Plasma chamber with side gas feeder forming scroll movement

Abstract

The present invention relates to a plasma chamber provided with a side gas feeder that forms a vortex motion, the plasma chamber comprising: a housing provided with a mounting part in which a wafer is mounted; and side gas feeders that are provided on a side surface of the housing and that inject gas into the housing, the housing being provided with a plurality of side gas feeders, the side gas feeders including nozzles having nozzle holes through which gas is injected, and the side gas feeders injecting gas toward a wall surface of the housing.

Description

Technical Field

[0001] The present invention relates to a plasma chamber with a side gas feeder that forms a swirl motion. More specifically, the plasma chamber with a side gas feeder that forms a swirl motion adjusts the injection direction of the gas injected from the side gas feeder toward the wall surface of the shell, so that the gas injected from the nozzle forms a swirl motion in the chamber, thereby maintaining a uniform etching rate in the chamber. Background Art

[0002] Generally speaking, in a process of manufacturing a semiconductor, it is very important to ensure uniformity. The uniformity of the semiconductor can be ensured or adjusted in an etching process in the process of manufacturing the semiconductor.

[0003] The semiconductor etching process can be performed inside a plasma chamber. The plasma chamber can form plasma in an internal reaction space and use the plasma to perform the semiconductor etching process.

[0004] A plasma source for forming plasma is provided at the upper portion of the plasma chamber. Typical examples of the plasma source include a capacitively coupled plasma (CCP) source and an inductively coupled plasma (ICP) source.

[0005] In the etching process, the gas distribution inside the plasma chamber is an important factor for maintaining a uniform etching rate. Generally speaking, in order to maintain a uniform etching rate, a shower head design is used in a chamber using a capacitively coupled plasma source, and a bottom gas feeder (BGF), a center gas feeder (CGF), and a side gas feeder (SGF) are used in a chamber using an inductively coupled plasma.

[0006] Although inductively coupled plasma (ICP) can increase the etching rate compared to capacitively coupled plasma (CCP), in the case of inductively coupled plasma (ICP), there are problems such as low selectivity and poor process repeatability.

[0007] In addition, the existing inductively coupled plasma (ICP) injects the main gas through the central gas feeder and injects a small amount of gas through the side gas feeder to compensate for the low etching rate at the edge of the wafer. This method can adjust the etching rate at the edge of the wafer, so it is expected that the line width uniformity can be improved.

[0008] However, the nozzle of the side gas feeder of the conventional inductively coupled plasma (ICP) is directed toward the wafer, and therefore, in the case of a gas with a large molecular weight, there is a problem that the etching rate becomes non-uniform.

[0009] Specifically, if the main gas is injected from the central gas feeder and a small amount of gas is injected from the side gas feeder, the gas from the side gas feeder flows into the space between the chamber and the wafer, so there is a problem that the effect of improving the line width cannot be obtained.

[0010] On the other hand, if the amount of gas injected from the side gas feeder is increased, the line width uniformity of the entire wafer is affected, and there is a problem that a result different from the expected result is obtained. Summary of the invention

[0011] Technical issues

[0012] The present invention aims to solve the above-mentioned problems. More specifically, the present invention relates to a plasma chamber with a side gas feeder that forms a swirl motion, wherein the injection direction of the gas injected from the side gas feeder is adjusted toward the wall surface of the shell, so that the gas injected from the nozzle forms a swirl motion in the chamber, thereby maintaining a uniform etching rate inside the chamber.

[0013] Problem Solving Solutions

[0014] The plasma chamber of the present invention with a side gas feeder that forms a vortex motion, which is intended to solve the above-mentioned problem, is a plasma chamber that forms plasma for etching a wafer. The plasma chamber with a side gas feeder that forms a vortex motion is characterized in that it includes: a shell having a placement portion for placing the above-mentioned wafer; and a side gas feeder, which is provided on the side of the above-mentioned shell and sprays gas into the interior of the above-mentioned shell, and the above-mentioned shell is provided with a plurality of the above-mentioned side gas feeders, and the above-mentioned side gas feeders include a nozzle with a nozzle hole for spraying gas, and the above-mentioned side gas feeders spray gas toward the wall of the above-mentioned shell.

[0015] In the plasma chamber provided with the side gas feeder that forms a swirling motion according to the present invention for solving the above-mentioned problems, the plurality of side gas feeders provided in the housing may be provided at positions having the same height from the placement portion.

[0016] In the plasma chamber of the present invention having a side gas feeder for forming a vortex motion, which is intended to solve the above-mentioned problem, the direction of the gas ejected from the above-mentioned side gas feeder can be a direction on a plane extending in parallel with a plane formed by the above-mentioned placement portion on which the above-mentioned wafer is placed.

[0017] With regard to the plasma chamber of the present invention having a side gas feeder for forming a vortex motion, which is intended to solve the above-mentioned problem, when any one of the multiple side gas feeders provided in the above-mentioned shell is referred to as a first side gas feeder, and the side gas feeder adjacent to the above-mentioned first side gas feeder is referred to as a second side gas feeder, the above-mentioned first side gas feeder can spray gas in the direction of the above-mentioned second side gas feeder.

[0018] With regard to the plasma chamber of the present invention having a side gas feeder that forms a vortex motion and that is intended to solve the above-mentioned problem, when any one of the plurality of side gas feeders provided in the shell is referred to as a first side gas feeder, and the side gas feeder adjacent to the first side gas feeder is referred to as a second side gas feeder, and the side gas feeder adjacent to the second side gas feeder in the opposite direction to the direction in which the first side gas feeder is adjacent is referred to as a third side gas feeder, the first side gas feeder can spray gas in a direction between the second side gas feeder and the third side gas feeder.

