JP2017186677A - Electrolytic copper plating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce an amount of a black film falling from a soluble anode as much as possible by maintaining the black film on a surface of the soluble anode consisting of phosphorous-containing copper stably.SOLUTION: An electrolytic copper plating device has a plating tank 38 holding a plating liquid inside, a soluble anode 130 consisting of phosphorus-containing copper impregnated in the plating liquid inside of the plating tank 38, and a substrate holder 18 holding a substrate W and arranging the substrate W at a position facing the anode 130 while impregnating at least a surface to be plated of the substrate W into the plating liquid inside of the plating tank 38. The phosphorus concentration of the phosphorus-containing copper is 2000-2700 mass.ppm and average crystal particle diameter of copper is 15-45 μm.SELECTED DRAWING: Figure 6

Description

  The present invention relates to an electrolytic copper plating apparatus, and in particular, a substrate such as a semiconductor wafer is held in a substrate holder while being immersed in a plating solution to form connection bumps or wiring made of copper on the substrate surface, or through-hole copper. The present invention relates to an electrolytic copper plating apparatus used for plating.

  A soluble anode made of phosphorous copper (hereinafter referred to as phosphorous copper anode) is used as an anode of an electrolytic copper plating apparatus in which a substrate such as a semiconductor wafer is held by a substrate holder and immersed in a plating solution to perform copper plating on the substrate surface. ) Is widely used. Thus, when a phosphorous copper anode is used, a blank film called a black film is uniformly formed in advance on the surface of the phosphorous copper anode by performing a blank electrolysis in which a voltage is applied between the dummy substrate and the phosphorous copper anode. Then, a voltage is applied between the phosphorous copper anode and the substrate to perform copper plating on the substrate surface. Thereby, the production | generation of monovalent copper is suppressed and formation of sludge is prevented.

  When copper plating is performed using a phosphorus-containing copper anode, the black film may fall off from the surface of the phosphorus-containing copper anode during the copper plating and float in the plating solution. When the black film floating in the plating solution adheres to the substrate, it causes a defect on the substrate.

  For this reason, there has been proposed an apparatus in which an enclosure is formed by an anode cup and a membrane, and an anode is disposed in the enclosure so that particles generated from the anode do not adhere to the substrate (see Patent Document 1). .

  In addition, there has been proposed a plating apparatus in which an anode chamber and a cathode chamber are separated by a porous permeation barrier having a multilayer structure that allows permeation of metal ions and prevents permeation of nonionic organic additives (see Patent Document 2). Also, the anode chamber and cathode chamber are made of a membrane that uses an anode having a phosphorus concentration in the anode of 200 ppm or more and an average crystal grain size of 50 μm or more, and that allows permeation of metal ions and prevents the passage of particles of 0.05 μm or more. Has been proposed (see Patent Document 3).

  Further, an anode was manufactured by hot forging a phosphorus-containing copper ingot having a copper purity of 99.99% by mass or more, a phosphorus concentration of 300 to 1000 ppm, and an oxygen content of 10 ppm or less at an initial temperature of 600 to 900 ° C. By controlling the average grain size within 30 μm or less, the technology prevents the black film from dropping from the phosphorous copper anode (see Patent Document 4), and the inside of the anode bag containing the anode is bubbled with air or oxygen And the technique which prevents the growth and fall-off | omission of the black film of the anode surface is proposed by making oxygen dissolved amount in electrolyte solution 5 ppm or more (refer patent document 5).

US Pat. No. 6,126,798 US Pat. No. 6,527,920 US Pat. No. 6,821,407 JP 2012-57186 A JP 2011-46973 A

  However, it is generally difficult to form a black film firmly on the surface of the phosphorus-containing copper anode so as not to fall off from the surface of the anode. Moreover, in order to prevent the black film dropped from the phosphorous-containing copper anode from adhering to the substrate, it is necessary to adopt a rather complicated configuration. In particular, in order to completely prevent the black film from adhering to the substrate, a more complicated structure is required.

Since the present invention has been made in view of the above circumstances, the amount of black film that falls off the soluble anode can be reduced as much as possible by stably maintaining the black film on the surface of the soluble anode made of phosphorous copper. It is a first object of the present invention to provide an electrolytic copper plating apparatus.
In addition, even if a black film falls off from a soluble anode made of phosphorous copper, it is possible to more reliably prevent the dropped black film from adhering to the substrate with a relatively simple configuration. A second object is to provide an electrolytic copper plating apparatus.

  An electrolytic copper plating apparatus according to an aspect of the present invention includes a plating tank that holds a plating solution therein, a soluble anode made of phosphorous copper that is immersed in the plating solution inside the plating tank, and a substrate. A substrate holder for placing the substrate at a position facing the anode while immersing the substrate in a plating solution inside the plating tank, a substrate holder transporting device for transporting the substrate holder holding the substrate, and a periphery of the anode A net-like anode bag that surrounds the substrate, an adjustment plate that has an opening, is arranged between the anode and the substrate held by the substrate holder, and adjusts an electric field; and closes the opening of the adjustment plate The phosphorous copper has a phosphorus concentration of 2000 to 2700 mass ppm, and an average crystal grain size of copper. Characterized in that it is a 15Myuemu～45myuemu.

  As a result, even if the black film is peeled off from the soluble anode made of phosphorous copper (phosphorous copper anode) and the black film floats in the plating solution, the movement of the black film toward the substrate is transferred to the anode bag. Double blocking with the diaphragm can almost completely prevent the black film from adhering to the surface of the substrate.

  The phosphorus concentration of the phosphorous-containing copper is 1800 to 2700 mass ppm, and the average crystal grain size of copper is 15 μm to 45 μm.

  Thus, the surface of the phosphorous copper anode is obtained by using a soluble anode (hereinafter referred to as phosphorous copper anode) made of phosphorous copper having a phosphorus concentration of 1800 to 2700 ppm, preferably 2000 to 2700 ppm, as the anode. It has been confirmed by experiments that a black film is formed with a uniform film thickness and hardly peeled off on the surface.

  An electrolytic copper plating apparatus according to yet another aspect of the present invention includes a plating tank for holding a plating solution therein, a soluble anode made of phosphorous copper immersed in the plating solution inside the plating tank, and a substrate. A substrate holder for holding and immersing the substrate in a plating solution inside the plating tank and placing the substrate at a position facing the anode, a substrate holder transporting device for transporting the substrate holder holding the substrate, and the anode A net-like first anode bag surrounding the first anode bag, a net-like second anode bag surrounding the first anode bag, finer than the first anode bag, an opening, the anode and the substrate holder And an adjusting plate that adjusts the electric field, and the phosphorus concentration of the phosphorus-containing copper is 2000 to 2700 mass ppm, and the average crystal grain of copper It is a 15μm~45μm.

  As a result, even if the black film is peeled off from the soluble anode made of phosphorous copper (phosphorous copper anode) and the black film floats in the plating solution, the movement of the black film toward the substrate becomes the first anode. Double blocking with the bag and the second anode bag can almost completely prevent the black film from adhering to the surface of the substrate.

