An adaptive centralized transportation system for electroplating.

Abstract

To provide a system and method for plating a workpiece.SOLUTION: In one aspect, an apparatus includes a deposition chamber, a workpiece holder adapted for insertion into and removal from the deposition chamber, a shield with patterns of apertures corresponding to features on the workpiece, a shield holder also adapted for insertion into and removal from the deposition chamber, and a positioning mechanism to position the workpiece in the workpiece holder such that the pattern of apertures on the shield will align with the corresponding features on the workpiece when the workpiece holder and the shield support are inserted into the deposition chamber.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] In one aspect, an apparatus includes a deposition chamber, a workpiece holder adapted for insertion into and removal from the deposition chamber, a shield with a pattern of openings corresponding to features on the workpiece, a shield holder also adapted for insertion into and removal from the deposition chamber, and a positioning mechanism for positioning the workpiece on the workpiece holder such that the pattern of openings in the shield aligns with the corresponding features on the workpiece when the workpiece holder and shield support are inserted into the deposition chamber. [Background technology]

[0002] As critical dimensions of interconnects become tighter, there are several applications in which the spatial and thickness uniformity of features deposited by electrochemical deposition (ECD) is particularly important. The uniformity of such features can be improved through the use of close patterning shields (CPS), which concentrate current in areas of the substrate requiring higher current density.

[0003] Large, thin, rectangular panels of insulating materials are increasingly being used as substrates for advanced packaging applications in electronics. These substrates can be made of organic laminates or glass, assembled using lithographic processes incorporating electroplating. Substrates range in thickness from very thin (100 μm-200 μm) to thick (approximately 2 mm) and are rigid. Other substrates used in advanced packaging include relatively rigid silicon disks and more flexible disks fabricated from molding compound or other insulating materials. The term "workpiece" will be used hereafter to encompass such panels, wafers, and substrates suitable for undergoing ECD processing.

[0004] FIG. 1 schematically illustrates a known electrochemical deposition system 100 for depositing metals at target locations on a workpiece, which system is described in detail in U.S. Patent Application Publication No. 2007 / 0129994. The electrochemical deposition system 100 includes two or more processing modules, including at least one electrochemical deposition module, arranged on a common platform and configured to deposit one or more metals on the workpiece. Each electrochemical deposition (ECD) module includes an anode compartment configured to contain a volume of anolyte fluid, a cathode compartment configured to contain a volume of catholyte fluid, and a membrane separating the anode compartment from the cathode compartment. Alternatively, the ECD module may include a single catholyte compartment for plating metals that does not benefit from separate anolyte and catholyte compartments. The electrochemical deposition system 100 includes a loader module 110 for accepting workpieces entering the electrochemical deposition system 100 through a loading / input stage 112 and loading each accepted workpiece onto a respective workpiece holder 125, such as a flexible panel holder (PH), having a loading port for accepting a set of workpieces.

[0005] The system 100 includes a transport mechanism configured to transport and insert flexible workpieces from the loader module 110 to a given processing module, such as an electrochemical deposition module, via their respective workpiece holders 125. For example, once a workpiece is loaded onto a workpiece holder 125 designated for processing, the workpiece holder 125 can proceed along a processing path 115 (see PH processing path) to be pre-processed, as needed, in one or more pre-processing modules 120, processed in one or more processing modules 130, 132, 134, 136, 138, and post-processed, as needed, in one or more post-processing modules 140. Pre-processing may include, for example, cleaning and / or wetting the workpiece to be processed. Processing may include, for example, depositing a material, such as a metal, on the workpiece, while post-processing may include, for example, rinsing and / or drying the workpiece.

[0006] The load / input port 112 portion of system 100, where unprocessed substrates are loaded onto the workpiece holder, is part of the front end of the system, which may also include a Front Opening Unified Pod (FOUP—not shown). In single-ended systems, unloading also occurs at the front end of the system. ECD system 100 is double-ended, with unloading occurring at the rear end of the system.

[0007] An unloader module 150 removes the flexible workpiece from the workpiece holder and transports the workpiece to an unload port configured to accept a set of workpieces. Once unloaded, the workpiece holder 125 can return along a return path 155 (see PH return path) to the loader module 110 to accept another workpiece. Multiple workpiece holders can be used, with some workpiece holders being held in a storage buffer (not shown).

[0008] The electrochemical deposition system 100 further includes a chemical management system 160 for managing process fluids in one or more process chambers, or modules, 120, 130, 132, 134, 136, 138, or 140. Chemical management may include, but is not limited to, supplying, replenishing, dosing, heating, cooling, circulating, recirculating, storing, monitoring, draining, reducing, etc. The system 100 also includes an electrical management system 170 that can send and receive signals according to computer-coded instructions to control workpiece movement through the electrochemical deposition system 100 or to control chemistries, such as chemical composition, temperature, and flow rates, of the multiple modules 120, 130, 132, 134, 136, 138, and 140. The electrical management system 170 can also be configured to apply an electric current to one or both opposing planar surfaces of a flexible workpiece when held within a given electrochemical deposition module. When doing so, one or both opposing surfaces can be plated with metal and the blind and / or through holes filled with metal.

[0009] Substrates or other workpieces to be processed in such ECD systems can be loaded onto the workpiece holder and transported to the ECD module where processing occurs. FIG. 2 shows a known exemplary workpiece holder 125, consisting of stationary contact seal pieces 121 and 122 that clamp the workpiece W so that the workpiece is held in a first plane. The workpiece holder 125 also includes two fixed legs 111 and 113 attached to a crossbar 107. The exemplary workpiece holder 125 shown in FIG. 2 is described in detail in commonly assigned U.S. Patent Application Publication No. 2009 / 012999, which is incorporated by reference. The workpiece holder 125 is adapted for insertion into and removal from a deposition chamber (such as pre-treatment module 120) while holding a workpiece.

[0010] As understood in the art, dielectric shields with open areas disposed between the anode and cathode or workpiece are used in ECD to globally modify the electric field near the workpiece, thereby modifying the deposition current for uniformity control, e.g., to compensate for thermal curing or other one-dimensional plating effects.

