JPS62142758A - Apparatus for forming thin film and method for using same - Google Patents

Abstract

PURPOSE:To efficiently form a thin film having no defects on a sample by vapor deposition in a vacuum vessel by roughening the surface of the internal structure of the vessel confronting a vapor depositing source so as to reduce the stripping of a film from the inner surface of the vessel. CONSTITUTION:The surface of the internal structure 7 of a vacuum vessel 1 is roughened 10 by sandblast. Fine particles of a thin film forming material 2 are deposited on a sample 5 in the vessel 1. Then the particles of the material 2 deposited on the structure 7 are removed by sandblasting and the surface of the structure 7 is roughened again.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a thin film forming apparatus used in the JJJ fabrication process of semiconductors, etc., and a method of using the same.

2. Description of the Related Art Usually, in order to carry out vapor deposition, a vacuum vessel 1 is used as shown in FIG.
The inside of the 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 made to face each other, and the thin film forming material 4 is irradiated with an electron beam to heat it. The thin film forming material 2 is evaporated to form a thin film on the sample 5. Note that the shutter 6 scatters the thin film forming material 2 from the crucible 3 until the vapor deposition rate is stabilized, and also at the end of the vapor deposition to prevent the scattering of the thin film forming material 2 from the sample 6.
It is used to prevent adhesion to the surface.

As a material for vacuum equipment, it has strong mechanical strength and is resistant to rust and releases gas! Metals with less 1F are used. Specifically, these metals include stainless steel, F
There are those with Cr plating on θ, and those with CuKCr plating.

Conventionally, such materials have been used as a fig structure (as shown in Fig. However, when such coating materials are used, they may adhere to the surfaces of structures other than the sample, such as shutters, sample holding parts, etc., because the surfaces of the structures are smooth. When continuous evaporation is performed with weak adhesion, there is a problem that peeling occurs at the interface between the structure surface and the film, falling to the bottom of the vacuum container and contaminating the inside of the vacuum container. There was a problem that film fragments that fell on the bottom surface would fly up during exhaust or leakage, and adhere to the thin film formation surface of the sample, causing defects in the deposition process.For example, in the case of optical discs, the recording film formation surface has a track pitch. 1.6-3μm, groove width 0.7-1μm, depth SOO
Tens of thousands of pre-groups of ~5ooAa degree are formed in a spiral or concentric shape.

A recording film is deposited to a desired thickness on the surface on which such pregroups are formed, and for recording, pits are formed by irradiating the recording film with a laser beam modulated by the recorded information and condensing it to about 1 μm using a condensing lens. Alternatively, the recording film may be subjected to a phase change. Reproduction is performed by irradiating a recording section with a laser beam, reading the amount of light reflected from the recording section, and converting it into an electrical signal. However, if foreign matter of about 1 μm adheres to the pregroup surface and recording film, the j(1
Therefore, sufficient recording is not possible, and the reproduced signal output is also small or produces noise, which has a negative impact on recording and reproduction. Furthermore, if the attached foreign matter is large, it will affect multiple tracks and increase the error rate. Therefore, it has been a major issue to prevent the membrane from peeling off from the structures inside the vacuum container.

SUMMARY OF THE INVENTION The present invention aims to solve the above-mentioned problems, and provides a thin film forming apparatus and its use that prevents the film attached to the structure inside the vacuum container from peeling off and falling, thereby producing a good thin film without any defects. The purpose is to provide a method.

Means for Solving the Problems According to the present invention, the surface of the structure inside the vacuum container facing the vapor deposition source is subjected to sandblasting to form a rough surface. After adhering fine particulate thin film-forming material to the sample in the vacuum container, the thin film-forming feed was attached to the rough surface 7”
The structure was sandblasted again to remove the thin film forming material and to roughen the surface of the structure again so that it could be used repeatedly.

Function The present invention forms a rough surface by sandblasting on the surface facing the vapor deposition source, and attaches a thin film forming material to this rough surface, thereby dramatically improving the adhesion of the film and preventing peeling. be. Moreover, it can be used again by removing the thin film forming material attached to the rough surface.

Example Embodiments of the present invention will be described below with reference to the drawings.

