TW202127504A - Plasma inductance coil structure, plasma processing equipment and processing method for solving uneven etching issues occurred at different positions having same distance from center of lining - Google Patents

Abstract

The embodiment of the invention discloses a plasma inductance coil structure, plasma processing equipment and processing method. In the plasma inductance coil structure, the magnetic field strength generated by the first portion of the inductance coil is greater than that generated by the second portion, so that the inductance coil may form an asymmetric magnetic field, and the projection of the first portion of the first inductance coil included by at least two inductance coils in a default plane and the projection of the second portion of the second inductance coil in the default plane are at least partially overlapped in the first direction, so as to compensate the magnetic field strength generated by the second portion of the second inductance coil; at the same time, the projection of the second portion of the first inductance coil in the default plane and the projection of the first portion of the second inductance coil in the default plane are at least partially overlapped in the first direction to compensate the magnetic field strength generated by the second portion of the first inductance coil. Furthermore, because at least one capacitor in the first capacitor electrically connected to the first inductance coil and the second capacitor electrically connected to the second inductance coil is an adjustable capacitor, so as to solve the uneven etaching phenomenon.

Description

Plasma induction coil structure, plasma processing equipment and processing method

The present invention relates to the technical field of plasma processing, in particular to a plasma inductor coil structure, plasma processing equipment and processing method.

As the size of integrated circuit wafers becomes smaller and smaller, the requirements for plasma processing equipment are getting higher and higher, so that plasma processing equipment using this technology is continuously improved. The plasma processing equipment includes a reaction chamber. , The base station located in the reaction chamber, the gas shower head opposite to the base station, and the plasma induction coil structure on the side of the gas shower head away from the base station. However, the current plasma processing equipment is in the etching process However, the problem of uneven etching often occurs at different positions at the same distance from the center of the substrate.

In order to solve the above technical problems, embodiments of the present invention provide a plasma inductor coil structure, plasma processing equipment, and processing method to solve the problem that uneven etching often occurs at different positions at the same distance from the center of the substrate.

In order to solve the foregoing problems, the embodiments of the present invention provide the following technical solutions: A plasma induction coil structure, including: At least two inductance coils, each of the inductance coils includes a first part and a second part, wherein the intensity of the magnetic field generated by the first part is greater than the intensity of the magnetic field generated by the second part; The at least two inductance coils include: a first inductance coil and a second inductance coil, wherein the projection of the first part of the first inductance coil in the preset plane and the second part of the second inductance coil are in the same position. The projections in the preset plane at least partially overlap in the first direction; A first capacitor electrically connected to the first inductive coil, and a second capacitor electrically connected to the second inductive coil, at least one of the first capacitor and the second capacitor is an adjustable capacitor ； Wherein, the preset plane is the plane where the wafer is located when the inductor coil performs plasma processing on the wafer, and the first direction is the radial direction of the inductor coil.

Preferably, the output terminal of the first inductor coil is electrically connected with the first capacitor, and the output terminal of the second inductor coil is electrically connected with the second capacitor.

Preferably, the first capacitor is an adjustable capacitor, and the second capacitor is a fixed capacitor.

Preferably, the first capacitor is an adjustable capacitor, and the second capacitor is an adjustable capacitor.

Preferably, the projection of the first part of the first inductor coil on the preset plane and the projection of the second part of the second inductor coil on the preset plane are completely in the first direction. overlapping.

Preferably, the first part of the inductive coil includes a first sub-part and a second sub-part, the projection of the first sub-part in the preset plane and the second sub-part in the preset plane The projections inside overlap at least partially in the first direction.

Preferably, the second part of the inductive coil further includes a third sub-part and a fourth sub-part, the first part of the inductive coil further includes a fifth sub-part, and the fifth sub-part of the inductive coil is in the The projection in the preset plane and the projection of the first sub-portion of the inductor coil in the preset plane or the projection of the second sub-portion of the inductor coil in the preset plane are in the first The directions overlap at least partially.

Preferably, the at least two inductance coils further include a third inductance coil, the projection of the first part of the third inductance coil in the preset plane and the second part of the first inductance coil in the The projection in the preset plane and the projection of the second part of the second inductor coil in the preset plane overlap in the first direction.

Wherein, the plasma inductor coil structure further includes a third capacitor electrically connected to the third inductor coil, and the third capacitor is an adjustable capacitor.

Preferably, the projection of the first part of the first inductance coil in the preset plane, the projection of the first part of the second inductance coil in the preset plane, and the projection of the first part of the third inductance coil in the preset plane A part of the projections in the preset plane are connected end to end to form a closed loop, and the projection of the first part of the first inductance coil in the preset plane, the first part of the second inductance coil in the The projection in the preset plane and the projection of the first part of the third inductor coil in the preset plane are evenly distributed on the closed loop.

Preferably, the at least two inductance coils further include a fourth inductance coil, the projection of the first part of the fourth inductance coil in the preset plane and the second part of the first inductance coil in the The projection in the preset plane, the projection of the second part of the second inductor coil in the preset plane, and the projection of the second part of the third inductor coil in the preset plane on the first All overlap in one direction.

Wherein, the plasma inductor coil structure further includes a fourth capacitor electrically connected to the fourth inductor coil, and the fourth capacitor is an adjustable capacitor.

Preferably, the projection of the first part of the first inductance coil in the preset plane, the projection of the first part of the second inductance coil in the preset plane, and the projection of the first part of the third inductance coil in the preset plane The projection of a part in the preset plane and the projection of the first part of the fourth inductance coil in the preset plane are connected end to end to form a closed loop, and the first part of the first inductance coil is in the The projection in the preset plane, the projection of the first part of the second inductor coil in the preset plane, the projection of the first part of the third inductor coil in the preset plane, and the fourth inductor The projections of the first part of the coil in the preset plane are evenly distributed on the closed loop.

Preferably, the projection of the first part of the first inductor coil on the preset plane and the projection of the first part of the second inductor coil on the preset plane are located on the first part of the third inductor coil. A part and the first part of the fourth inductance coil are in the area enclosed by the projection in the preset plane, and the projection of the first part of the first inductance coil in the preset plane and the first part The projection of the first part of the second inductor coil in the preset plane is symmetrical along the X axis, the projection of the first part of the third inductor coil in the preset plane and the first part of the fourth inductor coil in the The projection in the preset plane is symmetrical along the Y axis, wherein the X axis is perpendicular to the Y axis.

Preferably, the voltage of the second part of the inductance coil is less than the voltage of the first part of the inductance coil, the second parts of the at least two inductance coils together form an electric field shielding ring, and the first part of the inductance coil A part is located above the electric field shield ring.

Preferably, the plasma inductor coil structure further includes a fifth capacitor and a sixth capacitor, the fifth capacitor is electrically connected to an end of the first inductor coil away from the first capacitor, and the sixth capacitor is electrically connected to One end of the second inductance coil away from the second capacitor is electrically connected.

A plasma processing equipment, which includes: Reaction chamber A gas shower head located in the reaction chamber; A plasma induction coil structure located on the side of the gas shower head away from the reaction chamber, the plasma induction coil structure being the above-mentioned plasma induction coil structure; The base is located on the side of the gas shower head away from the plasma induction coil structure, and the base is used for placing a substrate.

A plasma processing method, wherein, applied to the above-mentioned plasma processing equipment, the plasma processing method includes: Place the substrate on the base table; Performing plasma treatment on the first surface of the substrate; Based on the etching rate of different regions of the substrate, the capacitance value of at least one of the first capacitor and the second capacitor is adjusted, and the ratio of the first capacitor and the second capacitor is changed to adjust the The etching rate of the first surface of the substrate.

Compared with the conventional technology, the above technical solution has the following advantages: In the plasma induction coil structure provided by the embodiment of the present invention, the magnetic field intensity generated by the first part of the induction coil is greater than the magnetic field intensity generated by the second part of the induction coil, so that the induction coil forms an asymmetric magnetic field, Moreover, the projection of the first part of the first inductance coil included in the at least two inductance coils in the preset plane and the projection of the second part of the second inductance coil included in the at least two inductance coils in the preset plane are on the At least partially overlap in the first direction to compensate for the magnitude of the magnetic field intensity generated by the second part of the second inductive coil. At the same time, the projection of the second part of the first inductive coil on the preset plane is the same The projection of the first part of the inductor coil in the preset plane at least partially overlaps in the first direction to compensate for the magnitude of the magnetic field intensity generated by the second part of the first inductor coil. At least one of the first capacitor electrically connected to the first inductor coil and the second capacitor electrically connected to the second inductor coil is an adjustable capacitor, so that the magnetic field generated by the first part of the first inductor coil can be adjusted And/or the magnitude of the magnetic field generated by the first part of the second inductance coil. Therefore, when applied to etching, based on the etching requirements and etching conditions of the substrate surface, the first capacitor and the second capacitor can be changed. The capacitance value of at least one of the capacitors, thereby changing the ratio of the first capacitance and the second capacitance to adjust the magnetic field generated by the first part of the first inductance coil relative to the first part of the second inductance coil The size of the generated magnetic field adjusts the substrate surface to adjust the etching rate at different positions at the same distance from the center of the substrate, so that the etching rate at different positions at the same distance from the center of the substrate is more balanced, thereby increasing The uniformity of etching at different positions at the same distance from the center of the substrate surface to the center improves the unevenness of etching at different positions at the same distance from the center of the substrate surface.

