JPH03187951A - Semiconductor-containing glass - Google Patents

Abstract

PURPOSE:To obtain semiconductor-containing glass exhibiting a large quantum size effect containing fine crystal of specific semiconductor. CONSTITUTION:The aimed semiconductor-containing glass contains at least a specifies of semiconductor fine crystal selected from the group consisting of PbSe, PbTe, ZnTe, CuBr and CuI. In this case, the glass matrix may be silica glass or multi-component glass. Content of the semiconductor fine crystal is not specifically restricted. Besides, also granular diameter of the semiconductor fine crystal is not specifically restricted, while <=1000Angstrom , especially <=100Angstrom is preferable. Said semiconductor-containing glass is preferably produced by sol-gel method from the viewpoints of containing concentration of semiconductor fine crystal, uniformity of size of the semiconductor fine crystal, degree of freedom in shape of resultant glass and looseness of restriction on species of semiconductor able to be contained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a semiconductor-containing glass containing semiconductor microcrystals. The semiconductor-containing glass of the present invention is used as a glass material having a large nonlinear optical effect used in the field of optical information, such as optical switches and optical wavelength conversion elements.

[Background technology] Glass containing semiconductor microcrystals can be used as an optical switch because of the following properties: ■ It has optical bistability; ■ It has a photorelaxation time on the order of ps (picoseconds); ■ It has a quantum size effect. It is attracting attention as a nonlinear optical material that can be used for optical wavelength conversion devices, etc.

Glass containing such semiconductor microcrystals (hereinafter referred to as semiconductor-containing glass) includes approximately 1% CdSX.
Multicomponent glasses containing S e (1-X) microcrystals are generally known and commercially available as filter glasses. This semiconductor-containing 7-shirasu is produced by heating a glass raw material serving as a matrix and a semiconductor raw material to form a Noblas melt, and then rapidly cooling and reheating the glass melt.

However, conventional semiconductor-containing glass produced by such a melting method has a low concentration of semiconductor microcrystals due to volatilization of the semiconductor raw material during the preparation of the glass melt, and the semiconductor microcrystals are disordered during reheating treatment after rapid cooling. It is hard to say that it is useful as a nonlinear optical material because the size of the semiconductor microcrystals is not uniform due to the fact that it grows, and it is difficult to make it into a thin film.

For this reason, for the purpose of improving the concentration of semiconductor microcrystals, making the size of semiconductor microcrystals uniform, or making the semiconductor microcrystals thinner, the sol-gel method, CVD method, sputtering method, simultaneous vapor deposition method, lithography method, porous glass method, etc. Various attempts have been made to fabricate semiconductor-containing glasses using new amorphous material fabrication techniques, such as the use of .

At the same time, attempts have been made to obtain semiconductor-containing silica glasses using various semiconductors in order to obtain semiconductor-containing glasses having various nonlinear optical properties and optical properties.

Along with this, the above-mentioned Cd S * S e <1-
In addition to semiconductor-containing glasses containing x+ microcrystals, semiconductors include CuS, 'CdS, CuC1, Au, Si.

Mn2O3, I n/GaAs5GaAsSI nP
SCdSeSZnSeSCdTeSCdSxS e (
1-x-y) Semiconductor-containing glasses containing microcrystals or microparticles such as Te y have been prototyped.

[Object of the Invention] In view of the current state of semiconductor-containing glasses, an object of the present invention is to provide a semiconductor-containing glass containing a new semiconductor substance.

[Structure of the Invention] The present invention has been made to achieve the above object, and the semiconductor-containing glass of the present invention includes pbSe, PbTe,
, ZnTeXCuBr, and CuI.

The present invention will be explained in detail below.

As mentioned above, the semiconductor-containing glass of the present invention includes PbS,
Pb5eSPbTeSZnTeSCuBr and CuI
The glass matrix may be silica glass or multicomponent glass.

The content of semiconductor microcrystals is not particularly limited.

