Systems and methods for depositing low-k dielectric films

Abstract

Embodiments are described that include a semiconductor processing method for forming a low-k film on a semiconductor substrate. The processing method may include flowing one or more deposition precursors to a semiconductor processing system, wherein the one or more deposition precursors include a silicon-containing precursor. The silicon-containing precursor may include a carbon chain. The method may include generating a deposition plasma from one or more deposition precursors. The method may include depositing a silicon and carbon containing material on a substrate from a plasma effluent of a deposition plasma. The deposited silicon and carbon containing material may be characterized by a dielectric constant of less than or about 3.0.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. patent application No. 17 / 896,753, filed on August 26, 2022, entitled “SYSTEMS AND METHODS FOR DEPOSITING LOW-K DIELECTRIC FILMS,” which is incorporated herein by reference in its entirety. Technical Field

[0002] The present technology relates to deposition processes and chambers. More specifically, the present technology relates to methods of producing low-κ films that can be produced without the use of UV treatment. Background Art

[0003] Integrated circuits are made possible by processes that produce intricately patterned layers of material on a substrate surface. Producing patterned materials on a substrate requires controlled methods for forming and removing materials. Material properties can affect the operation of the device and can also affect the way films are removed relative to each other. Plasma enhanced deposition can produce films with certain properties. In order to provide suitable properties, the formation of many films requires additional processing to adjust or enhance the material properties of the film.

[0004] Therefore, there is a need for improved systems and methods that can be used to produce high quality devices and structures. The present technology can meet these and other needs. Summary of the invention

[0005] Embodiments of the present technology are described that encompass semiconductor processing methods for forming low-κ films on semiconductor substrates. The processing method may flow one or more deposition precursors to a semiconductor processing system, wherein the one or more deposition precursors include a silicon-containing precursor. The silicon-containing precursor may include a carbon chain. The method may include: generating a deposition plasma from the one or more deposition precursors. The method may include: depositing a silicon- and carbon-containing material on a substrate from plasma effluents of the deposition plasma. The deposited silicon- and carbon-containing material may be characterized by a dielectric constant of less than or about 3.0.

[0006] In some embodiments, the silicon-containing precursor may be characterized by Formula 1: R may be hydrogen, alkyl, alkoxy, olefin, alkyne, acrylate, halide, NO2, NH2, CN, NCO, NCS or C=OR, and n may be between 1 and 12. The silicon-containing precursor may include a propane chain, a butane chain, a hexane chain or a heptane chain. The deposition precursor may further include: molecular oxygen (O2), diatomic hydrogen (H2), or a combination of the two. Generating a deposition plasma from one or more deposition precursors may include: forming a deposition plasma in a remote plasma unit. The silicon-and-carbon-containing material may be characterized by a methyl incorporation content greater than or about 2.0 atomic percent. The silicon-and-carbon-containing material may be characterized by a Young's modulus greater than or about 3 GPa. The silicon-and-carbon-containing material may be characterized by a hardness greater than or about 0.5 GPa.

[0007] Some embodiments of the present technology encompass semiconductor processing methods. The methods may include flowing a deposition precursor to a semiconductor processing system. The deposition precursor may include a silicon-containing precursor and a carbon-containing precursor. The carbon-containing precursor may be a chain compound. The methods may include generating a deposition plasma from one or more deposition precursors. The methods may include depositing a silicon- and carbon-containing material on a substrate from plasma effluents of the deposition plasma. The deposited silicon- and carbon-containing material may be characterized by a dielectric constant of less than or about 3.0.

[0008] In some embodiments, the temperature during the generation of the deposition plasma may be maintained at less than or about 420° C. The deposition precursor may further include molecular oxygen (O 2 ). The deposition precursor may further include diatomic hydrogen (H 2 ). Generating the deposition plasma from the one or more deposition precursors may include forming the deposition plasma in a remote plasma unit. The deposited silicon- and carbon-containing material may be characterized by a Young's modulus greater than or about 5 GPa.

[0009] Some embodiments of the present technology encompass semiconductor processing methods. The methods may include flowing a deposition precursor into a substrate processing region of a semiconductor process chamber. The deposition precursor may include a silicon-containing precursor. The deposition precursor may include a carbon chain. The methods may include generating a deposition plasma from the deposition precursor within the substrate processing region. The methods may include depositing a silicon- and carbon-containing material on a substrate from plasma effluents of the deposition plasma. The deposited silicon- and carbon-containing material may be characterized by a dielectric constant of less than or about 3.0. The deposited silicon- and carbon-containing material may be characterized by a Young's modulus of greater than or about 4.0 GPa.

