Method for filling gaps in substrates

Abstract

The present disclosure provides a method for processing a film layer on a substrate, including positioning the substrate in a processing region of a processing chamber. The substrate can have high aspect ratio features extending in a depth direction from the substrate surface to a bottom surface. The features can have a width defined by a first sidewall and a second sidewall. A film having a composition including a metal is formed on the substrate surface and on the first sidewall, second sidewall, and bottom surface of each feature. The film of the feature can have a seam extending substantially parallel to the first and second sidewalls. The film is annealed and exposed to oxygen radicals, converting the metal of the film to a metal oxide. The metal oxide is exposed to hydrogen radicals, converting the metal oxide to a metal fill layer.

Description

[Technical field]

[0001] TECHNICAL FIELD

[0001] Embodiments of the present disclosure relate generally to systems and methods for manufacturing semiconductor devices. More specifically, the present disclosure is directed to systems and methods for processing substrates. [Background technology]

[0002]

[0002] In the manufacture of microelectronic devices, it is necessary to fill narrow trenches without voids for many applications. One application is for shallow trench isolation (STI). In this application, films need to be of high quality and with very low leakage throughout the trench. Chemical vapor deposition (CVD) and atomic layer deposition (ALD) are techniques used to deposit films into the trenches. The as-deposited films undergo processing steps such as water vapor annealing and UV curing to improve the film quality.

[0003]

[0003] As feature dimensions decrease and aspect ratios increase, post-cure methods for as-deposited flowable films become challenging, resulting in films with compositional variations across the filled trench. In three-dimensional structures, seams are often observed in the filled trench after film deposition. For example, conventional plasma-based film deposition processes often result in "mushroom" films forming in narrow trenches because the plasma cannot penetrate deep into the trench. This results in pinching off of the narrow trench from the top, creating voids or seams in the trench. These seams can open or become exposed after processing, causing structural defects.

[0004] Therefore, there is a need for a method of gap filling in high aspect ratio structures that can provide seam-free film growth. Summary of the Invention

[0005] In some embodiments, a method for processing a film layer on a substrate is provided that includes positioning the substrate in a processing region of a processing chamber. The substrate has at least one feature extending in a depth direction from a substrate surface to a bottom surface. The feature has a width defined by a first sidewall and a second sidewall. A film having a composition including a metal is formed on the substrate surface and on the first sidewall, the second sidewall, and the bottom surface of each feature. The film of the feature has a seam extending substantially parallel to the first and second sidewalls. The film is heated at a temperature of about 300° C. to about 1000° C. The film in the seam is exposed to oxygen radicals while converting the metal of the film to a metal oxide. The seam may be at least partially filled with the metal oxide or may be completely filled with the metal oxide. The method includes exposing the metal oxide to hydrogen radicals while converting the metal oxide to a metal filled layer.

[0006] In some embodiments, a method for processing a film layer on a substrate is provided that includes positioning the substrate in a processing region of a processing chamber. The substrate includes at least one feature extending in a depth direction from a substrate surface to a bottom surface. The feature has a width defined by a first sidewall and a second sidewall, and a film comprised of a metal material or a metal nitride material disposed along the first sidewall, the second sidewall, and the bottom surface of the at least one feature. The film has a seam extending between at least a portion of the film formed on the first sidewall and at least a portion of the film formed on the second sidewall. The film in the seam is exposed to oxygen radicals while converting the metal material to a metal oxide or the metal nitride material to a metal oxynitride material. The seam is at least partially filled with the metal oxide or metal oxynitride material. The metal oxide or metal oxynitride material can be exposed to hydrogen radicals while converting the metal oxide to a metal fill layer or converting the metal oxynitride material to a metal nitride fill layer.

[0007] In some embodiments, a method for processing a film layer on a substrate is provided that includes positioning the substrate in a first processing region of a first processing chamber. The substrate includes at least one feature extending in a depth direction from the substrate surface to a bottom surface. The feature has a width defined by a first sidewall and a second sidewall. A film having a composition including a metal is formed on the substrate surface and on the first sidewall, the second sidewall, and the bottom surface of each feature. The film of the feature has a seam extending substantially parallel to the first and second sidewalls. The substrate is positioned in a second processing chamber having a second processing region and heated at a temperature of about 400° C. to about 650° C. The film in the seam is exposed to oxygen radicals while converting the metal of the film to a metal oxide. The seam may be at least partially filled with the metal oxide or may be completely filled with the metal oxide. The method includes exposing the metal oxide to hydrogen radicals while converting the metal oxide to a metal filled layer. To convert the metal fill layer to a metal nitride fill layer, the metal fill layer is exposed to nitrogen radicals.