In addition, the particle size of semiconductor microcrystals is not particularly limited, but if the particle size exceeds 1,000 particles, light will be scattered, the transmittance will decrease, and the quantum size effect will be significantly reduced, so optical materials cannot be used. Since it is inappropriate as
It is preferably 0 Å or less, particularly 100 Å or less.

The semiconductor-containing glass of the present invention has loose restrictions on the concentration of semiconductor microcrystals, the uniformity of the size of semiconductor microcrystals, the degree of freedom in the shape of the obtained glass, and the types of semiconductors that can be contained. For these reasons, it is preferable to manufacture by the sol-gel method.

In producing the semiconductor-containing glass of the present invention by the sol-gel method, a sol solution containing metal elements and non-metal elements that are raw materials for semiconductors, a sol solution in which a semiconductor is dissolved, and a compound that becomes a semiconductor upon reduction are prepared. By preparing a sol solution of any of the dissolved sol solutions, gelling this sol solution and drying it to obtain a dry gel, and heat-treating this dry gel before vitrifying it, or by heat-treating it during vitrification, Precipitating semiconductor microcrystals; ■ Preparing a sol solution containing either a metal element or a non-metal element that is a raw material for a semiconductor, making this sol solution into a wet gel, and then forming a semiconductor into this wet gel. Semiconductor microcrystals are precipitated by impregnating a solution containing the remaining one of the metallic element and the non-metallic element to form a dry gel, and then heat-treating the dry gel before vitrifying it or by heat-treating it during vitrification. ■ Preparing a sol solution containing either a metal element or a non-metal element that is a raw material for a semiconductor, gelling it, and drying it to obtain a dry gel containing one of the metal elements and non-metal elements that make up the semiconductor. After impregnating the dry gel with a solution containing the other one, semiconducting microcrystals are precipitated by heat-treating the dry gel before vitrifying it or by heat-treating it during vitrification. The solution is gelled to form a wet gel, and this wet gel contains a solution containing metal elements and non-metal elements that are raw materials for semiconductors,
A dry gel is prepared by impregnating it with either a solution in which a semiconductor is dissolved or a solution in which a compound that becomes a semiconductor upon reduction is dissolved, and then this dry gel is heat-treated before vitrification, or during vitrification. Semiconductor microcrystals are precipitated by heat treatment. ■ A sol solution according to the composition of the glass matrix is gelled to form a dry gel, and a solution containing metallic and nonmetallic elements, which are the raw materials for semiconductors, and the semiconductor are dissolved in this dry gel. After impregnating the dry gel with a solution containing either a solution containing a compound that becomes a semiconductor when reduced or a solution containing a compound that becomes a semiconductor when reduced, the dry gel is heat-treated before vitrification, or by heat treatment during vitrification. A known method such as precipitating crystals can be used.

Preparation of a sol solution containing metal elements that are raw materials for semiconductors is as follows:
For each element of PbSZn and Cu, simple metals, metal oxides, metal halides, inorganic acid salts (nitrates, phosphates, etc.), organic acid salts (acetates, oxalates, etc.), metal organic compounds (metal alkoxides, alkyl When producing silica glass or multi-component glass by using sol-gel method using silica glass or multi-component glass using metal compounds (metal compounds, etc.), metal complexes (chelate compounds, etc.), etc., as they are, or as an aqueous solution, an organic solvent solution, or an inorganic solvent solution. This can be done by mixing the sol solution to be used.

In addition, for the preparation of a sol solution containing nonmetallic elements that are raw materials for semiconductors, for each element of Se, Te5Br, and I,
Inorganic compounds that react with metals to form semiconductors (selenic acid, selenite, selenium dioxide, selenium tetrachloride, selenyl chloride, telluric acid, tellurite acid, tellurium dioxide, tellurium tetrachloride, ammonium selenate, tellurium) ammonium acid, hydrobromic acid, hydroiodic acid, ammonium bromide,
ammonium iodide, etc.), organic compounds that react with metals to form semiconductors (selenourea, pia-selenol, selenate ester, tellurate ester, selenium alkoxide,
(tellurium alkoxide, etc.) as it is or as an aqueous solution, an organic solvent solution, or an inorganic solvent solution, and mix this with a sol solution used when manufacturing silica glass or multicomponent glass by the sol-gel method. This can be done by

To prepare a sol solution in which a semiconductor is dissolved, CuBr is added to a sol solution used when manufacturing silica glass or multi-component glass by the sol-gel method.

