Method for depositing tungsten and other metals within a 3D NAND structure

Abstract

Provided herein are methods and apparatus for filling features with a metal-containing material. One aspect of the present disclosure relates to a method for filling a structure with a metal-containing material, the method comprising preparing a structure to be filled with a metal-containing material and exposing the structure to multiple deposition cycles, each deposition cycle comprising exposure to one or more alternating reducing agent (e.g., hydrogen (H)) dose pulses / inert gas purge pulses, followed by one or more alternating metal precursor dose pulses and inert gas purge pulses. The metal, in some embodiments, may be tungsten (W) or molybdenum (Mo). In some embodiments, the structure is a partially fabricated (3D) NAND structure. Additionally, an apparatus for performing the method is provided. [Selected figure] Figure 3

Description

[Technical Field]

[0001] [Citation by reference] The PCT application is filed jointly with this specification as part of this application. Each application on which this application claims benefit or priority, as set forth in the jointly filed PCT application, is incorporated herein by reference in its entirety for any purpose. [Background technology]

[0002] The deposition of tungsten-containing materials is an essential part of many semiconductor manufacturing processes. Such materials may be used for horizontal wiring, vias between adjacent metal layers, and contacts between metal layers and devices. In conventional tungsten deposition processes, a substrate is heated to a processing temperature in a vacuum chamber to deposit a very thin portion of the tungsten film, which acts as a seed layer (also called the nucleation layer). Then, the remaining portion of the tungsten film (called the bulk layer) is deposited on top of the nucleation layer by simultaneously exposing the substrate to two reactants in a chemical vapor deposition (CVD) process. Generally, the bulk layer is deposited faster than the nucleation layer. However, as devices shrink and more complex patterning methods are employed in the industry, the deposition of tungsten thin films becomes a challenge. Deposition on complex, high-aspect-ratio structures such as 3D NAND structures is particularly difficult. [Overview of the Initiative] [Means for solving the problem]

[0003] This specification provides a method and apparatus for filling features with a metal-containing material. One aspect of the disclosure relates to a method for filling a structure with a metal-containing material, the method comprising preparing a structure to be filled with the metal-containing material and exposing the structure to a series of deposition cycles, each deposition cycle comprising one or more alternating reducing agent (e.g., hydrogen (H2)) dose pulses / inert gas purge pulses, followed by one or more alternating metal precursor dose pulses and inert gas purge pulses. In some embodiments, the metal may be tungsten (W) or molybdenum (Mo).

[0004] In some embodiments, the structure is a three-dimensional (3D) NAND structure in the process of being manufactured, which has side walls and a plurality of openings in the side walls, the openings leading to a plurality of features having a plurality of internal regions through which fluid access is possible. In some embodiments, the metal precursor is a chlorine-containing metal precursor such as tungsten hexachloride, tungsten pentachloride, tungsten tetrachloride, molybdenum pentachloride, molybdenum dichloride oxide, molybdenum tetrachloride oxide, and mixtures thereof. In some embodiments, the pulse of the chlorine-containing metal precursor contains between about 0.1% and about 5.0% of the chlorine-containing metal precursor by volume. In some embodiments, exposure to multiple alternating metal precursor pulses and inert gas purge pulses includes turning off the inert gas purge flow during the metal precursor pulses. In some embodiments, the duration of the inert gas purge pulse is at least 1.5 times the duration of the metal precursor pulse. In some embodiments, each deposition cycle includes at least 5 or at least 10 alternating metal precursor pulses and inert gas purge pulses. In some embodiments, each deposition cycle includes only one H2 pulse. In other embodiments, each deposition cycle includes multiple alternating H2 pulses and an inert gas pulse.

[0005] Other aspects of the present disclosure relate to a method for filling a structure with a metal-containing material, the method comprising preparing a structure to be filled with the metal-containing material and exposing the structure to multiple deposition cycles, each deposition cycle comprising exposure to a reducing agent (e.g., hydrogen (H2)) dose pulse, followed by exposure to an inert gas pulse, and further exposure to multiple alternating metal precursor dose pulses and inert gas purge pulses. In some embodiments, the structure is a three-dimensional (3D) NAND structure in the process of being manufactured, which has side walls and a plurality of openings in the side walls, the openings leading to a plurality of features having a plurality of fluid-accessible internal regions through the openings. In some embodiments, the metal precursor is a chlorine-containing metal precursor such as tungsten hexachloride, tungsten pentachloride, tungsten tetrachloride, molybdenum pentachloride, molybdenum dichloride oxide, molybdenum tetrachloride oxide, and mixtures thereof. In some embodiments, the pulse of chlorine-containing metal precursor contains between about 0.1% and about 5.0% of the chlorine-containing metal precursor by volume. In some embodiments, exposure to multiple alternating metal precursor pulses and inert gas purge pulses includes turning off the inert gas purge flow during the metal precursor pulses. In some embodiments, the duration of the inert gas purge pulse is at least 1.5 times the duration of the metal precursor pulse. In some embodiments, each deposition cycle includes at least 5 or at least 10 alternating metal precursor pulses and inert gas purge pulses.

[0006] Other aspects of the present disclosure relate to an apparatus comprising one or more processing chambers, each configured to hold a substrate; one or more processing gas inlets for coupling to a reducing agent (e.g., hydrogen (H2)) gas source, a metal precursor gas source, and an inert purge gas source; and a controller for controlling the operation of the apparatus, the controller including machine-readable instructions for performing multiple deposition cycles, each deposition cycle comprising: injecting hydrogen (H2) pulses into one or more processing chambers via one or more processing gas inlets; injecting inert purge gas pulses into one or more processing chambers via one or more processing gas inlets after the injection of H2 pulses; and injecting multiple alternating metal precursor pulses and inert gas purge pulses into one or more processing chambers via one or more purge gas inlets after the injection of inert purge gas pulses. In some embodiments, the metal precursor is a chlorine-containing metal precursor. In some embodiments, the instructions include instructions for turning off the inert gas purge flow during the metal precursor pulse. In some embodiments, the duration of the inert gas purge pulse is at least 1.5 times the duration of the metal precursor pulse. In some embodiments, each deposition cycle includes at least five alternating metal precursor pulses and inert gas purge pulses. In some embodiments, each deposition cycle includes at least ten alternating metal precursor pulses and inert gas purge pulses.

[0007] Other aspects of the present disclosure relate to a method for filling a structure with a metal-containing material, the method comprising preparing a structure to be filled with the metal-containing material and exposing the structure to multiple deposition cycles, each deposition cycle comprising multiple alternating hydrogen (H2) pulses followed by exposure to an inert gas pulse, and further exposure to a metal precursor pulse followed by an inert gas purge pulse. In some embodiments, the structure is a three-dimensional (3D) NAND structure in the process of being manufactured, which has side walls and a plurality of openings in the side walls, the openings leading to a plurality of features having a plurality of fluid-accessible internal regions through the openings. In some embodiments, the metal precursor is a chlorine-containing metal precursor. In some embodiments, the pulse of the chlorine-containing metal precursor contains between about 0.1% and about 5.0% of the chlorine-containing metal precursor by volume. In some embodiments, the exposure to multiple alternating H2 pulses and inert gas purge pulses includes turning off the inert gas purge flow during the metal precursor pulse. In some embodiments, each deposition cycle comprises only one metal precursor pulse. In other embodiments, each deposition cycle includes multiple alternating metal precursor pulses and inert gas pulses.

[0008] Other aspects of the present disclosure relate to an apparatus comprising one or more processing chambers, each configured to hold a substrate; one or more processing gas inlets for coupling to a hydrogen (H2) gas source, a metal precursor gas source, and an inert purge gas source; and a controller for controlling the operation of the apparatus, the controller including machine-readable instructions for performing multiple deposition cycles, each deposition cycle including injecting multiple alternating H2 pulses and inert gas purge pulses into one or more processing chambers via one or more purge gas inlets, and injecting a metal precursor pulse followed by an inert gas pulse. In some embodiments, the metal precursor is a chlorine-containing metal precursor. In some embodiments, the instructions include instructions for turning off the inert gas purge flow during the H2 pulse.

[0009] These and other aspects are further described below with reference to the drawings.

Brief Description of the Drawings

[0010] [Figure 1A] Figure 1A is a schematic diagram of an exemplary film on a substrate.

[0011] [Figure 1B] Figure 1B is a schematic example of various structures on which tungsten or molybdenum can be deposited according to some disclosed embodiments. [Figure 1C] Figure 1C is a schematic example of various structures on which tungsten or molybdenum can be deposited according to some disclosed embodiments. [Figure 1D] Figure 1D is a schematic example of various structures on which tungsten or molybdenum can be deposited according to some disclosed embodiments. [Figure 1E] Figure 1E is a schematic example of various structures on which tungsten or molybdenum can be deposited according to some disclosed embodiments. [Figure 1F] Figure 1F is a schematic example of various structures on which tungsten or molybdenum can be deposited according to some disclosed embodiments. [Figure 1G] Figure 1G is a schematic example of various structures on which tungsten or molybdenum can be deposited according to some disclosed embodiments. [Figure 1H] Figure 1H is a schematic example of various structures on which tungsten or molybdenum can be deposited according to some disclosed embodiments. [Figure 1I] Figure 1I is a schematic example of various structures on which tungsten or molybdenum can be deposited according to some disclosed embodiments. [Figure 1J] Figure 1J is a schematic example of various structures on which tungsten or molybdenum can be deposited according to some disclosed embodiments.

[0012] [Figure 2A]Figure 2A is a process flow diagram illustrating the operation of the method according to some of the disclosed embodiments. [Figure 2B] Figure 2B is a process flow diagram illustrating the operation of the method according to some of the disclosed embodiments. [Figure 2C] Figure 2C is a process flow diagram illustrating the operation of the method according to some of the disclosed embodiments.

[0013] [Figure 3] Figure 3 is a timing sequence diagram showing exemplary cycles in a method for depositing a film according to some of the disclosed embodiments.

