TWI681693B - Upper electrode element, reaction chamber and semiconductor processing device - Google Patents

Abstract

The invention provides an upper electrode element and a reaction chamber. The upper electrode element includes a coil, where n power feeding points are provided in the coil, where n is an integer greater than or equal to 1; and n+1 grounding endpoints are provided in the coil, the power feeding point and the The arrangement relationship of the grounding terminals follows the following rules: for each of the power feeding points, a grounding terminal is provided upstream and downstream of the power feeding point along the winding direction of the coil, and the power feeding point The coil between its upstream grounding terminal constitutes the first coil section, and the coil between the power feed point and its downstream grounding terminal constitutes the second coil section, the first coil section and the second coil section The part is connected in parallel between the power feed point and ground. The upper electrode element and the reaction chamber provided by the present invention can reduce the difference in potential distribution existing on the coil, thereby improving the distribution uniformity of the plasma and further improving the process uniformity.

Description

Upper electrode element, reaction chamber and semiconductor processing device

The present invention relates to the technical field of semiconductor manufacturing, and in particular, to an upper electrode element, a reaction chamber, and a semiconductor processing device.

In the semiconductor manufacturing process, Inductive Coupled Plasma (ICP, Inductive Coupled Plasma) generators can obtain high-density plasma under a low working pressure, and the structure is simple and the cost is low, so it is widely used in plasma etching (IC ), physical vapor deposition (PVD), plasma chemical vapor deposition (CVD), micro-electromechanical system (MEMS) and light-emitting diode (LED) and other processes.

During the process, in order to improve the quality of the product, before performing the deposition process, the wafer must first be pre-cleaned (Preclean) to remove impurities such as oxides on the surface of the wafer. The basic principle of the general pre-cleaning chamber is to excite the cleaning gas, such as argon, helium or hydrogen, into the plasma to form a plasma, chemically react and physically bombard the wafer, so that the surface of the wafer can be removed. Impurities.

Figure 1 is a cross-sectional view of a conventional pre-cleaning chamber. Please refer to FIG. 1, the pre-cleaning chamber includes a cavity 1, a dielectric liner 2 is provided on the top of the cavity 1, and a radio frequency coil 3 is provided around the dielectric liner 2. The radio frequency coil 3 is electrically connected to the upper radio frequency power source 5 through the upper matching device 4, and the upper radio frequency power source 5 is used to load radio frequency power to the radio frequency coil 3 and the electromagnetic field generated by the radio frequency coil 3 It can be fed into the cavity 1 through the dielectric liner 2 to excite the process gas in the cavity 1 to form a plasma. Moreover, a base 6 is also provided in the cavity 1 for carrying the wafer 7. In addition, the pedestal 6 is electrically connected to the lower RF power supply 9 through the lower matching device 8, and the lower RF power supply 9 is used to load a negative RF bias voltage to the pedestal 6 to attract plasma to etch the substrate surface.

As shown in FIG. 2, the input end of the above-mentioned radio frequency coil 3 is used as a power feeding point and is electrically connected to the upper matching device 4, and the output end of the above-mentioned radio frequency coil 3 is grounded. This has the following problems: due to the high-frequency standing wave effect, there is a large difference in the potential distribution of each turn of the RF coil 3, and there is also a large difference in the potential between the different turns of the RF coil 3, this difference This will cause the electromagnetic field generated by the radio frequency coil 3 to be unevenly distributed in the reaction chamber, resulting in a low plasma distribution uniformity, which in turn affects the process uniformity.

The present invention aims to solve at least one of the technical problems existing in the prior art, and proposes an upper electrode element and a reaction chamber, which can reduce the potential distribution difference existing on the coil, thereby improving the uniformity of the plasma distribution, and Can improve process uniformity.

To achieve the object of the present invention, an upper electrode element is provided, including a coil, where n power feeding points are provided in the coil, where n is an integer greater than or equal to 1; and n+1 ground terminals are provided in the coil Point, the arrangement relationship between the power feeding point and the grounding end point follows the following rules: for each of the power feeding points, there are respectively one upstream and downstream of the power feeding point along the winding direction of the coil The ground terminal, the coil between the power feed point and its upstream ground terminal constitutes the first coil section, and the coil between the power feed point and its downstream ground terminal constitutes the second coil section, the first A coil section and a second coil section are connected in parallel between the power feed point and ground.

Among them, the coil is a multi-turn cylindrical spiral three-dimensional coil.