Either CuBr2, CuI or CuI2 and an organic solvent such as acetonitrile, acetylacetone or methanol are added separately and stirred, or the above sol solution and CuBr, C
This can be carried out by mixing with the above-mentioned organic solvent solution such as uI.

A sol solution containing dissolved compounds that become semiconductors when reduced is prepared by using zinc tellurate, lead selenate, lead tellurate, steel bromate, copper iodate, a mixture of zinc acetate and tellurium powder, lead nitrate and selenium dioxide. A mixture of lead acetate and tellurium tetrachloride, a mixture of copper nitrate and ammonium bromide, a mixture of copper acetate and iodine, etc. are prepared in an aqueous solution, an organic solvent solution, or an inorganic solvent solution. This can be carried out by mixing silica glass or a sol solution used in producing multi-component glass.

When a wet gel or dry gel containing one of a metal element and a non-metal element, which is a raw material for a semiconductor, contains a solution containing the other one of a metal element and a non-metal element constituting a semiconductor, the above-mentioned wet A method of adding a solution containing the above-mentioned metal element or a solution containing a non-metal element to the gel or dry gel, a method of immersing the above-mentioned wet gel or dry gel in the solution containing the above-mentioned metal element or non-metal element, etc. be able to.

A wet gel or dry gel obtained by gelling a sol solution according to the composition of the glass matrix, a solution containing metal elements and non-metal elements that are raw materials for semiconductors, a solution in which a semiconductor is dissolved, or a solution that becomes a semiconductor by reduction. When impregnating any of the solutions in which the compound is dissolved, use methods such as adding one of the above solutions to a wet gel or dry gel, or immersing a wet gel or dry gel in one of the above solutions. I can do it. Note that the solution containing metal elements and nonmetallic elements that are raw materials for semiconductors can be prepared in the same manner as the solutions containing metal elements that are raw materials for semiconductors, or the solutions containing nonmetallic elements that are raw materials for semiconductors. Obtainable.

The composition of the sol solution used to obtain the semiconductor-containing glass of the present invention by the sol-gel method includes metallic elements and/or non-metallic elements that are raw materials for semiconductors, semiconductors, or compounds that become semiconductors by reduction (hereinafter referred to as semiconductors). Except for the case where semiconductor microcrystalline raw materials are included), the use of semiconductor-containing glass or the reflectance, refractive index, and thermal expansion coefficient required for semiconductor-containing glass is not limited as described above. The optimum composition can be selected depending on characteristics such as weather resistance.

That is, SiO2, Al2O3, ZrO2, Tio2
, B203 , P205 , PbO, Bad.

Metal alkoxides corresponding to ordinary glass-constituting oxides such as 1 SrO1Li20, Na, O, and 20 (in this specification, Si alkoxides are also included in metal alkoxides) and/or derivatives thereof (for example, methyl In addition to triethoxysilane, 3-aminopropyltriethoxysilane, and trifluoropropyltrimethoxysilane materials, metals, metal oxides, metal halides,
Using metal inorganic acid salts (nitrates, phosphates, etc.), metal organic acid salts (acetate, oxalate, etc.), metal organic compounds (alkyl metal compounds, etc.), metal complexes, etc. as raw materials as necessary,
A sol solution can be prepared by blending these raw materials according to the composition of the glass matrix of the intended semiconductor-containing glass.

When the semiconductor microcrystal raw material is included in this sol solution, the addition timing may be before, during, or after the hydrolysis of the metal alkoxide and/or its derivative.

Wet gelation of the sol solution and dry gelation of Wet Gel 2 are the same as the processing in the normal sol-gel method, except for the case where the semiconductor microcrystal raw material is included in the wet gel, and for example, it is carried out as follows. be able to.

