TWI521559B - Magnetic field distribution adjusting device for plasma processor and its adjusting method - Google Patents

Description

Magnetic field distribution adjusting device for plasma processor and adjusting method thereof

The present invention relates to a plasma processing technique in the field of semiconductors, and more particularly to a magnetic field distribution adjusting device, a plasma processor in which the adjusting device is mounted, and a method of adjusting a magnetic field distribution using the adjusting device.

At present, in the manufacturing process of a semiconductor device, a capacitively coupled plasma processor is used in a large amount to generate a plasma of a reactive gas, and the wafer is subjected to processing such as etching and deposition.

As shown in FIG. 1 , it is a conventional capacitively coupled plasma processor, which is provided with a pair of flat upper electrodes 2 and lower electrodes 3 in parallel at the top and bottom of the vacuum reaction chamber 1 respectively, which will need to be The etched wafer 5 is placed between the upper electrode 2 and the lower electrode 3 and supported by the susceptor 4; generally, at least one RF source is connected to the lower electrode 3, and the upper electrode 2 is grounded (or the upper and lower electrodes are respectively connected) The radio frequency source generates an RF electric field to ionize the reaction gas introduced into the reaction chamber 1 to generate a plasma 10 for etching.

However, for example, due to the introduction of reactive gases or uneven plasma distribution in the reaction chamber 1, different regions on the surface of the wafer 5 tend to have different processing rates; for different regions arranged radially along the wafer 5, this is not Uniform processing is especially noticeable, for example, to make the center area of the wafer 5 The processing rate on the wafer is faster and the processing rate on the edge regions of the wafer is slower, which results in different performance of the semiconductor devices formed in different regions on the wafer 5. This has a great impact on the process control and finished product quality of semiconductor device manufacturing. Therefore, there is an urgent need in the art for a method and apparatus that can adjust plasma uniformity.

An object of the present invention is to provide a magnetic field distribution adjusting device, an inductively coupled plasma processor in which the adjusting device is mounted, and a method of adjusting a magnetic field distribution by using the adjusting device, by generating an adjustable magnetic field of a radial distribution of the wafer, The control of the plasma radial distribution in the wafer is achieved to improve the uniformity of the etching process to different regions of the wafer surface.

In order to achieve the above object, one aspect of the present invention provides a magnetic field distribution adjusting device, and another technical solution provides a plasma processor in which the magnetic field distribution adjusting device is disposed.

Wherein, the plasma processor comprises a reaction chamber, the inside of which forms a vacuum closed space, and a pair of flat upper and lower electrodes are arranged in parallel at the top and bottom of the reaction chamber, such that one of them At least one RF source is connected to the electrode to generate a radio frequency electric field between the upper electrode and the lower electrode, and the reaction gas introduced into the reaction chamber is ionized to form a plasma, which is placed between the upper electrode and the lower electrode and supported by the base The wafer is processed.

The magnetic field distribution adjusting device comprises at least two sets of coils arranged in a center of a circle, the coil being located outside a sealed space of a reaction chamber of the plasma processor; and at least two of the same center are radially divided above the wafer and the wafer Arranging the adjustment regions such that the regions respectively surrounded by the respective coils correspond one-to-one with the positions of the respective adjustment regions distributed in the radial direction of the wafer; Preferably, each set of coils is disposed outside the reaction chamber and above the upper electrode.

Each set of coils is each coupled to a separate, current-adjustable DC power source to generate a low-frequency static magnetic field that can pass through the cavity of the reaction chamber into the vacuum side, the magnetic field passing through each set of coils being superimposed in each adjustment region With the formed composite magnetic field, the density of the plasma in the cavity is adjusted correspondingly in each adjustment region, thereby realizing the control and adjustment of the plasma distribution at different positions in the radial direction of the wafer; wherein the composite magnetic field with large composite magnetic field strength The density of the body is high, and the density of the plasma in the adjustment region where the composite magnetic field strength is small is low.

In a preferred embodiment, the adjustment region distributed along the radial direction of the wafer includes a central region and an edge region surrounding the central region; the coil arranged in a center of the circle includes the first coil and the second a coil; wherein a region enclosed by the first coil corresponds to a position of the central region, and a first DC power source DC1 with adjustable current is connected to the first coil; The area is corresponding to the position of the edge area, and a second DC power source DC2 with adjustable current is connected to the second coil.

