JP2005263522A - Silicon particles, silicon powder and method for manufacturing silicon particles - Google Patents

Silicon particles, silicon powder and method for manufacturing silicon particles Download PDF

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JP2005263522A
JP2005263522A JP2004075521A JP2004075521A JP2005263522A JP 2005263522 A JP2005263522 A JP 2005263522A JP 2004075521 A JP2004075521 A JP 2004075521A JP 2004075521 A JP2004075521 A JP 2004075521A JP 2005263522 A JP2005263522 A JP 2005263522A
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silicon
particles
powder
nm
gas
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JP4791697B2 (en
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Taku Kawasaki
Hirosaku Kimura
Takuya Okada
Iichi Sato
井一 佐藤
拓也 岡田
卓 川崎
啓作 木村
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Denki Kagaku Kogyo Kk
Hirosaku Kimura
Iichi Sato
佐 藤 井 一
啓作 木村
電気化学工業株式会社
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Abstract

PROBLEM TO BE SOLVED: To provide high-purity silicon nanoparticles having high practicality as a raw material powder for high-performance light-emitting elements and electronic parts on an industrial scale.
Silicon particles having a particle size of 1 to 50 nm and a total amount of Na, Fe, Al, and Cl of 10 ppm or less.
[Selection figure] None

Description

  The present invention relates to nanometer (nm) size high-purity silicon particles and a method for producing the same.

  Silicon particles having a particle size on the order of nanometers (hereinafter referred to as “silicon nanoparticles”) have physical and chemical properties that are significantly different from those of bulk silicon. Collecting. For example, silicon nanoparticles have a band structure different from bulk silicon based on quantum confinement effects and surface level effects, and light emission phenomena that are not observed in bulk silicon are observed. Application as a raw material is expected.

  Ordinary silicon fine powder obtained by finely pulverizing silicon has physical and chemical properties almost identical to bulk silicon. In contrast, silicon nanoparticles have a fine particle size, a relatively small particle size distribution width, and high purity. For this reason, it is thought that peculiar properties, such as a luminescence phenomenon, which are remarkably different from bulk silicon are expressed.

  Conventionally, as a method for producing silicon nanoparticles, for example, (1) a second method in which silicon evaporated by a first high-temperature plasma generated between opposing silicon electrodes is generated by electrodeless discharge in a reduced-pressure atmosphere. (2) Method of separating and removing silicon nanoparticles from an anode made of a silicon wafer by electrochemical etching (Patent Document 2), (3) Halogen-containing organic A method of electrode reduction of a silicon compound using a reactive electrode (Patent Document 3) has been used.

JP-A-6-279015 Special table 2003-515459 gazette JP 2002-154817 A

  However, in the methods (1) and (2), it is difficult to improve productivity because the production rate of silicon nanoparticles is extremely low. In the method (3), since the raw material contains a halogen element such as Cl, which is likely to be mixed into the product, the total amount of Na, Fe, Al, and Cl is less than 10 ppm.

  Therefore, it has been extremely difficult to produce high-purity silicon nanoparticles useful as a raw material powder for high-performance light-emitting elements and electronic parts on an industrial scale.

  Therefore, the present inventors diligently studied whether there is a manufacturing method capable of producing high-purity silicon nanoparticles capable of realizing high-performance light-emitting elements and electronic components on an industrial scale. As a result, the silicon particle-containing silicon oxide produced by a vapor phase method using a specific raw material was heated under specific conditions, and then the excess silicon oxide was removed with hydrofluoric acid. As a result, it was found that high-purity nanometer-sized silicon particles having a relatively uniform diameter can be produced on an industrial scale, and the present invention has been completed.

  That is, the silicon particles of the present invention have a particle size of 1 to 50 nm and a total amount of Na, Fe, Al, and Cl is 10 ppm or less.

  In addition, the silicon powder of the present invention is characterized by containing 90% by mass or more of silicon particles having a particle diameter of 1 to 50 nm and a total amount of Na, Fe, Al, and Cl of 10 ppm or less.

  Furthermore, the method for producing silicon particles of the present invention includes a step of synthesizing a powder containing silicon oxide particles containing silicon particles by causing a gas phase reaction between monosilane gas and an oxidizing gas for oxidizing the monosilane gas. The method further comprises a step of removing the silicon oxide with hydrofluoric acid after holding the powder at 800 to 1400 ° C. under an inert atmosphere.

  The silicon particles of the present invention are nanoparticles having a relatively uniform particle size of 1 to 50 nm, and the total amount of Na, Fe, Al, and Cl is 10 ppm or less and has high purity.

  In general, silicon particles have a band structure different from that of bulk silicon based on the quantum confinement effect and the surface level effect, and the particle size when exhibiting a light emission phenomenon that is not observed in bulk silicon is 1 to 5 nm. In addition, it is said that the quantum well structure that is important when applied to an electronic component is recognized in an aggregate of particles having a uniform particle size of 10 nm or less. The particle size of the silicon particles of the present invention is 1 to 50 nm, and includes the range of particle sizes in which the quantum confinement effect, surface level effect, or quantum well structure is manifested.

  In addition, when silicon contains impurities such as Na, Fe, Al, or Cl, impurity levels are formed in the band structure, which causes a decrease in light emission efficiency in the light emitting element and malfunction of electronic components. Since the total amount of Na, Fe, Al, and Cl of the silicon particles of the present invention is 10 ppm or less, no impurity level is formed, and the above-described problems in the light emitting element and the electronic component do not occur.

  Therefore, unlike the conventional silicon nanoparticles, the silicon particles of the present invention are highly practical as a raw material powder for high-performance light-emitting elements and electronic parts.

  In addition, the silicon particle production method of the present invention uses a specific silicon-containing gas (monosilane gas) as a raw material, reacts with an oxidizing gas under specific conditions, and synthesizes a silicon oxide once containing silicon particles. In addition, this is a method in which excess silicon oxide is removed with hydrofluoric acid after heat treatment under specific conditions. Unlike conventional silicon nanoparticle production methods, it is highly productive and produced on an industrial scale. Is also possible. For this reason, it becomes possible to apply silicon nanoparticles to light-emitting elements and electronic components on an industrial scale, which is very useful industrially.

  The silicon particles of the present invention have a particle size of 1 to 50 nm, preferably 1 to 30 nm. If the particle size is out of this range, the quantum confinement effect, surface level effect, or quantum well structure suitable for application to light-emitting elements and electronic components will not be exhibited. Further, the total amount of Na, Fe, Al and Cl in the silicon particles of the present invention is 10 ppm or less, preferably 5 ppm or less. When the total amount of Na, Fe, Al, and Cl exceeds 10 ppm, the influence of impurities may occur on the characteristics of the light emitting element and the electronic component.

  The silicon powder of the present invention contains 90% by mass or more of the silicon particles of the present invention. If the content of the silicon particles of the present invention is 90% by mass or more, unnecessary particles can be removed as it is or by simple post-treatment, but if it is less than 90% by mass, removal of unnecessary particles is not easy.

  The silicon particles of the present invention are produced, for example, by removing silicon oxide after heat-treating silicon particle-containing silicon oxide particles synthesized from a gas phase using monosilane gas and oxidizing gas at a predetermined atmosphere and temperature. can do.

  Specifically, by reacting monosilane gas with oxidizing gas in the gas phase, a powder containing silicon oxide particles containing silicon particles is synthesized. The reaction is performed by introducing monosilane gas and oxidizing gas into the reaction vessel.

Here, the raw material which becomes a silicon source in the present invention is monosilane gas. When a silicon-containing gas other than monosilane gas, for example, chlorosilanes (SiH n Cl 4-n , n = 0 to 3) is used as a raw material, the total amount of Na, Fe, Al, and Cl exceeds 10 ppm.

  The oxidizing gas is not particularly limited as long as it oxidizes monosilane gas, but oxygen gas, air, water vapor, nitrogen dioxide, carbon dioxide, etc. can be used, and the points such as easy handling and ease of reaction control can be used. Therefore, oxygen gas is particularly preferable. In order to facilitate the reaction control, hydrogen, nitrogen, ammonia, carbon monoxide, as well as inert gases such as argon and helium, as well as inert gases such as argon and helium, are used for the purpose of diluting monosilane gas and oxidizing gas. A third gas such as can also be introduced into the reaction vessel.

