor pulse, as well as the computer program code for other processes in the process sequence, can be written in any common computer-readable programming language: for example, assembly language, C, C++, Pascal, Fortran, or others. The compiled object code or script is executed by the processor to perform the tasks identified in the program. Also, as indicated, the program code can be hard-coded.

[0136] Controller parameters are related to process conditions, such as process gas composition and flow rate, temperature, pressure, cooling gas pressure, substrate temperature, and chamber wall temperature. These parameters are provided to the user in the form of a formula and can be input via a user interface. Signals for monitoring the process can be provided through analog and / or digital input connections to the system controller 929. Signals for controlling the process are output through analog and digital output connections to the deposition apparatus 900.

[0137] System software can be designed or configured in many different ways. For example, according to the disclosed embodiments, various chamber component subroutines or control objects can be written to control the operation of chamber components necessary to perform the deposition process (and in some cases, other processes). Examples of programs or program segments used for this purpose include substrate positioning code, process gas control code, pressure control code, and heater control code.

[0138] In some implementations, controller 929 is part of a system, which may be part of the examples described above. Such a system may include semiconductor processing apparatus, which includes one or more processing tools, one or more chambers, one or more platforms for processing, and / or specific processing components (wafer pedestals, gas flow systems, etc.). These systems may be integrated with electronics for controlling their operation before, during, and after the processing of semiconductor wafers or substrates. The electronics may be referred to as a “controller”, which can control various components or sub-components of one or more systems. Depending on the processing requirements and / or system type, the controller may be programmed to control any process disclosed herein, including the delivery of processing gases, temperature settings (e.g., heating and / or cooling), pressure settings, vacuum settings, power settings, radio frequency (RF) generator settings, RF matching circuit settings, frequency settings, flow rate settings, fluid delivery settings, position and operation settings, wafer transfer tools and other transfer tools, and / or loading locks that are connected to or docked with a specific system.

[0139] In a broad sense, a controller can be defined as an electronic device having various integrated circuits, logic, memory, and / or software for receiving instructions, issuing instructions, controlling operations, enabling cleaning operations, enabling endpoint measurements, etc. Integrated circuits can include chips in the form of firmware storing program instructions, digital signal processors (DSPs), chips defined as application-specific integrated circuits (ASICs), and / or one or more microprocessors or microcontrollers that execute program instructions (e.g., software). Program instructions can be instructions sent to the controller in the form of various individual settings (or program files), which define operating parameters for performing a specific process on or for a semiconductor wafer or system. In some embodiments, operating parameters can be part of a recipe defined by a process engineer to complete one or more processing steps during the fabrication of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or wafer dies.

[0140] In some implementations, the controller may be part of or coupled to a computer integrated with, coupled to, or otherwise networked to the system. For example, the controller may be in the "cloud" or be all or part of a fab host system, allowing remote access to wafer processing. The computer may enable remote access to the system to monitor the current progress of manufacturing operations, examine the history of past manufacturing operations, examine trends or performance criteria of multiple manufacturing operations, change parameters of 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 process recipes to the system via a network (which may include a local network or the Internet). The remote computer may include a user interface that enables the input or programming of parameters and / or settings, which are then transmitted from the remote computer to the system.

[0141] In some examples, the controller receives instructions in the form of data specifying parameters for each processing step to be performed during one or more operations. It should be understood that the parameters can be specific to the type of process to be performed and the type of tool to which the controller is configured to interface with or control the tool. Therefore, as described above, the controller can be distributed, for example, by including one or more discrete controllers networked together and working toward a common purpose, such as the process and control described herein. An example of a distributed controller for such a purpose is one or more integrated circuits in the room communicating with one or more integrated circuits remotely (e.g., at the platform level or as part of a remote computer), which together control the process in the room.

[0142] Exemplary systems may include, but are not limited to, plasma etching chambers or modules, deposition chambers or modules, rotary rinsing chambers or modules, metal plating chambers or modules, cleaning chambers or modules, chamfering edge etching chambers or modules, physical vapor deposition (PVD) chambers or modules, chemical vapor deposition (CVD) chambers or modules, atomic layer deposition (ALD) chambers or modules, atomic layer etching (ALE) chambers or modules, ion implantation chambers or modules, track chambers or modules, and any other semiconductor processing systems that may be associated with or used for the manufacture and / or preparation of semiconductor wafers.

[0143] As described above, depending on one or more processing steps to be performed by the tool, the controller may communicate with one or more other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, neighboring tools, tools located throughout the plant, a host computer, another controller, or tools used in the transport of materials to and from the tool location and / or loading port in the semiconductor manufacturing plant.

[0144] Other implementation plans The apparatus and processes described herein can be used in conjunction with photolithographic patterning tools or processes, for example, for the fabrication or manufacture of semiconductor devices, displays, LEDs, photovoltaic panels, etc. Typically, although not necessarily, these apparatuses and processes will be used together or operated in a common manufacturing facility. Photolithographic patterning of a film typically involves some or all of the following steps, each step enabling multiple feasible tools: (1) applying a photoresist to a workpiece, i.e., a substrate, using a spin coater or spray coater; (2) curing the photoresist using a hot plate or oven or a UV curing tool; (3) exposing the photoresist to visible light or UV or X-rays using a tool such as a wafer stepper; (4) developing the photoresist to selectively remove the photoresist and thereby pattern it using a tool such as a wet cleaning station; (5) transferring the photoresist pattern to the underlying film or workpiece using a dry or plasma-assisted etching tool; and (6) removing the photoresist using a tool such as an RF or microwave plasma stripper.