[0014] [Figure 4A] Figure 4A is a schematic diagram of an example of a mechanism for depositing a film according to some of the disclosed embodiments. [Figure 4B] Figure 4B is a schematic diagram of an example of a mechanism for depositing a film according to some of the disclosed embodiments. [Figure 4C] Figure 4C is a schematic diagram of an example of a mechanism for depositing a film according to some of the disclosed embodiments. [Figure 4D] Figure 4D is a schematic diagram of an example of a mechanism for depositing a film according to some of the disclosed embodiments. [Figure 4E] Figure 4E is a schematic diagram of an example of a mechanism for depositing a film according to some of the disclosed embodiments. [Figure 4F] Figure 4F is a schematic diagram of an example of a mechanism for depositing a film according to some of the disclosed embodiments. [Figure 4G] Figure 4G is a schematic diagram of an example of a mechanism for depositing a film according to some of the disclosed embodiments. [Figure 4H] Figure 4H is a schematic diagram of an example of a mechanism for depositing a film according to some of the disclosed embodiments. [Figure 4I] Figure 4I is a schematic diagram of an example of a mechanism for depositing a film according to some of the disclosed embodiments. [Figure 4J] Figure 4J shows the film according to some of the disclosed embodiments.

[0015] [Figure 5] Figure 5 shows experimental results comparing tungsten packing in 3D NAND structures using the H2 / Ar / WClx / Ar sequence and the H2 / Ar / n(WClx / Ar) sequence.

[0016] [Figure 6] Figure 6 is a schematic diagram of an exemplary process tool for carrying out some of the disclosed embodiments.

[0017] [Figure 7] Figure 7 is a schematic diagram of an exemplary station for carrying out some of the disclosed embodiments.

[0018] [Figure 8] Figure 8 is a schematic diagram showing the basic features of a manifold system that may be used according to several embodiments. [Modes for carrying out the invention]

[0019] The following description includes various specific details to provide a complete understanding of the embodiments presented. The disclosed embodiments may be implemented without some or all of these specific details. On the other hand, well-known processes are not described in detail so as not to unnecessarily obscure the disclosed embodiments. While the disclosed embodiments are described in relation to specific embodiments, it should be understood that this does not limit the disclosed embodiments.

[0020] Tungsten (W) feature filling is commonly used in semiconductor device manufacturing to form electrical contacts. Conventional methods for depositing tungsten films involve first depositing a tungsten nucleation layer within a via or contact. Generally, the nucleation layer is a conformal thin layer that facilitates the subsequent formation of bulk material on top of it. The tungsten nucleation layer can be deposited to conformally cover the sidewalls and bottom of a feature. To support high-quality deposition, conformability to the bottom and sidewalls of the underlying feature can be crucial. The nucleation layer is often deposited using atomic layer deposition (ALD) or pulsed nucleation layer (PNL) methods.

[0021] In the PNL method, pulses of reactants are injected sequentially and typically purged from the reaction chamber by pulses of purge gas between reactants. The first reactant can be adsorbed onto the substrate and reacted with the next reactant. This process is repeated periodically until the desired thickness is achieved. The PNL method is similar to the ALD method. PNL is generally distinguished from ALD by its higher operating pressure range (greater than 1 Torr) and higher growth rate per cycle (more than 1 atomic layer of film growth per cycle). The chamber pressure during PNL deposition may be in the range of about 1 Torr to about 400 Torr. In the context of the description presented herein, PNL broadly embodies any periodic process of sequentially adding reactants for a reaction on a semiconductor substrate. Thus, this concept embodies the technique conventionally known as ALD. In the context of the disclosed embodiments, chemical vapor deposition (CVD) embodies a process in which reactants are introduced together into a reactor for a gas-phase or surface reaction. The PNL process and ALD process are different from the CVD process, and vice versa.

[0022] After depositing a tungsten nucleation layer, bulk tungsten is deposited, typically by a CVD process, by reducing tungsten hexafluoride (WF6) with a reducing agent such as hydrogen (H2). Bulk tungsten is distinct from the tungsten nucleation layer. As used herein, bulk tungsten refers to tungsten used to fill a large portion or all of a feature, such as at least about 50% of the feature. Unlike the nucleation layer, which is a conformal thin film that functions to facilitate the subsequent formation of bulk material on top of it, bulk tungsten is used to carry electric currents. It may be characterized by a larger particle size and lower resistivity compared to the nucleation layer. In various embodiments, bulk tungsten is tungsten deposited to a thickness of at least 50 Å.

[0023] As devices scale to finer technology nodes and more complex patterning structures are used, various challenges arise in tungsten filling. Conventional tungsten deposition involved the use of tungsten hexafluoride (WF6), a fluorine-containing precursor. However, the use of WF6 results in some fluorine being incorporated into the deposited tungsten film. The presence of fluorine can lead to electromigration and / or fluorine diffusion to adjacent components, as well as damage to contacts, thereby degrading device performance. One challenge is to reduce the fluorine content in the deposited tungsten film. The effect of a certain fluorine concentration becomes greater as the feature size decreases. This is because smaller features result in thinner films being deposited, and fluorine in the deposited tungsten film is more likely to diffuse through these thinner films.

[0024] One way to prevent fluorine diffusion is to deposit one or more barrier layers before depositing tungsten to prevent fluorine from diffusing from tungsten to other layers of the substrate, such as oxide layers. For example, Figure 1A shows an exemplary stack of layers deposited on a substrate. The substrate 190 includes a silicon layer 192, an oxide layer 194 (e.g., titanium oxide (TiOx), tetraethyl orthosilicate (TEOS) oxide, etc.), a barrier layer 196 (e.g., titanium nitride (TiN)), a tungsten nucleation layer 198, and a bulk tungsten layer 199. The barrier layer 196 is deposited to prevent fluorine diffusion from the bulk tungsten layer 199 and the tungsten nucleation layer 198 to the oxide layers. However, as the device shrinks, the barrier layers become thinner, and fluorine diffusion from the deposited tungsten layer is still possible. While chemical vapor deposition of bulktungsten at higher temperatures can reduce fluorine content, such films may have insufficient step coverage.

[0025] Another challenge is reducing stress in the deposited film. Thinner tungsten films tend to have greater tensile stress. Conventional techniques for depositing bulk tungsten films by chemical vapor deposition result in tensile stresses exceeding 2.5 GPa for a 200 Å film. High thermal tensile stress causes the substrate to curl, which makes subsequent processing difficult. For example, subsequent processes may include chemical mechanical planarization, material deposition, and / or clamping the substrate to a substrate holder to carry out the process in a chamber. However, these processes often rely on the substrate being flat, and a curled substrate results in uneven processing or makes it impossible to process the substrate. Although there are existing methods for reducing stress in films of other materials, such as annealing, tungsten, due to its high melting point, does not have the surface mobility to allow for particle movement or transformation after deposition.

[0026] To avoid such reliability and integration problems, or device performance issues, fluorine-free tungsten (FFW) precursors are useful. Current FFW precursors include organometallic precursors, but undesirable trace elements from organometallic precursors, such as carbon, hydrogen, nitrogen, and oxygen, can be incorporated into the tungsten film. In addition, some fluorine-free organometallic precursors are not easily implemented or integrated in tungsten deposition processes.

[0027] Some realizations described herein involve tungsten chloride (WCl x This invention relates to the deposition of tungsten using a tungsten precursor. Examples of tungsten chloride include tungsten pentachloride (WCl5), tungsten hexachloride (WCl6), tungsten tetrachloride (WCl4), tungsten dichloride (WCl2), and mixtures thereof. In the examples herein, WCl5 and WCl6 are given as examples, but it is understood that other tungsten chlorides may be used in the disclosed embodiments. The films deposited using some of the disclosed embodiments are fluorine-free. Some of the disclosed embodiments relate to the deposition of bulk tungsten using alternating pulses of chlorine-containing tungsten precursor and hydrogen.

[0028] Deposition with WCl5 and WCl6 presents challenges not present with WF6, due to the possibility of tungsten chloride erosion. Tungsten chloride, being less reactive, allows for higher temperatures than WF6 deposition. Evaporated WCl6 has a sufficiently high vapor pressure to be carried into the tungsten deposition chamber. However, WCl6 may be more likely to erode the substrate than WCl5. While WCl5 is less likely to erode the substrate, its vapor pressure is also higher than WCl6. Lower vapor pressure is useful for depositing tungsten films with low resistivity, but it may result in insufficient step coverage in some deposition operations.

[0029] Furthermore, the methods described herein may be used for the deposition of molybdenum (Mo) using a molybdenum chloride precursor or a molybdenum oxychloride precursor. Molybdenum may be used to form a low-resistance metallization stack structure and can be used as an alternative to tungsten.

[0030] The disclosed embodiments can be applied in a wide variety of ways. This method may be used to deposit tungsten or molybdenum within a feature with high step coverage, or it may be used to deposit tungsten within a 3D NAND structure.

[0031] The method described herein is carried out on a substrate that can be housed in a chamber. The substrate may be a silicon or other semiconductor wafer, for example, a 200 mm wafer, a 300 mm wafer, or a 450 mm wafer, and includes a wafer having one or more material layers deposited thereon, such as dielectric material, conductive material, or semiconductor material. The method is not limited to semiconductor substrates and may be carried out to fill any features with a metal such as tungsten.

[0032] The substrate may have features such as vias or contact holes, which may be characterized by one or more of the following: narrow and / or reentrant openings, constrictions within the feature, or high aspect ratios. Features may be formed in one or more of the layers described above. For example, features may be formed at least partially within a dielectric layer. In some embodiments, features may have aspect ratios of at least about 2:1, at least about 4:1, at least about 6:1, at least about 10:1, at least about 25:1, or even higher. An example of a feature is a hole or via in or within a layer on a semiconductor substrate.

[0033] Figures 1B–1H are schematic examples of various structures on which metal may be deposited according to the disclosed embodiments. Figure 1B shows an example of a cross-sectional view of a vertical feature 101 filled with a metal such as tungsten or molybdenum. The feature may include a feature hole 105 in a substrate 103. The hole 105 or other feature may have, for example, an aperture diameter or line width, as dimensions near the opening, between about 10 nm and 500 nm, for example between about 25 nm and 300 nm. The feature hole 105 may be called an unfilled feature, or simply a feature. Such a feature 101, and any feature, may be partially characterized by an axis 118 extending along the length of the feature, with vertically oriented features having a vertical axis and horizontally oriented features having a horizontal axis.

[0034] In some embodiments, the feature is a wordline feature within a 3D NAND structure. For example, the substrate may include a wordline structure having any number (e.g., 50 to 150) wordlines, along with vertical channels with a depth of at least 200 Å. Another example is a trench within the substrate or within a layer. The feature may be of any depth. In various embodiments, the feature may have an underlying layer, such as a barrier layer or adhesive layer. Non-limiting examples of underlying layers include dielectric and conductive layers, and include, for example, layers of silicon oxide, silicon nitride, silicon carbide, metal oxide, metal nitride, metal carbide, and metal.

