JPH0790596A - Surface treating device and surface treatment - Google Patents

Abstract

PURPOSE:To prevent the contact during treatment of adjacent substrates with each other by fitting a spindle provided with annular grooves and a weight bar provided with the similar annular grooves to the ends in the inner peripheral parts of plural doughnut-shaped substrates. CONSTITUTION:The spindle 15 is inserted into the respective hollow parts of the plural doughnut-shaped substrates 7 and the ends on the upper side of the inner peripheral parts of the doughnut-shaped substrates 7 are fitted into the respective annular grooves 15V of the spindle 15 to hang down the doughnut- shaped substrates 7. The weight bar 16 is inserted into the spacings between the respective hollow parts of plural sheets of the doughnut-shaped substrates 7 and the spindle 15 and the inside of the respective annular grooves 16V of the weight bar 16 are fitted to the ends on the lower side of the inner peripheral parts of the respective doughnut-shaped substrates 7 to place the weight bar 16 on the hollow parts of the respective doughnut-shaped substrates 7. Plural sheets of the doughnut-shaped substrates 7 are then immersed into a treating liquid and are subjected to a surface treatment while the spindle 15 is kept rotated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface treatment apparatus and a surface treatment method, and more specifically, it is suitable for simultaneously performing surface treatment such as electroless plating on the surfaces of a plurality of donut-shaped substrates. The present invention relates to a surface treatment device and a surface treatment method.

[0002]

2. Description of the Related Art Conventionally, a technique for subjecting a surface of a substrate to a predetermined treatment has been widely adopted in various fields. As a typical example, a surface of a donut-shaped substrate made of a nonmagnetic material is electroless Manufacturing of a magnetic disk substrate including a step of applying plating can be mentioned.

FIG. 7 is a flow sheet showing an example of a manufacturing process of a non-magnetic disk substrate using the electroless Ni-P plating process (S ₉ ). As a pretreatment step for the electrolytic Ni-P plating step, usually, a plurality of surface treatment steps from a degreasing step (S ₁ ) to an activating step (S ₇ ) are provided.

That is, in the degreasing step (S ₁ ), the substrate surface is cleaned to form a hydrophilic surface, in the neutralization step (S ₃ ) a neutralization treatment is performed, and in the sensitizing step (S ₅ ). Tin ions are adsorbed on the surface of the substrate, and in the activating step (S ₇ ), metal particles serving as catalyst nuclei for the electroless plating reaction are deposited on the surface of the substrate by a reduction reaction. Then, for example, strongly acidic stannous chloride is preferably used for sensitizing, and an aqueous solution of a metal salt such as palladium, platinum, gold, or silver is usually used for activating. A water washing step (S ₂ ) and the like are provided between the above steps.

In the manufacturing process of the above-mentioned magnetic-free disk substrate, electroless Ni which facilitates desorption of hydrogen gas generated by the plating reaction from the substrate is particularly mentioned.
-A surface provided with a plurality of ring-shaped grooves fitted to the end portion of the inner peripheral portion of the donut-shaped substrate on the peripheral surface and having a spindle arranged horizontally because of the necessity in the P plating step (S ₉ ). Using the processing equipment, insert a spindle into each hollow part of multiple donut-shaped substrates, and fit the upper end of the inner peripheral part of each donut-shaped substrate into each ring-shaped groove of the spindle to form a donut-shaped substrate. Is adopted, and then a plurality of donut-shaped substrates are immersed in the treatment liquid, and the surface treatment is performed while rotating the spindle (base rotation method).

Regarding the spindle used in the above-mentioned substrate rotating method, an improvement in the material thereof has been proposed.
It is proposed by each publication of 100613 and 63-100164.

[0007]

By the way, in recent years, along with the miniaturization of magnetic disk devices, the size of the magnetic disk substrate has also been reduced, and in particular, the thickness of the substrate has become thinner (thus lighter). . In the surface treatment of such a magnetic disk substrate by the substrate rotation method, the substrate is apt to rock in the treatment liquid, and as a result, the adjacent members of the substrate suspended in each ring-shaped groove of the spindle are the end portions. Contact at
A problem that scratches occur on the surface of the substrate is caused.
However, the surface treatment apparatus that solves such a problem is
It has not been proposed yet.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a substrate rotation type surface treatment apparatus and a surface treatment method for simultaneously surface treating a plurality of donut-shaped substrates. To provide a surface treatment apparatus and a surface treatment method that solve the contact problem during the treatment of adjacent substrates.

[0009]

That is, the first aspect of the present invention
The gist is an apparatus for simultaneously surface-treating a plurality of donut-shaped substrates, which is provided with a plurality of ring-shaped grooves fitted on the ends of the inner peripheral portion of the donut-shaped substrates on the peripheral surface and arranged horizontally. And a weight bar provided on the peripheral surface with a plurality of ring-shaped grooves fitted to the end of the inner peripheral portion of the donut-shaped substrate and having substantially the same pitch as the ring-shaped grooves of the spindle. The doughnut-shaped substrate surface treatment apparatus is mainly composed of the above-described spindle rotation mechanism.

A second aspect of the present invention is a surface treatment method using the above-mentioned apparatus, wherein a spindle is inserted into each hollow portion of a plurality of donut-shaped substrates, and each of the ring-shaped grooves of the spindle is inserted. The donut-shaped substrate is hung by fitting the upper end of the inner peripheral portion of each donut-shaped substrate to, and further, a weight bar is inserted into the gap between each hollow portion of the plurality of donut-shaped substrates and the spindle, Fit the inside of each ring-shaped groove of the weight bar to the lower end of the inner peripheral portion of each donut-shaped substrate, place the weight bar in the hollow part of each donut-shaped substrate, and then place multiple donut-shaped substrates. A doughnut-shaped substrate surface treatment method is characterized by immersing the substrate in a treatment liquid and performing surface treatment while rotating a spindle.

The present invention will be described in detail below. First, an example of the surface treatment apparatus of the present invention will be described. Figure 1
FIG. 3 is an enlarged view of a main part of the surface treatment apparatus of the present invention, which is a side view showing a state where a donut-shaped substrate is set in the surface treatment apparatus, and FIG. FIG. 3 is an end face explanatory view showing a state where a donut-shaped substrate is set in the surface treatment apparatus, and FIG. 3 is an explanatory view showing a positional relationship between a spindle and a weight bar when setting the donut-shaped substrate in the surface treatment apparatus of the present invention. FIG. 4 is an explanatory view showing a preparation state for surface treatment using the surface treatment apparatus of the present invention, and FIG.
An explanatory view showing a setting state of a donut-shaped substrate in a preparation state for surface treatment using the surface treatment apparatus of the present invention,
FIG. 6 is an enlarged explanatory view of the main part shown in FIG.

The surface treatment apparatus of the present invention, as shown in FIGS. 1 and 2, has an end portion (7) of the inner peripheral portion of the donut-shaped substrate (7).
A plurality of ring-shaped grooves (15v) that fit in 1), ...
(15) with a peripheral surface and a horizontal arrangement
And a plurality of ring-shaped grooves (16v) fitted to the end portion (71) of the inner peripheral portion of the donut-shaped substrate and having substantially the same pitch as the ring-shaped groove (15v) of the spindle.
.. is mainly constituted by the weight bar (16) provided on the peripheral surface and the spindle rotating mechanism. In addition,
The rotation mechanism of the spindle will be described later.

The spindle (15) is made of a material inert to the processing liquid, and is usually selected from metals, ceramics, plastics and the like in consideration of the type of the processing liquid. A material obtained by coating a core rod of stainless steel or an austenitic alloy with polypropylene is preferably used. One ring-shaped groove (15) provided on the peripheral surface of the spindle (15)
v) is formed in a direction perpendicular to the axis as a single ring-shaped groove extending over the entire peripheral surface. Then, the ring-shaped groove (15
The shape of v) is not particularly limited, and a concave shape, a V shape, a U shape, or the like can be adopted as appropriate, but a groove having a V-shaped concave bottom is preferably adopted.