[0011] A proximity patterning shield (CPS), also known as a "current concentration shield," is a dielectric shield that is sufficiently close to the workpiece to enable uniformity control at the length scale of feature patterning. Throughout this document, the terms "proximity patterning shield" and "CPS" are used interchangeably. A proximity patterning shield is similar to a photomask in lithography and contains a pattern of openings specifically designed for use with a specific workpiece pattern. The pattern in the CPS concentrates current where it is needed in the workpiece, for example, in areas where the connection features are most densely packed. The connection features are patterns of wires and pads that repeat at the die scale, so a CPS offers the ability to improve uniformity at the die scale, while in contrast, prior art far uniformity shields (FUS) compensate for current effects at the workpiece scale.

[0012] FIG. 3 schematically illustrates an exemplary CPS 200 in the form of a substantially planar plate having a pattern of apertures formed therein. As shown, the CPS 200 includes a repeating set of aperture patterns 220 for use with a rectangular workpiece. Each aperture pattern 220 in the CPS 200 corresponds to a single die in the workpiece, such that the aperture patterns 220 are arranged in the CPS 200 similar to the array of dies in the workpiece, i.e., the aperture patterns substantially correspond to target locations of features in the workpiece. The proximity patterned shield is held by a shield holder (not shown in FIG. 3) for alignment with the substrate during processing in the ECD module.

[0013] 4 shows an exploded view of an ECD module 503 with a pair of shield holders 320, each for positioning a respective CPS 200 in alignment with a workpiece holder 125, arranged so that each shield holder 320 holds its respective CPS 200 in a second plane substantially parallel to the first plane (of the workpiece). Also shown is an ECD module housing 301 and an anode assembly 302. The anode assembly 302 may consist of a set of individually controllable anodes (not shown) connected to a multi-channel power supply via current connections 303. A second anode assembly 302 may be mounted to the rear of the housing 301 for electroplating on the opposite side of the workpiece W when the workpiece holder 125 is inserted into the ECD module 503. The ECD module 503 also has an actuator (not visible in FIG. 4 ) for setting the distance between each CPS 200 and the workpiece W to properly concentrate the electric field between the anode assembly 302 and the workpiece W. The shield holder 320 is adapted for insertion into and removal from the deposition chamber while holding the CPS 200. Details of the shield holder 320, the ECD module 503, and the operation of the shield holder 320 for positioning adjacent the workpiece holder 125 following insertion into the ECD module 503 are described in commonly-assigned U.S. Patent Application Publication No. 2007 / 0122990, filed by the applicant and incorporated by reference.

[0014] Careful alignment between the proximity patterned shield and the substrate is required during processing. The CPS 200 must be held in place so that its openings 220 align with the corresponding patterns of target locations in the workpiece. Also, there is an optimal distance between the CPS 200 and the workpiece for proper concentration of the electric field.

[0015] 5 schematically illustrates an isometric cross-sectional view of ECD module 503 showing workpiece holder 125 and shield holder 320 after insertion. An actuator 325 is provided on the interior surface of housing 301 and is operable to move cartridge frame 321, translation guides 322, CPS 200, and agitator plate 312 relative to housing 301 to vary the distance between CPS 200 and workpiece W. Actuator 325 can be, for example, pneumatic, mechanical, or electrical.

[0016] FIG. 6 shows the uniformity of plating height of connecting features for CPS 200 as a function of the gap distance between CPS 200 and workpiece W. Three different CPS curves are shown for various shrinkage factor (SF) ratios of the size of the opening 220 to the size of the feature on the workpiece W. For this example, the optimal distance between CPS 200 and workpiece W is approximately 4 mm to 6 mm, depending on the selected shrinkage factor. For an optimal shrinkage factor of 0.7, the optimal distance between CPS 200 and workpiece W is approximately 4 mm. FIG. 6 also shows that uniformity degrades when the distance from CPS 200 to workpiece W is closer or farther than the optimal distance. FIG. 6 also shows equivalent curves for a far uniformity shield (FUS) employing a regularly spaced opening pattern. The curves in Figure 6 show that deposition uniformity for FUS is less sensitive to the distance between the shield and the workpiece than for CPS, which also results in a larger standard deviation in feature height, i.e., poorer uniformity at the die scale. FUS is designed to affect uniformity at the workpiece scale, not the die scale.

[0017] Proximity patterned shields in known ECD tools are stored outside the ECD tool and manually installed. It is preferable to store various shields within the ECD tool so that the desired pattern for a particular workpiece W is available on demand for insertion into the ECD module without the need for manual intervention. Such a tool configuration minimizes tool downtime and reduces the chance for installation errors.

[0018] Proximity patterned shields in ECD chambers must be precisely aligned with respect to the corresponding workpiece pattern in all three dimensions to achieve good deposition uniformity. Shield alignment to the substrate in prior art tools was not precise enough to achieve the required level of uniformity, especially as the critical dimensions of workpiece features became smaller.

[0019] The distance between the proximity patterning shield and the workpiece for optimal current concentration is typically set by the distance between the shield holder and the workpiece holder. For this reason, the distance between the workpiece surface and the CPS may depend on the thickness of the workpiece itself. The distance may also depend on the deflection of the workpiece when mounted on the workpiece holder. Prior art electroplating systems do not take such workpiece-dependent details into account when setting the distance between the concentration shield and the workpiece. [Prior art documents] [Patent documents]

[0020] [Patent Document 1] US Patent Application Publication No. 2017 / 0370017 [Patent Document 2] U.S. Patent No. 10,283,396 [Patent Document 3] U.S. Patent Application No. 16 / 516,714 Summary of the Invention [Problem to be solved by the invention]

[0021] The present invention addresses these concerns by providing an automated system that delivers the proximity patterned shield required for a particular workpiece to the electrodeposition module prior to processing, and then ensures optimal alignment and spacing between the workpiece and the shield during the electrodeposition process. [Means for solving the problem]

[0022] According to a first aspect of the present invention, there is provided an electrochemical deposition system for depositing metal features on a workpiece at respective target locations on the workpiece, comprising: a deposition chamber adapted to receive a plating solution during use; a workpiece holder for holding a workpiece at a first plane, the workpiece holder adapted for insertion into and removal from the deposition chamber while holding the workpiece; a shield comprising a substantially planar plate having a pattern of apertures formed therein, the pattern of apertures substantially corresponding to a target location in use; a shield holder for holding the shield in a second plane substantially parallel to the first plane, the shield holder adapted for insertion into and removal from the deposition chamber while holding the shield; a positioning mechanism for adjusting the position of the workpiece in the first plane, the positioning mechanism operative to position the workpiece such that the target locations are substantially aligned with the pattern of openings when the workpiece holder and the shield holder are inserted into the deposition chamber; An electrochemical deposition system is provided comprising:

[0023] Advantageously, the electrochemical deposition system includes a control system, and the positioning mechanism is configured to adjust the position of the workpiece in the first plane under the control of the control system. Specifically, the positioning mechanism may be configured to adjust the position of the workpiece in the first plane based on data provided by the control system, such as according to a computer model generated by the control system or using measured or otherwise directly obtained data stored in a database of the control system. The data stored in the control system may be based on a model of the physical system or may be based on measured position data. Positioning may be achieved using one or more actuators operating to move the workpiece to achieve such alignment, or by using transport techniques with or without a combination of actuators during insertion of the workpiece into the workpiece holder.

[0024] According to a second aspect of the present invention, there is provided a method for electrochemical deposition of metal features onto a workpiece at respective target locations of the workpiece, comprising the steps of: i) a deposition chamber adapted to receive a plating solution during use; a workpiece holder for holding a workpiece at a first plane, the workpiece holder adapted for insertion into and removal from the deposition chamber; and A shield comprising a substantially planar plate having a pattern of apertures formed therein, the pattern of apertures substantially corresponding to target locations in use. providing a ii) inserting a shield into the deposition chamber; iii) positioning the workpiece relative to the workpiece holder in a first plane; iv) loading the positioned workpiece onto a workpiece holder; v) inserting the loaded workpiece holder into a deposition chamber; vi) depositing a metal feature onto the workpiece; Including, A method is provided in which in step iii), positioning the workpiece relative to the workpiece holder in the first plane substantially aligns the target locations with the pattern of openings when the workpiece holder and shield are inserted into the deposition chamber.

[0025] Other particular aspects and features of the present invention are presented in the accompanying claims.

[0026] The invention will now be described with reference to the accompanying drawings (not to scale): [Brief explanation of the drawings]

[0027] [Figure 1] 1 is a schematic diagram of a known electrochemical deposition system. [Figure 2] 1 is a schematic diagram of a known workpiece holder; [Figure 3] 1 is a schematic top view of a known rectangular proximity patterned shield; [Figure 4] 1 is a schematic isometric exploded view of a known electrochemical plating module together with a known workpiece holder and two shield holders. [Figure 5] 1 is a schematic isometric cross-sectional view of a known electrochemical plating module showing a workpiece holder and a shield holder after insertion. [Figure 6] 4 is a graph of uniformity versus shield-to-workpiece gap for the rectangular, closely positioned shield of FIG. 3 and for the far-field uniformity shield; [Figure 7] 1 is a schematic diagram of an electrochemical deposition system, according to one embodiment of the present invention. [Figure 8] 1 is a schematic diagram of an input / output module, a loader module, and a workpiece holder storage module from above, in accordance with one embodiment of the present invention. [Figure 9]1 is a schematic perspective view of a workpiece loader in one configuration, according to one embodiment of the present invention; [Figure 10] 1 is a schematic perspective view of a workpiece loader in an alternative configuration, according to an embodiment of the present invention; [Figure 11] 1 is a schematic diagram of a top view of a workpiece loader according to one embodiment of the present invention; [Figure 12] 1 is a schematic side view of a workpiece loader in accordance with an embodiment of the present invention; [Figure 13] 2 is a schematic diagram of a top view of a transport arm portion of a workpiece loader in accordance with one embodiment of the present invention; [Figure 14] 1 is a schematic front view of a transport arm portion of a workpiece loader in accordance with one embodiment of the present invention; [Figure 15] 1 is a schematic perspective view from above of a portion of a workpiece loader in accordance with an embodiment of the present invention; [Figure 16] 1 is a schematic perspective view from below of a portion of a workpiece loader in accordance with one embodiment of the present invention; [Figure 17] 1 is a schematic side view of a transporter for transporting a workpiece and a proximity patterned shield holder according to one embodiment of the present invention. [Figure 18] 1 is a schematic front view of a transporter for transporting a workpiece and a proximity patterned shield holder in accordance with one embodiment of the present invention. [Figure 19] 1 is a schematic view from the front of a portion of an enclosed transport for transporting workpieces and proximity patterned shield carriers according to one embodiment of the present invention. [Figure 20] FIG. 1 is a schematic diagram of an electroplating tool storage module for complementing a proximity patterning shield, from above, in accordance with one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0028] For consistency and clarity, like reference numerals are retained for like components throughout the following description.

[0029] 7 schematically illustrates an electroplating tool 500 with an input / output module 510, a loader / unloader module 530, a workpiece holder storage module 580, processing modules 501-505, a proximity patterning shield storage module 590, a transporter support area 570, a maintenance support area 506, an electrical and chemical systems area 507, and a workpiece holder cleaning module 508. Tool 500 is a single-ended tool in that unprocessed substrates are introduced into the tool and processed substrates are removed from the tool at the same input / output front end module 510. While FIG. 7 illustrates five processing modules, tool 500 can have any number of processing modules based on the exact processes being performed, such as the number of different metals being electroplated, the number of pre- and post-electroplating processes required, and the number of dual modules used in parallel to increase tool throughput.

[0030] The workpiece holder storage module 580 is used to store the workpiece holders 125 when they are not in use. A local transport (not shown) transports the workpiece holders 125 from the storage area 580 to the loader / unloader 530 for use. The transporter support area 570 provides mechanical, electrical, and fluid support to two or more transports 571 (see FIG. 17 ) covering the loader / unloader 530, the processing modules 501-505, and the CPS storage area 590. The electrical and chemical systems area 507 houses the power distribution and fluid handling systems for all other modules. The maintenance support area 506 allows support personnel access to the equipment in the electrical and chemical systems area 507 and to all electrical and fluid connections in the processing modules 501-505. The workpiece holder cleaning module 508 contains equipment for cleaning the workpiece holders 125 when they are not being used to process workpieces.