  The reaction is preferably carried out while maintaining the temperature of the reaction vessel at 500 to 1000 ° C. and the pressure at 10 to 1000 kPa. A reaction vessel made of a high-purity material such as quartz glass is generally used, and its shape is not particularly limited, but a tube is preferred, and the axial direction of the tube is either vertical or horizontal. Also good. As for the heating method of the reaction vessel, any method such as resistance heating, high frequency induction heating, infrared radiation heating and the like can be used.

  The powder containing silicon oxide particles containing silicon particles generated in the reaction vessel is discharged out of the system together with the gas flow, and is collected from a powder collecting device such as a bag filter.

  The recovered powder is then held at 800-1400 ° C. under an inert atmosphere. By such treatment, the particle size of the silicon particles included in the powdered silicon oxide particles is adjusted to 1 to 50 nm. When the holding temperature is less than 800 ° C., the particle size of the silicon particles is less than 1 nm, impurities are likely to remain in the silicon, and the total amount of Na, Fe, Al, and Cl exceeds 10 ppm. Moreover, when it exceeds 1400 degreeC, the particle size of a silicon particle will exceed 50 nm.

  As the inert atmosphere gas, hydrogen, nitrogen, ammonia, carbon monoxide and the like can be used in addition to an inert gas such as argon and helium, but argon gas is particularly preferable from the viewpoint of easy handling and the like. .

  After adjusting the particle size of the silicon particles to be included, the powder containing the silicon oxide particles is added and dispersed in water. The dispersion is performed using ultrasonic waves or a stirrer, and it is particularly preferable to use ultrasonic waves. After the powder is dispersed and suspended in water, hydrofluoric acid is added to the suspension. The silicon particles contained in the silicon oxide particles are not dissolved by hydrofluoric acid, but the surrounding silicon oxide is dissolved and removed, so that only the silicon remains and the silicon particles of the present invention can be obtained. .

  Hereinafter, the present invention will be further described with reference to Examples and Comparative Examples.

<Example 1>
From a quartz glass reaction tube (inner diameter 50 mm, length 1000 mm) in which monosilane gas 0.16 L / min, oxygen gas 0.4 L / min and dilution nitrogen gas 17.5 L / min were maintained at a temperature of 700 ° C. and a pressure of 90 kPa. When introduced into a reaction vessel, a brown powder was produced. This was collected with a metal filter provided on the downstream side of the reaction tube.

It was 55 m < 2 > / g when the specific surface area of the collected produced | generated powder was measured by the BET 1 point method. When chemical analysis was performed, the main components were silicon (Si) and oxygen (O). Moreover, as a result of examining the bonding state of Si by the XPS (X-ray photoelectron spectrum) Si 2p spectrum, in addition to the peak attributed to the Si—O bond, a peak attributed to the Si—Si bond was observed and produced It was confirmed that silicon particles were included in the silicon oxide particles.

  After maintaining 20 g of this powder at a temperature of 1100 ° C. for 1 hour under an argon atmosphere, it was cooled to room temperature, 1 liter of distilled water was added, and the powder was further dispersed for 1 hour by ultrasonication to prepare a suspension. . To this was added 0.1 liter of 5% hydrofluoric acid (HF) and ultrasonic waves were applied for 30 minutes to dissolve and remove the silicon oxide. Thereafter, the suspension was filtered and washed using a membrane filter to separate the product and dried to obtain a silicon powder.

  The main component of this powder was Si, and it was confirmed by chemical analysis that the total amount of Na, Fe, Al, and Cl was 5 ppm. Furthermore, when the particle size of the particles contained in the powder was measured with a transmission electron microscope (TEM), it was 10 to 40 nm.

<Example 2>
Monosilane gas 0.08 L / min, oxygen gas 0.044 L / min, and argon gas 18 L / min for dilution were introduced into a reaction vessel composed of the same quartz glass reaction tube as in Example 1 maintained at a temperature of 750 ° C. and a pressure of 50 kPa. As a result, a brown powder was produced. This was collected in the same manner as in Example 1.

It was 150 m < 2 > / g when the specific surface area measurement of the collected production | generation powder was performed. As a result of chemical analysis, Si and oxygen as main components and the Si 2p spectrum of XPS were examined. As a result, a peak attributed to the Si—Si bond was observed, and the product was silicon oxide particles containing silicon particles. I confirmed that there was.

