JPH11264069A - Side heating type evaporating source fur vacuum deposition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a side heating type evaporating source for vacuum deposition excellent in impact resistance. SOLUTION: In a crucible 12 for melting a metal, a temp. at the part made larger is lowered as compared to the other part 14 and a temp. difference with the supplied metal material is lowered since a thickness of a part 13 at a bottom part to which a metal material for vapor deposition is supplied is made larger than that at the other part 14, when the crucible is heated uniformly from downward of the crucible 12 by the side heating type heater 11. In this way, a generation of crack by thermal shock is prevented and a use life of the crucible 12 is extended.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an indirectly heated evaporation source for vacuum evaporation for heating and evaporating a metal material.

[0002]

2. Description of the Related Art Conventionally, aluminum,
As an apparatus for performing vacuum deposition of metals such as copper, silver, and zinc,
A roll-up type vapor deposition apparatus as shown in FIG. 7 is used. This apparatus is provided with a cooling roller 2 for feeding the film 4 while cooling it, opposite to the evaporation source 1 for evaporating the metal material for vapor deposition. On the peripheral surface of the cooling roller 2 at the same speed as the cooling roller 2,
The film 4 is coated with metal evaporated from the evaporation source 1 while being cooled in close contact with the cooling roller 2, and is wound by a winding roller 5. An expanding roller 6 is provided between the unwinding roller 3 and the cooling roller 2, and an expanding roller 7 is also provided between the winding roller 5 and the cooling roller 2. Reference numerals 6 and 7 are configured such that the peripheral speed can be varied.
Although not shown, when the evaporation source 1 is an electron beam heating system or a resistance heating system, a material supply mechanism for automatically supplying a metal material for evaporation reduced by evaporation is provided.

The present applicant has proposed an indirectly heated evaporation source as an evaporation source capable of performing vacuum deposition for a long time and many times using this apparatus (Japanese Patent Application Laid-Open No. H8-311638). FIG. 4 shows the whole of the indirectly heated evaporation source 1, FIG. 5 shows a plan view of the metal melting crucible 31, and FIG. 6 shows a sectional view of the metal melting crucible 31. The evaporation source 1 is made of a refractory metal such as carbon or tungsten and has a boat-shaped indirectly heated heater 21 having a substantially rectangular recess, and an insulator ceramic such as aluminum nitride, and a substantially rectangular cavity 23. And a metal melting crucible 31 having a boat shape. And the crucible 31
The bottom surface is incorporated into the indirectly heated heater 21 such that the bottom surface contacts the upper surface of the recess of the indirectly heated heater 21. And
An electric current is applied to the indirectly heated heater 21 to indirectly heat the crucible 31 from the bottom and side surfaces, so that the evaporation material supplied into the crucible 31 is melted and evaporated. In addition,
The dimensions of the crucible 31 are 32 mm wide and 156 m long.
m, the height is 10 mm, and the size of the cavity 23 is 26 mm in width, 95 mm in length, and 5 mm in depth.

In the conventional vacuum deposition conditions, when the film thickness to be formed is about 400.degree., The running speed of the film 4 is about 300 m / min, but at present, from the viewpoint of improving production efficiency. High-speed film formation with a running speed of the film 4 of 600 to 1000 m / min has been required. Under the condition of the high-speed film formation, a vapor deposition with a film thickness of 400 ° like the conventional case naturally requires a larger evaporation amount, that is, a higher evaporation rate than the conventional case. Increasing the evaporation rate means that the amount of the molten metal material decreases faster, and the supply rate of the metal material must be correspondingly increased.

When the metal material is supplied to the crucible 31, since the molten metal is supplied to a portion where the molten metal has been evaporated, the temperature of the portion of the crucible 31 to which the metal material is supplied decreases, and the temperature changes. Thermal shock (thermal shock) occurs.

When the metal material for vapor deposition is continuously supplied into the cavity 23 of the crucible 31, since the metal is always melted at the same location, the supply portion is significantly deteriorated due to thermal shock, and the crucible is deteriorated. 31 is a cause of a decrease in life. Here, the thickness of the bottom of the conventional crucible 31 is uniform at all positions, as shown in FIG. Therefore, when the indirectly heated heater 21 uniformly heats the crucible 31 from below, the crucible 3
There is no difference in temperature due to a difference in position in one cavity 23, and the part to which aluminum is supplied is also heated to a high temperature at which molten aluminum is evaporated. Therefore, the temperature difference between the supplied aluminum and the heated portion in the crucible 31 being heated is large, and the temperature is easily affected by the thermal shock. Furthermore,
When considering a crucible that satisfies the demands for high-speed film formation as described above, the crucible is continuously subjected to thermal shock due to the increase in the supply rate of aluminum accompanying high-speed film formation. An excellent crucible is needed.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has as its object to provide an indirectly heated evaporation source for vacuum deposition having excellent thermal shock resistance.

[0008]

SUMMARY OF THE INVENTION The object of the present invention is to provide an indirectly heated heater made of a conductor and a metal melting crucible made of an electrical insulator heated by the indirectly heated heater. In the indirectly heated vacuum evaporation source for vacuum deposition incorporated such that the bottom surface of the indirectly heated heater surface is in contact with the indirectly heated heater surface, the thickness of a portion of the bottom of the crucible to which the metal material for deposition is supplied is thicker than other portions. An indirectly-heated evaporation source for vacuum evaporation characterized by the following.

That is, the metal melting crucible of the present invention comprises:
The thickness of the bottom portion where the metal material for vapor deposition is supplied is made thicker than the other portions, so that when the indirectly heated heater is uniformly heated from below the crucible, the temperature of the thickened portion becomes higher than the other portions. The temperature is lower than that of the portion, and the temperature difference with the supplied metal material can be reduced.

[0010]

Next, embodiments of the present invention will be described with reference to the drawings.

In FIG. 1, reference numeral 10 denotes the entirety of the indirectly heated evaporation source according to the present embodiment, and this evaporation source 10 comprises an indirectly heated heater 11 and a crucible 12 for melting metal. The indirectly heated heater 11 is made of, for example, a conductor such as carbon or a high-melting point metal such as tungsten, and has a boat-like shape provided with depressions so that the bottom and side surfaces of the metal melting crucible 12 can be heated. I have.

FIG. 2 is a plan view of the metal melting crucible 12, and FIG. 3 is a sectional view taken along the line [3]-[3] in FIG. The metal melting crucible 12 is made of an insulator such as aluminum nitride, boron nitride, or a mixture thereof, and has a boat-like shape having a substantially rectangular cavity 16. At one end of the cavity 16, there is provided a material supply section 13 in which aluminum which is a metal material for vapor deposition is supplied and melted. As shown in FIG. Is formed thicker than other portions, that is, the evaporating portion 14 where the molten aluminum evaporates. Further, the upper edge portion of the crucible 12 is integrally formed with a flange portion 15 extending horizontally outward along the upper edge portion.

The size of the crucible 12 including the flange portion 15 is 36.
mm, the length L is 166 mm, the height H is 15 mm, and the inner hole 16 has a width w of 24 mm and a length 1 (lowercase ell) of 1
54 mm, the thickness t of the evaporation unit 14 is 3 mm, and the material supply unit 1
3 has a thickness T of 6.5 mm. The width W ′ of the flange portion 15 is 3 mm, and the thickness H ′ is 3 mm.

Then, the crucible 12 is assembled into the indirectly heated heater 11 such that the bottom surface of the crucible 12 is in contact with the upper surface of the recess formed in the indirectly heated heater 11. At this time, crucible 1
The second flange portion 15 covers the upper surface of the indirectly heated heater 11,
The gap formed between the outer peripheral surface 17 of the crucible 12 and the concave inner peripheral surface of the indirectly heated heater 11 is covered.

The indirectly heated evaporation source 10 according to the present embodiment is configured as described above, and the operation will be described next.

Indirectly heated evaporation source 1 constructed as described above
At 0, an electric current is supplied to the indirectly heated heater 11 to indirectly heat the crucible 12. Then, room temperature aluminum, which is a metal material for vapor deposition, is supplied to the material supply unit 13 of the crucible 12.
To supply. At this time, the material is uniformly heated from the bottom side of the crucible 12 by the indirectly heated heater 11, but the thickness T (6.5 mm) of the material supply unit 13 is equal to the thickness t (3 mm) of the evaporation unit 14. Since it is formed thicker, the heat capacity of the material supply unit 13 is large, and the temperature decrease is small even when a normal temperature aluminum material is supplied. Further, the fact that the thickness is large means that the indirectly heated heater 1
The temperature rise of the material supply unit 13 due to heating from 1 is also slow. Therefore, by the above-mentioned, the thermal shock in the material supply section 13 of the crucible 12 can be reduced, the generation of cracks can be suppressed, and the service life of the crucible 12 can be extended.

The supply of aluminum as a metal material for vapor deposition is performed from above the crucible 12. For example, linear aluminum is continuously supplied into the crucible 12 by a material supply mechanism (not shown). Supply. When this aluminum is supplied, aluminum may come off from the crucible 12 due to radiant heat from the crucible 12 or internal stress remaining in the metal material. In addition, since aluminum has high wettability, there is a possibility that aluminum may go up the inner peripheral wall surface of the cavity 16. When these situations occur, in the conventional evaporation source 1 shown in FIG. 4, since the gap between the crucible 31 and the indirectly heated heater 21 is exposed, there is a possibility that aluminum may enter there.

Therefore, the crucible 12 according to the present embodiment is integrally formed with a flange portion 15 along the upper edge, and the flange portion 15 and the outer peripheral surface 17 of the crucible 12 are indirectly heated. It covers a gap generated between the heater 11 and the inner peripheral surface of the recess. Thus, even if the above-described situation occurs, it is possible to prevent aluminum from entering between the crucible 12 and the indirectly heated heater 11. Accordingly, the intrusion of aluminum causes breakage of the indirectly heated heater 11 due to thermal shock caused by contact between the aluminum and the indirectly heated heater 11 which is energized and has a high temperature. Because of the use of carbon or high melting point metal, the reactivity with aluminum is large, and it is eroded or compounds that are impurities are generated.
That can be prevented. Further, even if the supply of aluminum is shifted, it does not enter between the crucible 12 and the indirectly heated heater 11, so that fine adjustment of the supply mechanism is not required, and the operability is increased. Further, the flange portion 15 also has a function as a shielding plate for shielding radiant heat from the indirectly-heated heater 11 to a film installed and cooled above the evaporation source 10.

Although the embodiments of the present invention have been described above, the present invention is, of course, not limited thereto, and various modifications can be made based on the technical concept of the present invention.

In the above embodiment, aluminum is used as the evaporating material, but other metals such as copper, silver, zinc, etc. may be used instead.

[0021]

As described above, according to the indirectly heated evaporation source for vacuum evaporation of the present invention, the thickness of the portion of the bottom of the metal melting crucible to which the metal material for evaporation is supplied is compared with that of other portions. Thick. As a result, thermal shock in this area during material supply, especially thermal shock that frequently occurs due to an increase in the material supply speed due to high-speed film formation, can be reduced to prevent cracks from occurring, greatly extending the service life of the crucible. Can be extended.

[Brief description of the drawings]

FIG. 1 is a perspective view of an indirectly heated evaporation source according to an embodiment of the present invention.

FIG. 2 is a plan view of a crucible for melting metal according to an embodiment of the present invention.

FIG. 3 is a sectional view taken along line [3]-[3] in FIG.

FIG. 4 is a perspective view of a conventional indirectly heated evaporation source.

FIG. 5 is a plan view of a conventional metal melting crucible.

6 is a sectional view taken along line [6]-[6] in FIG.

FIG. 7 is a schematic view showing a conventional vacuum evaporation apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Indirectly heated evaporation source 11 Indirectly heated heater 12 Crucible for melting metal 13 Material supply part 14 Evaporation part 15 Flange part

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kafumi Ota 523 Yokota, Yamatake-cho, Yamatake-gun, Chiba Pref. Japan Vacuum Technology Co., Ltd.

Claims (2)

[Claims] 1. An indirectly heated heater made of a conductor, and a metal melting crucible made of an electrical insulator heated by the indirectly heated heater, wherein the bottom surface of the crucible is the indirectly heated heater surface. Characterized in that in the indirectly heated evaporation source for vacuum evaporation incorporated so as to be in contact with, the thickness of the portion of the bottom of the crucible to which the metal material for evaporation is supplied is thicker than other portions. Type evaporation source. 2. The method according to claim 1, wherein a flange portion is integrally formed along an upper edge portion of the crucible, and the flange portion is shaped to cover an upper surface of the indirectly heated heater. Indirectly heated evaporation source for vacuum evaporation.