JP3321283B2 - Etching equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an etching apparatus for simultaneously etching both surfaces of a substrate such as a hard disk.

[0002]

2. Description of the Related Art A conventional etching apparatus is shown in FIGS.
In these figures, two cassette chambers 5 are provided on the side surface forming the side of the hexagonal robot transfer chamber 51.
2, 53 and the etching chambers 54, 55 are radially connected.

A robot 56 is housed in the robot transfer chamber 51. The robot 56 has substrate holders 56a and 56b for receiving substrates at both ends, and rotates around the center of the robot transfer chamber 51 as an axis. ing.
Therefore, the rotation of the robot 56 allows the substrate holders 56a and 56b to be inserted into the cassette chambers 52 and 53 and the etching chambers 54 and 55.

A cassette stage 57 is provided in each of the two cassette chambers 52 and 53 so as to be movable in the vertical direction. A cassette 58 is mounted on the cassette stage 57. A partition valve 59 is provided at the inlet of the cassette chamber 52, and the outlet of the cassette chamber 52,
A partition valve 60 is provided at a connection portion with the robot transfer chamber 51. A partition valve 6 is provided at the entrance of the cassette chamber 53.
1 is provided, and a partition valve 62 is provided at an outlet of the cassette chamber 53, that is, at a connection portion with the robot transfer chamber 51.

Each of the two etching chambers 54 and 55 is provided with a high-frequency electrode and a raising / lowering mechanism 63. The high-frequency electrode and the raising / lowering mechanism 63 push up the substrate inserted from the robot 56 from the bottom to the upper side. 6
4 and the delivery from the substrate holders 56a and 56b are performed simultaneously. On both sides of the high-frequency electrode 64, other electrodes 65a and 65b are arranged at an interval from the high-frequency electrodes 63 and 64. A partition valve 66 is provided at the entrance of the etching chamber 54, and a partition valve 67 is provided at the entrance of the etching chamber 55.

A cassette insertion mechanism 68 and a cassette rotation mechanism 69 are arranged in the vicinity of the entrance of the cassette chamber 52 in this order.
After the cassette rotation mechanism 69 rotates by a predetermined angle, the cassette 58 is delivered in the order of the cassette rotation mechanism 69, the cassette insertion mechanism 68, and the cassette chamber 52. The cassette introduction mechanism 7 is also provided near the entrance of the cassette chamber 53.
0, the cassette rotating mechanism 71 is arranged in this order, and after the cassette rotating mechanism 71 rotates a predetermined angle, the cassette 5 is rotated.
At 8, delivery is performed in the order of the cassette rotation mechanism 71, the cassette introduction mechanism 70, and the cassette chamber 53.

A transfer line 72 is provided between the cassette rotating mechanism 69 and the cassette rotating mechanism 71, a carry-in port 73 is provided near the cassette rotating mechanism 69, and a carry-in port 73 is provided near the cassette rotating mechanism 71. An outlet 74 is provided.

In the figures, 75, 76, 77, 78, 7
9 is a valve, and 80, 81, 82, 83 and 84 are vacuum pumps.

In such a conventional etching apparatus, first, the cassette 58 sent from the carry-in port 73 is received by the cassette rotating mechanism 69, and the cassette rotating mechanism 6
After rotating the cassette 9 by a predetermined angle, the cassette 58 is transferred from the cassette rotating mechanism 69 to the cassette inserting mechanism 68.

Next, the partition valve 59 is opened, and the cassette 5 is opened.
The cassette 8 is inserted into the cassette chamber 52 from the cassette insertion mechanism 68 and placed on the cassette stage 57, the partition valve 59 is closed, and the inside of the cassette chamber 52 is evacuated.

Next, the partition valve 60 is opened, the substrate holder 56a of the robot 56 is inserted into the cassette chamber 52, and the substrate is placed on the substrate holder 56a. Then, the substrate holder 56a is returned to the robot transfer chamber 51. Robot 56
Is rotated, and the partition valve 66 at the entrance of the etching chamber 54 is rotated.
Is opened, and a substrate holder 56a on which a substrate is placed is inserted into the etching chamber 54.

