Metal-doped carbon hardmasks

Abstract

Exemplary deposition methods may include transferring a ruthenium-containing precursor and a hydrogen-containing precursor to a processing area of ​​a semiconductor processing chamber. At least one of the ruthenium-containing precursor or the hydrogen-containing precursor may include carbon. The methods may include forming a plasma of all precursors within the processing area of ​​the semiconductor processing chamber. The methods may include depositing ruthenium and carbon materials on a substrate disposed within the processing area of ​​the semiconductor processing chamber.

Description

Technology Field

[0001] This application claims the benefit and priority of U.S. Patent Application No. 17 / 330,035, filed on May 25, 2021, with the title of the invention “METAL-DOPED CARBON HARDMASKS”, which is incorporated herein by reference in its entirety.

[0002] The present technology relates to semiconductor deposition processes. More specifically, the present technology relates to methods for depositing materials incorporating transition metals. Background Technology

[0003] Integrated circuits have been made possible by processes that create complexly patterned material layers on substrate surfaces. Creating patterned materials on a substrate requires controlled methods for the formation and removal of exposed materials. Stacked memory, such as vertical or 3D NAND, may involve the formation of a series of alternating layers of dielectric materials through which multiple memory holes or apertures can be etched. Mask materials used during memory hole formation may be retained during etching through tens or hundreds of layers of material. Material selectivity, as well as hard mask material thicknesses and surface roughness, can lead to inconsistent patterning, which can further affect the uniformity or consistency of the formed structures.

[0004] Therefore, there is a need for improved systems and methods that can be used to produce high-quality devices and structures. These and other needs are addressed by the present technology.

[0005] Exemplary deposition methods may include the step of transferring a ruthenium-containing precursor and a hydrogen-containing precursor to a processing area of ​​a semiconductor processing chamber. At least one of the ruthenium-containing precursor or the hydrogen-containing precursor may contain carbon. The methods may include the step of forming a plasma of all precursors within the processing area of ​​the semiconductor processing chamber. The methods may include the step of depositing ruthenium and carbon materials on a substrate disposed within the processing area of ​​the semiconductor processing chamber.

[0006] In some embodiments, the ruthenium and carbon materials may be characterized by an as-deposited surface roughness of about 2 nm or less. The ruthenium and carbon materials may be characterized by a ruthenium concentration of about 5 at.% or more. The ruthenium and carbon materials may be characterized by a grain size of about 50 Å or less. During the deposition of the ruthenium and carbon materials on the substrate, the temperature of the substrate may be maintained at about 300 °C or higher. During the deposition of the ruthenium and carbon materials on the substrate, the pressure may be maintained at about 15 Torr or lower. During the deposition of the ruthenium and carbon materials on the substrate, the low-frequency plasma power may be maintained at about 100 W or higher. The methods may include a step of ramping one or more of the chamber pressure or plasma power during the deposition of the ruthenium and carbon materials on the substrate. The methods may include a step of providing an argon precursor together with a ruthenium-containing precursor and a hydrogen-containing precursor. The methods may include the step of providing a boron-containing precursor or a nitrogen-containing precursor together with a ruthenium-containing precursor and a hydrogen-containing precursor. The methods may include the step of removing ruthenium and carbon materials using ozone. The step of removing ruthenium and carbon materials may be performed at a substrate temperature of about 300°C or lower.

[0007] Some embodiments of the present technology may include deposition methods. The methods may include the step of transferring a transition metal-containing precursor and a hydrogen-containing precursor to a processing area of ​​a semiconductor processing chamber. At least one of the transition metal-containing precursor or the hydrogen-containing precursor may include carbon. The methods may include the step of forming a plasma of all precursors within the processing area of ​​the semiconductor processing chamber. The methods may include the step of depositing transition metal and carbon materials on a substrate disposed within the processing area of ​​the semiconductor processing chamber.

[0008] In some embodiments, the transition metal may be ruthenium or osmium, or may include these. The transition metal and carbon material may be characterized by a ruthenium or osmium concentration of about 5 at.% or more. The methods may include a step of ashing the transition metal and carbon material from the substrate. The ashing step may be performed using ozone or plasma-enhanced oxygen. The step of ashing the transition metal and carbon material may be performed at a substrate temperature of about 300 °C or less. The methods may include a step of ramping one or more of chamber pressure or plasma power while depositing the transition metal and carbon material on the substrate. While depositing the transition metal and carbon material on the substrate, the low-frequency plasma power may be maintained at about 100 W or more. The transition metal-containing precursor may be an organometallic precursor or a metal-halide precursor, or may include these.

[0009] Some embodiments of the present technology may encompass deposition methods. The methods may include the step of transferring a transition metal-containing precursor and a hydrogen-containing precursor to a processing area of ​​a semiconductor processing chamber. At least one of the transition metal-containing precursor or the hydrogen-containing precursor may contain carbon. The methods may include the step of forming a plasma of all precursors within the processing area of ​​the semiconductor processing chamber. The methods may include the step of depositing transition metal and carbon materials on a substrate disposed within the processing area of ​​the semiconductor processing chamber. The transition metal and carbon materials may be characterized by a transition metal concentration of about 5 at.% or more. The methods may include the step of ashing the transition metal and carbon materials from the substrate. The ashing step may be performed using ozone or plasma-enhanced oxygen.