[0019] With regard to the plasma chamber of the present invention having a side gas feeder for forming a vortex motion, which is intended to solve the above-mentioned problem, n side gas feeders can be provided on the above-mentioned shell, wherein n is a natural number greater than or equal to 3, and n is the number of side gas feeders.

[0020] In the plasma chamber provided with the side gas feeder that forms a swirling motion according to the present invention for solving the above-mentioned problems, the plurality of side gas feeders provided in the housing may be provided in the housing in the form of a regular polygon.

[0021] With regard to the plasma chamber of the present invention having a side gas feeder for forming a vortex motion which is intended to solve the above-mentioned problem, when the number of the side gas feeders at the same height from the above-mentioned mounting portion is referred to as n, an angle formed by one of the side gas feeders and two adjacent side gas feeders on both sides of the side gas feeder can be 180×(n-2) / n degrees.

[0022] The plasma chamber provided with the side gas feeder for forming a swirling motion according to the present invention for solving the above-mentioned problems may further include a central gas feeder provided on the upper portion of the housing and injecting gas into the interior of the housing.

[0023] In the plasma chamber provided with the side gas feeder for forming a swirling motion according to the present invention for solving the above-mentioned problems, the gas injected from the side gas feeder may be a gas having a molecular weight heavier than that of the gas injected from the central gas feeder.

[0024] In the plasma chamber of the present invention having a side gas feeder for forming a vortex motion, which is intended to solve the above-mentioned problem, the plasma formed in the internal space of the shell contains ions and free radicals, and the wafer can be etched by the synergy effect of the ions and the free radicals.

[0025] In the plasma chamber provided with a side gas feeder that forms a swirling motion according to the present invention, which is intended to solve the above-mentioned problems, the nozzle hole may be formed in a circular shape having a diameter of 0.1 to 1 mm.

[0026] In the plasma chamber of the present invention having a side gas feeder that forms a vortex motion and is intended to solve the above-mentioned problem, the side gas feeder provided in the housing may be provided with a controller that adjusts the flow rate or speed of the gas ejected from the side gas feeder.

[0027] Effects of the Invention

[0028] The present invention relates to a plasma chamber having a side gas feeder for forming a swirl motion, wherein the injection direction of the gas injected from the side gas feeder is adjusted toward the wall surface of a shell, so that the gas injected from the nozzle forms a swirl motion in the chamber, thereby having the advantage of being able to maintain a uniform etching rate in the chamber.

[0029] In addition, the present invention adjusts the direction of the gas ejected from a side gas feeder provided in the shell to the direction of another side gas feeder adjacent to the one side gas feeder, so that the gas ejected from the nozzle can form a swirl motion in the chamber, thereby having the advantage of being able to maintain a uniform etching rate inside the chamber.

[0030] In addition, the present invention adjusts the injection direction of the gas injected from the side gas feeder toward the wall of the shell, so that the speed or flow rate of the gas injected from one side gas feeder can reach another adjacent side gas feeder, thereby having the advantage of being able to prevent the gas injected from the side gas feeder from hitting the wall of the shell.

[0031] In addition, the present invention is configured so that the speed or flow rate of gas injected from one side gas feeder can reach another adjacent side gas feeder, so there is an advantage that the gas injected from one side gas feeder can be forced by the other side gas feeder to form a swirl motion.

[0032] At the same time, the present invention uses a side gas feeder and a central gas feeder in the chamber at the same time, and sprays heavy molecule gas through the side gas feeder, thereby having the advantages of being able to improve the uniformity of the etching rate and being able to improve the etching rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 is a diagram illustrating a plasma chamber according to an embodiment of the present invention.

[0034] Figure 2 is a diagram showing a plasma chamber provided with a side gas feeder and a central gas feeder according to an embodiment of the present invention.

[0035] Figure 3 is a diagram showing a plurality of side gas feeders provided on a housing according to an embodiment of the present invention.

[0036] Figure 4 2 is a diagram showing that the direction of gas ejected from a first-side gas feeder is the direction of a second-side gas feeder according to an embodiment of the present invention.

[0037] Figure 5 2 is a diagram showing that the direction of gas ejected from the first side gas feeder is a direction between the second side gas feeder and the third side gas feeder according to an embodiment of the present invention.

[0038] Figure 6 1 is a diagram showing angles between side gas feeders when the housing includes six side gas feeders according to an embodiment of the present invention.

[0039] FIG. 7 is a diagram showing angles between side gas feeders when a housing includes four side gas feeders according to an embodiment of the present invention.

[0040] FIG. 8 is a diagram showing angles between side gas feeders when a housing includes eight side gas feeders according to an embodiment of the present invention. DETAILED DESCRIPTION

[0041] This specification explains the principles of the present invention and discloses various embodiments to clarify the scope of the present invention and enable those skilled in the art to implement the present invention. The disclosed embodiments can be implemented in various ways.

[0042] The expressions "including" or "may include" etc. that can be used in various embodiments of the present invention refer to the existence of the corresponding functions, actions or constituent elements of the invention (disclosure), and do not limit the additional one or more functions, actions or constituent elements, etc. In addition, in various embodiments of the present invention, the terms "including" or "having" etc. are intended to specify the existence of the features, numbers, steps, actions, constituent elements, parts or combinations thereof recorded in the specification, and should be understood as not excluding in advance the existence or additional possibility of one or more other features or numbers, steps, actions, constituent elements, parts or combinations thereof.

