JPH02179870A - Thin film forming device - Google Patents

Abstract

PURPOSE:To efficiently form the films on a plurality of base plates in the respective different conditions by thoroughly shielding the base plates with a shutter and performing presputtering and thereafter exposing only the required base plate to perform sputtering. CONSTITUTION:A plurality of base plates 2 are attached to a base plate table 4 rotatable around a rotary shaft 4a by a rotating mechanism 3 in an exhaustible vacuum vessel 1. A target 5 is arranged oppositely to the base plates 2. Furthermore a shutter 17 is arranged to the intermediate position between the base plates 2 and the target 5 so that the shutter 17 can be rotated around a hollow shutter shaft 17c by a rotating mechanism 18. In a thin film forming device having the above-mentioned constitution, voltage is impressed to the target 5 from a power source 6 to generate plasma and presputtering of the target 5 is performed in such a state that the base plates 2 have been thoroughly shielded by the shutter 17. Thereafter the required base plate 2 is arranged to the prescribed position and exposed by transferring the shutter 17 and film formation is performed. Thereby film formation is performed on the base plates 2 at every arbitrary sheet thereof in the arbitrary conditions by sputtering of one time without opening the vacuum vessel 1.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is a thin film forming apparatus using a sputtering method, which includes a substrate table on which a plurality of substrates on which thin films are to be formed are attached in a vacuum container, and a target to be a thin film material. The sputtering gas is introduced into the container by placing the shutters facing each other and placing a shutter at an intermediate position between the substrate table and the target so that the substrate is shielded from the target.
It relates to thin film forming equipment that applies voltage from a plasma generation power supply between a target and a substrate to generate plasma, and opens a shutter while sputtering the target to form a thin film on the substrate. The present invention relates to the configuration of a thin film forming apparatus.

[Conventional technology]

An example of a conventional configuration of this type of thin film forming apparatus is shown in FIG. A substrate 2 on which a thin film is to be formed is mounted in a vacuum container 1, and a substrate table 4 equipped with a substrate table rotation mechanism 3 on the atmosphere side of the vacuum container 10 and a target 5 to be a thin film material are placed facing each other. A shutter 7 is arranged between the table 4 and the target 5, and sputtering gas is introduced into the container, and the flow rate of the sputtering gas is adjusted so that the pressure inside the container is maintained at a degree of vacuum suitable for the film forming conditions. With the shutter 7 closed, voltage is applied to the target 5 from the plasma generation power source 6 to generate plasma in the space between the shutter 7 and the target 5, which is at ground potential, and the target 5 is sputtered by this plasma. . Thereafter, the shutter 7 is opened at an appropriate time to generate plasma in the space between the substrate table 4 and the target 5, which are at ground potential, to form a thin film on the substrate 2. A shutter 7 disposed between the substrate 2 and the target 5 prevents sputtered particles ejected from the target 5 from adhering to the substrate 2 while the shutter 7 is closed. Usually, an impurity layer is formed on the target surface layer due to moisture, oxygen, etc. adsorbed when exposed to the atmosphere, and these impurities are removed before film formation because they cause deterioration of the quality of the thin film that is formed. There is a need. Generally, as described above, plasma discharge is first started with the shutter closed, and the impurity layer on the target surface is removed by sputtering by the plasma generated in the space between the shutter 7 and the target 5. This process is called pre-sputtering, and after pre-sputtering for a certain period of time, the shutter is opened.
A thin film is formed on a substrate. In conventional thin film forming equipment that has a substrate table on which multiple substrates can be attached at once, the shutter has a structure that covers the target or the entire substrate table on which the substrates are installed. It is used.

[Problem to be solved by the invention]

As described above, problems with the shutter structure that covers the target or the shutter that covers the entire substrate table are as follows. In other words, all the substrates placed on the substrate table can only be sputtered under the same conditions to form thin films; in order to obtain thin films sputtered under different conditions,
Every time sputtering under one condition is completed, the vacuum chamber must be opened to the atmosphere, the substrate must be replaced, and then evacuation and pre-sputtering must be performed again.

Particularly in research and development, it is often necessary to use small quantities of substrates on which thin films are sputtered under different conditions. In such cases, repeating the steps of evacuation and pre-sputtering is not only a waste of time, but frequent pre-sputtering also shortens the usable time of the target, leading to the problem that the target must be replaced more frequently. Ta.

