JP5184308B2 - Plating apparatus and plating method - Google Patents

Description

  The present invention relates to a plating apparatus and a plating method for plating on the surface of an object to be plated (substrate) such as a semiconductor wafer, and in particular, a plating film on fine wiring grooves and holes provided on the surface of a semiconductor wafer and a resist opening. And a plating apparatus and a plating method suitable for forming bumps (protruding electrodes) that are electrically connected to package electrodes and the like on the surface of a semiconductor wafer.

  For example, in TAB (Tape Automated Bonding) and flip chip, a protruding connection electrode in which gold, copper, solder, or nickel is laminated in a multilayer on a predetermined portion (electrode) on the surface of a semiconductor chip on which wiring is formed. It is widely performed to form (bump) and electrically connect to the electrode of the package and the TAB electrode through the bump. There are various bump forming methods such as electroplating, vapor deposition, printing, and ball bumping. However, as the number of I / O of semiconductor chips increases and the pitch becomes finer, the bumps can be made finer and the performance is improved. An electroplating method in which is relatively stable is often used.

  According to the electroplating method, a high-purity metal film (plating film) can be easily obtained, and not only the deposition rate of the metal film is relatively high, but also the thickness of the metal film can be controlled relatively easily. Can do. Further, in the formation of a metal film on a semiconductor wafer, in-plane uniformity of film thickness is strictly required in order to pursue high-density mounting, high performance, and high yield. According to electroplating, it is expected that a metal film having excellent in-plane film thickness uniformity can be obtained by making the metal ion supply rate distribution and potential distribution of the plating solution uniform.

  As a plating apparatus that employs a so-called dip method, a substrate (a body to be plated) having a plating tank holding a plating solution therein, and holding the periphery of the substrate holder in a watertight manner inside the plating tank; Arrange the adjustment plate (regulation plate) made of a dielectric with a central hole formed in the center so that the anode held by the anode holder is opposed to each other and vertically positioned between the anode and the substrate, Further, there is known one in which a paddle for stirring the plating solution is disposed between the adjustment plate and the substrate (see, for example, Patent Document 1).

  According to the plating apparatus described in Patent Document 1, the plating solution is accommodated in the plating tank, and the anode, the substrate, and the adjustment plate are immersed in the plating solution, and at the same time, the anode is used as the anode of the plating power source through the conductive wire. By connecting the substrate to the cathode of the plating power source and applying a predetermined plating voltage between the anode and the substrate, the metal is deposited on the surface of the substrate to form a metal film (plating film). During plating, the plating solution is stirred by a paddle placed between the adjustment plate and the substrate, so that a sufficient amount of ions are uniformly supplied to the substrate to form a metal film with a more uniform thickness. Like to do.

  In the invention described in Patent Document 1, an adjustment plate having a plating solution flow path is disposed inside a cylindrical body between an anode and a substrate disposed at a position facing the anode, and plating is performed using this adjustment plate. By adjusting the potential distribution in the tank, the thickness distribution of the metal film formed on the surface of the substrate is adjusted.

  In addition, the distance between the adjustment plate placed in the plating solution in the plating tank and the object to be plated (the object to be plated) should be shortened as much as possible, and the potential distribution over the entire surface of the object to be plated should be made more uniform. Thus, there has been proposed a plating apparatus that forms a metal film having a more uniform thickness (see, for example, Patent Document 2).

  In recent years, there has been a strong demand for shortening the plating time required to form a plating film having a predetermined film thickness to about 2/3 of the conventional one in order to realize higher device productivity. In order to perform plating with a predetermined film thickness in a shorter time on a certain plating area, it is necessary to apply a high current and perform plating at a high plating rate, that is, to perform plating at a high current density. . However, when plating is performed under conditions of high current density with a conventional general plating apparatus and its operation method, the in-plane uniformity of the plating film thickness tends to deteriorate. The in-plane uniformity of the plating film thickness is required to be higher than ever before. For this reason, as described in Patent Document 2, it is more important to reduce the distance between the adjustment plate and the object to be plated when plating is performed under plating conditions having a high current density.

  As a problem of performing plating under the condition of high current density, when the inventor performs plating under the condition of high current density with a conventional general plating apparatus and its operation method, the bump formed by plating has a tip shape. Have found that they tend to be convex rather than flat. In the WL-CSP (Wafer Level-Chip Size Package), which is currently under development, bumps are formed by plating, and then the bumps are covered with resin, but the tips of the bumps have a convex shape. In order to cover the entire bump, an extra resin must be deposited, which leads to an increase in cost. Furthermore, the surface of the resin is smoothed with a spatula called a squeegee in order to smooth the surface when the resin is piled up, but if there are bumps that are partially convex and raised, the resin with the spatula (squeegee) There is also a problem that bumps are knocked down when leveling the surface. Also, after the bumps were coated with resin, the resin and bumps were scraped to the specified thickness by mechanical polishing, but at this time, too much resin had to be scraped off as much as possible, increasing costs. Connected.

A plating apparatus and a plating for plating a printed wiring board having a through hole by driving a pair of stirring rods for stirring a plating solution, one at 5 cm / sec to 20 cm / sec and the other at 25 cm / sec to 70 cm / sec A method has been proposed (see, for example, Patent Document 3). However, even if plating is performed while moving the pair of stirring rods at such a speed, a flat tip-shaped bump cannot be formed.
JP WO2004 / 009879 pamphlet JP 2001-329400 A JP 2006-41172 A

  The present invention has been made in view of the above points, and when plating is performed on an object to be plated (substrate) such as a semiconductor wafer, a flat tip-shaped bump is formed even under a high current density condition. Another object of the present invention is to provide a plating apparatus and a plating method capable of forming a metal film having good in-plane uniformity.

The invention according to claim 1 is a plating tank for holding a plating solution, an anode disposed by being immersed in a plating solution in the plating tank, a holder for holding a substrate and disposed at a position facing the anode. , a plate-like member having a plurality of grating portions, wherein disposed between the anode and the substrate held by the holder, a paddle for stirring the plating solution in parallel to reciprocate with said substrate, a dielectric An adjustment plate that is disposed between the anode and the paddle to make the potential distribution uniform over the entire surface of the substrate, and a control unit that controls a paddle driving unit that drives the paddle, , the average of the absolute value of the moving speed of the paddle Ri do the 70~100cm / sec, and the position of the grating portion of the paddle at the stroke end of the left and right of the paddle is moved do not overlap each other A plating apparatus and controls the paddle drive portion.

Thus, for example, bumps are formed by moving the paddle disposed between the anode and the substrate at a speed (high speed) such that the average of the absolute values is 70 to 100 cm / sec and stirring the plating solution. In this case, sufficient and uniform ions are supplied into a resist hole formed in advance to form a bump, and a flat tip-shaped bump can be formed even under high current density plating conditions.

The invention described in 請 Motomeko 2, the plate-like member is a plating apparatus according to claim 1, characterized in that it has a constant thickness of 3 to 5 mm.

A third aspect of the present invention is the plating apparatus according to the first or second aspect, wherein the distance between the paddle and the substrate is 5 to 11 mm.

According to a fourth aspect of the invention, the pre-Symbol adjusting plate, a cylindrical portion having a shape among along the outer shape of the substrate, and wherein connected to the outer periphery of the anode side end portion of the cylindrical portion anode The plating apparatus according to any one of claims 1 to 3 , further comprising a flange portion that blocks an electric field formed between the substrate and the substrate .

In this way, by arranging the adjusting plate between the anode and the paddle and making the potential distribution over the entire surface of the substrate more uniform, the metal film (plating) formed on the substrate even under high current density plating conditions. The in-plane uniformity of the film can be improved.

A fifth aspect of the present invention is the plating apparatus according to the fourth aspect, wherein the distance between the end of the cylindrical portion on the substrate side and the substrate is 8 to 25 mm.
The distance between the end of the cylindrical portion on the substrate side and the substrate is preferably 12 to 18 mm.

According to a sixth aspect of the present invention, the holder includes a holder arm that protrudes outward, and the plating tank includes a holder support portion that contacts the holder arm and supports the holder in a suspended manner. in the sections which come into contact with the holder support, the plating apparatus according to any one of claims 1 to 5, characterized in that fixing means for fixing the holder arm to the holder supporting portion is provided is there.