  An electrolytic copper plating apparatus according to yet another aspect of the present invention includes a plating tank for holding a plating solution therein, a soluble anode made of phosphorous copper immersed in the plating solution inside the plating tank, and a substrate. A substrate holder for holding and immersing the substrate in a plating solution inside the plating tank and placing the substrate at a position facing the anode, a substrate holder transfer device for transferring the substrate holder holding the substrate, and an opening And an adjustment plate arranged between the anode and the substrate held by the substrate holder to adjust the electric field, and arranged to close the opening of the adjustment plate, allowing permeation of metal ions And dividing the inside of the plating tank into an anode chamber in which the anode and the diaphragm are disposed and a cathode chamber in which the substrate held by the substrate holder is disposed. A shield box provided with an opening closed by the diaphragm at a position facing the opening of the adjustment plate, and a plating solution discharge line for extracting and discharging the plating solution in the anode chamber from the bottom of the anode chamber And the phosphorus concentration of the phosphorous-containing copper is 2000 to 2700 mass ppm, and the average crystal grain size of copper is 15 μm to 45 μm.

  As a result, even if the black film is peeled off from the soluble anode made of phosphorous copper (phosphorous copper anode) and the black film floats in the plating solution, the plating solution in which the black film floats is removed at the bottom of the anode chamber. The black film that is drawn out from the substrate and discharged, and the black film floating in the plating solution is blocked from moving from the anode chamber to the cathode chamber by the diaphragm, thereby almost completely preventing the black film from adhering to the surface of the substrate. Can do.

According to the present invention, a phosphorus-containing copper anode is obtained by using, as an anode, a soluble anode made of phosphorus-containing copper having a phosphorus concentration of 1800-2700 ppm, preferably 2000-2700 ppm. It is possible to produce a black film with a uniform film thickness that is difficult to peel off on the surface of the surface.
Also, with a relatively simple structure, even if the black film is peeled off from the soluble anode made of phosphorous copper (phosphorous copper anode), it can almost completely prevent the black film from adhering to the surface of the substrate. it can.

1 is an overall layout diagram of an electrolytic copper plating apparatus according to an embodiment of the present invention. It is a perspective view which shows the outline of the substrate holder shown in FIG. It is a top view of the substrate holder shown in FIG. It is a right view of the substrate holder shown in FIG. It is the A section enlarged view of FIG. It is a longitudinal cross-sectional view which shows the copper plating unit with which the electrolytic copper plating apparatus shown in FIG. 1 is equipped. It is a top view which shows the stirring paddle (stirring tool) of the copper plating unit shown in FIG. It is the sectional view on the AA line of FIG. It is a longitudinal cross-sectional view which shows the other example of a copper plating unit. It is a longitudinal cross-sectional view which shows the other example of a copper plating unit. It is a longitudinal cross-sectional view which shows the other example of a copper plating unit. It is a longitudinal cross-sectional view which shows the other example of a copper plating unit. It is a longitudinal cross-sectional view which shows the other example of a copper plating unit. It is a longitudinal cross-sectional view which shows the other example of a copper plating unit. It is a longitudinal cross-sectional view which shows the other example of a copper plating unit.

  Embodiments of the present invention will be described below with reference to the drawings. In the following examples, the same or corresponding elements are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1 shows an overall layout of an electrolytic copper plating apparatus in an embodiment of the present invention. As shown in FIG. 1, in this electrolytic copper plating apparatus, two cassette tables 12 on which a cassette 10 containing a substrate such as a semiconductor wafer is mounted and the positions of orientation flats, notches and the like on the substrate are aligned in a predetermined direction. An aligner 14 and a spin rinse dryer 16 that rotates the substrate after the plating process at high speed are provided. In the vicinity of the spin rinse dryer 16, there is provided a substrate attaching / detaching portion 20 for placing the substrate holder 18 and attaching / detaching the substrate to / from the substrate holder 18. In the center of these units 10, 14, 16, and 20, a substrate transfer device 22 including a transfer robot that transfers a substrate between these units is disposed.

  The substrate attaching / detaching portion 20, the stocker 24 for storing and temporarily placing the substrate holder 18, the pre-wet bath 26 for immersing the substrate in pure water, and the oxide film on the surface of the conductive layer such as the seed layer formed on the surface of the substrate. A pre-soak tank 28 for etching removal, a first cleaning tank 30a for cleaning the pre-soaked substrate together with the substrate holder 18 with a cleaning liquid (pure water or the like), a blow tank 32 for draining the substrate after cleaning, and a substrate after plating The 2nd washing tank 30b and copper plating unit 34 which wash with cleaning fluid with holder 18 are arranged in this order. The copper plating unit 34 is configured by accommodating a plurality of plating tanks 38 inside an overflow tank 36. Each of the plating tanks 38 accommodates one substrate therein and immerses the substrate in a plating solution held therein to perform plating such as copper plating on the substrate surface.

  A substrate holder transfer device 40 that employs, for example, a linear motor system is provided that is located on the side of each of these devices and transfers the substrate holder 18 together with the substrates between these devices. The substrate holder transport device 40 includes a first transporter 42 that transports a substrate between the substrate attaching / detaching unit 20, the stocker 24, the pre-wet tank 26, the pre-soak tank 28, the first cleaning tank 30a, and the blow tank 32; It has the 2nd transporter 44 which conveys a board | substrate among the 1st washing tank 30a, the 2nd washing tank 30b, the blow tank 32, and the copper plating unit 34. Only the first transporter 42 may be provided without providing the second transporter 44.

  On the opposite side of the substrate holder transfer device 40 across the overflow tank 36, there is an agitation paddle 232 (FIG. 6) that is located inside each plating tank 38 and serves as a stirring rod for agitating the plating solution in the plating tank 38. A paddle driving device 46 for driving (see) is disposed.

  The board attaching / detaching unit 20 includes a flat plate-like mounting plate 52 that is slidable in the horizontal direction along the rail 50. After placing the two substrate holders 18 in parallel in a horizontal state on the placement plate 52 and transferring the substrate between the one substrate holder 18 and the substrate transport device 22, the placement plate 52. Is slid in the horizontal direction to transfer the substrate between the other substrate holder 18 and the substrate transfer device 22.

  As shown in FIGS. 2 to 5, the substrate holder 18 can be opened and closed by a rectangular flat plate-shaped first holding member (fixed holding member) 54 made of, for example, vinyl chloride, and the first holding member 54 via a hinge 56. And a second holding member (movable holding member) 58 attached thereto. As another configuration example, the second holding member 58 is disposed at a position facing the first holding member 54, the second holding member 58 is advanced toward the first holding member 54, and the first holding member is used. The second holding member 58 may be opened and closed by being separated from 54.

  The second holding member 58 has a base 60 and a ring-shaped seal holder 62. The seal holder 62 is made of, for example, vinyl chloride, and improves sliding with the presser ring 64 described below. A substrate-side seal member 66 that seals the gap between the second holding member 58 and the substrate W when the substrate W is held by the substrate holder 18 is pressed above the seal holder 62. It protrudes toward the direction. Further, the surface of the seal holder 62 facing the first holding member 54 is in pressure contact with the first holding member 54 at an outer position of the substrate-side seal member 66, and the first holding member 54 and the second holding member 58 are in contact with each other. A holder-side seal member 68 that seals the gap is attached.

  As shown in FIG. 5, the substrate side sealing member 66 is sandwiched between the seal holder 62 and the first fixing ring 70 a and attached to the seal holder 62. The first fixing ring 70a is attached to the seal holder 62 via a fastener 69a such as a bolt. The holder side seal member 68 is sandwiched between the seal holder 62 and the second fixing ring 70 b and attached to the seal holder 62. The second fixing ring 70b is attached to the seal holder 62 via a fastener 69b such as a bolt.

  A step portion is provided on the outer peripheral portion of the seal holder 62, and a presser ring 64 is rotatably attached to the step portion via a spacer 65. The presser ring 64 is mounted so as not to escape by the outer peripheral portion of the first fixing ring 70a. The presser ring 64 is made of a material that has excellent corrosion resistance against acids and alkalis and has sufficient rigidity. For example, the presser ring 64 is made of titanium. The spacer 65 is made of a material having a low coefficient of friction, such as PTFE, so that the presser ring 64 can rotate smoothly.

  On the outer side of the presser ring 64, a plurality of clampers 74 are arranged at equal intervals along the circumferential direction of the presser ring 64. These clampers 74 are fixed to the first holding member 54. Each clamper 74 has an inverted L shape having a protruding portion protruding inward. A plurality of protrusions 64 b protruding outward are provided on the outer peripheral surface of the presser ring 64. These protrusions 64 b are arranged at positions corresponding to the positions of the clampers 74. The lower surface of the inwardly protruding portion of the clamper 74 and the upper surface of the protrusion 64b of the presser ring 64 are tapered surfaces that are inclined in opposite directions along the rotation direction of the presser ring 64. Protrusions 64 a that protrude upward are provided at a plurality of locations (for example, three locations) along the circumferential direction of the presser ring 64. Accordingly, the presser ring 64 can be rotated by rotating a rotation pin (not shown) and pushing the convex portion 64a from the side.

  With the second holding member 58 open, the substrate W is inserted into the center of the first holding member 54, and the second holding member 58 is closed via the hinge 56. By rotating the presser ring 64 in the clockwise direction and sliding the protrusion 64b of the presser ring 64 into the inner projecting part of the clamper 74, the presser ring 64 and the clamper 74 are respectively provided with tapered surfaces. The first holding member 54 and the second holding member 58 are fastened together to lock the second holding member 58. Further, the second holding member 58 is unlocked by rotating the presser ring 64 counterclockwise to remove the protrusion 64b of the presser ring 64 from the clamper 74. When the second holding member 58 is locked, the downward projecting portion of the substrate side sealing member 66 is brought into pressure contact with the outer peripheral portion of the surface of the substrate W held by the substrate holder 18. The substrate-side sealing member 66 is uniformly pressed against the substrate W, thereby sealing the gap between the outer peripheral portion of the surface of the substrate W and the second holding member 58. Similarly, when the second holding member 58 is locked, the downward projecting portion of the holder-side seal member 68 is pressed against the surface of the first holding member 54. The holder-side seal member 68 is uniformly pressed against the first holding member 54, thereby sealing the gap between the first holding member 54 and the second holding member 58.

  On the upper surface of the first holding member 54, a ring-shaped protrusion 82 that is substantially equal to the size of the substrate W is formed. The protruding portion 82 has an annular support surface 80 that contacts the peripheral edge of the substrate W and supports the substrate W. A concave portion 84 is provided at a predetermined position along the circumferential direction of the protruding portion 82.

  A pair of holder hangers 90 are provided at the end portion of the first holding member 54 of the substrate holder 18 so as to protrude outwardly as a support portion when the substrate holder 18 is transported or supported to be suspended. Further, a hand lever 92 extends between the holder hangers 90 on both sides. The substrate holder transport device 40 is configured to hold the substrate holder 18 by sandwiching the hand lever 92 of the substrate holder 18. In the stocker 24, the substrate holder 18 is vertically suspended and held by hooking a holder hanger 90 on the upper surface of the peripheral wall. Further, the holder hanger 90 of the suspended substrate holder 18 is gripped by the first transporter 42 to transport the substrate holder 18. Note that the substrate holder 18 is also suspended and held on the peripheral walls via the holder hanger 90 in the pre-wet tank 26, the pre-soak tank 28, the cleaning tanks 30a and 30b, the blow tank 32, and the copper plating unit 34.

  As shown in FIG. 3, a plurality (12 pieces in the drawing) of conductors (electrical contacts) 86 are disposed in the recess 84. These conductors 86 are respectively connected to a plurality of wires extending from connection terminals 91 provided on the holder hanger 90. The conductor 86 itself does not come into contact with the substrate W, the end of the conductor 86 is positioned outside the outer peripheral end of the substrate W, and the substrate W is placed on the support surface 80 of the first holding member 54. When placed, the elastic contact is made with the lower part of the electrical contact 88 shown in FIG.

  An electrical contact 88 electrically connected to the conductor 86 is fixed to the seal holder 62 of the second holding member 58 via a fastener 89 such as a bolt. The electrical contact 88 is formed in a leaf spring shape. The electrical contact 88 has a contact portion that is located outside the board-side seal member 66 and protrudes in the shape of a leaf spring. The electrical contact 88 is easily bent at the contact portion with springiness due to its elastic force. When the substrate W is held by the first holding member 54 and the second holding member 58, the contact portion of the electrical contact 88 is elastically applied to the outer peripheral surface of the substrate W supported on the support surface 80 of the first holding member 54. It is comprised so that it may contact.

  The second holding member 58 is opened and closed by the weight of an air cylinder (not shown) and the second holding member 58. In other words, the first holding member 54 is provided with a through hole 54 a, and an air cylinder is provided at a position facing the through hole 54 a when the substrate holder 18 is placed on the placement plate 52. The piston rod is extended, the second holding member 58 is opened by pushing the seal holder 62 of the second holding member 58 upward through the through hole 54a with the pressing rod, and the piston rod is contracted, thereby the second holding member 58. Is closed by its own weight.

  A pair of substantially T-shaped holder hangers 90 are connected to the end portion of the first holding member 54 of the substrate holder 18 and serve as a support portion when the substrate holder 18 is transported or supported by hanging. In the stocker 24, the projecting end portion of the holder hanger 90 is hooked on the upper surface of the peripheral wall so as to be suspended vertically, and the holder hanger 90 of the substrate holder 18 that is suspended is held by the first transporter 42. The substrate holder 18 is conveyed by holding it. Note that the substrate holder 18 is suspended and held on the peripheral walls of the pre-wet tank 26, the pre-soak tank 28, the cleaning tanks 30 a and 30 b, the blow tank 32, and the copper plating unit 34 via the holder hanger 90.

  FIG. 6 is a longitudinal sectional view of the copper plating unit 34 provided in the electrolytic copper plating apparatus shown in FIG. As shown in FIG. 6, the plating tank 38 is configured to hold a certain amount of plating solution therein. A bottom plate 100 is disposed in the plating tank 38, whereby the interior of the plating tank 38 is partitioned into an upper substrate processing chamber and a lower plating solution dispersion chamber 104. The interior of the upper substrate processing chamber is divided into an anode chamber 110 and a cathode chamber 112 described below. Further, the bottom plate 100 is provided with a shielding plate 106 that hangs downward and restricts the flow of the plating solution.

  A shield box 108 is disposed inside the substrate processing chamber, whereby the inside of the substrate processing chamber is divided into an anode chamber 110 inside the shield box 108 and an external cathode chamber 112. The bottom plate 100 is formed with a first plating solution circulation port 100 a that allows the cathode chamber 112 and the plating solution dispersion chamber 104 to communicate with each other. Further, the bottom plate 100 is formed with a second plating solution circulation port 100 b located below the anode chamber 110. At the bottom of the shield box 108, a plating solution circulation port 108a is formed at a position corresponding to the second plating solution flow port 100b. The plating solution dispersion chamber 104 communicates with the anode chamber 110 through the second plating solution circulation port 100b and the plating solution circulation port 108a.

