Metal-doped boron film

Abstract

An exemplary deposition method may include delivering a boron-containing precursor to a processing region of a semiconductor processing chamber. The method may include delivering a dopant-containing precursor with the boron-containing precursor. The dopant-containing precursor may include a metal. The method may include forming a plasma of all the precursors in the processing region of the semiconductor processing chamber. The method may include depositing a doped boron material on a substrate disposed in the processing region of the semiconductor processing chamber. The doped boron material may include about 80 atomic % or more of boron in the doped boron material.

Description

Technical Field

[0001] Cross-Reference to Related Applications

[0001] This application claims the benefit and priority of U.S. Patent Application No. 17 / 240,395, filed Apr. 26, 2021, entitled "METAL-DOPED BORON FILMS", the entire disclosure of which is incorporated herein by reference.

[0002]

[0002] This technology relates to semiconductor deposition processes. More specifically, this technology relates to methods of depositing materials having metal dopants that can be used as masking materials.

Background Art

[0003]

[0003] Integrated circuits are enabled by a process of creating complexly patterned material layers on a substrate surface. To create patterned structures on a substrate, a controlled method of forming and removing exposed materials is required. As device miniaturization progresses and structures become more complex, material properties can affect subsequent processes. For example, masking materials can affect not only the ability to develop structures but also the ability to selectively remove materials.

[0004]

[0004] Therefore, there is a need for improved systems and methods that can be used to manufacture high-quality devices and structures. This technology addresses these and other needs.

Summary of the Invention

[0005]

[0005] An exemplary deposition method may include supplying a boron-containing precursor to a processing area of ​​a semiconductor processing chamber. The method may include supplying a dopant-containing precursor together with the boron-containing precursor. The dopant-containing precursor may contain a metal. The method may include forming a plasma of all precursors within the processing area of ​​the semiconductor processing chamber. The method may include depositing a doped boron material on a substrate placed within the processing area of ​​the semiconductor processing chamber. The doped boron material may contain about 80 atomic percent (at.%) or more of boron.

[0006]

[0006] In some embodiments, the concentration of metal dopant in the film (film of doped boron material) can be maintained at about 20 atomic percent or less. The metal in the dopant-containing precursor may be one or more of tungsten, molybdenum, titanium, aluminum, cobalt, ruthenium, or tantalum, or may contain these. The dopant-containing precursor may be tungsten hexafluoride or tungsten hexacarbonyl, or may contain these. The doped boron material may be characterized by an extinction coefficient at 633 nm of about 0.45 or less. The method may include supplying an oxygen-containing precursor or a nitrogen-containing precursor together with the boron-containing precursor. The oxygen content or nitrogen content in the doped boron material may be maintained at about 10% or less. The doped boron material may be characterized by a hardness of about 25 GPa or more. The substrate may contain silicon oxide. The deposition method may include etching the silicon oxide. Silicon oxide can be etched at a rate approximately five times faster than that at which doped boron materials are etched.

[0007]

[0007] Some embodiments of the present technology may encompass deposition methods. The method may include supplying a boron-containing precursor to a processing area of ​​a semiconductor processing chamber. The method may include forming a plasma of the boron-containing precursor within the processing area of ​​the semiconductor processing chamber. The method may include forming a first layer of the boron-containing material on a substrate placed within the processing area of ​​the semiconductor processing chamber. The method may include adding a dopant-containing precursor together with the boron-containing precursor. The dopant-containing precursor may include a metal. The method may include forming a second layer of doped boron material on the first layer of the boron-containing material to produce a bilayer film.

[0008]

[0008] In some embodiments, the concentration of the metal dopant in the second layer of the bilayer film can be maintained at about 10 atomic percent or less. The metal in the dopant-containing precursor may be one or more of tungsten, molybdenum, titanium, aluminum, cobalt, ruthenium, or tantalum, or may contain these. The second layer of doped boron material may be about 50% or more of the thickness of the bilayer film. The doped boron material may be characterized by a hardness of about 25 GPa or more. The substrate may contain silicon oxide. The deposition method may include etching the silicon oxide. The silicon oxide may be etched at a rate of about 1.5 times or more the rate at which the bilayer film is etched.

