Gap-filling with aluminum film

Abstract

The method of depositing a film includes depositing an aluminum-containing gap-fill film in a feature on a substrate surface in a bottom-up manner. The substrate may be exposed to an aluminum-containing precursor, a reactant, a fluorinating agent, and an etchant any number of times to promote bottom-up growth of the film in the feature.

Description

Technical Field

[0001] The present disclosure generally relates to methods of depositing thin films. In particular, the present disclosure relates to a gap-fill process for filling narrow trenches. Background Art

[0002] In microelectronic device manufacturing, narrow trenches with an aspect ratio (AR) of about 5:1 or greater need to be filled without voids for many applications. One application is patterning. Other applications include, but are not limited to: memory capacitors (DRAM, flash memory, ReRAM, MIM capacitors), dielectric films for controlling switch gates (transistors), optical functional films (optical isolation), and mechanical films (virtual gates) that support circuit structures.

[0003] Aluminum oxide and other aluminum-based films such as aluminum nitride have a low dry etching rate compared to typical dielectric films such as SiO, SiN, SiCN, and Si.

[0004] What is needed is a method for gap-filling using aluminum-based films resulting in bottom-up film growth where the as-deposited film is of high quality with minimal to no voids. Summary of the invention

[0005] One or more embodiments of the present disclosure are directed to a processing method that includes depositing an aluminum-containing gap-fill film in a feature on a substrate surface, the feature extending from the substrate surface to a bottom surface, at least one feature having a width defined by a first sidewall and a second sidewall, in a bottom-up manner.

[0006] Additional embodiments of the present disclosure relate to a processing method, the processing method comprising: positioning a substrate surface in a processing chamber. The substrate surface has at least one feature. The at least one feature creates a gap having a bottom, a top, and sidewalls. The substrate surface is exposed to an aluminum-containing precursor and a reactant to form a conformal aluminum-containing film on the substrate surface. The substrate surface is exposed to a fluorinating agent and an etchant to preferentially etch the conformal aluminum-containing film at the top of the feature relative to the bottom of the feature. After the preferential etching, the substrate surface is optionally exposed to an oxidant. The gap of the feature is filled in a bottom-up manner by sequentially exposing to the precursor and the reactant, and then to the fluorinating agent and the etchant and the optional oxidant.

[0007] Other embodiments of the disclosure are directed to a processing method, comprising: placing a substrate having a substrate surface into a processing chamber comprising a plurality of sections, each section being separated from an adjacent section by a gas curtain, the substrate surface having at least one feature, the at least one feature having a top, a bottom, and a side, and having an aspect ratio greater than or equal to 10:1. At least a portion of the substrate surface is exposed to a first process condition in a first section of the processing chamber, the first process condition comprising an aluminum-containing precursor. The substrate surface is moved laterally through the gas curtain to a second section of the processing chamber. The substrate surface is exposed to a second process condition in the second section of the processing chamber, the second process condition comprising a reactant that forms a film with the aluminum-containing precursor, the film comprising an AlC x O y N z wherein x, y, and z are independently in the range of 0-3. The substrate surface is moved laterally through the gas curtain to a third portion of the processing chamber. The substrate surface is exposed to a third process condition in the third portion of the processing chamber, the third process condition comprising a fluorinating agent. The substrate surface is moved through the gas curtain to a fourth portion of the processing chamber. The substrate surface is exposed to a fourth process condition in the fourth portion of the processing chamber, the fourth process condition comprising an etchant. Optionally, the substrate surface is moved through the gas curtain to a fifth portion of the processing chamber. Optionally, the substrate surface is exposed to a fifth process condition in the fifth portion of the processing chamber, the fifth process condition comprising an oxidant. Repeated exposure to the first portion, the second portion, the third portion, the fourth portion, and optionally the fifth portion including lateral movement of the substrate surface to fill the feature. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The above briefly summarizes the manner in which the above-described features of the present disclosure can be understood in detail, as well as a more specific description of the present disclosure, which can be obtained by referring to the embodiments, some of which are illustrated in the accompanying drawings. However, it should be noted that the drawings illustrate only typical embodiments of the present disclosure and are therefore not to be considered limiting of its scope, as the disclosure may admit to other equally effective embodiments.

[0009] Figure 1 shows a cross-sectional view of a batch processing chamber according to one or more embodiments of the disclosure;

[0010] Figure 2 shows a partial perspective view of a batch processing chamber according to one or more embodiments of the disclosure;

[0011] Figure 3 A schematic diagram of a batch processing chamber according to one or more embodiments of the disclosure is shown;

[0012] Figure 4A schematic diagram showing a portion of a wedge-shaped gas distribution assembly for use in a batch processing chamber according to one or more embodiments of the disclosure;

[0013] Figure 5 A schematic diagram of a batch processing chamber according to one or more embodiments of the disclosure is shown;

[0014] Figure 6 shows a cross-sectional view of a substrate feature according to one or more embodiments of the disclosure;

[0015] Figure 7 A process flow diagram illustrating a bottom-up gap-fill process according to one or more embodiments of the disclosure;

[0016] Figures 8A to 8F A gap-fill process according to one or more embodiments of the disclosure is shown;

[0017] Fig. 9 is a schematic diagram of an etching process from a molecular perspective according to one embodiment;

[0018] Fig.10 shows the thickness according to one or more embodiments of the disclosure Relationship diagram with temperature (℃);

[0019] Fig.11 shows the growth and A plot of the etching per unit as a function of the NF3 pulse;

[0020] Fig.12 The etching rate ( / cycle) as a function of TMA pulse;

[0021] Fig.13 shows the thickness according to one or more embodiments of the disclosure Plot as a function of the number of cycles;

[0022] Fig.14A -B provides a scanning electron microscope (SEM) image of a 10:1 aspect ratio structure with trench features as a comparative example; and

[0023] Fig.15A -B provides a scanning electron microscope (SEM) image of a 10:1 aspect ratio structure having trench features after performing multiple cycles according to one or more embodiments of the disclosure. DETAILED DESCRIPTION

[0024] Before describing several exemplary embodiments of the disclosure, it should be understood that the disclosure is not limited to the details of construction or process steps set forth in the following description. The disclosure is capable of other embodiments and can be practiced or carried out in various ways.

[0025] As used herein, "substrate" refers to any substrate or material surface formed on a substrate on which film processing is performed in a manufacturing process. For example, depending on the application, the substrate surface on which processing can be performed includes: 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. Substrates include, but are not limited to, semiconductor wafers. The substrate can be exposed to a pretreatment process to polish, etch, reduce, oxidize, hydroxylate, anneal and / or bake the substrate surface. In addition to performing film processing directly on the surface of the substrate itself, in the present disclosure, any film processing step disclosed can also be performed on an underlying layer formed on the substrate, as disclosed in more detail below, and the term "substrate surface" is intended to include the above-mentioned underlying layer as indicated by the context. Thus, for example, in the case where a film / layer or a portion of a film / layer has been deposited on the substrate surface, the exposed surface of the newly deposited film / layer becomes the substrate surface.

