JP2011094165A - Sputtering apparatus and cleaning method - Google Patents

Abstract

A sputtering apparatus that does not require a separate chamber dedicated to pretreatment etching, and further eliminates a drive system dedicated to opening and closing a shutter that protects a target and the like from deposits due to pretreatment etching, and a cleaning method therefor I will provide a.
A multi-cathode type sputtering apparatus in which a plurality of cathodes are arranged in the same chamber, wherein a shield 13 for adhering deposits during pretreatment etching is provided at the position of at least one cathode. .
[Selection] Figure 2

Description

  The present invention relates to a sputtering apparatus for forming a thin film on a surface of a substrate by sputtering, and particularly to a sputtering apparatus for performing a pretreatment for etching the surface of a substrate before film formation and a cleaning method using the same. It is.

  Sputtering apparatuses are actively used in various industrial fields as apparatuses for forming a thin film on the surface of a substrate. In particular, in the manufacture of various electronic devices including LSI, organic EL, TFT, and the like, a sputtering apparatus is frequently used for forming various conductive films and insulating films.

  In such a film formation technique, pre-processing cleaning (hereinafter referred to as pre-processing etching) for etching the surface of the substrate may be performed before film formation. In many cases, the pretreatment etching is a treatment for removing a thin film formed on the surface of the substrate.

For example, a natural oxide film or a protective film may be formed on the surface of the substrate.
When the film forming process is performed in a state where such a thin film is formed, the quality of the formed thin film may be impaired. For example, when a conductive material for wiring is formed in a state where an insulating natural oxide film or protective film is formed on the surface of the substrate, the continuity between the surface of the substrate as a base and the conductive film for wiring There is a problem that makes it worse.

  In addition, when film formation is performed in a state where there is a natural oxide film or a protective film, the adhesion of the thin film to be formed to the substrate may be deteriorated. Furthermore, even when dust or dirt adheres to the surface of the substrate, the adhesion and conductivity of the thin film to the substrate deteriorate.

For this reason, before the film formation, the surface of the substrate is etched to remove foreign substances such as a natural oxide film, protective film, or dust on the surface.
The pretreatment etching is disclosed in, for example, Japanese Patent Laid-Open No. 2002-309370 (Patent Document 1).

JP 2002-309370 A

The pretreatment etching disclosed in Patent Document 1 described above is usually performed in a chamber provided separately from a sputtering chamber for performing sputtering. When pretreatment etching is performed in the sputter chamber, the fine particles of the natural oxide film and protective film released during the pretreatment etching float in the sputter chamber and are mixed into the thin film created during sputtering. This is because the substrate is likely to be stained.
In this specification, such fine particles that contaminate the substrate are collectively referred to as particles.

  The invention of the present application has been made to solve such a problem, and does not require a separate chamber dedicated to pretreatment etching, and further protects targets and the like from deposits due to pretreatment etching. Another object of the present invention is to provide a sputtering apparatus and a cleaning method thereof that do not require a drive system dedicated to opening and closing the shutter.

  In order to achieve the above object, a sputtering apparatus according to the present invention includes a plurality of cathodes in which a film formation processing mechanism for forming a thin film by sputtering and a pretreatment etching mechanism for etching before film formation are performed in the same chamber. Is a multi-cathode type sputtering apparatus characterized in that a shield for adhering deposits at the time of pretreatment etching is provided at the position of at least one cathode.

  Here, the multi-cathode type means that one cathode (or one target) forms one cathode, or a set of cathodes for a plurality of targets of the same type that are sputtered simultaneously. What forms a single cathode means a cathode arranged in a plurality of locations.

  In the sputtering apparatus of the present invention, the substrates are arranged at an angle of 90 degrees along the direction of rotation of the substrate holder so that the thin film is difficult to adhere to both adjacent substrates not facing the target.

In addition, since the shield is fixed in a stationary state at the position where the target is placed, facing the substrate holder that rotates around the rotation axis, the deposits from the substrate attached to the shield during pre-processing etching are , And can be made difficult to be scattered as particles.
Thereby, the problem of particles can be reduced even if pretreatment etching is performed in a sputtering chamber in which sputtering is performed. As a result, it is not necessary to arrange a chamber dedicated to pretreatment etching, which is advantageous in terms of footprint.

It is the side surface schematic diagram at the time of sputtering with the sputtering device of embodiment of this invention. It is the side surface schematic diagram at the time of the pre-processing etching by the sputtering device of embodiment of this invention. It is the schematic seen from the board | substrate holder of the sputtering device of embodiment of this invention.

Hereinafter, embodiments of the present invention will be described.
FIG. 1 is a schematic side view during sputtering by the sputtering apparatus according to the embodiment of the present invention, and FIG. 2 is a schematic side view during pretreatment etching by the sputtering apparatus according to the embodiment of the present invention.
FIG. 3 is a schematic view seen from above the substrate holder of the sputtering apparatus according to the embodiment of the present invention.

