JPH10110260A - Filament for vacuum deposition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain uniformization and high efficiency of evaporation of an evaporating source by providing the space between the place in which the temp. of the filament to be used for a resistance heating type vacuum depositing machine is made highest and the feeding point from an electrode. SOLUTION: At the time of forming the wire rod or sheet material of tungsten or the like into a prescribed filament 1 by using a press die or the like, a vacuum deposing source mounting part 2 is simultaneously formed. At this time, the position of the vacuum depositing source mounting part 2 is set to the space between the part in which the temp. of the filament in the process of heating is made highest and the feeding point from an electrode. Experientially, this part preferably lies at the position satisfying L1-10>=L>=75W, where, in the inequality, L(mm) denotes the horizontal distance between the center of the filament and the center of the vacuum depositing source mounting part, L1(mm) denotes the horizontal distance between the center of the filament and the feeding point, and W(g) denotes the weight of the vacuum depositing source. Furthermore, as for the shape of the vacuum depositing source mounting part 2, the vertical cross-section is approximately formed of U-shape from the convenience in the production.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a filament of a resistance heating type vapor deposition machine. In particular, the present invention relates to a structure or a shape of a filament for efficiently and uniformly evaporating an evaporation source.

[0002]

2. Description of the Related Art Conventionally, a disk substrate to be a front surface and a rear surface is formed by injection molding of acrylic resin or the like, and fine irregularities of a stamper provided on a die in advance are transferred to the surface of each disk substrate. A method of manufacturing a video disk is known in which a signal portion is formed by vapor-depositing an aluminum reflective film on irregularities, a protective coat film is further formed on the signal portion, and the disk substrates are bonded together with an adhesive. In this case, aluminum as an evaporation source is mounted on the filament of the resistance heating type evaporation machine, and the melting timing and evaporation rate of the evaporation source are adjusted by Joule heat generated by supplying power to the filament.

However, the temperature distribution on the filament is
The temperature changes depending on the balance of Joule heat and radiant heat.However, heat loss occurs due to heat transfer to the electrode near the feeding point to the filament, so the temperature decreases, and the temperature near the center of the filament tends to be the highest. Generally. Therefore, the timing of melting and the state of deployment to the filament after melting change depending on the attachment site of the evaporation source. For example, when a vapor deposition source was attached to the center of the filament at the highest temperature, a phenomenon was often observed in which the vapor deposition source dropped from the filament simultaneously with melting. On the other hand, when it is mounted near the power supply point at the lowest temperature, the evaporation source does not completely melt, and the evaporation is usually insufficient.

The temperature distribution on the filament is determined by the shape of the filament and the shape of the electrode when the supplied current is constant.
That is, the region where melting occurs in a timely manner and can be smoothly developed into the filament is in a very limited range. In other words, in vapor deposition, it is important to sufficiently manage the mounting site of the vapor deposition source. However, the conventional manual mounting of the vapor deposition source has poor work accuracy, and a positional shift occurs due to mechanical vibration or the like before the start of vapor deposition, and the vapor deposition source deviates from a desired mounting portion, so that the vapor deposition process becomes unstable. The above-mentioned trouble often occurred.

[0005]

That is, conventionally, the vapor deposition source is easily mounted on the optimum mounting portion of the vapor deposition source determined from the temperature distribution on the filament, and the position of the vapor deposition source on the filament due to mechanical vibration or the like. There was no shift, and there was no means for preventing the deposition trouble caused by this.

[0006]

The inventor of the present invention has made it possible to keep the position of the vapor deposition source mounted on the filament constant by making the vapor deposition site or shape of the filament appropriate, and to achieve a stable vapor deposition at all times. I found what can be done.

That is, the present invention provides a filament used in a resistance heating type vapor deposition machine, wherein a vapor deposition source mounting portion is provided between a portion where the temperature during heating is the highest and a feeding point from the electrode. The shape of the deposition source mounting portion is that the vertical cross section is substantially U-shaped.

