Catalytic Deposition of Metal Films

Abstract

Methods for depositing high-purity metal films are discussed. Some embodiments utilize a thermal ALD process comprising alkyl halides and metal precursors. Some embodiments selectively deposit high-purity metal films on metal surfaces rather than dielectric surfaces. Some embodiments selectively deposit high-purity metal films on dielectric surfaces rather than metal surfaces. Some embodiments deposit metal films having a metal atom content greater than 99% on an atomic basis.

Description

Technical Field

[0001] Embodiments of the present disclosure are generally related to methods for depositing metal films. Some embodiments of the present disclosure are related to methods for depositing metal films. Some embodiments of the present disclosure are related to selective deposition of metal films. Some embodiments of the present disclosure control the location and / or rate of deposition via the use of plasma and / or thermal exposure conditions. Background Art

[0002] The semiconductor industry continues to pursue continued device miniaturization driven by the need for mobile and high-performance systems in emerging industries such as autonomous vehicles, virtual reality, and future mobile devices. To accomplish this task, new high-performance materials are needed to circumvent the inherent engineering, chemical, and physical problems encountered when rapidly shrinking features in microelectronic devices.

[0003] Ruthenium is a newly proposed material for integration due to its high melting point (ability to withstand high current density), exceptional density, and ability to conduct electrical current. Ruthenium and ruthenium-containing films have attractive material and conductive properties. Ruthenium films have been proposed for applications ranging from the front-end to the back-end parts of semiconductor and microelectronic devices.

[0004] Ruthenium thin films are ideally deposited using thin film deposition techniques such as Chemical Vapor Deposition (CVD) and Atomic Layer Deposition (ALD) due to their inherent ability to deposit materials in a high throughput and precise manner.

[0005] The freshly deposited ruthenium film is often different from the bulk ruthenium material. There are special challenges when depositing ruthenium films with high purity (>99 atomic % Ru), especially as gap fill materials. Previous solutions have used oxygen reactants to produce films that have greater roughness than the bulk material. Similarly, hydrogen reactants produce higher impurities that require subsequent annealing steps to remove. Finally, plasma deposition processes cannot deposit gap fill materials without creating seams and potentially damaging the underlying substrate.

[0006] Therefore, there is a need for methods and materials for depositing high purity conformal ruthenium films as gap fills. There is also a need for methods and materials for depositing ruthenium films as gap fills without seams or voids.

[0007] In addition, as the design of semiconductor devices evolves, precision material manufacturing in the semiconductor industry has entered the era of atomic size. At the atomic scale, only tens of atoms are critical and there is a small margin of error. This unprecedented challenge requires new material processing technologies with atomic-level precision. However, increasing the complexity of the process flow required in atomic-scale device manufacturing can significantly reduce yield and increase manufacturing costs.

[0008] Selective deposition techniques offer the potential for chemical selectivity with atomic layer precision in semiconductor film patterning. Selective deposition also offers the potential to simplify process flow by eliminating photolithography or other processes.

[0009] Selective deposition of materials can be achieved in a variety of ways. For example, some processes may have inherent selectivity for a surface based on its surface chemistry. These processes are quite rare and usually require surfaces with significantly different surface energies, such as metals and dielectrics.

[0010] Therefore, there is a need for methods to selectively deposit metal films on metal surfaces in preference to dielectric surfaces, or vice versa.

[0011] Additionally, current devices use tungsten films for memory and logic applications. Deposition of tungsten films is frequently performed at relatively high temperatures, which may be limited by the thermal budget of the component being formed. Tungsten films are often deposited using fluorine-containing compounds. Fluorine is generally not desirable in a deposition process due to possible reactions and adverse effects. To prevent the fluorine from reacting with underlying layers, a relatively thick barrier layer is used. Barrier layer deposition reduces thermal budget and throughput.

[0012] Therefore, there is a need in the art for conductive materials that do not use fluorine and / or can be deposited at low temperatures. Summary of the invention

[0013] One or more embodiments of the present disclosure relate to a metal deposition method. A substrate is sequentially exposed to a metal precursor and an alkyl halide to form a metal film. The substrate is maintained at a deposition temperature. The metal precursor has a decomposition temperature higher than the deposition temperature. The alkyl halide comprises carbon and a halogen. The halogen comprises bromine or iodine.

[0014] Additional embodiments of the present disclosure relate to a method for selectively depositing a first metal film on a first dielectric surface. The method includes providing a substrate having a first dielectric surface and a second metal surface. The substrate is exposed to a blocking compound to block the second metal surface. The blocking compound has the general formula R'≡R", where R' and R" are alkyl or other carbon-containing groups. The substrate is sequentially exposed to a first metal precursor and an alkyl halide while maintaining the substrate at a deposition temperature. The alkyl halide comprises carbon and halogen atoms. The halogen atoms comprise bromine or iodine, and the deposition temperature is between the decomposition temperatures of the alkyl halide and the first metal precursor.

[0015] A further embodiment of the present disclosure relates to a method for selectively depositing a first metal film on a second metal surface. The method includes providing a substrate having a first dielectric surface and a second metal surface. The substrate is sequentially exposed to a first metal precursor and an alkyl halide while maintaining the substrate at a deposition temperature. The alkyl halide comprises carbon and halogen atoms. The halogen atoms comprise bromine or iodine. Both the metal precursor and the alkyl halide have a decomposition temperature above the deposition temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] 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 accompanying drawings only illustrate common embodiments of the present disclosure and are not to be considered as limiting the scope of the present disclosure, as the present disclosure may admit to other equally effective embodiments.

[0017] Figure 1 A schematic diagram of a processing platform according to one or more embodiments of the present disclosure is shown;

[0018] Figure 2 shows a cross-sectional view of a batch processing chamber according to one or more embodiments of the present disclosure;

[0019] Figure 3 shows a partial perspective view of a batch processing chamber according to one or more embodiments of the present disclosure;

[0020] Figure 4 shows a schematic diagram of a batch processing chamber according to one or more embodiments of the present disclosure;

[0021] Figure 5 A schematic diagram illustrating a portion of a wedge-shaped gas distribution assembly for use in a batch processing chamber according to one or more embodiments of the present disclosure;

[0022] Figure 6shows a schematic diagram of a batch processing chamber according to one or more embodiments of the present disclosure;

[0023] Figure 7 An exemplary process sequence for forming a metal layer using a two-pulse cyclic deposition technique according to one or more embodiments of the present disclosure is illustrated.

[0024] Figure 8 An exemplary process sequence for forming a ruthenium layer according to one or more embodiments of the present disclosure is illustrated.

[0025] Fig. 9 shows a cross-sectional view of an exemplary substrate according to one or more embodiments of the present disclosure; and

[0026] FIG. 10A to FIG. 10D An exemplary substrate during processing according to one or more embodiments of the present disclosure is illustrated.

[0027] In the accompanying drawings, similar components and / or features may have the same reference numeral. In addition, components of the same type may be distinguished by following the reference numeral with a dashed line and a second reference numeral that distinguishes between the similar components. If only the first reference numeral is used in this specification, the description applies to any of the similar components having the same first reference numeral, regardless of the second reference numeral. DETAILED DESCRIPTION

[0028] 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 routines set forth in the following description. The present disclosure is capable of other embodiments and of being practiced or carried out in various ways.

[0029] As used herein, "substrate," "substrate surface," or similar terms refer to any substrate or any material surface formed on a substrate on which processing is performed. For example, depending on the application, substrate surfaces on which processing may be performed include, but are not limited to: a material such as silicon, silicon oxide, strained silicon, silicon on insulator (SOI), carbon-doped silicon oxide, silicon nitride, doped silicon, germanium, gallium arsenide, glass, sapphire; and any other material such as metals, metal nitrides, metal alloys, and other conductive materials. Substrates include, but are not limited to, semiconductor wafers. The substrate may be exposed to a pretreatment process to polish, etch, reduce, oxidize, hydroxylate (or otherwise create or graft target chemical moieties to impart chemical functionality), anneal, and / or bake the substrate surface. In addition to processing directly on the surface of the substrate itself, in the present disclosure, as disclosed in more detail below, any of the disclosed film processing steps may also be performed on an underlying layer formed on the substrate, and the term "substrate surface" is intended to include such underlying layers as indicated by the context. Thus, for example, where a film / layer or 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. What material a given substrate surface contains will depend on what material is to be deposited, and the specific chemistry used.

[0030] As used herein, "atomic layer deposition" or "cyclic deposition" refers to the sequential exposure of two or more reactive compounds to deposit a layer of material on a substrate surface. As used in this specification and the appended claims, the terms "reactive compound", "reactive gas", "reactive substance", "precursor", "processing gas" and similar terms are used interchangeably to mean a substance having a species capable of reacting with a substrate surface or a material on a substrate surface in a surface reaction (e.g., chemical adsorption, oxidation, reduction). The substrate, or a portion of the substrate, is separately exposed to two or more reactive compounds, which are introduced into a reaction zone of a processing chamber. In a time-domain ALD process, exposure to each reactive compound is separated by a time delay to allow each compound to adhere to and / or react on the substrate surface and then purge the compound from the processing chamber. It is considered that the reactive compounds are exposed to the substrate sequentially. In a spatial ALD process, different portions of the substrate surface, or materials on the substrate surface, are simultaneously exposed to two or more reactive compounds, so that any given point on the substrate is not substantially simultaneously exposed to more than one reactive compound. As used in this specification and the appended claims, as will be understood by those skilled in the art, the term "substantially" used in this regard means that there is a possibility that a small portion of the substrate may be exposed to multiple reactive gases simultaneously due to diffusion, and that such simultaneous exposure is not intended.

[0031] In one aspect of a time-domain ALD process, a first reactive gas (i.e., a first precursor or compound A) is pulsed into a reaction zone, followed by a first time delay. Next, a second precursor or compound B is pulsed into the reaction zone, followed by a second delay. During each time delay, a purge gas (such as argon) is introduced into the processing chamber to purge the reaction zone or otherwise remove any residual reactive compounds or reaction byproducts from the reaction zone. Alternatively, the purge gas may flow continuously throughout the deposition process, such that only the purge gas flows during the time delay between pulses of the reactive compounds. The reactive compounds are pulsed alternately until a desired film or film thickness is formed on the substrate surface. In either case, the ALD process of pulsing compound A, purge gas, compound B, and purge gas is a cycle. The cycle may start with either compound A or compound B, and continue the corresponding order of cycles until a film having a predetermined thickness is obtained.

