JP6254307B2 - Method for inspecting leakage of substrate holder used in plating equipment - Google Patents

Description

  The present invention relates to a leakage inspection method for a substrate holder used in, for example, a plating apparatus for plating a surface to be plated (surface) of a substrate, and in particular, fine wiring grooves and holes provided on the surface of a semiconductor wafer or the like, For a substrate holder of a plating apparatus used to form a plating film in a resist opening or to form a bump (projection electrode) electrically connected to a package electrode or the like on the surface of a semiconductor wafer The present invention relates to a method for performing a leak test. The plating apparatus has, for example, a large number of via plugs penetrating vertically therein, and is also used for embedding via holes when manufacturing an interposer or spacer used for so-called three-dimensional mounting such as a semiconductor chip.

  For example, in the case of TAB (Tape Automated Bonding) and flip chip, protruding connection in which gold, copper, solder, or nickel is laminated in multiple layers at a predetermined location (electrode) on the surface of a semiconductor chip on which wiring is formed An electrode (bump) is formed and electrically connected to a package electrode or a TAB electrode through the bump. There are various bump forming methods such as electroplating, vapor deposition, printing, and ball bump. However, miniaturization is possible as the number of I / Os in the semiconductor chip increases and the pitch decreases. Many electrolytic plating methods with relatively stable performance are being used.

  Here, the electrolytic plating method includes a jet type or cup type in which a surface to be plated of a substrate such as a semiconductor wafer is placed horizontally (face down), and a plating solution is sprayed from below to perform plating, and in a plating tank. The dip type is roughly classified into a dip type in which the substrate is set up vertically and a plating solution is poured from the bottom of the plating tank to cause overflow. The electrolytic plating method using the dip method has the advantages of good bubble removal that adversely affects the quality of plating and a small footprint. It is considered suitable for bump plating that requires a long time.

  In an electroplating apparatus adopting a conventional dip method, a substrate holder is provided which holds a substrate such as a semiconductor wafer in a detachable manner by sealing the outer periphery thereof and exposing the surface (surface to be plated). Is soaked in the plating solution together with the substrate, so that the surface of the substrate is plated.

  Since the substrate holder is used by being immersed in the plating solution, when the substrate is held by the substrate holder and immersed in the plating solution, the back surface of the substrate (the surface to be plated) and the outer peripheral portion of the substrate that comes in contact with the electrical contacts It is necessary to securely seal the outer peripheral portion of the substrate so that the plating solution does not enter. For this reason, for example, in a substrate holder in which a substrate is detachably held by a pair of supports (holding members), a seal member is attached to one support, and the seal member is attached to the other support and the support. The outer peripheral portion of the substrate is sealed by being brought into pressure contact with the outer peripheral portion of the mounted and held substrate.

  In this type of substrate holder, the shape and fixing method of the sealing member is optimized, the sealing member is periodically cleaned (including every leaf), the sealing member is periodically replaced, Improves the accuracy of substrate pretreatment (seed layer and resist film generation), minimizes the setting error of the substrate to the substrate holder, and periodically re-adjusts the plating solution. Eliminate leaks.

  However, it is quite difficult to achieve seal integrity due to deterioration of the seal member and the like. In particular, when plating is performed to embed a plating film in fine recesses such as trenches and via holes, in order to allow the plating solution to easily and surely enter the fine recesses, in general, good permeability Therefore, it is more difficult to provide a complete seal. Also, it is generally difficult to detect leakage of plating solution or the like. And once the plating solution leaks, not only does the plating solution leaking inside the substrate holder adhere to the outer periphery and back surface of the substrate, it moves to the substrate transport device and stains the entire device with the plating solution, The leaked plating solution will corrode the contacts and prevent energization.

  For this reason, the applicant, for immersing the substrate held by the substrate holder in the plating solution together with the substrate holder, detects whether or not the plating solution has leaked. A substrate holder (refer to Patent Document 1) that is provided with at least a pair of conductors in the interior to detect (the liquid leakage detection conductor that causes the leakage of the plating solution is energized), and the substrate holder holds the substrate The pressurized gas is supplied into the space surrounded by the sealing member between the substrate and the substrate holder, and the sealing member leaks depending on whether or not the pressure of the pressurized gas is reduced. A substrate holder (see Patent Document 2) that detects whether or not it is present is proposed.

  In addition, after sealing the outer peripheral portion of the substrate with the sealing member, before performing the plating process on the substrate, it is possible to inspect before the plating process whether the plating solution leaks in the space formed by the sealing member. It has been proposed (see Patent Document 3). The leak inspection before the plating process is performed, for example, by reducing or pressurizing the sealed area formed by the seal member.

  In addition, after holding the substrate with the substrate holder while sealing the outer peripheral portion of the substrate with a sealing member, the container housing portion is decompressed and the integrity of the seal is confirmed before the plating process. After holding, the internal space partitioned by the substrate in the substrate holder is sealed by vacuum suction, and the degree of pressure change in the internal space within a certain time is below a certain value (for example, the internal space is minus 0) It is proposed that the pressure is reduced to a negative pressure of about 0.05 atm and sealed, and after 5 seconds, if the change in the negative pressure is within 10%, it is determined that it is acceptable (no leakage)) ( (See Patent Document 4).

JP 2004-52059 A JP 2003-27795 A Japanese translation of PCT publication No. 2002-531702 Special table 2007-509241 gazette

  What is the sealing performance of the seal member by simply vacuuming or pressurizing the internal space partitioned by the substrate held by the substrate holder in the substrate holder and detecting the pressure in the internal space? It is generally difficult to determine if it is incomplete. In addition, when a very small amount of plating solution leaks, the volume ratio between the volume of the internal space in the substrate holder and the amount of leakage of the plating solution increases considerably, and the pressure change in the internal space is inversely proportional to this. Becomes considerably smaller. For example, if the volume of the internal space is 500 cc and the amount of leakage of the plating solution is 0.05 cc, the pressure change in the internal space is 1/10000. For this reason, even if a highly accurate pressure sensor is used, erroneous detection may occur. In particular, in order to continuously and stably operate the plating apparatus, it is required to reliably detect even a very small amount of plating solution leakage in advance or after the fact.

  In addition, when inspecting afterwards whether the plating solution has leaked in the substrate holder used for plating, the already leaked plating solution corrodes the electrical contacts of the substrate holder or increases the electrical contact resistance. Therefore, depending on the degree of leakage of the plating solution, maintenance such as cleaning of the substrate holder and replacement of parts may be required.

  The present invention has been made in view of the above circumstances, so that it is possible to quickly and surely find a serious problem related to the sealing performance of the seal member, and to detect it in advance even for a very small amount of leakage. It is an object of the present invention to provide a leakage inspection method for a substrate holder.

  One aspect of the present invention is a method for performing a leak test on a substrate holder including a first holding member and a second holding member having an opening, wherein one side of the substrate is held in the first holding state. The second holding member is brought into contact with the other surface of the substrate while being supported by the member, and the substrate is held by the substrate holder in a state where the other surface of the substrate is exposed from the opening of the second holding member. When the substrate is held by the substrate holder, the second protrusion of the second holding member is sealed while the space between the first holding member and the second holding member is sealed by the first protrusion of the second holding member. By sealing the outer peripheral portion of the substrate with a portion, the first holding member, the second holding member, and the substrate form an internal space in the substrate holder, and the internal space is evacuated to Check whether the internal space reaches a predetermined vacuum pressure after a certain time. A step leak inspection is performed to check the sealing performance of the first protrusion and the second protrusion, and the internal space is evacuated with respect to the substrate holder holding the substrate that has passed the first step leak inspection. And then performing a second stage leak test for sealing the internal space and checking whether the pressure in the internal space changes to a predetermined value or more within a predetermined time. It is characterized by further inspecting the sealing performance of the protrusion.

