Microwave plasma chemical vapor deposition of nanocrystal diamond films

Abstract

Embodiments include a modular high frequency emission source for the growth of low roughness nanocrystalline diamond films. In one embodiment, a method of manufacturing a nanocrystal diamond (NCD) film includes loading a nanodiamond seed silicon wafer or a bare silicon wafer that has been surface treated and incubated into a microwave plasma enhanced chemical vapor deposition (MWPECVD) chamber, and treating the nanodiamond seed silicon wafer or the bare silicon wafer that has been surface treated and incubated with a plasma of CxHy (y > = x), CO2, and H2 at a power greater than 50 W to form a nanocrystalline diamond layer thereon.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to U.S. Patent Application No. 18 / 228,555, filed July 31, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The embodiments relate to a method and apparatus for growing low-roughness nanocrystalline diamond films by microwave plasma chemical vapor deposition. Background Technology

[0004] High-frequency radiation systems are widely used in many different manufacturing technologies, including plasma processing, such as those in the semiconductor industry, display technology, and microelectromechanical systems (MEMS). Currently, the most common are radio frequency (RF) radiation systems with a single antenna. However, when generating plasma at higher frequencies (including microwave frequencies), plasmas with higher plasma densities and / or high concentrations of excited neutral species are formed. Unfortunately, high-frequency radiation systems generated by a single antenna, such as those used for plasma formation, have their own drawbacks.

[0005] Typical high-frequency radiation systems (such as systems that form microwave plasmas) use a single, large high-frequency or microwave radiation source (e.g., a magnetron) and a transmission path to guide microwave radiation from the magnetron to the processing chamber. For example, in typical high-power microwave applications in the semiconductor industry, the transmission path is a microwave waveguide. Waveguides are used because microwave power rapidly attenuates with distance outside of a waveguide designed to carry a microwave source of a specific frequency. Additional components such as tuners, couplers, mode converters, and the like are also required to transmit microwave radiation to the processing chamber. These components limit the construction of large systems (i.e., at least as large as the sum of the waveguide and associated components) and severely restrict the design. Thus, the geometry of the high-frequency radiation field that can be used to form the plasma is limited because the geometry of the high-frequency radiation field is similar to the shape of the waveguide.

[0006] Therefore, it is difficult to match the geometry of the high-frequency radiation field with the geometry of the substrate being processed. In particular, it is difficult to generate a high-frequency radiation field at microwave frequencies to form plasma or expose a substrate to radiation, where the process is performed uniformly over an entire area of ​​the substrate (e.g., a silicon wafer with a diameter of 200 mm, 300 mm, or larger, a glass substrate used in the display industry, or a continuous substrate or the like used in roll-to-roll manufacturing). Some microwave-generated plasmas can use slotted wire antennas to allow microwave energy to propagate across an extended surface. However, such systems are complex, require specific geometries, and have limitations on the power density that can be coupled to the plasma.

[0007] Furthermore, high-frequency radiation systems typically generate radiation fields and / or plasmas that are not highly uniform and / or cannot have spatially tunable densities. As the size of the substrates being processed continues to increase, addressing edge effects becomes increasingly difficult. Moreover, the inability to tunable radiation fields and / or plasmas limits the ability to modify processing formulations to account for inhomogeneities in the incoming substrate and to adjust the radiation field density and / or plasma density of the processing system, where inhomogeneities are required to compensate for the system's design (e.g., to accommodate non-uniform radial velocities of rotating wafers within some processing chambers). Summary of the Invention

[0008] The embodiments include a method for manufacturing nanocrystalline diamond (NCD) films, the method comprising loading a nanocrystalline diamond seed silicon wafer into a microwave plasma-enhanced chemical vapor deposition (MWPECVD) chamber and using C x H y A plasma of (y≧x), CO2, and H2 is used to process a nanodiamond seed silicon wafer with a power greater than 50 W to form a nanocrystalline diamond layer thereon.

[0009] The embodiments include a method for manufacturing nanocrystalline diamond (NCD) films, the method comprising loading a surface-treated and incubated bare silicon wafer into a microwave plasma-enhanced chemical vapor deposition (MWPECVD) chamber, and using C x H y A plasma of (y≧x), CO2, and H2 is used to process a bare silicon wafer that has already undergone surface treatment and incubation at a power greater than 50 W to form a nanocrystalline diamond layer on it.

[0010] The embodiment includes a processing tool comprising a processing chamber and a modular high-frequency emission source. The processing chamber is configured to receive a nanodiamond seed silicon wafer or a bare silicon wafer that has undergone surface treatment and incubation. The modular high-frequency emission source is configured to provide C at a power greater than 50 W. x H y A plasma of (y≧x), CO2, and H2 is used to form a nanocrystalline diamond layer on a nanocrystalline silicon seed wafer or a bare silicon wafer that has undergone surface treatment and incubation. In one embodiment, each high-frequency emission module includes an oscillator module, an amplification module, and an applicator. In one embodiment, the oscillator module includes a voltage control circuit and a voltage-controlled oscillator. In one embodiment, the amplification module is coupled to the oscillator module. In one embodiment, the applicator is coupled to the amplification module. In one embodiment, the applicator is positioned opposite a chuck in a processing chamber on which one or more substrates are processed.

[0011] The above overview does not include an exhaustive list of all embodiments. It is envisioned that all systems and methods are included, which can be implemented according to all suitable combinations of the various embodiments summarized above, and those disclosed in the embodiments below and specifically pointed out in the claims filed with this application. Such combinations have specific advantages not specifically listed in the above overview. Attached Figure Description

[0012] Figure 1A This is a schematic diagram of a processing tool including a modular high-frequency emission source according to one embodiment.

[0013] Figures 1B to 1D According to one embodiment of this disclosure, it is achieved through a linear antenna-based ( Figure 1B ) and two different resonator-based ( Figure 1C and Figure 1D Comparative images of nanocrystalline diamond (NCD) films deposited in a MWPECVD chamber.

[0014] Figure 2A This is a schematic block diagram of a solid-state high-frequency emission module for growing low-roughness nanocrystalline diamond films according to one embodiment.

[0015] Figure 2B This is a schematic block diagram of an electronic device with a modular high-frequency emission source according to one embodiment, the modular high-frequency emission source including multiple oscillator modules for the growth of low-roughness nanocrystalline diamond films and feedback control.

