Diffuser, method for manufacturing same, and plasma-enhanced chemical vapor deposition apparatus

Abstract

The present invention relates to a diffuser used in a process chamber and, more specifically, to a diffuser used in a plasma-enhanced chemical vapor deposition apparatus, comprising: a diffuser body including a plurality of gas passages extending from an upper surface through to a lower surface; and a protective layer formed on a wall surface of the gas passage of the diffuser body, wherein the protective layer includes a first protective layer formed by anodizing the diffuser body, a second protective layer formed by repeating a cycle of generating a single-atom layer on the first protective layer, and a third protective layer formed by vapor deposition on the second protective layer.

Description

Diffuser, manufacturing method thereof, and plasma-enhanced chemical vapor deposition apparatus

[0001] The present invention relates to a diffuser, a method for manufacturing the same, and a plasma-enhanced chemical vapor deposition apparatus.

[0002] Typically, plasma-enhanced chemical vapor deposition (PECVD) is used to deposit thin films on substrates such as semiconductor substrates, solar cell substrates, flat panel display (FPD) substrates, and organic light-emitting display (OLED) substrates. PECVD is typically performed by introducing a process gas into a vacuum chamber with a substrate positioned on a susceptor. The process gas is activated into plasma by applying radio frequency (RF) current to the chamber from one or more RF sources connected to the chamber. The plasma reacts to form a layer of material on the surface of the substrate positioned on the susceptor. Therefore, process chamber components are exposed to extreme environments, including a highly reactive, high-energy plasma environment composed of ions, electrons, and reactive species, a highly corrosive chemical gas environment, and a high-temperature environment.

[0003] To prevent corrosion in these extreme environments, process chamber components use various electrolytes on the aluminum substrate to form an anodized aluminum oxide film. However, even with this anodized film, the service life of process chamber components is limited to less than six months. Equipment must be shut down every six months to replace process chamber components, resulting in significant costs for both replacement and equipment maintenance.

[0004] A major reason for the shortened service life of process chamber components is that the aluminum anodic oxide film is corroded and cracked by plasma during the process, generating contaminant particles, which then increase exponentially.

[0005] [Prior Art Literature]

[0006] [Patent Document]

[0007] (Patent Document 1) Patent Publication No. 10-2023-0124520

[0008] The present invention has been devised to solve the problems of the above-described prior art, and its purpose is to improve the durability of components for a process chamber, particularly a diffuser that is exposed close to a high-temperature plasma environment.

[0009] In order to achieve the above-described object, a diffuser according to the present invention comprises a diffuser body used in a process chamber, which includes a plurality of gas passages extending from an upper surface to a lower surface; and a protective layer formed on a wall surface of the gas passage of the diffuser body, wherein the protective layer includes a first protective layer formed by anodizing the diffuser body; a second protective layer formed by repeating a single-atomic layer generation cycle on the first protective layer; and a third protective layer formed by vapor deposition on the second protective layer.

[0010] Meanwhile, a plasma-enhanced chemical vapor deposition apparatus according to the present invention comprises: a chamber body; a susceptor disposed within the chamber body to support a semiconductor wafer; a diffuser body including a plurality of gas passages extending from an upper surface to a lower surface; and a protective layer formed on a wall surface of the gas passages of the diffuser body, the diffuser being disposed within the chamber body to face the susceptor, wherein the protective layer comprises: a first protective layer formed by anodizing the diffuser body; a second protective layer formed by repeating a single-atomic layer generation cycle on the first protective layer; and a third protective layer formed by vapor deposition on the second protective layer.

[0011] Meanwhile, a method for manufacturing a diffuser used in a plasma-enhanced chemical vapor deposition apparatus according to the present invention comprises the steps of: providing a diffuser body including a plurality of gas passages extending from an upper surface to a lower surface; and forming a protective layer on a wall surface of the gas passages of the diffuser body, wherein the step of forming the protective layer comprises: forming a first protective layer by anodizing the diffuser body; forming a second protective layer by repeating a single-atomic layer generation cycle on the first protective layer; and forming a third protective layer by vapor deposition on the second protective layer.

