A new type of ring-shaped adjustable radio frequency coil device

Abstract

The present invention discloses a novel annular adjustable radio frequency coil device, which belongs to the technical field of plasma etcher equipment. The present invention includes a plasma etcher, wherein a chamber is provided inside the plasma etcher, a coil adjustment mechanism is provided inside the chamber, and a radio frequency power supply is installed on one side of the plasma etcher. The coil adjustment mechanism includes a coil body, a protrusion is fixedly installed on the outer periphery of one side of the coil body, a first conductive connection spring is fixedly installed on one end of the protrusion, and a radio frequency coil fixing point is also fixedly installed on the outer periphery of the coil body. The coil body can be provided in multiple groups. The present invention shows a four-group setting. Multiple coil bodies are combined into an annular structure. Gaps are opened between adjacent coil bodies, and coil compensation areas are added outside the incompletely closed areas to compensate for the phenomenon that no electromagnetic field can be formed or a weak electromagnetic field is formed at the gaps.

Description

Technical Field

[0001] The present invention belongs to the technical field of plasma etching equipment, and in particular relates to a novel annular adjustable radio frequency coil device. Background Art

[0002] Inductively coupled plasma etching is a technology that uses chemical and physical processes to selectively remove materials to achieve designed structural patterns.

[0003] The main criteria for evaluating good dry etching technology include mask selectivity, anisotropy, etch rate, overall uniformity, surface smoothness, and lattice damage resistance. However, the most intuitive evaluation indicator is surface topography, including the flatness of the etched bottom and sidewalls, and the anisotropy of the etched mesa. Both of these can be controlled by controlling the ratio of chemical reaction to physical bombardment.

[0004] Mask selectivity is the ratio of the mask's etch depth to the material's etch depth under the same etching conditions and within the same etching time. Generally speaking, a better selectivity results in higher pattern transfer accuracy. However, achieving a good selectivity is not easy. This is because plasma concentrations vary across different areas of the same vacuum chamber. This variation is due to factors such as the fixed, non-adjustable nature of existing designs.

[0005] For example, the RF ring coil adjustment mechanism of the existing plasma etcher has a relatively large gap in the entire coil due to the location of the installation mechanism. Therefore, when coupled glow discharge occurs, the magnetic field generated at the gap is relatively small, which makes it difficult to form plasma of sufficient density in a certain area of the corresponding part. This is why the etching rates of different areas of the wafer vary greatly.

[0006] Moreover, because the position of the RF ring coil adjustment mechanism in the vacuum chamber is completely fixed by ceramic pillars, the magnetic field generated by the coil adjustment mechanism is also fixed. When different gases are introduced, the density of the plasma formed will be highly uncertain due to the different stabilities of the gas molecules themselves. This makes the equipment unsuitable for diversified production, and the process that can be completed is relatively simple.

[0007] Although the change of the lower electrode acceleration bias voltage, namely RF (radio frequency), will have different degrees of influence on the etching rate, it affects the overall etching rate rather than achieving a localized effect. In the end, it will only make the areas with fast etching rates faster and the areas with slow etching rates slightly faster, but it still cannot achieve uniform and flat overall etching, and it is difficult to achieve a better mask selectivity.

[0008] Not only that, the lower electrode acceleration bias voltage, that is, the voltage that RF can withstand, is not infinite, and excessive voltage will also cause varying degrees of damage to the wafer itself. Therefore, if you want to solve the etching rate problem by changing the size of the lower electrode RF, it will have a certain effect on small changes, but if you want to make a very obvious change, it is obviously not advisable.

[0009] Therefore, in terms of existing technology, there is an urgent need for a new device design that can effectively achieve the uniformity of plasma formation and increase the density of plasma, while also achieving adjustable controllability of plasma density and diversified use of equipment, thereby reducing costs and improving production quality and speed. Summary of the Invention

[0010] In response to the above-mentioned problems existing in the prior art, the purpose of the present invention is to provide a novel annular adjustable radio frequency coil device to solve the problems of electromagnetic field unevenness, insufficient plasma density, insufficient plasma uniformity, or inability to adjust electromagnetic field uniformity existing in the original equipment. At the same time, through the design of this device, the equipment can become more diversified in production applications (i.e., one device with multiple functions), thereby reducing production costs and improving product quality and production efficiency.

