Physical vapor deposition source and chamber assembly

Abstract

Described herein are apparatus and methods for improving film uniformity in physical vapor deposition (PVD) processes, and in some embodiments, the magnetron translation assembly comprises: a first linear actuator assembly, the first linear actuator assembly comprising: a first rail aligned in a first direction; a first actuator configured to position a first mount along the first rail; a magnet assembly mounted on the first mount, the magnet assembly constructed and arranged to rotate about an axis perpendicular to the first rail; and a second linear actuator assembly, the second linear actuator assembly comprising: a second mount configured to be positioned along a second rail aligned in a second direction; and a second mount having the first linear actuator assembly coupled to a mounting surface of the second mount.

Description

[Technical Field]

[0001] Embodiments of the present disclosure relate generally to forming physical vapor deposition (PVD) films on substrates in electronic device manufacturing processes, and more particularly to an apparatus and method for improving film deposition uniformity by improving target utilization. [Background technology]

[0002] Today's electronic device manufacturing processes often involve the use of physical vapor deposition (PVD) or sputtering processes within a dedicated PVD chamber. The source of sputtered material can be a planar or rotating sputtering target made of pure metal, alloy, or ceramic material. A magnet array is used to generate a magnetic field near the target, typically located in an assembly often called a magnetron. A high voltage is applied to the target during processing to generate plasma and enable the sputtering process. Because the voltage source is negatively biased, the target is sometimes referred to as a "cathode." This high voltage generates an electric field inside the PVD chamber, which is used to enable sputtering of the target material and to generate and eject electrons from the target, which are used to generate and sustain plasma near the underside of the target. The magnet array (e.g., magnetron) applies an external magnetic field that captures the electrons and confines the plasma near the target. The captured electrons then collide with gas atoms located within the processing region of the PVD chamber, potentially ionizing them. Collisions between the trapped electrons and gas atoms cause the gas atoms to release electrons, which are used to maintain and further increase plasma density in the processing region of the PVD chamber. The plasma may contain argon atoms, positively charged argon ions, free electrons, and ionized and neutral metal atoms sputtered from the target. The negative bias accelerates the argon ions toward the target, where they collide with the target's surface, thereby ejecting atoms of the target material from the target. The ejected atoms then travel toward the substrate and chamber shield to be incorporated into the thin film being grown thereon.

[0003] Controlling PVD sputtering and film uniformity is particularly challenging when processing large-area substrates such as panels. As used herein, the term "panel" may refer to a large-area substrate that includes a large surface area. For example, a typical panel size may be 600 mm x 600 mm. In some packaging applications, typical panel materials may include polymeric materials such as Ajinomoto Build-up Film (ABF), Copper Clad Laminate (CCL), polymer-topped panels, glass, or other similar materials.

[0004] PVD film formation on large-area substrates may be performed using either planar or rotating targets, as described above. In either case, the target size can be over 800 mm in length, and in some cases, even exceed 1,000 mm. In other words, the target size can be approximately 20% to 40% larger than the size of the substrate being processed. The need for such large-area targets presents particular challenges for PVD sputtering processes. For example, for precious metals, the amount of raw material required to manufacture such area targets makes them cost prohibitive. On the other hand, large-area monolithic targets formed from relatively brittle materials, such as silicon, are prone to cracking or breakage and are therefore difficult and expensive to manufacture. In addition, the size of conventional PVD chambers can only accommodate one large-area target at a time, which reduces throughput compared to what could be achieved if multiple targets were placed in the process chamber to provide uniform PVD film deposition across the surface of a panel or substrate. Due to purity and metal structure requirements, targets are generally expensive to manufacture. Moreover, conventional target and magnetron designs suffer from inefficient and / or non-uniform erosion of target material during the PVD deposition process, which is even more of a problem with non-circular and / or asymmetric target designs commonly used in multi-target PVD chamber designs, due to the need for complex movement of the magnetron over the target surface during processing.

[0005] Therefore, there is a need in the art for an apparatus and method for improving film deposition uniformity, which at the same time provides more efficient utilization of target material. Summary of the Invention

[0006] FIELD OF THE INVENTION The embodiments described herein generally relate to forming physical vapor deposition (PVD) films on substrates in electronic device manufacturing processes. More particularly, the embodiments described herein provide an apparatus and method for improving film uniformity by improving target material utilization.

[0007] In one embodiment, a magnetron translation assembly is provided, comprising a first linear actuator assembly having a first mount positioned along a first rail aligned in a first direction and a first actuator configured to position the first mount along the first rail. A second linear actuator assembly includes a second mount positioned along a second rail aligned in a second direction perpendicular to the first direction, with the first linear actuator assembly coupled to a mounting surface of the second mount. The second actuator is configured to position the second mount and the first linear actuator assembly along the second rail and a magnet assembly having inner and outer pole pieces oriented parallel to the plane and having opposite magnetic polarities. A rotary actuator is provided between the mounting surface of the first mount of the first linear actuator assembly and the magnet assembly, and the rotary actuator is configured to rotate the magnet assembly about an axis perpendicular to the plane.

[0008] In one embodiment, a physical vapor deposition (PVD) chamber comprises a magnetron translation assembly including a first linear actuator assembly having a magnet assembly mounted thereon and a second linear actuating assembly for supporting the first linear actuating assembly; a pedestal having an upper surface configured to support a substrate thereon is disposed within a processing region of the PVD chamber; a first motor is coupled to the pedestal and configured to rotate the pedestal about a second axis perpendicular to at least a portion of the upper surface of the pedestal; and a controller comprises a memory for storing a program, the program including instructions that, when executed by a processor of the controller, synchronize movement of the first and second linear actuators to move the magnet in a predetermined path.