Thereafter, the substrate is pushed up from below by the high-frequency electrode and the elevating mechanism 63, so that the high-frequency electrode 64 is lifted.
And the delivery from the substrate holder 56a are performed simultaneously. Then, after returning the substrate holder 56a into the robot transfer chamber 51, the partition valve 66 is closed, and an etching gas is introduced into the etching chamber 54 to etch both surfaces of the substrate. When etching with a different gas, the conventional gas is exhausted, and then another gas is introduced into the etching chamber 54. When the etching is completed in this way, the partition valve 66 is opened and the robot 56
Is operated to exchange the substrate after the etching process with a new substrate before the etching process, and the substrate after the etching process is returned to the robot transfer chamber 51.

Next, the robot 56 is operated to return the substrate 64 after the etching process to the cassette 58 in the cassette chamber 52. Thereafter, the cassette stage 57 is moved up and down to change the height, and a new substrate is placed in the substrate holder 56.
a, the robot 56 operates so that etching is performed in another etching chamber 55.

Next, when all the substrates after the etching process are returned to the cassette 58, the partition valve 60 is closed, and the inside of the cassette chamber 52 is returned to the atmosphere. Returning to the atmosphere,
The partition valve 59 is opened, and the cassette 58 in the cassette chamber 52 is moved to the cassette rotation mechanism 69 by the cassette insertion mechanism 68. After that, after rotating the cassette rotating mechanism 69,
The cassette 58 is transferred from the cassette rotation mechanism 69 to the transfer transport line 72, and the cassette 58 is transferred to the cassette rotation mechanism 71 on the transfer transport line 72. After the transfer, the cassette rotation mechanism 71 is rotated, and then the cassette 58
Out.

It should be noted that the cassette chamber 52 is followed by the cassette chamber 5
3, the cassette chamber 52 and the cassette chamber 53 are used alternately. When the cassette chamber 53 is used, the transfer port 7 is used without using the transfer line 72.
The cassette 58 is unloaded from the fourth tray.

[0016]

As described above, the conventional etching apparatus has a pentagonal robot transfer chamber 51, cassette chambers 52 and 53, cassette insertion mechanisms 68 and 70, cassette rotation mechanisms 69 and 71, a transfer line. 72, etc., there is a problem that the floor area on which the apparatus is installed becomes large.

Further, in the case of etching with two different gases in one etching chamber, it takes a long time to degas and adjust the gas pressure, and there is a problem that the production efficiency of the apparatus is reduced.

Further, during opening and closing of the partition valve 66 at the entrance of the etching chamber 54 and the partition valve 67 at the entrance of the etching chamber 55, the etching process and the robot operation cannot be performed, so that the time cannot be shortened and the production efficiency of the apparatus can be reduced. There was a problem of lowering.

An object of the present invention is to solve the conventional problem and to provide an etching apparatus capable of reducing the floor area for installing the apparatus and improving the production efficiency.

[0020]

In order to achieve the above object, an etching apparatus according to the present invention is provided with a plurality of vacuum robot chambers arranged at intervals and a plurality of vacuum robot chambers communicating with each other. An etching chamber for simultaneously etching both surfaces of a single substrate, a loading / unloading chamber formed in a part of the vacuum robot chamber, and a plurality of radially arranged arms arranged between the plurality of vacuum robot chambers, A rotatable structure, a rotatable structure which is attached to each end of a plurality of arms of the rotatable structure so as to be able to move up and down, and which when lowered, becomes a top plate of the loading / unloading chamber; A substrate detaching mechanism provided in the structure, a substrate carrying-in means for carrying in the substrate below the substrate detaching mechanism, and a substrate carrying-out means for carrying out the substrate delivered from the substrate detaching mechanism. Those were.

In the loading / unloading chamber, one side of the opening of the upper plate of the vacuum robot chamber is closed by the top plate structure which can move up and down, and the other side of the opening is the vacuum robot. It is formed by closing the chamber with a vertically movable substrate holder and a rod.

The inside of the vacuum robot chamber has a rotating plate having holes at symmetrical positions with respect to the center and a peripheral edge of the rotating plate having a plurality of other holes for holding a substrate. It comprises a substrate holder to be seated and a rod for pushing up the substrate holder while closing a plurality of other holes of the substrate holder.