[0011] In order to solve the above problems, the technical solution adopted by the present invention is as follows: a new type of annular adjustable RF coil device, including a plasma etcher, a chamber is provided inside the plasma etcher, a coil adjustment mechanism is provided inside the chamber, an RF power supply is installed on one side of the plasma etcher, the coil adjustment mechanism includes a coil body, and the coil body can be provided in multiple groups. The present invention shows four groups, and multiple coil bodies are combined into an annular structure. A protrusion is fixedly installed on the outer periphery of one side of the coil body, and a first conductive connecting spring is fixedly installed on one end of the protrusion. An RF coil fixing point is also fixedly installed on the outer periphery of the coil body, and a first adjustment handle is installed on one side of the RF coil fixing point. A support fixing plate is also installed on the first adjustment handle, and an installation mechanism is commonly connected between the RF power supply and the coil adjustment mechanism.

[0012] Preferably, a pipeline is installed in the middle of the plasma etcher, an electrode is provided at the lower end of the plasma etcher, and a vacuum pipeline is installed on one side of the electrode.

[0013] Preferably, a protective cover is provided on the outer periphery of the lower end of the supporting fixing plate, and a second adjustment handle is mounted on the protective cover.

[0014] Preferably, the mounting mechanism includes a first conductive copper sheet connected to the radio frequency power supply, and one end of the first conductive copper sheet is connected to a second conductive copper sheet via a second conductive connecting spring.

[0015] Preferably, the second conductive copper sheet is connected to the bump via a connector, and a capacitor is provided on one side of the coil body.

[0016] Preferably, a clamping groove is fixedly mounted on one end of the coil body, and a clamping block is fixedly mounted on one end of the coil body away from the clamping groove, and the clamping block is adapted to the clamping groove.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] (1) The coil bodies can be arranged in multiple groups. The present invention shows four groups. The multiple coil bodies are combined into a ring structure. There are gaps between adjacent coil bodies. Coil compensation areas are added outside the incompletely closed areas to compensate for the phenomenon that the electromagnetic field cannot be formed or is formed weakly at the gaps.

[0019] (2) Through the cooperation between the capacitor, the first conductive copper sheet, the second conductive connection spring and the second conductive copper sheet, the current is continuously conducted. At the same time, when the RF coil needs to be adjusted, a certain degree of ductility can be provided to facilitate the adjustment of the RF coil. The material thereof is consistent with that of the first conductive connection spring, both of which are conductive materials with extremely low resistivity. This solves the problem in the prior art that the coil body is fixed and cannot be adjusted and is changed to a segmented spring connection, thereby realizing an adjustable function.

[0020] (3) The second conductive copper sheet is connected to the bump through a connector. A capacitor is provided on one side of the coil body, which has the functions of frequency stabilization, DC isolation, and filtering. The capacitor is moved from the middle of the RF coil to a parallel position on its outside to minimize the gap. The gap is then insulated to ensure that there is no short circuit or arcing.

[0021] (4) A snap-in slot is fixedly installed at one end of the coil body, and a snap-in block is fixedly installed at the end of the coil body away from the snap-in slot. The snap-in block and the snap-in slot are matched. The interface is designed in a handshake style to ensure that the division does not affect the electric field. The new design divides the entire RF coil and uses springs to connect different modules so that their conductive performance is not affected. At the same time, it is changed from the original non-adjustable to adjustable up and down, front and back, thereby realizing the adjustable plasma density in the chamber. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic structural diagram of the plasma etcher of the present invention;

[0023] Figure 2 This is a schematic diagram of the internal structure of the plasma etcher of the present invention;

[0024] Figure 3This is a schematic structural diagram of the coil adjustment mechanism of the present invention;

[0025] Figure 4 A top view of the coil adjustment mechanism of the present invention;

[0026] Figure 5 This is a structural diagram of a coil body embodiment 1 of the present invention;

[0027] Figure 6 This is a structural diagram of the second embodiment of the coil body of the present invention.