[0031] The process flow for an unprocessed workpiece in tool 500 begins with its transfer by a robot from input / output module 510 to loader / unloader module 530, where the workpiece W is loaded onto workpiece holder 125. The loaded workpiece holder is then transported using a transport mechanism to a series of pre-processing modules 501-502 for wet processing steps such as pre-cleaning, pre-rinsing, and chemical activation. The loaded workpiece holder 125 is then transported to either processing module 503 or 504 for electroplating. After electroplating, the loaded workpiece holder 125 is transported to processing module 505 for further processing steps such as a final rinse and drying. Following the final rinse and drying, the loaded workpiece holder 125 is transported to loader / unloader module 530, where the workpiece W is unloaded from the workpiece holder 125. The processed workpieces W are then transported to the input / output module 510 for storage until all workpieces in the current batch have been processed.

[0032] FIG. 8 schematically illustrates the input / output module 510, the loader module 530, and the workpiece holder storage module 580. Cartesian X, Y, and Z axes are shown, with the Z axis extending vertically upward, while the X and Y axes extend perpendicular to one another in a horizontal plane. For ease of illustration, these axes are also shown in each of FIGS. 9-14. The input / output module 510 includes at least two Front Opening Unified Pods (FOUPs) 511 for storing workpieces, including unprocessed workpieces, such as unprocessed workpieces W and W′, and processed workpieces Wp and Wp′; three FOUPs are shown in FIG. 8. The input / output module 510 also includes a robot 512 configured to travel along a robot rail track 515, the robot 512 including an end effector 514 that can rotate about a vertical axis between two rotational orientations, in a first rotational orientation shown in FIG. 8 , the end effector 514 points to the right, and in a second rotational orientation, the end effector 514 points to the left. The loader module 530 includes a positioning stage 54 0 and , a pivoting rotary opening or "PRO" 550, which is described in more detail below; A positioning mechanism comprising: The workpiece holder storage module 580 includes a carousel 583 adapted for temporary storage of a plurality of workpiece holders 125 in an array, and a local transporter 586 having a pick-up arm 582 that can load workpiece holders 125 from the manual unloading area 585. The local transporter 586 is positioned to transport an empty workpiece holder 125 from the carousel 583 to a position where the transporter 571 can transport the workpiece holder 125 to the loader / unloader module 530 for insertion into the PRO 550.

[0033] The robot 512 is arranged to use the end effector 514 to transfer a single, unprocessed workpiece W from the FOUP 511 to a transfer stage 560 (see FIG. 9 ) located generally below the positioning stage 540, grab the unprocessed workpiece W from the FOUP 511 while in a second rotational orientation and aligned with the intended FOUP 511 through lateral movement along the robot rail track 515, rotate it to a first rotational orientation, align it with the transfer stage 560 through lateral movement along the robot rail track 515, and then place it on the transfer stage 560. Similarly, the robot 512 is arranged to perform a similar operation in reverse to return the processed workpiece Wp from the transfer stage 560 to the FOUP 511 after processing. The end effector 514 may include, for example, a lightweight, rigid material such as a carbon fiber composite. As shown, the end effector 514 may include mechanical features for gripping an edge of the workpiece W. Alternatively, the end effector 514 may include other means, such as a vacuum cup or Bernoulli gas jet, to grasp the back side of the workpiece W and hold it flat for subsequent loading operations. Alternatively, the robot 512 may include two end effectors 514 to maximize system throughput when exchanging an unprocessed workpiece for a processed workpiece via so-called "give and get" maneuvers, and may be coupled to multiple linkages 513 to allow sufficient reach to place the workpiece W on the transfer stage 560.

[0034] FIG. 9 schematically illustrates a perspective view of workpiece loader 535, including PRO 550, positioning stage 540, and workpiece transfer stage 560, all mounted on support frame 539. PRO 550 is disposed in a horizontal position and is rotated about axis 551 by pivot arm 552 when actuated by motor drive 553. Two slots 554 and 554' are formed in the upper end of PRO 550, each having an edge guide 555 and configured to receive a respective workpiece holder 125 (not shown in FIG. 9). With PRO 550 in this horizontal position, workpiece holder 125 can be inserted into slots 554 and 554' from above by transport 571. Workpiece transfer stage 560 includes upper transfer arm 561 and lower transfer arm 562. Upper transport arm 561 is shown carrying an unprocessed workpiece W prior to alignment in positioning stage 540. Transport stage 560 is shown in a lowered position, which is used for the transfer of workpieces between input / output module 510 and loader / unloader module 530 via upper transport arm 561.

[0035] Figure 10 shows a schematic perspective view of workpiece loader 535 in a second configuration in which PRO 550 is arranged in a vertical position, i.e., rotated 90° about axis 551 compared to the position shown in Figure 9. Transport stage 560 is slightly elevated compared to Figure 9 and is in a position used for the transfer of workpieces between input / output module 510 and loader / unloader module 530 via lower transport arm 562. Workpiece holder 125 in slot 554 (not visible in Figure 10), which in this position is located below slot 554', is now accessible for the exchange of a processed workpiece with an unprocessed workpiece using transport arms 561 and 562. During transfer of the processed workpiece from slot 554 to input / output stage 510 by linkage 513, PRO 550 is rotated 180° to an inverted vertical position (not shown) to make the other slot 554' accessible for exchanging the processed workpiece for an unprocessed workpiece. This step sequence is described in more detail below.

[0036] FIG. 11 shows workpiece loader 535 from above, with PRO 550 in a first, horizontal configuration. PRO 550 is shown with workpiece holder 125 inserted into slot 554, which is positioned to the right of slot 554′ in this position as shown. Workpiece holder 125 has a pick-up feature 556 that mates with a corresponding pick-up feature (not shown) on transporter 571 to lift workpiece holder 125 (when loaded with workpiece W) from slot 554 and transport it to any of modules 501-505 as needed. FIG. 11 also shows robot 512 with workpiece W held by end effector 514 positioned on transport arm 561 below positioning stage 540. Following placement on positioning stage 540 by transfer arm 561, workpiece W can be precisely positioned relative to positioning frame 541 by appropriate actuation of positioning actuators 546 attached to positioning frame 541. Alternatively, actuators 546 may position workpiece W parallel to the Y axis, and end effector 514 may position workpiece W parallel to the X axis relative to workpiece holder 125 during insertion. Alternatively, end effector 514 may position workpiece W parallel to both the X and Y axes during insertion into workpiece holder 125.

