JPH06116760A - Device for simultaneous etching on both sides - Google Patents

Abstract

PURPOSE:To uniformly etch a material to be etched from its inside to its outer peripheral part. CONSTITUTION:An annular member 70 consists of an annular and flat plate and is formed of carbon consisting of the same blank material as the carbon film of the surface of a disk D. The annular member 70 is formed in inside diameter to nearly the same shape as the outside shape of the disk D. The annular member 70 is formed with holes at 3 points and these holes are inserted into threaded parts formed in the upper part of the supporting parts of studs and are screwed and fixed by means of bolts. The annular member 70 is disposed on the horizontal plane of nearly the same height as the bottom end face of a rod 55. The annular member 70 and the disk D exist at the height on the same horizontal plane when the disk D is held between a high-frequency electrode 62 and a substrate holding part 55a. The disk D and the annular member 70 are disposed concentrically in a contact state when the disk D is held between the high-frequency electrode 62 and the substrate holding part 55a.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a double-sided simultaneous etching apparatus for etching the surface of a substrate such as a hard disk.

[0002]

2. Description of the Related Art FIG. 5 shows a conventional substrate holder, but the substrate holder made of a plate-shaped member is generally 3
0, on which a large number of substrate holding portions 31 are formed. As shown in FIG. 5, the details of the substrate holding portion 31 are formed with a substantially circular opening 32 , and an arcuate groove 33 is formed in a lower region of the opening 32 within an angle range shown by a dotted line.
Are formed. A doughnut-shaped substrate D, which is etched on both sides of a carbon film formed on the front and the back like a hard disk, is held on this. Figure 6
Shows that the substrate D is held in the groove 33, and the substrate holder 30 holding the substrate D is carried into the etching chamber B from the preparation chamber A by the drive mechanism 37 as shown in FIG. In the etching chamber B , as shown in FIG. 8, the substrate holder 30 and the ground electrodes 39, 39 are arranged so as to face each other, and the four-cornered corners of the ground electrodes 39, 39 are indicated by the alternate long and short dash line in FIG. There is an earth electrode 39 in the foreground, which is indicated by a chain line), but an opening 39a larger than the diameter of the high frequency electrode 38 is formed, and the high frequency electrode 38 penetrates through the opening 39a to face the substrate holder 30. And is provided in a non-contact state. With this structure,
When the etching chamber B has a predetermined etching atmosphere, the high-frequency electrode 38 moves toward the substrate holder 30 side in the axial direction (dashed line) to contact the surface of the substrate holder 30 which is a conductor, and a high-frequency potential is applied thereto. A high-frequency potential is applied to the substrate D via the substrate holder 30, and the substrate D is etched.

In such a conventional double-sided simultaneous etching apparatus, a plurality of substrates are held in a substrate holder and a high-frequency potential is applied to the substrates through the substrate holder without directly applying the high-frequency potential to the substrates. At the same time, both sides of the substrate were etched. This is because there is a special shape part called “Chamfer” on the outer circumference of the substrate, and it is not possible to have a structure that uniformly holds the outer peripheral surface. Put. Therefore, the contact between the groove of the substrate holder and each substrate or the degree of contact is not uniform, and the high-frequency potential is not evenly transmitted from the substrate holder to each substrate. Further, since the high frequency potential is applied from a limited portion of the outer peripheral portion of the substrate, there is a problem that the potential distribution of the substrate cannot be made concentric.

As described above, the present applicant has developed the following double-sided simultaneous etching device in order to solve the problem in view of the double-sided simultaneous etching device.

FIG. 9 shows a double-sided simultaneous etching apparatus 1 capable of simultaneously etching both front and back surfaces of a substrate.
In the double-sided simultaneous etching apparatus 1, a cylindrical rod 10 vertically penetrates a bottom wall portion 6 of a vacuum chamber 3 and is hermetically arranged. The rod 10 is composed of a hollow cylindrical high frequency electrode 14 electrically isolated from the vacuum chamber 3, and an earth shield 10 'surrounding the high frequency electrode 14, and the upper end of the high frequency electrode 14 is closer to the upper end of the earth shield 10'. It projects slightly upward. Although not shown, cooling water can flow into the internal space 14a of the high-frequency electrode 14 as needed. Further, as shown in the drawing, a substrate D (for example, a hard disk) to be etched is placed on the upper end of the high frequency electrode 14.

The rod 10 consisting of the high frequency electrode 14 and the earth shield 10 'can be vertically moved in the vertical direction as shown by an arrow a, and the high frequency electrode 14 is connected to a high frequency power source 19 so that a high frequency potential can be applied. The ground shield 10 'is connected to the ground. In addition, above the high-frequency electrode 14, a cylindrical rod 9 having a substrate holding portion 9a formed therein is provided opposite to the upper end surface of the insulator 9b.
It is fixed to the upper lid 4 via the, and the periphery of the rod is surrounded by the earth shield 9 except for the tip portion of the substrate holding portion 9a. Although the rod 10 is shown in the lower position in the drawing, when the rod 10 moves upward, the substrate D
Is sandwiched between the high frequency electrode 14 of the rod 10 and the substrate holding portion 9a of the rod 9.

A pair of flat-plate ground electrodes 11 and 12 are provided in the vacuum chamber 3, and both have a donut-shaped flat plate shape like the substrate D. The ground electrode 11 arranged parallel to the etching surface of the substrate D and arranged on the upper side is penetrated by the rod 9 through the opening formed therein, and the lower ground electrode 12 is formed on this. The opening is provided so as to penetrate the rod 10.

Further, the double-sided simultaneous etching apparatus 1 is provided with a gas introduction port 8 in the wall portion 5 for making the inside of the etching chamber C a predetermined etchant gas atmosphere, and is connected to the etching apparatus 1 via a partition valve 13. In the carrier device 2,
A transport mechanism 16 for loading and transporting the substrate D is provided so that the substrate D is placed on the high frequency electrode 14. Further, an exhaust port 7 is provided in the bottom wall portion 6 of the vacuum chamber 3, and an exhaust pump 18 is connected via a partition valve 15.

In the double-sided simultaneous etching apparatus having such a structure, the etching gas is introduced into the substrate D from the gas introduction port 8, and the etching chamber C is evacuated to a predetermined pressure by the vacuum pump 18 via the valve 15. When the rod 10 is transferred to just above the high-frequency electrode 14, the rod 10 is moved upward by a driving means (not shown), and when the substrate D comes into contact with the substrate holding portion 9a at the lower end portion of the rod 9, the rod 10 moves to its position. To stand still. As a result, the substrate D is sandwiched between the high frequency electrode 14 and the substrate holding portion 9a, and when the etching chamber C is brought to a predetermined atmosphere and pressure, a high frequency power source 19 applies a high frequency potential to the high frequency electrode 14 to cause the substrate Etching is performed on the etching treated surface of D.

[0010]

In the conventional double-sided etching apparatus, the outer peripheral portion of the substrate has a remarkably higher etching rate than the central portion of the substrate, and the uniformity of the etching distribution in the substrate cannot be maintained. . This is because the material to be etched is missing at the outer peripheral edge of the substrate, so that positive etching with an etchant gas proceeds at the outer peripheral portion,
This is because the etching rate in the outer peripheral portion is significantly higher than that in the central portion of the substrate, and the etching distribution in the substrate is deteriorated.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a double-sided simultaneous etching apparatus capable of obtaining uniform etching characteristics on the surface of a substrate regardless of the central portion and the outer peripheral portion of the substrate.

[0012]

The above object is to dispose a high-frequency electrode for applying a high-frequency potential to a disk-shaped material to be etched in a vacuum chamber, and a high-frequency electrode arranged in parallel with an etching-treated surface of the material to be etched. In the double-sided simultaneous etching apparatus provided with the grounded electrode, a flat plate having the same material as at least the surface layer of the material to be etched and having a circular opening slightly larger than the diameter of the material to be etched is provided. This is achieved by a double-sided simultaneous etching apparatus, in which an etching material is concentrically arranged in the opening of the flat plate.

Further, the above object is to provide a high-frequency electrode for applying a high-frequency potential to a disk-shaped material to be etched in a vacuum chamber, and a ground electrode arranged in parallel with an etching treated surface of the material to be etched. In the double-sided simultaneous etching apparatus, the flat plate having the same material as at least the surface layer of the material to be etched and a circular opening having the same diameter as the material to be etched is provided, and the material to be etched is opened in the flat plate. It is achieved by a double-sided simultaneous etching apparatus, which is characterized by being inscribed in.

[0014]

Since the flat plate made of the same material as at least the surface layer of the material to be etched and having the circular opening slightly larger than the diameter of the material to be etched is provided close to the outer peripheral portion of the material to be etched, Or, since at least the surface material of the material to be etched is provided with a flat plate in which a circular opening having the same diameter as the material to be etched is formed, and the material to be etched is inscribed in the opening of the flat plate,
It is possible to suppress the progress of positive etching in the outer peripheral portion of the material to be etched.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A double-sided simultaneous etching apparatus in embodiments of the present invention will be described below with reference to the drawings. In this embodiment, the material to be etched will be described using the substrate D which is a hard disk as in the conventional example.

FIG. 1 shows an etching apparatus 50 according to the present invention.
The etching apparatus 50 has a bottom wall 53 of a vacuum chamber 51, and a cylindrical rod 56 penetrating the bottom wall 53. The rod 56 is attached to the bottom wall 53 so as to be vertically slidable and airtight as shown by an arrow b. The rod 56 is composed of a hollow cylindrical high-frequency electrode 62 electrically isolated from the vacuum chamber 51, and an earth shield 56 'surrounding the high-frequency electrode 62. The upper end of the high-frequency electrode 62 is the upper end of the earth shield 56'. It projects slightly above the part. Internal space 62 of high frequency electrode 62
Although not shown in a, cooling water can be flowed as necessary. The figure shows that the substrate D is already fixed on the high-frequency electrode 62. As shown in FIG. 2, the substrate D has an annular shape such as a hard disk in which an opening h is formed, its surface is covered with a carbon coating, and both front and back surfaces are etched.

As shown in FIG. 1, a cylindrical rod 55 is provided on the upper surface of the high-frequency electrode 62, that is, on the mounting surface of the substrate D so as to face it. The rod 55 is composed of an insulator 55b provided with a substrate holding portion 55a at its tip and an earth shield 55 'surrounding the insulator 55b except the tip of the substrate holding portion 55a. Through the opened circular opening, the upper lid 54 of the vacuum chamber 51.
The opening of the ground electrode 57 is formed so as to leave a gap that does not contact the outer peripheral surface of the rod 55. As shown in FIG. 1, the ground electrode 57 is arranged so as to be parallel to the surface of the substrate D when the substrate D is sandwiched between the high frequency electrode 62 and the substrate holding portion 55a. Further, a flat plate-shaped ground electrode 58 is provided below the ground electrode 57 so as to face it, and similarly to the ground electrode 57, when the rod 56 penetrates the opening formed therein, the rod 56 is also provided. The opening is formed so as to open a gap that does not come into contact with the outer peripheral surface of the substrate, and is arranged so as to be parallel to the surface of the substrate D when the substrate D is sandwiched between the high frequency electrode 62 and the substrate holding portion 55a. And a support member 58 that is a conductor
It is attached to the bottom wall portion 53 via a and 58a.

As shown in FIG. 1, a cylindrical stud 61, which is a conductor, is vertically fixed to the bottom wall portion 53 of the vacuum chamber 51. The stud 61 has a high frequency as shown in FIG. The electrodes 62 are arranged at three places at intervals of 120 degrees with respect to the center point of the electrode 62. Stud 61 is ground electrode 58
Are arranged so as to penetrate therethrough in a non-contact state, and therefore three openings are formed in the ground electrode 58 to the extent that the studs 61 penetrate therethrough. In addition, a support portion 61 a that supports the etching compensation outer peripheral structure 60 (hereinafter, referred to as an annular member 60) is formed on the upper portion of each stud 61.

As shown in FIG. 2, the annular member 60 is an annular flat plate, and is made of carbon, which is the same material as the carbon coating on the surface of the substrate D.
Further, the inner diameter of the annular member 60 is formed to be slightly larger than the outer shape of the substrate D, and when the annular member 60 and the substrate D are concentrically overlapped with each other, they are in a non-contact state, and the inner periphery of the annular member 60 and the substrate D. The outer circumference of the is extremely close. The annular member 60 is formed with three holes, and these holes are formed in the support portion 6
1a is inserted into the screw portion formed on the upper portion of the support portion 61a.
It is placed on the stepped part of and fixed by screwing. The annular member 60 is arranged on a horizontal plane having substantially the same height as the lower end surface of the rod 55, and the substrate D is the high frequency electrode 62 and the substrate holding portion 55a.
When sandwiched between and, the annular member 60 and the substrate D are positioned on the same horizontal plane. Since the substrate D is correctly placed concentrically with the high frequency electrode 62 by a transporting means (not shown), the substrate D is sandwiched between the high frequency electrode 62 and the substrate holding portion 55a as shown in the figure. At this time, the substrate D and the annular member 60 are arranged with a very small gap s.

The walls 52 to 54 of the vacuum chamber 51 are at ground potential. Although not shown, the vacuum chamber 51
As in the etching apparatus 1 of the conventional example, a gas inlet is provided, an exhaust port is provided in the bottom wall 53 of the vacuum chamber 51, and an exhaust pump is connected via a partition valve.

The structure of the double-sided simultaneous etching apparatus 50 according to the first embodiment of the present invention has been described above. Next, its operation will be described.

In the double-sided simultaneous etching apparatus 50, when the substrate D is transferred onto the high-frequency electrode 62 by a transfer means (not shown), the rod 56 moves upward, so that the substrate D is removed as shown in FIG. Substrate holding part 5 at the lower end of the rod 55
When it comes into contact with 5a, the rod 56 stops at that position. As a result, the substrate D is sandwiched between the high frequency electrode 62 and the substrate holding portion 55a. Next, the etching chamber E in the vacuum chamber 51 is decompressed by an exhaust pump (not shown), and the etching gas is introduced from the gas inlet. When the etching chamber E has a predetermined atmosphere and pressure, a high-frequency potential is supplied to the high-frequency electrode 62 from a high-frequency power source (not shown), the high-frequency potential is applied to the substrate D, and the etching-processed surface of the substrate D is etched.

The annular member 60 is arranged very close to the outer peripheral portion of the substrate D, and the surface to be etched and the carbon member made of the same material reach from the central portion of the front and back surfaces of the substrate D to the outer peripheral portion, Further, the annular member 60 continuously continues on the same horizontal plane. Therefore, there is no loss except for a slight gap between the substrate D and the annular member 60. Therefore, the carbon member of the annular member 60 suppresses the positive etching by the etchant gas at the outer peripheral portion of the substrate D, the etching rate becomes equal from the central portion of the substrate D to the outer peripheral portion, and the etching is made uniform. . In the present embodiment, there is a gap at the boundary between the annular member 60 and the substrate D, but this gap is extremely small and does not affect the deterioration of the etching distribution in the outer peripheral portion of the substrate D.

As described above, according to this embodiment, the etching rate is the same from the central portion of the substrate D to the annular member 60, the etching rate is improved, and the etching is performed uniformly, so that a high quality substrate is produced. be able to. This is particularly effective when the etching distribution in the central portion and the outer peripheral portion of the substrate D must be strict.

Next explained is a double-sided simultaneous etching apparatus according to the second embodiment of the present invention. In this embodiment, only the structure related to the periphery of the annular member will be described, and the same structures as those in the first embodiment will be designated by the same reference numerals.

The annular member 70 shown in FIGS. 3 and 4 is annular and made of a flat plate, and is made of carbon made of the same material as the carbon coating on the surface of the substrate D. Further, the inner diameter of the annular member 70 is formed to be substantially the same as the outer shape of the substrate D, and when the annular member 70 and the substrate D are concentrically overlapped,
The outer circumference of the substrate D is inscribed in the inner circumference of the annular member 70. Three holes are formed in the annular member 70, and these holes are formed in the upper support portion 71a of the stud 71 as shown in FIG.
It is passed through a threaded portion formed on the upper part of the above, and is mounted and screwed and fixed on the stepped portion of the support portion 71a of the stud 71 made of an insulator. The annular member 70 is arranged on a horizontal plane having substantially the same height as the lower end surface of the rod 55, and when the substrate D is sandwiched between the high frequency electrode 62 and the substrate holding portion 55a,
The annular member 70 and the substrate D are located on the same horizontal plane. Since the substrate D is correctly placed concentrically with the high-frequency electrode 62 by a transfer means (not shown), the substrate D
As shown in the drawing, the high frequency electrode 62 and the substrate holder 5
5a, the substrate D and the annular member 70 are sandwiched between them.
Are concentrically inscribed and arranged in contact.

Although the second embodiment of the present invention has been described above, it is clear that this embodiment also has the same effect as that of the first embodiment. Although the annular member 60 is set to the ground potential in the first embodiment, the stud 71 is made to be an insulator in this embodiment, and when the substrate D is not in contact with the annular member 70, the annular member becomes the floating potential and the high frequency wave is generated. When it comes into contact with the substrate D to which an electric potential is applied, the electric potential becomes the same as the electric potential of the substrate D. It does not matter whether the annular member is insulated from the substrate D or has the same potential.

Although the respective embodiments of the present invention have been described above, the present invention is not limited to these, and various modifications can be made based on the technical idea of the present invention.

For example, the substrate D, which is a hard disk, has been described in each of the above embodiments, but the outer peripheral edge of the hard disk has a specially-shaped portion called a chamfer, and this portion can be strongly touched to avoid deformation. For example, if the material to be etched does not have a special shape such as the chamfer on the outer peripheral portion, the material to be etched may be directly fitted to the annular member in advance without providing the support portion by the stud. Further, each embodiment and substrate D
Although the description has been given of the example in which the substrate is placed on the high frequency electrode in the horizontal direction and the etching process is performed, the substrate D may be held in the vertical direction to perform the etching process.

[0030]

As described above, according to the double-sided simultaneous etching apparatus of the present invention, the etching rate is increased and a uniform etching distribution can be obtained from the inside of the material to be etched to the outer peripheral portion. The quality of material can be improved.

[Brief description of drawings]

FIG. 1 is a front view of a double-sided simultaneous etching apparatus according to a first embodiment of the present invention.

FIG. 2 is a plan view around an annular member of the etching apparatus.

FIG. 3 is a front view of the etching apparatus according to the second embodiment.

FIG. 4 is a plan view of the periphery of an annular member of the etching apparatus.

FIG. 5 is a front view of a substrate holder of a conventional double-sided simultaneous etching apparatus.

FIG. 6 is a side view showing a substrate being held by a substrate holding portion of the substrate holder.

FIG. 7 is a front view showing the inside of the etching apparatus.

FIG. 8 is a side view of the same.

FIG. 9 is a front view of an etching apparatus recently developed by the applicant.

[Explanation of symbols]

 50 Double-sided Simultaneous Etching Device 57 Ground Electrode 58 Ground Electrode 60 Annular Member 70 Annular Member 80 Double-Sided Simultaneous Etching Device

Claims (2)

[Claims] 1. A double-sided surface provided with a high-frequency electrode for applying a high-frequency potential to a disk-shaped material to be etched in a vacuum chamber, and a ground electrode arranged parallel to an etching-treated surface of the material to be etched. In the simultaneous etching equipment,
A plate having the same material as at least the surface layer of the material to be etched and having a circular opening slightly larger than the diameter of the material to be etched was provided, and the material to be etched was concentrically arranged in the opening of the plate. A double-sided simultaneous etching device characterized in that 2. Both sides provided with a high-frequency electrode for applying a high-frequency potential to a disk-shaped material to be etched in a vacuum chamber, and a ground electrode arranged in parallel with an etching treated surface of the material to be etched. In the simultaneous etching equipment,
A flat plate having the same material as at least the surface layer of the material to be etched and having a circular opening with the same diameter as the material to be etched is provided, and the material to be etched is inscribed in the opening of the plate. A double-sided simultaneous etching device characterized by.