[0016] Figure 2CThis is a schematic block diagram of an electronic device with a modular high-frequency emission source according to one embodiment, the modular high-frequency emission source including multiple oscillator modules for the growth of low-roughness nanocrystalline diamond films.

[0017] Figure 2D This is a schematic block diagram of an electronic device having a modular high-frequency emission source according to one embodiment, the modular high-frequency emission source including a high-frequency emission module with a shared oscillator module for the growth of low-roughness nanocrystalline diamond films.

[0018] Figure 3 This is a cross-sectional view of an applicator according to one embodiment, which can be used to couple microwave radiation into a processing chamber for the growth of low-roughness nanocrystalline diamond films.

[0019] Figure 4 This is a cross-sectional view of an applicator array positioned on a dielectric sheet, which is part of a processing chamber, according to one embodiment.

[0020] Figure 5A This is a plan view of an applicator array according to one embodiment, which can be used to couple high-frequency radiation into a processing chamber for the growth of low-roughness nanocrystalline diamond films.

[0021] Figure 5B This is a plan view of an applicator array according to an additional embodiment, which can be used to couple high-frequency radiation into a processing chamber for the growth of low-roughness nanocrystalline diamond films.

[0022] Figure 5C This is a plan view of an applicator array and multiple sensors according to one embodiment for detecting radiation field and / or plasma conditions for the growth of low-roughness nanocrystalline diamond films.

[0023] Figure 5D This is a plan view of an applicator array formed in two zones of a multi-zone processing tool according to one embodiment for the growth of a low-roughness nanocrystalline diamond film.

[0024] Figure 6 A block diagram of an exemplary computer system, according to one embodiment, is shown that can be used in conjunction with a modular microwave radiation source for the growth of low-roughness nanocrystalline diamond films. Detailed Implementation

[0025] The methods described in the embodiments herein include a method for growing low-roughness nanocrystalline diamond films by microwave plasma chemical vapor deposition. In one particular embodiment, a microwave plasma source including a microwave dielectric resonance antenna (DRA) array is used as the plasma source for growing low-roughness nanocrystalline diamond films on a silicon substrate.

[0026] The apparatus according to the embodiments described herein includes a modular high-frequency transmitter source comprising an array of high-frequency transmitter modules, wherein each module includes an oscillator module, an amplification module, and an applicator. Numerous specific details are set forth in the following description to provide a thorough understanding of the embodiments. It will be apparent to those skilled in the art that the embodiments may be practiced without these specific details. In other instances, well-known aspects have not been described in detail to avoid unnecessarily obscuring the embodiments. Furthermore, it should be understood that the various embodiments illustrated in the accompanying drawings are illustrative representations and are not necessarily drawn to scale.

[0027] Examples include a modular high-frequency emission source comprising an array of high-frequency emission modules for the growth of low-roughness nanocrystalline diamond films. As used herein, "high-frequency" electromagnetic radiation includes radio frequency radiation, extremely high frequency radiation, ultra-high frequency radiation, and microwave radiation. "High frequency" may refer to frequencies between 0.1 MHz and 300 GHz. According to one embodiment, each high-frequency emission module includes an oscillator module, an amplification module, and an applicator. In one embodiment, the oscillator module and the amplification module comprise electrical components that are entirely solid-state electronic components.

[0028] To provide context, current-technical nanocrystalline diamond films exhibit surface roughness ranging from 10 to 60 nm root mean square (rms) (measured by AFM) using microwave plasmas containing CH4, H2, and CO2 gases. The surface roughness can be reduced to approximately 3.5 nm by using DC bias on the substrate and adding argon to the gas mixture. Pulsed plasmas have also been reported to reduce surface roughness. However, a drawback of these methods is that they typically result in slower growth rates.

[0029] According to one or more embodiments of this disclosure, a method for generating microwave plasma using a dielectric resonant antenna is described, differing from current-technical microwave plasma sources using resonant cavity or slotted antenna methods. In one embodiment, a surface roughness of less than 3.5 nm, for example, about 3.2 nm, is achieved using a continuous-wave (i.e., non-pulsed) microwave source with CH4, H2, and CO2 gases. Advantages of implementing the embodiments described herein may include growth rates that are not compromised by the use of other techniques, such as biasing, pulsed, or the addition of argon. According to one or more embodiments of this disclosure, a separately controlled DRA array allows for the generation of large-area microwave plasma, resulting in uniform large-area film deposition.

[0030] In a particular embodiment, resonator-based microwave plasma-enhanced chemical vapor deposition is used to perform the growth of low-roughness nanocrystalline diamond films.

[0031] To provide context, nanocrystalline diamond (NCD) films synthesized via plasma-enhanced chemical vapor deposition (PECVD) have attracted considerable attention due to their unique properties, including high hardness, low coefficient of friction, and high transparency under visible light. Despite the numerous advantages of NCD films, a key research area for depositing NCD films lies in reducing their surface roughness to further expand their application range.

[0032] Typically, PECVD of NCD involves the use of hydrogen and hydrocarbon gases (and carbon dioxide). Depending on the processing conditions, the roughness of the NCD film can range from 10 to 60 nm. By applying a negative bias and tuning the processing parameters, NCD films with a root mean square roughness ≤12 nm have been demonstrated.

[0033] By introducing inert gases (such as argon and / or nitrogen) into the process gas mixture, NCD films with roughness less than 15 nm can be deposited using a linear antenna microwave (MW) PECVD system. Coupling of a negative bias with an argon-rich (98%) CH4 / H2 / Ar plasma yielded an ultra-high roughness NCD film of 9.6 nm. Using a plasma pulse, NCD films with roughness as low as 3.5 nm can be obtained via a linear antenna. However, the deposition rate is significantly reduced when using inert gases or plasma pulses.

[0034] According to one or more embodiments of this disclosure, a method for depositing a low-roughness NCD film is described. This method involves using a resonator-based MWPECVD chamber and a simple process gas, without involving bias, pulse, and / or inert gases.

[0035] In one embodiment, a nanodiamond seed silicon wafer and / or a bare silicon wafer that has undergone surface treatment and incubation are first placed into a resonator-based MWPECVD chamber. Depending on the processing requirements, 1 to 50 resonators can be used, with exemplary arrangements as described below.