[0035] Figure 1C shows an example of a feature 101 having a reentrant profile. A reentrant profile is a profile that narrows from the closed bottom edge or interior of the feature toward the feature opening. According to some realizations, the profile may be gradually narrowing and / or include an overhang on the feature opening. Figure 1C shows an example of the latter, where the sidewall or interior of the feature hole 105 is lined with an underlayer 113. The underlayer 113 can be, for example, a diffusion barrier layer, an adhesive layer, a nucleating layer, a combination thereof, or any other suitable material. Non-limiting examples of the underlayer can include dielectric and conductive layers, and can include, for example, layers of silicon oxide, silicon nitride, silicon carbide, metal oxide, metal nitride, metal carbide, and metal. In specific realizations, the underlayer can be one or more of titanium, titanium nitride, tungsten nitride, titanium aluminide, tungsten, and molybdenum. In some embodiments, the underlayer does not contain tungsten. In some embodiments, the underlayer does not contain molybdenum. The lower layer 113 forms an overhang 115, which makes the lower layer 113 thicker than the interior of feature 101 near the opening of feature 101.

[0036] In some implementations, features with one or more constrictions within them may be filled. Figure 1D shows examples of figures where various features with constrictions are filled. Examples (a), (b), and (c) in Figure 1D each contain a constriction 109 at a midpoint within the feature. The constriction 109 may have a width, for example, between approximately 15 nm and 20 nm. When tungsten or molybdenum is deposited into a feature using conventional techniques, the deposited metal can obstruct the deposit beyond the constriction before that portion of the feature is filled, causing the constriction to become a pinch-off point, resulting in voids within the feature. Example (b) further includes a liner / barrier overhang 115 in the feature opening. Such an overhang can also potentially become a pinch-off point. Example (c) includes a constriction 112 further away from the field region than the overhang 115 in Example (b).

[0037] Furthermore, horizontal features, such as those found in 3D memory structures, can also be filled in. Figure 1E shows an example of a horizontal feature 150 including a constriction 151. For example, the horizontal feature 150 could be a word line in a 3D NAND structure. In some realizations, the constriction may be due to the presence of pillars in the 3D NAND or other structures. For example, Figure 1F shows a side section of a 3D NAND (also called vertical NAND, or VNAND) structure 110 (formed on a semiconductor substrate 103), which has a VNAND stack (left side 125 and right side 126), a central vertical structure 130, and a plurality of horizontal features 120 stacked on the opposing side walls 140 of the central vertical structure 130 with openings 122. Note that while Figure 1F shows two stacks that together form a trench-like central vertical structure 130 of the presented 3D NAND structure 110, in some embodiments, more than two stacks may be arranged in a sequence, extending spatially parallel to one another. In this case, the gaps between each pair of adjacent stacks form the central vertical structure 130 as shown in Figure 1F. In this embodiment, the horizontal feature 120 is a 3D memory word line feature that is fluidly accessible from the central vertical structure 130 through an opening 122. Although not shown in the drawing, the horizontal feature 120 within both 3D NAND stacks 125 and 126 shown in Figure 1F (i.e., the left 3D NAND stack 125 and the right 3D NAND stack 126) is also accessible from the other side of the stack (the leftmost and rightmost sides, respectively) through similar vertical structures formed by additional 3D NAND stacks (not shown, but slightly to the left and slightly to the right). In other words, each 3D NAND stack 125, 126 includes a stack of word line features that are fluidly accessible from both sides of the 3D NAND stack through a central vertical structure 130. In the specific example schematically shown in Figure 1F, each 3D NAND stack includes six pairs of stacked word lines, but in other embodiments, the 3D NAND memory layout may include any number of vertically stacked word line pairs.

[0038] Word line features in a 3D NAND stack are typically formed by depositing stacks of alternating silicon oxide and silicon nitride layers, and then selectively removing the nitride layers, leaving stacks of oxide layers with gaps in between. These gaps are the word line features. Any number of word lines can be vertically stacked within such a 3D NAND structure, provided that there are available techniques for forming word lines and for successfully achieving (mostly) void-free filling of vertical features. Thus, for example, a VNAND stack may contain between 2 and 256 horizontal word line features, or between 8 and 128 horizontal word line features, or between 16 and 64 horizontal word line features, etc. (the listed ranges are understood to include the endpoints described).

[0039] Figure 1G presents a horizontal cross-sectional view of the same 3D NAND structure 110 shown in the side view in Figure 1F, with a cross-section of a horizontal section 160 as shown by the horizontal dashed line in Figure 1F. The cross-section in Figure 1G shows several rows of pillars 155, which are shown in Figure 1F to extend vertically from the base point of the semiconductor substrate 103 to the top of the 3D NAND stack 110. In some embodiments, these pillars 155 are formed of polysilicon material and are structurally and functionally important to the 3D NAND structure 110. In some embodiments, such polysilicon pillars may function as gate electrodes of stacked memory cells formed within those pillars. The plan view in Figure 1G shows that the pillars 155 form a constriction at the opening 122 to the wordline feature 120, i.e., the possibility of fluid access from the central vertical structure 130 to the wordline feature 120 through the opening 122 (as shown by the arrow in Figure 1G) is obstructed by the pillars 155. In some embodiments, the size of the horizontal gap between adjacent polysilicon pillars is between approximately 1 and 20 nm. This reduced fluid accessibility increases the difficulty of uniformly filling the wordline features 120 with tungsten material. The structure of the wordline features 1 and the difficulty of uniformly filling them with tungsten or molybdenum material due to the presence of pillars 155 are further illustrated in Figures 1H, 1I, and 1J.

[0040] Figure 1H shows a vertical cross-section of a 3D NAND structure similar to that shown in Figure 1F, except that it focuses only on a pair of wordline features 120 and schematically illustrates the metal filling process that results in the formation of voids 175 in the wordline features 120 after filling. Voids 175 are also schematically shown in Figure 1I, however, in this figure they are shown by a horizontal cross-section of the pillar 155, similar to the horizontal cross-section shown in Figure 1G. Figure 1J shows the accumulation of tungsten or molybdenum material around the constricting pillar 155, and as a result of this accumulation, a pinch-off of the opening 122 occurs, preventing the deposition of further tungsten or molybdenum material in the area of ​​void 175. As is evident from Figures 1H and 1I, void-free tungsten or molybdenum filling relies on a sufficient amount of deposited precursor moving through the vertical structure 130, through the opening 122, past the constricting pillar 155, and to the deepest part of the wordline feature 120 before tungsten accumulates around pillar 155, causing pinch-off of the opening 122 and preventing further precursor movement into the wordline feature 120. Similarly, Figure 1J presents only one wordline feature 120 viewed in section from above, showing how pinch-off begins inside the wordline feature 120 due to the generally conformal deposition of tungsten or molybdenum material, which causes a considerable width of pillar 155 to partially block and / or narrow and / or constrict what would otherwise be an open passage penetrating the wordline feature 120. (It should be noted that the example in Figure 1J can be understood as a 2D rendering of the 3D features of the pillar constriction structure shown in Figure 1I, and therefore it shows the constriction as it would appear in a plan view, not a cross-sectional view.)

[0041] The three-dimensional structure may require longer and / or more intensive exposure of the precursor to enable filling of the deepest regions. The three-dimensional structure is WCl xWhen using precursors, the tendency for erosion can be particularly challenging, as longer and more intensive exposure may lead to greater erosion in certain parts of the structure. These challenges may also exist in the case of molybdenum chloride precursors.

[0042] Examples of feature filling for horizontal and vertical features are described below. It should be noted that these examples are often applicable to both horizontal and vertical features. Furthermore, it should be noted that in the following descriptions, the term "horizontal" may refer to a direction approximately perpendicular to the feature axis, and the term "vertical" may refer to a direction approximately aligned with the feature axis.

[0043] In various embodiments, the method described below involves exposing the structure to multiple reducing agent / purge cycles and / or multiple metal precursor / purge cycles within a single ALD cycle. In some implementations, one or more of the following advantages may be realized. In some embodiments, multiple tungsten-containing precursor doses (e.g., W / Ar / W / Ar / W / Ar / W / Ar, where W represents a pulse of tungsten-containing precursor and Ar represents a pulse of argon purge gas) with purge gas pulses in between make it possible to deliver the tungsten-containing precursor deep into the 3D NAND wordline structure or other structures that are difficult to fill. In some implementations, one or more of the following advantages may be realized. In some embodiments, multiple doses of molybdenum-containing precursor (e.g., Mo / Ar / Mo / Ar / Mo / Ar / Mo / Ar, where Mo represents the pulse of the molybdenum-containing precursor and Ar represents the pulse of the argon purge gas) interspersed with purge gas pulses make it possible to deliver the molybdenum-containing precursor deep into 3D NAND wordline structures or other structures that are difficult to fill.

[0044] An inert gas purge pulse following each metal-containing pulse ensures that one atomic layer of the metal-containing precursor is adsorbed throughout the structure. In some embodiments, multiple pulses of purge gas following each pulse ensure that multiple atomic layers of the metal-containing precursor do not accumulate in more accessible parts of the structure. This prevents undesirable erosion of the structure. In some embodiments, alternating pulses allow for pressurization of the metal precursor tank before each pulse. This can promote flux to the bottom of the feature. In some embodiments, multiple reducing agent dose pulses interspersed with purge gas pulses (for example, H2 / Ar / H2 / Ar / W / Ar / W / Ar, where H2 is the reducing agent, W represents the pulse of the tungsten-containing precursor, and Ar represents the pulse of the argon purge gas, or H2 / Ar / H2 / Ar / Mo / Ar / Mo / Ar, where Mo represents the pulse of the molybdenum-containing precursor) provide sufficient time for the adsorbed chloride and the reducing agent to react, and allow the reaction product (e.g., HCl) to detach from the surface, making space for the reducing agent in the next pulse.

[0045] While the following description focuses on tungsten and molybdenum feature filling, embodiments of this disclosure may be implemented for feature filling with other materials. For example, feature filling using one or more techniques described herein may be used to fill features with other materials, such as other tungsten-containing materials (e.g., tungsten nitride (WN), tungsten carbide (WC)), titanium-containing materials (e.g., titanium (Ti), titanium nitride (TiN), titanium silicide (TiSi), titanium carbide (TiC), titanium aluminide (TiAl)), tantalum-containing materials (e.g., tantalum (Ta), tantalum nitride (TaN)), and nickel-containing materials (e.g., nickel (Ni), nickel silicide (NiSi)). Furthermore, the methods and apparatus disclosed herein are not limited to feature filling and can be used to deposit tungsten on any suitable surface, such as to form a blanket film on a flat surface.

