JP2006161095A - Film deposition apparatus and film deposition method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a film deposition apparatus and a film deposition method which enable pre-treatment such as pre-sputtering in a vacuum vessel to be performed without arranging complicated shutter mechanism. <P>SOLUTION: The film deposition apparatus performs film deposition in such a manner that a plurality of trays 4 are shifted in order to each of the plurality of vacuum vessels 1 connected in series and film-depositing treatment is applied to a work 6 held with the tray 4 in each vacuum vessel 1, wherein each of the plurality of trays 4 has constitution having, in at least the end parts, projecting parts 10 functioning as blocking parts for holding a prescribed atmosphere in the vacuum vessel 1 with conductance by blocking opening holes 2a disposed at both end parts of the vessel so as to leave a gap permissible to pass the tray 4 itself therethrough when the tray is set at a prescribed film-depositing position in each vacuum vessel 1. Some trays among the plurality of trays 4 are used as dummy trays 4b which do not convey the work 6, and the pre-deposition treatment is performed in the vacuum vessel 1 into which the dummy tray 4b is shifted. The individual atmosphere can be held in each vacuum vessel 1 by hermetically sealing the vacuum vessel with the tray 4 itself functioning as the shut-off means. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a film forming apparatus and a film forming method for performing a film forming process such as sputtering on an object to be processed in a vacuum chamber.

  As an example of the film forming apparatus, FIG. 5 shows a sputtering apparatus. In this sputtering apparatus, a target 13 is placed on a cathode 12 in a vacuum chamber 11, and a workpiece 14 is placed on a stage (not shown) via a tray 15 (or holder) or directly so as to face the target 13. In this state, an inert gas such as Ar is introduced into the vacuum chamber 11, the inside of the chamber is adjusted to a predetermined pressure, and then DC power or high-frequency power (depending on the target material) is applied to the cathode 12. The plasma discharge P1 is generated between the workpiece 14 and the target 13, the target 13 is sputtered, and the sputtered target material is deposited on the workpiece 14 to form a thin film.

  Since the surface of the target 13 is oxidized during the stand-by of the apparatus or impurities other than the target material adhere to the surface due to the plasma discharge P1, as shown in the figure, the target 13 moves linearly or swivels between the target 13 and the workpiece 14 A shutter 16 that cuts between the two is installed, and plasma discharge P1 is generated between the target 13 and the shutter 16 prior to the film forming process to remove oxides and deposits on the surface of the target 13. Pre-sputtering is performed. The shutter 16 has a function of preventing dust or the like generated in the pre-sputtering process from adhering to the inside of the vacuum chamber 11 or the work 14.

  In the conventional sputtering apparatus, since the shutter is operated in the vacuum chamber as described above, a complicated mechanism such as a vacuum seal of the shutter driving unit and a structure for preventing dust generation due to the shutter operation is necessary. However, in recent years, as the parts to be manufactured, such as optical parts and MEMS (micro electro mechanical system), have been downsized, the film deposition system has been required to be compact (desktop size) and simplified. It has become difficult to provide.

  In view of the above problems, an object of the present invention is to provide a film forming apparatus and a film forming method capable of performing pretreatment such as pre-sputtering in a vacuum chamber without providing a complicated shutter mechanism.

  In order to achieve the above object, the film forming apparatus of the present invention sequentially transfers a plurality of trays to each of a plurality of vacuum chambers connected in series, and forms a work held on the tray in each vacuum chamber. In the film forming apparatus that performs film processing, each of the plurality of trays closes the opening at both ends of the tank leaving a gap that allows the tray itself to pass when the trays are arranged at predetermined film forming positions in each vacuum tank. In addition, at least one end of the plurality of trays has a closed portion that maintains a predetermined atmosphere in the vacuum chamber due to conductance, and a part of the plurality of trays is a dummy tray that does not transfer workpieces, and the vacuum to which the dummy tray is transferred A predeposition process is performed in the tank.

  Further, the film forming method of the present invention is a film forming method in which a plurality of trays are sequentially transferred to each of a plurality of vacuum chambers connected in series, and a film forming process is performed in each vacuum chamber on a work held on the tray. The plurality of trays are closed at a predetermined film formation position in each vacuum chamber, and the openings at both ends of the chamber are closed leaving a gap that allows the tray itself to pass through, and the conductance creates the inside of the vacuum chamber. A tray having at least an obstructing portion for maintaining a predetermined atmosphere is transported including a dummy tray that does not transport a workpiece, and predeposition processing is performed in a vacuum chamber to which the dummy tray is transported. And

  According to the film forming apparatus and the film forming method described above, each atmosphere can be maintained in each vacuum chamber by using the tray itself as a sealing means, and the dummy tray can be used as a shielding means in the vacuum chamber to which the dummy tray is transferred, or a dummy The same state in the tank as that during film formation can be realized by the tray, and a predetermined predeposition process can be performed. Therefore, a complicated shutter mechanism as in the prior art is not necessary, and the apparatus can be simplified.

