Nanocrystalline diamond with amorphous interface layer

Abstract

A method for depositing nanocrystalline diamond films is described. This method may be used in the manufacture of integrated circuits. The method includes treating a substrate with plasma to form a treated substrate surface, incubating the treated substrate with a carbon-rich plasma to nucleate diamond particles on the treated substrate surface, and then treating the substrate with plasma to form a nanocrystalline diamond film. The resulting nanocrystalline diamond film is formed on an oxide-rich amorphous layer at the interface between the nanocrystalline diamond film and the silicon substrate.

Description

[Technical Field]

[0001]

[0001] Embodiments of the present disclosure relate to the field of electronic device manufacturing, and more specifically to integrated circuit (IC) manufacturing. More specifically, embodiments of the present disclosure provide a method for depositing a diamond-like carbon hard mask film on an amorphous interface layer. Film stacks containing diamond-like carbon directly above an amorphous layer directly above a substrate are also disclosed. [Background technology]

[0002]

[0002] As the semiconductor industry introduces a new generation of integrated circuits (ICs) with higher performance and better functionality, the density of elements forming such ICs is increasing, while the dimensions, size, and spacing of individual components or elements are decreasing. Until now, such reductions have been limited only by the ability to define structures using photolithography, but device shape dimensions with dimensions measured in micrometers or nanometers have created new limiting factors, such as the conductivity of metallic elements, the dielectric constant of insulating materials used between elements, or challenges in 3D NAND or DRAM processes. These limitations can be addressed by hard masks that are more durable and harder.

[0003]

[0003] Diamond is a material with high hardness, chemical inertness, high thermal conductivity, and good optical transparency, making it promising for microelectronics applications. Diamond has emerged as a promising candidate for countless microelectronics applications.

[0004]

[0004] However, there is a large discrepancy in the surface energies of diamond and silicon (6 J cm -2 Against 1.5 Jcm -2 ), a low adhesion coefficient for gaseous precursors (such as hydrocarbon radicals), and strong competition from the non-diamond phase result in a diamond nucleation density (approximately 10) on untreated silicon. 4 cm -2 ) is typically low.

[0005]

[0005] To address low diamond nucleation densities, substrates are typically pre-treated (e.g., mechanical abrasion or micro-chipping) and / or seeded with nanodiamond (ND) particles before deposition. However, such seeding methods consist of multiple solution-based procedures, are cumbersome, and are not suitable for cleanroom environments.

[0006]

[0006] Alternatively, bias-enhanced nucleation (BEN) is one of the few nucleation techniques that can be performed in situ. This involves impacting the surface of a negatively charged substrate with methane-rich (4-10%) ionized gas species, enabling the formation of a carbide layer with improved adhesion to the substrate. In BEN, 10 11 cm -2 Nucleation densities exceeding [a certain value] have been reported. Unfortunately, the application of BEN is limited by the presence of substrate surface damage (e.g., holes as deep as 2-3 μm in diameter), the difficulty of uniformly applying bias over a large area, and the need for a conductive substrate.

[0007]

[0007] In both seed processing technology and BEN, several researchers have reported the presence of a carbon-rich interface layer between the nanocrystalline diamond (NCD) film and the substrate. The working theory was that such a carbon-rich interface layer is extremely important for the subsequent formation of diamond nuclei. The role of SiC in diamond nucleation has not yet been elucidated, but such an interface layer mainly consists of silicon and carbon, with oxygen present at a minimum (<10 19 cm -3 The general view is that it is (or 0.1 atomic percent).

[0008]

[0008] Oxides, particularly silicon oxides, are far better understood and widely used than silicon carbide. Therefore, there is a need for a method to form nanocrystalline diamond (NCD) films on oxygen-containing materials. [Overview of the project]

[0009]

[0009] One or more embodiments of the present disclosure are directed to a method of forming a nanocrystalline diamond film. The method includes exposing a silicon substrate to a first plasma from a first plasma source. The first plasma source includes one or more of C x H y (where y ≥ x), carbon dioxide (CO2), hydrogen (H2), nitrogen (N2), and argon (Ar) for providing a processed substrate. The processed substrate is incubated with a gas stream containing a hydrocarbon and a second plasma to nucleate diamond particles and form a seed-treated substrate. The seed-treated substrate is exposed to a third plasma having a power exceeding 50 W to form a nanocrystalline diamond film. After the formation of the nanocrystalline diamond film, the nanocrystalline diamond film is formed directly on an amorphous oxide-rich layer formed directly on the silicon substrate.

