JP2006511717A5 - - Google Patents

Description

Multi-chemical electrochemical processing system Background of the Invention

Field of Invention

  [0001] Embodiments of the present invention generally relate to electrochemical processing systems and methods for electrochemically depositing a conductive material on a substrate.

Explanation of related technology

  [0002] Metallization of sub-quarter micron features is a fundamental technique for current and future generation integrated circuit manufacturing processes. More particularly, in devices such as very large scale integrated devices, i.e. devices having integrated circuits with more than one million logic gates, the multilevel interconnects present in the center of these devices generally have aspect ratios. High, i.e., about 4: 1 or greater interconnect features are filled with a conductive material such as copper or aluminum. Traditionally, deposition techniques such as chemical vapor deposition (CVD) and physical vapor deposition (PVD) have been used to fill these interconnect features. However, as interconnect sizes decrease and aspect ratios increase, it becomes increasingly difficult to fill interconnect features without voids with conventional metallization techniques. Therefore, plating techniques, namely electrochemical plating (ECP) and electroless plating, have emerged as promising processes for void-free filling of sub-quarter micron high aspect ratio interconnect features in integrated circuit manufacturing processes. did.

  [0003] For example, in an ECP process, a sub-quarter micron high aspect ratio feature formed on the surface of a substrate (or a layer deposited thereon) is efficiently filled with a conductive material such as copper. can do. The ECP plating process is generally a two-step process, i.e., first forming a seed layer over the surface features of the substrate, then exposing the surface features of the substrate to the electrolytic solution, An electrical bias is applied between the copper anode positioned in the solution. The electrolytic solution generally includes ions to be plated on the surface of the substrate, and therefore, when an electrical bias is applied, these ions are forced to be plated from the electrolytic solution onto the biased seed layer, Thus, a layer of ions can be deposited on the substrate surface to fill the feature.

[0004] It is desirable to fill surface features such as vias and trenches as quickly as possible without creating defects in the fill layer to facilitate throughput of the semiconductor device manufacturing process. However, plating compositions that generally increase feature fill rates often form films with poor flatness and high defect ratios. For example, the configured composite to quickly deposit the material on the features of the close spacing generally stacked thickness from upper corner of the feature, finally, across the top of the feature merging And create a high spot against the surrounding film. Further, if material builds up too quickly from the top corner of the feature, the feature opening may close and voids may be formed. Conversely, composites that promote planarization and substantially defect-free films generally have slower plating rates and leave the top of the feature open, but inherently slower throughput. Therefore, conventional electrochemical plating composites are generally configured to balance or compromise feature filling performance with defect and planarization characteristics. More particularly, composite in the plating cell is generally composed while minimizing defects, to provide the feature filling rate that is acceptable for obtaining a throughput easily. However, since composites must balance the need for two separate processes with different goals, certain properties in each process must be sacrificed in nature, ie increased throughput generally results in defect ratios. At the expense of

[0005] However, it is desirable to provide a plating system that can provide multiple composite capabilities so that the effective properties of multiple composites can be combined into a single plating process. In addition to being applied to feature filling and bulk filling processes, the system with multi- composite capability is in addition to various other plating processes that conventionally require balancing the plating characteristics of a single composite plating process. Also effective against. For example, a multi- composite plating system can use a first plating composition to facilitate adhesion to the barrier layer (a general slow plating process) and then use a second composite. Since the features can be filled by plating on the top layer of the barrier layer without the difficulty of adhesion, direct plating on the barrier layer is facilitated. Furthermore, the multi- composite system can use the first chemical to plate the alloy layer, and then use the second composite to use a different layer or another alloy over the already deposited layer. It is also useful for alloy plating processes where layers can be plated. Furthermore, the multi-composition process, using a first composite configured to plating the first layer with minimal defects (commonly at a lower rate), then the minimum so as to optimize throughput By using a second composite configured to plate the second layer over the first layer with defects, it can be used to substantially improve the defect ratio in the semiconductor substrate plating process.

[0006] Therefore, there is a need for an improved electrochemical plating system that is configured to provide multiple composites for a single electrochemical plating process.

Summary of the Invention

[0007] Embodiments of the present invention generally provide an electrochemical processing system configured to provide multiple composites for a single plating process. These multiple composites include direct plating on the barrier layer, alloy plating, plating on thin seed layers, optimal feature and bulk fill plating, plating with minimal defects, and / or multiple composites. The product can be used to carry out other plating processes, which can take advantage of the properties of each composite . The multiple composites are generally provided in separate electrochemical processing cells positioned in an integral electrochemical plating system.

[0008] Embodiments of the present invention further communicate with a system platform having a plurality of processing cells positioned therein, a robot positioned to transfer a substrate between the plurality of processing cells, and the system platform. An electrochemical processing system is provided that includes a positioned factory interface configured to supply a substrate to a system platform for processing. The system further comprises a fluid delivery system in fluid communication with each of the plurality of processing cells, the fluid delivery system being configured to provide a plurality of composites to each of the plurality of processing cells.

[0009] Embodiments of the invention can further provide an electrochemical processing system. The processing system includes a processing system base having a plurality of processing cell locations, at least two electrochemical plating cells positioned at two of the processing cell locations, and at least one spin rinse positioned at one of the processing cell locations. A drying cell and at least one substrate bevel cleaning cell positioned at another one of the processing cell locations may be included. The processing system can further include a multi- composite plating solution delivery system in fluid communication with at least two electrochemical processing cells. The multi- composite plating solution delivery system generally includes a metering pump, a plurality of plating solution addition containers in fluid communication with the metering pump, at least one first virgin electrolyte solution container in fluid communication with the metering pump, and a metering pump. A plating solution distribution manifold is provided in fluid communication with the pump outlet and in selective and individual fluid communication with each of the at least two electrochemical plating cells.