[0032] In one embodiment of a spatial ALD process, a first reactive gas and a second reactive gas (e.g., a metal precursor gas) are delivered to the reaction zone simultaneously, but separated by an inert gas curtain and / or a vacuum curtain. The substrate moves relative to the gas delivery apparatus so that any given point on the substrate is exposed to the first reactive gas and the second reactive gas.

[0033] 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 gas species that can react with a substrate surface.

[0034] Some embodiments of the present disclosure relate to processes using a reaction chamber with multiple gas ports that can be used to introduce different chemicals or plasma gases. Spatially, these gas ports (also called channels) are separated by inert purge gas and / or vacuum pumping holes to create a gas curtain that minimizes or eliminates mixing of gases from different gas ports to avoid unwanted gas phase reactions. Wafers moving through these different spatially separated ports are continuously and repeatedly exposed to different chemicals or plasma environments, so that layer-by-layer film growth or surface etching processes in spatial ALD mode occur. In some embodiments, the processing chamber has a modular architecture on the gas distribution component, and each modular component has independent parameter control (e.g., RF or gas flow) to provide flexibility in controlling, for example, gas flow and / or RF exposure.

[0035] Some embodiments of the present disclosure provide methods for depositing high-purity metal films. The methods of various embodiments use atomic layer deposition (ALD) to provide pure or nearly pure metal films. Although exemplary embodiments of the present disclosure refer to depositing ruthenium, it is contemplated that the principles of the present disclosure can be used to deposit high-purity metal films regardless of the metal.

[0036] Some embodiments of the present disclosure provide methods for selectively depositing a metal film on a metal surface over a dielectric surface. Some embodiments of the present disclosure provide methods for selectively depositing a metal film on a dielectric surface over a metal surface. As used in this specification and the appended claims, the term "selectively depositing a film on one surface over another surface" and similar expressions mean that a first amount of film is deposited on a first surface and a second amount of film is deposited on a second surface, wherein the second amount of film is less than the first amount of film, or no film is deposited on the second surface.

[0037] The term "preferentially" as used in this context does not imply a physical orientation of one surface on top of another surface, but rather a relationship of the thermodynamic or kinetic properties of the chemical reaction of one surface relative to the other surface. For example, selectively depositing a metal film onto a metal surface in preference to a dielectric surface means that the metal film is deposited on the metal surface, and little or no metal film is deposited on the dielectric surface; or that forming a metal film on the metal surface is thermodynamically or kinetically favorable relative to forming a metal film on a dielectric surface.

[0038] The selectivity of a deposition process is roughly expressed as a multiple of the growth rate. For example, if the growth (or deposition) on one surface is 25 times faster than on a different surface, the process would be described as having a selectivity of 25: 1. In this regard, a higher ratio indicates a more selective process.

[0039] Some embodiments of the present disclosure advantageously provide methods for depositing metal films having high purity. Thus, these high purity films exhibit properties similar to the host metal material with which they are associated. For example, some embodiments of the present disclosure provide ruthenium films that are smoother and have lower resistance than ruthenium films deposited by conventional oxygen or hydrogen reactant processes. Some embodiments of the present disclosure advantageously provide metal films that conformally fill gaps without seams.

[0040] Some embodiments of the present disclosure advantageously provide selective deposition of metal films with high purity on metal surfaces in preference to dielectric surfaces. For example, selective deposition of metal (e.g., ruthenium) on copper in preference to dielectric advantageously provides a copper capping layer without additional etching or photolithography steps. In addition, selective deposition can also enable bottom-up gap filling for trenches with metal contacts at the bottom and dielectric sidewalls.

[0041] Some embodiments of the present disclosure advantageously provide selective deposition of metal films with high purity on dielectric surfaces in preference to metal surfaces. For example, selective deposition of metal over dielectrics advantageously provides a metal layer on a barrier or other dielectric in back-end applications.

[0042] Some embodiments of the present disclosure utilize a spatial ALD process that is performed on a processing platform as disclosed herein. Figure 1 A processing platform 100 is shown in accordance with one or more embodiments of the present disclosure. Figure 1 The illustrated embodiment is merely representative of one possible configuration and should not be considered to limit the scope of the present disclosure.For example, in some embodiments, the processing platform 100 has a different number of processing chambers, buffer chambers, and robotic configurations.

[0043] The processing platform 100 includes a central transfer station 110 having a plurality of sides 111, 112, 113, 114, 115, 116. The central transfer station 110 is shown having a first side 111, a second side 112, a third side 113, a fourth side 114, a fifth side 115, and a sixth side 116. Although six sides are shown, those skilled in the art will appreciate that the central transfer station 110 may have any suitable number of sides, for example, depending on the overall configuration of the processing platform 100.

[0044] The transfer station 110 has a robot 117 positioned therein. The robot 117 can be any suitable robot capable of moving a wafer during processing. In some embodiments, the robot 117 has a first arm 118 and a second arm 119. The first arm 118 and the second arm 119 can move independently of the other arms. The first arm 118 and the second arm 119 can move in the xy plane and / or along the z axis. In some embodiments, the robot 117 includes a third arm or a fourth arm (not shown). Each arm can move independently of the other arms.

[0045] The first batch processing chamber 120 can be connected to the first side 111 of the central transfer station 110. For batch time, the first batch processing chamber 120 can be configured to process x wafers at a time. In some embodiments, the first batch processing chamber 120 can be configured to process a range of about four (x=4) to about twelve (x=12) wafers simultaneously. In some embodiments, the first batch processing chamber 120 is configured to process six (x=6) wafers simultaneously. As will be appreciated by those skilled in the art, although the first batch processing chamber 120 can process multiple wafers between loading / unloading individual wafers, each wafer may be experiencing different processing conditions at any given time. For example, a spatial atomic layer deposition chamber, such as Figure 2 Until Figure 6 As shown, the wafer is exposed to different processing conditions in different processing zones so that the process is completed as the wafer moves through each zone.

[0046] Figure 2 A cross section of a processing chamber 200 is shown, which includes a gas distribution assembly 220, also known as an injector or injector assembly, and a pedestal assembly 240. The gas distribution assembly 220 is any type of gas delivery assembly used in a processing chamber. The gas distribution assembly 220 includes a front surface 221 facing the pedestal assembly 240. The front surface 221 can have any number or variety of openings for delivering a gas flow toward the pedestal assembly 240. The gas distribution assembly 220 also includes an outer periphery 224, which in the embodiment shown is substantially circular.

[0047] The particular type of gas distribution assembly 220 used may vary depending on the specific process used. Embodiments of the present disclosure may be used with any type of processing system, wherein the gap between the pedestal and the gas distribution assembly is controlled. Although various types of gas distribution assemblies (e.g., showerheads) may be employed, embodiments of the present disclosure utilizing space gas distribution assemblies may be particularly useful, and these space gas distribution assemblies have a plurality of substantially parallel gas channels. As used in this specification and the appended claims, the term "substantially parallel" means that the major axis of the gas channels extends in the same general direction. There may be slight flaws in the parallelism of the gas channels. In a binary reaction, a plurality of substantially parallel 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. Gases flowing from the first reactive gas A channel, the second reactive gas B channel, and the purge gas P channel are directed toward the top surface of the wafer. Some gas streams move horizontally across the wafer surface and move out of the processing area through the purge gas P channel. The substrate moving from one end of the gas distribution assembly to the other will in turn be exposed to each of the process gases, which forms a layer on the substrate surface.

[0048] In some embodiments, the gas distribution assembly 220 is a rigid fixed body made of a single injector unit. In one or more embodiments, as Figure 3 As shown, the gas distribution assembly 220 is comprised of multiple individual segments (eg, injector unit 222). A single piece body or a multi-segment body may be used with the various embodiments of the present disclosure described.

[0049] The pedestal assembly 240 is positioned below the gas distribution assembly 220. The pedestal assembly 240 includes a top surface 241 and at least one recess 242 in the top surface 241. The pedestal assembly 240 also has a bottom surface 243 and an edge 244. The at least one recess 242 may be of any suitable shape and size depending on the shape and size of the substrate 60 being processed. Figure 2 In the illustrated embodiment, the groove 242 has a flat bottom to support the bottom of the wafer; however, the bottom of the groove can vary. In some embodiments, the groove has a stepped area around the outer periphery of the groove, and the size of these stepped areas is adjusted to support the outer periphery of the wafer. The amount of the outer periphery of the wafer supported by the steps can vary depending on factors such as the thickness of the wafer and the presence of features already present on the back side of the wafer.

[0050] In some embodiments, Figure 2As shown, the size of the recess 242 in the top surface 241 of the pedestal assembly 240 is adjusted so that the substrate 60 supported in the recess 242 has a top surface 61 that is substantially coplanar with the top surface 241 of the pedestal 240. As used in this specification and the appended claims, the term "substantially coplanar" means that the top surface of the wafer is coplanar with the top surface of the pedestal assembly within ±0.2 mm. In some embodiments, the top surface is coplanar within 0.5 mm, ±0.4 mm, ±0.35 mm, ±0.30 mm, ±0.25 mm, ±0.20 mm, ±0.15 mm, ±0.10 mm, or ±0.05 mm.

[0051] Figure 2 The pedestal assembly 240 includes a support column 260 that can raise, lower, and rotate the pedestal assembly 240. The pedestal assembly may include a heater, or gas lines, or electrical components within the center of the support column 260. The support column 260 can be the main component to increase or decrease the gap between the pedestal assembly 240 and the gas distribution assembly 220, thus moving the pedestal assembly 240 to the appropriate position. The pedestal assembly 240 may also include fine adjustment actuators 262, which can fine-tune the pedestal assembly 240 to create a predetermined gap 270 between the pedestal assembly 240 and the gas distribution assembly 220.

[0052] In some embodiments, the distance of the gap 270 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 about 1 mm.