[0010]

[0010] An additional embodiment of the present disclosure relates to a method of forming a diamond film. The method includes exposing a processed substrate to a gas stream containing a hydrocarbon to nucleate diamond particles on the upper surface of the substrate. The substrate includes an exposed amorphous oxide-rich layer. The diamond particles are exposed to a plasma having a power exceeding 50 W to form a nanocrystalline diamond film on the upper surface of a substrate that is not silicon.

[0011]

[0011] A further embodiment of the present disclosure is directed to an electronic device including a silicon substrate, an amorphous oxide layer directly above the silicon substrate, and a nanocrystalline diamond film directly above the amorphous oxide layer.

[0012]

[0012] To enable a more detailed understanding of the above-described features of the Disclosure, a more detailed description of the Disclosure, which has been briefly summarized above, can be obtained by reference to embodiments, some of which are shown in the accompanying drawings. However, it should be noted that the accompanying drawings show only typical embodiments of the Disclosure, as the Disclosure may also permit other equally valid embodiments, and therefore should not be considered to limit the scope of the Disclosure. Embodiments described herein are shown in the figures of the accompanying drawings as examples, not limitations, and similar reference numerals indicate similar elements. [Brief explanation of the drawing]

[0013] [Figure 1]

[0013] A processing flow diagram of a method for depositing a nanocrystalline diamond film according to one or more embodiments is shown. [Figure 2A-2E]

[0014] This shows a schematic cross-sectional view of a substrate in a processing chamber during processing according to one or more embodiments of the present disclosure. [Modes for carrying out the invention]

[0014]

[0015] Before describing some exemplary embodiments of this disclosure, it should be understood that this disclosure is not limited to the details of the construction or processing steps described below. Other embodiments of this disclosure are possible and can be practiced or implemented in various ways.

[0015]

[0016] As used herein and in the appended claims, terms such as “precursor,” “reactant,” and “reactive gas” are used interchangeably to refer to any gas species that can react with the substrate surface.

[0016]

[0017] As used in this book, the term "approximately" means "about" or "nearly," and refers to a variation of no more than ±15% of a given number or range. For example, values ​​that differ by ±14%, ±10%, ±5%, ±2%, or ±0.5% satisfy the definition of "approximately."

[0017]

[0018] As used herein, the "substrate" refers to any substrate on which film processing is performed during the manufacturing process or the surface of a material formed on a substrate. For example, the substrate surface on which the process can be performed includes materials such as silicon, silicon oxide, strained silicon, silicon on insulator (SOI), carbon-doped silicon oxide, amorphous silicon, doped silicon, germanium, gallium arsenide, glass, sapphire, and any other materials such as metals, metal nitrides, metal alloys, and other conductive materials. The substrate includes, but is not limited to, semiconductor wafers. Before, during, or after the method of the present disclosure, the substrate can be exposed to a pretreatment process to polish, etch, reduce, oxidize, hydroxylate, anneal, and / or bake the substrate surface.

[0018]

[0019] The substrate can be any substrate on which a material can be deposited, such as, for example, a silicon substrate, a III-V compound substrate, a silicon germanium (SiGe) substrate, an epi-substrate, a silicon on insulator (SOI) substrate, a display substrate (e.g., 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.

[0019]

[0020] In some embodiments, the substrate includes a dielectric. In some embodiments, the substrate includes or consists essentially of silicon. In some embodiments, the substrate includes or consists essentially of silicon oxide, silicon nitride, or silicon carbide. In some embodiments, the substrate is not a silicon substrate. In some embodiments, before being processed by the method of the present disclosure, the substrate substantially does not contain any native oxide. As used in this context, a substrate that "substantially does not contain any native oxide" contains less than 2% oxygen atoms of the surface atoms of the substrate material. In some embodiments, before being processed by the method of the present disclosure, the surface oxide of the substrate is cleaned.