[0026] Aluminum oxide (AlO) is used for patterning applications. AlO has a lower dry etch rate than typical dielectric films such as SiO, SiN, SiCN, and Si. Therefore, for bottom-up gap-filling of substrate features, AlO has good etch selectivity compared to other films. In addition to AlO, suitable gap-fill films include the following, which include but are not limited to: AlN, AlC, AlCN, metallic Al, and the like, commonly referred to as AlC x O y N z , wherein x, y and z are independently in the range of 0-3 depending on the nature of the atomic species. As will be appreciated by those skilled in the art, AlC x O y N z It is not intended to be stoichiometric, but rather a representation of atomic composition, where x, y, and z are independently in the range of 0-1. For example, a stoichiometric film of Al2O3 may be referred to as AlCOO 1.5 N0. The above films may also be referred to by atomic composition rather than stoichiometry - such as aluminum carbide, aluminum oxide, aluminum nitride, aluminum oxycarbide, aluminum oxynitride, aluminum carbonitride and / or aluminum oxycarbonitride.

[0027] One or more embodiments of the disclosure relate to a processing method comprising depositing an aluminum-containing gap-fill film in a feature on a substrate in a bottom-up manner. In this regard, the term "bottom-up manner" refers to the film being preferentially deposited at the bottom of the feature relative to the top of the feature. The method herein is directed to non-conformal etching, wherein the etch rate at the top of the feature is higher than the etch rate at the bottom of the feature.

[0028] One or more embodiments of the disclosure relate to methods of preferentially etching the top of a feature relative to the bottom of the feature, followed by film deposition, thereby growing the film in a bottom-up manner. Certain embodiments of the disclosure provide methods of advantageously filling features with aspect ratios greater than 5:1 or even 10:1 with films. One or more embodiments of the disclosure advantageously provide methods of gap-filling features with high throughput and repeatability.

[0029] According to one or more embodiments, the method uses a chemical vapor deposition (CVD) process. In the above embodiments, the substrate surface is simultaneously exposed to the first reactive gas and the second reactive gas to mix the first reactive gas and the second reactive gas during film formation.

[0030] According to one or more embodiments, the method uses an atomic layer deposition (ALD) process. In the above embodiments, the substrate surface is exposed to the precursor (or reactive gas) sequentially or substantially sequentially. Throughout the specification, "substantially sequentially" means that the majority of the time of exposure of the precursor does not overlap with the exposure of the common reactant, although there may be some overlap. As used in this specification and the appended claims, the terms "precursor", "reactant", "reactive gas" and similar terms are used interchangeably to refer to any gaseous substance that can react with the substrate surface, or a substance present on the substrate surface.

[0031] In one or more embodiments, the gap-filling method is performed using an atomic layer deposition (ALD) process. The ALD process is a self-limiting process in which a single layer of material is deposited using a binary (or higher order) reaction. In theory, a single ALD reaction is self-limiting until all available active sites on the substrate surface react. The ALD process can be performed by time domain or spatial ALD.

[0032] In a time domain process, the process chamber and substrate are exposed to a single reactive gas at any given time. In an exemplary time domain process, a metal precursor may be filled in the process chamber for a period of time to allow the metal precursor to fully react with the available sites on the substrate. The precursor may then be purged from the process chamber before a second reactive gas is flowed into the process chamber and allowed to fully react with the substrate surface or material on the substrate surface. Time domain processes minimize the mixing of reactive gases by ensuring that only one reactive gas is present in the process chamber at any given time. At the beginning of any reactive gas exposure, there is a delay in which the concentration of the reactive species increases from zero to a final predetermined pressure. Likewise, there is a delay in clearing all reactive species from the process chamber.

[0033] In a spatial ALD process, the substrate moves between different process zones within a single processing chamber. Each individual process zone is separated from adjacent process zones by a gas curtain. The gas curtain helps prevent the reactive gases from mixing, thereby minimizing any gas phase reactions. The movement of the substrate through the different process zones allows the substrate to be sequentially exposed to different reactive gases while preventing gas phase reactions.

[0034] Certain embodiments of the disclosure are directed to film deposition processes using a batch processing chamber, also referred to as a space processing chamber. Figure 1 A cross section of a processing chamber 100 is shown including a gas distribution assembly 120, also referred to as an injector or injector assembly, and a susceptor assembly 140. The gas distribution assembly 120 is any type of gas delivery assembly used in a processing chamber. The gas distribution assembly 120 includes a front surface 121 facing the susceptor assembly 140. The front surface 121 may have any number or type of openings to deliver a gas flow toward the susceptor assembly 140. The gas distribution assembly 120 also includes an outer edge 124, which is substantially circular in the embodiment shown.

[0035] The specific type of gas distribution assembly 120 used may vary depending on the specific process used. Embodiments of the disclosure may be used with any type of processing system that controls the gap between the susceptor and the gas distribution assembly. In a binary reaction, the plurality of gas channels may include at least one first reactive gas A channel, at least one second reactive gas B channel, at least one purge gas P channel, and / or at least one vacuum V channel. The gases flowing out of the first reactive gas A channel, the second reactive gas B channel, and the purge gas P channel are directed to the top surface of the wafer. Some gas flows move in a horizontal direction across the surface of the wafer and leave the processing area through the purge gas P channel.

[0036] In some embodiments, the gas distribution assembly 120 is a rigid fixed body made of a single injector unit. In one or more embodiments, the gas distribution assembly 120 is composed of multiple separate sectors (e.g., injector units 122), such as Figure 2 A single piece body or a multi-sector body may be used with the various embodiments of the disclosed content described.

[0037] The pedestal assembly 140 is located below the gas distribution assembly 120. The pedestal assembly 140 includes a top surface 141 and at least one recess 142 in the top surface 141. The pedestal assembly 140 also has a bottom surface 143 and an edge 144. The recess 142 can be of any suitable shape and size, depending on the shape and size of the substrate 60 being processed. Figure 1 In the illustrated embodiment, the recess 142 has a flat bottom to support the bottom of the wafer; however, the bottom of the recess may vary. In some embodiments, the recess has a stepped area around the peripheral edge of the recess that is sized to support the peripheral edge of the wafer. The amount of the peripheral edge of the wafer that is supported by the step can vary depending on, for example, the thickness of the wafer and the features that already exist on the back side of the wafer.

