Plasma reaction apparatus, method for processing process gas by using same, and semiconductor process equipment having same

Abstract

A plasma reaction apparatus of an embodiment comprises: a main body; a plurality of dielectrics; a cell structure; and a plurality of high voltage electrodes. The main body is installed to be connected to a vacuum pipe and allows process gas to pass therethrough. The plurality of dielectrics are positioned inside the main body and are formed in tubular shapes. The cell structure is fixed to the inside of the main body so as to be grounded together with the main body, and partitions a plurality of unit cells respectively surrounding the plurality of dielectrics together with the main body. The plurality of high voltage electrodes are positioned inside the plurality of dielectrics, respectively, and receive a driving voltage applied from a power source to generate plasma in the plurality of unit cells. The cell structure includes a process gas inlet positioned at an upstream side of each of the plurality of unit cells and a process gas outlet positioned at a downstream side of each of the plurality of unit cells.

Description

Plasma reactor, process gas processing method using the same, and semiconductor process equipment equipped with the same

[0001] This invention relates to a plasma reactor, and more specifically, to a plasma reactor for decomposing, capturing, and cleaning process byproducts discharged from a process chamber.

[0002] Semiconductor manufacturing involves depositing thin films on wafers within a process chamber and selectively etching them repeatedly to create semiconductor chips with specific patterns. The process chamber is connected to a vacuum pump via a vacuum tube, evacuating the interior. During the process, various process byproducts are generated, including undecomposed greenhouse gases, undecomposed precursors, and particle byproducts.

[0003] As semiconductor processes become more refined, the amount of process byproducts emitted is increasing. Typically, these byproducts are decomposed and stabilized in a burner-type scrubber device located after a vacuum pump before being released into the atmosphere. However, burners decompose these byproducts at high temperatures while mixing them with nitrogen, the pump purge gas, resulting in the emission of large quantities of carbon oxides and nitrogen oxides, which pose an obstacle to the semiconductor industry's carbon neutrality.

[0004] Some of the process byproducts discharged from the process chamber accumulate in the vacuum tubes and vacuum pumps, shortening their lifespan and potentially causing safety hazards during tube and pump replacement. Conventionally, traps were installed in the vacuum tubes to physically capture the process byproducts, thereby reducing the amount of byproducts entering the vacuum pump. However, as the amount of process byproducts increases, the trap device's capture capacity is reaching its limits.

[0005] One aspect of the present disclosure is to provide a plasma reactor capable of efficiently decomposing and cleaning byproducts in process gases discharged from a process chamber, thereby extending the replacement cycle of vacuum tubes and vacuum pumps and maintaining vacuum in the vacuum tube even when the dielectric is damaged. Another aspect of the present disclosure is to provide a process gas processing method using the same, and a semiconductor process facility using the same.

[0006] According to one embodiment, a plasma reactor includes (i) a main body connected to a vacuum tube and through which a process gas passes, (ii) a plurality of tubular dielectrics positioned inside the main body, (iii) a cell structure fixed to the inside of the main body and grounded together with the main body, and defining a plurality of unit cells that surround each of the plurality of dielectrics together with the main body, and (iv) a plurality of high-voltage electrodes positioned inside each of the plurality of dielectrics and receiving a driving voltage from a power source to generate plasma in the plurality of unit cells. The cell structure has a process gas inlet positioned on an upstream side of each of the plurality of unit cells, and a process gas outlet positioned on a downstream side of each of the plurality of unit cells.

[0007] A plurality of unit cells may be positioned adjacent to each other, forming a plurality of rows and a plurality of layers. The cell structure may include a plurality of first plates orthogonal to a first direction, which is a flow direction of the process gas, and a plurality of second plates positioned parallel to the first direction between the plurality of first plates.

[0008] At least one of the plurality of dielectrics can be in contact with a downstream first plate among the plurality of first plates.

[0009] Multiple genomes can have different sizes per layer in multiple layers.

[0010] The plurality of dielectrics may be provided in different numbers per layer in the plurality of layers, and at least one of the plurality of dielectrics may have a different diameter from the other dielectrics.

[0011] Each of the plurality of dielectrics and the plurality of first plates positioned in one of the plurality of columns may be positioned at a different height along the first direction from the plurality of dielectrics and the plurality of first plates positioned in another column.

[0012] The body may include an upper plate, a lower plate, and a side wall. The side wall may include a basic side wall connected to the upper plate and the lower plate, and an extension portion extending outward from the basic side wall. The cell structure may define a plurality of unit cells together with the extension portion.

[0013] At least two genomes of different layers among the plurality of genomes can be positioned orthogonally to each other.

[0014] On the other hand, a plurality of unit cells may be positioned adjacent to each other to form a single layer. The cell structure may include a mesh plate and a first plate positioned orthogonal to a first direction, which is a flow direction of a process gas, with a plurality of dielectrics interposed therebetween, and a second plate positioned parallel to the first direction between the mesh plate and the first plate.

[0015] The body may include an upper plate, a lower plate, and side walls. A plurality of dielectrics may be arranged close to the lower plate and the side walls with a distance therebetween. The cell structure may include a first plate orthogonal to a first direction, which is a flow direction of the process gas, and a plurality of second plates parallel to the first direction, and may define a plurality of unit cells together with portions of the lower plate and the side walls.

[0016] The body may include a side wall having a plurality of through holes. Each of the plurality of dielectrics may be fitted into the through holes. Both ends of each of the plurality of high voltage electrodes may be connected to an insulating support via an O-ring.

[0017] At least one of the plurality of high voltage electrodes may be configured as a hollow tubular body and may accommodate cooling water in its internal space.

[0018] The vacuum tube may include an inlet vacuum tube connected to the inlet of the main body, and a plasma pretreatment unit for generating plasma of any one of capacitively coupled plasma (CCP), inductively coupled plasma (ICP), and transformer coupled plasma (TCP) may be installed in the inlet vacuum tube.

[0019] The body may include an upper plate, a lower plate, and side walls, and the cell structure and portions of the lower plate and side walls may define a plurality of trap sections.

[0020] A process gas treatment method using a plasma reactor according to one embodiment includes (i) a primary decomposition and capture step of generating plasma by applying a driving voltage to a high voltage electrode to decompose byproducts in a process gas into plasma and capturing the solid decomposition byproducts on the walls of a plurality of unit cells, and (ii) a secondary decomposition and gasification step of generating plasma by applying a driving voltage to a high voltage electrode simultaneously with supply of a cleaning gas and thereby gasifying the captured decomposition byproducts through plasma cleaning.

[0021] The primary decomposition and capture step may be performed during the deposition or etching step of the process chamber, and the re-decomposition step may be performed during the cleaning step of the process chamber.

[0022] A semiconductor process facility according to one embodiment includes (i) a process chamber in which either a deposition or an etching process is performed and a process gas is discharged, (ii) a vacuum pump connected to the process chamber via a vacuum tube and evacuating the interior of the process chamber, and (iii) a plasma reaction device having the above-described configuration, which is connected to the vacuum tube and decomposes and captures byproducts in the process gas by plasma, and redisassembles and gasifies the captured decomposition byproducts by plasma cleaning.

[0023] In the plasma reactor of the embodiments, vacuum leakage can be suppressed by an O-ring even when the dielectric is damaged, thereby maintaining a vacuum without additional devices such as a dual chamber. Furthermore, the plasma reactor of the embodiments can increase the surface area of ​​the dielectric in contact with the high-voltage electrode, thereby applying high power to the high-voltage electrode, and can enhance the decomposition and cleaning function by plasma.

[0024] Fig. 1 is a perspective view showing the external appearance of a plasma reaction device according to the first embodiment.

[0025] Fig. 2 is a cross-sectional view of a plasma reactor taken along line AA of Fig. 1.

[0026] Fig. 3 is a cross-sectional view of a plasma reactor taken along line BB of Fig. 1.

[0027] Figure 4 is a schematic diagram showing a unit cell of an embodiment and a unit cell of a comparative example.

[0028] Figure 5 is a cross-sectional view of a plasma reaction device according to the second embodiment.

[0029] Fig. 6 is a cross-sectional view of a plasma reaction device according to the third embodiment.

[0030] Fig. 7 is a cross-sectional view of a plasma reaction device according to the fourth embodiment.

[0031] Fig. 8 is a cross-sectional view of a plasma reaction device according to the fifth embodiment.

[0032] Fig. 9 is a cross-sectional view of a plasma reaction device according to the sixth embodiment.

[0033] Fig. 10 is a cross-sectional view of a plasma reaction device according to the seventh embodiment.

[0034] Fig. 11 is a perspective view showing the external appearance of a plasma reaction device according to the eighth embodiment.

[0035] Fig. 12 is a cross-sectional view of a plasma reactor taken along line CC of Fig. 11.

[0036] Fig. 13 is a cross-sectional view of a plasma reaction device according to the ninth embodiment.

[0037] Fig. 14 is a cross-sectional view of a plasma reaction device according to the 10th embodiment.

[0038] Fig. 15 is a cross-sectional view of a high-voltage electrode in a plasma reactor according to the 11th embodiment.

[0039] Fig. 16 is a cross-sectional view of a plasma reaction device according to the 12th embodiment.

[0040] Figure 17 is a schematic diagram showing various variations of the unit cell.

[0041] Figure 18 is a schematic diagram showing a first plate corresponding to one unit cell.

[0042] Figure 19 is a configuration diagram of a semiconductor processing facility equipped with a plasma reaction device according to one embodiment.

[0043] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the attached drawings so that those skilled in the art can easily implement the present disclosure. The present disclosure may be implemented in various different forms and is not limited to the embodiments described herein.

[0044] Fig. 1 is a perspective view showing the external appearance of a plasma reactor according to the first embodiment. Figs. 2 and 3 are cross-sectional views of the plasma reactor taken along lines AA and BB of Fig. 1, respectively.

[0045] Referring to FIGS. 1 to 3, the plasma reactor (100) of the first embodiment is installed connected to a vacuum tube (201, 202) that connects a process chamber and a vacuum pump, and is configured to decompose byproducts (undecomposed greenhouse gases, undecomposed precursors, particle byproducts, etc.) in a process gas discharged from the process chamber by plasma, capture the decomposition byproducts in a solid state, and redisassemble and gasify the captured decomposition byproducts by plasma cleaning.

[0046] Decomposition (primary decomposition) and capture by plasma can be carried out in the etching or deposition stage of the process chamber, and re-decomposition (secondary decomposition) and gasification by plasma cleaning can be carried out in the cleaning stage of the process chamber.

[0047] The plasma reactor (100) includes a main body (10) connected to a vacuum tube (201, 202). The main body (10) may have a width greater than the diameter of the vacuum tube (201, 202), and may be composed of an upper plate (11) and a lower plate (12) connected to the vacuum tube (201, 202), and a side wall (13) connecting the upper plate (11) and the lower plate (12). In the drawing, a main body (10) having a rectangular parallelepiped shape is illustrated, but the shape of the main body (10) is not limited to the illustrated example.

[0048] For convenience, the vacuum tube on the upstream side of the main body (10) is called an inlet vacuum tube (201), and the vacuum tube on the downstream side of the main body (10) is called an exhaust vacuum tube (202). The process gas flows into the inside of the main body (10) from the inlet vacuum tube (201), passes through the inside of the main body (10), and then is discharged through the exhaust vacuum tube (202). The flow direction of the process gas from the inlet vacuum tube (201) toward the exhaust vacuum tube (202) is called a first direction (D1), and the directions orthogonal to the first direction (D1) are called a second direction (D2) and a third direction (D3). The second direction (D2) and the third direction (D3) are orthogonal to each other. In this specification, the term "orthogonal" includes not only cases where the two intersect at exactly 90°, but also cases where there is a certain degree of error and the two intersect at approximately 90°.

[0049] Although the drawing illustrates a case where the flow direction of the process gas coincides with the direction of gravity (vertical direction), the flow direction of the process gas may also be a horizontal direction parallel to the ground. In this case, the inlet vacuum tube (201), the main body (10), and the discharge vacuum tube (202) illustrated in FIGS. 1 to 3 may be rotated 90° to be positioned parallel to the ground. Below, a case where the flow direction of the process gas coincides with the direction of gravity will be described as an example.

[0050] A plasma reactor (100) includes a plurality of dielectrics (20) positioned inside a main body (10), a high-voltage electrode (30) positioned inside each of the plurality of dielectrics (20), and a cell structure (50) that defines a plurality of unit cells (40) that surround each of the plurality of dielectrics (20) together with the main body (10). The plurality of unit cells (40) may be positioned adjacent to each other to form a plurality of rows and a plurality of layers.

[0051] The dielectric (20) may have a hollow cylindrical shape, and may be positioned such that the longitudinal direction is parallel to the third direction (D3). A plurality of dielectrics (20) having the same diameter and length may be positioned at a distance from each other along the first direction (D1) and the second direction (D2). In the drawing, a case in which six dielectrics (20) are arranged in two layers and three rows is illustrated, but the number and arrangement of the dielectrics (20) are not limited to the illustrated example.

[0052] The dielectric (20) limits the current rise and prevents the plasma from transitioning to arc mode. The dielectric (20) can be made of glass, quartz, alumina, or the like. Alternatively, the dielectric (20) can be made by performing ceramic coating, anodizing, or plating on the surface of the high-voltage electrode (30).

[0053] The high voltage electrode (30) may have a cylindrical shape and is in contact with the inner wall of the dielectric (20). Both ends of the dielectric (20) may be fixedly installed on the side wall (13), and both ends of the high voltage electrode (30) may be installed connected to the side wall (13) while being insulated from the side wall (13). For example, a through hole may be positioned in the side wall (13), and both ends of the dielectric (20) may be fitted into the through hole of the side wall (13).

[0054] And an insulating support (60) can be coupled to both ends of the high voltage electrode (30). The insulating support (60) has a diameter larger than the diameter of the through hole and can be fixedly installed on the outer surface of the side wall (13). The insulating support (60) insulates the high voltage electrode (30) and the side wall (13) and seals the through hole of the side wall (13).

[0055] A first O-ring (61) may be positioned between the end of the high voltage electrode (30) and the insulating support (60), and a second O-ring (62) may be positioned between the outer surface of the side wall (13) and the insulating support (60). The diameter of the second O-ring (62) is larger than that of the first O-ring (61). The first and second O-rings (61, 62) function to maintain a seal so that a vacuum does not leak when the dielectric (20) is damaged by an arc. The insulating support (60) may be made of an engineering plastic that is elastic and resistant to heat.

[0056] The high voltage electrode (30) may include a connection portion (31) connected to a power source. The connection portion (31) is located at least on one end of both ends of the high voltage electrode (30) and may extend outward from the insulating support (60) by penetrating the insulating support (60). The high voltage electrode (30) receives a driving voltage for plasma generation from the power source. The driving voltage may be a low frequency (AC) voltage or a high frequency (RF) voltage.

[0057] The cell structure (50) is fixed to the inside of the main body (10) and is grounded together with the main body (10), and can partition a plurality of unit cells (40) into multiple layers together with a portion of the side wall (13). The cell structure (50) partitioning the unit cells (40) and a portion of the side wall (13) can function as a ground electrode and, at the same time, as a collection plate that captures decomposition byproducts caused by plasma. Among the multi-layered unit cells (40), the layer close to the inlet vacuum tube (201) is conveniently referred to as the first layer, and the layer close to the exhaust vacuum tube (202) is referred to as the second layer.

[0058] The cell structure (50) may include a plurality of first plates (51, 52, 53) positioned on both sides (upper and lower sides based on the drawing) of a plurality of dielectrics (20) along a first direction (D1), and a plurality of second plates (54, 55) positioned on at least one side (left or right side based on the drawing) of a plurality of dielectrics (20) along a second direction (D2).

[0059] A plurality of first plates (51, 52, 53) may be orthogonal to the first direction (D1) and are positioned at a distance from each other along the first direction (D1). A plurality of second plates (54, 55) may be parallel to the first direction (D1) and are positioned at a distance from each other along the second direction (D2).

[0060] A plurality of first plates (51, 52, 53), a plurality of second plates (54, 55) and a portion of the side wall (13) surround each of the plurality of dielectrics (20) in a lattice shape to form a square unit cell (40). In the cell structure (50), at least one process gas inlet is positioned on the upstream side of each of the plurality of unit cells (40), and at least one process gas outlet is positioned on the downstream side of each of the plurality of unit cells (40).

[0061] A first opening (OP1) for opening each unit cell (40) is positioned on each of the plurality of first plates (51, 52, 53). The first opening (OP1) on the first plate (51) closest to the upper plate (11) is a process gas inlet. The first opening (OP1) on the first plate (52) located between the first layer and the second layer is a process gas outlet and a process gas inlet. The first opening (OP1) on the first plate (53) closest to the lower plate (12) is a process gas outlet.

[0062] Each of the plurality of second plates (54, 55) may be provided with a second opening (OP2) that opens each unit cell (40). The second opening (OP2) enables process gas flow between adjacent unit cells (40) in the second direction (D2).

[0063] The process gas introduced into the main body (10) from the inlet vacuum tube (201) collides with the first plate (51) closest to the upper plate (11) and is distributed and introduced into multiple rows of unit cells (40) located in the first layer through the first opening (OP1) of the first plate (51). Thereafter, the process gas moves to multiple rows of unit cells (40) located in the second layer, and is discharged from the unit cells (40) through the first opening (OP1) of the first plate (53) closest to the lower plate (12) and moves to the discharge vacuum tube (202). At this time, the process gas can move to the unit cells (40) of the adjacent row through the second opening (OP2).

[0064] When a driving voltage is applied to the high voltage electrode (30), plasma is generated in each unit cell (40) by the voltage difference between the high voltage electrode (30) and the cell structure (50) and the main body (10). Inside each unit cell (40), process byproducts in the process gas are decomposed by the plasma, and the solid-state decomposition byproducts are captured on the wall of each unit cell (40). The wall of the unit cell (40) is the outer surface of the dielectric (20), the surfaces of the first and second plates (51, 52, 53, 54, 55) facing the dielectric (20), and the inner surface of the side wall (13). This primary decomposition and capture may be performed in the etching or deposition step of the process chamber.

[0065] Afterwards, cleaning gas is supplied to the main body (10), and a driving voltage is applied to the high voltage electrode (30). In each unit cell (40), ionized gas (e.g., N2) is supplied and plasma is generated. + etc.) and radicals (e.g., fluorine radicals, chlorine radicals, oxygen radicals, etc.) are generated in large quantities. The ionized gases and radicals re-decompose and gasify the decomposition by-products captured on the walls of each unit cell (40). The gasified by-products are discharged in gaseous form by a vacuum pump together with the cleaning gas. This secondary decomposition and gasification can be performed in the cleaning stage of the process chamber.

[0066] Meanwhile, a separate cleaning gas injection pipe (not shown) for supplying cleaning gas may be connected to the inlet vacuum tube (201). In this case, the cleaning gas may be supplied to the main body (10) without being linked to the cleaning step of the process chamber, thereby performing secondary decomposition and gasification. The cleaning gas may include nitrogen trifluoride (NF3), sulfur hexafluoride (SF6), chlorine trifluoride (ClF3), and oxygen (O2).

[0067] Since the cell structure (50) divides a plurality of unit cells (40) together with a portion of the side wall (13), the process gas collides with the wall of each unit cell (40), and the decomposition by-products caused by the plasma are efficiently captured on the wall of each unit cell (40). In addition, the process gas enters each unit cell (40) through the process gas inlet and remains in each unit cell (40) until it is discharged through the process gas outlet. Therefore, the residence time of the process by-products in the plasma increases, so that the decomposition rate caused by the plasma can be increased.

[0068] In a conventional plasma reactor, the dielectric is installed in a hermetically sealed manner in the opening of a vacuum tube, and a high-voltage electrode is fixed to the outside of the dielectric. In this structure, vacuum may leak when the dielectric is damaged by an arc or the like, so an additional device such as a dual chamber is required to prevent this. On the other hand, in the plasma reactor (100) of the present embodiment, even when the dielectric (20) is damaged, vacuum leakage can be suppressed by the first and second O-rings (61, 62), so that vacuum can be maintained without an additional device such as a dual chamber.

[0069] In addition, the plasma reactor (100) of the present embodiment can apply high power to the high voltage electrode (30) by increasing the surface area of ​​the dielectric (20) in contact with the high voltage electrode (30). Under the same voltage-frequency-dielectric thickness conditions, the power (current) is proportional to the surface area of ​​the dielectric (20) in contact with the high voltage electrode (30).

[0070] Fig. 4 is a schematic diagram showing a unit cell of an embodiment and a unit cell of a comparative example. In Fig. 4, (a) shows the embodiment, and (b) shows the comparative example.

[0071] Referring to Fig. 4, the embodiment assumes a case where three unit cells are positioned in parallel. The cell structure (50) constitutes three unit cells, and the three unit cells as a whole have a size of 30 cm (width) x 30 cm (height) x 10 cm (height). One dielectric (20) is configured to have a size of 8 cm (diameter) x 28 cm (length), and the high voltage electrode (30) is positioned inside the dielectric (20). A process gas inlet (OP3) is positioned on the upstream side of each of the three unit cells, and a process gas outlet (not shown) is positioned on the downstream side.

[0072] The unit cell of the comparative example is composed of a ground electrode (70) and has the same size as the unit cell of the embodiment. A process gas inlet (OP4) is located on the upstream side of the unit cell, and a process gas outlet (OP5) is located on the downstream side. A plate-shaped dielectric (20a) having a size of 28 cm (width) x 8 cm (height) is installed on each of the front, rear, left, and right sides of the unit cell, and a high-voltage electrode (30a) is located on the outer surface of the dielectric (20a). The high-voltage electrode (30a) is formed in a plate shape with a size smaller than the dielectric (20a).

[0073] In both the examples and comparative examples, when a driving voltage is applied to the high voltage electrodes (30, 30a), plasma is generated inside the unit cell due to the voltage difference between the high voltage electrode (30) and the cell structure (50) and the voltage difference between the high voltage electrode (30a) and the ground electrode (70).

[0074] In the unit cell of the embodiment, the total surface area of ​​the three dielectrics (20) is 2,110 cm 2 (8π×28×3). In the unit cell of the comparative example, the total surface area of ​​the four dielectrics (20a) is 896 cm 2 (28×8×4). In the structure of the embodiment, the surface area of ​​the dielectric (20) is increased by approximately 2.35 times compared to the comparative example, and as a result, approximately 2.35 times higher power can be applied to the high-voltage electrode (30) than in the comparative example.

[0075] The size of the plasma reactor applicable to vacuum tubes is limited. The plasma reactor (100) of the present embodiment can enhance decomposition and cleaning functions by applying high power to the high-voltage electrode (30) within the limited size. Furthermore, since it can maintain vacuum even when the dielectric (20) is damaged by an arc or the like, it does not require additional devices such as a dual chamber, which is advantageous in reducing manufacturing costs.

[0076] Figure 5 is a cross-sectional view of a plasma reaction device according to the second embodiment.

[0077] Referring to Fig. 5, in the plasma reactor (101) of the second embodiment, the second plate (541, 551) may be formed of a plate without openings. In this case, the process gas moves from the unit cell (40) of the first layer to the unit cell (40) of the second layer, and from the unit cell (40) of the second layer to the exhaust vacuum tube (202). The plasma reactor (101) of the second embodiment has the same or similar configuration as the first embodiment described above, except that the openings in the second plates (541, 551) are omitted.

[0078] Fig. 6 is a cross-sectional view of a plasma reaction device according to the third embodiment.

[0079] Referring to FIG. 6, in the plasma reactor (102) of the third embodiment, the dielectric (20) may be positioned in contact with the cell structure (50). For example, the dielectric (20) may be positioned in contact with the first plate (52, 53) located on the downstream side. At this time, the first opening (OP1) of the downstream first plate (52, 53) may be positioned at a certain distance from the center of the unit cell (40) so that the dielectric (20) does not block the first opening (OP1) of the downstream first plate (52, 53).

[0080] The contact area between the dielectric (20) and the cell structure (50) is not limited to the illustrated example. Even if a part of the dielectric (20) comes into contact with the cell structure (50), the plasma decomposition and cleaning functions can be implemented in the same manner as in the preceding embodiments. The plasma reactor (102) of the third embodiment has a configuration identical or similar to that of the first or second embodiment described above, except that a part of the dielectric (20) comes into contact with the cell structure.

[0081] Fig. 7 is a cross-sectional view of a plasma reaction device according to the fourth embodiment.

[0082] Referring to FIG. 7, the plasma reactor (103) of the fourth embodiment may include a plurality of dielectrics (20) having different diameters (outer diameters). The plurality of dielectrics (20) may have different diameters depending on the layers of the unit cell (40). For example, in a first layer close to the inlet vacuum tube (201), the dielectric (20) may have a first diameter (da1), and in a second layer close to the outlet vacuum tube (202), the dielectric (20) may have a second diameter (da2) smaller than the first diameter (da1).

[0083] The thickness of the dielectric (20) can be the same regardless of the layer of the unit cell (40), and the diameter of the high voltage electrode (30) can be the same as the inner diameter of the dielectric (20). As the diameter of the dielectric (20) increases, the gap between the dielectric (20) and the cell structure (50) decreases, and thus the intensity of the electric field increases under the same operating conditions.

[0084] A larger amount of process byproducts can be decomposed and captured in the unit cells (40) of the first layer, where the process gas first hits among the cell structures (50). By increasing the intensity of the electric field in the unit cells (40) of the first layer, a stronger plasma can be generated, thereby improving the decomposition and cleaning function for the unit cells (40) of the first layer. The plasma reactor (103) of the fourth embodiment has the same or similar configuration as any one of the first to third embodiments described above, except for the diameters of the dielectric (20) and the high voltage electrode (30).

[0085] Fig. 8 is a cross-sectional view of a plasma reaction device according to the fifth embodiment.

[0086] Referring to FIG. 8, in the plasma reactor (104) of the fifth embodiment, the cell structure (50) can partition a plurality of unit cells (40) together with the upper plate (11), side walls (13), and lower plates (12) of the main body (10). A plurality of first plates (51, 52) are positioned at a distance from each other along a first direction (D1) while their edges are in contact with the side walls (13), so that the interior of the main body (10) can be partitioned into a plurality of layers. A plurality of second plates (54, 55) are positioned at a distance from each other along a second direction (D2) while their edges are in contact with the upper plate (11) and the lower plate (12), so that the interior of the main body (10) can be partitioned into a plurality of rows.

[0087] A plurality of first plates (51, 52) may be arranged so that each of the plurality of unit cells (40) has the same height, and a plurality of second plates (54, 55) may be arranged so that each of the plurality of unit cells (40) has the same width. In this case, the internal space of the main body (10) may be divided into a plurality of layers and a plurality of rows of unit cells (40) having a square cross-sectional shape.

[0088] Although the drawing illustrates a case where multiple unit cells (40) form three rows and three layers, the configuration of the unit cells (40) is not limited to the illustrated example. Among the multiple unit cells (40), the unit cells (40) located in the middle row may be positioned parallel to the inlet vacuum tube (201) and the outlet vacuum tube (202) along the first direction (D1).

[0089] In the unit cell (40) of the above-described structure, the number of dielectrics (20) and high voltage electrodes (30) may be different for each layer. For example, in the first and third layers, the dielectrics (20) and high voltage electrodes (30) may be located in the remaining unit cells (40) except for the middle unit cell (40), and in the second layer, the dielectrics (20) and high voltage electrodes (30) may be located in all of the plurality of unit cells (40). In this case, the first layer is a layer close to the inlet vacuum tube (201), the third layer is a layer close to the exhaust vacuum tube (202), and the second layer is located between the first and third layers.

[0090] In the first and third layers, the central unit cell (40) is a space directly connected to the inlet vacuum tube (201) and the exhaust vacuum tube (202), so the dielectric (20) and the high voltage electrode (30) can be omitted to facilitate the flow of process gas.

[0091] And at least one of the plurality of dielectrics (20) may have a different diameter (outer diameter) from the other dielectrics (20). For example, the dielectric (20) located in the central unit cell (40) of the second layer may have a larger diameter than the other dielectrics (20). When the same driving voltage is applied to the plurality of high voltage electrodes (30), the strongest plasma may be generated in the central unit cell (40) of the second layer.

[0092] A plurality of first openings (OP1) positioned on the first plate (51, 52) may be positioned corresponding to the center of each unit cell (40), and at least one first opening (OP1) may have a smaller width than other first openings (OP1). For example, a first opening (OP1) positioned in a unit cell (40) of a middle row among the plurality of unit cells (40) may have a smaller width than other first openings (OP1).

[0093] At least one second opening (OP2) among the plurality of second openings (OP2) positioned on the second plates (54, 55) may be positioned offset from the center of the unit cell (40) to one side. For example, the second opening (OP2) positioned on the unit cell (40) of the first layer may be positioned offset toward the inlet vacuum tube (201), and the second opening (OP2) positioned on the unit cell (40) of the third layer may be positioned offset toward the exhaust vacuum tube (202). Meanwhile, the plurality of second plates (54, 55) may omit the second opening (OP2) in the unit cell (40) of the second layer.

[0094] The plasma reactor (104) of the fifth embodiment has a configuration identical or similar to that of any one of the first to fourth embodiments described above, except for the configuration of the cell structure (50).

[0095] Fig. 9 is a cross-sectional view of a plasma reaction device according to the sixth embodiment.

[0096] Referring to Fig. 9, in the plasma reactor (105) of the sixth embodiment, the cell structure (50) can define a plurality of unit cells (40) together with the upper plate (11) and side walls (13) of the main body (10), and can define a plurality of trap portions (80) together with the side walls (13) and the lower plate (12) of the main body (10). In addition, the dielectrics (20) of each row can have a height difference from the dielectrics (20) of the adjacent row.

[0097] A plurality of second plates (54, 55) are positioned at a distance from each other along the second direction (D2) while their edges are in contact with the upper plate (11) and the lower plate (12), so that the interior of the main body (10) can be partitioned into a plurality of rows. A plurality of first plates (51, 52, 53) are positioned at a distance from each other along the first direction (D1) while their edges are in contact with the side wall (13) and the second plates (54, 55), so that the interior of the main body (10) can be partitioned into a plurality of layers.

[0098] At this time, the dielectrics (20) positioned in a specific column may be positioned at a different height from the dielectrics (20) positioned in the adjacent other columns. For example, the dielectrics (20) in the middle column may be positioned lower toward the exhaust vacuum tube (202) than the dielectrics (20) in the left and right columns. In addition, the plurality of first plates (51, 52, 53) positioned in the middle column may be positioned at a different height along the first direction (D1) from the plurality of first plates (52, 53) positioned in the adjacent other columns.

[0099] The trap section (80) can be located below the unit cells (40) of the left and right columns of the second layer and can capture decomposition byproducts. The trap section (80) is a space surrounded by the first and second plates (53, 54, 55), a portion of the side wall (13), and a portion of the lower plate (12), and in which the dielectric (20) and the high-voltage electrode (30) are not located.

[0100] In this embodiment, the second opening (OP2) provided in each of the two second plates (54, 55) constituting the unit cells (40) of the left and right columns of the first layer functions as a process gas inlet, and the second opening (OP2) provided in each of the two second plates (54, 55) constituting the trap section (80) functions as a process gas outlet.

[0101] The plasma reactor (105) of the sixth embodiment has a configuration identical or similar to that of any one of the first to fourth embodiments described above, except for the height difference between the plurality of dielectrics (20), the height difference between the plurality of first plates (51, 52, 53), and the configuration of the trap section (80).

[0102] Fig. 10 is a cross-sectional view of a plasma reaction device according to the seventh embodiment.

[0103] Referring to FIG. 10, in the plasma reactor (106) of the seventh embodiment, the side wall (13) of the main body (10) may further include an extension portion (132) that extends outward. For example, the side wall (13) may include a basic side wall (131) connected to the upper plate (11) and the lower plate (12), and an extension portion (132) that extends outward from the basic side wall (131). The extension portion (132) may have a cross-section in the shape of the letter D, and the cell structure (50) may define a plurality of unit cells (40) together with the extension portion (132).

[0104] The plasma reactor (106) of the seventh embodiment has a configuration identical or similar to that of any one of the first to fourth embodiments described above, except for the expansion portion (132).

[0105] Fig. 11 is a perspective view showing the external appearance of a plasma reaction device according to the eighth embodiment, and Fig. 12 is a cross-sectional view of the plasma reaction device taken along the CC line of Fig. 11.

[0106] Referring to FIGS. 11 and 12, in the plasma reactor (107) of the eighth embodiment, at least two of the plurality of dielectrics (20) may be arranged to be orthogonal to each other. For example, in the unit cell (40) of the first layer, the plurality of dielectrics (20) may be positioned such that their length direction is parallel to the third direction (D3), and in the unit cell (40) of the second layer, the plurality of dielectrics (20) may be positioned such that their length direction is parallel to the second direction (D2).

[0107] A plurality of second plates (54, 55) can be positioned at a distance from each other along the second direction (D2) in the first layer, and can be positioned at a distance from each other along the third direction (D3) in the second layer, and can define a plurality of unit cells (40) together with the plurality of first plates (51, 52, 53).

[0108] Among the plurality of first openings (OP1) provided in the plurality of first plates (51, 52, 53), at least two first openings (OP1) may be positioned to be orthogonal to each other. For example, among the three first plates (51, 52, 53) shown in the drawing, the first openings (OP1) in the two first plates (51, 53) close to the upper plate (11) and the lower plate (12) may be formed to be long along the second direction (D2), and the first opening (OP1) in the first plate (52) located in the middle may be formed to be long along the third direction (D3).

[0109] In this embodiment, the process gas and process byproducts can pass through the unit cells (40) inside the main body more spatially and uniformly, and as a result, the plasma characteristics of the unit cells (40) can be uniformized, thereby improving the decomposition and cleaning efficiency by plasma. The plasma reactor (107) of the eighth embodiment has a configuration identical or similar to that of the first embodiment or the second embodiment described above, except for the arrangement structure of the dielectric (20) and the second plate (54, 55) and the shape of the first opening (OP1).

[0110] Fig. 13 is a cross-sectional view of a plasma reaction device according to the ninth embodiment.

[0111] Referring to FIG. 13, in the plasma reactor (108) of the ninth embodiment, a plurality of dielectrics (20) can be positioned at a distance from each other along the second direction (D2) in a single layer. Although two dielectrics (20) are illustrated in the drawing, the number of dielectrics (20) is not limited to the illustrated example.

[0112] The cell structure (50) may include a mesh plate (56) positioned between the upper plate (11) and a plurality of dielectrics (20), a first plate (51) positioned between the lower plate (12) and a plurality of dielectrics (20), and a second plate (54) positioned between the plurality of dielectrics (20). The mesh plate (56) and the first plate (51) may be orthogonal to the first direction (D1), and the second plate (54) may be parallel to the first direction (D1). The cell structure (50) may define a plurality of discharge cells (40) together with a portion of the side wall (13).

[0113] The mesh plate (56) allows process gas to pass through a plurality of micro-holes. That is, the plurality of micro-holes function as discharge gas inlets. A first opening (OP1) that opens each discharge cell (40) may be positioned in the first plate (51), and the first opening (OP1) functions as a discharge gas outlet. The discharge vacuum tube (202) may include a protrusion (203) that protrudes from the inside of the main body (10) toward the first plate (51). A portion of the side wall (13) below the first plate (51), the lower plate (12), and the protrusion (203) may form a trap section (80) in which decomposition by-products caused by plasma are captured.

[0114] The plasma reactor (108) of the 9th embodiment has the same or similar configuration as the first or second embodiment described above, except for the number of dielectrics (20) and the mesh plate (56) and the protrusion (203).

[0115] Fig. 14 is a cross-sectional view of a plasma reaction device according to the 10th embodiment.

[0116] Referring to FIG. 14, in the plasma reactor (109) of the 10th embodiment, two dielectrics (20) may be positioned closer to the lower plate (12) than to the upper plate (11) of the main body (10), and may be positioned at a distance along the second direction (D2) with the exhaust vacuum tube (202) therebetween.

[0117] The cell structure (50) can define two unit cells (40) together with a portion of the side wall (13) of the main body (10) and a portion of the lower plate (12). The cell structure (50) can include a first plate (51) positioned between the upper plate (11) and a plurality of dielectrics (20) and covering an exhaust vacuum tube (202), and a plurality of second plates (54, 55) positioned on one side (left or right) of the dielectric (20) along the second direction (D2).

[0118] The first plate (51) may be orthogonal to the first direction (D1) and may have a first opening (OP1) corresponding to each of the two unit cells (40). The two second plates (54, 55) may be positioned at a distance along the second direction (D2) with the exhaust vacuum tube (202) interposed therebetween, and a second opening (OP2) may be positioned in each of the two second plates (54, 55). The first opening (OP1) functions as a process gas inlet, and the second opening (OP2) functions as a process gas outlet.

[0119] The process gas flowing into the main body (10) from the inlet vacuum tube (201) collides with the first plate (51) and is distributed and introduced into two unit cells (40) through the first opening (OP1) of the first plate (51). Then, it is discharged from the two unit cells (40) through the second opening (OP2) of the second plate (54, 55) and moves to the discharge vacuum tube (202). In the two unit cells (40), byproducts in the process gas undergo primary decomposition and capture by plasma, and secondary decomposition and gasification by plasma cleaning.

[0120] The plasma reactor (109) of the 10th embodiment has a configuration identical or similar to that of the first embodiment described above, except for the position and number of the dielectric (20) and the configuration of the cell structure (50).

[0121] Fig. 15 is a cross-sectional view of a high-voltage electrode in a plasma reactor according to the 11th embodiment.

[0122] Referring to Fig. 15, in the plasma reactor of the 11th embodiment, the high voltage electrode (30) may be configured as a hollow cylinder, in which case the weight of the high voltage electrode (30) may be reduced. On the other hand, the interior of the high voltage electrode (30) may be used as a passage for cooling water. Since heat is generated in the high voltage electrode (30) during the plasma generation process, the heat of the high voltage electrode (30) may be reduced using cooling water. For this purpose, a cooling water circulation device, such as a pump, may be connected and installed to the high voltage electrode (30).

[0123] The plasma reactor of the 11th embodiment has a configuration identical or similar to that of any one of the first to tenth embodiments described above, except for the structure of the high voltage electrode (30).

[0124] Fig. 16 is a cross-sectional view of a plasma reaction device according to the 12th embodiment.

[0125] Referring to FIG. 16, the plasma reactor (110) of the 12th embodiment may further include a plasma pretreatment unit (90) installed in an inlet vacuum tube (201). The plasma pretreatment unit (90) may generate any one of capacitively coupled plasma (CCP), inductively coupled plasma (ICP), and transformer coupled plasma (TCP), and may decompose and stabilize byproducts in the process gas.

[0126] In Fig. 16, a plasma pretreatment unit (90) of the CCP type is illustrated as an example. The plasma pretreatment unit (90) of the CCP type may include a dielectric (91) and a high voltage electrode (92) positioned on the outer surface of the dielectric (91). The high voltage electrode (92) may be positioned at a distance from the inlet vacuum tube (201) along the first direction (D1) so as not to short-circuit with the inlet vacuum tube (201). When a driving voltage is applied to the high voltage electrode (92), plasma is generated inside the dielectric (91) due to the voltage difference between the high voltage electrode (92) and the inlet vacuum tube (201).

[0127] The plasma reactor (110) of the 12th embodiment has a configuration identical or similar to that of any one of the first to eleventh embodiments described above, except for the plasma pretreatment unit (90). In Fig. 16, the plasma reactor of the 6th embodiment is illustrated as an example.

[0128] Meanwhile, the cross-section of the unit cell (40) can be configured in a shape other than a square, and the cross-sections of the dielectric (20) and the high-voltage electrode (30) can also be configured in a shape other than a circle. Fig. 17 is a schematic diagram showing various modified examples of the unit cell.

[0129] Referring to FIG. 17, the cell structure (50) may include a corner extension (57) extending from the corner side of each unit cell (40) toward the center of the unit cell (40) (see (a) to (e)). The corner extension (57) may be configured in a triangle shape so that the cross-section of the unit cell (40) becomes an octagon (see (a) to (d)). On the other hand, the corner extension (57) may be formed in a curved shape (see (e)).

[0130] Among the cell structures (50), the first opening (OP1) of the first plate (51, 52) is positioned one at a time at the center of each unit cell (40) (see (a), (b), (d) to (f)), or may be positioned in multiple numbers at the center of each unit cell (40) (see (c)). The second opening (OP2) of the second plate (54, 55) is positioned one at a time at the center of each unit cell (40) (see (b), (e)), or may be omitted (see (a), (c), (d), (f)).

[0131] The high voltage electrode (30) may be cylindrical in shape (see (a) to (c), (e)) or may be formed in a hollow cylinder shape (see (d)). On the other hand, the dielectric (20) may be a hollow square tubular shape, and the high voltage electrode (30) may be formed in a square column shape (see (f)).

[0132] In addition, the openings (OP1, OP2) of the cell structure (50) can be provided in various numbers and shapes. Fig. 18 is a schematic diagram showing a first plate corresponding to one unit cell. Although Fig. 18 illustrates the first opening of the first plate, the second opening of the second plate can also be provided in the same shape as the first opening illustrated in Fig. 18.

[0133] Referring to FIG. 18, each unit cell may have one first opening (OP1) in a rectangular shape parallel to the longitudinal direction (third direction (D3)) of the dielectric (20) (see (a)), or a plurality of first openings (OP1) may be positioned at a distance from each other along the second direction (D2) and the third direction (D3) (see (b), (c)). Each of the plurality of first openings (OP1) may be formed in a rectangular shape (see (b)) or an oval shape (see (c)). Alternatively, the first plate may be replaced with a mesh plate (56) having a plurality of microholes (see (d)).

[0134] Figure 19 is a configuration diagram of a semiconductor processing facility equipped with a plasma reaction device according to one embodiment.

[0135] Referring to FIG. 19, the semiconductor process equipment includes a process chamber (300) in which a deposition or etching process is performed, a vacuum pump (400) connected to the process chamber (300) by a vacuum tube (201, 202) and evacuating the interior of the process chamber (300) to a vacuum, and a plasma reaction device (100) connected to the vacuum tube (201, 202). The plasma reaction device (100) is a plasma reaction device according to any one of the above-described embodiments, and FIG. 19 illustrates the plasma reaction device (100) according to the first embodiment as an example.

[0136] The plasma reactor (100) can apply higher power to the high-voltage electrode (30) by increasing the surface area of ​​the dielectric (20), and can maintain vacuum even when the dielectric (20) is damaged. Therefore, the plasma reactor (100) can exhibit maximum decomposition-capture-cleaning capability under limited size conditions, and can reduce manufacturing costs because no additional device is required to suppress vacuum leakage.

[0137] A plasma pretreatment unit (90) may be installed in the inlet vacuum tube (201). The plasma pretreatment unit (90) may generate any one of capacitively coupled plasma (CCP), inductively coupled plasma (ICP), and transformer coupled plasma (TCP), and decomposes and stabilizes byproducts in the process gas.

