JPH0726383A - Chemical vapor phase growing method for silicon oxide film - Google Patents

Abstract

PURPOSE:To easily produce a hard coating film excellent in denseness by using tetrakisdiethylaminosilane as the silicon source, adding an oxygen source, and forming a silicon oxide film on the surface of a body to be treated. CONSTITUTION:Tetrakisdiethylaminosilane is used as the silicon source, which is vaporized in a vaporizing device 7 maintained at about 60 deg.C and carried to a nozzle with nitrogen gas from a carrier gas cylinder 1. The silicon vapor in the nozzle is mixed with oxygen gas containing ozone from an oxygen gas cylinder 2 and from an ozone generator 3. The mixed gas is sprayed onto a substrate 8 to form a silicon oxide film under atmospheric pressure. By this method, a hard silcon oxide film which hardly causes cracking can be easily formed on the substrate 8 by using source materials which are easily handled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a silicon oxide film, and more particularly to a method for forming a silicon oxide film useful as an insulating film or a surface protective film.

[0002]

2. Description of the Related Art Chemical Vapor Deposition (Chemical Vapor)
The Por Deposition (CVD) method has been widely put into practical use as a method capable of mass-producing high-performance films. Silane or tetraethoxysilane (TEOS) is used as a silicon source for a chemical vapor deposition method of a silicon oxide film. However, silane is ignited in air, and tetraethoxysilane is easily hydrolyzed by water in the air. Further, the film obtained by the tetraethoxysilane-ozone system is apt to crack.

[0003]

SUMMARY OF THE INVENTION The present invention provides a silicon oxide film that is hard and does not easily crack and has a wide range of uses as an insulating film or a surface protective film by using a raw material that is easy to handle.
It is to provide a new chemical vapor deposition method that can be easily synthesized.

[0004]

[Means for Solving the Problems] Tetrakisdiethylaminosilane is used as a silicon source, and an oxygen gas containing ozone is added to the silicon source gas as an oxygen source to obtain glass, metal, or plastic at a substrate temperature of 200 ° C. or higher. A chemical vapor deposition method characterized by growing a film of silicon oxide that is hard, dense, and is resistant to cracking on the surface of an object to be processed such as.

[0005]

According to the method of the present invention, it is possible to easily grow a film of silicon oxide on a surface of an object to be treated containing plastic, using a raw material which is safe in handling, in a small number of steps and at a low temperature. it can.

[0006]

EXAMPLES Examples of the present invention will be described below. FIG. 1 shows a schematic diagram of a film forming apparatus. Using tetrakisdiethylaminosilane as a silicon source, this was vaporized in a vaporizer (7) kept at 60 ° C., and nitrogen gas (flow rate 300 cm
³ / min) (1) was transported to the nozzle as a carrier gas. 463ppm of ozone as an oxygen source in the nozzle
Was mixed with an oxygen gas containing oxygen (flow rate 100 cm ³ / min), and the mixed gas was sprayed onto the substrate (8) to form a film under atmospheric pressure. Borosilicate glass was used as the substrate (8). When the reaction was carried out at a substrate temperature of 200 ° C. or higher, a transparent film of silicon oxide having good adhesion to the substrate was obtained. FIG. 2 shows an Arrhenius plot of the film formation rate. The formed silicon oxide film was evaluated as follows. The infrared absorption spectrum was measured by a fast Fourier transform infrared spectrophotometer.
FIG. 3 shows infrared absorption spectra of the thin films synthesized at the substrate temperature, 200 ° C., 300 ° C. and 400 ° C. Wave number 10
80 cm ^-1, the absorption peak around 800 cm ^-1 and 460 cm ^-1 is based on Si-O bonds. The hardness of the film was measured by dynamic indentation hardness using an ultra-fine hardness meter. The results are shown in Fig. 4. The etching rate of the film is HF:
The measurement was performed using an etching solution in which HNO ₃ : H ₂ O was mixed in a weight ratio of 3: 2: 69. Results are shown in FIG. Comparative Example A silicon oxide film was formed by using tetraethoxysilane instead of tetrakisdiethylaminosilane. An Arrhenius plot of the film formation rate is shown in FIG. Substrate temperature 200 ℃,
The infrared absorption spectrum of the thin film synthesized at 300 ° C. and 400 ° C. is shown in FIG. The dynamic indentation hardness is shown in FIG. The etching rate is shown in FIG. As can be understood from the infrared absorption spectra of FIGS. 3 and 6, it can be seen that the silicon oxide film formed by the method of the present invention is similar in film quality to the silicon oxide film formed of tetraethoxysilane. As understood from the dynamic indentation hardness of FIG. 4 and the etching rate of FIG. 5, the silicon oxide film formed by the method of the present invention is harder than the silicon oxide film formed of tetraethoxysilane and has a smaller etching rate. It can be seen that the denseness of the film is excellent. Although the present invention has been variously described with reference to the preferred embodiments, the present invention is not limited to the embodiments and many modifications can be made without departing from the spirit of the invention. Is.

[Brief description of drawings]

FIG. 1 is a schematic diagram of an apparatus.

FIG. 2 is a diagram showing an Arrhenius plot of film formation rate.

FIG. 3 is a diagram showing an example of an infrared transmission spectrum of a film synthesized using tetrakisdiethylaminosilane at three kinds of substrate temperatures.

FIG. 4 is a diagram showing the dynamic indentation hardness of a film.

FIG. 5 is a diagram showing an etching rate of a film.

FIG. 6 is a diagram showing an example of infrared transmission spectra of a film synthesized using tetraethoxysilane at three kinds of substrate temperatures.

[Explanation of symbols]

 1 Carrier Gas Cylinder 2 Oxygen Gas Cylinder 3 Ozone Generator 4 Gas Flow Controller 5 Temperature Detector 6 Electric Furnace 7 Silicon Source Material 8 Substrate (Workpiece)

Claims (2)

[Claims] 1. A chemical vapor deposition method characterized in that tetrakisdiethylaminosilane is used as a silicon source, and an oxygen source is added to the silicon source to grow a film of silicon oxide on the surface of the object to be treated. 2. The chemical vapor deposition method according to claim 1, wherein the oxygen source is oxygen gas containing ozone.