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those with ordinary knowledge in the technical field without making progressive work shall fall within the protection scope of the present invention.

In the following description, many specific details are set forth in order to fully understand the present invention, but the present invention can also be implemented in other ways different from those described here. Those with ordinary knowledge in the technical field may not violate the connotation of the present invention. In the case of similar promotion, the present invention is not limited by the specific embodiments disclosed below.

As mentioned in the background art section, during the etching process of the substrate by the plasma processing equipment, the problem of uneven etching often occurs at different positions with the same distance from the center of the substrate.

The study found that during the etching process, the uneven distribution of the radio frequency field of the plasma processing equipment, the uneven distribution of the gas flow in the chamber of the reaction chamber, and the uneven distribution of the gas pressure in the chamber will cause the center of the substrate to be reached during the etching process. The phenomenon of uneven etching occurs at different positions with the same distance, that is, the phenomenon of uneven etching in the lateral direction.

In view of the above situation, the uneven distribution of the radio frequency field can be adjusted to compensate for uneven lateral etching of the wafer surface due to uneven distribution of gas flow in the cavity and uneven distribution of gas pressure in the cavity. Specifically, The plasma inductor coil structure includes a single inductor coil, and the single inductor coil can form an asymmetric magnetic field. When the wafer surface has uneven lateral etching, the asymmetry formed in the single inductor coil can be adjusted. To solve the problem of lateral unevenness on the surface of the wafer, the adjustment ability of the magnetic field of a single inductor coil is limited, which cannot solve the problem of lateral unevenness on the surface of the wafer.

Further research found that the plasma inductor coil structure can include two inductor coils, so that the overall plasma inductor coil structure generates a uniform magnetic field. When the wafer surface has uneven lateral etching, the plasma can be adjusted The level of the inductor coil structure is such that the plasma inductor coil structure generates a non-uniform magnetic field, thereby adjusting the lateral etching rate of the etching area. However, it is technically difficult to precisely control the tilting movement of the inductively coupled plasma inductor coil structure. Therefore, this method of adjusting the horizontal etching rate of the etched area by adjusting the level of the inductively coupled plasma inductor coil structure will cause problems. There are many complicated technical problems, for example, the inclination angle of the plasma inductor coil structure is not easy to accurately control.

In view of this, the embodiment of the present invention provides a plasma inductor coil structure, as shown in FIG. 1, FIG. 2, FIG. 3, FIG. 4, and FIG. 5. FIG. 1 shows an inductor provided in an embodiment of the present invention. A schematic diagram of the three-dimensional structure of the coil. FIG. 2 shows a top view of a single inductor coil provided in an embodiment of the present invention, and FIG. 3 shows the internal circuit structure of a plasma antenna coil provided in an embodiment of the present invention. Schematic diagram, FIG. 4 shows a top view of the first inductance coil and the second inductance coil provided in an embodiment of the present invention, and FIG. 5 shows the edge of the first inductance coil and the second inductance coil provided in FIG. 4 A cross-sectional view of the HH line, the plasma inductor coil structure includes: at least two inductor coils 10, each of the inductor coils 10 includes a first part (1) and a second part (2), wherein the first part (1) 1) The intensity of the generated magnetic field is greater than the intensity of the magnetic field generated by the second part (2); the at least two inductance coils 10 include: a first inductance coil 11 and a second inductance coil 12, wherein the first inductance coil 11 The projection of the first part (1) of the second inductance coil 12 in the preset plane and the projection of the second part (2) of the second inductive coil 12 in the preset plane at least partially overlap in the first direction R; and _{The first capacitor C 1} electrically connected to the first inductive coil 11 _{and the second capacitor C 2} electrically connected to the second inductive coil 12 are between the first capacitor C ₁ and the second capacitor C ₂ At least one of the capacitors is an adjustable capacitor; wherein, the preset plane is the plane where the wafer is located when the inductor coil 10 performs plasma processing on the wafer, and the first direction R is the inductor coil 10的radial.

In the embodiment of the present invention, the capacitance values of the first capacitor C ₁ and the second capacitor C ₂ initially connected to the internal circuit of the inductor coil 10 may be the same or different. Preferably, in the present invention In an embodiment, the capacitance values of the first capacitor C ₁ and the second capacitor C _{2 that are} initially connected to the internal circuit of the inductor coil 10 are the same, and it is defined that the first capacitor C _{1 is} initially connected to The capacitance value of the internal circuit of the inductor coil 10 is a preset capacitance value d. Preferably, in an embodiment of the present invention, the _{adjustment range of the first capacitor C 1} is (95%d, 105%d), Including the endpoint value, the _{adjustment range of the second capacitor C 2} is (95%d, 105%d), including the endpoint value, which is not limited by the present invention, and it depends on the situation.

It should be noted that, in the embodiment of the present invention, each of the inductor coils 10 are connected in parallel.

It should also be noted that, in an embodiment of the present invention, the radio frequency current input to the input end of each of the inductance coils 10 is the same radio frequency current. Specifically, in an embodiment of the present invention, the radio frequency current input to each of the inductance coils 10 The radio frequency currents at the input terminals are all output by the same source radio frequency circuit, where the source radio frequency circuit includes a matching circuit and a power distribution circuit for power distribution of the current output by the matching circuit. Specifically, in the embodiment of the present invention, the radio frequency currents input to different inductor coils 10 may be the same or different, which is not limited in the present invention, and it depends on the situation.

In the plasma induction coil structure provided by the embodiment of the present invention, the magnetic field intensity generated by the first part (1) of the induction coil 10 is greater than the magnetic field intensity generated by the second part (2) of the induction coil 10, so that the The inductance coil 10 forms an asymmetric magnetic field, and the first part (1) of the first inductance coil 11 included in the at least two inductance coils 10 is projected in a preset plane and the second part of the second inductance coil 12 (2) The projections in the preset plane overlap at least partially in the first direction R to compensate for the magnitude of the magnetic field intensity generated by the second part (2) of the second inductive coil 12, while the first The projection of the second part (2) of the inductor coil 11 in the preset plane and the projection of the first part (1) of the second inductor coil 12 in the preset plane are at least partially in the first direction R overlap, the size of the magnetic field strength to compensate for the second portion of the first inductive coil 11 (2) produced, and because the capacitor C and the first inductor electrically connected to the first coil 11 _a second _{At least one of the second capacitors C 2} electrically connected to the inductance coil 12 is an adjustable capacitor to adjust the magnetic field generated by the first part (1) of the first inductance coil 11 and/or the second inductance coil 12 The size of the magnetic field generated in the first part (1).

Therefore, when applied to etching, based on the etching requirements and etching conditions of the substrate surface, the capacitance value of at least one of _{the first capacitor C 1} and the second capacitor C _{2 can be changed, thereby changing the} The ratio of the first capacitor C _{1 to} the second capacitor C ₂ is used to adjust the magnetic field generated by the first part (1) of the first inductive coil 11 and/or the first part (1) of the second inductive coil 12 The size of the magnetic field adjusts the etching rate at different positions at the same distance from the surface of the substrate to the center of the substrate, so that the etching rate at different positions at the same distance from the surface of the substrate to its center is more balanced, thereby improving the lining The uniformity of etching at different positions at the same distance from the surface of the bottom to its center improves the unevenness of etching at different positions at the same distance from the surface of the substrate to its center.

Further, since the plasma inductor structure according to the present invention is provided simply by changing at least one of said first capacitance value of capacitor C ₂ and the capacitance of _the second capacitor C, changing the first capacitor C ₁ and The ratio of the second capacitor C _{2 does} not need to adjust the level of the plasma inductor coil structure to adjust the etching rate at different positions at the same distance from the center of the wafer to be processed, so that the present invention does not introduce plasma The inclination angle of the bulk inductance coil structure is difficult to control and many other complicated technical problems, so that when the plasma inductance coil structure provided by the present invention is applied, the etching rate at the same distance from the center of the wafer can be adjusted simply and conveniently. .