First, the sol solution is hydrolyzed to form a wet gel. Hydrolysis is carried out by mixing the metal alkoxide and/or its derivative with water and stirring. In addition, when using Si alkoxide and/or its derivative and another metal alkoxide and/or its derivative, the Si alkoxide and/or its derivative, which has a slow hydrolysis rate, is first hydrolyzed, and then the other metal alkoxide and/or its derivative are used. and/or a derivative thereof and mix;
Further hydrolysis is also possible.

Raw materials other than the metal alkoxide and its derivatives are used before hydrolysis of the metal alkoxide and/or its derivatives.
It can be added either during or after, but the timing of addition is selected depending on the nature of the raw material. Also,
Raw materials other than metal alkoxides and their derivatives do not need to be added in the form of a solution; any method of addition may be used as long as they are dissolved and homogeneous in the sol solution before gelation.

The amount of water used for hydrolysis depends on the type of metal alkoxide and/or its derivative used as the main raw material, but
The amount may be about twice the molar amount of the metal alkoxide and/or its derivative, and by using water once, the hydrolysis time can be shortened. moreover,
The reaction time can be shortened by using an acid such as hydrochloric acid, nitric acid, or acetic acid, or a base such as NH40H, pyridine, or piperazine as a catalyst during hydrolysis. The amount of the catalyst may be approximately IXIO-3 to 1 times the molar amount of the metal alkoxide and/or its derivative 1.

Although hydrolysis proceeds at room temperature, the reaction time can be further shortened by heating to about 40 to 200°C. However, temperatures exceeding 80°C are unfavorable because rapid evaporation of the solvent, water, metal alkoxide, and/or its derivatives occurs. It can be prevented.

4 A wet gel can be obtained by performing such hydrolysis treatment.

When a semiconductor microcrystal raw material is included in a wet gel, as described above, a solution containing a semiconductor microcrystal raw material is added to this wet gel, or the sea urchin :/togel is immersed in a solution containing a semiconductor microcrystal raw material. do.

The drying time when converting a wet gel into a dry gel depends on the size and shape of the wet gel, the amount of remaining water, the drying temperature, etc., and is usually about 10 hours to 4 weeks. Thereafter, by gradually heating the temperature up to 150° C., a dry gel with less residual moisture can be obtained. If the heating rate is increased, rapid contraction of the gel may occur and breakage may occur, so heating is usually carried out at 10°C/hour or less.

When the semiconductor microcrystalline raw material is included in the dry gel, as described above, a solution containing the semiconductor microcrystalline raw material is added to this dry gel, or this sea urchin sotogel is immersed in a solution containing the semiconductor microcrystalline raw material.

When the semiconductor-containing glass of the present invention is produced by the sol-gel method, the semiconductor-containing glass is produced by heat-treating the dry gel obtained as described above before vitrifying it, or by heat-treating it during vitrification. Precipitate crystals.

When precipitating semiconductor microcrystals by heat treatment before vitrifying the dry gel, heat treatment is performed at room temperature to 400°C in air, oxidizing atmosphere, inert gas atmosphere, or reducing atmosphere.
It is preferable to heat it to .

After this, in air, oxidizing atmosphere, inert gas atmosphere,
or 400-1300°C in a reducing atmosphere
By heating to , the dry gel precipitated from the semiconductor microcrystals is vitrified, and the semiconductor-containing glass of the present invention can be obtained. If vitrification is performed at a temperature lower than 400°C, the solidified gel will not be sufficiently vitrified and water and organic matter will remain, which is not preferable. In addition, the vitrification is 1
If the temperature exceeds 300°C, crystallization of the glass matrix, coarsening of the semiconductor microcrystals, oxidation, volatilization, and decomposition of the semiconductor microcrystals occur, which is not preferable.