[0009] A more particular description of the present disclosure briefly outlined above may be had by reference to embodiments, some of which are illustrated in the accompanying drawings, in a manner that allows the above-listed features of the disclosure to be understood in detail. It should be noted, however, that the accompanying drawings illustrate only typical embodiments of the present disclosure and therefore should not be considered as limiting in scope, as the present disclosure may embrace other embodiments that are equally effective. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a schematic top view of an exemplary substrate processing system, in accordance with certain embodiments. [Figure 2A] 2 is a cross-sectional side view of a PVD chamber including a magnetron translator assembly that may be used in the substrate processing system of FIG. 1 according to certain embodiments. [Figure 2B] 2 is a cross-sectional side view of a PVD chamber including two magnetron translator assemblies that may be used in the substrate processing system of FIG. 1, according to certain embodiments. [Figure 3]2B is an enlarged cross-sectional view of a portion of the PVD chamber of FIG. 2A showing a first linear actuating assembly of the magnetron translation assembly according to certain embodiments. [Figure 4] 4 is an enlarged cross-sectional view of a portion of the PVD chamber taken along line 4-4 of FIG. 3, showing a second linear actuating assembly of the magnetron translation assembly. [Figure 5A] 2B is a top view of a portion of FIG. 2A showing the first magnetron translation assembly above the rotating panel of the substrate. [Figure 5B] 2C is a top view of a portion of FIG. 2B showing the first and second magnetron translation assemblies above the rotating panel of the substrate. [Figure 5C] FIG. 13 shows the underside of a magnet assembly associated with the magnetron translator assembly. [Figure 6] FIG. 10 is a top view of the magnetron translator assembly over a delta-shaped target showing various positions of the magnet assembly relative to the translator assembly and target. [Figure 7] FIG. 10 is a top view of the magnetron translator assembly over a delta-shaped target showing various positions of the magnet assembly relative to the translator assembly and target. [Figure 8] FIG. 10 is a top view of the magnetron translator assembly over a delta-shaped target showing various positions of the magnet assembly relative to the translator assembly and target. [Figure 9] FIG. 10 is a top view of the magnetron translator assembly over a delta-shaped target showing various positions of the magnet assembly relative to the translator assembly and target. [Figure 10] FIG. 1 is a top view of a delta-shaped target showing one path of the magnet assembly over the target, the magnets being moved by the action of the magnetron translation assembly. [Figure 11] FIG. 11 is a top view of the delta-shaped target of FIG. 10 showing a more completed path of the magnet assembly. [Figure 12]FIG. 10 is a top view of a delta-shaped target showing an alternative path for the magnet assembly above the target. DETAILED DESCRIPTION OF THE INVENTION

[0011] For ease of understanding, where possible, identical reference numerals have been used to designate identical elements common to the figures. It is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without additional description.

[0012] FIELD OF THE INVENTION

[0003] The embodiments of the present disclosure described herein generally relate to physical vapor deposition (PVD) of thin films on substrates in electronic device manufacturing processes. More particularly, the embodiments described herein provide apparatus and methods for improving film deposition uniformity when using compact targets, also referred to herein as compact cathodes, cathodes, or targets. In some embodiments, to improve film uniformity using compact targets, the apparatus may include a substrate support element configured to rotate the substrate during processing. Compact targets reduce target costs compared to the large-area targets discussed above. The embodiments of the present disclosure described herein may provide targets tilted relative to the substrate being processed to improve film uniformity. The embodiments of the present disclosure described herein may further enable co-sputtering by using two or more targets simultaneously, which may increase throughput compared to using a single target and allow for tailoring of the composition of the deposited film. The embodiments of the present disclosure described herein may further enable translational motion of the magnetron in two approximately perpendicular directions to spread the magnetic field generated by the magnetron across the sputtering service area of ​​the target for full-surface erosion. Generally, the translational or vibrational motion helps manage defects such as particles and arcing and extends the life of the target compared to a stationary magnet, which only erodes certain areas of the target. The embodiments of the present disclosure described herein can further enable the magnetron to be scanned along one or more paths across the backside of the target so that the uniformity of the deposited film can be controlled. For example, the scanning of the magnetron may be adjusted during the deposition process to compensate for variations in film thickness across different areas of the substrate.

[0013] Exemplary Substrate Processing System FIG. 1 is a schematic top view of an exemplary substrate processing system 100 (also referred to as a “processing platform”) according to certain embodiments. In certain embodiments, the substrate processing system 100 is configured, among other things, to process large area substrates such as the panels described above. The substrate processing system 100 generally includes an Equipment Front End Module (EFEM) 102 for loading substrates into the processing system 100, a first load lock chamber 104 coupled to the EFEM 102, a transfer chamber 106 coupled to the first load lock chamber 104, and multiple other chambers coupled to the transfer chamber 106, which will be described in more detail below. The Front End Module (EFEM) 102 generally includes one or more robots 105 configured to transfer substrates from a FOUP 103 to at least one of the first load lock chamber 104 or the second load lock chamber 120. Proceeding counterclockwise from the first load lock chamber 104 along the transfer chamber 106, the processing system 100 includes a first dedicated degassing chamber 108, a first pre-cleaning chamber 110, a first deposition chamber 112, a second pre-cleaning chamber 114, a second deposition chamber 116, a second dedicated degassing chamber 118, and a second load lock chamber 120. In certain embodiments, the transfer chamber 106 and each chamber coupled to the transfer chamber 106 are maintained under vacuum. As used herein, the term "vacuum" can refer to a pressure below 760 Torr, and typically is less than about 10 -5 Torr (i.e., about 10 -3 However, some high vacuum systems are maintained at a pressure of about 10 -7 Torr (i.e., about 10 -5 The transfer chamber 106 may operate at pressures below 100 psi (Pa). In certain embodiments, this vacuum is generated using a roughing pump and / or turbomolecular pump coupled to the transfer chamber 106 and each of the one or more process chambers (e.g., process chambers 108-118). However, other types of vacuum pumps are also contemplated.

