Regulation treatments for ALD productivity

Abstract

Methods and apparatus for conditioning a process kit to increase the life of the process kit are described. A nitride film formed on a process kit is exposed to a conditioning process including nitrogen and hydrogen radicals to condition the nitride film to reduce particulate contamination from the process kit.

Description

[0001] This application is a divisional application of the invention patent application with the application date of February 6, 2021, application number 202180008851.9, and invention name “Processing for regulating ALD productivity”. Technical Field

[0002] Embodiments of the present disclosure generally relate to apparatus and methods for conditioning process chamber components. Specifically, embodiments of the present disclosure relate to methods and apparatus for nitride deposition with improved productivity. Background Art

[0003] Atomic layer deposition (ALD) process chambers used to deposit certain types of nitride films require frequent cleaning and maintenance. They have a low mean wafer between cleaning (MWBC) due to the nature of the materials deposited on the process kit (e.g., consumable parts used in the deposition chamber). The process kit includes, but is not limited to, elements of the deposition chamber that are removable parts that come into contact with the reactive chemicals during processing. For example, chamber showerheads, pumping liners, pump shields, etc.

[0004] During processing, ALD tantalum nitride (TaN) is deposited on the wafer as well as the process kit. The wafer temperature and the process kit temperature are different, with the wafer temperature being greater than the process kit. Due in part to this temperature difference, the TaN deposited on the process kit is different from the film deposited on the wafer. The TaN on the process kit is low density and has a high level of impurities. The TaN formed is powdery and causes particle problems. There is no known in-situ cleaning process that can clean ALD TaN from the process kit, so long equipment downtime is required for cleaning and maintenance.

[0005] Furthermore, plasma based processing is susceptible to increased particle contamination due to plasma induced stress accumulation on the chamber body. The particle lifetime of a process kit in a plasma process is about 20% of that of a process kit in a thermal processing chamber.

[0006] Therefore, there is a need for a method and apparatus to extend the mean wafers between cleans (MWBC) for nitride deposition processes. Summary of the invention

[0007] One or more embodiments of the present disclosure are directed to a deposition method that includes exposing a process kit of a process chamber having a nitride film thereon to a conditioning process including nitrogen and hydrogen radicals to form a conditioned nitride film. A nitride layer is deposited on a plurality of wafers in the process chamber.

[0008] Additional embodiments of the present disclosure are directed to a deposition method that includes processing a plurality of wafers in a process chamber to deposit tantalum nitride (TaN) on the wafers in the process chamber and depositing a nitride film on a process kit. The nitride film has a thickness of less than 9 g / cm 3 After processing the plurality of wafers, a conditioning process is used to condition the process kit. The conditioning process includes exposing the process kit to nitrogen and hydrogen radicals to increase the density of the nitride film to greater than 9 g / cm 3 , and produces a nitride film with compressive stress.

[0009] Further embodiments of the present disclosure relate to a non-transitory computer readable medium comprising instructions that, when executed by a controller of a processing chamber, cause the processing chamber to perform the following operations: exposing a substrate to a deposition process conditioning to deposit a nitride film; and exposing a process kit of the processing chamber to a conditioning process. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order that the manner in which the above-described features of the present disclosure may be understood in detail, a more particular description of the present disclosure, briefly summarized above, may be obtained by reference to the embodiments, some of which are illustrated in the accompanying drawings. It should be understood, however, that the drawings illustrate only typical embodiments of the present disclosure and, therefore, should not be considered as limiting the scope thereof, as the present disclosure may admit to other equally effective embodiments.

[0011] Figure 1 shows a schematic diagram of a processing chamber according to one or more embodiments of the present disclosure;

[0012] Figure 2 A flowchart of a processing method according to one or more embodiments of the present disclosure is depicted;

[0013] Figure 3A The following diagram shows the process before the adjustment process according to one or more embodiments of the present disclosure. Figure 1 an enlarged view of region 155; and

[0014] Figure 3B FIG. 1 shows a flow chart of ... according to one or more embodiments of the present disclosure. Figure 3A of the view. DETAILED DESCRIPTION

[0015] Before describing several exemplary embodiments of the present disclosure, it should be understood that the present disclosure is not limited to the details of construction or processing steps mentioned in the following description. The present disclosure is capable of other embodiments and can be practiced or carried out in various ways.

