JPH0519319A - Method for producing amorphous thin film in which fine metal particles are dispersed - Google Patents

Abstract

(57) [Summary] [Object] An object of the present invention is to provide a manufacturing method capable of rapidly depositing a nonlinear optical material in which an amorphous thin film is heavily doped with metal fine particles. In a manufacturing method in which a means for forming an amorphous thin film and a means for forming metal fine particles are alternately formed, a SiO ₂ target 2 is formed by sputtering with an argon gas as a means for forming an amorphous thin film. . After that, as a means for forming fine metal particles, an organic metal complex producing apparatus 1
And irradiate the organometallic complex with the ECR plasma generator 3 for generating hydrogen plasma to form fine metal particles. The doping amount of Au in the metal fine particle-dispersed amorphous thin film produced by repeating this process was 5 atom%, and the particle diameter was 5 to 9 nm.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a non-linear optical material, and more particularly to a metal fine particle dispersed amorphous thin film.

[0002]

2. Description of the Related Art The optical non-linearity, especially the third-order non-linear susceptibility, is increased by doping glass with fine metal particles. This is because Optics Letters, Vol. 10, No. 10, pp. 511 (Optics Letters, V
ol. 10, No. 10, p. 511 (1985)). Au and Ag are used as the metal fine particles, and a metal salt reduction method is used as a method for producing the metal fine particle-doped glass.

Further, when the melting method is used, colored glass in which fine metal particles are mixed into a glass raw material to be shaped and then heat-treated to deposit a specific metal, and a metal colloid such as gold, silver or copper is deposited. It was manufacturing a metal fine particle dope glass called.

[0004]

[SUMMARY OF THE INVENTION However, the third-order nonlinear susceptibility of the fine particles of Au doped glass produced by the conventional metal salt reduction method and a melting method ^10-13 10 ^{over 12} esu
Value, which is very small compared to other nonlinear optical materials. It is considered that when the doping amount was increased by the conventional manufacturing method, the doping could not be performed uniformly, and the doping amount of the metal fine particles was 5 ppm or less, so that the value of the third-order nonlinear susceptibility became small. .

Further, in a non-linear optical material in which the metal fine particles are made of Ag or Cu other than Au, the glass of the fine particle dispersion medium is an oxide. Therefore, when dispersed in the glass, the metal fine particles are oxidized and the characteristics deteriorate. There was also the issue of being present.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a manufacturing method capable of rapidly depositing a nonlinear optical material in which an amorphous thin film is heavily doped with metal fine particles.

[0007]

In a manufacturing method in which a means for forming an amorphous thin film and a means for forming metal fine particles are alternately formed, an organometallic complex is used as a means for forming metal fine particles and hydrogen plasma is used. The conventional problem has been solved by a method for producing a metal fine particle-dispersed amorphous thin film in which metal fine particles are formed by irradiating an organometallic complex.

[0008]

Since the amorphous thin film and the metal fine particles are alternately formed independently of each other, the metal material does not react with the amorphous material. Further, since an organometallic complex is used, it can be supplied in the gas phase, and the reaction temperature can be lowered as compared with the reduction method or the melting method of the metal salt. Furthermore, since it is supplied in the vapor phase, there is no film thickness distribution and it can be formed uniformly on the substrate.

Irradiating the organometallic complex with hydrogen plasma,
Since the organometallic complex is reduced to form fine metal particles,
Since carbon and oxygen contained in the organometallic complex can be chemically changed to hydrocarbon or water, the fine metal particles are not oxidized.

[0010]

EXAMPLE In the method for producing an amorphous thin film in which fine metal particles are dispersed according to the present invention, the step of forming fine metal particles and the step of forming an amorphous thin film are alternately performed.

The metal fine particles to be dispersed in the amorphous thin film of the present invention may be any metal as long as it can exhibit a nonlinear optical effect, and particularly gold (Au), silver (Ag), copper (C).
If at least one of u) and Pt (platinum) is used,
Since the wavelength region of light is from the near-ultraviolet light region to the visible light region, the light source to be used is easily available and preferable.

Further, these metal fine particles can generate a large amount of gas at a low temperature and can be easily reduced by hydrogen plasma when an organometallic complex such as β-diketone is irradiated with hydrogen plasma. Examples of the β-diketone type organometallic complex preferable in the present invention include dimethyl gold hexafluoroacetylacetonate (A) which is an organometallic complex of gold.
u (CH ₃ ) ₂ (C ₅ HF ₆ O ₂ ), hereinafter DMG (hfa
Abbreviated as c). ) Or an organometallic complex of copper, bis (hexafluoroacetylacetonato) copper (Cu (C ₅ HF
₆ O ₂ ) ₂ , hereinafter abbreviated as Cu (HFA) ₂ . ) Etc.

