JPS6343360B2 - - Google Patents
Info
- Publication number
- JPS6343360B2 JPS6343360B2 JP56173086A JP17308681A JPS6343360B2 JP S6343360 B2 JPS6343360 B2 JP S6343360B2 JP 56173086 A JP56173086 A JP 56173086A JP 17308681 A JP17308681 A JP 17308681A JP S6343360 B2 JPS6343360 B2 JP S6343360B2
- Authority
- JP
- Japan
- Prior art keywords
- silicon nitride
- fibrous
- powder
- nitrogen
- hydrogen
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 claims description 30
- 229910052581 Si3N4 Inorganic materials 0.000 claims description 29
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 13
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 12
- -1 nitrogen-containing silane compound Chemical class 0.000 claims description 11
- 239000001257 hydrogen Substances 0.000 claims description 9
- 229910052739 hydrogen Inorganic materials 0.000 claims description 9
- 229910000077 silane Inorganic materials 0.000 claims description 8
- 238000004519 manufacturing process Methods 0.000 claims description 7
- 238000000034 method Methods 0.000 claims description 7
- 229910052757 nitrogen Inorganic materials 0.000 claims description 6
- 239000002657 fibrous material Substances 0.000 claims 1
- 239000000843 powder Substances 0.000 description 13
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 12
- 239000007789 gas Substances 0.000 description 10
- 238000005979 thermal decomposition reaction Methods 0.000 description 6
- 229910021529 ammonia Inorganic materials 0.000 description 5
- 239000000460 chlorine Substances 0.000 description 5
- 239000013078 crystal Substances 0.000 description 4
- 239000000047 product Substances 0.000 description 4
- 229910052710 silicon Inorganic materials 0.000 description 4
- 239000010703 silicon Substances 0.000 description 4
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 3
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 3
- 239000006227 byproduct Substances 0.000 description 3
- 239000007795 chemical reaction product Substances 0.000 description 3
- 238000000635 electron micrograph Methods 0.000 description 3
- 238000009413 insulation Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 229910052750 molybdenum Inorganic materials 0.000 description 3
- 239000011733 molybdenum Substances 0.000 description 3
- VXEGSRKPIUDPQT-UHFFFAOYSA-N 4-[4-(4-methoxyphenyl)piperazin-1-yl]aniline Chemical compound C1=CC(OC)=CC=C1N1CCN(C=2C=CC(N)=CC=2)CC1 VXEGSRKPIUDPQT-UHFFFAOYSA-N 0.000 description 2
- NLXLAEXVIDQMFP-UHFFFAOYSA-N Ammonia chloride Chemical compound [NH4+].[Cl-] NLXLAEXVIDQMFP-UHFFFAOYSA-N 0.000 description 2
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 229910052801 chlorine Inorganic materials 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- RAABOESOVLLHRU-UHFFFAOYSA-N diazene Chemical compound N=N RAABOESOVLLHRU-UHFFFAOYSA-N 0.000 description 2
- 229910000071 diazene Inorganic materials 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 239000011812 mixed powder Substances 0.000 description 2
- 238000000634 powder X-ray diffraction Methods 0.000 description 2
- 239000011819 refractory material Substances 0.000 description 2
- 239000005049 silicon tetrachloride Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 235000019270 ammonium chloride Nutrition 0.000 description 1
- 229910021417 amorphous silicon Inorganic materials 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 239000000969 carrier Substances 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000006298 dechlorination reaction Methods 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 239000012772 electrical insulation material Substances 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 229910052736 halogen Inorganic materials 0.000 description 1
- 150000002367 halogens Chemical class 0.000 description 1
- 239000001307 helium Substances 0.000 description 1
- 229910052734 helium Inorganic materials 0.000 description 1
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 1
- 230000001771 impaired effect Effects 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 238000005121 nitriding Methods 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
- 238000000197 pyrolysis Methods 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 230000003014 reinforcing effect Effects 0.000 description 1
- 239000003566 sealing material Substances 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 239000012808 vapor phase Substances 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B25/00—Single-crystal growth by chemical reaction of reactive gases, e.g. chemical vapour-deposition growth
- C30B25/005—Growth of whiskers or needles
-
- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
- C30B29/10—Inorganic compounds or compositions
- C30B29/38—Nitrides
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Crystallography & Structural Chemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Inorganic Chemistry (AREA)
- Crystals, And After-Treatments Of Crystals (AREA)
Description
【発明の詳細な説明】
本発明は繊維状窒化珪素の製造法、更に詳しく
は含窒素シラン化合物を水素を主成分とする雰囲
気中で熱分解し、結晶性の良い繊維状α型窒化珪
素に転化せしめ高収量で製造する方法に関するも
のである。DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for producing fibrous silicon nitride, and more specifically, a method for producing fibrous silicon nitride by thermally decomposing a nitrogen-containing silane compound in an atmosphere containing hydrogen as a main component to produce fibrous α-type silicon nitride with good crystallinity. The present invention relates to a process for conversion and high yield production.