[0010] Embodiments of the present invention further deliver a plurality of electrochemical processing cells positioned in the system base and a plurality of different electrochemical plating compositions to each of the plurality of electrochemical processing cells. And an electrochemical processing system having the means.

[0011] Embodiments of the invention can further provide a method for electrochemically plating at least one layer on a semiconductor substrate. The method generally includes positioning a substrate in a first electrochemical plating cell on an integral plating system platform for a first plating operation, and on an integral plating system platform for a second plating operation. comprises positioning a substrate in a second plating cell, a first step of supplying electrochemical plating composition in a first plating cell in the fluid delivery system of a multiple synthesizer was first in a multi-compound fluid delivery system Supplying a second electrochemical plating composition to the two plating cells, wherein the first and second compositions are different.

  [0012] In order that the foregoing features of the invention may be understood in detail, a more particular description of the invention briefly summarized above may be had by reference to the embodiments illustrated in the accompanying drawings. . However, it should be noted that the accompanying drawings only show typical embodiments of the present invention, and therefore do not limit the scope of the present invention, and that the present invention is also susceptible to other equally effective embodiments. I want to be.

Detailed Description of the Preferred Embodiment

[0019] Embodiments of the present invention generally provide an electrochemical plating system configured to plate a conductive material, such as a metal, on a semiconductor substrate using a plurality of composites . Implementing multiple composites on a single plating platform allows optimization of multiple process steps, which results in improved film quality and improved system throughput. Embodiments of the present invention include direct plating on barrier layers, alloy plating, alloy plating combined with conventional metal plating, plating on thin seed layers, optimal feature fill and bulk fill plating, minimal Multi- composite systems can be used for various plating processes, including but not limited to plating multiple layers at defects, or other plating processes where two or more composites can be beneficial to the plating process. Intended.

[0020] FIG. 1 is a top view illustrating one embodiment of an electrochemical processing system (ECP) 100 of the present invention. The ECP system 100 generally includes a processing base 113 with a robot 120 positioned at the center. The robot 120 generally includes one or more robot arms 122, 124 configured to support a substrate. Further, the robot 120 and its associated arms 122, 124 are generally configured to extend, rotate, and move vertically so that the robot 120 is positioned at the base 113 and has a plurality of processing positions 102, 104, 106, 108, 110, 112, 114, 116 can be inserted and removed.

  [0021] The ECP system 100 further comprises a factory interface (FI) 130. The FI 130 generally includes at least one FI robot 132 positioned near the FI side adjacent to the processing base 113. This position of the robot 132 allows the robot to access the substrate cassette 134, remove the substrate 126 therefrom, and then deliver the substrate 126 to one of the processing cells 114, 116 to initiate the processing sequence. Is acceptable. Similarly, the robot 132 can be used to retrieve a substrate from one of the processing cells 114, 116 after the substrate processing sequence is complete. In this state, the robot 132 returns the substrate 126 to one of the cassettes 134 so that it can be removed from the system 100. In addition, the robot 132 is configured to access an anneal chamber 135 positioned to communicate with the FI 130. The anneal chamber 135 generally includes a two-position anneal chamber in which a cooling plate or position 136 and a heating plate or position 137 are positioned adjacent to each other, for example, near the substrate, for example, between the two stations. The robot 140 is positioned. The robot 140 is generally configured to move a substrate between a heating plate 137 and a cooling plate 136.

  [0022] In general, the processing locations 102, 104, 106, 108, 110, 112, 114, 116 may be a number of processing cells used in electrochemical plating platforms. More particularly, these processing locations are beneficially used in connection with electrochemical plating cells, rinse cells, bevel cleaning cells, spin rinse drying cells, substrate surface cleaning cells, electroless plating cells, metrology inspection stations, and plating platforms. It may be configured as other possible cells or processes.

  FIG. 2A is a cross-sectional view illustrating one embodiment of a processing cell that can be implemented at any one of the processing locations 102, 104, 106, 108, 110, 112, 114, 116 of the processing system 100. (FIG. 2A shows an example of an electrochemical plating cell). In general, however, the exemplary processing system 100 is configured to include four electrochemical plating cells at the processing locations 102, 104, 112 and 110. Processing locations 106 and 108 are generally configured as edge bead removal or bevel cleaning chambers. Furthermore, the processing locations 114 and 116 are generally configured as a substrate surface cleaning chamber and a spin rinse drying chamber, which may be positioned in a stacked manner, i.e., one above the other. However, the invention is not limited to a particular order or arrangement of cells, as various combinations and arrangements can be implemented without departing from the scope of the invention.

[0024] Returning to Figure 2A, the electrochemical processing cell 102 generally includes a head assembly 2 1 0, an anode assembly 220, an inner basin 272, and an external bowl 240. The outer basin 240 is coupled to the base 108 and surrounds the inner basin 272. The inner and outer basins 272, 240 are typically manufactured from an electrically insulating material that is compatible with the process chemistry, such as ceramic, plastic, plexiglas (acrylic resin), lexan, PVC, CPVC or PVDF. Alternatively, the inner and outer basins 272, 240 are formed from a metal such as stainless steel, nickel or titanium and are compatible with Teflon, fluoropolymer, PVDF, plastic, rubber, and plating fluids. An insulating layer, such as other combinations of possible materials, may be coated so that it can be electrically isolated from the electrodes (ie, the anode and cathode of the electroplating system). The inner basin 272 is typically configured to match the plated surface of the substrate, and the shape of the substrate being processed by the system is generally circular or rectangular. In one embodiment, the inner basin 272 is a cylindrical ceramic tube whose inner diameter is approximately the same size or slightly larger than the diameter of the substrate to be plated with the cells 102. The outer basin 272 generally includes a channel 248 for capturing plating fluid flowing out of the inner basin 272. The outer basin 272 also has an outlet 218 formed therethrough that couples the channel 248 to a regeneration system for processing, recycling and / or disposal of spent plating fluid.