For each of the power feed points, the ratio of the length of one of the first coil section and the second coil section to the total length of the sum of the two ranges from 0.5/5.5 to Between 2.5/5.5; further, the ratio of the length of one of the first coil part and the second coil part to the total length of the sum of the two ranges from 0.7/5.5 to 1.5/5.5 Further, the ratio of the length of one of the first coil part and the second coil part to the total length of the sum of the two ranges from 0.9/5.5 to 1.1/5.5. For example, the ratio of the length of one of the first coil part and the second coil part to the total length of the sum of the two is 2.5/5.5, 2.0/5.5, 1.8/5.5, 1.5/5.5, 1.4/5.5 , 1.3/5.5, 1.2/5.5, 1.1/5.5, 1.05/5.5, 1.02/5.5, 1/5.5, 0.97/5.5, 0.95/5.5, 0.9/5.5, 0.8/5.5, 0.7/5.5, 0.6/5.5 or 0.5 /5.5.

Among them, the coil is a single-turn coil.

For each of the power feeding points, at least one of the upstream ground terminal and the downstream ground terminal is grounded through the impedance configuration device, and by setting different impedance sizes of the impedance configuration device, the two The current directions of the first coil section and the second coil section are the same or opposite.

Wherein, the impedance configuration device includes an adjustable capacitor, and the capacitance of the adjustable capacitor ranges from 0 to 2000pF.

Wherein, the upper electrode element further includes a matching device and a power source, and the power source is electrically connected to the power feeding point via the matching device; and, the impedance configuration device and the matching device are integrated in the same housing or separately Set in different housings.

Wherein, the upper electrode element further includes a dielectric liner barrel, and the coil is disposed around the dielectric liner barrel around the dielectric liner barrel.

As another aspect, the present invention also provides a reaction chamber, which includes the upper electrode element according to any one of the foregoing solutions, the upper electrode element further includes a dielectric liner barrel, and the coil is disposed around the dielectric liner barrel At the periphery of the dielectric lining cylinder; the reaction chamber further includes a Faraday shield member disposed around the inside of the dielectric lining cylinder, and the Faraday shield member includes a conductive ring body, A slit is formed on the conductive ring body; the slit includes a first sub-slot, the first sub-slot is provided along the circumferential direction of the conductive ring body, and forms an angle with the axis of the conductive ring body, To increase the coupling efficiency of the electromagnetic field by increasing the coupling efficiency of the electric field component of the electromagnetic field in the circumferential direction of the conductive ring body.

Wherein, the upper end surface of the Faraday shield member is higher than the upper end surface of the dielectric liner cylinder; the lower end surface of the Faraday shield member is lower than the lower end surface of the dielectric liner cylinder.

Wherein, the reaction chamber is a pre-cleaning chamber.

As still another aspect, the present invention also provides a semiconductor processing apparatus including the reaction chamber described in any one of the foregoing solutions.

The invention has the following beneficial effects: The upper electrode element provided by the invention has a power feeding point set at a position other than the end point of the coil, and the end point of the coil is grounded to form a plurality of parallel coils from the power feeding point The division reduces the overall impedance of the coil, and accordingly, the overall voltage of the coil also decreases, which can reduce the difference in the potential distribution on the coil, improve the uniformity of the plasma distribution, and thus improve the uniformity of the process. Further, in the case where the upper electrode element includes a dielectric liner barrel, since the overall voltage of the coil is reduced, the bombardment of the dielectric liner barrel by ions in the plasma can be reduced, thereby reducing particles in the reaction chamber Pollution.

The reaction chamber and the semiconductor processing device provided by the present invention can improve the uniformity of plasma distribution by using the above-mentioned upper electrode element provided by the present invention, thereby improving the process uniformity.

In order to enable those skilled in the art to better understand the technical solution of the present invention, the upper electrode element, the reaction chamber and the semiconductor processing device provided by the present invention will be described in detail below with reference to the drawings.

Please refer to FIG. 3A, the upper electrode element provided in this embodiment includes a coil 10, and a power feed point 103 is provided on the coil 10, which is located at a division end of the coil 10 (a first end 101 and a second end 102) Outside the location. In addition, the end point of the coil 10 is grounded, and thus the coil 10 forms a plurality of parallel coil sections parallel to each other from the power feeding point 103. The radio frequency power source 12 is electrically connected to the above-mentioned power feeding point 103 through a matching device 11, and is used to load radio frequency power into the coil 10 through the power feeding point 103.