Further, the present invention is by varying at least one of said first capacitance value of capacitor C ₂ and the capacitance of _the second capacitor C, changes the first capacitor C ₁ and the second capacitor C ₂ ratio , In order to adjust the size of the magnetic field generated by the first part (1) of the first inductive coil 11 and/or the size of the magnetic field generated by the first part of the second inductive coil 12, so as to adjust the size of the magnetic field in different areas on the surface of the wafer. The plasma density distribution in different regions on the surface of the wafer adjusts the etching rate of the plasma inductance coil structure to the same distance from the center of the wafer at different positions, and improves the unevenness of lateral etching. Therefore, the variation range of the capacitance ratio in the present invention can be very small, so that finer magnetic field adjustment can be achieved, and the plasma inductor coil structure can be adjusted to make the plasma inductor coil structure different from its level. Uniform magnetic field, so as to adjust the etching rate in the lateral direction of the etching area, because the adjustment range of the coil is large, it is difficult to achieve the adjustment of the very small inclination, so when the magnetic field is adjusted, the amplitude of the adjusted plasma inductor coil structure is larger. , It is difficult to achieve finer amplitude adjustment.

On the basis of the above-described embodiment, the present invention, in one embodiment, the output terminal of the first inductor 11 is connected to the first end of the electric capacitance C _1, the other end of the first capacitor C _1, ground, the output terminal of the second inductor 12 and the one end of the second capacitor C ₂ electrically connected to the other end of the second capacitor C _2, in another embodiment of the present invention, the first an input inductor 11 and the first capacitor C ₁ is electrically connected to one end, the other end of the first capacitor C ₁ of the input RF current, an input terminal of said second capacitor and said second inductor 12 One end of C ₂ is electrically connected, and the _{other end of the second capacitor C 2} inputs a radio frequency current, which is not limited in the present invention, and it depends on the situation.

Below to the output terminal of the first inductor coil 11 and the first end of capacitor C ₁ is electrically connected to the output terminal of the second inductor 12 and the second capacitor C ₂ electrically connected to an end of an example. describe.

On the basis of the foregoing embodiment, in an embodiment of the present invention, the first capacitor C ₁ is an adjustable capacitor, and the second capacitor C ₂ is a fixed capacitor, so that the plasma inductor coil structure is to ensure that the first capacitor C can be _{changed. 1} and the second capacitor C ₂ ratio, it is also possible to reduce the cost of the plasma induction coil.

In another embodiment of the present invention, the first capacitor C ₁ is an adjustable capacitor, and the second capacitor C ₂ is an adjustable capacitor, so that the resistance of any capacitor can be flexibly adjusted to change the first capacitor. The ratio of C _{1 to} the second capacitor C ₂ can be used to flexibly adjust the magnetic field generated by the first part (1) of the first inductive coil 11 and/or the magnetic field generated by the first part (1) of the second inductive coil 12 By adjusting the size of the magnetic field in different areas of the wafer surface, the plasma density distribution in different areas of the wafer surface can be adjusted, thereby improving the plasma inductance coil structure to adjust the etching at different positions at the same distance from the center of the wafer Speed, improve the uneven phenomenon of lateral etching.

On the basis of the above-mentioned embodiment, in an embodiment of the present invention, the first part (1) of the inductive coil 10 includes a first sub-part a and a second sub-part c, and the second part of the inductive coil 10 (2) Including a third sub-part b, wherein the specific electrical connection structure of the first sub-part a, the second sub-part c, and the third sub-part b of the inductive coil 10 is: the first sub-part a The input terminal of the first subsection a is used to input radio frequency current, the output terminal of the first subsection a is electrically connected to the input terminal of the third subsection b, and the output terminal of the third subsection b is electrically connected to the second subsection. The input terminal of c is electrically connected. Specifically, in the embodiment of the present invention, the projection of the first sub-part a on the preset plane and the projection of the second sub-part c on the preset plane At least partially overlap in the first direction R.

On the basis of any of the foregoing embodiments, in an embodiment of the present invention, the projection of the first sub-portion a of the inductor coil 10 on the preset plane is located in the second sub-portion of the inductor coil 10 c is in the projection in the preset plane, so that the area of the etching area corresponding to the first sub-part a and the second sub-part c is also larger, so that the inductance coil 10 corresponds to The area of the area with a larger etching rate is also larger. In another embodiment of the present invention, the projection of the second sub-part c of the inductor coil 10 in the preset plane is located on the first sub-part a of the inductor coil 10 in the preset plane In the projection, the present invention does not limit this, and it depends on the situation.

It should be noted that, in the embodiment of the present invention, if the first part (1) of the inductive coil 10 only includes the first sub-part a and the second sub-part c, the second sub-part c of the inductive coil 10 The output terminal serves as the output terminal of the inductor coil 10.

On the basis of the foregoing embodiment, in an embodiment of the present invention, the shapes of the first part (1) of the inductor coil 10 and the second part (2) of the inductor coil 10 are both arc-shaped.

Preferably, in an embodiment of the present invention, the diameter of the circle where the third sub-part b of the inductor coil 10 is located may be larger than the diameter of the circle where the first sub-part a of the inductor coil 10 is located and the diameter of the second sub-part a. The diameter of the circle where the part c is located is large. In another embodiment of the present invention, the diameter of the circle where the third sub-part b of the inductor coil 10 is located may also be the same as the diameter of the first sub-part a of the inductor coil 10. The diameter of the circle is the same as at least one of the diameters of the circle in which the second sub-part c is located. In other embodiments of the present invention, the diameter of the circle in which the third sub-part b of the inductor coil 10 is located is also the same It may be located between the diameter of the circle where the first sub-part a of the inductor coil 10 is located and the diameter of the circle where the second sub-part c is located. In Figure 4, the first sub-part of the first inductive coil 11 is represented by a1, the first sub-part of the second inductive coil 12 is represented by a2, the third sub-part of the first inductive coil 11 is represented by b1, and the second inductance The third subsection of the coil 12 is denoted by b2.

On the basis of the above-mentioned embodiment, in an embodiment of the present invention, the distance between the first sub-part a and the second sub-part c included in the first part (1) of the inductive coil 10 is equal everywhere, In another embodiment of the present invention, the distance between the first sub-part a and the second sub-part c included in the first part (1) of the inductive coil 10 is not completely equal, which is not limited in the present invention. It depends on the situation.

On the basis of any of the foregoing embodiments, in an embodiment of the present invention, the projections of the first part (1) and the second part (2) of the inductive coil 10 are connected in the predetermined plane. The lines form a circle. In an embodiment of the present invention, the projection of the first part (1) and the second part (2) of the inductance coil 10 in the preset plane can also form other patterns. The present invention does not limit this, and it depends on the situation.

On the basis of any of the above-mentioned embodiments, in an embodiment of the present invention, the projection of the first part (1) of the first inductance coil 11 on the preset plane and the projection of the second inductance coil 12 The first part (1) The figure formed by the projection in the preset plane is an axisymmetric figure. Preferably, in an embodiment of the present invention, the central angle corresponding to the first part (1) of the first inductive coil 11 is 180°, and the first part (1) of the second inductive coil 12 corresponds to The central angle of is 180°, which is not limited by the present invention, and it depends on the situation.

On the basis of any of the above embodiments, in an embodiment of the present invention, as shown in FIG. 6, the magnetic field generated by the first part (1) of the first inductance coil 11 corresponds to the first etching area on the surface of the substrate A, the magnetic field generated by the first part (1) of the second inductance coil 12 corresponds to the second etching area B on the surface of the substrate. If the position in the first etching area A at the same distance from the center of the substrate is Compared with other positions at the same distance from the center of the substrate in area B, uneven etching occurs. Specifically, in an embodiment of the present invention, the first inductance coil 11 electrically connected to the first inductance coil 11 can be changed. The capacitance value of the capacitor C ₁ is used to adjust the etching rate of the first etching area A. In another embodiment of the present invention, the capacitance value _{of the second capacitor C 2 electrically connected to the second inductance coil 12 can be changed.} , To adjust the etching rate of the second etching area B, the present invention does not limit this, and it depends on the situation.

On the basis of any of the above embodiments, the projection of the first part (1) of the first inductive coil 11 in the preset plane and the second part (2) of the second inductive coil 12 in the The projection in the preset plane completely overlaps in the first direction R, that is, the projection of the first part (1) of the first inductor coil 11 in the preset plane and the second inductor coil 112 The projection of a part (1) in the preset plane does not overlap in the first direction R at all.

As shown in Figure 7, Figure 8 and Figure 9, Figure 7 shows a schematic structural diagram of the internal circuit of a plasma antenna coil provided in an embodiment of the present invention; Figure 8 shows the internal circuit provided in an embodiment of the present invention A top view of a single inductor coil; Figure 9 shows the projection of the first part (1) of the first inductor coil in the preset plane and the first part of the second inductor coil provided in an embodiment of the present invention ( 1) A schematic diagram of the arrangement of the projection in the preset plane and the projection of the first part (1) of the third inductor coil in the preset plane.

On the basis of any of the foregoing embodiments, in an embodiment of the present invention, the at least two inductance coils 10 further include a third inductance coil 13, and the first part (1) of the third inductance coil 13 is The projection in the preset plane and the projection of the second part (2) of the first inductance coil 11 in the preset plane and the second part of the second inductance coil 12 in the preset plane The projections of both overlap in the first direction R.

