REDUCED HYDROGEN DEPOSITION METHOD - Patent application

Abstract

An exemplary method for semiconductor processing may include treating a surface of a substrate with a hydrogen-containing precursor. The substrate may be placed in a processing region of a semiconductor processing chamber. The method may include contacting the substrate with a tungsten-containing precursor. The method may include forming an initiation layer containing tungsten on the substrate. The method may include treating the initiation layer with a hydrogen-containing precursor. The method may include forming a plasma of a tungsten-containing precursor and a carbon-containing precursor. Hydrogen in the plasma may be limited to hydrogen contained in the carbon-containing precursor. The method may include forming a tungsten-containing hard mask layer on the initiation layer.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of priority to U.S. patent application Ser. No. 62 / 934,289, filed Nov. 12, 2019, the contents of which are incorporated by reference in their entirety for all purposes.

[0002] Technical Field

[0002] The present technology relates to semiconductor processing methods and components. More particularly, the present technology relates to systems and methods for manufacturing hardmask films. [Background technology]

[0003] background

[0003] Integrated circuits are made possible by processes that produce intricately patterned layers of material on a substrate surface. Fabricating patterned materials on a substrate requires controlled methods for forming and removing materials. As device sizes continue to shrink, the aspect ratios of structures can become large, and maintaining the dimensions of these structures during removal operations can be difficult. To facilitate the patterning of materials on a substrate, hard masks can be employed. As the number of material layers to be patterned expands, the selectivity of hard masks to multiple materials is becoming a greater challenge.

[0004]

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

[0005]

[0005] An exemplary method of semiconductor processing can include treating a surface of a substrate with a hydrogen-containing precursor. The substrate can be disposed in a processing region of a semiconductor processing chamber. The method can include contacting the substrate with a tungsten-containing precursor. The method can include forming an initiation layer on the substrate that includes tungsten. The method can include treating the initiation layer with a hydrogen-containing precursor. The method can include forming a plasma of a tungsten-containing precursor and a carbon-containing precursor. Hydrogen in the plasma can be limited to hydrogen included in the carbon-containing precursor. The method can include forming a tungsten-containing hard mask layer on the initiation layer.

[0006] In some embodiments, treating the surface of the substrate may include forming a plasma of a hydrogen-containing precursor and contacting the surface of the substrate with effluent of the plasma to produce a hydrogen termination. The tungsten-containing precursor may be delivered for contact while treating the surface of the substrate is being performed. The flow rate of the tungsten-containing precursor may be increased while it is being delivered. Treating the initiation layer may include forming a plasma of a hydrogen-containing precursor and contacting the initiation layer with effluent of the plasma. The plasma may also include a nitrogen-containing precursor. The hydrogen-containing precursor may be or may include diatomic hydrogen, the nitrogen-containing precursor may be or may include diatomic nitrogen, the tungsten-containing precursor may be or may include tungsten hexafluoride, and the carbon-containing precursor may be or may include propene. The diatomic hydrogen may be removed from the semiconductor processing chamber during forming the plasma of the tungsten-containing precursor and the carbon-containing precursor. The method may include forming a seasoning layer including a silicon-containing material on an exposed surface of the processing region of the semiconductor processing chamber.

[0007]

[0007] Some embodiments of the present technique may include a method of semiconductor processing. The technique may include forming a seasoning layer on an exposed surface of a processing region of a semiconductor processing chamber. The method may include forming an initiation layer comprising tungsten on a substrate. The substrate may be disposed in the processing region of the semiconductor processing chamber. The method may include forming a plasma of a tungsten-containing precursor and a carbon-containing precursor. An atomic ratio of hydrogen in the precursor delivered to form the plasma to tungsten in the precursor delivered to form the plasma may be less than 8:1. The method may include forming a tungsten-containing hardmask layer on the initiation layer.

[0008]

[0008] In some embodiments, the seasoning layer may be or may include silicon oxide and silicon nitride. Forming the initiation layer may include forming a plasma of a hydrogen-containing precursor. Forming the initiation layer may include contacting the surface of the substrate with effluent of the plasma to generate a hydrogen termination. Forming the initiation layer may include flowing a tungsten-containing precursor into the processing region to contact the surface of the substrate. The tungsten-containing precursor may not be excited while flowing to contact the surface of the substrate. The method may include forming a plasma of a hydrogen-containing precursor and contacting the initiation layer with effluent of the plasma. The tungsten-containing precursor may be or may include tungsten hexafluoride, and the carbon-containing precursor may be or may include propylene. Diatomic hydrogen may be excluded from the semiconductor processing chamber during forming the plasma of the tungsten-containing precursor and the carbon-containing precursor.