[0036] Next, use C x H y The sample was processed with plasmas of (y≧x), CO2, and H2 at a power greater than 50 W. As used in this paper, C x H y This can refer to hydrocarbon gases, liquids, and / or solid carbonaceous precursors. In one embodiment, no additional process gas is required to assist in smoothing the surface of the NCD membrane. In one embodiment, the stage temperature is maintained between 20 and 600°C throughout the process, and the gap between the stage and the plasma source is greater than 10 mm. The processing duration can be adjusted according to the desired membrane thickness.

[0037] Figures 1B to 1D According to one embodiment of this disclosure, it is achieved by using a linear antenna ( Figure 1B ) and two different resonator-based ( Figure 1C and Figure 1D Comparative images of nanocrystalline diamond (NCD) films deposited in a MWPECVD chamber. The samples were characterized by scanning electron microscopy and atomic force microscopy. It was observed that using only C... x H y In the CO2 / H2 gas configuration, a significantly smoother NCD film with a roughness of less than 10 nm was obtained using a MWPECVD chamber based on two resonators, compared to a roughness of 27 nm for films obtained using MWPECVD based on a linear antenna. Other film properties, such as Raman measurements (325 nm laser), hardness, and modulus, have also been verified to be equivalent to those obtained using a MWPECVD chamber based on a linear antenna. Figures 1B to 1D Images 180, 185, and 190 respectively demonstrate the effectiveness and success of using a resonator-based MWPECVD chamber in a method for growing low-roughness NCD films using a simplified process gas without compromising the deposition rate.

[0038] In one embodiment, in the case of a wafer that has already undergone surface treatment and incubation, forming the treated substrate surface includes one or more cycles of exposure to a first mild plasma. In one or more embodiments, the first plasma source is located at a first distance D1 from the top surface of the substrate. In some embodiments, the first distance D1 is greater than or equal to 10 mm, 15 mm, 20 mm, or 25 mm. The treated substrate is incubated together with a carbon-rich gas flow and a second plasma to nucleate diamond particles, thereby forming a diamond core layer on the top surface of the substrate. In one or more embodiments, the diamond core layer is formed in a second plasma processing chamber using a second mild plasma generated by a plasma source. In other embodiments, the diamond core layer is formed in a first plasma processing chamber using a second mild plasma generated by a plasma source. In some embodiments, the second mild plasma may be generated by the first plasma source, but using a different gas (composition).

[0039] As used herein, “substrate surface” can refer to any substrate surface on which a layer may be formed. A substrate surface may have one or more features formed thereon, one or more layers formed thereon, and combinations thereof. Before depositing the molybdenum-containing layer, the substrate (or substrate surface) may be pretreated, for example by polishing, etching, reduction, oxidation, halogenation, hydroxylation, annealing, baking, or the like.

[0040] The substrate can be any substrate on which materials can be deposited, such as a silicon substrate, a III-V compound substrate, a silicon-germanium (SiGe) substrate, an epitaxial substrate, a silicon-on-insulator (SOI) substrate, a display substrate (such as a liquid crystal display (LCD), a plasma display, an electroluminescence (EL) lamp display), a solar cell array, a solar panel, a light-emitting diode (LED) substrate, a semiconductor wafer, or the like. In some embodiments, one or more additional layers may be disposed on the substrate such that a polymerizable seed layer can be formed at least partially thereon. For example, in some embodiments, a layer comprising a metal, nitride, oxide, or the like, or a combination thereof, may be disposed on the substrate, and may have a polymerizable seed layer formed on such one or more layers. In one or more embodiments, the substrate comprises silicon (Si) or polycrystalline silicon (p-Si). In some embodiments, the substrate comprises a polycrystalline silicon substrate. In some embodiments, the substrate is not chemically and / or physically modified.

[0041] On the other hand, using solid-state electronics instead of magnetrons can significantly reduce the size and complexity of high-frequency radiation sources. In particular, solid-state components are much smaller than the aforementioned magnetron hardware. Furthermore, the use of solid-state components allows for the elimination of the bulky waveguides required to transmit high-frequency radiation to the processing chamber. Instead, high-frequency radiation can be transmitted using coaxial cable wiring. The elimination of waveguides also allows for the construction of large-area modular high-frequency emission sources, where the size of the plasma formed is not limited by the waveguide size. Instead, arrays of high-frequency emission modules can be constructed according to a given pattern that allows for the formation of plasmas of arbitrary size (and shape) to match the shape of any substrate. Moreover, the cross-sectional shape of the applicators can be selected so that the applicator array can be arranged as closely as possible (i.e., a tightly packed array).

[0042] The use of high-frequency transmitter module arrays also provides greater flexibility in terms of the ability to locally alter the radiation field and / or plasma density by independently changing the power settings of the amplification modules of each high-frequency transmitter module. This allows for uniform optimization during radiation field exposure and / or plasma processing, such as adjustments for wafer edge effects, adjustments for incoming wafer inhomogeneities, and the ability to adjust radiation field exposure and / or plasma density for processing systems where inhomogeneities are required to compensate for the design of the processing system (e.g., to accommodate non-uniform radial velocities of rotating wafers in some processing chambers).

[0043] Additional embodiments may also include one or more radiation field and / or plasma monitoring sensors. This embodiment provides a method for locally measuring plasma density, or electric field strength, or any other plasma or radiation field property by each applicator, and using this measurement as part of a feedback loop to control the power applied to each high-frequency transmitting module. Therefore, each high-frequency transmitting module may have independent feedback, or a subset of the high-frequency transmitting modules in the array may be grouped into multiple control regions, where the feedback loop controls a subset of the high-frequency transmitting modules within the control region.

[0044] In addition to enhancing the tunability of the radiation field and / or plasma, the use of a single high-frequency emitter module provides a greater power density than currently available in existing radiation and / or plasma sources. For example, a high-frequency emitter module can allow power densities approximately five times or more greater than those of typical RF plasma processing systems. For instance, a typical power input to a plasma-enhanced chemical vapor deposition process is approximately 3000 W, providing approximately 4 W / cm² for a 300 mm diameter wafer. 2 The power density is [not specified]. In contrast, the high-frequency transmission module according to the embodiment can use a 300 W power amplifier with an applicator having a diameter of 4 cm to provide approximately 24 W / cm² at an applicator arrangement density of approximately 1. 2The power density is 27 W / cm², achieved with an applicator arrangement density of 1 / 3 and using a 1000 W power amplifier. 2 The power density is 80 W / cm², achieved with an applicator arrangement density of 1 and using a 1000 W power amplifier. 2 The power density.