  A silicon powder was obtained in the same manner as in Example 1 except that 20 g of this powder was held at a temperature of 900 ° C. for 1 hour in a helium atmosphere. The main component of this powder was Si, and it was confirmed by chemical analysis that the total amount of Na, Fe, Al, and Cl was 8 ppm. Furthermore, when the particle size of the particles was measured by TEM, it was 2 to 24 nm.

<Comparative Example 1>
A silicon powder was obtained in the same manner as in Example 1 except that 20 g of powder composed of silicon oxide particles containing Si was held at a temperature of 1450 ° C. for 1 hour in an argon atmosphere.

  The main component of this powder was Si, and it was confirmed by chemical analysis that the total amount of Na, Fe, Al, and Cl was 4 ppm. Further, when the particle size of the particles was measured by TEM, it was a powder composed of particles of 35 nm or more containing 12% by mass of particles exceeding 50 nm.

<Comparative example 2>
A silicon powder was obtained in the same manner as in Example 1 except that 20 g of powder composed of silicon oxide particles containing Si was held at a temperature of 700 ° C. for 1 hour in an argon atmosphere.

  The main component of this powder was Si, and it was confirmed by chemical analysis that the total amount of Na, Fe, Al, and Cl was 18 ppm. Further, the particle diameter of the particles was measured by TEM, and the powder was composed of particles of 10 nm or less including 16% by mass of particles of less than 1 nm.

<Comparative Example 3>
A silicon powder was obtained in the same manner as in Example 2 except that 20 g of powder composed of silicon oxide particles containing Si was held at a temperature of 700 ° C. for 1 hour in a helium atmosphere.

  The main component of this powder was Si, and it was confirmed by chemical analysis that the total amount of Na, Fe, Al, and Cl was 23 ppm. Further, the particle diameter of the particles was measured by TEM, and it was confirmed that the powder was composed of particles of 6 nm or less including 40% by mass of particles less than 1 nm.

<Comparative example 4>
When the gas was introduced into the reaction vessel in the same manner as in Example 1 except that silicon tetrachloride (SiCl 4 ) gas frequently used as a raw material for polycrystalline silicon was used instead of monosilane gas, a brown powder was produced. This was collected in the same manner as in Example 1.

It was 45 m < 2 > / g when the specific surface area measurement of the collected production | generation powder was performed. As a result of chemical analysis, the main components were Si and oxygen, and as a result of examining the Si 2p spectrum of XPS, a peak attributed to the Si—Si bond was observed, and the silicon oxide powder particles in which the product contained silicon particles It was confirmed that.

  Using 20 g of this powder, silicon powder was obtained in the same manner as in Example 1. The main component of this powder was Si, and the particle size of the particles measured by TEM was 5 to 35 nm. In particular, the powder contained a large amount of chlorine (Cl), and the total amount of Na, Fe, Al, and Cl was 50 ppm. It was.

  According to the present invention, it is possible to synthesize a large amount of powder composed of nanometer-sized silicon particles on an industrial scale with high productivity without requiring a special electrolysis apparatus or plasma generation apparatus. By using it as a raw material powder, it can contribute to the practical application of functional materials such as new and high-performance light-emitting elements and electronic parts.

Claims (3)

  1.   Silicon particles having a particle diameter of 1 to 50 nm and a total amount of Na, Fe, Al, and Cl of 10 ppm or less.
  2.   A silicon powder characterized by containing 90% by mass or more of silicon particles having a particle size of 1 to 50 nm and a total amount of Na, Fe, Al, and Cl of 10 ppm or less.
  3.   A step of synthesizing a powder containing silicon oxide particles containing silicon particles by reacting a monosilane gas with an oxidizing gas for oxidizing the monosilane gas, and the powder under an inert atmosphere at 800 to 1400 ° C. And a step of removing the silicon oxide with hydrofluoric acid after being held in step 1.
JP2004075521A 2004-03-17 2004-03-17 Method for producing silicon particles Active JP4791697B2 (en)