[0037] FIG. 12 shows a schematic side view of the workpiece loader 535 with the workpiece holder 125 inserted into the slot 554 and the PRO 550 in its second configuration, i.e., vertical orientation. An elongated actuating member 567 is attached to the PRO 550 and includes a bladder opener 566 for effecting the opening of the contact seal segments 121, 122 (see FIG. 5) while the workpiece holder 125 is inserted into the slot 554. Suitable actuating members 567 and bladder openers 566 are described in detail in commonly assigned U.S. Patent No. 6,223,999, which is incorporated by reference. The PRO 550 requires one bladder opener for each contact seal segment. A workpiece holder 125 adapted to hold one workpiece includes two contact seal segments and therefore requires two openers 566, while a workpiece holder 125 adapted to hold two workpieces includes four contact seal segments and therefore requires four openers 566.

[0038] Each bladder opener 566 is inflatable to allow both the removal of a processed workpiece by the lower transport arm 562 and the loading of an unprocessed workpiece W by the upper transport arm 561. As shown, the transport stage 560 includes an upper transport arm 561, which is shown supporting a workpiece W thereon, a lower transport arm 562, a vertical drive 664, and a horizontal drive 665. The vertical drive 664 and the horizontal drive 665 are both motorized and operate to vertically and horizontally position the transport arms 561 and 562 relative to the positioning stage 540 and the workpiece holder 125, respectively. Each of the upper transport arm 561 and the lower transport arm 562 is operable to "grab" a workpiece thereon, i.e., to provide a suitable, flat support for the workpiece. Such gripping may be switchable, for example, if a vacuum chuck is used, a vacuum supply (not shown) may be switchably connected to each transport arm 561, 562, along with a connection to a positive pressure source (not shown) for optionally floating the workpiece in inert gas or compressed dry air during positioning.

[0039] 13 shows, from above, a schematic view of an upper transport arm 561 for use in a transport stage 560 for loading a workpiece W onto the holder 125 in the PRO 550. The transport arms 561 and 562 have similar features for gripping a workpiece as the end effectors 514, i.e., the upper transport arm 561 and the lower transport arm 562 may include mechanical features for gripping the edges of the workpiece W, or alternatively, may include vacuum or suction cups or Bernoulli gas jets for gripping the back side of the workpiece W and holding it flat for a subsequent loading operation, specifically for loading the workpiece W onto the workpiece holder 125.

[0040] 13 , the upper transfer arm 561 may include a frame 563, suction cups 564, and a vacuum connection 565. The frame 563 may be fabricated, for example, from aluminum, carbon composite, or other rigid, lightweight material and, as shown, includes first and second parallel outer arms 569 and an inner arm 568 disposed parallel to the outer arms 569, the inner arm 568 being shorter in length than the first and second outer arms 569. The suction cups 564 may have multiple folds and sufficient compliance to allow the vacuum to grip a workpiece W with significant deflection. The upper transfer arm 561 may also include a separately switchable vacuum connection (not shown) that maintains a vacuum at the outer arm 569 while either no pressure or a slight positive pressure is present at the inner arm 568.

[0041] 14 shows a schematic side cross-sectional view of an upper transport arm 561 including a frame 563, suction cups 564, and a vacuum fitting 565 with a workpiece W positioned thereon. The vacuum fitting 565 can be switchably connected to a vacuum supply (not shown) for vacuum gripping the workpiece W via the suction cups 564. The fitting 565 can also be switchably connected to a positive gas supply (not shown) for suspending the workpiece W on a gas cushion during positioning. A cavity 589 is provided in the frame 563 to provide fluid communication between the vacuum fitting 565 and the suction cups 564.

[0042] 15 and 16 show, in perspective views, generally from above and below, respectively, positioning stage 540, including its positioning frame 541 in which workpiece W is positioned while supported by upper transport arm 561 (not shown). Positioning stage 540 is supported by supports 545. A sensor crossbar 544 extends across positioning frame 541 and carries a plurality of ultrasonic positioning sensors 543. A charge-coupled device (CCD) positioning camera 542 is also mounted on positioning frame 541.

[0043] The CCD positioning camera 542 operates to control the operation of the positioning actuator 546, which in turn adjusts the positioning of the workpiece W within the positioning frame 541, based on observation of fiducial marks (not shown) on the workpiece W. The ultrasonic positioning sensors 543 are preferably capable of determining the distance between each sensor 543 and the workpiece W with a resolution of at least 0.3 mm. Multiple ultrasonic sensors 543 mounted on the positioning frame 541 can be used to ensure that the workpiece W is flat and well-held by the upper transport arm 561 prior to loading of the workpiece W into the PRO 550 (see, e.g., FIG. 12 ). As shown, two ultrasonic sensors 543 are supported by a sensor crossbar 544 and can be used to measure the degree of deflection of the workpiece W. This information can be used to determine the appropriate position of the CPS shield 200 relative to the surface of the (potentially deflecting) workpiece W in the ECD module 503. The deflection of the workpiece can be measured while the workpiece is parked for gripping by the transport arm 561. The deflection of the workpiece can be measured in a similar manner to the workpiece in the holder 125, for example, by simply gripping the workpiece W using the suction cups 564 on the outer arms 569 (see FIG. 13) while maintaining zero or a slight positive pressure on the suction cups 564 on the central arms 568.

[0044] Various commercially available ultrasonic sensors may be suitable for use as sensor 543, including, by way of example only, the "UNDK" series ultrasonic distance measurement sensors available from Baumer Ltd. of Southington, Connecticut. CCD positioning camera 542 is capable of locating fiducial marks and panel edge positions with a resolution of 50 μm or better. CCD cameras with the required resolution include, by way of example only, "FLIR" high performance cameras available from Edmunds Optics of Barrington, New Jersey. Positioning actuator 546 is preferably a linear stepper motor with a positioning accuracy of 50 μm or better, such as, by way of example only, the high performance "G series" actuators available from Hayden Kerk / Ametek of Waterbury, Connecticut.

