JPS5848628B2 - How to raise the temperature of an energized heat-generating evaporation source - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for increasing the temperature of an energized heat-generating evaporation source used primarily in a vacuum evaporation apparatus.

In a vacuum evaporation apparatus, an elongated evaporation source made of, for example, a high-melting-point resistance material is placed below a long sheet-shaped material to be deposited that is fed at a predetermined speed, and is perpendicular to the feeding direction of the material to be deposited. The vapor deposition process is performed on the lower surface of the object by evaporating the raw materials sequentially supplied onto the evaporation source using the heat generated by energizing the evaporation source. There is something.

The method of raising the temperature of the evaporation source used in this type of device is, for example, by fixing a holder made of a conductive material on a pair of fixed electrodes, and placing a long and narrow evaporation source between the two holders. The end portion is loosely fitted into an engagement recess provided in a corresponding holder, and the temperature of the evaporation source is increased by applying a voltage between the two electrodes and energizing the evaporation source. Common.

However, simply fitting the ends of the evaporation sources loosely into the engagement recesses of the holders tends to cause poor contact between the holders and the evaporation sources.

Therefore, in the case where a current of 50 OA or more is passed through the evaporation source, a local heat generation phenomenon may occur due to poor contact at the joint between the outer surface of the end of the evaporation source and the inner surface of the engaging recess of the holder. There is a disadvantage that the temperature of the evaporation source cannot be sufficiently raised due to the generation of intense sparks.

Although such inconveniences can be overcome by firmly fixing the ends of the evaporation sources to the respective holders, since elongated evaporation sources change their longitudinal dimensions significantly due to thermal expansion, If such a solution is adopted, there is a problem in that the evaporation source and the holder are likely to be damaged when the temperature rises.

The present invention was made with attention to such circumstances, and
A conductive material is placed near the joint between the outer surface of the end of the evaporation source and the inner surface of the retaining recess of the holder, and the conductive material is heated by the heat locally generated at the joint when electricity is started. An energized heating type evaporation source that eliminates contact failure by melting and flowing into the joint, and allows the temperature of the evaporation source to be raised smoothly without causing damage to the evaporation source or holder. This provides a method for increasing the temperature.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

Square block-shaped holders 3 and 4 made of a conductive material, for example carbon, are arranged on the pair of fixed electrodes 1 and 2, and an energized heat-generating evaporation source 5 is installed between these holders 3 and 4.

The evaporation source 5 can be in the shape of an elongated rectangular block, and has a recessed part 5a on its upper surface for receiving the raw material to be evaporated, for example, granular aluminum, and has a recessed part 5a for receiving the raw material to be evaporated, for example, granular aluminum. It is made of ceramics such as BN composite EC (trade name; manufactured by Denki Kagaku Kogyo Co., Ltd.).

Both ends thereof are loosely fitted into engagement recesses 3a and 4a provided on the upper surface of each of the holders 3 and 4.

Engagement recesses 3a, 4 between the ends of the evaporation source 5 and the holders 3, 4
The degree of loose fitting with a is as shown in FIG. 2, for example.

That is, when the length of the evaporation source 5 is 10 O ram, the width W is 21 plates, and the thickness t is 10 mrn, the evaporation source 5
and the engagement recess 3a of the holder 3, 4,
0.5 to 0.5 to the inner surface of 4a. It is set so that a gap a of about 0'5 mm is maintained.

Then, the outer surface of the end of the evaporation source 5 and the holders 3 and 4 are connected to each other.
The vicinity of the joint 9 with the inner surface of the engagement recess 3 a v 4a, for example, the intersection 6 between the end face of the evaporation source 5 and the inner bottom surface of the engagement recess 3a, 4a, or the upper surface of the evaporation source 5 and the engagement A conductive material 8 is placed at the intersection 7 with the inner surface of the recesses 3a, 4a, etc.
... will be installed.

Various metals can be used as the conductive substance 8. For example, granular aluminum or the like supplied as a raw material into the concave portion 5a of the evaporation source 5 may be used.

Next, a voltage is applied between the fixed electrodes 1 and 2 to start energizing the evaporation source 5, and the outer surface of the end of the evaporation source 5 is aligned with the inner surface of the engaging recesses 3a and 4a of the holders 3 and 4. The conductive substance 8 is melted by the heat locally generated at the seam 9 and flows into the seam 9, and then electricity is continued to be applied to the evaporation source 5 to raise the temperature of the evaporation source 5 to 14.
00°C to 1500°C.

According to this method, electricity is started to be applied to the evaporation source 5, and local heat generation due to poor contact occurs at the joint between the outer surface of the end of the evaporation source 5 and the inner surface of the engaging recesses 3a and 4a of the holders 3 and 4. Even if this occurs, the conductive substance 8 disposed near the seam 9 melts at that moment and flows between the seams 9, eliminating poor contact at the seam 9.

Therefore, the temperature of the evaporation source 5 can be raised smoothly without generating intense sparks or the like.

Moreover, the ends of the evaporation source 5 are connected to the holders 3 and 4 as before.
Since it is only necessary to loosely fit the evaporation source 5 into the engagement recesses 3a and 4a, it may be difficult to attach the evaporation source 5 to the holders 3 and 4, and the evaporation source 5 and holders 3 and 4 may be damaged when the temperature rises. Of course, no inconvenience will occur.

In the above embodiment, the case where both ends of the evaporation source were loosely fitted into the engagement recesses of the corresponding holders was explained.
The present invention is not limited to such a case, and for example, one end of the evaporation source may be loosely fitted into the engagement recess of the corresponding holder, and the other end may be firmly fixed to the corresponding holder to prevent contact failure. It can be similarly applied to other cases.

As described above, in the present invention, a conductive material is disposed near the seam between the outer surface of the end of the evaporation source and the inner surface of the engagement recess of the holder, and a conductive material is placed in the vicinity of the joint between the outer surface of the end of the evaporation source and the inner surface of the engaging recess of the holder, and when electricity starts flowing, the conductive material is locally formed at the seam. Since the conductive substance is melted by the heat generated and flows into the joint, poor contact between the evaporation source and the holder is eliminated without fixing the end of the evaporation source to the holder. Thus, it is possible to provide a method for raising the temperature of an energized heating type evaporation source, which can smoothly raise the temperature of the evaporation source without causing damage to the evaporation source or the holder.

[Brief explanation of drawings]

The drawings show an embodiment of the invention, with FIG. 1 being a perspective view, FIG. 2 being a front view, and FIG. 3 being a side view. 1, 2... Fixed electrode, 3, 4... Holder 3a, 4a... Engaging recess, 5...
Evaporation source, 8... Conductive substance, 9... Joint portion.

Claims (1)

[Claims] 1. A holder made of a conductive material is disposed on a pair of fixed electrodes, and an evaporation source is installed between these holders by loosely fitting at least one end of the evaporation source into an engagement recess provided in a corresponding holder. In a method for increasing the temperature of an energized heating type evaporation source, in which the temperature of the evaporation source is increased by applying a voltage between both electrodes and energizing the evaporation source, A conductive substance is disposed near the joint with the inner surface of the mating recess, and the conductive substance is melted by heat generated locally at the joint when electricity starts to flow into the joint. A method for increasing the temperature of an energized heating type evaporation source, characterized in that: