JPH02217464A - Vacuum deposition equipment - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a vacuum evaporation apparatus for depositing a thin film consisting of a plurality of components at a constant composition ratio onto the surface of a substrate.

Conventional techniques For example, thin film materials with different vapor pressures1. The composition ratio of Mu2 is L
When an alloy that is AT' Li2 is melted in a crucible and vacuum-deposited on a substrate, the composition ratio of the thin film material of the thin film formed on the substrate is 'AT''A2, and when the vapor pressure of Li2 is higher. With the passage of time, the value of the formula 'A2 / ('l + '12) representing the composition ratio of Mu2 in the thin film and the value of the formula Ll / (LAI
+LA2) both decrease as shown in FIG. Therefore, the target composition ratio range of the thin film is y as shown in the figure.
In this case, film formation must be completed within a correspondingly short time T/.

As a conventional technique for obtaining a thin film with a target composition ratio over a long period of time, for example, Japanese Patent Application Laid-Open No. 63-58622 discloses that when an alloy of Coo and Or is deposited, only Or having a high vapor pressure is supplied. What to do is presented. If only the material with higher vapor pressure is replenished, the amount of molten metal in the crucible will decrease over time. If you do not want the amount of molten metal to decrease,
In particular, if you want to maintain the amount of molten metal constant, if the evaporation amount per unit time of Go and Or is No and Wr, respectively, then G
It is sufficient to replenish Wo and Wr per hour for o and cr '6, respectively. The shape of the material to be replenished may be granular or rod-like.

Problems to be Solved by the Invention However, the above-mentioned conventional vacuum evaporation method causes the following problems.

In FIG. 4, 1 is a container for example Go
Although not shown in the drawings, it is heated into a molten metal by, for example, a well-known electron beam or the like. 3 is a 2t crucible - a cooling hearth.

A cooling water passage 4 is formed inside. Figure ε(mu)～
(Fl is a film 6 formed by the vapor generated from the Cj o -Or alloy 1 adhering to the surface of the crucible 2 located above the surface of the molten co-Orr alloy 1 shown in Fig. 4, and as time passes. The film thickness increases, and then the molten Cjo-Or alloy 1 comes into contact with the film 6, and the film 6 melts into the molten Go-Orr alloy 1.

In Figure 6), the film 6 attached to the surface of the glass 2 increases in thickness as time passes, as shown in Figure 6). The material for keeping the composition ratio of the thin film to be formed constant at that time is, for example, Co-Or as shown by the arrow in FIG.
When the molten metal of Alloy 1 is supplied, the surface of the molten metal shakes due to the disturbance caused by the supply operation, and the molten metal comes into contact with the film 5 as shown in FIG. is melted (in Figure 6), Figure 6 (3),
As shown in FIG. 6(3), the melt is poured into the molten metal in the direction of arrow B until almost no film 6 remains.

Since the vapor pressure of Or is higher than that of Co, the concentration of Or in the film 6 is 4 to 6 times that of the molten metal. Therefore, when the film 6 melts into the molten metal, the Or concentration of the molten metal increases, and the Or concentration of the thin film formed thereby also increases.
It was difficult to maintain a constant composition ratio of o and Or.

SUMMARY OF THE INVENTION In view of the above-mentioned conventional problems, an object of the present invention is to provide a vacuum evaporation apparatus that can perform evaporation while maintaining a constant composition ratio.

Means for Solving the Problems In order to solve the above problems, the vacuum evaporation apparatus of the present invention includes a crucible made of an insulator that stores a plurality of thin film materials having different vapor pressures, and a crucible in which the vapors of the thin film materials are attached. A first heating means for heating the thin film material in the crucible is installed in a vacuum container in which a substrate on which a thin film is formed, and a first heating means for heating the thin film material in the crucible, and a first heating means for heating the thin film material heated by the first heating means and adhering to the surface of the crucible. The device is constructed by providing a high-frequency heating means for heating and re-vaporizing the thin film formed by the vapor.

Function: With the above-described structure, the present invention can re-evaporate the thin film attached to the surface of the melt, thereby preventing a thin film having a composition ratio different from that of the molten metal from penetrating into the molten metal.

Therefore, it becomes possible to deposit a thin film with a constant composition ratio on the substrate.

EXAMPLE Hereinafter, a vacuum evaporation apparatus according to an example of the present invention will be explained based on the drawings.

FIG. 1 is a structural diagram of an embodiment of the present invention. Note that the same components as in the conventional example are given the same numbers.