[0009]

[0009] Some embodiments of the present technology may encompass a deposition method. The method may include supplying a boron-containing precursor to a processing area of ​​a semiconductor processing chamber. The method may include supplying a dopant-containing precursor together with the boron-containing precursor. The dopant-containing precursor may contain a metal. The method may include forming a plasma of all precursors within the processing area of ​​the semiconductor processing chamber. The method may include depositing the doped boron material on a substrate placed within the processing area of ​​the semiconductor processing chamber. In some embodiments, the doped boron material may contain about 10 atomic percent or less of metal. The metal in the dopant-containing precursor may include one or more of tungsten, molybdenum, titanium, aluminum, cobalt, ruthenium, or tantalum. The doped boron material may be characterized by having an extinction coefficient of about 0.45 or less at 633 nm. The substrate may contain silicon oxide. The deposition method may include etching the silicon oxide. Silicon oxide can be etched at a rate approximately five times faster than that at which doped boron materials are etched.

[0010]

[0010] Such technologies may offer many advantages over conventional systems and technologies. For example, this process may produce films characterized by improved selectivity for underlying materials. Furthermore, the steps of the embodiments of this technology may produce improved mask materials that facilitate processing steps. These embodiments and other embodiments, along with many of their advantages and features, will be described in more detail in conjunction with the following description and accompanying drawings.

[0011]

[0011] The nature and advantages of the disclosed technology can be further understood by referring to the remainder of this specification and the drawings. [Brief explanation of the drawing]

[0012] [Figure 1]

[0012] A schematic cross-sectional view of an exemplary processing chamber according to several embodiments of the present technology is shown. [Figure 2]

[0013] The following are exemplary steps in a deposition method according to several embodiments of this technology. [Modes for carrying out the invention]

[0013]

[0014] Several diagrams are included as schematic representations. It should be understood that the diagrams are for illustrative purposes only and should not be considered to scale unless explicitly stated otherwise. Furthermore, as schematic representations, the diagrams are provided to aid understanding and may not include all aspects or information compared to realistic depictions, and may include materials that are exaggerated for illustrative purposes.

[0014]

[0015] In the attached drawings, similar components and / or features may have the same reference numeral. Furthermore, various components of the same kind may be distinguished according to their reference numerals by letters that distinguish similar components from each other. Where only the first reference numeral is used in this specification, its description is applicable to any of the similar components having the same first reference numeral, regardless of the letters used.

[0015]

[0016] During semiconductor manufacturing, structures can be created on a substrate using various deposition and etching processes. Mask materials can be used to at least partially etch the material, allowing features to be generated across the entire substrate. As devices become smaller and the selectivity between materials improves, making structure formation easier, improved hard masks can facilitate manufacturing. For example, future DRAM nodes may require taller capacitor structures, which may involve forming deeper trenches on the substrate. Conventional hard masks may reach their limits in terms of selectivity for the underlying silicon material. Therefore, many semiconductor manufacturing processes are attempting to develop mask materials characterized by increased hardness and the use of thicker hard mask films for larger vertical device structures. However, while hard masks may feature sufficient transparency at a certain thickness, the transparency of the film may decrease as the thickness increases. If the film transparency is insufficient, additional processes may be required to leave areas near alignment markers open to ensure correct orientation. Furthermore, thicker hard mask films make patterning more difficult, which can then affect the uniformity of transfer to the underlying structure.

[0016]

[0017] This technology can overcome these limitations by generating mask materials that incorporate metal dopants. While counterintuitive, these materials may reduce transparency and hardness, but they offer increased selectivity for the underlying material, allowing for reduced mask thickness and overall improved etching and structuring of semiconductor substrates. Since this technique can be used to improve many film formation processes and is applicable to various processing chambers and operations, it should be understood that this technology is not intended to be limited to the specific films and processes described.

[0017]

[0018] Figure 1 shows a cross-sectional view of an exemplary processing chamber 100 according to several embodiments of the present technology. This figure may illustrate a system capable of incorporating one or more aspects of the present technology and / or performing one or more steps according to embodiments of the present technology. Additional details of the chamber 100 or the method performed may be described further below. While the chamber 100 may be used to form a film layer according to several embodiments of the present technology, it will be understood that the method may be similarly performed in any chamber in which 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 lid assembly 106 connected to the chamber body 102 and surrounding the substrate support 104 in the processing space 120. The substrate 103 may be provided to the processing space 120 through an opening 126, which may be conventionally sealed for processing using a slit valve or door. The substrate 103 may be placed on the surface 105 of the substrate support during processing. The substrate support 104 may be rotatable along an axis 147 in which the shaft 144 of the substrate support 104 may be located, as indicated by the arrow 145. Alternatively, the substrate support 104 may be lifted to rotate as needed during the deposition process.

