Multi-radius magnetron for physical vapor deposition (PVD) and methods of use thereof

Abstract

This document provides methods and apparatus for processing substrates. In an embodiment, a magnetron assembly for use in a PVD chamber includes: a base plate having a first side, a second side opposite to the first side, and a central axis; a magnet plate rotatably coupled to the base plate, wherein the magnet plate rotates relative to the base plate about an offset axis; a magnet assembly coupled to the magnet plate offset from the offset axis and configured to rotate about the central axis and the offset axis; a first motor coupled to the base plate to rotate the magnet assembly about the central axis; and a second motor coupled to the magnet plate to control its angular position and position the magnet assembly at each of a plurality of fixed angular positions defining a plurality of different fixed radii.

Description

Technical Field

[0001] The embodiments of this disclosure pertain to a large system of substrate processing equipment. Prior Technology

[0002] Semiconductor devices are generally fabricated as integrated circuits on a substrate, with various conductive layers interconnected to facilitate signal propagation within the device. In some cases, devices are interconnected vias or electrical connections, which are provided by different layers of the integrated circuit. Through-silicon vias (TSVs) formed in silicon are called TSVs. As circuit complexity increases, the size of semiconductor structures decreases, allowing for more structures within a given area. More and more layers are incorporated to increase the density of the integrated circuit. High density forces TSV diameters to decrease, while the increased number of layers requires a significant increase in TSV depth. The inventors have discovered that due to the small diameter and increased depth of TSVs, barrier layer materials such as copper or tantalum, for example, cannot be uniformly sputtered onto the sides and bottom of the TSVs in a physical vapor deposition (PVD) chamber.

[0003] Therefore, the inventors have provided an improved PVD chamber for uniformly depositing material on high aspect ratio TSV structures. Summary of the Invention

[0004] This document provides a method and apparatus for processing a substrate in a PVD chamber. In some embodiments, a magnetron assembly for a PVD chamber includes: a base plate having a first side, a second side opposite to the first side, and a central axis; a magnet plate rotatably coupled to the base plate on the first side of the base plate, wherein the magnet plate rotates relative to the base plate about an offset axis; a magnet assembly coupled to the magnet plate offset from the offset axis and configured to rotate about the central axis and the offset axis; a first motor coupled to the base plate to rotate the magnet assembly about the central axis; and a second motor coupled to the magnet plate to control its angular position and position the magnet assembly at each of a plurality of fixed angular positions defining a plurality of different fixed radii, wherein the magnet assembly is configured to rotate 360 ​​degrees about the central axis at each of the plurality of fixed radii.

[0005] In some embodiments, the method of depositing a metal film on a substrate includes: positioning a magnet assembly at a first fixed radius relative to the central axis of a target in a physical vapor deposition (PVD) chamber; depositing a metal film onto a substrate disposed opposite to the target in the PVD chamber while rotating the magnet assembly at the first fixed radius relative to the central axis for a first time period; positioning the magnet assembly at a second fixed radius relative to the central axis by rotating the magnet assembly about an offset axis; and depositing a metal film onto the substrate while rotating the magnet assembly at the second fixed radius relative to the central axis for a second time period.

[0006] In some embodiments, a non-transitory computer-readable medium for storing computer instructions, when executed by at least one processor, causes the at least one processor to perform a method comprising: positioning a magnet assembly at a first fixed radius relative to a central axis of a target in a physical vapor deposition (PVD) chamber; depositing a metal film onto a substrate disposed opposite to the target in the PVD chamber while rotating the magnet assembly relative to the central axis by the first fixed radius for a first time period; positioning the magnet assembly at a second fixed radius relative to the central axis by rotating the magnet assembly about an offset axis; and depositing a metal film onto the substrate while rotating the magnet assembly relative to the central axis by the second fixed radius for a second time period.

[0007] Other and further embodiments of this disclosure are described below. Simple Explanation of the Diagram

[0008] The embodiments of this disclosure, which have been briefly described above and discussed in more detail below, can be understood by referring to the illustrative embodiments depicted in the accompanying drawings. However, the drawings only show typical embodiments of this disclosure and should not be considered as limiting the scope, as other equally effective embodiments are permissible.

[0009] Figure 1 depicts a schematic side view of a PVD chamber according to some embodiments of this disclosure.

[0010] Figure 2 depicts a schematic cross-sectional view of a magnetron assembly according to some embodiments of this disclosure.

[0011] Figure 3A depicts a schematic bottom view of a magnetron assembly according to some embodiments of this disclosure.

[0012] Figure 3B depicts a schematic bottom view of a magnetron assembly according to some embodiments of this disclosure.

[0013] Figure 3C depicts a schematic bottom view of a magnetron assembly according to some embodiments of this disclosure.

[0014] Figure 4 depicts a schematic cross-sectional view of a magnetron assembly according to some embodiments of this disclosure.

[0015] Figure 5 depicts a flowchart of a method for depositing a metal film onto a substrate in a PVD chamber according to some embodiments of this disclosure.

[0016] For ease of understanding, the same component symbols are used as much as possible to represent the same components in the drawings. The drawings are not drawn to scale and have been simplified for clarity. Components and features of one embodiment can be advantageously incorporated into other embodiments without further description. Implementation

[0017] This paper provides a method and apparatus for forming a barrier layer with increased step coverage in through silicon vias (TSVs) with high aspect ratio structures. The apparatus includes a physical vapor deposition (PVD) chamber comprising a magnetron assembly having a smaller and stronger magnet assembly with additional electromagnet control to enhance PVD copper coverage on the TSV structure while improving film uniformity. The magnet assembly used with the method provided herein produces a high ionization fraction, which advantageously results in better step coverage performance. Process formulations using magnet assemblies located at multiple radii from the central axis of the magnetron assembly advantageously improve step coverage and film deposition rate. For example, the process formulation may include a five-radius process formulation. The PVD chamber may also include lower and upper electromagnets surrounding the chamber body. The additional upper electromagnet helps to direct ions that would normally be lost on the chamber shield to the substrate, resulting in more ions and better control of the non-uniformity percentage (NU%) on the substrate.