Wherein, the plasma inductor coil structure further includes a third capacitor C ₃ electrically connected to the third inductor coil 13, and the third capacitor C ₃ is an adjustable capacitor to be electrically connected to each inductor coil 10 by adjusting The capacitance value of the capacitor is used to adjust the current of each inductor coil 10 to adjust the size of the magnetic field generated by the first part of each inductor coil 10, thereby adjusting the size of the magnetic field in different areas of the wafer surface to adjust different areas of the wafer surface The density distribution of the plasma at the same distance from the center of the substrate is adjusted to adjust the etching rate at different positions at the same distance from the center of the substrate, so that the etching rate at different positions at the same distance from the center of the substrate is more balanced.

It should be noted that, in the embodiment of the present invention, the capacitance values of the third capacitor C ₃ and the first capacitor C ₁ and the second capacitor C ₂ initially connected to the internal circuit of the inductor 10 may be The same or different. Preferably, in an embodiment of the present invention, the third capacitor C _3, the first capacitor C ₁ and the second capacitor C _{2 are} initially connected to the inductive coil 10 The capacitance values of the internal circuits are the same. Preferably, in an embodiment of the present invention, the _{adjustment range of the third capacitor C 3} is (95%d, 105%d), including the endpoint value. The present invention does not limit this, and it depends on the situation.

It should also be noted that, in an embodiment of the present invention, the size of the first inductance coil 11 in the first direction R, the size of the second inductance coil 12 in the first direction R and the third inductance The size of the coil 13 along the first direction R may be the same. In other embodiments of the present invention, the size of the first inductor coil 11 along the first direction R and the size of the second inductor coil 12 along the first direction R The size of at least one of the inductor coils 10 along the first direction R is different from the size of the third inductor coil 13 along the first direction R. The size of the other inductor coils 10 along the first direction R The coils 10 influence each other spatially.

On the basis of any of the above-mentioned embodiments, in an embodiment of the present invention, as shown in FIG. The projection of the first part (1) of the second inductive coil 12 in the preset plane and the projection of the first part (1) of the third inductive coil 13 in the preset plane are connected end to end to form a closed Ring shape, and the projection of the first part (1) of the first inductive coil 11 in the preset plane, the projection of the first part (1) of the second inductive coil 12 in the preset plane and the projection The projection of the first part (1) of the third inductance coil 13 in the preset plane is evenly distributed on the closed loop. Preferably, in an embodiment of the present invention, the projection of the first part (1) of the first inductance coil 11 in the preset plane, and the first part (1) of the second inductance coil 12 in the The projection in the preset plane and the projection of the first part (1) of the third inductance coil 13 in the preset plane are connected end to end to form a closed ring. Specifically, in an implementation of the present invention In an example, the central angle corresponding to the first part (1) of the first inductive coil 11 is 120°, and the central angle corresponding to the first part (1) of the second inductive coil 12 is 120°. The central angle corresponding to the first part (1) of the three-inductance coil 13 is 120°, which is not limited in the present invention, and it depends on the situation.

In other embodiments of the present invention, the projection of the first part (1) of the first inductive coil 11 in the preset plane, and the first part (1) of the second inductive coil 12 in the preset plane The projection in the plane and the projection of the first part (1) of the third inductance coil 13 in the preset plane may not be located on the same closed loop, which is not limited in the present invention, and it depends on the actual situation. Certainly.

The projection of the first part (1) of the first inductor coil 11 on the preset plane, the projection of the first part (1) of the second inductor coil 12 on the preset plane and the The projection of the first part (1) of the third inductance coil 13 in the preset plane is connected end to end to form a closed loop, and the first part (1) of the first inductance coil 11 is in the preset plane. The projection, the projection of the first part (1) of the second inductive coil 12 in the preset plane and the projection of the first part (1) of the third inductive coil 13 in the preset plane are evenly distributed in the The closed loop is described as an example.

On the basis of the above-mentioned embodiment, in an embodiment of the present invention, as shown in FIG. 10, the magnetic field generated by the first part (1) of the first inductance coil 11 corresponds to the first etching area A1 on the surface of the substrate. The magnetic field generated by the first part (1) of the second inductor coil 12 corresponds to the second etched area B1 on the surface of the substrate, and the magnetic field generated by the first part (1) of the third inductor coil 13 corresponds to the third etched area C1 on the surface of the substrate. Yes, in an embodiment of the present invention, if uneven etching occurs at different positions at the same distance from the center of the substrate in different etching areas, the first part of the inductor coil 10 corresponding to the different etching areas ( 1) The capacitance value of the electrically connected capacitor is used to change the size of the radio frequency current of the first part (1) of the inductor coil 10 corresponding to the etching area where the etching area is located, thereby adjusting the etching rate of the etching area, thereby increasing the substrate The uniformity of etching at different positions at the same distance from the surface of the substrate to the center is improved to improve the uneven etching at different positions at the same distance from the surface of the substrate to the center.

It should be noted that, in the present invention, when the capacitance with the inductor is adjusted, along the first direction R, the plasma density changes more and more, and the etching rate in this direction is The magnitude of change is also getting bigger and bigger.

As shown in Figure 11, Figure 12 and Figure 13, Figure 11 shows a schematic structural diagram of the internal circuit of a plasma antenna coil provided in another embodiment of the present invention; Figure 12 shows another embodiment of the present invention A top view of a single inductor coil provided; FIG. 13 shows the projection of the first part (1) of the first inductor coil in a preset plane and the first part of the second inductor coil provided in yet another embodiment of the present invention (1) The projection in the preset plane, the first part of the third inductance coil (1) the projection in the preset plane The projection in the preset plane and the first part (1) of the fourth inductance coil 14 A schematic diagram of the arrangement of projections in the preset plane.

On the basis of any of the foregoing embodiments, in an embodiment of the present invention, the at least two inductance coils 10 further include a fourth inductance coil 14, and the first part (1) of the fourth inductance coil 14 Let the projection in the plane and the projection of the second part (2) of the first inductance coil 11 in the preset plane, the projection of the second part (2) of the second inductance coil 12 in the preset plane, and The projections of the second part (2) of the third inductance coil 13 in the preset plane overlap in the first direction.

Wherein, the plasma inductor coil structure further includes a fourth capacitor C ₄ electrically connected to the fourth inductor coil 14. The fourth capacitor C ₄ is an adjustable capacitor to be electrically connected to each inductor coil 10 by adjusting The capacitance value of the capacitor is used to adjust the current of each inductance coil 10 to adjust the size of the magnetic field generated by the first part (1) of each inductance coil 10, so as to adjust the size of the magnetic field in different areas on the surface of the wafer. The plasma density distribution of different etching areas on the surface is further adjusted to the etching rate at different positions at the same distance from the center of the substrate, so that the etching rate at different positions at the same distance from the center of the substrate is more balanced.

In other embodiments of the present invention, the at least two inductance coils 10 further include a fifth inductance coil, a sixth inductance coil and more inductance coils 10, which is not limited in the present invention, and it depends on the situation.

It should be noted that, in the embodiment of the present invention, the fourth capacitor C ₄ and the first capacitor C ₁ , the second capacitor C ₂ and the three capacitors C _{3 are} initially connected to the inductor coil 10 The capacitance value of the internal circuit can be the same or different. Preferably, in an embodiment of the present invention, the fourth capacitor C _{4 is the} same as the first capacitor C ₁ , the second capacitor C ₂ and the The capacitance value of the third capacitor C ₃ initially connected to the internal circuit of the inductor coil 10 is the same. Preferably, in an embodiment of the present invention, the _{adjustment range of the fourth capacitor C 4} is (95% d , 105%d), including the endpoint value, the present invention does not limit this, it depends on the situation.

On the basis of the above-mentioned embodiment, in an embodiment of the present invention, as shown in FIG. 13, the projection of the first part (1) of the first inductive coil 11 on the preset plane, the The projection of the first part (1) of the second inductance coil 12 in the preset plane, the projection of the first part (1) of the third inductance coil 13 in the preset plane, and the fourth inductance coil 14 The projection of the first part (1) in the preset plane is connected end to end to form a closed loop, and the projection of the first part (1) of the first inductance coil 11 in the preset plane, the The projection of the first part (1) of the second inductance coil 12 in the preset plane, the projection of the first part (1) of the third inductance coil 13 in the preset plane, and the fourth inductance coil 14 The projections of the first part (1) in the preset plane are evenly distributed on the closed ring.

