JP2010185105A - Thin-film-forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thin-film-forming apparatus which can prevent an electrical current on a substrate from becoming nonuniform when voltage has been applied to a high-frequency electrode. <P>SOLUTION: The thin-film-forming apparatus 1 includes: a film-forming chamber 3 which is composed of two box-shaped film-forming chamber wall bodies 3A and 3B that are arranged so as to sandwich the substrate 2; the high-frequency electrode 4 which is arranged in one film-forming chamber wall body 3A; and an earth electrode 5 which is arranged in the other film-forming chamber wall body 3B. The one film-forming chamber wall body 3A includes: a block part 7; a chamber part 8 arranged on the side of the substrate 2 with respect to the block part 7; and a frame body 9 arranged on the side of the substrate 2 with respect to the chamber part 8. The chamber part 8 has the high-frequency electrode 4 in its inner part, and the frame body 9 surrounds the outer perimeter of the high-frequency electrode 4. The frame body 9 is connected with the block part 7 by an electroconductive member 13. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a thin film forming apparatus configured to form a thin film used in a thin film solar cell, a semiconductor, or the like on a substrate by generating a plasma discharge between a ground electrode and a high frequency electrode arranged in the film forming chamber. About.

  Thin-film solar cells are thin and lightweight, are low-cost, and can be easily increased in area, and are considered to become the mainstream of future solar cells. A thin film solar cell has various thin films laminated therein, and these thin films are usually formed using a thin film forming apparatus (for example, a CVD apparatus).

Currently, as a thin film forming apparatus, there are a roll-to-roll system or a stepping roll system. Both types have transport means consisting of a plurality of rolls, and the roll-to-roll method is a method in which a thin film is continuously formed on a substrate that moves continuously in each film forming chamber. In this method, a thin film is formed on a substrate that is simultaneously stopped in each film formation chamber, and the film-formed portion is sent to the next film formation chamber.
Among these, the stepping roll type thin film forming apparatus is excellent in that the characteristics of each thin film can be stably obtained because gas diffusion between adjacent film forming chambers can be prevented.

FIG. 3 is a view showing a conventional stepping roll type thin film forming apparatus 1.
As shown in FIG. 3, the thin film forming apparatus 1 includes a film forming chamber 3 including two box-shaped film forming chamber walls 3A and 3B arranged so as to sandwich a substrate 2, and one film forming chamber wall. A high-frequency electrode 4 disposed on 3A and a ground electrode 5 disposed on the other film forming chamber wall 3B are provided.

As shown in FIG. 3, the high-frequency electrode 4 is formed in a hollow shape so as to introduce a reaction gas therein, and is connected to a high-frequency power source 6 for applying a voltage.
Further, the film formation chamber wall 3A in which the high-frequency electrode 4 is disposed includes a block portion 7 having a rectangular frame structure, a chamber portion 8 disposed on the substrate 2 side with respect to the block portion 7, and the chamber portion 8 A high-frequency electrode 4 is provided inside the chamber section 7. The high-frequency electrode 4 is provided with a frame body (frame) 9 disposed on the substrate 2 side. Further, the frame body 9 is disposed so as to surround the outer periphery of the high-frequency electrode 4 and is fixed on the chamber portion 8 with a bolt 10 (see FIG. 4). Here, the bolt 10 is formed in such a length that it can reach the block portion 7, and the current flowing in the frame body 9 is allowed to escape to the block portion 7.
In this thin film forming apparatus 1, a reactive gas is introduced into the film forming chamber 3 through the high-frequency electrode 4, and plasma discharge is performed between the high-frequency electrode 4 and the ground electrode 5 with a voltage applied to the high-frequency electrode 4. As a result, a thin film is formed on the substrate 2.

On the other hand, Patent Document 1 similarly discloses a thin film forming apparatus including a film forming chamber 1 composed of two film forming chamber frames 10a and 10b.
In the thin film forming apparatus of Patent Document 1, the ground electrode 3 is disposed on one film forming chamber frame 10a, and the high frequency electrode 4 connected to a high frequency power source is disposed on the film forming chamber frame 10b. As a result, the thin film forming apparatus of Patent Document 1 forms a thin film on the substrate by generating plasma discharge between the high-frequency electrode 4 and the ground electrode 3.

JP 2008-106304 A

FIG. 4 is a plan view of the film forming chamber wall 3A in the thin film forming apparatus 1 of FIG. 3 as viewed from above (the substrate 2 side).
When a voltage is applied to the high-frequency electrode 4 in the conventional thin film forming apparatus 1, the current flows toward the lower potential on the substrate 2, so that the arrows A, B, C, D, E, F, G, and H As shown, the current flows toward the frame 9 having a low potential. Then, the current flowing toward the frame body 9 flows to the block portion 7 via the bolt 10.

