Upper electrode structure and semiconductor process equipment

Abstract

This application discloses an upper electrode structure and semiconductor manufacturing equipment. The upper electrode structure includes a first housing, a second housing, and a capacitance adjustment device. The second housing is disposed within the first housing, and a gap exists between the first and second housings. The capacitance adjustment device is disposed in the gap and is used to adjust the capacitance of a local area between the first and second housings. Since radio frequency (RF) energy within the second housing is transferred to the first housing via capacitive coupling, the amount of RF energy transferred also changes in the region where the capacitance of the first and second housings varies. Therefore, by controlling the amount of RF energy transferred, the uniformity of RF energy within the second housing can be adjusted, thereby improving process uniformity and ensuring the yield rate of the semiconductor manufacturing process.

Description

[Technical Field]

[0001] This application relates to the field of semiconductor manufacturing technology, and in particular to an upper electrode structure and semiconductor process equipment. [Previous Technology]

[0002] Semiconductor processes such as coating and etching are commonly used methods in semiconductor manufacturing. During coating and etching processes, radio frequency (RF) energy is fed into the process space using an upper electrode to ionize the process gas within the space. The uniformity of the RF energy feed is a critical issue, significantly impacting the uniformity of the process.

[0003] However, the current top electrode structure has a problem of poor uniformity in feeding radio frequency energy, especially high frequency (e.g., 40.68MHz, 60.36MHz, etc.) radio frequency energy, which will affect the uniformity of plasma distribution in the process space, and thus affect the uniformity of the process, resulting in a decrease in the yield of semiconductor manufacturing process. [Summary of the Invention]

[0004] This application discloses an upper electrode structure and semiconductor manufacturing equipment to solve the problem that the upper electrode in the related technology cannot fully meet the requirement of uniform feeding of radio frequency energy.

[0005] To solve the above-mentioned technical problems, this application is implemented as follows: Firstly, embodiments of this application disclose an upper electrode structure, which includes a first housing, a second housing, and a capacitance adjustment device; the second housing is disposed within the first housing, and a gap exists between the first housing and the second housing; the capacitance adjustment device is disposed in the gap and is used to adjust the capacitance of a local area between the first housing and the second housing. Secondly, embodiments of this application disclose a semiconductor process apparatus, which includes a radio frequency power supply, a reaction chamber, and the above-mentioned upper electrode structure; the radio frequency power supply is electrically connected to the upper electrode structure, and the reaction chamber is disposed below the upper electrode structure.

[0006] The technical solution adopted in this application can achieve the following technical effects: The upper electrode structure disclosed in the embodiments of this application improves the related technology. The disclosed upper electrode structure includes a first housing, a second housing, and a capacitance adjustment device. The second housing is disposed inside the first housing, and there is a gap between the first housing and the second housing. The capacitance adjustment device is disposed in the gap and is used to adjust the capacitance of a local area between the first housing and the second housing. When there is a problem with the uniformity of radio frequency energy in the second housing, the capacitance adjustment device can be used to adjust the capacitance of a local area between the first housing and the second housing. Since the radio frequency energy in the second housing is transferred to the first housing through capacitive coupling, and a portion of the radio frequency energy is transferred to the outside through the first housing, the amount of radio frequency energy transferred will also change in the area where the capacitance of the first housing and the second housing changes. Therefore, the uniformity of radio frequency energy in the second housing can be adjusted by controlling the amount of radio frequency energy transferred, thereby improving the uniformity of the process and ensuring the yield of the semiconductor manufacturing process.

Implementation Method

[0008] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0009] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and are not used to describe a specific order or sequence. It should be understood that such terms can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and do not limit the number of objects; for example, the first object can be one or more.

[0010] The technical solutions disclosed in the various embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0011] Semiconductor processes such as coating and etching are crucial steps in wafer fabrication. During these processes, an upper electrode is used to feed radio frequency (RF) energy into the process space to ionize the process gas. However, the upper electrode in related technologies is affected by the distribution of internal components, leading to poor uniformity in the RF energy feeding process. This affects the uniformity of plasma distribution within the process space, consequently impacting process uniformity and resulting in a decrease in wafer yield.

[0012] Based on the above, please refer to Figures 1 to 14. This application discloses an upper electrode structure, which may include a first housing 110 and a second housing 120. The size of the first housing 110 is larger than the size of the second housing 120. The second housing 120 is disposed within the first housing 110, and there is a gap between the first housing 110 and the second housing 120. The second housing 120 is used to connect to a radio frequency (RF) power supply. Taking a physical vapor deposition (PVD) device as an example, to improve the sputtering rate, a DC power supply can be connected simultaneously with the RF power supply, forming an RF-DC power supply. The first housing 110 is used to protect the second housing 120 and also provides a shielding effect, preventing the magnetic and electric fields inside the second housing 120 from affecting the external environment. Those skilled in the art should understand that the upper electrode structure of this application is not limited to PVD devices, but can also be applied to any semiconductor process equipment that requires adjustment of the uniformity of RF energy feed, such as CCP (Capacitively Coupled Plasma) devices.