[0045] Common methods for fabricating high-frequency radiation sources and / or plasmas (e.g., microwave plasmas) involve coupling high-frequency energy to a substrate, and / or, in the case of plasma formation, to a process gas, using a single oscillator module and a single electrode or applicator. However, using a multi-electrode / applicator structure with a single oscillator module, which is segmented to power each of the multiple electrodes / applicators, has drawbacks. Specifically, interference patterns inevitably form because the electromagnetic radiation generated by the single oscillator module results in electromagnetic radiation emitted by each applicator at the same frequency and with a fixed phase relative to each other. These interference patterns produce local maxima and minima, leading to non-uniform radiation fields and / or plasmas.

[0046] Therefore, embodiments include an array of high-frequency transmitting modules, each having its own oscillator module. When multiple oscillator modules are used, electromagnetic radiation generated by a first oscillator module will not interfere with electromagnetic radiation generated by a second oscillator module because the first and second oscillator modules cannot be at the same frequency, and there is no controlled phase difference between them. In embodiments where plasma is formed, the plasma will have improved uniformity due to the absence of interfering patterns. Similarly, when no plasma is formed (e.g., microwave heating or microwave curing), interfering patterns are avoided, and in one embodiment, more uniform substrate heating or curing is achieved. In another embodiment, a single oscillator module may be shared among two or more (but not all) high-frequency transmitting modules. In such embodiments, high-frequency transmitting modules sharing the same oscillator module may be referred to as phase-locked loop (PLL) high-frequency transmitting modules.

[0047] For reference Figure 1AA cross-sectional view of a processing tool 100 according to one embodiment is shown. In some embodiments, the processing tool 100 may be a processing tool suitable for any type of processing operation using a radiation field and / or plasma. For example, the processing tool 100 may be a processing tool for plasma-enhanced chemical vapor deposition (PECVD), plasma-enhanced atomic layer deposition (PEALD), etching and selective removal processes, and plasma cleaning. Although the embodiments described in detail herein are directed to plasma processing tools, it should be understood that additional embodiments may include the processing tool 100, which includes any tool utilizing high-frequency electromagnetic radiation. For example, a processing tool 100 utilizing high-frequency electromagnetic radiation without forming plasma may include an industrial heating, degassing, surface activation, and / or curing processing tool 100.

[0048] Generally, embodiments include a processing tool 100 that includes a chamber 178. In the processing tool 100, the chamber 178 may be a vacuum chamber. The vacuum chamber may include a pump (not shown) for removing gas from the chamber to provide a desired vacuum. Additional embodiments may include a chamber 178 including one or more gas lines 170 for supplying processing gas into the chamber 178 and an exhaust line 172 for removing byproducts from the chamber 178. In another embodiment, the chamber 178 may be a pressure vessel for maintaining a pressure equal to or greater than one atmosphere. Although not shown, it should be understood that the processing tool 100 may include a spray head for uniformly distributing processing gas on a substrate 174. In some embodiments, the processing tool 100 may optionally not include a chamber (i.e., the processing tool 100 may be a chamberless processing tool).

[0049] In one embodiment, substrate 174 may be supported on chuck 176. For example, chuck 176 may be any suitable chuck, such as an electrostatic chuck. The chuck may also include cooling lines and / or heaters to provide temperature control for substrate 174 during processing. Due to the modular configuration of the high-frequency emission module described herein, embodiments allow processing tool 100 to accommodate substrate 174 of any size. For example, substrate 174 may be a semiconductor wafer (e.g., 200 mm, 300 mm, 450 mm, or larger). Alternative embodiments also include substrate 174 other than semiconductor wafers. For example, embodiments may include processing tool 100 configured for processing glass substrates (e.g., for display technologies).

[0050] According to one embodiment, the processing tool 100 includes a modular high-frequency emission source 104. The modular high-frequency emission source 104 may include an array of high-frequency emission modules 105. In one embodiment, each high-frequency emission module 105 may include an oscillator module 106, an amplification module 130, and an applicator 142. In one embodiment, the oscillator module 106 and the amplification module 130 may include electrical components, which are solid-state electrical components. In one embodiment, each of the plurality of oscillator modules 106 may be communicatively coupled to a different amplification module 130. In some embodiments, the ratio between the oscillator modules 106 and the amplification modules 130 may be 1:1. For example, each oscillator module 106 may be electrically coupled to a single amplification module 130. In one embodiment, the plurality of oscillator modules 106 may generate electromagnetic radiation at more than one frequency and without a controlled phase relationship. Therefore, the electromagnetic radiation induced in the chamber 178 does not interact in a manner that produces inappropriate interference patterns.

[0051] In one embodiment, each oscillator module 106 generates electromagnetic radiation, which is transmitted to an amplification module 130. After being processed by the amplification module 130, the electromagnetic radiation is transmitted to an applicator 142. According to one embodiment, an array 140 of applicators 142 is coupled to a chamber 178, and each applicator emits electromagnetic radiation into the chamber 178. In some embodiments, the applicator 142 couples the electromagnetic radiation to a processing gas in the chamber 178 to generate plasma.

[0052] Now for reference Figure 2A This diagram illustrates a schematic block diagram of electronics in a high-frequency emission module 105 of a modular high-frequency emission source 104 according to one embodiment. In one embodiment, each oscillator module 106 includes a voltage control circuit 210 for providing an input voltage to a voltage-controlled oscillator 220 to generate high-frequency electromagnetic radiation at a desired frequency. Embodiments may include an input voltage between approximately 1V and 10V DC. The voltage-controlled oscillator 220 is an electronic oscillator whose oscillation frequency is controlled by the input voltage. According to one embodiment, the input voltage from the voltage control circuit 210 causes the voltage-controlled oscillator 220 to oscillate at a desired frequency. In one embodiment, the high-frequency electromagnetic radiation may have a frequency between approximately 0.1 MHz and 30 MHz. In one embodiment, the high-frequency electromagnetic radiation may have a frequency between approximately 30 MHz and 300 MHz. In one embodiment, the high-frequency electromagnetic radiation may have a frequency between approximately 300 MHz and 1 GHz. In one embodiment, the high-frequency electromagnetic radiation may have a frequency between approximately 1 GHz and 300 GHz. In one embodiment, one or more of the plurality of oscillator modules 106 may emit electromagnetic radiation of different frequencies.

