Method and apparatus for curing dielectric materials

Abstract

Methods and apparatuses for forming integrated circuit structures include: delivering a process gas to a process volume of a process chamber; applying low frequency RF power to an electrode disposed in the process volume formed of a high secondary electron emission coefficient material; generating a plasma comprising ions in the process volume; bombarding the electrode with the ions to cause the electrode to emit electrons and form an electron beam; and contacting a dielectric material with the electron beam to solidify the dielectric material, wherein the dielectric material is a flowable chemical vapor deposition product. In embodiments, the solidification stabilizes the dielectric material by reducing an oxygen content of the dielectric material and increasing a nitrogen content of the dielectric material.

Description

[0001] field

[0002] Embodiments of this disclosure generally relate to methods and apparatus for curing substrates and forming interconnects. More specifically, embodiments described herein relate to methods and apparatus for electron beam reactive plasma curing of dielectric materials.

[0003] background

[0004] Reliably manufacturing sub-half-micron and smaller features is one of the key technological challenges for next-generation semiconductor devices such as Very Large Scale Integration (VLSI) and Ultra Large Scale Integration (ULSI). However, as circuit technology continues to push its limits, the ever-shrinking dimensions of VLSI and ULSI interconnect technologies place even greater demands on processing power. Reliably forming gate structures on the substrate is crucial for the success of VLSI and ULSI and for ongoing efforts to continuously improve circuit density and the quality of individual substrates and dies.

[0005] To enable the fabrication of next-generation devices and structures, three-dimensional (3D) stacking of semiconductor chips is often used to improve transistor performance. By arranging transistors in three dimensions instead of the conventional two-dimensional dimensions, multiple transistors can be placed very close to each other in an integrated circuit (IC). 3D stacking of semiconductor chips shortens wire lengths and maintains low wiring delays. As the width of features such as trenches continues to shrink, the aspect ratio (depth divided by width) of semiconductor chip stacks continues to increase. One challenge in fabricating high aspect ratio features such as trenches is avoiding the formation of voids during dielectric material deposition within the trenches.

[0006] To fill the trench, a dielectric material layer, such as silicon oxide, is deposited. The dielectric layer typically covers the field as well as the walls and bottom of the feature (e.g., the trench). If the feature is wide and shallow, completely filling the feature is not difficult. However, as the feature aspect ratio increases, the trench opening will "pinch off," increasing the likelihood of voids or defects forming within the feature.

[0007] To reduce the likelihood of voids or defects forming within features (e.g., seams within trenches), numerous different process techniques have been developed to fill features with dielectric materials with minimal defects. Poor process control during deposition can lead to irregular structural profiles or premature closure of features (such as trenches), resulting in voids or air gaps within the trenches when they are filled with dielectric materials.

[0008] Flowable chemical vapor deposition (FCVD) is a method for filling features (such as trenches) from the bottom up, avoiding the formation of voids or defects. However, dielectric materials formed by FCVD methods can be unstable and may contain reactive substances that react with air, problematically forming material layers with high oxygen content (e.g., high oxygen-to-nitrogen ratios). Annealing films formed by FCVD methods is still insufficient and may not improve the overall stability and quality of the resulting dielectric film material, leading to increased device resistance.

[0009] Therefore, the inventors have provided improved curing equipment and methods suitable for improving materials formed by the FCVD method.

[0010] Overview

[0011] This document provides methods and apparatus for curing substrates and / or forming interconnect devices. In some embodiments, the method for forming an integrated circuit structure includes the steps of: delivering process gas to a process space of a process chamber; applying RF power to electrodes disposed in the process space formed of a material with a high secondary electron emission coefficient; generating an ion-containing plasma in the process space; bombarding the electrodes with ions to induce electron emission from the electrodes and form an electron beam; and contacting a dielectric material with the electron beam to cure the dielectric material, wherein the dielectric material is a flowable chemical vapor deposition product.

[0012] In some embodiments, the integrated system includes: a vacuum substrate transport chamber; a deposition chamber configured for flowable chemical vapor deposition, the deposition chamber being coupled to the vacuum substrate transport chamber; and a curing chamber coupled to the vacuum substrate transport chamber, wherein the curing chamber is configured to cure a dielectric material using an electron beam radiation source.

[0013] In some embodiments, a computer-readable medium storing instructions that, when executed, cause a process chamber to perform a method for forming an integrated circuit structure, the method comprising the steps of: delivering a process gas to a process space of the process chamber; applying RF power to electrodes disposed in the process space formed of a material with a high secondary electron emission coefficient; generating an ion-containing plasma in the process space; bombarding the electrodes with ions, causing the electrodes to emit electrons and forming an electron beam; and contacting a dielectric material with the electron beam to solidify the dielectric material, wherein the dielectric material is a flowable chemical vapor deposition product.

[0014] Other and further implementations of this disclosure are described below.

[0015] Brief description of the attached figures

[0016] The embodiments of this disclosure, which have been briefly summarized above and are discussed in more detail below, can be understood by referring to the illustrative embodiments depicted in the accompanying drawings. However, the drawings only show typical embodiments of this disclosure and should not be considered as limiting the scope, as other equivalent embodiments are permissible.

[0017] Figure 1 This disclosure describes apparatus suitable for performing deposition processes according to some embodiments thereof.

[0018] Figure 2 This disclosure describes some embodiments of devices suitable for curing dielectric layers.

[0019] Figure 3 Describing some implementations different from those described in this disclosure Figure 2 It is suitable for devices with solidified dielectric layers, but not for devices with solidified dielectric layers.

[0020] Figure 4 Describing some embodiments according to this disclosure, including Figure 1 equipment and Figure 2 or Figure 3 A top-down plan view of the equipment's processing tools.

[0021] Figure 5 This is a process flow diagram illustrating a method for forming a dielectric material according to some embodiments of the present disclosure.

[0022] Figure 6 This is a process flow diagram illustrating a method for curing dielectric materials according to some embodiments of the present disclosure.

[0023] Figures 7A-7B A cross-sectional view depicting a structure formed according to some embodiments of the present disclosure.

[0024] For ease of understanding, the same reference numerals are used where possible to denote common elements in the figures. The figures are not drawn to scale and may be simplified for clarity. Elements and features of one embodiment may be beneficially incorporated into other embodiments without further description.

[0025] Detailed Explanation

[0026] This document provides methods and apparatus for curing substrates and / or forming interconnect devices. In some embodiments, a method for forming an integrated circuit structure includes the step of contacting a dielectric material with an electron beam under conditions suitable for curing the dielectric material. The methods and apparatus of this disclosure advantageously stabilize or improve dielectric materials, such as dielectric materials formed or deposited by an FCVD method. In embodiments, the methods and apparatus of this disclosure form variations of the deposited dielectric material, for example, by using electron beam curing to modify the composition of the dielectric material. For example, in some embodiments, a silicon nitride layer of the dielectric material may be deposited having reactive hydrogen incorporated into the silicon nitride material. Unless cured, hydrogen may problematically react with air and moisture in the air, thereby forming a oxynitride layer of the dielectric material, such as silicon oxynitride (SiO2). x N y In some embodiments, the curing process according to this disclosure reduces the atomic oxygen percentage and increases the atomic nitrogen percentage of the dielectric material. In some embodiments, the dielectric material formed, for example by FCVD, is silicon nitride incorporating hydrogen, and the curing step according to this disclosure reduces unstable materials (e.g., SiO2). x N y (where the ratio of x to y is greater than 1) is formed.

[0027] Therefore, this disclosure includes depositing dielectric materials in features for semiconductor devices (e.g., trenches with high aspect ratios), particularly for three-dimensional (3D) stacking of semiconductor chips, to provide good gap-filling capability for dielectric materials filling trenches from a substrate. Figure 1 This is a cross-sectional view of a deposition processing chamber 100 for performing a deposition process according to the present disclosure, the deposition process being used to deposit dielectric materials for semiconductor applications. Suitable processing chambers that can be adapted and used herein, without limitation, include, for example, those available from Applied Materials, Inc. of Santa Clara, CA. or Processing chambers. Other process chambers, including those available from other manufacturers, may also be used appropriately in conjunction with the teachings provided herein.