[0010] In some embodiments, the silicon-containing precursor may include a carbon chain of a deposition precursor. The deposition precursor may further include: at least one carrier gas including helium or nitrogen (N2). Generating the deposition plasma may include: applying an RF power of less than or about 500W. The flow rate of the deposition precursor may be characterized by less than or about 500mg / min. The method may include: performing a post-deposition treatment on the silicon- and carbon-containing material. The post-deposition treatment may include UV curing or thermal annealing.

[0011] Such techniques can provide many benefits relative to conventional processing methods. For example, the use of deposition precursors including carbon chains can increase the presence of closed nanopores within the deposited low-κ material. The increase in the amount of closed nanopores can increase the carbon level in the material without reducing its mechanical properties, such as Young's modulus and hardness. In addition to forming closed nanopores, the carbon chain can also increase the level of carbon in these low-κ films, reducing the dielectric constant (κ value) of the film to less than or about 3.0 without simultaneously reducing its mechanical stability. Further, increasing the presence of closed nanopores can prevent or reduce etchants (such as wet etchants) from passing through open holes in the material to reach other layers or regions of the structure and causing damage. Embodiments of the present technology also include processing methods in which the deposition of low-κ materials can be performed at a temperature greater than or about 420°C. The increase in deposition temperature also increases the amount of Si-C crosslinking in the low-κ material. In further embodiments of the present technology, the deposited low-κ material can be characterized by a low κ value and high mechanical stability without undergoing post-deposition, ultraviolet treatment that adds additional time and complexity to the processing method. These and other embodiments, as well as their numerous advantages and features, are described in more detail in conjunction with the following description and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] A further understanding of the nature and advantages of the technology disclosed herein may be obtained by reference to the remainder of the specification and the accompanying drawings.

[0013] Figure 1 A top plan view of an exemplary processing system is shown in accordance with some embodiments of the present technology.

[0014] Figure 2 A schematic cross-sectional diagram is shown of an exemplary plasma system according to some embodiments of the present technology.

[0015] Figure 3 Operations of an exemplary method of semiconductor processing in accordance with some embodiments of the present technology are illustrated.

[0016] Several of the drawings disclosed herein are provided as schematic diagrams. It should be understood that the drawings are for illustration purposes only and should not be considered to be drawn to scale unless specifically stated to be drawn to scale. Furthermore, as schematic diagrams, the drawings are provided to aid understanding and may not include all aspects or information compared to realistic representations and may include exaggerated material for illustration purposes.

[0017] In the accompanying drawings, similar components and / or features may have the same reference numeral. Further, various components of the same type may be distinguished by appending a letter after the reference numeral that distinguishes the similar components. If only the first reference numeral is used in the specification, the description applies to any of the similar components having the same first reference numeral, regardless of the letter. DETAILED DESCRIPTION

[0018] During back-end-of-line (BEOL) semiconductor processing, low-κ films can perform a variety of functions in the fabrication of metallization layers in integrated circuits. These functions can include incorporating electrically insulating low-κ films between conductive metal-containing structures such as interconnects, contact holes and vias, and other structures. They can also include partial removal of low-κ films after metal structures are formed. One common removal process in BEOL processing is chemical mechanical polishing (CMP), which uses a combination of chemical etching and physical grinding to remove low-κ materials from the substrate surface.

[0019] Low-κ films used in BEOL processing should have a lower dielectric constant (κ value) relative to undoped silicon oxide and high mechanical stability to prevent cracking during metal-containing structure formation and removal by CMP. Unfortunately, these qualities are often under strain in low-κ films made from silicon- and carbon-containing materials. In many cases, higher carbon content in the material may simultaneously reduce the κ value and reduce the mechanical stability of the film, which is characterized by lower Young's modulus and lower hardness, as well as other mechanical properties of the film.

[0020] One way to enhance the mechanical stability of low-κ films is to treat the deposited film with ultraviolet light (i.e., UV treatment / curing operation). Unfortunately, these UV treatment operations typically involve transferring the substrate from the low-κ film deposition chamber to the UV treatment chamber, which increases the time and complexity of the overall low-κ film formation operation. In most cases, UV light can only penetrate the low-κ material to a depth of a few angstroms, so a fully treated low-κ film requires shuttling the substrate between the deposition chamber and the treatment chamber several times to complete a low-κ film with a thickness of tens to hundreds of angstroms. Multiple deposition and treatment operations can significantly reduce the wafer throughput in the semiconductor manufacturing process.