On the basis of the above-mentioned embodiment, in an embodiment of the present invention, as shown in FIG. 14, the magnetic field generated by the first part (1) of the first inductance coil 11 corresponds to the first etching area A2 on the surface of the substrate, The magnetic field generated by the first part (1) of the second inductor coil 12 corresponds to the second etched area B2 on the surface of the substrate, and the magnetic field generated by the first part (1) of the third inductor coil 13 corresponds to the third etched area C2 on the surface of the substrate, The magnetic field generated by the first part (1) of the fourth inductance coil 14 corresponds to the fourth etching area D2 on the surface of the substrate. It should be noted that if uneven etching occurs in different etching areas at the same distance from the center of the substrate in different etching areas on the surface of the substrate, the first part (1) of the inductor coil 10 corresponding to the different etching areas is changed. The capacitance value of the electrically connected capacitor is used to change the magnitude of the radio frequency current of the first part (1) of the inductor coil 10 corresponding to the etching area where the etching area is located, so as to adjust the etching rate of the etching area, thereby improving the surface of the substrate The uniformity of etching at different positions at the same distance from its center improves the unevenness of etching at different positions at the same distance from the center of the substrate.

In other embodiments of the present invention, the projection of the first part (1) of the first inductive coil 11 in the preset plane, and the first part (1) of the second inductive coil 12 in the preset plane The projection in the plane, the projection of the first part (1) of the third inductance coil 13 in the preset plane and the projection of the first part (1) of the fourth inductance coil 14 in the preset plane It may not be located on the same closed loop, which is not limited in the present invention, and it depends on the situation.

Specifically, in an embodiment of the present invention, as shown in FIG. 15, the first part (1) of the first inductive coil 11 and the first part (1) of the second inductive coil 12 are in a preset plane The projection of is located in the area enclosed by the projections of the first part (1) of the third inductive coil 13 and the first part (1) of the fourth inductive coil 14 in the preset plane.

On the basis of the above-mentioned embodiment, in an embodiment of the present invention, as shown in FIG. 15, the projection of the first part (1) of the first inductance coil 11 on the preset plane and the The projection of the first part (1) of the second inductance coil 12 in the preset plane is symmetrical along the X axis, and the projection of the first part (1) of the third inductance coil 13 in the preset plane is similar to the projection of the first part (1) in the preset plane. The projection of the first part (1) of the four-inductance coil 14 in the preset plane is symmetrical along the Y axis, wherein the X axis is perpendicular to the Y axis. Preferably, in an embodiment of the present invention, the projection of the first part (1) of the first inductive coil 11 in the preset plane and the first part (1) of the second inductive coil 12 are The projections in the preset plane are connected end to end to form a closed circular ring M, and the projection of the first part (1) of the third inductor coil 13 in the preset plane and the projection of the fourth inductor coil 14 The projection of the first part (1) in the preset plane is connected end to end to form a closed circular ring N, and the circular ring M and the circular ring N share the same center.

It should be noted that when installing the inductor coils 10, under the premise that the inductor coils 10 are not in contact with each other in space, the first part (1) of the first inductor coil 11 and the The first part (1) is projected on the preset plane to form a circular ring M formed end-to-end, and the first part (1) of the third inductance coil 13 and the first part (1) of the fourth inductance coil 14 are in place. The distance between the circular ring N formed by the end-to-end connection of the projections in the preset plane is as small as possible.

On the basis of any of the foregoing embodiments, in an embodiment of the present invention, the central angle corresponding to the first part (1) of the first inductive coil 11 is 90°, and the second inductive coil 12 has a central angle of 90°. The central angle corresponding to the part (1) is 90°, the central angle corresponding to the first part (1) of the third inductive coil 13 is 90°, and the first part (1) of the fourth inductive coil 14 corresponds to The central angle of is 90°, which is not limited by the present invention, and it depends on the situation.

On the basis of the above-mentioned embodiment, in an embodiment of the present invention, as shown in FIG. 16, the magnetic field generated by the first part (1) of the first inductance coil 11 corresponds to the first etching area X1 on the surface of the substrate. , The magnetic field generated by the first part (1) of the second inductance coil 12 corresponds to the second etching area X2 on the surface of the substrate, and the magnetic field generated by the first part (1) of the third inductance coil 13 corresponds to the third etching on the surface of the substrate In the area Y1, the magnetic field generated by the first part (1) of the fourth inductance coil 14 corresponds to the fourth etching area Y2 on the surface of the substrate. Specifically, in an embodiment of the present invention, if uneven etching occurs at different positions at the same distance from the center of the substrate in different etching areas, the first part of the inductor coil 10 corresponding to the different etching areas is changed. (1) The capacitance value of the electrically connected capacitor is used to change the size of the radio frequency current of the first part of the inductor coil 10 corresponding to the etching area where the etching area is located. The uniformity of etching at different positions at the same distance from the center of the surface of the bottom to improve the unevenness of etching at different positions at the same distance from the center of the substrate.

On the basis of any of the foregoing embodiments, in an embodiment of the present invention, as shown in FIG. 17, the second part (2) of the inductance coil 10 includes a third sub-part b and a fourth sub-part d, The first part (1) also includes a fifth sub-part e. The projection of the fifth sub-part e of the inductive coil 10 in the preset plane and the first sub-part a of the inductive coil 10 are in the preset plane Or the projection of the second sub-part c of the inductive coil 10 in a preset plane, at least partially overlapping in the first direction R, so that the first part (1) of the inductive coil 10 produces The magnetic field is relatively large, so that the magnetic field generated by the first part (1) of the inductance coil 10 can be adjusted by adjusting a relatively small capacitance value.

Specifically, in an embodiment of the present invention, the specific electrical connection structure of the first part (1) and the second part (2) of the inductance coil 10 is: the input end of the first sub-part a is used for Input radio frequency current, the output end of the first sub-part a of the inductance coil 10 is electrically connected to the input end of the third sub-part b, and the output end of the third sub-part b is electrically connected to the second sub-part c The input end of the second sub-section c is electrically connected to the input end of the fourth sub-section d, and the output end of the fourth sub-section d is electrically connected to the input of the fifth sub-section e Terminals are electrically connected.

Preferably, in an embodiment of the present invention, the projection of the first sub-part a of the inductive coil 10 in a preset plane is located in the fifth sub-part e of the inductive coil 10 in the preset plane In another embodiment of the present invention, the projection of the second sub-part c of the inductive coil 10 in the preset plane is located in the fifth sub-part e of the inductive coil 10 in the preset plane In other embodiments of the present invention, the projection of the first sub-part a of the inductive coil 10 in the preset plane and the second sub-part c of the inductive coil 10 in the preset plane The projections inside are all located within the projections of the fifth sub-part e of the inductive coil 10 in the preset plane, which is not limited in the present invention, and it depends on the situation.

It should be noted that, in the embodiment of the present invention, if the first part (1) of the inductive coil 10 further includes a fifth sub-part e, the second part (2) of the inductive coil 10 includes a third sub-part b And the fourth sub-section d, the output terminal of the fifth sub-section e of the inductance coil 10 is used as the output terminal of the inductance coil 10.

It should also be noted that, in an embodiment of the present invention, the sub-parts of the inductor coil 10 are all located on the same plane, in order to save the projection of the plasma inductor coil structure in the preset plane in the first direction R The occupied area of the inductor coil 10 is not all located on the same plane. Specifically, in an embodiment of the present invention, the sub-portions of the inductor coil 10 are not located on the same plane. In another embodiment, the first part (1) and the second part (2) of the inductance coil 10 are not on the same plane, and the sub-parts of the first part (1) of the inductance coil 10 are all on the same plane In other embodiments of the present invention, the first part (1) and the second part (2) of the inductance coil 10 are not located on the same plane, and each sub-part of the second part (2) of the inductance coil 10 They are all located in the same plane, which is not limited by the present invention, and it depends on the situation.

In the following, description will be made by taking the first part (1) and the second part (2) of the inductance coil 10 not located on the same plane as an example.

On the basis of the foregoing embodiment, in an embodiment of the present invention, the first part (1) of each inductance coil 10 is located on the same side of the second part (2) of each inductance coil 10.

On the basis of any of the foregoing embodiments, in an embodiment of the present invention, the voltage of the second part (2) of the inductance coil 10 is less than the voltage of the first part (1) of the inductance coil 10. The second part (2) of at least two inductance coils 10 together form an electric field shielding ring, and the first part (1) of the inductance coil 10 is located above the electric field shielding ring. It should be noted that in the present invention In an embodiment, the subsequent plasma induction coil structure needs to be installed on the side of the gas shower head away from the reaction chamber of the plasma processing equipment, wherein the second part (2) of the induction coil 10 is close to the The gas shower head is far away from the reaction chamber, and the first part (1) of the inductor coil 10 is located on the second part (2) of the inductor coil 10 away from the gas shower head to The first part (1) of the induction coil 10 with a high voltage is kept away from the reaction chamber, thereby reducing the influence of the first part (1) of the induction coil 10 on the density distribution of the plasma in the reaction chamber.