[0053] According to one embodiment, electromagnetic radiation is transmitted from a voltage-controlled oscillator 120 to an amplification module 130. The amplification module 130 may include a driver / preamplifier 234 and a main power amplifier 236, both coupled to a power supply 239. According to one embodiment, the amplification module 130 may operate in continuous wave mode for the growth of low-roughness nanocrystalline diamond films.

[0054] In one embodiment, electromagnetic radiation, after being processed by amplification module 130, can be transmitted to applicator 142. However, due to output impedance mismatch, some power transmitted to applicator 142 may be reflected back. Therefore, some embodiments include detector module 281, which allows sensing the levels of forward power 283 and reflected power 282 and feeding them back to control circuit module 221. It should be understood that detector module 281 may be located in one or more different locations in the system. In one embodiment, control circuit module 221 interprets forward power 283 and reflected power 292 and determines the levels of control signal 285 communicatively coupled to oscillator module 106 and control signal 286 communicatively coupled to amplifier module 130. In one embodiment, control signal 285 adjusts oscillator module 106 to optimize high-frequency radiation coupled to amplification module 130. In one embodiment, control signal 286 adjusts amplifier module 130 to optimize output power coupled to applicator 142. In one embodiment, feedback control of oscillator module 106 and amplification module 130 may cause the level of reflected power to be less than about 5% of the forward power. In some embodiments, feedback control of oscillator module 106 and amplification module 130 may cause the level of reflected power to be less than about 2% of the forward power.

[0055] Therefore, the embodiment allows for an increase in the percentage of positive power coupled to the processing chamber 178 and an increase in the available power coupled to the plasma. Furthermore, impedance tuning using feedback control is superior to impedance tuning in a typical slit-plate antenna. In a slit-plate antenna, impedance tuning involves moving two dielectric metal blocks formed in the applicator. This involves the mechanical movement of two separate components in the applicator, which increases the complexity of the applicator. Moreover, mechanical movement may not be as precise as the frequency variation provided by the voltage-controlled oscillator 220.

[0056] Now for reference Figure 2BThis diagram illustrates a portion of a solid-state electronic device comprising an array of modular high-frequency emission sources 104 according to one embodiment. In the illustrated embodiment, each high-frequency emission module 105 includes an oscillator module 106 communicatively coupled to a different amplification module 130. Each amplification module 130 may be coupled to a different applicator 142. In one embodiment, control circuitry 221 may be communicatively coupled to both the oscillator module 106 and the amplification module 130.

[0057] In the illustrated embodiment, both the oscillator module 106 and the amplification module 130 are formed on a single board 290, such as a printed circuit board (PCB). However, it should be understood that the oscillator module 106 and the amplification module 130 may be formed on two or more different boards 290. In the target embodiment, four high-frequency emission modules 105 are shown. However, it should be understood that the modular high-frequency emission source 104 may include two or more high-frequency emission modules 105. For example, the modular high-frequency emission source 104 may include two or more high-frequency emission modules, five or more high-frequency emission modules, ten or more high-frequency emission modules, or twenty-five or more high-frequency emission modules.

[0058] Now for reference Figure 2C This diagram illustrates a portion of a solid-state electronic device comprising a modular high-frequency transmitter 104 having an array of high-frequency transmitter modules 105 according to one embodiment. Except for the omission of control circuitry, Figure 2C Basically similar Figure 2B The system shown. In particular, in some embodiments, feedback control provided by the detector and control circuitry may not be required.

[0059] Now for reference Figure 2D This diagram illustrates a portion of a solid-state electronic device comprising a modular high-frequency transmitter 104 having an array of high-frequency transmitter modules 105 according to one embodiment, some of which are phase-locked. Figure 2D The diagram shows multiple oscillator modules 106, where each oscillator module 1061 and 1062 is shared by more than one high-frequency transmission module 105. For example, the high-frequency transmission module 105... A and 105 B The shared oscillator module 1061, and the high-frequency transmission module 105 C and 105 D A common oscillator module 1062 is used. Specifically, the oscillator module 1061 is communicatively coupled to the amplifier module 130. A and 130 B The oscillator module 1062 is communicatively coupled to the amplifier module 130.C and 130 D In this embodiment, the high-frequency transmitting module 105, which shares the same oscillator module 106, can be considered as a phase-locked loop. For example, the high-frequency transmitting module 105 A and 105 B They are phase-locked together because they share the oscillator module 1061 and the high-frequency transmission module 105. C and 105 D They are phase-locked because they share the oscillator module 1062. Although the high-frequency transmission module 105... A and 105 B They are phase-locked to each other, but it should be understood that the high-frequency transmission module 105 A and 105 B A high-frequency transmitting module 105 can be generated and coupled to the oscillator module 1062. C and 105 D The generated high-frequency radiation is of different frequencies. Furthermore, it is produced by the high-frequency transmitting module 105. A and 105 B The generated high-frequency radiation and the high-frequency transmitting module 105 C and 105 D The generated high-frequency radiation may not have any coordinated phase relationship.

[0060] Furthermore, despite Figure 2D Two phase-locked high-frequency transmitting modules 105 are shown, but any number of high-frequency transmitting modules 105 can be phase-locked by sharing the same oscillator module 106, as long as not all microwave amplifier circuitry blocks 130 in the modular high-frequency transmitter 104 are phase-locked. For example, the ratio of oscillator module 106 to high-frequency transmitting module can be 1:2, 1:3, 1:4, 1:5, etc. Furthermore, it should be understood that embodiments may include phase-locked high-frequency transmitting modules 105 that include feedback control, such as feedback control including a detector module and control circuitry, similar to the above description. Figure 2A As described.