[0018]

[0019] The plasma profile modulator 111 may be located within the processing chamber 100 to control the plasma distribution across the substrate 103 placed on the substrate support 104. The plasma profile modulator 111 may include a first electrode 108 located adjacent to the chamber body 102, which can isolate the chamber body 102 from other components of the lid assembly 106. The first electrode 108 may be part of the lid assembly 106 or 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 outer circumference of the processing chamber 100 surrounding the processing space 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 flat plate electrode, such as a secondary gas distributor.

[0019]

[0020] One or more isolators 110a, 110b, which may be dielectric materials such as ceramics or metal oxides, such as aluminum oxide and / or aluminum nitride, may contact the first electrode 108 to electrically and thermally isolate the first electrode 108 from the gas distributor 112 and the chamber body 102. The gas distributor 112 may define openings 118 for distributing the process precursor into the processing space 120. The gas distributor 112 may be connected to a first power source 142, such as an RF generator, an RF power supply, a DC power supply, a pulsed DC power supply, a pulsed RF power supply, or any other power supply that may be connected to the processing chamber. In some embodiments, the first power source 142 may be an RF power supply.

[0020]

[0021] The gas distributor 112 may be a conductive or non-conductive gas distributor. Furthermore, the gas distributor 112 may be formed from conductive and non-conductive components. For example, the body of the gas distributor 112 may be conductive, while the faceplate of the gas distributor 112 is non-conductive. The gas distributor 112 may be powered by a first power source 142, such as shown in Figure 1, or, in some embodiments, the gas distributor 112 may be connected to earth.

[0021]

[0022] The first electrode 108 may be connected to a first tuning circuit 128 that can control the grounding 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 element, or may include one. The first tuning circuit 128 may be one or more inductors 132, or may include one. The first tuning circuit 128 may be any circuit that enables a variable or controllable impedance under the plasma conditions present in the processing space 120 during processing. In some embodiments as illustrated, the first tuning circuit 128 may include a first circuit leg and a second circuit leg connected 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 connected in series with the first electronic controller 134. A second inductor 132B may be positioned between the first electronic controller 134 and a node that couples both the first and second circuit legs to the first electronic sensor 130. The first electronic sensor 130 is a voltage or current sensor connected to the first electronic controller 134 and may allow for some degree of closed-loop control of the plasma conditions inside the processing space 120.

[0022]

[0023] The second electrode 122 may be connected to the substrate support 104. The second electrode 122 may be embedded within the substrate support 104 or connected 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 other distributed arrangement of conductive elements. The second electrode 122 may also be a tuning electrode and may be connected to a second tuning circuit 136 by a conduit 146, such as a cable with a selected resistance, such as 50 ohms, located within the shaft 144 of the substrate support 104. The second tuning circuit 136 may have a second electronic sensor 138 and a second electronic controller 140, the second electronic controller 140 may be a second variable capacitor. The second electronic sensor 138 is a voltage or current sensor and may be connected to the second electronic controller 140 to provide further control over the plasma conditions in the processing space 120.

[0023]

[0024] A third electrode 124, which may be a bias electrode and / or an electrostatic chuck electrode, may be connected to a substrate support 104. The third electrode is connected 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.

[0024]

[0025] The lid assembly 106 and the substrate support 104 of FIG. 1 can be used with any processing chamber for plasma or heat treatment. In operation, the processing chamber 100 can allow for real-time control of plasma conditions within the processing space 120. The substrate 103 is disposed on the substrate support 104, and process gas can be flowed through the lid assembly 106 using the inlet 114 according to any desired flow plan. The gas can exit the processing chamber 100 through the outlet 152. Power can be connected to the gas distributor 112 to establish plasma within the processing space 120. The substrate can receive an electrical bias using a third electrode 124 in some embodiments.

[0025]

[0026] When the plasma within the processing space 120 is excited, a potential difference can be established between the plasma and the first electrode 108. Also, a potential difference can be established between the plasma and the second electrode 122. Next, the electronic controllers 134, 140 can be used to adjust the flow characteristics of the ground path represented by the two tuning circuits 128, 136. Set points can be provided to the first tuning circuit 128 and the second tuning circuit 136 to perform independent control of the deposition rate and independent control of the uniformity of plasma density from the center to the edge. In embodiments where both electronic controllers can be variable capacitors, the electronic sensor can independently adjust the variable capacitors to maximize the deposition rate and minimize thickness non-uniformity.