[0016] As used in this specification and the appended claims, the term "substrate" refers to a surface or portion of a surface upon which a process is applied. Those skilled in the art will also understand that reference to a substrate may also refer to only a portion of a substrate, unless the context clearly indicates otherwise. Furthermore, reference to a deposition on a substrate may refer to both a bare substrate and a substrate having one or more films or features deposited or formed thereon.

[0017] As used herein, "substrate" refers to any substrate or material surface formed on which film processing is performed during the manufacturing process. For example, the substrate surface on which the 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 material, such as metal, metal nitride, metal alloy and other conductive materials, depending on the application. The substrate includes but is not limited to a semiconductor wafer. The substrate may be exposed to a pretreatment process to polish, etch, reduce, oxidize, hydroxylate, anneal, UV cure, e-beam cure and / or bake the substrate surface. In addition to the film processing directly on the surface of the substrate itself, in the present disclosure, any film processing step disclosed may also be performed on a lower layer formed on the substrate, which will be disclosed in more detail below, and the term "substrate surface" is intended to include this lower layer as indicated by the context. Thus, for example, when a film / layer or a portion of a film / layer has been deposited onto a substrate surface, the exposed surface of the newly deposited film / layer becomes the substrate surface.

[0018] Embodiments of the present disclosure relate to methods of using conditioning treatments to enhance film properties of films formed on process kits. Certain embodiments of the present disclosure provide conditioning treatments on chamber showerheads, pumping liners, chamber insulators, or edge rings. Certain embodiments of the present disclosure advantageously provide methods of improving adhesion of films on process kits during deposition. One or more embodiments advantageously provide methods of reducing particle contamination from films formed on process kits. Certain embodiments advantageously provide methods for extending mean wafers between cleans (MWBC) for nitride deposition processes.

[0019] Certain embodiments of the present disclosure use mixed ammonia, hydrogen and argon plasma treatment to adjust the chamber body to densify the film deposited on the process kit by changing the film composition. In certain embodiments, the film deposited on the process kit is treated to increase the density of the film. In certain embodiments, the treatment process causes the film material to have a more neutral film stress. Certain embodiments improve the film properties of the material deposited on the process kit so that the adhesion to the process kit is improved over time. In certain embodiments, the adhesion is improved by reducing the particle formation in the chamber over time due to delamination, stress film fracture and / or showerhead peeling. In certain embodiments, the processing particle performance is improved to increase the particle life of the process kit. In certain embodiments, the particle performance is defined by a particle adder>32 nm. In certain embodiments, the particle performance is in the range of less than 5 particle adders (particles added to the wafer by processing) with a size greater than 32 nm. In certain embodiments, the particles are measured using a surface detection system such as one using light scattering. In certain embodiments, the particles are measured using a scanning electron microscope (SEM) to determine the particle size based on image analysis. In certain embodiments, particle maps and bin sizes are determined by optically measuring aberrations in the surface topography that indicate defects on the wafer surface. At smaller particle sizes, the particles measured may be wafer defects rather than particles added by processing, and the SEM may be used to inspect the top of the wafer before or after receiving a defect map from another technology. In certain embodiments, SEM images are acquired at one or more magnifications at multiple locations on the defect map and inspected for the presence of particles, correct bin size, particle morphology, and / or particle composition.

[0020] In certain embodiments, an ammonia (NH3) / hydrogen (H2) / argon (Ar) plasma treatment at various powers, process gas flow rates, and / or treatment times improves film density and / or grain properties. Nitration of an ALD nitride film (e.g., TaN) deposited on a process kit transforms a tensile, low-density, loose film into a higher density and more stress-neutral film. Unless otherwise noted, one skilled in the art will recognize that the use of terms like "tantalum nitride" or chemical formulas like "TaN" indicates the elemental composition of the material and does not imply any particular stoichiometric relationship of the composition. For example, unless otherwise noted, TaN refers to a film having tantalum and nitrogen atoms. In an example using a specific stoichiometric value, a low-density, tensile film comprising TaN is modified into a higher density, more stress-neutral Ta3N5.

