JP2023509261A - Plasma processing system with openable Faraday assembly and openable Faraday assembly - Google Patents

Abstract

The present invention provides an openable Faraday assembly and a plasma processing system having an openable Faraday assembly. The openable Faraday assembly has a Faraday layer including a rotary button, a radio frequency access block, a lifting mechanism, and a plurality of annular fan blades, each annular fan blade driven by the rotary button to a corresponding fan surface. and the amplitude of rotation can be adjusted between the first and second limit positions by the guide connection between the second positioning member and the guide slide groove of the rotary button. When each annular fan blade is positioned at a first limit position, the Faraday layer is in a closed state, and when each annular fan blade is positioned at a second limit position, the Faraday layer is open. state, in which the central area inside the rotate button is fully exposed. Therefore, according to the present invention, by controlling the opening and closing of the Faraday layer, the etching and cleaning steps can be performed together to achieve complete cleaning of the coupling window, and even if the Faraday layer is open during the etching step, the etching process can be performed. It does not affect the process at all. [Selection drawing] Fig. 1

Description

The present invention is in the technical field of semiconductor integrated circuit manufacturing and relates to plasma processing systems, and more particularly to plasma processing systems having open and close Faraday cleaning assemblies.

Etching is one of the most important processes in the manufacturing process of semiconductor integrated circuits, and plasma etching is one of the commonly used etching methods. Etching is usually performed in a vacuum reaction chamber, which includes an electrostatic chuck used for chucking the wafer and RF load, cooling the wafer, and the like. Currently, in the manufacturing process of semiconductor devices, an electrostatic chuck is usually placed at the base of the center of the vacuum processing chamber, and the wafer is placed on the upper surface of the electrostatic chuck. Then, by applying a high frequency to the electrode above the base, a plasma of the introduced reactive gas is generated within the processing chamber to process the wafer.

Currently, in the etching process of some non-volatile metal materials, the plasma is accelerated under the action of a bias voltage to reach the surface of the metal material, and the metal particles sputtered from the surface of the etched material are deposited in the chamber. It contributes to contamination of all exposed surfaces, including interior walls and upper tie-down windows. Therefore, in order to deal with the contamination, it is necessary to introduce a cleaning gas into the chamber and apply high frequency power to the top to ionize the cleaning gas and carry away these contaminating particles. During the entire cleaning process, the chamber is grounded and the upper coupling window is made of insulating material, so that when high frequency power is applied to the top of the cleaning process to excite the plasma, the activated plasma will pass through the grounded chamber. It cleans, but has little cleaning effect on the binding window. Over time, the contaminants build up and thicken, eventually causing the deposits to fall off and contaminate the wafer.

A Faraday layer can be used to thoroughly clean the coupling window. In plasma processing chambers, the use of a Faraday shield can reduce the erosion of chamber materials by the plasma, but some plasma can pass through the gaps between the Faraday layers and contaminate the coupling window. Placing a Faraday layer between the rf coil and the coupling window can reduce erosion of the walls of the chamber by ions induced by the rf electric field. Such shields can be grounded or floating. If the Faraday shield is grounded, the high frequency electric field strength is reduced due to reduced capacitive coupling, making it very difficult to induce a plasma discharge. Also, if the plasma is a floating design, plasma excitation is not overly impeded, but is less effective at preventing plasma encroachment into the chamber.

The present invention has been made in view of the problems in the prior art, which can effectively avoid adverse effects on wafer etching and can achieve complete cleaning of the bonding window by using a Faraday layer during cleaning of the bonding window. The purpose is to provide a Faraday assembly. The openable Faraday assembly is disposed outside the coupling window of the plasma processing system, and during cleaning, each annular fan blade constituting the openable Faraday assembly is in a closed state, and the contact area between the coupling window and the plasma can be covered. In this case, the inner arc surface of each annular fan blade is arranged on the concentric circle a, and the outer arc surface of each annular fan blade is arranged on the concentric circle b. On the other hand, during etching, each annular fan blade that constitutes the retractable Faraday assembly is in an open state to fully expose the central coil in the retractable Faraday assembly. In this case, the first cross section of each annular fan blade can all touch the inscribed circle of the maximum opening, the diameter of the inscribed circle of the maximum opening being greater than the outer diameter of the central coil.