The amorphous thin film of the present invention may be any one as long as it has an optical band gap larger than the wavelength region where the nonlinear optical effect of metal can be exhibited. In particular, when boron nitride, boron phosphide, boron arsenide, silicon nitride, silicon oxide, aluminum oxide, or aluminum nitride is used, the dispersibility of the metal fine particles is good.

As a plasma source for irradiating the organometallic complex of the present invention with hydrogen plasma, for example, usual hydrogen plasma generation such as ECR plasma generator, high frequency discharge or direct current discharge is applicable.

The method for producing the amorphous metal thin film in which fine metal particles are dispersed according to the present invention is, for example, a sputtering method or plasma CV.
Normal methods such as D method and electron beam evaporation method can be applied.

Examples of the present invention will be described below. Example 1 A schematic configuration diagram of the manufacturing apparatus used in this example is shown in FIG.
The manufacturing apparatus 1 uses SiO ₂Target 2, hydrogen plasma
ECR plasma generator 3 for generation, shutter 4, substrate
5, DMG (hfac) supply port which is an organometallic complex of gold
6, SiO₂By the high frequency power supply 7 that is supplied to the target of
It is configured. EC for hydrogen plasma generation
The R plasma generator 3 includes a microwave inlet 8 and a magnetic field generator.
The electromagnet 9 and the hydrogen gas supply port 10
The microwave is 2.45 GHz and the magnetic field strength is ECR.
It is 0.0875T that satisfies the condition. DMG (hfac)
Is set to a temperature of 24 to 43 ° C, and H₂For gas bubbling
More supplied. The substrate 5 was made of quartz glass.

First, when a SiO ₂ amorphous thin film is formed, argon is used as a sputtering gas and the pressure is set to 5 P.
set to a. The high frequency power supplied to the SiO ₂ target 2 was 250 W. After forming the SiO ₂ thin film to a thickness of 10 nm, the shutter 4 is used to stop forming the SiO ₂ thin film on the substrate. Then, DMG (hfac) is supplied to the manufacturing apparatus 1 through the DMG (hfac) supply port 6 together with H _2.
To supply. H ₂ was supplied at ₂ sccm. 1 sc of H ₂ gas is supplied from the hydrogen gas supply port 10 to the ECR plasma generator 3.
cm was supplied to form a hydrogen plasma. The microwave power was 100W. After forming the Au film to a thickness of 5 nm,
The supply of DMG (hfac) and the ECR plasma generator 3 are stopped. These steps were repeated 100 times to form a metal fine particle-dispersed amorphous thin film of 1.5 μm. This metal fine particle-dispersed amorphous thin film was heated in an electric furnace at 300 ° C. for 1 hour. The amount of Au doped in the obtained fine metal particle-dispersed amorphous thin film was 5 atom%, and the particle size was 5 to 9 nm.

Embodiment 2 FIG. 2 shows a schematic block diagram of the manufacturing apparatus used in this embodiment.
In the manufacturing apparatus shown in FIG. 1, the same parts have the same numbers. The manufacturing apparatus 11 includes a plasma CVD apparatus 12 for forming an amorphous thin film, an ECR plasma generator 3 for generating hydrogen plasma, a shutter 4, a substrate 5, a Cu (HFA) ₂ supply port 13 which is an organometallic complex of copper, Monosilane (Si
H ₄ ) It is configured in the supply port 14. An ECR plasma CVD method was used as the plasma CVD apparatus 12 for forming an amorphous thin film. As a basic configuration, the microwave introduction port 8, the magnetic field generating electromagnet 9 and the nitrogen gas supply port 15 are used. The microwave is 2.45 GHz and the magnetic field strength is 0.0875T satisfying the ECR condition. Further, the ECR plasma generator 3 for generating hydrogen plasma is
Since it is the same as that shown in the first embodiment, the description thereof will be omitted. Cu (HF
A) ₂ was set at a temperature of 95 to 120 ° C. and was supplied by H ₂ gas bubbling. The substrate 5 was made of quartz glass.

First, when a nitrogen silicon amorphous thin film is formed, the pressure of nitrogen gas and monosilane is set to 0.05 Pa.
It was set to 01 Pa. The microwave power was 100W.
After forming the silicon nitride amorphous thin film to a thickness of 5 nm, the supply of nitrogen gas and monosilane and the microwave power are stopped. Then, Cu (HFA) for supplying Cu (HFA) ₂ to the manufacturing apparatus 11 from _second supply ports 13 with H _2. H ₂ is 4 scc
m supplied. 1 sccm of H ₂ gas was supplied from the hydrogen gas supply port 10 to the ECR plasma generator 3 to form hydrogen plasma. The microwave power was 100W. After forming a Cu film with a thickness of 3 nm, supply of Cu (HFA) ₂ and E
The CR plasma generator 3 is stopped. 20 of these steps
Repeated 0 times to obtain a metal fine particle dispersed amorphous thin film of 1.6 μm.
Formed. This metal fine particle-dispersed amorphous thin film was heated in an electric furnace at 300 ° C. for 1 hour. The doping amount of Cu in the obtained metal fine particle-dispersed amorphous thin film was 10 atom%, and the particle diameter was 3 to 10 nm.