[0045] 17 shows a schematic side view of a transport 571 for transporting one workpiece holder 125 at a time from the loader / unloader module 530 to the processing modules 501-505, and for transporting a shield holder 320 from the shield holder storage module 590 to the processing modules 501-505. The transport 571 includes a wheeled buggy 575, a transport vertical positioning device 573, and an enclosure transport 572.

[0046] Wheeled buggy 575 rides on transport rails 574 that extend the length of transport support area 570 and is driven along transport rails 574 by motor assemblies 579. Transport rails 574 can support several transports 571 to allow transport of several workpiece holders 125 at a time for increased throughput or to allow changing of shield holders 320 in ECD module 503 while simultaneously processing workpieces in processing modules 501, 502, 504, and / or 505.

[0047] Transport vertical positioning device 573 includes a coiled belt spool 577 driven by a vertical wrap motor 576. Enveloping transport 572 includes a drop block 578 connected to coiled belt spool 577 by a metal lift belt 581. Drop block 578 includes a lift clamp 588 that, when actuated, grips pick-up feature 556 of workpiece holder 125.

[0048] 18 schematically illustrates the transport 571 from a front view. A connecting spool 583 attaches the transport vertical positioning device 573 to the enclosing transport 572 and provides conduits for electrical cables and gas piping, for example, for purging the enclosing transport 572 with nitrogen gas during transport. The enclosing transport 572 includes guide features 585 for guiding the drop block 578 during drop and pick-up operations, and a bottom cover 583 that can be actuated to close during transport and open during drop and pick-up. The enclosing transport 572 can include an RFID reader 584 for identifying the workpiece holders 125 (typically including RFID tags) and / or the shield holders 320 including RFID tags when removed from the process modules 501-505 and CPS storage area 590.

[0049] 19 shows a schematic of the enclosure transport 572 from the front. Lift clamps 588 of drop block 578 grip lift features 556 of shield holder 320 for transport from shield holder storage module 590 to ECD module 503.

[0050] 20 shows a schematic top view of a shield storage module 590 for storing multiple shield holders 320, each holding a respective CPS 200, when not in use in a processing module 501-505. The shield storage module 590 includes multiple storage bays 594 with features (not shown) for physically supporting and positioning each shield holder 320. The shield storage module 590 also includes an ejection platform 593 for manually loading and unloading shield holders 320 from the shield storage module 590, and an overhead transport 597 supported on transport rails 596 for transporting the shield holders 320 from the ejection platform 593 to the target storage bays 594. The shield storage module 590 also includes a transport delivery platform 591 that interfaces with an overhead transport 597 to transport the shield holder 320 to and from the processing modules 501-505. During pick-up of the shield holder 320 by the overhead transport 597, the identity of the shield holder 320 holding the CPS 200 can be verified by reading an RFID tag 598 located within the shield holder 320 using an RFID reader.

[0051] The system also includes a control system (not explicitly shown) for controlling the apparatus. The control system may, for example, include a suitably programmed computer, computing means, or similar processing device (whether embodied in hardware, software, and / or running a cloud-based application). The control system may be located at or within the main apparatus footprint, or remotely. As noted above, the positioning mechanism is configured to adjust the position of the workpiece under the control of the control system. Specifically, the positioning mechanism is configured to adjust the position of the workpiece based on data provided by the control system, such as, for example, according to a computer model generated by the control system or using measured or otherwise directly obtained data stored in the control system's database. Such data relates to the physical location of the shield in the process chamber, including the apparatus location, and the target location pattern of the positioned workpiece, enabling a match between the target location pattern and the opening pattern of the shield to ensure alignment between them once the workpiece holder and the shield holder are inserted into the deposition chamber. For example, such a database may hold data about target locations on the workpiece obtained from Gerber or equivalent data associated with the workpiece, or equivalent data obtained from direct measurements of marked target locations on the workpiece. The database may also include data about the optimal focal length between the workpiece and the shield, various shield configurations, and data about the relationship between agitation speed, plating speed, plating uniformity, and workpiece deflection.

[0052] Processing Steps Specifically, for workpieces where spatial and thickness uniformity are particularly important, the main processing steps for a method for improving the uniformity of features deposited on a workpiece by electroplating are presented herein.

[0053] Two sets of processing steps are listed, one set for CPS 200 and a second set for workpieces W and W′. These two sets of processing steps may be asynchronous, that is, delivery of workpiece W to FOUP 511 may occur before, during, or after preparation of CPS 200. Similarly, transfer of workpiece W to transfer stage 560 may occur before, during, or after selection and transport of shield 200, as long as CPS 200 is present in ECD module 503 during ECD processing of workpiece 125.

[0054] The following steps describe operation for a workpiece holder 125 that is capable of holding two workpieces W and W′ on a workpiece holder 125 with four contact seal pieces. For a workpiece holder 125 configured to hold only a single workpiece W, workpiece processing step 5 is not applicable.

[0055] CPS Processing Steps 1. Prepare tool with proximity patterned shields 200: At least two CPSs 200, which may contain various aperture patterns, are loaded into their associated shield holders 320 using an ejection platform 593 and overhead transport 597 and manually stored in their respective storage bays 594.

[0056] 2. Select a CPS 200 from the list of available CPSs in the shield storage module 590: That particular shield is selected because the repeating set of aperture patterns 220 in the particular CPS 200 corresponds to the target location of the desired plating feature on the workpiece W.

[0057] 3. Transporting CPS 200 from Shield Storage Module 590 to ECD Processing Module 503: The shield holder 320 with its CPS 200 is transported from its storage bay 594 to the transport delivery platform 591 using an overhead transport 597. The identity of the CPS 200 can be confirmed by reading the RFID tag 598. The shield holder 320 with its CPS 200 is transported to the ECD processing module 503 using the transport 571. The shield holder 320 is inserted into the processing module 503 using a drop block 578. This step may be repeated for a second CPS for plating a double-sided workpiece or for sequential plating of one side of two workpieces.

[0058] 4. Return CPS 200 from ECD processing module 503 to shield storage module 590: When the operator indicates that a different patterned shield is needed in ECD module 503, CPS 200 is transferred to storage module 590. CPS processing steps 1-3 are then repeated for the CPS 200 with a different aperture pattern 220.