[0028] Reference Figure 1In one embodiment, the deposition processing chamber 100 includes a processing chamber body 102 and a remote plasma source 104 coupled to the processing chamber body 102. The remote plasma source 104 can be any suitable source capable of generating free radicals. The remote plasma source 104 can be a remote plasma source such as a radio frequency (RF) or very high radio frequency (VHRF) capacitively coupled plasma (CCP) source, an inductively coupled plasma (ICP) source, a microwave induced (MW) plasma source, an electron cyclotron resonance (ECR) chamber, or a high-density plasma (HDP) chamber. The remote plasma source 104 may include one or more gas sources 106, and the remote plasma source 104 can be coupled to the deposition processing chamber 100 via a free radical conduit 108. One or more process gases (which may be free radical-forming gases) may enter the remote plasma source 104 via one or more gas sources 106. In one embodiment, the one or more process gases may include chlorine-containing gases, fluorine-containing gases, inert gases, oxygen-containing gases, nitrogen-containing gases, hydrogen-containing gases, or any combination thereof. The free radicals generated in the remote plasma source 104 travel through the free radical conduit 108 coupled to the deposition processing chamber 100 into the deposition processing chamber 100, and reach the internal processing area 151 defined in the deposition processing chamber 100.

[0029] The radical conduit 108 is part of the cap assembly 112, which also includes a radical cavity 110, a top plate 114, a lid rim 116, and a nozzle 118. The radical conduit 108 may comprise a material that is generally non-reactive to radicals. For example, the radical conduit 108 may comprise aluminum nitride (AlN), silicon dioxide (SiO2), yttrium oxide (Y2O3), magnesium oxide (MgO), anodized aluminum oxide (Al2O3), oxide minerals such as sapphire, ceramics comprising one or more of the following: aluminum oxide (Al2O3), oxide minerals such as sapphire, aluminum nitride (AlN), yttrium oxide (Y2O3), magnesium oxide (MgO); or plastics. A typical example of a suitable silicon dioxide (SiO2) material is quartz. The radical conduit 108 may be disposed within and supported by a radical conduit support member 120. The free radical pipe support member 120 can be set on the top plate 114, which rests on the cover edge 116.

[0030] In one embodiment, a radical cavity 110 is located below and coupled to a radical conduit 108, and radicals generated in the remote plasma source 104 travel through the radical conduit 108 to the radical cavity 110. In another embodiment, the radical cavity 110 includes a top plate 114, a cover 116, and a nozzle 118. Optionally, the radical cavity 110 may include a liner 122. The liner 122 may cover the surfaces of the top plate 114 and the cover 116 exposed to the radical cavity 110. Radicals from the remote plasma source 104 pass through a plurality of tubes 124 disposed in the nozzle 118 to enter an internal processing region 151. The nozzle 118 also includes a plurality of openings 126 with a diameter smaller than that of the plurality of tubes 124. The plurality of openings 126 are connected to an internal space (not shown) that is not in fluid communication with the plurality of tubes 124. One or more fluid sources 119 may be coupled to nozzle 118 for introducing a fluid mixture into the internal processing region 151 of the deposition processing chamber 100. The fluid mixture may include a precursor, a porogen, and / or a carrier fluid. The fluid mixture may be a mixture of gas and liquid.

[0031] The deposition chamber 100 may include a cover assembly 112, a chamber body 130, and a substrate support assembly 132. The substrate support assembly 132 may be at least partially disposed within the chamber body 130. The chamber body 130 may include a slit valve 135 to provide access to the interior of the deposition chamber 100. The chamber body 130 may include a liner 134 covering an inner surface of the chamber body 130. The liner 134 may include one or more slits 136 formed therein and a pumping passage 138 in fluid communication with a vacuum system 140. The slits 136 provide a flow path for gas to enter the pumping passage 138, which provides an outlet for gas within the deposition chamber 100.

[0032] Vacuum system 140 may include vacuum port 142, valve 144, and vacuum pump 146. Vacuum pump 146 is in fluid communication with pumping channel 138 via vacuum port 142. Slit 136 allows pumping channel 138 to be in fluid communication with internal processing region 151 within chamber body 130. Internal processing region 151 includes lower surface 148 of nozzle 118 and upper surface 150 of substrate support assembly 132, and internal processing region 151 is surrounded by liner 134.

[0033] The substrate support assembly 132 may include a substrate support member 152 to support a substrate (not shown) for processing within the chamber body 130. The substrate may be any standard wafer size, such as 300 mm. Alternatively, the substrate may be larger than 300 mm, such as 450 mm or larger. The substrate support member 152 may include aluminum nitride (AlN) or aluminum, depending on the operating temperature. The substrate support member 152 may be configured to clamp the substrate to the substrate support member 152.

[0034] The substrate support 152 can be coupled to the lifting mechanism 154 via a shaft 156 extending through a central opening 158 formed in the bottom surface of the chamber body 130. The lifting mechanism 154 can be flexibly sealed to the chamber body 130 via a bellows 160 to prevent vacuum leakage around the shaft 156. The lifting mechanism 154 allows the substrate support 152 to move vertically within the chamber body 130 between a process position and a lower transfer position. The transfer position is slightly below the opening of the slit valve 135. During operation, the spacing between the substrate 301 and the nozzle 118 can be minimized to maximize the free radical flux at the substrate surface. For example, the spacing can be between approximately 100 mm and approximately 5,000 mm. The lifting mechanism 154 can be able to rotate the shaft 156, which in turn rotates the substrate support 152, thereby causing the substrate disposed on the substrate support 152 to rotate during operation.

[0035] One or more heating elements 162 and cooling channels 164 may be embedded in the substrate support member 152. The heating elements 162 and cooling channels 164 can be used to control the temperature of the substrate during operation. The heating element 162 can be any suitable heating element, such as one or more resistance heating elements. The heating element 162 may be connected to one or more power sources (not shown). The heating element 162 can be individually controlled to have independent heating and / or cooling control for multi-zone heating or cooling. The ability to independently control multi-zone heating and cooling can improve the substrate temperature profile under any given process conditions. Coolant can flow through the cooling channels 164 to cool the substrate. The substrate support member 152 may also include a gas passage extending to the upper surface 150 to allow cooling gas to flow to the back side of the substrate.

[0036] RF source power 143 can be coupled to nozzle 118 via RF source power matching box 147. RF source power 143 can be low-frequency, high-frequency, or very high-frequency. In some embodiments, RF source power 143 is a high-frequency RF generator that can generate high-density plasma for depositing high-density films. In one example, RF source power 143 can be used as an inductively coupled RF energy transfer device that can generate and control inductively coupled plasma (ICP) generated in the internal processing region 151 above the substrate support member 152. Dynamic impedance matching from RF source power matching box 147 can be provided when inductively coupled plasma (ICP) is generated.

[0037] In addition to the RF source power 143, the RF bias power source 145 can also be coupled to the substrate support member 152. The substrate support member 152 is configured as a cathode and includes an electrode 163 coupled to the RF bias power source 145. The RF bias power source 145 is coupled between the electrode 163 disposed in the substrate support member 152 and another electrode (e.g., nozzle 118 or top plate (e.g., top plate 114 of chamber body 130)). The RF bias power generated by the RF bias power source 145 excites and sustains the plasma discharge formed by the gas disposed in the internal processing region 151 of the chamber body 130.

[0038] In one operating mode, substrate 301 is disposed on substrate support member 152 within deposition processing chamber 100. Process gas and / or gas mixture is introduced into chamber body 130 from gas source 106 through nozzle 118. Vacuum pump 146 maintains pressure inside chamber body 130 while removing deposition byproducts.

[0039] Controller 170 is coupled to deposition chamber 100 to control its operation. Controller 170 includes a central processing unit (CPU) 172, memory 174, and support circuitry 176 for controlling process sequence and regulating airflow from gas source 106. CPU 172 can be any type of general-purpose computer processor suitable for use in an industrial environment. Software routines can be stored in memory 174, such as random access memory, read-only memory, floppy disk or hard disk drive, or other forms of digital storage. Support circuitry 176 is conventionally coupled to CPU 172 and may include cache, clock circuitry, input / output systems, power supplies, and the like. Bidirectional communication between controller 170 and the various components of deposition chamber 100 is handled via a network of signal cables.

