Patent Application
20250205848
This application claims benefit of and priority to Indian Provisional Patent Application No. 202341087672, filed Dec. 21, 2023, the entire contents of which are incorporated herein by reference.
Embodiments of the present disclosure generally relate to polishing systems for polishing substrates, such as semiconductor substrates.
Chemical mechanical planarization (CMP) is one process commonly used in the manufacture of high-density integrated circuits to planarize or polish a layer of material formed on a substrate. CMP is performed by providing contact between a feature-containing side of the substrate and a polishing pad by moving the substrate relative to a polishing pad while in the presence of a polishing fluid.
The CMP polishing system can include a polishing head to hold the substrate and apply pressure to the substrate against the polishing pad during polishing. The polishing head generally includes a retaining ring disposed around the edges of the substrate to assist in holding the substrate in the polishing head. The polishing head also generally includes a flexible membrane positioned against the back side of the substrate during polishing. The pressure applied to the flexible membrane during polishing can be adjusted to change the pressure that is applied to the substrate against the polishing pad during polishing.
Although polishing processes can be performed within specifications when using polishing heads that include a retaining ring and flexible membrane, the retaining ring and flexible membrane begin to deform after repeated use and eventually these components must be replaced. Replacing these components can be costly due to the cost of the components themselves and due to the downtime required for the replacement. Thus, there is a need for an improved polishing system that can retain substrates and apply pressure during polishing without requiring frequent replacement of components (e.g., the retaining ring and flexible membrane) that results in increased operating costs as well as machine downtime during the replacement.
Embodiments of the present disclosure generally relate to equipment and related methods for improving the gas flow to process chambers, such as semiconductor process chambers.
In one embodiment, a polishing system for chemical mechanical planarization is provided including: a polishing head assembly that includes: a shaft; and a polishing head coupled to the shaft, the polishing head comprising: a housing having an interior volume; a distribution plate in the interior volume of the housing; and a first conduit extending through the shaft and the interior volume of the housing to the distribution plate, wherein the interior volume of the housing includes a first portion configured to receive a substrate below a bottom surface of the distribution plate with a back side of the substrate positioned at a first location when the substrate is retained in the polishing head, the distribution plate includes a first plurality of apertures fluidly coupled to the first conduit, the first plurality of apertures extend through the bottom surface of the distribution plate to the first portion of the interior volume, and a region extending from the first plurality of apertures to the first location of the back side of the substrate is free of obstructions.
In another embodiment, a polishing head for chemical mechanical planarization is provided comprising: a housing having an interior volume; a distribution plate in the interior volume of the housing; and a first conduit extending through the interior volume of the housing to the distribution plate, wherein the interior volume of the housing includes a first portion configured to receive a substrate below a bottom surface of the distribution plate with the back side of the substrate positioned at a first location when the substrate is retained in the polishing head, the distribution plate includes a first plurality of apertures fluidly coupled to the first conduit, the first plurality of apertures extend through the bottom surface of the distribution plate to the first portion of the interior volume, and a region extending from the first plurality of apertures to the first location of the back side of the substrate is free of obstructions.
In another embodiment, a method for polishing a substrate comprising: retaining a substrate in a polishing head in a first portion of an interior volume of the polishing head during a first time period by applying a first pressure to a first conduit coupled to a first plurality of apertures in a distribution plate of the polishing head, wherein the first plurality of apertures extend through a bottom surface of the distribution plate to the first portion of the interior volume; positioning the substrate retained in the polishing head against a polishing pad; and polishing the substrate by rotating a surface of the substrate against the polishing pad during a second time period occurring after the first time period while applying a second pressure to the first conduit that is coupled to the first plurality of apertures in the distribution plate, wherein the second pressure is greater than the first pressure.
So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only exemplary embodiments and are therefore not to be considered limiting of its scope, and may admit to other equally effective embodiments.
To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation.
Embodiments of the present disclosure generally relate to polishing systems for polishing substrates, such as semiconductor substrates. The polishing systems disclosed herein are configured to apply gas pressures including vacuum pressures and/or positive pressures directly to the back side of the substrate without a flexible membrane positioned against the back side of the substrate. Applying vacuum pressure (e.g., pressure less than 600 Torr) directly to the back side of the substrate allows the substrate to be retained in the polishing head without use of retaining rings that are typically used in conventional polishing heads. Because the polishing heads disclosed herein do not use the flexible membranes or retaining rings that are used in conventional CMP polishing heads, the costs and downtime associated with replacing these consumable components is avoided.
