High bias deposition of high quality gap fillers

Abstract

Embodiments of the present disclosure generally relate to the fabrication of integrated circuits. More particularly, the implementations described herein provide techniques for depositing high-quality gap fill. Some embodiments utilize chemical vapor deposition, plasma vapor deposition, physical vapor deposition, and combinations thereof to deposit the gap fill. The gap fill is of high quality and similar in properties to bulk material of similar composition.

Description

[0001] This application is a divisional application of the invention patent application filed on June 19, 2019, with application number "201980041431.3" and invention title "High Bias Deposition of High-Quality Gap Filler". Technical Field

[0002] This disclosure generally relates to methods for depositing thin films. More specifically, this disclosure relates to a process for filling narrow trenches using a high-quality dielectric gap filler. Background Technology

[0003] The miniaturization of semiconductor circuit elements has reached commercial scales, with feature sizes of 45nm, 32nm, 28nm, and even 20nm. As dimensions continue to shrink, new challenges arise for process steps such as filling the gaps between circuit elements with multiple materials. As the width between elements continues to shrink, the gaps often become higher and narrower, making them more difficult to fill, and gap-filling materials become stuck, creating porosity and weak seams. Conventional chemical vapor deposition (CVD) techniques often experience overgrowth of material at the top of the gap before it is fully filled. This can create porosity or seams in the gap, where the deposited material is prematurely cut off due to overgrowth; the problem is sometimes referred to as "breadcrumbs."

[0004] One solution to the lumpy problem is to combine gap-filling precursors and plasma-excited precursors in a plasma-free substrate processing area to form a newly formed flowable film. The flowability of this deposition allows the film to fill gaps without seams or pores using this chemical vapor deposition technique. This chemical vapor deposition has been found to produce better gap-filling properties than spin-on glass (SOG) or spin-on dielectric (SOD) processes. While flowable film deposition via CVD has fewer lumpy problems, this technique remains unsuitable for some categories of materials.

[0005] While flowable CVD technology represents a significant breakthrough in filling high, narrow (i.e., high aspect ratio) gaps with other gap-filling materials, there remains a need for techniques that can seamlessly fill these gaps with high-quality dielectric materials. For example, previous flowable carbon-based gap fillers contained significant amounts of oxygen and silicon. These elements significantly altered the properties of carbon-based gap-filled films.

[0006] Therefore, there is a need for precursors and methods for depositing high-quality gap-filling films. Summary of the Invention

[0007] One or more embodiments of this disclosure relate to a gap filler deposition method, the gap filler deposition method comprising positioning a substrate on an electrostatic chuck within a processing space of a processing chamber. The substrate has a substrate surface including at least one feature. The at least one feature extends to a depth from the substrate surface to a bottom surface. The at least one feature has an opening width at the substrate surface defined by a first sidewall and a second sidewall. A gap filler precursor is allowed to flow into the processing space from gas distribution elements spaced apart above the electrostatic chuck, while the processing space is maintained at a pressure between about 0.5 mTorr and about 10 Torr. Plasma is generated in the processing space above the substrate by applying a first RF bias voltage to the electrostatic chuck to deposit a gap filler within the at least one feature of the substrate. The gap filler is substantially non-porous.

[0008] Additional embodiments of this disclosure relate to a gap filler deposition method, the gap filler deposition method comprising positioning a substrate over a first electrode within a processing space of a processing chamber. The substrate has a substrate surface including at least one feature. The at least one feature extends a depth from the substrate surface to a bottom surface. The at least one feature has an opening width defined by a first sidewall and a second sidewall at the substrate surface. The processing chamber further includes a second electrode positioned above the first electrode and the substrate. The second electrode has a surface including a secondary electron emission material, the secondary electron emission material including one or more of silicon-containing or carbon-containing materials. A gap filler precursor is introduced into the processing space. A first RF power is applied to at least one of the first electrode and the second electrode. A gap filler is formed within the at least one feature of the substrate. The gap filler substantially does not contain pores.

[0009] Further embodiments of this disclosure relate to a diamond-like carbon interstitial filler within a feature of a substrate. The interstitial filler has a density of approximately 1.8 g / cm³. 3 Approximately 2.5 g / cm³ 3 The density is within the range of approximately 50% to approximately 90% of sp3 hybridized carbon atoms, and the stress is less than 100 MPa. The feature extends to a depth from the surface of the substrate to the bottom surface. The feature has an opening width defined by a first sidewall and a second sidewall at the surface. The feature has a depth-to-opening width ratio greater than or equal to approximately 10:1. Attached Figure Description

[0010] Therefore, the above-described features of the invention can be understood in detail by referring to the embodiments, some of which are illustrated in the accompanying drawings. However, it should be noted that the drawings only illustrate typical embodiments of the invention and should not be considered as limiting the scope of the invention, as other equally effective embodiments are permissible.

[0011] Figure 1 A schematic diagram illustrating an example of a deposition apparatus that can use electron beam plasma technology to practice some embodiments of this disclosure;

[0012] Figure 2 A schematic diagram depicting another example of a deposition apparatus that can practice some embodiments of this disclosure using electron beam plasma technology;

[0013] Figure 3 A flowchart depicting a method for forming a gap filler according to some embodiments of this disclosure;

[0014] Figures 4A to 4B A flowchart depicting a method for forming a gap filler according to some embodiments of this disclosure;

[0015] Figure 5A and Figure 5B A cross-section of a substrate before and after processing, according to one or more embodiments of this disclosure;

[0016] Figure 6A A schematic cross-sectional view depicting a deposition system that can be used to practice some embodiments of this disclosure;

[0017] Figure 6B A schematic cross-sectional view of another deposition system that can be used to practice some embodiments of this disclosure;

[0018] Figure 7 Describing can be used Figure 6A or Figure 6B A schematic cross-sectional view of an electrostatic chuck in a device for practicing some embodiments of the present disclosure; and

[0019] Figure 8 A flowchart depicting a method for forming a high-quality gap filler in a feature of a substrate according to one or more embodiments of this disclosure is provided.

[0020] For ease of understanding, the same element symbols have been used to denote common elements in the drawings where possible. Elements and features of one embodiment are contemplated to be advantageously incorporated into other embodiments without further description. Detailed Implementation

[0021] As used in this specification and the appended claims, the terms "substrate" and "wafer" are used interchangeably to refer to the surface or portion of the surface on which the process operates. Those skilled in the art will also understand that reference to "substrate" may refer only to a portion of the substrate, unless the context clearly states otherwise. Furthermore, references to deposition on a substrate may mean both a bare substrate and a substrate having one or more films or features deposited or formed thereon.

[0022] As used herein, “substrate” refers to any substrate on which a film treatment is performed during a manufacturing process, or a material surface formed on a substrate. For example, depending on the application, substrate surfaces on which treatments can be performed include materials such as silicon, silicon oxide, strained silicon, silicon on insulator (SOI), carbon-doped silicon oxide, silicon nitride, doped silicon, germanium, gallium arsenide, glass, sapphire, and any other materials such as metals, metal nitrides, metal alloys, and other conductive materials. Substrates include, but are not limited to, semiconductor wafers. Substrates may be exposed to pretreatment processes to grind, etch, reduce, oxidize, hydroxylate (or otherwise generate or graft target chemical moieties to impart chemical functionality), anneal, and / or bake the substrate surface. In addition to performing film treatments directly on the substrate surface itself, any of the disclosed film treatment steps may also be performed in this disclosure on an underlying layer formed on the substrate (as disclosed in more detail below), and the term “substrate surface” is intended to include such an underlying layer as indicated in the context. Therefore, for example, in cases where a film / layer or part of a film / surface has already been deposited on a substrate surface, the exposed surface of the most recently deposited film / layer becomes the substrate surface. What constitutes a given substrate surface will depend on the type of film to be deposited and the specific chemicals used.

[0023] As used in this specification and the appended claims, the terms "reactive gas," "precursor," "reactant," etc., are used interchangeably to mean a gas comprising a substance that reacts with the substrate surface. For example, a first "reactive gas" may simply be adsorbed onto the surface of the substrate and may be used for further chemical reactions with a second reactive gas.

[0024] As used herein, the term “about” means approximately or approximate and, in the context of the numerical value or range described, means a variation of ±15% or less in the value. For example, values ​​differing by ±14%, ±10%, ±5%, ±2%, or ±1% would satisfy the definition of about.

[0025] The following disclosure describes a technique for depositing high-quality interstitial fillers in features of a substrate. In the following description and... Figures 1 to 8Certain details are set forth in this disclosure to provide a thorough understanding of the various embodiments thereof. Other details of well-known structures and systems often associated with plasma processing and interstitial filling deposition are not set forth in the following disclosure to avoid unnecessarily obscuring the description of the various embodiments.

[0026] Many of the details, dimensions, angles, and other features shown in the accompanying drawings are merely illustrative of particular embodiments. Therefore, other embodiments may have different details, elements, dimensions, angles, and features without departing from the spirit or scope of this disclosure. Furthermore, other embodiments of this disclosure may be practiced without some of the details described below.

[0027] The embodiments described herein will be described with reference to PECVD processes that can be performed using any suitable thin film deposition system. Examples of suitable systems include those that can be performed using DXZ. ® CENTURA processing chamber ® System, PRECISION 5000 ® System, PRECISION 5000 ® System, PRODUCER ® System, PRODUCER ® GT TM System, PRODUCER ® XP Precision TM System, PRODUCER ® SE TM System, Sym3 ® Processing chambers and Mesa™ processing chambers, all of which are available from Applied Materials, Inc., Santa Clara, California. Other tools capable of performing PECVD processes may also be suitable for benefiting from the embodiments described herein. Additionally, any system capable of performing the PECVD processes described herein may be used. The equipment described herein is illustrative and should not be construed as limiting the scope of this disclosure.

[0028] The gap filler described herein can also be deposited in a processing chamber with a multi-frequency capacitively coupled plasma (CCP) configuration surrounded by ceramic walls. External to the ceramic walls are inductively coupled coils, which can also inductively enhance the plasma. The processing chamber has a top electrode powered by one or more RF generators. The top electrode can also act as a gas distribution nozzle. Feed gases can also be injected laterally into the processing chamber to regulate film uniformity. The processing chamber further includes a bottom electrode at which the wafer is positioned. The bottom electrode is also powered by an RF generator, and the drive frequency depends on the selected deposition scheme.

[0029] In some embodiments, the gap-filling precursor is introduced into the processing chamber via a nozzle electrode or a sidewall injection device. The processing chamber typically includes a top electrode (e.g., a nozzle electrode), a bottom electrode (e.g., a base), and an ICP coil surrounding a portion of the processing chamber. An inert gas (such as Ar or He) can be used to dilute the gap-filling precursor to increase the plasma density. A stable operating pressure (e.g., from about 0.1 mTorr to several Torr) can be established in the processing chamber via a gate valve above the vacuum pump before plasma impingement. RF power is applied to at least one of the top electrode, bottom electrode, and ICP coil. Depending on the power supply scheme, the top electrode, bottom electrode, and ICP coil may be powered simultaneously, or two of them may be powered simultaneously. The applied RF frequency ranges from several hundred kHz to tens of MHz. Multiple frequencies may also be applied to the top or bottom electrode to optimize ion flux and energy incident on the substrate. After the desired deposition time, the power is turned off, and deposition is complete.

[0030] The power supply scheme for the top electrode, bottom electrode, and ICP coil can be any of the following: In some embodiments, only the top electrode is powered. The top electrode may be driven by multiple frequencies simultaneously (e.g., about 2 MHz and about 40 MHz). In some embodiments, both the top electrode and the ICP are powered. The ICP can be used as a component to further reduce the k-value, increase the deposition rate, or adjust uniformity. In some embodiments, only the bottom electrode is powered. In this configuration, the bottom electrode is driven at a high frequency (e.g., a frequency above 13 MHz, e.g., 60 MHz) or by both high and low frequencies. In some embodiments, both the bottom electrode and the top electrode are powered simultaneously. In some embodiments, both the bottom electrode and the ICP are powered simultaneously.

[0031] In some embodiments, the top electrode has an electrode surface made of a high secondary electron emission material (such as silicon or carbon). When the top electrode is bombarded with ions, the secondary electrons emitted by the ion bombardment are accelerated by the plasma sheath, thereby gaining high energy. These high-energy secondary electrons are fired downwards like an electron beam and are very effective for the ionization and dissociation of hydrocarbon molecules. To increase the collision probability, the gap between the top and bottom electrodes can be increased.