[0014] In certain embodiments, substrates are loaded into the processing system 100 through a door (also referred to as an "access port") of the first load lock chamber 104 and unloaded from the processing system 100 through a door of the second load lock chamber 120. In certain embodiments, a stack of substrates is supported in a cassette located within the FOUP, from which the substrates are transferred by the robot 105 to the first load lock chamber 104. After a vacuum is drawn within the first load lock chamber 104, the robot 107 located within the transfer chamber 106 is used to remove one substrate at a time from the load lock chamber 104. In certain embodiments, cassettes are located within the first load lock chamber 104 and / or the second load lock chamber 120 to allow multiple substrates to be stacked and held therein before being received by the robot 107 in the transfer chamber 106 or the robot 105 in the EFEM 102. However, other loading and unloading configurations are also contemplated.

[0015] Pre-cleaning of substrates is important to remove impurities from the substrate surface so that films (e.g., metal films) deposited in the deposition chambers are not electrically insulated from the conductive metal surface areas of the substrate by a layer of impurities, such as oxides. By performing pre-cleaning in the first and second pre-cleaning chambers 110, 114, which share a similar vacuum environment as the first and second deposition chambers 112, 116, the substrate can be transferred from the cleaning chambers to the deposition chambers without exposure to the atmosphere. This prevents impurities from forming on the substrate during transfer. Additionally, the vacuum in the substrate processing system 100 is maintained during transfer of the cleaned substrate to the deposition chamber, thereby reducing the number of vacuum pump-down cycles. In some embodiments, the processing system 100 may break the vacuum in one of the load lock chambers when the cassette in the first load lock chamber 104 or the second load lock chamber 120 is empty or full, allowing one or more substrates to be added or removed from it.

[0016] In certain embodiments, only one substrate is processed at a time in each preclean chamber and deposition chamber. Alternatively, multiple substrates, such as four to six substrates, may be processed at a time. In such embodiments, multiple substrates may be placed on a rotatable pallet within each chamber. In certain embodiments, the first and second preclean chambers 110, 114 are inductively coupled plasma (ICP) chambers for etching the substrate surface. However, other types of preclean chambers are also contemplated. In certain embodiments, one or both of the preclean chambers are replaced with a film deposition chamber configured to perform a PVD, chemical vapor deposition (CVD), or atomic layer deposition (ALD) process, such as silicon nitride deposition.

[0017] In a precleaning chamber containing an ICP source, an external RF source energizes a coil at the top of the chamber to generate an excitation field within the chamber. A precleaning gas (e.g., argon, helium) from an external gas source flows through the chamber. Precleaning gas atoms within the chamber are ionized (charged) by the supplied RF energy. In some embodiments, the substrate is biased by an RF bias source. The charged atoms are attracted to the substrate, resulting in bombardment and / or etching of the substrate surface. Other gases in addition to argon may be used depending on the desired etch rate and the material being etched.

[0018] In certain embodiments, the first and second deposition chambers 112, 116 are PVD chambers. In such embodiments, the PVD chambers may be configured to deposit copper, titanium, aluminum, gold, and / or tantalum. However, other types of deposition processes and materials are also contemplated.

[0019] Exemplary PVD Chamber and Method of Use 2A and 2B are cross-sectional side views of a PVD chamber 200 that may be used in the substrate processing system 100 of FIG. 1 according to certain embodiments. For example, the PVD chamber 200 may represent either the first or second deposition chambers 112, 116 shown in FIG. 1. Alternatively, the PVD chamber 200 may represent an additional deposition chamber. FIG. 3 is an enlarged cross-sectional view of a portion of the PVD chamber 200 of FIG. 2A according to certain embodiments. Therefore, for clarity, FIGS. 2A, 2B, and 3 will be described together herein.

[0020] The PVD chamber 200 generally includes a chamber body 202, a lid assembly 204 coupled to the chamber body 202, a magnetron including a magnet assembly 575 within the lid assembly 204, a pedestal 210 disposed within the chamber body 202, and a target 212 disposed between the magnet assembly 575 and the pedestal 210. During processing, the interior, or processing region 237, of the PVD chamber 200 is maintained at a vacuum pressure. The processing region 237 is generally defined by the chamber body 202 and the lid assembly 204 such that the processing region 237 is primarily located between the target 212 and the substrate support surface of the pedestal 210.

[0021] A power supply 206 is electrically connected to the target 212 for applying a negatively biased voltage to the target 212. In certain embodiments, the power supply 206 is a straight DC mode source or a pulsed DC mode source, although other types of power supplies, such as radio frequency (RF) sources, are also contemplated.