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JP2004075521A JP4791697B2 (en) 2004-03-17 2004-03-17 Method for producing silicon particles
US10/592,864 US7850938B2 (en) 2004-03-17 2005-02-18 Silicon particles, silicon particle superlattice and method for producing the same
PCT/JP2005/002574 WO2005090234A1 (en) 2004-03-17 2005-02-18 Silicon particle, silicon particle superlattice and method for production thereof
CN 200580008256 CN1956920B (en) 2004-03-17 2005-02-18 Silicon particle, silicon particle superlattice and method for production thereof
US12/823,314 US8221881B2 (en) 2004-03-17 2010-06-25 Silicon particle, silicon particle superlattice and method for producing the same

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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102006024490A1 (en) * 2006-05-26 2007-11-29 Forschungszentrum Karlsruhe Gmbh Suspension used in the production of a semiconductor for printed circuit boards contains a silicon dioxide layer arranged on silicon particles
WO2009069416A1 (en) * 2007-11-29 2009-06-04 Konica Minolta Medical & Graphic, Inc. Semiconductor nanoparticle and method for producing the same
JP2013119489A (en) * 2011-12-06 2013-06-17 Bridgestone Corp Method for manufacturing silicon fine particle
WO2014123331A1 (en) * 2013-02-05 2014-08-14 주식회사 케이씨씨 Method for continuously preparing silicon nanoparticles, and anode active material for lithium secondary battery comprising same
WO2016052643A1 (en) * 2014-10-02 2016-04-07 山陽特殊製鋼株式会社 Powder for conductive fillers
JP2016072192A (en) * 2014-10-02 2016-05-09 山陽特殊製鋼株式会社 Powder for electrical conductive filler
JP2016110773A (en) * 2014-12-04 2016-06-20 山陽特殊製鋼株式会社 Powder for conductive filler

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CN103204507B (en) * 2013-04-07 2018-03-06 李绍光 A kind of Halogen silane thermal decomposition process for producing solar energy level silicon
CN104528727B (en) * 2014-12-24 2016-08-24 东北大学 A kind of porous silicon block materials with multistage directional hole and preparation method thereof

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JPH0672705A (en) * 1992-08-26 1994-03-15 Ube Ind Ltd Production of crystalline silicon superfine particle
JPH06279015A (en) * 1993-03-30 1994-10-04 Matsushita Electric Ind Co Ltd Production of ultrafine silicon particle

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US6585947B1 (en) 1999-10-22 2003-07-01 The Board Of Trustess Of The University Of Illinois Method for producing silicon nanoparticles

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JPH0672705A (en) * 1992-08-26 1994-03-15 Ube Ind Ltd Production of crystalline silicon superfine particle
JPH06279015A (en) * 1993-03-30 1994-10-04 Matsushita Electric Ind Co Ltd Production of ultrafine silicon particle

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102006024490A1 (en) * 2006-05-26 2007-11-29 Forschungszentrum Karlsruhe Gmbh Suspension used in the production of a semiconductor for printed circuit boards contains a silicon dioxide layer arranged on silicon particles
WO2009069416A1 (en) * 2007-11-29 2009-06-04 Konica Minolta Medical & Graphic, Inc. Semiconductor nanoparticle and method for producing the same
JP2013119489A (en) * 2011-12-06 2013-06-17 Bridgestone Corp Method for manufacturing silicon fine particle
WO2014123331A1 (en) * 2013-02-05 2014-08-14 주식회사 케이씨씨 Method for continuously preparing silicon nanoparticles, and anode active material for lithium secondary battery comprising same
KR20140100122A (en) * 2013-02-05 2014-08-14 주식회사 케이씨씨 Continuous manufacturing method for silicon nanoparticles and anode active materials containing the same for lithium ion battery
KR101583216B1 (en) * 2013-02-05 2016-01-07 주식회사 케이씨씨 Continuous manufacturing method for silicon nanoparticles and anode active materials containing the same for lithium ion battery
WO2016052643A1 (en) * 2014-10-02 2016-04-07 山陽特殊製鋼株式会社 Powder for conductive fillers
JP2016072192A (en) * 2014-10-02 2016-05-09 山陽特殊製鋼株式会社 Powder for electrical conductive filler
JP2016110773A (en) * 2014-12-04 2016-06-20 山陽特殊製鋼株式会社 Powder for conductive filler

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