[0032] Currently, interstitial filler applications primarily utilize flowable films, which are essentially amorphous but possess properties different from those of bulk films. In many cases, bulk films exhibit superior properties compared to flowable interstitial fillers. Therefore, interstitial fillers are needed, particularly carbon (diamond-like carbon) films and other dielectric materials (e.g., Si, SiN, SiO) with properties similar to bulk materials. For diamond-like carbon materials, the bulk properties sought in interstitial fillers include, but are not limited to, high density and modulus (e.g., higher sp3 content, more diamond-like) and low stress (e.g., <-500 MPa).

[0033] Some embodiments described herein provide methods for manufacturing carbon interstitial fillers having high density (e.g., >1.8 g / cc), high modulus (e.g., >150 GPa), and low stress (e.g., <-500 MPa). The carbon interstitial fillers produced according to some embodiments described herein not only have low stress but also high sp3 carbon content.

[0034] In some embodiments, the gap-filling materials described herein can be formed by a chemical vapor deposition (plasma-enhanced and / or thermal) process using a gap-filling precursor. In some embodiments, the gap-filling precursor comprises a hydrocarbon, and the gap-filling material comprises a diamond-like carbon material. In some embodiments, the hydrocarbon is selected from the group consisting of: C2H2, C3H6, CH4, C4H8, 1,3-dimethyladamantane, bicyclo[2.2.1]hept-2,5-diene (2,5-norbornene), adamantane (C 10 H 16 norbornene (C7H) 10 (or combinations thereof). In some embodiments, the gap-filling precursor comprises a silicon-containing material, and the gap-filling material comprises a dielectric material. In some embodiments, the dielectric material comprises one or more of silicon, silicon oxide, or silicon nitride.

[0035] The interstitial filling deposition process can be performed at temperatures ranging from -50°C to 600°C. The interstitial filling deposition process can be performed in processing spaces with pressures ranging from 0.1 mTorr to 10 Torr. The interstitial filling precursor may further include any or a combination of He, Ar, Xe, N2, and H2.

[0036] In some embodiments, the gap-filling precursor may further comprise an etchant gas, such as Cl2, CF4, or NF3, to improve film quality. Plasma (e.g., capacitively coupled plasma) may be formed from the top and bottom electrodes or the side electrodes. The electrodes may be formed from a single-supply electrode, dual-supply electrodes, or more electrodes having multiple frequencies (such as, but not limited to, 350 kHz, 2 MHz, 13.56 MHz, 27 MHz, 40 MHz, 60 MHz, and 100 MHz), which are used alternately or simultaneously in the CVD system along with any or all of the reactive gases listed herein to deposit gap-filling material in features of the substrate.

[0037] In some embodiments, hydrogen radicals are fed via RPS, which leads to selective etching of sp2 hybrid carbon atoms, thereby further increasing the proportion of sp3 hybrid carbon atoms in the interstitial filler.

[0038] Figure 1 A schematic diagram depicting an example of a processing chamber 100 that can be used to practice some embodiments of this disclosure using electron beam plasma technology. The electron beam plasma chamber has a vacuum chamber body defining the processing chamber 100, which includes cylindrical sidewalls 102. The processing chamber 100 is divided into an upper chamber 100a and a lower chamber 100b by a grid filter 104. The lower chamber 100b is a drift space because there is no substantial electric field therein when no bias voltage is applied. A top plate 106 covers the upper chamber 100a and supports an electrode 108. In some embodiments, the electrode 108 is formed of a process-compatible material, such as silicon, carbon, silicon carbide, or silicon oxide. In some embodiments, the electrode 108 is formed of a metal oxide, such as aluminum oxide, yttrium oxide, or zirconium oxide. The top plate 106 and the electrode 108 may be disk-shaped. The bottom surface of the electrode 108 faces the grid filter 104 and is exposed to the internal volume of the upper chamber 100a. In some embodiments, an insulator or dielectric ring 109 surrounds the electrode 108.

[0039] In a particular embodiment, electrode 108 is formed of a carbon-containing material that can assist in providing a carbon source during the interstitial filler deposition process. Therefore, electrode 108 can be consumed after performing numerous interstitial filler deposition processes. The material removed from electrode 108 can assist in forming a carbon interstitial filling layer with a high film density by consuming the material bombarded from electrode 108. Therefore, periodic replacement of electrode 108 can be performed to ensure process reliability and repeatability.

[0040] In some embodiments, electrode 108 functions as a nozzle element for delivering process gas into process chamber 100. In some embodiments, electrode 108 has a plurality of openings 108-1 for delivering process gas into process chamber 100. Gas is supplied from an array of process gas suppliers 114 via a valve array (not shown).

[0041] A workpiece support base 110 for supporting a workpiece (e.g., substrate 111) in the lower chamber 100b has a workpiece support surface 110a facing the grid filter 104 and can be axially moved by a lifting servo 112. In some embodiments, the workpiece support base 110 includes an insulating disk 195 forming the workpiece support surface 110a, a workpiece electrode 196 inside the insulating disk 195, and a clamping voltage supply 199 connected to the workpiece electrode 196. Additionally, a base layer 194 beneath the insulating disk 195 has an internal channel 107 for circulating a heat medium (e.g., liquid) from a circulation supply 198. The circulation supply 198 can function as a radiator or a heat source.

[0042] An RF power generator 120 having a VHF frequency (e.g., 160 MHz) and a lower-power RF power generator 122 having a frequency below the VHF or HF range (e.g., in the MF or LF range, e.g., 2 MHz) are coupled to electrode 108 via an impedance matching element 124 through an RF feed conductor 123. The RF power generators 120 and 122 are typically capable of generating RF signals with frequencies from about 0.4 kHz to about 300 MHz and power between about 0 watts and about 10,000 watts. In some embodiments, the impedance matching element 124 is adapted to provide impedance matching at different frequencies of the RF power generators 120 and 122 and provides filtering to isolate the power generators from each other. The output power levels of the RF power generators 120 and 122 are independently controlled by a controller 126. Power from the RF power generators 120 and 122 is coupled to electrode 108, as will be described in detail below. In some embodiments, the top plate 106 is conductive and in electrical contact with the electrode 108, and power from the impedance matching member 124 is conducted to the electrode 108 via the top plate 106.

[0043] In some embodiments, the sidewall 102 is formed of metal and grounded. In some embodiments, the surface area of ​​the grounded inner surface inside the upper chamber 100a is at least twice the surface area of ​​the electrode 108. In some embodiments, the grounded inner surface inside the processing chamber 100 may be coated with a process-compatible material, such as silicon, carbon, silicon carbide, or silicon oxide. In alternative embodiments, the grounded inner surface inside the processing chamber 100 may be coated with a material such as aluminum oxide, yttrium oxide, or zirconium oxide.

[0044] In some embodiments, the RF power generator 120 can be replaced by two separately controlled VHF power generators 120a and 120b. VHF power generator 120a has an output frequency in the lower portion of the VHF band (e.g., 30 MHz to 150 MHz), while VHF power generator 120b has an output frequency in the upper portion of the VHF band (e.g., 150 MHz to 300 MHz). Controller 126 can control the plasma ion density by selecting the ratio between the output power levels of VHF power generators 120a and 120b. With the two VHF power generators 120a and 120b, the radial plasma homogeneity in the upper chamber 100a can be controlled by selecting the gap (the distance between electrode 108 and grid filter 104) of the upper chamber 100a, such that the lower VHF frequency generates a radially high plasma ion density at its edges in the upper chamber 100a, and the upper VHF frequency generates a radially high plasma ion density at its center. With this selection, the power levels of the two VHF power generators 120a and 120b are then set to a ratio that optimizes the uniformity of the radial distribution of plasma ion density.

[0045] In some embodiments, the top plate 106 serves as a support for the electrode 108 and includes an insulating layer 150 containing a clamping electrode 152 facing the electrode 108. A DC clamping voltage supplier 154 is coupled to the clamping electrode 152 via a feed conductor 155 for electrostatically clamping the electrode 108 to the top plate 106. A DC blocking capacitor 156 may be connected in series with the output of an impedance matching element 124. A controller 126 controls the DC clamping voltage supplier 154. In some embodiments, an RF feed controller 123 from the impedance matching element 124 may be connected to the electrode support or the top plate 106, rather than directly to the electrode 108. In this embodiment, RF power from the RF feed conductor 123 may be capacitively coupled from the electrode support to the electrode 108. In some embodiments, an upper gas injector 130 supplies process gas to the upper chamber 100a via a first valve 132. In some embodiments, the lower gas injector 134 supplies process gas to the lower chamber 100b via a second valve 136. Gas is supplied from an array of process gas suppliers 138 via an array of valves 140, which may include, for example, a first valve 132 and a second valve 136. In some embodiments, the type of gas and the gas flow rate to the upper chamber 100a and the lower chamber 100b are independently controllable. The controller 126 can control the array of valves 140. In some embodiments, an inert gas is supplied to the upper chamber 100a and the process gas is supplied to the lower chamber 100b. The inert gas flow rate can be selected to substantially prevent gas convection or diffusion from the lower chamber 100b to the upper chamber 100a, thereby providing substantial chemical isolation of the upper chamber 100a.

[0046] In some embodiments, plasma can be generated in the upper chamber 100a through various bulk and surface processes, including high-energy particle bombardment of the inner surface of the top electron emission electrode 108. The ion bombardment energy of electrode 108 and the plasma density are functions of both RF power generators 120 and 122. The ion bombardment energy of electrode 108 can be substantially controlled by a lower frequency power from RF power generator 122, and the plasma density in the upper chamber 100a can be substantially controlled (enhanced) by VHF power from RF power generator 120. High-energy secondary electrons can be emitted from the inner surface of electrode 108. The high-energy electron flux from the emission surface can include an electron beam and can have a direction substantially perpendicular to the inner surface of electrode 108, and a beam energy approximately equal to the ion bombardment energy of electrode 108, typically ranging from about 10 eV to 5000 eV, such as at least greater than 100 eV. The collision cross-section of different processes depends on the electron energy. At low energies, the cross-section used for excitation (and dissociation in molecular gases) is larger than the cross-section used for ionization, while the opposite is true at high energies. Multiple RF power levels can be advantageously selected for various inelastic electron collision processes.

[0047] In some embodiments, a side window 170 in the sidewall 102 faces the upper chamber 100a and is formed of a material (e.g., quartz or alumina) through which RF power can be inductively coupled. An inductor antenna 172 surrounds the side window 170 and is driven by an optional RF power generator 174 via an impedance matching element 176. The RF power generator 174 applied to the inductor antenna 172 is controlled between approximately 200 watts (W) and approximately 10 kilowatts. The frequency of the inductively coupled power applied to the inductor antenna 172 can be between 2 MHz and approximately 13 MHz. A remote plasma source 197 can introduce plasma material into the lower chamber 100b. In embodiments with the RF power generator 174 and the inductor antenna 172, the plasma density in the upper chamber 100a can be substantially controlled (enhanced) by the RF power from the RF power generator 174. In one example, an RF power generator 174 and an inductor antenna 172 can assist in providing bombardment power to sputter material from the electrode 108, thus assisting in placing the material onto the surface of the substrate 111 disposed on the workpiece support base 110.

[0048] In some embodiments, the grid filter 104 is flat and disk-shaped and can be coaxial with the sidewall 102. The grid filter 104 forms an array of a plurality of openings 104-1. In some embodiments, the axial thickness T of the grid filter 104 and the diameter "d" of the plurality of openings 104-1 are selected to facilitate the flow of high-energy guided electrons through the grid filter 104 while preventing the flow of non-beam (low-energy) electrons and plasma ions through the grid filter 104, and the ratio of the grid filter aperture area to the total grid filter area is maximized. The high-energy electron flux (electron beam) can pass through the grid filter 104 to the lower chamber 100b, and plasma can be generated in the lower chamber 100b by various electron impact processes.

[0049] The plasma generated by the electron beam in the lower chamber 100b may have different characteristics than the plasma in the upper chamber 100a. A grid filter 104 may act as a filter to substantially electrically isolate the upper chamber 100a and the lower chamber 100b from each other. In some embodiments, the grid filter 104 is formed of a conductive or semiconductor material and may be grounded or electrically floating. In some embodiments, the grid filter 104 is formed of a non-conductive material. In some embodiments, the grid filter 104 may be coated with a process-compatible material, such as silicon, carbon, silicon carbide, or silicon oxide. In some embodiments, the grid filter 104 may be coated with a material such as alumina, yttrium oxide, or zirconium oxide. In some embodiments, the plasma generated in the upper chamber 100a may have a high electron density and / or a high electron temperature, and contain high-energy ions impacting the electrode 108.