[0008] So that the above-recited features of the present disclosure can be understood in detail, a more particular description of the disclosure summarized above will be rendered by reference to embodiments, some of which are illustrated in the accompanying drawings. [Brief description of the drawings]

[0009] [Figure 1A] 1 is a cross-sectional schematic diagram illustrating substrate features prior to deposition of a membrane layer according to an embodiment of the present disclosure. [Figure 1B] 2A-2C are cross-sectional schematic diagrams illustrating substrate features after deposition of a membrane layer according to an embodiment of the present disclosure. [Diagram 2] FIG. 1 is a flow diagram illustrating an exemplary method for processing a substrate according to an embodiment of the present disclosure. [Figure 3A] 2A-2C are cross-sectional schematic diagrams illustrating substrate features after deposition of a film layer and exposure to a first radical species, according to an embodiment of the present disclosure. [Figure 3B] 4A-4C are cross-sectional schematic diagrams illustrating substrate features after deposition of a film layer and exposure to a second radical species according to an embodiment of the present disclosure. [Figure 3C]2A-2C are cross-sectional schematic diagrams illustrating substrate features after deposition of a membrane layer and after performing a method of the present disclosure, according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010]

[0015] To facilitate understanding, wherever possible, the same reference numerals have been used to designate identical elements common to the figures. It is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation.

[0011]

[0016] It should be noted, however, that the attached drawings merely depict exemplary embodiments of the present disclosure and therefore should not be considered as limiting the scope of the present disclosure, which may also permit other equally effective embodiments.

[0012]

[0017] Before embodiments of the present disclosure are described, it is to be understood that the disclosure is not limited to the details of construction or methods set forth in the following description as the disclosure is capable of other embodiments and of being practiced or carried out in various ways.

[0013]

[0018] As used herein, "substrate" refers to any substrate or material surface formed on a substrate on which a film treatment is performed during a manufacturing process. For example, substrate surfaces on which treatment is performed include materials such as silicon, silicon oxide, strained silicon, silicon-on-insulator (SOI), carbon-doped silicon oxide, amorphous silicon, doped silicon, germanium, gallium arsenide, glass, sapphire, and any other materials such as metals, metal nitrides, metal alloys, and other conductive materials, depending on the application. Substrates include, but are not limited to, semiconductor wafers. Substrates are exposed to pretreatment processes that polish, etch, reduce, oxidize, hydroxylate, anneal, UV cure, e-beam cure, and / or bake the substrate surface. In addition to performing film treatments directly on the surface of the substrate itself, the present disclosure may perform any of the disclosed film treatment steps on an underlying layer formed on the substrate as disclosed in more detail below, and the term "substrate surface" is intended to include such underlying layers as the context indicates. Thus, for example, when a film / layer or partial film / layer is deposited on a substrate surface, the exposed surface of the newly deposited film / layer becomes the substrate surface.

[0014]

[0019] Certain aspects of the present disclosure provide systems and methods for processing substrates having high aspect ratio features. Some embodiments provide methods for obtaining seamless metal, metal nitride, or metal alloy films for filling high aspect ratio trenches. For example, the high aspect ratio features processed include trenches in 3D structures such as memory and logic devices, such as metal gate layers of Fin Field Effect Transistors ("FinFETs"), Gate-All-Around Field Effect Transistors ("GAA FETs"), Dynamic Random Access Memory ("DRAM"), and logic devices such as vertical NAND ("V-NAND") structures.

[0015]

[0020] 1A and 1B are cross-sectional schematic diagrams showing a substrate 100 having a feature 108. The figures show a substrate with a single feature for illustrative purposes, but one of ordinary skill in the art will understand that there may be multiple features. The shape of the feature 108 may be any suitable shape, including, but not limited to, a trench and a cylindrical via. As used herein, the term "feature" means any intentional surface irregularity. Suitable examples of features include, but are not limited to, a trench having a top, two sidewalls and a bottom, and a fin having a top and two walls. The feature may have any suitable aspect ratio (ratio of the depth of the feature to the width of the feature). In some embodiments, the aspect ratio is at least about 5:1, such as from about 5:1 to about 50:1, alternatively at least about 10:1, such as at least about 20:1.

[0016]

[0021] 2 is a flow diagram illustrating an exemplary method for processing a metal film layer according to an embodiment of the present disclosure. Referring to FIG. 2 and FIG. 1A and FIG. 1B, a substrate 100 is positioned for processing in a first processing region of a first processing chamber in step 202. The substrate 100 has at least one feature 108 extending in a depth direction from a substrate surface 102 to a bottom surface 110, the at least one feature 108 having a width defined by a distance between a first sidewall 104 and a second sidewall 106, as shown in FIG. 1A.