In order to achieve the above objects, the openable Faraday assembly according to the present invention comprises a rotary button, a high frequency access block, an elevating mechanism for driving the high frequency access block, and evenly distributed outside an O-axis, respectively. a Faraday layer comprising a plurality of annular fan blades provided;
The rotary button has a circular ring shape as a whole, and is concentrically rotatably provided on the outer side of the O axis, and the same number of guide slide grooves as the annular fan blades are formed along the annular surface of the rotary button, etc. provided at intervals,
Each of the annular fan blades includes an inner arcuate surface, an outer arcuate surface, and a first side molding surface and a second side molding surface connecting side surfaces on the same side of the inner arcuate surface and the outer arcuate surface, respectively; A first positioning member and a second positioning member are provided on the fan surface near the outer arc surface of the annular fan blade,
Each of said annular fan blades can be driven by said rotation button to rotate synchronously around a first positioning member provided on the corresponding fan surface, and the rotation amplitude is controlled by said second positioning member and the guide of said rotation button. delimited between a first limit position and a second limit position by a guide connection between the slide groove;
When each of the annular fan blades is positioned at the first limit position, the Faraday layer is in a closed state, in which case the inner arcuate surface of each of the annular fan blades is aligned with the outer concentric circle a of the O-axis. The outer arcuate surfaces of the annular fan blades are equally spaced on the circumference of the concentric circle b outside the O-axis, and the inner diameter of the concentric circle a is equal to that of the concentric circle b. smaller than the inner diameter,
When each of the annular fan blades is positioned at the second limit position, the Faraday layer is in an open state, in which case the first side forming surface of each of the annular fan blades is aligned with the inscribed circle of the maximum opening. can fully expose the area corresponding to the maximum opening inscribed circle inside the rotary button,
the radio frequency access block is connected to the power output of the lifting mechanism;
The elevating mechanism allows the RF access block to move toward the Faraday layer to be conductively connected to the inner arcuate surface of each annular fan blade of the closed Faraday layer; It can be separated from the Faraday layer in an open state away from the layer.

Furthermore, the guide slide groove is a band-shaped groove.

Furthermore, the guide slide groove is provided at an angle.

Further, the first side molding surface and the second side molding surface are both flat molding surfaces, or the first side molding surface is an outwardly curved molding surface and the second side molding surface is an inwardly curved molding surface. It is a molded surface with

Further, the lifting mechanism includes an air cylinder, an air cylinder transfer plate and an air cylinder transfer insulation rod, and the output end of the air cylinder sequentially passes through the air cylinder transfer plate and the air cylinder transfer insulation rod to the high frequency Fixed to the access block.

Further, both the first positioning member and the second positioning member are pins.

Another object of the present invention is to provide a plasma processing system including a coupling window with the openable Faraday assembly outside thereof,
each annular fan blade is connected at a defined position with the coupling window via a first positioning member provided on the corresponding fan surface;
The coupling window is provided with a rotation positioning surface at a position corresponding to the outer edge of the rotation button, and the rotation positioning surface allows the rotation button to rotate about the O-axis.

Furthermore, the outer side of the openable Faraday assembly is provided with a coil structure including a central coil, the central coil is orthographically projected to the inner region of the rotary button, the outer diameter of the central coil is the inscribed circle of the maximum opening. is less than or equal to the diameter of
When each annular fan blade is positioned at the first limit position, the inner arcuate surface of each annular fan blade in the closed state is connected to a Faraday high frequency power supply through a high frequency access block;
When each annular fan blade is positioned at the second limit position, the central coil is completely exposed on the surface of the coupling window, and both the central coil and the edge coil are connected to a coil high frequency power supply.

Further, the coil structure further includes an edge coil provided independently from the central coil, the edge coil being orthographically projected onto an inner region of the rotary button;
When each annular fan blade is positioned at the second limit position, both the central coil and the edge coil are completely exposed on the surface of the coupling window and both are connected to the coil high frequency power supply.

Further, the first positioning member is a first pin, the coupling window is provided with a pinhole at a position corresponding to the first pin of each of the annular fan blades, and each of the annular fan blades is located on the respective fan surface. connected one-to-one with each pinhole in the coupling window by a first pin provided in the
A central fixed hole is provided in the central portion of the coupling window, the central fixed hole is provided with a ceramic inlet port, and the outlet portion of the ceramic inlet port is provided with a nozzle.

further comprising a reaction chamber, the upper end of the reaction chamber is open, the opening of the reaction chamber is hermetically connected to a chamber cover, and a window corresponding to the coupling window is provided in the center of the chamber cover;
a base is provided in the reaction chamber, the upper surface of the base is fixedly connected to a bias electrode facing the nozzle, and a wafer is attached to the upper surface of the bias electrode;
A shield box having a U-shaped cross section is fixed to the upper part of the reaction chamber, and the shield box and the chamber cover are hermetically connected,
The high-frequency access block and the lifting mechanism are both arranged in a shield box, one end of the lifting mechanism is fixed to the top of the shield box, and the other end is fixed to the high-frequency access block.