[0018] As the extension of classical Mohr's Law slows, the semiconductor industry is seeking new vertical scaling paradigms to drive improvements in power, performance, and cost. TSVs are indispensable enablers for 3D packaging. Expanding TSV aspect ratios from 5x50 μm to 3x50 μm presents challenges to PVD coverage and the ability to achieve continuous barrier and seed layers on TSVs. Smaller diameters and higher aspect ratios necessitate thicker PVD films, increasing costs and allowing competition from alternative non-PVD metallization methods. The PVD chamber principle of this invention enables cost-effective TSV metallization for next-generation TSVs and enables greater market adoption of 3D packaging.

[0019] In some embodiments, the PVD chamber includes enhanced grounding for RF bias current return to achieve more uniform deposition, a deposition ring with enhanced deposition control, and / or a magnetron assembly with a magnet assembly for increasing deposition rate and coverage. In some embodiments, the PVD chamber includes higher DC power to improve coverage and deposition rate, higher RF bias to maintain constant high ion energy, and / or a source element with a central water supply magnetron assembly to enable a stable deposition rate during target etching.

[0020] Figure 1 is a cross-sectional view of a PVD chamber 100 according to some embodiments. The PVD chamber 100 can be used to deposit copper and other materials onto a substrate 110, which may include semiconductor structures such as TSVs. In some embodiments, the PVD chamber 100 can provide a deposition rate of about 80 Å / s to about 135 Å / s or greater using a DC power of about 30 kW to about 50 kW and an RF bias power of about 1.6 kW to 2.8 kW, while achieving a film resistivity percentage (Rs) of less than about 5% NU%. The PVD chamber 100 includes a chamber body 102 and a source 190. The chamber body 102 includes a processing volume 118 disposed therein, and the source 190 includes a magnetron assembly 104 and a target 112. The substrate 110 is supported on a substrate support assembly 192, which includes an electrostatic chuck (ESC) 108 supported by a substrate support base 106. One or more gases may be supplied from gas source 184 to the lower part of PVD chamber 100. Pump 182 is connected to PVD chamber 100 to evacuate the interior of PVD chamber 100 and helps maintain the desired pressure inside PVD chamber 100.

[0021] At the top of the processing volume 118 is a target 112 with a backplate 114. The target 112 includes a sputtering surface 156 facing the substrate 110. In some embodiments, the target 112 may be made of copper, titanium, tantalum, tungsten, etc. A DC power supply 128 provides DC power to the target 112 via the backplate 114 to sputter the target 112 during processing. The backplate 114 may include a conductive material, such as copper-zinc, copper-chromium, or the same material as the target 112, such that DC power can be coupled to the target 112 via the backplate 114. Alternatively, the backplate 114 may be non-conductive and may include conductive elements (not shown), such as electrical feedthroughs, etc. The backplate 114 may be disc-shaped, rectangular, square, or any other shape that can be accommodated by the PVD chamber 100. The backplate 114 is configured to support the target 112 such that the front surface of the target 112 is opposite to the substrate 110 in presence. The target 112 may be coupled to the backplate 114 in any suitable manner. For example, in some embodiments, the target 112 may be diffusely bonded to the backplate 114.

[0022] The magnetron assembly 104 includes a magnet assembly 136 that travels on a target 112 at a plurality of different fixed radii or fixed positions about a central axis 154. In some embodiments, the magnet assembly 136 may include a plurality of individual magnets. A support device 134 supports the magnet assembly 136 and enables the magnet assembly 136 to rotate about the central axis 154. In some embodiments, a first motor 174 is coupled to the support device 134 to rotate the magnet assembly 136 about the central axis 154. The magnet assembly 136 may rotate about an offset axis 172 that is offset from the magnet assembly 136 and from the central axis 154 to position the magnet assembly 136 at each of the plurality of different fixed radii. In some embodiments, a second motor 178 is coupled to the magnet assembly 136 to rotate the magnet assembly 136 about the offset axis 172, thereby controlling the radial position of the magnet assembly 136 relative to the central axis 154. In some embodiments, the magnet assembly 136 is configured to rotate at least 180 degrees about the offset axis 172. In some embodiments, the magnet assembly 136 is configured to rotate approximately 180 degrees from a zero-degree position about an offset axis 172 to position the magnet assembly 136 at each of a plurality of different fixed radii. The zero-degree position may correspond to the magnet assembly 136 being at its innermost radial position or its innermost radial radius. In some embodiments, the second motor 178 is configured to rotate the magnet assembly 136 independently of the first motor 174.

[0023] In some embodiments, unlike a typical magnetron assembly configured to rotate the magnet assembly in planetary motion (where the radius or distance between the magnet assembly and the central axis changes continuously), the magnetron assembly 104 is configured to position the magnet assembly 136 relative to the central axis at a fixed radius (e.g., a first fixed radius), and then rotate the magnet assembly 136 about the central axis 154 at a fixed radius for a predetermined time period (e.g., a first time period). The magnet assembly 136 is then positioned at a different fixed radius (e.g., a second fixed radius), and then rotates about the central axis 154 at a different fixed radius for subsequent time periods (e.g., a second time period). The magnet assembly 136 is repositioned to set different fixed radii, and the rotation of the magnet assembly 136 at different fixed radii in subsequent time periods can be repeated (e.g., to provide a third fixed radius, a fourth fixed radius, a fifth fixed radius, etc., as appropriate), as disclosed herein.