[0008]

Embodiments of the present invention will be described below with reference to the accompanying drawings. That is, FIG.
(B) and (c) are conceptual longitudinal sectional views of the vapor deposition filament of the present invention.

In each of the embodiments shown in FIG. 1, the filament (1) is formed by molding a wire or a plate-like material such as tungsten into a predetermined shape using a press die or the like. At this time, a deposition source mounting portion (2) having a shape as shown in the figure is formed at the same time. 0.5 to 1.5 mm in diameter as wire
May be used as such, or a stranded wire obtained by twisting several of them.

In the present invention, the position of the deposition source mounting portion (2) provided on the filament needs to be between the portion where the temperature during heating becomes the highest and the feeding point from the electrode. Usually, the feeding point from the electrode is often at both ends of the filament, and in such a case, the portion where the temperature during heating is highest is often the center of the filament (1). In accordance with the heating time schedule, the actual mounting site (2) can be positioned not only to reach the melting temperature within a predetermined time, but also to a position where the molten deposition source does not drop from the filament before fully developing on the filament. Set.

Empirically, it is preferable that the above-mentioned deposition source mounting portion is located at a position satisfying the following expression. L1-10 ≧ L ≧ 75W where L (mm) is the horizontal distance between the center of the filament and the center of the deposition source mounting site, and L1 (mm) is the distance between the center of the filament and the feeding point. The horizontal distance is W (g)
Represents the weight of the evaporation source. Here, the center of the filament is between the left and right power supply points existing on the filament (for example, when a wide bus bar is used for power supply, it means the innermost point of each of the contact portions with the bus bar). Means the intermediate point on the horizontal distance. The center of the deposition source mounting portion refers to an intermediate point on the horizontal distance between both end positions when the mounting portion has a width. When there are a plurality of deposition source mounting portions, it is important that each of the mounting portions satisfies the above expression.

Also, in the present invention, the shape of the deposition source mounting portion (2) is not particularly limited as long as the mounted deposition source does not shift due to mechanical vibration, but considering the convenience in manufacturing. It is preferable that the vertical cross section be substantially U-shaped. The size is related to the size of the deposition source to be mounted here, and not only can the deposition source be suspended or placed on the mounting site, but also stay at the mounting site even if the position is slightly shifted due to mechanical vibration. It is important that you can afford it. Of course, if necessary, the mounting portion (2) can be formed in a boat shape to prevent the evaporation source from escaping.

[0013]

The present invention will be described in more detail with reference to the following Examples and Comparative Examples, but the present invention is not limited to only the following Examples.

Example 1 A filament (1) shown in FIG. 1A was obtained by press-forming three twisted tungsten wires each having a diameter of 1 mm. The distance between the left and right ends of the filament (1) is 140 mm,
The depth of the two U-shaped deposition source mounting portions (2) (the depth from the highest position in the center to the bottom of the U-shape) was 20 mm, and the distance between the two U-shaped bottoms was 70 mm. The feeding point is located at a position 60 mm in horizontal distance from the center of the filament. One or both of the deposition source mounting portions (2) has a width of 12 mm, a length of 12 mm, a thickness of 500 μm, and a weight of 0.2.
0 g of an aluminum ribbon was folded in two in the longitudinal direction, suspended, and used as an evaporation source.

Example 2 A filament (1) shown in FIG. 2B was obtained by press-forming three twisted tungsten wires each having a diameter of 1 mm. The distance between the left and right ends of the filament (1) is 140 mm, the depth of the left U-shaped deposition source mounting portion (2) (the depth from the position of the horizontal portion to the bottom of the U-shape) is 5 mm, and the bottom of the U-shape The horizontal distance between the filament and the center of the filament was 20 mm. The feeding point is located at a position 50 mm in horizontal distance from the center of the filament, and this deposition source mounting portion (2) has a width of 10 mm and a length of 10 m.
m, thickness 500μm, weight 0.14g aluminum
The ribbon was folded in two in the longitudinal direction and suspended, and used as a vapor deposition source.