[0043] When it is mentioned that a certain component is "connected or coordinated" with another component, although the above-mentioned certain component may be directly connected or directly coordinated with the above-mentioned other component, it should be understood that there may be other new components between the above-mentioned certain component and the above-mentioned other component. On the contrary, when it is mentioned that a certain component is "directly connected" or "directly coordinated" with another component, it should be understood that there are no other new components between the above-mentioned certain component and the above-mentioned other component.

[0044] The terms "first", "second", etc. used in this specification can be used to describe various components, but each component should not be limited by each term. Each term is used only to distinguish one component from other components.

[0045] The present invention relates to a plasma chamber with a side gas feeder that forms a swirl motion. The plasma chamber with a side gas feeder that forms a swirl motion adjusts the injection direction of the gas injected from the side gas feeder toward the wall surface of the shell, so that the gas injected from the nozzle forms a swirl motion in the chamber, thereby maintaining a uniform etching rate in the chamber.

[0046] A plasma chamber having a side gas feeder that forms a vortex motion according to an embodiment of the present invention can improve the uniformity of an etching rate in a chamber using heavy molecules such as metal etching or oxide etching.

[0047] However, the present invention is not limited thereto, and the plasma chamber equipped with a side gas feeder that forms a vortex motion according to the embodiment of the present invention can of course be applied to chambers that use various molecules.

[0048] The plasma chamber provided with a side gas feeder capable of forming a swirl motion according to an embodiment of the present invention includes a housing 110 and a side gas feeder 120 .

[0049] Reference Figure 1 The housing 110 has a reaction space inside for etching the wafer 10 by plasma. The housing 110 may be an outer wall of a plasma chamber according to an embodiment of the present invention, and has a space inside.

[0050] The housing 110 may include a seating portion 111 for seating the wafer 10 , and the wafer 10 may be mounted on the seating portion 111 . When the wafer 10 is mounted in the housing 110 , the wafer 10 may be etched by plasma formed in the housing 110 .

[0051] The seating portion 111 may be a plate provided in the housing 110 and seating the wafer 10 , or may be a wafer chuck seating and supporting the wafer 10 .

[0052] According to an embodiment of the present invention, a plasma source 113 for forming plasma may be provided on the upper portion of the housing 110. Figure 1 The plasma source 113 may include a coil 114 and a radio frequency power generator 115 , and plasma may be formed inside the housing 110 through the coil 114 and the radio frequency power generator 115 .

[0053] The plasma chamber with a side gas feeder according to an embodiment of the present invention may further include a bias RF source 116 capable of applying a bias to the placement portion 111. Figure 1 The bias RF source 116 applies a bias voltage (Bias) to the placement portion 111, so that a bias voltage can be applied to the plasma during the etching process.

[0054] A plasma chamber having a side gas feeder that forms a vortex motion according to an embodiment of the present invention can solve the problems of a method using an existing inductively coupled plasma (ICP) source and improve it.

[0055] In addition, the plasma chamber with the side gas feeder according to the embodiment of the present invention may be a synergistic resonance ICP (SRICP) using a resonance phenomenon and a synergy effect.

[0056] Specifically, the plasma formed in the inner space of the housing 110 of the plasma chamber with a side gas feeder according to an embodiment of the present invention may include ions and radicals, and the wafer 10 may be etched by the synergy effect of the ions and the radicals.

[0057] Plasma is generally composed of electrons, ions, and radicals. When observing the existing methods of etching wafers by plasma, the dominant species in the plasma etching process is formed by one of ions or radicals. Specifically, in the existing methods of etching wafers by plasma, metal etching mainly uses radicals, and oxide etching mainly uses ions.

[0058] According to the plasma chamber with the side gas feeder according to the embodiment of the present invention, during the plasma etching process, the dominant species are not formed by one of ions or radicals, but ions and radicals can be used simultaneously.

[0059] That is, in the plasma chamber with a side gas feeder according to an embodiment of the present invention, during the etching process, rather than performing a reaction dominated by ions or a reaction dominated by radicals, it is better to use a process field in which ions and radicals work together to produce a synergy effect.

[0060] More specifically, the plasma chamber with a side gas feeder according to an embodiment of the present invention uses ions and radicals simultaneously, thereby maintaining a high etch rate and improving selectivity through a resonance phenomenon and a synergy effect between ions and radicals.

[0061] Reference Figure 2 The side gas feeder 120 is provided at a side surface of the housing 110 and injects gas into the interior of the housing 110. The housing 110 may include a plurality of side gas feeders 120.

[0062] The side gas feeder 120 includes a nozzle 121 having a nozzle hole 122 for injecting gas, and a plurality of the nozzles 121 may be provided in the housing 110 .

[0063] Reference Figure 3The plurality of side gas feeders 120 provided in the housing 110 may be provided at the same height from the seating portion 111. In addition, the direction of the gas ejected from the plurality of side gas feeders 120 provided in the housing 110 may be a direction on a plane extending in parallel with a plane formed by the seating portion 111 on which the wafer 10 is seated.

[0064] The plurality of side gas feeders 120 may inject gas in one plane, and the plurality of side gas feeders 120 may be provided at the same height from the seating portion 111 and arranged on one plane.

