Inductively coupled reactor and method of operation thereof

Abstract

An inductively coupled reactor and a method for operating the same. The inductively coupled reactor comprises a reactor cavity body, an inductively coupled radio frequency unit located above the reactor cavity body, the inductively coupled radio frequency unit comprising a shield, a reactor chamber dielectric tube located inside the shield, a side wall of the reactor chamber dielectric tube being inclined and a top cross section of the reactor chamber dielectric tube being smaller than a bottom cross section, an upper radio frequency antenna and a lower radio frequency antenna located inside the shield and distributed on the side of the reactor chamber dielectric tube, the upper radio frequency antenna and the lower radio frequency antenna being separate from each other, and a radio frequency power fed into the upper radio frequency antenna and a radio frequency power fed into the lower radio frequency antenna being adjustable respectively. The inductively coupled reactor can enhance the control ability of plasma distribution.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of semiconductor manufacturing, and in particular to an inductive coupling reactor and a working method thereof. BACKGROUND

[0002] In semiconductor manufacturing, a plurality of processes are involved, each of which is completed by certain equipment and process. Among them, etching process is an important process in semiconductor manufacturing, such as plasma etching process. Plasma etching process is to generate plasma by using reactive gas after obtaining energy, including charged particles such as ions, electrons, and highly chemically active neutral atoms, molecules and free radicals, and to etch the etching object through physical and chemical reactions.

[0003] However, in the plasma etching process, the etching conditions of the wafer edge and the wafer center are quite different, including plasma density distribution, radio frequency electric field, temperature distribution, etc. Among them, the plasma density distribution is a very important etching condition. For example, generally, the plasma density distributed above the wafer center region is greater than that distributed above the wafer edge region, and this distribution is difficult to adjust.

[0004] Therefore, it is necessary to propose an inductive coupling reactor capable of controllably adjusting the plasma distribution to meet the needs. SUMMARY

[0005] The problem solved by the present application is to provide an inductive coupling reactor and a working method thereof, which can enhance the control ability of the plasma distribution.

[0006] In order to solve the above technical problems, the present application provides an inductive coupling reactor, comprising: a reaction chamber main body; an inductive coupling radio frequency unit located above the reaction chamber main body; the inductive coupling radio frequency unit comprises: a shielding cover; a reaction chamber dielectric tube located inside the shielding cover, the side wall of the reaction chamber dielectric tube is inclined and the top cross section of the reaction chamber dielectric tube is smaller than the bottom cross section; an upper radio frequency antenna and a lower radio frequency antenna located inside the shielding cover and distributed on the side of the reaction chamber dielectric tube, the upper radio frequency antenna and the lower radio frequency antenna are separate from each other, and the radio frequency power fed into the upper radio frequency antenna and the radio frequency power fed into the lower radio frequency antenna are adjustable respectively.

[0007] Optionally, the longitudinal section shape of the reaction chamber dielectric tube is trapezoidal.

[0008] Optionally, the lower radio frequency antenna has a first antenna terminal and a second antenna terminal, the upper radio frequency antenna has a third antenna terminal and a fourth antenna terminal; the first antenna terminal is adapted to feed a first radio frequency, the third antenna terminal is adapted to feed a second radio frequency, and the sizes of the first radio frequency and the second radio frequency are adjustable.

[0009] Optionally, the inductive coupling radio frequency unit further comprises: a radio frequency source; a radio frequency matcher, one end of the radio frequency matcher being connected with the radio frequency source; a first power divider, one end of the first power divider being connected with the other end of the radio frequency matcher, and the other end of the first power divider being connected with the first antenna terminal; a second power divider, one end of the second power divider being connected with the other end of the radio frequency matcher, and the other end of the second power divider being connected with the third antenna terminal; a first voltage balance capacitor, one end of the first voltage balance capacitor being connected with the second antenna terminal, and the other end of the first voltage balance capacitor being grounded; and a second voltage balance capacitor, one end of the second voltage balance capacitor being connected with the fourth antenna terminal, and the other end of the second voltage balance capacitor being grounded.