Yet another object of the present invention is to provide a method based on a plasma processing system having an openable Faraday assembly, the method comprising a coupled window cleaning step and a wafer etching step,
The wafer etching step includes
(1.1) placing a wafer in a reaction chamber over a bias electrode;
(1.2) moving the air cylinder upward to separate the high frequency access block and the Faraday layer;
(1.3) By rotating the rotary button, the Faraday layer is opened to the second limit position, and in this case, the first side forming surface of each annular fan blade constituting the Faraday layer is in contact with the inscribed circle of the maximum opening. so that the central coil facing the inscribed circle of the largest aperture directly faces the coupling window;
(1.4) introducing a process gas into the reaction chamber through a ceramic inlet port and supplying a demanding high frequency power supply to the central coil;
(1.5) plasma etching at the surface of the wafer;
(1.6) when the etching process is finished, stopping the introduction of the process gas into the reaction chamber and the power supply to the central coil, and evacuating the reaction chamber;
including
The binding window cleaning step includes:
(2.1) placing a substrate over a bias electrode in the reaction chamber;
(2.2) The Faraday layer is closed by rotating the rotation button, in which case the inner arcuate surface of each annular fan blade is positioned on the circumference of the concentric circle a outside the O-axis, and each annular the outer arc surface of the fan blade is located on the circumference of the concentric circle b outside the O axis;
(2.3) By lowering the air cylinder and strongly pressing the high-frequency access block against the portion of the closed Faraday layer near the inner arcuate surface of each annular fan blade, the high-frequency access block conducts electricity to each annular fan blade. and
(2.4) introducing a cleaning gas into the reaction chamber through a ceramic inlet port;
(2.5) supplying a high frequency power supply to meet the requirements of the Faraday layer through the high frequency access block;
(2.6) after the cleaning is completed, stopping the introduction of the cleaning gas into the reaction chamber and the power supply to the Faraday layer, and evacuating the reaction chamber;
including.

ADVANTAGE OF THE INVENTION According to this invention, there exist the following beneficial effects compared with a prior art.
The openable Faraday assembly according to the present invention is arranged outside the coupling window of the plasma processing system, and when cleaning, each annular fan blade constituting the openable Faraday assembly is in a closed state, and the coupling window and the plasma are in a closed state. The contact area can be covered. In this case, the inner arcuate surface of each annular fan blade is positioned on the concentric circle a, and the outer arcuate surface of each annular fan blade is positioned on the concentric circle b. On the other hand, during etching, the annular fan blades that make up the retractable Faraday assembly are in an open state, allowing the central coil of the retractable Faraday assembly to be fully exposed. In this case, the first cross section of each annular fan blade can all be tangent to the inscribed circle of the largest opening, the diameter of the inscribed circle of the largest opening being greater than the outer diameter of the central coil. Therefore, the openable Faraday assembly according to the present invention can effectively avoid adverse effects on wafer etching, and furthermore, can achieve complete cleaning of the coupling window by using the Faraday layer during cleaning of the coupling window. That is, according to the present invention, it is possible to solve the problem of the reduction in the strength of the high-frequency electric field caused by the conventional Faraday shield unit, to facilitate cleaning of the coupling window without affecting the strength of the high-frequency electric field, and to facilitate the operation. Is possible.

1 illustrates a plasma processing system having an openable Faraday assembly; FIG. 2 is a diagram showing a schematic structure of a coupling window in FIG. 1; FIG. Fig. 2 shows a schematic structure of the openable Faraday assembly of Fig. 1 in a closed state; Fig. 4 shows the schematic structure of the openable Faraday assembly of Fig. 3 in an open state; 4 is a diagram showing a schematic structure of a fan (fan-shaped) blade in FIG. 3; FIG. 1 is a flowchart of a method based plasma processing system having an openable Faraday assembly according to the present invention;

The following clearly and completely describes the technical solutions according to the embodiments of the present invention with reference to the drawings. Of course, the embodiments described below are only some, but not all embodiments of the present invention. The at least one exemplary embodiment described below is merely illustrative and does not constitute any limitation to the invention and its application or use. Other embodiments obtained by so-called persons skilled in the art without creative efforts based on the embodiments of the present invention shall all fall within the protection scope of the present invention. Unless otherwise stated, the relative arrangements, expressions and numerical values of the components and steps of the embodiments described below are not intended to limit the scope of the invention. Additionally, it should be understood that, for clarity of illustration, the dimensions of the various parts shown in the drawings are not drawn according to actual scale and relationship. Techniques, methods and apparatus well known to those of ordinary skill in the relevant arts will not be described in detail, but these techniques, methods and apparatus should be considered part of this specification if necessary. is. In all embodiments shown and discussed herein, any specific values are exemplary and non-limiting. Accordingly, other embodiments that differ from the exemplary embodiment may have different values.

For clarity of explanation, spatially relative terms such as "above", "top", "top surface", "top surface" are used to distinguish between one device or technical feature shown in the drawings and another device or technical feature. Spatial relationships between features may also be described. It should be understood that spatially relative terms are intended to encompass different orientations of the device in use or operation other than that shown in the drawings. For example, if a device in a drawing is inverted, a device described as "above another device or structure" or "above another device or structure" may then be referred to as "below another device or structure" or It will be positioned as "underneath another device or structure." Thus, the exemplary term "above" can include the two orientations "above" and "below." Also, the positioning may be done in other ways (rotated 90 degrees or in other directions).

The openable Faraday assembly 14 according to the present invention has a Faraday layer, which, as shown in FIGS. and a plurality of annular fan blades 14-1 evenly distributed outside the O-axis and provided respectively. The material of the fan blades is preferably copper or aluminum. Here, the rotary button 10 has a circular ring shape as a whole, and is concentrically rotatably provided on the outer side of the O-axis. are provided at equal intervals along the In the figure, the guide slide grooves 11 are evenly provided centrally symmetrically about the O-axis on the annular surface of the rotary button 10, and the center line is the inscribed circle of the maximum opening formed when the Faraday layer is opened. touches (becomes tangent to) The material of the rotary button 10 is preferably the insulating material ULTEM-1000. is a rotation positioning surface 8 provided on the edge of the . The rotary button 10 may be manually operated, but may be driven by an external electrode or an external rotary air cylinder 19, and is not limited in the present invention.

Each annular fan blade 14-1 has a first side connecting the inner arcuate surface 14-lb, the outer arcuate surface 14-1d, and the side surfaces on the same side of the inner arcuate surface 14-lb and the outer arcuate surface 14-1d, respectively. a molding surface 14-la and a second side molding surface 14-lc. Different shaped annular fan blades 14-1 may be used to form different shaped Faraday layers. That is, the first side molding surface 14-la and the second side molding surface 14-lc have the shape shown in FIG. Molding surface 14-lc may be an inwardly curved molding surface, or both may be flat molding surfaces. Furthermore, a first positioning member and a second positioning member are provided on the fan surface in the vicinity of the outer peripheral arcuate surface 14-1d of each annular fan blade 14-1. The first positioning member and the second positioning member are both pins, the first pin 12 and the second pin 13 respectively.

Each annular fan blade 14-1 can be driven by the rotation button 10 to rotate synchronously around the first positioning member provided on the corresponding fan surface, and its rotation amplitude can be controlled by the second positioning member and the guide of the rotation button 10. It is delimited between a first limit position and a second limit position by a guiding connection with the slide groove 11 . In the present invention, the guide slide groove 11 is a strip-shaped groove and is provided at an angle.

When each annular fan blade 14-1 is positioned at the first limit position, the Faraday layer is closed. In this case, the inner arcuate surface 14-lb of each annular fan blade 14-1 is arranged at equal intervals on the outer concentric circle a of the O-axis, and the outer arcuate surface 14-lb of each annular fan blade 14-1 ld are arranged at equal intervals on the circumference of the concentric circle b outside the O axis, and the inner diameter of the concentric circle a is smaller than that of the concentric circle b.

When each annular fan blade 14-1 is positioned at the second limit position, the Faraday layer is open. In this case, the first side forming surface 14-1a of each annular fan blade 14-1 is all in contact with (is tangent to) the inscribed circle of the maximum opening and corresponds to the maximum opening inscribed circle inside the rotary button 10. fully exposed areas.

A radio frequency access block 22 is connected to the power output of the lifting mechanism. In the present invention, the lifting mechanism includes air cylinder 19 , air cylinder transfer plate 20 and air cylinder transfer insulating rod 21 . The power output end of the air cylinder is fixed to the high frequency access block 22 through the air cylinder transfer plate 20 and the air cylinder transfer insulating rod 21 in sequence.