  This prevents the holder from shaking or tilting when the holder is suspended and supported in the plating tank, even if the holder receives backward pressure due to the flow of the plating solution when the paddle is moved at high speed. can do.

A seventh aspect of the present invention is the plating apparatus according to the sixth aspect, wherein the fixing means comprises a magnet provided on at least one of the holder arm and the holder support portion.
Thereby, holding power can be raised with magnetic force.

The invention described in claim 8 has at least a part of a contact portion between the holder arm and the holder support portion having a contact point that contacts and closes when the holder is suspended and supported in the plating tank, The plating apparatus according to claim 6 or 7 , wherein power is supplied to the substrate by closing the contact.
As described above, when the holder is suspended and supported in the plating tank by providing a contact point on at least a part of the contact part between the holder arm and the holder support part, the contact on the holder arm side and the contact on the holder support part side Can be reliably contacted.
The invention according to claim 9 is characterized in that the adjustment plate has an opening, and the anode side of the opening is entirely covered with a partition wall that does not allow the additive to pass through metal ions. It is a plating apparatus as described in any one of 1 thru | or 8.

According to a tenth aspect of the present invention, an anode and a substrate are placed facing each other in a plating solution in a plating tank, and a paddle made of a plate-like member having a plurality of lattice portions is held by the anode and the holder. An adjusting plate, which is disposed between the anode and the paddle, is disposed between the anode and the substrate, and is arranged between the anode and the paddle . while applying a voltage between, the paddle, at a moving speed average is 70~100cm / sec of absolute value, and heavy each other position of the grating portion of the paddle at the stroke end of the left and right of the paddle is moved The plating method is characterized by reciprocally moving in parallel with the substrate so as not to become a problem .

The invention described in 請 Motomeko 11, the plate-like member is a plating method according to claim 10, characterized in that it has a constant thickness of 3 to 5 mm.

A twelfth aspect of the present invention is the plating method according to the tenth or eleventh aspect, wherein a distance between the paddle and the substrate is 5 to 11 mm.

According to a thirteenth aspect of the present invention, the adjustment plate is connected to an outer periphery of an end portion on the anode side of the cylindrical portion, the cylindrical portion having an inner shape along the outer shape of the substrate , and the anode and the a plating method according to any one of claims 10 to 12, characterized in that to have a flange portion for interrupting an electric field formed between the substrates.

The invention according to claim 14 is the plating method according to claim 13 , wherein the distance between the end of the cylindrical portion on the substrate side and the substrate is 8 to 25 mm.
The distance between the end of the cylindrical portion on the substrate side and the substrate is preferably 12 to 18 mm.

The plating apparatus includes a plating tank that holds a plating solution, an anode that is immersed in the plating solution in the plating tank, a holder that holds a substrate and is disposed at a position facing the anode, the anode, and the anode It is disposed between the substrate held by the holder, and paddle for stirring the plating solution in parallel to reciprocate with said substrate, a control unit for controlling the paddle driving unit for driving the paddle, the plating tank The upper part is separated into an upper substrate processing chamber and a lower plating solution dispersion chamber by a separating plate having a large number of plating solution passage holes therein, and an electric field is applied to the plating solution dispersion chamber while ensuring a dispersed flow of the plating solution. A shielding plate for blocking may be arranged .

As described above, the plating tank is separated into the upper substrate processing chamber and the lower plating solution dispersion chamber by the separation plate, and the shielding plate is provided in the plating solution dispersion chamber so that the electric field bypasses the plating solution dispersion chamber and serves as the anode. By suppressing the formation from the substrate toward the substrate , it is possible to prevent the electric field formed in the lower portion of the substrate from affecting the in-plane uniformity of the plating film. The effect of the electric field formed on the lower part of the substrate on the in-plane uniformity of the plating film was not a problem under the conventional low current density plating conditions. This is a problem because the film thickness of the portion near the bottom of the plating tank of the film suddenly increases.

Consists derivative collector, the anode and further comprising an adjusting plate disposed between the paddles, the adjusting plate includes a cylindrical portion having a shape among along the outer shape of the substrate, the cylindrical portion A flange portion that is connected to an outer periphery of the anode side end portion and blocks an electric field formed between the anode and the substrate, and an electric field shielding member that is in contact with the separation plate is provided at a lower end of the flange portion. It may be attached .

Thus, by providing the adjustment plate, the electric field formed between the anode and the substrate is controlled, and by providing the electric field shielding member between the flange portion and the separation plate, the flange portion and the separation plate can be controlled. It is possible to prevent the electric field from leaking from the gap.

Before SL plating liquid separating chamber, the separated anode side liquid dispersion chamber and the cathode side liquid dispersion chamber by the shielding plate, the plating liquid from the plating liquid supply passage to the anode side liquid dispersion chamber and the cathode side liquid dispersion chamber Preferably it is supplied.

Thus, by completely separating the plating solution dispersion chamber into the anode side liquid dispersion chamber and the cathode side solution dispersion chamber by the shielding plate, the potential line generated from the anode becomes the cathode through the plating solution in the plating solution dispersion chamber. Reaching the substrate can be reliably prevented.

Before SL paddle may be connected to the shaft extending from said paddle drive unit via a coupling.
Thereby, the paddle can be easily separated from the shaft extending from the paddle drive shaft via the coupling, and the replacement operation of the paddle can be performed more quickly and easily.

The plating apparatus includes a plating tank that holds a plating solution, an anode that is immersed in the plating solution in the plating tank, a holder that holds a substrate and is disposed at a position facing the anode, the anode, and the anode is disposed between the substrate held by the holder, and paddle for stirring the plating solution in parallel to reciprocate with said substrate, and a control unit for controlling the paddle driving unit for driving the paddle, a dielectric, wherein an adjusting plate disposed between the anode and the paddle may have a regulation plate movement mechanism for moving vertically or horizontally said adjustment plate relative to the substrate.

This improves the in-plane uniformity of the film thickness of the plating film formed on the surface of the substrate by finely adjusting the position of the adjustment plate in the vertical or horizontal direction with respect to the substrate via the adjustment plate moving mechanism. Can do. In particular, the adjustment plate may be placed in the position close to the substrate, to finely adjust the position of the vertical or horizontal direction relative to the substrate of the adjusting plate, the thickness of the plane of the plating film formed on the surface of the substrate This is important in improving uniformity.

Before SL adjusting plate moving mechanism may have a pressing member moving the adjusting plate is pressed against the adjustment plate.
The pressing member is composed of, for example, a pressing bolt, and when the pressing amount of the pressing member, for example, when a pressing bolt having a predetermined pitch is used as the pressing member, the number of rotations of the pressing bolt is managed to control the adjustment plate. The amount of movement can be easily adjusted.

The inner peripheral surface of the front Symbol plating tank, said adjustment plate may guide portion serving as a guide is provided for moving the.
Thereby, the adjustment plate can be moved in parallel with the substrate using the guide portion as a guide in a state where the distance between the adjustment plate and the substrate is constant. In addition, by using a guide portion that has a recess and can insert the outer peripheral end of the adjustment plate into the recess, it is possible to prevent the electric field from leaking from the outer periphery of the adjustment plate.

The front Symbol adjusting plate may be provided with an auxiliary adjustment plate mounting portion for mounting an auxiliary adjustment plates for field adjustment.
Thereby, an optimal electric field can be formed according to the kind of board | substrate by combining an adjustment board and an auxiliary adjustment board, without changing the installation position of an adjustment board, or replacing | exchanging.

Before SL holder may have a positioning and holding portion for positioning and holding the anode holder for holding the adjusting plate and the anode.
By installing a positioning holding member that positions and holds the substrate holder, adjustment plate, and anode holder in the plating tank, the center positions of the substrate holder, adjustment plate, and anode holder in the vertical direction of the plating tank can be easily matched. Can be made.

  According to the plating apparatus and the plating method of the present invention, when plating is performed on an object to be plated (substrate) such as a semiconductor wafer, a flat tip-shaped bump can be formed even under high current density conditions. A metal film having good in-plane uniformity can be formed.