[0023]

In this invention, after the substrate conveyed by the substrate carrying means is held by the substrate attaching / detaching mechanism, the rotating structure is rotated stepwise and stopped, and the substrate is loaded / unloaded at the stopped position. Transfer to the chamber from the substrate removal mechanism. Thereafter, the substrate is transferred from the loading / unloading chamber to the etching chamber via the vacuum robot chamber, where both surfaces of the substrate are etched. The processed substrate is returned from the etching chamber to the loading / unloading chamber via the vacuum robot chamber. The returned processed substrate is again held by the substrate detaching mechanism, and then the rotating structure is sequentially rotated in a step-like manner, and passed through another loading / unloading chamber and a vacuum robot chamber to the next etching chamber. Further etching is performed. Then, the substrate on which all the etching processes have been completed is held by the substrate attaching / detaching mechanism, passed to the substrate carrying out unit from the substrate attaching / detaching mechanism, and carried out by the substrate carrying out unit.

[0024]

Embodiments of the present invention will be described below with reference to the drawings. Embodiments of the etching apparatus of the present invention are shown in FIGS. 1, 2, 3, 4, and 5. FIG.
In these figures, the two vacuum robot chambers 1, 2 are arranged at an interval, and the two vacuum robot chambers 1, 2
Between the two, a cross-shaped rotating structure 3 having a plurality of arms 3a, 3b, 3c, 3d radially is arranged. A rotating shaft 4 is attached to the center of the rotating structure 3. The rotating shaft 4 rotates in a step-like manner so that the rotating structure 3 also rotates in a step-like manner. Cylinders 5a, 5b, 5c, and 5d are mounted on the upper ends of the arms 3a, 3b, 3c, and 3d of the rotating structure 3, respectively. Each cylinder 5a, 5b, 5c,
The 5d piston rod 6 has arms 3a, 3b, 3c,
It extends downward through the tip of 3d, and the top plate structures 7a, 7b, 7c, 7d are attached to the tip.
Two cylinders 8 are attached to the upper part of the top plate structure 7a at positions where the cylinders 8 are divided right and left around the piston rod 6. Two cylinders 8 are attached to the other top plate structures 7b, 7c, and 7d in the same manner as in the case of the top plate structure 7a. Around the piston rod 10 of the cylinder 8, a claw 11 having spring elasticity is attached to a lower portion of the top plate structure 7 a so as to surround the piston rod 10.
When 0 goes up and down, the substrate 12 is detached by expanding or narrowing the claws 11. Therefore, each substrate attaching / detaching mechanism 13 includes the cylinder 8, the piston rod 10, and the claw 11.

The substrate carrying means 14 is a rod-shaped guide rail 1
5 and a substrate holder 16 that slides along the substrate holder 5. When the substrate holder 16 slides, the substrate holder 1
The two unprocessed substrates 12 on 6 are carried in below the two substrate attaching / detaching mechanisms 13 of the top plate structure 7a.

On the other hand, the substrate carrying-out means 17 also comprises a rod-shaped guide rail 18 and a substrate holder 19 sliding along the guide rail. When the substrate holder 19 slides, the two substrates of the top plate structure 7a are moved. Substrate holder 1 from attachment / detachment mechanism 13
The two processed substrates 12 transferred on 9 are unloaded.

As shown in FIG. 2, the inside of the box-shaped vacuum robot chamber 1 has a rotating plate 2 that rotates with a rotating shaft 20.
1 is housed. The rotary plate 21 is provided with holes 22 at symmetrical positions with respect to the center.
3 is seated on the periphery of each hole 22 by the action of the spring 24. Two holes 25 are provided in the substrate holder 23 at an interval.

A rod 26 that moves up and down is provided behind the substrate holder 23 of the rotating plate 21. When the rod 26 moves upward, the upper end of the rod 26
3, the substrate holder 23 seated on the periphery of the hole 22 is pushed up, and the substrate holder is placed on the periphery of the opening 1b of the upper plate 1a of the box-shaped vacuum robot chamber 1. 23 is seated from below, and the substrate holder 23 is
And the upper end of a rod 26 for closing the two holes 25 of the substrate holder 23, to close the opening 1b of the upper plate 1a of the vacuum robot chamber 1 from below.