[0024] In some embodiments, the magnet assembly 136 is configured to rotate about a central axis 154 of the base plate 202 at five different radii, and the magnet plate 204 is configured to rotate about an offset axis 172 to position the magnet assembly 136 at each of the five different radii. In some embodiments, a first fixed radius may be referred to as the innermost radial radius (e.g., the minimum possible radius), and a fifth fixed radius may be referred to as the outermost radius (e.g., the maximum possible radius). In some embodiments, the first fixed radius is about 1.5 inches to about 2.6 inches. In some embodiments, the second fixed radius is about 2.6 inches to about 3.5 inches. In some embodiments, the third fixed radius is about 3.5 inches to about 4.5 inches. In some embodiments, the fourth fixed radius is about 4.5 inches to about 5.5 inches. In some embodiments, the fifth fixed radius is about 5.9 inches to about 7.5 inches.

[0025] In some embodiments, the source 190 of the PVD chamber 100 uses a central coolant supply 132 to maximize target lifetime by mitigating target cracking and / or bending due to overheating and reducing the deposition rate during target lifetime. In some embodiments, a conventionally supplied coolant structure supplies coolant from one side of the cavity 194 of the magnetron assembly 104. However, because the coolant flowing to the portion of target 112 directly below the magnet assembly 136 is blocked by the magnet assembly 136, the portion of target 112 directly below the magnet assembly 136 does not receive a sufficient amount of coolant. Consequently, as the magnetron assembly 104 rotates, the area through which the magnet assembly 136 moves becomes overheated, sometimes reaching 400°C. This creates a temperature gradient between the adequately cooled and inadequately cooled portions of the target 112. This temperature gradient leads to target cracking and / or bending.

[0026] To maintain the target 112 at a temperature below approximately 200°C, a coolant supply 132 is provided, which supplies coolant to the center of the target 112 (i.e., along the central axis 154). The central coolant supply 132 extends along the central axis 154 through the body portion 130. The coolant supply 132 includes a central channel 158 extending from a manifold portion 160 through the body portion 130 along the central axis 154. A coolant supply 166 is fluidly connected to the inlet 168 of the manifold portion 160 to supply coolant through the central coolant supply 132 and into the cavity 194. The central coolant supply 132 extends along the central axis 154 through the body portion 130 to supply coolant to the cavity 194 at the center of the target 112 (as shown by streamline 170). Thus, a more uniform coolant flow is advantageously achieved, thereby substantially reducing or eliminating the temperature gradient throughout the target 112 and reducing target breakage and bending. After passing through coolant supply 132 into cavity 194, the coolant then flows out of cavity 194 via an opening (not shown) formed in an outlet (not shown) located at the top of the cavity. A return line (not shown) is connected to the outlet to receive coolant after it has flowed through cavity 194.

[0027] The radio frequency (RF) bias power supply 126 may be coupled to the substrate support assembly 192 to sense a negative DC bias on the substrate 110. Furthermore, in some embodiments, a negative DC self-bias may be formed on the substrate 110 during processing. For example, the RF energy provided by the RF bias power supply 126 may be in a frequency range from about 2 MHz to about 60 MHz; for example, non-limiting frequencies such as 2 MHz, 2.2 MHz, 13.56 MHz, or 60 MHz may be used. In some embodiments, RF power may be provided in a range from about 1.9 kW to about 3.0 kW. In some embodiments, the provided RF power may vary based on the distance or radius of the magnet assembly 136 positioned relative to the central axis 154. For example, at the outermost radius, the provided RF bias power may be greater than at the innermost radial radius. In some embodiments, when the magnet assembly 136 is at a first fixed radius and a second fixed radius, the provided RF bias power may be about 2.0 MHz. In some embodiments, when the magnet assembly 136 is at the third fixed radius, the fourth fixed radius, and the fifth fixed radius, the supplied radio frequency bias power may be approximately 2.2 MHz.

[0028] In some embodiments, DC power can be supplied from DC power supply 128 to target 112 in the range of about 30 kW to about 50 kW. In some embodiments, DC power supply 128 can provide DC power in the range of about 36 kW to about 40 kW. In other applications, substrate support assembly 192 may be grounded or kept electrically floating.

[0029] The PVD chamber 100 further includes a processing kit shield or shield 152 to surround the processing volume 118 of the PVD chamber 100 and protect other chamber components from damage and / or contamination from the processing. In some embodiments, the shield 152 may be grounded to the chamber body at the uppermost point 196 to provide an RF ground return path. The shield 152 extends downward and may include a generally tubular portion having a generally constant diameter and generally surrounding the processing volume 118. The shield 152 extends downward along the wall of the chamber body 102 below the uppermost surface 198 of the ESC 108 and returns upward until it reaches the cover ring 122 (e.g., forming a U-shaped portion at the bottom of the shield 152). When the substrate support assembly 192 is in a lower loading position, the cover ring 122 rests on top of the upwardly extending interior of the shield 152. However, when the substrate support assembly 192 is in an upper deposition position, the cover ring 122 rests on the outer periphery of the deposition ring 120 to protect the substrate support assembly 192 from sputter deposition. The deposition ring 120 can be used to protect the edges of the substrate support assembly 192, including the substrate support base and / or ESC 108, from deposition around the edges of the substrate 110. In some embodiments, the deposition ring 120 has a large deposition cavity 186, which allows for more deposition buildup before the deposition ring 120 needs to be replaced.