  Embodiments of the present invention will be described below with reference to the drawings. In the following example, an example in which copper plating is performed on the surface of a substrate as an object to be plated is shown. In the following embodiments, the same or corresponding members are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1 is a longitudinal front view showing a plating apparatus according to an embodiment of the present invention. As shown in FIG. 1, the plating apparatus includes a plating tank 10 that holds a plating solution Q therein, and an overflow that catches the plating solution Q that overflows from the edge of the plating tank 10 on the upper outer periphery of the plating tank 10. A tank 12 is provided. One end of a plating solution supply path 16 provided with a pump 14 is connected to the bottom of the overflow tank 12, and the other end of the plating solution supply path 16 is connected to a plating solution supply port 18 provided at the bottom of the plating tank 10. Has been. As a result, the plating solution Q accumulated in the overflow tank 12 is refluxed into the plating tank 10 as the pump 14 is driven. A constant temperature unit 20 that adjusts the temperature of the plating solution Q and a filter 22 that filters and removes foreign matter in the plating solution are disposed in the plating solution supply path 16 on the downstream side of the pump 14. .

  The plating apparatus includes a substrate holder 24 that detachably holds a substrate (to-be-plated body) W and immerses the substrate W in a plating solution Q in the plating tank 10 in a vertical state. At a position facing the substrate W held by the substrate holder 24 in the plating tank 10 and immersed in the plating solution Q, the anode 26 is held by the anode holder 28 and immersed in the plating solution Q. Yes. In this example, phosphorous copper is used as the anode 26. The substrate W and the anode 26 are electrically connected via a plating power source 30, and a plating film (copper film) is formed on the surface of the substrate W by passing a current between the substrate W and the anode 26.

  A paddle 32 that reciprocates in parallel with the surface of the substrate W to stir the plating solution Q is disposed between the substrate W held by the substrate holder 24 and immersed in the plating solution Q and the anode 26. ing. In this way, sufficient copper ions can be supplied uniformly to the surface of the substrate W by stirring the plating solution Q with the paddle 32. The distance between the paddle 32 and the substrate W is preferably 5 to 11 mm. Furthermore, an adjustment plate (regulation plate) 34 made of a dielectric material is provided between the paddle 32 and the anode 26 to make the potential distribution over the entire surface of the substrate W more uniform.

As shown in FIGS. 2 and 3, the paddle 32 is composed of a rectangular plate-like member having a constant thickness of 3 to 5 mm, and a plurality of elongated holes 32a are provided in parallel in the vertical direction. It is configured to have a plurality of lattice portions 32b extending in the direction. The paddle 32 is made of, for example, titanium with a Teflon (registered trademark) coat. Dimension L ₂ in the length direction of the vertical length L ₁ and the long hole 32a of the paddle 32 is set to be sufficiently larger than the vertical dimension of the substrate W. The lateral length H of the paddle 32 is set so that the length combined with the amplitude (stroke St) of the reciprocating motion of the paddle 32 is sufficiently larger than the lateral dimension of the substrate W.

  The width and number of the long holes 32a are required so that the lattice portion 32b between the long holes 32a and the long holes 32a can efficiently stir the plating solution and the plating solution can efficiently pass through the long holes 32a. It is preferable to determine the lattice portion 32b to be as thin as possible within a range having rigidity. In addition, when the moving speed of the paddle 32 becomes slow near the both ends of the reciprocating motion of the paddle 32, or when the paddle 32 stops instantaneously, the shadow of the electric field on the substrate W (the influence of the electric field is not exerted or is affected). In order to reduce the influence of forming a small number of locations, it is important to make the lattice portion 32b of the paddle 32 thinner.

  In this example, as shown in FIG. 3, the long holes 32a are formed vertically so that the cross section of each lattice portion 32b is rectangular. As shown in FIG. 4A, the corners of the cross section of the lattice portion 32b may be chamfered, and as shown in FIG. 4B, the cross section of the lattice portion 32b becomes a parallelogram. In addition, the lattice portion 32b may be angled.

  The thickness (plate thickness) t of the paddle 32 is preferably 3 to 5 mm so that the adjustment plate 34 can be brought close to the substrate W, and is set to 4 mm in this example. It has been confirmed that when the thickness (plate thickness) t of the paddle 32 is 1 or 2 mm, the paddle 32 does not have sufficient strength. Further, by making the paddle 32 uniform in thickness, it is possible to prevent the plating solution from splashing and the plating solution from drastically shaking.

  FIG. 5 shows the drive mechanism of the paddle 32 together with the plating tank 10. The paddle 32 is fixed to a horizontally extending shaft 38 by a clamp 36 fixed to the upper end of the paddle 32, and the shaft 38 can be slid left and right while being held by a shaft holding portion 40. The end of the shaft 38 is connected to a paddle drive unit 42 that reciprocates the paddle 32 in the left and right directions. The paddle drive unit 42 converts the rotation of the motor 44 into a reciprocating motion of the shaft 38 by a crank mechanism (not shown). Convert. In this example, a control unit 46 that controls the moving speed of the paddle 32 by controlling the rotational speed of the motor 44 of the paddle driving unit 42 is provided. The paddle drive mechanism is not only a crank mechanism, but also a ball screw that converts the rotation of the servo motor into a linear reciprocating motion of the shaft, or a linear motor that reciprocates the shaft linearly. But it ’s okay.

  In this example, as shown in FIG. 6, the positions of the lattice portions 32b of the paddle 32 do not overlap each other at the left and right stroke ends where the paddle 32 has moved by the stroke St. Thereby, the influence that the paddle 32 forms the shadow of the electric field on the substrate W can be reduced.

Here, in this example, the paddle 32 is reciprocated at a higher speed than in the past so that the average absolute value is 70 to 100 cm / sec. This is because when the current density is set to 8 ASD, which is higher than the conventional 5 ASD (A / dm ² ), the agitation with the paddle is performed at a higher speed than the conventional, so that the bump with a flat tip shape is obtained. It is based on the fact that it was confirmed by experiment that it can be formed. That is, the average absolute value of the paddle stirring moving speed capable of forming a flat tip-shaped bump is 70 to 100 cm / sec. In this example, the rotational motion of the motor 44 is converted into the linear reciprocating motion of the paddle 32 by the crank mechanism. When the motor 44 makes one revolution, the paddle 32 reciprocates once with an amplitude (stroke St) of 10 cm. In this example, since the best bump was formed when the motor 44 was rotated at 250 rpm, the average absolute value of the optimum stirring movement speed of the paddle 32 was 83 cm / sec.

  An outline view of the adjustment plate 34 shown in FIG. 1 is shown in FIG. The adjustment plate 34 is composed of a cylindrical portion 50 and a rectangular flange portion 52, and the material is vinyl chloride which is a dielectric. The adjustment plate 34 is installed in the plating tank 10 such that the tip of the cylindrical portion 50 is on the substrate side and the flange portion 52 is on the anode side. The cylindrical part 50 has the size of the opening that can sufficiently limit the expansion of the electric field and the length along the axis. In this example, the length along the axial center of the cylindrical part 50 is 20 mm. The flange portion 52 is installed in the plating tank 10 so as to shield an electric field formed between the anode 26 and the substrate W. In FIG. 1, the distance between the cylindrical portion 50 of the adjusting plate 34 and the substrate W is preferably 8 to 25 mm, and more preferably 12 to 18 mm.

  In this example, as shown in FIG. 7, an adjustment plate 34 having a flange portion 52 attached to the end of the cylindrical portion 50 is used. However, as shown in FIG. Alternatively, the cylindrical part 50 may be extended so that a part 50a of the cylindrical part 50 protrudes to the anode side.

  As shown in FIG. 1, the substrate W is held by the substrate holder 24. The substrate holder 24 is configured to supply power to the substrate W with a base conductive film such as a copper sputtered film from the periphery of the substrate W. The conductive contact of the substrate holder 24 has a multi-contact structure, and the total contact width is set to be 60% or more with respect to the peripheral length on the substrate where contact can be made. Further, the contacts are equally distributed between the contacts.