[0020] In addition to direct film processing on the substrate surface itself, any of the disclosed film processing steps may be performed on an underlying layer formed on the substrate, as will be disclosed in more detail below. The term “substrate surface” is intended to include any underlying layer as the context indicates. For example, if a film / layer or partial film / layer is deposited on the substrate surface, the exposed surface of the newly deposited film / layer becomes the substrate surface.

[0021]

[0022] In one or more embodiments, the use of the term “on” in relation to a film or layer of film includes the presence of the film or layer directly on a surface (e.g., the substrate surface) and the presence of one or more underlying layers between the film or layer and the surface (e.g., the substrate surface). Thus, in one or more embodiments, the expression “on the substrate surface” is intended to include one or more underlying layers. In other embodiments, the expression “directly on” refers to a layer or film that is in contact with the surface (e.g., the substrate surface) but has no intervening layer. Thus, the expression “layer directly on the substrate surface” refers to a layer that is in direct contact with the substrate surface and has no intervening layer.

[0022]

[0023] As used herein, the term "nanocrystalline diamond" refers to a solid film of diamond grown on a substrate (e.g., silicon). In one or more embodiments, the degree of nanocrystallinity is a result of enhanced renucleation reactions in diamond growth, and the growth of diamond crystals is inhibited by variations in the surrounding environment, such as the amount of radical species, temperature, and pressure. In one or more embodiments, the nanocrystalline diamond layer is mainly composed of small nanospherical or nanocolumnar diamond crystals, with amorphous carbon typically distributed between surrounding crystals or accumulating at grain boundaries. Due to its chemical inertness, light transmittance, and good mechanical properties, nanocrystalline diamond is used as a hard mask material in semiconductor applications.

[0023]

[0024] One or more embodiments of this disclosure advantageously provide a novel method for in situ nucleation and growth of nanocrystalline diamond films. The embodiments describe the development and use of plasma and gas chemistry for substrate preparation and nucleation and growth of nanocrystalline diamond films. In one or more embodiments, no prior solution-based substrate preparation / cleaning or additional seeding methods such as sonication or mechanical scratching with nanodiamonds are used. Similarly, no special chemicals are required during the process.

[0024]

[0025] Several embodiments of this disclosure advantageously provide a method for forming nanocrystalline diamond films on oxide-rich amorphous interface layers. Without being constrained by theory, the inventors found that oxide-rich interface layers are in contrast to previously reported interface layers that are essentially SiC. Furthermore, the presence of oxide interface layers is thought to provide a branching point in the growth mechanism of NCD films, potentially enabling growth on previously unreported substrates.

[0025]

[0026] In one or more embodiments, a nanocrystalline diamond layer is formed on a substrate. The process of one or more embodiments advantageously produces a nanocrystalline diamond layer having high density, high hardness, high etching selectivity, low stress, and excellent thermal conductivity.

[0026]

[0027] Hard masks are used as etching stop layers in semiconductor processing. Ashable hard masks have a chemical composition that, once they have served their purpose, can be removed by a technique called ashing. Ashable hard masks generally consist of carbon and hydrogen, along with trace amounts of one or more additional elements (e.g., nitrogen, fluorine, boron, silicon).

[0027]

[0028] In typical applications, after etching, the hard mask is removed from the underlying layer, having fulfilled its purpose. This is generally achieved by ashing, also known as "plasma ashing" or "dry stripping," at least partially. A substrate with a hard mask to be ashing, generally a partially manufactured semiconductor wafer, is placed in a chamber under vacuum. Oxygen is then introduced and exposed to high-frequency power, which generates oxygen radicals and ions (i.e., oxygen plasma). The plasma reacts with the hard mask, oxidizing it to water, carbon monoxide, and carbon dioxide. In some cases, complete removal of the hard mask can be achieved by additional wet or dry etching after ashing, for example, when the ashingable hard mask leaves any residue that cannot be removed by ashing alone.

[0028]

[0029] Hard mask layers are often used in narrow and / or deep contact etching applications, where the photoresist may not be thick enough to mask the underlying layer. This is especially true when the critical dimensions are reduced.