[0021] Films deposited on process kits during deposition typically have high impurities and form powdery materials, which can cause particle issues, thereby reducing the MWBC for chambers in production. Certain embodiments of the present disclosure periodically modify the properties of films deposited on process kits during the life of the kit to help keep the film attached to the process kit, making the film denser and / or more stress neutral, making it less likely that defects that cause particle issues will occur.

[0022] According to certain embodiments of the present disclosure, Figure 1 The processing chamber 100 is shown, and Figure 2 Display processing method 200. Displayed on Figure 1 The processing chamber 100 in the embodiment includes a chamber body 110, a showerhead 120 (or other gas distribution plate), a confinement ring 125 (which may be omitted), a susceptor 130 (or other substrate support member), and a wafer 140. Figure 1 The process kit 150 in the process chamber 100 includes a susceptor 130 and a confinement ring 125. The process kit 150 having the nitride film 160 thereon is exposed to a conditioning process 210 to form a conditioned nitride film 165. The conditioning process of certain embodiments includes nitrogen radicals and hydrogen radicals. The method 200 further includes a deposition process 220 in which a nitride layer 170 is deposited on a plurality of wafers 140 in the process chamber 100. The plurality of wafers 140 of certain embodiments are processed individually. In certain embodiments, deposition occurs on more than one wafer at a time.

[0023] During the deposition process 220, in which the nitride layer 170 is formed on the surface of the wafer 140, some of the material is deposited on the process kit 150 (e.g., the showerhead 120 and / or the confinement rings 125) as the nitride film 160. The nitride film 160 formed on the process kit 150 has different properties than the nitride layer 170 formed on the wafer 140. Without being bound by any particular theory of operation, the difference in properties between the nitride film 160 and the nitride layer 170 is caused, among other things, by the temperature difference between the wafer 140 and the process kit 150.

[0024] Figure 3A illustrates an enlarged view of region 155 prior to conditioning process 210, and Figure 3B The diagram shows the adjustment process 210. Figure 3A View of. Figure 3A In some embodiments, the conditioning process 210 increases the density of the nitride film 160 to form a nitride film 160 having a relatively low density and being subjected to tensile stress. Figure 3B 1. The conditioned nitride film 165 is shown in FIG. The conditioned nitride film 165 may also be referred to as a densified nitride film.

[0025] In some embodiments, the nitride film 160 is formed on the process kit 150 during a nitride deposition process that forms a nitride layer on one or more wafers. In some embodiments, the nitride layer is deposited by one or more of chemical vapor deposition (CVD) or atomic layer deposition. In some embodiments, the nitride layer and the nitride film are deposited by atomic layer deposition. In some embodiments, the nitride layer is deposited on multiple wafers simultaneously or sequentially.

[0026] In certain embodiments, the nitride film 160 deposited on the process kit 150 comprises one or more of: tantalum nitride (TaN), titanium nitride (TiN), manganese nitride (MnN), tungsten nitride (WN), ruthenium tantalum nitride (RuTaN), or niobium nitride (NbN). In certain embodiments, the nitride film 160 deposited on the process kit 150 comprises or consists essentially of tantalum nitride (TaN). As used in this manner, the term "consisting essentially of" means that the composition of the film is greater than or equal to 90%, 92.5%, 95%, 98%, 99%, or 99% of the sum of the elements on an atomic basis. In certain embodiments, the nitride film 160 deposited on the process kit 150 comprises or consists essentially of titanium nitride. In certain embodiments, the nitride film 160 deposited on the process kit 150 comprises or consists essentially of niobium nitride.

[0027] In some embodiments, the nitride film 160 comprises tantalum nitride, which has a relatively low density under tensile stress. As used herein, the term "relatively low density" means that the density of the tantalum nitride film is less than or equal to 8 g / cm2 before the conditioning process. 3 , 7.5 g / cm 3 , 7 g / cm 3 、6.5 g / cm 3 , 6 g / cm 3 , 5.5 g / cm 3 or 5 g / cm 3 .