  When the substrate W is held by the substrate holder 18, the peripheral portion of the substrate W is sealed in a watertight manner by the seal members 66 and 68, and the surface (surface to be plated) of the substrate W is exposed. The substrate W held by the substrate holder 18 is immersed vertically in the plating solution in the cathode chamber 112 and arranged vertically.

  As a plating solution, in this example, in addition to sulfuric acid, copper sulfate and halogen ions, a plating accelerator made of SPS (bis (3-sulfopropyl) disulfide), an inhibitor made of PEG (polyethylene glycol), and PEI (polyethylene) An acidic copper sulfate plating solution containing an organic additive of leveler (smoothing agent) made of (imine) is used. Chlorine is preferably used as the halogen ion.

  On the outer periphery of the plating tank 38, an overflow tank 36 for receiving the plating solution overflowing from the edge of the plating tank 38 is provided. One end of a circulation line 122 provided with a pump 120 is connected to the bottom of the overflow tank 36, and the other end of the circulation line 122 is connected to the bottom of the plating solution dispersion chamber 104. The plating solution accumulated in the overflow tank 36 is introduced into the plating solution dispersion chamber 104 of the plating tank 38 as the pump 120 is driven. A gap is provided between the lower end of the shielding plate 106 and the bottom surface of the plating solution dispersion chamber 104. Therefore, the flow of the plating solution flowing out from the circulation line 122 is divided into a flow toward the anode chamber 110 and a flow toward the cathode chamber 112 by the shielding plate 106. The plating solution passes through the first plating solution flow port 100a of the bottom plate 100, passes through the second plating solution flow port 100b of the bottom plate 100, and the plating solution flow port 108a of the shield box 108, and passes through the anode chamber. Flows into 110.

  The plating solution flowing into the cathode chamber 112 overflows from the edge of the plating tank 38 and flows into the overflow tank 36. Further, the plating solution flowing into the anode chamber 110 overflows from the shield box 108 through an opening (not shown) provided on the upper side surface of the shield box 108 and flows into the overflow tank 36. At this time, the plating solution in the anode chamber 110 does not substantially flow directly into the cathode chamber 112.

  The circulation line 122 is located on the downstream side of the pump 120, and a constant temperature unit 124 that adjusts the temperature of the plating solution to a predetermined temperature (for example, 25 ° C.), and foreign matter in the plating solution (for example, foreign matter of 0.1 μm or more) ) Is removed. A drain line 128 is connected to the bottom of the plating tank 38.

  Inside the anode chamber 110, a dissolvable anode (hereinafter referred to as a phosphorous copper anode) 130 made of a disc-shaped phosphorous copper having a size substantially the same as that of the substrate W is held by an anode holder 132 and installed vertically. ing. The phosphorous copper anode 130 is immersed in the plating solution in the anode chamber 110 when the plating bath 38 is filled with the plating solution. The substrate W held by the substrate holder 18 is immersed in the plating solution in the cathode chamber 112. The substrate W is disposed in the cathode chamber 112 so as to face the phosphorous copper anode 130.

  In this example, a material (phosphorous copper) having a copper purity of 99.69 mass% and a phosphorus concentration of 2660 mass ppm (hereinafter simply indicated by ppm) is used as the phosphorous copper anode 130. The phosphorus concentration of the phosphorous-containing copper anode 130 is 1800 to 2700 ppm, preferably 2000 to 2700 ppm. In this example, the phosphorous copper anode 130 has a sulfur concentration of 50 ppm and a nickel concentration of 100 ppm. Moreover, the average crystal grain diameter of copper of the phosphorous-containing copper anode 130 is 35 μm in this example, preferably 15 μm to 45 μm, and more preferably 30 μm to 40 μm.

  The crystal grain size of copper is desirably not only small but uniform. If the crystal grain boundary is large, partial crystal grain dropout may occur due to selective or preferential dissolution of the crystal grain boundary. On the other hand, if the crystal grain boundary is too small, it is difficult to form a uniform crystal structure. From such a viewpoint, the average crystal grain size of copper of the phosphorous-containing copper anode 130 is preferably 15 μm to 45 μm, more preferably 30 μm to 40 μm.

  Thus, by using the phosphorus-containing copper anode 130 made of phosphorus-containing copper having a phosphorus concentration of 1800-2700 ppm, preferably 2000-2700 ppm, a film having a uniform black film on the surface of the phosphorus-containing copper anode 130 is used. It has been confirmed by experiments that it is thick and it is hard to peel off.

In the experiment, the phosphorous copper anode 130 having the above components was used, and two types of plating solutions (first plating solution and second plating solution) having different additives were used as plating solutions. A black film was formed on the anode surface by performing blank electrolysis at a cathode current density of 2 ASD (A / cm ² ) for 1 hour, and plating was performed at a cathode current density of 3 ASD for 2 hours. Thereafter, shower rinsing (3.5 L / min) was performed vertically on the black film formed on the anode surface from a distance of 30 cm. During this shower rinsing, a black film was photographed every 10 seconds to examine the state of the black film. As a result, the base (anode) was not exposed even after 90 seconds of rinsing regardless of the type of plating solution, and the black film did not peel off from the base (anode).

  In contrast, a phosphorous copper anode having a phosphorus concentration of 400 to 500 ppm was used, and a comparative experiment was performed in the same manner as described above. As a result of this comparative experiment, the base (anode) is exposed after rinsing for 30 seconds in the case of the first plating solution and after 20 seconds in the case of the second plating solution, and the black film is peeled off from the base (anode). Was happening. Further, using a phosphorus-containing copper anode having a phosphorus concentration of 400 to 600 ppm, a comparative experiment was performed in the same manner as described above. As a result of this comparative experiment, the base (anode) was exposed after rinsing for 10 seconds in the case of the first plating solution and after 20 seconds in the case of the second plating solution, and the black film was peeled off from the base (anode). Was happening.

  An adjustment plate (regulation plate) 134 for adjusting the potential distribution in the plating tank 38 is disposed inside the plating tank 38. The adjusting plate 134 is located between the phosphorous copper anode 130 and the substrate holder 18 disposed in the plating tank 38. In this example, the adjustment plate 134 includes a cylindrical portion 136 and a rectangular flange portion 138, and an opening 134 a is formed on the inner peripheral surface of the cylindrical portion 136. As the material of the adjustment plate 134, vinyl chloride, which is a dielectric, is used. The size of the opening 134a, that is, the diameter of the inner peripheral surface of the cylindrical portion 136 is set so as to sufficiently limit the expansion of the electric field. The cylindrical portion 136 has a predetermined length along its axis.

  The shield box 108 has an opening 108 b at a position corresponding to the cylindrical portion 136 of the adjustment plate 134. The flange portion 138 of the adjustment plate 134 is located in the anode chamber 110, and the cylindrical portion 136 of the adjustment plate 134 is fitted in the opening 108b. The anode side end of the cylindrical portion 136 is located in the anode chamber 110. A diaphragm 142 is fixed to the anode side end portion by an annular fixing plate 140. The diaphragm 142 is disposed so as to cover the inner peripheral surface of the cylindrical portion 136, that is, the entire opening portion 134 a of the adjustment plate 134. This diaphragm 142 is comprised from the cation exchange membrane which does not let an additive pass through a metal ion, or a porous membrane. An example of such a porous membrane is Yumicron (trade name) manufactured by Yuasa Membrane Co., Ltd.