In the following disclosure, vacuum pressure and positive pressure, such as pressure greater than atmospheric pressure, can be applied directly to the back side of the substrate in the polishing head through apertures in a distribution plate in the polishing head. The polishing head can be configured to provide different pressures to different sets of apertures in the distribution plate of the polishing head, so that the pressure on the different portions of the back side of the substrate can be controlled independently during polishing. Using some of the apertures for applying vacuum pressure also allows the gas supplied to apply polishing pressure to the back side of the substrate to be removed from the volume between the back side of the substrate and the distribution plate.
Applying pressure directly to the back side of the substrate also allows more precise control of the pressure applied to different portions of the substrate because the limitations caused by the conventional flexible membrane are no longer present when the flexible membrane is not used. When a flexible membrane is used to apply pressure to the back side of a substrate, then the material can only stretch and deform so much relative to other portions of the flexible membrane. Because of these limitations, using a flexible membrane generally makes the pressure applied to different portions of the substrate more gradual even when a more abrupt pressure change (e.g., step change) between two different portions of the back side of the substrate would be beneficial for the polishing process being performed.
The polishing head assembly 101 includes a polishing head 110. The vacuum source 160 can be fluidly coupled to the polishing head 110 of the polishing head assembly 101, so that vacuum pressure can be applied to retain the substrate 50 in the polishing head 110. The gas source 170 can also be fluidly coupled to the polishing head 110, so that a gas supply pressure (e.g., a pressure greater than atmospheric pressure) can be applied to a back side 51 of the substrate 50 in the polishing head 110 to press the opposing surface 52 of the substrate 50 against the polishing pad 60 when the polishing of the substrate 50 is performed.
The controller 185 can be used to adjust when vacuum pressure from the vacuum source 160 is applied to the polishing head 110 and when gas supply pressure from the gas source 170 is applied to the polishing head 110. For example, before polishing of the substrate 50, vacuum pressure from the vacuum source 160 can be applied to the polishing head 110 without any gas supply pressure from the gas source 170, so that the substrate 50 is retained in the polishing head 110 and the substrate 50 can be moved into a polishing position by movement of the polishing head 110 by the rotatable arm 103 and vertical movement of the polishing head 110. During polishing of the substrate 50, vacuum pressure from the vacuum source 160 and gas pressure from the gas source 170 can be applied simultaneously to the polishing head 110, so that an appropriate amount of pressure can be applied to the back side 51 of the substrate 50 during polishing. After polishing of the substrate 50 and moving the substrate 50 to a transfer position, gas supply pressure from the gas source 170 can be applied to the polishing head 110 without any vacuum pressure from the vacuum source 160, so that the substrate 50 can be released from the polishing head 110.
The polishing pad assembly 150 includes a platen 151, a motor 152, and a shaft 153 coupled between the motor 152 and the platen 151. The motor 152 is configured to rotate the shaft 153 and the platen 151 coupled to the shaft 153 about a vertical axis 156 extending through the center of the shaft 153 and the platen 151 during polishing of the substrate 50. The polishing pad 60 is positioned on the platen 151. The polishing pad 60 rotates with the platen 151 during polishing of the substrate 50.
The polishing head assembly 101 includes a shaft 108, the polishing head 110, a rotary union 107, and a plurality of motors 102, 104, 106. The shaft 108 couples polishing head 110 to the rotary union 107. The rotary union 107 allows fluid connections from the vacuum source 160 and the gas source 170 to the polishing head 110 to be maintained as the shaft 108 and polishing head 110 are rotated during polishing of the substrate 50. The rotatable arm 103 can be rotated to position the polishing head 110 in different positions. For example, the rotatable arm 103 can move the polishing head 110 from a first position over the polishing pad assembly 150 enabling the substrate 50 to be polished to a second position over another support (not shown) where substrates can be exchanged by the polishing head 110.
The motors of the polishing head assembly 101 include a horizontal motor 102, a vertical motor 104, and a rotational motor 106. The horizontal motor 102 is configured to move the polishing head assembly 101 horizontally relative to a location on the rotatable arm 103, such as an end of the rotatable arm 103. The vertical motor 104 is configured to move the polishing head 110 vertically relative to the polishing pad assembly 150, for example to lower the substrate 50 in the polishing head 110 onto the polishing pad 60 to begin polishing or to raise the substrate 50 in the polishing head 110 away from the polishing pad 60 when polishing of the substrate 50 is completed. In some embodiments, the horizontal motor 102 and the vertical motor 104 can each be linear actuators.