[0028] In certain embodiments, the tantalum nitride film formed on the process kit has a relative humidity of 5 g / cm2 before the conditioning process. 3 Up to 6.5 g / cm 3In some embodiments, the nitride film 160 formed on the process kit comprises tantalum nitride having tensile stress prior to conditioning treatment. In some embodiments, ellipsometry is used to measure the differential stress (measured by XRF) in a deposited film having a known thickness. Prior to treatment, the ALD TaN film is very tensile, with tensile stress ranging from 100 MPa to 1500 MPa. In some embodiments, after treatment, the ALD Ta3N5 film is more stress neutral / compressive. In some embodiments, the stress of the treated film is in the range of 0 to -500 MPa. In some embodiments, ellipsometry is used to measure the radius of curvature of the wafer before and after film deposition. Curvature delta is used to calculate film stress with a known film thickness.

[0029] Conditioning process 210 changes nitride film 160 into conditioned nitride film 165. Conditioned nitride film 165 of certain embodiments has a density greater than or equal to 9 g / cm 3 , 9.5 g / cm 3 or 10 g / cm 3 In some embodiments, the conditioned nitride film 165 comprises tantalum nitride, which has a density of 9 g / cm 3 Up to 10.5 g / cm 3 or 9.5 g / cm 3 Up to 10 g / cm 3 density in the range of .

[0030] In certain embodiments, the conditioned nitride film has a compressive stress. In certain embodiments, the compressive stress is in the range of about 0 to about -500 MPa as measured by ellipsometer.

[0031] The conditioning treatment of certain embodiments comprises nitrogen radicals and hydrogen radicals. In certain embodiments, the nitrogen radicals and hydrogen radicals are formed by passing the conditioning gas through a hot wire. In certain embodiments, the nitrogen radicals and hydrogen radicals are formed in a plasma generated from the conditioning gas. In certain embodiments, the plasma is a direct plasma. In certain embodiments, the plasma is a remote plasma.

[0032] The regulating gas of certain embodiments comprises one or more of the following: ammonia (NH3), hydrazine (N2H4), nitrogen (N2), hydrogen (H2), or argon (Ar). The regulating gas of certain embodiments comprises one or more of the following: ammonia (NH3), hydrazine (N2H4), nitrogen (N2), hydrogen (H2), or argon (Ar), with the proviso that each of nitrogen (N2), hydrogen (H2), or argon (Ar) is used with at least one additional gas species to provide nitrogen and hydrogen radicals. In certain embodiments, the regulating gas comprises an ammonia hydrogen compound (azane). In certain embodiments, the regulating gas comprises one or more of the following: diazane (hydrazine), triazane (N3H5), diazene (N2H2), or triazene (N3H3). In certain embodiments, the regulating gas comprises at least one species having both nitrogen atoms and hydrogen atoms. In certain embodiments, the regulating gas comprises or consists essentially of ammonia (NH3). As used in this manner, the term "consisting essentially of" means that on a molecular basis, the reactive species in the modulating gas is greater than or equal to 95%, 98%, 99%, or 99.5%, or the sum of said species, not counting inert or diluent species. In certain embodiments, the modulating gas comprises or consists essentially of hydrazine (N2H4). In certain embodiments, the modulating gas comprises or consists essentially of ammonia and hydrogen (H2). In certain embodiments, the modulating gas comprises or consists essentially of hydrogen (H2) and nitrogen (N2).