  A gap between the flange portion 138 and the inner peripheral surface of the shield box 108, a gap between the flange portion 138 and the diaphragm 142, and a gap between the fixing plate 140 and the diaphragm 142 are respectively sealed by seal members (not shown). .

In the anode chamber 110, a net-like water-permeable anode bag 144 surrounding the phosphorous copper anode 130 is fixed to the plating tank 38. As the anode bag 144, for example, a polypropylene mesh having a thread-to-thread spacing of 40 μm to 50 μm and a copper sulfate plating solution flow rate of 20 mL / cm ² / sec, a thread-to-thread spacing of 10 μm to 15 μm. And a polypropylene mesh having a water flow rate of the copper sulfate plating solution of 1.25 mL / cm ² / sec, or a 1 μm gap between the yarn and the thread, and a water flow rate of the copper sulfate plating solution of 0.6 mL / cm ² / A sec mesh made of polypropylene is used. The upper end of the anode bag 144 extends to a position higher than the opening that overflows the plating solution in the anode chamber 110.

  According to the present embodiment, the periphery of the phosphorous copper anode 130 is covered with a net-like anode bag 144 having water permeability, and the entire anode side end of the opening 134 a of the adjustment plate 134 is covered with the diaphragm 142. Yes. With this configuration, the black film does not enter the cathode chamber 112 even if the black film is peeled off from the phosphorous copper anode 130. Therefore, it is possible to almost completely prevent the black film from adhering to the surface of the substrate W.

  That is, when the black film is peeled off from the phosphorous-containing copper anode 130, the black film floats in the plating solution in the anode chamber 110. The movement of the black film to the cathode chamber 112 is caused by the anode bag 144 and the diaphragm 142. Can be double blocked. The plating solution in the anode chamber 110 including the floating black film is transferred to the filter 126 through the overflow tank 36, and contaminants including the black film are removed by the filter 126. Thereafter, the plating solution again flows into the cathode chamber 112 and the anode chamber 110.

Furthermore, in this example, a bubbling mechanism 150 is provided that supplies gas such as air or an inert gas (for example, N ₂ gas) to the plating solution in the anode bag 144 to form bubbles in the plating solution. The bubbling mechanism 150 includes a bubbling pipe 152 having a large number of jet ports on the upper surface and a gas supply line 154 communicating with the bubbling pipe 152. The bubbling piping 152 extends horizontally along the surface of the phosphorous copper anode 130 and is disposed in the anode bag 144. The gas supply line 154 is provided with a filter 156 for removing foreign substances from the gas passing through the gas supply line 154.

The bubbling mechanism 150 is provided as necessary. By supplying a gas such as air or an inert gas (for example, N ₂ gas) into the plating solution present on the surface of the phosphorous copper anode 130 in the anode bag 144 by the bubbling mechanism 150, bubbles are formed, The black film can be made more difficult to peel from the phosphorous-containing copper anode 130.

  Inside the cathode chamber 112 of the plating tank 38, a stirring paddle 232 is disposed as a stirring tool for stirring the plating solution between the substrate holder 18 and the adjusting plate 134. The stirring paddle 232 is located between the substrate holder 18 and the adjustment plate 134 disposed in the plating tank 38, and extends in the vertical direction. During plating of the substrate W, the stirring paddle 232 reciprocates in parallel with the substrate W to stir the plating solution, so that sufficient copper ions can be uniformly supplied to the surface of the substrate W.

As shown in FIGS. 7 and 8, the stirring paddle 232 is composed of a rectangular plate member having a constant thickness t of 3 mm to 5 mm. The stirring paddle 232 is configured to have a plurality of lattice portions 232b extending in the vertical direction by providing a plurality of elongated holes 232a in parallel with each other. The material of the agitation paddle 232 is, for example, a resin such as PVC, PP, or PTFE, or SUS or titanium covered with a fluororesin, and it is desirable that at least a portion in contact with the plating solution is in an electrically insulating state. Longitudinal dimension L ₂ of the vertical length L ₁ and the long hole 232a of the mixing paddle 232 is set to be sufficiently larger than the size in the vertical direction of the substrate W. The horizontal dimension H of the stirring paddle 232 is such that the sum of the amplitude (stroke) of the reciprocating motion of the stirring paddle 232 and the horizontal dimension H of the stirring paddle 232 is sufficiently larger than the horizontal dimension of the substrate W. It is set to be large.

  The width and number of the elongated holes 232a are required so that the lattice portion 232b between the elongated holes 232a and the elongated holes 232a efficiently stirs the plating solution, and the plating solution efficiently passes through the elongated holes 232a. It is preferable to determine the lattice portion 232b to be as thin as possible within a range having rigidity.

  The copper plating unit 34 is provided with a plating power source in which a positive electrode is connected to the phosphorous copper anode 130 via a conductive wire and a negative electrode is connected to the surface of the substrate W via a conductive wire during plating.

Next, a series of processes for performing electrolytic copper plating on the surface of the substrate W using the electrolytic copper plating apparatus shown in FIG. 1 will be described.
When the apparatus is started up, a blank film is generated on the surface of the phosphorous copper anode 130 by performing air electrolysis in which a voltage is applied between the dummy substrate and the phosphorous copper anode 130. In this empty electrolysis, as described above, a phosphorous-containing copper anode made of phosphorous-containing copper having a phosphorus concentration of 1800 to 2700 ppm, preferably 2000 to 2700 ppm, and an average crystal grain size of 15 μm to 45 μm, preferably 30 μm to 40 μm. By using 130, a black film is formed on the surface of the phosphorous-containing copper anode 130 with a uniform film thickness and hardly peeled off.

  Then, one substrate is taken out from the cassette 10 mounted on the cassette table 12 by the substrate transfer device 22 and placed on the aligner 14 so that the positions of the orientation flat and the notch are aligned in a predetermined direction. The substrate whose direction is adjusted by the aligner 14 is transferred to the substrate attaching / detaching unit 20 by the substrate transfer device 22.

  Two substrate holders 18 housed in the stocker 24 are simultaneously held by the first transporter 42 and conveyed to the substrate attaching / detaching unit 20. Then, the substrate holder 18 is lowered in a horizontal state, whereby the two substrate holders 18 are simultaneously placed on the placement plate 52 of the substrate attaching / detaching portion 20, and the two air cylinders are operated to perform 2 The second holding member 58 of the base substrate holder 18 is left open.

  In this state, the substrate transported by the substrate transport device 22 is inserted into the substrate holder 18 located on the center side, and the air cylinder is reversely operated to close the second holding member 58. Thereafter, the second holding member 58 is locked by a lock / unlock mechanism (not shown). Then, after the mounting of the substrate on one substrate holder 18 is completed, the mounting plate 52 is slid in the horizontal direction, and the substrate is mounted on the other substrate holder 18 in the same manner. Thereafter, the mounting plate 52 is returned to the original position.

  The substrate W is fixed to the substrate holder 18 with the surface to be plated exposed from the opening of the substrate holder 18. The gap between the outer peripheral portion of the substrate W and the second holding member 58 is sealed by the substrate side sealing member 66 so that the plating solution does not enter the internal space of the substrate holder 18, and the first holding member 54 and the second holding member 58. Is sealed with a holder-side seal member 68. The substrate W is electrically connected to the plurality of electrical contacts 88 at a portion not touching the plating solution. A wiring is connected from the electrical contact 88 to the connection terminal 91 of the substrate holder 18, and power can be supplied to a conductive layer such as a seed layer of the substrate by connecting a power source to the connection terminal 91. The substrate attaching / detaching unit 20 has a sensor for confirming a contact state between the substrate W held by the substrate holder 18 and the electrical contact 88. When the sensor determines that the contact state between the substrate W and the electrical contact 88 is defective, the sensor inputs a signal to a controller (not shown).