[0012] The present invention improves the durability of components for process chambers, particularly diffusers that are exposed in close proximity to high-temperature plasma environments.

[0013] FIG. 1 is a drawing illustrating a plasma enhanced chemical vapor deposition apparatus according to a preferred embodiment of the present invention.

[0014] FIG. 2 is a drawing showing a portion of a gas passage of a diffuser according to a preferred embodiment of the present invention.

[0015] FIG. 3a is a drawing showing a part provided with a first protective layer and a second protective layer according to a preferred embodiment of the present invention, and FIG. 3b is a drawing showing a part provided with a first protective layer, a second protective layer, and a third protective layer according to a preferred embodiment of the present invention.

[0016] FIG. 4 is a drawing showing high-temperature plasma formed at the bottom of a diffuser according to a preferred embodiment of the present invention.

[0017] Figures 5a to 5c are drawings showing the manufacturing sequence of a diffuser according to a preferred embodiment of the present invention.

[0018] FIG. 6 is a drawing showing a state in which a gas passage is blocked when a third protective layer is formed deep inside the gas passage without following a preferred embodiment of the present invention.

[0019] The following merely exemplifies the principles of the invention. Therefore, those skilled in the art will be able to implement the principles of the invention and invent various devices within the scope and spirit of the invention, even if not explicitly described or illustrated herein. Furthermore, all conditional terms and embodiments listed herein are expressly intended, in principle, to facilitate understanding of the invention's concepts and should be understood as being in no way limiting to the specifically listed embodiments and conditions.

[0020] The above-described purposes, features and advantages will become clearer through the following detailed description with reference to the attached drawings, so that a person having ordinary skill in the art to which the invention pertains can easily practice the technical idea of ​​the invention.

[0021] Embodiments described herein will be described with reference to cross-sectional and / or perspective views, which are ideal exemplary drawings of the present invention. The thicknesses of films and regions, etc., illustrated in these drawings are exaggerated for the purpose of effectively explaining the technical contents. The form of the exemplary drawings may be modified due to manufacturing techniques and / or tolerances. Therefore, embodiments of the present invention are not limited to the specific forms illustrated, but also include changes in form resulting from the manufacturing process. The technical terms used herein are used only to describe specific embodiments and are not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this specification, it should be understood that the terms "comprises" or "includes" indicate the presence of a feature, number, step, operation, component, part, or combination thereof described in this specification, but do not preclude the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0022] Hereinafter, a preferred embodiment of the present invention will be described with reference to the drawings.

[0023] FIG. 1 is a drawing illustrating a plasma-enhanced chemical vapor deposition apparatus according to a preferred embodiment of the present invention, FIG. 2 is a drawing illustrating a part of a gas passage of a diffuser according to a preferred embodiment of the present invention, FIG. 3a is a drawing illustrating a part provided with a first protective layer and a second protective layer according to a preferred embodiment of the present invention, FIG. 3b is a drawing illustrating a part provided with a first protective layer, a second protective layer, and a third protective layer according to a preferred embodiment of the present invention, FIG. 4 is a drawing illustrating high-temperature plasma formed at the bottom of a diffuser according to a preferred embodiment of the present invention, FIGS. 5a to 5c are drawings illustrating a manufacturing sequence of a diffuser according to a preferred embodiment of the present invention, and FIG. 6 is a drawing illustrating a state in which a gas passage is blocked when the third protective layer is formed deep inside the gas passage without following the preferred embodiment of the present invention.

[0024] FIG. 1 is a drawing illustrating a plasma chemical vapor deposition apparatus (100) according to a preferred embodiment of the present invention.

[0025] The plasma chemical vapor deposition apparatus (100) includes a chamber body (102) having walls (110) defining a process space (180) and a bottom (111). Ports and / or valves (106) are provided to facilitate movement of a substrate (140) into and out of the chamber body (102). The plasma chemical vapor deposition apparatus (100) has a gas inlet manifold (114) composed of a cover plate (116), a backing plate (128), and a diffuser (120). A vacuum pump (129) is disposed at the bottom of the chamber body (102) to maintain the interior of the chamber body within a desired pressure range.

