Ion trap with inclined holes for substrate processing systems

Abstract

We provide an ion trap for use in substrate processing systems. [Solution] The ion trap may have at least one pore. The pore may have an inner surface that is inclined with respect to the top or bottom surface of the ion trap. The pore may prevent plasma ions from passing through the ion trap and / or allow plasma radicals to pass through the ion trap.

Description

Technical Field

[0001] The present disclosure relates to a substrate processing system, and more specifically, to an ion trap of a substrate processing system that performs radical enhanced atomic layer deposition.

Background Art

[0002] Atomic layer deposition (ALD) is a method of depositing a thin film on the surface of a substrate by exposing the substrate to two or more vapor-phase chemical reactants or precursors. ALD can provide uniform and conformal coverage of the substrate and precise control over the film thickness. However, the ALD process is generally slow and / or highly dependent on the temperature in the reaction chamber and / or the temperature of the substrate. If the temperature of the substrate or the chamber is too high, desorption of the chemisorbed layer may occur. If the temperature is too low, the deposition reaction may be too slow and the reaction may not proceed to completion or may not proceed at all, leading to a degradation in film quality. Thus, the narrow temperature window can limit the number of suitable precursors in conventional thermal ALD processes.

[0003] Plasma enhanced ALD (PE-ALD) can be used to overcome some of the limitations of the thermal ALD process. PE-ALD can use radical species generated by exposing precursors to a plasma as reactants in the ALD process. The use of energetic radicals as reactants increases the reactivity on the surface of the substrate, enables lower temperature processing, allows for a wider selection of precursors with higher thermal and chemical stability, and can often provide improved film properties (e.g., density, impurity levels, and electronic properties).

[0004] Various reactor configurations can be employed to influence the type and density of plasma species interacting with the substrate. In direct PE-ALD, the precursor is exposed to the plasma in close proximity to the substrate surface, where it can form energy radicals, ions, etc. The flux of energy radicals in close proximity to the substrate may be high, enabling uniform film formation and short plasma exposure times, but plasma-induced damage and anisotropy in the film can also occur due to the substrate surface's exposure to ions. In remote PE-ALD, the plasma may be located further away from the substrate surface, reducing but not removing the flux of ions to the substrate surface. In contrast, in another type of PE-ALD, radical-enhanced ALD (RE-ALD), ions can be prevented from reaching the substrate surface. This RE-ALD approach can avoid the plasma-induced damage and anisotropy often associated with PE-ALD processes, while still offering advantages in reactivity compared to thermal ALD processing.

[0005] Ions can be prevented from reaching the substrate surface in RE-ALD by providing an electrically grounded ion trap between the substrate and the reaction space where the plasma is supplied. Such ion traps may have pores that allow radical species to pass over the substrate surface while trapping ions. However, pores in the ion trap do not trap all ions, and some ions may pass through the ion trap, potentially negating some of the advantages of RE-ALD. Furthermore, pores in the ion trap may provide a large surface area for trapped ions and radicals to combine, thereby reducing the number of radicals that pass through the ion trap and come into contact with the substrate surface. Therefore, an ion trap design that increases the efficiency of the ion trap and reduces the possibility of ions and radicals combining while radicals pass through the ion trap may be desirable.

[0006] All considerations, including the discussion of problems and solutions described in this section, are included in this disclosure solely for the purpose of providing context for this disclosure. Such considerations should not be construed as acknowledging that any or all of the information above is publicly known or constitutes prior art at the time the invention was made. [Overview of the Initiative]

[0007] This summary is provided to introduce some concepts in a simplified form. These concepts are described in more detail below in the detailed description of the exemplary embodiments of this disclosure. This summary is not intended to identify any major or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

[0008] The reactor systems disclosed herein may include an ion trap that facilitates increased efficiency in capturing ions and / or reduces the likelihood of radicals binding on the surface of the ion trap as they pass through it. The reactor systems described herein may include a susceptor configured to support a substrate; a precursor distribution system located above the susceptor and configured to supply one or more precursors into the reaction chamber of the reactor system; a radio frequency (RF) power supply configured to supply RF power for generating ions and radicals from one or more precursors within the reaction chamber; and an ion trap located between the susceptor and the precursor distribution system. The ion trap may include at least one pore, the at least one pore may include an inner surface inclined with respect to the top or bottom surface of the ion trap. The inclined inner surface may be configured to prevent ions from passing through the ion trap and contacting the substrate, and / or to allow radicals to pass through the ion trap.

[0009] In various embodiments, the inner surface of the pore can be angled in the range of 70 to 85 degrees with the upper or lower surface of the ion trap.

[0010] In various embodiments, the pores may have openings on the top or bottom surface of the ion trap, and / or the openings may include a circular shape with a diameter in the range of 0.1 to 5 millimeters. In various embodiments, the pores may be formed as oblique cylinders, and the oblique cylinders may include aspect ratios in the range of 1 to 400. In various embodiments, the pores may have openings on the top or bottom surface of the ion trap, and the openings may include a circular, square, rectangular, or parallelogram shape.

[0011] In various embodiments, the opening may include a rectangular shape having a width in the range of 0.1 to 5 millimeters. In various embodiments, the opening may include a helical shape having a width in the range of 0.1 to 5 millimeters. In various embodiments, the ion trap may have a thickness in the range of 5 to 40 millimeters.

[0012] In various embodiments, the ion trap may have a plurality of holes having an inner surface inclined with respect to the top or bottom surface of the ion trap, and the plurality of holes may be parallel to each other.

[0013] In various embodiments, the reactor system may further include a power supply electrically connected to at least one of the susceptor and precursor distribution systems, and / or a controller configured to activate the power supply and apply a voltage bias across the susceptor and precursor distribution systems, thereby enabling ions and radicals to move perpendicularly toward the susceptor. In various embodiments, an ion trap may be connected to a ground connection.

[0014] This disclosure describes an ion trap for a reaction chamber, wherein the ion trap may have a plurality of pores. The inner surface of each of the plurality of pores may be inclined with respect to the top or bottom surface of the ion trap. The plurality of pores may be configured to block ions from passing through the ion trap and / or allow radicals to pass through the ion trap. The inner surface of each of the plurality of pores may be at an angle in the range of 70 to 85 degrees with respect to the top or bottom surface of the ion trap.

[0015] In various embodiments, each of the multiple pores may have a slanted cylindrical shape with a diameter in the range of 0.1 to 5 millimeters and / or an aspect ratio in the range of 1 to 400. In various embodiments, each of the multiple pores may have a rectangular cross-section with a width in the range of 0.1 to 5 millimeters. In various embodiments, the multiple pores may be parallel to each other. In various embodiments, the ion trap may have a thickness in the range of 5 to 40 millimeters.

[0016] The disclosure describes an ion trap for a reaction chamber, wherein the ion trap may have a pore having a helical cross-section. The inner surface of the helical pore may be inclined with respect to the top or bottom surface of the ion trap. The helical pore may be configured to prevent ions from passing through the ion trap and / or to allow radicals to pass through the ion trap.

[0017] For the purpose of outlining the benefits achieved beyond this disclosure and the prior art, specific purposes and benefits of this disclosure are described above. Naturally, it should be understood that not all of these purposes or benefits are necessarily achieved by any particular embodiment of this disclosure. Therefore, a person skilled in the art will recognize that embodiments disclosed herein may be implemented in a manner that achieves or optimizes one or more benefits taught or suggested herein, without necessarily achieving other purposes or benefits that may be taught or suggested herein.

[0018] All of these embodiments are intended to be within the scope of this disclosure. These embodiments and other embodiments will be readily apparent to those skilled in the art from the following detailed description of certain embodiments with reference to the accompanying drawings, and this disclosure is not limited to any particular embodiment(s) considered.

[0019] This specification specifically identifies and concludes in the claims that are to be embodiments of the present disclosure, although the merits of the embodiments of the present disclosure may be more readily apparent from the descriptions of certain embodiments of the present disclosure when read in conjunction with the accompanying drawings. Elements that are given the same reference numerals throughout the drawings are intended to be the same.

[0020] The accompanying drawings are incorporated herein and form part thereof to illustrate several embodiments of the present disclosure. The drawings presented herein are not intended to represent the actual appearance of any particular material, structure, or device, but are merely idealized representations used to describe embodiments of the present disclosure. It should be noted that elements in the drawings are illustrative for simplification and clarity and are not necessarily drawn to actual size. For example, the dimensions of some elements in the drawings may be exaggerated compared to others to help improve understanding of the illustrated embodiments of the present disclosure. The drawings, together with the descriptions, illustrate the principles of the present disclosure. The drawings may simply illustrate preferred alternative embodiments of the methods of fabrication and use of the present disclosure and should not be construed as limiting the present disclosure to only the illustrated and described embodiments. Further configurations and advantages will become apparent from the following more detailed descriptions of the various aspects, embodiments, and configurations of the present disclosure, as illustrated by the drawings referenced below. [Brief explanation of the drawing]

[0021] [Figure 1] This is a schematic diagram of an exemplary reactor system according to various embodiments. [Figure 2A]Exemplary ion traps of a reactor system according to various embodiments are shown. [Figure 2B] Exemplary ion traps of a reactor system according to various embodiments are shown. [Figure 2C] Exemplary ion traps of a reactor system according to various embodiments are shown. [Figure 3A] Exemplary ion traps having inclined holes according to various embodiments are shown. [Figure 3B] Exemplary ion traps having inclined holes according to various embodiments are shown. [Figure 3C] Exemplary ion traps having inclined holes according to various embodiments are shown. [Figure 4A] Exemplary ion traps having holes with a rectangular cross-section according to various embodiments are shown. [Figure 4B] Exemplary ion traps having holes with a rectangular cross-section according to various embodiments are shown. [Figure 4C] Exemplary ion traps having holes with a rectangular cross-section according to various embodiments are shown. [Figure 5A] Exemplary ion traps having spiral holes according to various embodiments are shown. [Figure 5B] Exemplary ion traps having spiral holes according to various embodiments are shown. [Figure 5C] Exemplary ion traps having spiral holes according to various embodiments are shown. [Figure 6] It is a process diagram of an exemplary embodiment of the present disclosure.

Mode for Carrying Out the Invention

[0022] While certain embodiments and examples are disclosed below, it will be understood by those skilled in the art that the scope of the invention may extend beyond the specifically disclosed embodiments and / or uses of the invention, as well as obvious modifications and equivalents thereof. Therefore, the scope of the invention disclosed is not intended to be limited by the specific disclosed embodiments described below.

[0023] The figures presented herein are not intended to represent the actual appearance of any particular material, apparatus, structure, or device, but are merely representations used to describe embodiments of the present disclosure.

[0024] As used herein, the term “substrate” may mean one or more of any substrate materials, for example, one or more of any substrate materials that can be modified or on which a device, circuit, or film can be formed.