[0030] In some embodiments, the lower magnet assembly 142 may be disposed around the PVD chamber 100 to selectively provide a magnetic field between the ESC 108 and the target 112. For example, when the substrate support assembly 192 is in the processing position, the lower magnet assembly 142 may be disposed in the region surrounding the exterior of the chamber body 102 directly above the ESC 108. In some embodiments, the upper magnet assembly 140 may be disposed around and outside the chamber body 102, closer to the target 112 than the ESC 108 (above the lower magnet assembly 142 when it is present). The lower magnet assembly 142 and / or the upper magnet assembly 140 may be electromagnets and may be coupled to a power source (not shown) for controlling the magnitude of the magnetic field generated by the electromagnets. The electromagnet generates a magnetic field B, which allows control of the direction and energy of the ions. Adding the upper magnet assembly 140 allows for control of the ion direction and energy with greater precision than using the lower magnet assembly 142 alone. This greater precision allows for improved step coverage of the TSV structure (deposition within the TSV).

[0031] The lower magnet assembly 142 and / or the upper magnet assembly 140 may be coupled to a coolant source (not shown) for controlling the temperature generated by the operation of the electromagnets. In some embodiments, a current of about 6.0 amps to about 16.0 amps is supplied to the upper magnet assembly 140. In some embodiments, a current of about -18.0 amps to about 18.0 amps is supplied to the lower magnet assembly 142 for the bottom inner magnet 142C. In some embodiments, a current of about -18.0 amps to about 18.0 amps is supplied to the lower magnet assembly 142 for the top inner magnet 142A and the top outer magnet 142B. In some embodiments, the bottom outer magnet 142D is not used.

[0032] Substrate processing systems using radio frequency (RF) generated plasma require a return path for the RF current generated during processing back to its source, such as the RF power supply that supplies the current. In some cases, the return path may include the current traveling along the base plate of the processing system through the substrate support (e.g., ESC) and then ultimately back to the source along the walls and / or shield of the processing system. When operating under certain processing conditions, inappropriate arcing can occur between chamber components, such as arcing between the substrate support assembly 192 (including ESC 108 and / or substrate support base 106) and adjacent chamber components, and / or stray plasma, resulting in component damage and / or particle generation that can further inappropriately contaminate the substrate disposed within the chamber. Within the processing volume 118, the processing kit and shield 152 are grounded to the chamber body 102 and provide the primary return of the plasma current. In some embodiments, the PVD chamber 100 may include one or more grounding rings 124 that electrically connect the substrate support assembly 192 (e.g., ESC 108 and / or substrate support base 106) to the shield 152.

[0033] Controller 144 may be provided and coupled to various components of PVD chamber 100 to control its operation. For example, controller 144 may be configured to control the rotational speed and position of magnet assembly 136 and the current flowing through lower magnet assembly 142 and / or upper magnet assembly 140 during processing. Controller 144 includes a central processing unit (CPU) 146, memory 148, and support circuitry 150. Controller 144 may directly control PVD chamber 100 or be controlled by a computer (or controller) associated with a specific processing chamber and / or support system components. Controller 144 may be one of any type of general-purpose computer processor that can be used in an industrial environment to control various chambers and subprocessors. The memory or computer-readable medium 148 of the controller 144 may be one or more readily available memories, such as random access memory (RAM), read-only memory (ROM), floppy disk, hard disk, optical storage media (e.g., optical disc or digital video disc), flash memory disk, or any other form of local or remote digital storage. Support circuitry 150 is coupled to the central processing unit 146 to support the processor in a conventional manner. Such circuitry includes cache memory, power supply, clock circuitry, input / output circuitry systems, and subsystems. Methods and / or processes for controlling the PVD chamber 100 may be stored as software routines in the memory 148, which may be executed or invoked to control the operation of the PVD chamber 100 in the manner described herein. The software routines may also be stored and / or executed by a second central processing unit (not shown) located remotely from the hardware controlled by the central processing unit 146.

[0034] Figure 2 depicts a schematic cross-sectional view of the magnetron assembly 104 at a first fixed angular position according to some embodiments of this disclosure, the first fixed angular position having the innermost of a plurality of different fixed radii, such as the smallest fixed radius. The first fixed radius R1 is defined as the distance between the central axis 154 and the center of the magnet assembly 136 when the magnet assembly 136 is in the first fixed angular position. In some embodiments, the first fixed radius R1 is about 1.5 inches to about 2.6 inches.

[0035] Figure 3A depicts a schematic bottom view of a magnetron assembly 104 according to some embodiments of this disclosure. Figure 3A depicts a magnet assembly 136 rotated from a first fixed angular position to a second fixed angular position. For example, in some embodiments, the second fixed angular position may be set by rotating the magnet assembly 136 about 50 degrees to about 70 degrees relative to a first fixed radius R1 about an offset axis 172, as shown in Figure 2. The second fixed radius R2 is defined as the distance between the central axis 154 and the center of the magnet assembly 136 when the magnet assembly 136 is in the second fixed angular position. In some embodiments, the second fixed radius R2 is about 1.5 inches to about 2.6 inches.

[0036] Figure 3B depicts a schematic bottom view of a magnetron assembly 104 according to some embodiments of this disclosure. Figure 3B depicts a magnet assembly 136 rotated from a second fixed angular position to a third fixed angular position. For example, in some embodiments, the third fixed angular position may be set by rotating the magnet assembly 136 about 60 degrees to about 80 degrees relative to a first fixed radius R1 about an offset axis 172, as shown in Figure 2. The third fixed radius R3 is defined as the distance between the central axis 154 and the center of the magnet assembly 136 when the magnet assembly 136 is in the third fixed angular position. In some embodiments, the third fixed radius R3 is about 3.1 inches to about 3.3 inches.