[0138] A scrubber device (500) may be installed after the vacuum pump (400). Conventional scrubber devices typically include a burner that uses natural gas as fuel. However, the burner decomposes process byproducts at high temperatures, thereby emitting a large amount of carbon oxides and nitrogen oxides. Since the plasma reactor (100) according to the present disclosure decomposes and gasifies process byproducts with high efficiency, the scrubber device (500) may replace the conventional burner with an electric heater or omit the burner. The wet scrubber device (500) without the burner neutralizes the decomposed fluorine byproducts, which is advantageous for reducing fine dust and achieving carbon neutrality.

[0139] Although the preferred embodiments of the present disclosure have been described above, the present disclosure is not limited thereto, and various modifications can be made within the scope of the claims, the detailed description of the invention, and the attached drawings, and it is obvious that this also falls within the scope of the present disclosure.

[0140] (Explanation of symbols)

[0141] 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110: Plasma reactor

[0142] 10: Body 11: Top plate

[0143] 12: Lower plate 13: Side wall

[0144] 20: Dielectric 30: High voltage electrode

[0145] 40: Unit cell 50: Cell structure

[0146] 51, 52, 53: 1st plate 54, 55: 2nd plate

[0147] OP1: First opening OP2: Second opening

[0148] 56: Mesh plate 60: Insulating support

[0149] 61: 1st O-ring 62: 2nd O-ring

[0150] 70: Ground electrode 80: Trap section

[0151] 90: Plasma pretreatment unit 201: Inlet vacuum tube

[0152] 202: Exhaust vacuum tube 300: Process chamber

[0153] 400: Vacuum pump 500: Scrubber device

Claims

1. A body that is connected to a vacuum tube and through which process gas passes; A plurality of dielectrics located inside the main body and formed in a tubular shape; A cell structure fixed to the inside of the main body, grounded together with the main body, and defining a plurality of unit cells that surround each of the plurality of dielectrics together with the main body; and A plurality of high-voltage electrodes located inside each of the plurality of dielectrics and receiving a driving voltage from a power source to generate plasma in the plurality of unit cells. Includes, A plasma reactor having a process gas inlet located on the upstream side of each of the plurality of unit cells and a process gas outlet located on the downstream side of each of the plurality of unit cells.

2. In paragraph 1, The above plurality of unit cells are positioned adjacent to each other to form a plurality of rows and a plurality of layers, The above cell structure is, A plurality of first plates perpendicular to the first direction, which is the flow direction of the process gas, A plasma reactor comprising a plurality of second plates positioned parallel to the first direction between the plurality of first plates.

3. In paragraph 2, A plasma reactor in which at least one of the plurality of dielectrics is in contact with a downstream first plate among the plurality of first plates.

4. In paragraph 2, A plasma reactor in which the plurality of dielectrics have different sizes for each layer in the plurality of layers.

5. In paragraph 2, The above plurality of genetic materials are provided in different numbers per layer in the plurality of layers, A plasma reactor in which at least one of the plurality of dielectrics has a diameter different from that of the other dielectrics.

6. In paragraph 2, A plasma reactor in which each of the plurality of dielectrics and the plurality of first plates located in one of the plurality of columns is located at a different height along the first direction from the plurality of dielectrics and the plurality of first plates located in another column.

7. In paragraph 2, The above body includes an upper plate, a lower plate, and a side wall, The above side wall includes a basic side wall connected to the upper plate and the lower plate, and an extension extending outward from the basic side wall, The above cell structure is a plasma reactor that divides the plurality of unit cells together with the expansion portion.

8. In paragraph 2, A plasma reactor in which at least two dielectrics having different layers among the plurality of dielectrics are positioned orthogonally to each other.

9. In paragraph 1, The above multiple unit cells form a single layer and are positioned adjacent to each other, The above cell structure is, A mesh plate and a first plate positioned orthogonal to the first direction, which is the flow direction of the process gas, with the plurality of dielectrics interposed therebetween, A plasma reactor comprising a second plate positioned parallel to the first direction between the mesh plate and the first plate.

10. In paragraph 1, The above body includes an upper plate, a lower plate, and a side wall, The above plurality of dielectrics are arranged close to the lower plate and the side wall at a distance from each other, A plasma reactor in which the cell structure comprises a first plate orthogonal to a first direction, which is a flow direction of a process gas, and a plurality of second plates parallel to the first direction, and which defines the plurality of unit cells together with the lower plate and a portion of the side wall.

11. In paragraph 1, The above body includes a side wall in which a plurality of through holes are located, Each of the above plurality of dielectrics is fitted into the through hole, A plasma reactor in which both ends of each of the plurality of high-voltage electrodes are connected to an insulating support via an O-ring.

12. In paragraph 1, A plasma reactor in which at least one of the plurality of high voltage electrodes is formed as a hollow tube and accommodates cooling water in the internal space.

13. In paragraph 1, The above vacuum tube includes an inlet vacuum tube connected to the inlet of the main body, A plasma reactor in which a plasma pretreatment unit for generating plasma of any one of capacitively coupled plasma (CCP), inductively coupled plasma (ICP), and transformer-coupled plasma (TCP) is installed in the above-mentioned inlet vacuum tube.

14. In paragraph 1, The above body includes an upper plate, a lower plate, and a side wall, A plasma reactor in which the cell structure and a portion of the lower plate and the side wall define a plurality of trap sections.

15. In a process gas treatment method using a plasma reaction device according to any one of clauses 1 to 14, A first decomposition and capture step of generating plasma by applying a driving voltage to the high voltage electrode to decompose byproducts in the process gas into plasma and capture the solid decomposition byproducts on the walls of the plurality of unit cells; A process gas treatment method including a re-decomposition step of secondary decomposition and gasification of captured decomposition by-products by plasma cleaning by applying a driving voltage to the high-voltage electrode simultaneously with supplying cleaning gas to generate plasma.

16. In paragraph 15, A process gas treatment method wherein the above first decomposition and capture step is performed in a deposition or etching step of a process chamber, and the re-decomposition step is performed in a cleaning step of the process chamber.

17. A process chamber in which either deposition or etching process is performed and process gas is discharged; A vacuum pump connected to the process chamber by a vacuum tube to exhaust the interior of the process chamber; and A plasma reactor according to any one of claims 1 to 14, which is connected to the above vacuum tube, decomposes and captures by-products in a process gas by plasma, and redisassembles and gasifies the captured decomposition by-products by plasma cleaning. Semiconductor process equipment including.

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