[0009]

[0009] Some embodiments of the present technique may include a method of semiconductor processing. The technique may include forming a seasoning layer on an exposed surface of a processing region of a semiconductor processing chamber. The method may include treating a surface of a substrate with a hydrogen-containing precursor. The substrate may be disposed in a processing region of the semiconductor processing chamber. The method may include contacting the substrate with a tungsten-containing precursor. The method may include forming an initiation layer comprising tungsten on the substrate. The method may include treating the initiation layer with a hydrogen-containing precursor. The method may include forming a plasma of a tungsten-containing precursor and a carbon-containing precursor. Hydrogen in the plasma may be limited to hydrogen contained in the carbon-containing precursor. The method may include forming a tungsten-containing hard mask layer on the initiation layer.

[0010] In some embodiments, the method may include removing the substrate from the semiconductor processing chamber. The method may include performing a chamber clean process in a processing region of the semiconductor processing chamber. The method may include forming a plasma of an oxygen-containing precursor in the processing region of the semiconductor processing chamber.

[0011]

[0011] Such techniques may provide many advantages over conventional systems and techniques. For example, embodiments of the present technique may produce hardmask films characterized by reduced grain size. Additionally, the present technique may reduce delamination of the formed film. These and other embodiments, along with many of their advantages and features, are described in more detail in conjunction with the following description and accompanying figures.

[0012] A further understanding of the nature and advantages of the disclosed technology may be realized by reference to the remaining portions of the specification and drawings. [Brief description of the drawings]

[0013] [Figure 1] 1 shows a schematic cross-sectional view of an exemplary plasma system in accordance with some embodiments of the present technique. [Figure 2A]

[0014] 1 illustrates operations in a semiconductor processing method according to some embodiments of the present technique. [Figure 2B]

[0015] 1 illustrates operations in a semiconductor processing method according to some embodiments of the present technique. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014]

[0016] Some of the figures are included as schematics. It is understood that these figures are for illustrative purposes and should not be considered to scale unless specifically stated to be to scale. Furthermore, as schematics, the figures are provided to aid in understanding and may not include all aspects or information compared to realistic representations and may include exaggerated material for illustrative purposes.

[0015]

[0017] In the accompanying figures, similar components and / or special features may have the same reference label. Furthermore, various components of the same type may be distinguished by following the reference numbers with a letter that distinguishes the similar components. If only the first reference number is used in this specification, the description is applicable to any one of the similar components having the same first reference number, regardless of the letter.

[0016]

[0018] Hardmask films are utilized in many processing operations, including forming patterns through multiple layers of various materials. Increasing the etch selectivity of these materials to hardmask films allows for tighter control of critical dimension geometries, especially as feature sizes continue to shrink. While amorphous silicon or carbon films are often used as hardmasks, the selectivity of these films is becoming a greater challenge for more complex memory and logic structures that may have multiple different films on a substrate and may require patterning into high aspect ratio features. Thus, newer films may include incorporating metallic materials within the film to increase etch selectivity. As one non-limiting example, the incorporation of tungsten into carbon films can increase selectivity compared to many oxide and nitride materials. However, the increased incorporation of tungsten into the film can cause a number of problems.

[0017]

[0019] Tungsten and other metal-containing materials can be deposited using metal halide precursors. In the case of tungsten, tungsten hexafluoride can be used for deposition in plasma enhanced chemical vapor deposition. During plasma deposition, residual fluorine can become incorporated into the crystal structure and can diffuse through the film to the hard mask interface with the substrate. This can reduce film adhesion and cause undercutting during subsequent etching, resulting in film delamination and device failure. To limit adhesion issues, many conventional techniques may utilize hydrogen during the deposition process, which may accept residual fluorine and extract it from the chamber as a volatile by-product.

[0018]

[0020] Incorporating hydrogen into the film can cause additional problems during processing. For example, hydrogen incorporated into the film has poor thermal stability and can lead to outgassing during subsequent processing. Additionally, hydrogen can affect the stress of the film, making it more compressible, which can also lead to film delamination. Finally, the volume of hydrogen in the plasma can affect the deposition process, leading to an increase in grain size and crystallinity of the formed tungsten and carbon films. For example, conventional processes can be characterized by grain sizes of 2 nm or greater. As critical dimension features are reduced to 20 nm or less, these grain sizes can increase surface roughness, leading to increased line edge roughness and line width roughness during etching operations. Additionally, larger grain structures can cause effective twisting during the formation of higher aspect ratio features, which can affect subsequent operations by reducing the uniformity of the critical dimensions.

[0019]

[0021] To improve the film grain problem, some conventional processes have taken corrective measures. For example, conventional techniques may reduce the incorporation of tungsten, perform multiple deposition operations, or introduce boron doping. All of these modifications may have adverse effects on the process. For example, if the tungsten percentage is reduced, the etch selectivity of the film may also decrease. Multiple deposition operations may increase queue times, and boron incorporation may decrease the extinction coefficient of the film.