It is assumed that a current on the first coil acts to form a magnetic field of intensity A, and a current on the second coil acts to form a magnetic field of intensity B; then when the first coil and the second coil have opposite current flows In the direction, after the two magnetic fields are superimposed, a composite magnetic field of intensity |BA| is formed in the central region, and a composite magnetic field having another intensity of |A+B| is formed in the edge region, and the composite magnetic field of the edge region is formed. The strength of the composite magnetic field is greater than the central region, so that the plasma density of the edge region is higher than that of the central region. Daughter density.

When the first coil and the second coil have the same current flow direction, the two magnetic fields are superposed, and a composite magnetic field with a strength of |A+B| is formed in the central region, and another region is formed in the edge region. A composite magnetic field of intensity |BA|, the composite magnetic field strength of the edge region is less than the composite magnetic field strength of the central region, such that the plasma density of the edge region is lower than the plasma density of the central region.

In a preferred embodiment of the plasma processor, the upper electrode is grounded; the lower electrode is connected to a first RF source RF1, and the first RF source RF1 has a first frequency for controlling ions in the reactive gas. Dissociation or plasma density; the lower electrode is further coupled to a second RF source RF2, the second RF source RF2 having a second frequency for introducing a bias voltage to control ion energy and energy distribution incident on the wafer; A frequency is greater than the second frequency.

A third technical solution of the present invention is to provide a magnetic field distribution adjusting method for a plasma processor, wherein the plasma in the reaction chamber of the plasma processor is in a radial position of the wafer by using the magnetic field distribution adjusting device of the above structure The distribution on the top is adjusted.

The magnetic field distribution adjusting method comprises: dividing a wafer and a wafer above into a plurality of regions in a radial direction; and setting at least two sets of coils of the same center on the outer side of the vacuum sealed space of the reaction chamber, and the regions enclosed by the coils are respectively Each of the adjustment regions radially divided on the wafer has a one-to-one correspondence; each of the coils is connected to a separate, current-adjustable DC power source to form a low-frequency static that can enter the vacuum side of the cavity through the reaction chamber. Magnetic field; by adjusting the current and current direction of each group of coils, so that the corresponding magnetic fields of each group of coils are superimposed, in each of the adjustments The joint region obtains the corresponding composite magnetic field intensity, and the density of the plasma in the cavity is adjusted correspondingly in each adjustment region, wherein the density of the plasma in the adjustment region with large composite magnetic field strength is high, and the plasma of the adjustment region with small composite magnetic field strength is The density of the body is low, thereby enabling control and adjustment of the plasma distribution at different locations in the radial direction of the wafer.

In a preferred embodiment, the adjustment is distributed along the radial direction of the wafer a region including a central region and an edge region surrounding the central region; the coil disposed with the center of the circle includes a first coil and a second coil; wherein an area enclosed by the first coil and the center Corresponding to the position of the area, the first coil is connected with a current-adjustable first DC power source DC1; the area enclosed by the second coil corresponds to the position of the edge region, and the second coil is Connected to a second DC power source DC2 with adjustable current; the first coil and the second coil have opposite current flow directions, and the current on the first coil acts to form a magnetic field of intensity A, by the second The current on the coil acts to form a magnetic field of intensity B. When the two magnetic fields are superimposed, a composite magnetic field of intensity |BA| is formed in the central region, and another intensity is |A+B| in the edge region. In the composite magnetic field, the composite magnetic field strength of the edge region is greater than the composite magnetic field strength of the central region, so that the plasma is concentrated from the central region toward the edge region, so as to offset the first, The plasma density is high in a central region when the second coil in the edge region of low density unevenness distribution, thereby improving plasma uniformity on the wafer radial distribution at different positions.