[0040] The methods and apparatus of this disclosure include curing dielectric materials in features (e.g., trenches with high aspect ratios for semiconductor devices), particularly for stabilizing or altering dielectric materials. Reference is now made to... Figure 2 This diagram shows a cross-sectional view of an electron beam processing chamber 200 suitable for curing dielectric materials according to the present disclosure. In one embodiment, the electron beam processing chamber 200 has a chamber body 202 that defines a process space 201. In one embodiment, the chamber body 202 has a generally cylindrical shape and may be made of a material suitable for maintaining a vacuum pressure environment therein, such as a metallic material, for example, aluminum or stainless steel.

[0041] In one embodiment, a top plate 206 is coupled to a chamber body 202 and forms a process space 201. In one embodiment, the top plate 206 is formed of a conductive material, such as the material used to manufacture the chamber body 202. The top plate 206 is coupled to and supports an electrode 208, which is located on the top plate 206. In one embodiment, the electrode 208 is coupled to the top plate 206 such that the electrode 208 is disposed adjacent to the process space 201. In one embodiment, the electrode 208 is formed of a process-compatible material having a high secondary electron emission coefficient, such as silicon, carbon, silicon carbide, or silicon oxide. Alternatively, the electrode 208 is formed of a metal oxide material, such as aluminum oxide (Al2O3), yttrium oxide (Y2O3), or zirconium oxide (ZrO2). A dielectric ring 209 formed of an electrically insulating material is coupled to the chamber body 202 and surrounds the electrode 208. As shown in the figure, the dielectric ring 209 is disposed between the chamber body 202 and the top plate 206, and the electrode 208 is supported on the dielectric ring 209.

[0042] A base 210 is disposed in a process space 201. A substrate 211 is supported on the base 210, and a substrate support surface 210a is oriented parallel to the electrode 208. In one embodiment, the base 210 is axially movable via a lifting servo 212. During operation, the substrate support surface 210a is maintained at a distance of approximately 1 inch to approximately 30 inches from the top electrode (e.g., electrode 208). In one embodiment, the base 210 includes an insulating puck 242 forming the substrate support surface 210a, an electrode 244 disposed within the insulating puck 242, and an adsorption voltage supply 248 connected to the electrode 244. Furthermore, a base layer 246 located below the insulating puck 242 has internal passages 249 for circulating a heat transfer medium (e.g., a liquid) from a circulation supply 245. In one embodiment, the circulation supply 245 serves as a heat sink. In another embodiment, the circulation supply 245 serves as a heat source. In one embodiment, the temperature of the base 210 is maintained between approximately -20°C and approximately 1000°C.

[0043] An RF power generator 220 having a VHF frequency (e.g., 160 MHz) and a lower-frequency RF power generator (e.g., RF power generator 222) having frequencies below the VHF or HF range (e.g., in the MF or LF range, such as between about 100 kHz and about 60 MHz, for example, about 2 MHz) are coupled to electrode 208 via an impedance match 224 and an RF feed conductor 223. In one embodiment, the impedance match 224 is adapted to provide impedance matching at the different frequencies of the RF power generators 220 and 222, and is filtered to isolate the power generators from each other. The output power levels of the RF power generators 220 and 222 are independently controlled by a controller 226. Power from the RF power generators 220 and 222 is coupled to electrode 208, as will be described in detail below.

[0044] In one embodiment, the top plate 206 is conductive and in electrical contact with the electrode 208. Power from the impedance matching 224 is conducted through the top plate 206 to the electrode 208. In one embodiment, the chamber body 202 is maintained at ground potential. In one embodiment, the grounded inner surface (i.e., the chamber body 202) inside the electron beam processing chamber 200 is coated with a process-compatible material, such as silicon, carbon, silicon carbide, or silicon oxide. In an alternative embodiment, the grounded inner surface inside the electron beam processing chamber 200 is coated with a material such as alumina (Al2O3), yttrium oxide (Y2O3), or zirconium oxide (ZrO2).

[0045] In one embodiment, the RF power generator 220 is replaced by two separately controlled VHF power generators 220a and 220b. VHF power generator 220a has an output frequency in the lower portion of the VHF band (e.g., 30 MHz to 150 MHz), while VHF power generator 220b has an output frequency in the higher portion of the VHF band (e.g., 150 MHz to 300 MHz). The controller 226 controls the plasma ion density by selecting a ratio between the output power levels of the VHF power generators 220a and 220b.

[0046] Using two VHF power generators 220a and 220b, the radial plasma uniformity in the process space 201 can be controlled by selecting the distance between the electrode 208 and the base 210. In some embodiments, a lower VHF frequency produces a high radial distribution of plasma ion density at the edges of the process space 201, while a higher VHF frequency produces a high radial distribution of plasma ion density at the center. With such a selection, the power levels of the two VHF power generators 220a and 220b can produce a plasma with a substantially uniform radial plasma ion density.

[0047] In one embodiment, top plate 206 serves as a support for electrode 208 and includes an insulating layer 250 containing an adsorption electrode 252 facing electrode 208. A DC adsorption voltage supply 254 is coupled to the adsorption electrode 252 via a feed conductor 255 for electrostatically clamping electrode 208 to top plate 206. A DC blocking capacitor 256 is connected in series with the output of impedance matching 224. Controller 226 controls DC adsorption voltage supply 254. In one embodiment, an RF feed conductor 223 from impedance matching 224 is connected to the electrode support or top plate 206, rather than directly to electrode 208. In such an embodiment, RF power from RF feed conductor 223 is capacitively coupled from the electrode support to electrode 208.

[0048] In one embodiment, an internal passage 278 for conducting a heat-conducting liquid or medium within the top plate 206 is connected to a heat medium circulation supply 280. The heat medium circulation supply 280 serves as a heat sink or heat source. The mechanical contact between the electrode 208 and the top plate 206 is sufficient to maintain high thermal conductivity between the electrode 208 and the top plate 206. Figure 2 In this embodiment, the force of mechanical contact is adjusted by the electrostatic clamping force provided by the DC adsorption voltage supply 254.

[0049] In one embodiment, the upper gas injector 230 supplies process gas to the process space 201 via a first valve 232. In another embodiment, the lower gas injector 234 supplies process gas to the process space 201 via a second valve 236. The upper gas injector 230 and the lower gas injector 234 are disposed in the sidewall of the chamber body 202. Gas is supplied from an array of process gas suppliers (e.g., supplier 238) via a valve array 240, which may include the first valve 232 and the second valve 236. In one embodiment, the gas species and gas flow rate delivered to the process space 201 are independently controllable. For example, the gas flow through the upper gas injector 230 may be different from the gas flow through the lower gas injector 234. A controller 226 controls the valve array 240.

[0050] In one embodiment, an inert gas (e.g., argon or helium) is supplied to the process space 201 through an upper gas injector 230, while a process gas is supplied to the process space 201 through a lower gas injector 234. In some embodiments, the inert gas supplied to the process space 201 adjacent to the electrode 208 serves to buffer the electrode 208 from the reactive plasma formed in the process space 201, thereby extending the lifespan of the electrode 208. In another embodiment, the process gas is supplied to the process space 201 through both the upper gas injector 230 and the lower gas injector 234.

[0051] In some embodiments, plasma is generated in process space 201 via various bulk and surface processes (e.g., via capacitive coupling). In one embodiment, high-energy ion bombardment of the inner surface of the top electron emission electrode (e.g., electrode 208) also promotes plasma generation. In one example, electrode 208 is biased with a generally negative charge (e.g., by applying a voltage from DC adsorption voltage supply 254). In one embodiment, the bias power applied to electrode 208 is between about 1 kHz and about 10 kHz, and the frequency is between about 400 kHz and about 200 MHz. The inventors believe that ions generated by capacitively coupled plasma are influenced by an electric field that encourages the plasma-generated ions to bombard electrode 208.

