The present invention relates to a substrate holder that holds a substrate such as a semiconductor wafer in a substrate plating device, a substrate plating device provided with the substrate holder, and an electrical contact.
On the surfaces of substrates such as a semiconductor wafer, a printed circuit board and the like, wiring and bumps (protruding electrodes) are to be formed. In order to form wiring and bumps (protruding electrodes) on a substrate, for example, an electrolytic plating method, a vapor deposition method, a printing method, a ball-bump method and the like are employed. Among these, the electrolytic plating method that enables microfabrication and stabilization of performance is widely employed.
The electrolytic plating method immerses a substrate in a plating solution and applies an electric current to form a plate on a surface of the substrate. A substrate plating device employing the electrolytic plating method is exemplified by a device enabling plating on a surface of a substrate through immersing in a plating solution a substrate holder holding the substrate with only the surface of the substrate (face to be plated) being exposed and applying an electric current to the substrate.
With regard to such a substrate plating device and a substrate holder, Patent Literature 1 identified below discloses a substrate holder including: a first holding member having a supporting face that supports a substrate; and a second holding member that holds the substrate in a sandwiched manner with the first holding member, in which the first holding member has a plate-like first contact arranged along a circumference of a supporting face, and the second holding member has a second contact including a first end portion in contact with the substrate arranged on the supporting face and a second end portion in contact with the first contact, the second end portion being configured to be in plastic contact with the first contact when the substrate is held by the first holding member and the second holding member. This substrate holder ensures the second contact to be in contact with the first contact without requiring the first contact and the second contact to be formed with an expensive spring material.
Although the substrate holder exemplified in the above-cited Patent Literature 1 is capable of holding a round substrate, in recent years an increase in size of substrates is accompanied by emergence of rectangular substrates and the like, leading to development of a substrate holder capable of holding a rectangular substrate (see Patent Literature 2 identified below). Furthermore, a substrate holder permitting plating on both faces of a substrate has also been developed (see Patent Literature 3 identified below).
Patent Literature 1: Japanese Patent Laid-Open No. 2017-203178
Patent Literature 2: Japanese Patent Laid-Open No. 2018-40045
Patent Literature 3: Japanese Patent Laid-Open No. 2019-7075
A substrate holder, for example as shown in Patent Literature 1, holds a substrate in a sandwiched manner between two holding members, and allows plating on the substrate through application of an electric current in a state in which a second contact provided in one holding member is in contact with the substrate and also in contact with a first contact in the other holding member upon holding.
Such electrical contacts may cause contact failure due to a stain or the like in a region to be in contact with the substrate. In addition, a space formed by the two holding members is hermetically sealed during plating and such a structure inhibits a plating solution from being applied to an electrical contact within the space, yet the plating solution may be splashed and adhere to the contact upon opening of the holding members, leading to a current-carrying failure.
In this regard, the electrical contact is replaced on a regular basis, or when a failure occurs. The electrical contact, for example as shown in
Furthermore, as disclosed in Patent Literature 1, when the substrate is round, the holding members are also round, and a contact is to be fixed onto an inner peripheral face thereof. Having to fix the plate-like contact along an arc-like concave face has made the operation more difficult.
Given the foregoing, a principal objective of the present invention is to provide a substrate holder for plating on a surface of a substrate, provided with an electrical contact that is easy to replace.
A substrate holder for plating on a surface of a substrate according to one mode of the present invention includes: a first holding member; a second holding member that has an opening portion for exposing the surface of the substrate and holds the substrate in a sandwiched manner with the first holding member; a plurality of engaging shaft portions each having a head portion in an expanded head shape at a tip end portion, provided in a circumferential direction of the second holding member; and an electrical contact having a contact portion to be in contact with an edge portion of the substrate, and having an engagement reception portion in a notch shape to be engaged with the adjacent engaging shaft portion for arrangement along a circumference of the opening portion of the second holding member.
By thus providing the plurality of engaging shaft portions each having the head portion in an expanded head shape at the tip end portion at predetermined intervals on the second holding member of the substrate holder, and attaching the electrical contact by engaging the engagement reception portion in a notch shape provided on the electrical contact with the engaging shaft portion, easy attachment of the electrical contact to the second holding member is enabled and a replacement operation is facilitated.
In the substrate holder according to the one mode, it is preferred that the engagement reception portion is configured as a notch in a curved concave shape. Such a configuration facilitates the engagement reception portion to be engaged with the engaging shaft portion, and in turn facilitates the replacement operation.
In the substrate holder according to the one mode, it is preferred that the electrical contact is provided with a hook piece portion in a hook shape to be engaged with an engagement groove provided in the second holding member. In addition to the engagement reception portion, the hook piece portion can also engage with the second holding member, enabling an increase in an engagement force.
In the substrate holder according to the one mode, it is preferred that: a hole portion is provided in the vicinity of the center of the electrical contact; and the electrical contact is fixed to the second holding member by inserting a fastening member into the hole portion and fastening the fastening member. Such a configuration enables the electrical contact to be reliably fixed to the second holding member with at least one fastening member such as a screw, enabling a convenient replacement operation compared to the conventional art.
In the substrate holder according to the one mode, it is preferred that the second holding member is formed of an electrically conductive metal. Such a configuration makes the second holding member electrically conductive, whereby an electric current applied to the second holding member can also be applied to the electrical contact, thus inhibiting a current-carrying failure and the like.
The substrate holder according to the one mode includes, on a side of the opening portion of the second holding member, an inner peripheral face curved in an inner-outer direction of the second holding member, and the electrical contact can be attached along the inner peripheral face. In such a configuration, the electrical contact is attached in a deflected state, enabling stable attachment along the inner peripheral face under the action of an elastic force.
In the substrate holder according to the one mode, the second holding member may be configured in a polygonal frame shape or a round frame shape. It can accept, in addition to a round substrate, a polygonal substrate such as a rectangular substrate, and the electrical contact can be attached to a substrate holder of any configuration.
The present invention is directed also to a substrate plating device provided with the substrate holder according to the one mode, a contact for the substrate holder, and an electrical contact attachment structure for the substrate holder.
Hereinafter, the substrate holder according to one embodiment of the present invention is described. However, the present invention is not limited to the embodiment.
A substrate holder 1 according to one embodiment of the present invention is used for holding a substrate W for plating on a surface of the substrate W in a substrate plating device and the like, as shown in
As the substrate plating device, a conventional device may be used. For example, the following substrate plating device 100 may be used.
In a rough explanation, as shown in
The substrate plating device 100 is further provided with a stocker 106, a prewetting tank 107, a presoaking tank 108, a first washing tank 109, a blow tank 110, a second washing tank 111, and a plating tank 112, and enables washing, etching and the like of the substrate W through conveyance of the substrate holder 1 from the prewetting tank 107 to the second washing tank 111, sequentially. Conveyance of the substrate holder 1 may be carried out by a substrate holder conveyor device 114.
The plating tank 112 is provided with a plurality of plating cells 113, each of which is configured to accommodate one substrate W and immerse the substrate W in the plating solution contained thereinside to apply a plate such as a copper plate on the surface of the substrate W.
In addition, the substrate holder conveyor device 114 is provided with a first transporter 115 and a second transporter 116, enabling the substrate holder 1 to be conveyed in a state of being oriented in a vertical direction.
An example of a plating process by the substrate plating device 100 is described.
First, one substrate is taken out from the hoop 101 storing the substrate W by means of the substrate conveyor device 105, and conveyed to the aligner 102. The aligner 102 aligns positions of an orientation flat, a notch, and the like in predetermined directions. The substrate W thus aligned in orientation by the aligner 102 is conveyed to the fixing unit 104 by the substrate conveyor device 105.
The substrate holder 1 accommodated in the stocker 106 is conveyed to the fixing unit 104 and then the substrate W is conveyed to the substrate holder 1 by the substrate conveyor device 105 to cause the substrate holder 1 to hold the substrate W.
Next, the substrate holder 1 holding the substrate W is conveyed sequentially to the prewetting tank 107, the presoaking tank 108, the first washing tank 109, and the plating tank 112 by the first transporter 115 and the second transporter 116, and stored in the plating cell 113 filled with the plating solution. The substrate holder 1 holding the substrate W is thus stored in each plating cell 113 in the plating tank 112.
In each plating cell 113, plating voltage is applied between an anode and the substrate W in the plating cell 113, to carry out plating on the surface of the substrate W.
After completion of plating, the substrate holder 1 holding the substrate thus plated is conveyed sequentially to the second washing tank 111 and the blow tank 110, and then the substrate holder 1 is conveyed to the fixing unit 104.
In the fixing unit 104, the substrate W thus processed is removed from the substrate holder 1 by the substrate conveyor device 105, and conveyed to and dried in the spin-rinse dryer 103. The substrate W thus dried is returned to the hoop 101 by the substrate conveyor device 105.
A plate can thus be applied to the substrate W held by the substrate holder 1.
As for a more detailed configuration of the substrate plating device 100, description in paragraphs [0011] to [0017] and the like of the Specification of Japanese Patent Application No. 2018-119875 filed by the present applicants may be referenced.
The substrate holder 1 is provided with the first holding member 2 and the second holding member 3 as shown in
The substrate holder 1 is configured such that the substrate W is sandwiched between the first holding member 2 and the second holding member 3, which are fixedly joined to hold the substrate W, and may be provided in the substrate plating device 100 illustrated in
The substrate W may be exemplified by a semiconductor substrate (wafer), a glass substrate, a printed circuit board and the like, and also includes a magnetic recording medium, a magnetic recording sensor, a mirror, an optical element, a micro-mechanical element, a partially-fabricated integrated circuit, and the like.
The first holding member 2 is also referred to as a fixed holding member, and is provided with: a body portion 21 that forms an outer face; a substrate mount table 22 that supports the substrate W placed thereon; a hanging ring 23 for fixing the second holding member 3; a hand portion 24 for suspending the substrate holder 1 upon immersion in the plating solution and the like; and an external contact 25 electrically connected to an external power source, as shown in
The body portion 21 is formed of a resin such as PTFE (polytetrafluoroethylene) and the like, and configured as a plate-like housing as shown in
The base plate 26 is formed of an electrically conductive metal such as stainless steel, configured in a round planar shape with a plurality of fan-shaped openings, and arranged on one end side (a lower end side in
The substrate mount table 22 is configured in a round planar shape as shown in
The hanging ring 23 is formed of an electrically conductive metal such as stainless steel, configured in a ring shape formed of a flat plate, and arranged inside a circumferential groove portion 21a provided along an outer edge of the substrate mount table 22 of the body portion 21 as shown in
The hanging ring 23 is provided with a plurality of through holes 23a as shown in
Note that, in the present embodiment, the hanging ring 23 is configured to be rotationally movable by moving a rod member 4 shown in
The hand portion 24 is provided on one end side (an upper end side in
The external contact 25 is connected to a conductive wire 25a linked to the base plate 26 as shown in
The second holding member 3 is also referred to as a movable holding member, and is configured in a round ring shape with an opening portion 3a as shown in
The second holding member 3 is provided with: a main body portion 31; an electrical contact 32 to be in contact with the edge portion of the substrate W; an upper seal portion 33 and a lower seal portion 34 that hermetically seal a space formed by the first holding member 2 and the second holding member 3 when the substrate is held; and the hanging pin 35, as shown in
The main body portion 31 is in a round ring shape with a laterally long rectangular cross-sectional shape as shown in
The main body portion 31 is formed of an electrically conductive metal such as stainless steel, aluminum, and the like, and is configured such that, when the substrate W is held, the hanging pin 35 provided on a lower face of the main body portion 31 comes into contact with the hanging ring 23 to be electrically connected to the base plate 26, the hanging ring 23, and the main body portion 31 as shown in
The inner peripheral face 31a of the main body portion 31 is formed to be substantially perpendicular to the upper face of the second holding member 3, such that the surface is a smooth surface and the electrical contact 32 can be arranged along this face. The inner peripheral face 31a is in a round shape in a planar view. By thus configuring the inner peripheral face 31a in a curved face shape curved in an inner-outer direction of the second holding member 3, an elastic force acts when the electrical contact 32 is arranged, whereby positional shift of the electrical contact 32 can be prevented.
In addition, a plurality of engaging shaft portions 36 are provided on the inner peripheral face 31a at substantially regular intervals, as shown in
In the present embodiment, the engaging shaft portion 36 is configured to have the shaft portion 36a in a round shaft shape and the head portion 36b in a round planar shape greater in diameter than the shaft portion 36a. More specifically, the engaging shaft portion 36 is formed of a flat head screw and fastened to a first fastening hole 31b 6provided on the inner peripheral face 31a.
Between the inner peripheral face 31a and the head portion 36b, a gap into which the electrical contact 32 can be inserted is provided as shown in
On the inner peripheral face 31a, a second fastening hole 31c is provided between the engaging shaft portions 36 as shown in
The plurality of hanging pins 35 protruding downward in a shaft-like shape are provided on the lower face of the main body portion 31 as shown in
The electrical contact 32 is to come into contact with the substrate W to apply an electric current. In the following description of the electrical contact 32, the side shown in
The electrical contact 32 is in a rectangular plate-like shape, more specifically in a laterally long rectangular plate-like shape. The thickness of the electrical contact 32 is not particularly limited, and such a thickness that the electrical contact 32 can be deflected to facilitate attachment or detachment with respect to the inner peripheral face 31a is preferred.
In the electrical contact 32: a contact portion 32a, in a comb teeth shape with a plurality of slits, to be in contact with the edge portion of the substrate W is provided on one longitudinal end portion side (upper side in
The contact portion 32a is a part to be in contact with the edge portion of the substrate W in a state in which the first holding member 2 and the second holding member 3 hold the substrate W, to permit an electric current to be applied to the substrate W as shown in
The engagement reception portion 32b is provided in the vicinity of the center in the height direction of the left and right side end portions of the electrical contact 32 as shown in
The shape of the engagement reception portion 32b is only required to be a notch shape and not particularly limited; however, a shape narrowing in the depth direction such as a horizontal V-shape is preferred, and particularly a curved concave shape such as a horizontal U-shape or a semicircular shape is preferred in light of engageability with the engaging shaft portion 36.
Note that a distance between adjacent engaging shaft portions 36 is preferably slightly greater than the shortest distance between the engagement reception portions 32b of the electrical contact 32, to facilitate attachment of the electrical contact 32 to the engaging shaft portions 36. In addition, the width of the engagement reception portions 32b is preferably substantially the same as the width of the engaging shaft portion 36, to inhibit up-down movement of the electrical contact 32 upon attachment.
The hook piece portion 32c extends from the lower end portion of the electrical contact 32 to a back face side and is in a hook shape with a fore end portion being bent upward as shown in
The electrical contact 32 is provided with a hole portion 32d in the vicinity of the center as shown in
Furthermore, the electrical contact 32 is provided with a positioning piece 32e extending in the vicinity of the middle of the lower end portion to the back face side as shown in
Detailed description of a method of attaching the electrical contact 32 to the main body portion 31 is provided later.
The upper seal portion 33 and the lower seal portion 34 are configured in a ring shape formed from an elastic material such as rubber, silicon and the like, hermetically seal the space formed by the first holding member 2 and the second holding member 3 as shown in
The upper seal portion 33 is arranged on the inner peripheral side of the main body portion 31, and, in a state in which the substrate W is held, a fore end portion thereof can come into contact with the surface of the substrate W placed on the substrate mount table 22 of the first holding member 2 as shown in
The lower seal portion 34 is arranged on the outer peripheral side of the main body portion 31, and, in a state in which the substrate W is held, a fore end portion thereof can come into contact with the upper face of the body portion 21 of the first holding member 2 as shown in
The upper seal portion 33 and the lower seal portion 34 is fixed in a sandwiched manner between the main body portion 31 and a seal ring holder 37 as shown in
The hanging pin 35 is formed of an electrically conductive metal such as stainless steel, configured in a circular cylindrical shaft shape protruding downward from the lower face of the main body portion 31 as shown in
The locking larger diameter portion 35a is smaller in diameter than the larger diameter hole section 23b of the through hole 23a of the hanging ring 23, and larger in diameter than the smaller diameter hole section 23c, whereby the second holding member 3 can be fixed to the first holding member 2 in such a way that the hanging ring 23 is moved in a state in which the locking larger diameter portion 35a is inserted through the larger diameter hole section 23b as shown in
As for a more detailed configuration of the substrate holder 1, description in paragraphs [0018] to [0114] and the like of the Specification of Japanese Patent Application No. 2018-119875 filed by the present applicants may be referenced.
The electrical contact 32 may be attached to the second holding member 3 as follows, for example.
First, one of left and right end edge portions of the electrical contact 32 is slid into a gap between the head portion 36b of the engaging shaft portion 36 and the inner peripheral face 31a, while the shaft portion 36a is inserted and then advanced deep into the engagement reception portions 32b.
Next, the electrical contact 32 is deflected to be slightly curved, and the other of the left and right end edge portions of the electrical contact 32 is slid into a gap between the head portion 36b of the adjacent engaging shaft portion 36 and the inner peripheral face 31a, while the shaft portion 36a is inserted into the engagement reception portions 32b, and both engagement reception portions 32b are engaged with the engaging shaft portions 36.
An area in the vicinity of the center of the electrical contact 32 is pressed along the inner peripheral face 31a of the second holding member 3, and then the hook piece portions 32c are engaged with the engagement grooves 31d as shown in
And then, the fastening member S such as a screw is inserted into the hole portion 32d and fastened to the second fastening hole 31c, whereby the electrical contact 32 can be fixed to the second holding member 3 as shown in
In order to cause the substrate holder 1 to hold the substrate W, the substrate W is placed on the substrate mount table 22 of the first holding member 2 and then the second holding member 3 is overlaid on the circumference thereof. At this moment, as shown in
By immersing the substrate holder 1 in this state in the plating tank 112 of the substrate plating device 100 shown in
The electrical contact 32 can be removed for replacement by carrying out the steps for attachment in reverse order. For example, the fastening member S, which has been fastened to the hole portion 32d, is loosened and removed, and the electrical contact 32 is pulled in a direction away from the inner peripheral face 32a to remove the hook piece portion 32c from the engagement groove 31d.
Next, while lightly deflecting the electrical contact 32, one of the left and right end edge portions is pulled to disengage the engagement reception portion 32d from the engaging shaft portion 36. And then, the engagement reception portion 32d on the other side is pulled and disengaged from the engaging shaft portion 36, whereby the electrical contact 32 can be removed.
As described above, the present invention enables attachment of the electrical contact 32 to the second holding member 3 through engagement of the engagement reception portion 32b in a notch shape with the engaging shaft portion 36, and enables removal of the electrical contact 32 through disengagement of these members, thus facilitating replacement of the electrical contact 32 and making the replacement operation more efficient.
In addition, the structure of the hook piece portion 32c engageable with the engagement groove 31d permits both the engagement reception portion 32b and the hook piece portion 32c to engage with, and to be less likely to be disengaged from, the second holding member 3. Especially in the case of the second holding member 3 configured in a ring shape, it is easier to follow the arc-like concave portion of the inner peripheral face 31a.
Furthermore, due to the hole portion 32d provided in the vicinity of the center of the electrical contact 32 permitting fastening to the second holding member 3 with the fastening member S such as a screw, reliable fixation is enabled with at least one fastening member, resulting in a smaller number of fixation members than the conventional art while providing the fixation force similar to that of the conventional art.
In the above-described embodiment, the main body portion 31 of the second holding member 3 is formed of an electrically conductive material; however, the present invention is not limited thereto and the main body portion 31 may also be formed of an electrically nonconductive material such as a vinyl chloride resin. In this case, it is preferred that a lower end edge portion of the electrical contact 32 is configured to come into contact with the base plate 25 via an arbitrary elastic member to enable application of an electric current.
In addition, in the above-described embodiment, the substrate holder 1 is configured to be able to hold the round substrate W; however, the present invention is not limited thereto and the substrate holder 1 may also be configured to be able to hold a polygonal substrate such as a rectangular substrate.
For example,
The front plate 11 is provided with an electrical contact 14 on the inner peripheral side as shown in
Also with the substrate holder 10 of such a mode, the above-described attachment structure with the shaft-like engaging shaft portion 36 and the notch-like engagement reception portion 32b may be employed as an attachment structure for the electrical contact 14.
As for details of the substrate holder 10, for example, description in paragraphs [0034] to [0073] of Japanese Patent Laid-Open No. 2018-40045 may be referenced.
Alternatively, it may also be configured to permit plating on both faces of a substrate.
For example,
The first holding member 16 and the second holding member 17 are provided with respective electrical contacts 19a, 19b on the inner peripheral sides as shown in
Also with the substrate holder 15 of such a mode, the above-described attachment structure with the shaft-like engaging shaft portion 36 and the notch-like engagement reception portion 32b may be employed as an attachment structure for the electrical contacts 19a, 19b.
As for details of the substrate holder 15, for example, description in paragraphs [0025] to [0158] of Japanese Patent Laid-Open No. 2019-7075 may be referenced.
In the substrate holder shown in
Number | Date | Country | Kind |
---|---|---|---|
2019-164407 | Sep 2019 | JP | national |
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/JP2020/026552 | 7/7/2020 | WO |