[0025] The head assembly 220 is attached to the head assembly frame 252. The head assembly frame 252 includes a mounting post 254 and a cantilever arm 256. The mounting post 254 is coupled to the base 108 of the processing system 100, and the cantilever arms 256 generally extend laterally from the top of the mounting post 254 and rotate about the vertical axis of the mounting post 254. Is adapted to allow movement of the head assembly 2 10 onto or beyond the pans 240,272. The head assembly 2 10 is generally fixed to a mounting plate 260 disposed at the distal end of the cantilever arm 256. The lower end of the cantilever arm 256 is connected to a cantilever arm actuator 268 such as an air cylinder attached to a mounting post 254. The cantilever arm actuator 268 pivotally moves the cantilever arm 256 relative to the joint between the cantilever arm 256 and the mounting post 254. When the cantilever arm actuator 268 is retracted, the cantilever arm 256 moves the head assembly 2 10 away from the anode assembly 2 10 located in the internal basin 272 and moves the anode assembly 220 to the first position. Provide the space needed to be removed from and / or replaced with one processing cell 102. When the cantilever arm actuator 268 is extended, the cantilever arm 256, the head assembly 2 1 0 moves in the axial direction toward the anode assembly 2 1 0, thereby positioning the substrate of the head assembly 220 to the processing position. The head assembly 220 can also tilt or direct the substrate held therein at an angle from the horizontal.

The head assembly 2 10 generally includes a substrate holder assembly 250 and a substrate assembly actuator 258. The substrate assembly actuator 258 is attached to a mounting plate 260 and includes a head assembly shaft 262 that extends downward through the mounting plate 260. The lower end of the head assembly shaft 262 is connected to the substrate holder assembly 250 to position the substrate holder assembly 250 at the processing position and the substrate loading position. The substrate assembly actuator 258 may be further configured to provide rotational movement to the head assembly 2 10 . In one embodiment, the head assembly 220 is rotated from about 2 rpm to about 50 rpm during the electroplating process, but may be rotated from about 5 to about 20 rpm. The head assembly 2 10 also rotates when it is lowered to position the substrate in contact with the plating solution in the processing cell and when it is raised to remove the substrate from the plating solution in the processing cell. be able to. The head assembly 2 10 may be rotated at a high speed (ie,> 20 rpm) to facilitate removal of residual plating solution from the head assembly 2 10 and substrate after it has been lifted from the processing cell. .

  [0027] The substrate holder assembly 250 generally includes a thrust plate 264 and a cathode contact ring 266. The cathode contact ring 266 is configured to make electrical contact with the surface of the substrate to be plated. Typically, the substrate has a metal seed layer, such as copper, deposited on the feature side of the substrate. A power source 246 is coupled between the cathode contact ring 266 and the anode assembly 220 to provide an electrical bias that drives the plating process.

  [0028] Thrust plate 264 and cathode contact ring 266 are suspended from hanger plate 236. The hanger plate 236 is coupled to the head assembly shaft 262. Cathode contact ring 266 is coupled to hanger plate 236 by hanger pins 238. The hanger pin 238 allows the cathode contact ring 266 to move closer to the hanger plate 236 when fitted to the inner basin 272, and thus the substrate held by the thrust plate 264 During processing, sandwiching between the hanger plate 236 and the thrust plate 264 can ensure good electrical contact between the seed layer of the substrate and the cathode contact ring 266.

  [0029] The anode assembly 220 is generally positioned within the lower portion of the inner basin 272 under the substrate holder assembly 250. The anode assembly 220 generally includes one or more anodes 244 and a diffusion plate 222. The anode 244 is typically disposed at the lower end of the internal basin 272 and the diffusion plate 222 is disposed between the anode 244 and the substrate held on top of the internal basin 272 by the substrate holder assembly 250. . The anode 244 and the diffusion plate 222 are generally maintained in a spaced relationship by an insulating spacer 224. The diffuser plate 222 is typically secured substantially across the internal opening of the internal basin 272. The diffuser plate 222 is generally capable of penetrating the plating solution and is typically made of a plastic or ceramic material, eg, an olefin such as a spin bonded polyester film. The diffuser plate 222 also generally serves as a flow regime for improving flow uniformity across the surface of the substrate being plated. The diffuser plate 222 also attenuates electrical variations in the electrochemical cell, i.e., acts to control the electrical flux, improving plating uniformity. Alternatively, the diffuser plate 222 may be made of a hydrophilic plastic, such as treated PE, PVDF, PP, or other porous or permeable material that provides electrical resistance damping properties.

  [0030] The anode assembly 220 may include a consumable anode 244 that serves as a metal source for the plating process. Alternatively, the anode 244 may be a non-consumable anode and the metal to be electroplated is supplied in the plating solution from the plating solution delivery system 111. The anode assembly 220 may be a self-enclosing module having a porous enclosure preferably made of the same metal to be electroplated as copper. Alternatively, the enclosure may be made of a porous material such as a ceramic or polymer membrane. Consumable and non-consumable anodes include, for example, copper / doped copper and platinum, respectively. The anode 244 is typically a metal particle, a wire and / or a perforated sheet and is typically a material to be deposited on the substrate, such as copper, aluminum, gold, silver, platinum, tungsten, copper phosphate, noble metal, Alternatively, it is manufactured from other materials that can be electrochemically deposited on the substrate. The anode 244 may be porous, perforated, permeable, or otherwise configured to allow the plating solution to pass through. Alternatively, the anode 244 may be a solid. Compared to a non-consumable anode, a consumable (ie, soluble) anode provides a plating solution that does not generate gas and minimizes the need to constantly replenish the plating solution with metal. In the embodiment shown in FIG. 2A, the anode 244 is a solid copper disk.