[0061] For reference Figure 3The diagram shows a cross-sectional view of an applicator 142 according to one embodiment. In one embodiment, electromagnetic radiation is transmitted to the applicator 142 via a coaxial cable 351 coupled to a monopole 357 extending axially through the applicator 142. In embodiments where the electromagnetic radiation is microwave radiation, the monopole 357 may also extend into a channel 358 formed at the center of a dielectric resonant cavity 353. The dielectric resonant cavity 353 may be a dielectric material, such as quartz, alumina, titanium oxide, or the like. Additional embodiments may also include a resonant cavity 353 without material (i.e., the dielectric resonant cavity 353 may be air or a vacuum). According to one embodiment, the dielectric resonator is sized such that it supports resonance of the microwave radiation. Typically, the size of the dielectric resonant cavity 353 depends on the dielectric constant of the material used to form the dielectric resonant cavity 353 and the frequency of the microwave radiation. For example, a material with a higher dielectric constant will allow for the formation of a smaller resonant cavity 353. In embodiments where the dielectric resonant cavity 353 includes a circular cross-section, the diameter of the dielectric resonant cavity 353 may be between approximately 1 cm and 15 cm. In one embodiment, the cross-section of the dielectric resonant cavity 353 along the plane perpendicular to the monopole 357 may be of any shape, as long as the dimensions of the dielectric resonant cavity 353 support resonance. In the illustrated embodiment, the cross-section along the plane perpendicular to the monopole 357 is circular, but other shapes may also be used, such as polygons (e.g., triangles, rectangles, etc.), symmetrical polygons (e.g., squares, pentagons, hexagons, etc.), ellipses, or the like.

[0062] In one embodiment, the cross-section of the dielectric resonant cavity 353 may not be the same in all planes perpendicular to the monopole 357. For example, the cross-section of the bottom extension near the opening end of the applicator housing 355 may be wider than the cross-section of the dielectric resonant cavity near the channel 358. In addition to having cross-sections of different dimensions, the dielectric resonant cavity 353 may have cross-sections of different shapes. For example, the portion of the dielectric resonant cavity 353 near the channel 358 may have a circular cross-section, while the portion of the dielectric resonant cavity 353 near the opening end of the applicator housing 355 may be a symmetrical polygonal shape (e.g., pentagonal, hexagonal, etc.). However, it should be understood that embodiments may also include a dielectric resonant cavity 353 having a uniform cross-section in all planes perpendicular to the monopole 357.

[0063] According to one embodiment, the applicator 353 may also include an impedance-tuned post-circuit 356. The post-circuit 356 may be a movable housing that slides on the outer surface of the applicator housing 355. When impedance adjustment is required, an actuator (not shown) may slide the post-circuit 356 along the outer surface of the applicator housing 355 to change the distance D between the surface of the post-circuit 356 and the top surface of the dielectric resonant cavity 353. Thus, the embodiments provide more than one way to adjust the impedance in the system. According to one embodiment, the impedance-tuned post-circuit 356 may be used in conjunction with the feedback process described above to address impedance mismatch issues. Alternatively, the feedback process or the impedance-tuned post-circuit 356 may utilize itself to adjust impedance mismatch.

[0064] According to one embodiment, the applicator 142 functions as a dielectric antenna, directly coupling a microwave electromagnetic field to the processing chamber 178. A specific axial arrangement of the monopole 357 entering the dielectric resonant cavity 353 can generate TM01δ mode excitation. However, different excitation modes are possible for different applicator arrangements. For example, although in Figure 3 The diagram shows an axial arrangement, but it should be understood that the monopole 357 may enter the dielectric resonant cavity 353 using other orientations. In one such embodiment, the monopole 357 may enter the dielectric resonant cavity 353 laterally (i.e., through the sidewalls of the dielectric resonant cavity 353).

[0065] It should be understood that Figure 3 The applicator 142 shown is exemplary in nature, and embodiments are not limited to the design described. For example, Figure 3 The applicator 142 is particularly suitable for emitting microwave radiation. However, embodiments may include any applicator design configured to emit any high-frequency electromagnetic radiation for the growth of low-roughness nanocrystalline diamond films.

[0066] For reference Figure 4 The diagram illustrates a portion of a processing tool 100 according to one embodiment, having an array 140 of applicators 142 coupled to a chamber 178. In the illustrated embodiment, high-frequency electromagnetic radiation from the applicators 142 is coupled into the chamber 178 by positioning them near a dielectric plate 450. The proximity of the applicators 142 to the dielectric plate 450 allows high-frequency radiation to resonate within a dielectric resonant cavity 353. Figure 4A dielectric resonant cavity 353 (not shown) resonates to couple with a dielectric plate 450, which can then be coupled with a process gas in the chamber to generate plasma. In some embodiments that do not induce plasma, high-frequency radiation is coupled into the chamber volume to generate a radiation field. In one embodiment, the dielectric resonant cavity 353 may be in direct contact with the dielectric plate 450. In another embodiment, the dielectric resonant cavity 353 may be spaced apart from the surface of the dielectric plate 450, as long as microwave radiation can still be transmitted to the dielectric plate 450. In another embodiment, an applicator 142 may be disposed in a cavity in the dielectric plate 450. In yet another embodiment, the applicator 142 may pass through the dielectric plate 450, such that the dielectric resonant cavity 353 is exposed to the interior of the chamber 178.

[0067] In one embodiment, the applicator 142 may include any antenna design configured to emit high-frequency electromagnetic radiation of any frequency for the growth of a low-roughness nanocrystalline diamond film. In one embodiment, the array 140 of applicators may include more than one applicator 142 design. For example, the array 140 of applicators 142 may include a first applicator for emitting a first high-frequency radiation and a second applicator for emitting a second high-frequency radiation different from the first high-frequency radiation.

[0068] According to one embodiment, the array 140 of applicators 142 can be removed from the dielectric plate 450 (e.g., for maintenance, to rearrange the applicator array to accommodate a different sized substrate, or for any other reason) without removing the dielectric plate 350 from the chamber 178. Therefore, the applicators 142 can be removed from the processing tool 100 without releasing the vacuum in the chamber 178. According to another embodiment, the dielectric plate 450 can also be used as a gas injection plate or a spray head.