[0026] The diffuser (120) has a plurality of gas passages (11) for process gas or gases from a gas source (105) connected to the chamber body (102).

[0027] A diffuser (120) is positioned above the substrate and is vertically suspended by a support (115). Process gases are supplied through a gas block (117) mounted on the support (115). The gas block (117) is connected to the diffuser (120) through an aperture (119) in the support (115) and supplies the process gases to a plurality of gas passages (11) in the diffuser (120). In one embodiment, one or more process gases move through the gas block (117), the vertical aperture (119), and the inclined aperture (119a), and move into a space created between the backing plate (128) and the diffuser (120), and then the one or more process gases move through the plurality of gas passages (11) in the diffuser (120) and move into a process space (180) below the diffuser (120). The plasma generated from the plasma source (124) excites a gas or gases to deposit a film on the substrate.

[0028] The susceptor (112) is placed on the bottom of the chamber body (102). The susceptor (112) is grounded so as to be able to excite gases, source compounds, and precursors present in the process space (180).

[0029] RF power is applied to the diffuser (120) to generate an electric field within the process space (180).

[0030] The susceptor (112) includes one or more electrodes and / or heating elements (198) used to control the temperature of the susceptor (112) during the process. The heating elements (198) controllably heat the susceptor (112) and the substrate (140) positioned thereon to a set temperature within a determined temperature range, for example, greater than about 100 degrees Celsius.

[0031] The diffuser (120) is placed inside the chamber body (102) facing the susceptor (112).

[0032] Figure 2 is a drawing showing a cross-sectional view of a gas passage (11) according to a preferred embodiment of the present invention.

[0033] A diffuser (120) used in a process chamber includes a diffuser body (10) including a plurality of gas passages (11) extending from the upper surface to the lower surface, and a protective layer (20) formed on the wall surface of the gas passages (11) of the diffuser body (10). Here, the lower surface of the diffuser body (10) is a surface facing the susceptor (112), and the upper surface of the diffuser body (10) means a surface opposite the lower surface.

[0034] The protective layer (20) includes a first protective layer (21), a second protective layer (22) formed on the first protective layer (21), and a third protective layer (23) formed on the second protective layer (22).

[0035] The protective layer (20) includes a first protective layer (21) formed by anodizing the diffuser body (10); a second protective layer (22) formed by repeating a single-atomic layer generation cycle on the first protective layer (21); and a third protective layer (23) formed by vapor deposition on the second protective layer (22).

[0036] The first protective layer (21) to the third protective layer (23) have different formation mechanisms. As the protective layer (20) is formed in multiple layers by different formation mechanisms, the diffuser body (10) can be more effectively protected from a high-temperature plasma environment.

[0037] A method for manufacturing a diffuser used in a process chamber comprises the steps of: providing a diffuser body (10) including a plurality of gas passages (11) extending from an upper surface to a lower surface; forming a protective layer (20) on a wall surface of the gas passages (11) of the diffuser body (10), wherein the step of forming the protective layer (20) comprises: forming a first protective layer (21) by anodizing the diffuser body (10); forming a second protective layer (22) by repeating a single-atomic layer generation cycle on the first protective layer (21); and forming a third protective layer (23) by vapor deposition on the second protective layer (22).

[0038] First, a step of preparing a diffuser body (10) including a plurality of gas passages (11) extending from the upper surface to the lower surface is performed. The diffuser body (10) may be made of aluminum or an aluminum alloy material, and the gas passages (11) may be formed by a processing method.

[0039] Next, as illustrated in Fig. 5a, a step of forming a first protective layer (21) by anodizing the diffuser body (10) is performed. The first protective layer (21) is formed by anodizing the diffuser body (10). Accordingly, the first protective layer (21) is formed over the entire inner wall of the gas passage (11).

[0040] Next, as illustrated in Fig. 5b, a step of forming a second protective layer (22) by repeating a single-atom layer generation cycle on the first protective layer (21) is performed. Accordingly, a second protective layer (222) is formed over the entire inner wall of the gas passage (11).

[0041] The second protective layer (22) is formed by repeatedly performing a single-atom layer generation cycle in which a precursor gas adsorption step, an inert gas supply step, a reactant gas adsorption step and a substitution step, and an inert gas supply step are sequentially performed.