[0010] Optionally, the inductive coupling radio frequency unit further comprises: a radio frequency source; a radio frequency matcher, one end of the radio frequency matcher being connected with the radio frequency source, and the other end of the radio frequency matcher being connected with the first antenna terminal; a voltage balance capacitor, one end of the voltage balance capacitor being connected with the second antenna terminal; a switch, the switch being connected with the other end of the voltage balance capacitor, and the switch being selectable to be connected with the third antenna terminal or grounded; and an impedance matching capacitor, one end of the impedance matching capacitor being connected with the fourth antenna terminal, and the other end of the impedance matching capacitor being grounded. Optionally, the inductive coupling radio frequency unit further comprises: a radio frequency source; a radio frequency matcher, one end of the radio frequency matcher being connected with the radio frequency source, and the other end of the radio frequency matcher being connected with the third antenna terminal; a voltage balance capacitor, one end of the voltage balance capacitor being connected with the fourth antenna terminal; a switch, the switch being connected with the other end of the voltage balance capacitor, and the switch being selectable to be connected with the first antenna terminal or grounded; and an impedance matching capacitor, one end of the impedance matching capacitor being connected with the second antenna terminal, and the other end of the impedance matching capacitor being grounded.

[0011] Optionally, the switch comprises a relay.

[0012] Optionally, the inductance L1 of the upper radio frequency antenna, the impedance matching capacitor C1, and the radio frequency ω of the radio frequency source satisfy: ω = (L1*C1) 1 / 2 .

[0013] Optionally, the inductance L2 of the lower radio frequency antenna, the impedance matching capacitor C1, and the radio frequency ω of the radio frequency source satisfy: ω = (L2*C1) 1 / 2 .

[0014] Optionally, the inductive coupling reactor further comprises a wafer clamping platform located at the bottom of the reaction chamber body; the upper radio frequency antenna and the lower radio frequency antenna are used to generate plasma inside the reaction chamber medium tube, and the plasma is adapted to enter between the wafer clamping platform and the reaction chamber medium tube through the reaction chamber medium tube.

[0015] Optionally, the inductive coupling radio frequency unit further comprises an air inlet channel located at the top of the reaction chamber medium tube, and the air inlet channel is adapted to introduce etching gas for etching a wafer into the reaction chamber medium tube.

[0016] Optionally, the inductive coupling reactor further comprises a cooling device located at the top of the shielding cover, and the cooling device is used to cool the radio frequency antenna and the reaction chamber medium tube.

[0017] The application further provides a working method of an inductive coupling reactor, which adopts any one of the inductive coupling reactors described above, and comprises the following steps: placing a wafer in the reaction chamber body; adjusting the radio frequency power fed into the upper radio frequency antenna and the radio frequency power fed into the lower radio frequency antenna; after adjusting the radio frequency power fed into the upper radio frequency antenna and the radio frequency power fed into the lower radio frequency antenna, the upper radio frequency antenna and the lower radio frequency antenna generate plasma inside the reaction chamber medium tube, and the plasma enters the reaction chamber body to etch the wafer.

[0018] Optionally, the inductive coupling radio frequency unit further comprises a radio frequency source, a radio frequency matcher connected with one end of the radio frequency source, a first power distributor connected with the other end of the radio frequency matcher, a second power distributor connected with the other end of the radio frequency matcher, a first voltage balance capacitor connected with the second antenna terminal and grounded at the other end, and a second voltage balance capacitor connected with the fourth antenna terminal and grounded at the other end; and the adjusting of the radio frequency power fed into the upper radio frequency antenna and the radio frequency power fed into the lower radio frequency antenna comprises the following steps: adjusting the radio frequency power fed into the lower radio frequency antenna by using the first power distributor, and adjusting the radio frequency power fed into the upper radio frequency antenna by using the second power distributor.

[0019] Optionally, the inductive coupling radio frequency unit further comprises: a radio frequency source; a radio frequency matcher; a voltage balance capacitor; a switch; an impedance matching capacitor; one end of the radio frequency matcher is connected with the radio frequency source, and the other end of the radio frequency matcher is connected with the first antenna terminal; one end of the voltage balance capacitor is connected with the second antenna terminal; the switch is connected with the other end of the voltage balance capacitor, and the switch is selectively connected with the third antenna terminal or grounded; one end of the impedance matching capacitor is connected with the fourth antenna terminal, and the other end of the impedance matching capacitor is grounded; and adjusting the radio frequency power fed by the upper radio frequency antenna and the radio frequency power fed by the lower radio frequency antenna comprises: switching the switch between the third antenna terminal and the ground.

[0020] Optionally, the inductive coupling radio frequency unit further comprises: a radio frequency source; a radio frequency matcher; a voltage balance capacitor; a switch; an impedance matching capacitor; one end of the radio frequency matcher is connected with the radio frequency source, and the other end of the radio frequency matcher is connected with the third antenna terminal; one end of the voltage balance capacitor is connected with the fourth antenna terminal; the switch is connected with the other end of the voltage balance capacitor, and the switch is selectively connected with the first antenna terminal or grounded; one end of the impedance matching capacitor is connected with the second antenna terminal, and the other end of the impedance matching capacitor is grounded; and adjusting the radio frequency power fed by the upper radio frequency antenna and the radio frequency power fed by the lower radio frequency antenna comprises: switching the switch between the first antenna terminal and the ground.

[0021] Compared with the prior art, the technical scheme of the present application has the following beneficial effects:

[0022] The inductive coupling reactor provided by the technical scheme of the present application, the effective radio frequency antenna is used to generate plasma in the reaction chamber medium tube. Since the side wall of the reaction chamber medium tube is inclined and the top cross section of the reaction chamber medium tube is smaller than the bottom cross section, the gas diffuses more uniformly in the reaction chamber medium tube. Further, the upper radio frequency antenna and the lower radio frequency antenna are arranged inside the shielding cover and distributed on the side of the reaction chamber medium tube, and the radio frequency power fed by the upper radio frequency antenna and the radio frequency power fed by the lower radio frequency antenna are adjustable respectively, so that the plasma density distribution inside the reaction chamber medium tube can be adjusted by adjusting the radio frequency power fed by the upper radio frequency antenna and the radio frequency power fed by the lower radio frequency antenna respectively, and the distribution of the plasma after entering the reaction cavity body is better controlled, and the wafer in the reaction cavity body is subjected to corresponding controllable etching. In summary, the inductive coupling reactor can strengthen the control ability of the plasma distribution. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 It is a sectional structure schematic diagram of an inductive coupling reactor;

[0024] Figure 2 is a cross-sectional structure diagram of an inductive coupling reactor in an embodiment of the present application;

[0025] Figure 3 is a working method of an inductive coupling reactor in another embodiment of the present application;

[0026] Figure 4 is a cross-sectional structure diagram of an inductive coupling reactor in another embodiment of the present application;

[0027] Figure 5 is a cross-sectional structure diagram of an inductive coupling reactor in another embodiment of the present application. DETAILED DESCRIPTION

[0028] As described in the background, in the existing inductive coupling reactor, it is difficult to control the distribution of the generated plasma.

[0029] An inductive coupling reactor, referring to Figure 1 , comprises an inductive coupling radio frequency unit, the inductive coupling radio frequency unit comprises a shielding cover 1000, a reaction chamber medium tube 1001 inside the shielding cover 1000, a disc incense-shaped radio frequency antenna 1002 on the side wall of the reaction chamber medium tube 1001, the shape of the reaction chamber medium tube 1001 is columnar, and the disc incense-shaped radio frequency antenna 1002 surrounds the reaction chamber medium tube 1001, and the position of the disc incense-shaped radio frequency antenna 1002 is fixed.

[0030] The above-mentioned inductive coupling reactor, gas is introduced into the reaction chamber medium tube 1001 from the gas inlet pipe 1003 at the top of the reaction chamber medium tube 1001, mixed in the columnar reaction chamber medium tube 1001, the radio frequency antenna 1002 generates plasma in the reaction chamber medium tube 1001, and the plasma is diffused into the reaction cavity body, the wafer is located in the reaction cavity body and opposite to the inductive coupling radio frequency unit, the plasma density distribution above the wafer has the characteristics of high in the middle and low at the edge, and cannot be controlled, causing uneven etching.