[0053] The processing chamber 200 shown in the drawings is a turntable type chamber, wherein the base assembly 240 can hold a plurality of substrates 60. Figure 3As shown, the gas distribution assembly 220 may include a plurality of separate injector units 222, each of which is capable of depositing a film on the wafer as the wafer moves under the injector unit. Two pie-shaped injector units 222 are shown as being positioned on approximately opposite sides of the base assembly 240 and above the base assembly 240. This number of injector units 222 is shown only for illustrative purposes. It will be understood that more or less injector units 222 may be included. In some embodiments, there are a sufficient number of pie-shaped injector units 222 to form a shape that conforms to the shape of the base assembly 240. In some embodiments, each independent pie-shaped injector unit 222 may be independently moved, removed and / or replaced without affecting any other injector unit 222. For example, a section may be raised to allow a robot to access the area between the base assembly 240 and the gas distribution assembly 220 to load / unload the substrate 60.

[0054] A processing chamber with multiple gas injectors can be used to process multiple wafers simultaneously so that the wafers experience the same process flow. Figure 4 As shown, the processing chamber 200 has four gas injector assemblies and four substrates 60. At the beginning of the process, the substrate 60 can be positioned between the gas distribution assemblies 220. As shown by the dashed circle below the gas distribution assembly 220, rotating the susceptor assembly 240 by 17 to 45° will cause each substrate 60 between the gas distribution assemblies 220 to move to the gas distribution assembly 220 for film deposition. An additional 45° rotation moves the substrate 60 away from the gas distribution assembly 220. The number of substrates 60 and gas distribution assemblies 220 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, there are 4x wafers processed, where x is an integer value greater than or equal to one. In an exemplary embodiment, the gas distribution assembly 220 includes eight processing areas separated by gas curtains, and the susceptor assembly 240 can hold six wafers.

[0055] Figure 4 The illustrated processing chamber 200 represents only one possible configuration and should not be considered limiting on the scope of the present disclosure. Here, the processing chamber 200 includes a plurality of gas distribution assemblies 220. In the illustrated embodiment, there are four gas distribution assemblies 220 (also referred to as injector assemblies) evenly spaced about the processing chamber 200. The illustrated processing chamber 200 is octagonal; however, one skilled in the art will appreciate that this is one possible shape and should not be considered limiting on the scope of the present disclosure. The illustrated gas distribution assembly 220 is trapezoidal in shape, but could be a single circular component or comprised of multiple pie-shaped segments, such as Figure 3 shown.

[0056] Figure 4 The illustrated embodiment includes a load lock chamber 280, or an auxiliary chamber similar to a buffer station. This chamber 280 is connected to one side of the processing chamber 200, for example, to allow substrates (also referred to as substrates 60) to be loaded / unloaded from the processing chamber 200. A wafer robot may be positioned in the chamber 280 to move the substrates onto the susceptor.

[0057] The rotation of the turntable (e.g., base assembly 240) can be continuous or intermittent (discontinuous). In continuous processing, the wafers are constantly rotated so that they are exposed to each injector in turn. In discontinuous processing, the wafer can move to the injector area and stop, and then move to the area 84 between the injectors and stop. For example, the turntable can rotate so that the wafer moves from the inter-injector area across the injectors (or stops near the injectors) and moves to the next inter-injector area, where the turntable can pause again. The pause between the injectors can provide time for additional processing routines between each layer deposition (e.g., exposure to plasma).

[0058] Figure 5 A section or portion of a gas distribution assembly 220 is shown, which may be referred to as an injector unit. The injector unit 222 may be used independently or in combination with other injector units. For example, Figure 6 As shown, Figure 5 The four injector units 222 are combined to form a single gas distribution assembly 220. (The lines separating the four injector units are not shown for clarity.) Although Figure 5 Although the injector unit 222 of FIG. 1 has the first reactive gas port 225 and the second gas port 235 in addition to the purge gas port 255 and the vacuum port 245 , the injector unit 222 does not require all of these components.

[0059] See also Figure 5 and Figure 6 , the gas distribution assembly 220 according to one or more embodiments may include a plurality of sections (or injector units 222), and each section may be the same or different. The gas distribution assembly 220 is positioned within the processing chamber and includes a plurality of elongated gas ports 225, 235, 245 in the front surface 221 of the gas distribution assembly 220. The plurality of elongated gas ports 225, 235, 245, 255 extend from an area adjacent to the inner periphery 223 toward an area adjacent to the outer periphery 224 of the gas distribution assembly 220. The plurality of gas ports shown include a first reactive gas port 225, a second gas port 235, a vacuum port 245 surrounding each of the first reactive gas port and the second reactive gas port, and a purge gas port 255.

[0060] refer to Figure 5 or Figure 6 In the illustrated embodiment, when the ports are described as extending from around at least the inner peripheral region to around at least the outer peripheral region, however, the ports may extend more than just radially from the inner to the outer regions. Since the vacuum port 245 surrounds the reactive gas port 225 and the reactive gas port 235, the ports may extend in a tangential direction. Figure 5 and Figure 6 In the illustrated embodiment, the wedge-shaped reactive gas ports 225 , 235 are surrounded by vacuum ports 245 on all edges including adjacent the inner peripheral region and the outer peripheral region.

[0061] See also Figure 5 As the substrate moves along path 227, each portion of the substrate surface is exposed to a variety of reactive gases. To follow path 227, the substrate will be exposed to or "see" purge gas port 255, vacuum port 245, first reactive gas port 225, vacuum port 245, purge gas port 255, vacuum port 245, second gas port 235, and vacuum port 245. Thus, in Figure 5 At the end of the illustrated path 227, the substrate has been exposed to the first reactive gas and the second reactive gas to form a layer. The illustrated injector unit 222 forms a quadrant, but may be larger or smaller. Figure 6 The gas distribution assemblies 220 shown may be considered to be connected in series. Figure 3 A combination of four syringe units 222.

[0062] Figure 5 The injector unit 222 of FIG. 2 shows a gas curtain 250 that separates the reactive gases. The term "gas curtain" is used to describe any combination of a gas flow or vacuum that separates the reactive gases so that they do not mix. Figure 5 The illustrated gas curtain 250 includes a portion of the vacuum port 245 adjacent to the first reactive gas port 225, a purge gas port 255 in between, and a portion of the vacuum port 245 adjacent to the second gas port 235. This combination of gas flow and vacuum can be used to prevent or minimize gas phase reactions of the first reactive gas with the second reactive gas.

[0063] See also Figure 6 , the combination of gas flow and vacuum from the gas distribution assembly 220 is separated into a plurality of processing regions 350. The processing regions are roughly defined around the individual gas ports 225, 235, with gas curtains 250 therebetween. Figure 6The embodiment shown constitutes eight separate processing zones with eight separate gas curtains 250 therebetween. The processing chamber can have at least two processing zones. In some embodiments, there are at least three, four, five, six, seven, eight, nine, 10, 11, or 12 processing zones.

[0064] During processing, the substrate may be exposed to more than one processing region 350 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 235, the middle of the substrate will be under the gas curtain 250, and the trailing edge of the substrate will be in the processing region including the first reactive gas port 225.

[0065] The factory interface (such as Figure 4 200, the factory interface may be, for example, a load lock chamber 280. The substrate 60 is shown superimposed above the gas distribution assembly 220 to provide a frame of reference. The substrate 60 may often be placed on a pedestal assembly that should be held on the front surface 221 of the gas distribution assembly 220. The substrate 60 is loaded into the processing chamber 200 via the factory interface onto a substrate support or pedestal assembly (see Figure 4 ). The substrate 60 can be shown positioned within the processing region because the substrate is located adjacent to the first reactive gas port 225 and between the two gas curtains 250a, 250b. Rotating the substrate 60 along the path 227 will move the substrate counterclockwise around the processing chamber 200. Thus, the substrate 60 will be exposed to the first processing region 350a through the eighth processing region 350h, including all processing regions between the first processing region 350a through the eighth processing region 350h.

[0066] Some embodiments of the present disclosure relate to a processing chamber 200 having a plurality of processing regions 350a-350h, wherein each processing region is separated from adjacent regions by a gas curtain 250. For example, in Figure 6 The process chamber shown in FIG. 1 may be any suitable number of gas curtains and process zones within the process chamber, depending on the arrangement of the gas flows. Figure 6 The illustrated embodiment has eight gas curtains 250 and eight processing regions 350a-350h.

[0067] Return to see Figure 1, the processing platform 100 includes a processing chamber 140 connected to the second side 112 of the central transfer station 110. The processing chamber 140 of some embodiments is configured to expose the wafer to a process to process the wafer before and / or after processing in the first batch processing chamber 120. The processing chamber 140 of some embodiments includes an annealing chamber. The annealing chamber can be a furnace annealing chamber or a rapid thermal annealing chamber, or a different chamber configured to hold the wafer at a predetermined temperature and pressure and provide a gas flow to the chamber.

[0068] In some embodiments, the processing platform further includes a second batch processing chamber 130 connected to the third side 113 of the central transfer station 110. The second batch processing chamber 130 can be configured similarly to the first batch processing chamber 120, or can be configured to perform different processes or process a different number of substrates.

[0069] The second batch processing chamber 130 can be the same as or different from the first batch processing chamber 120. In some embodiments, the first batch processing chamber 120 and the second batch processing chamber 130 are configured to perform the same process with the same number of wafers in the same batch time, such that x (the number of wafers in the first batch processing chamber 120) and y (the number of wafers in the second batch processing chamber 130) are the same, and the first batch time and the second batch time (of the second batch processing chamber 130) are the same. In some embodiments, the first batch processing chamber 120 and the second batch processing chamber 130 are configured to have one or more different numbers of wafers (x is not equal to y), different batch times, or both.

[0070] exist Figure 1 In the illustrated embodiment, the processing platform 100 includes a second process chamber 150 coupled to the fourth side 114 of the central transfer station 110. The second process chamber 150 may be the same as the process chamber 140 or different.

[0071] The processing platform 100 may include a controller 195 (the connection is not shown) connected to the robot 117. The controller 195 may be configured to move the wafer between the process chamber 140 and the first batch processing chamber 120 using the first arm 118 of the robot 117. In some embodiments, the controller 195 is also configured to move the wafer between the second process chamber 150 and the second batch processing chamber 130 using the second arm 119 of the robot 117.