  [0031] Electrolyte inlet 216 is formed through internal basin 272 and is coupled to plating solution delivery system 111. The plating solution entering the internal basin 272 via the electrolyte inlet 216 flows through or around the anode assembly 220 and rises toward the surface of the substrate positioned at the upper end of the internal basin 272. The plating solution flows across the substrate surface and then flows through a slot (not shown) in the cathode contact ring 266 to a flow path formed in the outer basin 240. A bias applied between the substrate (via the cathode contact ring 266) by the power source 246 and the anode 244 deposits plating fluid and / or metal ions from the anode on the surface of the substrate. Processing cells that can be adapted to benefit from the present invention include, for example, U.S. patent application Ser. No. 09 / 905,513 filed Jul. 13, 2001, and U.S. patent filed Jan. 30, 2002. No. 10 / 061,126, both of which are hereby incorporated by reference in their entirety.

  [0032] FIG. 2B is a partial cross-sectional view of another embodiment of a processing cell, and in particular shows an example of an electrochemical plating cell 200. The electrochemical plating cell 200 generally includes an outer basin 201 and an inner basin 202 positioned therein. The inner basin 202 is generally configured to contain a plating solution that is used to plate a metal, such as copper, on the substrate during the electrochemical plating process. During the plating process, the plating solution is generally continuously fed to the inner basin 202 (eg, at about 1 gallon / min for a 10 liter plating cell), and therefore the plating solution is fed into the inner basin 202. Always overflows to the outer deep plate 201. The overflowed plating solution is then collected by the outer basin 201 and is drained from there for recirculation to the inner basin 202. The plating cell 200 is generally positioned at an angle of inclination, i.e., the frame portion 203 of the plating cell 200 is generally raised on one side so that each element of the plating cell 200 is inclined from about 3 ° to about 30 °. . Therefore, in order to accommodate a sufficiently deep plating solution in the inner basin 202 during the plating operation, the uppermost portion of the basin 202 is extended upward on one side of the plating cell 200, so The top is generally horizontal, allowing the plating solution supplied thereto to continuously overflow around the basin 202.

[0033] The frame member 203 of the plating cell 200 generally includes an annular base member 204 secured to the frame member 203. Since the frame member 203 is lifted on one side, the upper surface of the base member 204 is generally inclined from the horizontal at an angle corresponding to the angle of the frame member 203 relative to the horizontal position. The base member 204 is formed with an annular or disc-shaped recess, and the annular recess is configured to receive the disc-shaped anode member 205. The base member 204 further has a plurality of fluid inlet / outlet ports 209 positioned on the lower surface thereof. Each of the fluid inlet / outlets 209 is generally configured to individually supply fluid to or discharge fluid from the anode compartment or cathode compartment of the plating cell 200. The anode member 205 generally includes a plurality of slots 207 formed therethrough, and these slots 207 are generally positioned in parallel orientations across the surface of the anode 205. This parallel orientation allows a high concentration of fluid generated at the anode surface to flow down across the anode surface and into one of the slots 207. The plating cell 200 further includes a membrane support assembly 206. The membrane support assembly 206 is generally fixed at its outer periphery to the base member 204, and its interior region is configured to allow fluid to pass through. A membrane 208 is stretched across the support 206 and serves to fluidly separate the catholyte and anolyte chamber portions of the plating cell. The membrane support assembly may include an O-ring type seal positioned near the periphery of the membrane, which seals fluid from one side of the membrane secured to the membrane support 206 to the other side of the membrane. Is configured to prevent flow. Diffusion plate 2 22 is positioned over the member Blaine 208, which is the same as the structure of the diffusion plate 222 shown in Figure 2A.

  [0034] In operation, assuming that a tilted implementation is used, the plating cell 200 generally immerses the substrate in a plating solution contained in an internal basin 202. The substrate is immersed in a plating solution that generally includes copper sulfate, chlorine, and one or more organic plating additives (such as leveling agents, inhibitors, accelerators, etc.) configured to control the plating parameters. And an electrical bias is applied between the seed layer on the substrate and the anode 205 positioned in the plating cell. This electrical bias is generally configured to deposit metal ions that migrate through the plating solution onto the substrate surface, which is the cathode. In this embodiment of the plating cell 200, separate fluid solutions are supplied to the volume above the membrane 208 and the volume below the membrane 208. Generally, the volume above the membrane is designated as the cathode compartment or region because it is the region where the cathode or plating electrode is positioned. Similarly, the volume below membrane 208 is generally designated as the anode compartment or region since it is the region where the anode is located. Each anode and cathode region is generally fluidly separated from each other via membrane 208 (which is generally an ionic membrane). Thus, the fluid supplied to the cathode compartment is generally a plating solution that contains all the components necessary to support the plating operation, while the fluid supplied to the anode compartment is typically, for example, a copper sulfate solution. Such a solution does not contain the plating solution additive present in the cathode chamber. Further details regarding the construction and operation of the exemplary plating cell shown in FIG. 2B can be found in commonly assigned US patent application Ser. No. 10 / 268,284, filed Oct. 9, 2002, entitled “ELECTROCHEMICAL PROCESSING CELL”. Can see.

[0035] FIG. 3 is a schematic diagram illustrating one embodiment of a plating solution delivery system 111. As shown in FIG. The plating solution delivery system 111 is generally configured to supply the plating solution into the processing position of the system 1 11 that require plating solution. More specifically, the plating solution delivery system is further configured to supply a different plating solution or chemical to each of the processing locations. For example, the delivery system can supply a first plating solution or chemical to the processing cells 110, 112 while supplying a different plating solution or chemical to the processing cells 102, 104. Individual plating solutions are generally separated for use in a single plating cell and therefore do not present the problem of cross contamination with different chemicals. However, embodiments of the present invention also contemplate that two or more cells may share a common chemical that is different from another chemical supplied to another plating cell of the system. These features are effective because they allow multiple chemical plating processes on a single platform by allowing multiple chemicals to be supplied to a single processing platform.

  [0036] In another embodiment of the present invention, a first plating solution and a separate and distinct second plating solution may be sequentially supplied to a single plating cell. Normally, supplying two separate chemicals to a single plating cell requires that the plating cell be drained and / or purged between each chemical, but the first plating solution and the second If the mixing ratio of the plating solution is less than about 10%, it is not harmful to the film characteristics.

[0037] More specifically, the plating solution delivery system 111 typically includes a plurality of additive source 302 and at least one electrolyte source 304 fluidly coupled to each processing cell in the system 1 11 through the manifold 332 Yes. Typically, the additive source 302 includes an accelerator source 306 A , a leveler source 308 A, and an inhibitor source 310 A. Accelerator source 306 A is typically adapted to provide an accelerator material that is absorbed by the surface of the substrate and locally accelerates the current at a given voltage at the absorbed location. The accelerator includes, for example, a sulfide-based molecule. The leveler source 308 A is adapted to provide a leveler material that serves to facilitate flat plating. The leveling agent is, for example, a long chain polymer containing nitrogen. Inhibitor source 310 A is adapted to provide an inhibitor material that tends to reduce current where it is absorbed (usually the upper edge / corner of the high aspect ratio feature). Therefore, the inhibitor slows down the plating process at these locations, thereby reducing premature feature closure before the feature is completely filled and minimizing the formation of harmful voids. Limit. Inhibitors include, for example, polymers of polyethylene glycol, mixtures of ethylene oxide and propylene oxide, or copolymers of ethylene oxide and propylene oxide.

[0038] In order to prevent exhaustion of the additive source and to minimize waste of the additive during bulk container replacement, each of the additive sources 302 is typically placed in a small buffer container 306B, 308B, 310B . A combined large or bulk storage vessel 306A, 308A, 310A is provided. The buffer containers 306B, 308B, 310B are typically filled from the bulk storage containers 306A, 308A, 310A , and therefore the bulk containers can be removed for replacement without affecting the operation of the fluid delivery system. This is because the associated buffer container can supply certain additives to the system during bulk container replacement. The volume of the buffer containers 306B, 308B, 310B is usually significantly smaller than the volume of the bulk containers 306A, 308A, 310A . This is sized to contain enough additive for 10 to 12 hours of uninterrupted operation. This provides sufficient time for the operator to change the bulk container when the bulk container is empty. If a buffer vessel is not present and uninterrupted operation is desired, the bulk vessel must be replaced before it is emptied, thus leading to significant waste of additives.

  [0039] In the embodiment shown in FIG. 3, a metering pump 312 is coupled between a plurality of additive sources 302 and a plurality of processing cells. The metering pump 312 generally includes at least first to fourth inlet ports 322, 324, 326, 328. For example, the first inlet port 322 is generally coupled to the accelerator source 306, the second inlet port 324 is generally coupled to the leveler source 308, and the third inlet port 326 is generally inhibited. In addition to the agent source 310, the fourth inlet port 328 is generally coupled to the electrolyte source 304. The outlet 330 of the metering pump 312 is typically coupled to the processing cell via the manifold 332 by an outlet line 340, where a mixture of sequentially supplied additives (ie, at least one accelerator or leveling agent). And / or an inhibitor) is combined with the electrolyte supplied from the electrolyte source 304 via the first delivery line 350 to the manifold 332 to form the first or second plating solution as required. Can do. The metering pump 312 can be any metering device (s) adapted to supply a measured amount of the selective additive to the processing cells 102, 104. Metering pump 312 may be a rotary metering valve, solenoid metering pump, diaphragm pump, syringe, peristaltic pump, or other positive displacement pump used alone or coupled to a flow sensor. In addition, the additive can be pressurized and coupled to the flow sensor, coupled to the liquid mass flow controller, or a pressurized dispensing container that is acceptable for flowing an electrochemical plating solution to the plating cell. Or it can also measure by the weight utilization load cell measurement of another fluid measuring device. In one embodiment, the metering pump comprises a rotating and reciprocating ceramic piston that propels a predetermined additive of 0.32 ml / cycle.

[0040] In another embodiment of the present invention, the fluid delivery system can be configured to provide a second completely different plating solution and associated additives. For example, in this embodiment, for example, two separate plating solution from the manufacturer to provide the processing system 1 11 the ability to use different basic electrolyte solution (contained in the container 3 1 4 solution similar to the ) Can be implemented. In addition, additional sets of additive containers can be implemented to accommodate the second basic plating solution. Hence, this embodiment of the present invention, while allowing the fed first chemical substance (chemical substance provided by the first manufacturer) to one or more plating cells of system 1 11, the second allowing to feed (chemicals provided by the second manufacturer) to one or more plating cell system 1 11 chemicals. Each chemical generally has its own associated additive, but the amount of chemical mating from one or more additive sources does not exceed the scope of the present invention.

[0041] To implement a fluid delivery system capable of supplying two separate chemicals from separate basic electrolytes, a replica of the fluid delivery system shown in FIG. 3 is connected to the processing system. More specifically, the fluid delivery system shown in FIG. 3 generally includes a second set of additive containers 302, a second pump assembly 330, and a second manifold 332 (a shared manifold is also possible). Will be changed as follows. In addition, a separate source of virgin replenisher / basic electrolyte 304 is also provided. Although additional hardware is configured with the same configuration as the hardware shown in FIG. 3, the second fluid delivery system is generally parallel to the illustrated or first fluid delivery system. Therefore, this configuration is implemented, it is possible to supply the basic chemical substances with combination of available additives to one or more processing cells of the system 1 11.

[0042] The manifold 332 is typically configured to interface with a bank of valves 334. Each valve of the valve bank 334 may be selectively opened and closed from the manifold 332 to direct the 1 Tsue fluid processing cell plating system 1 11. Manifold 332 and valve bank 334 can optionally be configured to support selective fluid delivery to an additional number of processing cells. In the embodiment shown in FIG. 3, the manifold 332 and the valve bank 334, a chemical substance and its components used in the system 1 11 in different combinations, without interrupting the process, the sample port 336 to allow the sample I have.