Compared with the prior art, the present invention applies a direct current power source to the coils arranged on the same center, so that the respective magnetic fields generated after the superposition are superimposed, and the composite magnetic fibers with different strengths can be obtained in different regions divided along the radial position of the wafer. In the field, where the area of the composite magnetic field is large, the density of the plasma is relatively higher, and in the area where the magnetic field strength is small, the density of the plasma is relatively low, thereby controlling the distribution of the radial position of the plasma on the wafer. Further, different etching treatment effects can be obtained in different regions in the radial direction on the wafer. If it is a problem that the plasma distribution is uneven due to the introduction of the reaction gas, gas discharge, etc., the size of the area enclosed by each group of coils, the direction and magnitude of the current on the coil, etc., can further pass the distribution of the composite magnetic field. To control the distribution of the plasma, thereby offsetting the original effect, so that the plasma can be evenly distributed from the center to the edge position on the wafer in the radial direction, improving the uniformity of the etching process at different positions of the wafer. Since the coil is disposed on the atmosphere side outside the vacuum sealed space of the reaction chamber, the problem that particles or other substances adhere to the coil does not occur, and therefore, the magnetic field distribution adjusting device can be conveniently applied to etching or other processing. On the plasma processor.

10‧‧‧ Plasma

1‧‧‧reaction chamber

2‧‧‧Upper electrode

3‧‧‧ lower electrode

4‧‧‧Base

5‧‧‧chip

61‧‧‧Central area

62‧‧‧Edge area

71‧‧‧First coil

72‧‧‧second coil

73‧‧‧third coil

81‧‧‧First coil

82‧‧‧second coil

91‧‧‧First coil

92‧‧‧second coil

101‧‧‧First coil

102‧‧‧second coil

A‧‧‧Intensity of magnetic field

B‧‧‧Intensity of magnetic field

|A+B|‧‧‧Intensity of composite magnetic field

|B-A|‧‧‧Intensity of composite magnetic field

|A+B-C|‧‧‧Intensity of composite magnetic field

|B-A-C|‧‧‧Intensity of composite magnetic field

|-A-B-C|‧‧‧Intensity of composite magnetic field

DC1‧‧‧ first DC power supply

DC2‧‧‧second DC power supply

RF1‧‧‧first RF source

RF2‧‧‧second RF source

1 is a schematic structural view of a conventional capacitively coupled plasma processor; FIG. 2 is a schematic diagram showing the structure of a first embodiment of a magnetic field distribution adjusting device installed in a capacitively coupled plasma processor of the present invention; 2 is a schematic plan view of the magnetic field distribution adjusting device shown in FIG. 2; FIG. 4 is a schematic view showing the structure of the second embodiment of the magnetic field distribution adjusting device of the present invention; FIG. 5 is a magnetic field distribution adjusting device of the present invention shown in FIG. FIG. 6 is a schematic view showing the structure of a third embodiment of the magnetic field distribution adjusting device of the present invention; Figure 7 is a schematic plan view showing the structure of the magnetic field distribution adjusting device shown in Figure 6; Figure 8 is a schematic view showing the structure of the fourth embodiment of the magnetic field distribution adjusting device of the present invention; Figure 9 is the magnetic field distribution adjusting of the present invention. A schematic view showing the structure of a fifth embodiment of the apparatus; and Fig. 10 is a schematic plan view showing a sixth embodiment of the magnetic field distribution adjusting apparatus of the present invention.

Specific embodiments of the present invention will be described below with reference to the accompanying drawings.

The magnetic field distribution adjusting device of the present invention can be used in a capacitively coupled plasma processor or in an inductively coupled plasma reactor. When applied to an inductively coupled plasma reactor, only a coil connected to a radio frequency power source can be placed on the insulating window, and a coil connected to a low frequency or DC power source can be placed on the insulating window, wherein the RF coil is used. To generate a plasma, a low frequency coil is used to limit the movement of the plasma to adjust the plasma concentration.