[0020]

[0022] The present technique overcomes these problems by performing tungsten deposition without utilizing additional hydrogen gas during the deposition process. The technique can improve adhesion by forming an initiation layer on the substrate surface. When forming the bulk of the hardmask film, removing hydrogen from the deposition process can allow a greater number of nucleation sites to form and reduce grain size as the film growth progresses. The technique can also perform chamber cleaning, treatment, and seasoning to further improve deposition and reduce falling particles.

[0021]

[0023] While the remaining disclosure routinely identifies a particular deposition process utilizing the disclosed technology, it will be readily understood that the systems and methods are equally applicable to other deposition, etch, and cleaning chambers and processes that may occur in the described chambers. Thus, the technology should not be considered limited for use with only these particular deposition processes or chambers. This disclosure discusses one possible chamber that may be used to perform processes according to embodiments of the technology before additional modifications and adjustments to this system according to embodiments of the technology are described.

[0022]

[0024] FIG. 1 illustrates a cross-sectional view of an exemplary processing chamber 100 according to some embodiments of the present technology. The diagram may provide an overview of a system that may incorporate one or more aspects of the present technology and / or be specifically configured to perform one or more operations according to embodiments of the present technology. Additional details of the chamber 100 or the method performed may be further described below. Although the chamber 100 may be utilized to form a film layer according to some embodiments of the present technology, it should be understood that the method may similarly be 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 within the chamber body 102, and a lid assembly 106 coupled with the chamber body 102 and enclosing the substrate support 104 in a processing volume 120. The substrate 103 may be provided in the processing volume 120 through an opening 126, which may be conventionally sealed for processing using a slit valve or door. The substrate 103 may be seated on a surface 105 of the substrate support during processing. The substrate support 104 may be rotatable along an axis 147 about which the shaft 144 of the substrate support 104 may be disposed, as indicated by arrow 145. Alternatively, the substrate support 104 may be elevated to rotate as needed during the deposition process.

[0023]

[0025] The plasma profile modulator 111 may be disposed in the process chamber 100 to control the plasma distribution across the substrate 103 disposed on the substrate support 104. The plasma profile modulator 111 may include a first electrode 108 that may be disposed adjacent to the chamber body 102, which may be isolated from other components of the lid assembly 106. The first electrode 108 may be part of the lid 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 process chamber 100 surrounding the process volume 120, or may be discontinuous at selected locations as needed. The first electrode 108 may also be a perforated electrode, such as a perforated ring or mesh electrode, or may be a plate electrode, such as a secondary gas distributor, for example.

[0024]

[0026] One or more isolators 110a, 110b, which may be a dielectric material such as ceramic or metal oxide, e.g., aluminum oxide and / or aluminum nitride, may contact the first electrode 108 and electrically and thermally isolate the first electrode 108 from the gas distributor 112 and the chamber body 102. The gas distributor 112 may define an aperture 118 for distributing the process precursors into the processing volume 120. The gas distributor 112 may be coupled to a first power source 142, such as 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 capable of being coupled to a processing chamber. In some embodiments, the first power source 142 may be an RF power source.

[0025]

[0027] The gas distributor 112 can be a conductive gas distributor or a non-conductive gas distributor. The gas distributor 112 can also be formed from conductive and non-conductive components. For example, the body of the gas distributor 112 can be conductive while the faceplate of the gas distributor 112 can be non-conductive. The gas distributor 112 can be powered, such as by a first power source 142 as shown in FIG. 1, or the gas distributor 112 can be coupled to ground in some embodiments.

[0026]

[0028] The first electrode 108 can be coupled to a first conditioning circuit 128 that can control the ground path of the process chamber 100. The first conditioning circuit 128 can include a first electronic sensor 130 and a first electronic controller 134. The first electronic controller 134 can be or include a variable capacitor or other circuit element. The first conditioning circuit 128 can be or include one or more inductors 132. The first conditioning circuit 128 can be any circuit that allows for a variable or controllable impedance under the plasma conditions present in the process volume 120 during processing. In some embodiments as shown, the first conditioning circuit 128 can 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 can include a first inductor 132A. The second circuit leg can include a second inductor 132B coupled in series with the first electronic controller 134. The second inductor 132B can be disposed 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 can be a voltage or current sensor and can be coupled to the first electronic controller 134, which can allow for some closed loop control of the plasma conditions within the process volume 120.

[0027]

[0029] The second electrode 122 may be coupled to the substrate support 104. The second electrode 122 may be embedded in the substrate support 104 or coupled to a 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 arrangement of conductive elements. The second electrode 122 may be a conditioning electrode and may be coupled to a second conditioning circuit 136 by a conduit 146, such as a cable having a selected resistance, such as, for example, 50 ohms, disposed on a shaft 144 of the substrate support 104. The second conditioning circuit 136 may have 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 to the second electronic controller 140 to further control over the plasma conditions in the process volume 120.

[0028]

[0030] A third electrode 124, which may be a bias electrode and / or an electrostatic chucking electrode, may be coupled to the 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.

