JPH04280962A - Method for forming heterojunction film and apparatus therefor - Google Patents

Abstract

PURPOSE:To efficiently form a heterojunction film composed of plural films of the different materials on a substrate by executing sputtering and vacuum vapor-depositing in the same vacuum vessel. CONSTITUTION:After closing an upper shutter 6 in a non-sticking source 4 in a vacuum chamber 1 having MgO-made substrate 12 at upper part and providing the electron beam non-sticking source 4 at bottom part, by using two pieces of electrodes 3, 3 fitting a target 7 composed of oxide superconducting material as the target at the tip part, superconducting film made of the target material is formed on the surface of the substrate 12 by sputtering. In this case, it is prevented that the sputtering particles are mixed into the electron beam non- sticking source 4 with existence of the shutter 6. Successively, both the electrodes 3, 3 are retreated and the vacuum chamber is closed with shutters 5, and also the shutter 6 is opened and metal in non-sticking source 4 is vaporized with an electron beam 8 to deposit the metal film on the superconducting film. By repeating this, the heterojunction film of superconducting film and metal film is continuously formed on the substrate 12.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a heterojunction thin film, and more particularly to a method and apparatus for forming a plurality of layers of different types of thin films such as conductive films, metal films, and insulating films on a substrate.

0002

[Prior Art] Conventionally, sputtering methods, vapor deposition methods, etc. are well known as methods for forming metal thin films on substrates. However, when forming a heterojunction thin film, it is necessary to The film is formed by a sputtering method and a multi-source evaporation method using a plurality of evaporation sources for film formation. If single film formation methods such as sputtering and vapor deposition were used in this way, the operations would be complicated to form a heterojunction, and if they were to be formed continuously,
The method is inevitably limited to films with similar film formation conditions, making it impossible to form a variety of heterojunctions. In addition, in order to form a heterojunction film using different film formation methods, it has not been possible to continuously form films in the same chamber, so after creating the first layer film, it must be removed outside the chamber. The common method was to take it out and use another chamber to form a different type of film. For this reason, the surface of the first layer film deteriorated, making it difficult to obtain a steep interface between the films.

0003

[Problems to be Solved by the Invention] Conventional methods have the above-mentioned drawbacks when forming a heterojunction thin film.
In particular, it has not been possible to continuously form diverse heterojunctions. SUMMARY OF THE INVENTION An object of the present invention is to provide a method and apparatus that allow various heterojunctions to be continuously and efficiently formed in the same chamber.

0004

[Means for Solving the Problems] To achieve the above object, the present invention sequentially performs sputtering and evaporation methods in a single vacuum chamber to form various thin films of multiple layers on a substrate. The most important feature is that the In addition, the equipment used to carry out this method is
At the top of the vacuum chamber, a support part for a substrate to be coated with a thin film is provided, an electron beam evaporation source for evaporation is installed at the bottom, and a horizontal electrode for sputtering that can move forward and backward is installed below the upper substrate support part. and a shutter is provided on the evaporation source to prevent sputtered particles from entering the evaporation source during sputtering, and a shutter is provided in the electrode placement portion to close the portion after retreating. It is what it is.

[0005]

[Embodiment 1] FIG. 1 is a sectional view showing an embodiment of the apparatus used for carrying out the method of the present invention, in which 1 is a vacuum chamber;
2 is a substrate support part, 12 is a substrate, 3 is a horizontal electrode, and 4 is a crucible for an electron beam evaporation source for evaporation. In addition, in the drawing, the horizontal electrode on the left side is shown without the sliding mechanism.
The structure is similar to the one on the right. Reference numeral 5 indicates a shutter for closing the electrode portion, and reference numeral 6 indicates a shutter for preventing sputtering particles from entering the evaporation source during sputtering. Note that 7 represents a target and 8 represents an electron beam. Using the reaction chamber shown in Figure 1, Y1 Ba2 Cu3 O7-
Using a target 7 made of a composite oxide with a composition of
Sputtering was performed under the conditions of /O2 = 1 and an applied voltage of 9 kV to form a superconducting thin film on the MgO substrate 12. At this time, the shutter 6 was closed to prevent sputtered particles from entering the evaporation source. After sputtering was completed, both electrode rods were slid to the rear and covered with the shutter 5. After that, open the shutter 6 and set the substrate temperature to 200.
℃ and a reaction pressure of 1×10 −6 Torr or less, Au was evaporated from an electron beam evaporation source installed at the bottom of the chamber, and an Au film was deposited on the superconducting thin film. Next, the shutter 6 was opened, both electrode rods were slid to a position where sputtering could be performed once again, and the superconducting thin film was deposited on the Au film under the same conditions as above. Through this series of operations, it was possible to continuously form a heterojunction film having a structure of superconducting film/metal film/superconducting film on the MgO substrate.

[0006]

[Example 2] Using the reaction chamber shown in Fig. 1, both electrode rods were slid to the rear, covered with the shutter 5, and the shutter 6 was closed, and then the substrate temperature was 400°C and the reaction pressure was 1 x 10-4 Torr. , O2 atmosphere, MgO was evaporated from an electron beam evaporation source installed at the bottom of the chamber, and an MgO film was deposited on the Si substrate. Next, open the shutter 5, close the shutter 6, and slide both electrode rods to the position where sputtering can be performed.
Using a target 7 made of a composite oxide with a composition of 1 Ba2 Cu3 O7-x, the reaction temperature was 550°C, the reaction pressure was 0.1 Torr, Ar/O2 = 1, and the applied voltage was 9.
Sputtering was performed under kV conditions to form a superconducting thin film on the MgO film. After sputtering, slide both electrodes to the rear, close the shutter 5, open the shutter 6, and then increase the substrate temperature to 400°C and the reaction pressure to 1×10
Under the conditions of -4 Torr and O2 atmosphere, MgO was evaporated from an electron and beam evaporation source installed at the bottom of the chamber, and an MgO film was deposited on the superconducting thin film. Furthermore, after that, both electrode rods were slid to a position where sputtering could be performed again, and the superconducting thin film was sputtered under the same conditions as above.
Deposited onto gO film. Through this series of operations, a heterojunction film having a structure of superconducting thin film/insulating film/superconducting film could be continuously formed on the Si substrate via the MgO film.

[0007]

Effects of the Invention As explained above, the method of the present invention allows thin films of different materials under various film formation conditions to be continuously and efficiently formed by performing sputtering and vacuum evaporation in a single vacuum chamber. The effect is extremely large because it enables the formation of various heterojunctions and provides films with new properties.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the configuration of a heterojunction thin film forming apparatus.

[Explanation of symbols]

1 Vacuum chamber 2 Substrate support part 3 Horizontal electrode 4 Electron beam evaporation source for evaporation 5 Electrode shutter 6 Sputtering contamination prevention shutter 12
substrate

Claims (2)

[Claims] 1. Sputtering and evaporation methods are applied to a substrate in a single vacuum chamber in which horizontally opposed sputtering electrodes are arranged at the top and an electron beam evaporation source for evaporation is provided at the bottom. 1. A method for forming a heterojunction thin film, which comprises continuously forming a plurality of thin film layers. 2. A supporting part for a substrate to which a thin film is to be applied is provided at the top of the vacuum chamber, an electron beam evaporation source for evaporation is provided at the bottom, and a sputtering part that can move forward and backward is provided below the substrate supporting part. 1. A heterojunction thin film forming apparatus, comprising: a horizontal electrode disposed; and shutters provided above the electrode arrangement portion and the evaporation source, respectively.