In a preferred aspect of the present invention, whether or not the pressure in the internal space changes to a predetermined value or more within a predetermined time is determined simultaneously by the pressure after sealing in the internal space and evacuation in the internal space. It is characterized by measuring and inspecting a pressure difference with a pressure in a master container without gas leakage which is sealed by evacuation.
In a preferred aspect of the present invention, a seal case is disposed so as to cover a surface exposed from the opening of a substrate held by the substrate holder that has passed the second stage leakage inspection, and the first holding member of the substrate holder Forming a sealed space between the substrate holder and the seal case by evacuating the internal space while introducing a tracer gas into the sealed space, Performing a third-stage leak test for checking whether tracer gas is contained in the air sucked from the internal space, and further checking the sealing performance of the first and second projecting portions; To do.
In a preferred aspect of the present invention, the space between the second holding member of the substrate holder and the seal case is sealed, so that the sealed space becomes a substrate-side sealed space in which the second projecting portion is disposed. The first projecting portion is divided into two sealed spaces, a holder-side sealed space in which the first projecting portion is disposed, and the third stage leak test is performed on at least one of the two sealed spaces.

  One reference example of the present invention includes a first holding member and a second holding member having an opening, and the second holding member is supported on the substrate while supporting one surface of the substrate with the first holding member. When the substrate is held in a state where the other surface of the substrate is exposed from the opening of the second holding member and the first protrusion of the second holding member causes the first While sealing between the holding member and the second holding member, the outer peripheral portion of the substrate is sealed with the second projecting portion of the second holding member, whereby the first holding member, the second holding member, and the An internal space is formed in the substrate holder with the substrate, the substrate holder having an internal passage communicating with the internal space, and a suction line extending from a vacuum source, and attached to and detached from the substrate holder so as to communicate with the internal passage A suction joint that can be mounted freely and the suction line A pressure sensor for inspecting whether or not the internal space reaches a predetermined vacuum pressure after a predetermined time when the internal space is evacuated, and the internal space when the internal space is sealed by evacuating through the suction line A pressure change detection unit that detects a pressure change in the space, and evacuates the internal space to perform a first-stage leak test for checking whether the internal space reaches a predetermined vacuum pressure after a predetermined time. Inspecting the sealing performance of the first protrusion and the second protrusion, and sealing the internal space with respect to the substrate holder holding the substrate that has passed the first stage leakage inspection, the pressure in the internal space The second stage leakage inspection is performed to inspect whether or not the value changes to a predetermined value or more within a predetermined time, and the sealing performance of the first protrusion and the second protrusion is further inspected. Passed board holder A plating apparatus characterized by being configured to plating the substrate in the plating bath used.

In a preferred embodiment of the above reference example, the pressure change detection unit is configured to ensure that no gas leakage occurs and is connected to a vacuum source, and the difference between the pressure in the master container and the pressure in the internal space. It has a differential pressure sensor for measuring pressure.
In a preferred embodiment of the above reference example, the internal passage of the substrate holder is formed in the first holding member, the substrate holder includes a suction port connected to the internal passage, and the suction port is connected to the suction line. It is configured to be detachably connected.
In a preferred aspect of the above reference example, the plating apparatus includes a substrate attachment / detachment unit that attaches / detaches the substrate to / from the substrate holder, and the first stage leakage inspection and the second stage leakage inspection are performed by the substrate attachment / detachment unit. It is characterized by that.
In a preferred aspect of the above reference example, the plating apparatus includes a cassette table on which a cassette for housing a substrate is placed, a substrate transfer device that transfers a substrate between the cassette table and the substrate attaching / detaching portion, and a substrate holder And a substrate holder transport device for transporting the substrate holder, and the substrate held by the substrate holder that has failed the first stage leakage inspection and the second stage leakage inspection is returned to the cassette. The holder is configured to return to the stocker.

  One reference example of the present invention is a plating method for plating a substrate while holding the substrate with a substrate holder including a first holding member and a second holding member having an opening, and one surface of the substrate The second holding member is brought into contact with the other surface of the substrate while being supported by the first holding member, and the other surface of the substrate is exposed from the opening of the second holding member. Is held by the substrate holder, and when the substrate is held by the substrate holder, the second holding member is sealed between the first holding member and the second holding member by the first projecting portion of the second holding member. By sealing the outer peripheral portion of the substrate with the second projecting portion of the member, the first holding member, the second holding member, and the substrate form an internal space in the substrate holder, The internal space is evacuated to a predetermined vacuum pressure after a certain time. A first stage leak inspection is performed to inspect whether or not, and the internal space is sealed with respect to the substrate holder holding the substrate that has passed the first stage leak inspection, and the pressure in the internal space is within a predetermined time. A seal case is formed so as to cover the surface exposed from the opening of the substrate held by the substrate holder that has passed the second-stage leakage inspection, and performs a second-stage leakage inspection for inspecting whether or not the value changes to a predetermined value or more. And a sealed space is formed between the substrate holder and the seal case by sealing between the first holding member of the substrate holder and the seal case, and tracer gas is introduced into the sealed space. The inside space was evacuated while being introduced, and a third stage leak inspection was conducted to check whether tracer gas was contained in the air sucked from the interior space, and passed the third stage leak inspection. substrate Characterized by plating the substrate with a holder.

In a preferred embodiment of the above reference example, whether or not the pressure in the internal space changes to a predetermined value or more within a predetermined time is determined by the pressure after sealing in the internal space and evacuation in the internal space. At the same time, the pressure difference from the pressure in the master container without gas leakage which is sealed by vacuuming is measured by a differential pressure sensor and inspected.
A preferred aspect of the above reference example is that the space between the second holding member of the substrate holder and the seal case is sealed, so that the sealed space is replaced with the substrate-side sealed space in which the second protrusion is disposed. And the first projecting portion is divided into two sealed spaces of a holder-side sealed space in which the third projecting section is subjected to the third-stage leakage test on at least one of the two sealed spaces. .
In a preferred aspect of the above reference example, the first stage leakage inspection, the second stage leakage inspection, and the third stage leakage inspection are performed by a substrate attaching / detaching portion for mounting a substrate to be plated on the substrate holder. It is characterized by that.

  One reference example of the present invention is a plating method for plating a substrate while holding the substrate with a substrate holder including a first holding member and a second holding member having an opening, and one surface of the substrate The second holding member is brought into contact with the other surface of the substrate while being supported by the first holding member, and the other surface of the substrate is exposed from the opening of the second holding member. Is held by the substrate holder, and when the substrate is held by the substrate holder, the second holding member is sealed between the first holding member and the second holding member by the holder-side sealing member of the second holding member. By sealing the outer periphery of the substrate with the substrate-side sealing member of the member, the first holding member, the second holding member, and the substrate form an internal space in the substrate holder, and the substrate holder holds the inner space. Exposed from the opening of the substrate A sealing case is disposed so as to cover the surface; the substrate holder is sealed between the first holding member of the substrate holder and the sealing case to form a sealed space between the substrate holder and the sealing case; By sealing between the second holding member of the holder and the seal case, the sealed space is formed into a substrate-side sealed space in which the substrate-side seal member is disposed, and the holder-side seal member is disposed in the interior. Dividing into two sealed spaces of the holder-side sealed space to be arranged, and introducing the tracer gas into at least one of the two sealed spaces, evacuating the internal space, and into the air sucked from the internal space Leakage inspection for inspecting whether tracer gas is contained is performed.

  In a preferred aspect of the above reference example, the leakage inspection is performed by a substrate attaching / detaching portion for mounting a substrate to be plated on the substrate holder.

  One reference example of the present invention includes a first holding member and a second holding member having an opening, and the second holding member is supported on the substrate while supporting one surface of the substrate with the first holding member. When the substrate is held in a state where the other surface of the substrate is exposed from the opening of the second holding member and the first protrusion of the second holding member causes the first While sealing between the holding member and the second holding member, the outer peripheral portion of the substrate is sealed with the second projecting portion of the second holding member, whereby the first holding member, the second holding member, and the An internal space is formed in the substrate holder with the substrate, the substrate holder having an internal passage communicating with the internal space, and a suction line extending from a vacuum source and connected to the internal passage so as to communicate with the internal passage A suction joint that is detachably attached, and the suction line. A pressure sensor for inspecting whether the internal space reaches a predetermined vacuum pressure after a predetermined time when the internal space is evacuated through, and the internal space when the internal space is evacuated and sealed through the suction line A pressure change detection unit that detects a pressure change in the substrate, a seal case that covers a surface of the substrate held by the substrate holder that is exposed from the opening, and the first holding member and the seal case of the substrate holder. A tracer gas seal member that forms a sealed space between the substrate holder and the seal case by sealing the space, a tracer gas introduction part that introduces a tracer gas into the sealed space, and a gas flowing through the suction line And a tracer gas tester for detecting whether or not the tracer gas is contained in the plating apparatus.

In a preferred embodiment of the above reference example, the pressure change detection unit is configured to ensure that no gas leakage occurs and is connected to a vacuum source, and the difference between the pressure in the master container and the pressure in the internal space. It has a differential pressure sensor for measuring pressure.
A preferable aspect of the reference example is that the space between the second holding member and the seal case of the substrate holder is sealed, so that the sealed space is replaced with the substrate-side sealed space in which the substrate-side seal member is disposed. The holder-side seal member is further divided into two sealed spaces, ie, a holder-side sealed space in which the holder-side seal member is disposed.

  In the plating method according to one reference example, the substrate is held by the substrate holder while the outer peripheral portion of the substrate is sealed by the sealing member, and when the substrate is held by the substrate holder, the substrate is hermetically sealed by the sealing member. A substrate that holds a substrate that has passed the first-stage leakage inspection by performing a first-stage leakage inspection that evacuates the formed internal space and inspects whether the internal space reaches a predetermined vacuum pressure after a predetermined time. A second-stage leak test is performed on the holder to seal the internal space and check whether the pressure in the internal space changes to a predetermined value or more within a predetermined time.

  In this way, the first stage leak inspection that can be completed in a relatively short time is carried out, and the leakage of the plating solution due to obvious operation mistakes or poor maintenance is quickly and quickly detected. By reducing the load on the stage leakage inspection and then performing the second stage leakage inspection, it is possible to reliably and quickly find a serious defect related to the sealing performance of the sealing member of the substrate holder and take appropriate measures against this leakage. It can be carried out.

  A preferred aspect of the above reference example is to determine whether or not the pressure in the internal space changes to a predetermined value or more within a predetermined time, whether the pressure in the internal space is sealed, and the vacuum in the internal space. The pressure difference with the pressure in the master container without gas leakage that is sealed by vacuuming simultaneously is measured with a differential pressure sensor and inspected.

  Thus, when measuring the pressure change in the internal space by using the pressure difference between the pressure in the internal space and the pressure in the master container, the pressure change in the internal space is directly measured using the pressure sensor. In comparison, a minute pressure change in the internal space can be detected more accurately.

  In a preferred embodiment of the above reference example, a substrate holder that holds a substrate that has passed the second stage leakage inspection is sealed between the substrate held by the substrate holder and a seal case that covers the surface of the substrate. A third stage leak that forms a sealed space, evacuates the internal space while introducing a tracer gas into the sealed space, and checks whether the air drawn from the internal space contains the tracer gas Conduct an inspection.

  Thus, even if the micro leak occurs in the seal member by performing the third stage leak inspection that requires a relatively long time for the substrate holder that has passed the second stage leak inspection, This can be reliably detected.

  A preferable aspect of the above reference example is that the sealed space is pressed against the outer peripheral portion of the substrate to seal the outer peripheral portion, the substrate-side sealed space around the substrate-side seal member, and the holder-side seal member that seals the holder surface Is divided into two spaces, ie, a holder-side sealed space around the, and the third stage leakage inspection is performed on at least one of the two spaces.

  As a result, it is possible to identify whether the leak occurs in the holder-side seal member or the substrate-side seal member, or in both the holder-side seal member and the substrate-side seal member, and to take measures suitable for the place where the leak occurs. Can be applied. In addition, if the third stage leakage inspection is performed separately in the holder-side sealed space and the substrate-side sealed space, the inspection time becomes longer. For this reason, for example, when it is not necessary to specify whether the leakage occurs in the holder side sealing member or on the substrate side sealing member side, the sealed space is not divided into two spaces, but as one space. By performing the third stage leakage inspection, the inspection time can be shortened.

  In the plating method according to another reference example, the substrate is held by the substrate holder while the outer periphery of the substrate is sealed with a sealing member, and the substrate is held between the substrate held by the substrate holder and the sealing case covering the surface of the substrate. Forming a sealed space and introducing a tracer gas into the sealed space, and evacuating the inner space formed inside the substrate holder that is sealed with the seal member when the substrate is held by the substrate holder. Then, a leakage inspection is performed to inspect whether the tracer gas is contained in the air sucked from the internal space.

  This leak inspection is performed, for example, as an off-line inspection for confirming the state of each substrate holder periodically or before the start of operation or after the end of operation. A dummy substrate may be used in place of the substrate when performing a leakage inspection by an off-line inspection.

  In a preferred aspect of the above reference example, the leakage inspection is performed by a substrate attaching / detaching unit that attaches / detaches the substrate to / from the substrate holder. Thereby, it is possible to perform a leakage inspection of the substrate holder immediately before starting the plating process immediately after the substrate is held by the substrate holder.

  A plating apparatus according to a reference example includes a seal member that seals an outer peripheral portion of a substrate, and a substrate holder having an internal passage that is sealed by the seal member and communicates with an internal region that is formed inside when the substrate is held. A suction joint that is connected to a suction line extending from a vacuum source and is detachably attached to the substrate holder so as to communicate with the internal passage; and when the interior space is evacuated through the suction line, the interior space is constant. A pressure sensor for inspecting whether a predetermined vacuum pressure is reached after a time, and a pressure change detection unit for detecting a pressure change in the internal space when the internal space is vacuumed and sealed through the suction line.

  In a preferred aspect of the above reference example, the pressure change detection unit is configured to ensure that a gas leak does not occur and is connected to a vacuum source, a pressure in the master container, and a pressure in the internal space. A differential pressure sensor for measuring the differential pressure is included.

  In a preferred aspect of the above reference example, a seal case that covers a surface of the substrate held by the substrate holder and forms a sealed section that accommodates the substrate inside the substrate holder, and a tracer gas in the sealed space And a tracer gas tester for detecting whether the gas flowing along the suction line contains the tracer gas.

  In a preferred aspect of the above reference example, the seal case seals the substrate-side sealed space around the substrate-side seal member that presses the sealed space against the outer peripheral portion of the substrate to seal the outer peripheral portion, and the holder surface. A separating seal member that divides the holder-side sealed space around the holder-side seal member into two spaces.

  According to the present invention, in the first stage leakage inspection of the substrate holder that can be completed in a relatively short time, a plating solution leakage due to an obvious operation error or poor maintenance is quickly and promptly detected. By performing the second stage leakage inspection on the substrate holder that has passed the stage leakage inspection, the second stage leakage inspection reliably and quickly finds a serious defect related to the sealing performance of the sealing member of the substrate holder. Appropriate processing can be performed. As a result, it is possible to estimate the cause of the leakage, find out the content of the defect at an early stage, and shorten the time required for maintenance.

1 is an overall layout diagram of a 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 figure which shows typically the state at the time of performing the 1st step | paragraph leak test | inspection and the 2nd step | paragraph leak test | inspection with respect to the substrate holder holding the board | substrate. It is a figure which shows typically the state when performing the 3rd step | paragraph leak test | inspection with respect to the board | substrate holder holding the board | substrate. It is a flowchart which shows the process flow of the 1st step leak test | inspection with respect to the substrate holder holding the board | substrate, and a 2nd step leak test. It is a figure which shows typically the principal part of the plating apparatus of other embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows an overall layout of a plating apparatus in an embodiment of the present invention. As shown in FIG. 1, this plating apparatus includes two cassette tables 12 on which a cassette 10 containing a substrate such as a semiconductor wafer is mounted, and an aligner 14 that aligns the orientation flats, notches, etc. of the substrate in a predetermined direction. And a spin rinse dryer 16 for rotating the substrate after plating treatment at high speed to dry the substrate. Further, a substrate attaching / detaching portion 20 is provided near the substrate holder 18 for mounting and removing the substrate from and to the substrate holder 18, and a substrate is transported between these units at the center. A substrate transfer device 22 composed of a transfer robot is arranged.

  Then, in order from the substrate attaching / detaching unit 20 side, a stocker 24 for storing and temporarily placing the substrate holder 18, a pre-wet bath 26 for immersing the substrate in pure water, and an oxide film on the surface of the seed layer formed on the surface of the substrate A pre-soak tank 28 for etching away, a first water-washing tank 30a for washing the substrate after pre-soaking, a blow tank 32 for draining the substrate after washing, a second water-washing tank 30b for washing the substrate after plating, and a plating tank 34 Are arranged in order. The plating tank 34 is configured to accommodate a plurality of plating cells 38 inside the overflow tank 36, and each plating cell 38 accommodates one substrate therein and performs plating such as copper plating. It has become.

  Furthermore, a substrate holder transport device 40 that employs, for example, a linear motor system is provided that is located on the side of each device and transports the substrate holder 18 together with the substrate 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 and the stocker 24, a stocker 24, a pre-wet tank 26, a pre-soak tank 28, washing tanks 30a and 30b, and a blow tank. 32 and a plating tank 34, a second transporter 44 is provided for transporting the substrate. Only the first transporter 42 may be provided without providing the second transporter 44.

  A paddle driving device for driving a paddle (not shown) as an agitation rod located inside each plating cell 38 and stirring the plating solution is disposed on the opposite side of the substrate holder conveying device 40 across the overflow tank 36. 46 is arranged.

  The board attaching / detaching unit 20 includes a flat plate-like mounting plate 52 that is slidable in the lateral direction along the rail 50. Two board holders 18 are placed in parallel on the mounting plate 52 in a horizontal state. Then, after the substrate is transferred between the one substrate holder 18 and the substrate transfer device 22, the mounting plate 52 is slid in the horizontal direction so that the other substrate holder 18 and the substrate transfer device 22 can be moved. In order to deliver the board.

  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. In this example, the second holding member 58 is configured to be openable and closable via the hinge 56. However, for example, the second holding member 58 is disposed at a position facing the first holding member 54. The second holding member 58 may be advanced toward the first holding member 54 to open and close.

  The second holding member 58 includes a base portion 60 and a ring-shaped seal holder 62, and is made of, for example, vinyl chloride to improve sliding with the presser ring 64 described below. On the surface of the seal holder 62 facing the first holding member 54, when the substrate W is held by the substrate holder 18, a substrate-side seal member 66 that presses against and seals the outer peripheral portion of the surface of the substrate W is inward. Protrusively installed. Further, a holder side seal member 68 is attached to the surface of the seal holder 62 facing the first holding member 54 so as to press and seal the first holding member 54 at a position outside the substrate side sealing member 66. Yes.

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

  A step portion is provided on the outer peripheral portion of the seal holder 62 of the second holding member 58, 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 a presser plate 72 (see FIG. 3) attached to the side surface of the seal holder 62 so as to protrude outward. The presser ring 64 is made of, for example, titanium having excellent corrosion resistance against acid and alkali and sufficient rigidity, and the spacer 65 is made of a material having a low friction coefficient, for example, so that the presser ring 64 can rotate smoothly. It is composed of PTFE.

  Located on the outer side of the presser ring 64, the first holding member 54 is provided with inverted L-shaped clampers 74 having protrusions protruding inward at equal intervals along the circumferential direction. . On the other hand, a projecting portion 64 b that protrudes outward is provided at a position facing the clamper 74 along the circumferential direction of the presser ring 64. The lower surface of the inwardly projecting portion of the clamper 74 and the upper surface of the protruding portion 64a of the presser ring 64 are tapered surfaces that are inclined in opposite directions along the rotational direction. At a plurality of locations (for example, 3 locations) along the circumferential direction of the presser ring 64, potches 64a projecting upward are provided. Thereby, the presser ring 64 can be rotated by rotating a rotary pin (not shown) and pushing the potch 64a from the side.

  Thus, with the second holding member 58 open, the substrate W is inserted into the center of the first holding member 54, the second holding member 58 is closed via the hinge 56, and the presser ring 64 is rotated clockwise. Then, the protrusion 64b of the presser ring 64 is slid into the inner projecting part of the clamper 74, whereby the first holding member 54 and the first holding member 54 are connected to each other through the tapered surfaces provided on the presser ring 64 and the clamper 74, respectively. The two holding members 58 are tightened and locked together, and the presser ring 64 is rotated counterclockwise so that the protrusion 64b of the presser ring 64 is removed from the reverse L-shaped clamper 74, thereby releasing the lock. ing. Then, when the second holding member 58 is locked in this way, the lower end of the lower protruding portion on the inner peripheral surface side of the substrate side sealing member 66 is placed on the outer peripheral portion of the surface of the substrate W held by the substrate holder 18. In 68, the lower end of the lower projecting portion on the outer peripheral side is in pressure contact with the surface of the first holding member 54, and the sealing members 66 and 68 are pressed uniformly to seal them.

Thus, when the substrate W is held by the substrate holder 18, as shown in FIG. 5, the inside of the substrate holder 18 is sealed with the substrate sealing member 66 on the inner peripheral side and the holder side sealing member 68 on the outer peripheral side. and the holder-side internal space R ₁ is formed. The holder-side internal space R ₁ communicates with the substrate-side internal space R ₂ formed between the substrate holder 18 and the substrate W, whereby the holder side communicates with each other between the substrate holder 18 and the substrate. sealed internal space R and an internal space R ₁ and the substrate-side internal space R ₂ Metropolitan is formed.

  At the center of the first holding member 54, a protrusion 82 protrudes in a ring shape in accordance with the size of the substrate W, and the surface of the first holding member 54 abuts on the outer peripheral portion of the substrate W to form a support surface 80 that supports the substrate W. A recess 84 is provided at a predetermined position along the circumferential direction of the protrusion 82.

  As shown in FIG. 3, a plurality (12 in the figure) of conductors (electrical contacts) 86 respectively connected to a plurality of wires extending from external contacts provided in the hand 90 are disposed in the respective recesses 84. When the substrate W is placed on the support surface 80 of the first holding member 54, the end portion of the conductor 86 has a spring property on the surface of the first holding member 54 on the side of the substrate W. It is exposed and comes into contact 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 the shape of a leaf spring, and has a contact portion that is located outside the board-side seal member 66 and projects inwardly in the shape of a leaf spring. 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 supported by the support surface 80 of the first holding member 54. It is comprised so that it may contact elastically with the outer peripheral surface of the board | substrate W supported on the top.

  The second holding member 58 is opened and closed by the weight of a 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 a cylinder is provided at a position facing the through hole 54 a when the substrate holder 18 is placed on the substrate attaching / detaching portion 20. As a result, the cylinder rod is extended, the second holding member 58 is opened by pushing the seal holder 62 of the second holding member 58 upward with the pressing rod through the through hole 54a, and the cylinder rod is contracted, so that the second The holding member 58 is closed by its own weight.

  A pair of substantially T-shaped hands 90 are connected to the end portion of the first holding member 54 of the substrate holder 18 as a support portion when the substrate holder 18 is transported or supported by hanging. In the stocker 24, the protruding end portion of the hand 90 is hooked on the upper surface of the peripheral wall so that the hand 90 is vertically suspended and held, and the hand 90 of the substrate holder 18 that is suspended and held is held by the substrate holder transport device 40. The substrate holder 18 is conveyed by being gripped by the transporter 42 or 44. Note that the substrate holder 18 is suspended and held on the peripheral walls via the hand 90 also in the pre-wet tank 26, the pre-soak tank 28, the washing tanks 30a and 30b, the blow tank 32, and the plating tank 34.

Inside the first holding member 54, as schematically shown in FIG. 6, when the substrate W is held by the substrate holder 18, the substrate-side internal space R ₂ formed between the substrate holder 18 and the substrate W is formed. An internal passage 100 is formed which is sealed (sealed) by the seal members 66 and 68 and communicates with the internal space R formed between the substrate holder 18 and the substrate W. As shown in FIGS. 2 and 3, the internal passage 100 is connected to a suction port 102 provided in the hand 90.