The width, depth, etc. of the ring-shaped groove (15v) depend on the size of the donut-shaped substrate (7), and the ring-shaped groove is formed in the end portion (71) of the inner peripheral portion of the donut-shaped substrate (7). (15
v) is appropriately determined so that it can be fitted sufficiently. And
Mutual spacing (pitch) between a plurality of ring-shaped grooves (15v)
And the number thereof is not particularly limited, and the spindle (15)
An appropriate interval can be selected in consideration of the number (processing capacity) of the donut-shaped substrates (7) set in the above.

However, when a magnetic disk substrate is manufactured by using a donut-shaped substrate made of a non-magnetic material as the donut-shaped substrate (7), usually 25 such donut-shaped substrates are set in a cassette. It is housed and traded, and the board interval is usually 0.247 to 0.25.
3 inch range, typically 0.250 inch (6.3
5 mm), it has multiple ring-shaped grooves (1
It is convenient that the mutual spacing (pitch) of 5v) is the same spacing as the above-mentioned substrate spacing.

The weight bar (16) has a spindle (1
Similar to 5), it is composed of a material that is inert to the processing liquid, but especially the material in which the core rod of stainless steel or austenite alloy is coated with Teflon has good slidability with the donut-shaped substrate (7). Therefore, it is preferably used. One ring-shaped groove (1 provided on the peripheral surface of the weight bar (16)
6v) is formed in the direction perpendicular to the axis as a single ring-shaped groove extending over the entire peripheral surface. Then, the ring-shaped groove (1
The shape of 6v) is not particularly limited, and the spindle (15)
The shape similar to the ring-shaped groove (15v) can be appropriately adopted, but the V shape or the U shape is preferably adopted.

The width, depth, etc. of the ring-shaped groove (16v) are appropriately determined according to the same criteria as in the case of the ring-shaped groove (15v). The spacing (pitch) should be substantially the same as the spacing (pitch) between the plurality of ring-shaped grooves (15v) of the spindle (15). When the pitch in the ring-shaped groove (16v) of the weight bar (16) and the pitch in the ring-shaped groove (15v) of the spindle (15) are significantly different, a plurality of donut-shaped substrates (7) are attached to the spindle (15). When set, not only donut-shaped substrates (7) cannot be held vertically, but also adjacent donut-shaped substrates (7)
The ends of the comrades will come into contact.

The spindle (15) and the weight bar (1
6) are both inserted into each hollow part of the donut-shaped substrate (7). Therefore, these outer diameters have a predetermined size in consideration of the work of inserting the doughnut-shaped substrate (7) into each hollow portion. Usually, the outer diameter of the weight bar (16) is made smaller than the outer diameter of the spindle (15). The details of the operation of setting a plurality of donut-shaped substrates (7) on the spindle (15) will be described later, but usually, the donut-shaped substrates (7) are set.
The weight bar (16) is inserted in the gap between the hollow part of the spindle and the spindle (15).

In the present invention, in order to facilitate the above insertion operation of the weight bar (16) without making the outer diameters of the spindle (15) and the weight bar (16) unnecessarily small, it is shown in FIG. As described above, it is preferable to provide a single cutout portion capable of fitting the peripheral surface of one of the spindle (15) and the weight bar (16) in the axial direction with the other peripheral surface.

The notch shown in FIG. 3 is composed of a ring-shaped groove (15r) formed on the spindle (15) side (referring to the left and right ring-shaped grooves of the protrusion (15p)). In order to make the above-mentioned insertion operation of the weight bar (16) easier,
A single protrusion (15p) is formed along the axial direction, and the protrusion (15p) is formed on the circumferential surface of the weight bar (16) in the axial direction.
The ring-shaped groove (16q) that fits in p) is formed.

According to the above embodiment, the spindle (1
The weight bar (16) is placed in the ring-shaped groove (15r) of 5).
By fitting the two together and overlapping them, the operation of inserting the weight bar (16) into the gap between the hollow portion of the donut-shaped substrate (7) and the spindle (15) becomes easy, and furthermore, the spindle (15) By fitting the protrusion (15p) and the ring-shaped groove (16q) of the weight bar (16), it is possible to ensure the above-mentioned superposition of the spindle (15) and the weight bar (16).