[0028] In the figure: 1. Plasma etcher; 11. Chamber; 2. RF power supply; 3. Pipeline; 4. Electrode; 6. Vacuum pipeline; 7. Coil adjustment mechanism; 71. Coil body; 711. Snap-in groove; 712. Snap-in block; 72. Bump; 73. First conductive connection spring; 74. RF coil fixing point; 75. First adjustment handle; 76. Support fixing plate; 77. Protective cover; 78. Second adjustment handle; 8. Mounting mechanism; 81. First conductive copper sheet; 82. Second conductive connection spring; 83. Second conductive copper sheet; 84. Connector; 85. Capacitor. DETAILED DESCRIPTION

[0029] The present invention will be further described below with reference to specific embodiments. Example

[0030] like Figure 1-Figure 5 As shown, a novel annular adjustable RF coil device includes a plasma etcher 1, an RF power supply 2 is installed on one side of the plasma etcher 1, a chamber 11 is provided inside the plasma etcher 1, and a coil adjustment mechanism 7 is provided inside the chamber 11, which is a fixed regulator for fixing and adjusting the RF coil. The coil adjustment mechanism 7 includes a coil body 71, which is used to generate an electromagnetic field. The coil body 71 can be set in multiple groups. The present invention shows a four-group setting. The multiple coil bodies 71 are combined into an annular structure. Gaps are opened between adjacent coil bodies 71, and insulation is performed at the gaps. A coil compensation area is added outside the incompletely closed area to compensate for the phenomenon that no electromagnetic field can be formed or a weak electromagnetic field is formed at the gap.

[0031] A bump 72 is fixedly mounted on the outer periphery of one side of the coil body 71. To compensate for the defect of the gap in generating an electromagnetic field when the RF coil is segmented, thereby ensuring the uniformity and integrity of the overall magnetic field, a first conductive connection spring 73 is fixedly mounted on one end of the bump 72. Its main function is to conduct the circuit, connect the segmented RF coils together, and provide the RF coil with ductility, thereby achieving position adjustment. The outer periphery of the coil body 71 is also fixedly mounted with an RF coil fixing point 74, which is used to connect the RF coil to the adjustment fixture. A first adjustment handle 75 is mounted on one side of the RF coil fixing point 74. Its main function is to drive the forward and backward braking of the RF coil and also record the value of each adjustment. A supporting fixing plate 76 is also mounted on the first adjustment handle 75. Its main function is to fix the first adjustment handle 75 and also to drive the upper and lower adjustment points of the RF coil. A mounting mechanism 8 is connected between the RF power supply 2 and the coil adjustment mechanism 7. The mounting mechanism 8 is placed outside the frequency band coil to reduce the distance at its interface, thereby achieving the closed integrity of the entire frequency band coil.

[0032] The new design also changes the fixed base of the frequency coil so that it no longer serves as a fixed base alone, but also serves as the braking center point for adjusting the frequency coil up and down and forward and backward.

[0033] A pipeline 3 is installed in the middle of the plasma etcher 1 , and a silent chuck is provided at the lower end of the plasma etcher 1 . The silent chuck is an electrode 4 , and a vacuum pipeline 6 is installed on one side of the electrode 4 .

[0034] A protective cover 77 is provided on the outer periphery of the lower end of the supporting fixing plate 76, which is used to protect the internal structure of the RF regulator and support the entire RF regulator. The material of the protective cover 77 is an insulating ceramic part, which also ensures the relative insulation between the RF coil and the equipment chamber. A second adjustment handle 78 is installed on the protective cover 77, which is used to drive the supporting fixing plate 76 to realize the up and down braking of the RF coil, and can also record the value of each adjustment.