  On the other hand, as schematically shown in FIG. 6, the substrate attaching / detaching portion 20 includes a seal ring 104, and the suction connected to the suction port 102 of the hand 90 through the seal ring 104 in a sealed state. A joint 106 is provided. The suction joint 106 is connected to an actuator 108 such as an air cylinder disposed at a predetermined position of the board attaching / detaching portion 20 via a connecting plate 110. As a result, when the leakage inspection is performed on the substrate holder 18 holding the substrate W, the actuator 108 is driven to connect the suction joint 106 to the suction port 102 provided in the hand 90. In other cases, the hand of the suction joint 106 is connected. The connection of the suction joint 106 to the suction port 102 provided at 90 is released.

  The suction joint 106 is connected to a suction line 114 extending from a vacuum source 112 such as a vacuum pump. The suction line 114 is provided with a pressure sensor 116 for measuring the pressure in the suction line 114 and a main opening / closing valve 118. Yes.

  Furthermore, a master container 120 that is guaranteed not to leak is provided, and a differential pressure inspection line 122 extending from the master container 120 joins the suction line 114 upstream of the main on-off valve 118. On the suction line 114 and the differential pressure inspection line 122, on-off valves 124a and 124b are respectively installed on the upstream side of the merging point between them, and further on-off valves 124a on the upstream side of the on-off valves 124a and 124b. , 124b is provided with a differential pressure sensor 126 for measuring a differential pressure between the pressure in the internal space R and the pressure in the master container 120. Thus, a pressure change detection unit 128 that detects a pressure change in the internal space R when the internal space R is evacuated and sealed through the suction line 114 is configured.

  Thus, the pressure change in the internal space R is detected using the differential pressure sensor 126 that measures the differential pressure between the pressure in the internal space R and the pressure in the master container 120 when the on-off valves 124a and 124b are closed. By doing so, a minute pressure change in the internal space can be detected more accurately as compared with the case where the pressure change in the internal space is directly measured using the pressure sensor.

  A bypass line 130 is provided which branches from the suction line 114 on the upstream side of the on-off valve 124 a and joins the suction line 114 between the on-off valve 124 a and the main on-off valve 118. The bypass line 130 is provided with on / off valves 132a and 132b, and a tracer gas tester 138 having a tester main body 136 having a tracer gas sensor 134 is installed at a position sandwiched between the on / off valves 132a and 132b. Connected to 136 is an atmospheric measurement hose 140 having an on-off valve 139. Accordingly, the tracer gas sensor 134 of the tracer gas tester 138 detects whether or not the tracer gas is contained in the air (gas) flowing along the bypass line 130.

  As shown in FIG. 7, a bottomed cylindrical seal case 142 that opens downward is disposed in the substrate attaching / detaching portion 20 so as to be movable up and down and retracted, and on the lower surface side of the seal case 142, the seal case 142 is lowered. Accordingly, a tracer gas seal member 146 that presses against the surface of the first holding member 54 of the substrate holder 18 along a seal line 144 indicated by a two-dot chain line in FIG. A cut seal member 148 that is pressed against the surface of the seal holder 62 of the holding member 58 to seal (seal) it is attached.

As a result, the seal case 142 in the retracted position is moved to a position directly above the substrate holder 18 and then lowered so that the tracer gas seal member 146 is held on the surface of the first holding member 54 and the cut seal member 148 is held second. A holder-side seal member 68 that seals between the first holding member 54 and the second holding member 58 is provided between the substrate holder 18 and the seal case 142 by being brought into pressure contact with the surface of the seal holder 62 of the member 58. Two sealed spaces are formed: a holder-side sealed space S ₁ that is inside, and a substrate-side sealed space S ₂ that has a substrate-side sealing member 66 that is in pressure contact with the outer periphery of the substrate W and seals the outer periphery. .

And, in this example, the tracer gas inlet 150a for introducing a tracer gas individually to the holder-side hermetic space S ₁ and the substrate-side hermetic space S _2, 150b are provided, respectively. That is, the tracer gas inlet 150a for introducing a tracer gas into the holder-side hermetic space _{S 1,} the gas fitting 154a and tracer gas cylinder attached to the gas supply port 152a communicating with the holder-side hermetic space _{S 1} which is provided in the seal case 142 156a A gas supply line 158a is connected to the gas supply line 158a, and a pressure regulating valve 160a and an open / close valve 162a are installed along the gas flow direction in the gas supply line 158a.

An air supply line 166a extending from the air supply source 164a and provided with an on-off valve 168a is connected to the gas supply line 158a on the downstream side of the on-off valve 162a. Further, the gas exhaust port 170a communicating with the holder-side hermetic space _{S 1} which is provided in the seal case 142, a gas exhaust line 174a which is installed off valve 172a is connected.

Thus, both open the on-off valve 172a for opening and closing valve 162a and the gas exhaust line 174a of the gas supply line 158a, a tracer gas is supplied to the inside of the holder-side hermetic space _{S 1,} Tokoro inside the holder-side hermetic space _{S 1} close valve 172a of the opening and closing valve 162a and the gas exhaust line 174a of the gas supply line 158a in both closed at the time the determination of the tracer gas is Tasa supplied, enclosing a tracer gas into the holder-side hermetic space S _1. Then, by opening the on-off valve 172a for opening and closing valve 168a and the gas exhaust line 174a of the air supply line 166a together, introducing air into the holder-side hermetic space _{S 1,} the interior of the tracer gas in the holder-side hermetic space _{S 1} Is discharged.

Incidentally, the tracer gas inlet 150b for introducing a tracer gas to the substrate side hermetic space S _2, since it has substantially the same configuration as the tracer gas inlet 150a for introducing a tracer gas into the holder-side hermetic space S _1, Corresponding members are denoted by reference numerals in which the Roman letter a is replaced with the Roman letter b, and redundant description is omitted. The gas supply port 152b and the gas exhaust port 170b is communicated with the substrate side hermetic space _{S 2.}

  In this example, helium gas is used as the tracer gas, which is lighter than air and is only 5 ppm in the air, so that it can be easily distinguished from other gases. The tracer gas tester 138 is a G-FINE helium leak tester (Cosmo Instruments Co., Ltd.). Use). Thus, according to this example, a leak of 0.0006 mL / min to 1000 mL / min of helium gas (tracer gas) is detected. If a leak of helium gas of 0.1 cc / min is detected, it is detected in 11 seconds. Can do.

As the tracer gas, a safe and clean non-flammable hydrogen gas of 5% + nitrogen gas of 95% (diluted hydrogen: H ₂ + N ₂ ) may be used. This gas is cheaper than helium gas, is stably supplied as a general industrial gas, has excellent diffusibility, and quick recovery, and has a low background concentration of 0.5 ppm. Further, argon gas heavier than air (1.784 g / L, 1.38 times the air ratio) may be used as the tracer gas. Argon gas is contained in air in an amount of 0.93 vol%.

  A series of plating processes performed by the plating apparatus configured as described above will be described. First, 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.

  In the substrate attaching / detaching unit 20, the two substrate holders 18 accommodated in the stocker 24 are simultaneously held by the first transporter 42 of the substrate holder transporting device 40 and transported 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 cylinder is operated to change the first position of the substrate holder 18. 2 Keep the holding member 58 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, the cylinder is operated reversely to close the second holding member 58, and thereafter, the substrate is attached above the substrate attaching / detaching unit 20. The second holding member 58 is locked by the lock / unlock mechanism. 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, and then the mounting plate. 52 is returned to the original position.

  As a result, the substrate W has the surface to be plated exposed from the opening of the substrate holder 18, and the outer peripheral portion of the substrate W is the substrate-side seal member 66, and the first holding member 54 and the second holding member. 58 is sealed (sealed) by the holder-side seal member 68 so that the plating solution does not enter, and is electrically connected to the plurality of electrical contacts 88 at portions where the plating solution is not touched by the seal members 66 and 68. To be fixed. Here, wiring is connected from the electrical contact 88 to the hand 90 of the substrate holder 18, and power can be supplied to the seed layer of the substrate by connecting a power source to the portion of the hand 90.