  [0043] In certain embodiments, it may be desirable to purge metering pump 312, outlet line 340 and / or manifold 332. To facilitate such purging, the plating solution delivery system 111 is configured to supply at least one of manufacturing and / or purge fluid. In the embodiment shown in FIG. 3, the plating solution delivery system 111 includes a deionized water source 342 and a non-reacting gas source 344 coupled to the first delivery line 350. The non-reactive gas source 344 can supply a non-reactive gas such as an inert gas, air, or nitrogen via the first delivery line 350 and flow from the manifold 332. Deionized water can be supplied from the deionized water source 342 in addition to or in lieu of the non-reacting gas and flow through the manifold 332. Further, an electrolytic solution from the electrolytic solution source 304 may be used as a purge medium.

[0044] A second delivery line 352 is provided between the first gas delivery line 350 and the metering pump 312. The purge fluid includes at least one of electrolyte, deionized water, or non-reactive gas from each source 304, 342, 344, which is metered from the first delivery line 350 via the second gas delivery line 352. It can be turned to the pump 312. This purge fluid is propelled from the outlet line 340 to the manifold 332 via the metering pump 312. Valve bank 334 typically directs the purge fluid from the discharge port 3 8 8 to the playback system 232. For simplicity, various other valves, regulators and other flow control devices are not described and / or shown here.

[0045] In one embodiment of the present invention, a first chemical that facilitates filling the features on the semiconductor substrate with copper may be provided to the manifold 332. The first chemical comprises about 30 to about 65 g / l copper, about 55 to about 85 ppm chlorine, about 20 to about 40 g / l acid, and about 4 to about 7.5 ml / L accelerator. And about 1 to 5 ml / L of inhibitor, and no leveling agent. This first chemical can be delivered from the manifold 332 to the first plating cell 102 to substantially fill the features deposited on the substrate with metal. Since the first chemical generally does not completely fill the feature and is inherently a slow deposition rate, the first chemical is optimal for improving the gap fill performance and defect ratio of the deposited layer. can do. Second chemical supplement with different chemicals from the first chemical substance, through the manifold 332 can be supplied to another plating cell system 1 11, wherein the second chemical substance is copper on a substrate Is configured to facilitate flat bulk deposition. This second chemical may be, for example, about 35 to about 60 g / l copper, about 60 to about 80 ppm chlorine, about 20 to about 40 g / l acid, and about 4 to about 7.5 ml / L. Accelerators, about 1 to about 4 ml / L of inhibitor, and about 6 to about 10 ml / L of leveling agent can be included. The second chemical is delivered from the manifold 332 to the second processing cell and performs an efficient bulk metal deposition process on the metal deposited during the feature filling and planarization deposition steps to The remaining part can be filled. Since the second chemistry typically fills the top of the feature, the second chemistry is optimal for promoting planarization of the deposited material without substantially affecting the substrate throughput. It can be. Thus, a two-step, deposition process with different chemical materials can achieve both rapid deposition and good planarization of the deposited film.

[0046] When used in processing cell in need anode solution as a plating cell 200 of FIG. 2B, the plating solution delivery system 111 generally includes an anode fluid flow path 380 that is coupled to the inlet 209 of plating cell 200 . The anolyte flow path 380 includes a plurality of additive sources 382 that are coupled to a manifold 386 by a metering pump 384, which is selectively metered from one or more of the sources 382. Additives that are synthesized with the anolyte in (not normally used) are directed to processing cells (such as cell 200) that require an anolyte solution during the plating process. The anolyte may be supplied by an anolyte source 388.

  FIG. 4 illustrates one embodiment of a processing cell 400 configured to remove deposition material from the edge of the substrate 402. The processing cell 400 includes a housing 404 in which a substrate chuck 406 is disposed. The substrate chuck 406 includes a plurality of arms (shown as 408A-C) extending from the central hub 410. Each arm 408A-C includes a substrate clamp 412 disposed at the distal end of the arm. Hub 410 is coupled by shaft 414 to motor 416 located outside housing 404. The motor 416 is adapted to rotate the chuck 406 and the substrate 402 disposed thereon during processing. During processing, the substrate 402 is rotated, during which etchant is delivered from the etchant source 418 to the edge of the substrate. The etchant is typically delivered to the edge of the substrate through a plurality of upper nozzles 420 positioned within the housing 404 in a direction that directs the etchant flowing therefrom radially outward relative to the surface of the substrate. The processing cell 400 can also include a plurality of lower nozzles 422 coupled to an etchant source 418 that directs the etchant to the edge of the substrate on the side of the substrate opposite the upper nozzle 420. Adapted. The etchant is typically delivered to the substrate 402 while the substrate rotates at about 100 to about 1000 rpm. The nozzles 420, 422 are typically configured to direct the etchant substantially tangentially in the substrate, typically at an angle of about 10 to about 70 °, or at an angle of about 10 to about 30 °, where The angle is defined as the angle between the substrate surface and the fluid flow direction, ie the longitudinal axis of the dispensing nozzle. In one embodiment, the etchant is a combination of an acid and an oxidizing agent, such as sulfuric acid, nitric acid, citric acid, or phosphoric acid combined with hydrogen peroxide, which is a substrate exclusion zone (generally a substrate The deposited copper is removed from the outer ring of the surface (generally about 2 mm or 3 mm in width).