[0025] As used herein, the term “atomic layer deposition (ALD)” may refer to a deposition process in which a deposition cycle, preferably a series of consecutive deposition cycles, is carried out in a process chamber. Typically, during each cycle, a precursor is chemisorbed onto the deposition surface (e.g., the surface of a substrate or a previously deposited underlayment, e.g., a material deposited using a previous ALD cycle) to form a monolayer or sub-monolayer that does not readily react with additional precursors (e.g., a self-controlled reaction). Subsequently, a reactant (e.g., another precursor or reaction gas) may be introduced into the process chamber for use in converting the chemisorbed precursor into the desired material on the deposition surface, as needed. Typically, this reactant can further react with the precursor. Furthermore, a purging step may also be utilized during each cycle to remove excess precursor from the process chamber and / or excess reactant and / or reaction byproducts after the conversion of the chemisorbed precursor. Furthermore, as used herein, the term “atomic layer deposition” also means to include related terms, such as “chemical vapor atomic layer deposition,” “atomic layer epitaxy (ALE),” “molecular beam epitaxy (MBE),” “gas source MBE,” or “organometallic MBE,” as well as processes specified by chemical beam epitaxy when carried out with alternating pulses of a precursor composition(s), reactive gas, and purge (e.g., inert carrier) gas.

[0026] As used herein, the term "Chemical Vapor Deposition (CVD)" may refer to any process in which a substrate is exposed to one or more volatile precursors, which react and / or decompose on the substrate surface to produce a desired deposit.

[0027] As used herein, the terms “film” and “thin film” may refer to any continuous or discontinuous structure and material deposited by the methods disclosed herein. For example, “film” and “thin film” may include 2D (Two Dimensions) materials, nanorods, nanotubes or nanoparticles, or even partial or complete molecular layers, partial or complete atomic layers, or clusters of atoms and / or molecules. “Film” and “thin film” may include materials or layers having pinholes, but may still be at least partially continuous.

[0028] As used herein, “chemisorption” may refer to an adsorption process caused by a reaction on an exposed surface that creates a covalent or ionic bond between the surface and the adsorbent.

[0029] As used herein, “gas” may refer to a state of matter consisting of atoms or molecules that have no defined volume or shape. Gases may include vaporized solids and / or liquids and may consist of a single gas or a mixture of gases, depending on the context.

[0030] As used herein, “plasma” may refer to an ionized gas containing approximately equal numbers of negatively and positively charged species, generally electrons and ions. Excited and reactive species may also be present in the plasma, such as atoms and radicals, metastable atoms and molecules, and photons. Plasma discharge requires an externally applied electric or magnetic field to ionize the gas. Plasma generation schemes and geometric shapes may include, but are not limited to, capacitively coupled plasma (CCP), inductively coupled plasma (ICP), and RF-hollow cathode (HC) plasmas, which differ in their generation of excited and reactive species and, as a result, can provide very different fluxes of various species.

[0031] As used herein, “precursor” may also mean a compound that participates in a chemical reaction to form another compound or element, and a portion of the precursor (an element or group within the precursor) may be incorporated into the compound or element resulting from the chemical reaction. The compound or element resulting from the chemical reaction may be a layer and / or film formed on the surface of a substrate.

[0032] As used herein, “reactant” refers to a compound that participates in a chemical reaction to form another compound or element. In some cases, the reactant may be a precursor. In other cases, the compound or element resulting from a chemical reaction does not contain any part of the reactant (an element or group within the reactant), and therefore the reactant is not a precursor.

[0033] All numerical ranges described throughout this disclosure may include upper and lower limits, and it should be understood that any narrower numerical ranges included within such broad numerical ranges are also deemed to be as if they were all explicitly described herein. For example, the phrases “about 2 to about 4” or “2 to 4” include 2 and 4, and the integers and / or integers are in the range of about 2 to about 3, about 3 to about 4, and each possible range is based on real numbers (e.g., irrational and / or rational), such as about 2.1 to about 3.9, about 2.1 to about 3.4, etc.

[0034] This disclosure generally relates to systems for forming films on the surface of a substrate using plasma-enhanced atomic layer deposition (PE-ALD), remote PE-ALD, and / or radical-enhanced ALD (RE-ALD), and in particular to the use of plasma to influence the partial decomposition of chemical precursors and improve their reactivity.

[0035] Reactor systems used in ALD, CVD, PE-ALD, remote PE-ALD, RE-ALD, and / or similar processes can be used for a variety of applications, including material deposition and etching on substrate surfaces. Figure 1 shows an exemplary reactor system 150 in which plasma can be formed above the reaction chamber 100, such as in the plasma zone 108. A first vapor-phase or gas-phase precursor may be supplied from a first precursor source 102, a second gas-phase precursor from a second precursor source 103, a third gas-phase precursor from a third precursor source 104, and / or a fourth gas-phase precursor from a fourth precursor source 105. The gas-phase precursors from the first precursor source 102, the second precursor source 103, the third precursor source 104, and / or the fourth precursor source 105 can be supplied into the reaction chamber 100 through a manifold 101. The manifold 101 may include a first valve 115 for controlling the flow of a first gas-phase precursor from a first precursor source 102, a second valve 116 for controlling the flow of a second gas-phase precursor from a second precursor source 103, a third valve 117 for controlling the flow of a third gas-phase precursor from a third precursor source 104, and / or a fourth valve 118 for controlling the flow of a fourth gas-phase precursor from a fourth precursor source 105. The precursors may flow into the reaction chamber 100 through a precursor distribution system 107 which may be positioned directly above the susceptor 111 on which the substrate 110 (i.e., wafer, planar substrate) is placed. The first precursor may be vaporized and mixed into the carrier gas, or pulsed into the carrier gas. The reactor system 150 may also be configured to allow the introduction of reaction gases and other gases (e.g., other precursors or reaction gases, carriers, diluents, process gases, feed gases, carrier gases, and / or purge gases) into the reaction chamber through the precursor distribution system 107 or from other ports (not shown).