[0072] In some embodiments, the controller 195 is connected to the pedestal assembly 240 and the gas distribution assembly 220 of the processing chamber 200. The controller 195 can be configured to rotate the pedestal assembly 240 around the central axis. The controller can also be configured to control the flow of gases in the gas ports 225, 235, 245, 255. In some embodiments, the first reactive gas port 225 provides a flow of a metal precursor. In some embodiments, the second reactive gas port 235 provides a flow of a reactant. In some embodiments, other gas ports (not labeled) can provide a flow of plasma. The first reactive gas port 225, the second reactive gas port 235, and the other reactive gas ports (not labeled) can be arranged in any processing order.

[0073] The processing platform 100 may also include a first buffer station 151 connected to the fifth side 115 of the central transfer station 110 and / or a second buffer station 152 connected to the sixth side 116 of the central transfer station 110. The first buffer station 151 and the second buffer station 152 may perform the same or different functions. For example, the buffer station may hold a cassette of wafers that have been processed and returned to the initial cassette, or the first buffer station 151 may hold unprocessed wafers that will be moved to the second buffer station 152 after processing. In some embodiments, one or more buffer stations are configured to pre-process, pre-heat, or clean wafers before and / or after processing.

[0074] In some embodiments, the controller 195 is configured to use the first arm 118 of the robot 117 to move the wafer between the first buffer station 151 and the one or more processing chambers 140 and the first batch processing chamber 120. In some embodiments, the controller 195 is configured to use the second arm 119 of the robot 117 to move the wafer between the second buffer station 152 and the one or more second processing chambers 150 or the second batch processing chamber 130.

[0075] The processing platform 100 may also include one or more slit valves 160 between the central transfer station 110 and any of the processing chambers. In the illustrated embodiment, there are slit valves 160 between each of the processing chambers 120, 130, 140, 150 and the central transfer station 110. The slit valves 160 may be opened or closed to isolate the environment within the processing chamber from the environment within the central transfer station 110. For example, if a processing chamber will generate plasma during processing, it may be useful to close the slit valve for that processing chamber to prevent stray plasma from damaging a robot in the transfer station.

[0076] In some embodiments, the process chambers are not easily removable from the central transfer station 110. To allow maintenance to be performed on any of the process chambers, each process chamber may further include a plurality of access doors 170 on the side of the process chamber. The access doors 170 allow for manual access to the process chambers without removing the process chambers from the central transfer station 110. In the illustrated embodiment, each side of each process chamber has an access door 170 in addition to the side connected to the transfer station. Including so many access doors 170 can complicate the construction of the process chambers employed because the hardware within the chambers will need to be configured to be accessible through these doors.

[0077] The processing platform of some embodiments includes a water tank 180 connected to the central transfer station 110. The water tank 180 can be configured to provide coolant to any or all processing chambers. Although referred to as a "water" tank, those skilled in the art will understand that any coolant can be used.

[0078] In some embodiments, the size of the processing platform 100 allows for connection to chamber power through a single power connector 190. The single power connector 190 is attached to the processing platform 100 to provide power to each processing chamber and the central transfer station 110.

[0079] The processing platform 100 can be connected to a factory interface 102 to allow wafers or wafer cassettes to be loaded into the processing platform 100. Robots 103 within the factory interface 102 can move wafers or cassettes into and out of the buffer stations 151, 152. Wafers or cassettes can be moved within the processing platform 100 by robots 117 in a central transfer station 110. In some embodiments, the factory interface 102 is a transfer station of another cluster tool.

[0080] In some embodiments, the processing platform 100 or the first batch processing chamber 120 is connected to a controller. The controller can be the same controller 195 or a different controller. The controller can be coupled to the pedestal assembly and the gas distribution assembly of the first batch processing chamber 120 and have one or more configurations. The configurations can include, but are not limited to, a first configuration for rotating the pedestal assembly around a central axis, a second configuration for providing a flow of a metal precursor to a processing region, a third configuration for providing a flow of a reactant to a processing region, and a fourth configuration for providing a plasma in a processing region.

[0081] Figure 7A generalized method for forming a metal film on a substrate according to one or more embodiments of the present disclosure is depicted. Method 700 generally begins at 702, wherein a substrate on which a metal film is to be formed is provided and the substrate is placed in a processing chamber. As used herein, "substrate surface" refers to any substrate surface on which a layer may be formed. The substrate surface may have one or more features formed therein, one or more layers formed thereon, and combinations thereof. The substrate (or substrate surface) may be pre-processed prior to depositing the metal film, for example, by polishing, etching, reduction, oxidation, halogenation, hydroxylation, annealing, baking, or the like.

[0082] The substrate may be any substrate capable of depositing materials thereon, such as a silicon substrate, a III-V compound substrate, a silicon germanium (SiGe) substrate, an epitaxial substrate, a silicon-on-insulator (SOI) substrate, a display substrate, a solar array, a solar panel, a light emitting diode (LED) substrate, a semiconductor wafer, or the like, a display substrate such as a liquid crystal display (LCD), a plasma display, an electroluminescence (EL) lamp display. In some embodiments, one or more additional layers may be disposed on the substrate such that a metal film may be formed at least partially on these additional layers. For example, in some embodiments, a layer comprising a metal, a nitride, an oxide, or the like, or a combination of the foregoing, may be disposed on the substrate and may have a metal film formed on such one or more layers.

[0083] The substrate is optionally exposed to a barrier compound at 703. This processing step is described more fully below and can be used to control the selectivity of the deposition process to substrates including metallic surfaces and dielectric surfaces.

[0084] At 704, a metal film is formed on the substrate. The metal film may be formed via a cyclic deposition process such as atomic layer deposition (ALD), or a similar process. In some embodiments, forming the metal film via a cyclic deposition process may generally include exposing the substrate to two or more process gases separately. In a time-domain ALD embodiment, exposure to each process gas is separated by a time delay / pause to allow components of the process gas to adhere to and / or react on the substrate surface. Alternatively or in combination, in some embodiments, a purge may be performed before and / or after exposing the substrate to the process gas, wherein an inert gas is used to perform the purge. For example, a first process gas may be provided to a process chamber, followed by a purge with an inert gas. Next, a second process gas may be provided to the process chamber, followed by a purge with an inert gas. In some embodiments, an inert gas may be provided continuously to the process chamber, and the first process gas may be dosed or pulsed into the process chamber, followed by a dosed or pulsed into the process chamber. In such an embodiment, a delay or pause may occur between dosing of the first process gas and the second process gas, thus allowing the inert gas to continue to flow to purge the processing chamber between dosing of the process gases.

[0085] In spatial ALD embodiments, exposure to each process gas occurs simultaneously to different portions of the substrate, such that one portion of the substrate is exposed to a first reactive gas while a different portion of the substrate is exposed to a second reactive gas (if only two reactive gases are used). The substrate is moved relative to the gas delivery system such that each point on the substrate is sequentially exposed to both the first and second reactive gases. In any embodiment of a time-domain ALD or spatial ALD process, the sequence may be repeated until a predetermined layer thickness is formed on the substrate surface.

[0086] As used herein, "pulsing" or "dosing" is intended to refer to the amount of source gas that is intermittently or discontinuously introduced into a processing chamber. Depending on the duration of the pulse, the amount of a particular compound in each pulse may vary over time. A particular process gas may include a single compound or a mixture / combination of two or more compounds, such as the process gases described below.

[0087] The duration for each pulse / dose is variable and can be adjusted to accommodate, for example, the volume capacity of the processing chamber and the capacity of the vacuum system coupled to the processing chamber. In addition, the dosing time of the treatment gas can vary according to the flow rate of the treatment gas, the temperature of the treatment gas, the type of control valve, the type of treatment chamber used, and the ability of the components of the treatment gas to be adsorbed on the substrate surface. The dosing time can also vary based on the type of layer formed and the geometry of the device formed. The dosing time should be long enough to provide enough adsorption / chemical adsorption to the entire surface of the substrate and form a volume of the compound of the treatment gas component layer thereon.

[0088] The process of forming a metal film may begin by exposing the substrate to a first reactive gas at 704. As shown at 706, the first reactive gas includes an alkyl halide and is exposed to the substrate for a first period of time.

[0089] Alkyl halides can be any suitable reactants for adsorbing a halogen layer on a substrate for later reaction. In some embodiments, the alkyl halide comprises carbon and a halogen. In some embodiments, the halogen comprises bromine or iodine. In some embodiments, the halogen is insoluble in the metal film. As used in this regard, the halogen insoluble in the metal film is contained in a metal film of less than or equal to about 2%, less than or equal to about 1%, or less than or equal to about 0.5% on an atomic basis. In some embodiments, the alkyl halide has the general formula RX, wherein R is an alkyl, alkenyl, aryl, or other carbon-containing group. In some embodiments, R comprises one to two, one to four, or one to six carbon atoms. In some embodiments, the alkyl halide comprises the following substances or is substantially composed of the following substances: iodoethane (H5C2I) or diiodomethane (CH2I2). As used in this regard, the alkyl halide substantially composed of the mentioned species comprises greater than 95%, 98%, 99% or 99.5% of the mentioned species on a molar basis, excluding any inert diluent gas.

[0090] Alkyl halide is delivered to the processing chamber as the gas containing alkyl halide. Gas containing alkyl halide can be provided by one or more pulses or continuously. The flow rate of the gas containing alkyl halide can be any suitable flow rate, including but not limited to, flow rate in the range of about 1 to about 5000sccm, or in the range of about 2 to about 4000sccm, or in the range of about 3 to about 3000sccm, or in the range of about 5 to about 2000sccm. Gas containing alkyl halide can be provided at any suitable pressure, including but not limited to, pressure in the range of about 5mTorr to about 25Torr, or in the range of about 100mTorr to about 20Torr, or in the range of about 5Torr to about 20Torr, or in the range of about 50mTorr to about 2000mTorr, or in the range of about 100mTorr to about 1000mTorr, or in the range of about 200mTorr to about 500mTorr.

[0091] The period of time that the substrate is exposed to the gas containing the alkyl halide can be any suitable amount of time necessary to allow the alkyl halide to form a sufficient adsorption layer atop the substrate surface. For example, the process gas can flow into the process chamber for a period of about 0.1 seconds to about 90 seconds. In some time-domain ALD processes, the gas containing the alkyl halide exposes the substrate surface for a period in the range of about 0.1 seconds to about 90 seconds, or in the range of about 0.5 seconds to about 60 seconds, or in the range of about 1 second to about 30 seconds, or in the range of about 2 seconds to about 25 seconds, or in the range of about 3 seconds to about 20 seconds, or in the range of about 4 seconds to about 15 seconds, or in the range of about 5 seconds to about 10 seconds.