[0029]

[0031] The lid assembly 106 and substrate support 104 of FIG. 1 can be used with any processing chamber for plasma or thermal processing. In operation, the processing chamber 100 can provide real-time control of plasma conditions in the processing volume 120. The substrate 103 can be placed on the substrate support 104, and process gases can be flowed through the lid assembly 106 using the inlet 114 according to any desired flow plan. The gases can exit the processing chamber 100 through the outlet 152. Power can be coupled with the gas distributor 112 to establish a plasma in the processing volume 120. In some embodiments, the substrate can be subjected to an electrical bias using the third electrode 124.

[0030]

[0032] Upon energizing the plasma in the process 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. The electronic controllers 134, 140 can then be used to adjust the flow characteristics of the ground paths presented by the two adjustment circuits 128 and 136. Set points can be provided to the first adjustment circuit 128 and the second adjustment circuit 136 to provide independent control of the deposition rate and center-to-edge plasma density uniformity. In an embodiment where the electronic controllers can both be variable capacitors, the electronic sensor can adjust the variable capacitors to maximize the deposition rate and independently minimize the thickness non-uniformity.

[0031]

[0033] Each of the conditioning circuits 128, 136 may have a variable impedance that may be adjusted using the respective electronic controller 134, 140. If the electronic controller 134, 140 is a variable capacitor, the capacitance range of each of the variable capacitors and the inductance 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 capacitance range of each variable capacitor may be minimum. Thus, when the capacitance of the first electronic controller 134 is minimum or maximum, the impedance of the first conditioning circuit 128 may be high, resulting in a plasma shape with minimum aerial or lateral reach above the substrate support. When the capacitance of the first electronic controller 134 approaches a value that minimizes the impedance of the first conditioning circuit 128, the aerial reach of the plasma is maximized, effectively covering the entire working area of ​​the substrate support 104. As the capacitance of the first electronic controller 134 deviates from the minimum impedance setting, the plasma shape may shrink from the chamber walls and the aerial coverage of the substrate support may decrease. The second electronic controller 140 may have a similar effect, increasing and decreasing the aerial coverage of the plasma above the substrate support as the capacitance of the second electronic controller 140 may change.

[0032]

[0034] The electronic sensors 130, 138 may be used to regulate the respective circuits 128, 136 in a closed loop. Depending on the sensor type used, a current or voltage set point may be built into each sensor, which may be equipped with control software that determines adjustments to the respective electronic controllers 134, 140 to minimize deviations from the set point. As a result, a certain plasma shape may be selected and dynamically controlled during processing. Although the above discussion is based on the electronic controllers 134, 140 being variable capacitors, it should be understood that any electronic components with tunable characteristics may be used to provide tunable impedance to the regulation circuits 128 and 136.

[0033]

[0035] 2 illustrates exemplary operations in a processing method 200 according to some embodiments of the present technique. The method can be performed in a variety of processing chambers, including the processing chamber 100 described above. The method 200 can include a number of optional operations that may or may not be specifically associated with some embodiments of the method according to the present technique. For example, many of the operations are described to provide a broader scope of structure formation, but are not critical to the present technique or may be performed by alternative methodologies as will be readily understood.

[0034]

[0036] Method 200 may include a processing method that may include several operations to prepare the chamber for processing, form a hard mask film, or other deposition operations. The method may include optional operations before the start of method 200, or the method may include additional operations. For example, method 200 may include operations performed in a different order than those illustrated. As described, multiple iterations may be performed, and in some embodiments, at optional operation 205, the method may be performed following a prior chamber clean. An exemplary cleaning operation may utilize plasma-enhanced halogen-containing or other etchant precursors. While beneficial for material removal, halogen materials may interact with aluminum chamber components as described above, and in one non-limiting example, utilizing a fluorine precursor may result in the formation and / or redeposition of aluminum fluoride around the processing area of ​​the chamber.

[0035]

[0037] In some embodiments, the method 200 can include plasma treatment in optional operation 210, which can include plasma-enhanced precursors that can be delivered from a remote plasma unit or deployed in situ at the processing region. The precursors can include hydrogen-containing precursors, oxygen-containing precursors, or any other precursors that can be used or facilitate the conversion of aluminum fluoride back to aluminum or aluminum oxide. As one non-limiting example, nitrous oxide, or other oxygen-containing precursors such as oxygen, can be delivered to the processing region and a plasma can be generated. The oxygen-containing plasma effluents formed can convert aluminum fluoride to aluminum oxide, which can remain more stable on the chamber surfaces. Additionally, the precursors can remove aluminum fluoride material from the chamber.

[0036]

[0038] A seasoning or treatment film can then be deployed in the chamber in optional operation 215. For example, an oxide material such as silicon oxide can be formed on the surfaces of the processing chamber, such as a region within the processing region, including the exposed surfaces of the processing volume 120 described above. The region can be an internal plasma region, which can be at least partially defined by a number of chamber components. For example, the chamber sidewalls, showerhead or faceplate, and pedestal can all be included in or at least partially defined as aspects of the processing region. A plasma can be formed in the processing region, and a precursor for depositing silicon oxide can be introduced. A film of silicon oxide can be formed to a first thickness over the chamber surfaces, which can ensure complete coating of the surfaces.