[0048] After the deposited material is removed from the edge of the substrate, deionized water or other cleaning agent is supplied through nozzles 420, 422 to clean the substrate surface. The substrate 402 is typically rotated at about 200 rpm to remove etchant, deionized water, and other impurities from each of the upper and lower surfaces of the substrate 402. Various fluids dispensed during treatment, from the housing 404, and is discharged through the port 42 5 formed on the bottom of the housing 404. Two processing cells configured to remove deposited material from the edge of a substrate that can be adapted to benefit from the present invention are described in US patent application Ser. No. 09 / 350,212 filed Jul. 9, 1999. And US patent application Ser. No. 09 / 614,406, filed Jul. 12, 2000, both of which are hereby incorporated by reference in their entirety.

[0049] FIG. 5 is a partial cross-sectional view of a processing cell 500 configured to spin, rinse, and dry the substrate 502 after processing. The processing cell 500 includes a housing 504 in which a substrate chuck 506 is disposed. The substrate chuck 506 includes a plurality of arms (shown as 508A-C) extending from the central hub 510. Each arm 508A-C includes a substrate clamp 512 disposed at the distal end of the arm. Hub 51 0, the shaft 514 is coupled to a motor 516 disposed outside of the housing 504. Motor 516 is adapted to rotate chuck 506 and substrate 502 disposed thereon during processing. During processing, the substrate is rotated while a cleaning agent such as deionized water or alcohol is delivered from the fluid source 518 to the top surface of the substrate 502, which is positioned on the chuck 506 within the housing 504. The plurality of upper nozzles 520 are performed. The back surface of the substrate 502 is treated with at least one of a cleaning or dissolving agent dispensed from a plurality of lower nozzles 522 disposed under the chuck 506 and coupled to a fluid source 518. Solubilizers include, for example, hydrochloric acid, sulfuric acid, phosphoric acid, hydrofluoric acid, among others. The fluid is typically delivered to the substrate while the substrate rotates at about 4 to 4000 rpm. After the deposited material has been removed from the edge of the substrate, deionized water or other cleaning agent is supplied through nozzles 520, 522 to clean the substrate surface. The substrate 502 is typically rotated at about 100 to about 5000 rpm to dry the substrate while removing liquid and other impurities from each of the top and bottom surfaces of the substrate 502. Various fluids dispensed during processing are drained from the housing 504 via a port 524 formed in the bottom of the housing 504. One processing cell configured to clean and dry substrates that can be adapted to benefit from the present invention is described in US Pat. No. 6,290, dated September 18, 2001, which is hereby incorporated by reference in its entirety. 865.

[0050] In operation, an embodiment of the present invention is generally a plating system having a plurality of plating cells on a single integral platform, and a fluid delivery system for the plating system places a plurality of composites into the plating cell. Provide a plating system that can be supplied. More particularly, for example, assuming that four individual plating cells are positioned on a common system platform, the fluid delivery system of the present invention can supply a different composite to each of the four plating cells. Different compositions may include different basic solutions or virgin replenishment solutions, and may further include various additives at various concentrations including the absence of selected additives.

[0051] Multi- composite capability for a single platform has advantages in many areas of semiconductor processing. For example, the ability to deliver multiple composites to multiple plating cells on an integral platform can benefit from the reliable properties of multiple composites on a single platform with a single plating system. To be able to. The multi- composite capacity can, for example, adjust the first plating solution or composite for a feature filling process (a low defect but slow deposition rate) while the second composite is a feature bulk. Since it can be tailored to the filling process (a faster deposition process that can be performed when the feature is primarily filled by the first process), it can be applied to feature filling and bulk filling processes. Further, the multi- composite plating system can use the first plating composition to facilitate the attachment of the first material to the barrier layer, and then use the second composite to barrier-layer plating. Facilitates direct plating on the barrier layer as the second material can be plated onto the first material layer on top of the barrier layer to fill the feature without encountering adhesion challenges . Furthermore, the multi- composite system can use the first composite to plate the alloy layer, and then use the second composite to use a different layer or another alloy over the already deposited layer. It is also useful for alloy plating processes where layers can be plated. Furthermore, the multi-composition process, using a first composite configured to plating the first layer with a minimum of defects, then with minimal defects to optimize throughput of the first layer By using a second composite configured to plate the second layer on top, it can be used to substantially improve the defect ratio in the semiconductor substrate plating process.

  [0052] While embodiments of the invention have been described above, other and further embodiments are contemplated without departing from the scope of the invention as defined in the basic scope of the invention and the claims. You can also put it out.

It is a top view which shows one Embodiment of the electrochemical plating system of this invention. 1 is a partial cross-sectional view of one embodiment of an electrochemical processing cell. FIG. 6 is a partial cross-sectional view of another embodiment of an electrochemical processing cell. 1 is a schematic diagram of one embodiment of a plating solution delivery system. FIG. 6 is a partial cross-sectional view illustrating one embodiment of a processing cell configured to remove deposited material from an edge of a substrate. FIG. 6 is a partial cross-sectional view illustrating one embodiment of a processing cell configured to spin, rinse, and dry a substrate.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Electrochemical processing system, 102, 104, 106 , 108, 110, 112, 114, 116 ... Processing position, 111 ... Plating solution delivery system, 108 ... Base, 113 ... Processing base, 120 ... Robot, 122, 124 ... robot arm, 126 ... substrate, 130 ... factory interface, 132 ... FI robot, 134 ... substrate cassette, 135 ... annealing chamber, 136 ... cooling plate, 137 ... heating plate, 140 ... substrate transfer robot, 200 ... electrochemical plating cell , 201 ... external basin, 202 ... internal basin, 203 ... frame portion, 204 ... annular base member, 205 ... anode member, 207 ... slot, 208 ... membrane, 210 ... head assembly, 216 ... electrolyte inlet, 218 ... Exhaust port, 220 ... Ano 222, diffusion plate, 224, spacer, 236, hanger plate, 238, hanger pin, 240, external deep plate, 244, anode, 248, channel, 250, substrate holder assembly, 252, head assembly frame, 254,. Mounting post, 256 ... cantilever arm, 258 ... substrate assembly actuator, 260 ... mounting plate, 262 ... shaft, 264 ... slice plate, 266 ... cathode contact ring, 268 ... actuator, 272 ... inner dish, 302 ... additive Source, 304 ... Electrolyte source, 312 ... Metering pump, 332 ... Manifold