[0046] Figures 2A-2C show process flow diagrams of a method implemented according to the disclosed embodiments. As described below, this method is implemented to fill a structure on a substrate with tungsten. Examples of structures are described above with reference to Figures 1B-1H.

[0047] The temperature may vary depending on the chemical substance used. x and WO x In the case of the Cl4 precursor, some of the disclosed embodiments may be carried out at a substrate temperature between approximately 400°C and approximately 600°C, such as approximately 525°C. The substrate temperature refers to the temperature set by the pedestal that holds the substrate.

[0048] MoCl x and MoO x Cl y In the case of precursors, some of the disclosed embodiments may be carried out at substrate temperatures between approximately 400°C and approximately 600°C, such as approximately 525°C. Substrate temperature refers to the temperature set by the pedestal that holds the substrate.

[0049] Some of the disclosed embodiments may be carried out at chamber pressures between approximately 3 Torr and approximately 60 Torr. In some embodiments, WCl x In the case of tungsten deposition using a precursor, the chamber pressure is between 5 Torr and 20 Torr, for example, 10 Torr.

[0050] Referring to Figure 2A, in Operation 200, the structure to be filled with tungsten or molybdenum is exposed to a reducing agent pulse. In some embodiments, the reducing agent pulse is hydrogen (H2). Other reducing agents may be used, such as silane, borane, Germane, phosphine, hydrogen-containing gases, and combinations thereof. In various embodiments, bulk tungsten deposition or bulk molybdenum deposition is carried out using hydrogen as the reducing agent. The reducing agent is pulsed without introducing other reactants. In some embodiments, a carrier gas may be introduced. In some embodiments, a carrier gas such as nitrogen (N2), argon (Ar), helium (He), or other inert gases may be introduced in Operation 200.

[0051] Operation 200 may be performed for any appropriate duration. Examples of durations include those between approximately 0.25 seconds and 30 seconds, between approximately 0.25 seconds and 20 seconds, between approximately 0.25 seconds and 5 seconds, or between approximately 0.5 seconds and 3 seconds.

[0052] In Operation 202, the chamber is purged to remove any excess hydrogen that was not adsorbed on the substrate surface. The purging may be performed by lowering the pressure in the chamber by introducing an inert gas at a constant pressure, and then repressurizing the chamber before initiating exposure to another reaction gas. Examples of inert gases include nitrogen (N2), argon (Ar), helium (He), and mixtures thereof. The purging may be performed for a duration of approximately 0.25 to 30 seconds, approximately 0.25 to 20 seconds, approximately 0.25 to 5 seconds, or approximately 0.5 to 3 seconds.

[0053] Next, operations 200 and 202 are repeated until they are executed k times, where k is an integer of at least 21. In one example, the duration of operation 200 may be 0.5 seconds, and the duration of operation 202 between pulses of the reducing agent may be 1 second. When k = 10, the total time of the tungsten precursor is 0.5 × 10 = 5 seconds, and the total time of the purge is 1 × 10 = 10 seconds.

[0054] In operation 204, the substrate is exposed to a tungsten precursor or a molybdenum precursor. Examples of precursors include chlorine-containing tungsten precursors such as tungsten chloride and tungsten oxychloride. Assuming x is an integer between 2 and 6, including 2 and 6, such as 2, 3, 4, 5, or 6, tungsten chloride can be WCl x x. For example, WCl5 and WCl6 are included. The chlorine-containing tungsten precursor can include a mixture of WCl x compounds. Assuming x and y are numbers greater than 0, tungsten oxychloride is WO x Cl y y. To deposit molybdenum, molybdenum precursors such as molybdenum chloride and molybdenum oxychloride are used. These include molybdenum pentachloride (MoCl5), molybdenum dioxide dichloride (MoO2Cl2), and molybdenum oxychloride tetrachloride (MoOCl4).

[0055] In some embodiments, in operation 206, a carrier gas such as nitrogen (N2), argon (Ar), helium (He), or another inert gas may be flowed in.

[0056] Operation 204 may be performed at any suitable temperature for any suitable duration. In some examples, Operation 206 may be performed for a duration between approximately 0.25 seconds and approximately 30 seconds, between approximately 0.25 seconds and approximately 20 seconds, between approximately 0.25 seconds and approximately 5 seconds, or between approximately 0.5 seconds and approximately 3 seconds. In some embodiments, this operation may be performed for a duration sufficient to saturate the active sites on the substrate surface. In some embodiments, the precursor may be diverted for gas line filling and line changes before dose. The carrier gas may be any of those described above with respect to Operation 202.

[0057] According to various embodiments, in operation 204, some WCl x However, it may react with H2 remaining on the surface from Operation 200, and some WCl x It may not react completely with the H2 remaining on the surface. Also, in various embodiments, some H2 is absorbed by WCl x And sometimes there is no reaction at all, WCl x Instead, H2 can be physically adsorbed onto the substrate surface or, in the case of no H2 remaining on the substrate surface, it can be physically adsorbed onto the substrate surface. In some embodiments, H2 may remain on the substrate surface but not be physically or chemically adsorbed onto the surface. Operation 204 in Figure 2A can thereby form a subatomic layer of tungsten in some embodiments. Similarly, Operation 204 can form a subatomic layer of molybdenum in some embodiments.

[0058] Operation 206 involves purging to remove any excess precursor that remains in the gaseous phase and has not reacted with hydrogen or other reducing agents on the feature's surface. The purging may be performed by reducing the pressure in the chamber by introducing an inert gas at a constant pressure, and then repressurizing the chamber before initiating exposure to another gas.

[0059] The chamber may be purged for any appropriate duration. The chamber may be purged for a duration between approximately 0.25 seconds and approximately 30 seconds, between approximately 0.25 seconds and approximately 20 seconds, between approximately 0.25 seconds and approximately 5 seconds, or between approximately 0.5 seconds and approximately 3 seconds. In some embodiments, the purge duration is between approximately 0.1 seconds and approximately 2 seconds, which, according to this purge duration, allows WCl to reach the tungsten surface. x Due to the low adsorption rate, WCl x Alternatively, it is possible to avoid the removal of all other precursors. In some embodiments, the purge duration is between about 0.1 seconds and about 15 seconds, for example, about 7 seconds. For example, in the case of manufacturing a 3D NAND structure, the chamber may be purged for about 2 seconds in operation 206. The purge gas may be any of the gases described above in relation to operation 202.

[0060] Next, operations 204 and 206 are repeated until they have been performed n times, where n is an integer at least 2. As will be further explained below, performing multiple tungsten pulses separated by purging in the deposition sequence can reduce undesirable erosion at the tops and edges of the structure. In one example, the duration of operation 204 may be 0.7 seconds, and the duration of operation 206 between tungsten precursor pulses may be 2 seconds. When n=10, the total tungsten precursor time is 0.7 × 10 = 7 seconds, and the total purging time is 2 × 10 = 20 seconds.

[0061] Operation 208 determines whether the tungsten or molybdenum layer has been deposited to the appropriate thickness. If not, operations 200–206 are repeated until a tungsten or molybdenum layer of the desired thickness is deposited on the feature surface. Each iteration of operations 200–206 is sometimes referred to as a “cycle”. In some embodiments, the order of operations 200 / 202 and 204 / 206 may be reversed to introduce the tungsten or molybdenum precursor before introducing the reducing agent.

[0062] Figure 2B shows a process flow diagram for an embodiment in which operations 200 and 202 are not repeated during a cycle, by including only one reducing agent pulse and multiple tungsten precursor pulses or molybdenum precursor pulses in each ALD cycle. Figure 2C shows a process flow diagram for an embodiment in which operations 204 and 206 are not repeated during a cycle, by including only one tungsten precursor pulse or molybdenum precursor pulse and multiple reducing agent pulses in each ALD cycle. The process blocks in Figures 2B and 2C are otherwise the same as described above with respect to Figure 2A.

[0063] Figure 3 shows H2 and WCl x The timing sequence diagrams show exemplary deposition cycles 311A ​​and 311B in the process of depositing tungsten using [a specific method]. Figure 3 shows the H2 pulse in deposition cycle 311A, which is an example of an embodiment of operation 200 in Figures 2A-2C. In the example in Figure 3, during the H2 pulse, Ar flow and WCl x The flow is turned off. In other embodiments, the inflow of purge gas may be continued during the reducing agent pulse. In some embodiments, turning off the purge gas during the reducing agent pulse is effective in increasing exposure to the reducing agent. An Ar pulse is shown immediately after H2. This is an example of an embodiment of operation 202 in Figures 2A-2C. During the purge pulse, the H2 flow and WCl x Turn off the flow. A dotted box in reference numeral 320 indicates any number of H2 pulses / Ar purge pulses, in this case, executed without intervening tungsten precursor pulses. This is an example of embodiments of operations 200 and 202 in Figures 2A and 2C. Five H2 / Ar pulse sequences are shown, but the number of H2 / Ar pulse sequences can be in the range of 1 to k as described above. A dotted box in reference numeral 340 indicates repeated WCl xThis shows pulses / Ar purge pulses, in which case they are executed without a reducing agent pulse in between. This is an example of an embodiment of operations 204 and 206 in Figures 2A and 2B. WCl x During the pulse, the Ar valve is closed, and during the Ar pulse, WCl x The valve is closed. The hydrogen flow is turned off throughout this process. 4 WCl x The / Ar pulse sequence is shown, but the number of H2 / Ar pulse sequences can be in the range of 1 to n, as mentioned above.

[0064] It should be noted that in some embodiments, H2 pulse and / or WCl x During the pulse, the Ar flow can remain on, and in this case, the H2 flow and WCl flow can also remain on. x An AR pulse characterized by the absence of flow is used, and in some embodiments, an increased Ar flow is also used. However, during the tungsten precursor pulse, it may be effective to turn off the purge gas to avoid further dilution of the tungsten precursor gas (which may be supplied diluted). A higher W concentration on the wafer is effective for filling the 3D NAND structure, and if it is diluted, the resulting filling will be insufficient. Furthermore, by turning off the purge gas and pressurizing the purge manifold during the tungsten precursor pulse, more efficient purging of the chamber is possible than continuing the purge flow with W pulses in between. Similarly, during the reducing agent pulse, it may be effective to turn off the purge gas to avoid dilution of the reducing agent gas. As shown in Figure 3, the deposition cycle 311A ​​is terminated by an Ar pulse.

[0065] The example in Figure 3 is WCl for illustrative purposes. xAlthough this is shown, the timing sequence in Figure 3 may be used for other precursors, such as tungsten oxychloride precursors and molybdenum chloride precursors. Similarly, other purge gases and / or other reducing agents may be used instead of Ar and H2.