[0031] Secondly, the top of the shielding cover 1000 is provided with a cooling fan 1004, but since the shape of the reaction chamber medium tube 1001 is columnar, the cooling of the top and the side wall of the reaction chamber medium tube 1001 by the cooling fan 1004 is not too uniform, causing the plasma density distribution in the reaction chamber medium tube 1001 to be uneven, and further causing the plasma density distribution above the wafer to be uneven.

[0032] In order to solve the above technical problems, an embodiment of the present application provides an inductive coupling reactor, referring to Figure 2 , comprising:

[0033] a reaction cavity body 10;

[0034] An inductive coupled radio frequency unit 20 located above the reaction cavity body 10;

[0035] The inductive coupled radio frequency unit 20 comprises: a shield 201; a reaction chamber dielectric tube 202 located inside the shield 201, the side wall of the reaction chamber dielectric tube 202 is inclined and the top cross section of the reaction chamber dielectric tube 202 is smaller than the bottom cross section; an upper radio frequency antenna 203b and a lower radio frequency antenna 203a located inside the shield 201 and distributed on the side of the reaction chamber dielectric tube 202, the upper radio frequency antenna 203b and the lower radio frequency antenna 203a are separate from each other, and the radio frequency power fed into the upper radio frequency antenna 203b and the radio frequency power fed into the lower radio frequency antenna 203a are adjustable respectively.

[0036] In this embodiment, the longitudinal section shape of the reaction chamber dielectric tube 202 is trapezoidal.

[0037] In other embodiments, the reaction chamber dielectric tube 202 can also be conical.

[0038] In this embodiment, the shape of the upper radio frequency antenna 203b is incense-shaped, and the shape of the lower radio frequency antenna 203a is incense-shaped.

[0039] In this embodiment, the upper radio frequency antenna 203b surrounds the upper part of the reaction chamber dielectric tube 202 and has multiple turns of continuous coils, and the distance from each turn of coil to the reaction chamber dielectric tube 202 is equal.

[0040] In this embodiment, the lower radio frequency antenna 203a surrounds the lower part of the reaction chamber dielectric tube 202 and has multiple turns of continuous coils, and the distance from each turn of coil to the reaction chamber dielectric tube 202 is equal.

[0041] In this embodiment, the lower radio frequency antenna 203a has a first antenna terminal 2031 and a second antenna terminal 2032, and the upper radio frequency antenna 203b has a third antenna terminal 2033 and a fourth antenna terminal 2034; the first antenna terminal 2031 is adapted to feed a first radio frequency, the third antenna terminal 2033 is adapted to feed a second radio frequency, and the size of the first radio frequency and the second radio frequency is adjustable.

[0042] In the embodiment, the inductive coupling radio frequency unit 20 further comprises: a radio frequency source 205; a radio frequency matcher 206, one end of the radio frequency matcher 206 being connected with the radio frequency source 205; a first power divider 206a, one end of the first power divider 206a being connected with the other end of the radio frequency matcher 206, and the other end of the first power divider 206a being connected with the first antenna terminal 2031; a second power divider 206b, one end of the second power divider 206b being connected with the other end of the radio frequency matcher 206, and the other end of the second power divider 206b being connected with the third antenna terminal 2033; a first voltage balance capacitor 207a, one end of the first voltage balance capacitor 207a being connected with the second antenna terminal 2032, and the other end of the first voltage balance capacitor 207a being grounded; and a second voltage balance capacitor 207b, one end of the second voltage balance capacitor 207b being connected with the fourth antenna terminal 2034, and the other end of the second voltage balance capacitor 207b being grounded.

[0043] The first voltage balance capacitor 207a functions to keep the second antenna terminal 2032 at a certain voltage, and reduce the voltage difference between the first antenna terminal 2031 and the second antenna terminal 2032, so as to reduce the collision of the plasma with the sidewall of the reaction chamber medium tube 202.

[0044] The second voltage balance capacitor 207b functions to keep the fourth antenna terminal 2034 at a certain voltage, and reduce the voltage difference between the fourth antenna terminal 2034 and the third antenna terminal 2033, so as to reduce the collision of the plasma with the sidewall of the reaction chamber medium tube 202.