[0026]

[0027] Each of the tuning circuits 128, 136 may have a variable impedance that can be adjusted using respective 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 can be selected to provide an impedance range. This range depends on the frequency characteristics and voltage characteristics of the plasma, and there may be 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, the impedance of the first tuning circuit 128 becomes high, and a plasma shape with a minimum aerial or lateral coverage on the substrate support may be brought about. As the capacitance of the first electronic controller 134 approaches a value that minimizes the impedance of the first tuning circuit 128, the aerial coverage of the plasma grows to a maximum and may effectively cover the entire working area of the substrate support 104. When the capacitance of the first electronic controller 134 deviates from the minimum impedance setting, the plasma shape may contract from the chamber wall and the aerial coverage of the substrate support may decrease. The second electronic controller 140 has a similar effect, and since the capacitance of the second electronic controller 140 can be changed, the aerial coverage of the plasma on the substrate support can be increased or decreased.

[0027]

[0028] The electronic sensors 130, 138 may be used to adjust the respective circuits 128, 136 in a closed loop. Depending on the type of sensor used, a set point of current or voltage is set in each sensor, and control software that determines the adjustment to each respective electronic controller 134, 140 to minimize the deviation from the set point may be provided to the sensor. As a result, during processing, the plasma shape can be selected and dynamically controlled. The foregoing discussion is based on the electronic controllers 134, 140 that may be variable capacitors, but it will be understood that any electronic component with adjustable characteristics may be used to provide the tuning circuits 128, 136 with adjustable impedance.

[0028]

[0029] Figure 2 shows exemplary steps in the deposition method 200 according to several embodiments of the present technology. The method can be carried out in various processing chambers, including the processing chamber 100 described above. Method 200 may include a number of optional steps, which may or may not be particularly related to some embodiments of the method according to the present technology. For example, many of the steps are described to provide a broader range of structure formation, but may be carried out by alternative methodologies that are not important to the present technology or that would be easily understood.

[0029]

[0030] Method 200 may include additional steps before commencing the listed steps. For example, the additional processing steps may include forming a structure on the semiconductor substrate, which may include both forming and removing material. The prior processing steps may be performed in the chamber in which Method 200 may be performed, or the processing may be performed in one or more other processing chambers before the substrate is brought into the semiconductor processing chamber in which Method 200 may be performed. In any case, Method 200 may optionally include supplying the semiconductor substrate to the processing area of ​​a semiconductor processing chamber such as the processing chamber 100 described above, or to the processing area of ​​another chamber which may include the components described above. The substrate may be a pedestal such as the substrate support 104, and may be deposited on the substrate support, which may be placed in the processing area of ​​a chamber such as the processing space 120 described above.

[0030]

[0031] The substrate may be or may include any number of materials on which material can be deposited. The substrate may be a dielectric material containing silicon, germanium, silicon oxide, or silicon nitride, a metallic material, or any number of combinations of these materials, which may be a substrate or a material formed on a substrate. In some embodiments, optional processing steps, 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 ends on the surface of the substrate. This may promote nucleation of the film to be deposited. For example, other molecular ends, including hydrogen, oxygen, carbon, nitrogen, or any combination of these atoms or radicals, may be adsorbed, reacted, or formed on the surface of the substrate. In addition, material removal may be performed, such as reduction of native oxides or etching of the material, or any other steps that may prepare one or more exposed surfaces of the substrate for deposition.

[0031]

[0032] In step 205, one or more precursors may be supplied to the processing area of ​​the chamber. For example, the film to be deposited may be a mask film used in semiconductor processes. The deposition precursor may include any number of mask precursors, including one or more boron-containing precursors. The precursors may be flowed together or separately. For example, in an exemplary embodiment in which a boron-containing film can be formed, at least one boron-containing precursor may be supplied to the processing area of ​​the processing chamber. Plasma-enhanced deposition is performed in some embodiments of the art, which may accelerate material reactions and deposition. For example, in step 210, a plasma may be formed from the boron-containing precursor, and in an optional step 215, the boron-containing material may be deposited.

[0032]

[0033] Boron-containing hard masks are characterized by relatively high hardness, which can improve etching selectivity. However, to further improve etching selectivity for underlying silicon-containing materials such as silicon oxide or silicon nitride, this technology can incorporate one or more dopant materials, which may contain one or more metals. Incorporating metals can be counterintuitive in terms of hard mask formation, particularly for the purpose of improving properties for selective etching. For example, incorporating metals into a hard mask can actually decrease the hardness of the film, and many conventional technologies avoid this in order to obtain a harder mask film. Furthermore, metal dopants can reduce the transparency of the film, making the lithography process more difficult by producing a more opaque film. Thus, it may be difficult to increase the thickness of the mask as has been done conventionally. However, current technologies can overcome the decrease in film hardness by utilizing metal dopants to enhance the selectivity of the etching process. Furthermore, since etching selectivity may be improved compared to non-metallic doped films, masks according to some embodiments of this technology may be characterized by reduced thickness, which can improve the transparency of the film. For example, the prior art may provide thicker hard masks in an attempt to increase the depth of the structure formed. As silicon, boron, and germanium films thicken, these films are characterized by increased opacity, which can make lithography difficult. By incorporating metallic materials, this technology may overcome the need to thicken the mask film.