As shown in FIG. 3B, in this embodiment, the upper electrode element further includes a dielectric liner 22 through which the RF energy on the coil 10 is fed into the reaction chamber. The dielectric liner tube 22 has an annular structure, and the coil 10 is a multi-turn cylindrical spiral three-dimensional coil, and surrounds the dielectric liner tube 22. In this embodiment, the power feeding point 103 is one, and is located at a specified position of the coil 10 except the first end 101 and the second end 102, so that the coil 10 is separated from the power feeding point 103 Two coil sections are formed, specifically (refer to FIG. 3A): a first coil section 104 and a second coil section 105. The first coil section 104 is located above the power feeding point 103; the second coil section 105 is located below the power feeding point 103.

By dividing the coil 10 into two coil sections parallel to each other, the overall impedance of the coil 10 is reduced, and accordingly, the overall voltage of the coil 10 is also reduced, so that the difference in the potential distribution on the coil can be reduced, for example, The difference in the potential distribution on each turn in the coil section and the difference in potential between different turns can improve the uniformity of the electromagnetic field generated by the coil 10 in the reaction chamber, thereby improving the uniformity of the plasma distribution and improving Process uniformity. Further, in the case where the upper electrode element includes the dielectric liner 22, since the overall voltage of the coil 10 is reduced, the bombardment of the dielectric liner 22 by ions in the plasma can be reduced, thereby reducing the reaction chamber Particle pollution.

In practical applications, the distribution of the electromagnetic field generated by the coil 10 in the reaction chamber can be adjusted by changing the position of the power feed point 103 on the coil 10. The position of the power feed point 103 on the coil 10 can be changed by setting different lengths of the second coil section 105. Preferably, the total number of turns of the coil 10 is 5.5, and the length of the second coil section 105 ( The value of the ratio of the unit of turns) to the total length of the coil 10 (units of turns) ranges from 0.9/5.5 to 1.1/5.5. Using the ratio in the above range, a better uniformity of the electromagnetic field distribution can be obtained.

The following is a comparison test of the etching process using the coil in the prior art and the coil in the embodiment of the present invention, and the coil using different positions of the power feed point in the embodiment of the present invention. In this comparative test, the total number of turns of the coil 10 was 5.5.

The etching depth distribution of the wafer obtained by the etching process of the coil in the prior art is shown in FIG. 4A. On the wafer surface, the contour of the etching depth is distributed in a gradient eccentricity, so that the etching uniformity is low, generally about 3%, no Meet the process requirements (2%). In addition, the etched depth contours are distributed in a gradient eccentricity, which may cause wafer surface damage.

The coil 10 in the embodiment of the present invention is used, and the ratio of the length of the second coil section 105 to the total length of the coil 10 is 1.15/5.5, and the wafer obtained by using the coil 10 at the power feeding point 103 for the etching process The etching depth distribution is shown in FIG. 4B. The etching depth contours are still distributed in a gradient eccentricity, the etching uniformity is low, and it may cause the problem of wafer surface damage.

The coil 10 in the embodiment of the present invention is used, and the ratio of the length of the second coil section 105 to the total length of the coil 10 is 1.1/5.5 or 1.05/5.5, and the two coils at the position of the power feed point 103 are used. 10 The etching depth distribution of the wafer obtained by the etching process is shown in Figures 4C and 4D. The contours of the etching depth tend to be distributed concentrically, and the etching uniformity is improved (up to 2%), which can meet the process requirements and can Avoid damage to the wafer surface.

The coil 10 in the embodiment of the present invention is used, and the ratio of the length of the second coil section 105 to the total length of the coil 10 is 1/5.5, which is obtained by using the coil 10 at the power feed point 103 at the etching process The distribution of the etching depth of the wafer is shown in FIG. 4E, and the concentric distribution of the contours of the etching depth is better than that shown in FIGS. 4C and 4D.