[0036] Unreacted gases and gaseous reaction byproducts can be discharged from the reaction chamber 100 through the exhaust line 112. The reaction chamber 100 may optionally be provided with a purge line and / or pump line connected to a vacuum pump so that the reaction chamber can be purged between various reaction cycles (not shown).

[0037] The RF power supply 113 may be electrically connected to the precursor distribution system 107, which is biased relative to the susceptor 111, allowing a plasma discharge to form between the two. The applied bias allows ions and radicals to be accelerated downward toward the substrate 110 / susceptor 111. An ion trap 109 (e.g., a mesh plate) is positioned between the precursor distribution system 107 and the substrate 110 / susceptor 111 and may restrict the plasma zone 108 to the upper part of the reaction chamber 100 above the ion trap 109. The ion trap may be electrically grounded or connected to a grounding connection. In some embodiments, the ion trap may be a metal plate having one or more holes that allow radical species to pass through to the substrate 110 while trapping ions. The addition of the ion trap 109 can reduce or further eliminate electron-ion interactions with the surface of the substrate 110 by restricting the plasma to the plasma zone 108 at the top of the reaction chamber 100 and / or by the ion trap absorbing ions that attempt to flow toward the surface of the substrate 110.

[0038] The reactor system 150 may also include a controller 114 operably connected to a first gas valve 115, a second gas valve 116, a third gas valve 117, and a fourth gas valve 118, an RF power supply 113, and other components (not shown). The controller 114 may be configured and programmed to independently control (e.g., on and off) various gases (e.g., carrier gas, first precursor, reactive gas, and any diluents, process, feed, and / or purge gas) and the supply of the RF power supply 113 to deposit a film on the surface of the substrate 110, as needed. In some embodiments, the controller 114 may be configured to open valve 115 to allow the first gas phase precursor to flow from the first precursor source 102 into the reaction chamber 100. The controller 114 may further be configured to turn on the RF power supply 113 to form a plasma (e.g., a low-power plasma). Turning on the RF power supply 113 and opening valve 115 may be done sequentially or simultaneously. After a set period, the controller 114 may close valve 115 and turn off the RF power supply 113. Next, the controller 114 may open valve 116 to allow the second gas phase precursor to flow from the second precursor source 103 into the reaction chamber 100. After a set period, the controller 114 may close valve 116. The controller 114 may be programmed to repeat various process steps for growing a film on the surface of the substrate 110. The controller 114 may be programmed to perform other process steps between these various steps.

[0039] In another embodiment, the controller 114 may be configured to open valve 115 to allow a first precursor from a first precursor source 102 into the reaction chamber, and then open valve 116 to allow a second precursor from a second precursor source 103 into the reaction chamber, while the RF power supply 113 is turned on to form a plasma. Turning on the RF power supply 113 and opening valves 115 and 116 may be done sequentially or simultaneously. After a set period, the controller 114 may close valves 115 and 116 and turn off the RF power supply 113. Next, the controller 114 may open valve 117 to allow a third precursor from a third precursor source 104 into the reaction chamber 100, and after a set period, pulse the RF power supply 113 (on, then off). After another set period, the controller 114 may close valve 117. The controller 114 may be programmed to repeat various process steps for growing a film on the surface of the substrate 110. The controller 114 may be programmed to perform other process steps in between these various steps.

[0040] Figure 2A shows an exemplary ion trap 200 that may be provided within the reactor system 150. The ion trap 200 may have a number of pores 202. Although a limited number of pores are shown for the ion trap 200, the ion trap 200 may have hundreds or thousands of pores 202 in a showerhead-like pattern. The pores 202 may be cylindrical in shape, as shown in the outline of the exemplary pores 202 in Figure 2B. For example, the inner surface 214 of the pore 202 may be perpendicular (e.g., not inclined) to the top surface or bottom surface of the ion trap 200. The pores may have an upper opening 210A on the top surface of the ion trap 200 and / or a bottom opening 210B on the bottom surface of the ion trap 200. The upper opening 210A and the bottom opening 210B may be circular in shape with a diameter 206 of about 0.1 mm to about 5 mm. The height of pore 202 (and the thickness of ion trap 200) can range from approximately 5 mm to approximately 40 mm. Therefore, the aspect ratio of pore 202 can range from 1 to 400.

[0041] Figure 2C shows a cross-sectional view of the ion trap 200 along the x-x' axis. The pores 202 allow any radicals flowing toward the substrate (e.g., substrate 110) to pass through the ion trap 200 by enabling radicals to enter through the upper opening 210A on the top surface of the ion trap 200 and exit through the bottom opening 210B on the bottom surface of the ion trap. The pores 202 can capture some ions flowing toward the substrate. Typically, a high aspect ratio of the pores 202 of the ion trap 200, such as around 1 to 400, leads to effective capture or trapping of ions. However, the cylindrical shape of the pores 202 does not capture all ions, and some ions may be discharged through the bottom opening 210B on the bottom surface of the ion trap. For example, as shown in Figure 2C, ions 220 may flow towards the substrate in the vertical direction 212, enter the ion trap 200 through the upper opening 210A on the top surface of the ion trap 200, and be discharged through the bottom opening 210B on the bottom surface of the ion trap 200. Therefore, an ion trap 200 with cylindrical holes carries the risk of some ions coming into contact with the surface of the substrate, which could cause plasma-induced damage and anisotropy in the thin film formed on the surface of the substrate.