[0035] The mounting mechanism 8 includes a first conductive copper sheet 81 connected to the RF power supply 2. One end of the first conductive copper sheet 81 is connected to a second conductive copper sheet 83 via a second conductive connection spring 82, so that the current is not interrupted and can provide a certain degree of ductility when the RF coil needs to be adjusted. The material of the first conductive copper sheet 81 is consistent with that of the first conductive connection spring 73, both of which are conductive materials with extremely low resistivity. This solves the problem of the coil body 71 being fixed and non-adjustable in the prior art and changes it to a segmented spring connection, thereby realizing the adjustable function.

[0036] The second conductive copper sheet 83 is connected to the bump 72 through a connector 84. A capacitor 85 is provided on one side of the coil body 71, which has the functions of frequency stabilization, DC isolation, and filtering. The capacitor 85 is changed from the sandwiched position in the middle of the frequency line coil to the parallel position on its outside, so that the gap is minimized, and insulation treatment is performed at the gap to ensure that there will be no short circuit or arc. Example

[0037] like Figure 1-Figure 4 , Figure 6 As shown, a novel annular adjustable RF coil device includes a plasma etcher 1, an RF power supply 2 is installed on one side of the plasma etcher 1, a chamber 11 is provided inside the plasma etcher 1, and a coil adjustment mechanism 7 is provided inside the chamber 11, which is a fixed regulator for fixing and adjusting the RF coil. The coil adjustment mechanism 7 includes a coil body 71, which is used to generate an electromagnetic field. The coil body 71 can be provided in multiple groups. The present invention shows four groups. The multiple coil bodies 71 are combined into an annular structure. Gaps are opened between adjacent coil bodies 71. Coil compensation areas are added outside the incompletely closed areas to compensate for the phenomenon that no electromagnetic field can be formed or a weak electromagnetic field is formed at the gaps.

[0038] A bump 72 is fixedly mounted on the outer periphery of one side of the coil body 71. To compensate for the defect of the gap in generating an electromagnetic field when the RF coil is segmented, thereby ensuring the uniformity and integrity of the overall magnetic field, a first conductive connection spring 73 is fixedly mounted on one end of the bump 72. Its main function is to conduct the circuit, connect the segmented RF coils together, and provide the RF coil with ductility, thereby achieving position adjustment. The outer periphery of the coil body 71 is also fixedly mounted with an RF coil fixing point 74, which is used to connect the RF coil to the adjustment fixture. A first adjustment handle 75 is mounted on one side of the RF coil fixing point 74. Its main function is to drive the forward and backward braking of the RF coil and also record the value of each adjustment. A supporting fixing plate 76 is also mounted on the first adjustment handle 75. Its main function is to fix the first adjustment handle 75 and also to drive the upper and lower adjustment points of the RF coil. A mounting mechanism 8 is connected between the RF power supply 2 and the coil adjustment mechanism 7. The mounting mechanism 8 is placed outside the frequency band coil to reduce the distance at its interface, thereby achieving the closed integrity of the entire frequency band coil.

[0039] The new design also changes the fixed base of the frequency coil so that it no longer serves as a fixed base alone, but also serves as the braking center point for adjusting the frequency coil up and down and forward and backward.

[0040] A pipeline 3 is installed in the middle of the plasma etcher 1 , and a silent chuck is provided at the lower end of the plasma etcher 1 . The silent chuck is an electrode 4 , and a vacuum pipeline 6 is installed on one side of the electrode 4 .

[0041] A protective cover 77 is provided on the outer periphery of the lower end of the supporting fixing plate 76, which is used to protect the internal structure of the RF regulator and support the entire RF regulator. The material of the protective cover 77 is an insulating ceramic part, which also ensures the relative insulation between the RF coil and the equipment chamber. A second adjustment handle 78 is installed on the protective cover 77, which is used to drive the supporting fixing plate 76 to realize the up and down braking of the RF coil, and can also record the value of each adjustment.