[0042] The second protective layer (22) can be formed by alternately supplying precursor gas and reactant gas. In this case, the second protective layer (22) can be formed with a different composition depending on the composition of the precursor gas and reactant gas.

[0043] As an example, the second protective layer (22) can be formed by alternately supplying a precursor gas of at least one of aluminum, silicon, hafnium, zirconium, yttrium, erbium, titanium, and tantalum and a reactant gas capable of forming the second protective layer (22).

[0044] The second protective layer (22) formed by alternately supplying precursor gas and reactant gas may include at least one of an aluminum oxide layer, an yttrium oxide layer, a hafnium oxide layer, a silicon oxide layer, an erbium oxide layer, a zirconium oxide layer, a fluoride layer, a transition metal layer, a titanium nitride layer, a tantalum nitride layer, and a zirconium nitride layer, depending on the composition of the precursor gas and the reactant gas.

[0045] The second protective layer (22) can be formed with a different composition depending on the composition of the precursor gas and reactant gas used. The material forming the second protective layer (22) may be amorphous. This can more effectively block the penetration of corrosive gases.

[0046] The second protective layer (22) can be formed by repeatedly performing a cycle of adsorbing a precursor gas on top of the first protective layer (21), supplying a reactant gas, and generating a monoatomic layer through chemical substitution of the precursor gas and the reactant gas (hereinafter referred to as a “monoatomic layer generation cycle”).

[0047] When a cycle of generating a single atomic layer is performed, a single thin layer of atomic layer can be formed on the upper side of the first protective layer (21). By repeatedly performing the cycle of generating a single atomic layer, multiple layers of atomic layers can be formed. More specifically, the second protective layer (22) can be manufactured by repeatedly performing a cycle of generating a single atomic layer in which a precursor gas adsorption step of adsorbing a precursor gas on the surface, a carrier gas supply step, a reactant gas adsorption and replacement step, and a carrier gas supply step are sequentially performed to generate multiple layers of atomic layers.

[0048] In the precursor gas adsorption step, a process of forming a precursor adsorption layer by supplying a precursor gas to the surface using a precursor gas supply unit and adsorbing it can be performed. The precursor adsorption layer is formed into only one layer by a self-limiting reaction. Then, a carrier gas supply step can be performed using a carrier gas supply unit. In the carrier gas supply step, a process of removing excess precursor from the precursor adsorption layer is performed by supplying a carrier gas. In this case, an exhaust system can operate simultaneously. The carrier gas can remove excess precursor remaining in the precursor adsorption layer, which has formed only one layer by a self-limiting reaction. Then, a reactant gas adsorption and replacement step can be performed using a reactant gas supply unit. In the reactant adsorption and replacement step, a process of supplying a reactant gas to the surface of the precursor adsorption layer to adsorb the reactant gas on the surface of the precursor adsorption layer and forming a monoatomic layer by chemical substitution of the precursor adsorption layer and the reactant gas can be performed. Then, a process of removing excess reactant gas is performed by performing a carrier gas supply step.

[0049] A step of repeatedly performing a single-atomic layer generation cycle to generate multiple single-atomic layers is performed, through which a second protective layer (22) can be formed. This second protective layer (22) provides improved corrosion resistance against a high-temperature plasma environment.

[0050] As illustrated in Fig. 5c, a step of forming a third protective layer (23) by vapor deposition on the second protective layer (22) is performed. The third protective layer (23) is formed by vapor deposition. Preferably, it is formed using a chemical vapor deposition method (CVD). Accordingly, the third protective layer (23) is formed on a portion of the lower portion of the gas passage (11).

[0051] The second protective layer (22) may be formed of an aluminum oxide layer (Al2O3) or an yttrium oxide layer (Y2O3). To improve compatibility with the first protective layer (21), it may be formed of the same material as the first protective layer (21). For example, when the first protective layer (21) is formed of an aluminum oxide layer (Al2O3), the second protective layer (22) is also formed of an aluminum oxide layer (Al2O3).