  In this example, in order to move the paddle 32 at a high speed so that the average of the absolute values becomes 70 to 100 cm / sec, for example, the substrate holder 24 receives a backward pressure by the flow of the plating solution, and the substrate holder 24 Or the substrate holder 24 is inclined more than the original angle. If the substrate holder 24 is shaken or tilted, the potential distribution is not uniform, and the uniformity of the plating film is affected.

  As shown in FIG. 9, when the substrate holder 24 is installed in the plating tank 10, the holder holder 60 is held by the transporter (not shown) and suspended from above, and is fixed to the plating tank 10. A holder arm 64 protruding outward is hooked and held on the support portion 62.

  10 is an enlarged view of the periphery of the holder arm 64, FIG. 11 is a cross-sectional view showing a state where the holder arm 64 and the holder support portion 62 are in contact, and FIG. 12 is a right side view of FIG. As shown in FIGS. 10 to 12, an arm-side contact 66 is provided on the surface of the holder arm 64 that faces the holder support portion 62, and the arm-side contact 66 is connected to the substrate W by electric wiring (not shown). It is electrically connected to the cathode contact that feeds power. A support portion side contact 68 is provided on the surface of the holder support portion 62 facing the holder arm 64, and the support portion side contact 68 is electrically connected to an external power source (not shown). When the substrate holder 24 is suspended and supported by the plating tank 10, the arm side contact 66 and the support portion side contact 68 come into contact with each other and the contact is closed, so that the external power source and the cathode contact are electrically connected, and the cathode contact. A cathode voltage can be applied to the capacitor. Normally, the arm side contact 66 and the support part side contact 68 are installed on either the left or right holder arm 64 or the left or right holder support part 62.

  An arm side magnet 70 is provided as a fixing means on the surface of the holder arm 64 facing the holder support portion 62, and a support portion side magnet 72 as a fixing means is also provided on the surface of the holder support portion 62 facing the holder arm 64. Is provided. As the magnets 70 and 72, for example, neodymium magnets are used. Thereby, when the substrate holder 24 is suspended and supported by the plating tank 10, the arm side magnet 70 and the support portion side magnet 72 are brought into contact with each other and attracted to each other, whereby the substrate holder is interposed via the holder support portion 62 and the holder arm 64. 24 is more firmly fixed to the plating tank 10, and it is possible to prevent the substrate holder 24 from being shaken or tilted by the flow of the plating solution. Usually, the arm side magnet 70 and the support part side magnet 72 are installed on both the left and right sides of the holder arm 64 and the holder support part 62.

  The position of the substrate holder 24 with respect to the plating tank 10 is determined by the transport of the transporter. As shown in FIG. 13, the holder support 62 is provided with an opening 62a having a channel shape and a taper at the corner. The holder arm 64 of the substrate holder 24 may be guided by the opening 62a. Thus, even if the holder support portion 62 is provided with the opening (guide) 62a and the substrate holder 32 is positioned with respect to the plating tank 10, there is a slight dimensional "play" for positioning and transporting the substrate holder 24. is necessary. If the substrate holder 24 swings or tilts within the range of “play”, there is a risk that the contact between the arm side contact 66 and the support portion side contact 68 may be separated or intermittent, but in the vicinity of the contacts 66 and 68. Thus, by firmly supporting the substrate holder 24 on the plating tank 10 by the magnets 70 and 72, the contact between the arm side contact 66 and the support portion side contact 68 can be ensured. Further, wear of the contacts 66 and 68 due to rubbing between the contacts 66 and 68 can be suppressed, and durability of the contacts 66 and 68 is improved.

  One of the arm-side magnet 70 and the support portion-side magnet 72 may be a magnetic material instead of a magnet. Further, the surface of the magnet may be covered with a magnetic material to prevent damage due to contact. Furthermore, the magnet may be surrounded by a magnetic material so that the surface of the magnet is exposed, and a part of the magnetic material may protrude beyond the surface of the magnet to increase the magnetic force.

  As shown in FIG. 1, a separation plate 80 and a shielding plate 82 are installed at the bottom of the plating tank 10. The plating solution is dispersed at the bottom of the plating bath 10 so that the plating solution Q supplied from the plating solution supply port 18 provided at the bottom of the plating bath 10 flows uniformly over the entire surface of the substrate W. In this space, a separating plate 80 having a large number of plating solution passage holes is disposed horizontally, whereby the interior of the plating tank 10 is divided into an upper substrate processing chamber 84 and a lower plating solution. It is divided into a dispersion chamber 86.

  FIG. 14 shows a plan view of the separation plate 80. The separation plate 80 has substantially the same shape as the inner side of the plating tank 10, and a plating solution passage hole 80 a composed of a plurality of small holes is provided on the entire surface. The plating tank 10 is divided into a substrate processing chamber 84 and a plating solution dispersion chamber 86 by the separation plate 80, and a plurality of plating solution passage holes 80 a through which the plating solution flows are provided in the separation plate 80, so that the plating solution Q faces the substrate W. A uniform flow. If the plurality of plating solution through holes 80 a provided in the separation plate 80 have a large diameter, the electric field leaks from the anode 26 to the substrate W side through the plating solution dispersion chamber 86, thereby improving the uniformity of the plating film formed on the substrate W. In order to influence, in this example, the diameter of the plating solution through hole 80a is set to Φ2.5 mm.

  In this example, the plating solution passage hole 80a is provided on the entire surface of the separation plate 80, but it is not necessary to provide the plating solution passage hole 80a on the entire surface of the separation plate 80. For example, as shown in FIG. The plating solution passage holes 80a are distributed only on the substrate side with the arrangement position A as a boundary, and the plating solution passage holes 80a are provided only on the side opposite to the substrate (behind the anode) with the arrangement position B of the anode 26 as a boundary. Also good. By adopting the separation plate 80 shown in FIG. 15, it is possible to more effectively prevent the electric field from leaking from the anode 26 to the substrate W side through the plating solution dispersion chamber 86, and also to the rear of the anode 26. By providing 80a, it is possible to reliably remove the liquid when the plating liquid Q is discharged from the plating tank 10, in particular.

  As shown in FIG. 16, the separation plate 80 is installed horizontally so as to overlap the separation plate support portion 90 provided on the side plate 10 a of the plating tank 10, but between the separation plate 80 and the separation plate support portion 90. By providing the packing 92, the separation plate 80 can be installed in close contact with the separation plate support 90.

  Even if the separation plate 80 is provided, the electric field may leak from the anode 26 to the substrate W side through the plating solution dispersion chamber 86 and affect the uniformity of the plating film formed on the substrate W. Therefore, in this example, a shielding plate 82 extending downward in the vertical direction is attached to the lower surface of the separation plate 80. Thus, by providing the shielding plate 82, it is possible to more effectively prevent the electric field from leaking from the anode 26 to the substrate W side through the plating solution dispersion chamber 86, and the plating solution Q is contained in the plating bath 10. It is dispersed in the dispersion chamber 86 so that a uniform flow to the substrate processing chamber 84 in the plating tank 10 can be secured. That is, as shown in FIG. 17, the shielding plate 82 is attached to the lower surface of the separation plate 80 so that a gap S is formed between the shielding solution 82 and the bottom of the plating tank 10. It is done. In order to prevent electric field leakage, the gap S is preferably as small as possible.

As shown in FIG. 18, the shielding plate 82 may be brought into contact with the bottom of the plating tank 10, and a semicircular opening 82 a may be provided in the shielding plate 82 to ensure a plating solution flow path. . Even in this example, the opening 82a is preferably as small as possible in order to prevent leakage of the electric field. The shielding plate 82 is disposed on the lower surface of the separation plate 80 where the plating solution passage hole 80a does not exist, for example, the lower surface corresponding to the portion directly below the flange portion 52 of the adjustment plate 34 of the separation plate 80.
In this example, the shielding plate 82 is installed immediately above the plating solution supply port 18, but it is not always necessary to be directly above the plating solution supply port 18, and there may be a plurality of shielding plates 82.