[0059] Workpiece Processing Steps 1. Load Unprocessed Workpiece W: Robot 512 uses end effector 514 to transfer unprocessed workpiece W from FOUP 511 to upper transfer arm 561 of transfer stage 560. Vacuum is applied to suction cup 564 and workpiece W is raised to a position within positioning stage 540 in vertical alignment with positioning actuator 546, to a height slightly below frame 541.

[0060] 2. Position workpiece W on workpiece holder 125: The vacuum to port 565 of upper transport arm 561 is turned off and a slight positive pressure is applied, allowing workpiece W to float freely in suction cups 564 of transport arm 561. Using images from CCD positioning camera 542 to monitor the reference image on workpiece W, positioning actuator 546 positions workpiece W on upper transport arm 561 so that target locations of features on workpiece W will align with corresponding openings in shield 200 after step 7 below. Data for determining the appropriate position can be provided by the control system based on a computer model of the system, or can be determined experimentally and stored in a database. Following positioning of workpiece W, suction cups 564 on outer arms 569 of upper transport arm 561 are activated to clamp workpiece W on upper transport arm 561. The deflection of the workpiece W may be measured using the ultrasonic sensor 543 and stored in a database before applying a vacuum to the suction cups 564 of the central arm 568 .

[0061] 3. The PRO 500 is pivoted to a horizontal position to allow access to the workpiece holder 125. Vacuum is applied to port 565 of the lower transfer arm 562 to grasp the workpiece. The bladder opener 566 is actuated to open the contact seal pieces 121 and 122. The lower transfer arm 562 removes the workpiece Wp from the workpiece holder 125.

[0062] 4. Loading unprocessed workpiece W onto workpiece holder 125: Bladder opener 566 in slot 554 is actuated to inflate, opening contact seal segments 121, 122 on workpiece holder 125. Workpiece W is then inserted into the opened workpiece holder 125 using upper transport arm 561. Bladder opener 566 is then deactivated before removing the vacuum clamp of workpiece W from upper transport arm 561, thereby ensuring that workpiece W is properly positioned when inserted into ECD module 503.

[0063] 5. Repeat Positioning and Loading of Unprocessed Workpiece W′: Robot 512 uses end effector 514 to transfer processed workpiece Wp from lower transport arm 562 to FOUP 511. Workpiece steps 1-4 are then repeated for unprocessed workpiece W′ for loading into the second position of workpiece holder 125.

[0064] 6. Load second workpiece holder 125': PRO 550 is rotated 180 degrees so that second slot 544' of PRO 550 is accessible for removal by upper transport arm 561 and lower transport arm 562. Workpiece steps 1-5 are repeated to remove processed workpieces Wp" and Wp'" and load unprocessed workpieces W" and W'".

[0065] 7. Transport workpiece holders 125 and 125′ for pre-processing: PRO 550 is pivoted to its second horizontal configuration and transporter 571 is operated to pick up and transport the first workpiece holder 125 with its unprocessed workpieces W and W′ to pre-processing module 501. Transporter 571 then transports the second workpiece holder 125′ to pre-processing module 502.

[0066] 8. Transporting workpiece holders 125 and 125′ for ECD processing: Transporter 571 transports pre-processed workpieces W and W′ to ECD module 503. Workpiece holder 125 is then inserted into ECD processing module 503 using drop block 578. Transporter 571 then transports pre-processed workpieces W″ and W′″ to ECD processing module 504.

[0067] 9. Adjust the gap between CPS 200 and workpiece W: Using actuator 325, the gap between CPS 200 and workpiece W in workpiece holder 125 in ECD module 503 can be set to a value that optimizes feature uniformity in workpiece W while keeping CPS 200 and workpiece W parallel. The optimal distance can be determined by computer modeling of the focal length of CPS 200 or by experimental methods. The optimal distance may depend on the thickness of workpiece W and the deflection of workpiece W as measured in step 2 above. The gaps for workpieces W′, W″, and W′″ can be set similarly.

[0068] 10. Deposit metal on workpieces: The features in workpieces W, W', W", and W''' are filled with metal using electrochemical deposition.

[0069] 11. Complete post-processing: The workpiece holders 125 and 125' are transported to the post-processing module 505 for rinsing and drying operations.

[0070] 12. Remove Processed Workpieces: PRO 550 is pivoted to a vertical orientation. Workpiece holders 125 and 125′ are transported to loader / unloader section 530 and inserted into slots 554 and 554′. PRO 550 is pivoted to a horizontal orientation to allow removal of the currently processed workpieces W, W′, W″, and W′″ as described in Workpiece Step 3. [Explanation of symbols]

[0071] 120 Pre-processing module, module 121, 122 Fixed contact seal pieces 125, 125' Workpiece holder 130, 132, 134, 136, 138 Processing module, module 140 Post-processing module, module 200 Proximity Patterned Shield, CPS 320 Shield holder 500 Electroplating Tools 501, 502 Pre-processing module 503, 504 ECD processing module 505 Post-processing Module 506 Maintenance Support Area 507 Electrical and Chemical Systems 508 Workpiece holder cleaning module 510 Input / Output Module, Input / Output Front End Module, Input / Output Stage 511 Front Opening Unified Pod, FOUP 512 Robot 513 Link Mechanism 514 End Effector 515 Robot Rail Track 530 Loader / Unloader, Loader / Unloader Module, Loader Module 535 Workpiece Loader, Loader 539 Support Frame 540 Positioning Stage 541 Positioning Frame 542 Charge-Coupled Device (CCD) Positioning Camera 543 Ultrasonic positioning sensor, sensor, ultrasonic sensor 544 Sensor Crossbar 544' Second Slot 545 Support 546 Positioning Actuator, Actuator 550 Pivot Rotary Release Tool, PRO 551 shaft 552 pivot arm 553 Motor drive unit 554, 554' slot 555 Edge guide 556 Pickup feature, lift feature 560 Workpiece Transfer Stage, Transfer Stage 561 Upper transfer arm, transfer arm 562 Lower transfer arm, transfer arm 563 frames 564 Suction Cup 565 Vacuum fittings, connectors, ports 566 Bladder release tool, release tool 567 Actuating member 568 inner arm, central arm 569 Outer Arm 570 Transport aircraft support area 571 Transport aircraft 572 Siege Transport 573 Transport aircraft vertical positioning device 574 Transport Rail 575 Wheeled Buggy 576 Vertical Winding Motor 577 Coiled Belt Spool 578 Falling Block 579 Motor Assembly 580 Workpiece holder storage module, storage area 582 Pick-up arm 583 Rotating shelf, connecting spool, bottom cover 584 RFID reader 585 Manual Eject Area, Guidance Features 586 Local Transport 588 Lifting Clamp 590 Proximity patterned shield storage module, shield holder storage module, shield storage module, CPS storage area 591 Transport Aircraft Delivery Platform 593 Ejection Platform 594 Target Storage Bay, Storage Bay 596 Transport Rail 597 Overhead transport aircraft 598 RFID tags 664 Vertical drive unit 665 Horizontal drive unit W, W', W", W''' Untreated workpiece Wp, Wp', Wp", Wp''' Processed workpieces