The purpose of the present invention is to pre-sputter all of a plurality of substrates attached to a substrate table without opening a vacuum container, and to perform film deposition for each desired number of substrates or any number of substrates each time under different sputtering conditions. An object of the present invention is to provide a thin film forming apparatus capable of performing the following steps.

[Means to solve the problem]

In order to solve this problem, in the present invention, a substrate table on which a plurality of substrates on which thin films are to be formed are placed facing each other in a vacuum container, and a target to be made into a thin film material are placed facing each other. Sputtering gas is introduced into the container by placing a shutter at an intermediate position so that the substrate is shielded from the target, and a voltage is applied from the plasma generation power supply between the target and the substrate to generate plasma, and the target In a thin film forming apparatus that forms a thin film on a substrate by opening a shutter while sputtering, the shutter is used to shield all of the plurality of substrates from the target during pre-sputtering prior to forming a thin film on the substrate, Sometimes, only a desired substrate out of a plurality of substrates is exposed to the target while the remaining substrates are shielded from the target, and a shutter operation means for operating the shutter is disposed outside the vacuum chamber, and It shall be possible to operate the shutter from

[Effect]

By configuring the thin film forming apparatus in this way, it is possible to perform sputtering under at least two different conditions by operating only from the atmosphere side and without opening the vacuum container to the atmosphere. It is possible to reduce the number of vacuum evacuations and pre-sputtering steps required to obtain the desired results, significantly improving the efficiency of research and development.

〔Example〕

FIG. 1 shows a first embodiment of a thin film forming apparatus equipped with a shutter mechanism of the present invention. In this embodiment, the shutter operation means for operating the shutter so that all of the plurality of substrates are shielded from the target during pre-sputtering and only desired substrates are exposed to the target during sputtering is the substrate table 4.
placed on the same axis. Shutter 17, detailed below
A shutter rotation mechanism 8 for rotationally driving the shutter 17 is formed independently of the rotation mechanism 3 of the substrate table 4, and rotates the shutter 17 via a hollow shutter shaft 17c that hermetically passes through the vacuum container 1. The airtight seal member 1 is used to maintain airtightness between the inner diameter side of the shutter shaft 17c and the rotating shaft 4a of the substrate table 4.
2 is maintained.

FIG. 2 shows the structure of the shutter 17. The shutter 17 is
A shirt plate 17a made of a metal disc, a flat circular case-shaped shirt plate made of an insulating material and a mounting base 17b,
This installation is performed using an insulating hollow shaft 17 formed integrally with the stand 17b.
c, and covers the entire substrate table 4. In this figure, four boards are attached as an example. Openings 11 are formed in the shirt cover plate 17a so that one substrate is completely exposed, the number of openings is the same as the number of substrates to be deposited under one condition, and the positions thereof are the same as the number of substrates to be deposited under one condition. The position is such that only the substrate is properly exposed and the other substrates are reliably covered.

In order to start selective film formation using such a shutter, first, the position of the opening 11 of the shutter plate 17a is adjusted by the shutter rotation mechanism 8 (Fig. 1) to any substrate as shown in Fig. 2. It is not exposed and is fixed at a position closest to the film forming substrate 2. Thereafter, the substrate table 4 and shutter 17 are simultaneously moved so that the film-forming substrate is positioned in front of the target, and pre-sputtering is started. After the pre-sputtering is completed, the opening 11 is moved via the shortest distance to a position where the film forming substrate is completely exposed as shown in FIG. 3, and a film is formed on the substrate. After the desired film-forming time has elapsed, sputtering is terminated. When forming a film on a second substrate under different conditions, the same process is repeated by moving the opening to a position closest to that substrate and not exposing any substrate. When depositing films on two or more substrates under the same conditions, prepare a shutter plate with openings at positions that expose all the desired substrates at the same time, and then move the openings after pre-sputtering is completed. However, the substrate table and the shutter may be rotated at the same rotation speed at the same time when the film-forming substrate is completely exposed and sputtering begins. FIG. 4 shows an example of a shutter plate used when forming films on two substrates at the same time.