[0042] The mounting mechanism 8 includes a first conductive copper sheet 81 connected to the RF power supply 2. One end of the first conductive copper sheet 81 is connected to a second conductive copper sheet 83 via a second conductive connection spring 82, so that the current is not interrupted and can provide a certain degree of ductility when the RF coil needs to be adjusted. The material of the first conductive copper sheet 81 is consistent with that of the first conductive connection spring 73, both of which are conductive materials with extremely low resistivity. This solves the problem of the coil body 71 being fixed and non-adjustable in the prior art and changes it to a segmented spring connection, thereby realizing the adjustable function.

[0043] The second conductive copper sheet 83 is connected to the bump 72 through a connector 84. A capacitor 85 is provided on one side of the coil body 71, which has the functions of frequency stabilization, DC isolation, and filtering. The capacitor 85 is changed from the sandwiched position in the middle of the frequency line coil to the parallel position on its outside, so that the gap is minimized, and insulation treatment is performed at the gap to ensure that there will be no short circuit or arc.

[0044] A snap-in slot 711 is fixedly installed at one end of the coil body 71, and a snap-in block 712 is fixedly installed at the end of the coil body 71 away from the snap-in slot 711. The snap-in block 712 is adapted to the snap-in slot 711, and the interface is designed in a handshake type to ensure that the division does not affect the electric field. The new design divides the entire RF coil and insulates the division to prevent problems such as arcing. Springs are used to connect different modules so that their conductive performance is not affected. At the same time, the original non-adjustable state is changed to adjustable up and down, front and back, thereby achieving adjustable plasma density in the chamber.

[0045] The contents not described in detail in this specification belong to the prior art known to those skilled in the art.

[0046] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A novel ring-shaped adjustable radio frequency coil device, comprising a plasma etcher (1), wherein a chamber (11) is provided inside the plasma etcher (1), a coil adjustment mechanism (7) is provided outside the chamber (11), and a radio frequency power supply (2) is installed on one side of the plasma etcher (1), characterized in that: The coil adjustment mechanism (7) includes a coil body (71), wherein the coil body (71) is provided in a plurality of groups, and the plurality of coil bodies (71) are combined into a ring structure. A protrusion (72) is fixedly mounted on the periphery of one side of the coil body (71), and a first conductive connection spring (73) is fixedly mounted on one end of the protrusion (72). A radio frequency coil fixing point (74) is also fixedly mounted on the periphery of the coil body (71), and a first adjustment handle (75) is mounted on one side of the radio frequency coil fixing point (74). A supporting fixing plate (76) is also mounted on the first adjustment handle (75). A mounting mechanism (8) is commonly connected between the radio frequency power supply (2) and the coil adjustment mechanism (7); One end of the coil body (71) is also fixedly mounted with a clamping groove (711), and one end of the coil body (71) away from the clamping groove (711) is fixedly mounted with a clamping block (712), the clamping block (712) being adapted to the clamping groove (711).

2. The novel annular adjustable radio frequency coil device according to claim 1, characterized in that: A pipeline (3) is installed in the middle of the plasma etcher (1), an electrode (4) is provided at the lower end of the plasma etcher (1), and a vacuum pipeline (6) is installed in communication with one side of the electrode (4).

3. The novel annular adjustable radio frequency coil device according to claim 2, characterized in that: A protective cover (77) is provided on the outer periphery of the lower end of the supporting fixing plate (76), and a second adjustment handle (78) is mounted on the protective cover (77).

4. The novel annular adjustable radio frequency coil device according to claim 3, characterized in that: The mounting mechanism (8) comprises a first conductive copper sheet (81) connected to the radio frequency power supply (2), and one end of the first conductive copper sheet (81) is connected to a second conductive copper sheet (83) via a second conductive connection spring (82).

5. The novel annular adjustable radio frequency coil device according to claim 4, characterized in that: The second conductive copper sheet (83) is connected to the bump (72) via a connector (84), and a capacitor (85) is provided on one side of the coil body (71).

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