[0050] At least a portion of the electron beam, consisting of the secondary electron flux emitted from electrode 108 due to high-energy ion bombardment at the electrode surface, propagates through grid filter 104 and into lower chamber 100b, thereby generating a low-electron-temperature plasma in lower chamber 100b with a plasma density dependent on beam energy and flux, as well as other factors such as pressure and gas composition. Upon exiting the plasma region of lower chamber 100b, the high-energy beam electrons may impact substrate 111 or workpiece support base 110. The remaining plasma readily discharges any surface charge resulting from the electron beam flux.

[0051] In some embodiments requiring higher electron beam flux or higher electron beam density, the grid filter 104 can be removed or eliminated, such as... Figure 2 As shown, this facilitates the faster arrival of the secondary electron beam flux emitted from electrode 108 at substrate 111 or workpiece support base 110. Alternatively, the grid filter 104 may be removed or eliminated in processing chamber 100 for any process considerations and needs, such as... Figure 2 As shown in the image.

[0052] In some embodiments, an electronegative or electron-adsorbing gas, such as chlorine, is supplied to the chamber, RF and / or VHF power is applied to electrode 108, optionally RF power is applied to inductor antenna 172, and optionally remote plasma source (RPS) power is applied to remote plasma source (RPS) 197, generating plasma in upper chamber 100a and forming an accelerating voltage on electrode 108 relative to ground and relative to the plasma. The resulting high-energy ion bombardment of electrode 108 generates secondary electron emission from the electrode surface, which constitutes the electron beam flux from the electrode surface. Grid filter 104 allows at least a portion of the electron beam to propagate through grid filter 104 and into lower chamber 100b, while preventing at least a portion of non-beam electrons and plasma ions from passing through grid filter 104, thereby generating a low-electron-temperature plasma in lower chamber 100b. The low electron temperature plasma obtained in the lower chamber 100b in an electronegative gas (such as chlorine) can produce a highly electronegative plasma with a negative ion density that is much higher than the electron density and reaches the density of positive ions. This plasma is commonly referred to as an ion-ion plasma.

[0053] Optionally, a substantially axially oriented magnetic field, substantially parallel to the electron beam, can be used to aid in guiding the electron beam, thereby improving electron beam delivery through the upper chamber 100a, the grid filter 104, and / or the lower chamber 100b. A low-frequency bias voltage or an arbitrary waveform with a low repetition frequency can be applied to the workpiece support base 110 (e.g., to the workpiece electrode 196) to selectively or alternately extract positive and / or negative ions from the plasma and accelerate those ions to desired levels to impact the surface of the substrate 111 for etching, cleaning, deposition, or other material modification. (a) Free radicals generated in the upper chamber 100a, (b) free radicals generated by the electron beam in the lower chamber 100b, (c) free radicals generated by applying a bias voltage to the workpiece support base 110, or (d) free radicals generated by a remote plasma source (RPS) 197 can convection or diffuse to the substrate 111 and participate in reactions on the workpiece surface.

[0054] In some embodiments, a relatively inert gas, such as helium or argon, is supplied to the upper chamber 100a, and an electronegative or electron-adsorbing gas (such as sulfur hexafluoride or carbon fluoride or the like) flows into the lower chamber 100b. RF and / or VHF power is applied to the electrode 108, optionally to the inductor antenna 172, and optionally to the remote plasma source 197, generating plasma in the upper chamber 100a and forming an accelerating voltage on the electrode 108 relative to ground and relative to the plasma. The resulting high-energy ion bombardment of the electrode 108 generates secondary electron emission from the electrode surface, which constitutes the electron beam flux from the electrode surface. A grid filter 104 allows at least a portion of the electron beam to propagate through the grid filter 104 and into the lower chamber 100b, while preventing at least a portion of non-beam electrons and plasma ions from passing through the grid filter 104, thereby generating a low-electron-temperature plasma in the lower chamber 100b.

[0055] The low electron temperature plasma obtained in the electronegative gas in the lower plasma chamber can produce a highly electronegative plasma with a negative ion density that is much higher than the electron density and reaches the density of positive ions. This is usually called ion-ion plasma.

[0056] In some embodiments, the grid filter 104 is a gas distribution plate having an internal gas passage 105a and a gas injection outlet 105b. The internal gas passage 105a may be coupled to an array of valves 140.

[0057] In some embodiments, the RF bias power generator 142 is coupled to the workpiece electrode 196 of the workpiece support base 110 via an impedance matching member 144. In another embodiment, a waveform customization processor 147 may be connected between the output of the impedance matching member 144 and the workpiece electrode 196. The waveform customization processor 147 modifies the waveform generated by the RF bias power generator 142 to a desired waveform. The waveform customization processor 147 controls the ion energy of the plasma near the substrate 111. In some embodiments, the waveform customization processor 147 generates a waveform in which the amplitude is maintained at a level corresponding to the desired ion energy level during a specific portion of each RF cycle. The controller 126 can control the waveform customization processor 147.

[0058] In some embodiments, an RF power generator 146 having a VHF or HF frequency (e.g., 11 MHz to 60 MHz) and an RF power generator 148 having a frequency below the VHF or HF range (e.g., in the MF or LF range, e.g., 0.4 kHz to 10 MHz) are coupled to a workpiece electrode 196 via an impedance matching element 144. The RF power generators 146 and 148 are typically capable of generating RF signals with frequencies from about 0.4 kHz to about 300 MHz and power between about 0 watts and about 10,000 watts. In some embodiments, the RF power generators 146 and 148 are RF bias power generators. In some embodiments, the RF power generators 146 and 148 are RF power supply power generators. In some embodiments, the impedance matching element 124 is adapted to provide impedance matching at different frequencies of the RF power generators 146 and 148 and provides filtering to isolate the power generators from each other. The output power levels of the RF power generators 146 and 148 are independently controlled by a controller 126. As will be described herein, power from RF power generators 146, 148 is coupled to workpiece electrode 196. As previously discussed, a VHF generator may be used.

[0059] In some embodiments, a magnet 160 surrounds a processing chamber 100. In some embodiments, the magnet includes a pair of magnets 160-1 and 160-2 adjacent to an upper chamber 100a and a lower chamber 100b, respectively. In some embodiments, the pair of magnets 160-1 and 160-2 provide an axial magnetic field suitable for confining an electron beam propagating from the upper chamber 100a to the lower chamber 100b.

[0060] In some embodiments, the flow of high-energy electrons to substrate 111 is blocked by a magnetic field having a predominantly radial component (i.e., transverse to the direction of electron beam flow) in the region between grid filter 104 and substrate 111. This magnetic field may be generated by one of magnets 160-1 or 160-2, or by another magnet or another set of magnets.

[0061] In some embodiments, the top plate 106 includes an internal channel 178 for conducting a heat-conducting liquid or medium within the top plate 106. The internal channel 178 is connected to a heat medium circulation supply 180. The heat medium circulation supply 180 acts as a heat sink or heat source. The mechanical contact between the electrode 108 and the top plate 106 is sufficient to maintain high thermal conductivity between the electrode 108 and the top plate 106. Figure 1 In the embodiment shown, the force of the mechanical contact is adjusted by the electrostatic clamping force provided by the DC clamping voltage supply 154.

[0062] Figure 3A flowchart depicting a method 300 for forming a gap filler in a substrate feature according to one or more embodiments of this disclosure. Figures 4A to 4B This is a cross-sectional view of the substrate, illustrating a sequence of gap fillers formed in the substrate features according to method 300.

[0063] Method 300 begins at operation 310 by providing substrate 111 to a processing chamber (such as, Figure 1 or Figure 2 The processing chamber 100 is depicted in the text. A suitable substrate is described elsewhere in this disclosure.

[0064] At operation 320, gap-filling precursor is supplied to processing chamber 100 to prepare for the formation of gap filler in the substrate features. The gap-filling precursor can be supplied from processing gas supplier 138 to gas injectors 130, 134 via an array of valves 140, thereby flowing into processing chamber 100.

[0065] In some embodiments, the interstitial filling precursor comprises hydrocarbons. Suitable hydrocarbons are discussed elsewhere in this disclosure. Additional suitable hydrocarbon compounds include alicyclic hydrocarbons and aromatic hydrocarbons.

[0066] For example, alicyclic hydrocarbons include cyclopropane, cyclobutane, cyclopentane, cyclopentadiene, toluene, etc. Aromatic hydrocarbons include benzene, styrene, toluene, xylene, pyridine, ethylbenzene, acetophenone, methyl benzoate, phenyl acetate, phenol, cresol, furan, etc. Additionally, α-terpinene, umbelliferene, 1,1,3,3-tetramethylbutylbenzene, t-butyl ether, t-butylethylene, methyl methacrylate, and tert-butylfurfuryl ether may be suitable.

[0067] In some embodiments, the hydrocarbon is selected from the following: propylene, acetylene, ethylene, propylene, butene, toluene, α-terpinene. In some embodiments, the hydrocarbon is selected from the following: C2H2, C3H6, CH4, C4H8, 1,3-dimethyladamantane, bicyclo[2.2.1]hept-2,5-diene (2,5-norbornene), adamantane (C 10 H 16 norbornene (C7H) 10 ), or combinations thereof.

[0068] In some embodiments, multiple hydrocarbon compounds may be mixed and supplied to the processing chamber as gap-filling precursors. Two or more hydrocarbon compounds may be used to deposit the gap-filling material.

[0069] In some embodiments, the hydrocarbon includes methane (CH4) or is substantially composed of methane (CH4). In some embodiments, the interstitial filling precursor includes methane and at least one of propylene, acetylene, or ethylene.

[0070] In some embodiments, a gap-filling precursor (such as methane) may be supplied to the gas mixture at a rate between about 50 sccm and about 1000 sccm. An inert gas (such as Ar or He) may be supplied to the gas mixture at a rate between about 10 sccm and about 1000 sccm. Hydrogen may be supplied to the gas mixture at a rate between about 100 sccm and about 500 sccm. Oxygen may be supplied to the gas mixture at a rate between about 0 sccm and about 200 sccm. Nitrogen may be supplied to the gas mixture at a rate between about 0 sccm and about 400 sccm. Additionally, additional hydrocarbons may be supplied to the gas mixture at a flow rate between about 100 sccm and about 2000 sccm.

[0071] In some embodiments, adjustable flow rates and types can be controlled and supplied to the processing chamber 100 from different locations (such as the upper gas injector 130 or the lower gas injector 134 and the electrodes) to maximize radical dissociation and plasma density below or above the grid filter 104. For example, if a higher plasma density is required in the upper chamber 100a to increase the beam electron flux, an inert gas (such as Ar or He) can be supplied via the upper gas injector 130, which can promote electrode bombardment and reduce the molecular gas density near the electrode 108 to increase the local plasma density and beam electron flux. Conversely, when hydrogen molecule dissociation is required (e.g., to increase the purity of the resulting membrane), a hydrogen-containing gas can be supplied via the upper gas injector 130 to reduce the local plasma density but promote hydrogen radical formation to remove impurities in the processing chamber and the resulting interstitial filler.

[0072] Optionally, at operation 330, the pressure in the processing chamber 100 is stabilized for a predefined RF turn-on delay period. The predefined RF turn-on delay period is a fixed time delay defined as the time between the introduction of the gap-filling precursor into the processing chamber 100 during operation 340 and the impact or generation of plasma. Any suitable fixed time delay can be used to achieve the desired conditions. Typically, the length of the RF turn-on delay period is chosen such that the gap-filling precursor does not begin to thermally decompose or substantially thermally decompose in the processing chamber 100. The process of operation 330 can be performed simultaneously with, sequentially with, or partially overlap with the processes of operations 320 and 340.

[0073] In this embodiment, the gap-filling precursor may be introduced into the processing chamber 100 for a relatively long time, such as between about 5 seconds and about 30 seconds, for example, about 15 seconds, the time of which may vary depending on the size of the substrate. It is believed that the flow of the gap-filling precursor prior to impact with the plasma provides sustained thermal and pressure stability to the processing chamber 100. In some embodiments, prior to impact with the RF plasma in operation 340, the gap-filling precursor then flows into the processing chamber 100 for about 0.5 seconds to about 5 seconds, for example, about 1 second to about 2 seconds (the flow time may vary as long as the flow is long enough for the gap-filling precursor to begin reaching the internal volume of the processing chamber 100).