[0017]

[0022] In step 204, a film 112 is formed on the substrate 100, as shown in FIG. 1B. The film may be any suitable film composed of at least one metal. The metal may be selected from tantalum (Ta), titanium (Ti), tungsten (W), chromium (Cr), cobalt (Co), aluminum (Al), copper (Cu), molybdenum (Mo), rubidium (Rb), tantalum nitride (TaN), titanium nitride (TiN), tungsten nitride (WN), chromium nitride (CrN), aluminum nitride (AlN), rubidium nitride (RbN), alloys thereof, or combinations thereof. In some embodiments, which may be combined with other embodiments, the film may be a metal nitride, such as TaN, TiN, WN, CrN, AlN, RbN, alloys thereof, or combinations thereof. In some embodiments, which may be combined with other embodiments, the film may be a metal Ta, Ti, W, Cr, Co, Al, Cu, Mo, Rb, alloys thereof, or combinations thereof.

[0018]

[0023] In some embodiments, which may be combined with other embodiments, the film or coating is formed by chemical vapor deposition (CVD), although other suitable methods are contemplated, such as plasma enhanced chemical vapor deposition (PE-CVD), atomic layer deposition (ALD), and plasma enhanced atomic layer deposition (PE-ALD). The film is formed conformally to at least one feature. As used herein, the terms "conformal" or "conformally" refer to a layer that adheres to and uniformly covers an exposed surface with a thickness that has a variation of less than 1% relative to the average thickness of the film. In at least one example, a 1000 Å thick film has a thickness variation of less than 10 Å, such as about 1 Å to 10 Å. The thickness and variation includes the edges, corners, sides, and bottom of the recess. In some embodiments, which may be combined with other embodiments, the conformal layer is deposited by ALD, which provides coverage over the deposition area of ​​essentially uniform thickness on the complex surface.

[0019]

[0024] In some embodiments, which can be combined with other embodiments, the film 112 is a continuous film. As used herein, the term "continuous" refers to a layer that covers the entire exposed surface with no gaps or non-plating that reveal the material underlying the deposited layer. A continuous layer has gaps or non-plating that have a surface area of ​​less than about 1% of the total surface area of ​​the film.

[0020]

[0025] The film 112 is formed on the substrate surface 102, the first sidewall 104 of the feature 108, the second sidewall 106 of the feature 108, and the bottom surface 110 of the feature 108. In some embodiments, which can be combined with other embodiments, the film 112 of the substrate 100 is heated before or while the film is deposited on the substrate. The film is heated to a temperature of at least 300° C., e.g., from 300° C. to about 1000° C., e.g., from about 400° C. to about 650° C., e.g., from about 400° C. to about 500° C., e.g., about 450° C. The deposition temperature is selected based on the film composition, the deposition method, the pressure of the processing chamber, the temperature required to anneal the film, or a combination thereof. By forming the film 112, a seam 120 is formed. The seam 120 extends substantially parallel to the first and second sidewalls 104, 106. The seam 120 has a seam width 114 defined by the distance between a first seam wall 116 and a second seam wall 118. The seam width varies along the length of the seam. The seam width 114 refers to the portion of the seam that has the greatest width along the length of the seam 120. In some embodiments, the seam width is from about 2 Å to about 50 Å, e.g., from about 2 Å to about 20 Å, e.g., from about 3 Å to about 10 Å, as measured by TEM.

[0021]