In addition, in this embodiment, as shown in FIG. 3A, the first end 101 of the coil 10 is grounded through the impedance configuration device 13, and the second end 102 is directly grounded. By setting the impedance of the impedance configuration device 13, the current directions of the first coil sub-section 104 and the second coil sub-section 105 are the same or opposite. Specifically, the lower end of the first coil section 104 is grounded, and the upper end is the power feed point 103, whereby the current in the first coil section 104 flows from the power feed point 103 to the grounded lower end. If the impedance of the impedance configuration device 13 is sufficiently large, the current in the second coil section 105 flows from the upper end (ie, the first end 101) of the second coil section 105 connected to the impedance configuration device 13 toward the power feed point 103 Thus, the current directions of the first coil section 104 and the second coil section 105 are the same. Conversely, if the impedance of the impedance configuration device 13 is sufficiently small, the current in the second coil section 105 flows from the power feed point 103 toward the upper end of the second coil section 105 connected to the impedance configuration device 13, thereby, The current directions of the first coil section 104 and the second coil section 105 are opposite. Therefore, by setting the magnitude of the impedance of the impedance configuration device 13, for example, making it large enough or small enough, the current direction in the second coil section 105 can be changed.

If the current directions of the first coil section 104 and the second coil section 105 are opposite, the two electromagnetic fields generated by the first coil section 104 and the second coil section 105 cancel each other, which will The existing magnetic field strength difference is compensated, thereby further improving the uniformity of the distribution of the superimposed magnetic field formed by the above two electromagnetic fields. However, the mutual cancellation of the above two electromagnetic fields reduces the magnetic field strength of the superimposed magnetic field, thereby reducing the plasma density. Therefore, this method is suitable for processes that do not require high plasma density. For processes requiring high plasma density, the current direction of the first coil section 104 and the second coil section 105 can be the same to increase the plasma density.

The impedance configuration device 13 may include an adjustable capacitor. Before the manufacturing process, the size of the adjustable capacitor can be set according to specific needs to obtain the required impedance value, thereby improving the flexibility of impedance adjustment. The adjustable range of the above adjustable capacitor is 0~2000pF, for example, 0pF, 20pF, 50pF, 100pF, 200pF, 300pF, 500pF, 800pF, 900pF, 1000pF, 1200pF, 1500pF, 2000pF, etc.

In addition, the above-mentioned impedance arranging device 13 can determine the direction of the current, and can also make the matching device 11 easier to achieve impedance matching by selecting an appropriate impedance size. For example, when the total number of turns of the coil 10 is 5.5, and the ratio of the length of the second coil section 105 to the total length of the coil 10 is 1.1/5.5, 1.05/5.5, or 1/5.5, the capacitance value of the above adjustable capacitor may be Set within the range of 200~500pF, 200pF, 250pF, 300pF, 350pF, 400pF, 450pF, 500pF, etc., preferably 350pF.

In practical applications, the impedance configuration device 13 and the matching device 11 may be integrated in the same housing, or may be separately installed in different housings. It can be understood that the two are integrated in the same housing, which can reduce the occupied space of the device.

It should be noted that, in this embodiment, the first end 101 of the coil 10 is grounded through the impedance configuration device 13 and the second end 102 is directly grounded. However, the present invention is not limited to this. In practical applications, it is also possible to use The first end 101 of the coil 10 is directly grounded, and the second end 102 is grounded through the impedance configuration device 13; alternatively, the impedance configuration device 13 may be configured for the first end 101 and the second end 102 of the coil 10, respectively, and the impedance configuration The device 13 is grounded; alternatively, both the first end 101 and the second end 102 of the coil 10 may be directly grounded.

It should also be noted that in this embodiment, the coil 10 is a multi-turn cylindrical spiral three-dimensional coil, that is, the coil 10 extends in a spiral manner along the axis direction to form a three-dimensional structure with a contour of a cylinder. However, the present invention does not Not limited to this, in practical applications, the coil 10 may also be a single-turn coil. Whether it is a single-turn coil or a multi-turn coil, the shape of the cross section obtained by cutting the wire constituting the coil in a direction perpendicular to the axial direction of the wire is not limited, for example, trapezoidal, rectangular, square, circular, Oval and so on.

It should be further noted that, in this embodiment, the number of power feed points is one, but the present invention is not limited to this. In practical applications, the number of power feed points may also be a complex number, and different power The feeding point is located at a different position except the end point of the coil, and a grounding end point is provided between two adjacent power feeding points, that is, on the coil, corresponding to each power feeding point, The upstream end and the downstream end are provided with grounding end points, so that for each power feeding point, two coil sections connected in parallel between the power feeding point and ground are provided, so that in the coil, The number of coil sections is twice the number of power feed points. For example, there are n power feed points 103, the number of coil sections is 2n, and the number of ground terminals is n+1, where n is an integer greater than or equal to 1. The arrangement relationship between the power feeding point and the grounding terminal follows the following rules: For each power feeding point, a grounding terminal is provided upstream and downstream of the power feeding point along the winding direction of the coil Point, the coil between the power feed point and its upstream ground terminal constitutes the first coil section corresponding to the power feed point, and the coil configuration between the power feed point and its downstream ground terminal corresponds to The second coil part of the power feed point, the first coil part and the second coil part are connected in parallel between the power feed point and ground.