[0074] At operation 340, after the gap-filling precursor is supplied to the processing chamber, RF power is supplied to at least one of the upper electrode (e.g., electrode 108), the lower electrode (e.g., workpiece electrode 196), and / or the inductor antenna (e.g., inductor antenna 172). At operation 340, after the gas mixture is supplied to the processing chamber, a first RF power supply may be generated from RF power generators 120, 122 and applied to electrode 108 to generate plasma and a secondary electron beam. The secondary electron beam from electrode 108 may generate cold plasma, such as at a temperature below 100 degrees Celsius, which irradiates the surface of the substrate to form a gap-filling material thereon. Alternatively, a second optional RF power supply may be applied to inductor antenna 172 via RF power generator 174 to increase inductive coupling power. The resulting inductively coupled power can increase the free radical flux of the substrate and increase the incident ion flux (or beam flux) of electrons in the upper chamber 100a, thereby generating a high-density beam of electrons. The inductively coupled power also reduces the sheath voltage on electrode 108, thereby reducing beam energy. Additionally, a third optional RF power can be applied to the workpiece electrode 196 to optimize the ion flux and the energy incident on the substrate. This third RF power can be generated by RF power generators 146, 148 and / or an additional RF bias power generator 142.

[0075] The second power source (e.g., inductively coupled power) generated from the RF power generator 174 and applied to the inductor antenna 172 is typically controlled between about 1 kW and about 10 kW. The frequency of the inductively coupled power applied to the inductor antenna 172 can be between 2 MHz and about 13 MHz. In some embodiments, the inductively coupled power can be eliminated and optionally applied, if necessary. A process pressure between, for example, 20 mTorr and about 20 Torr can also be used to form the gap filler. It is believed that the electron beam plasma, together with the secondary electron beam utilized during the deposition process, can provide high ion bombardment, which can enhance ion dissociation and the energy of the electron beam from the gas mixture, to form a gap filler with a robust film structure.

[0076] In some embodiments, during operation 340, power is supplied only to the upper electrode (e.g., electrode 108). For example, a first RF power source generated from at least one of RF power generators 120, 120a, 120b, 122 is applied to electrode 108 and controlled within a range of 1 kW to about 10 kW. It should be noted that the frequencies of the RF power generators 120, 120a, 120b, 122 may be between 0.4 MHz and about 300 MHz. In this example, power is applied only to the upper electrode (e.g., not to the lower electrode (e.g., workpiece electrode 196) or the inductor antenna (e.g., inductor antenna 172)). In some embodiments, the frequency applied to the upper electrode is between 0.4 MHz and about 300 MHz. In some embodiments, a high frequency (e.g., between about 11 MHz and 60 MHz) is applied to the upper electrode. In some embodiments, a low frequency (e.g., between about 0.4 kHz and 10 MHz) is applied to the upper electrode. In some embodiments, multiple frequencies are applied to the upper electrode (e.g., 2 MHz from the low-frequency RF power generator 122 and 40 MHz from the VHF power generator 120a).

[0077] In some embodiments, both the upper electrode (e.g., electrode 108) and the inductor antenna (e.g., inductor antenna 172) are powered during operation 340. For example, a first RF power source generated from at least one of RF power generators 120, 120a, 120b, 122 is applied to the upper electrode and controlled within a range of 1 kW to about 10 kW, and a second RF power source is applied to the inductor antenna and controlled within a range of about 1 kW to about 10 kW. In this example, power is applied to both the upper electrode and the inductor antenna (e.g., no power is applied to the lower electrode (e.g., workpiece electrode 196)). In some embodiments, the frequency applied to the upper electrode is between about 0.4 MHz and about 300 MHz, and the frequency applied to the inductor antenna is between about 2 MHz and about 13 MHz. In some embodiments, a high frequency (e.g., between about 11 MHz and 60 MHz) is applied to the upper electrode, and the frequency applied to the inductor antenna is between about 2 MHz and about 13 MHz. In some embodiments, a low frequency (e.g., between about 0.4 kHz and 10 MHz) is applied to the upper electrode, and the frequency applied to the inductor antenna is between about 2 MHz and about 13 MHz. In some embodiments, multiple frequencies are applied to the upper electrode (e.g., 2 MHz from the low-frequency RF power generator 122 and 40 MHz from the VHF power generator 120a), and the frequency applied to the inductor antenna is between about 2 MHz and about 13 MHz. Without being bound by theory, it is believed that ICP can be used to increase the deposition rate and adjust the uniformity of the deposited gap filler.

[0078] In some embodiments, during operation 340, power is supplied only to the lower electrode (e.g., workpiece electrode 196). In embodiments where the lower electrode is powered, the drive frequency may include a high-frequency component. For example, a first RF power (biased or supplied) generated from at least one of RF power generators 146, 148 and / or an additional RF bias power generator 142 is applied to the lower electrode and controlled within a range of 1 kW to about 10 kW. It should be noted that the frequencies of the RF power generators 146, 148 and the RF bias power generator 142 may be between 0.4 MHz and about 300 MHz. In this example, power is applied only to the lower electrode (e.g., not to the upper electrode (e.g., electrode 108) or the inductor antenna (e.g., inductor antenna 172)). In some embodiments, the frequency applied to the lower electrode is between 0.4 MHz and about 300 MHz. In some embodiments, a high frequency (e.g., between about 11 MHz and 60 MHz) is applied to the lower electrode. In some embodiments, multiple frequencies are applied to the lower electrode (e.g., 2 MHz from RF power generator 148 and 40 MHz from RF power generator 146).

[0079] In some embodiments, during operation 340, both the upper electrode (e.g., electrode 108) and the lower electrode (e.g., workpiece electrode 196) are simultaneously powered using any of the aforementioned conditions. For example, RF power generated from at least one of RF power generators 120, 120a, 120b, 122 is applied to the upper electrode and controlled within a range of 1 kW to about 10 kW, and a second RF power (bias or power supply) is applied to the workpiece electrode 196 and controlled within a range of about 1 kW to about 10 kW. In this example, power is applied to both electrode 108 and workpiece electrode 196 (e.g., no power is applied to the inductor antenna (e.g., inductor antenna 172)). In some embodiments, the frequency applied to electrode 108 is between about 0.4 MHz and about 300 MHz, and the frequency applied to workpiece electrode 196 is between about 0.4 MHz and about 300 MHz. In some embodiments, multiple frequencies are applied to electrode 108 and workpiece electrode 196 (e.g., 2 MHz from a low-frequency RF power generator and 40 MHz from a VHF power generator).

[0080] In some embodiments, both the inductor antenna (e.g., inductor antenna 172) and the lower electrode (e.g., workpiece electrode 196) are powered during operation 340. In this example, power is applied to both the inductor antenna and the workpiece electrode 196 (e.g., no power is applied to the upper electrode (e.g., electrode 108)). In some embodiments, the frequency applied to the inductor antenna 172 is between about 2 MHz and about 12 MHz and is controlled within the range of 1 kW to about 10 kW, and the frequency applied to the workpiece electrode 196 is between about 0.4 MHz and about 300 MHz and is controlled within the range of about 1 kW to about 10 kW.

[0081] In some embodiments, multiple frequencies are applied to at least one of the inductor antenna 172 and the workpiece electrode 196 (e.g., 2 MHz from a low-frequency RF power generator and 40 MHz from a VHF power generator).

[0082] In some embodiments, the upper electrode (e.g., electrode 108), the lower electrode (e.g., workpiece electrode 196), and the inductor antenna (e.g., inductor antenna 172) are powered during operation 340.

[0083] During operation 340, the substrate temperature can be controlled between room temperature (e.g., 20 degrees Celsius) and approximately 1000 degrees Celsius. During operation 340, the spacing between the substrate and the nozzle can be controlled between approximately 1000 mils and approximately 15000 mils. During operation 340, the process pressure can be maintained between, for example, 0.1 millitors and approximately 20 torr.

[0084] At operation 350, after performing a deposition process by means of process parameters adjusted at operation 340, a gap filler is then formed in the substrate features. In some embodiments, the gap filler formed as described herein is configured to have a density between about 1.5 g / cc and about 2.0 g / cc. In some embodiments, the gap filler has a stress of 100 MPa or less.

[0085] Embodiments of this disclosure include methods for depositing interstitial fillers using a combination of plasma-initiated CVD and physical vapor deposition (PVD). The density, hardness, and stress of the deposited interstitial filler can be modulated by the relative weights of the CVD and PVD components.

[0086] refer to Figure 1 and Figure 2The top electrode (e.g., electrode 108) is driven by one or more RF generators and optionally acts as a gas distribution nozzle. The surface of the top electrode includes carbon portions, and carbon atoms are sputtered and deposited on the wafer surface during the PVD component as the plasma sheath accelerates the ions. The bottom electrode (e.g., workpiece electrode 196) is also powered via an RF generator. If the feed gas contains hydrocarbon gases, any RF power applied to the top and / or bottom electrodes will dissociate the hydrocarbon gases, thus generating the CVD component. One advantage of adding bias RF power to the CVD component is that hydrocarbon ions can be accelerated to the wafer surface and implanted into the carbon layer to increase the carbon film density and hardness. Strong ion bombardment also helps reduce stress and form crosslinks between the PVD and CVD layers, thereby improving the film morphology. However, if only top electrode RF power is present, the deposited film is typically soft and low in density.

[0087] In some embodiments of this disclosure, the gap-filling precursor is introduced into the processing chamber via a nozzle electrode or a sidewall injection device. An inert gas (such as Ar or He) can be used to dilute the gap-filling precursor to increase the plasma density. A stable operating pressure (e.g., from about 0.1 mTorr to several Torr) can be established in the processing chamber before plasma impingement via a gate valve above the vacuum pump. RF power is applied to at least one of the top electrode, bottom electrode, and ICP coil. As previously described herein, depending on the power supply scheme, the top electrode, bottom electrode, and ICP coil may be powered simultaneously, or two of these three may be powered simultaneously. The applied RF frequency ranges from several hundred kHz to tens of MHz. Multiple frequencies may also be applied to the top or bottom electrode to optimize ion flux and energy incident on the substrate.

[0088] After the required CVD deposition time, the interstitial filling precursor can be stopped, and inert gas continues to flow into the chamber. A stable operating pressure (0.1 mTorr to tens of mTorr) can be established via a gate valve above the vacuum pump. Typically, PVD process pressures are extremely low (e.g., between about 1 mTorr and about 10 mTorr) to maximize ion energy. RF power can be applied to both the upper and lower electrodes during PVD deposition. Bottom RF power may be absent during PVD deposition. The top electrode can be powered by multiple RF frequency sources to maximize sputtering yield. A magnetic field can be used to further enhance plasma density at low pressure, thereby increasing the carbon sputtering rate. The bottom electrode can be powered to introduce moderate ion bombardment to densify the film and crosslink the PVD layer to the CVD layer. In RF sputtering schemes, the deposited film typically does not have particle problems. Repeat the PVD and CVD processes until the required amount of interstitial filler has been deposited. A deposition sequence of PVD followed by CVD or CVD followed by PVD can be used.

[0089] In some embodiments, PVD and CVD processes are performed simultaneously. In some embodiments, the CVD film may also be deposited on the carbon target surface on the top electrode, thereby hindering the sputtering process. In some embodiments, an inert purge gas flows in through the top electrode or is injected peripherally into the upper portion of the chamber (e.g., upper chamber 100a), and the carbon source gas is injected into the lower portion of the chamber (lower chamber 100b). This minimizes the back diffusion of the carbon source gas to the top electrode, thereby reducing carbon film deposition on the top electrode surface.

[0090] In some embodiments, during the CVD process, the powered top electrode also emits secondary electrons due to ion bombardment. These secondary electrons are accelerated by a plasma sheath and have energies in the range of hundreds of eV to keV. Since the electron impact ionization cross-section of hydrocarbon gases typically peaks at hundreds of eV, secondary electrons can significantly promote hydrocarbon gas ionization, thereby promoting an increase in film density. Therefore, multiple RF frequencies can be applied to the top electrode to optimize the secondary electron emission yield while maintaining the sheath voltage at around hundreds of eV.

[0091] An oxygen plasma cleaning process can be performed between the CVD and PVD steps to remove a deposited film from the surface of the upper electrode, which may have been deposited during the CVD process. Thus, the sputtering process begins with cleaning the carbon surface. The oxygen plasma can be formed by flowing an oxygen-containing gas (and optionally in an inert gas) into the processing chamber. The oxygen-containing gas can be selected from the group consisting of N2O, O2, O3, H2O, and combinations thereof. The optional inert gas can be selected from the group consisting of helium, argon, and combinations thereof. During the oxygen plasma cleaning process, RF power is supplied to the upper electrode (e.g., electrode 108) and / or an inductive antenna (e.g., inductive antenna 172).

[0092] In some embodiments of the oxygen plasma cleaning process, RF power generated from at least one of RF power generators 120, 120a, 120b, and 122 is applied to electrode 108 and controlled within a range of 1 kW to about 10 kW. It should be noted that the frequencies of the RF power generators 120, 120a, 120b, and 122 can be between 0.4 MHz and about 300 MHz. In some embodiments using a second RF power source, the second RF power (e.g., inductively coupled power) generated from RF power generator 174 and applied to coil antenna 172 is typically controlled between about 1 kW and about 10 kW. The frequency of the inductively coupled power applied to coil antenna 172 can be between 2 MHz and about 13 MHz. The oxygen plasma cleaning process can also be performed using, for example, a process pressure between 20 mTorr and about 20 Torr. The oxygen plasma cleaning process can be performed for a time period sufficient to remove residues from the surface of electrode 108.