[0052] The ion bombardment energy and plasma density of electrode 208 vary with both RF power generators 220 and 222. The ion bombardment energy of electrode 208 is generally controlled by the lower frequency power from RF power generator 222, while the plasma density in process space 201 is generally controlled (enhanced) by the VHF power from RF power generator 220. In some embodiments, the ion bombardment of electrode 208 causes the electrode to emit secondary electrons. These negatively charged, high-energy secondary electrons are emitted from the inner surface of electrode 208 and are accelerated away from the electrode due to the negative bias voltage of electrode 208.

[0053] The flux of high-energy electrons from the emitting surface of electrode 208 is considered an electron beam and can be oriented substantially perpendicular to the inner surface of electrode 208. The beam energy of the electron beam is approximately equal to the ion bombardment energy of electrode 208, which is typically in the range of approximately 10 eV to 20,000 eV. In some embodiments, the ion bombardment energy suitable for curing according to this disclosure is from about 50 eV to 4,000 eV. In one embodiment, the plasma potential is greater than the potential of electrode 208, and the high-energy secondary electrons emitted from electrode 208 are further accelerated by the shell voltage of the plasma as secondary electrons traverse the plasma.

[0054] At least a portion of the electron beam consists of a secondary electron flux emitted from electrode 208 due to high-energy ion bombardment of the electrode surface, which propagates through process space 201 and reacts with process gas near substrate 211. Suitable process gases, such as helium (He), argon (Ar), hydrogen (H2), and ammonia, are used.

[0055] An electron beam initiates a curing reaction on substrate 211 using a mixture of NH3, silane (Si2H6), methane (CH4), acetylene (C2H2), nitrogen trifluoride (NF3), tetrafluoromethane (CF4), sulfur hexafluoride (SF6), carbon monoxide (CO), trifluoromethane (CHF3), chlorine (Cl2), hydrogen bromide (HBr), nitrogen (N2), oxygen (O2), combinations thereof, and the like. In some embodiments, in addition to capacitively generated plasma, the electron beam also generates chemically reactive radicals and ions, which adsorb onto the surface of the substrate and form a chemically reactive layer on the surface of substrate 211. Electron beam bombardment of the chemically reactive layer induces the production of products, thereby causing substrate 211 to cure. In some embodiments, the chemically reactive polymer layer causes changes to the substrate, such as reduction (reduction or elimination of oxygen) or addition of nitrogen. In some embodiments, process gases are pre-selected to induce the desired substrate changes. For example, a nitrogen-containing process gas may be pre-selected to increase the nitrogen content of the substrate, for example, a dielectric material.

[0056] Therefore, the electron beam initiates a chemical reaction to release certain species (e.g., oxygen) from the substrate, or adds one or more species to the substrate (e.g., adding nitrogen to the dielectric material) and cures the substrate 211. The curing of the substrate 211 is also affected by other factors such as pressure, wafer or substrate temperature, electron beam energy, electron beam plasma power, and bias power (if required). In one embodiment, the pressure in the process space 201 is maintained between about 3.0 mTorr and about 100 mTorr during electron beam curing of the substrate 211. The pressure is generated by a vacuum pump 268 in fluid communication with the process space 201. The pressure is regulated by a gate valve 266 disposed between the process space 201 and the vacuum pump 268. The curing of the substrate 211 during electron beam curing is also affected by the substrate temperature. Suitable curing temperatures used herein include between 0 degrees Celsius and 500 degrees Celsius. The curing of the substrate 211 is also affected by the electron beam energy, which in some embodiments includes a peak energy of about 50 to 4000 eV. In some embodiments, the electron beam plasma power can be from about 100W to about 5000W. In some embodiments, the electron beam processing chamber is configured to provide a bias power from about 30W to about 5000W to the substrate.

[0057] In some embodiments, the RF bias power generator 262 is coupled to the electrode 244 of the base 210 via an impedance match 264. In another embodiment, a waveform tailoring processor 247 may be connected between the output of the impedance match 264 and the electrode 244. The waveform tailoring processor 247 modifies the waveform generated by the RF bias power generator 262 to a desired waveform. The ion energy of the plasma near the substrate 211 is controlled by the waveform tailoring processor 247. In some embodiments, the waveform tailoring processor 247 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. A controller 226 controls the waveform tailoring processor 247.

[0058] Figure 3 Another embodiment of the electron beam processing chamber 200' is schematically shown. Figure 2 In some implementations, VHF power (from RF power generator 220) and lower-frequency RF power (from RF power generator 222) are delivered to electrode 208 via separate paths. Figure 3 In this embodiment, the RF power generator 220 is coupled to the electrode 208 via a folded resonator 295 covering the edge of the electrode 208. A lower-frequency RF power generator 222 is coupled to the electrode 208 via an RF impedance match 294 and an RF feed conductor 223. A DC adsorption voltage supply 254 is coupled to the adsorption electrode 252 via a feed conductor 255 extending through a path in the top plate 206.

[0059] Figure 4 This is a schematic top view of the exemplary integrated system 400, which includes... Figure 1 The deposition processing chamber 100 shown and / or Figure 2 or Figure 3 One or more of the electron beam processing chambers 200 shown are incorporated into and integrated into the exemplary integrated system 400. In one embodiment, the integrated system 400 may be commercially available from Applied Materials, Inc., located in Santa Clara, CA. Integrated processing systems. Other processing systems (including those from other manufacturers) may be suitable for benefiting from this disclosure.

[0060] In some embodiments, the integrated system 400 includes, for example, a vacuum-sealed processing platform 404, a plant interface 402, and a system controller 444. The processing platform 404 includes at least one deposition processing chamber 100 (e.g., a...). Figure 1 The deposition processing chamber 100 shown), and at least one electron beam processing chamber 200 (e.g., one Figure 2 The diagram shows an electron beam processing chamber 200, a plurality of processing chambers 428, 420, 410, and at least one loading locking chamber 422 (the loading locking chamber is coupled to a vacuum substrate transfer chamber (e.g., transfer chamber 436)). Two loading locking chambers 422 are shown in... Figure 4 In the middle. The factory interface 402 is coupled to the transfer chamber 436 via the loading locking chamber 422.

[0061] In one embodiment, the factory interface 402 includes at least one base 408 and at least one factory interface robot 414 to facilitate the transfer of substrates. The base 408 is configured to receive one or more front-opening standard containers (FOUPs). Two FOUPs 406A-406B are shown. Figure 4 In this implementation, a factory interface robot 414, having blades 416 disposed at one end, is configured to transfer substrates from a factory interface 402 through a loading locking chamber 422 to a processing platform 404 for processing. Optionally, one or more processing chambers 410, 420, 428, deposition processing chamber 100, and electron beam processing chamber 200 may be connected to a terminal 426 of the factory interface 402 to facilitate processing of substrates from FOUP 406A-406B.

[0062] Each loading lock chamber 422 has a first port coupled to the factory interface 402 and a second port coupled to the transfer chamber 436. The loading lock chamber 422 is coupled to a pressure control system (not shown), which pumps down and vents the loading lock chamber 422 to facilitate the transfer of the substrate between the vacuum environment of the transfer chamber 436 and the generally surrounding environment (e.g., the atmosphere) of the factory interface 402.

[0063] The transfer chamber 436 has a vacuum robot 430 disposed therein. The vacuum robot 430 has blades 434, which are capable of transferring substrate 401 between the loading locking chamber 422, the deposition processing chamber 100, the electron beam processing chamber 200, and the processing chambers 410, 420, and 428.

[0064] In some embodiments of the integrated system 400, the integrated system 400 may include Figure 1The deposition processing chamber 100 and other processing chambers 410, 420, 428, electron beam processing chamber 200 and / or electron beam processing chamber 200' shown are illustrated. In some embodiments, processing chambers 410, 420, 428 may be deposition chambers, etching chambers, heat treatment chambers or other similar types of semiconductor processing chambers.

[0065] System controller 444 is coupled to processing system 400. System controller 444 may include or be included within computing device 441. System controller 444 controls the operation of processing system 400 using direct control of processing chambers 410, 420, 428, deposition processing chamber 100, and electron beam processing chamber 200 of integrated system 400. Alternatively, system controller 444 may control a computer (or controller) associated with processing chambers 410, 420, 428, deposition processing chamber 100, electron beam processing chamber 200, and integrated system 400. In operation, system controller 444 also enables data collection and feedback from the respective chambers and processing chambers (e.g., deposition processing chamber 100 and / or electron beam processing chamber 200) to optimize the performance of integrated system 400.