[0092] In some embodiments, an inert gas may be additionally provided to the processing chamber simultaneously with the gas containing the alkyl halide. The inert gas may be mixed with the gas containing the alkyl halide (e.g., as a diluent gas) or provided separately, and may be pulsed or have a constant flow. In some embodiments, the inert gas is flowed into the processing chamber at a constant flow in the range of about 1 to about 10000 sccm. The inert gas may be any inert gas, for example, such as argon, helium, neon, or a combination thereof.

[0093] The substrate temperature during deposition can be controlled, for example, by setting the temperature of the substrate support or pedestal. In some embodiments, the substrate is held at a temperature in the range of about 0°C to about 600°C, or in the range of about 25°C to about 500°C, or in the range of about 50°C to about 450°C, or in the range of about 100°C to about 400°C, or in the range of about 200°C to about 400°C, or in the range of about 250°C to about 350°C. In some embodiments, the substrate is maintained at a temperature below the decomposition temperature of the metal precursor. In some embodiments, the substrate is maintained at a temperature below the decomposition temperature of the alkyl halide. In some embodiments, the substrate is maintained at a temperature between the decomposition temperature of the alkyl halide and the decomposition temperature of the metal precursor.

[0094] In one or more embodiments, the substrate is maintained at a temperature of less than or equal to about 400° C., or less than or equal to about 350° C., or less than or equal to about 300° C. In one or more embodiments, the substrate is maintained at a temperature greater than or equal to about 250° C., or greater than or equal to about 300° C., or greater than or equal to about 350° C. In some embodiments, the substrate is maintained at a temperature of about 280° C.

[0095] In addition to the foregoing, additional process parameters may be adjusted when exposing the substrate to the gas containing the alkyl halide. For example, in some embodiments, the processing chamber may be maintained at a pressure of about 0.2 to about 100 Torr, or in a range of about 0.3 to about 90 Torr, or in a range of about 0.5 to about 80 Torr, or in a range of about 1 to about 50 Torr.

[0096] Next, at 708, the processing chamber (especially the time-domain ALD) may be purged with an inert gas. (This operation may not be required in the spatial ALD process due to the presence of a gas curtain separating the reactive gases.) The inert gas may be any inert gas, for example, such as argon, helium, neon, or the like. In some embodiments, the inert gas may be the same, or alternatively, may be different from the inert gas provided to the processing chamber during the exposure of the substrate to the gas containing the alkyl halide at 706. In embodiments where the inert gas is the same, the purge may be performed by diverting the first processing gas from the processing chamber, which allows the inert gas to flow through the processing chamber, purging any excess first processing gas components or reaction byproducts of the processing chamber. In some embodiments, the inert gas used in combination with the first processing gas described above may be provided at the same flow rate, or in some embodiments, the flow rate may be increased or decreased. For example, in some embodiments, the inert gas may be provided to the processing chamber at a flow rate of about 0 to about 10,000 sccm to purge the processing chamber. In spatial ALD, a purge gas curtain is maintained between flows of reactive gases, and purging the process chamber may not be necessary. In some embodiments of a spatial ALD process, the process chamber or a region of the process chamber may be purged with an inert gas.

[0097] The flow of the inert gas may facilitate removal of any excess first process gas components and / or excess reaction byproducts from the processing chamber to prevent unwanted gas phase reactions of the first and second process gases.

[0098] Next, at 710, the substrate is exposed to a second process gas for a second period of time. The second process gas includes a metal precursor that reacts with the adsorbed layer of halogen on the substrate surface to deposit a metal film. The second reactive gas may also be referred to as a metal precursor gas.

[0099] The metal precursor can be any suitable precursor to react with the halogen layer adsorbed on the substrate. In some embodiments, the metal precursor comprises a metal center and one or more ligands. In some embodiments, the metal center comprises one or more metal atoms. In other words, in some embodiments, the metal precursor is one or more of a dimer, a trimer, or a tetramer.

[0100] The metal precursor can be any suitable precursor having a decomposition temperature higher than the deposition temperature. In some embodiments, the metal precursor contains substantially no oxygen or nitrogen atoms. Thus, in these embodiments, the metal precursor does not contain carbonyl, oxo, amine, or imine ligands. Within these parameters, the number of ligands on the metal precursor and the type of ligands can vary based on, for example, the oxidation state of the metal atom. The metal precursor can be a homoleptic or a heteroleptic. In some embodiments, the metal precursor contains at least one ligand containing an optionally alkyl-substituted cyclopentadiene (Cp) ring. In some embodiments, the metal precursor contains at least one ligand containing an optionally alkyl-substituted benzene ring. In some embodiments, the metal precursor contains at least one p-isopropyltoluene ligand. In some embodiments, the metal precursor contains at least one ligand containing an open or closed diene. In some embodiments, the metal precursor comprises at least one 1,3-butadiene ligand. In some embodiments, the metal precursor comprises at least one 1,5-hexadiene ligand. In some embodiments, the metal precursor comprises at least one aromatic ligand. In some embodiments, at least one aromatic ligand comprises a benzene ring. In some embodiments, the benzene ring comprises at least one organic substituent comprising a carbon atom in the range of 1 to 6. In some embodiments, the aromatic ligand comprises at least one ethylbenzene ligand. In some embodiments, the metal precursor comprises or consists essentially of bis(ethylbenzene) molybdenum. In some embodiments, the metal precursor comprises or consists essentially of 1,5-hexadiene-p-isopropyltoluene ruthenium.

[0101] The metal of the metal precursor corresponds to the metal of the deposited metal film. In some embodiments, the metal is selected from molybdenum, ruthenium, cobalt, copper, platinum, nickel or tungsten. In some embodiments, the metal of the metal precursor has an oxidation state of 0. In other words, in some embodiments, the metal precursor comprises a zero-valent metal complex.

[0102] Additional processing parameters may be adjusted when exposing the substrate to the metal precursor gas. For example, in some embodiments, the processing chamber may be maintained at a pressure of about 0.2 to about 100 Torr, or in a range of about 0.3 to about 90 Torr, or in a range of about 0.5 to about 80 Torr, or in a range of about 1 to about 50 Torr.

[0103] Metal precursor is delivered to the processing chamber as metal precursor gas.Metal precursor gas can be provided with one or more pulses or continuously.The flow rate of metal precursor gas can be any suitable flow rate, including but not limited to flow rate in the range of about 1 to about 5000sccm, or in the range of about 2 to about 4000sccm, or in the range of about 3 to about 3000sccm, or in the range of about 5 to about 2000sccm.Metal precursor gas can be provided under any suitable pressure, including but not limited to, pressure in the range of about 5mTorr to about 25Torr, or in the range of about 100mTorr to about 20Torr, or in the range of about 5Torr to about 20Torr, or in the range of about 50mTorr to about 2000mTorr, or in the range of about 100mTorr to about 1000mTorr, or in the range of about 200mTorr to about 500mTorr.

[0104] The period of time that the substrate is exposed to the metal precursor gas may be any suitable amount of time necessary to allow the metal precursor to react with the halogen adsorbed on the substrate surface. For example, the process gas may flow into the process chamber for a period of about 0.1 seconds to about 90 seconds. In some time-domain ALD processes, the metal precursor gas exposes the substrate surface for a period in the range of about 0.1 seconds to about 90 seconds, or in the range of about 0.5 seconds to about 60 seconds, or in the range of about 1 second to about 30 seconds, or in the range of about 2 seconds to about 25 seconds, or in the range of about 3 seconds to about 20 seconds, or in the range of about 4 seconds to about 15 seconds, or in the range of about 5 seconds to about 10 seconds.

[0105] In some embodiments, an inert gas may additionally be provided to the processing chamber simultaneously with the metal precursor gas. The inert gas may be mixed with the metal precursor gas (e.g., as a diluent gas) or provided separately and may be pulsed or have a constant flow. In some embodiments, the inert gas is flowed into the processing chamber at a constant flow in the range of about 1 to about 10,000 sccm. The inert gas may be any inert gas, such as, for example, argon, helium, neon, or a combination thereof.

[0106] Next, at 712, the process chamber may be purged with an inert gas. The inert gas may be any inert gas, such as, for example, argon, helium, neon, or the like. In some embodiments, the inert gas may be the same, or alternatively, may be different from the inert gas provided to the process chamber during a previous process routine. In embodiments where the inert gas is the same, the purge may be performed by diverting a second process gas from the process chamber, which allows the inert gas to flow through the process chamber, purging the process chamber of any excess second process gas components or reaction byproducts. In some embodiments, the inert gas used in conjunction with the second process gas described above is provided at the same flow rate, or in some embodiments, the flow rate may be increased or decreased. For example, in some embodiments, the inert gas may be provided to the process chamber at a flow rate of greater than 0 to about 10,000 seem to purge the process chamber.

[0107] although Figure 7 The general embodiment of the processing method shown includes only two pulses of reactive gas, it will be understood that this is merely exemplary and that additional pulses of reactive gas may be used. In some embodiments, the method is performed without using an oxygen-containing reactive gas. The subprocess of 704 includes cycles. The cycles may be performed in any order as long as the reactive gases are separated by purging of the processing chamber. In some embodiments, the metal film is heated to a temperature greater than or equal to about 100°C. Greater than or equal to approximately Greater than or equal to approximately Greater than or equal to approximately Greater than or equal to approximately Greater than or equal to approximately Greater than or equal to approximately Greater than or equal to approximately Greater than or equal to approximately or greater than or equal to approximately rate of deposition.

[0108] Without the use of plasma reactants, the deposition process is performed as a thermal process. In other words, in some embodiments, the method is performed without plasma.

[0109] Next, at 714, it is determined whether the metal film has reached a predetermined thickness. If the predetermined thickness has not been reached, method 700 returns to 704 to continue forming the metal film until the predetermined thickness is reached. Once the predetermined thickness has been reached, method 700 may end or proceed to 716 for optional further processing (e.g., bulk deposition of another metal film). In some embodiments, the metal film may be deposited to form about to about The total layer thickness is about to about Or in some embodiments, about to about

[0110] In some embodiments, the metal layer contains greater than or equal to about 75 atomic % molybdenum, or greater than or equal to about 80 atomic % molybdenum, or greater than or equal to about 85 atomic % molybdenum, or greater than or equal to about 90 atomic % molybdenum, or greater than or equal to about 95 atomic % molybdenum.