[0037] Figure 3C depicts a schematic bottom view of a magnetron assembly 104 according to some embodiments of this disclosure. Figure 3A depicts a magnet assembly 136 rotated from a third fixed angular position to a fourth fixed angular position. For example, in some embodiments, the fourth fixed angular position can be set by rotating the magnet assembly 136 about 80 degrees to about 90 degrees relative to a first fixed radius R1 about an offset axis 172, as shown in Figure 2. The fourth fixed radius R4 is defined as the distance between the central axis 154 and the center of the magnet assembly 136 when the magnet assembly 136 is in the fourth fixed angular position. In some embodiments, the fourth fixed radius R4 is about 4.5 inches to 5.5 inches.

[0038] Figure 4 depicts magnet assembly 136 rotated approximately 180 degrees about offset axis 172 relative to the first fixed radius R1, as shown in Figure 2. Figure 4 shows magnet assembly 136 located at the fifth fixed radius, or radially outermost position, where the fifth fixed radius R5 is approximately 5.9 inches to 7.5 inches. Magnet assembly 136 can be rotated about offset axis 172 to position magnet assembly 136 at the second, third, and fourth fixed radii.

[0039] Referring back to Figure 2, in some embodiments, the support device 134 of the magnetron assembly 104 includes a base plate 202 having a first side 232 and a second side 234 opposite to the first side. The base plate 202 includes a central axis that coincides with the central axis 154 of the target. In some embodiments, the diameter of the base plate 202 is larger than the diameter of the target 116. In some embodiments, the base plate 202 is a generally flat circular plate. In some embodiments, the support device 134 includes a magnet plate 204 rotatably coupled to the base plate 202 on the first side 232. An offset axis 172 is generally located at the center of the magnet plate 204. In some embodiments, the magnet plate 204 does not extend along the central axis 154. In some embodiments, the distance 210 between the central axis 154 and the offset axis 172 is about 4.0 inches to about 5.0 inches. In some embodiments, the distance 250 between the offset axis 172 and the center of the magnet assembly 136 is about 2.0 inches to 3.0 inches.

[0040] In some embodiments, the magnetron assembly 104 includes a gearbox 208 for housing one or more gears, shafts, etc., to allow the magnet assembly 136 to rotate about a central axis 154 and an offset axis 172. For example, a first motor 174 may be coupled to a shaft (not shown) to rotate a base plate 202 (and the magnet assembly 136 coupled thereto) about the central axis 154. A second motor 178 may be coupled to a shaft (not shown) to rotate a magnet plate 204 (and the magnet assembly 136 coupled thereto) about the offset axis 172. The second motor 178 rotates the magnet plate 204 to control the angular position of the magnet assembly 136 and to position the magnet assembly 136 at each of a plurality of fixed angular positions (e.g., a first fixed angular position, a second fixed angular position, etc.), which define a plurality of different fixed radii. Once the magnet assembly 136 is positioned at each of the plurality of fixed angular positions, the second motor 178 stops the rotation of the magnet plate 204, and the first motor 174 continues to rotate the base plate 202 about the central axis 154, such that the magnet assembly 136 is configured to rotate 360 ​​degrees about the central axis 154 at each of the plurality of different fixed radii.

[0041] In some embodiments, the base plate 202 includes a through-hole 218 for a position sensor. A block 206 may be mounted to a second side 234 of the base plate 202 to support the position sensor 216. In some embodiments, the magnet plate 204 includes a lower plate 220 coupled to an upper plate 224. The lower plate 220 is coupled to the magnet assembly 136, and the upper plate 224 is coupled to the base plate 202. In some embodiments, the upper plate 224 is smaller than the lower plate 220, or includes cutouts to expose a flag 226 disposed on or embedded in the upper surface of the lower plate 220. The flag 226 may be any component or material capable of triggering the position sensor 216 when there is a line of sight between the position sensor 216 and the flag 226. For example, Figure 2 depicts a magnet plate 204 positioned such that the flag 226 aligns with the through-hole 218 of the base plate 202, triggering the magnet assembly to the position sensor 216 at one of a plurality of different fixed radii, such as a first fixed radius.

[0042] In some embodiments, when the magnet assembly is positioned at a first fixed radius, the magnet assembly 136 is positioned at approximately 180 degrees relative to the offset axis 172 and the position sensor 216. In some embodiments, when the magnet assembly is positioned at a fifth fixed radius, the magnet assembly 136 is positioned at approximately 0 degrees relative to the offset axis 172 and the position sensor 216.

[0043] In some embodiments, a first counterweight 212 is coupled to the base plate 202 about the central axis 154 and opposite to the magnet plate 204 to compensate for the weight of the magnet plate 204 and the magnet assembly 136. In some embodiments, a second counterweight 214 is coupled to the magnet plate 204 about the offset axis 172 on the side opposite to the magnet assembly 136 to compensate for the weight of the magnet assembly 136.

[0044] Figure 5 illustrates a flowchart of a method 500 for depositing a metal film onto a substrate (e.g., substrate 110) in a PVD chamber according to some embodiments of this disclosure. In some embodiments, the metal may include copper, titanium, tantalum, tungsten, etc. In some embodiments, method 500 includes depositing a metal film on a through silicon via (TSV). A DC power supply (e.g., DC power supply 128) provides DC power to a target to sputter the target, thereby depositing material onto the substrate. In some embodiments, the DC power supply provides about 30 kW to about 50 kW of DC power. In some embodiments, the DC power supply provides about 35 kW to about 40 kW of DC power.