[0042] Another example of an ion trap 300 is shown in Figures 3A, 3B, and 3C, and the ion trap 300 may have higher efficiency in ion capture compared to the ion trap 200 in Figure 2A. The ion trap 300 may be installed within the reactor system 150 (for example, as ion trap 109). The ion trap 300 may have a plurality of inclined holes 302. Although a limited number of inclined holes are shown in the ion trap 300, the ion trap 300 may have hundreds or thousands of inclined holes 302. The inclined holes 302 may be oblique cylinders, as shown in the outline of an exemplary inclined hole 302 in Figure 3B. For example, the inner surface 314 of the hole 302 may be inclined (e.g., not perpendicular) with respect to the top surface or bottom surface of the ion trap 300. For example, the inner surface 314 of the inclined hole 302 may produce an angle 310 with respect to the top surface or bottom surface of the ion trap in the range of 45 to 89 degrees. In some embodiments, the angle 310 may be in the range of 70 to 85 degrees.

[0043] As shown in Figures 3B and 3C, the inclined hole 302 may have an upper opening 312A on the top surface of the ion trap 300 and / or a bottom opening 312B on the bottom surface of the ion trap 300. The upper opening 312A and the bottom opening 312B may be circular in shape with a diameter 306 of about 0.1 mm to about 5 mm. Alternatively, in other embodiments, the upper opening 312A and / or the bottom opening 312B may include a square shape, a rectangular shape, a parallelogram shape, or any two-dimensional shape. The height 308 of the inclined hole 302 may be 5 mm to about 40 mm. Thus, the aspect ratio of the inclined hole 302 (e.g., height 308 divided by diameter 306) may be 1 to 400. The height 308 of the inclined hole 302 may be greater than the thickness of the ion trap 300.

[0044] The ion traps 200 in Figures 2A to 2C may be formed by drilling holes perpendicular to the top or bottom surface of the ion trap 200, and the ion traps 300 in Figures 3A to 3C are formed by drilling holes at an angle (e.g., angle 310) to the top or bottom surface of the ion trap, resulting in inclined holes 302. Aside from the different hole designs of the ion traps, there may be no other changes to the reactor system 150 and / or the method of operating the reactor system 150 to process the substrate.

[0045] Figure 3C shows a cross-sectional view of the ion trap 300 along the x-x' axis. The inclined holes 302 allow any radical species flowing toward the substrate (e.g., substrate 110) to pass through the ion trap 300 by allowing radicals to enter through the upper opening 312A on the top surface of the ion trap 300 and exit through the bottom opening 312B on the bottom surface of the ion trap 300. However, the inclined inner surface 314 can trap ions flowing toward the substrate. For example, as shown in Figure 3C, ions 316 may flow toward the substrate in the vertical direction 318 and enter the ion trap 300 through the upper opening 312A on the top surface of the ion trap 300. After entering the inclined holes 302, ions 316 may collide with and / or be absorbed by the inclined inner surface 314.

[0046] The ion trap 300, having inclined pores 302, offers improved ion capture compared to the ion trap 200, potentially enabling complete removal of ions from the plasma flux and ensuring that only reactive radicals can reach the substrate. Therefore, the ion trap 300 with inclined pores 302 can enhance the REALD process by reducing the risk of unintended etching, densification, or anisotropic effects resulting from ion bombardment on the surface of the substrate 110.

[0047] Ion traps 200 having non-inclined pores 202 and / or ion traps 300 having inclined pores 302 may not allow sufficient radicals to pass through for efficient REALD processing. This may be because ion trap 200 may have hundreds or thousands of non-inclined pores 202 with a high aspect ratio (e.g., an aspect ratio greater than 10), and / or ion trap 300 may have hundreds or thousands of inclined pores 302 with a high aspect ratio (e.g., an aspect ratio greater than 10). Such pores with a high aspect ratio have a large internal area (e.g., the sum of the internal areas 214 of all pores 202, or the sum of the internal areas 314 of the inclined pores 302), which may hinder the delivery of radicals to the substrate because the large internal area may provide a larger surface area from which radicals can react or recombine with other radicals, ions, etc. This may reduce the flow rate of radicals through the ion trap.

[0048] The internal area of ​​an ion trap can be reduced by enlarging the pores. For example, Figure 4A shows an exemplary ion trap 400 having elongated pores 402 (e.g., slits within the ion trap 400). The cross-section of the elongated pores 402 may be a rectangle with 90-degree angles. Alternatively, the cross-section of the elongated pores 402 may be a rectangle with rounded angles, a trapezoid, or other similar two-dimensional shape. The lengths of the elongated pores 402 (e.g., lengths along the y-y' axes) may be parallel to each other and may extend from one edge of the ion trap 400 to the other end of the ion trap 400.

[0049] The elongated holes 402 may be non-inclined or inclined. For example, Figure 4B shows a cross-sectional view of an ion trap 400 having non-inclined elongated holes 402A, 402B, and 402C along the x-x' axis. The inner surface 414 of the non-inclined elongated holes 402A-402C may be perpendicular to the top surface or bottom surface of the ion trap 400. The angle 406 between the inner surface 414 and the top or bottom surface may be 90 degrees. Each of the non-inclined elongated holes 402A-402C may have an upper opening 422A on the top surface of the ion trap 400 and / or a bottom opening 422B on the bottom surface of the ion trap 400. The width 418 of the non-inclined elongated holes 402A-402C may be about 0.1 mm to 5 mm. The height 420 of the non-inclined elongated holes 402A-402C may be 5 mm to about 40 mm. The sum of the internal areas 414 of the elongated holes 402 may be less than the sum of the internal areas 214 of all the holes 202, or the sum of the internal areas 314 of the inclined holes 302.