[0093] Figures 4A to 4B A flowchart depicts one embodiment of a method 500 for forming a gap filler according to some embodiments described herein.

[0094] Method 500 begins at operation 510 by providing substrate 111 into a processing chamber, such as, Figure 1 or Figure 2 In the electron beam plasma processing chamber 100 depicted herein, the substrate 111 may have a substantially flat surface, a non-flat surface, or a structure formed thereon.

[0095] At operation 520, a gap-filling precursor is supplied to processing chamber 100 to prepare for the formation of a gap filler on substrate 111 via a chemical vapor deposition (CVD) process. In some embodiments, the gap-filling precursor may be supplied from processing gas supplier 138 to gas injectors 130, 134 via an array of valves 140, thereby flowing into processing chamber 100. In some embodiments, the gap-filling precursor may be supplied from processing gas supplier 114 to flow into electrode 108.

[0096] The gap-filling precursor may include hydrocarbons and inert gases. The hydrocarbons have been described elsewhere in this disclosure.

[0097] In some embodiments, adjustable flow rates and types can be controlled and supplied to the processing chamber 100 from different locations (such as the upper gas injector 130 or the lower gas injector 134, electrode 108) to maximize free radical dissociation and plasma density below or above the grid filter 104. For example, if a higher plasma density is required in the upper chamber 100a to increase the beam electron flux, an inert gas (such as Ar or He) can be supplied via the upper gas injector 130, which can promote electrode bombardment and reduce the molecular gas density near the electrode 108 to increase the local plasma density and beam electron flux. Conversely, when hydrogen molecule dissociation is required (e.g., to increase the purity of the resulting membrane), a hydrogen-containing gas can be supplied via the upper gas injector 130 to reduce the local plasma density but promote hydrogen free radical formation to remove impurities in the processing chamber and the resulting interstitial filler.

[0098] Optionally, similar to operation 330, at operation 530, the pressure in the processing chamber is stabilized for a predefined RF turn-on delay period. Any suitable fixed time delay can be used to achieve the desired condition. The process of operation 530 may be performed simultaneously with, sequentially with, or partially overlap with the processes of operations 520 and 540. In some embodiments, the pressure is stabilized to a pressure from about 0.1 mTorr to about 5 Torr.

[0099] In this embodiment, the gap-filling precursor may be introduced into the processing chamber 100 for a relatively long time, such as between about 5 seconds and about 30 seconds, for example, about 15 seconds, the time of which may vary depending on the size of the substrate. It is believed that the flow of the gap-filling precursor prior to impact with the plasma provides sustained thermal and pressure stability to the processing chamber 100. In some embodiments, the gap-filling precursor is introduced into the processing chamber 100 for about 0.5 seconds to about 5 seconds, for example, about 1 second to about 2 seconds, prior to impact with the RF plasma in operation 540 (the flow time may vary as long as the flow is long enough for the gap-filling precursor to begin reaching the processing chamber 100).

[0100] At operation 540, after the gap-filling precursor is supplied to the processing chamber, RF power is supplied to at least one of the upper electrode (e.g., electrode 108), the lower electrode (e.g., workpiece electrode 196), and / or the inductor antenna (e.g., inductor antenna 172). Operation 540 can be performed using any of the power schemes described with respect to operation 340. At operation 540, after the gas mixture is supplied to the processing chamber, a first RF power supply can be generated from RF power generators 120, 122 and applied to electrode 108 to generate plasma and a secondary electron beam. The secondary electron beam from electrode 108 can generate cold plasma, such as at a temperature below 100 degrees Celsius, which irradiates the surface of the substrate to form a gap-filling material thereon. Alternatively, a second optional RF power supply can be applied to the coil antenna 172 via RF power generator 174 to increase the inductively coupled power. The resulting inductively coupled power can increase the free radical flux of the substrate and increase the incident ion flux (or beam flux) of electrons in the upper chamber 100a, thereby generating a high-density beam of electrons. The inductively coupled power also reduces the sheath voltage on electrode 108, thus reducing beam energy. Additionally, a third optional RF power can be applied to the workpiece electrode 196 to optimize the ion flux and the energy incident on the substrate. This third RF power can be generated by RF power generators 146, 148 and / or an additional RF bias power generator 142.

[0101] In some embodiments using a first RF power source, the first RF power source generated from at least one of RF power generators 120, 120a, 120b, and 122 is applied to electrode 108 and controlled within a range of 1 kW to about 10 kW. It should be noted that the frequencies of the RF power generators 120, 120a, 120b, and 122 can be between 0.4 MHz and about 300 MHz. In some embodiments using a second RF power source, the second RF power source (e.g., inductively coupled power) generated from RF power generator 174 and applied to coil antenna 172 is typically controlled between about 1 kW and about 10 kW. The frequency of the inductively coupled power applied to coil antenna 172 can be between 2 MHz and about 13 MHz. In embodiments supplying power to the lower electrode, the driven frequency may include a low-frequency component, a high-frequency component, or a mixture of both. For example, RF bias power generated from RF bias power generator 142 is applied to workpiece electrode 196 and controlled within a range of 1 kW to approximately 10 kW. It should be noted that the frequency of RF bias power generator 142 can be between 0.4 MHz and approximately 300 MHz. In some embodiments, multiple frequencies are applied to workpiece electrode 196 (e.g., 2 MHz from a low-frequency RF power generator and 40 MHz from a VHF power generator).

[0102] Interstitial fillers can also be formed using process pressures, for example, between 20 mTorr and about 20 Torr. It is believed that the electron beam plasma utilized during the deposition process, along with the secondary electron beam, provides high ion bombardment, which enhances ion dissociation and the energy of the electron beam from the gas mixture, to form interstitial fillers with robust film structures.

[0103] During deposition, the substrate temperature can be controlled between room temperature (e.g., 20 degrees Celsius) and approximately 1000 degrees Celsius. The spacing between the substrate and the nozzle can be controlled between approximately 200 mils and approximately 15000 mils (e.g., approximately 200 mils to approximately 1000 mils).

[0104] As discussed elsewhere, the electron beam plasma and the secondary electron beam supplied from electrode 108 are accelerated by the electrode sheath, thus gaining additional energy upon entering the bulk plasma. These accelerated electrons provide sufficiently high energy to efficiently dissociate hydrogen from molecules, thereby generating enough hydrogen radicals to extract hydrogen impurities from carbon films (such as interstitial fillers formed on substrate 111), resulting in interstitial fillers with high purity. The accelerated secondary electron beam generates a low-temperature plasma, so-called cold plasma, above substrate 111 (at the lower chamber region 100b below grid filter 104). Low electron temperatures typically have low electron energies of less than 1 eV, such as less than 0.5 eV. Therefore, sufficient low-energy electrons from the cold plasma are generated to efficiently dissociate hydrogen molecules in vibrational states and generate hydrogen radicals, thereby increasing the hydrogen radical flux to the substrate surface.

[0105] Furthermore, when the accelerated secondary electron beam emitted from electrode 108 reaches the substrate surface, the high energy carried by the accelerated secondary electron beam (e.g., on the order of hundreds to thousands of electron volts (eV)) can induce surface reactions, such as exciting carbon sp3 surface states to form interstitial fillers on substrate 111, and disrupting weak (or inappropriate) carbon sp or sp2 bonds or even CH bonds, thus increasing sp3 bonding. This can promote the formation of diamond-like carbon materials, rather than amorphous or other structures of carbon structures. The carbon elements bonded in the interstitial fillers can be mainly formed as sp3 carbon, where four single bonds point to the corners of the tetrahedrons bonded to other carbon elements. Inappropriate sp2 hybridized carbon with two single bonds and one double bond (e.g., three bonds pointing to the corners of a triangle) often results in an amorphous film structure instead of the desired diamond-like structure. The amount of hydrogen terminating bonds in sp3-hybridized or sp2-hybridized carbon, and the degree of any missing or dangling carbon bonds, affect how tightly these carbon atoms are complexed and filled, thus determining the film density and stress. When all carbon atoms are fully interconnected, the interstitial filler is configured to form a fully sp3-hybridized structure with zero hydrogen content. In one example, the accelerated secondary electron beam can have a beam energy greater than 100 eV.

[0106] At operation 550, after performing a deposition process by adjusting the process parameters at operation 540, a gap filler is then formed in the substrate features.

[0107] Optionally, after operation 550 is completed, an optional chamber purge process can be performed to remove any residual gas and byproducts resulting from the gap filler formation process from the chamber. During the chamber purge process, a purge gas (e.g., an inert gas such as argon or nitrogen) can be supplied to the processing chamber 100 from at least one of the electrode 108, the upper gas injector 130, and the lower gas injector 134. In some embodiments, the flow of the gap filler precursor used during operation 540 is stopped, while the inert gas used during operation 540 continues to flow and act as the purge gas. A valve system can be used to control the pressure within the processing chamber 100, which controls the rate at which exhaust gas is extracted from the chamber.

[0108] In some embodiments, after operation 550 is completed, an oxygen plasma cleaning process, similar to the previously described oxygen plasma cleaning process, is performed between the CVD and PVD processes to remove any film deposited on the surface of the upper electrode during the CVD process. Thus, the carbon surface of electrode 108 is cleaned before the PVD process begins.

[0109] Similar to operation 330, at operation 570, the pressure in the processing chamber is stabilized for a predefined RF turn-on delay period. Any suitable fixed time delay can be used to achieve the desired conditions. The process of operation 530 can be performed simultaneously with, sequentially with, or partially overlap with the processes of operations 520 and 540. In some embodiments, the pressure is stabilized to a pressure from about 0.1 mTorr to about 5 Torr.

[0110] The predefined RF turn-on delay period is a fixed time delay, defined as the time period between performing the CVD process and impacting or generating plasma at operation 580. Any suitable fixed time delay can be used to achieve the desired pressure conditions. The length of the RF turn-on delay period is typically chosen such that the pressure within the processing chamber is stabilized to the pressure required for the physicochemical vapor deposition process. The process at operation 570 can be performed simultaneously with, sequentially with, or partially overlapped with the processes at operations 560 and 580. In some embodiments, the pressure is stabilized to a range from about 0.1 mTorr to about 50 mTorr (e.g., between about 1 mTorr and about 10 mTorr). Typically, PVD process pressures are extremely low to maximize ion energy.

[0111] After the desired CVD deposition time, at operation 580, RF power is applied to the upper electrode (e.g., electrode 108) while inert gas flows into the processing chamber. The inert gas may be the same inert gas used during the CVD deposition process, or it may be a different inert gas. In some embodiments, the gap-filling precursor used during the CVD process is stopped while inert gas continues to flow into the chamber. RF power is applied to at least the upper electrode during the PVD process. The upper electrode can be powered by multiple RF frequency sources to maximize sputtering yield. In some embodiments, RF power may also be applied to the lower electrode (e.g., workpiece electrode 196) during the PVD process. The lower electrode may be powered to introduce moderate ion bombardment to densify the film and crosslink the PVD layer to the CVD layer. In some embodiments, a magnetic field can be used to further enhance the plasma density at low pressure, thereby increasing the carbon sputtering rate. For example, a magnetic field can be applied by magnets 160-1 and 160-2. The magnetic field may have a strength of less than or equal to 1000 gauss (e.g., from about 20 gauss to about 700 gauss; or from about 100 gauss to about 500 gauss).

[0112] In some embodiments, during the PVD process at operation 580, power is supplied only to the upper electrode (e.g., electrode 108). For example, a first RF power source generated from at least one of RF power generators 120, 120a, 120b, and 122 is applied to electrode 108 and controlled within a range of 1 kW to about 10 kW. It should be noted that the frequencies of the RF power generators 120, 120a, 120b, and 122 may be between 0.4 MHz and about 300 MHz. In this example, power is applied only to the upper electrode (e.g., not to the lower electrode (e.g., workpiece electrode 196) or the inductor antenna (e.g., inductor antenna 172)). In some embodiments, the frequency applied to the upper electrode is between 0.4 MHz and about 300 MHz. In some embodiments, a high frequency (e.g., between about 11 MHz and 60 MHz) is applied to the upper electrode. In some embodiments, a low frequency (e.g., between about 0.4 kHz and 10 MHz) is applied to the upper electrode. In some embodiments, multiple frequencies are applied to the upper electrode (e.g., 2 MHz from the low-frequency RF power generator 122 and 40 MHz from the VHF power generator 120a).