[0045] In method 502, method 500 includes positioning a magnet assembly (e.g., magnet assembly 136) in a PVD cavity (e.g., PVD cavity 100) by rotating a magnet assembly about an offset axis (e.g., offset axis 172) to a first fixed radius relative to the central axis (e.g., central axis 154) of a target (e.g., target 112). In some embodiments, the first fixed radius is about 1.5 inches to about 2.6 inches. In some embodiments, the first fixed radius is about 2.3 inches to about 2.5 inches.

[0046] In method 504, method 500 includes depositing a metal film onto a substrate disposed opposite a target in a PVD chamber while rotating a magnet assembly relative to a central axis by a first fixed radius for a first time period. In some embodiments, the deposition rate of the metal film on the substrate is about 85 to about 105 angstroms / second while rotating the magnet assembly by the first fixed radius. In some embodiments, an radio frequency bias power of about 1.9 kW to about 2.1 kW is applied to a substrate support assembly (e.g., substrate support assembly 192) of the PVD chamber while the metal film is deposited by the first fixed radius.

[0047] In some embodiments, when a metal film is deposited at a first fixed radius, an upper magnet assembly (e.g., upper magnet assembly 140) disposed around the chamber body of the PVD chamber is supplied with a current of about 11.0 amps to about 15.0 amps. In some embodiments, a lower magnet assembly (e.g., lower magnet assembly 142) disposed around the chamber body may include a top inner magnet (e.g., top inner magnet A), a top outer magnet (e.g., top outer magnet B), and a bottom inner magnet (e.g., bottom inner magnet C). In some embodiments, the top outer magnet and the top inner magnet are supplied with a current of about -7.0 amps to about -1.0 amps while a metal film is deposited at the first fixed radius. In some embodiments, when a metal film is deposited at the first fixed radius, the bottom inner magnet is supplied with a current of about 7.0 amps to about 11.0 amps.

[0048] In method 506, method 500 includes positioning the magnet assembly at a second fixed radius relative to the central axis by rotating the magnet assembly about an offset axis. In some embodiments, the second fixed radius is about 2.6 inches to about 3.5 inches. In some embodiments, the second fixed radius is about 3.1 inches to about 3.3 inches.

[0049] In method 508, method 500 includes depositing a metal film on a substrate while rotating a magnet assembly relative to a central axis by a second fixed radius for a second time period. The second time period may be the same as or different from the first time period. In some embodiments, the deposition rate of the metal film on the substrate is about 95 to about 115 angstroms / second while rotating the magnet assembly by the second fixed radius. In some embodiments, an radio frequency bias power of about 1.9 kW to about 2.1 kW is applied to the substrate support assembly of the PVD chamber while the metal film is deposited at the second fixed radius.

[0050] In some embodiments, when a metal film is deposited at the second fixed radius, a current of about 13.0 amps to about 17.0 amps is supplied to the upward magnet assembly. In some embodiments, a current of about -8.0 amps to about -12.0 amps is supplied to the top outer magnet and the top inner magnet while a metal film is deposited at the second fixed radius. In some embodiments, when a metal film is deposited at the second fixed radius, a current of about 8.0 amps to about 12.0 amps is supplied to the bottom inner magnet.

[0051] In method 500, at 510, the method includes positioning the magnet assembly at a third fixed radius relative to the central axis by rotating the magnet assembly about an offset axis. In some embodiments, the third fixed radius is about 3.5 inches to about 4.5 inches. In some embodiments, the third fixed radius is about 4.1 inches to about 4.3 inches.

[0052] In 512, method 500 includes depositing a metal film onto a substrate while rotating a magnet assembly relative to a central axis by a third fixed radius for a third time period. In some embodiments, the third time period is similar to at least one of a first time period or a second time period. In some embodiments, the third time period is different from each of the first and second time periods. In some embodiments, the deposition rate of the metal film on the substrate is about 75 to about 95 angstroms / second while rotating the magnet assembly by the third fixed radius. In some embodiments, an radio frequency bias power of about 2.1 kW to about 2.3 kW is applied to a substrate support assembly of a PVD chamber while the metal film is deposited at the third fixed radius.

[0053] In some embodiments, a current of about 12.0 amps to about 16.0 amps is supplied to the upward magnet assembly while a metal film is deposited at a third fixed radius. In some embodiments, a current of about 14.0 amps to about 18.0 amps is supplied to the top outer magnet and the top inner magnet while a metal film is deposited at a third fixed radius. In some embodiments, a current of about -14.0 amps to about -18.0 amps is supplied to the bottom inner magnet while a metal film is deposited at a third fixed radius.

[0054] In 514, method 500 includes positioning the magnet assembly to a fourth fixed radius relative to the central axis by rotating the magnet assembly about an offset axis. In some embodiments, the fourth fixed radius is about 4.5 inches to about 5.5 inches. In some embodiments, the fourth fixed radius is about 4.9 inches to about 5.1 inches.

[0055] In 516, method 500 includes depositing a metal film onto a substrate while rotating a magnet assembly relative to a central axis by a fourth fixed radius for a fourth time period. In some embodiments, the fourth time period is similar to at least one of a first time period, a second time period, or a third time period. In some embodiments, the fourth time period is different from each of the first, second, and third time periods. In some embodiments, the deposition rate of the metal film on the substrate is about 115 to about 135 s / angstrom / s while rotating the magnet assembly by the fourth fixed radius. In some embodiments, an RF bias power of about 2.1 kW to about 2.3 kW is applied to a substrate support assembly of a PVD chamber while the metal film is deposited at the fourth fixed radius.

[0056] In some embodiments, an upward current of about 10.0 amps to about 14.0 amps is supplied to the upward magnet assembly while a metal film is deposited at a fourth fixed radius. In some embodiments, an upward current of about 14.0 amps to about 18.0 amps is supplied to the top outer magnet and the top inner magnet while a metal film is deposited at a fourth fixed radius. In some embodiments, a downward current of about -14.0 amps to about -18.0 amps is supplied to the bottom inner magnet while a metal film is deposited at a fourth fixed radius.