[0145] in conclusion While the foregoing embodiments have been described in detail for ease of understanding, it is to be understood that specific changes and modifications may be made within the scope of the appended claims. It should be noted that there are many alternative methods of implementing these embodiments in terms of processes, systems, and apparatus. Therefore, these embodiments should be understood as exemplary rather than restrictive, and are not intended to limit the details provided herein.

Claims

1. A method for performing bottom-up gap filling for performing features on a substrate, comprising: (a) A substrate comprising multiple features is provided in a processing chamber, each feature including a feature opening and a feature bottom; (b) Introducing the metal halide precursor into the processing chamber; (c) Introducing the reducing agent into the processing chamber; and (d) Introducing a halogen-containing etchant into the processing chamber; and Wherein (d) is performed during the duration of (c); and the duration of (d) is equal to or shorter than the duration of (c), thereby the metal halide precursor reacts with the reducing agent to deposit a metal film in the feature, and the halogen-containing etchant preferentially etches the metal film near the opening of the feature relative to the metal film near the bottom of the feature.

2. The method according to claim 1, wherein the metal film comprises molybdenum or tungsten.

3. The method according to claim 1, wherein the reducing agent is hydrogen.

4. The method of claim 1, wherein the halogen-containing etchant and the metal halide precursor contain the same halogen.

5. The method of claim 1, wherein the metal halide precursor comprises a molybdenum halide precursor or a tungsten halide precursor.

6. The method according to claim 1, wherein the halogen-containing etchant comprises: HCl, Cl2, MoCl5, HBr, HF, F2, MoF6, or a combination thereof.

7. The method of claim 5, wherein the molybdenum halide precursor comprises: a molybdenum halide, a molybdenum oxyhalide, or a combination thereof.

8. The method according to claim 7, wherein the molybdenum halide comprises: molybdenum dichloride, molybdenum trichloride, molybdenum tetrachloride, molybdenum pentachloride, molybdenum hexachloride, molybdenum hexafluoride, or molybdenum fluoride.

9. The method according to claim 7, wherein the molybdenum oxyhalide comprises: molybdenum dichlorodioxide, molybdenum tetrachlorodioxide, molybdenum tetrafluorodioxide, or molybdenum dibromodioxide.

10. The method of claim 5, wherein the tungsten halide precursor comprises: tungsten hexafluoride, tungsten pentafluoride, tungsten hexachloride, tungsten pentachloride, or a combination thereof.

11. The method of claim 1, wherein the ratio of reducing agent to etchant is from about 10:1 to about 1:

10.

12. The method of claim 1, wherein the concentration of the etchant increases or decreases during (d).

13. The method of claim 1, wherein the duration of (b) is the same as the duration of (c).

14. The method according to claim 1, wherein, The substrate was not removed from the processing chamber during or between any of operations (a) to (d).

15. The method of claim 1, wherein the bottom-up gap filling is performed by atomic layer deposition, plasma-enhanced atomic layer deposition, pulsed chemical vapor deposition, or plasma-enhanced chemical vapor deposition.

16. The method of claim 1, wherein the temperature of the processing chamber is maintained below about 400°C.

17. The method of claim 16, wherein the temperature of the processing chamber is maintained at about 200°C to about 300°C, and the processing chamber has a pressure of less than about 500 Torr.

18. An apparatus for filling features of a semiconductor substrate, the apparatus comprising: One or more processing chambers; One or more gas inlets leading to the processing chamber and associated flow rate control hardware; and The controller has at least one processor and memory, wherein The at least one processor and the memory are communicatively connected to each other. The at least one processor is at least operatively connected to the associated flow rate control hardware, and The memory stores calculator-executable instructions for controlling the at least one processor to at least control the associated flow rate control hardware to: (a) Introducing a metal halide precursor into the processing chamber; (b) Introducing the reducing agent into the treatment chamber; and (c) Introducing a halogen-containing etchant into the processing chamber; and Wherein (c) is performed during the duration of (b); and the duration of (c) is equal to or shorter than the duration of (b).

19. The apparatus of claim 18, further comprising a plasma generator for supplying pulsed plasma to the one or more processing chambers.

20. A method for performing bottom-up gap filling for performing features on a substrate, comprising: (a) A substrate comprising multiple features is provided in a processing chamber, each feature including a feature opening and a feature bottom; (b) Introducing the metal halide precursor into the processing chamber; (c) Introducing the reducing agent into the processing chamber; and (d) Introducing a halogen-containing etchant into the processing chamber; and Wherein (c) is performed during the duration of (d); and the duration of (c) is equal to or shorter than the duration of (d), thereby the metal halide precursor reacts with the reducing agent to deposit a metal film in the feature, and the halogen-containing etchant preferentially etches the metal film near the opening of the feature relative to the metal film near the bottom of the feature.

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