[0045] In the embodiment, the wafer clamping platform 103 is arranged at the bottom of the reaction cavity body 10.

[0046] In the embodiment, the lower radio frequency antenna 203a and the upper radio frequency antenna 203b are used to generate plasma inside the reaction chamber medium tube 202, and the plasma is suitable to enter between the wafer clamping platform 103 and the reaction chamber medium tube 202 through the reaction chamber medium tube 202.

[0047] In the embodiment, the inductive coupling radio frequency unit 20 further comprises: a gas inlet channel 208 arranged at the top of the reaction chamber medium tube 202, and suitable to introduce etching gas for etching a wafer into the reaction chamber medium tube 202.

[0048] In the embodiment, the cooling device 209 is arranged at the top of the shielding cover 201, and is used to cool the radio frequency antenna 203 and the reaction chamber medium tube 202.

[0049] Figure 2 The working principle of the inductive coupled reactor is that: the RF power provided by the RF source 205 is fed into the upper RF antenna and the lower RF antenna through the RF matcher 206, the RF power fed into the lower RF antenna 203a is controlled and adjusted by the first power distributor 206a, the RF power fed into the upper RF antenna 203b is controlled and adjusted by the second power distributor 206b, the control of the first power distributor 206a on the RF power fed into the lower RF antenna 203a is independent of the control of the second power distributor 206b on the RF power fed into the upper RF antenna 203b, the voltage of the second antenna terminal of the lower RF antenna is distributed and controlled by the first voltage balance capacitor, the voltage of the fourth antenna terminal of the upper RF antenna is distributed and controlled by the second voltage balance capacitor, the RF current in the coil of the upper RF antenna generates an alternating magnetic field H1 perpendicular to the current plane in the upper part of the trapezoidal reaction chamber medium tube 202, the RF current in the coil of the lower RF antenna generates an alternating magnetic field H2 perpendicular to the current plane in the lower part of the trapezoidal reaction chamber medium tube 202, the alternating magnetic field H1 induces an angular electric field E1 parallel to the direction of the coil current in the upper part of the reaction chamber medium tube 202, the alternating magnetic field H2 induces an angular electric field E2 parallel to the direction of the coil current in the lower part of the reaction chamber medium tube 202, the reaction gas generates high-density plasma under the action of the angular electric fields E1 and E2, the radial density distribution of the plasma can be controlled by the size of the RF power of the upper RF antenna and the RF power of the lower RF antenna, and the regulated plasma is gradually accelerated to the wafer surface by the bias voltage applied on the wafer clamping platform 103, so that the etching process of the wafer is completed.

[0050] The application further provides a working method of the inductive coupled reactor, and the inductive coupled reactor is used, please refer to Figure 3 , and the method comprises the following steps:

[0051] S01: placing a wafer in the reaction cavity body 10;

[0052] S02: adjusting the RF power fed into the upper RF antenna and the RF power fed into the lower RF antenna;

[0053] S03: after the RF power fed into the upper RF antenna and the RF power fed into the lower RF antenna are adjusted, the upper RF antenna and the lower RF antenna generate plasma in the reaction chamber medium tube 202, and the plasma enters the reaction cavity body 10 to etch the wafer.

[0054] Specifically, the wafer is placed on the wafer clamping plate 103, the first power distributor is used to adjust the RF power fed into the lower RF antenna, and the second power distributor is used to adjust the RF power fed into the upper RF antenna.

[0055] Another embodiment of the present application provides an inductive coupling reactor, referring to Figure 4 The inductive coupling reactor in the embodiment is different from the inductive coupling reactor in the previous embodiment in that the inductive coupling radio frequency unit comprises: a radio frequency source 205; a radio frequency matcher 206, one end of the radio frequency matcher 206 being connected with the radio frequency source 205, and the other end of the radio frequency matcher 206 being connected with the first antenna terminal 2031; a voltage balance capacitor 207, one end of the voltage balance capacitor 207 being connected with the second antenna terminal 2032; a switcher 210, the switcher 210 being connected with the other end of the voltage balance capacitor 207, and the switcher 210 being capable of being connected with the third antenna terminal 2033 or being grounded; and an impedance matching capacitor 211, one end of the impedance matching capacitor 211 being connected with the fourth antenna terminal 2034, and the other end of the impedance matching capacitor 211 being grounded.