[0021] The present technology can overcome these problems by including embodiments of semiconductor processing methods that form low-κ films with good mechanical stability. In embodiments, these low-κ films can be characterized by a high Young's modulus (e.g., greater than or about 5.0 GPa) and a high hardness (e.g., greater than or about 0.2 GPa). By performing deposition at high temperatures with a specific deposition precursor comprising one or more carbon chains, the film can be characterized by an increased level of closed nanopores within the film. This can overcome the natural tendency of the modulus, hardness, and other characteristics of the mechanical stability of the film to decrease as the dielectric constant decreases, while also reducing the number of operations required during processing. Specifically, the present technology can post-treat the film to enhance hardness without utilizing subsequent post-deposition processing (including UV exposure, plasma treatment, or other processing operations).

[0022] Although the remainder of the disclosure will routinely identify specific deposition processes using the disclosed techniques, it will be readily appreciated that the systems and methods are equally applicable to other deposition and cleaning chambers, and processes that may occur in the chambers. Therefore, the techniques should not be viewed as limited to techniques for use with only these specific deposition processes or chambers. Before describing additional details of embodiments according to the present technology, the present disclosure will discuss possible systems and chambers that may be used to perform deposition processes according to embodiments of the present technology.

[0023] Figure 1 A top plan view of one embodiment of a processing system 100 of deposition, etching, baking and curing chambers according to an embodiment is shown. In the figure, a pair of front-opening unified chambers 102 supply substrates of various sizes, which are received by a robot 104 and placed into a low pressure holding area 106, and then placed into one of the substrate process chambers 108a to 108f, which are positioned in series blocks 109a to 109c. A second robot 110 can be used to transfer substrate wafers from the holding area 106 to the substrate process chambers 108a to 108f and back. Each substrate process chamber 108a to 108f can be equipped to perform a number of substrate processing operations, including the formation of stacks of semiconductor materials described herein, as well as plasma enhanced chemical vapor deposition, atomic layer deposition, physical vapor deposition, etching, pre-cleaning, degassing, orientation, and other substrate processes (including annealing, ashing, etc.).

[0024] The substrate process chambers 108a to 108f may include one or more system components for depositing, annealing, curing and / or etching dielectric films or other films on the substrate. In one configuration, two pairs of process chambers (e.g., 108c-108d and 108e-108f) in the process chambers may be used to deposit dielectric materials on the substrate, and a third pair of process chambers (e.g., 108a-108b) in the process chambers may be used to etch the deposited dielectric. In another configuration, all three pairs of chambers (e.g., 108a to 108f) may be configured to deposit alternating stacks of dielectric films on the substrate. Any one or more of the processes described herein may be performed in a chamber separate from the manufacturing system as shown in different embodiments. It will be understood that the system 100 may contemplate additional configurations of deposition, etching, annealing, and curing chambers for dielectric films.

[0025] Figure 2 A schematic cross-sectional view of an exemplary plasma system 200 according to some embodiments of the present technology is shown. The plasma system 200 may illustrate a pair of process chambers 108 that may be installed in one or more tandem blocks 109 described above and may include a lid stack component according to embodiments of the present technology and may be further explained as follows. The plasma system 200 may generally include a chamber body 202 having a sidewall 212, a bottom wall 216, and an inner sidewall 201 that define a pair of processing regions 220A and 220B. Each of the processing regions 220A-220B may be configured in a similar manner, and each processing region 220A-220B may include the same components.

[0026] For example, the processing region 220B (components of which may also be included in the processing region 220A) may include a pedestal 228 disposed in the processing region through a passage 222 formed in the bottom wall 216 in the plasma system 200. The pedestal 228 may provide a heater adapted to support a substrate 229 on an exposed surface of the pedestal, such as a body portion. The pedestal 228 may include a heating element 232, such as a resistive heating element, which may heat the substrate and control the substrate temperature at a desired process temperature. The pedestal 228 may also be heated by a remote heating element, such as a bulb assembly or any other heating device.

[0027] The body of the base 228 can be coupled to the shaft 226 via the flange 233. The shaft 226 can electrically couple the base 228 to the power output or power box 203. The power box 203 can include a drive system that controls the lifting and movement of the base 228 within the processing area 220B. The shaft 226 can also include an electrical power interface to provide power to the base 228. The power box 203 can also include an interface for power and temperature indicators, such as a thermal coupling interface. The shaft 226 can include a base assembly 238 suitable for removably coupling the power box 203. A circumferential ring 235 is shown above the power box 203. In some embodiments, the circumferential ring 235 can be a shoulder suitable for acting as a mechanical stop, or a platform configured to provide a mechanical interface between the base assembly 238 and the upper surface of the power box 203.