Claims (23)

A system platform in which a plurality of electrochemical plating cells are positioned;
At least one robot positioned to transfer a substrate between the plurality of plating cells;
A first fluid delivery system in fluid communication with a first plating cell of the plurality of plating cells ;
A second fluid delivery system in fluid communication with a second plating cell of the plurality of plating cells;
With
Said first fluid delivery system and the second fluid delivery system, in each of the first plating cell and the second plating cell configured to provide different composite having a plurality of components simultaneously, electrical chemical treatment system. The first fluid delivery system includes:
A first plurality of additive sources;
A metering pump in fluid communication with each of the additive sources;
A first virgin electrolyte source in fluid communication with the metering pump;
In the measurement pump at the inlet, at the outlet a first manifold in fluid communication with the plurality of plating cells, the plurality of plating cells of selected one to a particular chemical structure have been the first manifold to direct When,
The electrochemical processing system of claim 1, comprising: The apparatus further comprises a second plurality of additive sources and a second virgin electrolyte source, wherein the second plurality of additive sources and the second virgin electrolyte source are selectively in fluid communication with the plurality of plating cells. The electrochemical processing system of claim 1, wherein the electrochemical processing system is in fluid communication with a second manifold. The first plurality of additive sources is:
A first source providing an electrochemical plating accelerator;
A second source providing an electrochemical plating leveling agent;
A third source providing an electrochemical plating inhibitor;
The electrochemical processing system according to claim 2, comprising: Each of the first plurality of additive sources includes
At least one bulk additive container;
At least one buffer container having a volume smaller than the bulk additive container and in fluid communication with the associated bulk additive container and the metering pump;
The electrochemical processing system of claim 2, further comprising: The electrochemical processing system of claim 1, further comprising at least one annealing chamber in communication with the system platform. The electrochemical processing system of claim 1, wherein the first fluid delivery system is further configured to supply an anode solution to the anode chamber of the plating cell and a cathode solution to the cathode chamber of the plating cell. A processing system base having a plurality of processing cell locations;
At least two electrochemical plating cells positioned at the two processing cell locations;
At least one spin rinse drying cell positioned at one of the processing cell locations;
At least one substrate bevel cleaning cell positioned at one of the processing cell locations;
A multi- composite plating solution delivery system in fluid communication with the at least two electrochemical processing cells, wherein different electrochemical plating solutions having a plurality of components are simultaneously delivered to each of the at least two electrochemical processing systems. A multi-composite plating solution delivery system, configured as follows:
An electrochemical processing system comprising:
The multi-composite plating solution delivery system is
Measuring pump,
A plurality of plating solution additive containers in fluid communication with the metering pump;
At least one first virgin electrolyte solution container in fluid communication with the metering pump; and a plating solution in fluid communication with an outlet of the metering pump and selectively in fluid communication with each of the at least two electrochemical plating cells. Distribution manifold,
Including an electrochemical processing system.   The electrochemical processing system of claim 8, wherein the plurality of plating solution additive containers comprise a bulk container in fluid communication with a buffer container, and the buffer container is in fluid communication with the metering pump.   The metering pump comprises a high precision fluid delivery pump having a plurality of fluid inlets and at least one fluid outlet, and the metering pump mixes fluid components received at the plurality of fluid inlets in a predetermined ratio. The electrochemical processing system of claim 8, wherein the electrochemical processing system is configured to deliver a predetermined ratio mixture of the fluid components from the at least one fluid outlet. The multi- composite plating solution delivery system further includes a second virgin electrolyte container in fluid communication with the metering pump, the second virgin electrolyte container being connected to the at least one first virgin electrolyte container. The electrochemical processing system of claim 8, wherein the electrochemical processing system is configured to provide a second virgin electrolyte different from the contained first virgin electrolyte. The electrochemical processing system of claim 8, wherein the multi- composite plating solution delivery system is configured to provide at least two different plating chemistries to the at least two electrochemical plating cells. 9. The multi- composite plating solution delivery system is configured to supply a catholyte plating solution to the catholyte region of the electrochemical plating cell and an anolyte solution to the anolyte region of the electrochemical plating cell. An electrochemical processing system according to claim 1. In a method of electrochemically plating at least one layer on a semiconductor substrate,
Positioning the substrate in a first electrochemical plating cell on an integral plating system platform for a first plating operation;
Positioning the substrate in a second plating cell on the integral plating system platform for a second plating operation;
Supplying a first electrochemical plating composition to the first plating cell in a multi- composite fluid delivery system positioned in communication with the system platform;
Supplying a second electrochemical plating composition to the second plating cell in the multi- composite fluid delivery system, wherein the first and second plating compositions are different; and
With a method. The method of claim 14, wherein the first and second electrochemical plating compositions comprise different plating solution bases. The method of claim 14, wherein the first and second electrochemical plating compositions have different additive concentrations. 15. The first electrochemical plating composition is an optimized gap filling composition and the second electrochemical plating composition is an optimized bulk filling composition. The method described. The first electrochemical plating composition is an optimized over-barrier chemical composition , and the second electrochemical plating composition is an optimized feature-filled planarization composition . The method according to claim 14. 15. The first electrochemical plating composition is an optimized alloy plating composition , and the second electrochemical plating composition is an optimized copper plating composition. the method of.   The method of claim 14, further comprising rinsing the semiconductor substrate between the first plating operation and the second plating operation.   The method of claim 14, further comprising spin drying the semiconductor substrate between the first plating operation and the second plating operation.   The method of claim 14, wherein the first plating operation is a copper plating process and the second plating operation is an alloy plating process. The method of claim 14, wherein the first plating operation is a defect reduction plating process.

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