[0065] Specifically, the plurality of side gas feeders 120 may be disposed on a plane extending in a direction parallel to a plane formed by the seating portion 111 at a predetermined height h away from the seating portion 111 .

[0066] In addition, the plurality of side gas feeders 120 may spray gas toward the wall surface of the housing 110 on a plane extending in a direction parallel to a plane formed by the seating portion 111 at a predetermined height h from the seating portion 111 .

[0067] Reference Figure 3 and Figure 4 The plurality of side gas feeders 120 provided in the housing 110 may be provided in the housing 110 in the form of a regular polygon. Specifically, the plurality of side gas feeders 120 may be provided in the housing 110 in the form of a regular polygon on a plane extending in a direction parallel to a plane formed by the seating portion 111.

[0068] Reference Figure 3 and Figure 4 The side gas feeder 120 may spray gas toward the wall of the housing 110. The nozzle hole 122 of the side gas feeder 120 faces the wall of the housing 110, and a plurality of the side gas feeders 120 may form a certain angle with the wall of the housing 110 and spray gas.

[0069] Specifically, refer to Figure 4 The cross section of the housing 110 may be formed in a circular shape. If a tangent line is formed at a point where the housing 110 formed in a circular shape contacts the side gas feeder 120, an angle formed by the tangent line and the direction in which the gas is ejected from the side gas feeder 120 may be formed at a certain angle.

[0070] According to an embodiment of the present invention, the direction of the gas ejected from one side gas feeder 120 provided in the housing 110 may be the direction of another side gas feeder 120 adjacent to the one side gas feeder 120 .

[0071] Reference Figure 4 When any one of the multiple side gas feeders 120 provided in the shell 110 is referred to as a first side gas feeder 123, and the side gas feeder 120 adjacent to the first side gas feeder 123 is referred to as a second side gas feeder 124, the first side gas feeder 123 can spray gas in the direction of the second side gas feeder 124.

[0072] That is, the gas injected from the first side gas feeder 123 may be injected toward the second side gas feeder 124. If the gas injected from the first side gas feeder 123 is injected toward the second side gas feeder 124, the gas injected from the first side gas feeder 123 may receive force from the second side gas feeder 124 before hitting the wall surface of the housing 110.

[0073] Since the gas injected from the first side gas feeder 123 receives force from the second side gas feeder 124 , the gas injected from the first side gas feeder 123 may be rotated by the second side gas feeder 124 instead of hitting the wall of the shell 110 .

[0074] The gas injected from the first side gas feeder 123 is affected by gravity. The gas injected from the first side gas feeder 123 rotates and descends along the gravity direction to form a downward swirl motion.

[0075] If the gas injected from the first-side gas feeder 123 forms a downward swirl motion and contacts the wafer 10 , the gas further moves due to centrifugal force even when contacting the wafer 10 , thereby generating a diffusion effect.

[0076] Through this diffusion effect, the gas reacts with nearby particles, thereby improving the uniformity of the etching rate.

[0077] Reference Figure 4If the side gas feeder 120 adjacent to the second side gas feeder 124 in the opposite direction to the direction adjacent to the first side gas feeder 123 is set as the third side gas feeder 125, the second side gas feeder 124 may inject gas toward the third side gas feeder 125. In addition, the third side gas feeder 125 may inject gas toward a fourth side gas feeder provided in the opposite direction to the direction adjacent to the second side gas feeder 124.

[0078] In this way, the plurality of side gas feeders 120 provided in the housing 110 may spray gas toward the adjacent side gas feeders 120 , so that the gas sprayed from the side gas feeders 120 forms a downward swirl motion.

[0079] The side gas feeder 120 provided in the housing 110 according to the embodiment of the present invention may include a controller for adjusting a speed or a flow rate of the gas injected from the side gas feeder 120 .

[0080] As described above, the gas injected from one side gas feeder 120 provided in the housing 110 can only be subjected to force from the other side gas feeder 120 to form a downward swirl motion when it moves to the other side gas feeder 120 adjacent thereto.

[0081] If the gas injected from one side gas feeder 120 cannot reach the other side gas feeder 120 , it is difficult to form a downward swirl motion.

[0082] Therefore, the gas injected from one side gas feeder 120 must be injected at a flow rate or speed that can move to another adjacent side gas feeder 120. The controller can adjust the speed or flow rate of the gas injected from the side gas feeder 120, and the flow rate or speed of the gas can be adjusted by the controller so that the gas injected from one side gas feeder 120 can move to another adjacent side gas feeder 120.

[0083] In addition, according to an embodiment of the present invention, the speed or flow rate of the gas ejected from one side gas feeder 120 and the cross-sectional area (A) of the nozzle hole 122 formed in one side gas feeder 120 can also be adjusted so that the gas ejected from one side gas feeder 120 can move to another adjacent side gas feeder 120.

[0084] According to another embodiment of the present invention, the first-side gas feeder 123 may also spray gas in a direction between the second-side gas feeder 124 and the third-side gas feeder 125 .

[0085] When any one of the plurality of side gas feeders 120 provided in the housing 110 is referred to as a first side gas feeder 123, a side gas feeder 120 adjacent to the first side gas feeder 123 is referred to as a second side gas feeder 124, and a side gas feeder 120 adjacent to the second side gas feeder 124 in a direction opposite to a direction in which the first side gas feeder 123 is adjacent is referred to as a third side gas feeder 125, Figure 5 As shown, the first-side gas feeder 123 may also spray gas toward a direction between the second-side gas feeder 124 and the third-side gas feeder 125 .