On the other hand, a top plate structure 7b is disposed above the opening 1b of the upper plate 1a of the vacuum robot chamber 1, and a piston rod 6 is driven by driving a cylinder 5b attached to the arm 3b of the rotary structure 3. Moves downward, the top plate structure 7b is seated from above on the periphery of the opening 1b of the upper plate 1a of the box-shaped vacuum robot chamber 1, and the opening 1b of the upper plate 1a
Is closed from above. A vacuum exhaust port 27 is provided in the opening 1b of the upper plate 1a of the vacuum robot chamber 1.

Therefore, the upper plate 1a of the vacuum robot chamber 1
, Top plate structure 7b, substrate holder 23 and rod 2
The opening 1b of the upper plate 1a surrounded by the upper end of the container 6 serves as a loading / unloading chamber 28.

The vacuum robot chamber 1 and the etching chamber 30 communicate with each other via the opening 1c of the upper plate 1a of the vacuum robot chamber 1 above the substrate holder 23 on the opposite side of the cross-shaped rotary structure 3. .

The rotating plate 21 is provided in the loading / unloading chamber 28.
When the two lower rod-shaped lower electrode main bodies 31 which can freely move up and down into the two holes 25 of the substrate holder 23 move upward at a position rotated by 180 °, they are seated on the peripheral edges of the two holes 25. The substrate 12 is pushed up into the etching chamber 30. A cooling water passage 31 a is provided in the lower electrode main body 31.

The substrate 12 pushed up into the etching chamber 30 is moved into the etching chamber 3 within the etching chamber 30.
An insulating rod 33 is provided at the lower part of the top plate 32 which is grounded.
Between the upper electrode main body 34 attached via the lower electrode main body 31 and the upper electrode main body 31 moved upward.

Around the substrate 12 pushed into the etching chamber 30, a plate 35 substantially flush with the substrate 12 is provided.
Are mounted on the wall of the etching chamber 30 which is horizontally grounded, and controls the etching shape around the outer periphery of the substrate 12.

The hollow lower ground rod 36 which is grounded to move up and down together with the lower electrode body 31, around the lower electrode body 31 surrounds with a gap S _1, the upper portion of the lower ground rod 36 a ring-shaped A disk 37 is mounted parallel to the substrate 12.

The upper earth rod 38 attached to the lower part of the top plate 32 surrounds the space between the insulating rod 33 and a part of the upper electrode body 34 with a gap S ₂ .

In FIGS. 2, 4 and 5, 39, 4
Numeral 0 denotes a plate material grounded and mounted in parallel with the substrate 12, 41 and 42 denote the plate materials 39 and 40 in the etching chamber 30.
Reference numeral 43 denotes a partition plate for partitioning the inside of the etching chamber 30 into two.

1 and 2, 44, 45,
46 is a valve, and 47, 48 and 49 are vacuum pumps.

Next, the operation of such an embodiment will be described. First, the substrate holder 16 of the substrate carrying-in means 14 is slid along the guide rail 15, and the two untreated substrates 12 are carried in below the two substrate attaching / detaching mechanisms 13 of the top plate structure 7a.

Second, the two unprocessed substrates 12 are grasped by the two substrate attaching / detaching mechanisms 13 of the top plate structure 7a.
The cross-shaped rotating structure 3 is rotated rightward by 90 ° in a step-like manner and stopped. Due to this clockwise rotation, the positions of the four arms 3a, 3b, 3c, 3d of the rotating structure 3 are also 90 degrees.
° only changed. Therefore, the two unprocessed substrates 1 previously grasped by the two substrate attaching / detaching mechanisms 13 of the top plate structure 7a
2 is located above the vacuum robot chamber 1 on the left side of FIG. Although FIG. 2 shows the arm 3b, the arm 3b and the arm 3a are the same, and the following description will be given based on FIG. 2 without changing the arm 3b to the arm 3a.

Third, the cylinder 5b attached to the arm 3b is driven to move the piston rod 6 downward. At the same time, the top plate structure 7b is moved downward, and the top plate structure 7b is seated on the periphery of the opening 1b of the upper plate 1a of the box-shaped vacuum robot chamber 1, and the opening 1b of the upper plate 1a is closed. Close from above. In this way,
An opening 1b of the upper plate 1a surrounded by the upper plate 1a of the vacuum robot chamber 1, the top plate structure 7b, and the upper ends of the substrate holder 23 and the rod 26 is formed in the loading / unloading chamber 28. After that, the two substrate attaching / detaching mechanisms 13 of the top plate structure 7b
Is operated to place the substrate 12 on the substrate holder 23 in the vacuum robot chamber 1. When the charging / unloading chamber 28 is formed, the charging / unloading chamber 28 is
Is evacuated.