[0029]

[0030] V-NAND or 3D-NAND structures are used in flash memory applications. A V-NAND device is a vertically stacked NAND structure in which numerous cells are arranged in a block-like manner. In this specification, the term "3D-NAND" refers to a type of electronic (solid-state) non-volatile computer memory in which memory cells are stacked in multiple layers. 3D-NAND memory generally includes multiple memory cells, each containing a floating-gate transistor. Conventionally, 3D-NAND memory cells include multiple NAND memory structures arranged three-dimensionally around a bit line.

[0030]

[0031] A critical step in 3D-NAND technology is slit etching. As the number of layers increases at each technology node, the thickness of the hard mask film needs to increase proportionally to withstand high-aspect-ratio etching profiles in order to control the slit etching profile. Currently, amorphous carbon (aC:H) films are used because they are hard and easy to remove after slit etching. However, amorphous carbon hard mask films have concerns about delamination and poor morphology, which can lead to the formation of pillar grooves.

[0031]

[0032] One or more embodiments of this disclosure will be described with reference to the drawings. Figure 1 is a processing flow chart of Method 10 according to one or more embodiments. Figures 2A to 2E show schematic cross-sectional views of a substrate 102 being processed by Method 10 according to one or more embodiments.

[0032]

[0033] Referring to Figures 1 and 2A-2B, a method 10 for forming a fully aggregated diamond film 120 of nanocrystals is described. In some embodiments, method 10 includes, in step 12, treating a substrate 102 with a first plasma 101 from a first plasma source 112 to form a treated substrate 104. The surface of the substrate 102 is subjected to the first plasma 101 in a first plasma treatment chamber 100 for a first plasma period T P1 The substrate 104 is exposed to and processed over a wide area.

[0033]

[0034] The first plasma processing chamber 100 may be, but is not limited to, any suitable plasma chamber having any suitable plasma source such as remote, microwave, capacitively coupled plasma (CCP), or inductively coupled plasma (ICP). In some embodiments, the flow rates and other processing parameters described below are for a 300 mm substrate. It should be understood that these parameters can be adjusted based on the size of the substrate to be processed and the type of chamber used without departing from the methods disclosed herein. In certain embodiments, the first plasma 101 includes one or more of the following: capacitively coupled plasma, inductively coupled plasma, pulsed discharge plasma, microwave plasma, hot filament, or electron cyclotron resonance plasma.

[0034]

[0035] In some embodiments, the first plasma 101 is based on empirical formula C x H y The mixture contains one or more of the following: an organic species having (where y≧x in the formula), argon (Ar), nitrogen gas (N2), carbon dioxide (CO2), or hydrogen gas (H2).

[0035]

[0036] In some embodiments, the first plasma is generated with a power of approximately 50 watts or more, approximately 100 watts or more, or approximately 150 watts or more. In one or more embodiments, the plasma treatment may be performed with any appropriate power. In one or more embodiments, the power is approximately 50 watts or more. In other embodiments, the power is in the range of approximately 50 watts to approximately 12 kW, or approximately 100 watts to approximately 10 kW, or approximately 100 watts to approximately 5 kW, or approximately 100 watts to approximately 1 kW.

[0036]

[0037] In some embodiments, the substrate 102 is maintained at a temperature in the range of about 20°C to about 600°C during the formation of the processed substrate 104.

[0037]

[0038] In some embodiments, forming the processed substrate 104 includes exposure to the first plasma 101 for at least one cycle. In some embodiments, forming the processed substrate 104 includes exposure to the first plasma 101 for a range of 1 to about 1000 cycles.

[0038]

[0039] In some embodiments, the first plasma processing chamber 100 includes a first plasma source 112 which may include one or more of the following: a showerhead, electrodes, a resonator, a linear antenna, etc. In one or more embodiments, the first plasma source 112 is positioned at a first distance D1 from the upper surface of the substrate 102. In some embodiments, the first distance D1 is 10 mm or more, 15 mm or more, 20 mm or more, or 25 mm or more.

[0039]

[0040] Although not shown in the figure, in some embodiments, step 12 forms an oxide-rich amorphous layer directly on the substrate 102. In other words, in some embodiments, the treated substrate 104 includes an oxide-rich amorphous layer. At this point in Method 10, the oxide-rich amorphous layer contains about 50 to about 70 atomic percent of oxygen. In some embodiments, the oxide-rich amorphous layer contains about 5 to about 75, about 10 to about 75, about 20 to about 70, about 35 to about 70, or about 50 to about 70 atomic percent of oxygen. At this point in Method 10, the oxide-rich amorphous layer has a thickness of about 5 nm or less, about 10 nm or less, about 20 nm or less, or about 50 nm or less.