  The substrate holder 18 holding the substrate is conveyed from the substrate attaching / detaching unit 20 to the pre-wet tank 26 by the first transporter 42 of the substrate holder conveying device 40. The first transporter 42 lowers the substrate holder 18, thereby immersing the substrate together with the substrate holder 18 in the prewetting liquid in the prewetting tank 26.

  Next, the substrate holder 18 holding the substrate is transferred from the pre-wet tank 26 to the pre-soak tank 28 by the first transporter 42. In the pre-soak bath 28, the oxide film on the substrate surface is etched to expose a clean metal surface. Further, the substrate holder 18 holding the substrate is conveyed by the first transporter 42 to the first cleaning tank 30a. In the first cleaning tank 30a, the substrate and the substrate holder 18 are cleaned by the cleaning liquid supplied to the inside. As the cleaning liquid, pure water, chemical liquid, or the like can be used.

  The substrate holder 18 holding the cleaned substrate is transferred from the first cleaning tank 30a to the copper plating unit 34 by the second transporter 44 of the substrate holder transfer device 40. The substrate holder 18 is lowered in the plating tank 38 by the second transporter 44 and is suspended from the upper part of the plating tank 38. The second transporter 44 of the substrate holder transport device 40 sequentially repeats the above operations to sequentially transport the substrate holder 18 with the substrate mounted thereon to the plating tank 38 of the copper plating unit 34.

  After the holding of all the substrate holders 18 is completed, the plating voltage between the phosphorous copper anode 130 and the substrate W in the plating tank 38 is circulated and overflowed while the plating solution in the plating tank 38 is circulated and overflowed. Is applied, the surface of the substrate W is plated with copper. The substrate holder 18 is suspended and fixed at an upper portion of the plating tank 38 via a holder hanger 90, and power is supplied from a plating power source to a conductive layer such as a seed layer through a conductor 86 and an electrical contact 88. During plating of the substrate W, the paddle driving device 46 reciprocates the stirring paddle 232 in parallel with the surface of the substrate, and further, if necessary, bubbles are formed in the plating solution by the bubbling mechanism 150.

  During the copper plating, even if the black film is peeled off from the surface of the phosphorous-containing copper anode 130 and this black film floats in the plating solution in the anode chamber 110, the movement of the black film into the cathode chamber 112 does not occur in the anode bag. 144 and the membrane 142 are doubly blocked, thereby preventing the black film from adhering to the surface of the substrate W almost completely.

  After the copper plating is completed, the application of the plating voltage, the supply of the plating solution, the paddle reciprocation and the bubbling are stopped, and the two substrate holders 18 holding the substrate W are simultaneously held by the second transporter 44, and the same as described above. Then, the substrate W is conveyed to the second cleaning tank 30b, and the surface of the substrate W is cleaned with the cleaning liquid together with the substrate holder 18.

  The substrate holder 18 holding the cleaned substrate is transported from the second cleaning tank 30 b to the blow tank 32 by the second transporter 44. In the blow tank 32, the droplets adhering to the surface of the substrate W held by the substrate holder 18 are removed and dried by blowing air or nitrogen gas.

  The two substrate holders 18 dried in the blow tank 32 are transported to the substrate attaching / detaching unit 20 by the first transporter 42 and placed on the placement plate 52 of the substrate attaching / detaching unit 20. And the lock | rock of the 2nd holding member 58 of the board | substrate holder 18 located in the center side is cancelled | released by the lock / unlock mechanism, the air cylinder is operated, and the 2nd holding member 58 is opened. In this state, the substrate transfer device 22 takes out the substrate from the substrate holder 18 and carries it to the spin rinse dryer 16. The substrate is spin-dried (drained) by the high-speed rotation of the spin rinse dryer 16, and then the dried substrate is returned to the cassette 10 by the substrate transport device 22.

  Then, after the substrate held by one substrate holder 18 is returned to the cassette 10 or in parallel therewith, the placement plate 52 is slid in the lateral direction, and similarly, the other substrate holder 18 is moved to the other substrate holder 18. The held substrate is spin-dried and then returned to the cassette 10 by the substrate transfer device 22.

  FIG. 9 is a longitudinal sectional view showing another copper plating unit 34a provided in the electrolytic copper plating apparatus shown in FIG. The copper plating unit 34a of this example is different from the copper plating unit 34 shown in FIG. 6 as follows. That is, the diaphragm 142 is not provided on the adjustment plate 134 of the copper plating unit 34a of this example. Instead, the phosphorous copper anode 130 disposed in the anode chamber 110 is surrounded by a first anode bag 162 having a mesh-like water permeability attached to the anode holder 132, and the first anode bag 162 is surrounded by the plating tank 38. It is surrounded by a second anode bag 164 having a mesh-like water permeability that is fixed to the inner wall. In addition, the bubbling pipe 152 of the bubbling mechanism 150 is disposed horizontally along the surface of the anode holder 132 between the first anode bag 162 and the second anode bag 164.

  As the first anode bag 162, for example, a polypropylene mesh having a spacing between threads of 20 μm is used, and as the second anode bag 164, for example, a finer mesh than the first anode bag 162, for example, between yarn and thread. A polypropylene mesh with an interval of 1 μm is used. The first anode bag 162 is pulled out of the plating tank 38 and replaced together with the anode holder 132 when the phosphorous copper anode 130 is replaced.

  According to this example, a relatively large black film that falls off the surface of the phosphorous copper anode 130 and floats in the plating solution in the anode chamber 110 is prevented from passing through the first anode bag 162. The relatively small black film that has passed through the first anode bag 162 is prevented from passing through the second anode bag 164. In this way, the black film floating in the plating solution is almost completely prevented from entering the cathode chamber 112 from the anode chamber 110.

  FIG. 10 is a longitudinal sectional view showing still another copper plating unit 34b. The copper plating unit 34b of this example is different from the copper plating unit 34 shown in FIG. 6 as follows. That is, the copper plating unit 34b of this example is not provided with the anode bag 144. Instead, a pre-filter 170 is disposed at the second plating solution supply port 100b of the bottom plate 100 and the plating solution circulation port 108a of the shield box 108 that communicate the plating solution dispersion chamber 104 of the plating tank 38 and the inside of the shield box 108. Yes. Further, a plating solution discharge port 172 for discharging the plating solution in the anode chamber 110 is provided at the bottom of the bottom plate 100 and the shield box 108. One end of a plating solution discharge line 176 having an opening / closing valve 174 provided therein is connected to the plating solution discharge port 172, and the other end of the plating solution discharge line 176 is connected to the circulation line 122 on the upstream side of the pump 120. Has been. In the vicinity of the bottom of the shield box 108, the bubbling pipe 152 of the bubbling mechanism 150 is disposed horizontally along the back surface of the anode holder 132.

  According to this example, the plating solution from which foreign matter has been removed by the prefilter 170 flows into the anode chamber 110 into the anode chamber 110. The black film falls off the surface of the phosphorous copper anode 130 and floats on the plating solution in the anode chamber 110, but the black film gradually sinks due to its own weight. The plating solution in the anode chamber 110 containing a large amount of the black film is discharged from the bottom of the anode chamber 110 through the plating solution discharge line 176.