[0086] Even if the gas injected from the first side gas feeder 123 is injected in a direction slightly deviated from the direction of the second side gas feeder 124 , the gas can receive force from the second side gas feeder 124 .

[0087] However, if the gas ejected from the first side gas feeder 123 deviates greatly from the direction of the second side gas feeder 124 , the gas ejected from the first side gas feeder 123 cannot receive force from the second side gas feeder 124 .

[0088] Therefore, the gas injected from the first side gas feeder 123 is preferably injected in the direction between the second side gas feeder 124 and the third side gas feeder 125. In addition, the gas injected from the second side gas feeder 124 may be injected in the direction between the third side gas feeder 125 and the fourth side gas feeder.

[0089] In this way, the plurality of side gas feeders 120 provided in the housing 110 may inject gas toward adjacent side gas feeders 120 , so that the gas injected from the side gas feeders 120 forms a downward swirl motion.

[0090] Of course, in this case, the speed or flow rate of the gas ejected from the side gas feeder 120 can also be adjusted so that the gas ejected from the first side gas feeder 123 reaches between the second side gas feeder 124 and the third side gas feeder 125, and the cross-sectional area of ​​the nozzle hole 122 can also be adjusted.

[0091] According to an embodiment of the present invention, the housing 110 may be provided with n side gas feeders 120. Here, n is a natural number greater than or equal to 3, and n may be the number of the side gas feeders.

[0092] According to an embodiment of the present invention, it is preferred that three or more side gas feeders 120 are provided. Specifically, the housing 110 may be provided with three or more side gas feeders 120, and the three side gas feeders 120 may be arranged on one plane.

[0093] When there are two side gas feeders 120 , it is difficult to form a swirl motion, and thus it is preferable that three or more side gas feeders 120 are provided.

[0094] More specifically, in order to form a swirl motion by the side gas feeder 120 , it is preferable that three to eight side gas feeders 120 are provided in the housing 110 .

[0095] However, the number of the side gas feeders 120 provided in the housing 110 is not limited to eight, and the number of the side gas feeders 120 provided in the housing 110 may be more than eight.

[0096] According to an embodiment of the present invention, a plurality of the side gas feeders 120 may be provided in the housing 110 in the form of a regular polygon. According to an embodiment of the present invention, when the number of the side gas feeders 120 provided at the same height from the placement portion 111 is referred to as n, an angle formed by one of the side gas feeders and two side gas feeders adjacent to the side gas feeders on both sides of the side gas feeder may be 180×(n-2) / n degrees (here, since the number of the side gas feeders 120 provided in the housing 110 is 3 or more, the n in the formula of 180×(n-2) / n may be greater than 3).

[0097] like Figure 6 As shown, when the number of the side gas feeders 120 located at the same height from the placement portion 111 is 6, the angle formed by one side gas feeder and two side gas feeders adjacent to the side gas feeder can be 120 degrees.

[0098] As shown in FIG. 7 , when there are four side gas feeders 120 located at the same height from the placement portion 111 , an angle formed by one side gas feeder and two adjacent side gas feeders on both sides of the side gas feeder may be 90 degrees.

[0099] Specifically, if Figure 6 As shown, when the number of the side gas feeders 120 is 6, the angle formed by the line connecting the second side gas feeder 124 to the first side gas feeder 123 and the line connecting the second side gas feeder 124 to the third side gas feeder 125 can be 120 degrees.

[0100] In addition, as shown in FIG7 , when the number of the side gas feeders 120 is 4, the angle formed by the line connecting the second side gas feeder 124 to the first side gas feeder 123 and the line connecting the second side gas feeder 124 to the third side gas feeder 125 can be 90 degrees.

[0101] According to an embodiment of the present invention, if a tangent is formed at a location where the circular shell 110 contacts the side gas feeder 120 , an angle formed by the tangent and the direction in which gas is ejected from the side gas feeder 120 may be 20 to 60 degrees.

[0102] As described above, the housing 110 is preferably provided with 3 to 8 side gas feeders 120. Referring to Fig. 8, when the housing 110 is provided with 8 side gas feeders 120, an angle formed by a line connecting the second side gas feeder 124 to the first side gas feeder 123 and a line connecting the second side gas feeder 124 to the third side gas feeder 125 may be 135 degrees.

[0103] According to an embodiment of the present invention, the second side gas feeder 124 may spray gas toward the third side gas feeder 125. At this time, if a tangent line is formed at a location where the circular housing 110 contacts the side gas feeder 120, an angle formed by the tangent line and the direction in which the gas is sprayed from the side gas feeder 120 may be 22.5 degrees.

[0104] In order to make the gas ejected from the second side gas feeder 124 receive force from the third side gas feeder 125, the angle formed by the tangent line and the direction in which the gas is ejected from the second side gas feeder 124 is preferably greater than 22.5 degrees.

[0105] Since the number of the side gas feeders 120 provided in the shell 110 is preferably less than 8, when a tangent is formed at a location where the shell 110 formed in a circular shape contacts the side gas feeder 120, an angle formed by the tangent and the direction in which the gas is ejected from the side gas feeder 120 is preferably greater than 22.5 degrees, and preferably greater than 20 degrees.

[0106] In addition, when the three side gas feeders 120 are provided in the shell 110, the angle formed by the line connecting the second side gas feeder 124 to the first side gas feeder 123 and the line connecting the second side gas feeder 124 to the third side gas feeder 125 can be 60 degrees.