A second embodiment of the present invention is shown in FIGS. 5 and 6. In this embodiment, the shutter is configured such that a shutter plate covers each of the substrates independently, and each can be opened and closed independently. That is, as shown in FIG. 6(a), the shutter plate 27a is formed as a metal disk slightly larger than the substrate 2, and the operating rod 27c (fifth
A desired substrate 2 is exposed to the target 5 via the opening/closing lever 27b by rotationally driving the substrate 2 shown in FIG. The operating rod 27c is supported rotatably about its own axis on both the upper and lower end surfaces of the hollow insulated drive shaft 27d, and an airtight seal member 27e is used on the upper end surface of the hollow insulated drive shaft 27d to close the hollow insulated drive shaft 27d. Airtightness is maintained between the inner diameter side and the circumferential surface of the operating rod 27c. After exposing the desired substrate, the insulated drive shaft 27d is rotated by the shutter rotation mechanism 18 at the same rotation speed as the substrate table rotation speed by the substrate table rotation mechanism 13. In this way, a plurality of substrates on the substrate table can be pre-sputtered all at the same time, and each time a different number of substrates can be deposited under different sputtering conditions.

〔Effect of the invention〕

As described above, according to the present invention, a substrate table on which a plurality of substrates on which thin films are to be formed are placed in a vacuum container and a target to be a thin film material are placed facing each other, and the substrate table and the target are arranged to face each other. Sputtering gas is introduced into the container by placing a shutter at an intermediate position so that the substrate is shielded from the target, and a voltage is applied from a plasma generation power supply between the target and the substrate to generate plasma, and the target In a thin film forming apparatus that forms a thin film on a substrate by opening a shutter while sputtering, all of the plurality of substrates are shielded from the target during pre-sputtering prior to forming a thin film on the substrate, and the sputtering for forming the thin film is performed. In some cases, only a desired substrate out of a plurality of substrates is exposed to the target while the remaining substrates are shielded from the target, and a shutter operation means for operating the shutter is disposed outside the vacuum chamber, so that the vacuum It is possible to form films under at least two different sputtering conditions without exposing the container to the atmosphere, reducing the number of evacuations and pre-sputtering required to obtain the desired sample, and shortening the operating time of the equipment. , the efficiency of research and development is improved, and the frequency of target replacement is reduced, resulting in improved utilization efficiency.

[Brief explanation of the drawing]

FIG. 1 is an explanatory cross-sectional view showing a configuration example of a thin film forming apparatus equipped with a shutter and its operation means according to a first embodiment of the present invention, and FIG. 2 shows a configuration of the shutter in the embodiment of FIG. 1. (a) is a plan view. ] is a side sectional view of the main part, FIG. 3 is a plan view showing the positional relationship during sputtering between the shutter plate and the substrate table in the shutter configuration of FIG. 2, and FIG. FIG. 5 is a plan view showing the structure of a shutter plate that enables film formation on two substrates at the same time, and FIG. FIG. 6 is a plan view showing the configuration of the shutter in the embodiment shown in FIG. 5, and (a) is a diagram showing the state of the shutter during pre-sputtering.
(c) is a diagram showing the state of the shutter during sputtering. FIG. 7 is an explanatory cross-sectional view showing a configuration example of a conventional thin film forming apparatus equipped with a shutter. ■ Vacuum container, 2 Substrate, 4.14 Substrate table, 5
Target, 6 Power supply (power supply for plasma generation), 7
．． 17.27 Shutter, 8, 18 evening rotation mechanism (nyatta operation means). Shirt Figure 1 (a) Figure Figure Figure Figure Figure Procedure Amendment (0ri 1. Indication of Case Patent Application Sho I, 3-J, itJ', 3/3, Person Making Amendment Case and Related address name

Claims (1)

[Claims] 1) A substrate table on which a plurality of substrates on which thin films are to be formed are placed in a vacuum container and a target to be formed into a thin film are placed facing each other, and a shutter is placed at an intermediate position between the substrate table and the targets so that the substrates are shielded from the targets. A sputtering gas is introduced into the container, and a voltage is applied between the target and the substrate from a plasma generation power source to generate plasma. While sputtering the target, the shutter is opened and a thin film is deposited on the substrate. In a thin film forming apparatus for forming a thin film, the shutter shields all of the plurality of substrates from the target during pre-sputtering prior to forming a thin film on the substrate, and shields only a desired substrate among the plurality of substrates during sputtering for thin film formation. 1. A thin film forming apparatus, characterized in that the thin film forming apparatus is formed to be able to expose the remaining substrate to the target and to shield the remaining substrate from the target, and a shutter operating means for operating the shutter is disposed outside the vacuum chamber.