For example, FIG. 5 shows a structural diagram of an upper electrode element with two power feed points. As shown in FIG. 5, the upper electrode element provided in this embodiment includes a coil 10 on which a first power feeding point 1031 and a second power feeding point 1032 are provided, which are located at the upper end of the coil 10 At positions other than 101 and the lower end 1022, the upper end 101 is defined as the first end, the lower end 1022 is defined as the second end, and the winding direction of the coil 10 is from top to bottom. The first RF power supply 121 is electrically connected to the first power feed point 1031 through the first matcher 111, and the second RF power supply 122 is electrically connected to the second power feed point 1032 through the second matcher 112 for A power feeding point 1031 and a second power feeding point 1032 load the coil 10 with radio frequency power. Corresponding to the first power feeding point 1031, grounding terminals 101 and 1021 are provided upstream and downstream of the first power feeding point 1031 along the winding direction of the coil 10, respectively, and the power feeding point 1031 and its upstream grounding end The section of the coil between points 101 constitutes the first coil section, the section of the coil between the power feed point 1031 and its downstream ground terminal 1021 constitutes the second coil section, the first coil section and the second The coil section is connected in parallel between the power feed point 1031 and ground. Corresponding to the second power feed point 1032, ground terminals 1021 and 1022 are provided upstream and downstream of the second power feed point 1032 along the winding direction of the coil 10, the power feed point 1032 and its upstream ground end The section of the coil between points 1021 constitutes the first coil section, the section of the coil between the power feed point 1032 and its downstream ground terminal 1022 constitutes the second coil section, the first coil section and the second The coil section is connected in parallel between the power feed point 1032 and ground.

In the upper electrode element shown in FIG. 5, each power feed point and its corresponding two grounding terminals, the first coil section and the second coil section, and the corresponding impedance configuration device form an upper electrode Unit element, each upper electrode unit element is similar to the upper electrode element in the embodiment described above in connection with FIGS. 3A and 3B, the structure, configuration, parameter selection of each upper electrode unit element and the resulting The corresponding effects are similar to the embodiments shown in the foregoing FIGS. 3A to 4E, for example, the effect of the turns relationship between the first coil section and the second coil section corresponding to each power feed point is similar In the foregoing embodiments shown in FIGS. 3A to 4E, that is, for each power feed point, the length of one of the first coil section and the second coil section and the total length of the sum of the two The range of the ratio of degrees is preferably between 0.5/5.5 to 2.5/5.5. Further preferably, the ratio of the length of one of the first coil part and the second coil part to the total length of the sum of the two can range from 0.7/5.5 to 1.5/5.5. Further preferably, the ratio of the length of one of the first coil part and the second coil part to the total length of the sum of the two can be in the range of 0.9/5.5 to 1.1/5.5. For example, the ratio of the length of one of the first coil section and the second coil section to the total length of the sum of the two can be set to 2.5/5.5, 2.0/5.5, 1.8/5.5, 1.5/5.5, 1.4 /5.5, 1.3/5.5, 1.2/5.5, 1.1/5.5, 1.05/5.5, 1.02/5.5, 1/5.5, 0.97/5.5, 0.95/5.5, 0.9/5.5, 0.8/5.5, 0.7/5.5, 0.6/5.5 Or 0.5/5.5 to get better uniformity of electromagnetic field distribution.

It can be understood that when the number of power feeding points is more than two, a ground terminal is provided between two adjacent power feeding points, that is, the two power feeding points share a ground terminal. In fact, a plurality of ground terminals can be provided between the two power feed points. Since these ground terminals have the same potential, these ground terminals are regarded as one ground terminal. The above-mentioned understanding is also made for the grounding terminal near the coil terminal, and will not be repeated here.