  Here, in the conventional thin film forming apparatus 1, since it is considered that the current flows in the shortest distance with respect to the frame 9 having a low potential, a large amount of current flows particularly in the portions indicated by arrows A, B, E, and F. As described above, when the current is concentrated on the portions of the arrows A, B, E, and F on the substrate 2, the current on the substrate 2 becomes non-uniform, so that the film thickness of the substrate 2 may not be formed uniformly. It was.

  The present invention has been made in view of such a situation, and an object of the present invention is to form a thin film capable of preventing current on a substrate from becoming non-uniform when a voltage is applied to a high-frequency electrode. Is to provide a device.

  In order to solve the above-described problems of the prior art, according to an embodiment of the present invention, a film formation chamber composed of two box-shaped film formation chamber walls arranged so as to sandwich a substrate, and one film formation A high-frequency electrode disposed on the chamber wall and connected to a high-frequency power source; and a ground electrode disposed on the other film-forming chamber wall and disposed so as to face the high-frequency electrode. Thin film formation configured to form a thin film on the substrate by introducing a plasma discharge between the high frequency electrode and the ground electrode with the voltage applied to the high frequency electrode while being introduced into the film forming chamber. In the apparatus, the one film formation chamber wall includes a block, a chamber disposed on the substrate side with respect to the block, and a frame disposed on the substrate with respect to the chamber. The chamber section is Serial high-frequency electrode has inside, the frame body, the surrounds the outer periphery of the high-frequency electrode, the frame body and said block portion is connected with the conductive member.

  According to another embodiment of the present invention, the frame-side end of the conductive member is fixed to the side surface of the frame with screws, and the block-side end of the conductive member is the block portion. It is fixed with screws on the sides.

  According to another embodiment of the present invention, the upper end of the frame member side end portion of the conductive member is formed to extend to the high frequency electrode side, and the extension portion has elasticity. It is formed to be curved.

  As described above, according to the thin film forming apparatus of the present invention, the film forming chamber composed of two box-shaped film forming chamber walls arranged so as to sandwich the substrate, and one film forming chamber wall body are arranged. A high-frequency electrode connected to a high-frequency power source, and a ground electrode disposed on the other film-forming chamber wall and opposite to the high-frequency electrode, and introducing a reaction gas into the film-forming chamber In the thin film forming apparatus configured to form a thin film on the substrate by performing plasma discharge between the high frequency electrode and the ground electrode in a state where a voltage is applied to the high frequency electrode, The film forming chamber wall includes a box-shaped block, a chamber disposed on the block, and a frame disposed on the chamber. The chamber includes the high-frequency electrode. And said The body surrounds the outer periphery of the high-frequency electrode, and the frame body and the block portion are connected by a conductive member. Therefore, when a voltage is applied to the high-frequency electrode, the current flows toward the frame body having a low potential. Current flows through the conductive member to the block portion. Thus, not only the bolts on the frame, etc., but also the conductive member can release the current, so when the current flows from the substrate toward the frame, the current does not concentrate on the part toward the bolts, The current flowing on the substrate can be made uniform. Thereby, the film thickness distribution of the thin film on the substrate can be kept uniform.

  According to the thin film forming apparatus of the present invention, the end of the conductive member on the frame side is fixed to the side surface of the frame with screws, and the end of the conductive member on the block portion side is the block portion. Since the end of the conductive member on the frame body side reliably contacts the frame body, the end of the conductive member on the block side also reliably contacts the block portion. Thereby, the electric current that has flowed toward the frame can be more reliably passed through the conductive member.

  Further, according to the thin film forming apparatus of the present invention, the upper end of the end portion on the frame side of the conductive member is formed to extend to the high-frequency electrode side, and the extending portion has elasticity. When the thin film forming apparatus is used repeatedly, even if the conductive member is stretched due to heat, the contact state between the conductive member and the frame is maintained by the elasticity of the extending portion. As a result, the current flowing toward the frame can be more reliably passed through the conductive member.

It is sectional drawing which showed the thin film forming apparatus which concerns on embodiment of this invention. It is the top view which looked at one film-forming chamber frame of the thin film formation apparatus of FIG. 1 from upper direction. It is sectional drawing which showed the conventional thin film forming apparatus. It is the top view which looked at one film-forming chamber frame of the thin film formation apparatus of FIG. 3 from upper direction.

  Hereinafter, a thin film forming apparatus according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a sectional view of a thin film forming apparatus 1 according to an embodiment of the present invention, and FIG. 2 is a plan view of one film forming chamber frame of the thin film forming apparatus of FIG. 1 and 2, the same components as those in the conventional configuration shown in FIG. 3 are denoted by the same reference numerals.