[0033] In certain embodiments, the regulating gas comprises ammonia (NH3), hydrogen (H2), and argon (Ar). In certain embodiments, the regulating gas consists essentially of ammonia (NH3), hydrogen (H2), and argon (Ar). The ratio of ammonia:hydrogen:argon (NH3:H2:Ar) of certain embodiments is in the range of 0.9-1.1 NH3:0.9-1.1 H2:0.9-1.1 Ar. In certain embodiments, the ratio of ammonia:hydrogen:argon (NH3:H2:Ar) is about 1:1:1. In certain embodiments, the ratio of ammonia:hydrogen:argon (NH3:H2:Ar) is in the range of 1-20 NH3:1-20 H2:1 Ar, or in the range of 1-10:1-10:1, or in the range of 10:10:0.1-10 Ar. In certain embodiments, the amounts of ammonia (NH 3 ) and hydrogen (H 2 ) are within ±10% relative to each other, and argon (Ar) is a diluent in any suitable amount to provide sufficient reactive species in the processing chamber.

[0034] In certain embodiments, the conditioning gas comprises a plasma having a frequency in the range of about 2 MHz to 100 MHz, 13.56 MHz to 60 MHz, 13.56 MHz to 40 MHz. In certain embodiments, the conditioning gas comprises a plasma having a pressure in the range of about 0.5 torr to about 25 torr, or in the range of about 1 torr to 15 torr, or in the range of about 1.5 torr to about 10 torr. In certain embodiments, the conditioning gas comprises a plasma, and the conditioning process is performed for less than or equal to five minutes.

[0035] Reference Figure 2 , after the conditioning process 210, a nitride layer is deposited 220 on one or more wafers (substrates). The number of wafers deposited before re-performing the conditioning process kit 150 depends on, for example, the conditioning process parameters used, the deposition parameters, and the nitride layer composition. Certain embodiments of the present invention provide a process kit 150 with a lifetime of at least 5 times (5x) compared to a process kit that does not perform the conditioning process 210. In certain embodiments, the lifetime of a process kit is defined as the number of wafers that can be processed between cleaning or preventive maintenance. For any given process, a typical reference lifetime is in the range of <1K to 10K.

[0036] Certain embodiments of the method begin with a seasoning process 205 to condition the process kit 150. Certain embodiments of the conditioning process 205 use a deposition process 220 and then a conditioning process 210 to prepare the process kit 150 for use. In certain embodiments, the process kit 150 undergoes the conditioning process 205 before being installed in the deposition chamber. In certain embodiments, the conditioning process 205 includes a form of deposition process and a subsequent form of conditioning process. In certain embodiments, the conditioning process includes a form of deposition process, and the method 200 moves to the conditioning process 210 as the next procedure to condition and complete the conditioning process. In certain embodiments in which the conditioning process includes a form of conditioning process, after the conditioning process 205, the method follows the optional path 222 to the deposition process 220.

[0037] Reference Figure 1 , additional embodiments of the present disclosure are directed to a processing chamber 100 for performing the methods described herein. Figure 1A chamber 100 that can be used to process a substrate according to one or more embodiments of the present disclosure is illustrated. The processing chamber 100 includes at least one controller 190 that is configured to control various components of the chamber 100. In certain embodiments, there is more than one processor connected to the processing chamber 100, with a main control processor coupled to each of the separate processors to control the chamber 100. The controller 190 can be one of any form of general purpose computer processor, microcontroller, microprocessor, etc. that can be used in an industrial setting for controlling various chambers and sub-processors.

[0038] In some embodiments, the controller 190 has a processor 192 (also referred to as a CPU), a memory 194 coupled to the processor 192, an input / output device 196 coupled to the processor 192, and a support circuit 198 to communicate between different electronic components. In some embodiments, the memory 194 includes one or more of a temporary memory (e.g., a random access memory) or a non-temporary memory (e.g., a storage device).

[0039] The processor's memory 194, or computer readable medium, may be one or more of the following: readily available memory such as random access memory (RAM), read-only memory (ROM), floppy disk, hard disk, or any form of digital storage device, whether local or remote. The memory 194 may store instruction sets that are operable by the processor 192 to control parameters and components of the system. Support circuits 198 are coupled to the processor 192 for supporting the processor in a conventional manner. The circuits may include, for example, caches, power supplies, clock circuits, input / output circuitry, subsystems, and the like.