The following describes a method and an effect of the present invention by taking a capacitive coupling type plasma reactor as an example. As shown in FIG. 2, the capacitive coupling type plasma processor includes a reaction chamber 1 which can be sealed and internally Form a vacuum environment. A pair of flat upper electrodes 2 and lower electrodes 3 are arranged parallel and opposite each other, the upper electrode 2 is disposed at the top inside the reaction chamber 1, and the lower electrode 3 is disposed in a susceptor 4 at the bottom of the reaction chamber 1. A plurality of reactive gases are delivered into the reaction chamber 1; at least one RF source is coupled to one of the upper electrode 2 and the lower electrode 3, and grounded at the other electrode, or in another embodiment, The two electrodes are respectively connected to the RF source, thereby A radio frequency electric field is generated between the upper electrode 2 and the lower electrode 3, and a plasma of the reaction gas is generated, and the wafer 5 placed on the susceptor 4 is etched or the like.

For example, the upper electrode 2 can be grounded while the lower electrode 3 Connected to a higher frequency first RF source RF1 (such as 60MHz) to control ion dissociation or plasma density in the reactive gas; at the same time, a lower frequency second RF source RF2 can be connected to the lower electrode 3 ( A bias voltage is introduced, such as 2 MHz, to control the ion energy and energy distribution incident on the wafer 5. Other components in the plasma processor, such as gas introduction means, exhaust means, heating means, etc., are not shown in the drawings, and these components can be configured according to conventional means in the art.

The magnetic field distribution adjusting device of the present invention comprises at least two sets of coils arranged in the same center, and the coils are arranged outside the reaction chamber 1, that is, outside the vacuum sealed space of the reaction chamber 1 (the outside of the sealed space may be the atmospheric side), For example, it is located above the upper electrode 2, or under the lower electrode 3 (or the pedestal 4), etc., and the first case will be described below as an example. Each set of coils is each coupled to a separate DC power source to generate a static magnetic field (or slow magnetic field); the magnetic field is low frequency and its frequency should be low enough to allow the magnetic field to pass through the metal cavity of the reaction chamber 1 Enter the vacuum side and constrain the plasma therein. Since the density of the plasma is stronger in a region where the magnetic field strength is large, the density of the plasma in the region is relatively high, and in the region where the magnetic field strength is small, the density of the plasma is relatively low. Therefore, by changing the current applied to each set of coils and the positive and negative directions, the magnetic fields corresponding to the respective sets of coils can be superposed, and different magnetic field strengths can be obtained in different regions divided along the radial position of the wafer 5, and then the plasma is The distribution of the radial position on the wafer 5 is controlled.

In one embodiment shown in Figures 2 and 3, the wafer 5 is And a wafer region 5 is divided into a central region 61 and an edge region 62 surrounding the central region 61 in the radial direction, outside the reaction chamber 1, above the upper electrode 2, a region surrounded by a group of first coils 71 and the center Corresponding to the position of the region 61, a first DC power source DC1 with adjustable current is connected to the first coil 71; and a region surrounded by the second group of coils 72 is corresponding to the position of the edge region 62. A second DC power source DC2 with adjustable current is connected to the second coil 72. In Figs. 2, 4, and 6, the "fork" indicates the direction of current flowing into the paper in the coil, and the "point" indicates the direction of current flowing out of the paper in the coil, as shown in Figs. 3, 5, and 7. The direction of the current is indicated by a clockwise or counterclockwise arrow. Therefore, as can be seen from Fig. 2 and Fig. 3, in the present embodiment, the flow directions of the currents on the first coil 71 and the second coil 72 are opposite. The magnitude of the current on the first coil 71 and the second coil 72 can be adjusted to be the same or different depending on the particular application.

Then, by the action of the current on the first coil 71, a magnetic field is formed vertically in the central region 61 while being vertically downward in the edge region 62 (see the corresponding arrow in Fig. 2), and the strength of the magnetic field is set. A; by the action of the current on the second coil 72, a vertical downward magnetic field is formed in the central region 61 and the edge region 62 (see the corresponding arrow in Fig. 2), and the strength of the magnetic field is B. The two magnetic fields are superimposed to form a composite magnetic field having a strength of |BA| in the central region 61 and another composite magnetic field at the edge region 62 having an intensity of |A+B|, and therefore, the composite magnetic field strength of the edge region 62 is greater than The composite magnetic field strength of the central region 61 is such that the plasma density of the edge region 62 is higher than the plasma density of the central region 61.

