Plating, and particularly electroplating, is a process by which conductive structures are formed on a semiconductor wafer. Plating may include applying a voltage across an anode formed of a plating material and a cathode (e.g., a semiconductor wafer). The voltage causes a current to oxidize the anode, which causes the release of plating material ions from the anode. These plating material ions form a plating solution that travels through a plating bath toward the semiconductor wafer. The plating solution reaches the semiconductor wafer and deposits plating material ions into trenches, vias, interconnects, and/or other structures in and/or on the semiconductor wafer.
Aspects of the present disclosure are best understood from the following detailed description when read with the accompanying figures. It is noted that, in accordance with the standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion.
The following disclosure provides many different embodiments, or examples, for implementing different features of the provided subject matter. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. For example, the formation of a first feature over or on a second feature in the description that follows may include embodiments in which the first and second features are formed in direct contact, and may also include embodiments in which additional features may be formed between the first and second features, such that the first and second features may not be in direct contact. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed.
Further, spatially relative terms, such as “beneath,” “below,” “lower,” “above,” “upper” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. The spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. The apparatus may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein may likewise be interpreted accordingly.
In some cases, a plating tool (e.g., a tool that is used to plate semiconductor wafers) may include a plating membrane. The plating membrane may be used to reduce and/or prevent additives in a plating solution from reaching an anode. While additives may be used to improve the plating process, additives that reach the anode may react with the anode and cause the formation of undesirable byproducts in the plating solution. The plating membrane may include a filter that permits the passage of plating material but prevents passage of additives. Accordingly, the filter of the plating membrane may be used to reduce and/or prevent additives from reaching the anode while still permitting plating material from the anode to pass through the plating membrane and plate the wafer.
However, the plating membrane may cause disruptions in the flow of the plating solution from a nozzle that directs the flow of the plating solution toward the wafer. For example, the plating membrane may cause turbulence in the flow, which can decrease the ability of the nozzle to direct the flow of the plating solution toward the wafer. As a result, the plating solution may be unable to penetrate into structures (particularly, deep and/or high aspect-ratio structures) in and/or on the wafer, which can cause voids in these structures. These voids can cause decreased conductivity, decreased reliability, and/or decreases in other electrical performance characteristics.
Some implementations described herein provide a plating membrane that includes a frame having an inner wall that is angled outward from a plating tool nozzle. The outward angle of the inner wall relative to the nozzle directs a flow of plating solution from the nozzle in a manner that increases uniformity of the flow of the plating solution toward a wafer, reduces the amount of plating solution that is redirected inward toward the center of the plating membrane, reduces plating material voids in trenches, vias, interconnects, and/or other structures in and/or on the wafer.
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In some implementations, plating membrane 100 may be other various shapes, such as oval shaped, square shaped, rectangular shaped, non-uniform shaped, non-standard shaped, and/or the like, and support structure 102 may be configured accordingly to support filter 104 and frame 106. In some implementations, support structure may be integrated with nozzle 108 such that plating membrane 100 and nozzle 108 are a single part or component. In some implementations, support structure 102 may be referred to as a skeleton, a web, or another type of structure that is capable of supporting filter 104 and/or frame 106.
Filter 104 includes a semi-permeable membrane or another type of filter that is capable of permitting the flow of the plating material through filter 104 while filtering, reducing, and/or preventing the flow of plating solution additives through filter 104. Filter 104 may be positioned such that filter 104 is capable of filtering plating solution that flows through the area between nozzle 108 and frame 106. In some implementations, filter 104 is attached to a bottom side or underside of support structure 102. In some implementations, filter 104 is attached to a top side or upper side of support structure 102. In some implementations, filter 104 includes a plurality of filter elements positioned in open areas of support structure 102 formed between support members 102a and/or support ring(s) 102b. In some implementations, filter 104 is attached to a bottom side or underside of support structure 102. In some implementations, filter 104 is integrated with support structure 102 such that filter 104 and support structure 102 are a single and/or unified part.
Frame 106 may be circular or substantially circular (or ring) shaped so as to provide an even flow path of plating material dispensed from nozzle 108. Frame 106 may further provide support and/or rigidity to plating membrane 100, which may increase the strength of plating membrane 100. Further, frame 106 may provide an attachment point for plating membrane 100 to be attached or connected to a wall of the plating tool to prevent movement of plating membrane 100.
Plating membrane 100, and/or support structure 102, filter 104, and frame 106 included therein, may be formed of various materials. The material(s) of plating membrane 100, and/or support structure 102, filter 104, and frame 106 included therein, may be selected so as to provide strength and and/or rigidity to plating membrane 100, to meet and/or increase reliability and longevity requirements, to reduce and/or minimize negative or undesirable reactions with intended use plating materials and/or additives, and/or the like.