[0107] At this time, if a tangent line is formed at a point where the circular housing 110 contacts the second side gas feeder 124 , an angle formed by the tangent line and a direction in which gas is ejected from the second side gas feeder 124 may be 60 degrees.

[0108] Since the number of the side gas feeders 120 provided in the shell 110 is preferably 3 or more, when a tangent is formed at a location where the shell 110 formed in a circular shape contacts the side gas feeder 120, an angle formed by the tangent and the direction in which the gas is ejected from the side gas feeder 120 is preferably less than 60 degrees.

[0109] The plasma chamber having the side gas feeder for forming a vortex motion according to the embodiment of the present invention may further include a central gas feeder 130 provided on the upper portion of the housing 110 and injecting gas into the housing 110 .

[0110] When the gas injected into the plasma chamber is composed of heavy molecules, if only the central gas feeder is used, the velocity in the z direction (the lower direction of the housing) increases due to the heavy molecules, which causes a problem of poor etching rate uniformity.

[0111] The plasma chamber with the side gas feeder according to the embodiment of the present invention uses the side gas feeder 120 together with the central gas feeder 130 and adjusts the design of the side gas feeder 120 to prevent the etching rate uniformity from being deteriorated.

[0112] When the central gas feeder 130 and the side gas feeder 120 are used simultaneously, the side gas feeder 120 is preferably provided between the seating portion 111 of the housing 110 and the central gas feeder 130 provided on the upper portion of the housing 110 .

[0113] According to an embodiment of the present invention, the plasma formed in the reaction space of the housing 110 includes ions and free radicals, and the wafer 10 may be etched through a synergistic effect of the ions and the free radicals.

[0114] According to an embodiment of the present invention, the plasma formed in the reaction space of the housing 110 includes electrons, and an electron energy relaxation length (EERL) of the electrons may be smaller than a diameter of the housing.

[0115] The plasma chamber with a side gas feeder that forms a vortex motion according to an embodiment of the present invention can be performed in the process field of local electron kinetics. Existing etching processes are performed in the process field of nonlocal electron kinetics, where the electron energy relaxation length (EERL) is always greater than the diameter of the process chamber.

[0116] However, the plasma chamber with a side gas feeder that forms a vortex motion according to an embodiment of the present invention can be used in a local electron dynamics (Local Electron Kinetics) process field where the electron energy relaxation length (EERL) is smaller than the diameter of the process chamber (the diameter of the above-mentioned shell 110).

[0117] Therefore, according to an embodiment of the present invention, the plasma chamber with a side gas feeder that forms a vortex motion can make the plasma density at the edge of the above-mentioned shell 110 higher than the plasma density at the center of the above-mentioned shell 110, and the etching rate at the edge of the above-mentioned shell 110 can also be higher than the etching rate at the center of the above-mentioned shell 110.

[0118] In the conventional etching process, a problem of weak etching execution at the edge of the wafer (low edge yield problem) may occur. However, the plasma chamber with a side gas feeder according to an embodiment of the present invention is formed so that the etching rate at the edge of the shell 110 is higher than the etching rate in the center of the shell 110, thereby preventing the above problem from occurring.

[0119] In addition, in the existing etching process, in order to solve the problem of low edge yield of etching at the edge of the wafer, independent RF power is applied or a heater is used, and a lifting device is used to prevent the edge ring from being eroded (erosion) by plasma.

[0120] However, according to an embodiment of the present invention, the plasma chamber with a side gas feeder that forms a vortex motion is formed so that the etching rate at the edge of the above-mentioned shell 110 is higher than the etching rate in the center of the above-mentioned shell 110, so that a separate device is not needed, thereby having the advantage of reducing production costs while expecting to increase profitability.

[0121] According to an embodiment of the present invention, a plasma chamber with a side gas feeder that forms a vortex motion can be carried out in the process field of Local Electron Kinetics, so that the plasma density inside the shell 110 gradually increases from the inside of the shell 110 toward the outside of the shell 110.

[0122] Thus, a concave etch rate profile can be obtained in which the etch rate is low inside the housing 110 and the etch rate gradually increases toward the outside of the housing 110. The concave etch rate profile can solve the problem of low edge yield at the edge of the housing 110.

[0123] However, a concave etch rate profile cannot be obtained if the heavy molecule gas is injected only through the central gas feeder 130. That is, if the heavy molecule gas is injected from the central gas feeder 130 in the presence of the heavy molecule gas, the process field of Local Electron Kinetics may be invalid.

[0124] In order to solve this problem, the plasma chamber provided with the side gas feeder that forms a vortex motion according to an embodiment of the present invention may inject a gas of heavy molecules from the side gas feeder 120 .

[0125] According to an embodiment of the present invention, the gas injected from the side gas feeder 120 may have a molecular weight heavier than that of the gas injected from the central gas feeder 130. If the gas with heavy molecules is injected from the central gas feeder 130, the uniformity of the etching rate cannot be improved. Therefore, the gas with heavy molecules is preferably injected through the side gas feeder 120.

[0126] Specifically, the heavy molecule gas may form a downward swirl motion while being injected from the side gas feeder 120 , thereby improving the uniformity of the etching rate.

[0127] Here, although the gas injected from the side gas feeder 120 may have a molecular weight heavier than that of the gas injected from the center gas feeder 130, a portion of the gas injected from the side gas feeder 120 may not be heavier than that of the gas injected from the center gas feeder 130, or may be the same gas as the gas injected from the center gas feeder 130.