[0010] Such technology can provide numerous advantages over conventional systems and techniques. For example, processes can produce metal-containing films characterized by reduced surface roughness. Additionally, operations of embodiments of the present technology can produce improved mask materials that can facilitate processing operations. These and other embodiments, along with many of their advantages and features, are described in more detail in conjunction with the following description and the accompanying drawings. Brief explanation of the drawing

[0011] Further understanding of the nature and advantages of the disclosed technology can be realized by reference to the drawings and the remainder of this specification.

[0012] FIG. 1 illustrates a schematic cross-sectional view of an exemplary processing chamber according to some embodiments of the present technology.

[0013] FIG. 2 illustrates exemplary operations in a deposition method according to some embodiments of the present technology.

[0014] Some of the drawings are included as schematics. It should be understood that the drawings are for illustrative purposes only and should not be considered to be of actual scale unless specifically stated otherwise. Additionally, as schematics, the drawings are provided for illustrative purposes and may not include all modes or information compared to realistic representations, and may include exaggerated materials for illustrative purposes.

[0015] In the attached drawings, similar components and / or features may have the same reference label. Additionally, various components of the same type may be distinguished by a character following the reference label that distinguishes between similar components. Where only the first reference label is used in this specification, the description is applicable to any component among similar components having the same first reference label, regardless of the character. Specific details for implementing the invention

[0016] In the transition from 2D NAND to 3D NAND, many process operations are modified from vertical to horizontal. Additionally, as the number of cells forming 3D NAND structures increases, the aspect ratios of memory holes and other structures increase, sometimes rapidly. During 3D NAND processing, stacks of placeholder layers and dielectric materials can form inter-electrode dielectric layers. These placeholder layers may undergo various operations to place structures before the material is completely removed and replaced with metal. Some processes, particularly memory hole formation or staircase formation, may involve etching through most or all layers of the stack. Mask materials can be used to allow materials to be partially etched or to be etched to create features across the entire substrate. Utilizing masks to etch tens or hundreds of layers can be difficult with current mask technology.

[0017] Many conventional techniques utilize etching processes to create memory and logic structures that may not be properly executed on future process nodes. For example, as the number of cells within a structure increases to hundreds, memory holes can be formed to depths of several micrometers. For instance, masks used to define memory holes may struggle to maintain selectivity for deeper etchings. For instance, as the number of layer pairs increases, the thickness of conventional masks may increase, for instance, to more than several micrometers. However, increased mask thickness can place a burden on etching processes that require performing opening operations through the mask and preserving features when the underlying structure is etched. Consequently, conventional mask techniques may not be effective on future process nodes.

[0018] The transition to different mask materials can present a new set of challenges. For example, metal-containing mask layers can increase film hardness or other mechanical properties and etch selectivity, but they can also cause processing issues. For instance, hard mask opening processes may become more difficult to etch selectively. Additionally, metal incorporation can limit removal operations. For instance, carbon hard masks can be easily removed in an oxygen plasma, which allows for relatively easy stripping after processing through the mask is complete. Metals, typically, are non-volatile when contacted by an oxygen plasma, which may require more aggressive removal. For instance, wet etching or chemical mechanical polishing may be utilized to remove metal hard masks. Consequently, overall processing can become more difficult with these mask materials, and throughput may be adversely affected by newer materials. Furthermore, metal-containing hard masks may not provide sufficient film properties to process distinct features on a substrate. For example, carbon hard masks can be substantially amorphous, and small features, such as memory holes in 3D NAND, can be formed through the mask with high uniformity. Metal-containing mask materials may have increased roughness due to grain formation, which can cause shifting and roughness at the mask opening and transfer to the substrate during the etching process, potentially causing yield issues or losses.

[0019] The present technology can overcome these limitations by producing metal-containing hard masks that can be characterized by lower film roughness and grain size. Advantageously, hard masks according to some embodiments of the present technology can also be easily peeled off in ashing processes using an oxygen-containing removal process. For example, hard masks can be removed using ozone or oxygen-containing plasma after processing is complete. This can promote improved selectivity compared to carbon or silicon hard masks while having a limited impact on throughput. After describing general aspects of chambers according to embodiments of the present technology in which the plasma processing operations discussed below can be performed, specific methodologies and component configurations may be discussed. It should be understood that the present technology is not intended to be limited to the specific films and processing operations discussed, as the described techniques can be used to improve a number of film formation processes and can be applied to various processing chambers and operations.

[0020] FIG. 1 illustrates a cross-sectional view of an exemplary processing chamber (100) according to some embodiments of the present invention. The drawing may illustrate an overview of a system that may be specifically configured to incorporate one or more aspects of the present invention and / or perform one or more operations according to embodiments of the present invention. Further details of the chamber (100) or the methods performed may be further described below. It should be understood that while the chamber (100) may be utilized to form film layers according to some embodiments of the present invention, the methods may similarly be performed in any chamber where film formation may occur. The processing chamber (100) may include a chamber body (102), a substrate support (104) disposed inside the chamber body (102), and a cover assembly (106) coupled to the chamber body (102) and surrounding the substrate support (104) in a processing volume (120). For processing, a substrate (103) may be provided to a processing volume (120) through an opening (126) that can be traditionally sealed using a slit valve or door. The substrate (103) may be placed on the surface (105) of a substrate support during processing. The substrate support (104) may be rotatable along an axis (147) to which the shaft (144) of the substrate support (104) can be located, as indicated by the arrow (145). Alternatively, the substrate support (104) may be lifted to rotate as needed during the deposition process.

[0021] A plasma profile modulator (111) may be placed within a processing chamber (100) to control the plasma distribution across the entire substrate (103) placed on a substrate support (104). The plasma profile modulator (111) may include a first electrode (108) that may be placed adjacent to the chamber body (102) and may separate the chamber body (102) from other components of the cover assembly (106). The first electrode (108) may be part of the cover assembly (106) or may be a separate sidewall electrode. The first electrode (108) may be an annular or ring-shaped member and may be a ring electrode. The first electrode (108) may be a continuous loop around the circumference of the processing chamber (100) surrounding the processing volume (120) or may be discontinuous at selected locations if desired. The first electrode (108) may also be a perforated electrode, such as a perforated ring or mesh electrode, or a plate electrode such as a secondary gas distributor, for example.

[0022] One or more insulators (110a, 110b), which may be dielectric materials such as ceramic or metal oxide, e.g., aluminum oxide and / or aluminum nitride, may come into contact with the first electrode (108) and may electrically and thermally isolate the first electrode (108) from the gas distributor (112) and from the chamber body (102). The gas distributor (112) may define apertures (118) for dispensing process precursors into the processing volume (120). The gas distributor (112) may be coupled to a first power source (142), e.g., an RF generator, an RF power source, a DC power source, a pulsed DC power source, a pulsed RF power source, or any other power source that may be coupled to the processing chamber. In some embodiments, the first power source (142) may be an RF power source.

[0023] The gas distributor (112) may be a conductive gas distributor or a non-conductive gas distributor. The gas distributor (112) may also be formed of conductive and non-conductive components. For example, the body of the gas distributor (112) may be conductive, while the face plate of the gas distributor (112) may be non-conductive. The gas distributor (112) may be powered by a first power source (142), for example as shown in FIG. 1, or the gas distributor (112) may be coupled to ground in some embodiments.

[0024] The first electrode (108) may be coupled to a first tuning circuit (128) capable of controlling the ground path of the processing chamber (100). The first tuning circuit (128) may include a first electronic sensor (130) and a first electronic controller (134). The first electronic controller (134) may be a variable capacitor or other circuit elements, or may include them. The first tuning circuit (128) may be one or more inductors (132) or may include them. The first tuning circuit (128) may be any circuit that enables a variable or controllable impedance under plasma conditions present in the processing volume (120) during processing. In some embodiments as illustrated, the first tuning circuit (128) may include a first circuit leg and a second circuit leg coupled in parallel between ground and the first electronic sensor (130). The first circuit leg may include a first inductor (132A). The second circuit leg may include a second inductor (132B) coupled in series with the first electronic controller (134). The second inductor (132B) may be positioned between the first electronic controller (134) and a node connecting both the first and second circuit legs to the first electronic sensor (130). The first electronic sensor (130) may be a voltage or current sensor and may be coupled to the first electronic controller (134), which can provide a certain degree of closed-loop control of plasma conditions within the processing volume (120).

[0025] The second electrode (122) may be coupled to the substrate support (104). The second electrode (122) may be embedded within the substrate support (104) or coupled to the surface of the substrate support (104). The second electrode (122) may be a plate, a perforated plate, a mesh, a wire screen, or any other distributed array of conductive elements. The second electrode (122) may be a tuning electrode and may be coupled to a second tuning circuit (136) by a cable having a selected resistance, e.g., 50 ohms, which is placed in a conduit (146), e.g., the shaft (144) of the substrate support (104). The second tuning circuit (136) may include a second electronic sensor (138) and a second electronic controller (140), which may be a second variable capacitor. The second electronic sensor (138) may be a voltage or current sensor and may be coupled with the second electronic controller (140) to provide additional control over the plasma conditions of the processing volume (120).

[0026] A third electrode (124), which may be a bias electrode and / or an electrostatic chucking electrode, may be coupled to a substrate support (104). The third electrode may be coupled to a second power source (150) through a filter (148), which may be an impedance matching circuit. The second power source (150) may be DC power, pulsed DC power, RF bias power, pulsed RF source or bias power, or a combination of these or other power sources. In some embodiments, the second power source (150) may be RF bias power.

[0027] The cover assembly (106) and substrate support (104) of FIG. 1 may be used with any processing chamber for plasma or thermal processing. In operation, the processing chamber (100) may provide real-time control of plasma conditions within the processing volume (120). A substrate (103) may be placed on the substrate support (104), and process gases may flow through the cover assembly (106) using the inlet (114) according to any desired flow plan. The gases may exit the processing chamber (100) through the outlet (152). Power may be coupled to the gas distributor (112) to establish plasma in the processing volume (120). In some embodiments, the substrate may be electrically biased using a third electrode (124).

[0028] When plasma is energized in the processing volume (120), a potential difference can be established between the plasma and the first electrode (108). A potential difference can also be established between the plasma and the second electrode (122). Then, electronic controllers (134, 140) can be used to adjust the flow properties of the ground paths represented by two tuning circuits (128 and 136). To provide independent control of the deposition rate and plasma density uniformity from the center to the edge, a set point can be transmitted to the first tuning circuit (128) and the second tuning circuit (136). In embodiments where both electronic controllers may be variable capacitors, electronic sensors can independently adjust the variable capacitors to maximize the deposition rate and minimize thickness non-uniformity.

[0029] Each of the tuning circuits (128, 136) may have a variable impedance that can be adjusted using individual electronic controllers (134, 140). If the electronic controllers (134, 140) are variable capacitors, the capacitance range of each variable capacitor, and the inductances of the first inductor (132A) and the second inductor (132B) may be selected to provide an impedance range. This range may depend on the frequency and voltage characteristics of the plasma, and the range may have a minimum value in the capacitance range of each variable capacitor. Therefore, when the capacitance of the first electronic controller (134) is at a minimum or maximum value, the impedance of the first tuning circuit (128) may be high, and as a result, may result in a plasma shape having minimal aerial or lateral coverage over the substrate support. When the capacitance of the first electronic controller (134) approaches a value that minimizes the impedance of the first tuning circuit (128), the air coverage of the plasma increases to a maximum value, so that the entire operating area of ​​the substrate support (104) can be effectively covered. When the capacitance of the first electronic controller (134) deviates from the minimum impedance setting, the plasma shape may contract from the chamber walls and the air coverage of the substrate support may be reduced. The second electronic controller (140) can have a similar effect, so that when the capacitance of the second electronic controller (140) changes, the air coverage of the plasma over the substrate support can be increased and decreased.

[0030] Electronic sensors (130, 138) can be used to tune individual circuits (128, 136) in a closed loop. Depending on the type of sensor used, a set point for current or voltage may be installed on each sensor, and the sensor may be provided with control software that determines the adjustment for each individual electronic controller (134, 140) to minimize deviation from the set point. Consequently, the plasma shape can be selected and dynamically controlled during processing. Although the foregoing discussion is based on electronic controllers (134, 140) which may be variable capacitors, it should be understood that any electronic component having adjustable characteristics may be used to provide tuning circuits (128 and 136) having adjustable impedance.

[0031] FIG. 2 illustrates exemplary operations in a deposition method (200) according to some embodiments of the present invention. The method may be performed in various processing chambers including the processing chamber (100) described above. The method (200) may include a number of optional operations that may or may not be specifically associated with some embodiments of methods according to the present invention. For example, while many of the operations are described to provide a wider range of structure formations, they may be performed by alternative methodologies that are not critical to the present invention or are readily recognizable.

[0032] The method (200) may include additional operations prior to the initiation of the listed operations. For example, additional processing operations may include forming structures including stacks of materials for 3D NAND on a semiconductor substrate, forming transistors or other memory structures, or any other processing that may include both forming and removing materials. Pre-processing operations may be performed in a chamber where the method (200) may be performed, or processing may be performed in one or more other processing chambers before the substrate is transferred into the semiconductor processing chamber where the method (200) may be performed. Nevertheless, the method (200) may optionally include the step of transferring a semiconductor substrate to a processing area of ​​a semiconductor processing chamber, e.g., the processing chamber (100) described above, or other chambers that may include components as described above. The substrate may be a pedestal such as a substrate support (104) and may be deposited on a substrate support that may exist in a processing area of ​​the chamber, e.g., the processing volume (120) described above.

[0033] The substrate may be any number of materials upon which materials can be deposited, or may comprise any number of such materials. The substrate may be any number of combinations of these materials, including dielectric materials comprising silicon, germanium, silicon oxide, or silicon nitride, metallic materials, or substrates, or materials formed on the substrate. In some embodiments, optional processing operations, such as pretreatment, may be performed to prepare the surface of the substrate for deposition. For example, pretreatment may be performed to provide specific ligand terminations on the surface of the substrate, and pretreatment may promote the nucleation of the film to be deposited. For example, other molecular terminations comprising hydrogen, oxygen, carbon, nitrogen, or any combination of these atoms or radicals may be adsorbed, reacted, or formed on the surface of the substrate. Additionally, any other operation capable of removing material, such as reducing native oxides or etching the material, or preparing one or more exposed surfaces of the substrate for deposition may be performed.

[0034] In operation (205), one or more precursors may be delivered to the processing area of ​​the chamber. For example, in exemplary embodiments where a transition-metal-incorporated carbon film may be formed, a transition metal-containing precursor may be delivered to the processing area of ​​the processing chamber. Plasma-enhanced deposition may be performed in some embodiments of the present invention, which can facilitate material reactions and deposition. As mentioned above, some embodiments of the present invention may encompass the formation or deposition of transition metal and carbon materials, the transition metal and carbon materials may, for example, feature increased surface roughness compared to, for instance, thermally generated or plasma-generated silicon and carbon films. By controlling the formation characteristics and precursors utilized in the processing, the present invention can produce metal-containing films characterized by reduced surface roughness and grain size, and simultaneously produce materials that can be more easily removed in subsequent processing.