When semiconducting microcrystals are precipitated by heat treatment during vitrification of dry gel, it is necessary to precipitate semiconducting microcrystals in the air, in an oxidizing atmosphere, in an inert gas atmosphere, or in a reducing atmosphere.
Preferably, the temperature is heated to 1300°C. This heat treatment causes JJI extrusion of the semiconductor microcrystals and vitrification of the dry gel, making it possible to obtain the semiconductor-containing glass of the present invention.

Note that the size of semiconductor microcrystals depends on the atmosphere, processing temperature, and processing time during which semiconductor microcrystals are precipitated, and the atmosphere and processing temperature during vitrification when vitrifying semiconductor microcrystals after precipitating them. and processing time. Furthermore, when semiconductor microcrystals are precipitated during vitrification, it depends on the atmosphere, treatment temperature, and treatment time during vitrification. Therefore, by appropriately selecting these processing conditions, a semiconductor-containing glass containing semiconductor microcrystals of any size can be obtained.

When producing the semiconductor-containing glass of the present invention by the sol-gel method, the shape of the semiconductor-containing glass obtained largely depends on the shape of the container used to gel the sol solution.
By appropriately selecting the shape of the container in step 7 when gelling the sol solution, a semiconductor-containing glass having a desired shape can be obtained. In addition, by applying the sol solution onto the substrate and then gelling and vitrifying it, it is possible to obtain semiconductor-containing glass in the form of a thin film, and repeating the application of the sol solution onto the substrate, gelling, and vitrifying a desired number of times. By this, a semiconductor-containing glass having a thick film shape can be obtained.

[Example] Examples of the present invention will be described below.

Example 1 Tetraethoxysilane [S i (OC2Hs)
]354.3g was dissolved in 0.15 mol/1 hydrochloric acid (H(1
) 30.0 g of aqueous solution and 76 ethanol (C2H50H)
．． It was gradually added dropwise to a mixed solution of 6 g with stirring. After all of the Si(OC2H5)4 was added, stirring was continued for an additional hour to obtain 460.8 g of a partially hydrolyzed solution of Si(OC2H5)4. Add lead acetate trihydrate [Pb (CH3C00)2.3H20] to this partially hydrolyzed solution.
A solution of 2.786 g dissolved in 60 g of methanol 8 (CH30H) was added and stirred for 1 hour. In addition, a solution of 0.552 g of selenium (Se) dissolved in 75.0 g of a 13 mol/11 nitric acid (HN O3) aqueous solution was diluted with H2090,Og and 76.6 g of C2H6OH, and 0-phenylenediamine [C6H4(NH2)
2 ] 7. A pia selenol solution prepared by adding 56 g was added to the above sol solution and stirred for 1 hour.

The obtained sol solution is transferred to a container made of polymethylpentene or polypropylene, left to stand, gelled and dried, and the PB
A dry gel containing the element and Se element was obtained.

This dry gel was placed in an electric tubular furnace and heated in the atmosphere at 400°C for 5 hours to oxidize and remove residual organic matter, and then the atmosphere was replaced with a mixed gas consisting of 3% H2 and 97% N2. By heating at 500°C for 2 hours while flowing H2/N2 mixed gas at a rate of 50ml/min, P
2% by weight for precipitation and vitrification of b5e microcrystals.
A semiconductor-containing glass of 9 was manufactured from 5i02 glass containing lead selenide (PbSe).

In this semiconductor-containing glass, only Pb5e crystals were observed by X-ray diffraction measurement, and no other crystals were present. In addition, the energy gap value obtained from the absorption edge of the optical absorption spectrum of this semiconductor-containing glass is 0.99.
eV, and this value is 0.74 eV compared to the energy gap value (0.25 e V) of a large Pb5e single crystal.
It was also expensive.

In order for semiconductor-containing glasses to have large nonlinearity, the development of quantum size effects has a large influence, and due to this quantum size effect, semiconductors with small particle diameters have large energy gaps.

Therefore, it can be seen that in the semiconductor-containing glass of this example, which has an energy gap value 0.74 eV higher than that of the Pb5e single crystal, the quantum size effect appears significantly.