[0022] The target 212 includes a target material 212M and a backing plate 218 and is part of the lid assembly 204. The front surface of the target material 212M of the target 212 defines a portion of the processing region 237. The backing plate 218 is disposed between the magnet assembly 575 and the target material 212M of the target 212 (FIG. 3), and in some embodiments, the target material 212M is coupled to the backing plate 218. Typically, the backing plate 218 is an integral part of the target 212; therefore, for simplicity of discussion, the pair may be collectively referred to as the “target.” To prevent electrical shorting between the backing plate 218 and the grounded support plate 213 of the lid assembly 204, the backing plate 218 is electrically isolated from the support plate 213 of the lid assembly 204 using an electrical insulator 215. As shown in FIGS. 2A and 2B , the backing plate 218 has a plurality of cooling channels 233 configured to receive a coolant (e.g., DI water) therethrough to cool or control the temperature of the target 212. In certain embodiments, the backing plate 218 may have one or more cooling channels. In some examples, the cooling channels 233 may be interconnected and / or form a serpentine path through the body of the backing plate 218. A shield 223 is coupled to the backing plate 213. The shield 223 prevents material sputtered from the target 212 from depositing a film on the backing plate 213. In some embodiments, the magnet assembly 575 and the target 212, including the target material 212M and the backing plate 218, each have a triangular or delta shape such that the sides of the target 212 include three corners (e.g., the three rounded corners shown in FIGS. 5-11 ). As shown in Figures 5A and 5B, target 212 is oriented so that the tip of one corner of the triangular or delta-shaped target is at or adjacent to central axis 291. When viewed in a planar orientation, the surface area of ​​target 212 is smaller than the surface area of ​​substrate 216, as shown in Figures 5A and 5B.In some embodiments, the surface area of ​​the top surface of the pedestal is greater than the surface area of ​​the front surface of the target 212. In some embodiments, the ratio of the surface area of ​​the front surface of the target 212 to the surface area of ​​the deposition surface of the substrate 216 (e.g., the top surface of the substrate) is between about 0.1 and about 0.4.

[0023] 2A and 2B, magnet assembly 575 is positioned above a portion of target 212 and within the atmospherically maintained region of lid assembly 204. Magnet poles 590, 595 of assembly 575 are arranged as one or more closed loops, each of which is associated with a permanent magnet positioned and oriented relative to its poles (i.e., north (N) and south (S) poles) such that the magnetic field extends from one magnet pole to the next or between different portions of the loop. In certain embodiments, magnet assembly 575 may include multiple electromagnets instead of permanent magnets utilized with magnet poles 590, 595.

[0024] The pedestal 210 has an upper surface 214 that supports a substrate 216. A clamp 224 is used to hold the substrate 216 to the upper surface 214. In certain embodiments, the clamp 224 is mechanically actuated. For example, the weight of the clamp 224 may hold the substrate 216 in place. In certain embodiments, the clamp 224 is elevated by a pin that is movable relative to the pedestal 210 so as to contact the underside of the clamp 224.

[0025] In this example, the backside of the substrate 216 is in contact with the top surface 214 of the pedestal 210. In some examples, the entire backside of the substrate 216 may be in electrical and thermal contact with the top surface 214 of the pedestal 210. A temperature control system 232 may be used to control the temperature of the substrate 216. In certain embodiments, the temperature control system 232 has an external cooling source that supplies coolant to the pedestal 210. In some embodiments, the external cooling source is configured to supply a cryogenically cooled fluid (e.g., Galden®) to heat exchange elements (e.g., coolant channels) in the substrate support portion of the pedestal 210 adjacent the top surface 214 to control the temperature of the substrate to a temperature below 20° C., e.g., below 0° C., e.g., about −20° C. or below. In certain embodiments, the temperature control system 232 includes a heat exchanger and / or a backside gas flow within the pedestal 210. In some examples, the cooling source may be replaced or augmented by a heating source to increase the workpiece temperature independently of the heat generated during the sputtering process. Controlling the temperature of the substrate 216 during the sputtering process is important to obtain predictable and reliable thin films. In certain embodiments, an RF bias source 234 is electrically coupled to the pedestal 210 to bias the substrate 216 during the sputtering process. Alternatively, the pedestal 210 may be grounded, floating, or biased solely with a DC voltage source. Biasing the substrate 216 may improve film density, adhesion, and material reactivity on the substrate surface.

[0026] A pedestal shaft 221 is coupled to the underside of the pedestal 210. A rotary union 219 is coupled to the lower end of the pedestal shaft 221 to provide a rotary fluid coupling to a temperature control system 232 and a rotary electrical coupling to an RF bias source 234. In certain embodiments, copper tubing is disposed through the pedestal shaft 221 to couple both fluids and electricity to the pedestal 210. The rotary union 219 includes a magnetic fluid rotary sealing mechanism (also referred to as a "Ferrofluidic® seal") for the vacuum rotary feedthrough.

[0027] In this example, the substrate 216 is a panel. In certain embodiments, the top surface 214 of the pedestal 210 accommodates a single square or rectangular panel substrate having sides of about 500 mm or greater, such as 510 mm x 515 mm or 600 mm x 600 mm. However, the apparatus and methods of the present disclosure may be practiced with many different types and sizes of substrates.

[0028] In certain embodiments, the pedestal 210 is rotatable about an axis 291 that is perpendicular to at least a portion of the top surface 214 of the pedestal 210. In this example, the pedestal 210 is rotatable about a vertical axis corresponding to the z-axis. In certain embodiments, the rotation of the pedestal 210 is continuous without indexing. In other words, the motor 231 that drives the rotation of the pedestal 210 does not have programmable stops for rotating the substrate 210 to a fixed rotational position. Instead, the pedestal 210 rotates continuously relative to the target 212 to improve film uniformity. In certain embodiments, the motor 231 is an electric servo motor. The motor 231 may be raised and lowered by a separate motor 215, which may be an electrically driven linear actuator. A bellows 217 surrounds the pedestal shaft and forms a seal between the chamber body 202 and the motor 231 during raising and lowering of the pedestal 210.