Next, the outer peripheral portion of the substrate W is the substrate-side seal member 66 of the substrate holder 18 holding the substrate W, and the holder-side seal member 68 is between the first holding member 54 and the second holding member 58, respectively. A first stage leakage inspection is performed before the plating process for determining whether or not each is sealed (sealed) so as not to enter. The processing flow of the first stage leakage inspection is shown in the upper part (steps 1 to 4) of FIG. That is, as shown in FIG. 6, the suction joint 106 is connected to the suction port 102 of the hand 90 of the substrate holder 18 and only the main on-off valve 118 and the on-off valve 124a of the suction line 114 are opened, and the internal space R (holder side the internal space R ₁ and the substrate-side internal space R ₂₎ by vacuum suction (step 1), that a predetermined time has elapsed (e.g., 2 seconds), for example by measuring with a timer (step 2), the inner space after a certain period of time It is inspected whether or not the inside of R reaches a predetermined vacuum pressure (step 3). The pressure in the internal space R is measured by the pressure sensor 116.

  When the inside space R does not reach a predetermined vacuum pressure within a predetermined period, for example, the substrate W is not held by the substrate holder 18, the seal members 66 and 68 are not assembled to the substrate holder 18, Alternatively, leakage due to an abnormality such as an obvious operation error or poor maintenance such as incomplete assembly of the seal members 66 and 68 to the seal holder 62 or a serious inconvenience in the seal members 66 and 68 occurs. It is determined that it occurs (failed to the first stage leakage inspection), and processing for the abnormality is performed (step 4). For example, when the substrate W is not held by the substrate holder 18, there may be a problem with the plating apparatus itself, so the plating apparatus is stopped and inspected. When the substrate W is held by the substrate holder 18, for example, the substrate holder 18 is collected and inspected.

  In this way, the first stage leak inspection reduces the burden on the following second stage leak inspection by quickly and promptly detecting the occurrence of plating solution leaks due to obvious operational mistakes or poor maintenance. be able to.

  The second stage leakage inspection is performed on the substrate holder 18 that has reached the predetermined vacuum pressure within the internal space R within a predetermined period and passed the first stage leakage inspection. The processing flow of the second stage leakage inspection is shown in the lower part of FIG. 8 (steps 5 to 8). That is, first, as described above, with the suction joint 106 connected to the suction port 102 of the substrate holder 18 hand 90, the main on-off valve 118 and the on-off valve 124a of the suction line 114, and the on-off valve 124b of the differential pressure inspection line 122. (Step 5), the internal space R and the master container 120 are simultaneously vacuumed so that the internal space R and the master container 120 have the same pressure. Then, the main on-off valve 118 and the on-off valve 124a of the suction line 114 and the on-off valve 124b of the differential pressure inspection line 122 are closed and left for a certain time (for example, 5 seconds). (Step 6), whether or not the differential pressure between the pressure in the internal space R and the pressure in the master container 120 changes to a specified value or more (that is, the degree of vacuum decreases) A so-called vacuum standing method (build-up test), which is measured by the differential pressure sensor 126, is performed (step 7). In this way, by carrying out the vacuum standing method (build-up test), the pressure change in the internal space can be further reduced compared to the case of directly measuring the pressure change in the internal space using a pressure sensor. It can be detected accurately.

  In this example, the pressure change detection unit 128 using the differential pressure measurement method using the differential pressure sensor 126 is used to measure the pressure change in the internal space R. In this way, the pressure change detection unit is separately provided. Instead, the pressure sensor 116 may also serve as a pressure change detection unit, and the pressure sensor 116 may directly measure the pressure change in the internal space R.

  When the pressure difference between the pressure in the internal space R and the pressure in the master container 120 changes to a specified value or more, the sealing by the sealing members 66 and 68 of the substrate holder 18 is incomplete (not suitable for the second stage leakage inspection). Pass). The reason why the sealing by the sealing members 66 and 68 is incomplete is considered as follows.

(1) The substrate W was not held at the correct position of the substrate holder 18.
(2) The surface of the resist formed on the surface of the substrate W (applied to the surface of the substrate for masking the portion that should not be plated) has irregularities, or the resist just below the seal member is chipped. The resist was not normal because the outer diameter of the resist was small, the outer diameter of the resist and the outer diameter of the substrate were not concentric.
(3) The seal members 66 and 68 were damaged because the sheet surfaces of the seal members 66 and 68 were damaged, or the seal members 66 and 68 lost elasticity due to the influence of the plating solution.
(4) The resist of the substrate processed last time peeled off and adhered to the substrate-side seal member 66.

  Then, for example, the following treatment is performed on the substrate holder 18 that has failed the second stage leakage inspection in this way (step 8).

(1) The substrate W is once taken out from the substrate holder 18, and the substrate W is changed to a position where the resist on the surface of the substrate W and the substrate-side seal member 66 contact each other, for example, by rotating the substrate W by 180 °. Hold again at 18.
(2) Remove the substrate W from the substrate holder 18 and replace it with the next substrate. In this case, the substrate W taken out from the substrate holder 18 is collected, and the state of the resist on the substrate W is mainly inspected.
(3) Replace and collect the substrate holder 18 for inspection. Assuming such a case, it is desirable to store a spare substrate holder in the plating apparatus, and a plating apparatus having a structure that allows the substrate holder to be taken in and out even during operation may be used.

Next, an example in which the third stage leakage inspection is performed following the second stage leakage inspection will be described below.
First, as shown in FIG. 7, the seal case 142 in the retracted position is moved to a position just above the substrate holder 18 holding the substrate W to be inspected and lowered, and the tracer gas seal member 146 of the seal case 142 is moved to the substrate. The cut seal member 148 is pressed to a position along the seal line 144 of the first holding member 54 of the holder 18 so that the surface of the seal holder 62 of the second holding member 58 is lightly touched. Thus, a holder side sealed space S ₁ and a substrate side sealed space S ₂ sealed (sealed) by the tracer gas seal member 146 and the cut seal member 148 are formed between the substrate holder 18 and the seal case 1472.

  Since the third stage leakage inspection is performed directly under the lock / unlock mechanism, the seal case 142 is retracted to a position retracted from directly under the lock / unlock mechanism except during the inspection, and the substrate holder is inspected during the inspection. 18 and inserted into the space between the lock / unlock mechanism. The seal case 142 is moved by a seal case moving mechanism (not shown).

In this state, first, carrying out the third stage leakage inspection of the holder-side hermetic space S _1. That is, open only on-off valve 172a for opening and closing valve 162a and a gas exhaust line 1174a of the gas supply line 158a of the tracer gas inlet 150a, and supplies a tracer gas such as helium gas in the interior of the holder-side hermetic space _{S 1.} Then, when a predetermined amount of tracer gas to the holder-side hermetic space _{S 1} is supplied, closing both the opening and closing valve 172a of the on-off valve 162a and the gas exhaust line 174a of the gas supply line 158a. In this way, in a state of enclosing the tracer gas in the holder-side hermetic space S ₁ in the same manner as described above, the suction port 102 of the substrate holder 18 hand 90 is connected to a suction fitting 106, the opening and closing valve 132a of the bypass line 130 132b and the main on-off valve 118 of the suction line 114 are opened, the inside space R is vacuum-sucked, and this vacuum-suctioned air (gas) is collected in the tester body 136 of the tracer gas tester 138.

Then, the tracer gas sensor 134 measures whether or not the air (gas) collected in the tester main body 136 contains tracer gas, in this example helium gas. Since only 5 ppm of helium gas exists in nature, a difference in helium gas concentration is obtained between the air (gas) in which helium gas is contained and air in the natural world. Can be measured. When the tracer gas (helium gas) is included in the air collected in the tester body 136 (gas), located on the holder side hermetic space S _1, attached to the second holding member 58 of the substrate holder 18 It is determined that the sealing performance of the holder-side seal member 68 is incomplete, and there is a leak between the holder-side seal member 68 and the first holding member 54 (third stage leak test failed).

  In this way, by utilizing the leakage of the tracer gas and determining that a leak occurs between the holder-side seal member 68 and the first holding member 54, the holder-side seal member 68 and the first holding member 54 Even if a very small amount of plating solution leaks in the meantime, this can be reliably detected in advance. This is the same even when a very small amount of plating solution leaks between the substrate-side sealing member 66 and the surface of the substrate W described below.