[0033]

[0034] Accordingly, some embodiments of this technology may include, in step 220, the additional supply of a dopant-containing precursor supplied together with other deposition precursors. The supplied precursor may all be used to form plasma within the processing area of ​​the semiconductor processing chamber in operation 210, as described above. Thus, the sequence of steps as shown in method 200 may include operations performed in different sequences, including simultaneously. In step 225, a material containing a metal dopant within the deposited material may be deposited on the substrate. By incorporating a dopant-containing precursor, etching selectivity may be increased, while films with controlled hardness and transparency may be produced.

[0034]

[0035] Depending on the precursor used, the flow rate of the dopant precursor may be used to control the dopant content. For example, in the case of transition metal dopants, the flow rate of other deposition precursors may be several hundred sccm or more, while the dopant precursor may be supplied at a flow rate of approximately 250 sccm or less, approximately 200 sccm or less, approximately 150 sccm or less, approximately 100 sccm or less, approximately 50 sccm or less, approximately 40 sccm or less, approximately 30 sccm or less, approximately 25 sccm or less, approximately 20 sccm or less, approximately 15 sccm or less, approximately 10 sccm or less, approximately 5 sccm or less, or even lower.

[0035]

[0036] With respect to boron-containing precursors, any number of precursors can be used in this technology. For example, boron-containing materials may include borane, diborane, or other multi-center-bonded boron materials, as well as any other boron-containing materials that can be used to produce boron-containing materials. The boron content in the resulting film may be based on any percentage. For example, a resulting film containing a film that is substantially or essentially boron and has a smaller amount of dopants in the film may contain a boron content of about 50% or more, and in some embodiments, may contain a boron content of about 55% or more, about 60% or more, about 65% or more, about 70% or more, about 75% or more, about 80% or more, about 85% or more, about 90% or more, about 95% or more, or more. It should be understood that while trace amounts of substances may be incorporated into the membrane by exposure to the atmosphere or other process environments, the membrane can still fundamentally remain boron-based.

[0036]

[0037] The dopant precursor may include any metal-containing precursor, such as any metal or transition metal that can be supplied to the processing region in a stable form. Exemplary dopants may include one or more of tungsten, molybdenum, titanium, aluminum, cobalt, ruthenium, tantalum, or other metals or transition metals that can be combined with boron in the mask material. The exemplary precursor may include any number of metal-containing materials. These metal-containing materials may be dissociated in the plasma to supply metal dopants for incorporation. For example, non-limiting examples of dopant-containing precursors that may be used in embodiments of the present technology include tungsten hexafluoride, tungsten hexacarbonyl, molybdenum hexafluoride, molybdenum pentachloride, molybdenum hexacarbonyl, titanium tetrachloride, tetrakis(dimethylamide)titanium, titanium tetrafluoride, trimethylaluminum, aluminum chloride, bis(N,N'-diisopropylacetamidinato)cobalt, cobaltosene, bis(ethylcyclopentadienyl)cobalt, bis(pentamethylcyclopentadienyl)cobalt, bis(cyclopentadienyl)ruthenium, bis(ethylcyclopentadienyl)ruthenium, tantalum pentachloride, pentakis(dimethylamide)tantalum, or any other metal-containing precursors that may be used to provide metal dopant materials for incorporation into boron-containing materials.

[0037]

[0038] In some embodiments, the deposited doped boron material may consist substantially or essentially of one or more metal dopant materials and boron. Furthermore, in some embodiments, an additional dopant precursor may be supplied along with the metal-containing precursor, which may contain oxygen or nitrogen, or any other dopants that can modulate the structure of the deposited film to improve transparency, stress, hardness, and heat resistance. In embodiments of this technology, any number of nitrogen-containing precursors or oxygen-containing precursors may be used. Furthermore, combination precursors containing multiple of these elements may be used. For example, an oxygen-containing precursor used in some embodiments is nitrous oxide, which can provide both oxygen and nitrogen for incorporation into the film. The dopant content is within any range, which may relate to the extinction coefficient, where a higher dopant content results in a lower extinction coefficient of the formed film. In some embodiments, the dopants may be selected considering their compatibility with other deposition precursors.