The rotational motor 106 is configured to rotate the shaft 108 and the polishing head 110 that is coupled to the shaft 108, so that the substrate 50 retained in the polishing head 110 can be rotated against the polishing pad 60 during polishing of the substrate 50. The rotational motor 106 can be configured to rotate the shaft 108 and the polishing head 110 about a rotational axis 109 extending vertically through the centers of the polishing head 110 and the shaft 108.
The polishing head 110 includes a housing 111, a distribution plate 120, and an outer member 118. The housing 111 includes a top 112 and one or more sidewalls 113 connected to the top 112 of the housing 111. The housing 111 is disposed around an interior volume 115 of the polishing head 110.
The distribution plate 120 extends across the interior volume 115 of the housing 111 from the one or more sidewalls 113 of the housing 111. The distribution plate 120 can include a first plurality of apertures 121 and a second plurality of apertures 122. Although only two of each aperture 121, 122 are shown, some embodiments of the distribution plate 120 can include many more of each aperture 121, 122, such as greater than 50 or greater than 100 of each type of aperture 121, 122. The distribution plate 120 includes a bottom surface 125. The apertures 121, 122 extend to the bottom surface 125 of the distribution plate 120. The interior volume 115 includes a first portion 115A below the bottom surface 125 of the distribution plate 120. The first portion 115A is configured to receive the substrate 50. The substrate 50 is retained in the first portion 115A of the interior volume 115 during the polishing of the substrate 50. Different gas pressures can be applied through the apertures 121, 122 to the first portion 115A of the interior volume 115, so that these different pressures can be applied to different regions of the back side 51 of substrate 50 during polishing of the substrate 50 or other processes, such as moving and handling of the substrate 50 by the polishing head 110.
The back side 51 of the substrate 50 can be positioned at a first location 61 against the outer member 118 when the substrate 50 is retained in the polishing head 110. The region between the apertures 121, 122 and the back side 51 of the substrate 50 is free of obstructions, so that the gas pressure or vacuum pressure can be directed through the apertures 121, 122 directly to the back side 51 of the substrate 50 without intervening structures, such as the flexible membranes that are used in conventional polishing heads.
In some embodiments, some or all of the apertures 121, 122 can include one or more fins 129 or other structures to alter the flow of gas provided to the first portion 115A of the interior volume 115. The fins 129 can extend from the sidewalls that form the apertures 121, 122. Two exemplary fins 129 are shown on the aperture 122 on the right side of the polishing head 110. The fins 129 or similar structures can cause the gas provided through the aperture to the first portion 115A of the interior volume 115 to have a swirling motion as the gas exits the apertures 121, 122 into the first portion 115A of the interior volume 115. This swirling motion can help distribute the gas pressure applied through the apertures 121, 122 in the X and Y directions above the back side 51 of the substrate 50 in the first portion 115A of the interior volume 115.
Although the distribution plate 120 is referred to as a plate, some embodiments can include other structures (e.g., separate distribution rings or individual nozzles) that are capable of spacing apart the different sets of apertures for applying the vacuum pressure from the vacuum source 160 and the gas supply pressure from the gas source 170 to different regions over the back side 51 of the substrate 50. The distribution plate 120 can also be more generally referred to as a distributor.
The polishing system 100 further includes a first conduit 131 and a second conduit 132. The first conduit 131 is configured to fluidly couple the first plurality of apertures 121 in the polishing head 110 to vacuum pressure from the vacuum source 160 or to gas supply pressure from the gas source 170. The second conduit 132 is similarly configured to fluidly couple the second plurality of apertures 122 in the polishing head 110 to vacuum pressure from the vacuum source 160 or to gas supply pressure from the gas source 170. Although the first conduit 131 is fluidly coupled to all of the first plurality of apertures 121, only one connection to one aperture 121 is shown to not clutter the drawing. Similarly, although the second conduit 132 is fluidly coupled to all of the second plurality of apertures 122, only one connection to one aperture 122 is shown to not clutter the drawing. In some embodiments, the distribution plate 120 can include internal channels and/or plenums connecting each of the first plurality of apertures 121 to the first conduit 131 as well as internal channels and/or plenums connecting each of the second plurality of apertures 122 to the second conduit 132 while keeping the gas flow path through the first conduit 131 and the first plurality of apertures 121 independent from the gas flow path through the second conduit 132 and the second plurality of apertures 122.