[0113] In another example, during operation 580, both the upper electrode (e.g., electrode 108) and the lower electrode (e.g., workpiece electrode 196) are simultaneously powered using any of the aforementioned conditions. For example, RF power generated from at least one of RF power generators 120, 120a, 120b, 122 is applied to the upper electrode and controlled within a range of 1 kW to about 10 kW, and a second RF power (biased or supplied) is applied to the lower electrode 196 and controlled within a range of about 1 kW to about 10 kW. In this example, power is applied to both electrode 108 and workpiece electrode 196 (e.g., no power is applied to the inductor antenna (e.g., inductor antenna 172)). In some embodiments, the frequency applied to electrode 108 is between about 0.4 MHz and about 300 MHz, and the frequency applied to workpiece electrode 196 is between about 0.4 MHz and about 300 MHz. In some embodiments, multiple frequencies are applied to electrode 108 and / or workpiece electrode 196 (e.g., 2 MHz from a low-frequency RF power generator and 40 MHz from a VHF power generator).

[0114] At operation 590, after performing a deposition process by adjusting the process parameters at operation 580, carbon is sputtered onto the interstitial filler in substrate 111.

[0115] The CVD process (e.g., operation at 520 to 550) and the PVD process (e.g., operation at 560 to 590) can be run repeatedly until the required amount of interstitial filler has been deposited. Furthermore, although the deposition sequence is described as CVD followed by PVD, PVD followed by CVD can also be used.

[0116] In some embodiments, PVD and CVD processes are performed simultaneously. In this embodiment, the CVD film may also be deposited on the carbon target surface on the top electrode, thereby hindering the sputtering process. In some embodiments, an inert purge gas flows in through the top electrode or is injected peripherally into the upper portion of the chamber (e.g., upper chamber 100a), and the carbon source gas is injected into the lower portion of the chamber (lower chamber 100b). This minimizes the back diffusion of the carbon source gas to the top electrode, thereby reducing carbon film deposition on the top electrode surface.

[0117] In some embodiments, the gap filler formed as described herein is configured to have a value greater than or equal to 2.0 g / cm³. 3 (For example, at approximately 2.0 g / cm³) 3 Approximately 2.5 g / cm³ 3 The density is between [a certain value]. In some embodiments, the gap filler has a stress of 500 MPa or less.

[0118] In some embodiments, the temperature of the workpiece support base 110 on which the substrate 111 is positioned can be used to control the stress of the deposited carbon film. The inventors have discovered that the temperature of the support base affects the film stress and can be used to reduce it. For example, given a specific power / pressure / gas combination, the stress of the deposited interstitial filler is approximately -800 MPa when the temperature of the support base is 60 degrees Celsius. However, when the temperature of the support base is reduced to 10 degrees Celsius, the stress of the deposited film decreases to approximately -600 MPa. Additionally, the film stress can be modulated using helium gas flowing between the workpiece support surface 110a on the support surface and the back surface of the substrate 111. In some embodiments, the helium gas is operated at a pressure between approximately 15 Torr and approximately 30 Torr, and the temperature of the support base is set in the range of approximately 20 degrees Celsius to approximately 700 degrees Celsius.

[0119] Therefore, electron beam plasma deposition provides a method for forming interstitial fillers with desired density and low stress. This method advantageously provides interstitial fillers possessing one or more desired mechanical properties, such as low stress and high density, high etch selectivity, or transparency. The improved mechanical properties of the interstitial fillers provide high film quality while maintaining a predetermined range of film flatness and stress levels.

[0120] Figure 6A A schematic diagram of a substrate processing system 732 is depicted, which can be used to perform gap filler deposition according to one or more embodiments described herein. The substrate processing system 732 includes a processing chamber 700 coupled to a gas distribution plate 730 and a controller 710. The processing chamber 700 typically includes a top wall 724, side walls 701, and a bottom wall 722 defining a processing space 726. A substrate support element 746 is disposed within the processing space 726 of the processing chamber 700. The substrate support element 746 typically includes an electrostatic chuck 750 supported by a rod 760. The electrostatic chuck 750 can typically be made of aluminum, ceramic, and other suitable materials. A displacement mechanism (not shown) can be used to move the electrostatic chuck 750 vertically within the processing chamber 700.

[0121] A vacuum pump 702 is coupled to a port formed in the bottom of the processing chamber 700. The vacuum pump 702 is used to maintain the required gas pressure in the processing chamber 700. The vacuum pump 702 also extracts processed gases and processing byproducts from the processing chamber 700.

[0122] The substrate processing system 732 may further include additional devices for controlling chamber pressure, such as valves (e.g., throttle valves and isolation valves) positioned between the processing chamber 700 and the vacuum pump 702 to control chamber pressure.

[0123] A gas distribution element 720 with multiple orifices 728 is disposed on top of the processing chamber 700, above the electrostatic chuck 750. The orifices 728 of the gas distribution element 720 are used to introduce processing gases into the processing chamber 700. The orifices 728 may have different sizes, numbers, distributions, shapes, designs, and diameters to facilitate the flow of various processing gases for different process requirements. The gas distribution element 720 is connected to a gas distribution plate 730, which allows the supply of various gases to the processing space 726 during processing. Plasma is formed by the processing gas mixture exiting the gas distribution element 720 to enhance the thermal decomposition of the processing gases, thereby resulting in material deposition on the surface 791 of the substrate 790.

[0124] Gas distribution element 720 and electrostatic chuck 750 may form a pair of spaced-apart electrodes in processing space 726. One or more RF power supplies 740 provide a bias potential to gas distribution element 720 via optional matching network 738 to facilitate plasma generation between gas distribution element 720 and electrostatic chuck 750. Alternatively, RF power supply 740 and matching network 738 may be coupled to gas distribution element 720, electrostatic chuck 750, or both gas distribution element 720 and electrostatic chuck 750, or coupled to an antenna (not shown) disposed outside processing chamber 700. In some embodiments, RF power supply 740 may generate power at frequencies of 350 kHz, 2 MHz, 13.56 MHz, 27 MHz, 40 MHz, 60 MHz, or 100 MHz. In some embodiments, RF power supply 740 may provide power between about 100 watts and about 3000 watts at frequencies between about 50 kHz and about 13.6 MHz. In some embodiments, the RF power supply 740 can provide power between about 500 watts and about 1800 watts at a frequency of about 50 kHz to about 13.6 MHz.

[0125] The controller 710 includes a central processing unit (CPU) 712, a memory 716, and support circuitry 714 for controlling the process sequence and regulating airflow from the gas distribution plate 730. The CPU 712 can be any type of general-purpose computer processor suitable for industrial environments. Frequently used software programs can be stored in the memory 716, such as random access memory, read-only memory, floppy disk or hard disk drives, or other forms of digital storage. The support circuitry 714 is conventionally coupled to the CPU 712 and may include cache, clock circuitry, input / output systems, power supplies, etc.

[0126] The controller, which may be included in any of the processing devices, may have a processor, memory coupled to the processor, input / output devices coupled to the processor, and circuitry for communication between different electronic components. The memory may include one or more of temporary memory (e.g., random access memory) and non-temporary memory (e.g., storage).

[0127] The processor's memory or computer-readable medium may be one or more readily available memories, such as random access memory (RAM), read-only memory (ROM), floppy disk, hard disk, or any other form of digital storage, whether local or remote. The memory may hold a set of instructions that can be operated by the processor to control system parameters and components. Supporting circuitry is coupled to the processor to support it in a conventional manner. For example, the circuitry may include caches, power supplies, clock circuits, input / output circuits, subsystems, etc.

[0128] The process can generally be stored in memory as a general-purpose software program, which, when executed by a processor, causes the processing chamber to perform the process of this disclosure. The general-purpose software program can also be stored and / or executed by a second processor (not shown), which is located remotely from the hardware controlled by the processor. Some or all of the methods of this disclosure can also be executed in hardware. Thus, the process can be implemented in software and executed using a computer system, implemented in hardware as, for example, an application-specific integrated circuit or other type of hardware, or implemented as a combination of software and hardware. When executed by a processor, the software routine transforms a general-purpose computer into a special-purpose computer (controller) that controls the chamber operation to enable the process to be executed.

[0129] Via a series of signal cables, uniformly referred to as signal bus 718 (in) Figure 6A (Some of these are shown in the middle figure) to handle bidirectional communication between the controller 710 and various components of the substrate processing system 732.

[0130] Figure 6B A schematic cross-sectional view is depicted of another substrate processing system 780 that can be used to practice the embodiments described herein. The substrate processing system 780 is similar to... Figure 6A The substrate processing system 732 differs from the substrate processing system 780 in that the substrate processing system 780 is configured such that the processing gas from the gas distribution plate 730 flows through the sidewall 701 across the surface 791 of the substrate 790. Additionally, electrodes 782 are used instead of... Figure 6A The gas distribution element 720 is depicted. Electrode 782 can be configured for secondary electron generation. In some embodiments, electrode 782 is a silicon-containing electrode.

[0131] Figure 7 A schematic cross-sectional view of a substrate support element 746 is shown, which can be used to practice some embodiments. Figure 6A and Figure 6B Used in the processing system. (Reference) Figure 7 The electrostatic chuck 750 may include an embedded heater element 770 adapted to control the temperature of a substrate 790 supported on an upper surface 792 of the electrostatic chuck 750. The electrostatic chuck 750 can be heated resistively by applying current from a heater power supply 706 to the heater element 770. The heater power supply 706 may be coupled via an RF filter 816. The RF filter 816 can be used to protect the heater power supply 706 from RF energy. The heater element 770 may be encapsulated in a nickel-iron-chromium alloy (e.g., INCOLOY). ® The sheath contains nickel-chromium wires. The current supplied from the heater power supply 706 is regulated by controller 710 to control the heat generated by the heater element 770, thereby maintaining the substrate 790 and the electrostatic chuck 750 at a substantially constant temperature during film deposition. The supplied current can be adjusted to selectively control the temperature of the electrostatic chuck 750 between approximately -50 degrees Celsius and approximately 600 degrees Celsius.

[0132] refer to Figure 6A and Figure 6B A temperature sensor 772 (such as a thermocouple) can be embedded in the electrostatic chuck 750 to monitor the temperature of the electrostatic chuck 750 in a conventional manner. The controller 710 uses the measured temperature to control the power supplied to the heater element 770 to maintain the substrate at the desired temperature.

[0133] The electrostatic chuck 750 includes a clamping electrode 810, which may be a mesh of conductive material. The clamping electrode 810 can be embedded in the electrostatic chuck 750. The clamping electrode 810 is coupled to a clamping power supply 812, which, when powered, electrostatically clamps the substrate 790 to the upper surface 792 of the electrostatic chuck 750.

[0134] The clamping electrode 810 can be configured as a unipolar or bipolar electrode, or have another suitable arrangement. The clamping electrode 810 can be coupled to a clamping power supply 812 via an RF filter 214, which provides direct current (DC) power to electrostatically clamp the substrate 790 to the upper surface 792 of the electrostatic chuck 750. The RF filter 214 prevents damage to electrical equipment from the RF power used to form plasma within the processing chamber 700 or prevents electrical hazards outside the chamber. The electrostatic chuck 750 can be made of a ceramic material such as AlN or Al2O3. Alternatively, the electrostatic chuck 750 can be made of a polymer such as polyimide, polyetheretherketone, or polyaryletherketone.

[0135] The power application system 220 is coupled to the substrate support element 746. The power application system 220 may include a heater power supply 706, a clamping power supply 812, a first radio frequency (RF) power supply 830, and a second RF power supply 840. Embodiments of the power application system 220 may further include a controller 710 and a sensor device 850, which communicates with both the controller 710 and the first and second RF power supplies 830 and 840.

[0136] The controller 710 can also be used to control the plasma from the process gas by applying RF power from the first RF power source 830 and the second RF power source 840, so as to deposit a material layer on the substrate 790.

[0137] As described above, the electrostatic chuck 750 includes a clamping electrode 810, which in one aspect serves to clamp the substrate 790 and also acts as a first RF electrode. The electrostatic chuck 750 may also include a second RF electrode 860, which, together with the clamping electrode 810, can apply RF power to modulate the plasma. A first RF power supply 830 may be coupled to the second RF electrode 860, while a second RF power supply 840 may be coupled to the clamping electrode 810. A first matching network and a second matching network may be provided for the first RF power supply 830 and the second RF power supply 840, respectively. As shown, the second RF electrode 860 may be a solid metal plate of conductive material. Alternatively, the second RF electrode 860 may be a grid of conductive material.