[0066] System controller 444 typically includes a central processing unit (CPU) 438, memory 440, and support circuitry 442. CPU 438 can be one of any type of general-purpose computer processor that can be used in an industrial environment. Support circuitry 442 is conventionally coupled to CPU 438 and may include cache, clock circuitry, input / output subsystems, power supplies, and the like. Software routines transform CPU 438 into a dedicated computer (controller) 444. Software routines may also be stored and / or executed by a second controller (not shown) located remotely from integrated system 400.

[0067] In some embodiments, this disclosure relates to an integrated system comprising: a vacuum substrate transport chamber; a deposition chamber configured for flowable chemical vapor deposition coupled to the vacuum substrate transport chamber; and a curing chamber coupled to the vacuum substrate transport chamber, wherein the curing chamber is configured to cure a dielectric material using an electron beam radiation source. In some embodiments, the curing chamber of the integrated system is configured to maintain the dielectric material at a temperature of 0°C to 500°C. In some embodiments, the curing chamber is configured to maintain the dielectric material at a pressure of 3 mTorr to 100 mTorr. In some embodiments, the curing chamber is configured to apply a bias power of 30 W to 5000 W to the dielectric material. In some embodiments, the curing chamber is configured to provide plasma power of 100 W to approximately 5000 W. In some embodiments, the curing chamber is configured to form an electron beam by a reaction comprising a process gas, the process gas including one or more of the following: helium.

[0068] (He), Argon (Ar), Hydrogen (H2), Ammonia (NH3), Dichlorosilane (Si2H6), Methane

[0069] The following are considered dielectric materials: (CH4), acetylene (C2H2), nitrogen trifluoride (NF3), tetrafluoromethane (CF4), sulfur hexafluoride (SF6), carbon monoxide (CO), trifluoromethane (CHF3), chlorine (Cl2), hydrogen bromide (HBr), nitrogen (N2), oxygen (O2), and combinations thereof. In some embodiments, the deposition chamber is configured to form the dielectric material at a temperature of 0°C to 100°C. In some embodiments, the deposition chamber is configured to form the dielectric material at a pressure of 100 mTorr to 5 Torr. In some embodiments, the deposition chamber is configured to form the dielectric material when a bias power of 30 W to 5000 W is applied to the dielectric material.

[0070] Figure 5 This is a flowchart depicting the operations of a method 500 for forming an integrated circuit structure according to an embodiment described herein. In operation 510, process gas is delivered to the process space of an electron beam processing chamber, for example... Figure 2 The electron beam processing chamber 200 contains a process space 201. Various process gases are supplied from the supplier 238 through the upper gas injector 230 and the lower gas injector 234 into the process space 201. These process gases include one or more of the following: helium (He), argon (Ar), hydrogen (H2), and ammonia.

[0071] (NH3), silane (Si2H6), methane (CH4), acetylene (C2H2), nitrogen trifluoride (NF3), tetrafluoromethane (CF4), sulfur hexafluoride (SF6), carbon monoxide (CO), trifluoromethane (CHF3), chlorine (Cl2), hydrogen bromide (HBr), nitrogen (N2), oxygen (O2), and combinations thereof. In one embodiment, an inert gas is also supplied to process space 201. In some embodiments, the inert gas is supplied through upper gas injector 230. Although not specifically addressed... Figure 2 The illustration shows an inert gas being delivered through a top electrode (e.g., electrode 208).

[0072] In operation 520, RF power, such as low-frequency RF power, is delivered to an electrode disposed in the process space. In one embodiment, the electrode is formed of a material with a high secondary electron emission coefficient and disposed in the process space. In one embodiment, low-frequency RF power having a frequency of approximately 2 MHz or approximately 13.56 MHz is applied to the top electrode (e.g., electrode 208). In some embodiments, the RF power is applied to the top electrode (e.g., electrode 208) in a pulsed manner. In some embodiments, the RF power is applied continuously to the top electrode (e.g., electrode 208). The RF power applied to the top electrode (e.g., electrode 208) is used to excite the process gas in the process space 201 and form a plasma in operation 530. By utilizing low-frequency RF power, a plasma with a high shell voltage can be generated, which is beneficial for accelerating electrons subsequently emitted from the top electrode (e.g., electrode 208).

[0073] In some embodiments, the base 210 is maintained at ground potential. In some embodiments, low-frequency RF power is applied to the base 210. In some embodiments, the RF power applied to the base 210 occurs simultaneously with the RF power applied to the electrode 208. Alternatively, RF power is delivered to the base 210 when substantially no RF power is applied to the electrode 208. In some embodiments where RF power is applied to the base 210, the RF power is controlled to reduce adverse effects on the plasma shell potential to prevent delays in electron beam arrival at the substrate 211.

[0074] In some embodiments, the RF power applied to the top electrode (e.g., electrode 208) can be synchronized with the RF power applied to the base 210 by pulse, such that the duty cycles of the top electrode RF power and the base 210 RF power do not overlap. Therefore, the electrical bias voltage within the process space 201 is not substantially limited, and the delay of the electron beam due to the plasma shell bias potential is substantially mitigated.

[0075] In operation 540, the electrode is bombarded with ions from plasma. In some embodiments, the plasma has a predominantly positive charge, while the top electrode (e.g., electrode 208) has a predominantly negative charge. Ions from the plasma are influenced by an electric field generated in process space 201, and the accelerated ions toward the top electrode (e.g., electrode 208) heat the top electrode (e.g., electrode 208). Because the top electrode is formed of a material with a high secondary electron emission coefficient, the ion bombardment of the top electrode (e.g., electrode 208) causes electrons to be emitted from the top electrode (e.g., electrode 208).

[0076] In operation 550, electrons emitted from the electrodes are accelerated toward the substrate. For example, electrons emitted from the top electrode (e.g., electrode 208) are accelerated toward the substrate 211. Due to the generally negative charge of the top electrode (e.g., electrode 208), the negatively charged electrons are repelled by the top electrode (e.g., electrode 208) and move toward the substrate 211. In some embodiments, the plasma shell voltage potential further serves to accelerate the electrons toward the substrate 211. When electrons are accelerated by the plasma shell voltage, they gain energy between about 50 electron volts (eV) and about 4,000 eV upon entering the plasma. The electrons emitted from the top electrode (e.g., electrode 208) generate a large-area secondary electron beam. The electron beam has a generally uniform energy distribution across the diameter of the substrate 211. In some embodiments, the electron beam contacts the substrate, for example, a dielectric material, to cure the dielectric material. For example, the material of the substrate (e.g., the dielectric material) is cured upon contact with the electron beam.

[0077] In some embodiments, electrons in the electron beam react with process gases to further generate additional free radicals and ions adsorbed onto the surface of substrate 211. In some embodiments, the adsorbed material forms a chemically reactive layer on the substrate surface. In some embodiments, the electron beam alters the composition of substrate 211. For example, in some embodiments, substrate 211 includes a dielectric material that can form an oxide nitride layer upon contact with air. For example, hydrogen-containing silicon nitride may problematically form an oxide nitride layer, such as silicon oxynitride, wherein the silicon oxynitride is characterized by SiO2. x N y For example, SiO₂ with 1 ≤ x ≤ 2 and 1 ≤ y ≤ 2 x N y In some embodiments, x (=O / Si) and y (=N / Si). In these embodiments, silicon oxynitride is characterized by SiO₂. x N yFurthermore, curing the dielectric material or contacting it with an electron beam decreases x and increases y. For example, during curing, the ratio of y to x is changed such that the ratio of y to x is greater than 1 compared to silicon oxynitride before curing or contact with an electron beam as described herein. In some embodiments, according to this disclosure, the atomic ratio of y to x is changed to be greater than 1 during curing or contact with an electron beam. In some embodiments, silicon oxynitride is characterized by (SiO₂) x N y Curing the dielectric material or contacting it with an electron beam reduces the atomic percentage of oxygen and / or increases the atomic percentage of nitrogen. In some embodiments, according to this disclosure, during curing or contact with an electron beam, (SiO2) x N y (x>y) is changed to (SiO) x N y (y>x). In some embodiments, during curing, the dielectric material is maintained at a temperature of 0°C to 500°C, for example, 100°C to 400°C, or 200°C to 300°C. In some embodiments, during curing, the dielectric material is maintained at a pressure in a process chamber ranging from about 3 to about 100 mTorr, for example, 10 mTorr to 75 mTorr. In some embodiments, during curing, the dielectric material is subjected to a bias power of 30 to 5000 W. In some embodiments, curing according to this disclosure prevents the formation of oxynitrides, such as silicon oxynitride.