Then, in much the same way as for the holder-side hermetic space S ₁ described above, with the inside supplied sealed tracer gas (helium gas) of the substrate-side hermetic space S _2, and vacuum suction to the internal space R The vacuum sucked air (gas) is collected in the tester body 136 of the tracer gas tester 138, and the tracer gas sensor determines whether or not the tracer gas (helium gas) is contained in the air (gas) collected in the tester body 136. Measure at 134. When the tracer gas (helium gas) is included in the air collected in the tester body 136 (gas), located on the substrate side closed space S _2, attached to the second holding member 58 of the substrate holder 18 It is determined that the sealing performance of the substrate-side seal member 66 is incomplete and there is a leak between the substrate-side seal member 66 and the surface of the substrate W (failed third stage leak test).

When it is determined that there is a leak between the holder-side seal member 68 and the first holding member 54 or there is a leak between the substrate-side seal member 66 and the surface of the substrate W, the second stage described above. Take measures according to the failure of the leak test. In this way, by performing the third-stage leakage inspection of the holder-side sealed space S ₁ and the substrate-side sealed space S ₂ individually, leakage occurs at the substrate-side seal member 66 or at the holder-side seal member 68. It is possible to determine whether or not it occurs and take appropriate measures for the place where the leak occurs.

  According to this example, by conducting the first stage leak inspection that can be done in a relatively short time, by quickly and promptly detecting the leakage of the plating solution due to obvious operational mistakes or poor maintenance, By reducing the load on the second-stage leakage inspection and then performing the second-stage leakage inspection, a serious defect related to the sealing performance of the sealing members 66 and 68 of the substrate holder 18 can be found reliably and quickly. Appropriate measures can be taken for leaks. Then, if necessary, a third stage leak inspection that requires a relatively long time is performed on the substrate holder 18 that has passed the second stage leak inspection, so that the seal members 66 and 68 have an extremely fine leak. Even if it occurs, this can be reliably detected.

  This third stage leakage inspection need not be performed every time the substrate W is held by the substrate holder 18. This is because the state of the sealing members 66 and 68 of the substrate and the substrate holder 18 rarely changes dramatically. In addition, since the third stage leakage inspection generally requires a long time, if the third stage leakage inspection is frequently performed, the throughput decreases. For this reason, the third stage leak inspection for confirming the state of each substrate holder alone, that is, the first stage leak inspection and the second stage is performed as an off-line inspection that does not affect production periodically or after the start of operation or after the end of operation. It may be performed separately from the stage leak inspection. When performing leak inspection (third-stage leak inspection) by off-line inspection, a dummy substrate (with a resist applied) is used to accurately inspect the state of the substrate holder by eliminating the influence of the resist formed on the substrate surface. It is preferable to perform a leakage inspection on each substrate holder holding a dummy substrate. This does not reduce the throughput. The dummy substrate is supplied to the substrate holder 18 from, for example, a cassette 10 containing a dummy substrate set on the cassette table 12 or a dummy substrate cassette containing a dummy substrate provided in the apparatus.

In the above example, the holder-side hermetic space S ₁ and is for both space of the substrate-side hermetic space S ₂ has implemented a third stage leakage test, the holder-side hermetic space S ₁ and the substrate-side hermetic space S ₂ A third stage leak test may be performed on one of the spaces. For example implemented third stage leakage test on the holder side hermetic space S _1, the sealing property of the holder-side sealing member 68 attached to the second holding member 58 of the substrate holder 18 is incomplete, and the holder-side sealing member 68 at the stage where it is determined that there is a leak (third stage leakage inspection failure) between the first holding member 54, may be omitted third stage leakage test for the substrate-side hermetic space S _2.

  The plating process is performed on the substrate held by the substrate holder 18 that has passed the leakage inspection before the plating process. For a substrate held by the substrate holder 18 that has failed the leak inspection before the plating process, the substrate holder 18 is opened, and the substrate held by the substrate holder 18 is placed in the cassette 10 of the cassette table 12. return. Then, the substrate holder 18 is gripped by the first transporter 42 of the substrate holder transport device 40, returned to the stocker 24, and is not used as it is. Then, for example, after the operation is completed, the substrate holder 18 is taken out from the stocker 24 and appropriate measures are taken.

  Thereby, it is determined whether or not the outer peripheral portion of the substrate W is properly sealed by the substrate-side seal member 66 and the space between the first holding member 54 and the second holding member 58 is properly sealed by the holder-side seal member 68, respectively. A series of plating processes including a leak inspection before the plating process for all the substrate holders 18 can be performed systematically and continuously.

  At the same time or before and after the leak inspection before the plating process, a sensor for confirming the contact state between the substrate provided in the substrate holder 18 and the electrical contact 88 is used to determine whether or not the contact state is defective. You may make it perform the process similar to the board | substrate holder which failed the leak test | inspection before a metal-plating process with respect to the board | substrate holder determined to be in a bad state.

  The plating process for the substrate held by the substrate holder 18 that has passed the leakage inspection before the plating process will be described below.

  The substrate holder 18 holding the substrate that has passed the leakage inspection before the plating process is held by the first transporter 42 of the substrate holder transport device 40, transported to the pre-wet tank 26, and lowered to thereby hold the substrate. 18 is immersed in the pre-wet liquid in the pre-wet tank 26. Note that, as described above, the substrate holder 18 that has been disqualified from the leakage inspection before the plating process and is no longer used is returned to the stocker 24 and is not transported to the pre-wet tank 26.

  The substrate holder 18 holding the substrate that has passed the leakage inspection before the plating process is transported to the stocker 24 and suspended (temporarily placed) in a vertical state, and the substrate holder 18 temporarily placed in the stocker 24 is held. You may make it convey to the pre-wet tank 26. FIG.

  Although not shown, instead of the substrate attaching / detaching unit 20 for horizontally placing the two substrate holders 18, the two substrate holders conveyed by the first transporter 42 are vertically (or slightly inclined slightly from the vertical). The fixing station for supporting the substrate holder may be provided, and the fixing station holding the substrate holder vertically may be rotated by 90 ° to bring the substrate holder into a horizontal state.

  Also, in this example, an example in which one lock / unlock mechanism is provided is shown, but the lock / unlock of two substrate holders provided with two lock / unlock mechanisms and arranged adjacent to each other is shown. Locking and unlocking may be performed simultaneously by a locking mechanism.

  Next, the substrate holder 18 holding the substrate is transferred to the pre-soak tank 28 in the same manner as described above, and the oxide film on the substrate surface is etched in the pre-soak tank 28 to expose a clean metal surface. Further, the substrate holder 18 holding the substrate is transported to the first washing tank 30a in the same manner as described above, and the surface of the substrate is washed with pure water put in the first washing tank 30a.

  The substrate holder 18 holding the washed substrate is held by the second transporter 44 of the substrate holder transfer device 40, transferred to the plating tank 34 filled with the plating solution, and suspended and held in the plating cell 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 cell 38 of the plating tank 34 and suspend and hold it at a predetermined position.

  After the substrate holder 18 is suspended and held, a plating voltage is applied between an anode (not shown) in the plating cell 38 and the substrate W, and at the same time, the paddle driving device 46 reciprocates the paddle in parallel with the surface of the substrate. Then, the surface of the substrate is plated. At this time, the substrate holder 18 is suspended and fixed by the hand 90 on the upper part of the plating cell 38, and power is supplied to the seed layer or the like from the plating power source through the conductor 86 and the electrical contact 88. Circulation of the plating solution from the overflow tank 36 to the plating cell 38 is basically always performed during the operation of the apparatus, and the temperature of the plating solution is kept constant by a constant temperature unit (not shown) in the circulation line.

  After the plating is finished, the application of the plating power supply and the paddle reciprocation are stopped, and the substrate holder 18 on which the substrate W after plating is mounted is held by the second transporter 44 of the substrate holder transport device 40, and the same as described above. Then, the substrate is transported to the second water washing tank 30b, and the surface of the substrate is washed with pure water put in the second water washing tank 30b.