[0050] The non-inclined elongated pores 402A-402C, like pore 202 of the ion trap 200, do not capture all ions, and some ions may be discharged through the bottom opening 422B on the bottom surface of the ion trap 400. Therefore, an ion trap 400 having inclined elongated pores 402D, 402E, 402F may be preferred, as illustrated in Figure 4C. The inclined elongated pores 402D-402F may have higher efficiency in ion capture compared to the non-inclined elongated pores 402A-402C in Figure 4B. Returning to Figure 4C, the inner surfaces 424 of the inclined elongated pores 402D-402F may be inclined (e.g., not perpendicular) with respect to the top surface or bottom surface of the ion trap 400. For example, the inner surface 424 of the inclined elongated holes 402D-402F may create an angle 404 in the range of 45-89 degrees with the top or bottom surface of the ion trap 400. In some embodiments, the angle 404 may be in the range of 70-85 degrees.

[0051] Each of the inclined elongated holes 402D to 402F may have an upper opening 432A on the upper surface of the ion trap 400 and / or a bottom opening 432B on the bottom surface of the ion trap 400. The width 428 of the upper opening 432A and the bottom opening 432B may be about 0.1 mm to about 5 mm. The inclination height 430 of the inclined elongated holes 402D to 402F may be 5 mm to about 40 mm.

[0052] The inclined elongated pores 402D-402F allow any radical species flowing toward the substrate (e.g., substrate 110) to pass through the ion trap 400 by allowing radicals to enter through the upper opening 432A on the top surface of the ion trap 400 and exit through the bottom opening 432B on the bottom surface of the ion trap 400. However, the inclined inner surface 424 can trap ions flowing toward the substrate because ions can collide with and / or be absorbed by the inclined inner surface 424. The sum of the inner areas 424 of the inclined elongated pores 402D-402F is smaller than the sum of all the inner areas 214 of the pores 202 or the sum of the inner areas 314 of the inclined pores 302. Therefore, the inclined elongated pores 402D-402F can reduce radical recombination inside the inclined elongated pores 402D-402F.

[0053] Figure 5A shows another exemplary ion trap 500 having a spiral (e.g., the white portion in the black ion trap) elongated pore 502. The spiral elongated pore 502 may or may not be inclined. For example, Figure 5B shows a cross-sectional view of an ion trap 500 having a non-inclined spiral elongated pore with portions 502A, 502B, 502C, and 502D along the x-x' axis. The inner surface 514 of portions 502A to 502D may be perpendicular to the top or bottom surface of the ion trap 500. The angles 504A and 504B between the inner surface 514 and the top or bottom surface may be 90 degrees. Each of portions 502A to 502D may have an upper opening 522A on the top surface of the ion trap 500 and / or a bottom opening 522B on the bottom surface of the ion trap 500. The width 518 of sections 502A to 502D may be approximately 0.1 mm to 5 mm. The height 520 of sections 502A to 502D may be 5 mm to approximately 40 mm. The total internal area 514 of the non-inclined spiral elongated holes may be less than the sum of all internal areas 214 of the holes 202, or the sum of the internal areas 314 of the inclined holes 302.

[0054] Similar to the holes 202 of the ion trap 200, non-inclined helical elongations do not capture all ions, and some ions may be discharged through the bottom opening 522B on the bottom surface of the ion trap 500. Therefore, an ion trap 500 having inclined helical elongations may be preferred. For example, Figure 5C shows a cross-sectional view of an ion trap 500 having inclined helical elongations with portions 502E, 502F, 502G, and 502H along the x-x' axis. Portions 502E-502H may have higher efficiency in ion capture compared to portions 502A-502D in Figure 5B. Returning to Figure 5C, the inner surfaces 524 of portions 502E-502H may be inclined (e.g., not perpendicular) with respect to the top surface or bottom surface of the ion trap 500. For example, the inner surface 524 of portions 502E to 502H may produce angles 504C and 504D with respect to the top or bottom surface of the ion trap in the range of 45 to 89 degrees. In some embodiments, angles 504C and 504D may be in the range of 70 to 85 degrees with respect to the top or bottom surface of the ion trap.

[0055] Each of sections 502E to 502H may have an upper opening 532A on the upper surface of the ion trap 500 and / or a bottom opening 532B on the bottom surface of the ion trap 500. The width 528 of sections 502E to 502H may be about 0.1 mm to about 5 mm. The inclination height 530 of the inclined spiral elongated hole may be 5 mm to about 40 mm.

[0056] Sections 502E-502H allow any radical species flowing toward the substrate (e.g., substrate 110) to pass through the ion trap 500 by enabling radicals to enter through the upper opening 532A on the top surface of the ion trap 500 and exit through the bottom opening 532B on the bottom surface of the ion trap 500. However, the inclined inner surface 524 can trap ions flowing toward the substrate because ions can collide with and / or be absorbed by the inclined inner surface 524. The total inner area 524 of the inclined helical elongated pores may be less than the total inner area 214 of all the pores 202 or the total inner area 314 of the inclined pores 302, and therefore having an ion trap 500 with inclined helical elongated pores can result in less radical recombination than an ion trap 500 with non-inclined helical elongated pores.

