Segmented radio frequency coil

Abstract

The application provides a segmented radio frequency coil, which comprises an inner coil and an outer coil, wherein the cross-sectional area of the inner coil is larger than that of the outer coil, and at least one notch is formed in the inner coil and penetrates the inner coil in the height direction; the outer coil is arranged corresponding to the notch, is wrapped outside the inner coil and is connected to the inner coil at the notch, and comprises two free ends. The application has a voltage shielding function and reduces the physical bombardment degree of plasma on a process chamber.

Description

Technical Field

[0001] This invention belongs to the field of plasma technology, and in particular relates to a segmented radio frequency coil. Background Technology

[0002] like Figure 1 As shown, in the prior art, plasma is generated by ionizing the source gas of the target material through a traditional radio frequency coil and relying on radio frequency induction. In essence, it is to continuously accelerate electrons through a high-frequency electromagnetic field, induce collision ionization, and finally form a self-sustaining plasma.

[0003] However, the following drawback exists: traditional RF coil designs have no electric field shielding effect, resulting in a high degree of physical bombardment of the process chamber walls by plasma. Summary of the Invention

[0004] The purpose of this invention is to provide a segmented radio frequency coil with built-in voltage shielding. The technical solution adopted is as follows:

[0005] A segmented radio frequency coil includes: an inner coil and an outer coil;

[0006] The inner coil has a larger cross-sectional area than the outer coil, and has at least one notch that penetrates the inner coil along the height direction.

[0007] The outer coil, corresponding to the notch, wraps around the outside of the inner coil and connects to the inner coil where the notch is located. It includes two free ends, and an radio frequency power supply is applied between all the free ends of the outer coil.

[0008] Preferably, the number of gaps is 2 to divide the inner coil into 2 independent coil segments A5 and B2, with one gap forming between one end of coil A5 and coil B2, and the other gap forming between the other end of coil A5 and coil B2;

[0009] The outer coil includes:

[0010] Segment 6 and segment 3, one end of segment 6 is connected to coil A5 and is located near the notch, the other end of which is a free end, and the other end of which wraps around coil B2 in a circumferential direction and in a counterclockwise direction; one end of segment 3 is connected to coil B2 and is located near the notch, the other end of which is a free end, and the other end of which wraps around coil A5 in a circumferential direction and in a clockwise direction;

[0011] Segment 4 and segment 1, one end of segment 4 is connected to coil A5 and is located near the second notch, the other end of which is a free end and wraps around coil B2 in a circumferential and clockwise direction; one end of segment 1 is connected to coil B2 and is located near the second notch, the other end of which is a free end and wraps around coil A5 in a circumferential and counterclockwise direction.

[0012] Preferably, the number of the gaps is 1 to divide the inner coil 7 into coil A and coil B, with one end of coil A forming the gap between coil A and coil B, and the other end of coil A connected to coil B;

[0013] The outer coil includes: segment 8 (number one) and segment 9 (number two);

[0014] The first segment 8 has one end connected to coil A and set near the gap, and the other end is a free end. The other end wraps around the inner coil 7 in a circumferential direction and in a clockwise direction and extends to the gap.

[0015] The second segment 9 has one end connected to coil B and positioned near the notch, and the other end is a free end. The other end wraps around the inner coil 7 in a circumferential direction and extends to the notch in a counterclockwise direction.

[0016] Preferably, the inner coil is wrapped around the outside of the process chamber.

[0017] Preferably, the inner coil is arc-shaped.

[0018] Preferably, the notch includes: a vertical notch one, a horizontal notch and a vertical notch two connected in sequence.

[0019] Compared with the prior art, the advantages of the present invention are:

[0020] 1. It has built-in voltage shielding function, which reduces capacitive coupling inside the cavity.

[0021] 2. It reduces the physical bombardment of plasma on quartz or ceramic barrels, thereby extending the life of the process chamber (quartz or ceramic barrel), reducing the generation of particulate matter in the chamber, and reducing capacitive coupling. Attached Figure Description

[0022] Figure 1 This diagram shows the positional relationship between the traditional RF coil and the process chamber.