[0057] In 518, method 500 includes positioning the magnet assembly at a fifth fixed radius relative to the central axis by rotating the magnet assembly about an offset axis. In some embodiments, the fifth fixed radius is about 5.9 inches to about 7.5 inches. In some embodiments, the fifth fixed radius is about 6.0 inches to about 6.7 inches.

[0058] In method 500, at 520, the method includes depositing a metal film onto a substrate while rotating a magnet assembly relative to a central axis by a fifth fixed radius for a fifth time period. In some embodiments, the fifth time period is similar to at least one of a first time period, a second time period, a third time period, or a fourth time period. In some embodiments, the fifth time period is different from each of the first, second, third, and fourth time periods. In some embodiments, the deposition rate of the metal film on the substrate is about 80 to about 100 angstroms per second while rotating the magnet assembly by the fifth fixed radius. In some embodiments, an RF bias power of about 2.1 kW to about 2.3 kW is applied to a substrate support assembly of a PVD chamber while the metal film is deposited at the fifth fixed radius.

[0059] In some embodiments, a current of about 5.0 amps to about 9.0 amps is supplied to the upward magnet assembly while a metal film is deposited at a fifth fixed radius. In some embodiments, a current of about 10.0 amps to about 14.0 amps is supplied to the top outer magnet and the top inner magnet while a metal film is deposited at the fifth fixed radius. In some embodiments, a current of about -10.0 amps to about -14.0 amps is supplied to the bottom inner magnet while a metal film is deposited at the fifth fixed radius.

[0060] The metal film can be deposited on the substrate at any of the five radii in any order. For example, in some embodiments, the metal film is deposited on the substrate at a first fixed radius, then a second fixed radius, then a third fixed radius, then a fourth fixed radius, and then a fifth fixed radius. In some embodiments, the metal film is deposited on the substrate at a fifth fixed radius, then a fourth fixed radius, then a third fixed radius, then a second fixed radius, and then a first fixed radius. In some embodiments, the deposition rate of the metal film on the substrate is greater when the magnet assembly is at the first fixed radius than when the magnet assembly is at the fifth position.

[0061] Despite the foregoing description of the embodiments disclosed herein, other and further embodiments of this disclosure may be designed without departing from the basic scope of this disclosure.

[0062] 100: PVD chamber 102: Main body of the chamber 104: Magnetron Assembly 106: Substrate support base 108:ESC 110:Substrate 112: Target 114: Backplate 118: Processing Space 120: Sedimentary ring 122: Cover ring 124: Grounding ring 126: Radio Frequency Bias Power Supply 128: DC power supply 130: Main body 132: Coolant Supply 134: Supporting equipment 136: Magnet assembly 140: Upper magnet assembly 142: Lower magnet assembly 144: Controller 146: Central Processing Unit 148: Memory 150: Support circuit 152: Cover 154: Central Axis 156: Sputtered surface 160: Manifold section 166: Coolant Supply 168: Entrance 170: Streamline 172: Offset Axis 174: First electric motor 178: Second electric motor 182: Pump 186: Deposition cavity 190: Source 192: Substrate support assembly 194: Cavity 196: points 198:Top surface 202: Base Plate 204: Magnet Plate 206: blocks 208: Gearbox 210: Distance 212: First counterweight 214: Second counterweight 216: Position sensor 218: Through hole 220: Lower board 224:On the board 226: Flag 232: First side 234: Second side 250: Distance 500: Methods 502: Steps 504: Steps 506: Steps 508: Steps 510: Steps 512: Steps 514: Steps 516: Steps 518: Steps 520: Steps R1: First fixed radius R2: Second fixed radius R3: Third fixed radius R4: Fourth fixed radius R5: Fifth Fixed Radius

[0063] Domestic storage information (please note in order of storage institution, date, and number) none Overseas storage information (please note in the order of storage country, institution, date, and number) none

Claims

1. A magnetron assembly for a PVD chamber, comprising: A base plate having a first side, a second side opposite to the first side, and a central axis; A magnet plate rotatably coupled to the base plate on the first side thereof, wherein the magnet plate rotates relative to the base plate about an offset axis; a magnet assembly coupled to the magnet plate offset from the offset axis and configured to rotate about the central axis and the offset axis; a first motor coupled to the base plate to rotate the magnet assembly about the central axis; and a second motor coupled to the magnet plate to control its angular position and position the magnet assembly at each of a plurality of fixed angular positions defining a plurality of different fixed radii, wherein the magnet assembly is configured to rotate 360 ​​degrees about the central axis at each of the plurality of fixed radii.

2. The magnetron assembly as claimed in claim 1, wherein the magnet assembly is configured to rotate approximately 180 degrees about the offset axis from a zero-degree position to position the magnet assembly at each of the plurality of different fixed radii.

3. The magnetron assembly as claimed in claim 1, further comprising a counterweight connected to the base plate about the central axis and opposite to the magnet plate.

4. The magnetron assembly as claimed in claim 1, further comprising a counterweight coupled to the magnet plate on the side opposite to the magnet assembly about the offset axis.

5. The magnetron assembly as claimed in claim 1, wherein, When the magnet assembly is positioned at an angle of approximately 180 degrees to a position sensor relative to the offset axis, the magnet assembly is positioned at a first fixed radius, which corresponds to the innermost radial position of the magnet assembly relative to the central axis.