[0052] The third protective layer (23) may be formed of an aluminum oxide layer (Al2O3) or an yttrium oxide layer (Y2O3). In order to improve compatibility with the second protective layer (22), it may be formed of the same material as the second protective layer (22). For example, when the second protective layer (22) is formed of an aluminum oxide layer (Al2O3), the third protective layer (22) is also formed of an aluminum oxide layer (Al2O3). When the second protective layer (22) is formed of an yttrium oxide layer (Y2O3), the third protective layer (23) is also formed of an yttrium oxide layer (Y2O3). Meanwhile, in order to reduce the manufacturing cost of the second and third protective layers (22, 23), the second and third protective layers (22, 23) may be formed of an aluminum oxide layer (Al2O3).

[0053] The thickness of the first protective layer (21) is in the range of 100 nm to 1000 nm. More preferably, it may have a range of 300 nm to 400 nm. The thickness of the second protective layer (22) is in the range of 100 nm to 1000 nm. More preferably, it may have a range of 300 nm to 400 nm. The thickness of the third protective layer (22) is in the range of 100 nm to 1000 nm. More preferably, it may have a range of 300 nm to 400 nm. Therefore, the overall thickness of the first to third protective layers (21, 22, 23) is in the range of 300 nm to 3000 nm, and preferably, it may have a range of 1000 nm to 1200 nm.

[0054] Since the lower surface of the diffuser (120) is exposed to a more extreme environment than the upper surface of the diffuser (120) due to the high-temperature plasma environment, the lower surface of the diffuser body (10) is provided with a third protective layer (23). In addition, the inner wall of a lower portion of the gas passage (11) that is continuous with the lower surface of the diffuser body (10) also has a third protective layer (23). Therefore, as illustrated in FIG. 2, the first protective layer (21) and the second protective layer (22) are provided on the entire gas passage (11), while the third protective layer (23) is provided on a lower portion of the gas passage (11).

[0055] FIG. 3a is a drawing showing a part provided with a first protective layer (21) and a second protective layer (22) according to a preferred embodiment of the present invention, and FIG. 3b is a drawing showing a part provided with a first protective layer (21), a second protective layer (22), and a third protective layer (23) according to a preferred embodiment of the present invention.

[0056] The diffuser body (10) includes a plurality of gas passages (11) extending from the upper surface to the lower surface. Each gas passage (11) includes a first part (1) communicating with the upper surface, a second part (2) communicating with the first part (1), a third part (3) communicating with the second part (2), and a fourth part (4) communicating with the third part (3) to facilitate spraying gas into the process space (180).

[0057] The first part (1) is a part that communicates with the upper surface of the diffuser body (10). The second part (2) is provided between the first part (1) and the third part (3) and is a part that has a minimum inner diameter. The third part (3) is provided between the second part (2) and the fourth part (4) and has a third-1 part (3a) and a third-2 part (3b). The third-1 part (3a) has a relatively smaller inner diameter than the third-2 part (3b). The fourth part (4) is a part that communicates with the third part and the lower surface of the diffuser body (10), and the inner diameter thereof increases toward the lower surface.

[0058] Based on the gas passage (11), the first protective layer (21) and the second protective layer (22) are provided in the first part (1), the second part (2), the third part (3), and the fourth part (4), whereas the third protective layer (23) is provided only in the fourth part (4).

[0059] The fourth part (4) is formed in a shape in which the inner diameter increases as it goes downward. In other words, the fourth part (4) is formed in a shape in which the inner diameter decreases as it goes toward the second part (2). The first protective layer (21) to the third protective layer (23) are formed by different formation mechanisms. Since the anodizing treatment for forming the first protective layer (21) and the single-atom layer generation cycle for forming the second protective layer (22) are formed conformally along the surface shape of the gas passage (11), it is preferable to provide them to all of the first to fourth parts (1, 2, 3, 4). However, since the third protective layer (23) is formed by chemical vapor deposition, when it is desired to form the third protective layer (23) beyond the fourth part (4) to the third part (3), the hole of the second part (2) can be blocked, as illustrated in FIG. 6.