[0026] In step 206, the film surface, including the film inside the seam, is exposed to oxygen radicals while converting at least a portion of the metal or metal nitride on the film surface to a metal oxide. The portion of the film surface that is converted is about 2 Å to about 150 Å, e.g., about 2 Å to about 100 Å, e.g., about 5 Å to about 50 Å thick inward from each of the seam sidewalls 104, 106. The seam is at least partially filled with metal oxide or metal oxynitride. Without being bound by theory, it is believed that under annealing conditions, metal or metal nitride ions in the film react with oxygen atoms on the surface to form larger metal oxide or metal oxynitride molecules on the film surface. The larger molecules create stress and oxide displacement at the grain boundaries, which can bond adjacent grains as they recrystallize, thus causing grain growth. The enlarged grains can conformally expand the film at the film surface, including the film in the seam. Thus, the seam is at least partially filled with the expanded film. A substrate 302 having a seam that is at least partially filled with a metal oxide or metal oxynitride 322 is shown in FIG. 3A. In some embodiments, which may be combined with other embodiments, the seam is substantially filled with a metal oxide. The metal oxide is selected from AlO, TiO, TaO, WO, CrO, CoO, CuO, MoO, RbO, alloys thereof, or combinations thereof. In some embodiments, which may be combined with other embodiments, the seam is substantially filled with a metal oxynitride. The metal oxynitride is selected from AlON, TiON, TaON, WON, CrON, CoON, CuON, MoON, RbON, alloys thereof, or combinations thereof. The conditions described herein allow the film to be partially oxidized and expanded to partially fill the seam without over-oxidizing the entire film. Over-oxidizing the film may result in device failure or resistivity outside of the range targeted for a given application. Furthermore, the inventors have discovered that over-oxidizing the film makes it difficult for hydrogen to reduce the film if it is overly expanded with large metal oxide or metal oxynitride molecules. In particular, the seam must be large enough to accommodate hydrogen atoms. The width of the seam after oxidation is greater than 1.2 Å, e.g., from about 1.5 Å to about 5 Å, e.g., from 2 Å to about 5 Å.

[0022]

[0027] In some embodiments, which may be combined with other embodiments, step 206 is performed in a first processing chamber. In some embodiments, which may be combined with other embodiments, step 206 is performed in a second processing chamber having a second processing region. The substrate 100 shown in FIG. 1B having the film 112 thereon is positioned in a second processing chamber having a second processing region and exposed to oxygen radicals. In some embodiments, the film 112 of the substrate 100 is heated to a temperature of at least 300° C., for example, from 300° C. to about 1000° C., for example, from about 400° C. to about 650° C., for example, from about 400° C. to about 500° C., for example, about 450° C. In some embodiments, the second processing region is maintained below atmospheric pressure. The pressure in step 206 is maintained at about 0.2 torr to about 5 torr, for example, from about 0.3 torr to about 5 torr, for example, from about 0.5 torr to about 5 torr, for example, from about 2 torr to about 4 torr, for example, about 3 torr. In at least one embodiment, the pressure of the second processing region is about 0.2 torr to about 5 torr, such as about 0.3 torr to about 5 torr, such as about 0.5 torr to about 5 torr, such as about 2 torr to about 4 torr, such as about 3 torr. In some embodiments, which can be combined with other embodiments, the oxygen radicals are formed in a plasma source. The plasma source is selected from a remote plasma source, an inductively coupled plasma source, and a microwave plasma source. In some embodiments, the plasma source includes an excitation source, such as radio frequency (RF). In step 206, the RF power for plasma generation is about 2 kW to about 10 kW, such as about 7 kW to about 9 kW, such as about 8 kW. The oxygen radicals are formed outside the processing region and flowed into the processing region, or the oxygen radicals are formed inside the processing region.

[0023]

[0028] For radicals formed inside the processing region, operating at too low a pressure has been found to increase ion sputtering which causes deformation of the surface or faceting of the edges and / or corners of the film. For radicals formed remote from the processing region, ion sputtering is not a concern because these processes include ion filters that screen the ions before they enter the processing region. However, for radicals formed inside or outside the processing region, low pressure has been found to limit the radical density and thus the reactants available to heal the film seams. Operating at too high a pressure impacts the ability of the plasma to sustain itself in the chamber. Thus, operating pressures of about 0.3 torr to about 5 torr are used in the chamber.

[0024]

[0029] The oxygen radicals are formed from an oxygen-containing gas, for example oxygen (O2 gas). The film is exposed to the oxygen radicals for about 100 seconds to about 600 seconds, for example about 200 seconds to about 400 seconds, for example about 300 seconds. In some embodiments, which can be combined with other embodiments, the oxygen radicals are introduced into the processing chamber with a first gas. The first gas is selected from H2, Ar, Kr, Xe, N2, He, Ne, and combinations thereof. In some embodiments, the oxygen radicals are introduced into the processing region at a flow rate of about 0.1 standard liters per minute (slm) to about 10 slm, for example about 1 slm to about 6 slm, for example about 2 slm to about 4 slm, for example about 3 slm, or about 4 slm, or about 5 slm. The oxygen radicals are introduced into the processing region with a first gas, which may include argon gas and hydrogen gas. In some embodiments, which may be combined with other embodiments, an oxygen-containing gas may be introduced into the processing region, and the oxygen-containing molecules may be dissociated into oxygen radicals by energizing them with an RF source. In some embodiments, a component of the first gas, such as argon and / or hydrogen, may facilitate dissociation of the oxygen molecules into oxygen radicals. In at least one example, the oxygen radicals flowing into the processing chamber are about 40% to about 100% by volume of the total gas flowing into the processing region. In some embodiments, in step 206, the argon gas may flow into the processing region at a rate of about 0.1 slm to about 10 slm, such as about 1 slm to about 6 slm, for example about 2 slm to about 4 slm, for example about 3 slm, or about 4 slm, or about 5 slm. In at least one example, the argon gas flowing into the processing chamber in step 206 is about 0% to about 50% by volume of the total gas flowing into the processing region in step 206. In some embodiments, which can be combined with other embodiments, hydrogen gas can be flowed into the processing region at a rate of about 0.1 slm to about 1 slm, about 0.2 slm to about 0.5 slm, such as about 0.3 slm, or about 0.4 slm, or about 0.5 slm, from about 0.1 slm to about 5 slm, such as about 0.3 slm, or about 0.4 slm, or about 0.5 slm, in step 206. In at least one example, the hydrogen gas flowing into the processing chamber is about 0% to about 50% by volume of the total gas flowing into the processing region in step 206.