窒化珪素は耐熱性、化学的安定性、絶縁性、熱
伝導性等に優れているため高級耐火物、耐火材料
耐摩耗材料、電気絶縁材料などに使用されてい
る。また、窒化珪素の繊維状結晶は上記の特性以
外に機械的強度の点で優れており、各種複合材料
の強化基材の他、シール材、パツキング材、過
材、触媒担体等への応用が期待されている。 Silicon nitride has excellent heat resistance, chemical stability, insulation, thermal conductivity, etc., and is therefore used in high-grade refractories, refractory materials, wear-resistant materials, electrical insulation materials, and the like. In addition to the above-mentioned properties, silicon nitride fibrous crystals also have excellent mechanical strength, and can be used as reinforcing base materials for various composite materials, as well as sealing materials, packing materials, overmaterials, catalyst carriers, etc. It is expected.
繊維状窒化珪素の製造法としては、(1)シリコン
含有蒸気を炉内の基体と接触させ、これに窒化珪
素を析出させ、繊維状結晶を成長させる、いわゆ
る気相法、(2)シリコンの窒化の際に金属等を反応
系に添加し、融液の媒介により繊維状結晶を成長
させる方法等が知られているが、(1)の方法では大
量に窒化珪素繊維を生産することは非常に困難で
経済性に欠ける欠点があり、又、(2)の方法は大量
に高能率で繊維状窒化珪素を得ることができる
が、生成窒化珪素の純度が低いためその耐熱性、
絶縁性等がそこなわれる欠点がある。 Methods for producing fibrous silicon nitride include (1) a so-called vapor phase method in which silicon-containing vapor is brought into contact with a substrate in a furnace, and silicon nitride is precipitated thereto to grow fibrous crystals; (2) a method for producing silicon nitride; Methods such as adding metals to the reaction system during nitriding and growing fibrous crystals through the medium of the melt are known, but it is extremely difficult to produce silicon nitride fibers in large quantities using method (1). In addition, although method (2) can produce fibrous silicon nitride in large quantities with high efficiency, the purity of the produced silicon nitride is low, resulting in poor heat resistance.
There is a drawback that insulation properties etc. are impaired.
本発明者らは上記の点に鑑み、耐熱性、絶縁性
等に優れた高純度窒化珪素の繊維状結晶を容易か
つ高収量で得ることを目的として鋭意研究の結果
含窒素シラン化合物を水素を主成分とするガスの
流通下で熱分解する全く新規な製造法を見出し本
発明を完成した。 In view of the above points, the inventors of the present invention conducted intensive research to obtain fibrous crystals of high-purity silicon nitride with excellent heat resistance, insulation properties, etc. easily and in high yield. We discovered a completely new production method that involves thermal decomposition under the flow of gas, which is the main component, and completed the present invention.
以下本発明を詳細に説明する。本発明の製造法
は含窒素シラン化合物を、水素を主成分とするガ
スの流通下で加熱分解することを特徴とする。 The present invention will be explained in detail below. The production method of the present invention is characterized in that a nitrogen-containing silane compound is thermally decomposed under the flow of a gas containing hydrogen as a main component.
本発明に使用する含窒素シラン化合物とはハロ
ゲン化珪素とアンモニアとの反応生成物である、
シリコンジイミド（Si（NH）2）とハロゲン化ア
ンモニウムの混合物を液体アンモニアで洗浄して
得たSi（NH）2、或いはシリコンジイミド、塩化
アンモニウムを窒素或いはアンモニア中で加熱し
て得た分解生成物、即ちSi2N3H、及び非晶質窒
化珪素粉末等である。 The nitrogen-containing silane compound used in the present invention is a reaction product of silicon halide and ammonia.