[0037]

[0039] After forming the silicon oxide surface, the method 200 may include forming a nitride material, such as silicon nitride. The silicon nitride may be formed to a second thickness on the silicon oxide. The components in the processing chamber may be aluminum or may include aluminum. Silicon nitride may not easily deposit or adhere to aluminum surfaces. However, silicon nitride may provide a film that can withstand etching under processing conditions where some film deposition may occur. For example, as described further below, tungsten and carbon films may be produced, and the tungsten-containing precursor may include a halide tungsten precursor. The in situ plasma may dissociate the precursor forming halogen emissions that may react with unprotected aluminum. Silicon nitride may capture fluorine and provide a better adhesion surface for the tungsten and carbon film, which may reduce falling particles on the substrate. Silicon oxide may adhere better to aluminum, but may not provide sufficient adhesion to the tungsten and carbon film and may attract additional falling particles to the substrate.

[0038]

[0040] The first layer of silicon oxide may be of a different thickness than the second layer of silicon nitride, since the first and second layers provide different advantages. For example, in some embodiments, the role of the silicon oxide may be to provide a complete coating over the entire chamber surface. Thus, the first thickness may be limited to adequately coat the chamber surface. Thus, the first layer of oxide may be characterized by a first thickness of about 50 nm or less, and may be characterized by a first thickness of about 40 nm or less, about 30 nm or less, about 20 nm or less, 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, or less. The first layer may be characterized by a thickness of about 1 nm or more, which may ensure complete coverage of the interior surface. If gaps are formed in the area, the silicon nitride may not adhere easily and aluminum exposure may occur.

[0039]

[0041] In some embodiments, the role of silicon nitride may be to provide a resistant coating during plasma processing. Thus, the second thickness may be greater than the first thickness in some embodiments, which may provide improved resistance, gettering, and protection from plasma effluents. Thus, for example, the second layer of nitride may be characterized by a second thickness of about 50 nm or more, and may be characterized by a thickness of about 60 nm or more, about 70 nm or more, about 80 nm or more, about 90 nm or more, about 100 nm or more, about 120 nm or more, about 140 nm or more, about 160 nm or more, about 180 nm or more, about 200 nm or more, or more.

[0040]

[0042] Following the formation of the coating or seasoning, the substrate may be placed in a processing region in optional operation 220. For example, the substrate support may be coated with oxides and nitrides during the method, and the substrate may be placed on the first and second layers of material on the substrate support. For example, the substrate may be placed on a silicon nitride material formed on the substrate support. Exemplary substrates may include any number of materials including silicon, silicon germanium, as well as any number of preformed films including oxides, nitrides, or any other materials that may be formed on a semiconductor substrate.

[0041]

[0043] In some embodiments, the substrate may be or include silicon, although additional materials may be used. In operation 225, the surface of the substrate may be treated to facilitate the initiation of a subsequent deposition operation. The treatment of the substrate surface may be performed with one or more precursors, and may include, for example, a hydrogen-containing precursor, a nitrogen-containing precursor, and / or other precursors. A plasma may be formed from the precursor, which may create hydrogen termination on the surface of the substrate, which may facilitate the incorporation of subsequent materials. Interaction of the hydrogen radicals may create dangling bonds or other ligand terminations on the surface, which may increase interaction with the precursor. In operation 230, a tungsten-containing precursor may be delivered to the processing region to contact the substrate. For example, a tungsten-containing precursor, such as tungsten hexafluoride, may be delivered to interact with dangling bonds on the surface of the substrate. This may form a tungsten layer on the surface of the substrate, which may be about 5 Å or less in thickness in some embodiments.

[0042]

[0044] In some embodiments, the tungsten-containing precursor may have a regulated delivery during formation. The tungsten-containing precursor may be delivered after the plasma is terminated for processing, and in some embodiments, may be delivered as an unexcited precursor. Furthermore, the tungsten-containing precursor may be delivered during or at least partially during a processing operation, in some embodiments. For example, an initial flow rate of the tungsten-containing precursor may be provided during a processing operation and slowly ramped for a period of time, followed by extinguishing the plasma. By slowly ramping the flow rate during plasma processing, reduced fluorine radical production may occur, which in some embodiments may limit the incorporation of fluorine into the initiation layer.

[0043]

[0045] In operation 235, a subsequent processing operation may be performed on the initiating layer. The processing may include materials similar to or different from the processing performed in operation 225. For example, a hydrogen-containing precursor and / or a nitrogen-containing precursor may be delivered to the substrate processing region and a plasma may be generated from the precursor. The plasma effluent may contact and / or impinge on the tungsten-containing initiating layer. This interaction may incorporate nitrogen within the tungsten material and may also generate nitrogen vacancies from further impingement. The generated tungsten and nitrogen layer may act as a barrier layer for subsequent depositions and may provide nucleation sites for further depositions.