[0025]

[0030] Without being bound by theory, it is believed that exposing the film to oxygen radicals in the presence of heat allows the film to grain / grow, allowing the seam width to "heal" and decrease. For example, a titanium nitride (TiN) film is exposed to oxygen radicals to introduce oxygen dopants into the film. Because TiO is larger than TiN, an expansion in the volume of the film may be observed, which may also result in a decrease in the seam width. It has been found that increasing the temperature of the film in the absence of oxygen does not reduce the size of the seams in the film. By exposing the film to oxygen radicals under the conditions described herein, it is observed that the film oxidizes to a composition that includes a combination of molecules formed from titanium, oxygen, and nitrogen atoms. Because titanium oxide can adversely affect resistivity in some applications, the inventors have discovered that a hydrogen radical treatment is used to strip or reduce the oxide from the film. This reduction leaves Ti atoms in the lattice framework. The metal oxide or metal oxynitride layer may have about 2% to about 60% oxygen atoms by weight before the reduction reaction and about 5% to about 50% oxygen atoms by weight after the reduction reaction. The reduction reaction is described below in step 208. Additionally, in some applications, nitrogen is added back into the framework to maintain the chemical composition and properties of TiN, as described below with reference to step 210. Devices using metal films, such as Ti films, are processed as described in steps 206 and 208. Devices using metal nitride films, such as TiN films, are processed as described in steps 206, 208, and 210 below.

[0026]

[0031] In step 208, the metal oxide or metal oxynitride is exposed to hydrogen radicals while converting the metal oxide or metal oxynitride to a metal fill layer 332, so that the seam is at least partially filled with the metal fill layer 332. A substrate 304 having a seam substantially filled with a metal film layer 332 is shown in FIG. 3B. For devices using a metal film, such as a Ti film, the seam is substantially filled with the metal fill layer 332. In some embodiments, which can be combined with other embodiments, the metal fill layer 332 of the film, such as a metal film, is substantially free of seams. In some embodiments, which can be combined with other embodiments, the metal fill layer 332 of the film may have a seam that is less than about half, or less than about ¼, or less than about 10% of the seam width 114 before exposing the film. In one example, the seam width of the metal fill layer 332 of the film is less than about 1 Å. In particular, no seams are observed in transmission electron microscope ("TEM") images. For metal nitride films, the seam after exposure to hydrogen radicals is larger than the atomic diameter of nitrogen so that nitrogen atoms can penetrate into the seam. In particular, for metal nitride films, the seam width after reduction is larger than 1.6 Å, e.g., from about 1.6 Å to about 5 Å, e.g., from 2 Å to about 5 Å.

[0027]

[0032] Step 208 is performed in the same processing chamber as step 206, such as the first processing chamber or the second processing chamber. However, it is contemplated that in some embodiments step 208 may be performed in a different processing chamber than step 206. The temperature is maintained at a temperature of at least 300° C., such as from about 300° C. to about 1000° C., such as from about 400° C. to about 650° C., such as from about 400° C. to about 500° C., such as about 450° C. The second processing region is maintained at less than atmospheric pressure during processing. The pressure in step 208 is maintained at about 0.2 torr to about 5 torr, such as from about 0.3 torr to about 5 torr, such as from about 0.5 torr to about 5 torr, such as from about 2 torr to about 4 torr, such as about 3 torr, such as about 1 torr, or about 2 torr.