  As shown in FIG. 1, a thin film forming apparatus 1 according to this embodiment is an apparatus that forms a thin film on a substrate 2 that is intermittently transported, and includes a film forming chamber 3 for performing a film forming process. Yes. The film formation chamber 3 is disposed so as to face the first film formation chamber wall 3A disposed on one surface side of the substrate 2 and the first film formation chamber wall 3A across the substrate 2. And a second film formation chamber wall 3B.

  As shown in FIG. 1, a hollow high-frequency electrode 4 is disposed inside the first film-forming chamber wall 3A of the film-forming chamber 3, and the high-frequency electrode 4 is used to apply a voltage. It is connected to a high frequency power source 6. On the other hand, a ground electrode 5 is disposed inside the second film formation chamber wall 3B of the film formation chamber 3 so as to face the high frequency electrode 4 with the substrate 2 interposed therebetween.

  As shown in FIGS. 1 and 2, the first film formation chamber wall 3 </ b> A in which the high-frequency electrode 4 is disposed is a block portion 7 having a rectangular frame structure and the substrate 2 side with respect to the block portion 7. A chamber portion 8 and a frame body (frame) 9 disposed on the substrate 2 side with respect to the chamber portion 8 are provided. Here, the high frequency electrode 4 is disposed inside the chamber portion 8, and the frame body 9 is disposed on the chamber portion 8 so as to surround the outer periphery of the high frequency electrode 4.

  As shown in FIG. 1, an insulator 11 is disposed between the chamber portion 8 and the frame body 9 so that the chamber portion 8 and the frame body 9 are electrically insulated. Yes. On the other hand, a spacer 12 is also disposed between the block portion 7 and the chamber portion 8 so that the block portion 7 and the chamber portion 8 are electrically insulated.

  As shown in FIGS. 1 and 2, the frame body 9 is fixed to the chamber portion 8 with a plurality of bolts 10, and the bolts 10 have such a length as to reach the block portion 7 through the chamber portion 8. It is formed with. Here, a cylindrical insulator (not shown) is disposed between the screw portion 10a of the bolt 10 and the chamber portion 8, and the insulation state and block between the chamber portion 8 and the frame body 9 are blocked. The insulation state between the part 7 and the chamber part 8 is maintained.

  As shown in FIG. 1, in this embodiment, the long side part 9a of the frame 9 and the block part 7 are connected by the conductive plate material 13 formed of copper. Further, although not shown in FIG. 1, the long side portion 9b of the frame body 9 and the block portion 7 are similarly connected by a conductive plate material made of copper. In the following description, the conductive plate 13 on the long side 9a side of the frame 9 will be described as an example.

As shown in FIGS. 1 and 2, the conductive plate 13 has a length extending over the long side portion 9 a of the frame body 9, and is rectangular on the opposite side to the chamber portion 8 so as not to contact the chamber portion 8. It is formed to extend.
Further, the frame side end 14 of the conductive plate 13 is fixed to the outer side surface 9c of the frame 9 by screws 15, and the block side end 16 of the conductive plate 13 is fixed to the outer side 7a of the block 7 by screws 17. It is fixed.

Further, as shown in FIGS. 1 and 2, the upper end of the frame-side end portion 14 of the conductive plate member 13 has an extending portion 18 that extends toward the high-frequency electrode portion 4. The extending portion 18 has a length extending over the long side portion 9a of the frame body 9, and is formed in a comb-tooth shape. The extending portion 18 is formed to be curved toward the upper surface 9d of the frame body 9 so as to have elasticity, and the extending portion 18 is in contact with the upper surface 9d of the frame body 9 while maintaining elasticity. Yes.
Here, the conductive plate material 13 on the long side portion 9a side of the frame body 9 has been described as an example. However, as shown in FIG. 2, the conductive plate material on the long side portion 9b side of the frame body 9 also has the extending portion 18. It has the same structure as having.

Next, the flow of current when a voltage is applied to the high-frequency electrode 4 in the thin film forming apparatus 1 of the present embodiment will be described.
When a voltage is applied to the high-frequency electrode 4 in the thin film forming apparatus 1, the current flows toward the lower potential, so the current flows toward the frame body 9 having the lower potential. At this time, since the current is considered to flow at the shortest distance with respect to the frame 9 having a low potential, for example, the current flows toward the long side portions 9 a and 9 b of the frame 9. Here, in this embodiment, since the long side portions 9a and 9b of the frame body 9 and the block portion 7 are connected by the conductive plate material 13, the current flowing through the long side portions 9a and 9b of the frame body 9 is It flows to the block part 7 through the conductive plate 13.
As described above, even when a current flows through the long side portions 9 a and 9 b of the frame body 9, the current can be released to the block portion 7 by the conductive member 13.

