JPH0735568B2 - How to use thin film forming equipment - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of using a thin film forming apparatus used in a manufacturing process of semiconductors and the like.

Usually, in order to perform vapor deposition, a vacuum container 1 as shown in FIG.
The inside of the chamber is evacuated to a predetermined vacuum pressure, the crucible 3 containing the thin film forming material 2 and the sample 5 placed on the sample holding member 4 are opposed to each other, and the thin film forming material 4 is heated by applying an electron beam. Then, the thin film forming material 2 is evaporated to form a thin film on the sample 5. The shutter 6 is used to scatter the thin film forming material 2 from the crucible 3 and to prevent the thin film forming material 2 from scattering and preventing the thin film forming material 2 from adhering to the sample 5 until the deposition rate becomes stable and at the end of the deposition. is there. Here, as the material for the vacuum device, a metal having a high mechanical strength, which is less likely to be rusted, and has a small amount of gas released is used. Specific examples of these metals include stainless steel, Fe plated with Cr, and Cu plated with Cr.

Problems to be Solved by the Invention Conventionally, such a material has been used as a structural material for a vacuum device in a shutter as shown in FIG. 5 or a sample holding member. However, when such a material is used, the structure other than the sample, that is, the film adhered to the surface of the structure such as the shutter and the sample holding member has a weak structure because the surface of the structure has a weak adhesive force and is continuously vapor-deposited. There was a problem that peeling occurred at the interface between the surface of the structure and the film and dropped on the lower surface of the vacuum container to contaminate the inside of the vacuum container. There is a problem that a film piece that is peeled off and dropped on the lower surface of the vacuum container rises up during evacuation and leak and adheres to the thin film formation surface of the sample to cause a defect in the deposited film. For example, in the case of an optical disc, the track pitch is 1.5 to 3 μm and the groove width is 0.7 to 1 on the surface on which the recording film is formed.
Tens of thousands of pre-groups with μm and depth of 500-800Å are formed spirally or concentrically. A recording film is vapor-deposited to a desired thickness on the surface on which such a pregroup is formed, and recording is performed by irradiating the recording film with laser light modulated by the recording information to about 1 μm by a condenser lens to form a pit. Alternatively, the recording film is changed in phase. The reproduction is performed by irradiating the recording section with a laser beam and reading the amount of reflected light from the recording section and converting it into an electric signal. However, 1 μm on the pre-group surface and recording film
If a certain amount of foreign matter is attached, sufficient recording cannot be performed on that portion, and the reproduction signal output is small or becomes noise, which affects recording and reproduction. Further, when the adhered foreign matter is large, it affects over a plurality of tracks and the error rate increases. Therefore, it has been a major problem to prevent the peeling of the film from the structure in the vacuum container.

Therefore, the present invention is intended to solve the above problems, and a method of using a thin film forming apparatus for preventing a film attached to a structure inside a vacuum container from peeling off and obtaining a good thin film without defects. The purpose is to provide.

Therefore, in the present invention, the surface of the structure in the vacuum container facing the vapor deposition source is sandblasted to form a rough surface. Then, after adhering the particulate thin film forming material to the sample in the vacuum container, the rough surface thin film forming material adhering portion is again sandblasted to remove the thin film forming material and roughen the structure surface again. It is designed to be used repeatedly.

Function The present invention is to prevent the peeling by forming a rough surface on the surface facing the vapor deposition source by sandblasting, and by adhering the thin film forming material to the rough surface, the adhesive force of the film is dramatically improved. is there. Further, it can be reused by removing the thin film forming material attached to the rough surface.