[0040]

[0041] Referring to Figures 1 and 2C, in step 14, the treated substrate 104 is incubated with a carbon-rich gas stream 108 and a second plasma 106 to nucleate diamond particles that form a diamond nucleation layer 110 on the upper surface of the substrate 102. In some embodiments, the diamond nucleation layer 110 on the substrate 102 (or treated substrate 104) is referred to as the seeded substrate.

[0041]

[0042] In one or more embodiments, the diamond nucleus layer 110 is formed in a second plasma processing chamber 150 using a second plasma 106 generated by a second plasma source 114. In other embodiments not shown, the diamond nucleus layer 110 is formed in a first plasma processing chamber 100 using a second plasma 106 generated by a first plasma source 112. In some embodiments, the second plasma 106 may be generated by the first plasma source 112, but using a different gas (composition).

[0042]

[0043] The second plasma processing chamber 150 and the first plasma processing chamber 100 may be any suitable plasma chamber having any suitable plasma source such as remote, microwave, capacitively coupled plasma (CCP), or inductively coupled plasma (ICP), but are not limited thereto. In some embodiments, the flow rates and other processing parameters described below are for a 300 mm substrate. These parameters should be understood to be adjustable based on the size of the substrate to be processed and the type of chamber used without departing from the embodiments disclosed herein. In certain embodiments, the second plasma 106 may include one or more of the following: capacitively coupled plasma, inductively coupled plasma, pulsed discharge plasma, microwave plasma, hot filament, or electron cyclotron resonance plasma.

[0043]

[0044] In some embodiments, the gas flow 108 (and the resulting second plasma 106) contains hydrocarbons. In one or more embodiments, the hydrocarbons are of the general formula C m H n The formula has the following characteristics, where m is in the range of 1 to 120 and n is in the range of 2 to 242. In certain embodiments, the hydrocarbons are methane (CH4), ethane (C2H6), propane (C3H8), butane (C4H 10 ), pentane (C5H 12 ), Hexane (C6H 14 ), heptane (C7H 16 ), ethane (C2H4), propene (C3H6), butene (C4H8), pentene (C5H10 ), Hexene (C6H 12 ), heptane (C7H 14 ), etine (C2H2), propine (C3H4), butine (C4H6), pentine (C5H8), hexine (C6H 10 ) and heptin (C7H 12 ) one or more of the following will be selected.

[0044]

[0045] In one or more embodiments, the second plasma 106 may contain one or more of argon (Ar), nitrogen gas (N2), carbon dioxide (CO2), or hydrogen gas (H2) in addition to hydrocarbons. In one or more embodiments, the hydrocarbon-containing gas stream 108 is flowed together with one or more of argon (Ar), nitrogen gas (N2), carbon dioxide (CO2), or hydrogen gas (H2) during plasma generation. In one or more embodiments, the gas stream 108 contains 5% to 90% hydrocarbons.

[0045]

[0046] In some embodiments, the second plasma 106 is generated with a power of approximately 15 kilowatts (kW) or less, approximately 12 kW or less, approximately 10 kW or less, approximately 8 kW or less, approximately 6 kW or less, approximately 5 kW or less, or approximately 4 kW or less. In some embodiments, the gas flow 108 is ignited with a power of approximately 12 kW or less to form the second plasma 106. In some embodiments, the second plasma 106 is a pulsed plasma having a duty cycle of 90% or less, 70% or less, 65% or less, 60% or less, 55% or less, 50% or less, 45% or less, or 40% or less at a frequency in the range of approximately 20 Hz to approximately 5000 Hz, in the range of approximately 60 Hz to approximately 90 Hz, or in the range of approximately 70 Hz to approximately 80 Hz. In some embodiments, the second plasma 106 has a power of approximately 6 kW or less with a duty cycle of 50% or less at a frequency in the range of approximately 70 Hz to approximately 80 Hz. In some embodiments, the substrate 102 (or the treated substrate 104) is maintained at a temperature in the range of about 50°C to about 600°C during the formation of the diamond nucleation layer 110.