[0028] A rod 230 may be included that passes through a passage 224 formed in the bottom wall 216 of the processing region 220B and may be used to position a substrate lift pin 261 disposed through the body of the pedestal 228. The substrate lift pin 261 may selectively separate the substrate 229 from the pedestal to facilitate exchanging the substrate 229 with a robot that is used to transfer the substrate 229 into and out of the processing region 220B through the substrate transfer port 260.

[0029] The chamber lid 204 can be coupled to a top portion of the chamber body 202. The lid 204 can house one or more precursor dispensing systems 208 coupled to the lid 204. The precursor dispensing system 208 can include a precursor inlet passage 240 that can deliver reactants and cleaning precursors to the processing region 220B through a dual channel showerhead 218. The dual channel showerhead 218 can include an annular base plate 248 having a baffle plate 244 disposed in the middle of a face plate 246. A radio frequency ("RF") source 265 can be coupled to the dual channel showerhead 218, and the RF source 265 can provide power to the dual channel showerhead 218 to facilitate generating a plasma region between the face plate 246 and the pedestal 228 of the dual channel showerhead 218. The dual channel showerhead 218 and / or the faceplate 246 may include one or more openings to allow precursors to flow from the precursor distribution system 208 to the processing regions 220A and / or 220B. In some embodiments, the openings may include at least one of a straight opening and a conical opening. In some embodiments, the RF source may be coupled to other portions of the chamber body 202, such as the pedestal 228, to facilitate plasma generation. A dielectric insulator 258 may be disposed between the lid 204 and the dual channel showerhead 218 to prevent RF power from being conducted to the lid 204. A shadow ring 206 may be disposed on the periphery of the pedestal 228, the shadow ring 206 engaging the pedestal 228.

[0030] An optional cooling channel 247 may be formed in the annular base plate 248 of the precursor distribution system 208 to cool the annular base plate 248 during operation. A heat transfer fluid such as water, glycol, gas, etc. may be circulated through the cooling channel 247 so that the base plate 248 can be maintained at a predetermined temperature. The liner assembly 227 may be disposed in the processing region 220B adjacent to the sidewalls 201, 212 of the chamber body 202 to prevent the sidewalls 201, 212 from being exposed to the processing environment in the processing region 220B. The liner assembly 227 may include a circumferential pumping chamber 225 to which a pumping system 264 may be coupled, the pumping system 264 being configured to exhaust gases and byproducts from the processing region 220B and control the pressure in the processing region 220B. A plurality of exhaust ports 231 may be formed on the liner assembly 227. The exhaust ports 231 may be configured to allow gases to flow from the processing region 220B to the circumferential pumping chamber 225 in a manner that facilitates processing within the system 200.

[0031] Figure 3 Operations of an exemplary method 300 of semiconductor processing according to some embodiments of the present technology are shown. The method can be performed in a variety of process chambers, including the processing system 200 described above, as well as any other chamber in which plasma deposition can be performed. The method 300 may include several optional operations that may or may not be specifically related to some embodiments of the method according to the present technology.

[0032] Method 300 may include a plasma enhanced chemical vapor deposition (PECVD) processing operation to form a deposited low-κ film having high mechanical stability. Compared to conventional methods, these deposited low-κ films do not require post-deposition processing such as UK curing to improve the mechanical stability of the film. Although post-deposition processing may not be required, in some embodiments, the processing may still be performed to further enhance various properties of the film. In some embodiments, the method may include optional operations before the method 300 is started, or the method may include additional operations after the low-κ mechanically stable material is deposited. In additional embodiments, such as Figure 3 As shown, method 300 may include flowing a deposition precursor into a substrate processing region of a semiconductor processing chamber at operation 305. In an embodiment, a substrate may be present in a substrate processing region of a semiconductor processing chamber while the deposition precursor is flowing into the chamber.