That is to say, in the present embodiment, the plasma can be more concentrated from a position where the composite magnetic field strength is small (ie, the central region 61) to a position where the composite magnetic field strength is larger (ie, the edge region 62). Offset originally The problem that the density of the plasma in the central region 61 is large and the density of the edge region 62 is small is unevenly distributed due to the reaction gas delivery or uneven discharge, etc., thereby controlling the uniform distribution of the plasma in the central region 61 and the edge region 62 to improve The uniformity of the etching process at different locations in the radial direction of the wafer 5.

By adjusting the first coil 71 and the second coil 72 respectively The magnitude of the current is used to change the intensity of the respective magnetic field generated and the strength of the composite magnetic field in the corresponding region, thereby further adjusting the plasma density in different regions. Also, if the diameter of the region surrounded by the first coil 71 and/or the second region is increased or decreased, the area of the central region 61 and the edge region 62 can also be adjusted accordingly.

In one embodiment shown in Figures 4 and 5, the central area The division of the field 61, the edge region 62, the arrangement position of the first and second coils, and the like are substantially the same as those in the above embodiment, and the depiction of other components is also omitted in FIG. The difference in this embodiment is that the current directions in the first coil 71 and the second coil 72 are made the same, that is, the current by the first coil 71 acts to form the center region 61 vertically downward in the edge region. The vertical upward intensity is the magnetic field of A; and the current of the second coil 72 acts to form a magnetic field of intensity B that is vertically downward in the central region 61 and the edge region 62, and the strength of the composite magnetic field in the central region 61 For |A+B|, the strength of the composite magnetic field of the edge region 62 is |BA|, which is exactly the opposite of that in the above embodiment. Therefore, in the present embodiment, the plasma is more concentrated in the central region 61, so that the etching effect of the central region 61 is faster and the edge region 62 of the wafer 5 is slower on the wafer 5.

In the embodiment shown in Figures 6 and 7, except for the first line In addition to the central region 61 corresponding to the circle 71 and the edge region 62 corresponding to the second coil 72, a pole surrounding the edge region 62 is further provided. The edge region 63, and the region enclosed by a third coil 73 corresponds to the position of the pole edge region 63, and the third coil 73 is also connected to a third adjustable DC power source. Thereby, according to the magnetic field generated by the current action of each coil, superposition is performed in each region to form a corresponding composite magnetic field to adjust the distribution of the plasma. Taking the current direction in FIG. 6 as an example, the intensity of the composite magnetic field in the central region 61 is |A+BC|, the intensity of the composite magnetic field in the edge region 62 is |BAC|, and the strength of the composite magnetic field in the extreme edge region 63 is |-ABC|, based on the value of the magnetic field strength generated in each region, the plasma between the upper electrode 2 and the lower electrode 3 has the highest density in the region where the strength of the composite magnetic field is the highest, and the lowest in the region where the strength of the composite magnetic field is the smallest. Thus, different etching processing speeds are obtained at different positions along the radial direction of the wafer 5. According to the actual application requirements, the plasma can be evenly distributed in the central region 61 of the wafer 5, the edge region 62 to the extreme edge region 63 as the target by offsetting the influence of the original uneven distribution, and the first, second, and second are adjusted by adjustment. The three coils have the same or different current directions, and/or the current magnitude is adjusted to have the same or different values, etc. The case where more group coils and corresponding adjustment areas are set can be configured according to the description of the embodiment.

The above is set in the capacitively coupled plasma processor In any of the magnetic field distribution adjusting devices, the method for adjusting the distribution of plasma in different radial regions of the wafer 5 is as follows: the wafer 5 and the wafer 5 are divided into a plurality of regions in the radial direction; the atmosphere in the reaction chamber 1 The side, for example, above the upper electrode 2, is provided with a plurality of sets of coils of the same center, and the respective enclosed areas of the coils correspond to respective areas in the radial direction of the wafer 5, and each set of coils is respectively connected to a DC power supply whose current can be independently adjusted. By the action of the current of each set of coils, a static magnetic field of a low frequency is formed correspondingly, so that the magnetic field can penetrate the cavity and the electrode of the reaction chamber 1 to enter On the vacuum side, the plasma between the upper electrode 2 and the lower electrode 3 is restrained.