[0013] The radio frequency energy generated by the radio frequency power supply can be fed into the second housing 120 through the conductive pillar 140, and is distributed in a diffuse manner within the second housing 120, and fed into the target material 160. A reaction chamber 200 is provided below the upper electrode structure. The radio frequency energy fed into the second housing 120 can ionize the process gas in the reaction chamber 200 into plasma. Under the action of magnetic and electric fields, the plasma will move with greater kinetic energy. Taking the PVD process as an example, as shown in Figure 1, the plasma will bombard the target material 160 below the second housing 120, causing the atoms on the surface of the target material 160 to detach from the original lattice and deposit onto the surface of the wafer to form a thin film. The first housing 110 can be connected to a reference level, such as ground. There is a gap between the inner wall of the first housing 110 and the outer wall of the second housing 120. The second housing 120 can transfer radio frequency energy to the first housing 110 by capacitive coupling, thereby changing the amount of radio frequency energy in the second housing 120. The radio frequency energy transferred to the first housing 110 can be discharged by grounding.

[0014] In the above-mentioned process, the uniformity of the distribution of radio frequency energy generated by the radio frequency power supply within the second housing 120 directly affects the uniformity of plasma distribution within the reaction chamber 200, and thus affects the uniformity of the process. As shown in Figures 1 and 5, due to the relatively complex internal structure of the second housing 120, it usually contains many components, such as motors, magnetrons, inlet and outlet water pipes, filter boxes, etc., and these components cannot be perfectly symmetrical during installation. This results in poor uniformity of radio frequency energy feeding into the second housing 120, which in turn affects the uniformity of plasma distribution within the second housing 120.

[0015] Based on the above, in this embodiment of the application, as shown in FIG1, the upper electrode structure may further include a capacitance adjustment device 130. The capacitance adjustment device 130 is disposed in the gap between the first housing 110 and the second housing 120. The capacitance adjustment device 130 can adjust the capacitance of a local area between the inner wall of the first housing 110 and the outer wall of the second housing 120.

[0016] Specifically, the inner wall of the first housing 110 and the outer wall of the second housing 120 can be approximated as a parallel-plate capacitor. A portion of the radio frequency energy within the second housing 120 can be transferred to the first housing 110 and the outside via capacitive coupling, causing a change in the radio frequency energy within the second housing 120. When uneven energy feed occurs in a certain region within the second housing 120 (for ease of description later, this region can be defined as the first region), the capacitance between the first housing 110 and the second housing 120 corresponding to the first region can be adjusted accordingly. By controlling the amount of radio frequency energy transferred in the first region, the radio frequency energy in the first region and other regions within the second housing 120 can be kept uniformly distributed.

[0017] In the specific adjustment process, if the radio frequency energy of the first region is higher than that of other regions in the second housing 120, the capacitance between the first housing 110 and the second housing 120 corresponding to the first region can be increased. The increased capacitance makes the first region more capable of transmitting radio frequency energy. Therefore, more radio frequency energy in the first region will be transmitted to the first housing 110 and the outside through capacitive coupling, thereby reducing the radio frequency energy in the first region. This makes the radio frequency energy of the first region and other regions in the second housing 120 uniformly distributed, thereby enabling the plasma in the reaction chamber 200 to be uniformly distributed.

[0018] It should be added that if the radio frequency energy of the first region is lower than that of other regions in the second housing 120, the capacitance between the first housing 110 and the second housing 120 corresponding to the first region can also be reduced. The reduction in capacitance weakens the ability of the first region to transfer radio frequency energy. Therefore, less radio frequency energy will be transferred to the first housing 110 in the first region, thereby increasing the radio frequency energy of the first region and maintaining a uniform distribution with the radio frequency energy of other regions in the second housing 120, so that the plasma in the reaction chamber 200 can be kept uniformly distributed.

[0019] By increasing or decreasing the capacitance between the first housing 110 and the second housing 120 as described above, the uniformity of plasma distribution within the reaction chamber 200 can be adjusted. The capacitance adjustment device 130 can be disposed on the inner wall of the first housing 110, with the first housing 110 and the capacitance adjustment device 130 in contact with each other; the capacitance adjustment device 130 can also be disposed on the outer wall of the second housing 120, with the second housing 120 in contact with each other; a support structure can also be provided between the first housing 110 and the second housing 120 to mount the capacitance adjustment device 130, in which case the capacitance adjustment device 130 and the first housing 110 and the second housing 120 can be in a non-contact relationship. The capacitance adjustment device 130 can adjust the capacitance of different regions between the first housing 110 and the second housing 120 by switching its own position, thereby adjusting the amount of radio frequency energy transferred in the corresponding region according to the distribution of radio frequency energy within the second housing 120, so that the radio frequency energy is uniformly distributed within the second housing 120.