[0033] The deposition precursor may include a carbon chain. By providing one or more deposition precursors having a carbon chain, closed nanopores may be formed in the film, thereby reducing the dielectric constant of the film and improving the mechanical properties of the film. In an embodiment, the deposition precursor may include a silicon-containing precursor. The silicon-containing precursor may include a carbon chain (e.g., CH2-CH2). In additional embodiments, the silicon-containing precursor may be characterized by Formula 1: Each R may be independently selected from an alkyl group (eg, a C1-C6 alkyl group), an alkoxy group, an olefin group, an alkyne group, an acrylate, a halide, NO2, NH2, CN, NCO, NCS or C=OR. In Formula 1, n may be between 1 and 12.

[0034] In further embodiments, the silicon-containing precursor may include a precursor having Si-O bonds and / or Si-C bonds, and may include a linear branched silicon-containing precursor, a cyclic silicon-containing precursor, or any number of additional silicon-containing precursors. For example, the silicon-containing precursor may be characterized by Formula 2: Each R can be independently selected from an alkyl group (eg, a C1-C6 alkyl group), an alkoxy group, an alkene group, an alkyne group, an acrylate, a halide, NO2, NH2, CN, NCO, NCS or C=OR.

[0035] In some embodiments, the deposition precursor may further include molecular oxygen (O2). In embodiments, the flow rate of O2 relative to the flow rate of the silicon-containing precursor may be maintained at a flow rate ratio that facilitates the formation of a deposited low-κ film having a low dielectric constant (κ value) and high mechanical stability, which may be reflected by film properties such as Young's modulus and hardness, etc. Additionally or alternatively, the deposition precursor may also include hydrogen, such as diatomic hydrogen (H2).

[0036] In further embodiments, the deposition precursor may include a carbon-containing precursor. In embodiments, the carbon-containing precursor may include a carbon chain. For example, the carbon-containing precursor may be a hydrocarbon chain or may be a carbon chain including other elements (such as oxygen). It is contemplated that the carbon-containing precursor may provide a carbon chain, and the silicon-containing precursor may or may not include a carbon chain. Therefore, when a carbon-containing precursor having a carbon chain is provided, the silicon-containing precursor may be a conventional silicon compound for depositing silicon-containing materials. In such embodiments, the carbon-containing precursor may include, for example, an alkyl group, an alkoxy group, an olefin group, an alkyne group, an acrylate, or any other carbon-containing precursor having a carbon chain. For example, the carbon-containing precursor may include those having Formula 3: Wherein R can be an alkyl group (e.g., a C1-C6 alkyl group), an alkoxy group, an olefin group, an alkyne group, an acrylate, a halide, NO2, NH2, CN, NCO, NCS or C=OR. In Formula 1, n can be between 1 and 12. A and B can be independently selected from C or Si.

[0037] In further embodiments, the deposition precursors may also include one or more carrier gases, such as helium (He), nitrogen (N2), and argon (Ar). Although one or more carrier gases may be delivered with the other deposition precursors, the carrier gases may be considered inert gases that do not react to form part of the deposited low-κ film.

[0038] In an embodiment, the flow rate of the silicon-containing precursor can be greater than or about 100 milligrams per minute (mgm), greater than or about 110 mgm, greater than or about 120 mgm, greater than or about 130 mgm, greater than or about 140 mgm, greater than or about 150 mgm, greater than or about 160 mgm, greater than or about 170 mgm, greater than or about 180 mgm, greater than or about 190 mgm, greater than or about 200 mgm, greater than or about 210 mgm, greater than or about 220 mgm, greater than or about 230 mgm, greater than or about 240 mgm, greater than or about 250 mgm, or greater. The flow rate of one or more carrier gases may be greater than or about 300 sccm, greater than or about 320 sccm, greater than or about 340 sccm, greater than or about 360 sccm, greater than or about 380 sccm, greater than or about 400 sccm, greater than or about 420 sccm, greater than or about 440 sccm, greater than or about 460 sccm, greater than or about 480 sccm, greater than or about 500 sccm, or greater.

[0039] In some embodiments, it has been observed that an excess flow rate of O2 relative to the silicon-containing precursor can increase the dielectric constant of the deposited low-κ film to an abnormally large extent. It is believed that the excess O2 flow rate in these cases may result in an increased number of reactions between oxygen and hydrogen in the film, thereby producing hydroxyl (—OH) groups. In many embodiments, the dielectric constant of the silicon-oxygen-and-carbon-containing low-κ film may be highly sensitive to the number of hydroxyl groups in the film. A relatively small increase in the amount of hydroxyl groups in the film (e.g., an increase of less than or about 1 atomic percent) may cause a relatively large increase in the dielectric constant of the film (e.g., an increase of greater than or about 10%). In some embodiments, the O2 flow rate can be less than or about 200 sccm, less than or about 180 sccm, less than or about 160 sccm, less than or about 150 sccm, or less.