[0078] In some embodiments, a process gas is pre-selected to modify the dielectric layer as needed. For example, the process gas may be selected from one or more of the following: helium (He), argon (Ar), hydrogen (H2), ammonia (NH3), silane (Si2H6), methane (CH4), acetylene (C2H2), nitrogen trifluoride (NF3), tetrafluoromethane (CF4), sulfur hexafluoride (SF6), carbon monoxide (CO), trifluoromethane (CHF3), chlorine (Cl2), hydrogen bromide (HBr), nitrogen (N2), oxygen (O2), and combinations thereof. In one embodiment, ammonia (NH3) is used to increase the nitrogen content of the dielectric layer. In another embodiment, silane (Si2H6) is used to increase the silicon content of the dielectric layer.

[0079] In some embodiments, substrate 211 is a dielectric material layer or film, such as an oxide nitride layer, and may include silicon nitride, and may include oxygen and nitrogen. The inventors have found that the amount of oxygen negatively affects the stability of the deposited film (e.g., a film formed by FCVD). In some embodiments, the oxygen-to-nitrogen ratio may affect the resistance of the semiconductor device. For example, a small amount of oxygen compared to nitrogen in the dielectric layer promotes stability and reduces the resistance of the dielectric layer. For example, the desired post-curing target dielectric layer material may include silicon and nitrogen or consist substantially of silicon and nitrogen.

[0080] In some embodiments, the curing processes described herein are useful for forming interconnect devices and are advantageous in cases where dielectric materials are deposited on a substrate via a flowable chemical vapor deposition (FCVD) process. Therefore, this disclosure includes depositing dielectric materials in features with high aspect ratio trenches, for example, for semiconductor devices (particularly for three-dimensional (3D) stacks of semiconductor chips). In one embodiment, the deposition process may use remote plasma along with RF bias power supplied in a pulsed mode to a substrate support assembly on which the substrate is placed. In some embodiments, the deposition process is performed without the generation of internal source power within the chamber. Remotely generated remote plasma and pulsed RF bias power may be supplied simultaneously, alternately, or sequentially to the internal processing region of the processing chamber as desired to provide good gap-filling capability for the dielectric material filling the trenches from the substrate. In embodiments, the deposition process including FCVD begins with placing a substrate (e.g., Figure 1 The substrate 301 is transferred to the deposition process chamber, for example... Figure 1 The deposition chamber 100 shown is illustrated. The substrate 301 may have a generally flat surface, a non-flat surface, or a generally flat surface with structures formed on its surface. Figure 7A In the illustrated embodiment, substrate 301 has a patterned material layer 704 disposed on interface layer 702. In one embodiment, patterned material layer 704 includes openings 708 formed in patterned material layer 704. Patterned material layer 704 can be used to form gate structures, contact structures, interconnect structures in front-end or back-end processes, or any suitable structure as required. In one embodiment, a deposition process such as FCVD can be performed on patterned material layer 704 to form contact structures in patterned material layer 704. Substrate 301 can be a material such as crystalline silicon (e.g., Si). <100> or Si <111> The substrate 301 can be made of various materials, including silicon oxide, strained silicon, silicon germanium, doped or undoped polycrystalline silicon, doped or undoped silicon wafers and patterned or unpatterned silicon-on-insulator (SOI) wafers, carbon-doped silicon oxide, silicon nitride, doped silicon, germanium, gallium arsenide, glass, and sapphire. The substrate 301 can have various sizes, such as wafers with diameters of 200 mm, 300 mm, 450 mm, or other diameters, and rectangular or square panels. Unless otherwise stated, the embodiments and examples described herein are performed on substrates having diameters of 200 mm, 300 mm, or 450 mm. In embodiments where an SOI structure is used for the substrate 301, the substrate 301 may include a buried dielectric layer disposed on a crystalline silicon substrate. In the embodiments described herein, the substrate 301 may be a crystalline silicon substrate.

[0081] In one embodiment, interface layer 702 may be a dielectric layer. Patterned material layer 704 has an opening 708 that exposes a portion 710 of interface layer 702 for depositing dielectric material in the portion 710. The opening 708 described herein may include trenches, vias, openings, and the like. In one embodiment, patterned material layer 704 may be a metallic material, a silicon-containing material, a carbon-containing material, or other suitable material. Suitable examples of metallic materials include copper-containing materials, aluminum-containing materials, nickel-containing materials, tungsten-containing materials, or other metallic materials. Suitable silicon-containing materials include silicon, silicon oxide, silicon nitride, silicon oxynitride, and combinations thereof. Suitable carbon-containing materials include silicon carbide, amorphous carbon, or the like. In the exemplary embodiment described herein, patterned material layer 704 is a silicon layer.

[0082] Interface layer 702 may be a dielectric layer, such as a dielectric oxide layer or a dielectric nitride layer as desired. Interface layer 702 may include multiple layers, composite layers, or a single layer. Other suitable materials for the dielectric layer include undoped silicon glass (USG), such as silicon oxide or TEOS, borosilicate glass (BSG), phosphosilicate glass (PSG), borophosphosilicate glass (BPSG), silicon nitride, amorphous silicon, and combinations thereof.

[0083] In one implementation, such as Figure 7A As shown, the patterned material layer 704 can be patterned to a predetermined depth to expose a portion 710 of the interface layer 702. The material layer 704 can be etched or patterned using any suitable patterning process. The patterned material layer 704 can be patterned by supplying a gas mixture into the processing chamber and applying a predetermined RF power level to the processing chamber.

[0084] In this embodiment, the deposition gas mixture is supplied to the processing chamber (e.g., Figure 1 In the deposition processing chamber 100, a deposition process is performed to form dielectric material 706 in the opening 708. Figure 7B(As shown in the diagram). The gas mixture supplied to the deposition chamber 100 can be varied based on the type of material to be formed and filled in the opening 708. In one example, when the dielectric material 706 to be formed is a silicon nitride layer, the supplied deposition gas mixture includes at least one silicon-containing gas, a nitrogen-containing gas, or optionally an inert gas. In another example, when the dielectric material 706 to be formed is a silicon oxide layer, the supplied deposition gas mixture includes at least one silicon-containing gas, an oxygen-containing gas, or optionally an inert gas. In yet another example, when the dielectric material 706 to be formed is a silicon carbide layer, the supplied deposition gas mixture includes at least one silicon-containing gas, a carbon-containing gas, or optionally an inert gas. In still another example, when the dielectric material 706 to be formed is a carbide layer, the supplied deposition gas mixture includes at least one carbon-containing gas or optionally an inert gas.

[0085] Suitable examples of silicon-containing gases include silanes (SiH4), tetraethoxysilanes (TEOS), disilanes (Si2H6), and the like. Suitable examples of nitrogen-containing gases include nitrogen (N2), ammonia (NH3), nitrous oxide (N2O), nitrogen dioxide (NO2), and the like. Suitable examples of oxygen-containing gases include hydrogen peroxide (H2O2), water (H2O), oxygen (O2), ozone (O3), and the like. Suitable examples of carbon-containing gases include CO2, hydrocarbon gases (such as methane (CH4) and ethane (C2H6)), and the like. Suitable examples of inert gases include helium (He), argon (Ar), and the like.

[0086] In some instances, carrier gases such as nitrogen (N2), hydrogen (H2), and the like may also be supplied to the deposition gas mixture as needed.