The surface treatment apparatus of the present invention is generally capable of successively moving over a plurality of independent processing baths for performing a plurality of target surface treatments, and a donut-shaped substrate is placed in the processing liquid in each processing bath. It is configured so that it can be moved up and down so that it can be immersed. Such an embodiment is, for example, as shown in FIG. 4, a slider (2), a suspension jig (21), a lifting mechanism (2).
2), it can be realized by using the transport rail (3).

The surface treatment apparatus (1) illustrated in FIG. 4 is provided with locking portions (11b) and (11b) which are arranged at both ends and whose upper ends are bent inward. A transfer rail (3) is horizontally and parallel to the processing tank (5) and other processing tanks (not shown) following the processing tank (5) on an appropriate support column arranged in the vicinity of the processing tank (5). It is installed. The slider (2) traveling on the transport rail (3) is provided with an elevating mechanism (22) such as a screw type or a chain type, and an inverted T-shaped suspension jig ( 21) is provided, and the suspension jig can be raised and lowered by an elevating mechanism (22). Reference numeral (23) is a drive motor of the lifting mechanism (22). The state shown in FIG.
The T-shaped part of the suspension jig (21) is engaged between the locking parts (11b) and (11b) of the surface treatment device (1), and the surface treatment device (1) is suspended above the treatment tank (5). It shows the state of being done.

Further, in the surface treatment apparatus of the present invention, the gear train illustrated in FIGS. 5 and 6 can be used for the rotation mechanism of the spindle (15). That is, the illustrated rotation mechanism has locking portions (11b), (11
The horizontal frame (11a) supported by b), and the bearings (12c), (12c) provided on the left and right under the horizontal frame (11a).
And a rotary shaft (12) supported horizontally by these bearings, and a gear (1) fitted in a substantially central portion of the rotary shaft.
2g) and gears (14g) and (1
5g), a motor (13) arranged at the upper end of the horizontal frame (11a), and sprockets (13s) and (1) for transmitting the rotational drive of the motor to the rotary shaft (12).
2S) and a chain (12c).

The gears (14g) and (15g) are placed in the horizontal frame (11a) with the gear (12g) sandwiched therebetween.
Left and right vertical frames (14) provided in the substantially central part of the
It is arranged by an appropriate means between (14). And
A spindle (15) is fitted to the gear (15g), and the rotation of the motor (13) is driven by a sprocket (13s), a chain (12c), and a sprocket (12).
S), rotary shaft (12), gear (12g), (14g),
It is transmitted to the spindle (15) via (15g).
In the illustrated example, a spindle (15) having a plurality of ring-shaped grooves (15v) provided on the left and right peripheral surfaces is used, and a gear (15g) is fitted in the center of the spindle (15), so that the spindle (15) A plurality of donut-shaped substrates (7) can be set on each of the left and right sides of the.

The donut-shaped substrate (7) can be set on the spindle (15) efficiently by using the donut-shaped substrate attaching / detaching device (4) illustrated in FIGS. 5 and 6. The doughnut-shaped substrate attaching / detaching device (4) is an open upper (U-shaped) pedestal (41) and a horizontal space having a predetermined lower space inside the gantry and having a space portion at a substantially central portion. It is composed of a base (42), a cassette moving mechanism (43) arranged on the horizontal base, and an elevating mechanism (44) arranged under the frame (41).

At the left and right ends of the pedestal (41), end support portions (4) for locking the rotating mechanism of the spindle (15).
1e) is provided, and the rotation mechanism described above is locked to the support portion (41e) at a substantially central portion of the bottom of the gantry (41) (position facing the space of the horizontal base (42)). In the rotating mechanism (vertical frame (14), (1
4)) is in contact with the central support portion (41f).