[0040] In additional embodiments, deposition precursors flowing into a substrate processing region of a semiconductor process chamber can change the pressure in the chamber. In embodiments, during formation of a low-κ film, the semiconductor substrate chamber pressure can be characterized by a pressure greater than or about 1 Torr, greater than or about 2 Torr, greater than or about 3 Torr, greater than or about 4 Torr, greater than or about 5 Torr, greater than or about 6 Torr, greater than or about 7 Torr, greater than or about 8 Torr, greater than or about 9 Torr, greater than or about 10 Torr, or more. Similarly, the pressure can be characterized by a pressure less than or about 10 Torr, less than or about 9 Torr, less than or about 8 Torr, less than or about 7 Torr, less than or about 6 Torr, less than or about 5 Torr, or less.

[0041] Embodiments of method 300 may include generating a deposition plasma from a deposition precursor at operation 310. In embodiments, the deposition plasma may be generated from the deposition precursor within a processing region, such as by providing RF power to a faceplate to generate a plasma within a substrate processing region of a semiconductor process chamber. Alternatively, the deposition plasma may be formed away from the substrate processing region, such as in a remote plasma system. By forming a remote plasma, a Si—O—Si network may be maintained in the deposited film. The deposition plasma may be generated at any of the frequencies described above, and may be generated at a frequency less than 15 MHz (e.g., 13.56 MHz). Although higher frequencies may be used, in some embodiments, generation of a lower frequency plasma may help remove carbon during processing, as opposed to operating at a higher plasma frequency. Further, the plasma can be formed using an RF power of less than or about 1000 W, and the plasma can be formed at a power of less than or about 900 W, less than or about 800 W, less than or about 700 W, less than or about 600 W, less than or about 500 W, less than or about 400 W, less than or about 300 W, less than or about 250 W, less than or about 200 W, less than or about 150 W, less than or about 100 W, or less.

[0042] Embodiments of method 300 may include, at operation 315, depositing a low-κ film on a substrate. In embodiments, the substrate is present in a substrate processing region of a semiconductor process chamber, and the low-κ film is formed from deposition plasma effluents generated from a deposition plasma also present in the processing region. In some embodiments, the substrate may be characterized by a temperature during deposition of less than or about 420°C, less than or about 410°C, less than or about 410°C, less than or about 5 ... In an embodiment, the deposited low-κ film may be characterized by an increased Young's modulus and an increased hardness at a higher temperature. On the other hand, too high a temperature may cause the carbon in the deposited low-κ film to volatilize and degas from the film. At too high a temperature, a significant amount of carbon may be removed from the low-κ film as carbon oxides (e.g., CO, CO2) and volatile organic compounds (e.g., -CH3, CH4), thereby reducing the carbon level in the film. The reduced carbon level may increase the dielectric constant (κ value) of the film to a level greater than 3.0, greater than or about 3.1, greater than or about 3.2, greater than or about 3.3, greater than or about 3.4, greater than or about 3.5 or greater. In some embodiments, the substrate may be characterized by a temperature of less than or about 450°C during the deposition of the low-κ film.

[0043] In some embodiments, the deposition rate of low-κ films may exceed and can be deposited at a rate greater than or about Greater than or approximately Greater than or approximately Greater than or approximately Greater than or approximately Greater than or approximately Greater than or approximately Greater than or approximately Greater than or approximately Greater than or approximately or greater. After being deposited to a sufficient thickness (e.g., less than or about ), many conventional processes may then transfer the substrate to a second chamber to perform processing, such as UV treatment or other post-deposition processing. This may reduce processing throughput and may increase production costs due to the need for additional chambers or tools to perform processing. However, the present technology can produce materials including silicon- and carbon-containing materials (e.g., carbon-doped silicon oxide) that can be characterized by sufficient material properties as deposited without the need for additional processing (such as UV treatment). Although embodiments of the present technology may include additional processing after deposition, the properties of the deposited films may include a range of improvements over conventional techniques.