  In the plating apparatus shown in FIG. 1, the positional relationship among the substrate W, the anode 26, the adjustment plate 34, and the paddle 32 in the plating tank 10 affects the uniformity of the plating film formed on the substrate W. In this example, the substrate W, the anode 26, and the adjustment plate 34 are arranged so that the center of the substrate W, the center of the anode 26, and the axial center of the cylindrical portion 50 of the adjustment plate 34 are substantially aligned. The distance between the anode 26 and the substrate W is 90 mm in this example, but the anode 26 can be installed in the range of the distance between the electrodes of 60 to 95 mm. In this example, the distance between the tip of the cylindrical portion 50 of the adjustment plate 34 on the side of the substrate W and the substrate W is 15 mm, and the length of the cylindrical portion 50 is 20 mm. The distance from W is 35 mm.

  In order to prevent an electric field from leaking from the gap between the separation plate 80 and the flange portion 52 at the lower end on the anode side of the flange portion 52 of the adjustment plate 34, as shown in FIG. An electric field shielding member 94 that is in elastic contact with is installed. Thereby, it is possible to prevent the electric field from leaking from the gap between the separation plate 80 and the flange portion 52. Note that the flange portion 52 itself may also serve as an electric field shielding member by bringing the lower end surface of the flange portion 52 into close contact with the upper surface of the separation plate 80.

  The adjustment plate 34 may be attached so that the distance from the substrate W can be adjusted. That is, as shown in FIG. 20, the adjustment plate fixing slit plate 96 having a plurality of slit portions 96 a extending in the vertical direction at a predetermined pitch is provided on the side plate 10 a of the plating tank 10, and the flange portion 52 of the adjustment plate 34. These side end portions may be inserted into an arbitrary slit portion 96 a of the adjustment plate fixing slit plate 96. In this case, the adjustment plate fixing slit plate 96 is attached to the plating tank side plate 10a by the long hole 96b and the fixing screw 98, so that the adjustment plate 34 can be adjusted according to the type of substrate to be processed by the plating apparatus. The distance from the substrate W can be finely adjusted to an optimum position.

  In addition, it is preferable to provide an electric field shielding member 100 made of a rubber seal in the vicinity of the adjustment plate fixing slit plate 96 of the flange portion 52, whereby the electric field passes from the anode 26 to the substrate W through the gap on the outer periphery of the flange portion 52. It can be prevented from being formed. The electric field shielding member 100 may be provided only on the anode side of the adjustment plate fixing slit plate 96.

  In the plating apparatus of the present invention, the typical dimensions of the bumps formed on the substrate are a bump diameter of 150 μm and a target plating film thickness of 110 μm. In order to form such a bump, it is desirable to use a plating solution having a copper sulfate concentration of 150 g / L or more as the plating solution. Examples of the plating solution include those containing a polymer component (inhibitor), a carrier component (accelerator), and a leveler component (inhibitor) of an organic additive in a base solution having the following composition.

Base liquid composition Copper sulfate pentahydrate _{(CuSO 4 · 5H 2 O)} : 200g / L
Sulfuric acid (H ₂ SO ₄ ): 100 g / L
Chlorine (Cl): 60 mg / L

  The current density in plating for forming a conventional general bump is 3 to 5 ASD, but the current density in plating in the embodiment of the present invention is, for example, 8 ASD. However, the plating apparatus and the plating method in the embodiment of the present invention can be applied up to 14 ASD. The current density condition in the following examples is 8 ASD unless otherwise noted.

  Next, the copper plating process in bump formation is shown in FIG. First, the substrate is immersed in pure water and pre-washed for 10 minutes, for example, and then the substrate is immersed in 5% by volume (vol.%) Sulfuric acid and pre-treated for 1 minute, for example. The substrate is washed with pure water twice, for example, for 30 seconds. For example, after the substrate is immersed in the plating solution, the non-energized state is maintained for 1 minute, and then the substrate is energized to perform copper plating on the substrate. Next, the substrate is washed with pure water, and then the substrate is dried by, for example, nitrogen blowing. After the plating process, the resist is stripped with a dedicated resist stripping solution, and then washed with water and dried.

22 and 23 show the difference in shape of bumps formed by plating when the stirring speed of the plating solution by the paddle is changed. The current density is 8 ASD. FIG. 22 shows a case where plating is performed at an average absolute value of the paddle stirring moving speed of 20 cm / sec, which is a conventional general speed. FIG. 23 shows an average absolute value of the paddle stirring moving speed of about 83 cm / sec. As shown in FIG. As shown in FIG. 22, when the high current density is as high as 8 ASD, in the bump formed at the conventional general low paddle stirring moving speed, the height h ₁ of the convex portion at the tip is 30 μm. However, as shown in FIG. 23, in the bump formed at a high paddle stirring moving speed such that the average absolute value of the paddle stirring moving speed is about 83 cm / sec, height _{h 2} it can be seen that is suppressed to 15um.

  24 to 28 are basically micrographs of bumps when bumps are formed on the surface of a substrate (wafer) using the plating apparatus shown in FIG. 1 and changing the paddle and paddle stirring moving speed. Indicates. FIG. 24 shows a case where the average absolute value of the paddle stirring moving speed is set to 40 cm / sec and plating is performed using a paddle having a thickness of 2 mm, and defects are recognized in the bumps formed on the entire surface of the substrate. . FIG. 25 shows the case where the average absolute value of the paddle stirring moving speed is set to 40 cm / sec and plating is performed using a paddle having a thickness of 4 mm. It is distorted. From FIG. 24 and FIG. 25, it can be seen that simply increasing the paddle thickness is not sufficient.

  In FIG. 26, when the average absolute value of the paddle stirring moving speed is set to 67 cm / sec and plating is performed using a paddle having a thickness of 4 mm, defects are recognized in the bumps formed on the entire surface of the substrate. In FIG. 27, when the average absolute value of the paddle stirring moving speed is set to 83 cm / sec and plating is performed using a paddle having a thickness of 4 mm, good bumps without defects are formed on the entire surface of the substrate. I know that. This is because when the paddle stirring moving speed is low, the supply of copper ions cannot catch up at high current density, resulting in a defect of the bump. When the paddle stirring moving speed is high, the copper ion is sufficiently supplied and the bump without defect. Can be formed. Similarly, when plating was performed using a paddle with a thickness of 3 mm when the average absolute value of the paddle stirring movement speed was set to 83 cm / sec under the conditions of high current density, as shown in FIG. In FIG. 2, no defects are observed in the bumps, but it can be seen that the bump corners are rounded compared to the case where the paddle thickness is 4 mm.

  29 and 30 show a case where plating is performed using a plating tank in which no shielding plate is installed under the separation plate in the plating tank (FIG. 29), and a shielding plate is installed under the separation plate in the plating tank. The distribution of bump height formed on the substrate when plating is performed using a plating tank (FIG. 30) is shown. The unit of the numerical value of the legend is (μm). As shown in FIG. 29, when there is no shielding plate, the plating film thickness is thicker in the vicinity of the substrate edge in the direction of the plating bath bottom of the substrate than in the central portion. By inserting, it can be seen that the plating film thickness is suppressed to the same extent as the central portion in the vicinity of the substrate edge in the plating tank bottom direction.

  FIG. 31 and FIG. 32 are graphs showing the in-plane uniformity of the height of bumps formed on the substrate when both the paddle stirring moving speed, the shape of the adjustment plate, and the distance between the adjustment plate and the substrate are changed. It is. 31 and 32, as shown in FIG. 33, the axes orthogonal to each other on the plane are the X axis and the Y axis. FIG. 31 shows an example in which an average absolute value of the paddle stirring moving speed is set to 20 cm / sec, a flat plate having a thickness of 5 mm without a cylindrical portion, and an adjustment plate having one opening at the center is used. This is a case where the plating is performed at a distance of 35 mm, and it can be seen that the height of the bump (plating film) tends to be W-shaped. FIG. 32 shows the case where the average absolute value of the paddle stirring moving speed is set to 83 cm / sec, the adjustment plate shown in FIG. 7 is used, and the distance between the substrate and the tip of the cylindrical portion is 15 mm. is there. In this case, it can be seen that the height of the bump (plating film) is flat compared to FIG. 31 and the in-plane uniformity is improved.