It should also be noted that if the voltage of the second part (2) of the inductance coil 10 is less than the voltage of the first part (1) of the inductance coil 10, a standing wave needs to be formed in the inductance coil 10, and The method of forming a standing wave in the inductor coil 10 is as follows: a capacitor is electrically connected to the input end and the output end of the inductor coil 10, wherein one end of the capacitor close to the input end of the inductor coil 10 is connected to the inductor. The input end of the coil 10 is electrically connected, and the other end is used to input the radio frequency current.

In addition, in the embodiment of the present invention, the capacitor electrically connected to the input end of the inductance coil 10 can be used as a part of the source radio frequency circuit, which is not limited in the present invention, and it depends on the situation.

Based on this, on the basis of the above-mentioned embodiment, in an embodiment of the present invention, if the voltage of the second part (2) of the inductance coil 10 is less than the voltage of the first part (1) of the inductance coil 10, And the at least two inductors include a first inductor 11 and a second inductor 12, the plasma inductor coil structure further includes a fifth capacitor and a sixth capacitor, the fifth capacitor and the first inductor The end of the coil 11 away from the first capacitor C ₁ is electrically connected, and the sixth capacitor is electrically connected to the end of the second inductive coil 12 away from the second capacitor C ₂ . It should be noted that the fifth capacitor is a variable capacitor or a fixed capacitor, and the sixth capacitor is a variable capacitor or a fixed capacitor. Specifically, in one embodiment of the present invention, the fifth capacitor and the sixth capacitor are both variable capacitors. In another embodiment of the present invention, the fifth capacitor and the sixth capacitor Both are fixed capacitors. In other embodiments of the present invention, one of the fifth capacitor and the sixth capacitor is a fixed capacitor and the other is a variable capacitor. Certainly.

Specifically, in one embodiment of the present invention, if the first inductance coil 11 and the input terminal of the first capacitor C ₁ is electrically connected to one end of the other end of the first capacitor C for inputting _a radio frequency current, the input terminal of the second inductor 12 and the end of the second capacitor C ₂ electrically connected to the other end of the second capacitor C ₂ for the input RF current, the inductor 11 of the first The output end is electrically connected to one end of the fifth capacitor, the other end of the fifth capacitor is grounded, and the output end of the second inductive coil 12 is electrically connected to one end of the sixth capacitor. The other end is grounded.

In another embodiment of the present invention, if the first inductor 11 and the coil output terminal end of the first capacitor C ₁ is electrically connected to the other end of the first capacitor C _1, the second the output of the inductor 12 and the second capacitor C ₂ electrically connected to one end, the other end of the second capacitor C _2, the input terminal of the first inductor and the fifth capacitor one end of the coil 11 Electrically connected, the other end of the fifth capacitor is used to input radio frequency current, the input end of the second inductance coil 12 is electrically connected to one end of the sixth capacitor, and the other end of the sixth capacitor is grounded.

On the basis of any of the foregoing embodiments, in an embodiment of the present invention, if the voltage of the second part (2) of the inductance coil 10 is less than the voltage of the first part (1) of the inductance coil 10, and The at least two inductor coils further include a third inductor coil 13, and the plasma inductor coil structure further includes a seventh capacitor, and the seventh capacitor and the third inductor coil 13 are away from the third capacitor C ₃ One end is electrically connected. It should be noted that the seventh capacitor is a variable capacitor or a fixed capacitor.

Specifically, in one embodiment of the present invention, if the third inductor coil 13 and the input terminal of the third capacitor C ₃ is electrically connected to one end, the other end of the third capacitor C for inputting a radio frequency ₃ Current, the output terminal of the third inductor 13 is electrically connected to one end of the seventh capacitor, and the other end of the seventh capacitor is grounded. In another embodiment of the present invention, if the third inductor 13 and the output terminal of the third capacitor C ₃ is electrically connected to one end, the other end of the third capacitor C _3, then the second The input end of the three inductance coil 13 is electrically connected to one end of the seventh capacitor, and the other end of the seventh capacitor is used to input radio frequency current.

On the basis of any of the foregoing embodiments, in an embodiment of the present invention, if the voltage of the second part (2) of the inductance coil 10 is less than the voltage of the first part (1) of the inductance coil 10, and The at least two inductive coils further include a fourth inductive coil 14, and the plasma inductive coil structure further includes an eighth capacitor, and the eighth capacitor and the fourth inductive coil 14 are away from the fourth capacitor C ₄ One end is electrically connected. It should be noted that the eighth capacitor is a variable capacitor or a fixed capacitor.

Specifically, in one embodiment of the present invention, if the fourth input terminal of the inductor coil 14 and the fourth capacitor C ₄ is electrically connected to one end, the other end of the fourth capacitor C ₄ for inputting a radio frequency Current, the output terminal of the fourth inductance coil 14 is electrically connected to one end of the eighth capacitor, and the other end of the eighth capacitor is grounded. In another embodiment of the present invention, if the output of the fourth inductor coil 14 and one end of the fourth capacitor C ₄ are electrically connected, the other end of the fourth capacitor C _4, then the second The input end of the four inductance coil 14 is electrically connected to one end of the eighth capacitor, and the other end of the eighth capacitor is used to input radio frequency current.

Correspondingly, as shown in FIG. 18, the present invention also provides a plasma processing equipment, including: Reaction chamber 1; The gas shower head 2 located in the reaction chamber 1; The plasma induction coil structure 3 on the side of the gas shower head 2 away from the reaction chamber 1, the plasma induction coil structure 3 being the plasma induction coil structure 3 provided by any of the above embodiments; A base 4 located on the side of the gas shower head 2 away from the plasma induction coil structure 3, and the base 4 is used for placing a substrate.

The plasma processing apparatus provided in the embodiment, when applied to etching on the etching surface of the substrate and demand situation etching, the plasma processing apparatus of the first embodiment of the present invention is capable of and the capacitor C ₁ by changing at least a second capacitance C ₂ is the capacitance value of a capacitor, a second change ratio of the first capacitor C ₁ and the capacitor C _2, thereby adjusting the first inductor 11 of the first part (1) produced The magnetic field and/or the magnitude of the magnetic field generated by the first part (1) of the second inductive coil 12 can be used to adjust the plasma density distribution in different areas on the surface of the wafer, thereby adjusting the same distance from the center of the substrate to different positions The etching rate at the same distance from the center of the substrate surface makes the etching rate at different positions at the same distance from the center more balanced, thereby increasing the uniformity of etching at different positions at the same distance from the center of the substrate surface, and improving the surface of the substrate The phenomenon of uneven etching at different positions at the same distance from its center.

Correspondingly, as shown in FIG. 19, the present invention also provides a plasma processing method, which is applied to the plasma processing equipment provided in any of the above embodiments, and the plasma processing method includes the following steps: (S10) placed on the bottom base 4; (S20) for plasma treatment of the substrate first surface; (S30) based on the etching rate of different areas of said substrate, said first adjusting capacitor C ₁ and the The capacitance value of at least one of the second capacitors C _{2 is changed to change the ratio of the first capacitor C 1} and the second capacitor C ₂ to adjust the etching rate of the first surface of the substrate.

Embodiment of the present invention is provided a plasma processing method of the embodiment, when applied to etching on the etching surface of the substrate and demand situation etching, the plasma processing method capable of changing by the first capacitor C ₁ and the at least a second capacitance C ₂ is the capacitance value of a capacitor, a second change ratio of the first capacitor C ₁ and the capacitor C _2, thereby adjusting the first inductor 11 of the first part (1) produced The magnetic field and/or the magnitude of the magnetic field generated by the first part (1) of the second inductance coil 12 can be used to adjust the plasma density distribution in different areas of the wafer surface, thereby adjusting the same distance from the center of the substrate at different positions The etching rate of the substrate makes the etching rate at different positions at the same distance from the center of the substrate more balanced, thereby improving the uniformity of etching at different positions at the same distance from the center of the substrate, and improving the surface distance of the substrate The unevenness of etching at different positions at the same distance from the center.

It should be noted that if the capacitance value of the capacitor electrically connected to the inductance coil is larger, the radio frequency current of the first part (1) of the inductance coil 10 is larger, so that the first part (1) of the inductance coil 10 The greater the intensity of the generated magnetic field, the greater the etching rate of the etching area on the surface of the substrate corresponding to the first part (1) of the inductance coil 10; The smaller the capacitance value, the smaller the radio frequency current of the first part (1) of the inductance coil 10, so that the intensity of the magnetic field generated by the first part (1) of the inductance coil 10 is smaller, so that the first part (1) of the inductance coil 10 is The etching rate of the etching area on the surface of the substrate corresponding to a part (1) is lower.

It should also be noted that if there is a position in an etched area at the same distance from the center of the substrate as compared to a position at the same distance from the center of the substrate in other etched areas, the degree of etching is different. In an embodiment of the present invention , the plasma processing method comprising: changing a first capacitor and a second capacitor C _{C. 1} a capacitance value of the capacitance of at least ₂ in order to adjust the etching rate of the substrate surface.