Components that are the same as those in FIG. 5 are given the same numbers, and explanations thereof will be omitted. In Fig. 1, 8, 9, 10 are 'l: internal structure of Js empty container, 7 holder 6, sample holding part 4.
．． - This is a set part formed by sandblasting on the side of the deposition prevention plate 8 that faces the crucible 3, which is the evaporation source. 3. Sandblasting is a method in which particles with high hardness are injected together with a high gas at high speed onto the surface of the workpiece through a nozzle and collided with each other to roughen the surface. Therefore, the state of the processed surface changes depending on the shape of the particles used. Therefore, if the shape of the particle is round, the surface roughness will have small undulations as shown in Figure 2, and if particles with a complex polygonal shape are used, the surface condition will be complicated as shown in Figure 3. It has a shape. The adhesion strength of the film is influenced by the condition of the adhesion surface.If the adhesion surface is as shown in Figure 2, the surface roughness may be rough, but if you look closely, the surface condition will be continuously spherical. The surface condition of the spherical portion is relatively smooth, and even if the thin film forming material adheres to such a surface, the +j adhesion strength will not improve. However, if the film is processed to have a complex shape and roughness as shown in FIG. 3, the adhesion strength of the film can be dramatically improved. /sector 6. shown in FIG. Sample holding member 4. The shape of the rough surface formed on the anti-Xj plate 7 is as shown in FIG. Here/Yanotar6. Sample holding section 4. Fig. 4 shows the results of an experiment in which the thickness of the plate 7 was varied and the amount of film deposited at one time was 15001, and the amount of film deposited was continuously deposited to determine how many sheets would cause peeling. .

From Figure 4, the same surface roughness, for example, Rmax 5 μm ~ 20
When comparing the surface roughness in μm, the surface roughened by sandblasting can deposit several times more than the surface roughened by milling. However, if a structure whose surface roughness is roughened by sandblasting is used, the number of deposited layers will increase. If the surface roughness is made coarser, the processing stress becomes extremely severe and large warpage will occur if the plate thickness is thin, but if the surface roughness is set to less than 60μm in the case of a thickness of about 1H, which is commonly used, it will hardly occur. Can be used without warping. Note that FIG. 4 shows data at /Yatta, which is closest to the vapor deposition source and has the largest amount of deposited film. Therefore, in areas farther away from the shutter, the number of deposited sheets increases more than the data in FIG. 4 shows. In addition, after the desired number of layers have been deposited by continuous vapor deposition using a structure processed by sandblasting to the roughness described above, the film deposited on the surface of the roughened part of the structure is re-evaporated. Sandblasting can remove the deposited film and at the same time roughen it, making it possible to use the same structure repeatedly and improving economic efficiency. So far, we have explained the case where a rough surface is formed only on the side facing the evaporation source, but if the above-mentioned rough surface is formed on both sides, the back side can be It is also effective for thin film forming apparatuses in which the thin film forming material goes around and adheres to the surface.

Effects of the Invention According to the present invention, by roughening the surface of the structure in the vacuum container facing the evaporation source using a sandblasting process, peeling of the film from the surface of the structure can be dramatically reduced, and defects can be reduced. It is possible to create a film free of blemishes, improving quality yield.

Furthermore, 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, making it possible to use the structure repeatedly and significantly improving economic efficiency. can.

[Brief explanation of drawings]

FIG. 1 is a sectional front view showing a schematic configuration of a thin film forming apparatus according to an embodiment of the present invention, and FIGS. 2 and 3 are sectional views showing the surface state formed by sandblasting on the surface of a structure of the same apparatus. , FIG. 4 is a characteristic diagram showing the relationship between surface roughness and the number of sheets peeled off using the same apparatus, and FIG. 6 is a sectional front view showing a schematic configuration of a conventional thin film forming apparatus. 1... Vacuum container, 2... Thin film forming material, 3... Crucible, 4... Sample holding member, 5... Sample, 6.../Yanotar, 7
・・・・・・Adhesion prevention plate, 8. 9. 10...Rough surface. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure night 27 Kaigu=:Z; 3rd figure-2===

Claims (3)

[Claims] (1) A thin film forming apparatus characterized in that a rough surface is formed by sandblasting on a surface of a structure constructed inside a vacuum container that faces an evaporation source. (2) The roughness of the rough surface formed by sandblasting is Rm
The thin film forming apparatus according to claim 1, wherein the thin film is formed to have an ax of 5 μm or more. (3) After roughening the surface of the structure inside the vacuum container by sandblasting and attaching fine particulate thin film forming material to the sample inside the vacuum container, the rough surface to which the thin film forming material is attached is again sandblasted. A method for using a thin film forming apparatus, characterized in that the thin film forming material is removed and the surface of the structure is roughened again for repeated use.