[0028]

[0033] The hydrogen radicals in step 208 are formed outside the processing region and flowed into the processing region, or the hydrogen radicals are formed inside the processing region. For hydrogen radicals formed outside the processing region, the hydrogen radicals are formed in a plasma source. The plasma source is selected from a remote plasma source, which may be either an inductively coupled plasma source or a microwave plasma source. The plasma source includes an excitation source, such as a radio frequency (RF) source. In step 208, the RF power applied by the RF source is about 2 kW to about 10 kW, such as about 7 kW to about 9 kW, for example, about 8 kW. The hydrogen radicals are formed from hydrogen gas. The film is exposed to the hydrogen radicals for about 100 seconds to about 600 seconds, for example, about 100 seconds to about 300 seconds, for example, about 150 seconds.

[0029]

[0034] In some embodiments, which may be combined with other embodiments, hydrogen radicals are introduced into the processing chamber with a second gas. The second gas is selected from argon (Ar), krypton (Kr), xenon (Xe), nitrogen (N), helium (He), neon (Ne), or any combination thereof. The hydrogen radicals are introduced into the processing region at a flow rate of about 0.1 slm to about 10 slm, such as about 0.1 slm to about 5 slm, such as about 0.1 slm to about 1 slm, such as about 0.3 slm to about 0.4 slm, such as about 0.35 slm.

[0030]

[0035] Although the above embodiments describe the formation of hydrogen radicals using a remote plasma source, it is contemplated that hydrogen radicals can be generated in situ (e.g., in a processing chamber). In such an example, hydrogen gas is introduced into the processing region, and hydrogen (H2) molecules are dissociated into hydrogen radicals by applying a voltage to the hydrogen molecules with an RF source. A component of a second gas, such as argon gas, facilitates the dissociation of hydrogen into hydrogen radicals. In at least one example, the hydrogen radicals flowing into the processing chamber are about 2% to about 100% by volume of the total gas flowing into the processing region. In step 208, argon gas can flow into the processing region at a rate of about 0.1 slm to about 10 slm, such as about 1 slm to about 6 slm, such as about 2 slm to about 4 slm, such as about 3 slm, or about 3.15 slm, or about 4 slm. In at least one example, the argon gas flowing into the processing chamber in step 208 is from about 0% to about 98% by volume of the total gas flowing into the processing region in step 208 .

[0031]

[0036] In optional step 210 , the metal fill layer 332 is exposed to nitrogen radicals while converting the metal fill layer 332 to a metal nitride layer 342 such that the seam is substantially filled with the metal nitride layer 342 .

[0032]

[0037] A substrate 304 having a metal nitride layer 342 is shown in FIG. 3C. The metal nitride layer 342 of the film is substantially seam-free. In some embodiments, which can be combined with other embodiments, the metal nitride layer 342 of the film may have a seam having a width that is less than about half, or less than about a quarter, or less than about 10% of the seam width 114 before exposing the film in steps 206 through 210. The seam width of the metal nitride layer 342 of the film is less than about 1 Å. Notably, no seams are observed in transmission electron microscope ("TEM") images.

[0033]

[0038] Step 210 is performed in the same processing chamber as steps 206 and / or 208, such as a first process chamber or a second processing chamber. However, it is contemplated that step 210 may be performed in a different processing chamber than steps 206 and / or 208. During step 210, the temperature is maintained at a temperature of at least 300° C., such as from about 300° C. to about 1000° C., such as from about 400° C. to about 650° C., such as from about 400° C. to about 500° C., such as about 450° C. The pressure in step 210 is maintained at about 0.2 torr to about 5 torr, such as from about 0.3 torr to about 5 torr, such as from about 0.5 torr to about 5 torr, such as from about 2 torr to about 4 torr, such as about 3 torr, such as about 1 torr, or about 2 torr.

[0034]

[0039] The nitrogen radicals in step 210 are formed in a plasma source, such as a remote plasma source, including an inductively coupled plasma source or a microwave plasma source. The plasma source includes an excitation source, such as radio frequency (RF), to promote radical generation. In step 210, the RF power provided by the RF source is about 6 kW to about 10 kW, such as about 7 kW to about 9 kW, such as about 8 kW. The nitrogen radicals are formed outside the processing region and flowed into the processing region. The nitrogen radicals are formed from a nitrogen-containing gas, such as nitrogen gas and / or ammonia gas and / or N2H4. The film is exposed to the nitrogen radicals for about 100 seconds to about 600 seconds, such as about 100 seconds to about 300 seconds, such as about 150 seconds.

[0035]

[0040] In some embodiments, which can be combined with other embodiments, the nitrogen radicals are introduced into the processing chamber together with a third gas, which is selected from an argon-containing gas, a nitrogen-containing gas, and combinations thereof, such as ammonia gas, such as nitrogen gas.