Claims

1. 1. An electrochemical deposition system for depositing metal features on a workpiece at respective target locations on the workpiece, comprising: a deposition chamber adapted to receive a plating solution during use; a workpiece holder for holding a workpiece at a first plane, the workpiece holder adapted for insertion into and removal from the deposition chamber while holding the workpiece; a shield comprising a substantially planar plate having a pattern of apertures formed therein, said pattern of apertures substantially corresponding to said target locations in use; a shield holder for holding the shield in a second plane substantially parallel to the first plane, the shield holder adapted for insertion into and removal from the deposition chamber while holding the shield; a positioning mechanism including a pivotable rotary opener (PRO) movable to a plurality of different orientations each aligned with a respective plane, the PRO being configured and operative to receive the workpiece holder while in a first orientation of the plurality of different orientations aligned with a first plane; the positioning mechanism is configured to receive a workpiece from storage and is operable by an actuator to align the workpiece, such that when the workpiece holder and the shield holder are inserted into the deposition chamber, the target location is substantially aligned with the pattern of openings in the shield while the shield is held by the shield holder during deposition of metal at the target location in the deposition chamber, and the PRO is movable to a second orientation of the plurality of different orientations aligned with a second plane different from the first plane to receive the aligned workpiece within the workpiece holder within the PRO; a transporter operative to transport the workpiece holder holding the aligned workpiece from the PRO to the deposition chamber; 1. An electrochemical deposition system comprising:

2. The system of claim 1 , wherein the electrochemical deposition system further comprises an additional actuator operable to change the relative distance between the workpiece holder and the shield holder.

3. 3. The system of claim 2, wherein the additional actuator is operable to change the relative distance between the workpiece holder and the shield holder in a direction perpendicular to the first plane and the second plane of the shield holder while the workpiece holder and the shield holder are positioned in the deposition chamber.

4. The system of claim 2 , wherein the positioning mechanism comprises an optical camera capable of imaging workpiece features.

5. The system of claim 1 , wherein at least one of the actuators is operable to change the relative position of the workpiece and the workpiece holder in a plane parallel to the workpiece.

6. The system of claim 1 , wherein the positioning mechanism comprises a distance sensor capable of measuring deflection of the workpiece.

7. The system of claim 1 , wherein the positioning mechanism comprises a transport arm positioned to receive the workpiece and deliver the workpiece to the workpiece holder.

8. The system of claim 7 , wherein the actuator is configured to adjust the relative position of the workpiece with respect to the transport arm prior to inserting the workpiece into the workpiece holder.

9. The system described in claim 1, wherein the first plane of the positioning mechanism is a vertical plane and the second plane of the positioning mechanism is a horizontal plane.

10. 10. The system of claim 1, wherein the transporter is operable to transport the workpiece holder and the aligned workpiece held by the workpiece holder to a pre-processing module, and to transport the workpiece holder and the aligned workpiece held by the workpiece holder from the pre-processing module to the deposition chamber.

11. 10. The system of claim 1, wherein the electrochemical deposition system includes a control system, and the positioning mechanism is configured to adjust the position of the workpiece relative to the workpiece holder in the second plane under the control of the control system.

12. 12. The system of claim 11, wherein the positioning system comprises at least one actuator configured to move the workpiece in the second plane relative to the workpiece holder based on a computer model or data stored in a database.

13. 1. A method for electrochemical deposition of metal features onto a workpiece at respective target locations of the workpiece, comprising: i) a workpiece onto which the metal features are to be deposited at respective target locations; a deposition chamber adapted to receive a plating solution during use; a workpiece holder for holding a workpiece at a first plane, the workpiece holder adapted for insertion into and removal from the deposition chamber while holding the workpiece; a shield comprising a substantially planar plate having a pattern of apertures formed therein, the pattern of apertures substantially corresponding to the target location in use; and a positioning mechanism including a pivotable rotary opener (PRO) movable to a plurality of different orientations each aligned with a respective plane, the PRO configured and operative to receive the workpiece holder while in a first orientation of the plurality of different orientations aligned with a first plane; providing a ii) inserting the shield into the deposition chamber; iii) receiving the workpiece holder by the PRO while the PRO is in the first orientation of the plurality of different orientations aligned with the first plane; iv) positioning the workpiece with the positioning mechanism relative to the workpiece holder such that the target locations are substantially aligned with the pattern of openings in the shield while the shield is held by the shield holder during deposition of metal at the target locations in the deposition chamber; v) moving the PRO to a second orientation of the plurality of different orientations aligned with a second plane different from the first plane; vi) loading the positioned workpiece into the workpiece holder within the PRO; vii) transporting the workpiece holder holding the aligned workpiece from the PRO to the deposition chamber; viii) inserting the loaded workpiece holder into the deposition chamber; ix) depositing a metal feature onto said workpiece; A method comprising:

14. The method of claim 13 , wherein step i) includes providing at least one additional shield.

15. The method of claim 14 , wherein the shield and the at least one additional shield are provided in a shield storage area.

16. 16. The method of claim 15, wherein step ii) initially comprises selecting a shield from the shield storage area for insertion into the deposition chamber.

17. The method of claim 16 , wherein in step ii) the shields are transported from the shield storage area to the deposition chamber.

18. 14. The method of claim 13, wherein step ii) comprises inserting the shield into a shield holder that holds the shield in a second plane that is substantially parallel to the first plane of the workpiece holder.

19. 20. The method of claim 18, wherein step ii) further comprises inserting the shield into the deposition chamber while the shield is held by the shield holder.

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