Example 3 The filament (1) shown in FIG. 3C was obtained by press-forming three twisted tungsten wires each having a diameter of 1 mm. The distance between the left and right ends of the filament (1) is 140 mm, the depth of the left U-shaped deposition source mounting portion (2) (the depth from the position of the horizontal portion to the bottom of the U shape) is 10 mm, and the bottom of the U shape The horizontal distance between the filament and the center of the filament was 50 mm. The feeding point is located at a position of 65 mm in horizontal distance from the center of the filament, and this deposition source mounting portion (2) has a width of 12 mm and a length of 12 m.
m, thickness 500μm, weight 0.20g aluminum
The ribbon was folded in two in the longitudinal direction and suspended, and used as a vapor deposition source.

[Comparative Examples 1-2] In Example 2, the horizontal distance between the bottom of the U-shape and the center of the filament was 20 mm, except that they were 8 mm and 42 mm, respectively. Similarly, Comparative Examples 1 and 2
And

Both ends of the filament exemplified in FIGS. 1 (a) to 1 (c) were fixed to electrodes, a vapor deposition source was mounted, power was supplied and heated to melt and evaporate, and vacuum deposition was performed on an acrylic resin disk substrate. . In Examples 1 to 3, there was no displacement of the deposition source, and the occurrence of deposition failure was significantly reduced as compared with the case where a conventional linear filament was used. However, Comparative Example 1
In, the displacement of the deposition source did not occur, but the aluminum ribbon dropped at the same time as the melting, resulting in poor deposition. In Comparative Example 2, although the displacement of the deposition source did not occur, the aluminum ribbon did not melt and the deposition could not be performed.

The filament shapes and the values of L1, L and W in each of the examples and comparative examples are as follows. Filament L1 LW Shape (mm) (mm) (g) -------------------------------------------------------------------------- Example 1 FIG. 1 (a) 60 35 0.20 Example 2 FIG. 1 (b) 50 20 0.14 Example 3 FIG. 1 (c) 65 50 0.20 Comparative Example 1 FIG. 1 (b) 50 8 0.14 Comparative Example 2 FIG. (B) 50 42 0.14

[0020]

According to the present invention, by providing the deposition source mounting portion at an appropriate position, the deposition source can be easily mounted on the optimum mounting portion of the deposition source determined from the temperature distribution on the filament, and the mechanical vibration There is no displacement of the vapor deposition source on the filament due to the above-mentioned factors, and vapor deposition trouble due to this can be prevented. Further, by making the shape of the deposition source mounting portion substantially U-shaped, the production is easy and the above effects can be further ensured.

[Brief description of the drawings]

FIG. 1 is a conceptual longitudinal sectional view of a vapor deposition filament of the present invention.

[Explanation of symbols]

1 Filament 2 Deposition source mounting site L Horizontal distance between center of filament and center of deposition source mounting site L1 Horizontal distance between center of filament and feeding point

Claims (3)

[Claims] 1. A filament used in a resistance heating type vapor deposition machine, wherein a vapor deposition source mounting portion is provided between a portion where the temperature during heating is the highest and a feeding point from an electrode. Filament for vapor deposition. 2. The filament for vapor deposition according to claim 1, wherein the deposition source mounting portion is located at a position satisfying the following expression. L1-10 ≧ L ≧ 75W where L (mm) is the horizontal distance between the center of the filament and the center of the deposition source mounting site, and L1 (mm) is the distance between the center of the filament and the feeding point. The horizontal distance is W (g)
Represents the weight of the evaporation source. 3. The shape of the deposition source mounting portion is such that its vertical cross section is substantially U-shaped.
The filament for vapor deposition according to claim 1 or 2, wherein the filament has a character shape.