[0023] Figure 2 This is a diagram showing the positional relationship between the RF coil and the process chamber in Example 1;

[0024] Figure 3 for Figure 2 The state diagram formed after rotating 90 degrees clockwise;

[0025] Figure 4 for Figure 3 Top view;

[0026] Figure 5 This is a voltage distribution diagram on the segmented radio frequency coil after applying radio frequency power in Example 1;

[0027] Figure 6 This is a diagram showing the positional relationship between the RF coil and the process chamber in Example 2;

[0028] Figure 7 for Figure 6 Top view;

[0029] Figure 8 for Figure 6 The front view;

[0030] Figure 9 This is a voltage distribution diagram on the segmented radio frequency coil after applying radio frequency power in Example 2.

[0031] Among them, 1-segment one, 2-coil B, 3-segment three, 4-segment four, 5-coil A, 6-segment six, 7-inner coil, 8-segment one, 9-segment two. Detailed Implementation

[0032] The segmented radio frequency coil of the present invention will now be described in more detail with reference to the schematic diagrams, which illustrate preferred embodiments of the invention. It should be understood that those skilled in the art can modify the invention described herein while still achieving its advantageous effects. Therefore, the following description should be understood as being of general knowledge to those skilled in the art and is not intended to limit the invention.

[0033] A segmented radio frequency coil includes: an inner coil and an outer coil;

[0034] The inner coil has a larger cross-sectional area than the outer coil, and has at least one notch that extends through the inner coil along the height direction.

[0035] The outer coil, corresponding to the notch, is wrapped around the outside of the inner coil and connected to the inner coil where the notch is located. It includes two free ends, and an radio frequency power supply is applied between all the free ends of the outer coil.

[0036] The existing technology connects a radio frequency (RF) sensor, an RF power supply, and a matching device capable of performing impedance matching or output frequency matching operations on the high-frequency power supply between all free ends to achieve the application of RF power between all free ends.

[0037] Example 1

[0038] In this embodiment, the number of notches is 2. The notches have the same structure.

[0039] The gaps include: vertical gap one, horizontal gap and vertical gap two connected in sequence.

[0040] like Figures 2-4 The inner coil is divided into two independent coil segments, A5 and B2. A gap one is formed between one end of coil A5 and coil B2, and a gap two is formed between the other end of coil A5 and coil B2.

[0041] The inner coil is arc-shaped.

[0042] The outer coil includes:

[0043] A radio frequency power supply is applied between the free ends of segment 6 and segment 3. One end of segment 6 is connected to coil A5 and is located near the notch, while the other end is a free end. The other end of segment 6 wraps around coil B2 in a circumferential and counterclockwise direction. One end of segment 3 is connected to coil B2 and is located near the notch, while the other end of segment 3 is a free end. The other end of segment 3 wraps around coil A5 in a circumferential and clockwise direction.

[0044] Radio frequency power is applied between the free ends of segment 4 and segment 1. One end of segment 4 is connected to coil A5 (by welding, threading, or rivet) and is located near notch 2. The other end is a free end, which wraps around coil B2 in a circumferential and clockwise direction. One end of segment 1 is connected to coil B2 and is located near notch 2. The other end is a free end, which wraps around coil A5 in a circumferential and counterclockwise direction.

[0045] In use, the inner coil is wrapped around the outside of the process chamber. The inner coil is supported and fixed by an insulating bracket.

[0046] like Figure 5 The figure shows the voltage distribution after applying an RF power supply. The X-axis represents the coil position, and the Y-axis represents the voltage value.

[0047] Regarding voltage distribution: additional instruments will be used to measure it during the design phase, and it will be detected and monitored during subsequent use.

[0048] The distribution is a sine wave, which is divided into 6 segments, as shown in the numbers, corresponding to the 6 segments of the RF coil designed in this embodiment. That is, voltage segments 1, 3, 4, and 6 are the voltages of segment 1, segment 3, segment 4, and segment 6, respectively; voltage segments 2 and 5 are the voltages of coil A5 and coil B2, respectively.

[0049] It can be seen that voltage segments 2 and 5 are the lowest (and the corresponding electric fields are also low), while voltage segments 1, 3, 4, and 6 are higher (and the corresponding electric fields are also higher). However, voltage segments 1, 3, 4, and 6 are shielded by coil A5 and coil B2.

[0050] That is, the voltages corresponding to coils A5 and B2 are too low, while the voltages of segments 1, 3, 4, and 6 of the outer coil are too high. However, the voltages of segments 1, 3, 4, and 6 are shielded by the inner coils A5 and B2.