[0036]

[0041] While the above embodiment generates radicals with a remote plasma source, it is also contemplated that nitrogen radicals may be generated in situ. It is further contemplated that imidogens (e.g., NH radicals) may be generated. In such an example, a nitrogen-containing gas may be introduced into the processing region, and nitrogen-containing molecules (e.g., N2, NH3) may be energized with an RF source to dissociate into nitrogen radicals within the processing region. A component of a third gas, e.g., argon gas, a nitrogen-containing gas, facilitates the dissociation of nitrogen into nitrogen radicals.

[0037]

[0042] The nitrogen radicals are introduced into the processing region at a flow rate of about 0.1 slm to about 10 slm, such as about 0.1 slm to about 5 slm, such as about 0.1 slm to about 1 slm, such as about 0.3 slm to about 0.6 slm, such as about 0.5 slm. The nitrogen radicals are introduced into the processing region with a third gas, such as argon gas. The argon gas may flow into the processing region at a rate of about 0.1 slm to about 10 slm, such as about 1 slm to about 6 slm, such as about 2 slm to about 4 slm, such as about 3 slm, or about 4 slm. In at least one example, the nitrogen radicals flowing into the processing chamber are about 5% to about 100% by volume of the total gas flowing into the processing region. In another example, the argon gas flowing into the processing chamber is about 0% to about 95% by volume of the total gas flowing into the processing region in step 210.

[0038]

[0043] In some embodiments, which can be combined with other embodiments, the third gas can include ammonia gas. The ammonia gas can flow into the processing region at a rate of about 0.1 slm to about 10 slm, for example, about 0.1 slm to about 0.6 slm, for example, about 0.2 slm to about 0.4 slm, for example, about 0.2 slm, or about 0.3 slm. In at least one example, the ammonia gas flowing into the processing chamber in step 210 is about 0% to about 95% by volume of the total gas flowing into the processing region in step 210.

[0039]

[0044] In some embodiments, which can be combined with other embodiments, depositing the film (e.g., step 204), heating the film, and exposing the film to the radical species (e.g., steps 206, 208, and / or 210) are performed in a single chamber. In some embodiments, which can be combined with other embodiments, exposing the film to each radical species is sequential, with each of the radical species being pulsed alternately into the processing region. Alternatively, in other embodiments, exposing the film to each radical species is performed simultaneously, with each radical species being flowed into the processing region in succession.

[0040]

[0045] During processing, heaters or coolers disposed on the substrate support can conductively control the substrate temperature. The substrate can also be heated convectively by heaters or coolers positioned proximate to the substrate. Gases employed in the present disclosure may also be heated or cooled to locally vary the substrate temperature.

[0041]

[0046] The particular features, structures, compositions, materials, or characteristics described herein may be combined in any suitable manner in one or more embodiments. Although the present disclosure has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present disclosure. It will be apparent to those skilled in the art that various modifications and variations can be made to the methods and systems of the present disclosure. Thus, the present disclosure is intended to cover modifications and variations that come within the scope of the appended claims and their equivalents.

Claims

1. A method for processing a substrate, comprising the steps of: positioning the substrate in a processing chamber including a processing region, the substrate having at least one feature extending in a depth direction from a substrate surface to a bottom surface, the at least one feature having an interior sidewall surface; forming a film comprising a metal-containing material on a surface of the substrate and an interior sidewall surface of the at least one feature, and a bottom surface of the at least one feature, the film having a seam therein, the seam having a seam width; heating the substrate at a temperature between 300° C. and 1000° C.; exposing the film in the seam to oxygen radicals while converting a metal-containing material of the film to a metal oxide or metal oxynitride material, wherein the seam is at least partially filled with the metal oxide or metal oxynitride material; and exposing the metal oxide or metal oxynitride material to hydrogen radicals while converting the metal oxide or metal oxynitride material into a metal-containing filler layer; exposing the metal-containing packing bed to nitrogen radicals while converting the metal-containing packing bed into a metal nitride layer, wherein the metal nitride layer is seamless; The method includes:

2. The method of claim 1 , wherein exposing the film to oxygen radicals comprises dissociating diatomic oxygen gas to produce oxygen radicals.

3. Exposing the film to oxygen radicals includes ２ , Ar, Kr, Xe, N ２ 3. The method of claim 2, comprising flowing diatomic oxygen gas with a first gas selected from the group consisting of He, Ne, and combinations thereof.