[0057] One aspect of the present disclosure is a method for depositing a film on the surface of a substrate contained in a reaction chamber using RE-ALD. Figure 6 is a process flow diagram of an embodiment of the present disclosure. The RE-ALD process may include a deposition process in which a deposition cycle, typically a number of consecutive deposition cycles, are carried out in a reactor system. Generally, in the RE-ALD process, during each cycle, a precursor and plasma are introduced into the reaction chamber to form radicals that can be chemisorbed onto the deposition surface (e.g., the substrate surface, which may include material already deposited by a previous RE-ALD cycle or other materials), forming a monolayer or sub-monolayer of material that does not readily react with additional radicals (i.e., a self-controlled reaction). Subsequently, reactants (e.g., another precursor with plasma or simply other precursors) may be introduced into the process chamber for use in converting the chemisorbed precursor into the desired material on the deposition surface. Between one or more cycles, for example between each step of each cycle, a purging step may be used to remove excess precursor from the process chamber and / or excess reactants, radicals and / or reaction byproducts from the reaction chamber. As used herein, the term “pulse” may refer to a procedure in which a reactive precursor or reactant is supplied to a reaction chamber, for example, between two purges, between a purge and another pulse, or between two pulses. It will be understood that pulses can be achieved either in time or space, or both. As used herein, the term “purge” may refer to a procedure in which an inert gas or substantially inert gas is supplied to a reaction chamber between two pulses of gases that react with each other. For example, a purge, for example, a purge using a noble gas, may be provided between a precursor pulse and a reactant pulse, thus avoiding, or at least minimizing, gas-phase interaction between the precursor and the reactant. Naturally, purges can be achieved either in time or space, or both.

[0058] Referring again to Figure 6, in step 610, the substrate (e.g., substrate 110) may be placed in the reaction chamber (e.g., reaction chamber 100) of the reactor system (e.g., reactor system 150). The substrate may be supported by a susceptor (e.g., susceptor 111). In step 620, an ion trap (e.g., ion trap 109) may be placed in the reaction chamber. The ion trap may be an ion trap 300 having inclined holes 302, an ion trap 400 having non-inclined elongated holes 402A-402C or inclined elongated holes 402D-402F, or an ion trap 500 having non-inclined helical holes (e.g., portions 502A-502D) or inclined helical holes (e.g., portions 502E-502H). The ion trap may be positioned above the substrate and below the precursor distribution system (e.g., precursor distribution system 107). The ion trap may be connected to the ground connection.

[0059] Step 610 may be optional. In step 630, a bias may be applied between the reaction system's susceptor (e.g., susceptor 111) or ion trap (e.g., ion trap 109) and the reactor system's precursor distribution system. The bias allows ions and radicals to be accelerated downward toward the substrate or susceptor of the reactor system.

[0060] In step 640, a deposition cycle may be initiated that can supply one or more precursors (e.g., precursors from the first precursor source 102, the second precursor source 103, the third precursor source 104, and / or the fourth precursor source 105) into the reaction chamber. The precursors may flow through a precursor distribution system that may be positioned directly above the ion trap. Other gases (e.g., other precursor or reaction gases, carriers, diluents, process gases, feed gases, carrier gases, and / or purge gases) may also be supplied.

[0061] In step 650, a plasma source may be supplied to partially decompose at least a portion of the supplied precursor to form activated radicals and ions. In the method disclosed herein, the plasma may be formed between an ion trap and a precursor distribution system and may be used to partially decompose at least a portion of the supplied precursor in step 640 to generate radicals (e.g., a radicalized precursor) and ions. The radicals may be more reactive than the precursor from which they originate, and these more reactive radicals may increase the chemiadsorption rate on the substrate surface. In this context, the term “decomposition” refers to the process or effect of dissociating, fragmenting, or breaking down a chemical entity (in this case, the precursor) into fragments, while “partial decomposition” means that the precursor is destroyed, but at least a portion of the molecular structure of the precursor remains substantially intact in the resulting radicalized precursor. Additional or alternative configurations include “partial decomposition” meaning that the precursor is destroyed, but not to the extent that bimolecular and / or non-self-limiting adsorption occurs on the substrate surface, and rather the radicalized precursor chemiadsorbs onto the substrate surface via a self-limiting process. Plasma can be generated by vapor-phase ionization of a precursor using a radio frequency (RF) power supply (e.g., 13.56 MHz or 27 MHz) (e.g., RF power supply 113). Typically, the RF power for generating the plasma is maintained at approximately 300 W or less, typically approximately 200 W or less, or more typically approximately 100 W or less.

[0062] In step 660, the ion trap allows the radicals from step 650 to pass through the ion trap, but the ions may be blocked by passing through the ion trap. More efficient ion blocking can be achieved by using an ion trap with inclined pores (e.g., ion trap 300 having inclined pore 302, ion trap 400 having inclined elongated pores 402D-402F, or ion trap 500 having inclined helical pores (e.g., having portions 502E-502H)).

[0063] In step 670, the radicals from step 650 may come into contact with the substrate to form a thin film of the material on the substrate. The method of contacting the substrate with the radicals may constitute one deposition cycle. In some embodiments, the method of depositing a thin film on the substrate may include repeating the deposition cycle once or more times. For example, method 600 may proceed to a decision gate 680 that determines whether to continue or terminate method 600. The decision gate 680 may be determined based on the thickness of the deposited film; for example, if the film thickness is insufficient, method 600 may return to step 640, and the steps of supplying the precursor and supplying the plasma source may be repeated once or more times. Before returning to step 640, in some embodiments, the reaction chamber may be purged with one or more purge gases (e.g., inert gases). In other embodiments, purging may be skipped. Purging the reaction chamber may remove any excess precursor from the process chamber, as well as / or any excess reactants, radicals, ions, and / or reaction byproducts from the reaction chamber.