  Thus, according to the thin film forming apparatus 1 of the present embodiment, the first film formation chamber wall 3A includes the box-shaped block unit 7, the chamber unit 8 disposed on the block unit 7, and the chamber unit. The chamber portion 8 includes the high-frequency electrode 4 inside, and the frame 9 surrounds the outer periphery of the high-frequency electrode 4. Since the side portions 9 a and 9 b and the block portion 7 are connected by the conductive member 13, when a voltage is applied to the high-frequency electrode 4, when the current flows toward the frame body 9 having a low potential, the current flows to the conductive plate 13. Thus, the block unit 7 is escaped. As described above, since the current can be released not only by the bolt 10 on the frame body 9 but also by the conductive member 13, when the current flows from the substrate 2 toward the frame body 9, the current flows in the portion toward the bolt 10. The current flowing on the substrate 2 can be made uniform without being concentrated. Thereby, the film thickness distribution of the thin film on the substrate 2 can be kept uniform.

  Further, according to the thin film forming apparatus 1 of the present embodiment, the frame body side end portion 14 of the conductive plate material 13 is fixed to the side surface 9a of the frame body 9 with the screw 15, and the block portion side end portion 16 of the conductive plate material 13 is Since it is fixed to the side surface 7 a of the block portion 7 with screws 17, the frame body side end portion 14 of the conductive plate material 13 reliably contacts the frame body 9, and the block side end portion 16 of the conductive plate material 13 also securely contacts the block portion 7. Will come into contact. As a result, the current flowing toward the frame body 9 can be more reliably passed through the conductive plate 13.

  Further, according to the thin film forming apparatus 1 of the present embodiment, the upper end of the frame body side end portion 14 of the conductive plate material 13 is formed to extend to the high frequency electrode 4 side, and the extending portion 18 has elasticity. Since the thin film forming apparatus 1 is repeatedly used and the extension 18 of the conductive plate 13 is extended by heat, the conductive plate 13 and the frame are elastically formed by the elasticity of the extension 18. The contact state with the long side portion 9a of the body 9 is maintained, and as a result, the current flowing toward the frame body 9 can be more reliably passed through the conductive plate member 13.

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

  In the above-described embodiment, the thin film forming apparatus 1 is horizontally arranged as shown in FIG. 1, but the present invention is not limited to this structure, and the thin film forming apparatus 1 may be vertically arranged. In this case, the chamber portion 8 and the frame body 9 are arranged on the front surface side (substrate 2 side) with respect to the block portion 7.

  In the above-described embodiment, the conductive plate 13 is made of copper, but other conductive metals may be used.

  In the above-described embodiment, the block portion 7 is formed in a rectangular frame structure, but is not limited to this structure, as long as it supports the chamber portion and forms the wall of the film forming chamber 3. Other shapes or structures may be used.

DESCRIPTION OF SYMBOLS 1 Thin film forming apparatus 2 Substrate 3 Deposition chamber 3A, 3B Deposition chamber wall body 4 High frequency electrode 5 Ground electrode 6 High frequency power supply 7 Block portion 8 Chamber portion 9 Frame body 9a, 9b Long side portion of frame body 9c Side surface of frame body 9d Upper surface of frame 10 Bolt 10a Screw portion 11 of bolt 11 Insulator 12 Spacer 13 Conductive plate material 14 Frame side end portions 15 and 17 of conductive plate material Screw 16 Block portion side end portion 18 of conductive plate material Extending portion of conductive plate material

Claims (3)

A film forming chamber composed of two box-shaped film forming chamber walls disposed so as to sandwich the substrate, a high frequency electrode disposed on one film forming chamber wall and connected to a high frequency power source, and the other component A ground electrode disposed on the wall of the film chamber and disposed to face the high-frequency electrode, and the reactive electrode is introduced into the film-forming chamber and a voltage is applied to the high-frequency electrode. In a thin film forming apparatus configured to form a thin film on the substrate by performing a plasma discharge between the ground electrode and the ground electrode,
The one film formation chamber wall body includes a block portion, a chamber portion disposed on the substrate side with respect to the block portion, and a frame body disposed on the substrate side with respect to the chamber portion, The portion has the high-frequency electrode therein, the frame surrounds the outer periphery of the high-frequency electrode, and the frame and the block portion are connected by a conductive member. Thin film forming apparatus.   The end of the conductive member on the frame side is fixed to the side surface of the frame with screws, and the end of the conductive member on the block portion side is fixed to the side surfaces of the block portion with screws. The thin film forming apparatus according to claim 1. An upper end of an end portion of the conductive member on the frame body side is formed so as to extend toward the high frequency electrode side, and the extending portion is formed to be curved so as to have elasticity. The thin film forming apparatus according to claim 1 or 2.

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