[0044] As described above, the processing methods of the present technology may include embodiments of deposition precursors and processing conditions that form low-κ films with low dielectric constants and high mechanical stability. In an embodiment of the processing method 300, the deposited low-κ film may be formed as a silicon-carbon- and oxygen-containing film having a dielectric constant of less than or about 3.0, less than or about 2.9, less than or about 2.8, less than or about 2.7, less than or about 2.6, less than or about 2.5, less than or about 2.4, less than or about 2.3, less than or about 2.2, less than or about 2.1, less than or about 2.0 or less. The low dielectric constant of the film may be at least partially attributed to the porosity of the film. In an embodiment, the use of a precursor comprising a carbon chain enables the formation of closed nanopores in the film. The formation of closed nanopores reduces the dielectric constant of the film while maintaining mechanical stability. In conventional film formation, achieving the previously stated dielectric constants may only be possible with highly porous atomic-scale networks, typically requiring poragens and / or spin-coating application methods.

[0045] In some embodiments, the reduced dielectric constant (κ value) and the improved mechanical stability of the low-κ film may be associated with an increased level of methyl groups as part of the overall carbon in the film. The retention of methyl groups in the low-κ film can maintain a higher carbon atomic percentage in the material, which in turn can reduce the dielectric constant of the material. However, compared to other hydrocarbon groups, methyl groups are considered to have less destabilizing effects on the mechanical properties of the low-κ film. In an embodiment, the increased methyl group level may be partially attributed to a deposition precursor comprising at least one carbon chain. At the deposition temperature, the carbon chain can be easily hydrogenated to form methyl groups. The deposited low-κ film can be characterized by the atomic (i.e., molecular) percentage of methyl groups (-CH3) in the low-κ film relative to silicon oxide (SiO) groups, which is measured by the area of ​​the infrared absorption peak attributed to these groups. In embodiments, the atomic percentage of methyl groups (-CH3) can be greater than 2.5 atomic percentage, greater than 2.75 atomic percentage, greater than or about 3 atomic percentage, greater than 3.25 atomic percentage, greater than 3.5 atomic percentage, greater than 3.75 atomic percentage, greater than 4 atomic percentage, or greater. Similarly, the atomic percentage of methyl groups can be less than or about 10.0 atomic percentage, less than or about 9.5 atomic percentage, less than or about 9.0 atomic percentage, less than or about 8.5 atomic percentage, less than or about 8.0 atomic percentage, less than or about 7.5 atomic percentage, less than or about 7.0 atomic percentage, or less.

[0046] The processing methods of the present technology include embodiments that produce deposited low-κ films characterized by high mechanical stability. In embodiments, the deposited low-κ films may be characterized by a Young's modulus of greater than or about 3.0 GPa, and may be characterized by a Young's modulus of greater than or about 3.5 GPa, greater than or about 4.0 GPa, greater than or about 4.5 GPa, greater than or about 5.0 GPa, greater than or about 5.5 GPa, greater than or about 6.0 GPa, greater than or about 6.5 GPa, greater than or about 7.0 GPa, greater than or about 7.5 GPa, greater than or about 8.0 GPa, greater than or about 8.5 GPa, or more. In further embodiments, the deposited low-κ films may be characterized by a hardness of greater than or about 0.2 GPa, and may be characterized by a hardness of greater than or about 0.3 GPa, greater than or about 0.4 GPa, greater than or about 0.5 GPa, greater than or about 0.6 GPa, greater than or about 0.7 GPa, or more. These and other embodiments of the present technology provide a route to forming deposited low-κ films from silicon-containing plasma effluents, which can be produced by conventional plasma deposition methods with low dielectric constant, high Young's modulus and high hardness without the need for additional processing operations, such as UV curing.

[0047] In the foregoing description, for the purpose of explanation, numerous details have been 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 certain embodiments may be practiced without some of these details or with additional details.

[0048] Several embodiments have been disclosed, and 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. In addition, in order to avoid unnecessary confusion of the present technology, many well-known processes and elements are not described. Therefore, the foregoing description should not be considered to limit the scope of the present technology.

[0049] In the case of providing a range of values, unless otherwise expressly specified herein, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed, with an accuracy of the smallest quantile to the unit of the lower limit. Any narrower range between any recorded value or unrecorded intermediate value in the recorded range and any other recorded value or intermediate value in the recorded range will be included. The upper and lower limits of those smaller ranges may be independently included in the range or excluded from the range, and each range in which any one is included, any one is not included, or both are included in the smaller range is also included in the present technology, subject to any specifically excluded limits in the recorded range. In the case where the recorded range includes one or both of the limits, the range excluding one or both of those included limits is also included.

[0050] As used herein and in the appended claims, the singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise. Thus, for example, reference to "a material" includes a plurality of such materials and reference to "the precursor" includes reference to one or more precursors and equivalents thereof known to those skilled in the art, and so forth.