[0087] In one example, the deposition gas mixture includes a silicon-containing gas, a nitrogen- or carbon-containing gas, and an argon (Ar) or hydrogen (H2) gas. In a particular example, the deposition gas mixture includes silane (SiH4), argon (Ar) or helium (He), ammonia (NH3), hydrogen (H2) or nitrogen (N2), or a combination thereof, to deposit a silicon nitride layer as the dielectric material 706. In another particular example, the deposition gas mixture includes SiH4, Ar or He, CH4 or CO2, H2 or N2, to deposit a silicon carbide layer as the dielectric material 706. In yet another particular example, the deposition gas mixture includes SiH4, Ar or He, O2 or NO2, to deposit a silicon oxide layer as the dielectric material 706.

[0088] In one embodiment, the flow rate of the silicon-containing gas is controlled between about 30 sccm and about 500 sccm (by volume). The flow rate of the oxygen, carbon, or nitrogen-containing gas is controlled between about 50 sccm and about 2000 sccm (by volume). The flow rate of the argon (Ar) or helium (He) gas is controlled between about 250 sccm and about 2000 sccm (by volume).

[0089] In one embodiment, some gases from the deposition gas mixture may be supplied from gas source 106 to the internal processing region 151 via remote plasma source 104, while some gases may be supplied from the side of the deposition processing chamber 100, such as a fluid source 119 laterally formed around nozzle 118, to be delivered to the internal processing region 151. In some instances, a first gas (e.g., a reactive precursor) from the deposition gas mixture (e.g., a silicon-containing gas) is supplied from the side of the deposition processing chamber 100 (e.g., fluid source 119), while a second gas from the deposition gas mixture (such as a carrier gas, an inert gas, a carbon or nitrogen-containing gas, or other gas) is supplied from gas source 106 to the internal processing region 151 via remote plasma source 104. In one instance, the first gas is SiH4 gas supplied into the processing chamber from fluid source 119, and the second gas is at least one of Ar, He, NH3, H2, N2, or a combination thereof supplied from gas source 106 to the internal processing region 151 via remote plasma source 104.

[0090] In the implementation method, the deposition gas mixture is supplied to Figure 1 After the processing chamber, remote plasma source power is applied to remote plasma source 104 to generate remote plasma, which is then transported from remote plasma source 104 to internal processing region 151. In some embodiments, remotely dissociated gases and / or other gases provide high-density and low-energy atomic species compared to conventional chamber RF source power applied to the nozzle (which can provide high-energy but relatively low-density gas radicals). Therefore, by utilizing a remote plasma source with certain activated gas species along with a side-flow source (e.g., self-flowing source 119) to supply gas, a high-density gas species with relatively low-energy atomic species is subsequently transported to internal processing region 151 to form dielectric material 706 on substrate 301, such as... Figure 7B As shown in the figure. In some embodiments, atomic gas species from a remote plasma source are more reactive and can react more efficiently, slowly and thoroughly with reactive gas precursors provided from the side (e.g., from fluid source 119), thus providing good gap-filling capability to fill the openings 708 defined in the patterned material layer 704 with dielectric material 706.

[0091] In implementation methods, the introduced parameters can be changed and adjusted. Figure 1 The amount of each gas in the processing chamber is adjusted to accommodate, for example, the thickness of the dielectric material 706 to be formed in the opening 708 (e.g., the height or geometry of the opening 708). In one or more embodiments, the gases supplied from the remote plasma source 104 may have certain ratios. For example, the ratio of nitrogen- or carbon-containing gas to Ar gas by volume may be controlled between about 0.2:1 and about 2:1.

[0092] In one example, a remote RF source power of approximately 1000 watts to approximately 10000 watts (e.g., between approximately 500 watts and approximately 3000 watts) is supplied to a remote plasma source 104 to generate a remote plasma to be delivered to an internal processing region 151. In some embodiments, microwave energy is used herein. The frequency of the power applied to the remote plasma source 104 is approximately 400 kHz. This frequency can be in the range of approximately 50 kHz to approximately 2.45 GHz. The substrate temperature is maintained between approximately -20 degrees Celsius and approximately 200 degrees Celsius, for example, between approximately 20 degrees Celsius and approximately 90 degrees Celsius.

[0093] In some deposition implementations, while supplying remote plasma from remote plasma source 104 to internal processing region 151, pulsed RF bias power can be applied to substrate support member 152 to generate RF bias power to substrate 301 disposed on substrate support member 152. In some implementations, the RF bias power generated to substrate support member 152 is used to assist in providing directionality to the plasma in internal processing region 151 during the deposition process. In some implementations, RF bias power can be provided at 60 MHz and / or 2 MHz as needed. In one particular implementation, RF bias power is provided at 60 MHz, 2 MHz, or 400 kHz.

[0094] In some embodiments, RF bias power can be supplied to the substrate support member 152 in a pulsed mode. In some embodiments, the RF bias power supplied in a pulsed mode can provide a relatively mild RF power level to the substrate 301 disposed on the substrate support member, thereby accelerating reactive species toward the substrate 301 at a relatively mild energy level. The RF bias power supplied to the substrate support member 152 can be used simultaneously, in parallel, separately, alternately, or sequentially with the remote plasma power supplied from the remote plasma source 104.

[0095] After forming the dielectric material 706, the workpiece can be moved... Figure 2 or Figure 3 The process chamber is used for curing or modification to stabilize the dielectric material, such as dielectric material 706. Now refer to... Figure 6, Figure 6 This is a flowchart describing the operation of a method 600 for curing a dielectric layer, the method including, in operation 610, contacting the dielectric material with an electron beam under conditions sufficient to cure the dielectric material. In some embodiments, conditions sufficient to cure the dielectric material include those described above. Figure 5 The same conditions mentioned. For example, in order to cure the dielectric layer according to an embodiment of this disclosure, process gas is delivered to the process space of the electron beam processing chamber, for example... Figure 2 The electron beam processing chamber 200 has a process space 201. Various process gases are supplied from the supplier 238 through the upper gas injector 230 and the lower gas injector 234 to the process space 201. These process gases include one or more of the following: helium (He), argon (Ar), hydrogen (H2), ammonia (NH3), silane (Si2H6), methane (CH4), acetylene (C2H2), nitrogen trifluoride (NF3), tetrafluoromethane (CF4), sulfur hexafluoride (SF6), carbon monoxide (CO), trifluoromethane (CHF3), chlorine (Cl2), hydrogen bromide (HBr), nitrogen (N2), oxygen (O2), and combinations thereof. In one embodiment, an inert gas is also supplied to the process space 201. In some embodiments, the inert gas is supplied through the upper gas injector 230. Although not specifically addressed... Figure 2 The illustration shows an inert gas, but in another embodiment, the inert gas is delivered through a top electrode (e.g., electrode 208). By injecting an inert gas, the likelihood of reactive species returning to diffuse can be reduced, and the integrity of the plasma formed in the process space can be better maintained.

[0096] In some curing embodiments, low-frequency RF power is delivered to electrodes disposed in a process space. In one embodiment, the electrodes are formed of a material with a high secondary electron emission coefficient and disposed in the process space. In one embodiment, RF power having a frequency of approximately 2 MHz or approximately 13.56 MHz is applied to a top electrode (e.g., electrode 208). In another embodiment, the RF power is applied to the top electrode, such as electrode 208, in a pulsed manner. By utilizing low-frequency RF power, plasma with a high shell voltage can be generated, which is beneficial for accelerating electrons subsequently emitted from the top electrode (e.g., electrode 208).

[0097] In one embodiment, the substrate 210 is maintained at ground potential during curing. In another embodiment, low-frequency RF power is applied to the substrate 210. In some embodiments, the RF power applied to the substrate 210 occurs simultaneously with the RF power applied to the electrode 208. Alternatively, RF power is delivered to the substrate 210 when substantially no RF power is applied to the electrode 208. In embodiments where RF power is applied to the substrate 210, the RF power is controlled to reduce adverse effects on the plasma shell potential, thereby preventing delays in electron beam arrival at the substrate 211.

[0098] In some embodiments, the RF power applied to the top electrode (e.g., electrode 208) can be synchronized with the RF power applied to the base 210 by pulse, such that the duty cycles of the top electrode RF power and the base 210 RF power do not overlap. Therefore, the electrical bias voltage within the process space 201 is not substantially limited, and the delay of the electron beam due to the plasma shell bias potential is substantially reduced.