It can be further understood that the coil is divided into coil sections that are twice the number of power feed points. In this way, the overall voltage of the coil is reduced, which can reduce the difference in the potential distribution on the coil and adjust the coil more finely. The distribution uniformity of the generated electromagnetic field in the reaction chamber can further improve the distribution uniformity of the plasma. In addition, for complex power feed points, each power feed point needs to be equipped with a set of matching devices and RF power supply.

In addition, it should be noted that although the foregoing embodiments have described the present invention in detail with the upper electrode element including the dielectric liner, the present invention is not limited to this. In practical applications, without affecting the quality of the process, the dielectric liner used to feed the RF energy from the coil into the reaction chamber may not be provided, but the coil is directly placed in the reaction chamber. For example, when the coil is a consumable coil (the coil itself is a sputtering target, or the material of the coil is the same as the sputtering target).

As another technical solution, as shown in FIG. 6, the present invention further provides a reaction chamber 21, which includes the upper electrode element provided by the foregoing embodiment of the present invention. The upper electrode element includes a dielectric liner 22 and a coil 10 surrounding the dielectric liner 22, wherein the dielectric liner 22 is disposed in the side wall 211 of the reaction chamber 21; the RF power supply 12 is matched by The device 11 is electrically connected to the above-mentioned power feeding point 103 on the coil 10 for loading radio frequency power into the coil 10 through the power feeding point 103. Radio frequency energy is fed into the reaction chamber 21 through the dielectric liner 22. In addition, a pedestal 24 is also provided in the reaction chamber 21. The pedestal 24 is electrically connected to the pedestal RF power supply 26 via a pedestal matching device 25. The pedestal RF power supply 26 is used to load a negative bias voltage to the pedestal 24 , To attract plasma to etch the wafer surface.

In this embodiment, the reaction chamber 21 further includes a Faraday shield 23, which is disposed around the inside of the dielectric liner 22 to protect the dielectric liner 22 from plasma etching , While avoiding the residue sputtered from the surface of the wafer to adhere to the inner wall of the dielectric liner 22 Therefore, the energy coupling efficiency of the dielectric liner 22 can be improved, and the particle pollution in the reaction chamber 21 can be reduced. In addition, the Faraday shield 23 includes a conductive ring body, and a slit is formed in the conductive ring body to prevent the Faraday shield 23 from generating eddy current loss and heat generation.

With the help of the electromagnetic shielding effect of the Faraday shield 23, the potential difference in the coil 10 can be further reduced, and the distribution of the electromagnetic field can have a secondary distribution effect, which can further improve the uniformity of the plasma distribution and improve the manufacturing process. Uniformity. In addition, due to the physical blocking effect of the Faraday shield 23, metal can be effectively prevented from being deposited on the inner wall of the dielectric liner 22, thereby avoiding a reduction in magnetic field coupling efficiency.

In this embodiment, as shown in FIG. 7, the above-mentioned slit includes a first sub-slit 232 and a second sub-slot 231, wherein the first sub-slot 232 is provided along the circumferential direction of the conductive ring body, and An angle is formed with the axis of the conductive ring body to increase the coupling efficiency of the electromagnetic field by increasing the coupling efficiency of the electric field component of the electromagnetic field in the circumferential direction of the conductive ring body. The angle formed between the first sub-slit 232 and the axis of the conductive ring body is 90°. The first sub-slots 232 are plural, and are evenly distributed along the circumferential direction of the conductive ring body. The second sub-slots 231 are provided along the axial direction of the conductive ring body, and the second sub-slots 231 are plural and are evenly distributed along the circumferential direction of the conductive ring body.

The electromagnetic field generated by the coil 10 can be divided into a magnetic field component in the axial direction of the conductive ring body and an electric field component in the circumferential direction of the conductive ring body. The axial magnetic field component of the conductive ring body can be fed into the reaction chamber 21 through the second sub-slot 231, and at the same time, the electric field component in the circumferential direction of the conductive ring body is fed into the reaction chamber through the first sub-slot 232 Inside the chamber 21, thereby increasing the overall coupling efficiency of the electromagnetic field.

It should be noted that in practical applications, only the first sub-slot 232 may be provided, and the first sub-slot 232 is inclined with respect to the axis of the conductive ring body. Preferably, the first sub-slot 232 and the The angle formed between the axes of the conductive ring body is preferably 45°. In this way, the subcomponent of the axial magnetic field component of the conductive ring body in the oblique direction of the first sub-slot 232 can be fed into the reaction chamber 21 through the first sub-slot 232, while the circumferential direction of the conductive ring body The subcomponent of the electric field component of the first subslot 232 in the inclined direction can be fed into the reaction chamber 21 through the first subslot 232.