[0111] In some embodiments, the metal layer contains less than or equal to about 10 atomic % oxygen, or less than or equal to about 9 atomic % oxygen, or less than or equal to about 8 atomic % oxygen, or less than or equal to about 7 atomic % oxygen, or less than or equal to about 6 atomic % oxygen, or less than or equal to about 5 atomic % oxygen, or less than or equal to about 4 atomic % oxygen, or less than or equal to about 3 atomic % oxygen.

[0112] In some embodiments, the metal layer includes iodine in a range of about 0.02 to about 5 atomic %, or less than or equal to about 1 atomic % iodine.

[0113] In some embodiments, the metal layer contains less than or equal to about 20 atomic % carbon, or less than or equal to about 15 atomic % carbon, or less than or equal to about 10 atomic % carbon, or less than or equal to about 5 atomic % carbon.

[0114] In some embodiments, the metal layer includes greater than or equal to about 90 atomic % molybdenum, less than or equal to about 3 atomic % oxygen, less than or equal to about 1 atomic % iodine, and less than or equal to about 10 atomic % carbon.

[0115] In some embodiments, the metal layer has a resistivity of about 40 μohm-cm or less, or about 35 μohm-cm or less, or about 30 μohm-cm or less, or about 25 μohm-cm or less, or about 20 μohm-cm or less. In some embodiments, the metal layer comprises molybdenum and has a resistivity of about 40 μohm-cm or less, or about 35 μohm-cm or less, or about 30 μohm-cm or less, or about 25 μohm-cm or less, or about 20 μohm-cm or less.

[0116] In some embodiments, the metal film is further processed by annealing the metal film. Without being bound by theory, it is believed that annealing the film at high temperature in an Ar or H2 atmosphere reduces carbon and halogen impurities in the metal film. In some embodiments, the metal film is annealed in an atmosphere containing argon or hydrogen (H2) to reduce the atomic concentration of carbon and / or halogen impurities.

[0117] Metal films deposited by some embodiments are smoother than films deposited by known oxygen-based deposition processes. In some embodiments, the metal film has a surface roughness of less than or equal to about 10%, less than or equal to about 8%, less than or equal to about 5%, or less than or equal to about 2% of the thickness of the metal film.

[0118] The purity of the metal film is high. In some embodiments, the metal film has a carbon content of less than or equal to about 2%, less than or equal to about 1%, or less than or equal to about 0.5% carbon on an atomic basis. In some embodiments, the metal film has a halogen content of less than or equal to about 1% or less than or equal to about 0.5% halogen on an atomic basis. In some embodiments, the metal film has a purity of greater than or equal to about 95%, greater than or equal to about 97%, greater than or equal to about 99%, greater than or equal to about 99.5%, or greater than or equal to about 99.9% metal atoms on an atomic basis.

[0119] Some embodiments of the present disclosure selectively deposit a first metal film on a second metal surface in preference to a first dielectric surface. These methods are similar to method 700 as described above, except that a substrate is provided that includes a first dielectric surface and a second metal surface. The first metal (of the metal film) and the second metal (of the substrate surface) may be the same metal or may be different metals. In some embodiments, the first metal is molybdenum, ruthenium, cobalt, copper, platinum, nickel, or tungsten, and the second metal is tungsten, cobalt, or copper.

[0120] The first dielectric surface can be formed of any suitable dielectric material. In some embodiments, the dielectric material comprises nitrogen or oxygen atoms. Without being limited by theory, it is believed that these materials react with the alkyl halide and prevent the halogen from adsorbing onto the substrate surface so as to catalyze the reaction with the metal precursor. As a result, little (if any) metal film is formed on the dielectric surface.

[0121] In some embodiments, the deposition temperature is below the decomposition temperature of the alkyl halide. Again, without being bound by theory, it is believed that if the alkyl halide decomposes, the halogen will be available to react with the metal precursor on all surfaces (regardless of composition), which results in the deposition of metal films on all substrate surfaces (including dielectric surfaces). In some embodiments, the deposition temperature is at or above the decomposition temperature of the alkyl halide.

[0122] Some embodiments of the present disclosure selectively deposit a first metal film on a first dielectric surface in preference to a second metal surface. These methods are similar to method 700 as described above, except that a substrate is provided comprising a first dielectric surface and a second metal surface, and at 703, the substrate is exposed to a barrier compound.

[0123] At 703, a substrate comprising at least a second metal surface and a first dielectric surface is exposed to a blocking compound. The blocking compound may be any suitable compound for blocking deposition on the second metal surface. In some embodiments, the blocking compound comprises at least one triple bond between two carbon atoms. In other words, in some embodiments, the blocking compound comprises an alkyne. In some embodiments, the blocking compound has the general formula R'≡R". In some embodiments, R' and R" are the same. In some embodiments, R' and / or R" are alkyl or other carbon-containing groups. In some embodiments, the blocking compound comprises 4-12 carbon atoms. In some embodiments, R' and / or R" are linear. In some embodiments, R' and / or R" are branched. In some embodiments, the blocking compound comprises 3-hexyne.

[0124] The first metal (of the metal film) and the second metal (of the substrate surface) may be the same metal or may be different metals. In some embodiments, the first metal is molybdenum, ruthenium, cobalt, copper, platinum, nickel or tungsten, and the second metal is tungsten, cobalt or copper.

[0125] The first dielectric surface can be formed of any suitable dielectric material. In some embodiments, the dielectric material comprises nitrogen or oxygen atoms.

[0126] As mentioned previously, in some embodiments, the deposition temperature is at or above the decomposition temperature of the alkyl halide. In some embodiments, the deposition temperature is greater than or equal to about 250°C, greater than or equal to about 260°C, greater than or equal to about 270°C, greater than or equal to about 280°C, greater than or equal to 290°C, or greater than or equal to about 300°C. In some embodiments, the deposition temperature is in the range of about 250°C to about 450°C, or in the range of about 300°C to about 400°C. In some embodiments, the deposition temperature is about 350°C.

[0127] As mentioned previously, without being bound by theory, it is believed that these materials react with the alkyl halides and prevent the halogen from adsorbing onto the substrate surface in order to catalyze the reaction with the metal precursor. Thus, little, if any, metal film is formed on the dielectric surface.

[0128] However, when the deposition temperature is above the decomposition temperature of the alkyl halide, the halogen atoms are deposited over the entire substrate surface, thereby allowing deposition on dielectric surfaces. In some embodiments, the metal surface is blocked by the blocking compound to allow little, if any, metal film to form on the metal surface. Thus, the deposition of the metal film has selectivity for dielectric surfaces over metal surfaces.

[0129] Generally speaking, the deposition of high purity metal films can be understood as follows. A substrate maintained at a deposition temperature is exposed to an alkyl halide (RX) to adsorb R and X on the substrate, wherein R is a carbon-containing group and X is a halogen. R is RR or R - The substrate is exposed to a metal precursor, ML, where M is a metal and L is a ligand. ML reacts with the adsorbed X to form MX on the substrate surface, thus releasing L. MX reacts with other MX moieties on the substrate to form MM. This reaction can produce XX or X - . XX can be desorbed and purged. X - May remain on the substrate to further react with ML.

[0130] According to the inventors, this general mechanism relies on several premises. First, X is insoluble in M. Without being limited by theory, the insolubility of X gives that no appreciable amount of X will be found in the final metal film. Although it is possible to ignore this premise (for example, using a halogen that is soluble in M), it is believed that the use of a halogen (X) that is soluble in M ​​provides a metal film with lower purity. Secondly, in terms of bond strength, ML is weaker than MX, and MX is weaker than MM. Furthermore, without being limited by theory, these thermodynamic relationships ensure that the reactions mentioned above are thermodynamically favorable. Finally, ML is thermally stable at the deposition temperature. In other words, the thermal decomposition temperature of the metal precursor is higher than the deposition temperature. The theory of this article explains that if the metal precursor decomposes, the deposited film will contain a appreciable amount of precursor ligand L, which is generally regarded as a carbon impurity.

[0131] The inventors have unexpectedly discovered a process comprising a metal precursor, an alkyl halide, and processing conditions that meet all of the above requirements for depositing high purity metal films.

[0132] Furthermore, the inventors have surprisingly discovered that if the deposition temperature is below the thermal decomposition temperature of the alkyl halide, the deposition process is selective for metallic surfaces over dielectric surfaces without the need to use a barrier layer.

[0133] Additionally, the inventors have surprisingly discovered that if the deposition temperature is at or above the thermal decomposition temperature of the alkyl halide, the deposition process can be made selective by exposing the metal surface to a small alkyne blocking compound.

[0134] Some embodiments of the present disclosure advantageously provide methods for depositing conformal metal films on substrates containing high aspect ratio structures. As used in this regard, the term "conformal" means that the thickness of the metal film across the surface of the substrate is uniform. As used in this specification and the appended claims, the term "substantially conformal" means that the thickness of the metal film does not vary by more than about 10%, 5%, 2%, 1%, or 0.5% relative to the average thickness of the film. In other words, a substantially conformal film has a conformality greater than about 90%, 95%, 98%, 99%, or 99.5%.

[0135] One or more embodiments of the present disclosure relate to a memory device comprising a molybdenum conductive layer. In some embodiments, the molybdenum conductive layer comprises greater than or equal to about 90 atomic % molybdenum, less than or equal to about 3 atomic % oxygen, less than or equal to about 1 atomic % iodine, and less than or equal to about 10 atomic % carbon, and a resistivity of less than or equal to about 40 μohm-cm.

[0136] In some embodiments, the platinum conductive layer is formed on the barrier layer. The barrier layer of some embodiments has a thickness less than or equal to about or In some embodiments, a molybdenum conductive layer is formed on a substrate without an intermediate barrier layer.

[0137] The above disclosure is related to the deposition of metal films by continuous pulses of reactants. The following disclosure is related to the deposition of metal films by a simultaneous or constant flow process. In some embodiments, the continuous pulse method is an ALD method. In some embodiments, the simultaneous or constant flow method is a CVD method. Although the processing steps are different, many of the reactants and processing parameters are similar.