[0069] As described above, an array 140 of applicators can be arranged to cover a substrate 174 of any shape. Figure 5AThis is a plan view of an array 140 of applicators 142 arranged in a pattern that matches a circular substrate 174. By forming a plurality of applicators 142 in a pattern that substantially matches the shape of the substrate 174, the radiation field and / or plasma becomes tunable across the entire surface of the substrate 174. For example, each applicator 142 can be controlled to form a plasma with a uniform plasma density across the entire surface of the substrate 174, and / or to form a uniform radiation field across the entire surface of the substrate 174. Alternatively, one or more of the applicators 142 can be independently controlled to provide a variable plasma density across the surface of the substrate 174. In this way, incoming non-uniformities present on the substrate can be corrected. For example, applicators 142 near the outer periphery of the substrate 174 can be controlled to have different power densities than applicators near the center of the substrate 174. Furthermore, it should be understood that electromagnetic radiation of different frequencies without a controlled phase relationship is emitted using a high-frequency emission module 105 in order to eliminate the presence of standing waves and / or unwanted interference patterns.

[0070] exist Figure 5A In the array 140, the applicators 142 are arranged together in a series of concentric rings extending outward from the center of the substrate 174. However, the embodiments are not limited to this configuration, and any suitable spacing and / or pattern can be used depending on the needs of the processing tool 100. Furthermore, as mentioned above, the embodiments allow applicators 142 to have any symmetrical cross-section. Thus, the cross-sectional shape selected for the applicators can provide enhanced arrangement efficiency.

[0071] For reference Figure 5B A plan view of an array 140 of applicators 142 with non-circular cross-sections according to one embodiment is shown. The illustrated embodiment includes applicators 142 with hexagonal cross-sections. Using such applicators improves arrangement efficiency because the outer periphery of each applicator 142 can almost perfectly mate with adjacent applicators 142. Therefore, plasma uniformity can be further enhanced as the spacing between each applicator 142 can be minimized. Although... Figure 5B Adjacent applicators 142 with a common sidewall surface are shown, but it should be understood that embodiments may also include non-circular symmetrical shape applicators, which include a spacing between adjacent applicators 142.

[0072] For reference Figure 5C An additional plan view of the array 140 of the applicator 142 according to one embodiment is shown. In addition to also including a plurality of sensors 590, Figure 5C Array 140 in the reference is basically similar to the one mentioned above. Figure 5AThe array 140 is described. Multiple sensors provide improved process monitoring capabilities, which can be used to provide additional feedback control for each modular microwave source 105. In one embodiment, sensor 590 may include one or more different sensor types 590, such as plasma density sensors, plasma emission sensors, radiation field density sensors, radiation emission sensors, or the like. Positioning the sensors on the surface of substrate 174 allows monitoring of the radiation field and / or plasma properties at a given location in the processing chamber 100.

[0073] According to one embodiment, each applicator 142 may be paired with a different sensor 590. In this embodiment, the output from each sensor 490 can be used to provide feedback control for the corresponding applicator 142 paired with the sensor 590. Additional embodiments may include pairing each sensor 590 with multiple applicators 142. For example, each sensor 490 may provide feedback control for multiple applicators 142 with which it is located in close proximity. In yet another embodiment, feedback from multiple sensors 590 may be used as part of a multi-input multi-output (MIMO) control system. In one such embodiment, each applicator 142 may be adjusted based on feedback from multiple sensors 590. For example, a first sensor 490 directly adjacent to a first applicator 142 may be weighted to provide a control effect to the first applicator 142 that is greater than the control effect exerted on the first applicator 142 by a second sensor 490 located further away from the first applicator 142.

[0074] Now for reference Figure 5D An additional plan view is shown of an array 140 of applicators 142 positioned in a multi-zone processing tool 100 according to one embodiment. In one embodiment, the multi-zone processing tool 100 may include any number of zones. For example, the illustrated embodiment includes zones 5751 to 575. n Each region 575 can be configured to perform different processing operations on a substrate 174 that rotates through different regions 575. As shown, the first array 1402 is located in region 5752, while the second array 140... n Located in District 575 n However, depending on the needs of the apparatus, embodiments may include a multi-zone processing tool 100 having an array 140 with applicators 142 in one or more different zones 575. The spatially tunable density of the plasma and / or radiation field provided by the embodiments allows for adaptation to the non-uniform radial velocity of the rotating substrate 174 as it passes through the different zones 575.

[0075] In one embodiment, the ratio of oscillator module 106 to applicator 142 may be 1:1 (i.e., each applicator 142 is coupled to a different oscillator module 106). In other embodiments, the ratio of oscillator module 106 to applicator 142 may be 1:2, 1:3, 1:4, etc. For example, in an embodiment including two applicator arrays 1402 and 140... n In each embodiment, each oscillator module 106 may be coupled to a first applicator 142 and a second array 140 in the first array 1402. n The second applicator 142 in the process.

[0076] Now for reference Figure 6 This diagram illustrates an exemplary computer system 660 for a processing tool 100 for growing low-roughness nanocrystalline diamond films according to one embodiment. In one embodiment, the computer system 660 is coupled to the processing tool 100 and controls the processing within the processing tool 100. The computer system 660 may be connected (e.g., networked) to other machines in a local area network (LAN), intranet, extranet, or the Internet. The computer system 660 may operate as a server or client machine in a client-server network environment, or as a peer machine in a peer-to-peer (or distributed) network environment. The computer system 660 may be a personal computer (PC), tablet PC, set-top box (STB), personal digital assistant (PDA), cellular phone, network device, server, network router, switch, or bridge, or any machine capable of executing a set of instructions (sequentially or otherwise) specifying the actions to be taken by that machine. Furthermore, although only a single machine is shown for computer system 660, the term "machine" should also be understood to include any collection of machines (e.g., computers) that individually or jointly execute a set (or more sets) of instructions to perform any one or more of the methods described herein.

[0077] Computer system 660 may include computer program product or software 622 having a non-transitory machine-readable medium storing instructions that can be used to program computer system 660 (or other electronic device) to perform a process according to an embodiment. Machine-readable medium includes any mechanism for storing or transmitting information in a machine-readable (e.g., computer-readable) form. For example, machine-readable (e.g., computer-readable) medium includes machine-readable (e.g., computer-readable) storage media (e.g., read-only memory (“ROM”), random access memory (“RAM”), disk storage media, optical storage media, flash memory devices, etc.), machine-readable (e.g., computer-readable) transmission media (electrical, optical, acoustic, or other forms of propagated signals (e.g., infrared signals, digital signals, etc.)), etc.