The cassette moving mechanism (43) has a rail (43r) and a traveling roller (4) provided at the bottom thereof.
It is composed of a cassette table (43a) that travels on the rail (43r) by 3s) and an upper open type cassette (6) that is placed on the cassette table. In the illustrated example, two sets of the cassette moving mechanism (43) are arranged on the left and right of the central space of the horizontal base (42), and a plurality of donut-shaped substrates (7) are arranged on the left and right of the spindle (15). ) Can be set. Further, the elevating mechanism (44) can be configured by, for example, a hydraulic jack device.

Next, the surface treatment method of the present invention using the above-mentioned donut-shaped substrate attaching / detaching device (4) will be described. In the surface treatment method of the present invention, the spindle (15) is inserted into each hollow portion of the plurality of donut-shaped substrates (7), and each donut-shaped substrate (in each ring-shaped groove (15v) of the spindle (15) ( 15) the upper end of the inner circumference (7)
1) is fitted and the donut-shaped substrate (15) is hung,
Further, a weight bar (16) is inserted into the gap between each hollow portion of the plurality of donut-shaped substrates (7) and the spindle (15), and the lower end of the inner peripheral portion of each donut-shaped substrate (7) is inserted. (7
1) Each ring-shaped groove (16v) of the weight bar (16)
The weight bar (16) is placed in the hollow portion of each donut-shaped substrate (7) by fitting the inside, and then, the plurality of donut-shaped substrates (7) is immersed in the treatment liquid, and the spindle (15)
Surface treatment is performed while rotating.

The donut-shaped substrate (7) is intended to be a donut-shaped substrate having a hardness that allows it to stand vertically vertically when suspended in the ring-shaped groove (15v) of the spindle (15). As such a donut-shaped substrate, for example,
A magnetic disk base and an optical disk base are typical. These substrates are made of aluminum, ceramics, glass,
It is made of non-magnetic material such as plastics.

First, in the surface treatment method of the present invention,
A cassette (6) accommodating a plurality of donut-shaped substrates (7) is placed on the cassette moving mechanism (43), the elevating mechanism (44) is driven to raise the gantry (41), and the gantry. The rotation mechanism of the spindle (15) is stopped by the end support portion (41e) and the central support portion (41f) of (41), and then the cassette base (43a) of the cassette moving mechanism (43) is placed on the rail (43r). The doughnut-shaped substrates (7) to move the spindle (1
Insert 5).

Then, the elevating mechanism (44) is driven to lower the pedestal (41) to move the spindle (1
The upper end portion (71) of the inner peripheral portion of each donut-shaped substrate (7) is fitted into each ring-shaped groove (15v) of 5) to suspend the donut-shaped substrate (7). Then, the weight bar (16) is inserted into the gap between the hollow portion of the donut-shaped substrate (7) and the spindle (15), and the weight bar (16) is inserted into the lower end (71) of the inner peripheral portion of each donut-shaped substrate (7). The ring-shaped groove (16v) of the weight bar (16) is fitted and the weight bar (16) is placed in the hollow portion of each donut-shaped substrate (7).

When the upper and side open type cassettes are used as the cassette (6), the spindle (15) is inserted into each hollow portion of the plurality of donut-shaped substrates (7) and then the pedestal ( It is also possible to set the weight bar (16) before lowering 41).

Then, the surface treatment apparatus (1) is raised by the elevating mechanism (22) described above, and is moved to the upper side of the target treatment tank by the slider (2), and the elevating mechanism (2) is moved.
2) Dropped by donut-shaped substrates (7)
Is immersed in the treatment liquid, and the surface treatment is performed while rotating the spindle (15).

In the surface treatment apparatus and method of the present invention, the donut-shaped substrate (7) revolves in the ring-shaped groove (15v) of the spindle (15) by the rotation of the spindle (15). Further, the weight bar (16) is provided with an end portion (7) of the inner peripheral portion of the donut-shaped substrate (7).
Revolve while rotating in 1). Then, in the surface treatment performed in such a state, the donut-shaped substrate (7) is
Spindle (15) and weight bar (1) parallel to each other
The donut-shaped substrate (7) does not fall off the spindle (15) because it is retained by the ring-shaped grooves (15v) and (16v) with the adjacent donut-shaped substrate (6). The end of 7) does not touch.