[0046]

[0047] In some embodiments, the substrate 102 (or the processed substrate 104) is incubated with the gas stream 108 and the second plasma 106 for a period ranging from 1 second to about 10 hours. In some embodiments, the substrate 102 (or the processed substrate 104) is incubated with the gas stream 108 and the second plasma 106 for a period of about 4 hours or less, about 3 hours or less, about 2 hours or less, or about 1 hour or less.

[0047]

[0048] In some embodiments, the substrate 102 (or processed 104) is positioned at a second distance D2 from the first plasma source 112 or the second plasma source 114. In some embodiments, the substrate 102 (or processed substrate 104) is positioned at a second distance D2 from the first plasma source 112 or the second plasma source 114, which is about 12 cm or less, about 10 cm or less, or about 8 cm or less. In some embodiments, the second distance is 1 cm or more. In some embodiments, the first plasma source 112 or the second plasma source 114 includes a showerhead that acts as an electrode. In some embodiments, the second plasma source 114 includes a microwave plasma source.

[0048]

[0049] Although not shown in the figures, in some embodiments, step 14 forms an oxide-rich amorphous layer directly on the substrate surface. Alternatively, in some embodiments, the oxide-rich amorphous layer formed by step 12 is also present after step 14. Regardless of when it is formed, in some embodiments, it can be said that the seeded substrate includes an oxide-rich amorphous layer. Furthermore, the oxide-rich amorphous layer is located directly on the substrate 102 between the diamond nucleation layer 110 and the substrate 102. At this point in method 10, the oxide-rich amorphous layer contains at least 5 atomic percent or at least 20 atomic percent oxygen. At this point in method 10, the oxide-rich amorphous layer has a thickness of about 50 nm or less, about 20 nm or less, about 10 nm or less, about 5 nm or less, or about 3 nm or less.

[0049]

[0050] In step 16, the nanocrystalline diamond film 118 is grown from the diamond nucleation layer 110. When used in this way, the term “grown” means that the nanocrystalline diamond film 118 is formed from the diamond nucleation layer 110, and the diamond nucleation layer 110 can be incorporated into the nanocrystalline diamond film 118. The nanocrystalline diamond film 118 can be epitaxially grown or deposited by any suitable technique known to those skilled in the art.

[0050]

[0051] In some embodiments, the nanocrystalline diamond film 118 is grown in a second plasma processing chamber using a third plasma 125. In other embodiments, the nanocrystalline diamond film 118 is grown in a first plasma processing chamber 100 using a third plasma 125. Thus, in one or more embodiments, the first processing chamber 100 and the second processing chamber 150 are the same chamber. In some embodiments, the nanocrystalline diamond film 118 is grown using one or more of the following: conduction or inductively coupled plasma, microwave plasma, pulsed discharge plasma, microwave plasma, hot filament, or electron cyclotron resonance plasma. In some embodiments, the nanocrystalline diamond film 118 is grown using microwave plasma.

[0051]

[0052] In some embodiments, the third plasma 125 includes a microwave plasma having a power of approximately 50W or more, approximately 100W or more, approximately 500W or more, approximately 1000W (1kW) or more, or approximately 3kW or more, with a duty cycle of approximately 60% or more, approximately 70% or more, or approximately 80% or more.

[0052]

[0053] In some embodiments, the substrate 102 is maintained at a temperature in the range of about 25°C to about 750°C during exposure to the third plasma 125. In some embodiments, the substrate 102 is maintained at a temperature of about 25°C or higher, about 50°C or higher, about 75°C or higher, about 100°C or higher, about 150°C or higher, about 200°C or higher, or about 250°C or higher during exposure to the third plasma 125.

[0053]

[0054] During step 16, the substrate 102 is positioned at a distance D3 from the third plasma source 130. In some embodiments, the third plasma 125 may be generated by the first plasma source 112 and / or the second plasma source 114, but using different gases (compositions), or by a different third plasma source 130. In some embodiments, distance D3 is the same as distance D2. In some embodiments, the third distance D3 is smaller than the third distance D2. In some embodiments, the substrate 102 is positioned at a distance of about 12 cm or less, about 10 cm or less, or about 8 cm or less from the third plasma source 130, or from the first plasma source 112, or from the second plasma source 114.