4. exposing the film to oxygen radicals includes flowing diatomic oxygen gas into a processing region at 0.1 slm to 10 slm; 3. The method of claim 2, wherein exposing the metal oxide or metal oxynitride material-containing film to hydrogen radicals comprises flowing a hydrogen-containing gas into the processing region at a rate of 0.1 slm to 10 slm.

5. The method of claim 2 , wherein dissociating the diatomic oxygen gas occurs within the processing region.

6. 6. The method of claim 5, wherein dissociating the diatomic oxygen gas comprises applying an excitation source to the diatomic oxygen gas in the processing region, the excitation source having a radio frequency (RF) power of 6 kW to 10 kW.

7. exposing the film to oxygen radicals comprises exposing the film to oxygen radicals for 100 seconds to 400 seconds; 10. The method of claim 1, wherein exposing the metal oxide comprises exposing the metal oxide to hydrogen radicals for 100 to 400 seconds.

8. 10. The method of claim 1, wherein the metal-containing material of the film comprises Ta, Ti, W, Cr, Co, Al, Cu, Mo, Rb, TaN, TiN, WN, CrN, AlN, RbN, alloys thereof, or combinations thereof.

9. Exposing the metal oxide or metal oxynitride material to hydrogen radicals may be accomplished by using a hydrogen-containing gas such as Ar, Kr, Xe, N ２ 10. The method of claim 1 , comprising co-flowing with a second gas selected from the group consisting of He, Ne and combinations thereof.

10. 10. The method of claim 1, wherein exposing the metal-containing packing bed to nitrogen radicals comprises exposing the metal-containing packing bed to nitrogen radicals for 100 to 400 seconds.

11. The method of claim 10 , wherein exposing the metal-containing fill bed to nitrogen radicals comprises dissociating a nitrogen-containing gas into nitrogen radicals.

12. The method of claim 1 , wherein the processing region is maintained at a pressure between 0.5 Torr and 5 Torr.

13. A method for processing a substrate, comprising the steps of: Positioning the substrate in a processing chamber including a processing region, the substrate comprising: at least one feature extending in a depth direction from the substrate surface to a bottom surface and having an inner sidewall surface; a membrane comprising a metal material or a metal nitride material disposed along an interior sidewall surface of the at least one feature and a bottom surface of the at least one feature, the membrane having a seam therein along a depth direction of the feature; positioning the substrate in a processing chamber including a processing region; exposing the film in the seam to oxygen radicals while converting the metal material to a metal oxide or converting the metal nitride material to a metal oxynitride material, wherein the seam is at least partially filled with the metal oxide or metal oxynitride material; exposing the film in the seam to oxygen radicals while converting the metal material to a metal oxide or converting the metal nitride material to a metal oxynitride material; exposing the metal oxide or metal oxynitride material to hydrogen radicals while converting the metal oxide to a metal filled layer or converting the metal oxynitride material to a metal nitride filled layer; exposing the metal fill layer or the metal nitride fill layer to nitrogen radicals, imidogens, or a combination thereof to convert the metal fill layer or the metal nitride fill layer into a seamless metal nitride fill layer; The method includes:

14. The method of claim 13 , wherein the at least one feature has an aspect ratio of 5:1 or greater.

15. 14. The method of claim 13, wherein a seam width before exposing the film is between 2 Å and 10 Å and a seam width after exposing the film is less than 2 Å.

16. A method for processing a substrate, comprising the steps of: positioning the substrate in a first processing chamber including a first processing region, the substrate having at least one feature extending in a depth direction from a substrate surface to a bottom surface, the at least one feature having an interior sidewall surface; forming a film comprising a metal-containing material on the substrate surface and the interior sidewall surface and a bottom surface of the at least one feature, the film having a seam therein having a seam width; Positioning the substrate in a second processing chamber including a second processing region; heating the film at a temperature of 400° C. to 650° C.; exposing the film in the seam to oxygen radicals while converting a metal-containing material of the film to a metal oxide, wherein the seam is at least partially filled with the metal oxide; exposing the film in the seam to oxygen radicals while converting a metal-containing material of the film to a metal oxide; exposing the metal oxide to hydrogen radicals while converting the metal oxide into a metal fill layer; exposing the metal fill bed to nitrogen radicals to convert the metal fill bed to a metal nitride fill bed; The method includes:

17. 17. The method of claim 16, wherein the seam width of the film before heating and exposing the film is between 2 Å and 10 Å and the seam width after heating and exposing the film is less than 2 Å.

18. 20. A system including an algorithm stored in a memory of the system, said algorithm including a number of instructions that, when executed by a processor, causes the system to perform the method of claim 16.

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