[0020] It should be noted that the distribution of radio frequency energy within the second housing 120 can be directly obtained by monitoring equipment, or indirectly obtained by observing the actual coating or etching conditions exhibited by the chip 190. For example, taking the PVD process as an example, if there is uneven film thickness on the surface of the chip 190, it indicates that the memory in the second housing 120 has an uneven distribution of radio frequency energy; similarly, if there is uneven etching on the surface of the chip 190, it also indicates that the memory in the second housing 120 has an uneven distribution of radio frequency energy.

[0021] As can be seen from the above description, the upper electrode structure disclosed in this application improves the related technology. When there is a problem with the uniformity of radio frequency energy in the second housing 120, the capacitance of the local area between the first housing 110 and the second housing 120 can be adjusted by the capacitance adjustment device 130. Since the radio frequency energy in the second housing 120 is transferred to the first housing 110 and the outside through capacitive coupling, the amount of radio frequency energy transferred will also change in the area where the capacitance of the first housing 110 and the second housing 120 changes. Thus, the uniformity of radio frequency energy in the second housing 120 can be adjusted by controlling the amount of radio frequency energy transferred, thereby improving the uniformity of the coating process or etching process and ensuring the yield of the wafer 190 manufacturing process.

[0022] As shown in Figures 1 and 5, the first housing 110 may include a shield plate 111 and a shield cylinder 112. Both the shield plate 111 and the shield cylinder 112 are made of metal. The shield plate 111 is located on top of the shield cylinder 112 and is assembled with the shield cylinder 112 to form the internal space of the first housing 110. The second housing 120 includes a diffuser plate 121 and a conductive cylinder 122. Both the diffuser plate 121 and the conductive cylinder 122 are made of metal. The diffuser plate 121 is located on top of the conductive cylinder 122. The diffuser plate 121 and the conductive cylinder 122 together form the internal space of the second housing 120. The diffuser plate 121 is electrically connected to a radio frequency power supply, and the radio frequency power supply can transfer radio frequency energy into the second housing 120 through the diffuser plate 121. It should be noted that the top and bottom of the conductive cylinder 122 are the two ends of the conductive cylinder 122 along its own axial direction.

[0023] The first housing 110 is sleeved outside the second housing 120. The diffuser plate 121 and the shield plate 111 are opposite to each other and spaced apart, forming an approximately parallel plate capacitor device. The diffuser plate 121 can transfer radio frequency energy to the shield plate 111 by capacitive coupling. The shield cylinder 112 is sleeved outside the conductive cylinder 122, and the inner wall of the shield cylinder 112 and the outer wall of the conductive cylinder 122 are fitted with a gap, which can also form an approximately parallel plate capacitor device. The conductive cylinder 122 can transfer radio frequency energy to the shield cylinder 112 by capacitive coupling.

[0024] A capacitor adjustment device 130 can be provided between the diffuser plate 121 and the shield plate 111, or between the shield cylinder 112 and the conductive cylinder 122, or both of the above positions. It should be noted that the capacitor adjustment device 130 can be in contact with the diffuser plate 121 and the shield plate 111, or it can be spaced apart from each other; similarly, the capacitor adjustment device 130 can be in contact with the shield cylinder 112 and the conductive cylinder 122, or it can be spaced apart from each other. When adjusting the uniformity of radio frequency energy within the second housing 120, adjustment can be made by providing the capacitor adjustment device 130 between the diffuser plate 121 and the shield plate 111, or by providing the capacitor adjustment device 130 between the shield cylinder 112 and the conductive cylinder 122. Furthermore, the capacitor adjustment devices 130 at both positions can be adjusted simultaneously to further improve the uniformity of radio frequency energy.

[0025] In some embodiments of this application, as shown in Figures 1 to 4, the capacitor adjustment device 130 may include at least one first insulating plate 131. The first insulating plate 131 may be made of dielectric materials such as resin, quartz, or polytetrafluoroethylene. The first insulating plate 131 is disposed between the shielding plate 111 and the diffuser plate 121. The radio frequency power supply may be electrically connected to the diffuser plate 121 via the conductive post 140, so that the radio frequency energy may be fed into the second housing 120 via the conductive post 140 and the diffuser plate 121. The first insulating plate 131 may... The position of the first insulating plate 131 can be switched around the circumference of the conductive post 140 in a manner movably connected to the conductive post 140, thereby adjusting the capacitance of the local area where the first insulating plate 131 is located between the shielding plate 111 and the diffuser plate 121. Alternatively, the first insulating plate 131 can be set in different areas between the shielding plate 111 and the diffuser plate 121, and the number of first insulating plates 131 can be one, two, or more, depending on the capacitance adjustment requirements between the shielding plate 111 and the diffuser plate 121. This embodiment does not limit this. It should be noted that, along the vertical direction of the surface of the diffuser plate 121, the projected area of ​​the first insulating plate 131 can be smaller than the projected area of ​​the diffuser plate 121, thereby enabling fine adjustment in a smaller area.