[0064] The method may be terminated once the film has been deposited to the desired thickness. The film may be subjected to additional processes to form a device structure. The various steps shown in Figure 6 may be repeated once or multiple times to grow a film of the desired thickness on the substrate surface. For example, in some embodiments, the method includes repeating steps 640, 650, 660, and 670 once or multiple times to form a film of the desired thickness on the substrate surface. The number of times the deposition cycle is repeated (e.g., each cycle including steps 640, 650, 660, and 670) may depend on the growth rate per cycle (GPC, growth per cycle) of the deposition material and the desired thickness of the film. The method according to this disclosure may be carried out by maintaining the substrate temperature at about 40°C to about 600°C.

[0065] While exemplary embodiments of this disclosure are described herein, it should be understood that this disclosure is not limited thereto. For example, reactor systems are described in relation to various specific configurations, but this disclosure is not necessarily limited to these embodiments. Various modifications, variations, and enhancements of the systems and methods described herein can be made without departing from the spirit and scope of this disclosure.

[0066] The configurations and / or approaches described herein are illustrative in nature, and it will be understood that these particular embodiments or examples should not be considered limiting, as numerous variations are possible. Specific routines or methods described herein may represent one or more of any number of processing strategies. Therefore, the various operations described herein may be performed in the order described, in other orders, or, in some cases, omitted.

[0067] The subject matter of this disclosure includes all novel and non-obvious combinations and partial combinations thereof of the various processes, systems, and configurations disclosed herein, as well as all of their equivalents, including other configurations, functions, operations, and / or characteristics.

Claims

1. A reaction chamber, A susceptor configured to support the substrate, A precursor distribution system is positioned above the susceptor and configured to supply one or more precursors into the reaction chamber. A radio frequency power supply configured to supply radio frequency power for generating ions and radicals from one or more precursors within the reaction chamber, An ion trap positioned between the susceptor and the precursor distribution system, and having at least one pore, wherein the at least one pore is It is inclined with respect to the upper or lower surface of the ion trap, A reaction chamber comprising an ion trap, including an inner surface, configured to prevent the ions from passing through the ion trap and coming into contact with the substrate.

2. The reaction chamber according to claim 1, wherein the inner surface is at an angle of 70 to 85 degrees with the upper or lower surface of the ion trap.

3. The at least one of the holes has an opening on the top or bottom surface of the ion trap, The reaction chamber according to claim 1, wherein the opening has a circular shape with a diameter in the range of 0.1 to 5 millimeters.

4. The reaction chamber according to claim 1, wherein at least one of the holes is formed as an oblique cylinder.

5. The reaction chamber according to claim 4, wherein the oblique cylinder has an aspect ratio in the range of 1 to 400.

6. The at least one of the holes has an opening on the top or bottom surface of the ion trap, The reaction chamber according to claim 1, wherein the opening includes a circular, square, rectangular, or parallelogram shape.

7. The at least one of the holes has an opening on the top or bottom surface of the ion trap, The reaction chamber according to claim 1, wherein the opening includes a rectangular shape having a width in the range of 0.1 to 5 millimeters.

8. The ion trap comprises a plurality of holes having an inner surface inclined with respect to the upper surface or the bottom surface of the ion trap, The reaction chamber according to claim 7, wherein the plurality of holes are parallel to each other.

9. The at least one of the holes has an opening on the top or bottom surface of the ion trap, The reaction chamber according to claim 1, wherein the opening includes a helical shape having a width in the range of 0.1 to 5 millimeters.

10. The reaction chamber according to claim 1, wherein the ion trap has a thickness in the range of 5 to 40 millimeters.

11. The reaction chamber according to claim 1, wherein the at least one pore is configured to allow the radical to pass through the ion trap.

12. With additional controllers, The radio frequency power supply is electrically connected to at least one of the susceptor and the precursor distribution system. The reaction chamber according to claim 1, wherein the controller is configured to activate the radio frequency power supply and apply a voltage bias to at least one of the susceptor and the precursor distribution system, thereby enabling the ions to move perpendicularly toward the susceptor.

13. The reaction chamber according to claim 1, wherein the ion trap is connected to the ground connection.

14. An ion trap in a reaction chamber, Equipped with multiple holes, Each of the inner surfaces of the plurality of holes is inclined with respect to the upper or lower surface of the ion trap. An ion trap in which the plurality of pores are configured to block ions from passing through the ion trap and to allow radicals to pass through the ion trap.

15. The ion trap according to claim 14, wherein the inner surface of each of the plurality of holes creates an angle between the upper surface or the bottom surface of the ion trap and the inner surface of each of the plurality of holes, in the range of 70 to 85 degrees.

16. The ion trap according to claim 14, wherein each of the plurality of holes includes a slanted cylindrical shape having a diameter in the range of 0.1 to 5 millimeters and an aspect ratio in the range of 1 to 400.

17. The ion trap according to claim 14, wherein each of the plurality of pores includes a rectangular shape having a width in the range of 0.1 to 5 millimeters.

18. The ion trap according to claim 17, wherein the plurality of holes are parallel to each other.

19. The ion trap according to claim 14, wherein the ion trap has a thickness in the range of 5 to 40 millimeters.

20. An ion trap in a reaction chamber, Holes including a spiral shape, The inner surface of the hole is inclined with respect to the upper or lower surface of the ion trap. An ion trap, wherein the holes are configured to block ions from passing through the ion trap and allow radicals to pass through the ion trap.

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