[0035] Some embodiments of the present invention may include additionally providing a hydrogen-containing precursor in operation (210), the hydrogen-containing precursor may be provided together with a transition metal-containing precursor. In some embodiments, a carbon-containing precursor capable of forming a transition metal and carbon film may also be provided. The carbon-containing precursor may be a transition metal precursor, a hydrogen-containing precursor, or a distinct precursor utilized in embodiments of the present invention. All of the delivered precursors may be used to form a plasma within a processing area of ​​a semiconductor processing chamber in operation (215). In operation (220), the transition metal and carbon materials may be deposited on a substrate. One or more additional precursors, such as argon, helium, nitrogen, or other carrier or inert gases, may also be included, which can facilitate plasma formation and the development of film properties. According to some embodiments of the present invention, material roughness and grain formation may be controlled and limited by generating plasma effluents of precursors.

[0036] For example, incorporating metallic materials into the film can lead to more extensive grain formation instead of producing a more amorphous film. With the control of environmental and plasma parameters, film modification or profile etching can be performed simultaneously with material deposition by incorporating additional hydrogen and / or inert sources, such as argon or helium. For example, hydrogen or inert gas ions and / or neutral species can refine grain and surface formation while generating a more uniform profile through reactions and / or physical interactions with features being formed by transition metals and carbon materials. Consequently, the grains may not expand to a significant extent compared to conventional processes that attempt to incorporate metals. To provide sufficient radicals in the process, the hydrogen-containing precursor and / or inert gas or carrier gas may be included at a higher flow rate than the transition metal-containing precursor.

[0037] For example, thermally generated silicon or carbon may be characterized by a relatively low average roughness, e.g., about 0.5 nm or less. The film may also be characterized by a relatively low roughness range, e.g., the difference between the highest and lowest peaks of the formed film. For example, the roughness range may be about 1.5 nm or less, or about 1 nm or less. However, in the case of metal-containing films produced according to the prior art, for films of similar thickness, the average roughness may be about 3 nm or more, about 4 nm or more, about 5 nm or more, or greater, although the mentioned roughness may increase as the film thickness increases. Additionally, the roughness range of the produced metal-containing material may be about 10 nm or more, about 15 nm or more, or greater, depending again on the film thickness. Furthermore, the grain size within the film may be about 3 nm or more, about 4 nm or more, about 5 nm or more, or greater. During subsequent etching operations, these larger imbalances across the film can make etching operation uniformity difficult and may require additional operations, such as additional chemical mechanical polishing.

[0038] However, the present technology can reduce or significantly reduce both the average roughness and the roughness range of the generated transition metal and carbon films by performing substantially simultaneous etching using additional hydrogen-containing precursors and / or argon or other inert gases, and by performing one or more additional adjustments further described below. For example, by depositing transition metal-containing materials according to some embodiments of the present technology, the materials immediately after deposition may be characterized by an average roughness of about 5 nm or less, about 4 nm or less, about 3.5 nm or less, about 3.0 nm or less, about 2.5 nm or less, about 2.0 nm or less, about 1.5 nm or less, about 1.0 nm or less, about 0.9 nm or less, about 0.8 nm or less, about 0.7 nm or less, about 0.6 nm or less, about 0.5 nm or less, or less than the average roughness.

[0039] Additionally, in some embodiments, the roughness can be substantially controlled regardless of the film thickness. This allows for the prevention of additional chemical mechanical polishing operations, as the film immediately after deposition can be characterized by any of the exemplified average roughness ranges. Additionally, the roughness range across the entire film immediately after deposition can be about 10 nm or less, about 9 nm or less, about 8 nm or less, about 7 nm or less, about 6 nm or less, about 5 nm or less, about 4 nm or less, about 3 nm or less, about 2 nm or less, about 1 nm or less, or less. Similarly, a controlled etching process during growth can also promote a reduction in the grain size of the metal-containing material, and the grain size can be maintained at about 5 nm or less, about 4 nm or less, about 3 nm or less, about 2 nm or less, about 1 nm or less, about 9 Å or less, about 8 Å or less, about 7 Å or less, about 6 Å or less, or less. Consequently, improved materials can be produced that not only provide film and mask benefits compared to conventional materials and processes, but also potentially reduce manufacturing operations by limiting or reducing the number of polishing operations in the sequence.

[0040] Any number of precursors may be used in the present art with respect to transition metal-containing precursors, hydrogen-containing precursors, and carbon-containing precursors (if included). Any number of transition metals may be covered by the present art, including cobalt, chromium, hafnium, molybdenum, osmium, rhenium, ruthenium, tantalum, titanium, tungsten, zirconium, or any other metal or transition metal that may be provided as a deposition precursor. For example, transition metal precursors may be or may include organometallic precursors as well as transition metal halides. When organometallic precursors are used, for example, carbon-containing precursors may not be used. As one non-limiting example, the transition metal may be ruthenium or osmium or may include it. Exemplary precursors may be any other ruthenium or osmium precursors, including bis(cyclopentadienyl)ruthenium, bis(ethylcyclopentadienyl)ruthenium, triruthenium dodecacarbonyl, triosmium dodecacarbonyl, or halogen-containing precursors, as well as any other transition metal precursors or may include these.