The pre-deposition process may be a pre-sputter process that removes oxides and impurities on the target surface before film formation by sputtering.
What is necessary is just to increase / decrease a dummy tray according to the kind of workpiece | work and film-forming conditions. This is because the number of predeposition processes is set by the number of dummy trays.

  By alternately arranging the transfer tray and the dummy tray, film formation and predeposition processing can be performed alternately. For example, in sputtering, since oxides and impurities on the target surface are usually removed for each film formation process, it can be said to be a process suitable for that.

  According to the film forming apparatus and the film forming method of the present invention, a predetermined predeposition process can be performed without providing a complicated shutter mechanism. The apparatus can be simplified without eliminating the functions required for the process.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional view showing a schematic configuration of a film forming apparatus according to the first embodiment of the present invention.
This film forming apparatus is configured as a sputtering apparatus, and a plurality of vacuum chambers 1 are connected in series for the purpose of sequentially performing a plurality of different types of film forming processes.

  The plurality of vacuum chambers 1 are separated from each other by a partition wall 2 having an opening 2a in the center, and two cathodes 3 (including a target) are disposed facing each other, and the plurality of trays 4 are vacuum chambers. 1 are sequentially moved along the arrangement direction of 1, arranged at predetermined film forming positions between the cathodes 3 in each vacuum chamber 1, and formed on both the front and back surfaces of the work 6 held in the through holes 5 of the tray 4. It has a structure in which film treatment is performed.

  Each vacuum chamber 1 employs a magnetron sputtering method, and generates a large amount of ions in the vicinity of the cathode 3 by magnetron discharge to increase the deposition rate. The earth shield 7 covering the periphery of the cathode 3 is provided with an opening 7a through which the tray 4 can pass so that only the surface of the cathode 3 facing the work 6 is discharged. 8 is an evacuation system and 9 is an air supply system.

  The plurality of trays 4 include a transport tray 4 a having the above-described through holes 5 and dummy trays 4 b used for predeposition processing described later, and guide rollers provided on the inner surface of the vacuum chamber 1, respectively. It moves while being regulated by the position (not shown).

  Projections 10 projecting in the direction along the partition wall 2 are formed with dimensions slightly smaller than the opening 2a at the front end and the rear end in the moving direction of each tray 4 (4a, 4b). When the projection 10 is disposed at a predetermined film-forming position in 1, the projection 10 closes the opening 2 a leaving a slight gap allowing the passage of the projection 10. Without providing a gate valve for sealing the vacuum chamber 1, a predetermined atmosphere is maintained in each vacuum chamber 1 using conductance (an amount indicating the ease of gas flow in the tube). Usually, a differential pressure is applied to both ends of the vacuum chamber 1 by supplying an appropriate amount of air to each vacuum chamber 1 from an individual air supply system 9 while exhausting from each vacuum chamber 1 by a single vacuum exhaust system 8. Cause it to occur.

Hereinafter, a film forming method in the above-described film forming apparatus will be described.
In FIG. 1, a dummy tray 4 b is disposed in the most downstream vacuum chamber 1, and a transport tray 4 a holding a workpiece 6 is disposed in the two upstream vacuum chambers 1.

  In this state, an inert gas such as Ar is introduced into each vacuum chamber 1 and the inside of each vacuum chamber 1 is adjusted to a predetermined pressure, and then direct current power or high frequency power (determined by the target material) is applied to each cathode 3. In the two vacuum chambers 1 on the upstream side, a plasma discharge P1 is generated between the workpiece 6 and the cathode 3 to sputter the cathode 3 (target), and the sputtered target material is A thin film is formed by depositing on the workpiece 6. In the most downstream vacuum chamber 1, plasma discharge (pre-sputter discharge) P <b> 2 is generated between the cathode 3 and the dummy tray 4 b to perform pre-sputtering, thereby removing oxides and impurities on the surface of the cathode 3.

  Next, the dummy tray 4b and the transfer tray 4a are transferred through the state shown in FIG. 2, and a film forming process is performed in the vacuum chamber 1 in which the workpiece 6 is transferred. Dust generated by the pre-sputtering process is exhausted through the vacuum exhaust system 9 or attached to the dummy tray 4b and carried out.

  Thereafter, in the same manner, the tray 4 (4a, 4b) is transferred, the film 6 is formed on the workpiece 6 in the vacuum chamber 1 in which the transfer tray 4a is loaded, and the inside of the vacuum chamber 1 in which the dummy tray 4b is loaded. Pre-sputtering is performed at

  In this way, in a film forming apparatus that sequentially transfers a plurality of workpieces 6 to a plurality of vacuum chambers 1 and performs a film forming process, a complicated shutter mechanism is provided without providing a vacuum valve for sealing each vacuum chamber 1. Without being provided, the film forming process and the pre-sputtering process can be performed in parallel, and the film forming apparatus can be simplified. When the same process is arranged in a plurality of vacuum chambers 1, there is no difference in processing time. However, when another process is arranged, the process is limited to a process having a long time.