As shown in the cross-sectional view in
In some implementations, the outward angle of inner wall 112 may be defined or identified from various reference points of plating membrane 100. For example, the angle of inner wall 112 may be defined relative to the center of plating membrane 100. In these cases, the outward angle of inner wall 112 may be greater than 0° and less than 90°. As another example, and as illustrated in a closeup view 110 in
In this way, plating membrane 100 includes frame 106 having inner wall 112 that is angled outward and away from a nozzle 108 and/or a center of plating membrane 100. The outward angle of inner wall 112 relative to nozzle 108 directs a flow of plating solution from nozzle 108 in a manner that increases uniformity of the flow of the plating solution toward a wafer, reduces the amount of plating solution that is redirected inward toward the center of plating membrane 100, and/or reduces plating material voids in trenches, vias, interconnects, and/or other structures in and/or on the wafer.
As indicated above,
Example flow pattern 200 illustrates an example flow of plating solution from a nozzle of a plating tool toward a wafer that is to be plated. As shown in
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A plating tool 402 may include a tool that plates a wafer 404 (e.g., a semiconductor wafer, an insulating wafer, and/or another type of wafer). As shown in
Plating material 412 and anode 418 include various types of conductive materials, metals, and/or the like. For example, plating material 412 and anode 418 may include copper, aluminum, nickel, tin, tin-lead, tin-silver, and/or another type of material. Additives 414 include various types of levelers, brighteners or accelerators, inhibitors, suppressors, enhancers, and/or other types of organic and/or inorganic additives that may be used to increase or decrease deposition rates of plating material 412 on wafer 404, reduce surface roughness of plating material 412 deposited onto wafer 404, and/or the like.
Plating membrane 420 may include plating membrane 100 illustrated and described above in connection with
Nozzle 422 includes an elongated cylindrical structure or another type of elongated structure to direct the flow of plating solution 410 toward wafer 404. In some implementations, nozzle 422 may dispense plating solution 410 provided via return line(s) 424. In this way, plating solution 410 may be circulated through plating bath 408 and reused. Pump 426 includes any one of various types of pumps that are capable of pumping a liquid from return line(s) 424 and through nozzle 422.
Controller 428 may include a processor, a computer (e.g., a desktop computer, a laptop computer, a tablet computer, a server, and/or the like), and/or another device capable of controlling various devices and/or components of plating tool 402. For example, controller 428 may be connected to power supply 416, and is capable of causing power supply 416 to apply a voltage across anode 418 and wafer 404, is capable of causing power supply 416 to stop applying a voltage across anode 418 and wafer 404, is capable of changing the voltage applied by power supply 416, and/or the like.
As another example, controller 428 may be connected to pump 426 and may cause pump 426 to pump plating solution 410 from return line(s) 424 to nozzle 422, may cause pump 426 to stop pumping plating solution 410, may adjust the speed or rate at which plating solution 410 is pumped through nozzle 422, and/or the like. As another example, controller 428 may be connected to wafer holder 406 and may cause wafer holder 406 to lower wafer 404 into plating bath 408, may case wafer holder 406 to rotate wafer 404 while wafer 404 is at least partially submerged in plating bath 408 (e.g., to increase the coverage and uniformity of plating material 412 on wafer 404), may cause wafer holder 406 to raise wafer 404 out of plating bath 408, and/or the like.
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In some implementations, each plating tool 402 may include devices and/or components illustrated in
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The number and arrangement of devices and networks shown in
Bus 510 includes a component that permits communication among multiple components of device 500. Processor 520 is implemented in hardware, firmware, and/or a combination of hardware and software. Processor 520 is a central processing unit (CPU), a graphics processing unit (GPU), an accelerated processing unit (APU), a microprocessor, a microcontroller, a digital signal processor (DSP), a field-programmable gate array (FPGA), an application-specific integrated circuit (ASIC), or another type of processing component. In some implementations, processor 520 includes one or more processors capable of being programmed to perform a function. Memory 530 includes a random access memory (RAM), a read only memory (ROM), and/or another type of dynamic or static storage device (e.g., a flash memory, a magnetic memory, and/or an optical memory) that stores information and/or instructions for use by processor 520.
Storage component 540 stores information and/or software related to the operation and use of device 500. For example, storage component 540 may include a hard disk (e.g., a magnetic disk, an optical disk, and/or a magneto-optic disk), a solid state drive (SSD), a compact disc (CD), a digital versatile disc (DVD), a floppy disk, a cartridge, a magnetic tape, and/or another type of non-transitory computer-readable medium, along with a corresponding drive.
Input component 550 includes a component that permits device 500 to receive information, such as via user input (e.g., a touch screen display, a keyboard, a keypad, a mouse, a button, a switch, and/or a microphone). Additionally, or alternatively, input component HW50 may include a component for determining location (e.g., a global positioning system (GPS) component) and/or a sensor (e.g., an accelerometer, a gyroscope, an actuator, another type of positional or environmental sensor, and/or the like). Output component 560 includes a component that provides output information from device 500 (via, e.g., a display, a speaker, a haptic feedback component, an audio or visual indicator, and/or the like).
