JPS6286732A - Formation of compound film - Google Patents

Abstract

PURPOSE:To form a good quality film having no damage and contamination with the temperature of a sample held at low temperature by supplying the elements forming the film in the form of a beam. CONSTITUTION:There exist a sample 1 and a sample stand 2 in a vacuum and an Si particle bean and an O2 molecular beam are irradiated on the surface of the sample 1. The sample stand 2 is provided with a sample heating means 3, as required. The Si particle beam and O2 beam particules are bonded on the sample surface or in its vicinity and an SiO2 film is formed on the sample surface. At this time, if the O2 molecular beam is turned into a hot O2 molecular beam, the bond of SiO2 is easily formed and the SiO2 film of good quality is formed. Moreover, an Si atom-containing molecular beam may be used as well instead of the Si particle beam.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a method for forming a compound film on a solid surface, and particularly to a method for forming an oxide film or a nitride film suitable for semiconductor processes.

[Background of the invention]

Conventionally, for example, a silicon oxide film (SiOx film) has been formed by placing a silicon substrate in a high temperature (approximately 1000° C.) oxygen gas atmosphere or in oxygen plasma. However, the previous method had a problem in that the range of application was limited because the substrate became high temperature.

In addition, the latter method has the problem of damage and contamination occurring in the 5iOz film and at the interface between the 5iOz and the Si substrate (for example, Niss, Bourinil and M. Bakal; Plasma Chemistry and Plasma Processing, S., Gourrier and M. ,
Bacal; PlasIIla Chemistry
and Plasma Processing, )V
OII, Na3, 217 (1981)).

[Purpose of the invention]

An object of the present invention is to provide a method for forming a compound film (particularly an oxide film and a nitride film) which is free from damage and contamination at low temperatures using two atomic molecules, a cluster beam, or a hot molecular beam. .

[Summary of the invention]

For example, when forming a 5iOz film, the present invention enables Si atoms and O atoms to be simultaneously (or
This method provides a method of supplying (alternately). According to this method, a 5i02 film (generally a compound film) can be formed on any substrate at low temperature. However, the problem in this case is that sufficient chemical bonds (5i-0 membrane bonds in the case of the Si02 film) may not be formed and a good quality compound film may not be formed. Therefore.

This patent is characterized in that the elements forming the compound film are supplied in the form of a beam (particle beam).

Here, the beam refers to a flow of particles whose velocity distribution is anisotropic. By supplying it as a beam, it is possible to strictly control the amount of elements forming the compound film, and it is possible to form a film with just the right amount of constituent elements. Further, if necessary, by using a hot molecular beam or a cluster beam, sufficient chemical bonds can be formed in the film. A hot molecular beam is a beam of molecules whose molecular vibration levels are excited, and is a molecular beam with high chemical reactivity.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIG. In the example, there is a sample 1 and a sample stage 2 in a vacuum (here, a pressure of 1 atmosphere or less is referred to as a vacuum), and a beam of Si particles (Si atoms, Si molecules, or Si clusters) and 02 molecules are placed on the surface of the sample 1. The beam is being irradiated. The sample stage 2 is provided with a sample heating means 3 as required. Si
The particle beam and Ox beam particles combine at or near the sample surface to form an S i 02 film on the sample surface. At this time,
When the 02 molecule beam is changed to a hot 02 molecule beam (02 molecules excited by molecular vibration), 5iOz bonds are easily formed and a high quality Sio2 film is formed. Also, instead of a Si particle beam, molecules containing Si atoms (for example, 5
An iHa or SiF beam can also be used. The reaction at this time is, for example, when using 5iHa and a hot 0x (denoted as Oz*) beam, 5iHa+ 026→ S i Oz+ 2
It is Hz. So far, we have talked about silicon oxide films (Sift films), but if we use N2 molecular beams instead of 02 molecular beams and hot Nz (Nz*) beams instead of Ox rebeams, silicon nitride films ( SisNt) film can be formed.
AQ particle beam, W particle beam, Ti particle beam, M instead of Si particle beam.

AQ, W, Ti, Mo using particle beams, Ta particle beams, or similar particle beams.

An oxide film or nitride film of Ta or a similar material can be formed.

Since the method of the present invention does not use plasma, no damage or contamination is formed in the compound film or at the interface. Also,
Since chemical bonds (for example, Si--) are formed sequentially during film formation, there is no need to heat the sample to a high temperature.

FIG. 2 shows another embodiment of the invention. The difference from the embodiment of FIG. 1 is that the 5FII molecular beam or the hot 0
The reason is that the SiJM molecules and SFe molecules that did not react with 02 react like Si+2SFP, → SiF number ↑ + 28F ↓, and the excess 5iJfi molecules are removed. In order to
This is because an iOx film is formed.

If a hot SFB beam is used instead of the SFe molecular beam, excess Si atoms can be removed more efficiently. Instead of the SFe molecule (or hot 5Fs) beam, F2. Molecules containing halogen elements such as COx and NFs (
Alternatively, a similar effect can be obtained by using a beam of these hot molecules.

〔Effect of the invention〕

As described above, by using the method of the present invention, a high-quality film without damage or contamination can be formed while keeping the sample (substrate) temperature at a low temperature.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of a compound film forming method showing one embodiment of the present invention, and FIG. 2 is an explanatory diagram of a compound film forming method showing another embodiment of the present invention. 1... Sample, 2... Sample stage, 3... Sample heating means. Figure 1 γ Figure 2

Claims (1)

[Claims] 1. A compound film characterized in that a sample is held in vacuum and atoms or molecules containing elements constituting the compound are supplied as a beam onto the surface of the sample to form a compound film. Formation method. 2. The beam includes at least a Si particle beam and an O
_The method for forming a compound film according to claim 1, comprising a two-molecule beam. 3. The compound film forming method according to claim 2, wherein the O_2 molecular beam is a hot O_2 beam. 4. At least a Si particle beam and N_ as the beam
2. The method for forming a compound film according to claim 1, which comprises a bimolecular beam. 5. The compound film forming method according to claim 4, wherein the N_2 molecular beam is a hot N_2 beam. 6. The compound film forming method according to any one of claims 1 to 5, characterized in that an SF_6 beam, an F_2 beam, a molecular beam containing a halogen element, or a hot molecular beam thereof is added.