On the basis of the above-mentioned embodiment, in an embodiment of the present invention, if the at least two inductance coils also include a third inductance coil, and there is a position in the etching area at the same distance from the center of the substrate as other etching areas. Compared with the positions at the same distance from the center of the substrate in the region, the etching degree is different. In an embodiment of the present invention, the plasma treatment method includes: changing the first capacitor C ₁ , the second capacitor C ₂ , at least a third capacitance value of the capacitance of the capacitor C ₃ in order to adjust the etching rate of the substrate surface.

On the basis of the above-mentioned embodiment, in an embodiment of the present invention, if there are two etching regions at the same distance from the center of the substrate with different etching degrees, then in an embodiment of the present invention, the The plasma treatment method includes: changing _{the capacitance values of at least two of the first capacitor C 1} , the second capacitor C ₂ , and the third capacitor C ₃ to adjust the etching rate of the surface of the substrate.

On the basis of the above-mentioned embodiment, in an embodiment of the present invention, if there are three etching regions at the same distance from the center of the substrate with different etching degrees, the plasma treatment method includes: The capacitance values of at least two of a capacitor C ₁ , a second capacitor C ₂ , and a third capacitor C ₃ are used to adjust the etching rate of the surface of the substrate.

On the basis of the foregoing embodiment, in an embodiment of the present invention, if the at least two inductance coils further include a fourth inductance coil, and there is a position in the etching area at the same distance from the center of the substrate as other etching areas. Compared with the positions at the same distance from the center of the substrate in the region, the etching degree is different. In an embodiment of the present invention, the plasma treatment method includes: changing the first capacitor C ₁ , the second capacitor C ₂ , The capacitance value of one of the third capacitor C ₃ and the fourth capacitor C ₄ is used to adjust the etching rate of the surface of the substrate.

On the basis of the above-mentioned embodiment, in an embodiment of the present invention, if there are two etching regions at the same distance from the center of the substrate with different etching degrees, then in an embodiment of the present invention, the The plasma processing method includes: adjusting the capacitance of at least two of the _{first capacitor C 1} , the second capacitor C ₂ , the third capacitor C ₃ and the fourth capacitor C _{4 to adjust the surface of the substrate.} Etching rate.

On the basis of the above-mentioned embodiment, in one embodiment of the present invention, if there are three etching regions at the same distance from the center of the substrate with different etching degrees, the plasma treatment method includes: changing the first The capacitance values of at least three of the capacitor C ₁ , the second capacitor C ₂ , the third capacitor C ₃ and the fourth capacitor C ₄ are used to adjust the etching rate of the surface of the substrate.

On the basis of the above-mentioned embodiment, in one embodiment of the present invention, if there are four etching areas at the same distance from the center of the substrate, the etching degree is different, then the plasma treatment method includes: changing The capacitance values of at least three of the first capacitor C ₁ , the second capacitor C ₂ , the third capacitor C ₃ and the fourth capacitor C ₄ are used to adjust the etching rate of the surface of the substrate.

The plasma inductor coil structure, plasma processing equipment, and processing method provided by the embodiments of the present invention have a magnetic field intensity generated by the first portion (1) of the inductor coil 10 greater than that generated by the second portion (2) of the inductor coil 10 The intensity of the magnetic field, so that the inductance coil 10 forms an asymmetrical magnetic field, and the first part (1) of the first inductance coil 11 included in the at least two inductance coils 10 is projected on the preset plane and the second The projection of the second part (2) of the inductance coil 12 in the preset plane at least partially overlaps in the first direction R to compensate for the intensity of the magnetic field generated by the second part (2) of the second inductance coil 12 At the same time, the projection of the second part (2) of the first inductance coil 11 in the preset plane and the projection of the first part (1) of the 12 turns of the second inductance coil in the preset plane are on the The first direction R is at least partially overlapped to compensate for the magnitude of the magnetic field intensity generated by the second part (2) of the first inductance coil 11. At least one of C _{1 and the second capacitor C 2} electrically connected to the second inductive coil 12 is an adjustable capacitor, so that the magnetic field and the magnetic field generated by the first part (1) of the first inductive coil 11 can be adjusted. /Or the magnitude of the magnetic field generated by the first part (1) of the second inductance coil 12.

Therefore, when applied to etching, based on the etching requirements and etching conditions of the surface of the substrate, _{the capacitance value of at least one of the first capacitor C 1} and the second capacitor C ₂ can be changed, thereby changing the capacitance value of the first capacitor C 1 and the second capacitor C 2. The ratio of the first capacitor C ₁ and the second capacitor C ₂ is used to adjust the magnetic field generated by the first part (1) of the first inductive coil 11 and/or the magnetic field generated by the first part (1) of the second inductive coil 12 The etching rate at different positions at the same distance from the center of the substrate is adjusted so that the etching rate at different positions at the same distance from the center of the substrate is more balanced, thereby increasing the substrate The uniformity of etching at different positions at the same distance from the surface of the substrate to the center is improved to improve the uneven etching at different positions at the same distance from the surface of the substrate to the center.

Further, since the plasma inductor structure according to the present invention is provided simply by changing at least one of said first capacitance value of capacitor C ₂ and the capacitance of _the second capacitor C, changing the first capacitor C ₁ and The ratio of the second capacitor C _{2 does} not need to adjust the level of the plasma inductor coil structure to adjust the etching rate at different positions at the same distance from the center of the wafer to be processed, so that the present invention does not introduce plasma The inclination angle of the bulk inductance coil structure is difficult to control and many other complicated technical problems, so that when the plasma inductance coil structure provided by the present invention is applied, the etching rate at different positions at the same distance from the center of the wafer can be adjusted simply and conveniently. .

Further, the present invention is by varying at least one of said first capacitance value of capacitor C ₂ and the capacitance of _the second capacitor C, changes the first capacitor C ₁ and the second capacitor C ₂ ratio , To adjust the size of the magnetic field generated by the first part (1) of the first inductor coil 11 and/or the size of the magnetic field generated by the first part (1) of the second inductor coil 12, so as to adjust the size of the magnetic field in different areas of the wafer surface , To adjust the plasma density distribution in different areas on the surface of the wafer, thereby adjusting the plasma inductance coil structure to adjust the etching rate at different positions at the same distance from the center of the wafer, thereby improving the unevenness of lateral etching. Therefore, the variation range of the capacitance ratio in the present invention can be very small, so that finer magnetic field adjustment can be achieved, and the plasma inductor coil structure can be adjusted to make the plasma inductor coil structure different from its level. Uniform magnetic field, so as to adjust the etching rate in the lateral direction of the etching area, because the adjustment range of the coil is large, it is difficult to achieve the adjustment of the very small inclination, so when the magnetic field is adjusted, the amplitude of the adjusted plasma inductor coil structure is larger. , It is difficult to achieve finer amplitude adjustment.

The various parts in this manual are described in a parallel and progressive manner. Each part focuses on the differences from other parts, and the same or similar parts between the various parts can be referred to each other.

The above description of the disclosed embodiments enables those with ordinary knowledge in the technical field to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art. The general principles defined in this document can be implemented in other embodiments without departing from the spirit or scope of the present invention. . Therefore, the present invention will not be limited to the embodiments shown in this text, but should conform to the widest scope consistent with the principles and novel features disclosed in this text.

1: reaction chamber 10: induction coil 11: first induction coil 12: second induction coil 13: third induction coil 14: fourth induction coil 2: gas shower head 3: plasma induction coil structure 4: base station A , A1, A2, X1: first etching area a: first sub-part B, B1, B2, X2: second etching area b: third sub-part C1, C2, Y1: third etching area c: second sub Part C ₁ : first capacitor C ₂ : second capacitor C ₃ : third capacitor C ₄ : fourth capacitor D2, Y2: fourth etching area d: fourth sub-part e: fifth sub-part R: first direction N, M: circular ring S10～S30: steps