[0041] Hydrogen-containing precursors may include not only diatomic hydrogen but also hydrogen-containing materials that may be, for example, carbon-containing precursors or may include them. Where they are included, carbon-containing precursors may be any hydrocarbon, or any material containing or composed of carbon and hydrogen, or may include them. In some embodiments, the carbon-containing precursor may feature one or more carbon-carbon double bonds and / or one or more carbon-carbon triple bonds. Thus, in some embodiments, the carbon-containing precursor may be an alkene or alkyne, such as acetylene, ethylene, propene, or any other carbon-containing material, or may include them. The precursor may include carbon and hydrogen-containing precursors that may include any amount of carbon and hydrogen bonds along with any other elemental bonds, but in some embodiments, the carbon-containing precursor may consist of carbon-to-carbon and carbon-to-hydrogen bonds.

[0042] The incorporation of transition metals and / or carbon can be tuned to increase or decrease the incorporation based on one or more deposition parameters further discussed below. In some embodiments, the transition metal can be incorporated at about 5 at.% or more, about 10 at.% or more, about 15 at.% or more, about 20 at.% or more, about 25 at.% or more, about 30 at.% or more, about 35 at.% or more, about 40 at.% or more, about 45 at.% or more, about 50 at.% or more, about 55 at.% or more, about 60 at.% or more, about 65 at.% or more, about 70 at.% or more, or higher, but as the transition metal incorporation increases, the surface roughness may increase, and the roughness characteristics may exceed the thresholds discussed above due to the formation of more columnar structures. Accordingly, in some embodiments, the transition metal may be incorporated at about 75 at.% or less, and may be maintained at about 70 at.% or less, about 65 at.% or less, about 60 at.% or less, about 55 at.% or less, about 50 at.% or less, or less, which may maintain most of the carbon concentration in some embodiments. Carbon and / or hydrogen may represent the remainder in any compositions containing the transition metal incorporation within the ranges mentioned above, together with amounts of nitrogen, oxygen, or other residual materials that may be incorporated in trace amounts.

[0043] One or more additional modes of deposition may also be tuned to improve the modes of deposition being performed. For example, plasma power may affect the degree of precursor dissociation, and embodiments may include both high-frequency RF and low-frequency RF applied to the electrodes. In some embodiments, an interfacial layer may be created to promote the adhesion of the materials formed. During plasma generation, initial power may be applied by a high-frequency RF source, for example, to a faceplate or a first electrode, which may subsequently ramp to or stepwise change to bulk deposition power. By utilizing lower generation power, a smaller amount of dissociation may occur, which may increase carbon incorporation in the film. At the substrate interface, this may also promote the formation of smaller grain sizes throughout the film being deposited. Accordingly, in some embodiments, the plasma can initially be generated at a high-frequency plasma power operating at, among other frequencies, for example, 13.56 MHz or 27 MHz, at a power of about 500 W or less, and can be generated at a power of about 400 W or less, about 300 W or less, about 200 W or less, or less.

[0044] Following the first time period, the power can be ramped to a higher power or varied stepwise, which can increase the deposition as well as the incorporation of transition metals. For example, the power can be varied stepwise or ramped to a power of about 500 W or more, about 600 W or more, about 700 W or more, about 800 W or more, about 900 W or more, about 1000 W or more, about 1100 W or more, about 1200 W or more, about 1300 W or more, about 1400 W or more, about 1500 W or more, or varied stepwise or ramped to a higher power.

[0045] Low-frequency RF power may also be applied, for example, to a substrate, pedestal, or second electrode, and may be applied at about 1000 kHz or less, about 750 kHz or less, about 500 kHz or less, about 450 kHz or less, about 400 kHz or less, about 350 kHz or less, about 300 kHz or less, about 250 kHz or less, about 200 kHz or less, or at levels lower than that, including up to zero where the low-frequency power may not be used. The low-frequency RF supply can increase ion energy and increase physical impact on the film being formed, which can promote a reduction in grain size as discussed above. Additionally, the power can provide lower film stress. For example, while carbon hard masks may feature a more neutral film, metal-containing materials may feature more tensile stress, which can cause stress on the underlying structure, particularly on the subsequent mask patterning. By increasing the low-frequency RF power, the stress is reduced, which can produce a film featuring more neutral stress, similar to carbon hard masks. Thus, in some embodiments, the low-frequency power may be applied at about 100 W or more, about 150 W or more, about 200 W or more, about 250 W or more, about 300 W or more, about 350 W or more, about 400 W or more, about 450 W or more, about 500 W or more, or at higher power, but in some embodiments, the power may be maintained at about 500 W or less, which may cause the roughness to increase due to increased impact.