The polishing head 110 further includes the outer member 118. The outer member 118 is positioned in the interior volume 115 of the housing 111 below the distribution plate 120. In some embodiments, the outer member 118 is connected to the one or more sidewalls 113 of the housing 111, the bottom surface 125 of the distribution plate 120, or to both. The outer member 118 is configured to make contact with the back side 51 of the substrate 50 during polishing. In some embodiments, the outer member 118 can have a ring shape. The outer member 118 can be sized to only contact the back side 51 of the substrate 50 near the outer edge 53 of the substrate 50, so that vacuum and/or gas supply pressure can be applied to the uncovered portions of the back side 51 of the substrate 50. Additionally, the one or more sidewalls 113 can be positioned to not contact the outer edge 53 of the substrate 50 when the substrate 50 is positioned in the polishing head 110. In some embodiments, the outer member 118 can be sized to have an opening that is slightly smaller than the diameter of the substrate being processed. For example, in some embodiments the diameter of the opening of the outer member 118 can be from about 1% to about 15% less than the diameter of the substrate, such as from about 2% to about 10% less than the diameter of the substrate being polished by the polishing head 110.
The outer member 118 can be configured to have a lower surface 119 with a relatively high coefficient of friction, so that the substrate 50 rotates with the outer member 118 without any slippage when the polishing head 110 is rotated by the rotational motor 106. In some embodiments, the lower surface 119 of the outer member 118 can be formed of natural rubber, a thermoplastic elastomer (TPE), thermoplastic polyurethane (TPU), or liquid silicone rubber (LSR). Vacuum pressure from the vacuum source 160 can be applied to one or more sets of apertures 121, 122 in the distribution plate 120 to pull the substrate 50 against the outer member 118, so that the substrate 50 rotates with the outer member 118 without any slippage when the polishing head 110 is rotated by the rotational motor 106. In some embodiments, the outer member 118 can also be formed of a material configured to form a seal with the back side 51 of the substrate 50, which can prevent polishing slurry or other materials from entering portions of the interior volume 115 above the substrate 50, such as regions exposed to the vacuum pressure that is applied to one or more of the apertures 121, 122.
When the substrate 50 is retained against the outer member 118, a gap G is formed between the back side 51 of the substrate 50 and the distribution plate 120. The gap G can have a vertical size in the Z-direction from about 10 micron to about 200 micron, such as from about 20 micron to about 100 micron. Keeping the size of the gap G in this range allows for separate pressure regions to be formed over the back side 51 of the substrate 50. On the other hand, larger gaps may allow for too much mixing of the gases provided through different sets of apertures for the separate pressure zones to be maintained. In some embodiments with additional sets of separately controlled apertures, five or more separate pressure zones (e.g. zones spaced apart in a center to edge radial direction) can be formed over the back side 51 of the substrate 50. Including the fins 129 in the apertures that can be used to create the swirling motion of the gas flow provided to the first portion 115A of the interior volume 115 can also help form the discrete pressure zones over the back side 51 of the substrate 50.
The polishing system 100 can further include a plurality of valves to control the application of vacuum pressure from the vacuum source 160 and gas supply pressure from the gas source 170 to the polishing head 110. The plurality of valves includes a plurality of shut-off valves V1-V4 that are configured to open and close. The first valve V1 is configured to open to apply vacuum pressure from the vacuum source 160 to the first conduit 131 and the first plurality of apertures 121 in the polishing head 110. The second valve V2 is configured to open to apply gas supply pressure from the gas source 170 to the second conduit 132 and the second plurality of apertures 122 in the polishing head 110. The third valve V3 is configured to open to apply vacuum pressure from the vacuum source 160 to the second conduit 132 and the second plurality of apertures 122 in the polishing head 110. The fourth valve V4 is configured to open to apply gas supply pressure from the gas source 170 to the first conduit 131 and the first plurality of apertures 121 in the polishing head 110. The valves V1-V4 are generally operated, so that only one valve fluidly coupled to each conduit 131, 132 is opened at a given time. For example, the first valve V1 and the fourth valve V4 are each fluidly coupled to the first conduit 131 and thus are generally not opened simultaneously.