[0138] Figure 8 Depicted is a generalized method 800 for forming a metal film on a substrate in accordance with one or more embodiments of the present disclosure. Fig. 9 An exemplary substrate for processing according to one or more embodiments of the present disclosure is depicted. Method 800 generally begins at 810 where a substrate 900 on which a metal film is to be formed is provided and placed into a processing chamber.

[0139] See also Fig. 9 , an exemplary substrate 900 is shown. In some embodiments, the substrate 900 has a substrate surface 905 having at least one feature 910 therein. The feature 910 has sidewalls 912, 914 and a bottom 916. In some embodiments, a dielectric material 920 forms the sidewalls 912, 914, and a metal material 930 forms the bottom 16.

[0140] In some embodiments, substrate 900 may undergo a pre-processing step. At 815, the substrate may optionally have one or more layers formed on a surface of the substrate.

[0141] In some embodiments, a metal nitride liner is deposited in feature 910. In some embodiments, the metal nitride liner comprises titanium nitride. In some embodiments, the metal nitride liner has a thickness of about to about In some embodiments, the metal nitride liner has a thickness in the range of about or about Thickness.

[0142] In some embodiments, the seed layer is deposited on the substrate surface. In some embodiments, the seed layer is a conformal layer. In some embodiments, the seed layer is continuous. In some embodiments, the thickness of the seed layer is in the range of about 1 nm to about 5 nm, or in the range of from about 1 nm to about 4 nm. In some embodiments, the seed layer comprises a ruthenium layer deposited by a known atomic layer deposition method. In some embodiments, the seed layer is deposited by an ALD cycle comprising a ruthenium precursor exposure and an alkyl halide exposure with a purge in between. In some embodiments, the seed layer is deposited by an ALD cycle comprising a ruthenium precursor exposure and an ammonia plasma exposure with a purge in between.

[0143] The substrate is optionally exposed to a barrier compound at 820. This process step is described more fully below and can be used to control the selectivity of a deposition process to a substrate including metallic surfaces and dielectric surfaces.

[0144] At 830, a metal film is formed on the substrate. The process of forming the metal film at 830 may begin by impregnating the substrate with a catalytic gas. As shown at 840, the catalytic gas includes an alkyl halide and is exposed to the substrate for a first period of time.

[0145] The alkyl halide may be any suitable reactant that is adsorbed as a layer on the substrate for later reaction. In other words, the substrate is immersed in the alkyl halide to form an activated substrate surface. The alkyl halide is described above and elsewhere herein.

[0146] The alkyl halide may be provided to the processing chamber in one or more pulses or continuously. In some embodiments, the alkyl halide is provided together with an inert carrier gas and is referred to as a gas containing an alkyl halide. The flow rate and pressure of the alkyl halide or the gas containing an alkyl halide may be any suitable value. The exemplary flow rates and pressures disclosed elsewhere herein for the gas containing an alkyl halide may also be applied in this embodiment.

[0147] The period of time during which the substrate is immersed in the alkyl halide can be any suitable amount of time necessary to allow the alkyl halide to form a sufficient adsorption layer on the substrate surface. For example, the alkyl halide can be allowed to immerse the substrate for a period greater than about 3 seconds or greater than about 5 seconds. In some embodiments, the immersion period is in the range of about 3 seconds to about 60 seconds.

[0148] In some embodiments, an inert gas may be additionally provided to the processing chamber simultaneously with the gas containing the alkyl halide. The inert gas may be mixed with the alkyl halide (e.g., as a diluent gas) or provided separately and may be pulsed or have a constant flow. The inert gas may be any inert gas, such as, for example, argon, helium, neon, or a combination thereof.

[0149] Next, at 850, the substrate is exposed to a second process gas for a second period of time. The second process gas includes a metal precursor that reacts with the adsorbed layer of alkyl halide or halogen on the substrate surface to deposit a metal film. The second reactive gas may also be referred to as a metal precursor gas.

[0150] The metal precursor may be any suitable precursor to react with the adsorbed alkyl halide layer or halogen layer on the substrate. Suitable metal precursors are described elsewhere herein.

[0151] The metal precursor is delivered to the processing chamber as a metal precursor gas. The metal precursor gas can be provided in one or more pulses or continuously. The flow rate and pressure of the metal precursor gas can be any suitable flow rate and pressure. Exemplary values ​​for flow rates and pressures are discussed elsewhere herein.

[0152] The period of time that the substrate is exposed to the metal precursor gas can be any suitable amount of time necessary to allow the metal precursor to react with the halogen adsorbed on the substrate surface. For example, the process gas can flow into the processing chamber for a period of greater than or equal to about 60 seconds. In some embodiments, the period of exposure to the metal precursor is about 100 seconds, about 200 seconds, about 300 seconds, about 400 seconds, or about 500 seconds.

[0153] The temperature of the substrate during exposure to the metal precursor can be controlled, for example, by setting the temperature of the substrate support or pedestal. This temperature is also referred to as the deposition temperature. In some embodiments, the substrate is maintained at a temperature below the decomposition temperature of the metal precursor. In some embodiments, the substrate is maintained at a temperature below the decomposition temperature of the alkyl halide. In some embodiments, the substrate is maintained at a temperature between the decomposition temperature of the alkyl halide and the decomposition temperature of the metal precursor.

[0154] In one or more embodiments, the substrate is maintained at a temperature of less than or equal to about 400° C., or less than or equal to about 350° C., or less than or equal to about 300° C., or less than or equal to about 250° C., or less than or equal to about 200° C. In one or more embodiments, the substrate is maintained at a temperature of greater than or equal to about 150° C., or greater than or equal to about 200° C., or greater than or equal to about 250° C., or greater than or equal to about 300° C., or greater than or equal to about 350° C. In some embodiments, the substrate is maintained at a temperature of about 225° C. or about 280° C.

[0155] The deposition process is performed as a thermal process without the use of plasma reactants. In other words, the method is performed without plasma.

[0156] Next, at 860, it is determined whether the metal film has reached a predetermined thickness. If the predetermined thickness has not been reached, method 800 returns to 850 to continue exposing the substrate to the metal precursor until the predetermined thickness is reached. Once the predetermined thickness has been reached, method 800 may end or proceed to 870 for optional further processing. In some embodiments, the metal film may be deposited to form about to about The total layer thickness is about to about Or in some embodiments, about to about

[0157] Some embodiments of the present disclosure selectively deposit a metal film on a metal surface in preference to a first dielectric surface. These methods are similar to method 800 as described above. A substrate is provided that includes a dielectric surface and a metal surface. In some embodiments, Fig. 9 The substrate is shown processed to selectively form a bottom-up gap fill on the metal surface at the bottom 916 of the feature 910 .

[0158] The metal of the metal film and the metal of the substrate surface may be the same metal or may be different metals. The dielectric surface may be formed of any suitable dielectric material. In some embodiments, the dielectric material comprises nitrogen or oxygen atoms. Without being limited by theory, it is believed that these materials react with the alkyl halide and prevent the halogen from adsorbing onto the substrate surface in order to catalyze the reaction with the metal precursor. As a result, little, if any, metal film is formed on the dielectric surface.

[0159] In some embodiments, the deposition temperature is below the decomposition temperature of the alkyl halide. Again, without being bound by theory, it is believed that if the alkyl halide decomposes, the halogen will be available to react with the metal precursor on all surfaces (regardless of composition), which results in the deposition of metal films on all substrate surfaces (including dielectric surfaces). In some embodiments, the deposition temperature is at or above the decomposition temperature of the alkyl halide.

[0160] Some embodiments of the present disclosure advantageously provide methods for controlling the deposition of metal films. In some embodiments, the deposition rate is controlled. In some embodiments, the deposition location is controlled.

[0161] The methods of various embodiments use atomic layer deposition (ALD) or chemical vapor deposition (CVD) to form a metal film. Figure 7 An exemplary ALD process and Figure 8 An exemplary CVD process of FIG.

[0162] As mentioned earlier, Figure 7 and Figure 8 The general deposition process shown is performed as a thermal process without the use of plasma reactants. The use and effects of plasma and other additional reactants are discussed further below.

[0163] Some embodiments of the present disclosure advantageously provide methods of depositing metal films within substrate features or other structures.Exemplary features or structures include, but are not limited to, trenches or vias.

[0164] Some embodiments of the present disclosure advantageously provide a deposition control method for reducing film deposition outside of a target feature and near a feature opening. Without being limited by theory, it is believed that reducing deposition in these areas allows for faster gap filling within the target feature and reduces blocking near the feature opening and the formation of voids or seams within the feature.

[0165] See also Figure 7 and Figure 8 Without limiting the scope of the above disclosure, the ALD and CVD processes described above utilize alkyl halides and metal precursors to deposit metal films. Without being bound by theory, it is believed that the alkyl halides act as catalysts when depositing metal films. Thus, as demonstrated in particular by the CVD process, a single exposure of the substrate surface to the alkyl halide can be used to deposit metal films having a thickness greater than 10 nm.

[0166] Some embodiments of the present disclosure advantageously provide a deposition control method for reducing catalyst activity in a predetermined region of a substrate surface. In some embodiments, the activity of the catalyst is reduced. In some embodiments, the activity of the catalyst is eliminated.

[0167] See also FIG. 10A to FIG. 10D , an exemplary substrate 400 is shown during processing according to one or more embodiments of the present disclosure. FIG. 10A to FIG. 10D The illustrated substrate 1000 is simplified for illustration purposes. Fig. 9 As shown, in some embodiments, the substrate of the present disclosure contains FIG. 10A to FIG. 10D The features or structures depicted in.

[0168] exist Fig. 10A In the embodiment, substrate 1000 includes substrate surface 1010. Fig. 10B In the process, the substrate surface 1010 is exposed to an alkyl halide to form an activated surface 1020. As described above, the alkyl halide 1040 is adsorbed to the substrate surface 1010 to form the activated substrate surface 1020.

[0169] exist Fig. 10C In the process, a predetermined area of ​​the activated surface 1020 is exposed to a deactivation process to form a deactivated surface 1030 . Fig. 10B and Fig. 10C The alkyl halide 1040 is shown as a circle or an oval, however, it is not intended to convey a specific molecular shape. Fig. 10B and Fig. 10C The circular shape shown is similar to Fig. 10C The differences between the oval shapes shown are intended only to convey the activity and / or relative concentration of the alkyl halide on the substrate surface.