[0029] The lower surface of the target 212, defined by the surface of the target material 212M, faces toward the upper surface 214 of the pedestal 210 and the front surface of the substrate 216. The lower surface of the target 212 faces away from the backing plate 218, which faces toward the atmospheric or external region of the PVD chamber. In certain embodiments, the target material 212M of the target 212 is formed from a metal for sputtering a corresponding film composition onto the substrate 216. In one example, the target material 212M may include a pure material or an alloy including an element selected from the group consisting of copper (Cu), molybdenum (Mo), nickel (Ni), titanium (Ti), tantalum (Ta), aluminum (Al), cobalt (Co), gold (Au), silver (Ag), manganese (Mn), and silicon (Si). Materials deposited on substrate 216 by the methods described herein may include pure metals, doped metals, metal alloys, metal nitrides, metal oxides, metal carbides, and silicon-containing oxides, nitrides, or carbides containing these elements. In this example, pedestal 210 is substantially horizontal, or parallel to the xy plane, while target 212 is non-horizontal, or tilted relative to the xy plane. However, pedestal 210 with other non-horizontal orientations is also contemplated.

[0030] The magnetron translation assembly 500 is coupled to the lid assembly 204 and is shown in FIGS. 3 and 4 for clarity. In one embodiment, the assembly 500 and target 212 are tilted at an angle 586, as shown in FIG. 3. In certain embodiments, the angle 586 is between about 2° and about 10°, e.g., between about 3° and about 5°. The assembly 500 includes first and second linear actuator assemblies 510, 550, which in the illustrated embodiment are perpendicular to one another. The first linear actuator assembly 510 includes a first actuator 515, which in one embodiment includes a motor constructed and arranged to rotate a first lead screw 516 to provide linear movement to the first mount 520 along a first rail 525. In certain embodiments, the first actuator 515 is an electric motor. Alternatively, a pneumatic motor may be used. In some examples, the first actuator 515 and other actuators used in the assembly may be servo motors or stepper motors, or may be direct drive motors, belt drive motors, or gear drive motors.

[0031] A rotary actuator 570 is mounted below first mount 520 and a predetermined distance above target 212 to rotate a magnet assembly 575 mounted below rotary actuator 570. Magnet assembly 575 includes an array of magnets separately coupled to inner and outer poles 590 and 595. A longitudinal axis 571 of the rotary actuator is perpendicular to tilt angle 586 of first linear actuator assembly 510. By operating first actuator 515, lead screw 516 moves first mount 520 and magnet assembly 575 between first and second ends of first rail 525.

[0032] 4 is an enlarged cross-sectional view of a portion of the PVD chamber 200 taken along line 4-4 in FIG. 3, showing the second linear actuating assembly 550 of the magnetron translation assembly 500. In an effort to avoid confusion, the angle of the cut line 4-4 is oriented perpendicular to the face of the target 212, and therefore the angle of the cut line 4-4 is oriented at the tilt angle of the target 212 relative to the vertical (Z direction); therefore, the magnetron translation assembly 500 and the target 212 are shown in a horizontal orientation in FIG. 4. A second rail 565 extends between the first support 580 and the second support 585, and the second rail 565 includes a second mount 560 constructed and arranged to carry the first linear actuator assembly 510 along the second lead screw 517 by means of a second actuator 555. FIG. 5A is a top view of a portion of FIG. 2A showing the magnetron translator assembly 500 and target 212 above a rotating substrate 216. The direction of rotation is indicated by arrow 217. In the illustrated embodiment, the substrate 216 is a square panel. As shown in FIG. 5B, the process chamber 200 can include two magnetron translator assemblies 500, 700. The second assembly 700 includes its own first and second linear actuators 710, 750. In FIG. 5B, the magnet assemblies 575, 775 of each translator assembly 500, 700 are shown in the same position relative to the target 212, 712. However, since both assemblies 575, 775 are processing the same rotating substrate, it is understood that coordination between the two magnet assemblies 575, 775 may or may not place them in similar, different, and / or opposite positions at all times or at any one time. In one embodiment, both assemblies move in equal and opposite fashion across the target as shown in Figures 6-9. However, in another embodiment, the magnet assemblies 575, 775 operate on different portions of their targets 212, 712 and do not share a path, which would result in twice the amount of sputtered material being applied to the same area of ​​the substrate.In some embodiments, the position and movement of the magnet assembly 575, 775 are process variables, in addition to the rotational speed, linear velocity, and distance of the magnet from the target 212.

[0033] One goal of the design of the magnetron translation assembly 500 is to facilitate uniform erosion of target material in a manner that improves target utilization and more uniformly deposits material on the substrate 216. FIGS. 6-9 are top views of the magnetron translation assembly 500 over a delta-shaped target 212, illustrating various positions of the linear actuator assemblies 510, 550 and the magnet assembly 575 relative to the target 212. By combining the movements of the linear actuating assemblies 510, 550, the rotating magnet assembly 575 can be moved over the target 212 in a manner that ensures uniform erosion of the target material and achieves uniformity of the deposited material on the rotating substrate. It should be noted that uniform target erosion does not necessarily ensure uniform deposition on the substrate during the substrate deposition process. Therefore, it is believed that coordinating the translational movement of the magnet assembly 575 over an asymmetric target with the rotational speed of the substrate can achieve two competing deposition process goals (i.e., uniform target erosion and uniform deposition).

[0034] FIG. 5C illustrates the underside of a magnet assembly 575 associated with the magnetron translation assembly 500. The circular end shapes of the inner and outer magnet poles 590, 595 and the distance 594 from the centerline of the magnet assembly to the centerline 593 or center of gravity of the magnet poles are shown. Because the magnet poles are positioned on one side of the magnetron assembly 575 (i.e., asymmetrically positioned and offset about axis 571), the rotational speed of the assembly can be important for uniform removal of target material; by correlating the rotation of the assembly 575 with the linear velocity of the assembly 575 across the target 212, uniform exposure to the portion of the plasma formed above the target surface can be controlled by controlling the translation and rotation of the magnetron assembly 575. In addition to the rotational speed of the magnet assembly 575 about axis 571, the spacing distance 597 (FIGS. 3 and 4) of the magnet poles relative to the target surface can also be important in determining the strength of the magnetic field and, therefore, the density of the plasma generated above the target surface. In one embodiment, this distance is set in coordination with the linear translation and rotational speed of the magnetron assembly 575 to achieve a predetermined deposition rate of the target material onto the substrate.