[0054]

[0055] Referring to Figure 2E, in one or more embodiments, after prolonged primary growth, a fully coalesced nanocrystalline diamond film 120 is formed due to the high nucleation density on the seeded substrate. In one or more embodiments, Figure 2E shows the appearance of the fully coalesced nanocrystalline diamond film 120 after method 10 is completed. The difference between the nanocrystalline diamond film 118 and the fully coalesced nanocrystalline diamond film 120 is that in the nanocrystalline diamond film 118, diamond nuclei from the diamond nucleus layer 110 grow into individual large diamond particles. However, these large diamond particles are isolated from each other. As these large diamond particles continue to grow, they eventually come into contact with adjacent particles and begin to fuse / coale with each other. This forms a filled nanocrystalline diamond film, which becomes the fully coalesced nanocrystalline diamond film 120.

[0055]

[0056] Although not shown in the figures, in some embodiments, step 16 forms an oxide-rich amorphous layer directly on the substrate surface. Alternatively, in some embodiments, the oxide-rich amorphous layer formed by step 12 or step 14 is also present after step 16. Regardless of when it is formed, in some embodiments, it can be said that the substrate contains the oxide-rich amorphous layer. Furthermore, the oxide-rich amorphous layer is located directly on the substrate 102 between the completely bonded nanocrystalline diamond film 120 and the substrate 102. At this point in Method 10, the oxide-rich amorphous layer contains at least 5 atomic%, at least 10 atomic%, at least 20 atomic%, or at least 30 atomic%, of oxygen. At this point in Method 10, the oxide-rich amorphous layer has a thickness of about 50 nm or less, about 20 nm or less, or about 10 nm or less.

[0056]

[0057] One or more embodiments of this disclosure relate to electronic devices comprising a nanocrystalline diamond film. The nanocrystalline diamond film is located directly on an oxide-rich amorphous layer at the interface, and the oxide-rich amorphous layer is located directly on a silicon substrate. In some embodiments, the electronic device is formed by a method disclosed herein.

[0057]

[0058] Spatially relative terms such as “beneath,” “below,” “lower,” “above,” and “upper” may be used here to describe the relationship between one element or feature shown in the drawing and another, for the sake of clarity. It will be understood that spatially relative terms are intended to encompass various orientations of a device in use or operation, in addition to the orientation shown in the drawing. For example, if a device in the drawing is upside down, an element described as being “below” or “directly below” another element or feature will be oriented “above” the other element or feature. Thus, the exemplary term “below” may encompass both up and down orientations. A device may be oriented in a manner other than that described (it may be rotated 90 degrees or rotated to another orientation), and the spatially relative descriptions used herein shall be interpreted accordingly.

[0058]

[0059] In the context of describing the materials and methods discussed herein (in particular in the context of the following claims), the use of “a” and “an,” “the,” and similar references should be interpreted as encompassing both singular and plural, unless otherwise indicated herein or unless the context clearly contradicts this interpretation. Enumerations of numerical ranges herein are intended merely as abbreviations to refer individually to each distinct value falling within that range, unless otherwise indicated herein, and each distinct value is incorporated into the specification as if it were individually enumerated herein. All methods described herein may be performed in any appropriate order, unless otherwise indicated herein or unless the context clearly contradicts this interpretation. Any and all examples or exemplary language provided herein (e.g., “such as”) is intended merely to better describe the materials and methods and does not limit their scope unless otherwise requested. No language herein should be interpreted as indicating an element that is not claimed as essential to the implementation of the disclosed materials and methods.

[0059]

[0060] Throughout this Specification, any reference to “one embodiment,” “a particular embodiment,” “one or more embodiments,” or “embodiment” means that the particular features, structures, materials, or properties described in relation to that embodiment are included in at least one embodiment of this Disclosure. Therefore, any other occurrences of the phrases “in one or more embodiments,” “in a particular embodiment,” “in one embodiment,” or “in an embodiment” throughout this Specification do not necessarily refer to the same embodiment of this Disclosure. In one or more embodiments, the particular features, structures, materials, or properties are combined in any suitable manner.