[0078] In one embodiment, the computer system 660 includes a system processor 602, a main memory 604 (e.g., read-only memory (ROM), flash memory, dynamic random access memory (DRAM), such as synchronous DRAM (SDRAM) or Rambus DRAM (RDRAM), etc.), a static memory 606 (e.g., flash memory, static random access memory (SRAM), etc.), and an auxiliary memory 618 (e.g., a data storage device), all of which communicate with each other via a bus 630.

[0079] System processor 602 represents one or more general-purpose processing devices, such as microsystem processors, central processing units, or the like. More specifically, the system processor may be a complex instruction set computing (CISC) microsystem processor, a reduced instruction set computing (RISC) microsystem processor, a very long instruction word (VLIW) microsystem processor, a system processor implementing other instruction sets, or a system processor implementing combinations of instruction sets. System processor 602 may also be one or more special-purpose processing devices, such as application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), digital signal system processors (DSPs), network system processors, or the like. System processor 602 is configured to execute processing logic 626 for performing the operations described herein.

[0080] The computer system 660 may further include a system network interface device 608 for communicating with other devices or machines. The computer system 660 may also include a video display unit 610 (e.g., a liquid crystal display (LCD), a light emitting diode display (LED), or a cathode ray tube (CRT)), an alphanumeric input device 612 (e.g., a keyboard), a cursor control device 614 (e.g., a mouse), and a signal generation device 616 (e.g., a speaker).

[0081] Auxiliary storage 618 may include machine-accessible storage medium 631 (or more specifically, computer-readable storage medium) having stored thereon one or more sets of instructions (e.g., software 622) embodying any one or more of the methods or functions described herein. During execution by computer system 660, software 622 may also reside wholly or at least partially within main memory 604 and / or system processor 602, which also constitute machine-readable storage media. Software 622 may further be transmitted or received on network 620 via system network interface device 608.

[0082] Although in the exemplary embodiment, machine-accessible storage medium 631 is shown as a single medium, the term "machine-readable storage medium" should be understood to include a single medium or multiple media (e.g., a centralized or distributed database, and / or associated caches and servers) that store one or more sets of instructions. The term "machine-readable storage medium" should also include any medium capable of storing or encoding a set of instructions executable by a machine and enabling the machine to perform any one or more of the methods. Therefore, the term "machine-readable storage medium" should include, but is not limited to, solid-state memory, and optical and magnetic media.

[0083] Specific exemplary embodiments have been described in the foregoing specification. It will be apparent that various modifications may be made thereto without departing from the scope of the appended claims. Therefore, the specification and drawings should be considered illustrative rather than restrictive.

Claims

1. A method of manufacturing a nanocrystalline diamond (NCD) film, the method comprising: loading a nanodiamond-seeded silicon wafer into a microwave plasma enhanced chemical vapor deposition (MWPECVD) chamber; and C x H y a plasma of CO2 and H2 at a power greater than 50 W to form a nanocrystalline diamond layer thereon.

2. The method of claim 1, wherein no other process gas is used to form the nanocrystalline diamond layer.

3. The method of claim 1, wherein a platen temperature of a platen in the MWPECVD chamber is maintained between 20 and 600 °C throughout the processing of the nanodiamond-seeded silicon wafer.

4. The method of claim 1, wherein a gap between the platen and a plasma source of the MWPECVD chamber is greater than 10 millimeters.

5. The method of claim 1, wherein the nanocrystalline diamond layer has a surface roughness of less than 10 nm rms.

6. The method of claim 1, wherein the nanocrystalline diamond layer has a surface roughness of less than 3.5 nm rms.

7. The method of claim 1, wherein the plasma is a continuous wave plasma.

8. A method of manufacturing a nanocrystalline diamond (NCD) film, the method comprising: loading a bare silicon wafer that has been surface treated and incubated into a microwave plasma enhanced chemical vapor deposition (CVD) chamber; and C x H y (y > x), CO2and H2plasma at a power greater than 50 W to form a nanocrystalline diamond layer thereon.

9. The method of claim 8, wherein no other process gas is used to form the nanocrystalline diamond layer.

10. The method of claim 8, wherein a platen temperature of a platen in the MWPECVD chamber is maintained between 20 and 600 °C throughout the processing of the bare silicon wafer that has been surface treated and incubated.

11. The method of claim 8, wherein a gap between the platen and a plasma source of the MWPECVD chamber is greater than 10 millimeters.

12. The method of claim 8, wherein the nanocrystalline diamond layer has a surface roughness of less than 10 nm rms.

13. The method of claim 8, wherein the nanocrystalline diamond layer has a surface roughness of less than 3.5 nm rms.

14. The method of claim 8, wherein the plasma is a continuous wave plasma.

15. A processing tool, comprising: a processing chamber configured to receive a nanodiamond-seeded silicon wafer or a bare silicon wafer that has been surface treated and incubated; and A modular high frequency emission source configured to provide C x H y a plasma of H2, CO2, and H2 to form a nanocrystalline diamond layer on the nanodiamond seed silicon wafer or the bare silicon wafer that has been surface treated and incubated, the modular high frequency emission source comprising: a plurality of high frequency launch modules, wherein each high frequency launch module comprises: an oscillator module, wherein each oscillator module comprises: a voltage control circuit; and a voltage controlled oscillator; an amplification module, wherein the amplification module is coupled to the oscillator module; and an applicator, wherein the applicator is coupled to the amplification module, and wherein the applicator is positioned opposite a chuck in the processing chamber on which one or more substrates are processed.

16. The processing tool of claim 15, wherein each high frequency launch module comprises a different oscillator module.

17. The process tool of claim 15, wherein two or more of the high frequency launch modules share an oscillator module.

18. The process tool of claim 15, wherein the high frequency is a microwave frequency.

19. The process tool of claim 15, wherein the high frequency electromagnetic radiation launched from the applicator excites a plasma.

20. The process tool of claim 15, wherein the high frequency is 0.1 MHz to 300 GHz.

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