  FIG. 34 shows a plating apparatus according to another embodiment of the present invention. In the plating apparatus of this example, as the shielding plate 82, one that extends vertically downward from the lower surface of the separation plate 80 and has a lower end surface that reaches the bottom wall of the plating tank 10, is formed below the separation plate 80. The plating solution separation chamber 86 is completely separated into the anode side liquid dispersion chamber 110 and the cathode side liquid dispersion chamber 112 by the shielding plate 82. The lower end surface of the shielding plate 82 is fixed to the bottom wall of the plating tank 10 by, for example, welding.

  In the plating solution supply path 16, an original valve 114 and a flow meter 116 are installed between the constant temperature unit 20 and the filter 22. The plating solution supply path 16 is branched into two branch paths 16 a and 16 b on the downstream side of the filter 22, and each of the branch paths 16 a and 16 b is connected to the anode side liquid separation chamber 110 and the cathode side liquid separation chamber 112, respectively. ing. Valves 118a and 118b are installed in the branch paths 16a and 16b, respectively.

  In this way, the plating solution separation chamber 86 is completely separated into the anode-side liquid dispersion chamber 110 and the cathode-side liquid dispersion chamber 112 by the shielding plate 82, so that the potential lines generated from the anode 26 are generated in the plating solution separation chamber 86. The plating solution can be reliably prevented from leaking to the cathode (substrate) side, and the plating solution can be individually supplied to the anode-side liquid dispersion chamber 110 and the cathode-side solution dispersion chamber 112 through the plating solution supply path 16.

  35 and 36 show another drive mechanism of the paddle 32 together with the plating tank 10. In this example, the paddle 32 is attached to the paddle presser 120 at its upper end. The shaft 38 extending from the paddle drive unit 42 is divided into three parts, that is, left and right end shafts 38a and 38b supported by the shaft support unit 40, and an intermediate shaft 38c positioned between the end shafts 38a and 38b. The intermediate shaft 38c is inserted through the inside of the paddle presser 120 and exposed to the outside at both ends. One end of the intermediate shaft 38c and the end shaft 38a, and the other end of the intermediate shaft 38c and the end shaft 38b are connected by couplings 122a and 122b, respectively. In this example, screw type couplings are used as the couplings 122a and 122b, but any couplings such as so-called quick couplings may be used.

  Thus, for example, when it is necessary to replace the paddle 32, the paddle 32, the paddle presser 120, and the intermediate shaft 38c are plated as a set through the couplings 122a and 122b without removing the shaft holding portion 40 from the plating apparatus. The paddle 32 can be replaced easily and quickly. Moreover, when the paddle 32 is attached to the plating apparatus again, it can be attached to a predetermined position with good reproducibility. Further, when the adjustment plate 34 is removed from the plating apparatus, the adjustment plate 34 can be easily detached and reattached by once removing the paddle 32 from the plating apparatus.

  FIG. 37 shows another adjustment plate provided with an adjustment plate moving mechanism and another plating tank. The plating tank 10 in this example includes an inner tank 130 and an outer tank 132 that surrounds the inner tank 130. The adjustment plate 134 is configured by integrally connecting a grip portion 140 wider than the main body portion 138 to an upper portion of a rectangular flat plate main body portion 138 having a cylindrical portion 136. In this example, the adjustment plate moving mechanism 142 performs positioning in the left / right (horizontal) direction parallel to the substrate W of the adjustment plate 134 via the grip portion 140.

  The adjustment plate moving mechanism 142 includes an adjustment plate support portion 144 installed across the upper end opening of the plating tank 10, a pair of brackets 146 erected at the outer peripheral end of the adjustment plate support portion 144, and the brackets The left and right pressing bolts 148 that move in the horizontal direction by being screwed into the female screw provided at 146, and the left and right fixing bolts 150 that extend horizontally through the hollow holes provided in each bracket 146. The left and right pressing bolts 148 and the left and right fixing bolts 150 are opposed to the outer peripheral end surface of the gripping portion 140 when the gripping portion 140 of the adjustment plate 134 is placed on the adjustment plate support portion 144 and the adjustment plate 134 is installed at a predetermined position. Placed in. A female screw that is screwed to the left and right fixing bolt 150 is formed at a position facing the left and right fixing bolts 150 on the outer peripheral end surface of the gripping portion 140, and the left and right pressing bolts 148 abut against the outer peripheral end surface of the gripping portion 140 and As the pressing bolt 148 is tightened, the adjustment plate 134 is pressed inward.

  Thus, after the gripping portion 140 of the adjustment plate 134 is placed on the adjustment plate support portion 142 and the adjustment plate 134 is installed at a predetermined position, the left and right pressing bolts 148 are used to adjust the left and right sides parallel to the substrate W of the adjustment plate 134. The adjustment plate 134 can be fixed with the left and right fixing bolts 150 by adjusting the direction. The position for positioning the adjustment plate 134 using the left and right pressing bolts 148 and the left and right fixing bolts 150 may not be the grip portion 140 but may be another portion of the adjustment plate 134. In addition, by managing the rotation speed of the left and right pressing bolts 148 having a predetermined pitch, the amount of movement of the adjustment plate 134 in the left and right (horizontal) direction can be easily adjusted. The left and right fixing bolts 150 act as pulling bolts when used in a state where the left and right pressing bolts 148 are not in contact with the outer peripheral end face of the gripping part 140 and are not pressing the adjusting plate 134.

  In order to move the adjustment plate 134 in the left-right direction parallel to the substrate W, a gap is provided between the outer peripheral end surface of the main body 138 of the adjustment plate 134 and the inner peripheral surface of the inner tank 130 of the plating tank 10. In this example, a guide portion 152 having a channel-shaped recess 152 a that is opened inward is provided at a position facing the outer peripheral end surface of the main body 138 of the adjustment plate 134 of the inner tank 130. The outer peripheral end of the main body 138 of the adjustment plate 134 is inserted into the main body 138. Accordingly, the adjustment plate 134 can be moved in the left-right (horizontal) direction in parallel with the substrate W with the guide portion 152 as a guide in a state where the distance between the adjustment plate 134 and the substrate W is constant. In addition, it is possible to prevent the electric field from leaking from the outer periphery of the adjustment plate 134 by inserting the outer peripheral end portion of the main body 138 of the adjustment plate 134 into the recess 152 a of the guide portion 152.

Between the bottom of the recess 152a of the guide portion 152 and the outer peripheral end surface of the body portion 138 of the adjusting plate 134, as shown in FIG. 38, the mobile clearance t ₁ is provided. This movement clearance _{t 1} is, for example, a 1 to 5 mm, preferably 1 to 2 mm. For the convenience of construction, a gap t ₂ generally exists between the guide portion 152 and the inner peripheral surface of the inner tank 130. In this example, the gap t ₂ to prevent the potential line leaks from the seal retainer 154 and using the fixing bolts 156, for example, the electric field shielding member 158 inner tank 130 to the free end of the electric-field shield member 158 made of rubber seal The guide part 152 is fixed in pressure contact with the inner peripheral surface. In this example, the electric field shielding member 158 is installed on the anode side of the guide unit 152, but it may be installed on the cathode (substrate) side of the guide unit 152 or on both sides of the guide unit 152. .

  In the above example, the adjustment plate moving mechanism 142 moves the adjustment plate 134 in the left-right direction in parallel with the substrate W. However, the adjustment plate 134 moves in the left-right and vertical (vertical) directions in parallel with the substrate W. You may make it move to. FIG. 39 shows an adjustment plate moving mechanism 160 in which the adjustment plate 134 is moved in the left and right and up and down directions in parallel with the substrate W. The adjustment plate moving mechanism 160 is different from the adjustment plate moving mechanism 142 shown in FIG. 37 in that a female screw that penetrates up and down and is subjected to a helicate process is provided in the outward projecting portion of the holding portion 140 of the adjustment plate. The upper and lower pressing bolts 162 are screwed to each other, the lower end surface of the upper and lower pressing bolts 162 is brought into contact with the upper end surface of the adjustment plate support portion 144, and further, the plating tank 10 is formed at the projecting end portion of the gripping portion 140 outward. A long hole extending in the width direction is provided, and a vertical fixing bolt 164 is inserted into the long hole, and a lower portion of the vertical fixing bolt 164 is screwed into a female screw provided on the adjustment plate support portion 144. In this example, the left and right fixing bolts are omitted.