[0036]

EXAMPLES The surface treatment method of the present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples as long as the gist thereof is not exceeded. In addition,
The following example uses the surface treatment apparatus of the present invention equipped with the moving mechanism shown in FIG. 4 and the rotating mechanism of the spindle (15) shown in FIGS. 5 and 6, and according to the flow sheet shown in FIG. It is an example of the surface treatment performed for the manufacture of.

Example 1 The spindle (15) is made of a material in which a stainless steel core rod is coated with polypropylene, and has a single ring-shaped groove (a concave horizontal bottom having a V-shaped groove) over the entire peripheral surface.
Maximum width of ring groove: 1.5 mm, depth of ring groove: 2.
Outer diameter 15.0 with 5 mm, pitch: 6.35 mm)
mm spindle, and the weight bar (16) is made of a material in which a core rod of austenitic alloy is coated with Teflon, and has a single V-shaped ring-shaped groove (ring-shaped groove maximum width over the entire circumferential surface). : 3.0 mm, ring-shaped groove depth: 2.0 mm, pitch: 6.35 mm), and a weight bar having an outer diameter of 6.0 mm was used. Further, the donut-shaped substrate (7) has an outer diameter of 65 mm, an inner diameter of 20 mm, and a thickness of 0.635 mm, and a glass substrate (2.5 inch size) housed as a set of 25 sheets in an upper open cassette. 2 sets were used.

First, two sets of cassettes (6) are respectively placed on the left and right cassette moving mechanisms (43), the elevating mechanism (44) is driven to raise the gantry (41), and then the gantry ( 41) is engaged with the end support portion (41e) and the central support portion (41f) to make the rotation mechanism of the spindle (15) stand still, and then the cassette base (43a) of the cassette moving mechanism (43) is connected to the rail ( 43r), the left and right spindles (15) were inserted into the hollow parts of the doughnut-shaped substrates (7) of each set.

Then, the elevating mechanism (44) is driven to lower the gantry (41) to move the spindle (1
The donut-shaped substrate (7) was suspended by fitting the upper end portion (71) of the inner peripheral portion of each donut-shaped substrate (7) into each ring-shaped groove (15v) of 5). Then, the weight bar (16) is inserted into the gap between the hollow portion of the donut-shaped substrate (7) and the spindle (15), and the weight bar (16) is inserted into the lower end (71) of the inner peripheral portion of each donut-shaped substrate (7). The ring-shaped groove (16v) of the weight bar (16) was fitted and the weight bar (16) was placed in the hollow portion of each donut-shaped substrate (7).

Next, the elevating mechanism (22) raises the surface treatment apparatus (1), the slider (2) moves it to above the alkaline treatment tank in the degreasing step (S ₁ ), and the elevating mechanism (22) lowers it. The doughnut-shaped substrate (7) was immersed in an alkaline aqueous solution, and surface treatment was performed while rotating the spindle (15). The rotation speed of the spindle (15) was controlled at 6 rpm.

Next, the elevating mechanism (22) raises the surface treatment apparatus (1), the slider (2) moves it to above the pure water cleaning tank in the water washing step (S ₂ ), and the elevating mechanism (22) lowers it. Then, the doughnut-shaped substrate (7) was immersed in pure water, and the surface treatment was performed while rotating the spindle (15). The rotation speed of the spindle (15) is 6r
Controlled to pm.

Thereafter, the same operation as described above is repeated, and FIG.
In accordance with the flow sheet shown in FIG. 1, a plurality of surface treatment steps from the neutralization step (S ₃ ) to the electroless Ni-P plating step (S ₉ ) are performed, and the surface of the glass substrate is exposed to a thickness of 0.1.
A Ni-P plated layer having a thickness of 5 μm was formed. The conditions such as liquid composition, temperature, and pH used in each step were known and ordinary conditions. Then, the presence or absence of scratches on the surface of the obtained magnetic disk substrate was investigated. The investigation was performed by visual observation using an illuminating device "MODEL-LSD" manufactured by Olympus Optical Co. No scratch was generated on any of the 50 glass substrates, and the plating yield was 100%.