[0044]

[0046] In some embodiments, the formation of the initiation layer can be repeated with any number of cycles of processing. For example, a tungsten-containing precursor can be flowed again into the processing region to further develop a tungsten and nitrogen layer. Furthermore, by repeating the method, fluorine and / or tungsten can be incorporated into pores in the structure. This can limit the subsequent diffusion of fluorine that is subsequently delivered during bulk film formation. After one or more cycles of initiation layer development, the method 200 can form a bulk layer of tungsten and carbon film.

[0045]

[0047] In operation 240, a plasma may be formed from a tungsten-containing precursor and a hydrogen-containing precursor. The tungsten-containing precursor may be or may include tungsten hexafluoride or any other tungsten-containing material, and the carbon-containing precursor may include several carbon-containing precursors. For example, the carbon-containing precursor may be or may include any alkane, alkene, or any other carbon-containing material. The precursor may include a carbon-hydrogen-containing precursor, which may include any amount of carbon and hydrogen bonds. In some embodiments, the carbon-containing precursor may consist of carbon-carbon bonds and carbon-hydrogen bonds.

[0046]

[0048] As previously mentioned, the bulk film or hard mask may be formed with limited hydrogen content to facilitate grain size reduction of the film. The carbon-containing precursor may include hydrogen, but in some embodiments, no additional hydrogen source may be provided. For example, diatomic hydrogen may be excluded from the delivered precursor. An inert precursor or carrier gas may be provided with the tungsten-containing precursor and the carbon-containing precursor, but other chemically reactive precursors may be delivered with the precursor in some embodiments. By limiting the hydrogen provided to the plasma to that contained in the carbon-containing precursor, the atomic ratio of hydrogen delivered to form the plasma may be lower than if additional hydrogen gas is provided. For example, the atomic ratio of hydrogen to tungsten in the delivered precursor may be about 8:1 or less, and may be about 7:1 or less, about 6:1 or less, about 5:1 or less, about 4:1 or less, about 3:1 or less, about 2:1 or less, or less, in embodiments. In one non-limiting example, the carbon-containing precursor may be propene, and the ratio of hydrogen to tungsten may be 6:1 for the precursor delivered to form the plasma. In operation 245, the plasma effluents may be deposited on an initiation layer, such as overlying the substrate, to form a hardmask film, which may be or include a carbon-containing or tungsten-containing hardmask film.

[0047]

[0049] Incorporating additional hydrogen into the delivered plasma generating precursor can affect the properties of the plasma. For example, hydrogen can often be a large portion of the delivered precursor and can generate a large number of hydrogen radicals within the plasma. The plasma can at least partially dissociate the tungsten-containing precursor, but the hydrogen radicals can also increase chemical interactions with the tungsten material, such as chemically removing fluorine from the precursor. However, the amount of hydrogen can also reduce the deposition rate by blocking nucleation sites and removing the material being deposited.

[0048]

[0050] To improve the chemical interaction reduced by removing hydrogen delivery, some embodiments of the present technology can increase the amount of tungsten-containing precursor delivered. For example, maintaining the amount of tungsten delivery without providing a hydrogen material may reduce the incorporation of tungsten into the film produced, since the reduced amount of tungsten radicals and emissions may deposit or interact with the substrate surface. To increase the amount of tungsten incorporated at the surface and maintain the proportion of tungsten in the film, the flow rate of tungsten can be maintained at about 100 sccm or more, about 150 sccm or more, about 200 sccm or more, about 250 sccm or more, about 300 sccm or more, or higher. Furthermore, in some embodiments, the flow rate of the tungsten-containing precursor can be maintained higher than the carbon-containing precursor in some embodiments, although the atomic flow rate of the carbon-containing precursor can be higher. For example, for the exemplary precursors tungsten fluoride and propene, the volumetric flow ratio of the tungsten-containing precursor to the carbon-containing precursor can be about 1:1 or greater, and can be about 1.05:1 or greater, about 1.10:1 or greater, about 1.15:1 or greater, about 1.20:1 or greater, about 1.25:1 or greater, about 1.30:1 or greater, about 1.35:1 or greater, about 1.40:1 or greater, or higher.

[0049]

[0051] This allows the percentage of tungsten in the produced film to be maintained at about 10% or more, and the percentage of tungsten in the produced film to be maintained at about 12% or more, about 13% or more, about 14% or more, about 15% or more, about 16% or more, about 17% or more, about 18% or more, about 19% or more, about 20% or more, about 21% or more, about 22% or more, about 23% or more, about 24% or more, about 25% or more, about 26% or more, about 27% or more, about 28% or more, about 29% or more, or more. Additionally, by eliminating the delivery of diatomic hydrogen, deposition rates can be increased for the bulk film. For example, compared to films formed utilizing diatomic hydrogen with a deposition precursor, the present techniques can provide deposition rates that are about 1.2 times or more faster, about 1.4 times or more, about 1.6 times or more, about 1.8 times or more, about 2.0 times or more, about 2.2 times or more, about 2.4 times or more, about 2.6 times or more, about 2.8 times or more, or more.