[0099] In some embodiments, the electrodes are bombarded with ions from plasma. In some embodiments, the plasma has a predominantly positive charge, while the top electrode (e.g., electrode 208) has a predominantly negative charge. The ions from the plasma are influenced by an electric field generated in process space 201, and the ions accelerated toward the top electrode (e.g., electrode 208) heat the top electrode (e.g., electrode 208). Because the top electrode is formed of a material with a high secondary electron emission coefficient, the ion bombardment of the top electrode (e.g., electrode 208) causes electrons to be emitted from the top electrode (e.g., electrode 208).

[0100] In some embodiments, electrons emitted from the electrodes are accelerated toward the substrate. For example, electrons emitted from the top electrode (e.g., electrode 208) are accelerated toward the substrate 211. Due to the generally negative charge of the top electrode (e.g., electrode 208), the negatively charged electrons are repelled by the top electrode (e.g., electrode 208) and move toward the substrate 211. In some embodiments, the plasma shell voltage potential further accelerates the electrons toward the substrate 211. When electrons are accelerated by the plasma shell voltage, they gain energy between approximately 50 electron volts (eV) and approximately 4,000 eV upon entering the plasma. The electrons emitted from the top electrode (e.g., electrode 208) generate a large-area secondary electron beam. The electron beam has a generally uniform energy distribution across the diameter of the substrate 211.

[0101] In some embodiments, the temperature of the dielectric material is between 0°C and 500°C throughout the curing process of this disclosure. In some embodiments, the dielectric material is maintained at a pressure of, for example, 3 to 100 millitor in the process chamber. In some embodiments, a bias power of 30 to 5000 W is applied to the dielectric material during curing according to this disclosure.

[0102] In some embodiments, this disclosure includes a method for curing a dielectric layer, comprising the steps of: contacting the dielectric material with an electron beam under conditions sufficient to cure the dielectric material. In some embodiments, the dielectric material is an oxide nitride layer. In some embodiments, the oxide nitride layer is a silicon nitride film. In some embodiments, curing the dielectric material reduces the oxygen content of the silicon nitride film and increases the nitrogen content of the silicon nitride film. In some embodiments, the nitrogen to oxygen ratio after curing is greater than 1. In some embodiments, the temperature of the dielectric material is from 0 degrees Celsius to 500 degrees Celsius. In some embodiments, the dielectric material is disposed in a process chamber with a pressure of 3 to 100 millitor. In some embodiments, an electron beam is formed from a reaction involving process gases, which include one or more of the following: helium (He), argon (Ar), hydrogen (H2), ammonia (NH3), silane (Si2H6), methane (CH4), acetylene (C2H2), nitrogen trifluoride (NF3), tetrafluoromethane (CF4), sulfur hexafluoride (SF6), carbon monoxide (CO), trifluoromethane (CHF3), chlorine (Cl2), hydrogen bromide (HBr), nitrogen (N2), oxygen (O2), and combinations thereof. In some embodiments, curing further includes providing a bias power of 30 to 5000 W to the dielectric material.

[0103] In some embodiments, post-deposition electron beam curing can improve film composition and stability (e.g., of the dielectric material). In some embodiments, post-deposition electron beam curing is performed in a nitrogen atmosphere, which increases the N:Si ratio by at least 2 times, reduces the oxygen content by at least 2 times, reduces or eliminates moisture adsorbed into the dielectric material, and is suitable for bulk film composition.

[0104] In one embodiment, one or more controllers may be directly (not shown) or via a computer (or controller) associated with the process chamber and / or support system, and individually or jointly with the integrated system 400 and the support system, coupled to the deposition processing chamber 100 and the electron beam processing chamber 200. In one embodiment, the controller may be one of any form of general-purpose computer processor that can be used in an industrial environment to control various chambers and subprocessors. The computer-readable medium that may include memory or the CPU includes one or more readily available memories, such as random access memory (RAM), read-only memory (ROM), floppy disks, hard disks, or any other form of local or remote digital storage device. In one embodiment, support circuitry is coupled to the CPU to support the processor in a conventional manner. This circuitry includes caches, power supplies, clock circuitry, input / output circuitry systems and subsystems, and the like.

[0105] In some embodiments, this disclosure relates to a non-transitory computer-readable medium having specified instructions stored on the medium that, when executed, cause a method for forming an integrated circuit structure, the method comprising the steps of: delivering a process gas to a process space of a process chamber; applying RF power to electrodes formed of a material with a high secondary electron emission coefficient and disposed in the process space; generating a plasma comprising ions in the process space; bombarding the electrodes with ions to cause the electrodes to emit electrons and form an electron beam; and contacting a dielectric material with the electron beam to cure the dielectric material.

[0106] In some embodiments, this disclosure relates to a non-transitory computer-readable medium having instructions stored on the medium that, when executed, cause a method for curing a dielectric material, the method comprising the steps of: delivering a process gas to a process space of a process chamber; applying RF power to electrodes formed of a material with a high secondary electron emission coefficient and disposed in the process space; generating a plasma comprising ions in the process space; bombarding the electrodes with ions to cause the electrodes to emit electrons and form an electron beam; and contacting the dielectric material with the electron beam to cure the dielectric material. In some embodiments, the dielectric material is a flowable chemical vapor deposition product, such as SiN or SiN having hydrogen incorporated into the chemical vapor deposition product.

[0107] In some embodiments, this disclosure relates to a non-transitory computer-readable medium having instructions stored on the medium that, when executed, cause a method for curing a dielectric layer, the method comprising the step of contacting the dielectric material with an electron beam under conditions sufficient to cure the dielectric material. In some embodiments, the dielectric material is a flowable chemical vapor deposition product, such as SiN or SiN having hydrogen incorporated into the chemical vapor deposition product.

[0108] Although the foregoing describes an implementation of this disclosure, other and further implementations of this disclosure may be designed without departing from the basic scope of this disclosure.

Claims

1. A method for forming an integrated circuit structure, comprising the following steps: The process space that delivers process gases to the process chamber; RF power is applied to electrodes disposed in the process space, the electrodes being formed of a material with a high secondary electron emission coefficient; A plasma comprising ions is generated in the process space; The electrode is bombarded with the ions to cause the electrode to emit electrons and form an electron beam; and The dielectric material is contacted with the electron beam to cure the dielectric material, wherein the dielectric material is a flowable chemical vapor deposition product, and wherein contacting the dielectric material with the electron beam reduces the atomic oxygen percentage of the dielectric material and increases the atomic nitrogen percentage of the dielectric material.

2. The method of claim 1, wherein the dielectric material is a nitride layer.

3. The method of claim 2, wherein the oxide nitride layer is silicon oxynitride, and wherein the silicon oxynitride is characterized by SiO₂. x N y , where x is a number greater than or equal to 1 and less than or equal to 2, and y is a number greater than or equal to 1 and less than or equal to 2.

4. The method of claim 3, wherein after curing, the ratio of y to x is greater than 1.

5. The method according to any one of claims 1 to 3, wherein the dielectric material is at a temperature of 0 degrees Celsius to 500 degrees Celsius.

6. The method according to any one of claims 1 to 3, wherein the pressure in the process chamber is 3 to 100 millitors.

7. The method according to any one of claims 1 to 3, wherein the process gas comprises one or more of the following: helium (He), argon (Ar), hydrogen (H2), ammonia (NH3), silane (Si2H6), methane (CH4), acetylene (C2H2), nitrogen trifluoride (NF3), tetrafluoromethane (CF4), sulfur hexafluoride (SF6), carbon monoxide (CO), trifluoromethane (CHF3), chlorine (Cl2), hydrogen bromide (HBr), nitrogen (N2), or oxygen (O2).

8. The method of any one of claims 1 to 3, further comprising the following steps: A bias power of 30 W to 5000 W is provided to the dielectric material.

9. The method of any one of claims 1 to 3, further comprising the following steps: The dielectric material is deposited on the substrate via flowable chemical vapor deposition.

10. A computer-readable medium having instructions stored on the computer-readable medium, the instructions, when executed, causing a process chamber to perform a method for forming an integrated circuit structure, the method as described in any one of claims 1 to 9.

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