[0066] The processes described in Figures 2A-2C and the pulse sequences explained with reference to Figure 3 are examples of pulse sequences. Those skilled in the art will understand that various modifications are possible. For example, in some embodiments, different purge gases may be used, as described above. Similarly, while the described process is particularly useful for chlorine-containing tungsten or molybdenum precursors, which tend to erode the substrate at high concentrations, this process may also be used when filling structures with other precursors and materials, such as fluorine-containing W and Mo precursors. In particular, this process may be effective for filling high aspect ratio and / or three-dimensional structures.

[0067] Figures 4A–4J are schematic diagrams illustrating exemplary mechanisms of the deposition cycle in tungsten deposition from WCl6. Figure 4A shows an exemplary mechanism for incorporating H2 into a substrate 400 on which an underlying layer 401 is deposited. The underlying layer 401 may be a barrier layer in some embodiments. For example, in some embodiments, the underlying layer 401 is a titanium nitride (TiN) layer. It should be noted that in some embodiments, the substrate 400 does not contain a tungsten nucleating layer. In other embodiments, it may contain a tungsten nucleating layer. Hydrogen is introduced in the gas phase (411a and 411b), and some H2 (413a and 413b) is on the surface of the underlying layer 401, in which case the hydrogen may catalytically dissociate into chemically active adsorbed hydrogen atoms on a metal surface (e.g., H2) or physically adsorb onto a non-catalytic surface (e.g., TiN). For example, H2 may not necessarily be chemically adsorbed onto the lower layer 401, but in some embodiments, it may be physically adsorbed onto the surface of the lower layer 401.

[0068] Figure 4B shows an example where H2 (411a and 411b in Figure 4A), which was previously in the gas phase, is purged from the chamber, and H2 (443a and 413b), which was previously on the surface, remains on the surface of the lower layer 401.

[0069] Figure 4C presents a schematic example showing that the substrate is exposed to WCl6, with some of the WCl6 being in the gas phase (431a and 431b) and some of the WCl6 being on or near the surface of the substrate (423a and 423b).

[0070] In Operation 200, some H2 may react with WCl6 remaining on the surface from the previous dose. In Figure 4D, the reaction of WCl6 with H2 temporarily forms intermediate 443b, which in Figure 4E completes with the reaction of intermediate 443b, leaving tungsten 490 on the substrate 401 surface, with HCl remaining in the gas phase (e.g., 451a and 451b). In this example, it should be noted that tungsten 490 is grown directly on the substrate 401 without depositing a nucleating layer and without treating the substrate 401 before depositing the tungsten. In some embodiments, it will be understood that the substrate 401 may be soaked, for example by exposure to diborane, before being exposed to a hydrogen or chlorine-containing tungsten precursor. In some examples, the substrate 401 is later treated with WCl x The Si-BH interface layer may be pre-treated with a mixture of SiH4, B2H6, and H2 to form a solid Si-BH interface layer capable of sacrificial reactions upon exposure to H2. The stoichiometric composition of the Si-BH layer can vary considerably, from low (10%) boron concentrations to high (95%) boron concentrations.

[0071] In operation 200 shown in Figures 2A-2C, some H2 may not fully react with the WCl6 (or other tungsten chloride) remaining on the surface from the previous dose. As shown in Figure 4D, the partial reaction of WCl6 with H2 forms intermediate 443a, which in turn remains partially reacted on the substrate 400 above the underlying layer 401 in Figure 4E. In various embodiments, films deposited using chlorine-containing tungsten precursors and hydrogen have lower resistivity than films deposited using borane, silane, or Germanine, when the deposition thickness is up to approximately 50 Å. For example, without being bound by any particular theory, the stoichiometry of WCl6 suggests that at least three H2 molecules can react with one WCl6 molecule. WCl6 may partially react with H2 molecules to form an intermediate rather than forming tungsten. For example, this can occur when there are not enough H2 molecules nearby to react with WCl6, based on the principle of stoichiometry (e.g., three H2 molecules react with one WCl6 molecule), resulting in the presence of intermediate 343a on the substrate surface. Tungsten chloride may be chemically inert to H2 molecules and may require the presence of adsorbed hydrogen atoms produced by the catalytic dissociation of H2 molecules. In this case, a number of H2 molecules far exceeding the simple stoichiometric ratio may be required to completely reduce tungsten chloride to metallic tungsten (100:1 H2 molecules / WCl). x ratio).

[0072] Figure 4F shows a schematic example of the substrate when the chamber is purged. This may correspond to operation 202 in Figures 2A-2C. It should be noted that compound 443c in Figure 4F may be an intermediate formed without complete reaction, while some tungsten 490 may be formed on the substrate. Each cycle thereby forms a subatomic layer of tungsten on the substrate.

[0073] As an example, Figure 4G shows the result of repeating the cycle, in which gas-phase H2411c is incorporated into the substrate having deposited tungsten 490 and a partially reacted intermediate 443d on top of it. This may correspond to operation 200 in Figures 2A-2C in the repeated cycle after it is determined in operation 208 that the tungsten has not been deposited to the appropriate thickness. As shown in Figure 4G, it should be noted that the incorporated H2 can now completely react with the intermediate 443d on the substrate, and as shown in Figure 4H, the reacted compound 443d leaves the deposited tungsten 490b and 490c behind, and the by-products HCl 451c and 451d are formed in the gas phase. Some H2411c may remain in the gas phase, while some H2413c may remain on top of the tungsten layer 490a.

[0074] In Figure 4I, the chamber is purged (corresponding to operation 202 in Figures 2A-2C), leaving behind the deposited tungsten molecules 490a, 490b, and 490c, along with some H2413c. In Figure 4J, WCl6 is again introduced in dose, at which point molecules 431c and 423c may adsorb and / or react with H2 and the substrate. Figure 4J may correspond to operation 204 in Figures 2A-2C. After the WCl6 dose, the chamber may be purged again, and the cycle may be repeated until tungsten of the desired thickness is deposited.

[0075] Tungsten films deposited using some of the disclosed embodiments are fluorine-free. Molybdenum films may also be fluorine-free. The tensile stress of the entire film may be less than about 0.2 GPa. As fluorine-free tungsten precursors, carbonyl tungsten (W(CO)6) and tungsten chloride (WCl) such as tungsten pentachloride (WCl5) and tungsten hexachloride (WCl6) are used. x ) may include. Fluorine-free molybdenum precursors include the oxymolybdenum chloride precursors and molybdenum chloride precursors described herein, as well as hexacarbonylmolybdenum (Mo(CO)6).

[0076] The disclosed embodiments may be applied in various ways to tungsten and molybdenum deposition processes. Various combinations of the applications described herein may be used to deposit tungsten or molybdenum, and it will be understood that these methods are not limited to the examples presented herein.

[0077] For example, in some embodiments, a tungsten nucleating layer may be deposited by an ALD cycle of alternating pulses of a reducing agent (e.g., borane, silane, or germane with hydrogen) and a tungsten precursor such as WCl6, and then the feature may be filled by depositing bulk tungsten by alternating pulses of hydrogen and a chlorine-containing tungsten precursor, as described above with respect to Figures 2 and 3. Similarly, in some embodiments, the feature may be filled by depositing a molybdenum layer by an ALD cycle of alternating pulses of a reducing agent and a molybdenum precursor. The deposition of bulk tungsten by a process using alternating pulses of a tungsten chloride precursor and a reducing agent such as hydrogen is sometimes called an ALD process because it involves alternating pulses of reactants. The methods described herein typically involve purging between reactant cycles to ensure that there are no growing components from the CVD mechanism.

[0078] On the other hand, in some embodiments, these methods may be used in conjunction with “sequential CVD” processes such as those described in U.S. Patent Application Publication No. 2017 / 0117155 and U.S. Patent No. 9613818, both of which are incorporated herein by reference.

[0079] By employing multiple cycles of alternating precursor pulses and purge gas pulses within a single deposition cycle, the precursor can be delivered deep into the 3D NAND wordline while minimizing erosion at the top and lateral edges of the structure. A single atomic layer or subatomic layer of the precursor can be adsorbed across the entire structure. In some embodiments, the use of alternating precursor pulses and purge pulses allows for pressurization of the precursor tank before the delivery of the precursor dose. As a result, the precursor can be delivered more effectively into the structure.

[0080] Table 1 shows the H2 / Ar / WCl ratio for n=10. x / Ar sequence and H2 / Ar / n(WCl x This shows the conditions and resulting erosion of the TiN sublayer for a 300 Å PVD TiN blanket membrane exposed to the / Ar) sequence. [Table 1] The conditions and results in Table 1 show that, given the same total exposure to the tungsten precursor, the amount of TiN eroded by multiple pulses of the tungsten precursor is significantly less. In particular, in the case of a sequence using a single tungsten precursor pulse, all of the TiN was eroded.

[0081] Figure 5 shows H2 / Ar / WCl x When using the / Ar sequence, and H2 / Ar / n(WCl x This diagram shows a schematic representation of experimental results comparing tungsten packing in 3D NAND structures using the H2 / Ar / WCl sequence. A nucleation layer was deposited within each structure prior to these sequences. Figure 5 shows a cross-section of the central section of the 3D NAND structure. 3D NAND structure 503 is H2 / Ar / WCl x This image was taken after the / Ar sequence and shows insufficient tungsten deposition in the central word line, as shown in 511. With n=10, H2 / Ar / n(WCl) xWhen the 3D NAND structure 503 was exposed to Ar, a uniform tungsten deposition was observed throughout it. The total exposure to the tungsten precursor in toll-seconds was the same for both 501 and 503.

[0082] Each of the n tungsten pulses is short in duration and may be supplied at a constant pressure. The total amount of tungsten precursor is sufficient to supply enough material for the tungsten precursor to reach the bottom of the structure and to coat the entire structure laterally. Intermediate inert gas purging may remove the tungsten precursor from the top and edges of the structure, reducing or eliminating substrate erosion. If the inert gas purging is insufficient, this beneficial effect may not be observed. Furthermore, if purging between multiple tungsten pulses is insufficient, a pinch effect may be observed around the opening.

[0083] Therefore, in some embodiments, the duration of the inert gas purge is at least the same as the duration of the tungsten precursor or molybdenum precursor. In some embodiments, the duration of the inert gas purge is at least 1.5 times, at least 2 times, or at least 3 times the duration of the tungsten precursor pulse or molybdenum precursor pulse. The exposure of the precursor to the purge gas may also be characterized by partial pressure × duration. The precursor may be diluted to 1% to 5% of the flow rate, while the purge may be performed using 100% purge gas.