[0051] "The voltages of segments 1, 3, 4, and 6 are shielded by coils A5 and B2" means that the voltage at the inner coil is lower than the voltage at the outer coil, thus the inner coil shields part of the voltage of the outer coil.

[0052] However, the magnetic fields generated by segments 1, 3, 4, and 6 will not be isolated by the inner coils (coil A5 and coil B2).

[0053] Example 2

[0054] In this embodiment, the number of gaps is 1.

[0055] like Figures 6-8 As shown, the inner coil 7 is divided into coil A and coil B. One end of coil A forms a gap with coil B, and the other end of coil A is connected to coil B.

[0056] The outer coil includes: segment 8 (number 1) and segment 9 (number 2);

[0057] Segment 8 has one end connected to coil A and located near the notch, and the other end is a free end. The other end wraps around the inner coil 7 in a circumferential and clockwise direction and extends to the notch.

[0058] The second segment 9 has one end connected to coil B and positioned near the notch, and the other end is a free end. The other end wraps around the inner coil 7 in a circumferential direction and in a counterclockwise direction and extends to the notch.

[0059] like Figure 9 As shown, the voltage distribution after radio frequency is applied to the coil is a part of a sine wave, which is divided into 3 segments, as shown by the numbers, corresponding to the 3 segments of the coil in this embodiment.

[0060] It can be seen that the voltage of inner coil 7 is the lowest (and the corresponding electric field is also low), while the voltage of segment 8 and segment 9 is higher (and the corresponding electric field is also higher). However, segment 8 and segment 9 are shielded by the inner coil 7 designed in this case.

[0061] However, the magnetic fields generated by segments 8 and 9 will not be isolated by the inner coil 7.

[0062] In summary, this invention reduces the bombardment of the quartz or ceramic barrel by the plasma through the coil itself (the wider portion, with a lower voltage) and the strong electric field generated by the inner coil shielding coil (the narrower portion, with a higher voltage), thereby extending the lifespan of the quartz or ceramic barrel, reducing particulate matter in the cavity, and reducing the capacitive coupling of the plasma.

[0063] Since the radio frequency voltage generated by the radio frequency power supply remains unchanged compared to existing technologies, radio frequency induction can be performed.

[0064] The above are merely preferred embodiments of the present invention and do not constitute any limitation on the present invention. Any equivalent substitutions or modifications made by those skilled in the art to the technical solutions and content disclosed in the present invention without departing from the scope of the present invention shall be deemed to have remained within the protection scope of the present invention.

Claims

1. A segmented radio frequency coil, characterized in that, include: Inner coil and outer coil; The inner coil has a larger cross-sectional area than the outer coil, and has at least one notch that penetrates the inner coil along its height. When there are two notches, the voltage on the different coils of the inner coil is equal. The outer coil, corresponding to the notch, wraps around the outside of the inner coil and connects to the inner coil where the notch is located, and includes two free ends; The number of gaps is 2 to divide the inner coil into 2 independent coils A (5) and B (2), with one gap forming between one end of coil A (5) and coil B (2), and the other end of coil A (5) and coil B (2) forming a gap 2; The outer coil includes: Segment 6 (6) and segment 3 (3), one end of segment 6 (6) is connected to coil A (5) and set near the gap, the other end of which is a free end, and the other end of which wraps around coil B (2) in a circumferential direction and in a counterclockwise direction; one end of segment 3 (3) is connected to coil B (2) and set near the gap, the other end of which is a free end, and the other end of which wraps around coil A (5) in a circumferential direction and in a clockwise direction. Segment 4 (4) and Segment 1 (1), one end of Segment 4 (4) is connected to coil A (5) and set near the second gap, the other end of which is a free end, and the other end of which wraps around the coil B (2) in a circumferential direction and in a clockwise direction; one end of Segment 1 (1) is connected to coil B (2) and set near the second gap, the other end of which is a free end, and the other end of which wraps around the coil A (5) in a circumferential direction and in a counterclockwise direction.

2. The segmented radio frequency coil according to claim 1, characterized in that, The inner coil is wrapped around the outside of the process chamber.

3. The segmented radio frequency coil according to claim 1, characterized in that, The inner coil is arc-shaped.

4. The segmented radio frequency coil according to claim 1, characterized in that, The gaps include: a vertical gap one, a horizontal gap, and a vertical gap two that are connected in sequence.

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