[0035] In FIG. 6 , the magnet assembly 575 has been translated to one end of the first linear assembly 510 by the operation of the actuator 575, while the second assembly 550 is at its midpoint. This positioning of the components places the magnet assembly 575 over one of the three corners of the target 212, ensuring that target material from the corner region 212 a is deposited onto the rotating substrate (not shown) below. In FIG. 7 , the magnet assembly 575 has been moved along the first rail 525 of the first actuator assembly 510 to a position near the center of the first actuator assembly 510, while the first actuator assembly 510 itself has been translated away from its position over the corner region 212 a by the operation of the actuator 555 and moved toward one side of the target 212. FIG. 8 shows a position of the translation assembly 500 in which the magnet assembly 575 has been moved across the center of the target 212 and positioned near the opposite side. 9, the first and second linear actuator assemblies 510, 550 of the translation assembly 500 position the magnet assembly 575 over the second corner region 212b of the delta-shaped target 212. FIGS. 6-9 show that the magnetron translation assembly 500 can use its first and second linear actuator assemblies 510, 550 to position the magnet assembly 575 over any portion of the target while maintaining a predetermined spacing between the lower surfaces of the magnet poles 590, 595 and the upper surface of the target. The lead screw and motor ensure smooth movement of the magnet assemblies, thereby ensuring smooth and uniform removal of target material and more uniform and predictable deposition of target material onto the substrate.

[0036] FIG. 10 is a top view of the delta-shaped target 212, illustrating one path 600 of the magnet assembly 575 (not shown) over the target 212 as a result of operation of the magnetron translation assembly 500. In the illustrated example, the magnet assembly 575 is initially positioned at a starting point 600s over one corner region 212a of the target 212. The starting point 600s corresponds to the position of the magnet assembly in FIG. 6. Operation of the first and second linear actuator assemblies 510, 550 then causes the magnet assembly to move in a serpentine pattern having progressively longer arc-shaped portions 604a-f and curved end portions 602a-f to an end position 600e between the remaining two corners 212b, 212c of the target 212. The varying lengths of the curved end portions 602a-f correspond to the widening shape of the target as the path 600 progresses from the starting point 600s to the end point 600e. As shown, the serpentine path includes a radial component and a circumferential component, the circumferential component forming a delta shape as the serpentine path extends in the direction of increasing radius.

[0037] 11 is a top view of the delta-shaped target 212 of FIG. 10 showing an additional path 620 of the magnet assembly 575 beginning at a point 620s adjacent the end point 600e of the path 600 and extending to a point 620e adjacent the beginning point 600s of the path 600. For clarity, the previously formed path 600 is shown in dashed lines.

[0038] 10 and 11 together, a second path 620 begins at location 620s and moves back toward corner region 212a in the same serpentine fashion, with progressively shorter arcuate portions 624a-f and curved end portions 622a-f. The arcuate portions of path 620 retrace the paths of original linear portions 604a-f, while the curved end portions 622a-f follow portions of the target untouched by original path 600.

[0039] The magnet moves in a serpentine pattern from the corner region 212a of the target 212 to the opposite, wider end, and then returns to the corner region 212a on a slightly deviated path to form a complete path. The result is a series of increasingly wider arc-shaped formations between each linear segment. The uniform path 600 of the magnet assembly across the target 212 provides an evenly uniform distribution of material as it is deposited on a substrate below the target. As described above, during the deposition process, the substrate rotates at a predetermined speed on the pedestal 210. Simultaneously, the magnetron translation assembly 500 moves the magnet assembly 575 over the delta-shaped target 212, as shown in FIGS. 6-9, to generate target erosion patterns such as those shown in FIGS. 10 and 11.

[0040] FIG. 12 is a top view of the delta-shaped target 212 showing alternative paths 600, 620 of the magnet assembly 575 above the target. For clarity, the initially formed path 600, having arc-shaped portions and curved end portions 602a-e, is shown in dashed lines. Similar to FIG. 11, the path 600 begins at corner region 212a (600s) and terminates at midpoint 600e between corner regions 212b and 212c. Unlike the embodiments of FIGS. 10 and 11, the second path 620 in this embodiment does not partially retrace the initial path; rather, it forms an entirely new path from start point 620s to end point 620e adjacent corner region 212a of the target 212. As illustrated by this figure, the paths, particularly the arc-shaped portions, are independent, except for the intersection of the paths at curved end portions 622a-f. The result is more efficient removal of target material without producing grove-shaped formations on the surface of the target due to paths sharing the same route above the target.

[0041] The primary purpose of the magnetron translation assembly 500 is to facilitate movement and positioning of the magnet assembly 575 over the target 212 while the underlying substrate 216 rotates on the pedestal 210. The presence of the first linear actuator assembly 510 and the second linear actuator assembly 550 allows for fluid and continuous movement to ensure a smooth erosion rate of the target material and a corresponding smooth deposition of material on various areas of the substrate 216. In addition to the linear movement of the magnet assembly 575, the speed at which the magnet assembly 575 moves across the substrate is another variable that can be addressed by the translation assembly 500. For example, increasing or decreasing the speed of the first and / or second actuators will speed or slow the movement of the magnet assembly 575 during the deposition process. This feature is particularly useful for compensating for different rotational speeds of various portions of a rotating substrate.