  The circulation line 122 is branched into a first branch line 200A and a second branch line 200B on the downstream side of the filter 126. The first branch line 200 </ b> A extends to the anode chamber 110, and the second branch line 200 </ b> B extends to the inside of the plating solution dispersion chamber 104. A pre-filter 170 is provided on the first branch line 200A, and foreign matter in the plating solution flowing through the first branch line 200A is removed by the pre-filter 170. The plating solution that has passed through the second branch line 200 </ b> B is discharged into the plating solution dispersion chamber 104.

  The plating solution containing the black film joins the circulation line 122 on the upstream side of the pump 120, and is sent to the constant temperature unit 124 and the filter 126 by the pump 120. The black film is removed from the plating solution by the filter 126. Furthermore, since the plating solution discharge line 176 for discharging the plating solution from the anode chamber 110 is separated from the second branch line 200B extending to the cathode chamber 112, it is almost completely possible that the black film enters the cathode chamber 112. Can be prevented.

  Even if the black film in the anode chamber 110 sinks due to its own weight, the prefilter 170 can prevent the black film from entering the plating solution dispersion chamber 104. Therefore, the black film does not enter the cathode chamber 112 through the plating solution dispersion chamber 104.

  Also in the example shown in FIG. 10, similarly to the example of FIG. 6, an opening may be provided on the upper side surface of the shield box 108 so that the plating solution in the anode chamber 110 flows into the overflow tank 36. Alternatively, the plating solution in the anode chamber 110 may not overflow. In this case, as shown in FIG. 10, an on-off valve 210 is provided in the first branch line 200A. The on-off valve 210 is disposed on the upstream side of the prefilter 170. The liquid supply amounts of the on-off valve 210, the on-off valve 174, and the pump 120 are controlled so that the amount of plating solution in the anode chamber 110 is maintained within a certain range.

  According to the above-described embodiment, the amount of the black film contained in the plating solution in the anode chamber 110 can be reduced, and the black film floating in the plating solution can be prevented from entering the cathode chamber 112. As the pre-filter 170, a coarser one than the diaphragm 142 is used in order to ensure appropriate liquid permeability of the plating solution. A backflow prevention valve may be used instead of the prefilter 170 to prevent the plating solution in the anode chamber 110 from flowing back into the plating solution dispersion chamber 104.

  FIG. 11 is a longitudinal sectional view showing still another copper plating unit 34c. The copper plating unit 34c of this example is different from the copper plating unit 34b shown in FIG. 10 in that the plating solution discharge line 176 extending from the plating solution discharge port 172 is not connected to the circulation line 122, and the inside of the plating solution discharge line 176 is formed. The flowing plating solution is discarded. Thereby, it is possible to prevent the black film from gradually increasing in the plating solution and causing the filters 126 and 170 to be clogged. Alternatively, small foreign matters that cannot be captured by the filter 126 can be prevented from entering the cathode chamber 112.

  FIG. 12 shows still another copper plating unit 34d. The copper plating unit 34d of this example is different from the copper plating unit 34 shown in FIG. 6 as follows. That is, the anode bag 144 is not provided in the copper plating unit 34d of this example. The bottom plate 100 is not provided with the second plating solution supply port 100b, and the shield box 108 is not provided with the plating solution flow port 108a. Instead, a plating solution supply line 182 branched from the circulation line 122 on the downstream side of the filter 126 and provided with an opening / closing valve 180 is provided, and this plating solution supply line 182 is connected to the anode chamber 110. Connected to the anode chamber 110 are a pure water supply line 184 and a plating solution discharge line 190 extending upward from the bottom of the anode chamber 110 and provided with an on-off valve 186 and a pump 188 therein. Further, a liquid level sensor 192 for detecting the liquid level of the plating solution in the anode chamber 110 is provided. Then, the bubbling pipe 152 of the bubbling mechanism 150 is horizontally disposed along the back surface of the anode holder 132 at the bottom of the shield box 108.

  In the example shown in FIG. 12, the plating solution in the anode chamber 110 does not overflow and is in a state where a certain amount is accumulated. The operation of the on-off valve 180 and the on-off valve 186 and pure water so that the liquid level of the plating solution detected by the liquid level sensor 192 (that is, the amount of the plating solution in the anode 110) is maintained within a predetermined range. The amount of pure water supplied from the supply line 184 is controlled.

  According to this example, the anode chamber is passed through the plating solution supply line 182 branched from the circulation line 122 while the plating solution liquid level in the anode chamber 110 is kept within a certain range via the liquid level sensor 192. The plating solution is supplied into 110, and pure water is supplied to the plating solution in the anode chamber 110 through the pure water supply line 184. Then, the plating solution in the anode chamber 110 is discharged from the bottom thereof to the outside through the plating solution discharge line 190.

  Even in this example, the black film floating in the plating solution in the anode chamber 110 gradually sinks downward due to its own weight. The plating solution in the anode chamber 110 containing a large amount of the black film is discharged from the anode chamber 110 through the plating solution discharge line 190. As a result, the amount of black film contained in the plating solution in the anode chamber 110 can be reduced, and the black film floating in the plating solution can be almost completely prevented from entering the cathode chamber 112.

  FIG. 13 is a longitudinal sectional view showing still another copper plating unit 34e. The copper plating unit 34e of this example is different from the copper plating unit 34d shown in FIG. 12 in that the plating solution discharge line 190 is connected to the bottom of the anode chamber 110, and the plating solution is moved in the plating solution discharge line 190 by its own weight. The point is that it flows and is discharged to the outside. The plating solution discharge line 190 is provided with an open / close valve 194. Thereby, simplification of the apparatus can be achieved.

  FIG. 14 is a longitudinal sectional view showing still another copper plating unit 34f. The copper plating unit 34f of this example is different from the copper plating unit 34 shown in FIG. 6 in that the phosphorous copper anode 130 is surrounded by the double anode bags 162 and 164 and the plating solution in the overflow tank 36. Is returned to the cathode chamber 112, but not returned to the anode chamber 110. Further, the bubbling mechanism 150 is not provided in the copper plating unit 34f.

  The two net-like anode bags are composed of a first anode bag 162 having a coarse mesh and a second anode bag 164 having a finer mesh than the first anode bag 162. The second anode bag 164 is disposed so as to surround the first anode bag 162. These anode bags 162 and 164 are made of polypropylene mesh having water permeability. Such double anode bags 162 and 164 can capture a relatively large black film and a relatively small black film in two stages, and prevent clogging of the diaphragm 142.

  The anode chamber 110 only stores the plating solution, and basically the plating solution does not overflow. A relief chute 240 is provided on the side wall of the shield box 108 constituting the anode chamber 110. The relief chute 240 communicates with the upper part of the anode chamber 110 and extends from the anode chamber 110 to the overflow tank 36. Even if the plating solution overflows the anode chamber 110, the plating solution flows into the overflow tank 36 through the relief chute 240. Therefore, the plating solution flowing out from the anode chamber 110 does not directly enter the cathode chamber 112.

  Connected to the anode chamber 110 are a pure water supply line 184 and a plating solution discharge line 190 extending downward from the bottom of the anode chamber 110. The plating solution discharge line 190 is provided with a drain valve 241. When the drain valve 241 is opened, the plating solution in the anode chamber 110 is discharged through the plating solution discharge line 190. The plating solution flowing through the plating solution discharge line 190 is discarded as it is without being collected.