Next, the substrate holder 18 on which the cleaned substrate W is mounted is transported to the blow tank 32 in the same manner as described above. Here, the substrate holder 18 and the substrate holder 18 are blown by blowing air or N ₂ gas. Water droplets adhering to the surface of the held substrate W are removed and dried.

  The second transporter 44 of the substrate holder transport device 40 repeats the above operation, and transfers the substrate holder 18 with the substrate on which plating has been completed to the blow tank 32.

  The first transporter 42 of the substrate holder transport device 40 holds the substrate holder 18 that has been plated and dried in the blow tank 32 and places it on the mounting plate 52 of the substrate attaching / detaching unit 20.

  Then, the second holding member 58 of the substrate holder 18 located on the center side is unlocked via a lock / unlock mechanism, and the cylinder is operated to open the second holding member 58. At this time, a spring member (not shown) different from the electrical contact 88 is provided on the second holding member 58 of the substrate holder 18, and the second holding member 58 is opened while the substrate W is stuck to the second holding member 58. It is desirable to prevent this. Thereafter, the plated substrate W in the substrate holder 18 is taken out by the substrate transfer device 22 and carried to the spin rinse dryer 16, washed with pure water, and then spin dried (drained) by the high speed rotation of the spin rinse dryer 16. Then, the substrate after spin drying is returned to the cassette 10 by the substrate transfer device 22.

  And after returning the board | substrate with which one board | substrate holder 18 was mounted | worn to the cassette 10, or in parallel with this, the mounting plate 52 was slid to the horizontal direction, and was similarly mounted | worn with the other board | substrate holder 18. The substrate is spin rinsed and returned to the cassette 10.

  A substrate W 18 to be newly processed by the substrate transfer device 22 is mounted on the substrate holder 18 that has taken out the substrate, and continuous processing is performed. If there is no new substrate W to be processed, the substrate holder 18 that has taken out the substrate is held by the first transporter 42 of the substrate holder transport device 40 and returned to a predetermined location in the stocker 24.

  Then, all the substrates are taken out from the substrate holder 18, spin-dried and returned to the cassette 10 to complete the operation. In this manner, all the substrates are plated, washed with the spin rinse dryer 16 and dried, and the substrate holder 18 is returned to a predetermined location of the stocker 24 to complete a series of operations.

  FIG. 9 is a diagram schematically showing a main part of a plating apparatus according to another embodiment of the present invention. The differences from the above-described plating apparatus of this example are as follows. That is, the seal case 142 without the sorting seal member 148 (see FIG. 6) is used, and the tracer gas seal member 146 of the seal case 142 is moved along the seal line 144 (see FIG. 3). A holder-side seal member 68 that seals between the first holding member 54 and the second holding member 58 between the seal case 142 and the substrate holder 18 when pressed against the surface of the first holding member 54; A sealed space S having a substrate-side sealing member 66 for sealing the outer peripheral portion by pressure contact with the outer peripheral portion is formed, and a single tracer gas introducing portion 150 for introducing the tracer gas into the sealed space S is provided. There is in point.

Single tracer gas inlet 150 for introducing a tracer gas into the closed space S, since they have almost the same structure as tracer gas inlet 150a for introducing a tracer gas into the holder-side hermetic space S ₁ of the above , Corresponding members are denoted by reference numerals with the Roman letter a omitted, and redundant description is omitted. The gas supply port 152 and the gas exhaust port 170 communicate with the sealed space S.

  According to this example, the third stage leakage inspection is performed as follows. That is, the tracer gas seal member 146 of the seal case 142 is pressed to such an extent that it is lightly in contact with the position along the seal line 144 (see FIG. 3) of the first holding member 54 of the substrate holder 18. A sealed space S sealed (sealed) by a tracer gas seal member 146 is formed between the first and second 1472. Similarly to the above, with the tracer gas (helium gas) supplied and sealed in the sealed space S, the interior space R is vacuum-sucked, and the vacuum-sucked air (gas) is supplied to the tracer gas tester 138. The tracer gas sensor 134 measures whether or not the tracer gas (helium gas) is contained in the air (gas) collected in the tester main body 136 and collected in the tester main body 136.

  When the tracer gas (helium gas) is included in the air (gas) collected in the tester main body 136, it is attached to the second holding member 58 of the substrate holder 18 located in the sealed space S. The sealing property of at least one of the substrate side seal member 66 or the holder side seal member 68 is incomplete, and between the holder side seal member 68 and the first holding member 54 or between the substrate side seal member 66 and the surface of the substrate W. It is determined that there is a leak in at least one of them (failed third stage leak test).

  In this example, it is not possible to specify which of the substrate side sealing member 66 and the holder side sealing member 68 attached to the second holding member 58 of the substrate holder 18 causes the leakage, but it is shorter. The third stage leak inspection of the substrate holder 18 can be completed in time.

  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 24 Stocker 26 Pre-wet tank 28 Pre-soak tank 30a, 30b Washing tank 32 Blow tank 34 Plating tank 36 Overflow tank 54 First holding member (fixed holding member)
58 Second holding member (movable holding member)
62 Seal holder 64 Presser ring 66 Substrate side seal member 68 Holder side seal member 74 Clamper 90 Hand 100 Internal passage 102 Suction port 106 Suction joint 112 Vacuum source 114 Suction line 116 Pressure sensor 120 Master container 126 Differential pressure sensor 128 Pressure change detection unit 130 Bypass line 134 Tracer gas sensor 136 Tester body 138 Tracer gas tester 142 Seal case 144 Seal line 146 Tracer gas seal member 148 Cut seal member 150, 150a, 150b Tracer gas introduction part 154, 154a, 154b Gas joint 156, 156a, 156b Tracer gas cylinders 158, 158a, 158b Gas supply lines 166, 166a, 166b Air supply lines 170, 170a, 170b Gas exhaust ports 174,174a, 174b gas exhaust line _{R 1} holder-side internal space _{R 2} substrate-side internal space R inside space _{S 1} holder side hermetic space _{S 2} substrate side closed space S enclosed space

Claims (4)

A method for performing a leak test on a substrate holder comprising a first holding member and a second holding member having an opening,
While supporting one surface of the substrate with the first holding member, the second holding member is brought into contact with the other surface of the substrate, and the other surface of the substrate is exposed from the opening of the second holding member. Holding the substrate with the substrate holder in a state
When the substrate is held by the substrate holder, the first protrusion of the second holding member seals between the first holding member and the second holding member, and the second protrusion of the second holding member By sealing the outer periphery of the substrate, an internal space is formed in the substrate holder by the first holding member, the second holding member, and the substrate,
The inside of the internal space is evacuated and a first stage leak inspection is performed to check whether the internal space reaches a predetermined vacuum pressure after a predetermined time to inspect the sealing performance of the first protrusion and the second protrusion. And
With respect to the substrate holder holding the substrate that has passed the first stage leakage inspection, the internal space is sealed after the internal space is evacuated, and the pressure in the internal space changes to a predetermined value or more within a predetermined time. Performing a second-stage leak test to check whether or not to perform a further check on the sealing performance of the first protrusion and the second protrusion.   Whether or not the pressure in the internal space changes to a predetermined value or more within a predetermined time is sealed by simultaneously evacuating the pressure after sealing in the internal space and evacuating the internal space. The method according to claim 1, wherein a pressure difference from the pressure in the master container free from gas leakage is measured by a differential pressure sensor and inspected.   A seal case is disposed so as to cover the surface exposed from the opening of the substrate held by the substrate holder that has passed the second stage leakage inspection, and between the first holding member of the substrate holder and the seal case The sealed space is formed between the substrate holder and the seal case, and the internal space is evacuated while introducing the tracer gas into the sealed space, and the air sucked from the internal space 3. The method according to claim 1, wherein a third stage leakage inspection for inspecting whether tracer gas is contained therein is performed to further inspect the sealing performance of the first protrusion and the second protrusion. The method described.   By sealing between the second holding member of the substrate holder and the seal case, the sealed space is formed into a substrate-side sealed space in which the second protrusion is disposed, and the first protrusion is The method according to claim 3, wherein the third stage leakage test is performed on at least one of the two sealed spaces by dividing the sealed space into two sealed spaces on the holder side disposed inside.

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