In practical applications, the Faraday shield 23 may be grounded, or may be floating in potential. Moreover, the Faraday mask 23 may be a single-layer cylindrical structure; or may be a two-layer or more cylindrical structure formed by nesting two cylindrical structures with different diameters.

Preferably, the upper end surface of the Faraday shield member 23 is higher than the upper end surface of the dielectric liner cylinder 22; the lower end surface of the Faraday shield member 23 is lower than the lower end surface of the dielectric liner cylinder 22 to ensure the Faraday shield member 23 completely covers the inner surface of the dielectric liner 22. In addition, the inner surface of the Faraday mask 23 may be roughened by spraying or the like to prevent particles adhering to the inner surface of the Faraday mask 23 from falling off and contaminating the wafer surface.

In practical applications, the reaction chamber may be a pre-cleaning chamber.

Preferably, for the hydrogen-containing pre-cleaning process, the upper RF power supply 28 in the pre-cleaning chamber may use a lower frequency (below 13.56 MHz), such as 2 MHz, which may slow down the excitation and ionization of hydrogen atoms. Thereby reducing the heat released by the reaction of hydrogen atoms with the surface of the wafer, so that a low temperature pre-cleaning process can be realized.

In summary, the reaction chamber provided by the embodiment of the present invention can improve the uniformity of plasma distribution by using the upper electrode element provided by the above embodiment of the present invention, thereby improving the process uniformity.

As still another technical solution, the present invention also provides a semiconductor processing apparatus, which includes the reaction chamber described in the foregoing embodiments. The semiconductor processing device provided by the present invention can improve the uniformity of plasma distribution by using the above-mentioned reaction chamber provided by the present invention, thereby improving the uniformity of the process.

It can be understood that the above embodiments are merely exemplary embodiments adopted for explaining the principle of the present invention, but the present invention is not limited thereto. For those of ordinary skill in the art, various variations and improvements can be made without departing from the spirit and essence of the present invention, and these variations and improvements are also considered to be within the protection scope of the present invention.

1‧‧‧Cavity 2, 22‧‧‧‧Dielectric liner 3‧‧‧RF coil 4‧‧‧Up matching device 5‧‧‧Up RF power supply 6‧‧‧Base 7‧‧‧‧Chip 8‧ ‧‧Lower matching device 9‧‧‧Lower RF power supply 10‧‧‧Coil 11‧‧‧ Matcher 12‧‧‧RF power supply 13‧‧‧Impedance configuration device 21‧‧‧Reaction chamber 23 Faraday mask 24‧‧‧ Base 25‧‧‧ Base Matcher 26‧‧‧ Base RF power supply 101‧‧‧ First end, upper end 102‧‧‧ Second end 103‧‧‧Power feed point 104‧ ‧‧ First coil division 105‧‧‧ Second coil division 111‧‧‧ First matching device 112‧‧‧ Second matching device 122‧‧‧ Second RF power supply 121‧‧‧ First RF power supply 211‧ ‧‧Side wall 231‧‧‧Second sub-slot 232‧‧‧Second sub-slot 1021‧‧‧Ground terminal 1022‧‧‧Lower terminal 1031‧‧‧First power feed point 1032‧‧‧Second Power feed point

Figure 1 is a cross-sectional view of a conventional pre-cleaning chamber; Figure 2 is a schematic diagram of the position of a power feeding point of a radio frequency coil; Figure 3A is a structural diagram of an upper electrode element provided by an embodiment of the present invention; Figure 3B It is another structural diagram of the upper electrode element provided by the embodiment of the present invention; FIG. 4A is a wafer etching depth profile obtained by using the coil in the prior art for the etching process; FIG. 4B is a coil using the embodiment of the present invention The etching depth distribution diagram of the wafer obtained by performing the etching process; FIG. 4C is the etching depth distribution diagram of the wafer obtained by performing the etching process with another coil in the embodiment of the present invention; FIG. 4D is the adoption of yet another coil in the embodiment of the present invention The etching depth profile of the wafer obtained by performing the etching process; FIG. 4E is the etching depth profile of the wafer obtained by using another coil in the embodiment of the present invention for the etching process; FIG. 5 is the embodiment of the present invention with two powers FIG. 6 is a cross-sectional view of a reaction chamber provided by an embodiment of the present invention; FIG. 7 is a structural diagram of a Faraday shield used in an embodiment of the present invention.