[0084] While the above description focuses on the deposition of tungsten layers and tungsten-containing layers from tungsten chloride, the process described above may be carried out with feature filling using other precursors and / or other materials, referring to Figures 2 and 3. As mentioned above, this method is effective in the case of chemicals that may erode the structure. Furthermore, methods involving multiple precursor pulse / purge cycles may be effective in obtaining growth without CVD-type characteristics by purging unadsorbed molecules.

[0085] The disclosed embodiments may be carried out at any appropriate pressure, such as a pressure greater than about 10 Torre or a pressure less than about 10 Torre. In the case of a multi-station chamber, each pedestal may be set to a different temperature. In some embodiments, each pedestal is set to the same temperature. During some or all of the operations described above according to the disclosed embodiments, the substrate may be circulated from station to station. Also, in one or more operations in some of the disclosed embodiments, the chamber pressure may be modulated. In some embodiments, the chamber pressure during nucleation deposition is different from the chamber pressure during bulk deposition. In some embodiments, the chamber pressure during nucleation deposition is the same as the chamber pressure during bulk deposition.

[0086] [Device] Any suitable chamber may be used to carry out the disclosed embodiments. Examples of deposition systems include a variety of systems, such as ALTUS® and ALTUS® Max, available from Lam Research Corp. in Fremont, California, or any of a variety of other commercially available processing systems. In some embodiments, sequential chemical vapor deposition (CVD) may be carried out in a first station, which is one of two, five, or more deposition stations arranged in a single deposition chamber. In this case, hydrogen (H2) and tungsten hexachloride (WCl6), for example, may be introduced into the surface of the semiconductor substrate in alternating pulses using individual gas supply systems that create a local atmosphere on the substrate surface. Other stations may be used for fluorine-free tungsten deposition or CVD. Two or more stations may be used to deposit tungsten in parallel. Alternatively, wafers may be indexed so that sequential CVD operations are performed sequentially across two or more stations.

[0087] Figure 6 is a schematic diagram of a processing system suitable for carrying out a deposition process according to several embodiments. System 600 comprises a transport module 603. The transport module 603 provides a clean pressurized environment to minimize the risk of substrate contamination when transporting the substrate being processed between various reactor modules. A multi-station reactor 609 capable of carrying out ALD and CVD according to various embodiments is attached to the transport module 603. The multi-station reactor 609 may have a number of stations 611, 613, 615, and 617 that can sequentially perform operations according to the disclosed embodiments. For example, the multi-station reactor 609 may be configured to carry out tungsten nucleation layer deposition by PNL using a chlorine-containing tungsten precursor or a fluorine-containing precursor at station 611, and to carry out tungsten deposition operations by ALD according to various embodiments at station 613. In some embodiments, tungsten deposition operations by ALD may also be carried out at station 615, and non-sequential CVD operations may be carried out at station 617. In some embodiments, the number (n) of tungsten precursor pulses may vary depending on stations 613-615.

[0088] These stations may have a heated pedestal or substrate support and one or more gas inlets or showerheads or dispersion plates. An example of a deposition station 700 is shown in Figure 7, which has a substrate support 702 and a showerhead 703. A heater may be provided in the pedestal section 701.

[0089] Referring again to Figure 6, one or more single or multi-station modules 607 capable of performing plasma or chemical (non-plasma) pre-cleaning, other deposition operations, or etching operations may be attached to the transport module 503. These modules may also be used for various processes, for example, to prepare substrates for deposition processes. The system 600 further includes one or more wafer source modules 601 for storing wafers before and after processing. First, wafers may be removed from the source modules 601 to the load lock 621 by an atmospheric robot (not shown) in an atmospheric transport chamber 619. Wafer transport devices (typically robotic arm units) in the transport module 603 transport the wafers from the load lock 621 to modules attached to the transport module 603, and between modules attached to the transport module 603.

[0090] In various embodiments, a system controller 629 is employed to control process conditions during deposition. The controller 629 typically comprises one or more memory devices and one or more processors. The processors may include a CPU or computer, analog and / or digital input / output connections, a stepping motor controller board, and the like.

[0091] The controller 629 can control all aspects of the operation of the deposition apparatus. The system controller 629 runs system control software that includes an instruction set for controlling the timing of a particular process, gas mixing, chamber pressure, chamber temperature, wafer temperature, radio frequency (RF) power level, wafer chuck or pedestal position, and other parameters. In some embodiments, other computer programs stored in a memory device associated with the controller 629 may be employed.

[0092] Typically, a user interface is provided associated with the controller 629. The user interface may include a display screen, a graphical software display of the device and / or process conditions, and further, user input devices such as a pointing device, keyboard, touchscreen, or microphone.

[0093] System control logic may be configured in any suitable manner. Generally, logic can be designed or configured in hardware and / or software. Instructions for controlling drive circuits may be hardcoded or provided as software. These instructions may be provided by “programming.” Such programming is understood to include any form of logic, such as hardcoded logic in digital signal processors, application-specific integrated circuits, and other devices, which have specific algorithms implemented in hardware. Programming is further understood to include software or firmware instructions that can be executed on a general-purpose processor. System control software may be coded in any suitable computer-readable programming language.

[0094] Computer program code for controlling the germanium-containing reducing agent pulse, hydrogen flow, and tungsten-containing precursor pulse, as well as other processes in the process sequence, can be written in any of the common computer-readable programming languages, such as assembly language, C, C++, Pascal, or Fortran. The tasks indicated by the program are performed by executing the compiled object code or script on a processor. Furthermore, as mentioned above, the program code may be hardcoded.

[0095] Controller parameters relate to process conditions such as the composition and flow rate of the processing gas, temperature, pressure, cooling gas pressure, substrate temperature, and chamber wall temperature. These parameters are provided to the user in the form of a recipe and can be entered using the user interface.

[0096] Signals for monitoring the process may be supplied by the analog and / or digital input connections of the system controller 629. Signals for controlling the process are output to the analog and digital output connections of the deposition unit 600.

[0097] The system software may be designed or configured in many different ways. For example, various chamber component subroutines or control objects may be created to control the operation of the chamber components necessary to carry out the deposition process according to the disclosed embodiment. Examples of programs or program parts for this purpose include substrate positioning code, processing gas control code, pressure control code, and heater control code.

[0098] In some implementations, the controller 629 is part of a system that may be part of the examples described above. Such a system may comprise a semiconductor processing apparatus such as a processing tool or group of tools, a chamber or group of chambers, a processing platform or group of platforms, and / or a specific group of processing components (such as a wafer pedestal or gas flow system). These systems may be integrated with electronic devices to control their operations before, during, and after processing of semiconductor wafers or substrates. These electronic devices may refer to “controllers” that can control various components or subparts of the system or group of systems. Depending on the processing requirements and / or the type of system, the controller 629 may be programmed to control any processes disclosed herein, including the supply of processing gases, temperature settings (e.g., heating and / or cooling), pressure settings, vacuum settings, power settings, settings for radio frequency (RF) generators in some systems, settings for RF matching circuits, frequency settings, flow rate settings, fluid supply settings, position and operation settings, and wafer transport between tools and other transport tools and / or load locks connected to or interfaced with a specific system.

[0099] A controller can be broadly defined as an electronic device having various integrated circuits, logic, memory, and / or software that receives and issues instructions, controls operations, performs cleaning operations, and performs endpoint measurements. Integrated circuits may include chips in the form of firmware storing program instructions, chips defined as digital signal processors (DSPs), application-specific integrated circuits (ASICs), and / or one or more microprocessors or microcontrollers that execute program instructions (e.g., software). Program instructions may be instructions transmitted to the controller in the form of various individual settings (or program files) that specify operating parameters for performing a particular process on a semiconductor wafer or a particular process for a semiconductor wafer or system. In some embodiments, operating parameters may be part of a recipe defined by a process engineer to implement one or more processing steps in the manufacturing of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or dies of a wafer.

[0100] In several implementations, the controller 629 may be part of a computer integrated into or coupled to the system, or otherwise networked to the system, or coupled to such a computer, or a combination thereof. For example, the controller 629 may be in the “cloud” or be all or part of a fab host computer system, which may enable remote access for 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 the parameters of the current process, set up a process step according to 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 have a user interface that enables input or programming of parameters and / or settings that will later be transmitted from the remote computer to the system. In some examples, the controller receives instructions in the form of data specifying the parameters of each process step to be performed in one or more operations. It should be understood that these parameters may be specific to the type of process being performed and the type of tool to which the controller is configured to interface or control. In such cases, the controllers may be distributed, for example, by having one or more separate controllers that are networked with each other and cooperate toward a common purpose, such as the processes and controls described herein, as described above. An example of such distributed controllers is one or more integrated circuits mounted in a chamber, which communicate with one or more remotely located integrated circuits (e.g., at the platform level or as part of a remote computer) to jointly control the processes in the chamber.

[0101] Exemplary 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, clean chambers or modules, bevel edge etching chambers or modules, physical vapor deposition (PVD) chambers or modules, CVD chambers or modules, 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 in the fabrication and / or manufacture of semiconductor wafers.

[0102] As described above, the controller may communicate with one or more of the following, depending on the processing steps or groups of steps performed by the tool: other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, neighboring tools, tools located throughout the factory, the main computer, other controllers, or tools used for material handling to move wafer containers between tool locations and / or load ports in a semiconductor manufacturing plant.

[0103] The controller 629 may include various programs. The substrate positioning program may include program code for controlling chamber components used to load the substrate onto the pedestal or chuck, and further, to control the distance between the substrate and other members of the chamber, such as a gas inlet, and / or a target. The processing gas control program may include code for controlling the gas composition, flow rate, and pulse time, and, optionally, for introducing gas into the chamber to stabilize the pressure inside the chamber before deposition. The pressure control program may include code for controlling the pressure inside the chamber, for example, by adjusting the throttle valve of the chamber's exhaust system. The heater control program may include code for controlling the current to a heating unit used to heat the substrate. Alternatively, the heater control program may control the supply of a heat transfer gas, such as helium, to the wafer chuck.

[0104] Examples of chamber sensors that may be monitored during deposition include mass flow controllers, pressure sensors such as manometers, and thermocouples placed on pedestals or chucks. Appropriately programmed feedback and control algorithms may be used, along with data from these sensors, to maintain desired process conditions.