[0046] The temperatures of the substrate may additionally affect the deposition. For example, in some embodiments, the substrate may be maintained at a temperature of about 300°C or higher, about 320°C or higher, about 340°C or higher, about 360°C or higher, about 380°C or higher, about 400°C or higher, about 420°C or higher, about 440°C or higher, about 460°C or higher, about 480°C or higher, about 500°C or higher, or higher. Additionally, the pressure within the processing area may affect the amount of ionization and physical interaction performed during deposition. Lowering the processing pressure may result in lower ionization, which can increase the carbon concentration, for example, in the interface region. Increasing the processing pressure may result in increased ionization, which can promote transition metal incorporation and an increase in the deposition rate. Therefore, similar to plasma power, the pressure within the processing region can be adjusted from a first pressure during plasma generation to a second higher pressure after a first time period. Thus, in some embodiments, the processing pressure during generation can be maintained at about 6 Torr or less, about 5 Torr or less, about 4 Torr or less, about 3 Torr or less, about 2 Torr or less, or less. Subsequently, the pressure can be stepped or ramped, in some embodiments, to about 5 Torr or more, about 6 Torr or more, about 7 Torr or more, about 8 Torr or more, about 9 Torr or more, about 10 Torr or more, about 11 Torr or more, about 12 Torr or more, about 13 Torr or more, about 14 Torr or more, about 15 Torr or more, or higher pressure.

[0047] As previously mentioned, process conditions can be initially set to promote adhesion and grain control, and adjustments for bulk deposition can follow after the first time period. Since the interfacial layer may be limited to a few monolayers to promote adhesion, the first time period can be maintained for about 10 seconds or less, about 9 seconds or less, about 8 seconds or less, about 7 seconds or less, about 6 seconds or less, about 5 seconds or less, about 4 seconds or less, about 3 seconds or less, about 2 seconds or less, or less, followed by a transition to bulk deposition. As an additional action that can be performed during the first time period, a boron-containing precursor and / or a nitrogen-containing precursor may be included together with a transition metal precursor, which can increase adhesion and interfacial properties. The delivery of a boron-containing precursor or a nitrogen-containing precursor, which may include diborane or any other boron-containing precursor as well as diatomic nitrogen or any other nitrogen-containing precursor, may be discontinued after a first time period. By performing deposition according to embodiments of the present technology, reduced roughness of transition metal and carbon-containing films may be provided, which can improve hard mask efficiency.

[0048] Additionally, in some embodiments of the present technology, subsequent processing after mask removal may be performed by ashing. For example, after mask deposition, any number of patterning or etching operations utilizing the mask may be performed, as well as any number of operations including photolithography and mask opening. After processing is completed, the mask may be removed in an optional operation (225) or etched away. While conventional technologies may be forced to utilize more aggressive etching processes when metals are incorporated into films, the present technology may utilize transition metals that can be ashed in an oxygen-containing plasma or using ozone. In some embodiments, any number of wet or dry etchings utilizing plasma-enhanced halides may be used by utilizing transition metals capable of producing volatile oxygen-containing materials, for example, but the present technology may allow stripping or ashing similar to carbon hard masks.

[0049] In some embodiments as described above, the incorporated transition metal may be ruthenium or osmium, which can generate volatile complexes during oxygen-containing stripping operations. For example, operation (225) may involve contacting the transition metal and the carbon hard mask with an ozone or oxygen-containing plasma. In some embodiments, the removal operation may be limited to utilizing an ozone or oxygen-containing plasma. Ashing may remove the entire film and may not require subsequent dry or wet etching in some embodiments of the present technology. In some embodiments, removal may be performed at a removal temperature that can be controlled to limit harmful reactions, for example. In some embodiments, removal may be performed at a temperature of about 100°C or higher, about 120°C or higher, about 140°C or higher, about 160°C or higher, about 180°C or higher, about 200°C or higher, about 220°C or higher, about 240°C or higher, about 260°C or higher, about 280°C or higher, about 300°C or higher, or higher.

[0050] However, as the temperature increases, alternative oxide materials may be formed or additional phases of the metal may be formed, which may be characterized by reduced volatility and may limit or prevent removal by oxygen or other etchants. Accordingly, to ensure the formation of volatile oxides, in some embodiments, removal may be performed at a temperature of about 500°C or lower, about 450°C or lower, about 400°C or lower, about 380°C or lower, about 360°C or lower, about 340°C or lower, about 320°C or lower, about 300°C or lower, about 280°C or lower, or lower. Accordingly, by depositing and / or removing mask materials according to embodiments of the present technology, hard masks containing transition metals may be formed, which may be characterized by reduced roughness and stress while featuring improved removal and deposition compared to conventional technologies.

[0051] In the foregoing description, many details have been described for the purpose of explanation and to provide an understanding of various embodiments of the present technology. However, it will be apparent to those skilled in the art that certain embodiments may be practiced without some of these details or with additional details.

[0052] Although various embodiments have been disclosed, those skilled in the art will recognize that various modifications, alternative configurations, and equivalents may be used without departing from the spirit of the embodiments. Additionally, to avoid unnecessarily obscuring the art, many well-known processes and elements have not been described. Therefore, the above description should not be construed as limiting the scope of the art. Additionally, while methods or processes may be described sequentially or in steps, it should be understood that operations may be performed concurrently or in an order different from that listed.