[0051] Furthermore, the words “comprise(s),” “comprising,” “contain(s),” “containing,” “include(s),” and “including,” when used in this specification and the following claims, are intended to specify the presence of stated features, integers, components, or operations, but the words do not exclude the presence or addition of one or more other features, integers, components, operations, actions, or groups.

Claims

1. A semiconductor processing method, comprising: flowing one or more deposition precursors into a semiconductor processing system, wherein the one or more deposition precursors include a silicon-containing precursor, wherein the silicon-containing precursor includes a carbon chain; generating a deposition plasma from the one or more deposition precursors; and Plasma effluents from the deposition plasma deposit a silicon and carbon containing material on a substrate, wherein the deposited silicon and carbon containing material is characterized by a dielectric constant of less than or about 3.

0.

2. The semiconductor processing method of claim 1, wherein the silicon-containing precursor is characterized by Formula 1: wherein R is hydrogen, alkyl, alkoxy, alkene, alkyne, acrylate, halide, NO2, NH2, CN, NCO, NCS or C=OR, and wherein n is between 1 and 12. 3 . The semiconductor processing method of claim 1 , wherein the silicon-containing precursor comprises a propane chain, a butane chain, a hexane chain or a heptane chain.

4. The semiconductor processing method of claim 1, wherein the deposition precursor further comprises: Molecular oxygen (O2), diatomic hydrogen (H2), or a combination of both.

5. The semiconductor processing method of claim 4, wherein generating the deposition plasma from the one or more deposition precursors comprises: The deposition plasma is formed in a remote plasma unit.

6. The semiconductor processing method of claim 1 wherein the silicon and carbon containing material is characterized by greater than or about 2.0 atomic percent incorporation of methyl groups.

7. The semiconductor processing method of claim 1, wherein the silicon and carbon containing material is characterized by a Young's modulus of greater than or about 3 GPa.

8. The semiconductor processing method of claim 1, wherein the silicon and carbon containing material is characterized by a hardness of greater than or about 0.5 GPa.

9. A semiconductor processing method comprising: flowing a deposition precursor to a semiconductor processing system, wherein the deposition precursor comprises a silicon-containing precursor and a carbon-containing precursor, and wherein the carbon-containing precursor is a chain compound; generating a deposition plasma from the one or more deposition precursors; as well as A silicon-and-carbon-containing material is deposited on a substrate from plasma effluents of the deposition plasma, wherein the deposited silicon-and-carbon-containing material is characterized by a dielectric constant of less than or about 3.

0.

10. The semiconductor processing method of claim 9, wherein a temperature is maintained at less than or about 420°C during generation of the deposition plasma.

11. The semiconductor processing method of claim 9, wherein the deposition precursor further comprises molecular oxygen (O2).

12. The semiconductor processing method of claim 9, wherein the deposition precursor further comprises diatomic hydrogen (H2).

13. The semiconductor processing method of claim 9, wherein generating the deposition plasma from the one or more deposition precursors comprises: The deposition plasma is formed in a remote plasma unit.

14. The semiconductor processing method of claim 9, wherein the deposited silicon and carbon containing material is characterized by a Young's modulus of greater than or about 5 GPa.

15. A semiconductor processing method comprising: flowing a deposition precursor into a substrate processing region of a semiconductor processing chamber, wherein the deposition precursor comprises a silicon-containing precursor, and wherein the deposition precursor comprises a carbon chain; generating a deposition plasma from the deposition precursor within the substrate processing region; and A silicon-and-carbon-containing material is deposited on the substrate from plasma effluents of the deposition plasma, wherein the deposited silicon-and-carbon-containing material is characterized by a dielectric constant of less than or about 3.0, and wherein the deposited silicon-and-carbon-containing material is characterized by a Young's modulus of greater than or about 4.0 GPa.

16. The semiconductor processing method of claim 15 wherein said silicon-containing precursor comprises said carbon chain of said deposition precursor.

17. The semiconductor processing method of claim 15, wherein the deposition precursor further comprises at least one carrier gas, the at least one carrier gas comprising helium or nitrogen (N2).

18. The semiconductor processing method of claim 15, wherein generating the deposition plasma comprises: An RF power of less than or about 500 W is applied.

19. The semiconductor processing method of claim 15, wherein the flow rate of the deposition precursor is characterized by less than or about 500 mg / min.

20. The semiconductor processing method of claim 15, further comprising: A post-deposition treatment is performed on the silicon-and-carbon-containing material, wherein the post-deposition treatment includes UV curing or thermal annealing.

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