[0105] The apparatus may include a gas manifold system that provides line filling to various gas distribution lines, as schematically shown in Figure 8. Manifold 804 has an input 802 from a source (not shown) of tungsten-containing precursor gas or molybdenum-containing precursor gas; manifold 811 has an input 809 from a source (not shown) of hydrogen or other reducing gas; and manifold 821 has an input 819 from a source (not shown) of inert purge gas. Manifolds 804, 811, and 821 supply the precursor gas, reducing gas, and purge gas to the deposition chamber via valved distribution lines 805, 813, and 825, respectively. To provide line filling, i.e., to pressurize the distribution lines, various valves are opened or closed. For example, to pressurize distribution line 805, valve 806 to vacuum is closed, and valve 808 is closed. After an appropriate time increment, valve 808 is opened to supply the precursor gas to the chamber. After an appropriate amount of time for gas supply, valve 808 is closed. The chamber can then be purged into a vacuum by opening valve 806 to a vacuum.

[0106] A similar process is used to supply the reducing gas and the purging gas. For example, to introduce the reducing gas, the distribution line 813 is filled by closing valve 815 and the valve to vacuum 817. By opening valve 815, the reducing gas can be supplied to the chamber. Similarly, to introduce the purging gas, the distribution line 825 is filled by closing valve 827 and the valve to vacuum 823. By opening valve 827, argon or other inert purging gas can be supplied to the chamber. The amount and timing of the initial gas supply will vary depending on the amount of time allowed for line filling.

[0107] Figure 6 further shows a vacuum pump that can open valves 806, 817, and 823, respectively, to purge the system. The supply of gas through the various distribution lines is controlled by a controller, such as a mass flow controller controlled by a microprocessor, digital signal processor, etc., which is programmed with flow rate, inflow duration, and process sequencing.

[0108] It should be noted that the above process may require precise timing of valves and mass flow controllers (MFCs) that supply reagent pulses to the semiconductor substrate during deposition. One way to achieve this is to issue valve and MFC commands to an embedded digital input / output controller (IOC) in discrete packets of information containing instructions for all time-critical commands for all or part of the PNL deposition sequence. Lam Research's ALTUS system provides at least one IOC sequence. These IOCs can be physically located in various places within the instrument, for example, within a processing module or on a standalone power rack some distance away from the processing module. Typically, there are multiple IOCs within each module (e.g., three per module). With respect to the actual instructions contained in a single sequence, all commands for controlling the valves (for all carrier and reaction gases) and setting the MFC flow rates may be included in a single IOC sequence. This ensures that the timing of all devices is strictly controlled, both in an absolute sense and in relation to one another. Typically, multiple IOC sequences are running at any given time. This allows for the execution of PNL, for example, at stations 1 and 2, with all timing control for all hardware components necessary to deposit the PNL-W nucleation layer at these stations. A second sequence may be executed simultaneously at other deposition stations within the same module to deposit bulk tungsten using the above timing sequence. While the relative timing of the devices controlling the supply of reagents to stations 3 and 4 is important within that group of devices, the relative timing of the PNL process at stations 1 and 2 can be offset from the relative timing of stations 3 and 4. The IOC converts the information in the packetized sequence and issues digital or analog command signals directly to the MFC or pneumatic solenoid bank controlling the valves.

[0109] The tungsten-containing gas pulse may be generated as follows: First, the system generates WCl over a period of time while the MFC or other flow control device is stable. x The gas is then diverted to a vacuum pump. This may be done over a period of approximately 0.5 to 5 seconds, in one example. Next, the system pressurizes the tungsten gas supply manifold by closing both the diversion outlet 606 and the outlet 608 to the deposition chamber. This may be done over a period of approximately 0.1 to 5 seconds, for example, to generate the first burst of the reagent when the outlet to the deposition chamber is opened. This is achieved, in one example, by opening the outlet valve 808 over a period of approximately 0.1 to 10 seconds. Subsequently, the tungsten-containing gas is purged from the deposition chamber using an appropriate purge gas. Pulsed flows of other reagents may be generated in a similar manner. Pulses of molybdenum-containing gas may be generated in a similar manner.

[0110] The above describes the implementation of embodiments of the disclosure in single or multi-chamber semiconductor processing tools. The apparatus and processes described herein may be used in combination with lithography patterning tools and processes for, for example, the fabrication or manufacture of semiconductor devices, displays, LEDs, solar panels, etc. Generally, such tools / processes are used or performed together in common manufacturing equipment, though not necessarily. Lithography patterning of films typically includes some or all of the following steps, each of which is performed using several possible tools. (1) Apply photoresist to a workpiece i.e., a substrate using a spin-type or spray-type tool; (2) Cure the photoresist using a hot plate, furnace, or UV curing tool; (3) Expose the photoresist to visible light, ultraviolet light, or X-rays using a tool such as a wafer stepper; (4) Develop the resist to selectively remove it using a tool such as a wet bench, thereby forming a pattern; (5) Transfer the resist pattern to the underlying film or workpiece using a dry or plasma-assisted etching tool; (6) Remove the resist using a tool such as an RF or microwave plasma resist stripper.

[0111] [Conclusion] While the embodiments described above are presented in some detail for the purpose of clear understanding, it will be apparent that some modifications and alterations may be made within the scope of the appended claims. It should be noted that there are numerous alternative forms of implementing the processes, systems, and apparatus of the embodiments of the present invention. Therefore, the embodiments of the present invention should be considered illustrative and not limiting, and the embodiments are not limited to the details presented herein. The present invention can also be realized in the following embodiments, for example. Application Example 1: It is a method, Prepare the structure to be filled with the metal-containing material, This includes exposing the aforementioned structure to multiple deposition cycles, where each deposition cycle is Hydrogen (H 2 ) Exposure to pulses and subsequent exposure to inert gas purge pulses, A method comprising exposure to multiple alternating metal precursor pulses and inert gas purge pulses. Application example 2: A method according to Application Example 1, wherein the metal is tungsten (W) or molybdenum (Mo). Application Example 3: A method according to Application Example 1, wherein the metal precursor is a chlorine-containing metal precursor. Application Example 4: A method according to Application Example 3, wherein the chlorine-containing metal precursor comprises tungsten chloride or tungsten oxychloride. Application Example 5: The method of Application Example 4, wherein the chlorine-containing metal precursor is WCl 5 and WCl 6 A method that includes at least one of the following. Application example 6: A method according to Application Example 3, wherein the chlorine-containing metal precursor comprises molybdenum chloride or molybdenum oxychloride. Application example 7: The method of application example 6, wherein the chlorine-containing metal precursor is MoCl 5 MoO 2 Cl 2 , and MoOCl 4 A method that includes at least one of the following. Application Example 8: A method according to Application Example 3, wherein the pulse of the chlorine-containing metal precursor contains a chlorine-containing tungsten precursor in an amount between approximately 0.1% and approximately 1.5% by volume. Application example 9: A method of Application Example 1, wherein the exposure to multiple alternating metal precursor pulses and inert gas purge pulses includes turning off the flow of the inert gas purge during the metal precursor pulses. Application Example 10: A method according to Application Example 1, wherein the duration of the inert gas purge pulse is at least 1.5 times the duration of the metal precursor pulse. Application Example 11: A method according to Application Example 1, wherein each deposition cycle comprises at least five alternating metal precursor pulses and inert gas purge pulses. Application Example 12: A method according to Application Example 1, wherein each deposition cycle comprises at least 10 alternating metal precursor pulses and inert gas purge pulses. Application Example 13: The method of Application Example 1, in which each sedimentation cycle is performed only once. 2 A method that includes pulses. Application Example 14: The method of Application Example 1, in which each sedimentation cycle is performed by multiple alternating H 2 A method comprising pulses and inert gas pulses. Application Example 15: A method of application example 1, wherein the structure is a three-dimensional (3D) NAND structure in the process of being manufactured, the 3D NAND structure having a side wall and a plurality of openings in the side wall, the openings being connected to a plurality of features having a plurality of fluid-accessible internal regions through the openings. Application Example 16: It is a device, One or more processing chambers, each configured to hold a substrate, Hydrogen (H 2 ) One or more processing gas inlets for coupling with a gas source, a metal precursor gas source, and an inert purge gas source, The apparatus comprises a controller for controlling the operation of the apparatus, the controller including machine-readable instructions for executing multiple deposition cycles, each deposition cycle being: Hydrogen (H) is supplied to the one or more processing chambers via the one or more processing gas inlets. 2 ) Injecting pulses, The aforementioned H 2 After pulse injection, an inert purge gas pulse is injected into one or more processing chambers via one or more processing gas inlets, Apparatus comprising injecting multiple alternating metal precursor pulses and inert gas purge pulses into one or more processing chambers via one or more processing gas inlets after injecting the inert purge gas pulse. Application Example 17: Apparatus according to Application Example 16, wherein the metal precursor is a chlorine-containing precursor. Application Example 18: Apparatus of Application Example 17, wherein the metal precursor comprises at least one of tungsten chloride, tungsten oxychloride, molybdenum chloride, and molybdenum oxychloride. Application Example 19: Apparatus of Application Example 16, wherein the command includes a command to turn off the flow of the inert gas purge during the metal precursor pulse. Application Example 20: Apparatus of Application Example 16, wherein the duration of the inert gas purge pulse is at least 1.5 times the duration of the metal precursor pulse. Application Example 21: Apparatus of Application Example 16, wherein each deposition cycle includes at least five alternating metal precursor pulses and inert gas purge pulses. Application Example 22: It is a method, Prepare the structure to be filled with the metal-containing material, This includes exposing the aforementioned structure to multiple deposition cycles, where each deposition cycle is Multiple alternating hydrogen (H 2 ) Exposure to pulses and inert gas purge pulses, A method comprising exposure to a metal precursor pulse and a subsequent inert gas purge pulse. Application Example 23: A method according to Application Example 22, wherein the metal is tungsten (W) or molybdenum (Mo). Application Example 24: A method according to Application Example 22, wherein the metal precursor is a chlorine-containing precursor. Application Example 25: A method according to Application Example 24, wherein the chlorine-containing metal precursor comprises tungsten chloride or tungsten oxychloride. Application Example 26: A method according to Application Example 24, wherein the chlorine-containing metal precursor comprises molybdenum chloride or molybdenum oxychloride. Application Example 27: The method of application example 24, wherein the chlorine-containing metal precursor is WCl 5 WCl 6 MoCl 5 MoO 2 Cl 2 , and MoOCl 4 A method that includes at least one of the following. Application Example 28: A method according to Application Example 24, wherein the pulse of the chlorine-containing metal precursor contains a chlorine-containing tungsten precursor in an amount between approximately 0.1% and approximately 1.5% by volume. Application Example 29: The method of application example 22, wherein multiple alternating H 2 The exposure to the pulse and the inert gas purge pulse is the H 2 A method comprising turning off the flow of the inert gas purge during a pulse. Application Example 30: The method of application example 22, wherein the duration of the inert gas purge pulse is the H 2 A method in which the duration of the pulse is at least 1.5 times the duration of the pulse. Application Example 31: The method of application example 22, wherein each deposition cycle consists of at least 5 alternating H 2 A method comprising a pulse and an inert gas purge pulse. Application Example 32: A method of application example 22, wherein each deposition cycle comprises at least 10 alternating metal precursor pulses and inert gas purge pulses. Application Example 33: A method of application example 22, wherein each deposition cycle includes only one metal precursor pulse. Application Example 34: A method of application example 22, wherein each deposition cycle comprises multiple alternating metal precursor pulses and inert gas purge pulses. Application Example 35: A method of application example 22, wherein the structure is a three-dimensional (3D) NAND structure in the process of being manufactured, the 3D NAND structure having a side wall and a plurality of openings in the side wall, the openings being connected to a plurality of features having a plurality of fluid-accessible internal regions through the openings. Application Example 36: It is a device, One or more processing chambers, each configured to hold a substrate, Hydrogen (H 2 ) One or more processing gas inlets for coupling with a gas source, a metal precursor gas source, and an inert purge gas source, The apparatus comprises a controller for controlling the operation of the apparatus, the controller including machine-readable instructions for executing multiple deposition cycles, each deposition cycle being: Multiple alternating hydrogen (H) gases are supplied to the one or more processing chambers via the one or more processing gas inlets. 2 ) Injecting pulses and inert gas purge pulses, Injecting metal precursor pulses into one or more processing chambers through one or more processing gas inlets, An apparatus comprising injecting purge gas pulses into one or more processing chambers through one or more processing gas inlets. Application Example 37: Apparatus according to Application Example 36, wherein the metal precursor is a chlorine-containing precursor. Application Example 38: Apparatus of Application Example 37, wherein the metal precursor comprises at least one of tungsten chloride, tungsten oxychloride, molybdenum chloride, and molybdenum oxychloride.