[0038]

[0039] One or more dopants are included in any amount or concentration, individually or collectively, in the deposited film at a concentration of about 1 atomic percent or more, and in some embodiments, they may be present at concentrations of about 2 atomic percent or more, about 3 atomic percent or more, about 4 atomic percent or more, about 5 atomic percent or more, about 6 atomic percent or more, about 7 atomic percent or more, about 8 atomic percent or more, about 9 atomic percent or more, about 10 atomic percent or more, about 11 atomic percent or more, about 12 atomic percent or more, about 13 atomic percent or more, about 14 atomic percent or more, about 15 atomic percent or more, about 16 atomic percent or more, about 17 atomic percent or more, about 18 atomic percent or more, about 19 atomic percent or more, about 20 atomic percent or more, or more. However, as described above, metal dopants can reduce not only hardness but also transparency, so in some embodiments, the metal dopant concentration may be maintained at about 20 atomic percent or less, about 15 atomic percent or less, about 12 atomic percent or less, about 10 atomic percent or less, or less. Oxygen and / or nitrogen dopants are similarly maintained within the aforementioned ranges, which may further refine the film properties. While oxygen and / or nitrogen content may improve the extinction coefficient or film stress, this material may reduce etching selectivity. Therefore, oxygen and nitrogen content may be limited or excluded to maintain higher etching selectivity. The deposition precursor may contain additional hydrogen precursors, such as diatomic hydrogen, which may affect the transparency of the film. Furthermore, one or more carrier gases, such as argon, may be supplied to facilitate the deposition process.

[0039]

[0040] Furthermore, the temperature of the substrate may also affect deposition. For example, in some embodiments, during deposition, the substrate may be maintained at a temperature of approximately 300°C or higher, approximately 325°C or higher, approximately 350°C or lower, approximately 375°C or higher, approximately 400°C or higher, approximately 425°C or higher, approximately 450°C or higher, approximately 475°C or higher, approximately 500°C or higher, approximately 525°C or higher, approximately 550°C or higher, approximately 575°C or higher, approximately 600°C or higher, or higher. By performing deposition according to some embodiments of the present technology, the hydrogen content in the film may be reduced or limited. An increase in hydrogen content can increase compressive stress in the film, and therefore, films according to embodiments of the present technology may feature greater tensile properties due to the reduced hydrogen content. Furthermore, in some embodiments, method 200 may include a step that can further reduce the hydrogen content in the film. Unlike some prior art, by incorporating dopants according to embodiments of the present technology, in some embodiments, damage from subsequent processing, such as thermal annealing after deposition of the hard mask material, may be reduced or limited.

[0040]

[0041] As described above, this technology can enhance the selectivity of hard mask films while limiting the decrease in hardness. For example, metal-doped boron-containing materials according to some embodiments of this technology are characterized by a film hardness maintained at about 20 GPa or higher, and can be maintained at about 22 GPa or higher, about 24 GPa or higher, about 26 GPa or higher, about 28 GPa or higher, about 30 GPa or higher, about 32 GPa or higher, about 34 GPa or higher, about 36 GPa or higher, about 38 GPa or higher, about 40 GPa or higher, about 42 GPa or higher, about 44 GPa or higher, or higher, despite the incorporation of some metal materials that can reduce film hardness. Furthermore, the selectivity of this film can be improved during subsequent etching processes. For example, in some embodiments, method 200 may further include a step of etching the material on the substrate. For example, in some embodiments, the doped boron mask material may be formed on a silicon-containing material such as silicon oxide or silicon nitride.

[0041]

[0042] In some embodiments, method 200 may include an etching process in an optional step 230. This etching process may etch the underlying silicon oxide, silicon nitride, a combination thereof, or other structural materials that can be etched with a hard mask according to the Art. In some embodiments, the metal-doped boron-containing material may be characterized by etching selectivity for the underlying oxide and / or nitride material such that the underlying material can be etched at a rate about twice or more than the rate at which the metal-doped boron-containing material can be etched. Furthermore, silicon oxide or silicon nitride can be etched at approximately 3.0 times or more the rate at which metal-doped boron-containing materials can be etched, and at approximately 3.5 times, 4.0 times, 4.5 times, 5.0 times, 5.5 times, 6.0 times, 6.5 times, 7.0 times, 7.5 times, 8.0 times, 8.5 times, 9.0 times, 9.5 times, and 10.0 times or more the rate at which metal-doped boron-containing materials can be etched. This can be at least twice as selective to the underlying film compared to other hard mask materials such as amorphous silicon. As a result, by increasing the etching selectivity to the underlying film, the thickness of the metal-doped boron-containing material can be made thinner, and the transparency of the film can be improved or maintained despite the incorporation of metal material.