[0026] Since the diffuser plate 121 can transfer radio frequency energy to the mask plate 111 via capacitive coupling, and the diffuser plate 121 and the mask plate 111 are arranged at intervals to form an approximately parallel plate capacitor, when the capacitance of each local area between the mask plate 111 and the diffuser plate 121 changes, the amount of radio frequency energy transferred will also change. In actual use, taking the coating process of the wafer 190 as an example, the wafer 190 is placed below the second housing 120. Along the vertical direction of the surface of the diffuser plate 121, the projected area of ​​the diffuser plate 121 can completely cover the wafer 190, and the diffuser plate 121 and the wafer 190 can also be arranged concentrically.

[0027] As shown in Figure 4, the shaded area is the wafer 190, the dashed area is the diffuser plate 121, and the fan-shaped area is the first insulating plate 131. The wafer 190 has a thicker film layer at the 9 o'clock position (the thicker area), so the first insulating plate 131 can also be installed at the 9 o'clock position. During the process of radio frequency energy entering the diffuser plate 121 from the conductive pillar 140 and being transmitted to the surroundings, a device similar to a parallel plate capacitor is formed between the mask plate 111 and the diffuser plate 121. The radio frequency energy in the second housing 120 can be transmitted to the first housing 110 and the outside through capacitive coupling.

[0028] When a first insulating plate 131 is added between the shielding plate 111 and the diffuser plate 121, the dielectric material between the two parallel plates changes from air to an insulating material (resin, quartz, polytetrafluoroethylene, etc.). Generally, the dielectric constant ε of insulating materials is greater than that of air. According to the capacitance formula of a parallel plate capacitor, C=(εS) / (4πkd), after adding the first insulating plate 131, the capacitance between the shielding plate 111 and the diffuser plate 121 increases, resulting in stronger conduction of radio frequency energy. Therefore, more radio frequency energy will be transferred from this position to the first housing 110 and the outside, reducing the radio frequency energy in the 9 o'clock direction inside the second housing 120. After the radio frequency energy is reduced, the film layer in the thicker area on the wafer 190 will become thinner, thereby adjusting the uniformity of the film layer thickness.

[0029] In Figure 4, the first insulating plate 131 is fan-shaped. It should be noted that the shape of the first insulating plate 131 can also be square, triangular, rhomboid, circular, elliptical, trapezoidal, or other irregular shapes. Specifically, the shape of the first insulating plate 131 can be selected according to the distribution of the film layers on the wafer 190. The thickness of the first insulating plate 131 can be selected based on the capacitance adjustment amount corresponding to the film layer thickness on the wafer 190. For example, if the thickness difference between the thicker and normal areas of the film layer is small, the required capacitance adjustment is also small, and the corresponding thickness of the first insulating plate 131 does not need to be too large. Conversely, if the thickness difference between the thicker and normal areas of the film layer is large, the required capacitance adjustment is also large, and the corresponding thickness of the first insulating plate 131 needs to be larger.

[0030] When installing the first insulating plate 131, it can be connected to the cover plate 111. For example, as shown in Figures 1 to 4, bolt holes can be made on both the first insulating plate 131 and the cover plate 111. Bolts are used to fix the first insulating plate 131 and the cover plate 111. There are a large number of bolt holes on the cover plate 111, and they need to cover the entire cover plate 111 as much as possible. When it is necessary to adjust the position of the first insulating plate 131, the first insulating plate 131 can be removed from the cover plate 111, and then re-fixed after changing its position. In addition, the first insulating plate 131 and the cover plate 111 can also be connected by a snap-fit, which is convenient for disassembly and can further improve the efficiency of the first insulating plate 131 when changing its position.

[0031] The first insulating plate 131 can also be connected to the diffuser plate 121. Bolt holes can be made on both the first insulating plate 131 and the diffuser plate 121, and bolts can be used to fix the first insulating plate 131 and the diffuser plate 121. There are a large number of bolt holes on the diffuser plate 121, and they need to cover the entire diffuser plate 121 as much as possible. When it is necessary to adjust the position of the first insulating plate 131, the first insulating plate 131 can be removed from the diffuser plate 121, and then re-fixed after changing its position. In addition, the first insulating plate 131 and the diffuser plate 121 can also be connected by a snap-fit, which is convenient for disassembly and can further improve the efficiency of the first insulating plate 131 when changing its position.