[0040] The process may typically be stored in a memory as a software routine that, when executed by a processor, causes the processing chamber to perform the process of the present disclosure. The software routine may also be stored and / or executed by a second processor (not shown) that is located remotely from the hardware controlled by the processor. Some or all of the methods of the present disclosure may also be performed in hardware. Thus, the process may be implemented in software and executed using a computer system, implemented in hardware, such as as an application specific integrated circuit or other type of hardware, or implemented as a combination of software and hardware. When executed by a processor, the software routine converts a general purpose computer into a special purpose computer (controller) that controls the chamber operation so that the process can be performed.

[0041] In some embodiments, the controller 190 has one or more configurations to perform individual processes or sub-processes to perform the method. In some embodiments, the controller 190 is connected to and configured to operate intermediate components to perform the functions of the method. For example, the controller 190 of some embodiments is connected to and configured to control one or more of a gas valve, an actuator, a motor, a slit valve, a vacuum control, etc.

[0042] The controller 190 of certain embodiments has one or more configurations selected from: a configuration for exposing a substrate to a deposition process conditioning to deposit a nitride film; a configuration for exposing a process kit of a processing chamber to a conditioning process. A non-transitory computer readable medium includes instructions that, when executed by a controller of a processing chamber, cause the processing chamber to perform the following operations: exposing a substrate to a deposition process conditioning to deposit a nitride film; and exposing a process kit of a processing chamber to a conditioning process.

[0043] References to "one embodiment", "certain embodiments", "one or more embodiments" or "an embodiment" throughout this specification refer to specific features, structures, materials or characteristics described in association with the embodiment being included in at least one embodiment of the present disclosure. Therefore, phrases such as "in one or more embodiments", "in certain embodiments", "in one embodiment" or "in an embodiment" appearing throughout this specification do not necessarily refer to the same embodiment of the present disclosure. Furthermore, specific features, structures, materials or characteristics may be combined in any suitable manner in one or more embodiments.

[0044] Although the present disclosure has been described with reference to specific embodiments, those skilled in the art will appreciate that the described 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 changes may be made to the methods and apparatus of the present disclosure without departing from the spirit and scope of the present disclosure. Therefore, the present disclosure may include modifications and changes that fall within the scope of the appended claims and their equivalents.

Claims

1. A deposition method comprising the following steps: exposing a process kit of a processing chamber having a nitride film thereon to a conditioning process, the conditioning process comprising the steps of: exposing the process kit to a conditioning gas to form a conditioned nitride film, the conditioning gas comprising hydrogen and nitrogen; and depositing a nitride layer on a plurality of wafers in the processing chamber, wherein the nitride film on the process kit is formed during deposition of the nitride layer on the plurality of wafers within the process chamber, and wherein the conditioning process increases the density of the nitride film on the process kit, and the nitride film has a density less than or equal to 8 g / cm 3 The adjusted nitride film has a density greater than or equal to 10 g / cm 3 density.

2. The method of claim 1, wherein the nitride film comprises one or more of: tantalum nitride (TaN), titanium nitride (TiN), ruthenium tantalum nitride (RuTaN), manganese nitride (MnN), tungsten nitride (WN), or niobium nitride (NbN).

3. The method of claim 1, wherein the conditioning process comprises forming a plasma from the conditioning gas.

4. The method of claim 3, wherein the plasma has a frequency in the range of 13.56 to 40 MHz. The method of claim 3 , wherein the plasma has a pressure in the range of 1.5 to 10 torr. The method of claim 3 , wherein the conditioning process is performed for less than or equal to five minutes.

7. The method of claim 1, wherein the nitride layer on the plurality of wafers is deposited by atomic layer deposition.

8. The method of claim 1, wherein the plurality of wafers is in the range of 5 to 50 prior to additional exposure to the conditioning process.

9. The method of claim 1, wherein the life of the process kit is increased at least 5 times relative to a process without the conditioning process.

10. The method of claim 1, wherein the process kit comprises one or more of a showerhead, a pumping pad, or an edge ring.

11. A non-transitory computer readable medium comprising instructions which, when executed by a controller of a processing chamber, cause the processing chamber to perform the method of claim 1.

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