[0056] The switcher 210 comprises a relay.

[0057] In the embodiment, the inductance L1 of the upper radio frequency antenna, the impedance matching capacitor C1 and the radio frequency frequency ω of the radio frequency source satisfy: ω=(L1*C1) 1 / 2 .

[0058] The same content in the embodiment as in the previous embodiment will not be described in detail.

[0059] The working method of the inductive coupling reactor in the embodiment is different from the working method in the previous embodiment in that the adjustment of the radio frequency power fed by the upper radio frequency antenna and the radio frequency power fed by the lower radio frequency antenna comprises: the switcher 210 switches between the third antenna terminal 2033 and the ground wire.

[0060] In the working method of the inductive coupling reactor in the embodiment, when the switcher 210 is grounded, the upper radio frequency antenna has no radio frequency power fed, and only the lower radio frequency antenna can excite plasma inside the reaction chamber medium tube 202, at this time, the plasma density of the edge is higher.

[0061] In the working method of the inductive coupling reactor in the embodiment, when the switcher 210 is connected with the third antenna terminal 2033, the radio frequency power is fed into both the lower radio frequency antenna and the upper radio frequency antenna; the inductance L1 of the upper radio frequency antenna and the impedance matching capacitor C1 satisfy the series resonance matching condition, i.e. ω=(L1*C1) 1 / 2 , so as not to affect the impedance matching of the whole antenna system.

[0062] Still another embodiment of the present application provides an inductive coupling reactor, referring to Figure 5The inductive coupling reactor in the embodiment is different from the inductive coupling reactor in the previous embodiment in that the inductive coupling radio frequency unit further comprises: a radio frequency source 205; a radio frequency matcher 206, one end of the radio frequency matcher 206 being connected with the radio frequency source 205, and the other end of the radio frequency matcher 206 being connected with the third antenna terminal 2033; a voltage balance capacitor 207, one end of the voltage balance capacitor 207 being connected with the fourth antenna terminal 2034; a switcher 210, the switcher 210 being connected with the other end of the voltage balance capacitor 207, and the switcher 210 being selectable to be connected with the first antenna terminal 2031 or to be grounded; and an impedance matching capacitor 211, one end of the impedance matching capacitor 211 being connected with the second antenna terminal 2032, and the other end of the impedance matching capacitor 211 being grounded.

[0063] The switcher 210 comprises a relay.

[0064] The inductance L2 of the lower radio frequency antenna, the impedance matching capacitor C1 and the radio frequency frequency ω of the radio frequency source satisfy: ω=(L2*C1) 1 / 2 .

[0065] The same content in the embodiment as in the previous embodiment will not be described in detail.

[0066] The working method of the inductive coupling reactor in the embodiment is different from the working method in the previous embodiment in that adjusting the radio frequency power fed into the upper radio frequency antenna and the radio frequency power fed into the lower radio frequency antenna comprises: the switcher 210 switches between the first antenna terminal 2031 and the ground wire.

[0067] In the working method of the inductive coupling reactor in the embodiment, when the switcher 210 is grounded, the lower radio frequency antenna has no radio frequency power fed into, and only the upper radio frequency antenna can excite plasma inside the reaction chamber medium tube 202, at this time, the central plasma density is higher.

[0068] In the working method of the inductive coupling reactor in the embodiment, when the switcher 210 is connected with the first antenna terminal 2031, the radio frequency power is fed into both the lower radio frequency antenna and the upper radio frequency antenna; the inductance L2 of the lower radio frequency antenna, the impedance matching capacitor C1 and the radio frequency frequency ω of the radio frequency source satisfy: ω=(L2*C1) 1 / 2 , so as not to affect the impedance matching of the whole antenna system.

[0069] Although the present application is disclosed as above, the present application is not limited to this. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present application, and the protection scope of the present application should be defined by the scope defined in the claims.