[0032] In some embodiments of this application, the first insulating plate 131 can also be installed by a rotatable connection. Specifically, the process chamber 100 is provided with a conductive post 140, which passes through the shielding plate 111. One end of the conductive post 140 is used to connect to the radio frequency power supply, and the other end of the conductive post 140 is electrically connected to the diffuser plate 121, thereby feeding radio frequency energy into the second housing 120 through the diffuser plate 121. Since the radio frequency energy diffuses around the conductive post 140, the first insulating plate 131 can be rotatably connected to the conductive post 140 based on the conductive post 140. Specifically, the rotatable connection can be achieved by a bearing or a flexible connector. During the rotation of the first insulating plate 131 relative to the conductive post 140, the capacitance of different areas around the conductive post 140 can be adjusted. Furthermore, the rotatable connection with the conductive post 140 makes it easier to adjust the position of the first insulating plate 131, improving the flexibility of use.

[0033] Regarding the aforementioned capacitor adjustment device 130, it can also be disposed between the conductive cylinder 122 and the shield cylinder 112. Specifically, as shown in Figures 5 to 14, the capacitor adjustment device 130 can further include at least one second insulating plate 132. The second insulating plate 132 can be made of dielectric materials such as resin, quartz, or polytetrafluoroethylene. The second insulating plate 132 is movably disposed between the shield cylinder 112 and the conductive cylinder 122. The radio frequency power supply is electrically connected to the diffuser plate 121 via the conductive post 140. The radio frequency energy can be fed into the second housing 120 via the conductive post 140 and the diffuser plate 121 and diffused along the axial direction of the conductive cylinder 122. The second insulating plate 132 can switch positions along the circumference of the conductive cylinder 122 in a manner movably connected to the shield cylinder 112, thereby adjusting the capacitance of the local area where the second insulating plate 132 is located between the shield cylinder 112 and the conductive cylinder 122. In addition, along the radial direction of the conductive cylinder 122, the projected area of ​​the second insulating plate 132 can be smaller than the projected area of ​​the conductive cylinder 122, thereby enabling fine adjustment in a smaller area. The second insulating plate 132 can be a flat plate or an arc-shaped plate.

[0034] Since the conductive cylinder 122 can transfer radio frequency energy to the shield cylinder 112 via capacitive coupling, an approximately parallel plate capacitor is formed between the outer wall of the conductive cylinder 122 and the inner wall of the shield cylinder 112. When the capacitance of the local area where the second insulating plate 132 is located between the shield cylinder 112 and the conductive cylinder 122 changes, the amount of radio frequency energy loss will also change. In actual use, taking the processing of the wafer 190 as an example, the wafer 190 is placed below the second housing 120. When the film layer on the wafer 190 has a local thickness problem, it indicates that the radio frequency energy above the thicker area is greater. The second insulating plate 132 can be moved between the shield cylinder 112 and the conductive cylinder 122 and closer to the area with greater radio frequency energy, so that the area with greater radio frequency energy can transfer more energy to the shield cylinder 112 and the outside via capacitive coupling, thereby reducing the radio frequency energy in that area.

[0035] The second insulating plate 132 can be detachably connected to the inner wall of the shielding cylinder 112 or to the outer wall of the conductive cylinder 122. When the position of the second insulating plate 132 needs to be adjusted, the second insulating plate 132 can be removed from the inner wall of the shielding cylinder 112 or the outer wall of the conductive cylinder 122, and reassembled after switching positions. The number of second insulating plates 132 can be one, two, or more, depending on the capacitance adjustment requirements between the shielding cylinder 112 and the conductive cylinder 122. This embodiment does not limit this.

[0036] In some embodiments of this application, as shown in Figures 5 to 10, the capacitance adjustment device 130 may further include a mounting bracket 133 and a driving mechanism 134. The mounting bracket 133 is connected to the inner wall of the shielding cylinder 112 and extends circumferentially along the shielding cylinder 112. The specific connection method can be bonding, bolting, snap-fitting, etc. The driving mechanism 134 is connected to the second insulating plate 132. The driving mechanism 134 and the mounting bracket 133 can move relative to each other, thereby driving the second insulating plate 132 to move circumferentially along the shielding cylinder 112 to adjust the capacitance of each local area between the shielding cylinder 112 and the conductive cylinder 122. The driving mechanism 134 and the mounting bracket 133 can be slidably connected or rolled. The ends of the driving mechanism 134 and the second insulating plate 132 can be assembled by bonding, bolting, snap-fitting, etc.

[0037] As shown in Figures 6 to 10, the mounting bracket 133 may specifically include a first bracket 1331 and a second bracket 1332. The first bracket 1331 is connected to the inner wall of the shielding cylinder 112, such as by bonding, bolting, or snapping. The first bracket 1331 and the inner wall of the shielding cylinder 112 can serve as the mounting base for the second bracket 1332. The second bracket 1332 is fixed by the first bracket 1331 and the inner wall of the shielding cylinder 112. Since the drive mechanism 134 needs to move the second insulating plate 132 circumferentially along the shielding cylinder 112, to avoid interference between the second bracket 1332, the drive mechanism 134, and the second insulating plate 132, a clearance hole 1333 can be provided on the second bracket 1332. The clearance hole 1333 extends circumferentially along the shielding cylinder 112. The drive mechanism 134 overlaps the second bracket 1332 and moves along the clearance hole 1333 to move the second insulating plate 132 along the clearance hole 1333. When moving along the clearance hole 1333, the drive mechanism 134 or the second insulating plate 132 can partially extend into the clearance hole 1333.