In this embodiment, the hydrogen plasma generator 3 is used.
Although the plasma CVD apparatus 11 and the plasma CVD apparatus 11 are individually provided and manufactured, the same apparatus may be used.

Example 3 The third-order nonlinear susceptibility χ ⁽³⁾ of the metal fine particle-dispersed amorphous thin film prepared by the method shown in Example 1 or 2 was measured. As a result, χ ⁽³⁾ of the metal fine particle-dispersed amorphous thin film in which the SiO ₂ thin film was doped with Au was 2.0 × 10 ⁻⁹ esu.
(Excitation wavelength 0.53 μm), and χ ^{(3) of the} amorphous metal thin film in which fine metal particles are dispersed by doping Cu into the silicon nitride amorphous thin film.
Was 5.0 × 10 ⁻¹⁰ esu (excitation wavelength 0.65 μm).

A Fabry-Perot resonator was manufactured using the Au metal fine particle-dispersed amorphous thin film manufactured in Example 1, and a very high switching speed of 1 psec or less was obtained.

In the first or second embodiment, Au, Cu
Although the organometallic complex of was used, Ag or Pt may be used.
The third-order nonlinear susceptibility χ ⁽³⁾ of the metal fine particle-dispersed amorphous thin film in which the silicon nitride amorphous thin film was doped with Ag using the method of Example 1 or 2 was 1.0 × 10 ⁻¹⁰ esu
(Excitation wavelength 0.4 μm).

Although the sputtering method and the plasma CVD method are used as the means for forming the amorphous thin film in the first or second embodiment, the electron beam evaporation method may be used. Also, an ECR plasma generator for generating hydrogen plasma and plasma CVD
Although ECR plasma was used as the apparatus, high frequency discharge or DC discharge may be used.

Although silicon nitride and silicon oxide are used as the amorphous material in the first or second embodiment, boron nitride, boron phosphide, boron arsenide, aluminum oxide or aluminum nitride may be used.

[0026]

As described above, in the manufacturing method in which the means for forming the amorphous thin film and the means for forming the metal fine particles are alternated, as means for forming the metal fine particles,
According to the production method of the present invention, which comprises using an organometallic complex to form fine metal particles for irradiating the organometallic complex with hydrogen plasma,
The surface of the metal fine particles can be formed without being oxidized, and the interface between the metal fine particle material and the amorphous material can be clarified, so that it is possible to exhibit a quantum effect. It is possible to prepare an amorphous thin film on which semiconductor metal fine particles are dispersed.

As described above, the present invention has excellent effects, and the industrial value of the present invention is high.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a manufacturing apparatus used in an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a manufacturing apparatus used in another embodiment of the present invention.

[Explanation of symbols]

1 Manufacturing Equipment 2 SiO ₂ Target 3 ECR Plasma Generator for Hydrogen Plasma Generation 4 Shutter 5 Substrate 6 DMG (hfac) Supply Port 7 High Frequency Power Supply 8 for Supplying to SiO ₂ Target 8 Microwave Inlet 9 Magnetic Field Generation Electromagnet 10 Hydrogen Gas supply port 16 H ₂ gas 17 DMG (hfac) 18 Metallic fine particle dispersed amorphous thin film 19 Substrate holder 20 Quartz glass 11 Manufacturing device 12 Plasma CVD device 13 for forming an amorphous thin film 13 Cu (HFA) ₂ supply port 14 Monosilane (SiH ₄ ) supply port 15 Nitrogen gas supply port

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Tsuneo Mikuro             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd.

Claims (3)

[Claims] 1. A method for producing a metal fine particle-dispersed amorphous thin film, which comprises alternately performing a step of irradiating an organometallic complex with hydrogen plasma to form fine metal particles and a step of forming an amorphous thin film. . 2. As the organometallic complex, Au, Ag, Cu,
2. The method for producing a metal fine particle-dispersed amorphous thin film according to claim 1, wherein at least one β-diketone organometallic complex of Pt is used. 3. A metal fine particle-dispersed amorphous thin film according to claim 1, wherein one of sputtering, plasma CVD, and electron beam evaporation is used as a means for forming the amorphous thin film. Manufacturing method.