Claims

1. It is a method, The preparation of a structure to be filled with a metal-containing material, wherein the structure is a partially constructed three-dimensional (3D) NAND structure, the 3D NAND structure having side walls and a plurality of openings in the side walls, the openings leading to a plurality of features having a plurality of fluid-accessible internal regions through the openings, and the preparation of the structure. This includes exposing the structure to multiple deposition cycles to deposit the metal-containing material over the entire structure, including the deepest region of the structure, with each deposition cycle being: Multiple alternating hydrogen (H 2 ) Exposure to pulses and inert gas purge pulses, each H 2 During the pulse, hydrogen is adsorbed onto the surface of the structure, and unadsorbed hydrogen is released during each inert gas purge pulse. 2 They will be purged, exposed, H 2 A method comprising exposure to multiple alternating metal precursor pulses and inert gas purge pulses without intervening pulses, wherein the metal precursor is a chlorine-containing metal precursor supplied from a pressurized tank and reacts with the adsorbed hydrogen.

2. A method according to claim 1, wherein the metal is tungsten (W) or molybdenum (Mo).

3. A method according to claim 1, wherein the chlorine-containing metal precursor comprises tungsten chloride or tungsten oxychloride.

4. A method according to claim 1, wherein the chlorine-containing metal precursor comprises molybdenum chloride or molybdenum oxychloride.

5. The method according to claim 1, wherein the chlorine-containing metal precursor is WCl 5 , WCl 6 , MoCl 5 , MoO 2 Cl 2 , and at least one of MoOCl 4 .

6. A method according to claim 1, wherein the pulse of the chlorine-containing metal precursor comprises a chlorine-containing tungsten precursor in an amount between about 0.1% and about 1.5% by volume.

7. The method according to claim 1, wherein multiple alternating H 2 The exposure to the pulse and the inert gas purge pulse is the H 2 A method comprising turning off the flow of the inert gas purge during a pulse.

8. The method according to claim 1, wherein the duration of the inert gas purge pulse is the H 2 A method in which the duration of the pulse is at least 1.5 times the duration of the pulse.

9. The method according to claim 1, wherein each deposition cycle comprises at least five alternating H 2 A method comprising a pulse and an inert gas purge pulse.

10. A method according to claim 1, wherein each deposition cycle comprises at least 10 alternating metal precursor pulses and inert gas purge pulses.

11. A method according to claim 1, wherein each deposition cycle comprises only one metal precursor pulse.

12. A method according to claim 1, wherein each deposition cycle comprises a plurality of alternating metal precursor pulses and inert gas purge pulses.

13. It is a device, One or more processing chambers, each configured to hold a substrate, Hydrogen (H 2 ) One or more processing gas inlets for coupling with a gas source, a metal precursor gas source, and an inert purge gas source, The apparatus comprises a controller for controlling the operation of the apparatus, the controller comprising machine-readable instructions for executing multiple deposition cycles to deposit a metal-containing material over the entire structure, including the deepest region of the structure, the structure being a partially constructed three-dimensional (3D) NAND structure, the 3D NAND structure having side walls, and a plurality of openings in the side walls, the openings leading to a plurality of features having a plurality of fluid-accessible internal regions through the openings, and each deposition cycle comprises machine-readable instructions, Multiple alternating hydrogen (H) gases are supplied to the one or more processing chambers via the one or more processing gas inlets. 2 ) Injecting pulses and inert gas purge pulses into the surface of the structure provided on the substrate, each H 2 Hydrogen is adsorbed during the pulse, and unadsorbed hydrogen is present during each inert gas purge pulse. 2 It is purged, injected, H 2 Without inserting a pulse, The process involves alternately injecting a metal precursor pulse and an inert gas purge pulse multiple times into one or more processing chambers via one or more processing gas inlets, wherein the metal precursor is a chlorine-containing metal precursor supplied from the metal precursor gas source, and reacts with the adsorbed hydrogen, and the injection of the metal precursor pulses An apparatus comprising injecting a plurality of purge gas pulses into one or more processing chambers through one or more processing gas inlets.

14. The apparatus according to claim 13, wherein the metal precursor comprises at least one of tungsten chloride, tungsten oxychloride, molybdenum chloride, and molybdenum oxychloride.

15. It is a method, This involves preparing a structure to be filled with a metal-containing material. The aforementioned structure is a partially constructed three-dimensional (3-D) NAND structure, Side walls and, Preparation of the structure, which has a plurality of openings in the side wall, each opening leading to a plurality of features having a plurality of internal regions that are fluidly accessible through the openings, This includes exposing the structure to multiple deposition cycles to deposit the metal-containing material over the entire structure, including the deepest region of the structure, with each deposition cycle being: Hydrogen (H 2 ) Exposure to pulses and subsequent exposure to inert gas purge pulses, H 2 A method comprising exposure of a structure to multiple alternating metal precursor pulses and inert gas purge pulses without intervening pulses, wherein the metal precursor is a chlorine-containing metal precursor supplied from a pressurized tank, and the duration of one inert gas purge pulse is 1.5 times that of the preceding metal precursor pulse.

16. A method according to claim 15, wherein the metal is tungsten (W) or molybdenum (Mo).

17. A method according to claim 15, wherein the chlorine-containing metal precursor comprises tungsten chloride or tungsten oxychloride.

18. The method according to claim 17, wherein the chlorine-containing metal precursor is WCl 5 and WCl 6 A method that includes at least one of the following.

19. A method according to claim 15, wherein the chlorine-containing metal precursor comprises molybdenum chloride or molybdenum oxychloride.

20. The method according to claim 19, wherein the chlorine-containing metal precursor is MoCl 5 MoO 2 Cl 2 , and MoOCl 4 A method that includes at least one of the following.

21. A method according to claim 15, wherein the pulse of the chlorine-containing metal precursor comprises a chlorine-containing tungsten precursor in an amount between about 0.1% and about 1.5% by volume.

22. A method according to claim 15, wherein the exposure to a plurality of alternating metal precursor pulses and inert gas purge pulses includes turning off the flow of the inert gas purge during the metal precursor pulses.

23. A method according to claim 15, wherein the duration of the inert gas purge pulse is at least three times the duration of the metal precursor pulse.

24. A method according to claim 15, wherein each deposition cycle comprises at least five alternating metal precursor pulses and an inert gas purge pulse.

25. A method according to claim 15, wherein each deposition cycle comprises at least 10 alternating metal precursor pulses and inert gas purge pulses.

26. The method according to claim 15, wherein each deposition cycle is one H 2 A method that includes pulses.

27. The method according to claim 15, wherein each deposition cycle comprises multiple alternating H 2 A method comprising pulses and inert gas pulses.

28. It is a device, One or more processing chambers, each configured to hold a substrate, wherein the substrate has a structure, The aforementioned structure is a partially constructed three-dimensional (3-D) NAND structure, Side walls and, A processing chamber having a plurality of openings in the side wall, each opening connected to a plurality of features having a plurality of internal regions that are fluidly accessible through the openings, Hydrogen (H 2 ) One or more processing gas inlets for coupling with a gas source, a metal precursor gas source, and an inert purge gas source, The apparatus comprises a controller for controlling the operation of the apparatus, the controller including machine-readable commands for executing multiple deposition cycles to deposit metal-containing material over the entire structure, including the deepest region of the structure, each deposition cycle being, Hydrogen (H) is supplied to the one or more processing chambers via the one or more processing gas inlets. 2 ) Injecting pulses, H 2 Without inserting a pulse in between, The aforementioned H 2 After pulse injection, an inert purge gas pulse is injected into one or more processing chambers via one or more processing gas inlets, An apparatus comprising injecting multiple alternating metal precursor pulses and inert gas purge pulses into one or more processing chambers via one or more processing gas inlets after injecting the inert purge gas pulse, wherein the metal precursor is a chlorine-containing metal precursor supplied from a pressurized tank, and the duration of one inert gas purge pulse is 1.5 times that of the preceding metal precursor pulse.

29. The apparatus according to claim 28, wherein the metal precursor comprises at least one of tungsten chloride, tungsten oxychloride, molybdenum chloride, and molybdenum oxychloride.

30. The apparatus according to claim 28, wherein the command includes a command to turn off the flow of the inert gas purge during the metal precursor pulse.

31. The apparatus according to claim 28, wherein the duration of the inert gas purge pulse is at least three times the duration of the metal precursor pulse.

32. The apparatus according to claim 28, wherein each deposition cycle comprises at least five alternating metal precursor pulses and an inert gas purge pulse.

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