  According to this example, when the vertical pressing bolt 162 is rotated in the tightening direction, the tip of the vertical pressing bolt 162 comes into contact with the upper end surface of the adjustment plate support 144 and the adjustment plate 134 is moved upward by the reaction force pressing the upper end surface. Moving. Conversely, when the up-down pressing bolt 162 is turned in the loosening direction, the adjustment plate 134 moves downward. When the vertical and horizontal directions of the adjustment plate 134 with respect to the substrate W are determined, the lower portion of the vertical fixing bolt 164 is screwed into a female screw provided on the adjustment plate support 144 to fix the adjustment plate 134.

  Instead of the pressing bolts 148 and 162, an air cylinder, a servo motor, or the like may be used. Also, the adjustment plate moving mechanism 142 shown in FIG. 37 and the adjustment plate moving mechanism 160 shown in FIG. 39 may be combined so that the vertical and horizontal positions of the adjustment plate 134 can be adjusted. In that case, by providing a long hole extending in the vertical direction through which the left and right fixing bolt 150 passes in the bracket 146, the adjusting plate 134 can be fixed by the left and right fixing bolt 150 even if the position of the adjusting plate 134 is shifted in the vertical direction. In the adjustment plate moving mechanism 160 shown in FIG. 39, the left and right presser bolts 148 may be omitted and only the vertical (vertical) direction positioning of the adjustment plate 134 with respect to the substrate W may be performed.

As described above, the horizontal position of the adjustment plate 134 relative to the substrate W is finely adjusted via the adjustment plate moving mechanism 142 , and the horizontal and vertical directions of the adjustment plate 134 relative to the substrate W are determined via the adjustment plate moving mechanism 160. By finely adjusting the position, the in-plane uniformity of the film thickness of the plating film formed on the surface of the substrate W can be improved. In particular, since the adjustment plate 134 is disposed at a position close to the substrate W, fine adjustment of the position of the adjustment plate 134 in the vertical or horizontal direction with respect to the substrate W can be performed by the plating film formed on the surface of the substrate W. This is important for improving the in-plane uniformity of the film thickness.

  40 and 41 show still another example of the adjustment plate, which adds the following configuration to the adjustment plate 134 shown in FIG. That is, an auxiliary adjustment plate attachment portion for attaching the auxiliary adjustment plate 170 is provided on the anode side surface of the main body 136 of the adjustment plate 134. The auxiliary adjusting plate mounting portion is composed of a pair of side hooks 172a and bottom hooks 172b each having a hook shape in cross section, which are fixed at positions corresponding to the peripheral side and lower end corners of the auxiliary adjusting plate 170. . Accordingly, the auxiliary adjustment plate 170 can be installed at a predetermined position with respect to the adjustment plate 134 by inserting the auxiliary adjustment plate 170 into the auxiliary adjustment plate mounting portion including the side hook 172a and the bottom hook 172b of the adjustment plate 134. ing.

  In this example, an adjustment plate (8-inch wafer adjustment plate) having an 8-inch wafer opening 134a is used as the adjustment plate 134, and an adjustment plate (6-inch wafer opening 170a) is used as the auxiliary adjustment plate 170. 6 inch wafer adjustment plate) is used. As a result, when the substrate W is changed from an 8-inch wafer to a 6-inch wafer, the auxiliary adjustment plate (6-inch wafer adjustment plate) 170 is adjusted to the adjustment plate (8-inch wafer adjustment plate) without replacing the adjustment plate itself. This can be dealt with just by installing it at 134. A grip opening 170 b is provided on the auxiliary adjustment plate 170.

The horizontal dimension t ₃ , t ₄ and the vertical dimension t ₅ of the adjustment plate 134 and the auxiliary adjustment plate 170 are generally 5 mm or more and preferably 10 mm or more. Thereby, when the auxiliary adjustment plate 170 is installed on the adjustment plate 134, the potential line generated from the anode 26 does not pass through the opening 170a of the auxiliary adjustment plate 170, and the adjustment plate 134 and the auxiliary adjustment are made from the outside of the auxiliary adjustment plate 170. It is possible to prevent the adjustment plate 134 from coming off from the opening 134a through the gap between the plate 170 and the plate 170.

  In the above example, an example in which an 8-inch adjustment plate and a 6-inch wafer adjustment plate are combined has been shown. However, any two adjustment plates (first adjustment plate and second adjustment plate) may be combined. By adopting a structure that can be used, plating is usually performed using only the first adjustment plate, and when the electric field distribution needs to be finely adjusted according to the type of the substrate (substrate to be plated), the first The operation of using the second adjustment plate in combination with the adjustment plate can be performed.

  FIG.42 and FIG.43 shows the principal part of the plating apparatus of further another embodiment of this invention. This example differs from the plating apparatus shown in FIG. 1 in that an anode holder 28 having a wide gripping portion 180 on the upper portion shown in FIG. 43 and an adjusting plate having a wide gripping portion 140 shown in FIG. 134, the anode holder 28 is disposed via the gripping portion 180 and the adjustment plate 134 is disposed via the gripping portion 140 on the single positioning holding portion 182 installed across the upper end opening of the plating tank 10. The substrate holders 24 are respectively installed via the holder arms 64 (see FIG. 9). That is, the gripping portion 180 of the anode holder 28, the gripping portion 140 of the adjustment plate 134, and the holder arm 64 of the substrate holder 24 are placed and placed on the positioning holding portion 182 that is the same member. Accordingly, the central axes of the anode 26 held by the anode holder 28, the cylindrical portion 136 of the adjustment plate 134, and the substrate W held by the substrate holder 24 can be reliably aligned.

  In this example, the gripping portion 180 of the anode holder 28, the gripping portion 140 of the adjustment plate 134, and the holder arm 64 of the substrate holder 24 are placed on the positioning holding portion 182 that is the same member. 28, the adjustment plate 134, and other portions of the substrate holder 24 may be placed on the positioning holding portion 182, respectively. In short, the anode holder 28, the adjustment plate 134, and the substrate holder 24 may be positioned in the vertical direction with reference to the positioning holding portion 182 that is the same member.

  44 and 45 show still another example of the adjustment plate. In this example, the following configuration is added to the adjustment plate 134 shown in FIG. In other words. A partition 188 is fixed to the surface of the main body 138 on the anode side of the adjustment plate 134 through a fixing plate 184 and a fixing bolt 186 so as to cover the entire central opening 134a. The diaphragm 188 is composed of a cation exchanger that does not allow additives to pass through metal ions, or a functional membrane (neutral filtration membrane). Thus, the opening 134a of the adjusting plate 134 is covered with the partition 188. Thus, it is possible to prevent the additive contained in the plating solution from being decomposed and consumed on the surface of the anode 26.