[0050]

[0052] Reducing hydrogen incorporation can provide additional nucleation sites on the substrate for tungsten incorporation. Increasing the number of nucleation sites can reduce the general area of ​​each site, thereby reducing the area for grain growth in the film. By reducing or eliminating the hydrogen content in the plasma precursor, the average grain size of the formed film can be about 2.5 nm or less, and in some embodiments, can be about 2.4 nm or less, about 2.3 nm or less, about 2.2 nm or less, about 2.1 nm or less, about 2.0 nm or less, about 1.9 nm or less, about 1.8 nm or less, about 1.7 nm or less, about 1.6 nm or less, about 1.5 nm or less, about 1.4 nm or less, about 1.3 nm or less, about 1.2 nm or less, or less. These smaller grain sizes can increase the uniformity of the critical dimension profile during the formation of high aspect ratio features or features characterized by reduced critical dimension profiles.

[0051]

[0053] After the deposition process is completed, such as by forming a bulk film to a desired thickness, the substrate may be removed from the processing region in optional operation 250. Residual carbon material or tungsten and carbon material from the process may collect on the surface of the silicon nitride seasoning or on exposed chamber surfaces. In other processes, an alternative precursor may be placed on the surface protected by the silicon nitride. Thus, in some embodiments, a chamber clean may be performed in optional operation 255, which may be similar or identical to the clean performed in operation 205 described above. For example, performing a chamber clean in optional operation 255 may resume the method 200 in some embodiments for an additional substrate. The chamber clean may utilize a halogen-containing precursor, which may be plasma enhanced in the processing region to facilitate removal of residual materials. The clean process may remove some or all aspects of the residual tungsten and carbon material, and in some embodiments, may remove some or all of the layers of the seasoning material.

[0052]

[0054] The process can then be repeated for subsequent substrates. In some embodiments, the complete method may not be repeated. For example, in some processing operations, the silicon nitride material may not be completely removed throughout the processing area, and therefore the silicon oxide material may remain intact. As a result, in some embodiments, the method may include forming or reforming or repairing the silicon nitride film, such as by starting the method 200 at some intermediate operation in the process. The method may begin at any of the described operations in some embodiments. Removing diatomic hydrogen and other hydrogen sources from the bulk deposition of the film may provide an improved grain structure over conventional techniques while maintaining or improving optical or other film properties. To accommodate fluorine diffusion and other aspects of the produced film, an initiation layer or barrier layer may be incorporated at the interface between the bulk film and the underlying substrate.

[0053]

[0055] In the foregoing description, for purposes of explanation, numerous details are set forth in order to provide an understanding of various embodiments of the present technology. However, it will be apparent to one skilled in the art that particular embodiments may be practiced without some of these details, or with additional details.

[0054]

[0056] Although several embodiments have been disclosed, those skilled in the art will recognize that various modifications, alternative constructions, and equivalents may be used without departing from the spirit of the embodiments. Moreover, some well-known processes and elements have not been described to avoid unnecessarily obscuring the technology. Thus, the above description should not be construed as limiting the scope of the technology.

[0055]

[0057] Where a range of values ​​is presented, unless the context clearly dictates otherwise, it is understood that each intervening value between the upper and lower limits of that range is also specifically disclosed to the smallest unit of the unit of the lower limit. Any narrower range between any stated or unstated intervening value in a stated range, as well as any other stated or intervening value in that stated range, are also encompassed. The upper and lower limits of these smaller ranges may be individually included or excluded in the range, and each range in which either, neither, or both limits are included in the narrower range is also encompassed within the technology, subject to the specifically excluded limit in the stated range. Where a stated range includes one or both of the limits, ranges excluding either or both of the included limits are also included.

[0056]

[0058] As used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly indicates otherwise. Thus, for example, reference to "a precursor" includes a reference to a plurality of such precursors, reference to "a layer" includes a reference to one or more layers and equivalents thereof known to those skilled in the art, and so forth.

[0057]

[0059] Additionally, the terms "comprise(s)", "comprising", "contain(s)", "containing", "include(s)", and "including", when used in this specification and claims, are intended to specify the presence of stated features, integers, components, or steps, but do not exclude the presence or addition of one or more other features, integers, components, operations, acts, or groups.

Claims

1. treating a surface of a substrate disposed within a processing region of a semiconductor processing chamber with a hydrogen-containing precursor; contacting the substrate with a tungsten-containing precursor; forming an initiation layer comprising tungsten on the substrate; treating the initiation layer with a hydrogen-containing precursor; forming a plasma of the tungsten-containing precursor and the carbon-containing precursor, wherein hydrogen in the plasma is limited to hydrogen contained in the carbon-containing precursor; and forming a tungsten-containing hardmask layer over the initiation layer; Including, 13. A semiconductor processing method, wherein an atomic ratio of hydrogen to tungsten in the combination of the carbon-containing precursor and the tungsten-containing precursor is about 8:1 or less.