[0128] That is, the gas of heavy molecules is injected only through the side gas feeder 120 , and general gas other than the gas of heavy molecules can be injected through the side gas feeder 120 and the central gas feeder 130 .

[0129] According to an embodiment of the present invention, the side gas feeder 120 includes a nozzle 121 having a nozzle hole 122 for injecting gas, and a plurality of the side gas feeders 120 may be provided in the housing 110 .

[0130] According to an embodiment of the present invention, if the radius of the swirl motion formed by the gas injected from the side gas feeder 120 is adjusted in consideration of the gas injected from the central gas feeder 130 , it is possible to affect the plasma density distribution.

[0131] Specifically, the plasma density distribution of the concave etch rate profile may be adjusted by adjusting the radius of the swirl motion formed by the gas injected from the side gas feeder 120 .

[0132] As described above, the plasma chamber with a side gas feeder that forms a vortex motion according to an embodiment of the present invention can obtain a concave etch rate profile in which the etch rate is low inside the shell 110 and the etch rate gradually increases toward the outside of the shell 110.

[0133] The concave etch rate profile can be obtained by adjusting the pressure inside the housing 110. According to an embodiment of the present invention, if the radius of the swirl motion formed by the gas ejected from the side gas feeder 120 is adjusted in addition to adjusting the factors related to the pressure, the plasma density distribution in the concave etch rate profile can also be adjusted.

[0134] According to an embodiment of the present invention, the side gas feeder 120 includes a nozzle 121 having a nozzle hole 122 for injecting gas, and a plurality of the side gas feeders 120 may be provided in the housing 110 .

[0135] The plurality of side gas feeders 120 may be provided at the upper portion, the middle portion, or the lower portion of the shell 110 . The plurality of side gas feeders 120 may also be provided at any one of the upper portion, the middle portion, or the lower portion of the shell 110 .

[0136] According to an embodiment of the present invention, when the side gas feeder 120 is provided at the lower portion of the housing 110, although the uniformity of the etching rate can be improved, when the side gas feeder 120 is provided at the lower portion of the housing 110, the etching rate may not be effectively improved. Therefore, the plurality of side gas feeders 120 according to an embodiment of the present invention are preferably disposed at appropriate positions of the upper portion, the middle portion, and the lower portion of the housing 110.

[0137] Reference Figure 3 Each nozzle 121 of the side gas feeder 120 may be provided with a plurality of the nozzle holes 122. The plurality of nozzle holes 122 provided in the nozzle 121 may have the same size or different sizes.

[0138] According to an embodiment of the present invention, the nozzle hole 122 is preferably formed in a circular shape with a diameter of 0.1 to 1 mm. In the case where the diameter of the nozzle hole 122 is greater than 1 mm, arcing may occur, so in order to prevent this phenomenon, the diameter of the nozzle hole 122 is preferably less than 1 mm. In addition, in order to effectively spray gas through the nozzle hole 122, the diameter of the nozzle hole 122 is preferably greater than 0.1 mm.

[0139] According to an embodiment of the present invention, the gas injected from the side gas feeder 120 may form a downward swirl motion in the housing 110 and be injected toward the wafer 10. At this time, the gas injected from the side gas feeder 120 may rotate in a clockwise direction or a counterclockwise direction and form a downward swirl motion.

[0140] The plasma chamber with the side gas feeder according to the embodiment of the present invention uses the side gas feeder 120 in an inductively coupled plasma (ICP), and the gas injected from the side gas feeder 120 can form a downward swirl motion.

[0141] The gas injected from the side gas feeder 120 forms a downward swirl motion. The plasma chamber with a side gas feeder according to an embodiment of the present invention can be applied to metal etching, oxide etching, polysilicon etching and improve the etching rate.

[0142] In addition, the side gas feeder 120 that injects gas in a downward swirl motion may also be applicable to plasma processes such as plasma deposition, PR stripping, and plasma doping.

[0143] The plasma chamber provided with the side gas feeder that forms a vortex motion according to the embodiment of the present invention described above has the following effects.

[0144] The plasma chamber according to the embodiment of the present invention described above is equipped with a side gas feeder that forms a swirl motion. The injection direction of the gas injected from the side gas feeder is adjusted toward the wall of the shell, so that the gas injected from the nozzle forms a swirl motion in the chamber, thereby having the advantage of being able to maintain a uniform etching rate inside the chamber.

[0145] In addition, according to an embodiment of the present invention, a plasma chamber having a side gas feeder that forms a swirl motion adjusts the direction of gas ejected from a side gas feeder provided in a shell to a direction toward another side gas feeder adjacent to the side gas feeder, so that the gas ejected from the nozzle can form a swirl motion in the chamber, thereby having the advantage of being able to maintain a uniform etching rate inside the chamber.

[0146] In addition, according to an embodiment of the present invention, a plasma chamber having a side gas feeder that forms a vortex motion is formed so that the injection direction of the gas injected from the side gas feeder is adjusted toward the wall surface of the shell and the speed or flow rate of the gas injected from one side gas feeder can reach another adjacent side gas feeder, thereby having the advantage of being able to prevent the gas injected from the side gas feeder from hitting the wall surface of the shell.

[0147] In addition, according to an embodiment of the present invention, a plasma chamber having a side gas feeder that forms a swirl motion is formed so that the speed or flow rate of the gas ejected from one side gas feeder can reach another adjacent side gas feeder, thereby having the advantage that the gas ejected from one side gas feeder can be subjected to force from the other side gas feeder to form a swirl motion.