[0138] The first RF power supply 830 and the second RF power supply 840 may generate power at the same frequency or different frequencies. In some embodiments, one or both of the first RF power supply 830 and the second RF power supply 840 may independently generate power at frequencies from about 350 kHz to about 100 MHz (e.g., 350 kHz, 2 MHz, 13.56 MHz, 27 MHz, 40 MHz, 60 MHz, or 100 MHz). In some embodiments, the first RF power supply 830 may generate power at a frequency of 13.56 MHz, and the second RF power supply 840 may generate power at a frequency of 2 MHz, or vice versa. The RF power from one or both of the first RF power supply 830 and the second RF power supply 840 may be varied to adjust the plasma. For example, a sensor device 850 may be used to monitor the RF energy from one or both of the first RF power supply 830 and the second RF power supply 840. Data from sensor device 850 can be communicated to controller 710, and controller 710 can be used to change the power applied through first RF power supply 830 and second RF power supply 840.

[0139] The number / percentage of sp3 hybrid carbon atoms in diamond-like carbon materials can vary depending on the application. In some embodiments, the diamond-like carbon material may contain at least 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, or 85% sp3 hybrid carbon atoms. The diamond-like carbon material may contain up to 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, or 90% sp3 hybrid carbon atoms. The diamond-like carbon material may contain from about 50% to about 90% sp3 hybrid carbon atoms. The diamond-like carbon material may contain from about 60% to about 70% sp3 hybrid carbon atoms.

[0140] In essence, the following exemplary deposition process parameters can be used to form interstitial fillers within substrate features. The wafer temperature can range from about -50°C to about 350°C (e.g., from about 10°C to about 100°C; or from about 10°C to about 50°C). The chamber pressure can range from about 0.5 mTorr to about 10 Torr (e.g., from about 2 mTorr to about 50 mTorr; or between about 2 mTorr and about 10 mTorr). The flow rate of the interstitial filler precursor can range from about 10 sccm to about 1000 sccm (e.g., from about 100 sccm to about 200 sccm, or from about 750 sccm to about 200 sccm). The flow rate of the dilution gas can individually range from 50 sccm to about 50000 sccm (e.g., from about 100 sccm to about 500 sccm; or from about 50 sccm to about 100 sccm). The spacing between the gas distribution element and the substrate can be from about 1,000 mils to about 15,000 mils (e.g., from about 6,000 mils to about 12,000 mils, or from about 8,000 mils to about 12,000 mils).

[0141] The interstitial filler can be deposited to a thickness between approximately 5 Å and approximately 20,000 Å (e.g., between approximately 900 Å and approximately 5,000 Å; between approximately 2,000 Å and approximately 9,000 Å; or between approximately 5 Å and approximately 200 Å). The above process parameters provide examples of process parameters for a 900 mm substrate in a deposition chamber available from Applied Materials, Inc., Santa Clara, California.

[0142] The interstitial filler may have a refractive index or n value (n (at 633 nm)) greater than 2.0 (e.g., from about 2.0 to about 3.0, such as 2.3). The carbon material of diamond-like carbon may have an extinction coefficient or k value (K (at 633 nm)) greater than 0.1 (e.g., from about 0.2 to about 0.3, such as 0.25).

[0143] Carbon materials like diamond can have stresses (MPa) less than about -900 MPa, for example, from about -600 MPa to about -900 MPa, from about -600 MPa to about -500 MPa, such as about -550 MPa.

[0144] Diamond-like carbon materials can have a density greater than or equal to approximately 1.8 g / cm³. 3 The density (g / cc), for example, greater than or equal to about 2.0 g / cm³. 3 or greater than or equal to approximately 2.5 g / cm³ 3 For example, from approximately 1.8 g / cm³ 3 Approximately 2.5 g / cm³ 3 .

[0145] Diamond-like carbon materials can have an elastic modulus (GPa) greater than 750 GPa (e.g., from about 200 GPa to about 10 GPa).

[0146] Figure 8 A flowchart depicting a method 900 for forming a gap filler in a substrate feature according to one or more embodiments of this disclosure. Figures 5A to 5B This is a cross-sectional view of the substrate, showing the sequence of gap fillers formed in the substrate features according to method 900. It should be understood that... Figure 8 The operations described herein can be performed simultaneously and / or with Figure 8 The order described in the text is different from the order in which they are executed.

[0147] Method 900 begins at operation 910 with placing a substrate (such as, Figure 5A The substrate 10 depicted in the figure is positioned in the processing chamber (such as, Figure 6A or Figure 6B In the processing chamber 700 depicted herein, the substrate 10 may be... Figure 6A , Figure 6B and Figure 7 The substrate 790 depicted herein. The substrate 10 can be positioned on an electrostatic chuck (e.g., the upper surface 792 of an electrostatic chuck 750).

[0148] Figure 5A A partial cross-sectional view of a substrate 10 having feature 12 is shown. As used in this context, the term "feature" means any intentional surface irregularity. Suitable examples of features include, but are not limited to, a groove having a top, two sidewalls, and a bottom; a recess having a top and two sidewalls but no separate bottom; and a through-hole having sidewalls extending downward from a surface having an open bottom or a bottom formed of a material different from the sidewalls.

[0149] Figures 5A to 5B A substrate with a single feature is shown for illustrative purposes; however, those skilled in the art will understand that more than one feature may be present. The shape of feature 12 may be any suitable shape, including but not limited to trenches and cylindrical through-holes.

[0150] The substrate 10 has a top surface 20. The at least one feature 12 forms an opening in the top surface 20. The feature 12 extends from the top surface 20 to a bottom surface 30 at a depth D. The feature 12 has a first sidewall 14 and a second sidewall 16 defining the opening width W of the feature 12. The opening region formed by the sidewalls and the bottom is also referred to as a gap.

[0151] In a particular embodiment, feature 12 is a trench. The feature may have any suitable aspect ratio (the ratio of the feature's depth D to its width W). In some embodiments, the aspect ratio is greater than or equal to about 5:1, 10:1, 15:1, 20:1, 25:1, 30:1, 35:1, or 40:1.

[0152] The substrate 10 may be made of silicon-based material or any suitable insulating or conductive material, as needed, and has features 12 disposed on the substrate 10, which may be filled with gap filler 50, such as... Figure 5B As shown in the image.

[0153] As in Figure 5A As shown in the exemplary embodiments depicted, the substrate 10 may have a top surface 20, which is substantially flat (as shown), non-uniform, or a substantially flat surface having a structure formed thereon or additional features formed therein.

[0154] In some embodiments, the substrate 10 may be a material such as crystalline silicon (e.g., Si). <100> or Si <111> Substrate 10 can be made of various materials, including silicon oxide, strained silicon, silicon-germanium, doped or undoped polycrystalline silicon, doped or undoped silicon substrates, patterned or unpatterned silicon-on-insulator (SOI) substrates, carbon-doped silicon oxide, silicon nitride, doped silicon, germanium, gallium arsenide, glass, and sapphire. Substrate 10 can have various sizes, such as 200 mm, 900 mm, and 450 mm, or other diameters, and can be rectangular or square panels. Unless otherwise stated, the embodiments and examples described herein are performed on substrates with a diameter of 200 mm, 900 mm, or 450 mm. In embodiments where an SOI structure is used on substrate 10, substrate 10 may include an embedded dielectric layer disposed on a silicon substrate. In the embodiments depicted herein, substrate 10 may be a crystalline silicon substrate.

[0155] It should be noted that gap fillers may be formed on any surface or any portion (including top surface 20) of the substrate 10, inside or outside the feature 12 present on the substrate 10.

[0156] In one or more embodiments, the deposited gap filler 50 is substantially free of seams formed in the gaps. Seam formation occurs when the film thickness is closed on top of feature 12 before the feature is filled, creating a "bread-like" appearance. Seams can be any gaps, spacers, or pores formed between the sidewalls 14, 16 of feature 12.

[0157] At operation 920, a clamping voltage is applied to the electrostatic chuck to clamp the substrate 10 to the electrostatic chuck. In some embodiments, when the substrate 10 is positioned on the upper surface of the electrostatic chuck 750, the upper surface 792 provides support and clamps the substrate 10 during processing. The electrostatic chuck 750 flattens the substrate 10 to fit snugly against the upper surface 792 to prevent backside deposition. An electrical bias voltage is provided to the substrate 10 via a clamping electrode 810. The clamping electrode 810 is electronically communicative to a clamping power supply 812, which supplies a bias voltage to the clamping electrode 810. In some embodiments, the clamping voltage is between about 10 volts and about 9000 volts. In some embodiments, the clamping voltage is between about 100 volts and about 2000 volts. In some embodiments, the clamping voltage is between about 200 volts and about 1000 volts.

[0158] During operation 920, several process parameters can be adjusted. In some embodiments suitable for processing 900mm substrates, the process pressure in the processing space can be maintained at about 0.1 mTorr to about 10 Torr (e.g., about 2 mTorr to about 50 mTorr; or about 5 mTorr to about 20 mTorr). In some embodiments suitable for processing 900mm substrates, the processing temperature and / or substrate temperature can be maintained at about -50°C to about 350°C (e.g., about 0°C to about 50°C; or from about 10°C to about 20°C).

[0159] In some embodiments, a constant clamping voltage is applied to the substrate 10. In some embodiments, the clamping voltage can be pulsed to the electrostatic chuck 750. In some embodiments, a back-side gas can be applied to the substrate 10 while the clamping voltage is applied to control the temperature of the substrate. The back-side gas may include, but is not limited to, helium (He), argon (Ar), etc.

[0160] At operation 930, plasma is generated at the substrate level by applying a first RF bias voltage to the electrostatic chuck. The plasma generated at the substrate level can be generated in a plasma region between the substrate and the electrostatic chuck. The first RF bias voltage can be from about 10 watts to about 9000 watts at a frequency from about 350 kHz to about 100 MHz (e.g., 350 kHz, 2 MHz, 13.56 MHz, 27 MHz, 40 MHz, 60 MHz, or 100 MHz). In some embodiments, the first RF bias voltage is provided at a frequency of about 13.56 MHz with a power between about 250 watts and about 9000 watts. In some embodiments, the first RF bias voltage is provided to the electrostatic chuck 750 via a second RF electrode 860. The second RF electrode 860 can be electronically communicated with a first RF power supply 830, which supplies a bias voltage to the second RF electrode 860. In some embodiments, the bias power is between about 10 watts and about 9000 watts. In some embodiments, the bias power is between about 2000 watts and about 9000 watts. In some embodiments, the bias power is between about 8500 watts and about 9000 watts. The first RF power supply 830 can generate power at frequencies from about 350 kHz to about 100 MHz (e.g., 350 kHz, 2 MHz, 13.56 MHz, 27 MHz, 40 MHz, 60 MHz, or 100 MHz).

[0161] In some embodiments, operation 930 further includes applying a second RF bias to the electrostatic chuck. The second RF bias may range from about 10 watts to about 9000 watts at frequencies from about 350 kHz to about 100 MHz (e.g., 350 kHz, 2 MHz, 13.56 MHz, 27 MHz, 40 MHz, 60 MHz, or 100 MHz). In some embodiments, the second RF bias is provided at a frequency of about 2 MHz with a power between about 800 watts and about 7200 watts. In some embodiments, the second RF bias is provided to the substrate 10 via a clamping electrode 810. The clamping electrode 810 may be electronically communicated with a second RF power supply 840, which supplies a bias voltage to the clamping electrode 810. In some embodiments, the bias power is between about 10 watts and about 9000 watts. In some embodiments, the bias power is between about 500 watts and about 7500 watts. In some embodiments, the bias power is between about 800 watts and about 7200 watts. The second RF power supply 840 can generate power at frequencies from about 350 kHz to about 100 MHz (e.g., 350 kHz, 2 MHz, 13.56 MHz, 27 MHz, 40 MHz, 60 MHz, or 100 MHz). In some embodiments, the clamping voltage supplied in operation 920 is maintained during operation 930.

[0162] In some embodiments, during operation 930, a first RF bias is provided to the substrate 10 via a clamping electrode 810, and a second RF bias is provided to the substrate 10 via a second RF electrode 860. In some embodiments, the first RF bias is approximately 8500 watts (13.56 MHz), and the second RF bias is approximately 1000 watts (2 MHz).

[0163] During operation 940, a gap-filling precursor is introduced into processing space 726 to form a gap filler in the substrate features. The gap-filling precursor may flow into processing space 726 from gas distribution plate 730 via gas distribution element 720 or via sidewall 701. In some embodiments, the gap-filling precursor may further comprise an inert gas, diluent gas, nitrogen-containing gas, etchant gas, or a combination thereof. In some embodiments, the gap-filling precursor may comprise a hydrocarbon. In some embodiments, the gap-filling precursor may comprise a silicon-containing material. The gap-filling precursor may be any liquid or gas, but a preferred precursor will be a vapor at room temperature to simplify the hardware required for material metering, control, and delivery to the chamber. In some embodiments, the clamping voltage supplied during operation 920 is maintained during operation 940. In some embodiments, the process conditions established during operation 920 and the plasma formed during operation 930 are maintained during operation 940.