Hereinafter, embodiments of the sputtering apparatus of the present invention will be described with reference to FIG. 1 to FIG. 3, but in each of the drawings, the present invention can be understood with respect to the shape, size, and arrangement relationship of each component. It is only schematically shown to the extent. In particular, the size and shape of the substrate and target are only schematically shown.

In the following, preferred configuration examples of the present invention will be described. However, the present invention is not limited to the preferred examples of the present invention, and many modifications and changes can be made without departing from the gist of the present invention. .

  The sputtering chamber 1 is an airtight vacuum container, and the substrate 11 is taken in and out through a gate valve 6 by a substrate transport system (not shown).

The interior of the sputtering chamber 1 can be evacuated to about 10 ⁻⁵ to 10 ⁻⁷ Pa by an unillustrated exhaust system (reference numeral 8 is an exhaust direction). The gas introduction pipe 3 introduces an inert gas such as argon at a predetermined flow rate in the introduction direction 7.
A gas such as argon is introduced through the gas introduction pipe 3, and the sputtering power source 21 is operated in a state where the inside of the sputtering chamber 1 is maintained at a predetermined vacuum pressure by an exhaust system (not shown). Is sputtered to form a thin film of the material of the target 12 on the surface of the substrate 11.

As shown in FIG. 1, the substrate 11 and the target 12 are disposed at opposing positions by the rotation mechanism 23 of the substrate holder 10, and a thin film is formed on the substrate 11 by sputtering in this state.
The substrate holder 10 on which the substrate 11 is installed is electrically insulated from the sputtering chamber 1 by the insulating stone 2. There is a heater 15 inside the substrate holder 10, the substrate temperature is monitored using a thermocouple (not shown), and the electric power supplied to the heater 15 is controlled to control the temperature of the substrate 11. .

  In FIG. 3, three substrates 11 are arranged on the substrate holder 10, two substrates 11 face two targets, and the remaining one substrate 11 faces a shield 13. Yes. The substrate 11 is preferably arranged at an angle of 90 degrees along the rotation direction 14 of the substrate holder 10 in order to make it difficult for the thin film to adhere to both adjacent substrates 11 not facing the target 12. If necessary, an adhesion preventing member can be provided. The shape of the substrate holder 10 is not limited to a cylindrical shape.

Further, the substrate 11 is arranged on the substrate holder 10 by a transport system (not shown). However, in consideration of foreign matters such as particles, the substrate 11 is preferably arranged in an upright state.
A magnet unit (not shown) that enables magnetron sputtering is provided behind the target 11 (on the side opposite to the surface to be sputtered).

  Furthermore, in the sputtering apparatus of the embodiment of the present invention, plasma for pretreatment etching with respect to the substrate 11 can be formed between the substrate 11 and the shield 13 by the discharge by the sputtering power source 21.

  That is, when pre-processing etching is performed before film formation by sputtering, as shown in FIG. 2, the power from the sputtering power source 21 is applied to the substrate 11 via the substrate holder wiring 24 by the switch 22. Pretreatment etching can be performed.

  Here, since the shield 13 is fixed in a stationary state at a position where the target is disposed, facing the substrate holder 10 rotating around the rotation axis, the pretreatment etching from the substrate 11 attached to the shield 13 is performed. The adhering material at the time has a structure that is difficult to be scattered as particles. The shield 13 itself has a replaceable configuration.

  In the configuration of the above embodiment, the shield 13 may have a configuration in which an insulating layer is provided on a metal body, or the entire shield 13 may be made of an insulator.

  That is, the whole may be formed of ceramics or other insulators such as alumina or glass (quartz glass or the like). Further, in the case of the shield 13 made entirely of an insulator, even if the shield 13 is short-circuited to the ground 5, a potential difference may be formed inside or it may become electrically unstable. Such a problem is less when the insulating layer is formed on the metal member.

With the above-described configuration, the pretreatment etching in the sputtering apparatus of the present embodiment is performed, for example, by exhausting the inside of the sputtering chamber 1 to about 10 ⁻⁵ to 10 ⁻⁷ Pa by an unillustrated exhaust system and predetermined by the gas introduction pipe 3. The pretreatment etching can be performed by introducing the argon gas at the flow rate and operating the sputtering power source 21.

1. Sputtering chamber
2. Insulating stone
3. Gas introduction piping
4. Exhaust system
5. Earth
6. Gate valve
7. Gas introduction direction
8. Exhaust direction
10. Board holder
11. Board
12. Target
13. Shield
14. Direction of rotation of substrate holder
15. Heater
21. Sputtering power supply
22. Switcher
23. Rotating mechanism
24. Wiring for board holder
25. Target wiring

Claims (3)

  A multi-cathode type sputtering apparatus in which a plurality of cathodes are disposed in the same chamber, wherein a film forming process mechanism for forming a thin film by sputtering and a pre-process etching mechanism for performing etching before the film forming process are provided, A sputtering apparatus, wherein a shield for adhering deposits at the time of the pretreatment etching is provided at a position of the one cathode.   2. The sputtering apparatus according to claim 1, wherein the shield is in a standing state facing the substrate during the pretreatment etching. A cleaning method using the sputtering apparatus according to claim 1.