  The frequency of the pre-sputtering process can be arbitrarily set by arranging dummy trays 4b at arbitrary intervals between the plurality of transfer trays 4a. For example, by placing one dummy tray 4b after ten transfer trays 4a holding the workpiece 6, it is possible to set one pre-sputtering process every time ten film formations are completed. . However, each vacuum chamber 1 does not necessarily have to perform the pre-sputtering process when the dummy tray 4b is arranged.

FIG. 3 is a cross-sectional view showing a schematic configuration of a film forming apparatus according to the second embodiment of the present invention.
In this film forming apparatus, the transfer trays 4a and the dummy trays 4b are alternately arranged. Such a configuration is practical because it is desirable to perform the pre-sputtering process every time film formation is completed, and even in the present situation, it is often performed at such a frequency.

FIG. 4 is a sectional view showing a schematic configuration of a film forming apparatus according to the third embodiment of the present invention.
In this film forming apparatus, the tray 4 has a size equivalent to two of the vacuum chamber 1, and the workpiece 3 is held in the rear half in the traveling direction of the tray 4, so that the dummy tray described above is placed in the front half of the tray 4. It has the same function as 4b.

  In the film forming apparatus shown in FIGS. 1 to 4 described above, two cathodes 3 are installed facing each other in the vacuum chamber 1, and the tray 4 (4 a, 4 b) is transferred between them to form both the front and back surfaces of the work 6. Although the film is formed, the pre-sputtering process can be similarly performed by using the transfer tray and the dummy tray even in the film forming apparatus having one cathode as described with reference to FIG. . The transfer of the tray 4 (4a, 4b) is not limited to the above-described means.

  Further, when film formation is not performed by sputtering, for example, when film formation is performed by CVD, by transferring the transfer tray and the dummy tray in the same manner as described above, the tray itself is used as a sealing means for each vacuum chamber. In addition to being able to maintain the atmosphere, pre-deposition processing that performs plasma discharge for the purpose of adjusting the atmosphere in the tank is realized in the vacuum tank to which the dummy tray has been transferred, realizing the same arrangement as in the film formation. Can do.

  The film forming apparatus and the film forming method of the present invention realize a compact and simple apparatus configuration capable of preprocessing such as pre-sputtering without using a complicated shutter mechanism, and are small in size such as optical components and MEMS. Particularly useful in the manufacture of parts.

1 is a schematic configuration diagram of a film forming apparatus according to a first embodiment of the present invention. Schematic configuration diagram showing the state of the film forming apparatus of FIG. Schematic configuration diagram of a film forming apparatus in a second embodiment of the present invention Schematic configuration diagram of a film forming apparatus according to a third embodiment of the present invention. Schematic configuration diagram of conventional film deposition equipment

Explanation of symbols

1 Vacuum chamber 2 Bulkhead
2a Opening 3 Cathode 4 Tray
4a Transport tray
4b Dummy tray 6 Workpiece
10 Protrusion (occlusion)
P1 Plasma discharge
P2 Pre-sputter discharge

Claims (5)

In a film forming apparatus that sequentially transfers a plurality of trays to each of a plurality of vacuum tanks connected in series, and performs a film forming process in each vacuum tank on a work held on the tray,
When the plurality of trays are arranged at predetermined film formation positions in each vacuum chamber, the openings at both ends of the chamber are closed leaving a gap that allows the tray itself to pass through, and a predetermined conductance is provided in the vacuum chamber by conductance. And at least one end of the plurality of trays is a dummy tray that does not carry workpieces, and predeposition processing is performed in a vacuum chamber to which the dummy trays are transferred. A film forming apparatus configured as described above.   The film forming apparatus according to claim 1, wherein the predeposition process is a presputter process for removing oxides and impurities on the target surface before film formation by sputtering.   The film forming apparatus according to claim 1, wherein the number of dummy trays is increased or decreased in accordance with the type of work and the film forming conditions.   The film forming apparatus according to claim 3, wherein the transfer tray and the dummy tray are alternately transferred. In the film forming method of sequentially transferring a plurality of trays to each of a plurality of vacuum tanks connected in series, and performing a film forming process in each vacuum tank on a work held on the tray,
When the plurality of trays are arranged at predetermined film forming positions in each vacuum chamber, the openings at both ends of the chamber are closed leaving a gap that allows the tray itself to pass through, and a predetermined conductance is provided in the vacuum chamber by conductance. A film forming method in which a tray having a closed portion for holding an atmosphere at least at an end thereof is transferred including a dummy tray that does not transport a workpiece, and a predeposition process is performed in a vacuum chamber to which the dummy tray is transferred.

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