Claims

1. An inductively coupled reactor characterized by, The application relates to an inductive coupling radio frequency unit, which comprises the following parts: a reaction cavity body; an inductive coupling radio frequency unit located above the reaction cavity body; the inductive coupling radio frequency unit comprises the following parts: a shielding cover; a reaction chamber medium tube located inside the shielding cover, the side wall of the reaction chamber medium tube is inclined, and the top cross section of the reaction chamber medium tube is smaller than the bottom cross section; an upper radio frequency antenna and a lower radio frequency antenna located inside the shielding cover and distributed on the side of the reaction chamber medium tube, the upper radio frequency antenna and the lower radio frequency antenna are separate from each other, the radio frequency power fed into the upper radio frequency antenna and the radio frequency power fed into the lower radio frequency antenna are independently adjustable; the upper radio frequency antenna and the lower radio frequency antenna are both disc-shaped coils with multiple turns, and the distance from each turn of the coil to the reaction chamber medium tube is equal; the lower radio frequency antenna has a first antenna terminal and a second antenna terminal, the upper radio frequency antenna has a third antenna terminal and a fourth antenna terminal; the first antenna terminal is adapted to feed in a first radio frequency, and the third antenna terminal is adapted to feed in a second radio frequency, the size of the first radio frequency and the second radio frequency is independently adjustable; the independently adjustable size of the first radio frequency and the second radio frequency fed into the upper radio frequency antenna and the lower radio frequency antenna can adjust the plasma density distribution inside the reaction chamber medium tube, and then the distribution of the plasma entering the reaction cavity body is adjustable and controllable; the inductive coupling radio frequency unit further comprises a cooling device located at the top of the shielding cover, and the cooling device is used for cooling the radio frequency antenna and the reaction chamber medium tube; the inductive coupling radio frequency unit further comprises a wafer clamping platform located at the bottom of the reaction cavity body; the upper radio frequency antenna and the lower radio frequency antenna are used for generating plasma inside the reaction chamber medium tube, and the plasma is adapted to enter the space between the wafer clamping platform and the reaction chamber medium tube through the reaction chamber medium tube; the inductive coupling radio frequency unit further comprises an air inlet channel located at the top of the reaction chamber medium tube, and the air inlet channel is adapted to introduce etching gas for etching a wafer into the reaction chamber medium tube.

2. The inductively coupled reactor of claim 1, wherein, The longitudinal section of the reaction chamber medium tube is in the shape of a trapezoid.

3. The inductively coupled reactor of claim 1, wherein, The inductive coupling radio frequency unit further comprises the following parts: a radio frequency source; a radio frequency matcher, one end of the radio frequency matcher is connected with the radio frequency source; a first power distributor, one end of the first power distributor is connected with the other end of the radio frequency matcher, and the other end of the first power distributor is connected with the first antenna terminal; a second power distributor, one end of the second power distributor is connected with the other end of the radio frequency matcher, and the other end of the second power distributor is connected with the third antenna terminal; a first voltage balance capacitor, one end of the first voltage balance capacitor is connected with the second antenna terminal, and the other end of the first voltage balance capacitor is grounded; and a second voltage balance capacitor, one end of the second voltage balance capacitor is connected with the fourth antenna terminal, and the other end of the second voltage balance capacitor is grounded.

4. The inductively coupled reactor of claim 1, wherein, The inductive coupling radio frequency unit further comprises: a radio frequency source; a radio frequency matcher, one end of the radio frequency matcher being connected with the radio frequency source, the other end of the radio frequency matcher being connected with the first antenna terminal; a voltage balance capacitor, one end of the voltage balance capacitor being connected with the second antenna terminal; a switch, the other end of the voltage balance capacitor being connected with the switch, the switch being capable of being connected with the third antenna terminal or being grounded; an impedance matching capacitor, one end of the impedance matching capacitor being connected with the fourth antenna terminal, the other end of the impedance matching capacitor being grounded.

5. The inductively coupled reactor of claim 1, wherein, The inductive coupling radio frequency unit further comprises: a radio frequency source; a radio frequency matcher, one end of the radio frequency matcher being connected with the radio frequency source, the other end of the radio frequency matcher being connected with the third antenna terminal; a voltage balance capacitor, one end of the voltage balance capacitor being connected with the fourth antenna terminal; a switch, the other end of the voltage balance capacitor being connected with the switch, the switch being capable of being connected with the first antenna terminal or being grounded; an impedance matching capacitor, one end of the impedance matching capacitor being connected with the second antenna terminal, the other end of the impedance matching capacitor being grounded.