Example 2 Example 1 was repeated except that a glass substrate (1.8 inch size) having an outer diameter of 48 mm, an inner diameter of 12 mm and a thickness of 0.381 mm was used as the doughnut-shaped substrate (7).
A magnetic disk substrate was obtained in the same manner as in (1) and examined for scratches on its surface. Each of the 50 glass substrates,
No scratch was generated and the plating yield was 100%.

Comparative Example 1 and Comparative Example 2 A magnetic disk substrate was obtained in the same manner as in Example 1 and / or Comparative Example 1 except that the weight bar (16) was not used. The presence or absence of scratches on the surface was investigated. Comparative Example 1 corresponds to Example 1 with 2.5
This is an example using an inch size glass substrate, and Comparative Example 2
Is an example in which a glass substrate having a size of 1.8 inches is used corresponding to Example 2. In each of the comparative examples, all of the 50 glass substrates had scratches, and the plating yield was 0%.

[0045]

According to the present invention described above, there is provided an apparatus and method for simultaneously surface-treating a plurality of donut-shaped substrates, and in particular, a surface which solves the contact problem between adjacent substrates during processing. A treatment apparatus and a surface treatment method are provided, and the industrial value of the present invention is remarkable.

[Brief description of drawings]

FIG. 1 is an enlarged view of a main part of a surface treatment apparatus of the present invention, which is a side view showing a state where a donut-shaped substrate is set in the surface treatment apparatus.

FIG. 2 is an enlarged view of a main part of the surface treatment apparatus of the present invention, which is an end face explanatory view in a state where a donut-shaped substrate is set in the surface treatment apparatus.

FIG. 3 is an explanatory diagram showing a positional relationship between a spindle and a weight bar when setting a donut-shaped substrate in the surface treatment apparatus of the present invention.

FIG. 4 is an explanatory diagram showing a preparation state for surface treatment using the surface treatment apparatus of the present invention.

FIG. 5 is an explanatory diagram showing a setting operation state of a donut-shaped substrate in a preparation state for surface treatment using the surface treatment apparatus of the present invention.

FIG. 6 is an enlarged explanatory view of a main part shown in FIG.

FIG. 7 is a flow sheet showing an example of a manufacturing process of a magneticless disk substrate that employs an electroless Ni—P plating process (S ₉ ).

[Explanation of symbols]

 7: Donut-shaped substrate 71: End of inner peripheral portion of donut-shaped substrate 15: Spindle 15v: Ring-shaped groove 16: Weight bar 16v: Ring-shaped groove

Claims (3)

[Claims] 1. An apparatus for simultaneously surface-treating a plurality of donut-shaped substrates, wherein a plurality of ring-shaped grooves fitted to the end portions of the inner peripheral portion of the donut-shaped substrates are provided on the peripheral surface and horizontal. And a plurality of ring-shaped grooves fitted on the end of the inner peripheral portion of the donut-shaped substrate and having substantially the same pitch as the ring-shaped grooves of the spindle on the peripheral surface. A doughnut-shaped substrate surface treatment apparatus comprising a bar and the above-described spindle rotation mechanism. 2. A surface treatment method using the apparatus according to claim 1, wherein a spindle is inserted into each hollow portion of a plurality of donut-shaped substrates, and each donut-shaped substrate is placed in each ring-shaped groove of the spindle. The donut-shaped substrate is hung by fitting the upper end of the inner periphery of the donut-shaped substrate, and further, a weight bar is inserted in the gap between each hollow portion of the plurality of donut-shaped substrates and the spindle, Fit the inside of each ring-shaped groove of the weight bar to the lower end of the inner peripheral part and place the weight bar in the hollow part of each donut-shaped substrate, and then immerse the donut-shaped substrates in the treatment liquid. A surface treatment method for a donut-shaped substrate, which comprises performing surface treatment while rotating a spindle. 3. The surface treatment method according to claim 2, wherein the doughnut-shaped substrate is a substrate made of a nonmagnetic material, and the surface treatment is electroless plating.