[0038] In certain embodiments, Figure 1 As shown, the recess 142 in the top surface 141 of the susceptor assembly 140 is sized so that the substrate 60 supported in the recess 142 has a top surface 61 that is substantially coplanar with the top surface 141 of the susceptor 140. As used in this specification and the appended claims, the term "substantially coplanar" means that the top surface of the wafer and the top surface of the susceptor assembly are coplanar within ±0.2 mm. In some embodiments, the top surfaces are coplanar within ±0.15 mm, within ±0.10 mm, or within ±0.05 mm.

[0039] Figure 1 The pedestal assembly 140 includes a support column 160 that can lift, lower, and rotate the pedestal assembly 140. The pedestal assembly may include a heater, or gas lines, or electrical components within the center of the support column 160. The support column 160 may be the primary means of increasing or decreasing the gap between the pedestal assembly 140 and the gas distribution assembly 120, and moving the pedestal assembly 140 into position. The pedestal assembly 140 may also include a fine adjustment actuator 162 that can fine-tune the pedestal assembly 140 to create a predetermined gap 170 between the pedestal assembly 140 and the gas distribution assembly 120.

[0040] In certain embodiments, the gap 170 distance is in the range of about 0.1 mm to about 5.0 mm, or in the range of about 0.1 mm to about 3.0 mm, or in the range of about 0.1 mm to about 2.0 mm, or in the range of about 0.2 mm to about 1.8 mm, or in the range of about 0.3 mm to about 1.7 mm, or in the range of about 0.4 mm to about 1.6 mm, or in the range of about 0.5 mm to about 1.5 mm, or in the range of about 0.6 mm to about 1.4 mm, or in the range of about 0.7 mm to about 1.3 mm, or in the range of about 0.8 mm to about 1.2 mm, or in the range of about 0.9 mm to about 1.1 mm, or is about 1 mm.

[0041] The processing chamber 100 shown in the figure is a turntable chamber, wherein the base assembly 140 can accommodate a plurality of substrates 60. Figure 2 As shown, the gas distribution assembly 120 may include a plurality of separate injector units 122, each injector unit 122 being capable of depositing a film on a wafer when the wafer moves under the injector unit. Two fan-shaped injector units 122 are shown, and the two fan-shaped injector units 122 are positioned on and above approximately opposite sides of the base assembly 140. The number of the injector units 122 shown is for exemplary purposes only. It should be understood that more or fewer injector units 122 may be included. In some embodiments, a sufficient number of fan-shaped injector units 122 are formed to conform to the shape of the base assembly 140. In some embodiments, each individual fan-shaped injector unit 122 may be independently moved, removed and / or replaced without affecting any other injector unit 122. For example, a segment may be lifted to allow a robot to enter the area between the base assembly 140 and the gas distribution assembly 120 to load / unload the substrate 60.

[0042] A processing chamber with multiple gas injectors can be used to process multiple wafers simultaneously, so that the wafers undergo the same process flow. Figure 3As shown in , the processing chamber 100 has four gas injector assemblies and four substrates 60. At the beginning of the process, the substrate 60 can be placed between the injector assemblies 30. Rotating the pedestal assembly 140 45° will move each substrate 60 located between the gas distribution assemblies 120 to the gas distribution assembly 120 for film deposition, as shown by the dashed circle under the gas distribution assembly 120. An additional 45° rotation will move the substrate 60 away from the injector assembly 30. The number of substrates 60 and gas distribution assemblies 120 can be the same or different. In some embodiments, the number of wafers processed is the same as the number of gas distribution assemblies. In one or more embodiments, the number of wafers processed is a fraction or integer multiple of the number of gas distribution assemblies. For example, if there are four gas distribution assemblies, 4x wafers are processed, where x is an integer greater than or equal to 1. In an exemplary embodiment, the gas distribution assembly 120 includes eight processing areas separated by gas curtains, and the pedestal assembly 140 can accommodate six wafers.

[0043] Figure 3 The process chamber 100 shown in the figures is representative of only one possible configuration and should not be considered as limiting the scope of the present disclosure. Here, the process chamber 100 includes a plurality of gas distribution assemblies 120. In the illustrated embodiment, there are four gas distribution assemblies (also referred to as injector assemblies 30) evenly spaced about the process chamber 100. The process chamber 100 is shown as an octagon; however, those skilled in the art will appreciate that this is one possible shape and should not be considered as limiting the scope of the present disclosure. The gas distribution assembly 120 is shown as being trapezoidal, but could also be a single circular component, or could also be as shown in FIG. Figure 2 As shown, it is generally composed of multiple fan-shaped segments.

[0044] Figure 3 The illustrated embodiment includes a load lock chamber 180, or an auxiliary chamber similar to a buffer station. This chamber 180 is connected to one side of the processing chamber 100 to allow, for example, loading / unloading of substrates (also referred to as substrates 60) from the chamber 100. A wafer robot may be placed in the chamber 180 to move the substrates onto the susceptor.

[0045] The rotation of the turntable (e.g., pedestal assembly 140) can be continuous or intermittent (discontinuous). In continuous processing, the wafers are rotated continuously so that they are exposed to each injector in turn. In discontinuous processing, the wafers can be moved to the injector area and stopped, then moved to the area 84 between injectors and stopped. For example, the turntable can be rotated so that the wafer moves from the area between injectors through the injectors (or stops near the injectors), and then moves to the area between the next injectors, where the turntable can be paused again. The pause between injectors may provide time for additional processing (e.g., exposure to plasma) between each layer deposition.

[0046] Figure 4 A sector or portion of the gas distribution assembly 220 is shown, which may be referred to as an injector unit 122. The injector unit 122 may be used alone or in combination with other injector units. Figure 5 As shown, four Figure 4 The injector units 122 are combined to form a single gas distribution assembly 220. (For clarity, the lines separating the four injector units are not shown.) Figure 4 The injector unit 122 has the first reactive gas port 125 and the second gas port 135 in addition to the purge gas port 155 and the vacuum port 145 , but the injector unit 122 does not need all of these components.

[0047] Reference Figure 4 and Figure 5 Both, the gas distribution assembly 220 according to one or more embodiments may include a plurality of sectors (or injector units 122), each of which is the same or different. The gas distribution assembly 220 is located within the processing chamber and includes a plurality of elongated gas ports 125, 135, 155 and an elongated vacuum port 145 in the front surface 121 of the gas distribution assembly 220. The plurality of elongated gas ports 125, 135, 155 and the elongated vacuum port 145 extend from an area adjacent to the inner peripheral edge 123 of the gas distribution assembly 220 to an area adjacent to the outer peripheral edge 124 of the gas distribution assembly 220. The plurality of gas ports shown include a first reactive gas port 125, a second gas port 135, a vacuum port 145 surrounding each of the first reactive gas port and the second reactive gas port, and a purge gas port 155.