The plurality of valves further include a first control valve CV1 and a second control valve CV2. The control valves CV1, CV2 are configured to adjust the size of the flow path through the control valves CV1, CV2, so that the control valves CV1, CV2 can precisely control the flow through the control valve CV1, CV2 or pressure in the corresponding conduit 131, 132. The first control valve CV1 is configured to control the flow through the first conduit 131 and/or pressure of the first conduit 131. The second control valve CV2 is configured to control the flow through the second conduit 132 and/or pressure of the second conduit 132.
The polishing system 100 can further include a first sensor S1 and a second sensor S2. In some embodiments, the sensors S1, S2 are each a flowmeter or a pressure sensor. The first sensor S1 can be positioned downstream of the first control valve CV1 on the first conduit 131. The second sensor S2 can be positioned downstream of the second control valve CV2 on the second conduit 132. The sensors S1, S2 can each be connected to the controller 185. The controller 185 can use measurements from the first sensor S1 to control the position of the first control valve CV1 to control the flow through the first conduit 131 or pressure in the first conduit 131. The controller 185 can use measurements from the second sensor S2 to control the position of the second control valve CV2 to control the flow through the second conduit 132 or pressure in the second conduit 132.
The processing system 100 also includes the controller 185 for controlling processes performed by the processing system 100. The controller 185 can be any type of controller used in an industrial setting, such as a programmable logic controller (PLC). The controller 185 includes a processor 187, a memory 186, and input/output (I/O) circuits 188. The controller 185 can further include one or more of the following components (not shown), such as one or more power supplies, clocks, communication components (e.g., network interface card), and user interfaces typically found in controllers for semiconductor equipment.
The memory 186 can include non-transitory memory. The non-transitory memory can be used to store the programs and settings described below. The memory 186 can include one or more readily available types of memory, such as read only memory (ROM) (e.g., electrically erasable programmable read-only memory (EEPROM), flash memory, floppy disk, hard disk, or random access memory (RAM) (e.g., non-volatile random access memory (NVRAM).
The processor 187 is configured to execute various programs stored in the memory 186, such as programs that can be executed to polish the substrate 50 with the polishing system 100. During execution of these programs, the controller 185 can communicate to I/O devices through the I/O circuits 188. For example, during execution of these programs and communication through the I/O circuits 188, the controller 185 can control outputs, such as the position of valves V1-V4, CV1, CV2 to apply vacuum pressure and/or gas supply pressure to the different apertures 121, 122 in the polishing head 110. The memory 186 can further include various operational settings used to control the processing system 100. For example, the settings can include durations for how long the different valves remain open or closed during the polishing processes.
The distribution plate 120 can include the first plurality of apertures 121 and the second plurality of apertures 122. The controller 185 can adjust the positions of the valves V1-V4 to apply vacuum pressure from the vacuum source 160 or gas pressure from the gas source 170 to the apertures 121, 122 during processing. By controlling the position of the valves V1-V4, the gas flow through the first conduit 131 (
The first plurality of apertures 121 are each located a first distance D1 from a center C of the distribution plate 120. The second plurality of apertures 122 are each located a second distance D2 from the center C of the distribution plate 120. Although the first plurality of apertures 121 are shown as having a different size (e.g., diameter) than the second plurality of apertures 122, this is for illustration purposes, and in some embodiments the apertures 121, 122 can have the same size. Additionally, although each of the first plurality of apertures 121 are shown at a same distance D1 from the center C of the distribution plate 120, in some embodiments the first plurality of apertures 121 can be located at numerous distances from the center C of the distribution plate 120, such as two or more or five or more distances from the center C of the distribution plate 120. Similarly, although each of the second plurality of apertures 122 are shown at a same distance D2 from the center C of the distribution plate 120, in some embodiments the second plurality of apertures 122 can be located at numerous distances from the center C of the distribution plate 120, such as two or more or five or more distances from the center C of the distribution plate 120.
The distribution plate 220 includes the first plurality of apertures 121 and the second plurality of apertures 122 that were included in the distribution plate 120. The first plurality of apertures 121 are each positioned at the first distance D1 from the center C of the distribution plate 220. The second plurality of apertures 122 are each positioned at the second distance D2 from the center C of the distribution plate 220.