[0042] Returning to FIG. 5A , the magnet assembly 575 is shown positioned near the centerline 291 of the substrate 216. As the substrate rotates in the counterclockwise direction 217, it moves past the target 212 at a first rotational or angular velocity. However, as the magnet assembly 575 translates toward the opposite end of the first linear actuator 510, the angular velocity of the substrate increases, which can affect deposition uniformity due to the short time the magnet assembly must erode the target 212 above the moving substrate 216. In one embodiment, the system controller 250, described below, can be programmed to increase or decrease the translational velocity of the magnet assembly across the substrate 216, as determined by the distance of the magnet assembly from the centerline 291. Alternatively, the system controller 250 can be programmed to synchronize the rotational speed of the pedestal motor 231 with the position of the magnet assembly 575 to increase or decrease the rotational speed of the substrate, as determined by the position of the magnet assembly 575. This operation described with respect to the single FIG. 5A is equally applicable to the arrangement having two magnetron translating assemblies 500, 700 shown and discussed with respect to FIG. 5B.

[0043] A system controller 250, such as a programmable computer, is coupled to the PVD chamber 200 to control the PVD chamber 200 or components of the PVD chamber 200. For example, the system controller 250 may control the operation of the PVD chamber 200 using direct control of the power supply 206, the magnetron 208, the pedestal 210, the cooling of the backing plate 218, the first actuator 220, the second actuator 222, the temperature control system 232, and / or the RF bias source 234, or using indirect control of other controllers associated with the system controller 250. In operation, the system controller 250 enables data acquisition and feedback from each component to regulate processing within the PVD chamber 200.

[0044] The system controller 250 includes a programmable central processing unit (CPU) 252 operable with memory 254 (e.g., non-volatile memory) and support circuits 256. The support circuits 256 (e.g., cache, clock circuits, input / output subsystems, power supplies, etc., and combinations thereof) are conventionally coupled to the CPU 252 and to the various components of the PVD chamber 200.

[0045] In some embodiments, CPU 252 is one of any form of general-purpose computer processor, such as a programmable logic controller (PLC), used in industrial environments to control various monitoring system components and sub-processors. Memory 254 coupled to CPU 252 is non-transitory and is typically one or more of readily available memory, such as local or remote random access memory (RAM), read-only memory (ROM), floppy disk drive, hard disk, or any other form of digital storage.

[0046] As used herein, memory 254 takes the form of a computer-readable storage medium (e.g., non-volatile memory) containing instructions that, when executed by CPU 252, facilitate operation of PVD chamber 200. The instructions in memory 254 take the form of a program product (e.g., a middleware application, an instrument software application, etc.), such as a program that implements the methods of the present disclosure. The program code may conform to any one of several different programming languages. In one example, the present disclosure may be implemented as a program product stored on a computer-readable storage medium for use with a computer system. The programs in the program product define functions of embodiments (including the methods described herein).

[0047] Exemplary computer-readable storage media include, but are not limited to, (i) non-writable storage media having information permanently stored thereon (e.g., a read-only memory device within a computer, such as a CD-ROM disk readable by a CD-ROM drive, a flash memory, a ROM chip, or any type of solid-state non-volatile semiconductor memory), and (ii) writable storage media having changeable information stored thereon (e.g., a floppy disk or hard disk drive within a diskette drive, or any type of solid-state random access semiconductor memory). Such computer-readable storage media, when containing computer-readable instructions that direct the functions of the methods described herein, are embodiments of the present disclosure.

[0048] During operation, the PVD chamber 200 is evacuated and refilled with argon gas. The power supply 206 applies a negative bias voltage to the target 212, generating an electric field inside the chamber body 202. This electric field acts to attract gas ions, which generate electrons through collisions with the exposed surface of the target 212. These electrons allow a high-density plasma to be generated and maintained near the underside of the target 212. The plasma is concentrated near the surface of the target material 212M due to the magnetic field generated by the magnetron 208. This magnetic field creates a closed-loop annular path that acts as an electron trap, reshaping the trajectories of secondary electrons emitted from the target material 212M into a cycloidal path, significantly increasing the ionization probability of the sputtering gas within the confinement zone. The plasma confined near the underside of the target 212 contains argon atoms, positively charged argon ions, free electrons, and neutral atoms (i.e., unionized atoms) sputtered from the target material 212M. Argon ions in the plasma strike the target surface, liberating atoms of the target material, which are accelerated towards the substrate 216 and deposit a thin film on the substrate surface.

[0049] Inert gases such as argon are commonly used as sputtering gases because they tend not to react with the target material or combine with the process gases, and because their relatively high molecular weight results in higher sputtering and deposition rates.

[0050] While the foregoing is directed to embodiments of the present disclosure, other and additional embodiments of the disclosure may be devised without departing from the basic scope thereof, the scope of which is determined by the claims that follow.

Claims

1. 1. A magnetron translating assembly, comprising: a first linear actuator assembly, the first linear actuator assembly comprising: a first mount configured to be positioned along a first rail aligned in a first direction; a first actuator configured to position the first mount along the first rail; a first linear actuator assembly comprising: a second linear actuator assembly, the second linear actuator assembly comprising: a second mount configured to be positioned along a second rail aligned in a second direction perpendicular to the first direction, the second mount having the first linear actuator assembly coupled to a mounting surface of the second mount; a second actuator configured to position the second mount and the first linear actuator assembly along the second rail; and a second linear actuator assembly comprising: a magnet assembly comprising an inner pole having an inner pole piece and an outer pole having an outer pole piece, the inner pole piece and the outer pole piece being oriented parallel to a plane, the inner pole piece and the outer pole piece having opposite magnetic polarities; a rotary actuator coupled between a mounting surface of the first mount of the first linear actuator assembly and the magnet assembly, the rotary actuator configured to rotate the magnet assembly about an axis perpendicular to the plane; and 1. A magnetron translating assembly comprising:

2. The magnetron translator assembly of claim 1 , wherein the magnet assembly is disposed above a surface of a target.

3. 3. The magnetron translating assembly of claim 2, wherein the surface of the target is parallel to the plane, and the plane is at a first angle with respect to a central axis of a physical vapor deposition (PVD) chamber on which the magnetron translating assembly is disposed.