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

It is a vertical front view which shows the plating apparatus of embodiment of this invention. It is a top view which shows the paddle of the plating apparatus shown in FIG. It is AA sectional drawing of FIG. FIG. 4 is a view corresponding to FIG. 3 showing a modified example of a different paddle. It is the schematic which shows the paddle drive mechanism of the plating apparatus shown in FIG. 1 with a plating tank. It is a top view which shows the relationship of the paddle in the stroke end of a paddle. It is a perspective view which shows the adjustment plate of the plating apparatus shown in FIG. It is a side view which shows the other example of an adjustment board. It is a figure which shows the relationship between the board | substrate holder of the plating apparatus shown in FIG. 1, and the holder support part of a plating tank. It is a perspective view which expands and shows the periphery of the holder arm of the plating apparatus shown in FIG. It is sectional drawing which shows the state which the holder arm and the holder support part contacted. It is a right view of FIG. It is a perspective view which shows the other example of an arm support part. It is a top view which shows the separation plate of the plating apparatus shown in FIG. It is a top view which shows the other example of a separation plate. It is sectional drawing which shows the installation state to the plating tank side plate of the separation plate in the plating apparatus shown in FIG. It is a perspective view which shows the relationship between the separation plate in the plating apparatus shown in FIG. 1, a shielding board, and the bottom part of a plating tank. It is a perspective view which shows the other relationship of a separation plate, a shielding board, and the bottom part of a plating tank. It is sectional drawing which shows the relationship between the flange part of the adjustment plate in the plating apparatus shown in FIG. 1, and a separating plate. It is the figure seen from the upper part of the plating tank which shows the principal part of an example, attaching an adjustment board so that the distance with a board | substrate can be adjusted. It is a flowchart which shows the copper-plating process process in bump formation. It is a figure which shows the shape of a bump at the time of forming a bump by plating by setting the current density to 8 ASD and the average absolute value of the paddle stirring moving speed to 20 cm / sec. It is a figure which shows the shape of a bump in the case of forming a bump by plating with a current density of 8 ASD and an average absolute value of paddle stirring moving speed of 83 cm / sec. It is the microscope picture of a bump | vamp at the time of setting the average of the absolute value of a paddle stirring moving speed to 40 cm / sec, and forming a bump by plating using a paddle with a thickness of 2 mm. It is the microscope picture of a bump | vamp at the time of setting the average of the absolute value of a paddle stirring moving speed to 40 cm / sec, and forming a bump by plating using a paddle with a thickness of 4 mm. It is the microscope picture of a bump at the time of setting the average of the absolute value of a paddle stirring moving speed to 67 cm / sec, and forming a bump by plating using a paddle with a thickness of 4 mm. It is the microscope picture of a bump at the time of setting the average of the absolute value of a paddle stirring moving speed to 83 cm / sec, and forming a bump by plating using a paddle with a thickness of 4 mm. It is the microscope picture of a bump | vamp at the time of setting the average of the absolute value of a paddle stirring moving speed to 83 cm / sec, and forming a bump by plating using a paddle with a thickness of 3 mm. It is a figure which shows distribution of bump height at the time of plating using the plating tank which does not install a shielding board under a separating plate, and forming a bump. It is a figure which shows distribution of bump height at the time of performing plating using the plating tank which installed the shielding board under the separation plate, and forming a bump. When the average absolute value of the paddle stirring movement speed is set to 20 cm / sec, a 5 mm thick flat plate with an adjustment plate having one opening at the center, and a bump is formed with a distance of 35 mm from the substrate It is a graph which shows the in-plane uniformity of bump height. Graph showing the in-plane uniformity of the bump height when the average absolute value of the paddle stirring moving speed is set to 83 cm / sec, the bump is formed using the adjustment plate shown in FIG. It is. It is a figure which shows the relationship of the X-axis and Y-axis in FIG.31 and FIG.32. It is a vertical front view which shows the plating apparatus of other embodiment of this invention. It is a top view which shows the other drive mechanism of a paddle with a plating tank. It is a vertical front view of FIG. It is a vertical side view which shows the other adjustment board provided with the adjustment board moving mechanism, and another plating tank. It is the BB sectional drawing of FIG. It is a figure which shows the principal part of the adjustment plate provided with the other adjustment plate movement mechanism, and a plating tank. It is a front view which shows another adjustment board. It is a top view of FIG. It is a vertical front view which shows the principal part of the plating apparatus of further another embodiment of this invention. It is a front view which shows the anode holder and positioning holding | maintenance part which are used for the plating apparatus shown in FIG. It is a front view which shows another adjustment board. It is CC sectional view taken on the line of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Plating tank 12 Overflow tank 18 Plating solution supply port 20 Constant temperature unit 22 Filter 24 Substrate holder 26 Anode 28 Anode holder 32 Paddle 32a Long hole 32b Lattice part 34 Adjustment plate 42 Paddle drive part 44 Motor 46 Control part 50 Cylindrical part 52 Flange Part 60 holder grip part 62 holder support part 64 holder arm 66 arm side contact 68 support part side contact 70 arm side magnet 72 support part side magnet 80 separation plate 80a plating solution through hole 82 shielding plate 84 substrate processing chamber 86 plating solution dispersion chamber 90 Separator support part 94 Electric field shielding member (rubber sheet)
96 Adjustment plate fixing slit plate 100 Electric field shielding member (rubber sheet)
110 Anode side liquid separation chamber 112 Cathode side liquid separation chamber 120 Paddle pressers 122a, 122b Coupling,
134 Adjustment plate 136 Cylindrical part 138 Main body part 140 Grasping part 142 Adjustment plate moving mechanism,
144 Adjustment plate support portion 146 Bracket 148 Left and right pressing bolt 150 Left and right fixing bolt 152 Guide portion 158 Electric field shielding member (rubber sheet)
160 Adjustment plate moving mechanism 162 Up / down pressing bolt 164 Up / down fixing bolt 170 Auxiliary adjustment plate 172a Side hook (auxiliary adjustment plate mounting portion)
172b Bottom hook (auxiliary adjustment plate mounting part)
180 Grasping part 182 Positioning / holding part 188 Bulkhead

Claims (14)

A plating tank for holding a plating solution;
An anode disposed by being immersed in a plating solution in the plating tank;
A holder for holding a substrate and arranging the substrate at a position facing the anode;
A plate-like member having a plurality of grating portions, wherein disposed between the anode and the substrate held by the holder, a paddle for stirring the plating solution in parallel to reciprocate with said substrate,
An adjustment plate made of a dielectric material and disposed between the anode and the paddle to make the potential distribution uniform over the entire surface of the substrate;
A control unit that controls a paddle driving unit that drives the paddle;
Wherein, the average of the absolute value of the moving speed of the paddle Ri Do the 70~100cm / sec, and so that the position of the grating portion of the paddle at the stroke end of the left and right of the paddle is moved do not overlap each other A plating apparatus for controlling the paddle driving unit. The plating apparatus according to claim 1 , wherein the plate-like member has a constant thickness of 3 to 5 mm. The plating apparatus according to claim 1, wherein a distance between the paddle and the substrate is 5 to 11 mm. It is formed between the front Symbol adjusting plate, a cylindrical portion having a shape among along the outer shape of the substrate, and the anode side end portion connected to the anode the substrate to the outer periphery of the cylindrical portion The plating apparatus according to any one of claims 1 to 3 , further comprising a flange portion that blocks an electric field. The plating apparatus according to claim 4 , wherein a distance between the end of the cylindrical portion on the substrate side and the substrate is 8 to 25 mm. The holder has a holder arm that protrudes outward, and the plating tank has a holder support portion that contacts the holder arm and supports the holder in a suspended manner, and a contact portion between the holder arm and the holder support portion. the plating apparatus according to any one of claims 1 to 5, characterized in that fixing means for fixing the holder arm to the holder supporting portion. The plating apparatus according to claim 6, wherein the fixing means includes a magnet provided on at least one of the holder arm and the holder support portion. At least a part of the contact portion between the holder arm and the holder support portion has a contact point that contacts and closes when the holder is suspended and supported in the plating tank, and the contact point closes to the substrate . The plating apparatus according to claim 6 , wherein power is supplied. The said adjustment plate has an opening part, The anode side of this opening part is entirely covered with the partition which does not let an additive pass through a metal ion, The any one of Claim 1 thru | or 8 characterized by the above-mentioned. The plating apparatus as described. Install the anode and substrate in the plating solution in the plating tank so that they face each other.
A paddle made of a plate-like member having a plurality of lattice portions is disposed between the anode and the substrate held by the holder,
An adjustment plate made of a dielectric and making the potential distribution over the entire surface of the substrate more uniform is disposed between the anode and the paddle,
While applying a voltage between the anode and the substrate, the paddle, at a moving speed average of the absolute value is 70~100cm / sec, and the of the paddles in the stroke end of the left and right of the paddle is moved A plating method characterized by reciprocating in parallel with the substrate so that the positions of the lattice portions do not overlap each other . The plating method according to claim 10 , wherein the plate-like member has a constant thickness of 3 to 5 mm. The plating method according to claim 10 or 11 , wherein a distance between the paddle and the substrate is 5 to 11 mm. The adjusting plate, the electric field formed between the cylindrical portion having a shape among along the outer shape of the substrate, and the anode side end portion connected to the anode the substrate to the outer periphery of the cylindrical portion the plating method according to any one of claims 10 to 12, characterized in that have a flange portion for blocking. The plating method according to claim 13 , wherein a distance between the end of the cylindrical portion on the substrate side and the substrate is 8 to 25 mm.

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