[0060] Therefore, the deposition process must be precisely controlled so that the third protective layer (23) is deposited only on the fourth portion (4). Accordingly, as illustrated in Fig. 2, the deposition thickness of the third protective layer (23) formed on the fourth portion (4) decreases from the bottom to the top of the fourth portion (4).

[0061] The reason why the third protective layer (23) is formed by chemical vapor deposition is to form the third protective layer (23) only in the fourth part (4). If the third protective layer (23) is additionally formed on the second protective layer (22) by repeating the single-atomic layer generation cycle, the hole in the second part (2) can be blocked by the third protective layer (23). More specifically, in order to improve corrosion resistance against a plasma environment, the third protective layer (23) must be formed to a sufficient thickness. However, if the single-atomic layer generation cycle is repeated to form a sufficient thickness, the third protective layer (23) blocks the hole in the second part (2) or reduces the inner diameter of the hole, thereby hindering the flow of process gas.

[0062] Therefore, in order to improve corrosion resistance against a plasma environment without blocking the hole of the second part (2) or reducing the inner diameter of the hole of the second part (2), a third protective layer (23) is formed on a lower part of the gas passage (11) by chemical vapor deposition.

[0063] As a result, the second protective layer (22) formed on the first protective layer (21) improves the corrosion resistance of the first protective layer (21) against high temperature and corrosive gas environments, and the third protective layer (23) formed on the second protective layer (22) improves the corrosion resistance of the second protective layer (22) against high energy, highly reactive plasma environments. As a result, the durability of the diffuser (120) is improved.

[0064] Referring to Fig. 4, a high-energy, highly reactive plasma environment is created between the diffuser (120) and the substrate (w). The plasma environment has the greatest influence on the lower surface of the diffuser (120), and the first protective layer (21), the second protective layer (22), and the third protective layer (23) provided on the lower surface of the diffuser (120), and the first protective layer (21), the second protective layer (22), and the third protective layer (23) provided on the lower portion of the gas passage (11) improve corrosion resistance against the plasma environment. In addition, since the third protective layer (23) is formed only on the lower portion of the gas passage (11), the flow of process gas passing through the gas passage (11) is not obstructed.

[0065] As described above, the present invention has been described with reference to preferred embodiments thereof, but it will be apparent to those skilled in the art that various modifications or variations may be made to the present invention without departing from the spirit and scope of the present invention as set forth in the following claims.

[0066] [Explanation of symbols]

[0067] Gas passage: 11

[0068] Diffuser body: 10

[0069] Protective layer: 20

[0070] Diffuser: 120

Claims

1. For diffusers used in process chambers, A diffuser body including a plurality of gas passages extending from the upper surface to the lower surface; Including a protective layer formed on the wall surface of the gas passage of the above diffuser body, The above protective layer is, A first protective layer formed by anodizing the above diffuser body; A second protective layer formed by repeating a single-atom layer generation cycle on the first protective layer; and A diffuser used in a plasma-enhanced chemical vapor deposition apparatus, comprising a third protective layer formed by vapor deposition on the second protective layer.

2. Chamber body; A susceptor positioned within the chamber body to support a semiconductor wafer; A diffuser body including a plurality of gas passages extending from the upper surface to the lower surface, and a diffuser disposed within the chamber body facing the susceptor, including a protective layer formed on the wall surface of the gas passages of the diffuser body, The above protective layer is, A first protective layer formed by anodizing the above diffuser body; A second protective layer formed by repeating a single-atom layer generation cycle on the first protective layer; and A plasma-enhanced chemical vapor deposition apparatus comprising a third protective layer formed by vapor deposition on the second protective layer.

3. In the manufacturing method of a diffuser used in a process chamber, A step of providing a diffuser body including a plurality of gas passages extending from the upper surface to the lower surface; and Including a step of forming a protective layer on the wall surface of the gas passage of the above diffuser body, The step of forming the above protective layer is: A step of forming a first protective layer by anodizing the above diffuser body; A step of forming a second protective layer by repeating a single-atom layer generation cycle on the first protective layer; and A method for manufacturing a diffuser used in a plasma-enhanced chemical vapor deposition apparatus, comprising the step of forming a third protective layer by vapor deposition on the second protective layer.

Images