An elevating mechanism allows the RF access block 22 to be moved toward the Faraday layer and conductively connected to the inner arcuate surface 14-lb of each annular fan blade 14-1 of the closed Faraday layer, or the RF access block. 22 can be separated from the Faraday layer in an open state away from the Faraday layer.

By using the openable Faraday assembly 14 in a plasma processing system, a plasma processing system having the openable Faraday assembly 14 including the coupling window 7 is obtained. In the present invention, the material of the coupling window 7 is usually ceramic, located directly above the reaction chamber 1 and the chamber cover 6, and the gas inlet nozzle 9 is provided in the center through a central fixing hole. ing. The nozzle is provided at the outlet portion of a ceramic inlet port 16 for supplying process/clean gas to the chamber during the process step. A bias electrode 4 and a wafer 5 positioned directly above the bias electrode 4 are placed in the reaction chamber 1 . A coil structure is provided above the coupling window 7 , which coil structure is a three-dimensional coil 17 . The three-dimensional coil 17 includes two independent parts, the central coil and the edge coils. Both the central coil and the edge coil are formed by combining two single-dimensional coils, and each single-dimensional coil is provided in two, three, or more stages in the vertical direction, and two coils on the plane. Wrapped in rolls, 3 rolls or more. One ends of the two single-dimensional coils are both connected to an external high-frequency device, and the other ends are both grounded. The openable Faraday assembly 14 is positioned in an intermediate layer between the coupling window 7 and the three-dimensional coil 17 . In this case, each annular fan blade 14-1 is connected at a defined position with the coupling window 7 via a first positioning member provided on the corresponding fan surface. The coupling window 7 is provided with a rotation positioning surface 8 at a position corresponding to the outer edge of the rotation button 10. By positioning the rotation positioning surface 8, the rotation button 10 can rotate about the O-axis. The three-dimensional coil 17 is orthographically projected onto the inner region of the rotary button 10, and the outer diameter of the three-dimensional coil 17 is less than or equal to the diameter of the inscribed circle of the maximum opening. That is, both the central coil and the edge coil can be orthographically projected onto the outer peripheral area of the rotary button 10, and the outer diameter of the edge coil is less than or equal to the diameter of the inscribed circle of the maximum opening.

When each annular fan blade 14-1 is positioned at the first limit position, the inner arcuate surface 14-lb of each annular fan blade 14-1 in the closed state is connected to the Faraday RF power supply through the RF access block 22. be done.

When each annular fan blade 14-1 is positioned at the second limit position, the three-dimensional coil 17 is completely exposed on the surface of the coupling window 7, and both the center coil and the edge coil are connected to the coil high frequency power supply.

The first positioning member is the first pin 12, and the coupling window 7 is provided with a pinhole 15 at a position corresponding to the first pin 12 of each annular fan blade 14-1. A first pin 12 provided on each fan surface is connected to each pinhole 15 in the coupling window 7 one-to-one.

Furthermore, it includes a reaction chamber 1, the upper end of the reaction chamber 1 is open, the opening of the reaction chamber 1 is hermetically connected to the chamber cover 6, and the central position of the chamber cover 6 is provided with a window corresponding to the coupling window 7. ing.

A base 3 is provided in the reaction chamber 1 . The upper surface of the base 3 is fixedly connected to a bias electrode 4 facing the nozzle, and the wafer 5 is attached to the upper surface of the bias electrode 4 .

An insulating member is used to insulate between the openable Faraday assembly 14 above the coupling window 7 and the central coil, and the entire upper high frequency is shielded by a shield box 18 . Further, a high-frequency access block 22 for high-frequency access and an elevating mechanism for the open/close type Faraday assembly 14 are both fixedly arranged in the shield box 18. One end of the elevating mechanism is fixed to the top of the shield box 18, and the other end is fixed. are fixed to the high frequency access block 22 . The lifting mechanism includes an air cylinder, an air cylinder transfer plate 20 and an air cylinder transfer insulating rod 21 . The material of the air cylinder transfer plate 20 is preferably 316L stainless steel, the material of the air cylinder transfer insulation rod 21 is preferably ULTEM-1000, and the air cylinder transfer insulation rod 21 is connected to the air cylinder transfer plate 20 for high frequency access. It provides insulating support to and from block 22, yet leaves sufficient space for gas introduction through the central ceramic port. The material of the high frequency access block 22 is preferably copper or aluminum and is connected to high frequency.

Yet another object of the present invention is to provide a method based on a plasma processing system having an openable Faraday assembly 14 including cleaning of the bonding window 7 and etching of the wafer 5, as shown in FIG. That is.

The etching process of the wafer 5 specifically includes the following steps.
(1.1) Place the wafer 5 above the bias electrode 4 in the reaction chamber 1 .

(1.2) Move the air cylinder upward to separate the high frequency access block 22 and the Faraday layer.

(1.3) Open the Faraday layer to the second limit position by rotating the rotary button 10 . In this case, the first side forming surface 14-la of each annular fan blade 14-1 constituting the Faraday layer can all contact the inscribed circle of the maximum opening, and the central coil facing the inscribed circle of the maximum opening directly faces (opposes) the coupling window 7 .

(1.4) Introduce the process gas into the reaction chamber 1 through the ceramic inlet port 16 and supply the central coil with a high frequency power supply that meets the requirements.

(1.5) Plasma etching is performed on the surface of the wafer 5 .

(1.6) After the etching process is completed, the introduction of the process gas into the reaction chamber 1 and the power supply to the central coil are stopped, and the reaction chamber 1 is evacuated.

After the wafer 5 has been etched, the Faraday layer is open.

After the etching process of the wafer 5, the cleaning process of the bonding window 7 needs to be performed, specifically including the following steps.
(2.1) Place the substrate above the bias electrode 4 in the reaction chamber 1 .

(2.2) The rotary button 10 is positioned by the rotary positioning surface 8 on the coupling window 7 and rotated clockwise about the O-axis so that the guide slide groove 11 on the rotary button 10 is aligned with the annular fan blade 14-1. The second pin 13 rotates, the second pin 13 controls the rotation of the annular fan blade 14-1 with respect to the first pin 12, and the first pin 12 and the pinhole 15 in the coupling window 7 are fitted. The Faraday layer is brought into a closed state by interlocking rotation. In this case, the inner arcuate surface 14-lb of the annular fan blade 14-1 is located on the circumference of the concentric circle a outside the O-axis, and the outer arcuate surface 14-ld of the annular fan blade 14-1 is located on the O-axis. Located on the circumference of the outer concentric circle b.

(2.3) By lowering the air cylinder and lowering the high frequency access block 22 via the air cylinder transfer plate 20 and the air cylinder transfer insulating rod 21, the high frequency access block 22 strongly presses each annular fan blade 14-1. make it press. That is, by strongly pressing the high-frequency access block 22 against the portion near the inner arcuate surface 14-lb of each annular fan blade 14-1 of the Faraday layer in the closed state, the high-frequency access block 22 can move to each annular fan blade 14-1. be conductively connected (conducting) to

(2.4) Introduce cleaning gas into the reaction chamber 1 through the ceramic inlet port 16 .

(2.5) Supply high-frequency power that satisfies the requirements to the Faraday layer via the high-frequency access block 22 .

(2.6) If there is a gap between two adjacent annular fan blades 14-1 after cleaning for a certain period of time, rotate the slit between the two adjacent annular fan blades 14-1 before rotation. The Faraday layer is pushed and rotated at a rotation angle that allows it to be covered by the subsequent annular fan blade 14-1. Thereafter, while maintaining such a state, cleaning is continued for a certain period of time. Through this step, the cleaning of the coupling window 7 can be successfully completed. Conversely, if there is no gap between two adjacent annular fan blades 14-1 and the contact area between the coupling window 7 and the plasma is completely covered, there is no need to push and rotate the Faraday layer.

(2.7) After the cleaning is completed, the introduction of the cleaning gas into the reaction chamber 1 and the power supply to the Faraday layer are stopped, and the reaction chamber 1 is evacuated.

After the cleaning process is finished, the air cylinder is moved upward to move the high frequency access block 22 upward through the air cylinder transfer plate 20 and the air cylinder transfer insulating rod 21, so that the high frequency access block 22 and each annular fan are moved upward. The wing 14-1 is separated. The rotary button 10 rotates counterclockwise around the O-axis through positioning by the rotary positioning surface 8 provided in the coupling window 7, and the guide slide groove 11 provided in the rotary button 10 moves along the annular fan blade 14-1. By rotating the second pin 13, the second pin 13 controls the rotation of the annular fan blade 14-1 around the first pin 12, and the first pin 12 and the pinhole 15 of the coupling window 7 are fitted. By inserting and interlocking and rotating, the Faraday layer is opened. In this case the central coil is not shielded at all, ie the central coil is completely exposed to the coupling window 7 . Thus, the etching process can begin.

The openable Faraday assembly 14 according to the invention can completely or partially cover the contact area between the coupling window 7 and the plasma, thus ensuring complete cleaning. By controlling the opening and closing of the Faraday layer, the etching and cleaning steps can be carried out in unison to achieve complete cleaning of the chamber, especially the coupling window 7 . Furthermore, when the Faraday layer is in the open state, the exciting rf coil is not shielded at all, i.e. the presence of the open and closed Faraday layer does not affect the excitation of the coil and weakens the electric field strength in the case of coil coupling. Therefore, it does not affect the etching process at all.

1 reaction chamber,
2 support arms,
3 base,
4 bias electrode,
5 wafers,
6 chamber cover,
7 coupling window,
7-1 Central fixing hole of coupling window,
8 rotary positioning surface,
9 gas inlet nozzle,
10 rotation button,
11 guide slide groove,
12 first pin,
13 second pin,
14 openable Faraday assembly,
14-1 annular fan blades,
14-1a first side molding surface of the annular fan blade,
14-1b inner arc surface of annular fan blade,
14-1c the second side molding surface of the annular fan blade;
14-1d Outer arc surface of annular fan blade,
15 pinholes,
16 ceramic entry port;
17 three-dimensional coil,
18 shield box,
19 air cylinder,
20 air cylinder transfer plate,
21 air cylinder transfer insulating rod,
22 radio frequency access block,
23 switch box,
24 distribution box.

Claims (12)

a Faraday layer including a rotating button, a radio frequency access block, a lifting mechanism for driving the radio frequency access block, and a plurality of annular fan blades evenly distributed outside the O-axis and respectively provided;
The rotary button has a circular ring shape as a whole, and is concentrically rotatably provided on the outer side of the O axis, and the same number of guide slide grooves as the annular fan blades are formed along the annular surface of the rotary button, etc. provided at intervals,
Each of the annular fan blades includes an inner arcuate surface, an outer arcuate surface, and a first side molding surface and a second side molding surface connecting side surfaces on the same side of the inner arcuate surface and the outer arcuate surface, respectively; A first positioning member and a second positioning member are provided on the fan surface near the outer arc surface of the annular fan blade,
Each of said annular fan blades can be driven by said rotation button to rotate synchronously around a first positioning member provided on the corresponding fan surface, and the rotation amplitude is controlled by said second positioning member and the guide of said rotation button. delimited between a first limit position and a second limit position by a guide connection between the slide groove;
When each of the annular fan blades is positioned at the first limit position, the Faraday layer is in a closed state, in which case the inner arcuate surface of each of the annular fan blades is aligned with the outer concentric circle a of the O-axis. The outer arcuate surfaces of the annular fan blades are equally spaced on the circumference of the concentric circle b outside the O-axis, and the inner diameter of the concentric circle a is equal to that of the concentric circle b. smaller than the inner diameter,
When each of the annular fan blades is positioned at the second limit position, the Faraday layer is in an open state, in which case the first side forming surface of each of the annular fan blades is aligned with the inscribed circle of the maximum opening. can fully expose the area corresponding to the maximum opening inscribed circle inside the rotary button,
the radio frequency access block is connected to the power output of the lifting mechanism;
The elevating mechanism allows the RF access block to move toward the Faraday layer to be conductively connected to the inner arcuate surface of each annular fan blade of the closed Faraday layer; can be separated from the Faraday layer in an open state away from the layer,
Openable Faraday assembly. 2. The openable Faraday assembly according to claim 1, wherein said guide slide groove is a band-shaped groove. 3. The opening and closing type Faraday assembly according to claim 2, wherein the guide slide groove is provided at an angle. Both the first side molding surface and the second side molding surface are flat molding surfaces, or the first side molding surface is an outwardly curved molding surface and the second side molding surface is an inwardly curved molding surface. The openable Faraday assembly according to claim 1, characterized in that it is a plane. The lifting mechanism includes an air cylinder, an air cylinder transfer plate and an air cylinder transfer insulation rod, and the output end of the air cylinder sequentially passes through the air cylinder transfer plate and the air cylinder transfer insulation rod to the high frequency access block. 2. The openable Faraday assembly of claim 1, wherein the openable Faraday assembly is fixed to the . 2. The openable Faraday assembly of claim 1, wherein said first positioning member and said second positioning member are both pins. A plasma processing system comprising a coupling window externally provided with the openable Faraday assembly of claim 1, wherein:
each annular fan blade is connected at a defined position with the coupling window via a first positioning member provided on the corresponding fan surface;
The coupling window is provided with a rotation positioning surface at a position corresponding to the outer edge of the rotation button, and the rotation positioning surface is positioned so that the rotation button can rotate about the O axis.
A plasma processing system having an openable Faraday assembly. A coil structure including a central coil is provided on the outside of the openable Faraday assembly, the central coil is orthographically projected to the inner region of the rotary button, and the outer diameter of the central coil is the diameter of the inscribed circle of the maximum opening and
When each annular fan blade is positioned at the first limit position, the inner arcuate surface of each annular fan blade in the closed state is connected to a Faraday high frequency power supply through a high frequency access block;
when each annular fan blade is positioned at the second limit position, the central coil is completely exposed on the surface of the coupling window, and the central coil and the edge coil are both connected to a coil high frequency power supply;
8. A plasma processing system having an openable Faraday assembly according to claim 7. the coil structure further includes an edge coil provided independently from the central coil, the edge coil being orthographically projected onto an inner region of the rotary button;
When each annular fan blade is positioned at the second limit position, both the central coil and the edge coil are completely exposed on the surface of the coupling window and both are connected to a coil high frequency power supply.
9. A plasma processing system having an openable Faraday assembly according to claim 8. The first positioning member is a first pin, the connecting window is provided with a pinhole at a position corresponding to the first pin of each of the annular fan blades, and each of the annular fan blades is provided on the surface of each fan. connected one-to-one with each pinhole in the coupling window by the first pin connected to the
A central fixing hole is provided in the central part of the coupling window, a ceramic inlet port is provided in the central fixing hole, and a nozzle is provided at the outlet part of the ceramic inlet port.
8. A plasma processing system having an openable Faraday assembly according to claim 7. further comprising a reaction chamber, the upper end of the reaction chamber is open, the opening of the reaction chamber is hermetically connected to a chamber cover, and a window corresponding to the coupling window is provided in the center of the chamber cover;
a base is provided in the reaction chamber, the upper surface of the base is fixedly connected to a bias electrode facing the nozzle, and a wafer is attached to the upper surface of the bias electrode;
A shield box having a U-shaped cross section is fixed to the upper part of the reaction chamber, and the shield box and the chamber cover are hermetically connected,
The high-frequency access block and the elevating mechanism are both arranged in a shield box, one end of the elevating mechanism is fixed to the top of the shield box, and the other end is fixed to the high-frequency access block.
8. A plasma processing system having an openable Faraday assembly according to claim 7. A method based on a plasma processing system having an openable Faraday assembly, the method comprising a coupled window cleaning step and a wafer etching step,
The wafer etching step includes
(1.1) placing a wafer in a reaction chamber over a bias electrode;
(1.2) moving the air cylinder upward to separate the high frequency access block and the Faraday layer;
(1.3) By rotating the rotary button, the Faraday layer is opened to the second limit position, and in this case, the first side forming surface of each annular fan blade constituting the Faraday layer is in contact with the inscribed circle of the maximum opening. so that the central coil facing the inscribed circle of the largest aperture directly faces the coupling window;
(1.4) introducing a process gas into the reaction chamber through a ceramic inlet port and supplying a demanding high frequency power supply to the central coil;
(1.5) plasma etching at the surface of the wafer;
(1.6) when the etching process is finished, stopping the introduction of the process gas into the reaction chamber and the power supply to the central coil, and evacuating the reaction chamber;
including
The binding window cleaning step includes:
(2.1) placing a substrate over a bias electrode in the reaction chamber;
(2.2) The Faraday layer is closed by rotating the rotation button, in which case the inner arcuate surface of each annular fan blade is positioned on the circumference of the concentric circle a outside the O-axis, and each annular the outer arc surface of the fan blade is located on the circumference of the concentric circle b outside the O axis;
(2.3) By lowering the air cylinder and strongly pressing the high-frequency access block against the portion of the closed Faraday layer near the inner arcuate surface of each annular fan blade, the high-frequency access block conducts electricity to each annular fan blade. and
(2.4) introducing a cleaning gas into the reaction chamber through a ceramic inlet port;
(2.5) supplying a high frequency power supply to meet the requirements of the Faraday layer through the high frequency access block;
(2.6) after the cleaning is completed, stopping the introduction of the cleaning gas into the reaction chamber and the power supply to the Faraday layer, and evacuating the reaction chamber;
method including.

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