[0038] As shown in Figures 5, 6, 11, and 12, the aforementioned drive mechanism 134 may specifically include a drive component 1341, a base 1342, and a traveling wheel 1343. The drive component 1341 may be a motor, a cylinder, etc. The drive component 1341 is disposed on the base 1342. The traveling wheel 1343 is disposed on the side of the base 1342 and is rotatably connected to the base 1342. The traveling wheel 1343 rests on the second bracket 1332 and can move relative to the second bracket 1332 by rolling. The number of traveling wheels 1343 may be two or more. The two or more traveling wheels 1343 may be disposed on two opposite sides of the base 1342 to support the base 1342 and rest on the second bracket 1332 respectively. The second insulating plate 132 is connected to the side of the base 1342 facing away from the drive member 1341. The drive member 1341 and the traveling wheel 1343 can be driven by a transmission mechanism such as gears or belts. The drive member 1341 can drive the traveling wheel 1343 to rotate, so that the base 1342 can move along the clearance hole 1333 via the traveling wheel 1343, thereby driving the second insulating plate 132 to move circumferentially along the shielding cylinder 112, so as to flexibly adjust the capacitance of each local area between the shielding cylinder 112 and the conductive cylinder 122. It should be added that the drive member 1341 can be electrically driven. In order to facilitate the laying of power cables, wiring holes or wiring grooves can be provided on the first bracket 1331 to accommodate power cables.

[0039] As shown in Figure 6, in order to improve the stability of the second insulating plate 132 when it moves, a traveling wheel 1343 can be provided on both sides of the base 1342 along the radial direction of the shield cylinder 112, and a track groove 1334 can be provided on both sides of the second bracket 1332 along the radial direction of the shield cylinder 112. The traveling wheel 1343 extends into the track groove 1334 and is guided and cooperates with the track groove 1334, thereby improving the stability of the base 1342 when it runs, and thus improving the stability of the second insulating plate 132 when it moves.

[0040] In some embodiments of this application, in the examples shown in Figures 5 to 14, the capacitance adjustment device 130 includes two second insulating plates 132 and two driving mechanisms 134. It is understood that the capacitance adjustment device 130 may include n second insulating plates 132 and n driving mechanisms 134. The second support 1332 includes n+1 sub-supports 1332a. The outermost sub-support 1332a is connected to the inner wall of the shield cylinder 112, and the remaining sub-supports 1332a are respectively connected to the first support 1331. The n+1 sub-supports 1332a are located on the same side of the first support 1331 and are spaced apart from each other to form n clearance holes 1333. The clearance holes 1333 are formed between adjacent sub-supports 1332a. It should be noted that n≥2, and the outermost sub-support 1332a is the sub-support 1332a closest to the shield cylinder 112 among the n+1 sub-supports 1332a. The drive mechanism 134 is attached to two adjacent sub-supports 1332a. The drive mechanism 134 can move along the clearance hole 1333, thereby driving the second insulating plate 132 to move along the clearance hole 1333.

[0041] By employing the design of at least two second insulating plates 132 described above, the capacitance adjustment range between the conductive cylinder 122 and the shielding cylinder 112 can be expanded. Specifically, as shown in FIG13, two second insulating plates 132 are provided on the mounting bracket 133, and two thicker regions appear on the wafer 190. The circular dotted line between the wafer 190 and the mounting bracket 133 represents the conductive cylinder 122. The driving mechanism 134 can be used to move the two second insulating plates 132 to designated positions respectively. The positions of the two second insulating plates 132 correspond to the thicker regions of the film layer on the wafer 190. The two insulating plates can be moved to two different positions on the corresponding wafer 190, thereby increasing the viewing window for thickness uniformity adjustment.

[0042] As radio frequency energy enters the diffuser plate 121 from the conductive post 140 and is transferred to the target material 160 via the conductive cylinder 122, a parallel-plate capacitor-like device is formed between the conductive cylinder 122 and the shield cylinder 112, and the radio frequency energy is transferred through capacitive coupling. When a second insulating plate 132 is added between the conductive cylinder 122 and the shield cylinder 112, the dielectric material between the two parallel plates changes from air to an insulating material (resin, quartz, polytetrafluoroethylene, etc.). Generally, the dielectric constant ε of insulating materials is greater than that of air. According to the capacitance formula of a parallel-plate capacitor, C=(εS) / (4πkd), after adding the second insulating plate 132, the capacitance between the conductive cylinder 122 and the shield cylinder 112 increases, and the radio frequency energy conduction capability is enhanced. Therefore, more radio frequency energy will be transferred from this position to the shield cylinder 112 and the outside, thereby reducing the radio frequency energy in the area where the second housing 120 is located by the second insulating plate 132. When the radio frequency energy is reduced, the film thickness at the corresponding location on the wafer 190 will become thinner, thereby adjusting the uniformity of the film thickness.