[0048] Reference Figure 4 or Figure 5 In the illustrated embodiment, when the port is described as extending from at least near the inner peripheral region to at least near the outer peripheral region, the port may not only extend radially from the inside to the outside. When the vacuum port 145 surrounds the reactive gas port 125 and the reactive gas port 135, the port may extend tangentially. Figure 4 and 5 In the illustrated embodiment, the wedge-shaped reactive gas ports 125, 135 are surrounded by vacuum ports 145 on all edges including the edges adjacent the inner peripheral region and the outer peripheral region.

[0049] Reference Figure 4 As the substrate moves along path 127, each portion of the substrate surface is exposed to multiple reactive gases. To follow path 127, the substrate will be exposed to or "see" purge gas port 155, vacuum port 145, first reactive gas port 125, vacuum port 145, purge gas port 155, vacuum port 145, second gas port 135, and vacuum port 145. Thus, in Figure 4 At the end of the path 127 shown in FIG. 1 , the substrate has been exposed to the first gas port 125 and the second gas port 135 to form a layer. The injector unit 122 is shown as a quarter turn, but can be larger or smaller. Figure 5 The gas distribution assembly 220 shown in FIG. 2 can be viewed as four Figure 4 A combination of the injector units 122 connected in series.

[0050] Figure 4 The injector unit 122 of FIG. 1 shows a gas curtain 150 that separates the reactive gases. The term "gas curtain" is used to describe any combination of gas flow or vacuum that separates the reactive gases to prevent mixing. Figure 4 The gas curtain 150 shown includes a portion of the vacuum port 145 near the first reactive gas port 125, a purge gas port 155 in the middle, and a portion of the vacuum port 145 near the second gas port 135. This combination of gas flow and vacuum can be used to prevent or minimize gas phase reactions of the first reactive gas and the second reactive gas.

[0051] Reference Figure 5 The combination of gas flow and vacuum from the gas distribution assembly 220 forms a separation into a plurality of processing areas 250. The processing areas 250 are generally defined around the individual gas ports 125, 135, and the gas curtains 150 are located between the processing areas. Figure 5 The illustrated embodiment provides eight separate processing zones 250 with eight separate gas curtains 150 therebetween. The processing chamber may have at least two processing zones. In certain embodiments, there are at least three, four, five, six, seven, eight, nine, 10, 11, or 12 processing zones.

[0052] During processing, the substrate may be exposed to more than one processing region 250 at any given time. However, the portions exposed to different processing regions will have a gas curtain separating the two. For example, if the leading edge of the substrate enters the processing region including the second gas port 135, the middle portion of the substrate will be located under the gas curtain 150, and the trailing edge of the substrate will be located in the processing region including the first reactive gas port 125.

[0053] A factory interface 280, which may be a load lock chamber, is shown connected to the processing chamber 100. The substrate 60 is shown superimposed on the gas distribution assembly 220 to provide a frame of reference. The substrate 60 may generally sit on a pedestal assembly to be secured adjacent the front surface 121 of the gas distribution assembly 120. The substrate 60 is loaded into the processing chamber 100 via the factory interface 280 onto a substrate support or pedestal assembly (see Figure 3 ). The substrate 60 can be shown as being within the processing region because the substrate is located near the first reactive gas port 125 and between the two gas curtains 150a, 150b. Rotating the substrate 60 along the path 127 will move the substrate counterclockwise around the processing chamber 100. Therefore, the substrate 60 will be exposed to the first processing region 250a to the eighth processing region 250h, including all processing regions between the first processing region 250a and the eighth processing region 250h.

[0054] The processing method of the embodiment of the disclosure includes a processing chamber 100 having a plurality of processing regions 250a-250h, wherein each processing region is separated from an adjacent region by a gas curtain 150. For example, Figure 5 The number of air curtains and processing zones within the processing chamber may be any suitable number, depending on the arrangement of the airflow. Figure 5 The illustrated embodiment has eight air curtains 150 and eight processing zones 250a-250h. The number of air curtains is typically equal to or greater than the number of processing zones.

[0055] A plurality of substrates 60 are located on a substrate support, such as a Figure 1 and Figure 2 Substrate assembly 140 is shown. Multiple substrates 60 are rotated around the processing area for processing. Typically, the gas curtain 150 is engaged (gas flowing and in a vacuum state) during the entire processing period, including the period when no reactive gas flows into the chamber.

[0056] The first reactive gas A flows into one or more processing regions 250, and the inert gas flows into any processing region 250 into which the first reactive gas A does not flow. For example, if the first reactive gas flows into processing regions 250b to 250h, the inert gas will flow into processing region 250a. The inert gas may flow through the first reactive gas port 125 or the second gas port 135.

[0057] The inert gas in the processing area can be constant or variable. In some embodiments, the reactive gas co-flows with the inert gas. The inert gas will act as a carrier and diluent. Since the amount of reactive gas is small relative to the carrier gas, co-flowing can make it easier to balance the gas pressure between processing areas by reducing the pressure difference between adjacent areas.

[0058] Figure 6 A partial cross-sectional view of a substrate 60 with a feature 310 is shown. For illustrative purposes, these figures show a substrate with a single feature; however, one skilled in the art will appreciate that there may be multiple features. The shape or profile of feature 310 may be any suitable shape or profile, including but not limited to (a) vertical sidewalls and bottom surface, (b) tapered sidewalls, (c) undercuts, (d) concave profiles, (e) bends, (f) microgrooves, (g) curved bottom surfaces, and (h) cutouts. In this regard, the term "feature" refers to any intentional surface irregularity. Suitable embodiments of features include but are not limited to grooves and holes having a top, two sidewalls, and a bottom, and peaks having a top and two sidewalls. The feature may have any suitable aspect ratio (the ratio of feature depth to feature width). In certain embodiments, the aspect ratio is greater than or equal to about 5:1, 10:1, 15:1, 20:1, 25:1, 30:1, 35:1, or 40:1.

[0059] Substrate 60 has a substrate surface 320. At least one feature 310 forms an opening in substrate surface 320. Feature 310 extends a depth D from substrate surface 320 to bottom surface 312. Feature 310 has a first sidewall 314 and a second sidewall 316 that define a width W of feature 310. The open area formed by the sidewalls and bottom is also referred to as a gap.