[0148] At the same time, according to an embodiment of the present invention, a plasma chamber with a side gas feeder that forms a vortex motion uses a side gas feeder and a central gas feeder in the chamber at the same time, and a heavy molecular gas is injected through the side gas feeder, thereby having the advantages of being able to improve the uniformity of the etching rate and being able to improve the etching rate.

[0149] According to an embodiment of the present invention, a plasma chamber with a side gas feeder that forms a swirl motion forms a swirl motion, thereby obtaining an effect similar to that of using a confinement ring or an electromagnet. The process using the confinement ring plays a role in directly controlling the space in which the process is performed, thereby also expecting enhancement of plasma density and edge etch rate.

[0150] The process of using electromagnets is to arrange electromagnets around the chamber, and the flow of electrons to the shell wall can be controlled by arranging electromagnets around the chamber.

[0151] The plasma chamber provided with the side gas feeder for forming a swirl motion according to the embodiment of the present invention forms a swirl motion, and thus has an advantage of being able to obtain an effect similar to that of using a confinement ring or an electromagnet.

[0152] In addition, the plasma chamber with a side gas feeder that forms a vortex motion according to an embodiment of the present invention can effectively improve the uniformity of the etching rate when performing metal etching or oxide etching, and increase the number of side gas feeders, thereby having the advantage of also being able to contribute to the density of free radicals and ions.

[0153] Thus, although the present invention has been described with reference to one embodiment illustrated in the accompanying drawings, this is merely illustrative, and those skilled in the art will appreciate that various modifications and variations of the embodiment are possible. Therefore, the true technical protection scope of the present invention should be determined by the technical ideas of the appended claims.

Claims

1. A plasma chamber with a side gas feeder that forms a vortex motion, the plasma chamber being a plasma chamber for forming plasma for etching a wafer, wherein the plasma chamber with a side gas feeder that forms a vortex motion is characterized in that it comprises: A housing having a placement portion for placing the wafer; as well as, a side gas feeder provided on a side of the housing and injecting gas into the interior of the housing, The housing is provided with a plurality of the side gas feeders. The side gas feeder includes a nozzle having a nozzle hole for injecting gas, The side gas feeder injects gas toward a wall surface of the housing.

2. The plasma chamber with a side gas feeder for forming a vortex motion according to claim 1, characterized in that: The plurality of side gas feeders provided in the housing are provided at positions having the same height from the placement portion.

3. The plasma chamber with a side gas feeder for forming a vortex motion according to claim 2, characterized in that: The direction of the gas ejected from the side gas feeder is a direction on a plane extending in parallel with a plane formed by the seating portion on which the wafer is seated.

4. The plasma chamber with a side gas feeder for forming a vortex motion according to claim 2, characterized in that: When any one of the plurality of side gas feeders provided in the housing is referred to as a first side gas feeder, and a side gas feeder adjacent to the first side gas feeder is referred to as a second side gas feeder, The first-side gas feeder sprays gas toward the second-side gas feeder.

5. The plasma chamber with a side gas feeder for forming a vortex motion according to claim 2, characterized in that: When any one of the plurality of side gas feeders provided in the housing is referred to as a first side gas feeder, the side gas feeder adjacent to the first side gas feeder is referred to as a second side gas feeder, and the side gas feeder adjacent to the second side gas feeder in the opposite direction to the direction in which the first side gas feeder is adjacent is referred to as a third side gas feeder, The first-side gas feeder sprays gas in a direction between the second-side gas feeder and the third-side gas feeder.

6. The plasma chamber with a side gas feeder for forming a vortex motion according to claim 2, characterized in that: The housing is provided with n side gas feeders, wherein n is a natural number greater than or equal to 3, and n is the number of the side gas feeders.

7. The plasma chamber with a side gas feeder for forming a vortex motion according to claim 2, characterized in that: The plurality of side gas feeders provided in the housing are provided in the housing in the form of a regular polygon.

8. The plasma chamber with a side gas feeder for forming a vortex motion according to claim 2, characterized in that: When the number of the side gas feeders provided at the same height from the placement portion is referred to as n, The angle formed by one of the side gas feeders and two adjacent side gas feeders on both sides of the side gas feeder is 180×(n-2) / n degrees, wherein n≥3.

9. The plasma chamber with a side gas feeder for forming a vortex motion according to claim 1, characterized in that: The invention further includes a central gas feeder provided on the upper portion of the housing and configured to inject gas into the interior of the housing.

10. The plasma chamber with a side gas feeder for forming a vortex motion according to claim 9, characterized in that: The gas injected from the side gas feeder is a gas having a heavier molecular weight than the gas injected from the center gas feeder.

11. The plasma chamber with a side gas feeder for forming a vortex motion according to claim 1, characterized in that: The plasma formed in the inner space of the housing contains ions and free radicals. The wafer is etched by a synergy effect of the ions and the radicals.

12. The plasma chamber with a side gas feeder for forming a vortex motion according to claim 1, characterized in that: The above-mentioned nozzle hole is formed in a circular shape having a diameter of 0.1 to 1 mm.

13. The plasma chamber with a side gas feeder for forming a vortex motion according to claim 1, characterized in that: The side gas feeder provided in the housing includes a controller for adjusting a flow rate or a speed of the gas ejected from the side gas feeder.

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