[0043] During use, the two second insulating plates 132 can also be moved to the position shown in Figure 14, so that the two second insulating plates 132 overlap, which will further increase the capacitance, thus making the radio frequency energy transfer efficiency greater and the thickness reduction effect more obvious. In some application scenarios, the first insulating plate 131 and the second insulating plate 132 can be used in combination to improve the adjustment range and adaptation range of the capacitance.

[0044] The size of the second insulating plate 132 has a significant impact on the capacitance. Along the circumference of the conductive cylinder 122, the length ratio of the second insulating plate 132 to the conductive cylinder 122 can be 1:8 to 1:4; along the axial direction of the conductive cylinder 122, the length ratio can be 1:3 to 1:1. Regarding the size of the second insulating plate 132, using a smaller size is beneficial for achieving finer capacitance adjustment, while using a larger size is beneficial for improving capacitance adjustment capability. The larger the size of the second insulating plate 132, the greater the capacitance change between the shielding cylinder 112 and the conductive cylinder 122, and the stronger the ability to adjust RF energy loss. In practical applications, the specific size of the second insulating plate 132 can be selected based on the distribution of the film layers on the wafer 190.

[0045] Referring to Figures 1 to 14, this application also discloses a semiconductor process apparatus. The disclosed semiconductor process apparatus includes a radio frequency (RF) power supply, a reaction chamber 200, and the aforementioned upper electrode structure. The RF power supply is electrically connected to the upper electrode structure, and the reaction chamber 200 is located below the upper electrode structure. The RF power supply feeds RF energy into the reaction chamber 200 through the upper electrode structure to excite the process gas in the reaction chamber 200 to a plasma state.

[0046] As can be seen from the above description, the upper electrode structure disclosed in this application improves the related technology. When there is a problem with the uniformity of radio frequency energy in the second housing 120, the capacitance of the local area between the first housing 110 and the second housing 120 can be adjusted by the capacitance adjustment device 130. Since the radio frequency energy in the second housing 120 is transferred to the first housing 110 through capacitive coupling, the amount of radio frequency energy transferred will also change in the area where the capacitance of the first housing 110 and the second housing 120 changes. Thus, the uniformity of radio frequency energy in the second housing 120 can be adjusted by controlling the amount of radio frequency energy transferred, thereby improving the uniformity of the coating process or etching process and ensuring the yield of the wafer 190 manufacturing process.

[0047] Further, the aforementioned semiconductor process equipment may include a physical vapor deposition (PVD) apparatus, which can perform PVD processes. The PVD apparatus may include a magnetron assembly 150 and a target 160. At least a portion of the magnetron assembly 150 is disposed within the second housing 120, and the target 160 is disposed at the bottom of the second housing 120. A liner 170 is also disposed below the second housing 120, and a base 180 is disposed at the bottom of the liner 170. The base 180 has a bearing surface for supporting the wafer 190. Radio frequency power is fed into the diffuser plate 121 via conductive pillars 140, and then into the target 160 via conductive cylinders 122. The magnetron assembly 150 can rotate at a constant speed via a rotating shaft, so that the magnetic field distributed on the surface of the target 160 can confine free electrons, thereby making it easier to maintain a uniform distribution of plasma within the reaction chamber 200.

[0048] The above embodiments of this application focus on describing the differences between the various embodiments. As long as the different technical features between the various embodiments are not contradictory, they can be combined to form more specific embodiments. Considering the brevity of the text, they will not be described in detail here.

[0049] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of protection of this application. All of these forms are within the protection scope of this application. [Simplified Explanation of the Diagram]

[0007] Figure 1 is a schematic diagram of the structure of the semiconductor process equipment disclosed in the embodiment of this application; Figure 2 is a schematic diagram of the relative positions of the first insulating plate and the diffusion plate disclosed in the embodiment of this application; Figure 3 is a schematic diagram of the structure of the first insulating plate disclosed in the embodiment of this application; Figure 4 is a schematic diagram of the relative positions of the first insulating plate, the wafer, and the diffusion plate disclosed in the embodiment of this application; Figure 5 is a schematic diagram of the upper electrode structure disclosed in the embodiment of this application; Figure 6 is a schematic diagram of the structure of the mounting bracket, the driving mechanism, and the second insulating plate disclosed in the embodiment of this application; Figure 7 is a top view of the first bracket disclosed in the embodiment of this application; Figure 8 is one of the top views of the sub-bracket disclosed in the embodiment of this application; Figure 9 is another top view of the sub-bracket disclosed in the embodiment of this application; Figure 10 is a third top view of the sub-bracket disclosed in the embodiment of this application; Figure 11 is one of the schematic diagrams of the structure of the driving mechanism and the second insulating plate disclosed in the embodiment of this application; Figure 12 is another schematic diagram of the structure of the driving mechanism and the second insulating plate disclosed in the embodiment of this application; Figure 13 is one of the schematic diagrams of the relative positions of the second insulating plate, the conductive cylinder, and the wafer disclosed in the embodiment of this application; Figure 14 is a second schematic diagram showing the relative positions of the second insulating plate, conductive cylinder, and wafer disclosed in the embodiments of this application.