6. The inductively coupled reactor of claim 4 or 5, wherein, The switch comprises a relay.

7. The inductively coupled reactor of claim 4, wherein, The inductance L1 of the upper radio frequency antenna, the impedance matching capacitor C1 and the radio frequency frequency ω of the radio frequency source satisfy: ω = (L1 * C1) 1 / 2 .

8. The inductively coupled reactor of claim 5, wherein, The inductance L2 of the lower radio frequency antenna, the impedance matching capacitor C1 and the radio frequency frequency ω of the radio frequency source satisfy: ω = (L2 * C1) 1 / 2 .

9. A method of operating an inductively coupled reactor according to any one of claims 1 to 8, characterized in that The method comprises the following steps: Placing a wafer in the reaction cavity body; Adjusting the radio frequency power fed by the upper radio frequency antenna and the radio frequency power fed by the lower radio frequency antenna; After adjusting the radio frequency power fed by the upper radio frequency antenna and the radio frequency power fed by the lower radio frequency antenna, the upper radio frequency antenna and the lower radio frequency antenna generate plasma inside the reaction chamber medium tube, and the plasma enters the reaction cavity body to etch the wafer.

10. The method of claim 9, wherein the method further comprises: The inductive coupling radio frequency unit further comprises: a radio frequency source; a radio frequency matcher, one end of the radio frequency matcher being connected with the radio frequency source; a first power divider, one end of the first power divider being connected with the other end of the radio frequency matcher, the other end of the first power divider being connected with the first antenna terminal; a second power divider, one end of the second power divider being connected with the other end of the radio frequency matcher, the other end of the second power divider being connected with the third antenna terminal; a first voltage balance capacitor, one end of the first voltage balance capacitor being connected with the second antenna terminal, the other end of the first voltage balance capacitor being grounded; a second voltage balance capacitor, one end of the second voltage balance capacitor being connected with the fourth antenna terminal, the other end of the second voltage balance capacitor being grounded; adjusting the radio frequency power fed by the upper radio frequency antenna and the radio frequency power fed by the lower radio frequency antenna comprises: adjusting the radio frequency power fed by the lower radio frequency antenna by using the first power divider, and adjusting the radio frequency power fed by the upper radio frequency antenna by using the second power divider.

11. The method of claim 9, wherein the method further comprises: The inductive coupling radio frequency unit further comprises: a radio frequency source; a radio frequency matcher; a voltage balance capacitor; a switch; an impedance matching capacitor; one end of the radio frequency matcher is connected with the radio frequency source, and the other end of the radio frequency matcher is connected with the first antenna terminal; one end of the voltage balance capacitor is connected with the second antenna terminal; the switch is connected with the other end of the voltage balance capacitor, and the switch can be selected to be connected with the third antenna terminal or grounded; one end of the impedance matching capacitor is connected with the fourth antenna terminal, and the other end of the impedance matching capacitor is grounded; and adjusting the radio frequency power fed by the upper radio frequency antenna and the radio frequency power fed by the lower radio frequency antenna comprises: switching the switch between the third antenna terminal and the ground.

12. The method of claim 9, wherein the inductively coupled reactor is operated at a frequency of about 13.56 MHz. The inductive coupling radio frequency unit further comprises: a radio frequency source; a radio frequency matcher; a voltage balance capacitor; a switch; an impedance matching capacitor; one end of the radio frequency matcher is connected with the radio frequency source, and the other end of the radio frequency matcher is connected with the third antenna terminal; one end of the voltage balance capacitor is connected with the fourth antenna terminal; the switch is connected with the other end of the voltage balance capacitor, and the switch can be selected to be connected with the first antenna terminal or grounded; one end of the impedance matching capacitor is connected with the second antenna terminal, and the other end of the impedance matching capacitor is grounded. Adjusting the radio frequency power fed by the upper radio frequency antenna and the radio frequency power fed by the lower radio frequency antenna comprises: switching the switch between the first antenna terminal and the ground.

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