[0170] exist Fig. 10D In the process, the substrate 1000 is exposed to a metal precursor to form a metal film 1050. Fig. 10D As shown, the thickness T1 of the metal film 1050 on the activated surface 1020 is greater than the thickness T2 of the metal film 1050 on the deactivated surface 1030 .

[0171] In some embodiments, the deactivation process reduces the concentration of the alkyl halide on the activated surface 1020. In some embodiments, the deactivation process reduces the catalytic activity of the alkyl halide on the activated surface 1020.

[0172] In some embodiments, the above FIG. 10A to FIG. 10DThe described method is modified to include a deactivation process prior to exposure to the alkyl halide. In this regard, the deactivation process can be understood as "super-activating" a predetermined area of ​​the substrate surface 1010 prior to exposure to the alkyl halide. After exposure to the alkyl halide, the "super-activated" surface forms a higher concentration or activity of alkyl halide compared to the surface not exposed to the deactivation process. The difference in concentration and / or activity between the surfaces can be used to control deposition. In some embodiments, the surface can be as described above with respect to FIG. 10C to FIG. 10D Further deactivation is described.

[0173] Thickness T1 is greater than thickness T2. Thus, some embodiments of the present disclosure advantageously provide a deposition control method for controlling the amount of deposition in a predetermined area of ​​a substrate surface.

[0174] In some embodiments, the ratio of T1:T2 is greater than or equal to about 1:1, greater than or equal to about 2:1, greater than or equal to about 3:1, greater than or equal to about 4:1, greater than or equal to about 5:1, or greater than or equal to about 10:1. In some embodiments, little to no metal deposition occurs on the deactivated surface 1030. In other words, in some embodiments, the thickness T2 is about 0. In other words, there is substantially no amount of metal film 1050 deposited on the deactivated surface 1030. As used in this regard, "substantially no" means that the metal film on the deactivated surface covers less than 5%, less than 2%, less than 1%, or less than 0.5% of the deactivated surface.

[0175] The thickness of the metal film 1050 deposited on the activated surface 1020 and the deactivated surface 1030 is directly proportional to the deposition rate on the activated surface 1020 and the deactivated surface 1030. Thus, some embodiments of the present disclosure advantageously provide a deposition control method for controlling the deposition rate in a predetermined area of ​​a substrate surface.

[0176] In some embodiments, the entire substrate surface is exposed to the deactivation process. Some embodiments of the present disclosure may be used to control the amount of deposition across the substrate. Some embodiments of the present disclosure may be used to control the deposition rate across the substrate.

[0177] In some embodiments not shown, substrate 1000 includes one or more features. In some embodiments, deactivated surface 1030 is a surface outside of one or more features. In some embodiments, deactivated surface 1030 is a surface near the top of a sidewall of one or more features.

[0178] Without being limited by theory, it is believed that due to multiple exposed surfaces in close proximity to each other, the surfaces near the substrate features and the top surfaces of the sidewalls of those features are more highly activated (showing greater deposition). The greater deposition on these surfaces increases the likelihood that the features will be close before a sufficient amount of film is formed inside the features. When features are closed, seams or gaps are often formed. Thus, in some embodiments, the deactivated surface 1030 is a surface near the top of one or more features. In addition, in some embodiments, the deactivated surface 1030 is a surface near the substrate features. In some embodiments, the metal film deposited in the feature has reduced seams or gaps. In some embodiments, the metal film deposited in the feature has substantially no seams or gaps. As used in this regard, the term "substantially no seams" means that any gap formed in the film between the sidewalls is less than about 1% of the cross-sectional area of ​​the sidewalls.

[0179] In some embodiments, a predetermined area of ​​the substrate is exposed to hydrogen gas without using a plasma.

[0180] In some embodiments, a pulse of hydrogen is introduced into the ALD deposition cycle described above. In other words, the substrate may be exposed to a pulse sequence of alkyl halide, purge, hydrogen, purge, metal precursor, purge. In some embodiments, after exposure to the metal precursor, the substrate is exposed to an additional pulse of hydrogen followed by a purge. In some embodiments, after exposure to the alkyl halide, the substrate is exposed to an additional pulse of hydrogen followed by a purge. In some embodiments, a purge stage between each exposure to the metal precursor and / or alkyl halide is performed in some but not all cycles.

[0181] In some embodiments, hydrogen exposure is introduced into the CVD deposition cycle described above. In other words, the substrate can be impregnated with an alkyl halide, exposed to hydrogen, and exposed to a metal precursor. In some embodiments, the substrate is exposed to hydrogen prior to exposure to the metal precursor. In some embodiments, hydrogen and the metal precursor flow simultaneously.

[0182] In some embodiments, a predetermined area of ​​the substrate is exposed to a plasma comprising one or more of hydrogen (H2), ammonia (NH3), or argon (Ar). In some embodiments, the plasma used to deactivate the surface is a low-power plasma. In some embodiments, the plasma has a power in a range of about 50 W to about 500 W, in a range of about 50 W to about 300 W, in a range of about 50 W to about 200 W, or in a range of about 50 W to about 100 W.

[0183] In some embodiments, the plasma exposure time is less than or equal to about 30 seconds, less than or equal to about 20 seconds, less than or equal to about 15 seconds, less than or equal to about 10 seconds, less than or equal to about 5 seconds, or less than or equal to about 2 seconds.

[0184] In some embodiments, the plasma is a conductively coupled plasma (CCP). In some embodiments, the plasma is an inductively coupled plasma (ICP). In some embodiments, the plasma is a direct plasma generated in the processing environment. In some embodiments, the plasma is a remote plasma generated outside the processing environment.

[0185] In some embodiments, a plasma pulse is introduced into the ALD deposition cycle described above. In some embodiments, a plasma pulse replaces the hydrogen pulse described above with respect to the ALD deposition cycle.

[0186] In some embodiments, a plasma pulse is introduced into the CVD deposition cycle described above. In some embodiments, a plasma pulse replaces the hydrogen exposure described above with respect to the CVD deposition cycle.

[0187] References throughout this specification 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 the embodiment is included in at least one embodiment of the present disclosure. Thus, the appearance of phrases such as "in one or more embodiments," "in certain embodiments," "in an embodiment," or "in an embodiment" in various places throughout this specification do not necessarily refer to the same embodiment of the present disclosure. Furthermore, particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments.

[0188] Although the disclosure herein has been described with reference to specific embodiments, it will be understood that such embodiments are merely illustrative of the principles and applications of the disclosure. Those skilled in the art will appreciate 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, the disclosure is intended to include modifications and variations within the scope of the appended claims and their equivalents.

Claims

1. A metal deposition method comprising the following steps: immersing the substrate in an alkyl halide to form an activated substrate surface; and The substrate is exposed to a ruthenium precursor while the substrate is maintained at a deposition temperature to form a ruthenium film, the ruthenium precursor having a decomposition temperature higher than the deposition temperature, the alkyl halide comprising carbon and a halogen, and the halogen comprising bromine or iodine, wherein the method is performed without using an oxygen-containing reactive gas.

2. The method of claim 1, wherein the substrate has a substrate surface having at least one feature formed therein, the at least one feature having sidewalls and a bottom. 3 . The method of claim 2 , wherein a surface of a dielectric material forms the sidewalls, and a surface of a metal material forms the bottom.

4. The method of claim 2, further comprising the step of depositing a metal nitride liner in the at least one feature.

5. The method of claim 1, further comprising the step of depositing a seed layer on the surface of the substrate prior to immersing the substrate.

6. The method of claim 1, wherein the alkyl halide comprises greater than 95% ethyl iodide or diiodomethane on a molar basis.

7. The method of claim 1, wherein the ruthenium precursor comprises a ruthenium atom bonded to an optionally alkyl-substituted benzene ring and an open or closed diene.

8. The method of claim 1, wherein the substrate is immersed for a period in the range of 3 seconds to 60 seconds.

9. The method of claim 1, wherein the substrate is exposed to the ruthenium precursor for a period greater than or equal to 60 seconds.

10. The method of claim 1, wherein the alkyl halide comprises ethyl iodide and the deposition temperature is about 225°C.

11. The method of claim 1, wherein the halogen is insoluble in the ruthenium film.

12. A method for selectively depositing a ruthenium film on a metal surface, the method comprising the following steps: immersing a substrate including a dielectric surface and a metal surface in an alkyl halide to form an activated substrate surface; and The substrate is exposed to a ruthenium precursor to form a ruthenium film while the substrate is maintained at a deposition temperature, the ruthenium precursor having a decomposition temperature higher than the deposition temperature, the alkyl halide comprising carbon and a halogen, and the halogen comprising bromine or iodine, the deposition temperature being less than the decomposition temperatures of the alkyl halide and the ruthenium precursor.

13. The method of claim 12, wherein the metal surface is selected from ruthenium or tungsten.

14. The method of claim 12, wherein the ruthenium precursor comprises a ruthenium atom bonded to an optionally alkyl-substituted benzene ring and an open or closed diene.

15. The method of claim 12, wherein the halogen is insoluble in the metal film.

16. The method of claim 12, wherein the alkyl halide comprises greater than 95% ethyl iodide on a molar basis.

17. The method of claim 12, wherein the substrate is immersed for a period in the range of 3 seconds to 60 seconds.

18. The method of claim 12, wherein the substrate is exposed to the ruthenium precursor for a period greater than or equal to 60 seconds.

19. A method for selectively depositing a ruthenium film on a dielectric surface, the method comprising the steps of: exposing a substrate including a dielectric surface and a metal surface to a blocking compound to block the metal surface, the blocking compound having a general formula R'≡R", wherein R' and R" are alkyl or other carbon-containing groups; immersing the substrate in an alkyl halide to form an activated substrate surface; and The substrate is exposed to a ruthenium precursor to form a ruthenium film while the substrate is maintained at a deposition temperature, wherein the ruthenium precursor has a decomposition temperature higher than the deposition temperature, the alkyl halide comprises carbon and a halogen, and the halogen comprises bromine or iodine, and the deposition temperature is between the decomposition temperatures of the alkyl halide and the ruthenium precursor.

20. The method of claim 19, wherein the blocking compound comprises 3-hexyne.

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