Embodiments Embodiments of the present invention will be described below with reference to the drawings. The same components as those in FIG. 5 are designated by the same reference numerals and the description thereof will be omitted.
In FIG. 1, reference numerals 8, 9 and 10 designate a shutter 6 which is an internal structure of a vacuum container, a sample holding member 4 and a rough surface formed by sandblasting on a surface side of a deposition preventing plate 8 which faces a crucible 3 which is a vapor deposition source. The surface. Here, the sand blasting method is a method in which high hardness particles are jetted together with a high gas at a high speed from a nozzle onto the surface of a workpiece, and collide with the surface to roughen the surface. Therefore, the state of the processed surface changes depending on the shape of the particles used. Therefore, when the particle shape is round, the surface roughness is accompanied by small undulations, as shown in Fig. 2. When polygonal and complicated particles are used, the surface condition is complicated as shown in Fig. 3. It will have a unique shape. The adhesion strength of the film depends on the condition of the adhesion surface, and when the adhesion surface is as shown in FIG. 2, the surface condition is spherical but the surface condition is spherical even if the surface roughness is rough. They are connected and the surface condition of the spherical surface is relatively smooth, and the adhesion strength does not improve even if the thin film forming material adheres to such a surface. However, if the surface roughness is processed into a complicated shape as shown in FIG. 3, the adhesion strength of the film is dramatically improved. The shape of the rough surface formed on the shutter 6, the sample holding member 4, and the deposition preventive plate 7 shown in FIG. 1 is as shown in FIG. The shutter 6, the sample holding member 4, and the deposition-inhibiting plate 7 were variously changed in surface roughness, and an experiment was carried out to determine the number of sheets to be peeled off by continuous vapor deposition so that the deposition amount of one film was 1500 Å. The results obtained are shown in FIG. From FIG. 4, when comparing the same surface roughness, for example, Rmax of 5 μm to 20 μm, the sandblasted surface-roughened material can deposit several times more than the milled surface-roughened material. However, if a structure whose surface roughness is roughened by sandblasting is used, the number of vapor deposition increases. However, if the roughness is increased, the processing stress will be extremely large and a large warp will occur when the plate thickness is thin, but it is usually 1 m which is commonly used.
When the thickness is about m, a roughness of 60 μm or less can be used with almost no warpage. It should be noted that FIG. 4 shows data for the shutter closest to the vapor deposition source and having the largest deposition amount of the vapor deposition film. Therefore, the number of vapor-deposited sheets increases more than the data of FIG. 4 in the portion far from the shutter.
In addition, after continuously vapor-depositing the structure having the roughness as described above by the sandblasting method to finish the vapor deposition of the desired number, the film deposited on the surface of the surface roughened portion of the structure is re-deposited. By sandblasting, the deposited film can be removed and the surface can be roughened at the same time, so that the same structure can be repeatedly used and the economical efficiency is improved.
Up to now, the explanation has been given by forming the rough surface only on the side facing the vapor deposition source, but if the rough surface as described above is formed on both sides, the back side like the CVD method sputtering method, the ion plating method, etc. It is also effective for a thin-film forming apparatus in which a thin-film forming material wraps around and adheres.

EFFECTS OF THE INVENTION According to the present invention, it is possible to dramatically reduce film peeling from the structure surface by performing surface roughening processing on the surface of the structure facing the vapor deposition source in the vacuum container by the sand blasting method, and it is possible to reduce defects. -Free film can be created and quality yield is improved.
If the film deposited on the roughened surface is sandblasted again, the film can be removed and the surface can be roughened at the same time, so that the structure can be repeatedly used and the economical efficiency can be remarkably improved. it can.

[Brief description of drawings]

FIG. 1 is a sectional front view showing a schematic structure of a thin film forming apparatus according to an embodiment of the present invention, and FIGS. 2 and 3 are cross-sectional views showing a surface condition formed on a structure surface of the apparatus by a sandblasting method. FIG. 4 is a characteristic diagram showing the relationship between surface roughness and the number of peeled sheets by the same apparatus, and FIG. 5 is a sectional front view showing a schematic configuration of a thin film forming apparatus in a conventional example. 1 ... Vacuum container, 2 ... Thin film forming material, 3 ... Crucible,
4 ... sample holding member, 5 ... sample, 6 ... shutter,
7: Anti-adhesive plate, 8, 9, 10: Rough surface.

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Eizo Kubo 1006 Kadoma, Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Politics Kinoshita 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. 72) Inventor Kunio Tanaka 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) Reference JP-A-62-112778 (JP, A)

Claims (1)

[Claims] 1. A thin film forming apparatus in which the surface of a structure inside a vacuum container is roughened by sandblasting, a thin film is formed on a substrate of a sample inside the vacuum container by a gas phase method, and then the structure is re-formed. A method of using a thin film forming apparatus, which comprises sandblasting to remove the sample attached to the structure and roughening the surface of the structure again for repeated use.