Example 2 5i containing 5% by weight of lead telluride (PbTe) was prepared in the same manner as in Example 1 except that tellurium (Te) was used instead of Se and C6H40 (NH2)2 was not used.
A semiconductor-containing glass consisting of 02 glass was produced.

In this semiconductor-containing glass, only PbTe crystals were observed by X-ray diffraction measurement, and no other crystals were present. Furthermore, when the energy gap value of the PbTe crystal was determined in the same manner as in Example 1, it was found to be 1.23 eV. This energy gap value is due to the large PbTe
The energy gap value is 0.90 eV higher than that of a single crystal (0.33 e V), indicating that the quantum size effect is prominent.

Example 3 5% by weight of zinc telluride (ZnTe) was prepared in the same manner as in Example 2 except that zinc acetate trihydrate [Zn (CH3COO)2 .2H20] was used instead of Pb (CH3Coo)2 .3H20. A semiconductor-containing glass consisting of 5i02 glass was produced.

In this semiconductor-containing glass, only ZnTe crystals were observed by X-ray diffraction measurements, and no other crystalline substances were present. Furthermore, in the same manner as in Example 2, ZnT
The energy gap value of the e-crystal was found to be 2.5.
It was 5 eV. This energy gap value is similar to that of a large ZnTe single crystal (2.26 eV
), which is 0°29ev higher, indicating that the quantum size effect is prominent.

Example 4 460.8 g of a partially hydrolyzed solution of Si(OC2H5)4 was obtained in the same manner as in Example 1, and this partially hydrolyzed solution was
Zn(CH3C00)2・2H202,332g in CH
A solution dissolved in 60 g of 30H was added and stirred for 1 hour. Then, a solution of 2.792 g of tellurium tetrachloride (TeC14) dissolved in 100 g of C2H3oH was added at 3.5 mol/
A HNO3 aqueous solution 171.2g and C2H60H76
, 6g of the solution prepared by diluting it with 1
Stir for hours.

The obtained sol solution was converted into gel 2 in the same manner as in Example 3, dried to obtain a dry gel, and further heat-treated in the same manner as in Example 3 to obtain 5i02 containing 2% by weight of ZnTe.
A semiconductor-containing glass made of glass was manufactured.

In this semiconductor-containing glass, only ZnTe crystals were observed by X-ray diffraction measurement, and no other crystals were present. Furthermore, when the energy gap value of the ZnTe crystal was determined in the same manner as in Example 3, it was found to be 2.87 eV, which indicates that the quantum size effect appears significantly.

Example 5 460.8 g of a partially hydrolyzed solution of 5i (OC2H6) was obtained in the same manner as in Example 1, and to this partially hydrolyzed solution,
2.02g of cuprous bromide (CuBr) was dissolved in acetonitrile (
CH3CN) was added together with 150.0 g, and stirring was continued for 2 hours.

The obtained sol solution was gelated and dried in the same manner as in Example 1 to obtain a dry gel containing CuBr.

By heating this dry gel at 900°C in the air for 5 hours, CuBr microcrystals were precipitated and vitrified.
, manufactured a semiconductor-containing glass made of glass.

In this semiconductor-containing glass, only CuBr crystals were observed by X-ray diffraction measurement, and no other crystalline substances were present.

Example 6 A semiconductor-containing glass made of 5i02 glass containing 2% by weight of CuI was produced in the same manner as in Example 5 except that cupric iodide (CuI) was used instead of CuBr.

In this semiconductor-containing glass, only CuI crystals were observed by X-ray diffraction measurement, and no other crystalline substances were present.

[Effects of the Invention] As explained above, the semiconductor-containing glass of the present invention is a glass containing a new semiconductor as a semiconductor, and the semiconductor-containing glass of the present invention exhibits a large quantum size effect. .

4 Therefore, the present invention provides a new semiconductor-containing glass useful as a nonlinear optical material.

Claims (1)

[Claims] (1) A semiconductor-containing glass characterized by containing at least one semiconductor microcrystal selected from the group consisting of PbSe, PbTe, ZnTe, CuBr, and CuI.