[0060] Figure 7 A process 400 is shown as a flow chart of a bottom-up gap-fill process for an aluminum-containing film according to one or more embodiments of the present disclosure. Figure 7 and FIG. 8A to FIG. 8E, at 410 a substrate 60 is provided for processing. In this context, the term "providing" refers to placing a substrate in a location or environment for further processing. At 420, an Al-containing film 330 is deposited on the substrate surface 320 and the sidewalls 314, 316 and bottom 312 of the feature 310. The formation of the Al-containing film 330 includes sequentially exposing the substrate surface to an aluminum-containing precursor and a reactant. Deposition 420 may be repeated in a directly continuous step 422 as desired. Additionally, deposition 420 is repeated after using an etchant 440 until a gap-filling film is formed. In one or more embodiments, the depth and width of the feature are filled without voids or seams. According to one or more embodiments, the thickness of the aluminum-containing gap-filling film ranges from about to about

[0061] The film formed can be any suitable film. In certain embodiments, the film formed is a film comprising a x O y N z (I) an amorphous or crystalline aluminum-containing film of one or more species, wherein x, y and z are independently in the range of 0-3 depending on the nature of the atomic species, wherein the formula is an atomic composition rather than a stoichiometric representation. This formula includes: AlO, AlN, AlC, AlON, AlOC, AlCN, AlOCN, metallic Al and similar compositions. The film may be formed by any suitable process including, but not limited to, chemical vapor deposition (CVD), plasma assisted chemical vapor deposition (PECVD), atomic layer deposition (ALD) and plasma assisted atomic layer deposition (PEALD). The aluminum precursor may be any volatile aluminum source. Suitable aluminum precursors include, but are not limited to, AlR3, where R = any ligand that is bound to Al through C, N, O, H, S or a halide. For example, the aluminum precursor may include one or more of the following: an alkyl aluminum compound, an aluminum alkoxide-based compound, an aluminum amino-based compound, an aluminum halide, or a combination of the foregoing. In an embodiment, the aluminum precursor is trimethylaluminum (TMA). The precursor may be heated in a hot pot to increase the vapor pressure and delivered to the chamber using a carrier gas (e.g., ultra-high purity (UHP) Ar, He, H2, N2, etc.). The reactant may include an oxygen source, a nitrogen source, a carbon source, a hydrogen source, or a combination thereof. The reactant may be selected from the group consisting of: O2, O2 plasma, NO, NO plasma, N2O, N2O plasma, H2O, H2O plasma, D2O, O3, NH3, NH3 plasma, N2, N2 plasma, hydrazine, CO2, C1-C6 hydrocarbons, H2, H2 plasma, methanol, ethanol, isopropanol, or an Al-precursor.

[0062] In certain embodiments, the film 330 is conformally formed on at least one feature. As used herein, the term "conformal" or "conformally" refers to a layer that adheres to and uniformly covers an exposed surface and has a thickness that varies less than 5% relative to the average thickness of the film. For example, Thick films will have a thickness less than This thickness and variation includes the edges, corners, sides, and bottom of the recess. For example, in various embodiments of the disclosure, the conformal layer deposited by ALD will provide a substantially uniform thickness overlying the deposition area on the composite surface.

[0063] In certain embodiments, the film 330 is a continuous film. As used herein, the term "continuous" refers to a layer that covers the entire exposed surface without gaps or bare spots that reveal the material below the deposited layer. A continuous layer may have gaps or bare spots with a surface area less than about 1% of the total surface area of ​​the film.

[0064] The temperature during deposition 420 can be any suitable temperature, depending on, for example, the precursors used. In certain embodiments, the deposition temperature is in a range of about 50° C. to 550° C., or in a range of about 200° C. to about 500° C., or in a range of about 250° C. to about 450° C. Deposition 420 can occur with or without a plasma. The plasma can be a capacitively coupled plasma (CCP) or an inductively coupled plasma (ICP) or a microwave, and can be a direct plasma or a remote plasma. The processing chamber pressure during deposition 420 can be in a range of about 50 mTorr to 750 Torr, or in a range of about 100 mTorr to about 400 Torr, or in a range of about 1 Torr to about 100 Torr, or in a range of about 6.5 Torr to about 30 Torr.

[0065] Typically, a fluorine source alone is ineffective for etching aluminum-containing films. Therefore, the etching process disclosed herein includes the use of fluorination and an etchant. This process results in a non-conformal etch, where the etching rate at the top of a feature is greater than the etching rate at the bottom of the feature, such as a trench. Fluorination 430 treats an Al-containing film (AlC) with a fluoride source. x O y N z ; x, y and z are independently in the range of 0-3), the fluoride source is also referred to as a fluoriding agent. The reactivity of the fluoriding agent should be sufficient to convert AlC x O y N zConverted to AlF3. The fluorinating agent may include plasma. The plasma may be a directional plasma. The fluorinating agent may include WF6, NF3 plasma, NbF5, XeF2, F2, TiF4, hydrogen fluoride (HF), pyridine-HF, alkylamine-HF, metal halide, or a combination thereof. In an embodiment, the fluorinating agent includes: WF6, NF3 plasma, NbF5, XeF2, F2, TiF4, alkylamine-HF, metal halide, HF, or a combination thereof.

[0066] According to certain embodiments, by exposing the features to a plasma fluorination process, such as NF3 plasma, a higher degree of fluorination may be induced at the top of the feature than at the bottom. Since plasmas are inherently directional due to the presence of ions, without wishing to be bound by theory, when exposing structures having aspect ratios of 10:1 or greater to plasma, a higher degree of fluorination may be expected at the top of the feature than at the bottom. Likewise, preferentially fluorinating the top of the feature relative to the bottom of the feature (e.g., using a starved fluorination precursor) may promote non-conformal fluorination, resulting in an overall non-conformal etch using the etchant 440. If there is more AlF3, the etch rate at the top should be higher than the etch rate at the bottom, provided that the substrate is saturated with the etchant.

[0067] In certain embodiments, non-conformal etching (or non-conformal fluorination) is induced by a thermal fluorination process (without plasma), wherein the concentration of fluorinated molecules is controlled such that there are more fluorinated molecules at the top of the trench than at the bottom, which results in more fluorination at the top and a higher etch rate. In another aspect, the amount of fluorination can also be determined by the substrate temperature (the higher the temperature, the more fluorination). Fluorination of the Al-containing film 330 includes exposing the substrate surface to a fluorinating agent, which forms a fluorinated layer such as Figure 8B A fluorinated portion 340 is shown. The fluorinated portion includes AlF3.

