JPS59104475A - Machine for e/b vapor deposition - Google Patents

Abstract

PURPOSE:To hold the thickness of a formed vapor deposition film uniform, while avoiding the complicated exchange of a filament, etc., by scanning electron beams from the titled machine for E/B vapor deposition to heat a thin film material so that atoms are formed from its entire surface. CONSTITUTION:In the beam-forming source of the machine for E/B vapor deposition, electron beams of high density outputted from a filament 11 connected to a filament power source 10 is accelerated between the filament 11 and a crucible 14 by a power source 9 for accelerating voltage, deflected by a deflector coil 12 connected to a power source 13 for a deflector coil and bombarded against a thin film material 15 in the crucible 14 to heat the relevant very small surface area only. Hence, atoms for forming a thin film are formed. In the aforementioned constitution, a scanner means 16 is provided above the crucible 14, and an alternating magnetic field is applied to it so as to scann said electron beams right and left on the thin film material 15. Hence, a thin film having constant film thickness can be formed, even when the radius of rotation of the electron beam is changed to some extent. In addition, the number of exchanging the filament can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to E/B deposition machines, and more particularly to an electron beam that is scanned just before impinging on the thin film material to heat the thin film material.

An object of the present invention is to maintain uniformity in the thickness of a thin film in a thin film formed product.

Another object of the invention is to avoid frequent replacement of filaments and the like.

Conventionally, in order to form thin films on semiconductor substrates, etc., mainly 11
/ A method using a B vapor deposition machine is used. First, the principle of E/B vapor deposition will be explained using FIG.

1 is an accelerating voltage power source, 2 is a filament power source, 3 is a filament, 4 is a deflection coil, 5 is a deflection coil power source, 6 is a crucible, 7 is a thin film material, and 8 is a cooling tube. First, the material to be deposited, for example A7. AL20. A thin film material 7 such as the above is put into the crucible B. The strength of the electron beam is set by the strength of the filament 6, the beam is bent using the deflection coil 4, and high-density energy is concentrated on a minute area of the thin film material 7, causing atoms to fly out and form a thin film. Form a thin film on something.

In order to concentrate the electron beam on the thin film material 7, the radius of curvature becomes an issue and is determined by the following formula.

becomes.

γ: Radius of rotation (approximately) B: Magnetic flux density (/2) Sacrifice: Electron rest mass (k7) t: Electron charge CC) ■a: Accelerating voltage (V). What we focus on here is the magnetic flux density B and the accelerating voltage ■α
However, current E/B deposition has the following problems: the radius of rotation changes, the uniformity of the film thickness cannot be maintained, and the filament must be replaced frequently. .

The first problem is that when the filament reaches the end of its life, the electron beam weakens, the accelerating voltage inevitably changes, and the radius of rotation also changes. The second problem is that particles of evaporated material tend to adhere to the filament, which causes the strength of the filament to change quickly, causing problems such as changes in the radius of rotation. If this radius of rotation deviates, problems such as always heating a certain part of the thin film material deviating from the heated part or even completely deviating from the heating part occur, and the film thickness of the thin film to be formed will not be constant. I tried to correct this by adjusting the voltage of the deflection coil power supply and the filament power supply, but the experiment had to be repeated several times, which was time-consuming and a serious problem, so I immediately replaced the filament itself with a new one. was.

The present invention eliminates the above-mentioned drawbacks and will be described in detail below.

First, as shown in FIG. 2, an E/B vapor deposition machine was prototyped, which was equipped with a scanner device (which applied an alternating magnetic field and swung the electron beam from side to side) above the crucible 15.

In this invention, it is attached above the crucible.

The present invention will be described below using this device. First, a thin film material 15 to be vapor-deposited (AA was used this time) is placed in the crucible 14.The intensity of the electron beam is set by the strength of the filament 11.The beam is deflected using the deflection coil 12. The electron beam is bent at a certain point to concentrate high-density energy on a small area of the thin film material 15. At this time, the electron beam passes through the scanner 16, so it is scanned from side to side, covering the entire surface of the thin film material 15. runs, and At atoms scatter in each direction.

Further, even if the radius of rotation of the electron beam deviates, the thickness of the thin film formed is always kept constant because the thin film material 15 is not always heated at a fixed location. Furthermore, it goes without saying that the number of times the filament 11 must be replaced has been significantly reduced because the electron beam does not need to be removed from the scanner.

As described above, the present invention makes it possible to keep the thickness of the thin film uniform in the thin film formed object by installing a scanner device for scanning the electron beam, and also avoids frequent replacement of the filament. It is something that can be done. In the present invention, the scanner device is installed above the crucible, but similar results can be obtained even if the scanner device is installed where the electron beam is emitted, that is, above the deflection plate.

[Brief explanation of drawings]

FIG. 1 is a conventional diagram, and FIG. 2 is a diagram of the present invention. 1.9 Accelerating voltage power supply 2.10...Filament power supply 6.11...Filament・ 4.12...Deflection coil 5.13...Deflection coil power supply 6.14... Crucible 7.15 Thin film material 8.17...Cooling pipe 16・・・・・・・・・Scanner that's all Applicant: Suwa Seikosha Co., Ltd. Agent Patent Attorney Mogami

Claims (1)

[Claims] 1. In a beam generation source of an E/E vapor deposition machine, a high-density beam output from the beam generation source is applied to a thin film material, only a small portion of which is heated, and the beam is emitted from there. In the E/B evaporation machine, the electron beam of the F/E evaporation machine is scanned just before it hits the thin film material to heat the thin film material and evaporate it. An E/B vapor deposition machine characterized by: 2. The E/B vapor deposition machine according to claim 1, further comprising a device for scanning the upper part of the thin film material or the upper part of the deflection plate.