[0042]

[0043] Metal-containing hard mask films according to some embodiments of this technology are characterized by their extinction coefficients for light of different wavelengths, which can affect the lithography process. By controlling the dopant content to limit the thickness of the mask according to embodiments of this technology, including the addition of oxygen dopant and / or nitrogen dopant, the extinction coefficient at 633 nm can be reduced to about 0.45 or less, and can be reduced to about 0.44 or less, about 0.43 or less, about 0.42 or less, about 0.41 or less, about 0.40 or less, about 0.39 or less, about 0.38 or less, about 0.37 or less, about 0.36 or less, about 0.35 or less, about 0.34 or less, about 0.33 or less, about 0.32 or less, about 0.31 or less, about 0.30 or less, about 0.29 or less, about 0.28 or less, about 0.27 or less, about 0.26 or less, about 0.25 or less, or below. This allows lithography to be extended to thicknesses of approximately 300 nm or more, approximately 350 nm or more, approximately 400 nm or more, or even greater, without performing an additional alignment key opening operation.

[0043]

[0044] Furthermore, some embodiments of the technology may produce a two-layer hard mask that can further limit the influence of metallic material content while providing improved selectivity with respect to the material being etched. For example, as described earlier in the optional deposition step 215, method 200 may first include forming a plasma of one or more boron-containing precursors in a semiconductor processing area. This process may include maintaining a state in which the processing area is free of metal-containing dopant precursors during this initial process. This allows a boron-containing layer to be deposited first on the semiconductor substrate. The first layer may be formed to a first thickness on the semiconductor substrate while maintaining a state free of metal dopants. Subsequently, after a first period for developing the thickness of the first layer, dopant precursors may then be supplied in step 220. Thereafter, a second layer containing boron-doped material may be deposited on the first layer of boron-containing film to produce a two-layer film or hard mask. The plasma and flow of the boron-containing precursor can be maintained throughout the process by adding a dopant-containing precursor following the first period. Deposition can then proceed over a second period until a second layer, which may be a metal-doped layer, of a desired thickness is obtained.

[0044]

[0045] The first and second periods may be based on the desired thickness of the layers. For example, in some embodiments, the first period may be less than or equal to the second period. Here, the two resulting layers may have equal thickness, or the second doped layer may be thicker than the first layer. Therefore, in some embodiments, the second layer of doped boron material is about 25% or more of the thickness of the bilayer film, and the second layer may be about 30% or more of the thickness of the bilayer film, about 35% or more of the thickness of the bilayer film, about 40% or more of the thickness of the bilayer film, about 45% or more of the thickness of the bilayer film, about 50% or more of the thickness of the bilayer film, about 55% or more of the thickness of the bilayer film, about 60% or more of the thickness of the bilayer film, about 65% or more of the thickness of the bilayer film, about 70% or more of the thickness of the bilayer film, about 75% or more of the thickness of the bilayer film, about 80% or more of the thickness of the bilayer film, about 85% or more of the thickness of the bilayer film, about 90% or more of the thickness of the bilayer film, or more. By utilizing metal-doped mask materials according to embodiments of the present technology, selectivity can be improved to facilitate production at future process nodes.

[0045]

[0046] The above description provides numerous details for illustrative purposes to facilitate understanding of various embodiments of this technology. However, it will be apparent to those skilled in the art that certain embodiments can be implemented without some of these details, or with additional details.

[0046]

[0047] While several embodiments have been disclosed, those skilled in the art will recognize that various modifications, alternative structures, and equivalents can be used without departing from the spirit of the embodiments. Furthermore, some well-known processes and elements have not been described in order to avoid unnecessarily obscuring the Art. Therefore, the above description should not be construed as limiting the scope of the Art. Moreover, while methods or processes may be described sequentially or stepwise, it should be understood that the actions may occur simultaneously or in an order different from that listed.

[0047]

[0048] Where a range of values ​​is given, unless explicitly stated otherwise in the context, each intervening value between the upper and lower limits of that range is understood to be specifically disclosed down to the smallest unit of the lower limit. This includes any narrower range between any stated or unstated intervening values ​​within the stated range, and any other stated or intervening values ​​within that stated range. The upper and lower limits of such narrower ranges may be individually included in or excluded from that range. Each range in which one, neither, or both of the limit values ​​are included is also included in the Art, provided that there are limit values ​​specifically excluded within the stated range. If the stated range includes one or both of the limit values, it also includes ranges that exclude one or both of these included limit values.