6. The magnetron assembly of any one of claims 1 to 5, wherein the plurality of different fixed radii include a first fixed radius of about 1.5 inches to about 2.6 inches, a second fixed radius of about 2.6 inches to about 3.5 inches, a third fixed radius of about 3.5 inches to about 4.5 inches, a fourth fixed radius of about 4.5 inches to about 5.5 inches, and a fifth fixed radius of about 5.9 inches to about 7.5 inches.

7. The magnetron assembly of any one of claims 1 to 5, wherein the distance between the central axis and the offset axis is about 4.0 inches to about 5.0 inches.

8. The magnetron assembly of any one of claims 1 to 5, wherein the distance between the offset axis and a center of the magnet assembly is about 2.0 inches to about 3.0 inches.

9. A method for depositing a metal film on a substrate, comprising the steps of: placing a magnet assembly at a first fixed radius relative to a central axis of a target in a physical vapor deposition (PVD) chamber; depositing a metal film onto the substrate disposed opposite to the target in the PVD chamber while rotating the magnet assembly relative to the central axis at the first fixed radius for a first time period; positioning the magnet assembly at a second fixed radius relative to the central axis by rotating the magnet assembly about an offset axis; and depositing a metal film onto the substrate while rotating the magnet assembly relative to the central axis at the second fixed radius for a second time period.

10. The method of claim 9, further comprising the steps of: positioning the magnet assembly at a third fixed radius relative to the central axis by rotating the magnet assembly about the offset axis; depositing a metal film onto the substrate while rotating the magnet assembly about the third fixed radius relative to the central axis for a third time period; positioning the magnet assembly at a fourth fixed radius relative to the central axis by rotating the magnet assembly about the offset axis; depositing a metal film onto the substrate while rotating the magnet assembly about the fourth fixed radius relative to the central axis for a fourth time period; positioning the magnet assembly at a fifth fixed radius relative to the central axis by rotating the magnet assembly about the offset axis; and depositing a metal film onto the substrate while rotating the magnet assembly about the fifth fixed radius relative to the central axis for a fifth time period.

11. The method of claim 10, wherein the metal film is deposited on the substrate at the first fixed radius, then the second fixed radius, then the third fixed radius, then the fourth fixed radius, and then the fifth fixed radius.

12. The method of claim 10, wherein the first fixed radius is about 1.5 inches to about 2.6 inches, the second fixed radius is about 2.6 inches to about 3.5 inches, the third fixed radius is about 3.5 inches to about 4.5 inches, the fourth fixed radius is about 4.5 inches to about 5.5 inches, and the fifth fixed radius is about 5.9 inches to about 7.5 inches.

13. The method of any one of claims 9 to 12, further comprising the step of: simultaneously depositing a metal film at the first fixed radius, applying a radio frequency bias power to a substrate support assembly of the PVD chamber at a frequency of about 2.0 kW to about 2.2 kW.

14. The method of any one of claims 9 to 12, further comprising the step of: while depositing a metal film at the first fixed radius and the second fixed radius, supplying a current of about 6.0 amperes to about 16.0 amperes to an upper magnet assembly disposed around a chamber body of the PVD chamber.

15. A non-transitory computer-readable medium for storing computer instructions, which, when executed by at least one processor, cause the at least one processor to perform a method comprising the steps of: positioning a magnetic assembly at a first fixed radius relative to a central axis of a target in a physical vapor deposition (PVD) chamber; depositing a metal film onto a substrate disposed opposite to the target in the PVD chamber while rotating the magnetic assembly relative to the central axis by the first fixed radius for a first time period; positioning the magnetic assembly at a second fixed radius relative to the central axis by rotating the magnetic assembly about an offset axis; and depositing a metal film onto the substrate while rotating the magnetic assembly relative to the central axis by the second fixed radius for a second time period.

16. The non-transitory computer-readable medium as described in claim 15, further comprising: By rotating the magnet assembly around the offset axis, the magnet assembly is positioned at a third fixed radius relative to the central axis; while rotating the magnet assembly relative to the central axis at the third fixed radius for a third time period, a metal film is deposited on the substrate; by rotating the magnet assembly around the offset axis, the magnet assembly is positioned at a fourth fixed radius relative to the central axis; while rotating the magnet assembly relative to the central axis at the fourth fixed radius for a fourth time period, a metal film is deposited on the substrate; by rotating the magnet assembly around the offset axis, the magnet assembly is positioned at a fifth fixed radius relative to the central axis; and while rotating the magnet assembly relative to the central axis at the fifth fixed radius for a fifth time period, a metal film is deposited on the substrate.

17. The non-transitory computer-readable medium as claimed in claim 16, wherein the metal film is deposited on the substrate at the first fixed radius, then the second fixed radius, then the third fixed radius, then the fourth fixed radius, and then the fifth fixed radius.

18. The non-transitory computer-readable medium as claimed in claim 16, wherein the first fixed radius is about 1.5 inches to about 2.6 inches, the second fixed radius is about 2.6 inches to about 3.5 inches, the third fixed radius is about 3.5 inches to about 4.5 inches, the fourth fixed radius is about 4.5 inches to about 5.5 inches, and the fifth fixed radius is about 5.9 inches to about 7.5 inches.

19. The non-transitory computer-readable medium as claimed in any one of claims 15 to 18, further comprising applying a radio frequency bias power to a substrate support assembly of the PVD chamber at a frequency of about 2.0 kW to about 2.2 kW while depositing a metal film at the first fixed radius.

20. The non-transitory computer-readable medium as claimed in any one of claims 15 to 18, further comprising, while depositing a metal film at the first fixed radius and the second fixed radius, supplying a current of about 6.0 amperes to about 16.0 amperes to an upper magnet assembly disposed around a chamber body of the PVD chamber.

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