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or in the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the drawings in the following description are merely For some embodiments of the present invention, for those with ordinary knowledge in the relevant technical field, other drawings can be obtained based on these drawings without making progressive labor. FIG. 1 is a schematic diagram of a three-dimensional structure of an inductor coil provided in an embodiment of the present invention; Figure 2 is a top view of a single inductor coil provided in an embodiment of the present invention; 3 is a schematic structural diagram of an internal circuit of a plasma antenna coil provided in an embodiment of the present invention; 4 is a top view of the first inductance coil and the second inductance coil provided in an embodiment of the present invention; 5 is a cross-sectional view of the first inductance coil and the second inductance coil provided in FIG. 4 along the HH line; FIG. 6 shows the magnetic field generated by the first part of the first inductor coil corresponding to the etching area A of the substrate surface and the magnetic field generated by the first part of the second inductor coil corresponding to the substrate surface provided in an embodiment of the present invention. Schematic diagram of etching area B; 7 is a schematic structural diagram of an internal circuit of a plasma antenna coil provided in another embodiment of the present invention; Fig. 8 is a top view of a single inductor coil provided in another embodiment of the present invention; 9 is a projection of the first part of the first inductor coil in the preset plane, the projection of the first part of the second inductor coil on the preset plane, and the third inductor provided in another embodiment of the present invention A schematic diagram of the arrangement of the projection of the first part of the coil in the preset plane; FIG. 10 shows the magnetic field generated by the first part of the first inductor coil corresponding to the etching area A1 on the surface of the substrate, and the magnetic field generated by the first part of the second inductor coil corresponds to the surface of the substrate in another embodiment of the present invention. A schematic diagram of the etching area B1 and the magnetic field generated by the first part of the third inductor coil corresponding to the etching area C1 on the surface of the substrate; 11 is a schematic structural diagram of an internal circuit of a plasma antenna coil provided in another embodiment of the present invention; Figure 12 is a top view of a single inductor coil provided in yet another embodiment of the present invention; FIG. 13 is a projection of the first part of the first inductor coil on the preset plane, the projection of the first part of the second inductor coil on the preset plane, and the third inductor provided in another embodiment of the present invention. A schematic diagram of the arrangement of the projection of the first part of the coil on the preset plane and the projection of the first part of the fourth inductor coil on the preset plane; FIG. 14 shows that the magnetic field generated by the first part of the first inductor coil corresponds to the etching area A2 of the substrate surface provided in another embodiment of the present invention; the magnetic field generated by the first part of the second inductor coil corresponds to the substrate surface A schematic diagram of the etching area B2, the magnetic field generated by the first portion of the third inductor coil corresponds to the etching area C2 of the substrate, and the magnetic field generated by the first portion of the fourth inductor coil corresponds to the etching area D2 of the substrate; 15 is a projection of the first part of the first inductor coil in the preset plane, the projection of the first part of the second inductor coil on the preset plane, and the third inductor provided in another embodiment of the present invention; A schematic diagram of the arrangement of the projection of the first part of the coil on the preset plane and the projection of the first part of the fourth inductor coil on the preset plane; FIG. 16 shows that the magnetic field generated by the first part of the first inductor coil corresponds to the etching area X1 of the substrate surface, and the magnetic field generated by the first part of the second inductor coil corresponds to the surface of the substrate provided in another embodiment of the present invention. The etching area X2, the etching area Y1 of the substrate corresponding to the magnetic field generated by the third inductor coil, and the etching area Y2 of the substrate surface corresponding to the magnetic field generated by the first part of the fourth inductor coil; Figure 17 is a top view of a single inductor coil provided in yet another embodiment of the present invention; 18 is a schematic structural diagram of a plasma processing equipment provided by an embodiment of the present invention; and FIG. 19 is a schematic flowchart of a plasma processing method provided by an embodiment of the present invention.

a1, a2: the first subpart

b1, b2: third subpart

Claims (16)

A plasma induction coil structure, which includes: At least two inductance coils, each of the inductance coils includes a first part and a second part, wherein the intensity of the magnetic field generated by the first part is greater than the intensity of the magnetic field generated by the second part; The at least two inductance coils include: a first inductance coil and a second inductance coil, wherein the projection of the first part of the first inductance coil in a predetermined plane and the second part of the second inductance coil The projections in the preset plane at least partially overlap in a first direction; A first capacitor electrically connected to the first inductor coil, and a second capacitor electrically connected to the second inductor coil, at least one of the first capacitor and the second capacitor is an adjustable capacitor; Wherein, the predetermined plane is a plane where the wafer is located when the inductor coil performs plasma processing on a wafer, and the first direction is a radial direction of the inductor coil. The plasma inductor coil structure according to claim 1, wherein the output terminal of the first inductor coil is electrically connected with the first capacitor, and the output terminal of the second inductor coil is electrically connected with the second capacitor. The plasma inductor coil structure according to claim 2, wherein the first capacitor is an adjustable capacitor, and the second capacitor is a fixed capacitor. The plasma inductor coil structure according to claim 2, wherein the first capacitor is an adjustable capacitor, and the second capacitor is an adjustable capacitor. The plasma induction coil structure according to claim 1, wherein the projection of the first part of the first induction coil in the preset plane and the projection of the second part of the second induction coil in the preset plane The projections completely overlap in this first direction. The plasma induction coil structure according to claim 1, wherein the first part of the induction coil includes a first sub-part and a second sub-part, the projection of the first sub-part in the preset plane and the The projections of the second sub-parts in the preset plane at least partially overlap in the first direction. The plasma induction coil structure according to claim 6, wherein the second part of the induction coil further includes a third sub-part and a fourth sub-part, and the first part of the induction coil further includes a fifth sub-part Part, the projection of the fifth sub-part of the inductive coil in the predetermined plane and the projection of the first sub-part of the inductive coil in the predetermined plane or the projection of the second sub-part of the inductive coil in the predetermined plane The projections in the preset plane at least partially overlap in the first direction. The plasma inductor coil structure according to claim 1, wherein the at least two inductor coils further include a third inductor coil, and the projection of the first part of the third inductor coil on the preset plane and the first The projection of the second part of the inductor coil on the preset plane and the projection of the second part of the second inductor coil on the preset plane overlap in the first direction; Wherein, the plasma inductor coil structure further includes a third capacitor electrically connected to the third inductor coil, and the third capacitor is an adjustable capacitor. The plasma induction coil structure according to claim 8, wherein the projection of the first part of the first induction coil in the preset plane, and the projection of the first part of the second induction coil in the preset plane And the projection of the first part of the third inductance coil in the preset plane is connected end to end to form a closed loop, and the projection of the first part of the first inductance coil in the preset plane, the second inductance coil The projection of the first part of the first part in the preset plane and the projection of the first part of the third inductor coil in the preset plane are evenly distributed on the closed loop. The plasma inductor coil structure according to claim 8, wherein the at least two inductor coils further include a fourth inductor coil, and the projection of the first part of the fourth inductor coil in the preset plane and the first The projection of the second part of the inductor coil on the preset plane, the projection of the second part of the second inductor coil on the preset plane, and the second portion of the third inductor coil on the preset plane The projections within are overlapped in the first direction; Wherein, the plasma inductor coil structure further includes a fourth capacitor electrically connected to the fourth inductor coil, and the fourth capacitor is an adjustable capacitor. The plasma induction coil structure according to claim 10, wherein the projection of the first part of the first induction coil in the preset plane, and the projection of the first part of the second induction coil in the preset plane , The projection of the first part of the third inductance coil in the preset plane and the projection of the first part of the fourth inductance coil in the preset plane are connected end to end to form a closed loop, and the first inductance coil The projection of the first part of the second inductive coil in the preset plane, the projection of the first part of the second inductive coil in the preset plane, and the projection of the first part of the third inductive coil in the preset plane and the The projection of the first part of the fourth inductance coil in the preset plane is evenly distributed on the closed loop. The plasma induction coil structure according to claim 10, wherein the projection of the first part of the first induction coil in the preset plane and the projection of the first part of the second induction coil in the preset plane Located in the area enclosed by the projection of the first part of the third inductive coil and the first part of the fourth inductive coil in the predetermined plane, and the first part of the first inductive coil is in the predetermined plane The projection inside and the projection of the first part of the second inductive coil in the preset plane are symmetrical along an X-axis, and the projection of the first part of the third inductive coil in the preset plane is symmetrical to the projection of the fourth inductive coil in the preset plane The projection of the first part of the first part in the preset plane is symmetrical along a Y axis, wherein the X axis is perpendicular to the Y axis. The plasma induction coil structure according to claim 1, wherein the voltage of the second part of the induction coil is less than the voltage of the first part of the induction coil, and the second parts of the at least two induction coils together constitute one An electric field shielding ring, and the first part of the inductance coil is located above the electric field shielding ring. The plasma inductor coil structure according to claim 13, wherein the plasma inductor coil structure further includes a fifth capacitor and a sixth capacitor, and an end of the fifth capacitor and the first inductor coil away from the first capacitor The sixth capacitor is electrically connected to an end of the second inductance coil away from the second capacitor. A plasma processing equipment, which includes: A reaction chamber; A gas shower head located in the reaction chamber; A plasma induction coil structure located on the side of the gas shower head away from the reaction chamber, the plasma induction coil structure being the plasma induction coil structure according to any one of claims 1-14; A base is located on the side of the gas shower head away from the plasma induction coil structure, and the base is used for placing a substrate. A plasma processing method, which is applied to the plasma processing equipment according to claim 15, and the plasma processing method includes the following steps: Place the substrate on the base table; Performing plasma treatment on a first surface of the substrate; Based on the etching rate of different regions of the substrate, the capacitance value of at least one of the first capacitor and the second capacitor is adjusted, and the ratio of the first capacitor and the second capacitor is changed to adjust the first capacitance of the substrate. The etching rate of the surface.

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