The distribution plate 220 additionally includes a third plurality of apertures 223 and a fourth plurality of apertures 224. The third plurality of apertures 223 are each located at a third distance D3 from the center of the distribution plate 220. The fourth plurality of apertures 224 are each located at the second distance D2 from the center C of the distribution plate 220. The fourth plurality of apertures 224 are the smaller apertures located at the second distance D2 from the center C of the distribution plate 220. In some embodiments, the polishing system that includes the distribution plate 220 can include separate conduits shut-off valves and control valves for the third plurality of apertures 223 and the fourth plurality of apertures 224, so that independent gas flows and pressures can be provided to the third plurality of apertures 223 and the fourth plurality of apertures 224 in a similar manner as described above for the first plurality of apertures 121 and the second plurality of apertures 122. For example, with this arrangement, four different gas flows and pressures can be applied to the four different sets of apertures 121, 122, 223, 224. The distribution plate 220 in
At block 3002, a new substrate 50 is picked up and retained by the polishing head 110 during a first time period. Vacuum pressure can be applied to the polishing head 110 by opening valves V1 and V3 to assist in picking up and retaining the substrate 50 in the polishing head 110. The vacuum pressure (first pressure) can be applied to the first plurality of apertures 121 and the second plurality of apertures 122 through the respective conduits 131, 132. The second valve V2 and the fourth valve V4 can remain closed during block 3002.
At block 3004, the polishing head 110 is moved to a polishing position over the polishing pad assembly 150 during a second time period occurring after the first time period. For example, the rotatable arm 103 can rotate the polishing head assembly 101 to a position overlying the polishing pad assembly 150. The vertical motor 104 can lower the polishing head 110 onto the polishing pad 60, so that the front side 52 of the substrate 50 contacts the polishing pad 60. The valves V-V4 can remain in the same position during block 3004 as during block 3002.
At block 3006, pressure is applied to the back side 51 of the substrate 50 by providing gas supply pressure through the first plurality of apertures 121 or the second plurality of apertures 122, and the substrate 50 is polished as the substrate 50 is rotated against the polishing pad 60 during the second time period. For example, the fourth valve V4 can open to apply pressure from the gas source 170 through the first plurality of apertures 121, or the second valve V2 can open to apply pressure from the gas source 170 through the second plurality of apertures 122. The third valve V3 can be opened while the first valve V1 and second valve V2 remain closed when the fourth valve V4 is opened during block 3006, so that vacuum pressure is still applied to the polishing head 110. The first valve V1 can be opened while the third valve V3 and fourth valve V4 remain closed when the second valve V2 is opened during block 3006, so that vacuum pressure is still applied to the polishing head 110. The gas supply pressure (second pressure) is greater than the vacuum pressure, such as being greater than atmospheric pressure. The vacuum pressure (third pressure) applied during block 3006 can be the same or different than the vacuum pressure (first pressure) applied during blocks 3002 and 3004.
At block 3006, the rotational motor 106 can be energized to rotate the shaft 108 and polishing head 110, so that the substrate 50 can be polished against the polishing pad 60. Measurements from the sensors S1, S2 can be used by the controller 185 to adjust the position of the control valves CV1, CV2, so that an appropriate amount of pressure is applied to the back side 51 of the substrate 50. The motor 152 of the polishing pad assembly 150 can also be energized to rotate the platen 151 and the polishing pad 60 during the polishing.
At block 3008, the polishing is stopped and the substrate 50 is moved to a transfer position (not shown) during a third time period occurring after the second time period. The rotational motor 106 and the motor 152 can each be de-energized, so that the rotation of the polishing head 110 and substrate 50 is stopped. The first valve V1 and the third valve V3 can each be opened to ensure the substrate 50 is secured in the polishing head 110 by applying the vacuum pressure from the vacuum source 160. The rotatable arm 103 can then move the substrate 50 to a position in which the substrate 50 can be released, such as a position overlying another support (not shown) or a position overlying an end effector of a robot (not shown).
At block 3010, the substrate 50 is released from the polishing head 110 during a fourth time period occurring after the third time period. To release the substrate 50 from the polishing head 110, the second valve V2 and the fourth valve V4 can be opened to apply gas pressure (second pressure) from the gas source 170 to the polishing head 110 while to the first valve V1 and the third valve V3 can be closed to stop the application of vacuum pressure to the polishing head 110.
The method 3000 can then return to block 3002 to pick up a new substrate after which blocks 3004 through 3010 can be completed to perform the polishing process on the new substrate 50.
While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202341087672 | Dec 2023 | IN | national |