[0068] The AlF3 is removed from the surface using an etchant 440. Saturation with the etchant helps remove remaining Al-F bonds. An etchant can be defined as any compound that can react with AlF3 to form a volatile AlF species that is removed from the surface. The etchant can be a ligand (L) that transfers a certain type of ligand (L) to the Al on the surface and forms a volatile L n AlF mSpecies molecules. Non-limiting embodiments include trimethylaluminum (TMA) and Sn(acac)2. Aluminum alkyls and certain Sn(II) compounds can also be used as etchants. In one or more embodiments, the etchant may include one or more of the following: R'3Al, wherein R' is an alkyl, an amine, or a combination thereof, such as trimethylaluminum (TMA); Sn(R")2, wherein R" is acetylacetone (acac), hexafluoroacetylacetone (hfac), or a combination thereof; Sn(R"')4, wherein R"' is an alkyl, an amine, an ether (e.g., methoxy (OMe), ethoxy (OE), isopropoxy (OiPr), tert-butoxy (Ot-Bu)), or a combination thereof; and Sn(R"")2, wherein R"" is a ligand based on cyclopentadiene (Cp). As Figure 8C As shown, the fluorinated portion is removed using an etchant and a non-conformally etched surface 345 is obtained. The non-conformally etched surface 345 has a V-shaped profile. The fluorine residue remaining on the surface after using the etchant may be a favorable poisoning effect, which means that during the subsequent Al deposition process, a non-conformal film may be formed, which is beneficial for bottom-up gap-filling.

[0069] Fig. 9 Schematic diagram of an etching process from a molecular perspective according to one embodiment. In this embodiment, NF3 plasma is used as a fluoride source and TMA is used as an aluminum fluoride etchant. The mixed alkyl aluminum fluoride species generated in this example are not volatile before about 250°C, so there is no etching below 250°C.

[0070] After using the etchant, the film can be optionally exposed to an oxidant to remove Al-F bonds not removed by the etchant. Suitable oxidizing chemistries include, but are not limited to, O2 plasma (RPS and direct), ozone, water, N2O, and any other oxidizing chemistry that converts any Al-F residues back to Al-O.

[0071] If the gap-fill film has not been completely formed, the steps of deposition 420 followed by fluorination 430 , use of an etchant 440 and optional oxidation 470 are repeated. Fig.8D A cross-sectional view of a gap partially filled by an Al-containing film 330 is provided. The process can be defined by (deposition) a→(etch) b, where "a" and "b" are independently the number of deposition cycles and etching cycles, respectively. In one or more embodiments, "a" is in the range of 0 to 1000 and "b" is in the range of 0 to 1000.

[0072] Gap-filling film 350 in Fig. 8E As shown in the figure, the gap is made of AlC x O y N zThe film is substantially or completely filled (x, y, and z are independently in the range of 0-3) with no voids or seams. After the gap-fill film is complete, the gap-filled substrate will exit the deposition / etch loop to one or more optional back-end processes 460.

[0073] The cross-sectional view of the gap filling film 350 after the back-end process 460 is shown in FIG. Figure 8F As shown, a portion of the Al-containing film 330 deposited on the substrate surface 320 is removed, and the Al-containing film 330 is left only inside the gap.

[0074] Fig.10 The thickness of an example of etching an Al2O3 film using NF3 plasma and TMA is shown. The relationship between temperature (°C). Etching with TMA / N2 and NF3 plasma at 200°C, 250°C and 290°C The pressure, NF3%, number of cycles and plasma power were 0.8T, 10%, 30 and 50W respectively. Fig.10 , a film believed to be AlF grew at 200°C. There was no growth or etching at 250°C, and there was etching at 290°C. These results show that the etching rate depends on the temperature.

[0075] The degree of fluorination depends on the aggressiveness of the NF3 plasma treatment. The degree of fluorination can be controlled by controlling the NF3%, plasma power, NF3 plasma pulse length, substrate temperature, and chamber pressure. The degree of surface fluorination can be minimized to achieve a more controlled etch process. If the degree of fluorination is not controlled, large pulse TMA can be used to convert all AlF species to AlF x (CH3) y species, and the TMA pulse may not saturate until a very large TMA pulse is given. Fig.11 As shown, at 2.5% NF3, increasing the NF3 plasma pulse increases the etching rate. Fig.12 It is shown that the TMA pulse can be saturated with 2.5% NF3 and at a 0.2 second TMA pulse.

[0076] Fig.13 The etch thickness is shown as a function of the number of deposition / etch cycles. The temperature, pressure, NF3%, TMA pulse and plasma power are 290℃, 0.8T, 2.5%, 0.2s and 50W respectively. Fig.13 As shown, the etching thickness increases linearly with the increase of the cycle number.

[0077] Fig.14A-B provides a scanning electron microscope (SEM) image of a 10:1 aspect ratio structure with trench features as a control example. Using TMA and H2O as precursors, a layer with a thickness of about 100 nm was deposited by ALD at a temperature of 290°C and a pressure of 0.8 Torr. The deposited film is substantially conformal with a side / top ratio of

[0078] Fig.15A -B provides a scanning electron microscope (SEM) image of a 10:1 aspect ratio structure with trench features after one hundred (deposition) a→(etch) b cycles (where a=1 and b=1). The deposition part was done with TMA and H2O, and the etching was done with NF3 plasma followed by TMA. The process was performed at 290°C and 0.8F. It is clear that the addition of the etching part provides non-conformal growth along the trench. The side / top ratio is The deposited film is better than the control ( Figures 14A-14B ) less conformal.

[0079] Therefore, one or more embodiments of the disclosure are directed to utilizing Figure 5 1. The processing method of the batch processing chamber shown. The substrate 60 is placed in a processing chamber having a plurality of regions 250a-h, each region separated from an adjacent region by a gas curtain 150. At least a portion of the substrate surface is exposed to a first process condition in a first processing region 250a of the processing chamber. The first process condition of certain embodiments includes an aluminum-containing precursor.

[0080] The substrate surface moves laterally through the gas curtain 150 to the second processing region 250b of the processing chamber. The substrate surface is exposed to a second process condition in the second processing region 250b. The second process condition of certain embodiments includes a x O y N z denoted as reactants of an aluminum-containing precursor to form a film, wherein x, y and z are independently in the range of 0-1.

[0081] The substrate surface moves laterally through the gas curtain 150 to the third region 250c of the processing chamber. The substrate surface can then be exposed to a third process condition in the third region 250c. The third process condition of certain embodiments includes a x O y N z The film reacts to form a fluorinating agent of AlF3.

[0082] The substrate surface moves laterally through the gas curtain 150 to a fourth region 250d of the processing chamber. The substrate surface can then be exposed to a fourth process condition in the fourth region 250d. The fourth process condition of certain embodiments includes an etchant that reacts with AlF3 to generate a removable volatile species.

[0083] In certain embodiments, the substrate is exposed to additional first and second process conditions to form a film having a predetermined film thickness. In certain embodiments, the substrate is exposed to additional third and fourth process conditions to repeatedly etch the substrate surface.