[0048]

[0049] As used herein and in the claims, the singular forms “a,” “an,” and “the” include multiple references unless the context clearly indicates otherwise. Thus, for example, a reference to “precursor” includes multiple such precursors, and a reference to “layer” includes one or more layers and their equivalents, etc., that are well known to those skilled in the art.

[0049]

[0050] Furthermore, the terms “comprise(s),” “comprising,” “contain(s),” “containing,” “include(s),” and “including,” as used herein and in the claims, are intended to identify the presence of the described feature, integer, component, or process, but not to exclude the presence or addition of one or more other features, integers, components, processes, actions, or groups.

Claims

1. The boron-containing precursor is supplied to the processing area of ​​the semiconductor processing chamber, The method of supplying a dopant-containing precursor together with the boron-containing precursor, wherein the dopant-containing precursor contains a metal, Forming plasma of all precursors within the processing region of the semiconductor processing chamber, The method involves depositing a doped boron material on a substrate placed within the processing area of ​​the semiconductor processing chamber, wherein the doped boron material contains 80 atomic percent or more of boron. A deposition method that includes [specific type of deposition].

2. The deposition method according to claim 1, wherein the concentration of the metal dopant in the film is maintained at 20 atomic percent or less.

3. The deposition method according to claim 1, wherein the metal in the dopant-containing precursor comprises one or more of tungsten, molybdenum, titanium, aluminum, cobalt, ruthenium, or tantalum.

4. The deposition method according to claim 3, wherein the dopant-containing precursor comprises tungsten hexafluoride or tungsten hexacarbonyl.

5. The deposition method according to claim 1, characterized in that the doped boron material has an extinction coefficient of 0.45 or less at 633 nm.

6. The deposition method according to claim 1, further comprising supplying an oxygen-containing precursor or a nitrogen-containing precursor together with the boron-containing precursor.

7. The deposition method according to claim 6, wherein the oxygen content or nitrogen content in the doped boron material is maintained at 10% or less.

8. The deposition method according to claim 1, wherein the doped boron material is characterized by a hardness of 25 GPa or more.

9. The substrate contains silicon dioxide, and the deposition method is Etching the silicon dioxide The deposition method according to claim 8, further comprising, wherein the silicon oxide is etched at a rate five times or more faster than the rate at which the doped boron material is etched.

10. The boron-containing precursor is supplied to the processing area of ​​the semiconductor processing chamber, Forming a plasma of the boron-containing precursor within the processing region of the semiconductor processing chamber, Forming a first layer of boron-containing material on a substrate placed within the processing area of ​​the semiconductor processing chamber, Adding a dopant-containing precursor together with the boron-containing precursor, wherein the dopant-containing precursor contains a metal, In order to produce a two-layer film, a second layer of doped boron material is formed on the first layer of boron-containing material. A deposition method that includes [specific type of deposition].

11. The deposition method according to claim 10, wherein the concentration of the metal dopant in the second layer of the two-layer film is maintained at 10 atomic percent or less.

12. The deposition method according to claim 10, wherein the metal in the dopant-containing precursor comprises one or more of tungsten, molybdenum, titanium, aluminum, cobalt, ruthenium, or tantalum.

13. The deposition method according to claim 10, wherein the second layer of the doped boron material comprises 50% or more of the thickness of the two-layer film.

14. The deposition method according to claim 13, wherein the doped boron material is characterized by a hardness of 25 GPa or more.

15. The substrate contains silicon dioxide, and the deposition method is Etching the silicon dioxide The deposition method according to claim 10, further comprising:

16. The deposition method according to claim 15, wherein the silicon dioxide is etched at a rate of 1.5 times or more the rate at which the two-layer film is etched.

17. The boron-containing precursor is supplied to the processing area of ​​the semiconductor processing chamber, The method of supplying a dopant-containing precursor together with the boron-containing precursor, wherein the dopant-containing precursor contains a metal, Forming plasma of all precursors within the processing region of the semiconductor processing chamber, The method involves depositing a doped boron material on a substrate placed within the processing area of ​​the semiconductor processing chamber, wherein the doped boron material contains 10 atomic percent or less of metal. A deposition method that includes [specific type of deposition].

18. The deposition method according to claim 17, wherein the metal in the dopant-containing precursor comprises one or more of tungsten, molybdenum, titanium, aluminum, cobalt, ruthenium, or tantalum.

19. The deposition method according to claim 17, characterized in that the doped boron material has an extinction coefficient of 0.45 or less at 633 nm.

20. The substrate contains silicon dioxide, and the deposition method is Etching the silicon dioxide The deposition method according to claim 17, further comprising, wherein the silicon oxide is etched at a rate five times or more faster than the rate at which the doped boron material is etched.

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