[0164] In some embodiments, the hydrocarbon is in a gaseous state. In some embodiments, the hydrocarbon has the general formula C0. x H y Where x has a range between 1 and 20, and y has a range between 1 and 26. For example, suitable hydrocarbons include C2H2, C3H6, CH4, C4H8, 1,3-dimethyladamantane, bicyclo[2.2.1]hept-2,5-diene (2,5-norbornene), adamantane (C... 10 H 16 norbornene (C7H) 10 (or combinations thereof). In one example, C2H2 is preferred due to the formation of a more stable intermediate (which allows for greater surface mobility).

[0165] In some embodiments, the hydrocarbon compound is an alkane (e.g., C42-C5 ... n H n+2 (where n is between 1 and 20). For example, suitable hydrocarbons include alkanes, such as methane (CH4), ethane (C2H6), propane (C3H8), and butane (C4H4). 10 ); and its isomers isobutane and pentane (C5H 12 ), hexane (C6H) 14); and its isomers 2-methylpentane, 3-methylpentane, 2,3-dimethylbutane and 2,2-dimethylbutane; or combinations thereof.

[0166] In some embodiments, the hydrocarbon is an alkane (e.g., C42-C5 ... n H 2n (where n is between 1 and 20). For example, suitable hydrocarbons include alkenes, such as acetylene, ethylene, propylene, butene and its isomers, pentene and its isomers, dienes, such as butadiene, isoprene, pentadiene, hexadiene, or combinations thereof. Additional suitable hydrocarbons include, for example, halogenated alkenes, such as monofluoroethylene, difluoroethylene, trifluoroethylene, tetrafluoroethylene, monochloroethylene, dichloroethylene, trichloroethylene, tetrachloroethylene, or combinations thereof.

[0167] In some embodiments, the hydrocarbon compound is an alkyne (e.g., C). n H 2n-2 (where n is between 1 and 20). For example, suitable hydrocarbons include alkynes, such as acetylene (C2H4), propyne (C3H4), butene (C4H8), vinylacetylene, or combinations thereof.

[0168] In some embodiments, the hydrocarbon compound is an aromatic compound, such as benzene, styrene, toluene, xylene, ethylbenzene, acetophenone, methyl benzoate, phenyl acetate, phenol, cresol, furan, α-terpinene, umbelliferene, 1,1,3,3-tetramethylbutyronitrile, t-butyl ether, t-butylethylene, methyl methacrylate, and tert-butylfurfuryl ether; compounds having the chemical formulas C3H2 and C5H4; halogenated aromatic compounds, including monofluorobenzene, difluorobenzene, tetrafluorobenzene, hexafluorobenzene, or combinations thereof.

[0169] In some embodiments, the interstitial filling precursor comprises a silicon-containing material. Suitable silicon-containing materials include substances similar to the hydrocarbon materials provided above (wherein silicon replaces carbon). For example, in some embodiments, the silicon-containing material is selected from silanes, higher silanes, cyclosilanes, halosilanes, and combinations thereof.

[0170] In some embodiments, the interstitial filling precursor further comprises one or more diluent gases. When necessary, a suitable diluent gas, such as helium (He), argon (Ar), xenon (Xe), hydrogen (H2), nitrogen (N2), or combinations thereof (among others), may be added to the gas mixture. Ar, He, and N2 may be used to control the density and deposition rate of the interstitial filling. In some embodiments, the addition of N2 and / or NH3 may be used to control the hydrogen ratio of the interstitial filling, as discussed below. Alternatively, diluent gases may not be used during deposition.

[0171] In some embodiments, the gap-filling precursor further comprises one or more nitrogen-containing gases. For example, suitable nitrogen-containing gases include pyridine, aliphatic amines, amines, nitriles, ammonia, and similar compounds.

[0172] In some embodiments, the interstitial filling precursor further comprises an inert gas. In some embodiments, an inert gas such as argon (Ar) and / or helium (He) may be supplied to the processing space 726 along with the interstitial filling precursor. Other inert gases such as nitrogen (N2) and nitric oxide (NO) may also be used to control the density and deposition rate of the interstitial filling. Additionally, a variety of other processing gases may be added to the interstitial filling precursor to modify the properties of the interstitial filling. In some embodiments, the other processing gases may be reactive gases, such as hydrogen (H2), ammonia (NH3), a mixture of hydrogen (H2) and nitrogen (N2), or combinations thereof. The addition of H2 and / or NH3 may be used to control the hydrogen ratio (e.g., the carbon to hydrogen ratio) of the deposited interstitial filling. The hydrogen ratio present in the carbon material of diamond-like carbon provides control over layer properties (such as reflectivity).

[0173] In some embodiments, the interstitial filling precursor further comprises an etchant gas. Suitable etchant gases include chlorine (Cl2), carbon tetrafluoride (CF4), nitrogen trifluoride (NF3), or combinations thereof. Without being bound by theory, it is believed that the etchant gas selectively etches sp2 hybrid carbon atoms from the film, thereby increasing the proportion of sp3 hybrid carbon atoms in the film.

[0174] In some embodiments, after the interstitial filler 412 is formed on the substrate during operation 940, the interstitial filler 412 is exposed to hydrogen radicals. In some embodiments, the interstitial filler is exposed to hydrogen radicals during the deposition process of operation 940. In some embodiments, the hydrogen radicals are formed in the RPS and transported to the processing area. Without being bound by theory, it is believed that exposing the interstitial filler to hydrogen radicals leads to selective etching of sp2 hybrid carbon atoms, thereby increasing the proportion of sp3 hybrid carbon atoms in the film.

[0175] At operation 950, after gap filler 412 has been formed on the substrate, the substrate is released from clamping. During operation 950, the clamping voltage is turned off. The reactive gas is shut off and optionally purged from the processing chamber. In some embodiments, during operation 950, the RF power is reduced (e.g., about 200W). Optionally, controller 710 monitors impedance changes to determine whether electrostatic charge has dissipated to ground via the RF path. Once the substrate has been clamped from the electrostatic chuck, the remaining gas is purged from the processing chamber. The processing chamber is evacuated, and the substrate is moved upward on the lifting rod and transferred out of the chamber.

[0176] In general, some benefits of this disclosure provide a process for depositing interstitial fillers in substrate features. In some embodiments described herein, low process pressure (millitort vs. Torr) and bottom-driven plasma enable the fabrication of interstitial fillers having approximately 60% or more of hybrid sp3 atoms. Furthermore, performing some embodiments described herein at low substrate temperatures allows for the deposition of other dielectric films at temperatures far below those currently possible with process technology, opening up applications with low thermal budgets that are currently unattainable with CVD.

[0177] When describing elements or exemplary aspects or embodiments thereof in this disclosure, the articles “a / an,” “described,” and “described” are intended to mean the presence of one or more of the elements.

[0178] The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that additional elements may exist in addition to the listed elements.

[0179] While the foregoing describes embodiments of this disclosure, other and additional embodiments of this disclosure may be devised without departing from the basic scope of this disclosure, the scope of which is defined by the appended claims.

[0180] Throughout this specification, references to "one embodiment," "some embodiments," "one or more embodiments," or "embodiment" mean that a particular feature, structure, material, or characteristic described in connection with that embodiment is included in at least one embodiment of this disclosure. Therefore, terms such as "in one or more embodiments," "in some embodiments," "in one embodiment," or "in an embodiment" appearing throughout this specification do not necessarily refer to the same embodiment of this disclosure. Furthermore, particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments.

[0181] Although the invention described herein has been illustrated with reference to specific embodiments, it should be understood that these embodiments are merely illustrative of the principles and applications of the invention. Those skilled in the art will appreciate that various modifications and variations can be made to the methods and apparatus of the invention without departing from the spirit and scope thereof. Therefore, the invention is contemplated to include modifications and variations within the scope of the appended claims and their equivalents.

Claims

1. A method for depositing interstitial filler, comprising: The substrate is positioned on an electrostatic chuck within the processing space of the processing chamber. The substrate has a substrate surface including at least one feature, the at least one feature extending to a depth from the substrate surface to a bottom surface, and the at least one feature having an opening width defined by a first sidewall and a second sidewall at the substrate surface. The gap-filling precursor is allowed to flow into the processing space from gas distribution elements spaced apart above the substrate, and the processing space is maintained at a pressure between about 0.5 mTorr and about 10 Torr. as well as Plasma is generated in the processing space above the substrate by applying a first RF bias to the electrostatic chuck to deposit a gap filler that substantially does not contain pores within at least one feature of the substrate.

2. The method of claim 1, wherein the interstitial filling precursor comprises a hydrocarbon, and the interstitial filling comprises a diamond-like carbon material.

3. The method of claim 2, wherein the diamond-like carbon material has a density greater than 1.8 g / cm³. 3 The density.

4. The method of claim 2, wherein the diamond-like carbon material has a stress in the range of about -600 MPa to about -300 MPa.

5. The method of claim 2, wherein the hydrocarbon is selected from C2H2, C3H6, CH4, C4H8, 1,3-dimethyladamantane, bicyclo[2.2.1]hept-2,5-diene (2,5-norbornene), adamantane (C 10 H 16 norbornene (C7H) 10 ) and groups consisting of their combinations.

6. The method of claim 1, wherein the gap-filling precursor comprises a silicon-containing material, and the gap-filling material comprises a dielectric material.

7. The method of claim 6, wherein the dielectric material comprises one or more of silicon, silicon oxide, or silicon nitride.

8. The method of claim 1, wherein the first RF bias is provided at a frequency from about 350 kHz to about 100 MHz with a power between about 10 watts and about 3000 watts.

9. The method of claim 1, wherein generating plasma in the processing space further comprises: A second RF bias is applied to the electrostatic chuck.

10. The method of claim 9, wherein the second RF bias is provided at a frequency from about 350 kHz to about 100 MHz with a power between about 10 watts and about 3000 watts.

11. The method of claim 1, wherein the substrate is maintained at a temperature from about 10°C to about 100°C.

12. The method of claim 1, wherein the gap-filling precursor comprises a dilution gas, the dilution gas comprising one or more of He, Ar, Xe, N2, H2, or a combination thereof.

13. The method of claim 1, wherein the at least one feature has a ratio of the depth to the opening width greater than or equal to about 10:

1.

14. The method of claim 1, wherein the spacing between the gas distribution element and the substrate is maintained between 1,000 mils and 15,000 mils.

15. A method for depositing interstitial filler, comprising: A substrate is positioned above a first electrode within the processing space of a processing chamber. The substrate has a substrate surface including at least one feature extending to a depth from the substrate surface to a bottom surface. The at least one feature has an opening width defined by a first sidewall and a second sidewall at the substrate surface. The processing chamber further includes a second electrode positioned above the first electrode and the substrate. The second electrode has a surface including a secondary electron emission material, which includes one or more of silicon-containing or carbon-containing materials. The gap-filling precursor flows into the processing space; A first RF power is applied to at least one of the first electrode and the second electrode; as well as A gap filler is formed within at least one feature of the substrate, the gap filler substantially excluding pores.

16. The method of claim 15, wherein the interstitial filling precursor comprises a hydrocarbon selected from C2H2, C3H6, CH4, C4H8, 1,3-dimethyladamantane, bicyclo[2.2.1]hept-2,5-diene (2,5-norbornene), adamantane (C 10 H 16 norbornene (C7H) 10 The group consists of the group of diamond-like carbon materials and combinations thereof.

17. The method of claim 16, wherein the diamond-like carbon material has a density greater than 1.5 g / cm³. 3 The density and stress in the range of approximately -600 MPa to approximately 100 MPa.

18. The method of claim 15, wherein the gap-filling precursor comprises a silicon-containing material, and the gap-filling material comprises a dielectric material, the dielectric material comprising one or more of silicon, silicon oxide, or silicon nitride.

19. The method of claim 15, wherein the at least one feature has a ratio of the depth to the opening width greater than or equal to about 10:

1.

20. A diamond-like carbon interstitial filler within a feature of a substrate, said interstitial filler having a density of about 1.8 g / cm³. 3 Approximately 2.5 g / cm³ 3 The density is within the range of about 50% to about 90% of sp3 hybridized carbon atoms, and the stress is less than 100 MPa. The feature extends to a depth from the surface of the substrate to the bottom surface. The feature has an opening width defined by a first sidewall and a second sidewall at the surface. The feature has a depth to opening width ratio greater than or equal to about 10:1.

Images