Communication interface 570 includes a transceiver-like component (e.g., a transceiver, a separate receiver, a separate transmitter, and/or the like) that enables device 500 to communicate with other devices, such as via a wired connection, a wireless connection, or a combination of wired and wireless connections. Communication interface 570 may permit device 500 to receive information from another device and/or provide information to another device. For example, communication interface 570 may include an Ethernet interface, an optical interface, a coaxial interface, an infrared interface, a radio frequency (RF) interface, a universal serial bus (USB) interface, a Wi-Fi interface, a cellular network interface, and/or the like.
Device 500 may perform one or more processes described herein. Device 500 may perform these processes based on processor 520 executing software instructions stored by a non-transitory computer-readable medium, such as memory 530 and/or storage component 540. As used herein, the term “computer-readable medium” refers to a non-transitory memory device. A memory device includes memory space within a single physical storage device or memory space spread across multiple physical storage devices.
Software instructions may be read into memory 530 and/or storage component 540 from another computer-readable medium or from another device via communication interface 570. When executed, software instructions stored in memory 530 and/or storage component 540 may cause processor 520 to perform one or more processes described herein. Additionally, or alternatively, hardware circuitry may be used in place of or in combination with software instructions to perform one or more processes described herein. Thus, implementations described herein are not limited to any specific combination of hardware circuitry and software.
The number and arrangement of components shown in
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Process 600 may include additional implementations, such as any single implementation or any combination of implementations described below and/or in connection with one or more other processes described elsewhere herein.
In a first implementation, the voltage applied to the anode causes oxidation of the anode, which causes plating material ions to be released from the anode. In a second implementation, alone or in combination with the first implementation, causing the plating solution to be directed toward the wafer includes causing a pump (e.g., pump 426) to cause the plating solution to flow through the nozzle and toward the wafer. In a third implementation, alone or in combination with one or more if the first or second implementations, the outward angle of the inner wall of the plating membrane directs the flow of plating solution from the nozzle in a manner that increases uniformity of the flow of the plating solution toward the wafer.
In a fourth implementation, alone or in combination with one or more if the first through third implementations, the outward angle of the inner wall of the plating membrane reduces the amount of plating solution that is redirected inward toward the center of the plating membrane. In a fifth implementation, alone or in combination with one or more if the first through fourth implementations, the outward angle of the inner wall of the plating membrane reduces plating material voids in structures (e.g., plated structures 302) of the wafer (e.g., high aspect ratio trenches). In a sixth implementation, alone or in combination with one or more if the first through fifth implementations, process 600 includes causing a wafer holder (e.g., wafer holder 406) to rotate the wafer while the wafer is at least partially submerged in the plating solution.
Although
In this way, a plating membrane (e.g., plating membrane 100, plating membrane 420, and/or the like) includes a frame (e.g., frame 106) having an inner wall (e.g., inner wall 112, and/or the like) that is angled outward from a plating tool nozzle (e.g., nozzle 108, nozzle 422, and/or the like). The outward angle of the inner wall relative to the nozzle directs a flow of plating solution (e.g., plating solution 410 and/or the like) from the nozzle in a manner that increases uniformity of the flow of the plating solution toward a wafer (e.g., wafer 404 and/or the like), reduces the amount of plating solution that is redirected inward toward the center of the plating membrane, reduces plating material voids in various types of structures (e.g., plated structures 302) in and/or on the wafer, such as trenches, vias, interconnects, and/or the like.
As described in greater detail above, some implementations described herein provide a plating membrane. The plating membrane includes a support structure extending radially outward from a nozzle that is to direct a flow of a plating solution toward a wafer. The plating membrane includes a frame, supported by the support structure, having an inner wall that is angled outward from the nozzle.
As described in greater detail above, some implementations described herein provide a plating membrane. The plating membrane includes plating solution toward a wafer. The plating membrane includes a frame, supported by the support structure, having an inner wall that is angled radially outward from the nozzle to direct the flow of the plating solution radially outward from the nozzle and to reduce an amount of the plating solution that is redirected inward toward a center of the plating membrane.
As described in greater detail above, some implementations described herein provide a plating tool. The plating tool includes a nozzle and a plating membrane. The nozzle is positioned substantially at the center of the plating membrane and is to direct a flow of a plating solution in a plating bath toward a wafer. The plating membrane includes a support structure extending radially outward from the nozzle. The plating membrane includes a frame, attached to and supported by the support structure, having an inner wall that is angled away from a center of the plating membrane.
The foregoing outlines features of several embodiments so that those skilled in the art may better understand the aspects of the present disclosure. Those skilled in the art should appreciate that they may readily use the present disclosure as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein. Those skilled in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the present disclosure, and that they may make various changes, substitutions, and alterations herein without departing from the spirit and scope of the present disclosure.
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Number | Date | Country | |
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20210388523 A1 | Dec 2021 | US |