Fourth, when the rod 26 is moved downward, the substrate holder 23 on which the unprocessed substrate 12 is placed is moved by the action of the spring 24 so that the rotating plate 21 in the vacuum robot chamber 1 is moved.
At the periphery of the hole 22 on the side of the loading / unloading chamber 28.

Fifth, when the rotating plate 21 in the box-shaped vacuum robot chamber 1 is rotated by 180 °, the loading / unloading chamber 2 is rotated.
The substrate holder 23 on which the unprocessed substrate 12 is placed, which is seated on the periphery of the hole 22 on the side of the 8, moves toward the etching chamber 30, and conversely, sits on the periphery of the hole 22 on the side of the etching chamber 30, Substrate holder 23 on which processed substrate 12 is placed
Moves to the loading / unloading chamber 28 side.

Sixth, when the two vertically movable lower electrode main bodies 31 for loosely fitting the two holes 25 of the substrate holder 23 in the etching chamber 30 are moved upward, the peripheral portions of the two holes 25 are moved. The substrate 12 seated on the substrate is pushed up into the etching chamber 30, and the substrate 12 is placed in the etching chamber 30 through an insulating rod 33 below the top plate 32 of the etching chamber 30 grounded via an insulating rod 33. And the lower electrode main body 31 moved upward. Then, both surfaces of the substrate 12 are etched in the etching chamber 30.

Seventh, when the two rod-shaped lower electrode bodies 31 are moved downward after the etching process, the processed substrate 12 is also moved downward, and is seated on the periphery of the two holes 25 of the substrate holder 23. I do.

Eighth, the processed substrate 12 can be rotated 180 degrees as described in the fifth section.
When rotated, it moves to the loading / unloading chamber 28 side.

Ninth, when the substrate holder 23 on which the processed substrate 12 moved to the loading / unloading chamber 28 is placed is pushed upward by the rod 26, the box-shaped vacuum robot chamber 1
The substrate holder 23 is seated from below on the periphery of the opening 1b of the upper plate 1a, and the substrate holder 23 and the substrate holder 23
With the upper end of the rod 26 closing the two holes 25, the opening 1b of the upper plate 1a of the vacuum robot chamber 1 is closed from below.

Tenth, by operating the two substrate attaching / detaching mechanisms 13 of the top plate structure 7b, the processed substrate 12 on the substrate holder 23 is gripped by the substrate attaching / detaching mechanism 13, and then the charging / unloading chamber 28 is enlarged. After returning to atmospheric pressure, cylinder 5b
To move the piston rod 6 upward to return the top plate structure 7b to a predetermined position.

Eleventh, when the cross-shaped rotating structure 3 is rotated in a stepwise manner by 90 ° to the right and stopped, the positions of the four arms 3a, 3b, 3c, 3d of the rotating structure 3 are also 90 °. Only changed.

Twelfth, when the cross-shaped rotating structure 3 is further rotated clockwise by 90 ° in a stepwise manner and stopped, the four arms 3a, 3b, 3c, 3
The position of d is also changed by 90 °. For this reason, the two processed substrates 12 previously gripped by the two substrate attaching / detaching mechanisms 13 of the top plate structure 7a are combined with the vacuum robot chamber 1 on the right side of FIG.
Will be located above.

Thirteenth, two processed substrates 12
Is etched by another gas in an etching chamber 30 communicating with the vacuum robot chamber 2 on the right side of FIG.
It is returned to the position of a.

Fourteenth, the cross-shaped rotating structure 3 is rotated clockwise by 90 ° in a stepwise manner to return the two processed substrates 12 to the position of the arm 3a.

Fifteenth, the two processed substrates 12 that have returned to the position of the arm 3 a are removed from the substrate attaching / detaching mechanism 13 and transferred to the substrate holder 19. Thereafter, the substrate holder 19 of the substrate unloading means 17 is slid along the guide rail 18 to unload the two processed substrates 12.