[0060]

[0061] While the disclosures herein are described with reference to specific embodiments, it should be understood that these embodiments are merely illustrative of the principles and applications of the disclosure. It will be obvious to those skilled in the art that various modifications and alterations can be made to the methods and apparatus of the disclosure without departing from the spirit and scope of the disclosure. Accordingly, the disclosure is intended to include modifications and alterations that fall within the scope of the appended claims and their equivalents.

Claims

1. A method for forming a nanocrystalline diamond film, The present invention provides a silicon substrate that has been treated by exposing it to a first plasma from a first plasma source, wherein the first plasma source is C such that y≧x ｘ H ｙ , carbon dioxide (CO2) ２ ), hydrogen (H ２ ), nitrogen (N ２ Exposing a silicon substrate to one or more of the following: The process involves incubating the treated substrate with a gas stream and a second plasma to nucleate diamond particles and form a seeded substrate, wherein the gas stream contains hydrocarbons, and the substrate is incubated. The seeded substrate is exposed to a third plasma having a power exceeding 50W to form a nanocrystalline diamond film. A method comprising the following, wherein, after the formation of the nanocrystalline diamond film, the nanocrystalline diamond film is located directly above an oxide-rich amorphous layer directly above the silicon substrate.

2. The aforementioned hydrocarbon is of general formula C ｍ H ｎ The method according to claim 1, wherein the formula is in the range of 1 to 120 and n is in the range of 2 to 242.

3. The gas stream further comprises one or more of carbon dioxide (CO ２ ), hydrogen (H ２ ), nitrogen (N ２ ), and argon (Ar), the method according to claim 2.

4. The method according to claim 3, wherein the gas flow comprises 5% to 90% of the hydrocarbons.

5. The method according to claim 1, wherein the processed substrate is maintained at a temperature of less than 600°C during incubation.

6. The method according to claim 1, wherein the diamond particles are maintained at a temperature in the range of 100°C to 750°C during the formation of the nanocrystalline diamond film.

7. The method according to claim 1, wherein the substrate is exposed to the first plasma at a temperature in the range of 20°C to 600°C.

8. The method according to claim 1, wherein the substrate is exposed to the first plasma at a distance of more than 1 cm.

9. The method according to claim 1, wherein when the treated substrate is incubated with the gas flow, the gas flow is located about 1 cm to 10 cm away from the upper surface of the treated substrate.

10. The method according to claim 1, wherein when the diamond particles are exposed to the second plasma, the third plasma is located less than 10 cm away from the upper surface of the substrate.

11. The method according to claim 1, wherein the oxide-rich amorphous layer has a thickness of about 50 nm or less.

12. The method according to claim 1, wherein the treated substrate includes an oxide-rich amorphous layer directly above the silicon substrate.

13. The method according to claim 12, wherein the oxide-rich amorphous layer contains about 5 atomic percent to about 70 atomic percent of oxygen.

14. The method according to claim 1, wherein the seeded substrate includes an oxide-rich amorphous layer directly above the silicon substrate.

15. A method for forming a diamond film, Exposing a treated substrate to a gas stream to nucleate diamond particles on the upper surface of the substrate, wherein the substrate includes an exposed oxide-rich amorphous layer, and the gas stream contains hydrocarbons, Exposing the diamond particles to a plasma having a power exceeding 50W to form a nanocrystalline diamond film on the upper surface of the substrate. A method comprising the above, wherein the substrate is not silicon.

16. The aforementioned hydrocarbon is of general formula C ｍ H ｎ The method according to claim 15, wherein the formula is in the range of 1 to 120 and n is in the range of 2 to 242.

17. The gas flow is carbon dioxide (CO ２ ), hydrogen (H ２ ), nitrogen (N ２ The method according to claim 16, further comprising one or more of ) and argon (Ar).

18. The method according to claim 17, wherein the gas flow comprises 5% to 90% of the hydrocarbon.

19. The method according to claim 15, wherein the oxide-rich amorphous layer has a thickness of about 50 nm or less.

20. A silicon substrate and The amorphous oxide layer directly above the silicon substrate, The nanocrystalline diamond film directly above the amorphous oxide layer and Electronic devices, including those mentioned above.

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