In the figure, reference numeral 6 denotes a coil supplied with high frequency power from a high frequency power source 7, which inductively heats the conductor around the coil. Reference numeral 8 denotes a substrate on which a thin film 9 is to be formed, and is supported at the upper part of the vacuum vessel 11 by a substrate holder 1o. Reference numeral 12 denotes a shield for preventing the high frequency waves generated from the coil 6 from escaping from the vicinity of the coil #Y2 and causing problems such as acting on the thin film 9 and heating the thin film 9, for example.

In addition, if there is no risk of such inconvenience, use Shield 1.
2 can be omitted. Further, in FIG. 1, a known evacuation means for evacuating the vacuum container 11 and, for example, a known electron beam heating means for heating the thin film material 1 are omitted. In the configuration of this embodiment, the crucible 2 is made of an insulator.

Furthermore, although the cooling means for the coil 6 and the shield 12 are omitted, if large high-frequency power is required, a water-cooled structure may be used to prevent overheating, as in the case of the hearth 3.

Next, the operation of the apparatus of this embodiment will be explained.

For example, a part of the vapor generated when a thin film material made of Co-Cr alloy 1 is heated by an electron beam heating means etc. adheres to the substrate 8 to form a thin film 9, and the other part of the vapor is shown in FIG. As shown, a film 6 is deposited on the upper edge surface of the crucible 2 as in the conventional case.

The high frequency current flowing through the coil 6 generates an induced current in the conductor around it, and the higher the frequency, the more densely the induced current flows closer to the surface of the conductor due to the so-called skin effect.

Therefore, the vicinity of the surface of the conductor portion shown by the bold line in FIG. 2 is heated intensively. The film S whose temperature increases the most due to this heating is the conductor with the largest (surface area/volume), that is, the conductor with the largest (calorific value/volume).

Therefore, as soon as the membrane 5Il'i adheres to the surface of the crucible 2, it is quickly heated, the temperature rises, and it is quickly re-evaporated, which prevents the conventional problem of the membrane 6 from penetrating into the molten metal (see Figure 5). Fluctuations in the composition ratio of the thin film 9 can be resolved.Although the present embodiment uses an electron beam to heat the thin film material 1, the heating means of the present invention is not limited to this. Alternatively, a high-frequency induction heating means that can heat the thin film material 1 from inside using low frequency waves may be used. Effects of the Invention As described above, according to the present invention, a plurality of thin film materials having different vapor pressures stored in a crucible can be heated. Since it is possible to prevent a film having a different composition ratio from that of the molten metal that has evaporated from the crucible and adhered to the surface of the crucible from penetrating into the molten metal, the composition ratio of the formed thin film can be kept constant.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a vacuum evaporation apparatus according to an embodiment of the present invention, Fig. 2 is an enlarged sectional view of the main part of Fig. 1, and Fig. 3 is a composition ratio and formation of molten metal in a crucible in conventional vacuum evaporation. Changes in the composition ratio of thin films over time? FIG. 4 is a sectional view showing the front structure around the crucible of the conventional example, and FIG. 5 is an enlarged sectional view of the main part for explaining the problems of the conventional example. 1... Thin film material, 2... Crucible, 6.
... Membrane, 6 ... Coil, 7 ... High frequency power supply, 8 ... Base, 9 ... Thin film,
11... Vacuum container. Name of agent: Patent attorney Shigetaka Awano and 1 other person 1st
Figure 1- Book Houzai total 2- Rutsuha 3- Hearth 4-: 4! Water connection 6-・-Koi λshi 7-゛Takama Kumiden Oki, 8 Base 9-Membrane to-・-Basic Hayabusa Nelta/l-Vacuum 2 Volume 12-Shield Diagram QF Castle

Claims (2)

[Claims] (1) A crucible made of an insulator that stores a plurality of thin film materials having different vapor pressures, and a substrate to which a thin film is formed by adhering the vapor of the thin film materials are placed in a vacuum container. a first heating means for heating a thin film material in a crucible, and a thin film formed by vapor generated from the thin film material heated by the first heating means and attached to the surface of the crucible to be heated and reevaporated. A vacuum evaporation device equipped with high-frequency heating means. (2) The vacuum evaporation apparatus according to claim 1, wherein the first heating means is constituted by high-frequency heating means having a frequency lower than that of the high-frequency heating means for heating the thin film formed by the vapor adhering to the surface of the crucible.