By changing the magnitude of the current applied to each set of coils and the direction of the positive and negative poles, the magnetic fields corresponding to the coils of each group are superimposed, and different magnetic fields of different intensities can be obtained in different regions divided along the radial position of the wafer 5, wherein the composite magnetic field strength In the large region, the density of the plasma is relatively higher, and in the region where the magnetic field strength is small, the density of the plasma is relatively low, thereby controlling the distribution of the plasma on the radial position on the wafer 5.

In the region where the plasma density is large, the etching process on the wafer 5 is fast, and in the region where the plasma density is small, the etching process is slow, so that it can be obtained in different regions in the radial direction on the wafer 5. Different etching treatment effects. If the plasma distribution is not uniform due to the introduction of the reaction gas or the gas discharge, the size of the area enclosed by each group of coils, the direction and size of the current on the coil, etc., can further pass the distribution of the composite magnetic field. The distribution of the plasma is controlled to counteract the original influence so that the plasma can be uniformly distributed on the wafer 5 from the center to the edge position in the radial direction, improving the uniformity of the etching process at different positions of the wafer 5.

The invention generates the original plasma distribution under the excitation of the RF electric field and is not affected by the low frequency magnetic field, and the generated ion motion is limited by the magnetic field to escape (the charged particles move in the magnetic field to form a circular motion trajectory), so the influence on the plasma concentration comes from This is achieved by reducing the diffusion of plasma to other areas. For example, the original plasma concentration distribution in a capacitively coupled plasma reactor is low in the middle high. At this time, by controlling the static magnetic field distribution, the magnetic field in the surrounding area is strong, and the plasma generated in the surrounding area cannot be diffused. Otherwise, the plasma in the central region is affected by The influence of the magnetic field is small, so more ions will diffuse into the surrounding area, so a uniform plasma concentration will eventually be achieved.

Although the content of the present invention has passed the above preferred embodiment The details are described, but it should be understood that the above description should not be construed as limiting the invention. For example, there is no fixed limit to the magnitude of the current in each of the above sets of coils, from tens of milliamps to tens of amperes, depending on how much magnetic field strength is required. For another example, the sets of coils may not be on the same horizontal plane: as in the embodiment shown in FIG. 8 (the other components in the adjusting device and the direction of the current in the coil are omitted in the figure), the lifting device may be provided. To adjust the position of the first coil 81 such that the vertical distance from the first coil 81 to the upper electrode is greater than the vertical distance from the second coil 82 to the upper electrode, the effect of this embodiment is directly in FIG. 2 or FIG. The current in the first coil 71 is reduced to be similar. Alternatively, one or more sets of coils in the device may be coils that are wound in a vertical direction rather than just a single turn: in the embodiment shown in Figure 9, the second coil 92 is a single turn coil The first coil 91 is a multi-turn coil. If other conditions are not changed, the number of turns of the coil is proportional to the strength of the magnetic field. Or alternatively, one or more sets of coils in the device may be coils that are wound in a plurality of turns in the horizontal direction rather than just a single turn: in the embodiment shown in FIG. 10, the first coil 101 has only a single turn. The second coil 102 is arranged in a spiral shape of a plurality of turns. At this time, since the currents in the spiral are in the same direction, only the magnetic field in the central region can be changed. Various modifications and alterations of the present invention will be apparent to those skilled in the art. The scope of the invention should be defined by the appended claims.

1‧‧‧reaction chamber

2‧‧‧Upper electrode

3‧‧‧ lower electrode

4‧‧‧Base

5‧‧‧chip

61‧‧‧Central area

62‧‧‧Edge area

71‧‧‧First coil

72‧‧‧second coil

A‧‧‧Intensity of magnetic field

B‧‧‧Intensity of magnetic field

|A+B|‧‧‧Intensity of composite magnetic field

|B-A|‧‧‧Intensity of composite magnetic field

DC1‧‧‧ first DC power supply

DC2‧‧‧second DC power supply

RF1‧‧‧first RF source

RF2‧‧‧second RF source

Claims (9)