[0084] Optionally, the substrate surface moves laterally through the gas curtain 150 to a fifth region 250e of the processing chamber. The substrate surface can then be exposed to a fifth process condition in the fifth region 250e. The fifth process condition of certain embodiments includes an oxidant that reacts with Al-F bonds to form Al-O bonds.

[0085] According to one or more embodiments, the substrate is processed before and / or after the layer is formed. This processing can be performed in the same chamber, or in one or more separate processing chambers. In some embodiments, the substrate is moved from the first chamber to a separate second chamber for further processing. The substrate can be moved directly from the first chamber to the separate processing chamber, or the substrate can be moved from the first chamber to one or more transfer chambers and then to the separate processing chamber. Thus, the processing equipment may include multiple chambers connected to a transfer station. Such equipment may be referred to as a "cluster tool" or "cluster system" and the like.

[0086] Generally speaking, a cluster tool is a modular system that includes multiple chambers that perform various functions, including substrate centering and orientation, degassing, annealing, deposition, and / or etching. According to one or more embodiments, the cluster tool includes at least a first chamber and a central transfer chamber. The central transfer chamber can accommodate a robot that shuttles substrates between and among process chambers and load lock chambers. The transfer chamber is typically maintained under vacuum conditions and provides an intermediate stage for shuttling substrates from one chamber to another and / or to a load lock chamber at the front end of the cluster tool. Two well-known cluster tools that may be suitable for use in the present disclosure are and Both are available from Applied Materials, Inc., Santa Clara, California. However, the exact arrangement and combination of chambers may be varied to perform specific steps of the processes described herein. Other processing chambers that may be used include, but are not limited to: periodic layer deposition (CLD), atomic layer deposition (ALD), chemical vapor deposition (CVD), physical vapor deposition (PVD), etching, pre-cleaning, chemical cleaning, thermal treatments such as RTP, plasma nitridation, degassing, orientation, hydroxylation, and other substrate processes. By performing the process in a chamber on a cluster tool, atmospheric impurities may be avoided on the substrate surface without oxidation prior to deposition of subsequent films.

[0087] According to one or more embodiments, the substrate is continuously under vacuum or "load lock" conditions and is not exposed to ambient air when moved from one chamber to another. Therefore, the transfer chamber is under vacuum and is "evacuated" at vacuum pressure. An inert gas may be present in the processing chamber or the transfer chamber. In certain embodiments, the inert gas is used as a purge gas to remove some or all of the reactants. According to one or more embodiments, a purge gas is injected at the outlet of the deposition chamber to prevent reactants from moving from the deposition chamber to the transfer chamber and / or other processing chambers. Therefore, the inert gas flow forms a curtain at the outlet of the chamber.

[0088] Substrates may be processed in a single substrate deposition chamber where a single substrate is loaded, processed, and unloaded before another substrate is processed. Substrates may also be processed in a continuous manner similar to a conveyor belt system where multiple substrates are individually loaded into a first portion of the chamber, moved through the chamber, and then unloaded from a second portion of the chamber. The chamber and associated conveyor system may be shaped to form a straight path or a curved path. Alternatively, the processing chamber may be a turntable where multiple substrates are moved about a central axis and exposed to deposition, etching, annealing, cleaning, etc. processes throughout the turntable path.

[0089] During processing, the substrate may be heated or cooled. The heating or cooling may be achieved by any suitable means, including but not limited to changing the temperature of the substrate support and flowing a heated or cooled gas to the substrate surface. In some embodiments, the substrate support includes a heater / cooler that can be controlled to change the substrate temperature in a conductive manner. In one or more embodiments, the gas (either reactive or inert) is heated or cooled to locally change the substrate temperature. In some embodiments, the heater / cooler is located near the substrate surface in the chamber to change the substrate temperature in a convective manner.

[0090] The substrate may also be fixed or rotated during processing. The rotating substrate may be rotated continuously or discontinuously. For example, the substrate may be rotated throughout the process, or the substrate may be rotated a small amount between exposures to different reactive gases or purge gases. Rotating the substrate (continuously or stepwise) during processing can help produce a more uniform deposition or etching by minimizing the effects of local variability, such as gas flow geometry.

[0091] In an atomic layer deposition type chamber, a substrate can be exposed to a first and second precursor in processes that are separated in space or time. Temporal ALD is a conventional process where a first precursor flows into a chamber to react with a surface. The first precursor is purged from the chamber before flowing the second precursor. In spatial ALD, both the first and second precursors flow to the chamber simultaneously but are separated in space so that there is a region between the precursor flows that prevents mixing of the precursors. In spatial ALD, the substrate moves relative to a gas distribution plate, or the gas distribution plate moves relative to the substrate.

[0092] In embodiments where one or more portions of the method occur in one chamber, the process can be a spatial ALD process. Although one or more of the above chemicals may be incompatible (i.e., result in reactions at locations other than the substrate surface and / or deposition on the chamber), spatial separation ensures that the reagents are not exposed to each other in the gas phase. For example, temporal ALD involves cleaning the deposition chamber. However, in practice, it is sometimes impossible to remove all excess reagents from the chamber before flowing in additional reagents. Therefore, any residual reagents in the chamber may react. With spatial separation, there is no need to remove excess reagents, and cross contamination is limited. In addition, cleaning the chamber takes a lot of time, so the yield can be increased by eliminating the cleaning step.

[0093] Throughout the specification, references to "one embodiment," "certain embodiments," "one or more embodiments," or "an embodiment" mean that a particular feature, structure, material, or characteristic described in conjunction with that embodiment is included in at least one embodiment of the disclosure. Thus, phrases such as "in one or more embodiments," "in certain embodiments," "in an embodiment," or "in an embodiment" appearing in various places throughout the specification are not necessarily the same embodiment of the disclosure. Furthermore, in one or more embodiments, the particular features, structures, materials, or characteristics may be combined in any suitable manner.

[0094] Although the disclosure herein has been described with reference to specific embodiments, it should be understood that these embodiments are merely illustrations of the principles and applications of the disclosure. It will be apparent to those skilled in the art that various modifications and variations may be made to the methods and apparatus of the disclosure without departing from the spirit and scope of the disclosure. Therefore, it is intended that the disclosure be included within the scope of the appended claims and modifications and variations within the scope of their equivalents.

Claims

1. A processing method comprising the following steps: An aluminum-containing gap-fill film is deposited in a feature on a substrate surface in a bottom-up manner, the feature having a bottom surface, a top surface and sidewalls, the sidewalls extending a depth from the top surface to the bottom surface, the feature having a width defined by a first sidewall and a second sidewall, wherein the step of depositing the aluminum-containing gap-fill film in a bottom-up manner comprises: conformally depositing the aluminum-containing gap-fill film on the substrate surface and the first sidewall, the second sidewall and the bottom surface of the feature; and non-conformally etching the aluminum-containing gap-fill film deposited on the substrate surface by exposing the aluminum-containing gap-fill film to a fluorinating agent to form an aluminum fluoride species concentrated near the top surface of the feature, and exposing the aluminum-containing gap-fill film and the aluminum fluoride species to an etchant to etch a portion of the aluminum-containing gap-fill film near the top surface of the feature at a higher etching rate than the aluminum-containing gap-fill film at the bottom surface of the feature.

