JPH0570955A - Formation of thin film - Google Patents

Abstract

PURPOSE:To form thin films which are smooth and has good adhesion by executing the thin film formation by only the photo CVD method, then executing thin film formation by at least an ECR plasma CVD method, then executing the finishing of the film surface by only the photo CVD method. CONSTITUTION:The thin films are formed on a substrate 5 by the CVD method. A 1st stage for the thin film formation by only the photo CVD method to apply light energy for the thin film formation to gaseous raw materials 13 is, thereupon, executed. A 2nd stage of the thin film formation by at least the ECR plasma CVD method of the photo CVD method and the ECR plasma CVD method is thereafter executed. A 3rd stage for the finishing of the film surface by only the photo CVD method is then executed. The foundation for the good- quality films having the dense surfaces is formed in this way.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film forming method for forming a thin film on a substrate by a CVD method.

[0002]

2. Description of the Related Art As a thin film forming method of this type, conventionally,
Photo-CVD for applying light energy to source gas to form a film
And the ECR plasma CVD method in which plasma is generated by utilizing electron cyclotron resonance due to the interaction between a microwave and a magnetic field to form a film.

[0003]

According to the above-described photo-CVD method, there is an advantage that a thin film having a smooth surface and being dense and good in quality can be formed, and the thin film has good adhesion to the substrate. On the other hand, according to the ECR plasma CVD method,
The speed of forming a thin film is higher than that of the photo CVD method,
There is an advantage that a thin film can be formed speedily.

However, each of the thin film forming methods has the above-mentioned advantages as well as the following drawbacks, and it is an object of the present invention to solve these drawbacks.

First of all, the photo-CVD method has a drawback that it takes a long time to form a predetermined thin film and the efficiency is low because the thin film forming speed is slow.
The method D has a drawback that the film quality is poor because the composition of the thin film is inhomogeneous and easily contains impurities, and the stoichiometric composition cannot be controlled.

Therefore, an object of the present invention is to provide a thin film forming method capable of forming a thin film having a smooth surface and good adhesiveness in a short time while eliminating the drawbacks of the above-mentioned respective thin film forming methods and making the most of each advantage. Where it is.

[0007]

Means for Solving the Problems A feature of the present invention for achieving this object is to carry out the first step of forming a thin film by only a photo-CVD method for supplying light energy to a source gas for forming a thin film, After that, at least ECR plasma CVD among the optical CVD method and the ECR plasma CVD method is performed.
The second step of forming a thin film by the method is performed, and then the third step for finishing the film surface is performed only by the photo-CVD method.

[0008]

According to the characteristic means of the present invention, the first step is as follows.
A part of the thin film that is in contact with the substrate is formed. A nucleus for forming the film is formed on the substrate, and a crystal is subsequently grown. It can be said, so to speak, a step of forming the foundation of the film. That is, by carrying out the first step by the photo-CVD method, as described above, it is possible to form a base of a film having a smooth surface, a dense and good quality, and a good adhesion to a substrate. You can

Next, in the second step, the base of the film formed in the first step is further grown to form the core of the whole thin film. Therefore, if this step is performed quickly, it is effective in shortening the formation time of the entire thin film.
The process is a combination of the optical CVD method and the ECR plasma CVD method,
Or, by carrying out the ECR plasma CVD method, which can form a film more speedily, among both methods,
The core of the thin film can be formed quickly, and the total time for forming the thin film can be shortened.

In the third step, the surface of the film formed in the first and second steps is finished. In this step, the quality of the thin film as a whole is improved by forming a good quality thin film surface. You can In the present invention, since the third step is performed by the photo-CVD method similarly to the first step, even if the surface of the film is somewhat uneven, it is filled up and the thin film having a smooth surface and being dense and of good quality. Can be finished.

As described above, the thin film formed by stacking the first, second and third steps has good adhesion to the substrate, and the core of the film is formed by the ECR plasma CVD method. A thin film having a smooth surface can be obtained.

[0012]

As described above, according to the thin film forming method of the present invention, a thin film having good adhesion to a substrate and a smooth surface and good quality can be formed in a short time, and the efficiency of thin film production is improved. , It became possible to improve economic efficiency.

[0013]

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

FIG. 1 is a conceptual diagram showing an example of a CVD apparatus used to carry out the thin film forming method of the present invention.

A laser light source 1 is an example of a light source for carrying out the photo-CVD method. (The Hg lamp may be used as the light source.) The laser light 2 from the laser light source 1 is irradiated through the light irradiation window 6 in parallel with the substrate 5 installed on the substrate holder 4 in the film forming chamber 3. To be done. Further, a light confirmation window 7 for monitoring whether or not the film forming chamber 3 is surely irradiated with the laser beam 2 is provided at a position facing the light irradiation window 6 in the film forming chamber 3. A plasma generation chamber 8 is provided above the film formation chamber 3, and the plasma generated in the plasma generation chamber 8 is drawn into the film formation chamber 3 through a plasma drawing window 9. A waveguide window 12 for guiding the microwave 11 from the rectangular waveguide 10 is provided in the upper part of the plasma generation chamber 8, and the guided microwave 11 is provided around the waveguide window 12.
A magnetic coil 16 for applying a magnetic field to generate plasma in the plasma generation chamber is provided. Also, the plasma generation chamber 8
A raw material gas supply passage 14 for supplying the raw material gas 13 is also attached to this. On the other hand, an exhaust passage 15 for exhausting the consumed raw material gas 13 to the raw material gas supply passage 14.
Are attached to the film forming chamber 3.

In order to carry out the thin film forming method of the present invention with this apparatus, first, the substrate 5 is set on the substrate holder 4, and the raw material gas 13 is supplied into the film forming chamber 3 in the first step. As a process, the photo CVD method is performed. The first step is
This is performed by irradiating the laser light 2 from the light irradiation window 6 along the substrate 5 substantially in parallel, and in the first step, the base of the thin film is formed on the surface of the substrate 5. Next, as a second step, the film is grown by the ECR plasma CVD method to move to the formation of the core of the thin film. However, this second step needs to be performed at least by the ECR plasma CVD method, but may be performed by using the photo-CVD method together. Next, the third
The process is performed only by the photo-CVD method to finish the surface of the thin film.

It should be noted that reference numerals are added to the claims for convenience of comparison with the drawings, but the present invention is not limited to the configurations of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a CVD apparatus according to an embodiment.

[Explanation of symbols]

 5 Substrate 13 Raw material gas

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Shigeru Morikawa Inventor Shigeru-ku, Kyoto City, Kyoto Prefecture 17 Chudo-dera Minami-cho 17 Stock Company, Kansai Institute of New Technology (72) Inventor, Takashi Kobayashi 17 Naka-doji Minami-cho, Shimogyo-ku, Kyoto City, Kyoto Prefecture Kansai New Technology Research Center

Claims (1)

[Claims] 1. A thin film forming method for forming a thin film on a substrate (5) by a CVD method, which is a first method for forming a thin film only by an optical CVD method for supplying a raw material gas (13) with light energy for thin film formation. Process, after which the light C
At least EC of VD method and ECR plasma CVD method
A thin film forming method in which a second step of forming a thin film by the R plasma CVD method is performed, and then a third step for finishing the film surface is performed only by the photo CVD method.