10‧‧‧coil

11‧‧‧ Matcher

12‧‧‧RF power supply

13‧‧‧Impedance configuration device

101‧‧‧First

102‧‧‧The second end

103‧‧‧Power feeding point

104‧‧‧ First Coil Division

105‧‧‧Second Coil Division

Claims (14)

An upper electrode element includes a coil, characterized in that n power feeding points are provided in the coil, where n is an integer greater than or equal to 1; and n+1 grounding end points are provided in the coil, the The arrangement relationship between the power feeding point and the grounding end point follows the following rules: for each power feeding point, a grounding end point is provided upstream and downstream of the power feeding point along the winding direction of the coil , The coil between the power feed point and its upstream ground terminal constitutes a first coil section, the coil between the power feed point and its downstream ground terminal constitutes a second coil section, the first The coil section and the second coil section are connected in parallel between the power feed point and ground; for each of the power feed points, one of its upstream ground terminal and its downstream ground terminal is configured by an impedance The device is grounded, and by setting different impedance magnitudes of the impedance configuration device, the current directions of the two first coil sections and the second coil section are the same or opposite. The upper electrode element as described in item 1 of the patent application range, wherein the coil is a multi-turn cylindrical spiral three-dimensional coil. The upper electrode element as described in item 2 of the patent application scope, wherein, for each of the power feeding points, the length of one of the first coil section and the second coil section is the sum of the two The ratio of the ratio of the total length is between 0.5/5.5~2.5/5.5. The upper electrode element as described in item 3 of the patent application range, wherein the ratio of the length of one of the first coil section and the second coil section to the total length of the sum of the two ranges from 0.7 /5.5~1.5/5.5. The upper electrode element as described in item 4 of the patent application scope, wherein the ratio of the length of one of the first coil section and the second coil section to the total length of the sum of the two ranges from 0.9 /5.5~1.1/5.5. The upper electrode element according to item 3 of the patent application scope, wherein the ratio of the length of one of the first coil section and the second coil section to the total length of the sum of the two is 2.5/5.5, 2.0 /5.5, 1.8/5.5, 1.5/5.5, 1.4/5.5, 1.3/5.5, 1.2/5.5, 1.1/5.5, 1.05/5.5, 1.02/5.5, 1/5.5, 0.97/5.5, 0.95/5.5, 0.9/5.5 , 0.8/5.5, 0.7/5.5, 0.6/5.5 or 0.5/5.5. The upper electrode element as described in item 1 of the patent application range, wherein the coil is a single-turn coil. The upper electrode element as described in item 1 of the patent application range, wherein the impedance configuration device includes an adjustable capacitor, and the capacitance of the adjustable capacitor ranges from 0 to 2000 pF. The upper electrode element as described in item 1 of the patent application range, wherein the upper electrode element further includes a matcher and a power source, and the power source is electrically connected to the power feed point via the matcher; and, the The impedance configuration device and the matching device are integrated in the same casing or are respectively arranged in different casings. The upper electrode element as described in any one of claims 1 to 9, wherein the upper electrode element further includes a dielectric liner barrel, and the coil is disposed around the dielectric liner barrel in the The periphery of the dielectric liner. A reaction chamber, characterized by comprising the upper electrode element according to any one of claims 1 to 9, the upper electrode element further comprises a dielectric liner, the coil surrounds the dielectric The lining cylinder is disposed on the periphery of the dielectric lining cylinder; the reaction chamber further includes a Faraday shield member disposed around the inside of the dielectric lining cylinder, and the Faraday shield member includes A conductive ring body with a slit formed on the conductive ring body; The slot includes a first sub-slot, which is disposed along the circumferential direction of the conductive ring body and forms an angle with the axis of the conductive ring body to increase the electromagnetic field in the conductive ring The coupling efficiency of the electric field components in the circumferential direction of the body increases the overall coupling efficiency of the electromagnetic field. The reaction chamber as described in item 11 of the patent application range, wherein the upper end surface of the Faraday shield is higher than the upper end surface of the dielectric liner; the lower end surface of the Faraday shield is lower than the dielectric The lower end of the liner. The reaction chamber as described in item 11 of the patent application scope, wherein the reaction chamber is a pre-cleaning chamber. A semiconductor processing device is characterized by comprising the reaction chamber according to any one of the patent application items 11 to 13.

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