Claims

1. An upper electrode structure for a physical vapor deposition apparatus, the upper electrode structure comprising a first housing, a second housing, and a capacitance adjustment device; the second housing is disposed within the first housing, a plurality of components are asymmetrically arranged within the second housing, and a gap exists between the first housing and the second housing, the capacitance adjustment device being disposed in the gap for adjusting the capacitance of a local area between the first housing and the second housing.

2. The upper electrode structure as described in claim 1, wherein, The first housing includes a shield plate and a shield cylinder, the shield plate being disposed on top of the shield cylinder. The second housing includes a diffuser plate for transmitting radio frequency energy and a conductive cylinder, the diffuser plate being disposed on top of the conductive cylinder. The diffuser plate is disposed opposite to the shield plate, and the conductive cylinder is disposed inside the shield cylinder. At least one of the space between the diffuser plate and the shield plate and the space between the shield cylinder and the conductive cylinder is provided with the capacitance adjustment device.

3. The upper electrode structure as described in claim 2, wherein, The capacitance adjustment device includes at least one first insulating plate disposed between the shielding plate and the diffuser plate, for adjusting the capacitance of the local area where the first insulating plate is located between the shielding plate and the diffuser plate.

4. The upper electrode structure as described in claim 3, wherein, The first insulating plate is connected to the shielding plate.

5. The upper electrode structure as described in claim 2, wherein, The capacitance adjustment device includes at least one second insulating plate, which is movably disposed between the shielding cylinder and the conductive cylinder, for adjusting the capacitance of the local area where the second insulating plate is located between the shielding cylinder and the conductive cylinder.

6. The upper electrode structure as described in claim 5, wherein, The capacitor adjustment device also includes a mounting bracket and a drive mechanism. The mounting bracket is connected to the inner wall of the shield cylinder and extends circumferentially along the shield cylinder. The drive mechanism is connected to the second insulating plate and can move relative to the mounting bracket to drive the second insulating plate to move circumferentially along the shield cylinder.

7. The upper electrode structure as described in claim 6, wherein, The mounting bracket includes a first bracket and a second bracket. The first bracket is connected to the inner wall of the shield cylinder, and the second bracket is fixed to the inner wall of the shield cylinder by means of the first bracket. The second bracket is provided with a clearance hole that extends along the circumference of the shield cylinder. The drive mechanism is attached to the second bracket and moves along the clearance hole to drive the second insulating plate to move along the clearance hole.

8. The upper electrode structure as described in claim 7, wherein, The drive mechanism includes a drive component, a base, and a traveling wheel. The drive component is disposed on the base, and the traveling wheel is rotatably connected to the base. The second insulating plate is connected to the side of the base facing away from the drive component. The drive component is used to drive the traveling wheel to rotate so that the base moves along the clearance hole by means of the traveling wheel.

9. The upper electrode structure as described in claim 8, wherein, The base is provided with the traveling wheels on both sides of the radial direction of the shield cylinder, and the second bracket is provided with the track grooves on both sides of the radial direction of the shield cylinder. The traveling wheels extend into the track grooves and are guided and engaged with the track grooves.

10. The upper electrode structure as described in claim 9, wherein, The capacitor adjustment device includes n second insulating plates and n driving mechanisms. The second support includes n+1 sub-supports. The outermost sub-support is connected to the shielding cylinder, and the remaining sub-supports are connected to the first support. The n+1 sub-supports are located on the same side of the first support and are spaced apart from each other to form n clearance holes, where n≥2. The driving mechanism is attached to two adjacent sub-supports and moves along the clearance holes to drive the second insulating plate to move along the clearance holes.

11. The upper electrode structure as described in claim 5, wherein, Along the circumference of the conductive cylinder, the length ratio of the second insulating plate to the conductive cylinder is 1:8 to 1:4; along the axial direction of the conductive cylinder, the length ratio of the second insulating plate to the conductive cylinder is 1:3 to 1:

1.

12. A semiconductor manufacturing apparatus comprising a radio frequency power supply, a reaction chamber, and an upper electrode structure as described in any one of claims 1 to 11; the radio frequency power supply being electrically connected to the upper electrode structure, and the reaction chamber being disposed below the upper electrode structure.

13. The semiconductor manufacturing apparatus as claimed in claim 12, wherein, The semiconductor manufacturing equipment includes a physical vapor deposition apparatus, which includes a magnetron assembly and a target. At least a portion of the magnetron assembly is disposed within the second housing, and the target is disposed at the bottom of the second housing.

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