In the above embodiment, two substrates are processed, but the number of substrates need not be limited to this. Therefore, the number of holes in the substrate holder may be changed according to the number of substrates. Further, a single etching chamber and a plurality of etching chambers communicating with the vacuum robot chamber may be provided.

[0055]

According to the present invention, the substrate held by the substrate attaching / detaching mechanism is rotated and conveyed by rotating the rotary structure in a step-like manner as described above, and the substrate is transferred to the loading / unloading chamber. Later, via the vacuum robot chamber, the substrate is transferred to the etching chamber, where both sides of the substrate are etched, and the processed substrate is rotated and conveyed, and both sides are etched in another etching chamber. In addition, the floor area for installing the apparatus can be reduced, and the production efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view taken along line CC of FIG. 1;

FIG. 4 is a sectional view taken along line BB of FIG. 1;

FIG. 5 is a sectional view taken along line DD of FIG. 2;

FIG. 6 is an explanatory view showing a conventional etching apparatus.

FIG. 7 is a sectional view of a conventional etching apparatus.

[Explanation of symbols]

1 Vacuum robot chamber 1a Vacuum robot chamber upper plate 1b Vacuum robot chamber upper plate opening (loading / unloading chamber side) 1c ····· Opening of upper plate of vacuum robot chamber (etching chamber side) 2 ···· Vacuum robot chamber 3a, 3b, 3c, 3d ··· Arm 4 ···・ Rotating shaft 5a, 5b, 5c, 5d ・ ・ ・ ・ ・ ・ Cylinder 6 ・ ・ ・ ・ ・ ・ Piston rod 7a, 7b, 7c, 7d ・ ・ ・ ・ ・ ・ Top plate structure 8 ・ ・ ・ ・ ・ ・··· Cylinder 10 ······ Piston rod 11 ·························································· Substrate carrying-in means 15 Guide rail 16 Substrate holder 17 Substrate carrying-out means 1 8 Guide rail 19 Board holder 20 Rotating shaft 21 Rotating plate 22 Hole 23 ········ Substrate holder 24 ······ Spring 25 ····· Hole 26 ····· Rod 27 ····· Vacuum exhaust port 28 ··· ····· Charging / unloading chamber 30 ······· Etching chamber 31 ······· Lower electrode main body 31a ······· Cooling water channel 32 ········· Top plate 33 ······· Insulating rod 34 ·················································· Lower earth rod 37 ················· Disc 38 ・ ・ ・ ・ ・ ・ ・ Top earth rod

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-61-159572 (JP, A) JP-A-58-113378 (JP, A) JP-A-62-142791 (JP, A) JP-A-3-3 147321 (JP, A) JP-A-61-190944 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C23F 4/00 G11B 5/84 H05K 3/06

Claims (3)

(57) [Claims] 1. A plurality of vacuum robot chambers arranged at intervals, an etching chamber communicated with each of the plurality of vacuum robot chambers, and simultaneously etching both surfaces of at least one or more substrates; A charging / discharging chamber formed in a part of the vacuum robot chamber, a rotating structure having a plurality of arms radiating and rotating in a step shape, and a plurality of arms of the rotating structure. It is attached to each tip so that it can move up and down, and when it descends,
A top plate structure serving as a top plate of the loading / unloading chamber, a substrate attaching / detaching mechanism provided in the top plate structure, substrate carrying means for carrying a substrate below the substrate attaching / detaching mechanism, and the substrate attaching / detaching mechanism An etching apparatus comprising: a substrate unloading unit that unloads the transferred substrate. 2. The loading / unloading chamber, wherein one side of an opening of an upper plate of a vacuum robot chamber is closed by the top plate structure which can move up and down, and the other side of the opening is the vacuum robot. 2. The etching apparatus according to claim 1, wherein the etching apparatus is formed by closing the chamber with a vertically movable substrate holder and a rod. 3. The inside of the vacuum robot chamber has a rotating plate having holes at left and right symmetrical positions with respect to a center, and a plurality of other holes for holding a substrate. 2. The etching apparatus according to claim 1, further comprising a substrate holder to be seated, and a rod for pushing up the substrate plate holder while closing a plurality of other holes of the substrate holder.