4. 4. The magnetron translating assembly of claim 3, wherein the central axis is perpendicular to a top surface of a pedestal disposed within the PVD chamber.

5. 5. The magnetron translation assembly of claim 4, wherein the second rail of the linear actuator assembly is supported by supports located at each end of the second rail, each of the supports positioned at substantially the same radial distance from the central axis.

6. The magnetron translating assembly of claim 3 , wherein the first angle is between about 2° and about 10°.

7. The magnetron translation assembly of claim 1 , wherein the first actuator positions the first mount along the first rail by a first lead screw.

8. The magnetron translation assembly of claim 7 , wherein the second actuator positions the second mount along the second rail by a second lead screw.

9. 1. A physical vapor deposition (PVD) chamber, comprising: a magnetron translating assembly, the magnetron translating assembly comprising: a first linear actuator assembly, the first linear actuator assembly comprising: a first mount configured to be positioned along a first rail aligned in a first direction; a first actuator configured to position the first mount along the first rail; a first linear actuator assembly comprising: a second linear actuator assembly, the second linear actuator assembly comprising: a second mount configured to be positioned along a second rail aligned in a second direction perpendicular to the first direction, the second mount having the first linear actuator assembly coupled to a mounting surface of the second mount; a second actuator configured to position the second mount and the first linear actuator assembly along the second rail; and a second linear actuator assembly comprising: a magnet assembly comprising an inner pole having an inner pole piece and an outer pole having an outer pole piece, the inner pole piece and the outer pole piece being oriented parallel to a plane, the inner pole piece and the outer pole piece having opposite magnetic polarities; a rotary actuator coupled between a mounting surface of the first mount of the first linear actuator assembly and the magnet assembly, the rotary actuator configured to rotate the magnet assembly about a first axis perpendicular to the plane; and a magnetron translating assembly comprising: a pedestal disposed within a processing region of the PVD chamber, the pedestal having an upper surface configured to support a substrate thereon; a first motor coupled to the pedestal, the first motor configured to rotate the pedestal about a second axis perpendicular to at least a portion of the top surface of the pedestal; 1. A controller comprising a memory for storing a program, the program including instructions that, when executed by a processor of the controller, using the first actuator to move the first mount and rotational actuator along the first rail; and said moving said second mount, said first linear actuator assembly, and said rotary actuator along said second rail using said second actuator; the rotation of the magnet assembly about the first axis, the first axis and a second axis being non-parallel; Synchronize the controller and A physical vapor deposition (PVD) chamber comprising:

10. 10. The physical vapor deposition (PVD) chamber of claim 9, wherein the command causes the magnet assembly to follow a serpentine path above the plane.

11. 11. The physical vapor deposition (PVD) chamber of claim 10, wherein the serpentine path includes a radial component extending from the second axis and a circumferential component forming a delta shape as the serpentine path extends in a direction of increasing radius from the second axis.

12. 12. The physical vapor deposition (PVD) chamber of claim 11, wherein the serpentine path begins at a first corner of the delta shape and ends between a second corner and a third corner, the first corner being closest to the second axis.

13. further comprising a second magnetron translating assembly, the second magnetron translating assembly comprising: a first linear actuator assembly, the first linear actuator assembly comprising: a first mount configured to be positioned along a first rail aligned in a first direction; a first actuator configured to position the first mount along the first rail; a first linear actuator assembly comprising: a second linear actuator assembly, the second linear actuator assembly comprising: a second mount configured to be positioned along a second rail aligned in a second direction perpendicular to the first direction, the second mount having the first linear actuator assembly coupled to a mounting surface of the second mount; a second actuator configured to position the second mount and the first linear actuator assembly along the second rail; and a second linear actuator assembly comprising: a magnet assembly comprising an inner pole having an inner pole piece and an outer pole having an outer pole piece, the inner pole piece and the outer pole piece being oriented parallel to a plane, the inner pole piece and the outer pole piece having opposite magnetic polarities; a rotary actuator coupled between a mounting surface of the first mount of the first linear actuator assembly and the magnet assembly, the rotary actuator configured to rotate the magnet assembly about a first axis perpendicular to the plane; and 10. The physical vapor deposition (PVD) chamber of claim 1, comprising:

14. 10. The physical vapor deposition (PVD) chamber of claim 1, further comprising a rotary union coupled to a pedestal, the rotary union configured to provide a fluid coupling to the pedestal during rotation of the pedestal about the first axis.

15. 15. The physical vapor deposition (PVD) chamber of claim 14, wherein the top surface of the pedestal is configured to receive a square or rectangular substrate having sides with lengths of about 500 mm or greater.

16. 1. A magnetron translating assembly, comprising: a first linear actuator assembly, the first linear actuator assembly comprising: a first rail aligned in a first direction; a first actuator configured to position a first mount along the first rail; a magnet assembly mounted on the first mount, the magnet assembly constructed and arranged to rotate about an axis perpendicular to the first rail; a first linear actuator assembly comprising: a second linear actuator assembly, the second linear actuator assembly comprising: a second mount configured to be positioned along a second rail aligned in a second direction, the first linear actuator assembly coupled to a mounting surface of the second mount; a second linear actuator assembly comprising:

1. A magnetron translating assembly comprising:

17. 17. The magnetron translating assembly of claim 16, wherein the first direction is perpendicular to the second direction.

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