  The black film floating in the plating solution in the anode chamber 110 gradually sinks downward due to its own weight. The plating solution in the anode chamber 110 containing a large amount of the black film is discharged from the anode chamber 110 through the plating solution discharge line 190 by its own weight. As a result, the amount of black film contained in the plating solution in the anode chamber 110 can be reduced, and the black film floating in the plating solution can be prevented from entering the cathode chamber 112.

  A plating solution supply line 244 is connected to the upper portion of the anode chamber 110. This plating solution supply line 244 is not for supplying the plating solution to the anode chamber 110 during the plating of the substrate, but is a so-called building bath that supplies the plating solution to the anode chamber 110 first to perform the plating process. It is only used for that purpose. The plating solution supply line 244 is provided with a first supply valve 246 and a second supply valve 247 located on the downstream side of the first supply valve 246. The circulation line 122 is connected to the plating solution supply line 244 at a branch point 249 between the first supply valve 246 and the second supply valve 247, and a part of the plating solution flowing through the plating solution supply line 244. Flows into the circulation line 122. Normally, the first supply valve 246 and the second supply valve 247 are closed. Only at the time of bathing, the first supply valve 246 and the second supply valve 247 are opened, and the plating solution is supplied to the anode chamber 110 through the plating solution supply line 244, and the cathode chamber 112 through the circulation line 122. To be supplied.

  FIG. 15 is a longitudinal sectional view showing still another copper plating unit 34g. The copper plating unit 34g of this example is different from the copper plating unit 34f shown in FIG. 14 in that the plating solution supply line 244 is not connected to the anode chamber 110 but is connected only to the circulation line 122. A connection line 250 that connects the circulation line 122 and the plating solution discharge line 190 is provided. The connection line 250 is provided with a second supply valve 247. Normally, the first supply valve 246 and the second supply valve 247 are closed. Only at the time of bathing, the first supply valve 246 and the second supply valve 247 are opened, and the plating solution is supplied into the anode chamber 110 and the cathode chamber 112 through the plating solution discharge line 190 and the circulation line 122.

  Although one embodiment of the present invention has been described so far, it is needless to say that the present invention is not limited to the above-described embodiment, and may be implemented in various forms within the scope of the technical idea.

18 Substrate holder 20 Substrate attaching / detaching part 24 Stocker 26 Pre-wet tank 28 Pre-soak tank 30a, 30b Cleaning tank 32 Blow tank 34 Copper plating unit 36 Overflow tank 38 Plating tank 40 Substrate holder transport device 54 First holding member (fixed holding member)
58 Second holding member (movable holding member)
62 Seal holder 66 Substrate side seal member 68 Holder side seal member 74 Clamper 100 Bottom plate 104 Plating solution dispersion chamber 108 Shield box 108b Opening portion 110 Anode chamber 112 Cathode chamber 122 Circulation line 130 Phosphorus copper anode 134 Adjustment plate 134a Opening portion 136 Tube Part 142 Diaphragm 144, 162, 164 Anode bag 150 Bubbling mechanism 170 Pre-filter 172 Plating solution outlet 176, 190 Plating solution discharge line 182 Plating solution supply line 184 Pure water supply line 192 Liquid sensor 232 Stir paddle 240 Relief chute 244 Plating solution supply line 246 First supply valve 247 Second supply valve 250 Connection line

Claims (12)

A plating tank for holding a plating solution inside,
A soluble anode made of phosphorous copper immersed in a plating solution inside the plating tank;
A substrate holder for holding the substrate and placing the substrate at a position facing the anode while immersing the substrate in a plating solution inside the plating tank;
A substrate holder transfer device for transferring the substrate holder holding the substrate;
A net-like anode bag surrounding the anode;
An adjustment plate that has an opening and is arranged between the anode and the substrate held by the substrate holder to adjust the electric field;
A diaphragm that is disposed so as to close the opening of the adjustment plate, and that allows the permeation of metal ions and prevents the permeation of additives;
The phosphorus concentration of the phosphorous copper is 2000 to 2700 mass ppm, and the average crystal grain size of copper is 15 μm to 45 μm.   2. The electrolytic copper plating apparatus according to claim 1, wherein an average crystal grain size of the phosphorous copper is 30 μm to 40 μm. A shielding box that divides the inside of the plating tank into an anode chamber in which the anode is disposed and a cathode chamber in which the substrate held by the substrate holder is disposed;
The anode bag and the diaphragm are disposed in the anode chamber,
2. The electrolytic copper plating apparatus according to claim 1, wherein the shield box has an opening that is closed by the diaphragm at a position facing the opening of the adjustment plate.   The electrolytic copper plating apparatus according to claim 3, further comprising a bubbling mechanism that forms bubbles in the plating solution in the anode chamber.   The electrolytic copper plating apparatus according to any one of claims 1 to 4, wherein the diaphragm is made of a cation exchange membrane or a porous membrane. A plating tank for holding a plating solution inside,
A soluble anode made of phosphorous copper immersed in a plating solution inside the plating tank;
A substrate holder for holding the substrate and placing the substrate at a position facing the anode while immersing the substrate in a plating solution inside the plating tank;
A substrate holder transfer device for transferring the substrate holder holding the substrate;
A net-like first anode bag surrounding the anode;
A second anode bag surrounding the first anode bag and having a finer mesh shape than the first anode bag;
An adjustment plate that has an opening and is arranged between the anode and the substrate held by the substrate holder to adjust the electric field;
The phosphorus concentration of the phosphorous copper is 2000 to 2700 mass ppm, and the average crystal grain size of copper is 15 μm to 45 μm. A shielding box that divides the inside of the plating tank into an anode chamber in which the anode is disposed and a cathode chamber in which the substrate held by the substrate holder is disposed;
The first anode bag and the second anode bag are disposed in the anode chamber;
The electrolytic copper plating apparatus according to claim 6, wherein the shield box has an opening that is closed by a diaphragm at a position facing the opening of the adjustment plate.   The electrolytic copper plating apparatus according to claim 7, further comprising a bubbling mechanism that forms bubbles in the plating solution in the anode chamber.   The electrolytic copper plating apparatus according to claim 7 or 8, wherein the diaphragm is made of a cation exchange membrane or a porous membrane. A plating tank for holding a plating solution inside,
A soluble anode made of phosphorous copper immersed in a plating solution inside the plating tank;
A substrate holder for holding the substrate and placing the substrate at a position facing the anode while immersing the substrate in a plating solution inside the plating tank;
A substrate holder transfer device for transferring the substrate holder holding the substrate;
An adjustment plate that has an opening and is arranged between the anode and the substrate held by the substrate holder to adjust the electric field;
A diaphragm disposed so as to close the opening of the adjusting plate, and allows the permeation of metal ions and prevents the permeation of additives;
The inside of the plating tank is divided into an anode chamber in which the anode and the diaphragm are disposed and a cathode chamber in which a substrate held by the substrate holder is disposed, and the position facing the opening of the adjustment plate is A shield box provided with an opening blocked by a diaphragm;
A plating solution discharge line for extracting and discharging the plating solution in the anode chamber from the bottom of the anode chamber;
The phosphorus concentration of the phosphorous copper is 2000 to 2700 mass ppm, and the average crystal grain size of copper is 15 μm to 45 μm.   The electrolytic copper plating apparatus according to claim 10, wherein the diaphragm is made of a cation exchange membrane or a porous membrane.   The electrolytic copper plating apparatus according to claim 10 or 11, further comprising a bubbling mechanism that forms bubbles in the plating solution in the anode chamber.

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