2. The process according to claim 1, wherein The step of non-conformally etching the aluminum-containing gap-fill film deposited on the substrate surface comprises: exposing the aluminum-containing gap-fill film to an aluminum-containing precursor, a reactant, the fluorinating agent, and an etchant in sequence; Alternatively, the aluminum-containing gap-fill film is exposed to a reactant, an aluminum-containing precursor, the fluorinating agent, and an etchant in sequence.

3. The processing method of claim 2, further comprising repeatedly forming the aluminum-containing gap-fill film by depositing the aluminum-containing gap-fill film and non-conformally etching the aluminum-containing gap-fill film deposited on the surface of the substrate until the aluminum-containing gap-fill film is formed so that the depth and the width of the feature are filled without voids.

4. The process of claim 1, wherein the thickness of the aluminum-containing gap-filling film is to in the range.

5. The method of claim 1, wherein the aluminum-containing gap-fill film comprises an AlC x O y N z Species of, wherein x, y and z are independently in the range of 0-3.

6. The method of claim 2, wherein the aluminum-containing precursor comprises an alkyl aluminum compound, an aluminum alkoxide-based compound, an aluminum amide-based compound, an aluminum halide, or a combination thereof.

7. The treatment method of claim 1, wherein the fluorinating agent comprises WF6, NF3 plasma, NbF5, XeF2, F2, TiF4, hydrogen fluoride (HF), pyridine-HF, alkylamine-HF, metal fluoride, or a combination thereof.

8. The processing method of claim 1, wherein the etchant comprises one or more of: R'3Al, wherein R' is an alkyl group, an amine, or a combination thereof; Sn(R")2, wherein R" is acetylacetone (acac), hexafluoroacetylacetone or a combination thereof; Sn(R'")4, wherein R' is alkyl, amine, ether or a combination thereof; and Sn(R"")2, where R"" is a cyclopentadiene (Cp) based ligand.

9. The process of claim 2, wherein the aluminum-containing precursor comprises trimethylaluminum (TMA), the fluorinating agent comprises NF3 plasma, and the etchant comprises trimethylaluminum (TMA).

10. The process of claim 1, wherein the aspect ratio of the feature is greater than or equal to 5:

1.

11. The process of claim 1 wherein the aluminum-containing gap-fill film is free of voids or seams.

12. A processing method comprising the following steps: placing a substrate surface in a processing chamber, the substrate surface having at least one feature thereon, the at least one feature creating a gap having a bottom surface, a top surface, and a plurality of sidewalls; exposing the substrate surface to an aluminum-containing precursor and a reactant to form a conformal aluminum-containing gap-fill film on the feature; exposing the conformal aluminum-containing gap-fill film on the feature to a fluorinating agent and an etchant to etch a portion of the aluminum-containing gap-fill film near the top surface of the feature at a higher etch rate than the aluminum-containing gap-fill film at the bottom surface of the feature by forming an aluminum fluoride species that is more concentrated near the top surface of the feature, and preferentially etching the portion of the conformal aluminum-containing gap-fill film at the top surface of the feature at a higher etch rate relative to the bottom surface of the feature; exposing the conformal aluminum-containing gap-fill film on the feature to an oxidant after the preferential etching step; and Repeating sequential exposure to the aluminum-containing precursor and the reactant followed by exposure to the fluorinating agent and the etchant and optionally an oxidizing agent fills the gaps of the feature in a bottom-up manner.

13. The process of claim 12, wherein the fluorinating agent comprises a plasma.

14. The process of claim 13 wherein the plasma is a directional plasma.

15. The process of claim 12, wherein the number of etching cycles is in the range of 0 to 1000.

16. The method of claim 12, wherein the substrate surface is sequentially exposed to the fluorinating agent and the etchant prior to each sequential exposure of the substrate surface to the aluminum-containing precursor and the reactant.

17. A processing method comprising the following steps: placing a substrate having a substrate surface having at least one feature having a top, a bottom, and a plurality of sides and an aspect ratio greater than or equal to 10:1 into a processing chamber comprising a plurality of sections, each section being separated from an adjacent section by a gas curtain; exposing at least a portion of the substrate surface to first process conditions in a first portion of the processing chamber, the first process conditions comprising an aluminum-containing precursor; moving the substrate surface laterally through the gas curtain to a second portion of the processing chamber; exposing the substrate surface to a second process condition in the second portion of the processing chamber, the second process condition comprising reactants with the aluminum-containing precursor to form a conformal aluminum-containing gap-fill film on the feature, the aluminum-containing gap-fill film comprising a AlC x O y N z Species, wherein x, y and z are independently in the range of 0-3; moving the substrate surface having the aluminum-containing gap-fill film on the feature laterally through a gas curtain to a third portion of the processing chamber; exposing the substrate surface having the aluminum-containing gap-fill film on the feature to a third process condition in the third portion of the processing chamber, the third process condition comprising a fluorinating agent to form an aluminum fluoride species that is more concentrated near the top of the feature than at the bottom of the feature; moving the substrate surface having the aluminum-containing gap-fill film on the feature laterally through a gas curtain to a fourth portion of the processing chamber; exposing the substrate surface having the aluminum-containing gap-fill film on the feature to fourth process conditions in the fourth portion of the processing chamber, the fourth process conditions comprising an etchant to preferentially etch at the top of the feature at a higher rate relative to the bottom of the feature by etching the aluminum-containing gap-fill film at the top of the feature at a higher rate than the aluminum-containing gap-fill film at the bottom of the feature; and optionally moving the substrate surface having the film on the feature laterally through a gas curtain to a fifth portion of the processing chamber; optionally exposing the substrate surface having the aluminum-containing gap-fill film on the feature to a fifth process condition in the fifth portion of the processing chamber, the fifth process condition comprising an oxidizing agent; and Repeating exposure to the first portion, the second portion, the third portion, the fourth portion, and optionally the fifth portion includes lateral movement of the substrate surface to conformally fill the feature with the aluminum-containing gap-fill film.

18. The method of claim 17, wherein the aluminum-containing precursor comprises trimethylaluminum (TMA), the fluorinating agent comprises NF3 plasma, and the etchant comprises trimethylaluminum (TMA).

19. The method of claim 17, wherein the aluminum-containing gap-fill film comprises AlO or AlN.

Images