2. Treating the surface of the substrate includes: forming a plasma of the hydrogen-containing precursor; and 10. The semiconductor processing method of claim 1, comprising contacting said surface of said substrate with effluents of said plasma to produce a hydrogen termination.

3. 2. The semiconductor processing method of claim 1 , wherein the tungsten-containing precursor is delivered to said contacting while said treating said surface of said substrate is being performed.

4. 4. The semiconductor processing method of claim 3, wherein a flow rate of the tungsten-containing precursor is increased while the tungsten-containing precursor is being delivered.

5. Treating the initiation layer includes: forming a plasma of the hydrogen-containing precursor; and contacting said initiation layer with effluent of said plasma; 2. The semiconductor processing method of claim 1, comprising:

6. The semiconductor processing method of claim 5 , wherein the plasma further comprises a nitrogen-containing precursor.

7. 7. The semiconductor processing method of claim 6, wherein the hydrogen-containing precursor comprises diatomic hydrogen and the nitrogen-containing precursor comprises diatomic nitrogen.

8. 10. The semiconductor processing method of claim 1, wherein the tungsten-containing precursor comprises tungsten hexafluoride and the carbon-containing precursor comprises propene.

9. 10. The semiconductor processing method of claim 8, wherein diatomic hydrogen is excluded from the semiconductor processing chamber during forming the plasma of the tungsten-containing precursor and the carbon-containing precursor.

10. 10. The semiconductor processing method of claim 1, further comprising forming a seasoning layer comprising a silicon-containing material on an exposed surface of said processing region of said semiconductor processing chamber.

11. forming a seasoning layer on an exposed surface of a processing region of a semiconductor processing chamber; treating a surface of a substrate disposed in the processing region of the semiconductor processing chamber with a hydrogen-containing precursor; contacting the substrate with a tungsten-containing precursor; forming an initiation layer comprising tungsten on the substrate disposed in the processing region of the semiconductor processing chamber; treating the initiation layer with a hydrogen-containing precursor; forming a plasma of the tungsten-containing precursor and the carbon-containing precursor, wherein hydrogen in the plasma is limited to hydrogen contained in the carbon-containing precursor, and an atomic ratio of hydrogen in the precursor delivered to form the plasma to tungsten in the precursor delivered to form the plasma is less than 8:1; and forming a tungsten-containing hardmask layer over the initiation layer; A semiconductor processing method comprising:

12. The semiconductor processing method of claim 11 , wherein the seasoning layer comprises silicon oxide and silicon nitride.

13. Forming the initiation layer comprises: forming a plasma of the hydrogen-containing precursor; contacting the surface of the substrate with effluent of the plasma to produce a hydrogen termination; and flowing the tungsten-containing precursor into the processing region and contacting the surface of the substrate; The semiconductor processing method of claim 11 , comprising:

14. 14. The semiconductor processing method of claim 13, wherein the tungsten-containing precursor is not excited while being flowed into contact with the surface of the substrate.

15. forming a plasma of the hydrogen-containing precursor; and contacting said initiation layer with effluent of said plasma; The semiconductor processing method of claim 11 further comprising:

16. 12. The semiconductor processing method of claim 11, wherein the tungsten-containing precursor comprises tungsten hexafluoride and the carbon-containing precursor comprises propylene.

17. 20. The semiconductor processing method of claim 16, wherein diatomic hydrogen is excluded from the semiconductor processing chamber during forming the plasma of the tungsten-containing precursor and the carbon-containing precursor.

18. forming a seasoning layer on an exposed surface of a processing region of a semiconductor processing chamber; treating a surface of a substrate disposed in the processing region of the semiconductor processing chamber with a hydrogen-containing precursor; contacting the substrate with a tungsten-containing precursor; forming an initiation layer comprising tungsten on the substrate; treating the initiation layer with a hydrogen-containing precursor; forming a plasma of the tungsten-containing precursor and the carbon-containing precursor, wherein hydrogen in the plasma is limited to hydrogen contained in the carbon-containing precursor, and wherein an atomic ratio of hydrogen to tungsten in the combination of the carbon-containing precursor and the tungsten-containing precursor is about 8:1 or less; and forming a tungsten-containing hardmask layer over the initiation layer; A semiconductor processing method comprising:

19. Removing the substrate from the semiconductor processing chamber; and performing a chamber clean process in the processing region of the semiconductor processing chamber.

20. The semiconductor processing method of claim 18 further comprising:

20. 20. The semiconductor processing method of claim 19, further comprising forming a plasma of an oxygen-containing precursor in the processing region of the semiconductor processing chamber.

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