A magnetic field distribution adjusting device for a plasma processor, wherein the plasma processor comprises a reaction chamber (1), and a cavity of the reaction chamber (1) forms a vacuum confined space, The top and bottom of the reaction chamber (1) are arranged in parallel with a pair of flat upper electrodes (2) and lower electrodes (3) such that at least one RF source is connected to one of the electrodes, thereby at the upper electrode (2) and A radio frequency electric field is generated between the lower electrodes (3), and a reaction gas introduced into the reaction chamber (1) is ionized to form a plasma, and is placed between the upper electrode (2) and the lower electrode (3) and is separated by A wafer (5) supported by the susceptor (4) is processed, wherein the magnetic field distribution adjusting device comprises at least two sets of coils arranged in a center of a circle, the coil being located at the sealing of the reaction chamber (1) Outside the space; the wafer (5) and the wafer (5) are radially divided by at least two adjustment regions arranged in a same center, such that the regions surrounded by the respective coils and the respective adjustment regions are One-to-one correspondence of the positions of the wafers (5) in the radial direction; each set of coils Connected from a separate, current-adjustable DC power source to generate a low-frequency static magnetic field that can pass through the cavity of the reaction chamber (1) into the vacuum side, the magnetic field of each set of coils being in each of the adjustment regions The superimposed layer forms a composite magnetic field, wherein the adjustment region radially distributed along the wafer (5) includes a central region (61) and an edge region (62) surrounding the central region (61) The coil arranged in the same center includes a first coil (71) and a second coil (72); wherein the area enclosed by the first coil (71) and the central area (61) Corresponding to the position, the first coil (71) is connected with a current-adjustable first DC power source (DC1); the second coil (72) The enclosed area corresponds to the position of the edge area (62), and the second coil (72) is connected to a current-adjustable second DC power source (DC2). The magnetic field distribution adjusting device according to claim 1, wherein the first coil (71) and the second coil (72) have opposite current flow directions; and are disposed on the first coil (71) The current acts to form a magnetic field of intensity A, and a current on the second coil (72) acts to form a magnetic field of intensity B. After the two magnetic fields are superimposed, an intensity is formed in the central region (61). a composite magnetic field of BA|, and another composite magnetic field having an intensity of |A+B| is formed in the edge region (62), and the composite magnetic field strength of the edge region (62) is greater than the composite of the central region (61) The magnetic field strength is such that the plasma density of the edge region (62) is higher than the plasma density of the central region (61). The magnetic field distribution adjusting device according to claim 1, wherein the first coil (71) and the second coil (72) have the same current flow direction; and are disposed on the first coil (71) The current acts to form a magnetic field of intensity A, and a current on the second coil (72) acts to form a magnetic field of intensity B. After the two magnetic fields are superimposed, an intensity is formed in the central region (61). a composite magnetic field of A+B|, and a composite magnetic field of another intensity |BA| is formed in the edge region (62), and the composite magnetic field strength of the edge region (62) is smaller than the composite of the central region (61) The magnetic field strength is such that the plasma density of the edge region (62) is lower than the plasma density of the central region (61). The magnetic field distribution adjusting device according to claim 1, wherein each group of coils is disposed outside the reaction chamber (1) and above the upper electrode (2). A plasma processor provided with the magnetic field distribution adjusting device according to claim 1, wherein the plasma processor includes a reaction chamber (1), and a cavity of the reaction chamber (1) forms a vacuum seal a space in which a pair of flat upper electrodes (2) and the lower electrode (3) are disposed in parallel at the top and bottom of the reaction chamber (1) such that at least one RF source is connected to one of the electrodes, thereby Generating a radio frequency electric field between the upper electrode (2) and the lower electrode (3), ionizing a reaction gas introduced into the reaction chamber (1) to form a plasma, and placing the upper electrode (2) and the lower electrode (3) processing the wafer (5) supported by the susceptor (4); the plasma processor is further provided with a magnetic field distribution adjusting device including the reaction chamber (1) At least two sets of coils arranged on the outer side of the confined space are arranged in a center; the wafer (5) and the wafer (5) are radially divided by at least two adjustment regions arranged in a same center, so that the coils are respectively surrounded by And the respective adjustment area in the radial direction of the wafer (5) The positions of the distributions correspond one-to-one; each set of coils is each connected to a separate, current-adjustable DC power source to generate a low-frequency static magnetic field that can pass through the cavity of the reaction chamber (1) and enter the vacuum side. The composite magnetic field formed by the magnetic field of the group coil superimposed in each adjustment region adjusts the density of the plasma in the cavity in each adjustment region, thereby realizing plasma in different positions in the radial direction of the wafer (5). Body distribution is controlled and adjusted. A plasma processor according to claim 5, wherein said adjustment region radially distributed along said wafer (5) comprises a central region (61) and surrounding said central region (61) The side a rim region (62); the coil arranged in the same center includes a first coil (71) and a second coil (72); wherein the area enclosed by the first coil (71) and the Corresponding to the position of the central area (61), the first coil (71) is connected to a current-adjustable first DC power source (DC1); the area enclosed by the second coil (72) is Corresponding to the position of the edge region (62), a second DC power source (DC2) with adjustable current is connected to the second coil (72); the first coil (71) and the second coil (72) has the same or opposite current flow direction. The plasma processor of claim 5 or 6, wherein each set of coils is disposed outside the reaction chamber (1) above the upper electrode (2). The plasma processor of claim 5, wherein the upper electrode (2) is grounded; the lower electrode (3) is connected to a first RF source (RF1), the first RF source (RF1) Having a first frequency for controlling ion dissociation or plasma density in the reactive gas; the lower electrode (3) is also coupled to the second RF source (RF2), the second RF source (RF2) having a a second frequency for introducing a bias voltage to control ion energy and energy distribution incident on the wafer (5); wherein the first frequency is greater than the second frequency. A magnetic field distribution adjusting method for a plasma processor, wherein the plasma in a reaction chamber (1) of the plasma processor is at a radial position of the wafer by using the magnetic field distribution adjusting device of claim 1 The distribution is adjusted, wherein the magnetic field distribution adjustment method comprises: dividing a wafer (5) and the wafer (5) into a plurality of regions in a radial direction; in the reaction chamber (1) The outer side of the vacuum confined space is provided with at least two sets of coils of the same center, and the respective enclosed areas of the coils are in one-to-one correspondence with the respective adjustment areas radially divided on the wafer (5); each set of coils is independent of each other, A current-adjustable DC power source is connected to form a low-frequency static magnetic field that can enter the vacuum side through a cavity of the reaction chamber (1); each group of coils is adjusted by adjusting the current magnitude and current direction of each set of coils After the corresponding magnetic fields are superimposed, the corresponding composite magnetic field strength is obtained in each of the adjustment regions, and the density of the plasma in the cavity is adjusted correspondingly in the respective adjustment regions, wherein the composite magnetic field has a large adjustment region plasma. The density of the plasma in the adjustment region where the density of the composite magnetic field is small is low, so that the plasma distribution at different positions in the radial direction of the wafer (5) is controlled and adjusted, wherein the wafer (5) is radially distributed along the wafer. The adjustment area includes a central area (61) and an edge area (62) surrounding the central area (61); The coil includes a first coil (71) and a second coil (72); wherein a region enclosed by the first coil (71) and a position of the central region (61) Correspondingly, a first DC power source (DC1) with adjustable current is connected to the first coil (71); a region enclosed by the second coil (72) and the edge region (62) Corresponding to the position, the second coil (72) is connected to a current-adjustable second DC power source (DC2); the first coil (71) and the second coil (72) have opposite currents. The flow direction is such that a current on the first coil (71) acts to form a magnetic field of intensity A, and a current on the second coil (72) acts to form a magnetic field of intensity B, and the two magnetic fields are superimposed. After the center The region (61) forms a composite magnetic field of intensity |BA|, and a composite magnetic field of another intensity |A+B| is formed in the edge region (62), and the composite magnetic field strength of the edge region (62) a composite magnetic field strength greater than the central region (61) such that plasma is concentrated from the central region (61) toward the edge region (62) to counteract plasma in the central region when the first and second coils are not disposed ( 61) A non-uniform distribution state in which the density is high and the density in the edge region (62) is low, thereby improving the uniformity of plasma distribution on different positions in the radial direction on the wafer (5).