[0053] Where a range of values ​​is given, each value existing between the upper and lower limits of such range is interpreted as also specifically stated up to one-tenth of the single-digit value of the smallest digit of the lower limit, unless otherwise clearly indicated in the context. Any narrower range between any mentioned values ​​or unmentioned intervening values ​​within the mentioned range and any other mentioned or intervening values ​​within the mentioned range is encompassed. The upper and lower limits of such sub-ranges may independently be included in or excluded from such ranges, and each range is also included in the description insofar as any specifically excluded limit is in the specified range, whether one or both of the upper and lower limits are included in such sub-ranges or both are excluded from such sub-ranges. Where a mentioned range includes one or both of the limits, ranges excluding either one or both of the included limits are also included.

[0054] As used herein and in the appended claims, singular forms include plural references unless the context clearly indicates otherwise. Thus, for example, a reference to "precursor" includes plural such precursors, and a reference to "layer" includes one or more layers and their equivalents known to those skilled in the art, etc.

[0055] Additionally, as used herein and in the following claims, the words “comprise,” “comprising,” “contain,” “containing,” “include,” and “including” are intended to specify the presence of the stated features, integers, components, or actions, but do not exclude the presence or addition of one or more other features, integers, components, actions, acts, or groups.

Claims

Claim 1 A deposition method comprising the steps of: transferring a ruthenium-containing precursor and a hydrogen-containing precursor to a processing area of ​​a semiconductor processing chamber — at least one of the ruthenium-containing precursor or the hydrogen-containing precursor comprises carbon —; forming a plasma of all precursors within the processing area of ​​the semiconductor processing chamber; and depositing ruthenium and carbon materials on a substrate disposed within the processing area of ​​the semiconductor processing chamber. Claim 2 A deposition method according to claim 1, wherein the ruthenium and carbon materials are characterized by an as-deposited surface roughness of about 2 nm or less. Claim 3 A deposition method according to claim 1, wherein the ruthenium and carbon materials are characterized by a ruthenium concentration of about 5 at.% or more. Claim 4 A deposition method according to claim 1, wherein the ruthenium and carbon materials are characterized by a grain size of about 50 Å or less. Claim 5 A deposition method according to claim 1, wherein the temperature of the substrate is maintained at about 300°C or higher during the step of depositing the ruthenium and carbon materials on the substrate. Claim 6 A deposition method according to claim 1, wherein the pressure is maintained at about 15 Torr or less during the step of depositing the ruthenium and carbon materials on the substrate. Claim 7 A deposition method according to claim 1, wherein during the step of depositing the ruthenium and carbon materials on the substrate, the low-frequency plasma power is maintained at about 100 W or more. Claim 8 A deposition method according to claim 1, further comprising the step of ramping one or more of chamber pressure or plasma power during the step of depositing the ruthenium and carbon materials on the substrate. Claim 9 A deposition method according to claim 1, further comprising the step of providing an argon precursor together with the ruthenium-containing precursor and the hydrogen-containing precursor. Claim 10 A deposition method according to claim 1, further comprising the step of providing a boron-containing precursor or a nitrogen-containing precursor together with the ruthenium-containing precursor and the hydrogen-containing precursor. Claim 11 A deposition method according to claim 1, further comprising the step of removing the ruthenium and carbon materials using ozone. Claim 12 A deposition method according to claim 11, wherein the step of removing the ruthenium and carbon materials is performed at a substrate temperature of about 300°C or lower. Claim 13 A deposition method comprising the steps of: transferring a transition metal-containing precursor and a hydrogen-containing precursor to a processing area of ​​a semiconductor processing chamber — at least one of the transition metal-containing precursor or the hydrogen-containing precursor comprises carbon —; forming a plasma of all precursors within the processing area of ​​the semiconductor processing chamber; and depositing a transition metal and a carbon material on a substrate disposed within the processing area of ​​the semiconductor processing chamber. Claim 14 A deposition method according to claim 13, wherein the transition metal comprises ruthenium or osmium, and the transition metal and carbon material are characterized by a ruthenium or osmium concentration of about 5 at.% or more. Claim 15 A deposition method according to claim 13, further comprising the step of ashing the transition metal and carbon material from the substrate, wherein the ashing is performed using ozone or plasma-enhanced oxygen. Claim 16 A deposition method according to claim 15, wherein the step of ashing the transition metal and carbon materials is performed at a substrate temperature of about 300°C or lower. Claim 17 A deposition method according to claim 13, further comprising the step of ramping one or more of chamber pressure or plasma power while depositing the transition metal and carbon materials on the substrate. Claim 18 A deposition method according to claim 13, wherein the low-frequency plasma power is maintained at about 100 W or more while depositing the transition metal and carbon materials on the substrate. Claim 19 In claim 13, the deposition method wherein the transition metal-containing precursor comprises an organometallic precursor or a metal halide precursor. Claim 20 A deposition method comprising: transferring a transition metal-containing precursor and a hydrogen-containing precursor to a processing area of ​​a semiconductor processing chamber — at least one of the transition metal-containing precursor or the hydrogen-containing precursor comprises carbon —; forming a plasma of all precursors within the processing area of ​​the semiconductor processing chamber; depositing a transition metal and a carbon material on a substrate disposed within the processing area of ​​the semiconductor processing chamber — the transition metal and the carbon material are characterized by a transition metal concentration of about 5 at.% or more —; and ashing the transition metal and the carbon material from the substrate — the ashing is performed using ozone or plasma-enhanced oxygen —.

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