Si(NH) 2 obtained by washing a mixture of silicon diimide (Si(NH) 2 ) and ammonium halide with liquid ammonia, or a decomposition product obtained by heating silicon diimide and ammonium chloride in nitrogen or ammonia. , that is, Si 2 N 3 H, amorphous silicon nitride powder, etc.
本発明においては、上述したような含窒素シラ
ン化合物を水素を主成分とするガスの流通下で熱
分解する。更に言えば繊維状窒化珪素を収率よく
合成するためには熱分解雰囲気中の水素ガスは少
なくとも体積にして80％以上を含むことを要す
る。上記の条件が満たされる限りにおいては、加
熱雰囲気中には水素以外に窒素、アルゴン、ヘリ
ウム等の不活性ガス、塩素等のハロゲンガスを含
んでいても何ら支障はないが、特に窒素に関して
はその含有量は10容量％以下でなければならな
い。その理由としては、10容量％を越える窒素を
含むと繊維状窒化珪素の他に粒状の窒化珪素が副
生するためである。 In the present invention, the nitrogen-containing silane compound as described above is thermally decomposed under the flow of a gas containing hydrogen as a main component. Furthermore, in order to synthesize fibrous silicon nitride with good yield, the pyrolysis atmosphere must contain at least 80% or more hydrogen gas by volume. As long as the above conditions are met, there is no problem even if the heating atmosphere contains inert gases such as nitrogen, argon, helium, etc., and halogen gases such as chlorine in addition to hydrogen. The content must be less than 10% by volume. The reason for this is that if more than 10% by volume of nitrogen is contained, granular silicon nitride is produced as a by-product in addition to fibrous silicon nitride.
熱分解の際、流通させるガスの流通量は特に限
定するものではないが、例えば熱分解に際して窒
素、塩素等のガスを発生する含窒素シラン化合物
を原料として使用する場合は上記のような発生ガ
スによつて雰囲気中の水素濃度が低下せぬように
ガスの流通量を増加するなどして制御する必要が
ある。 During thermal decomposition, the flow rate of the gas to be circulated is not particularly limited, but for example, when a nitrogen-containing silane compound that generates gases such as nitrogen and chlorine during thermal decomposition is used as a raw material, the gas generated as above is used. Therefore, it is necessary to control the hydrogen concentration in the atmosphere by increasing the flow rate of the gas so as not to reduce the hydrogen concentration in the atmosphere.
本発明において含窒素シラン化合物を上述のよ
うな雰囲気中で熱分解する温度は1300℃〜1400℃
でなければならない。熱分解温度が1300℃未満の
場合は含窒素シラン化合物が充分分解・結晶化せ
ず、所望の繊維状窒化珪素を得ることができな
い。また、熱分解温度が1400℃を越えると粒状の
窒化珪素が副生するので、繊維状窒化珪素を収率
よく得ることができない。 In the present invention, the temperature at which the nitrogen-containing silane compound is thermally decomposed in the above atmosphere is 1300°C to 1400°C.
Must. If the thermal decomposition temperature is less than 1300°C, the nitrogen-containing silane compound will not be sufficiently decomposed and crystallized, making it impossible to obtain the desired fibrous silicon nitride. Furthermore, if the thermal decomposition temperature exceeds 1400°C, granular silicon nitride is produced as a by-product, making it impossible to obtain fibrous silicon nitride in good yield.
上述のような熱分解反応が完了するのに要する
時間は通常0.5〜１時間であり、１時間以上とす
れば充分である。 The time required to complete the thermal decomposition reaction as described above is usually 0.5 to 1 hour, and 1 hour or more is sufficient.
以上、本発明について説明したが、本発明は高
純度の繊維状窒化珪素を容易に大量に製造できる
点で有用である。 The present invention has been described above, and the present invention is useful in that high purity fibrous silicon nitride can be easily produced in large quantities.
以下実施例により本発明を更に詳述する。 The present invention will be explained in more detail with reference to Examples below.
実施例 １
四塩化珪素とアンモニアを反応させて得た反応
生成物であるSi（NH）2、NH4Clの混合粉末を石
英で形成された管状炉内に仕込み、アンモニア気
流中1000℃の温度下で10時間保持して脱塩素し
て、白色の非晶質粉末を得た。化学分析によりこ
の粉末の組成はSi2N3Hであることがわかつた。Example 1 A mixed powder of Si(NH) 2 and NH 4 Cl, which is a reaction product obtained by reacting silicon tetrachloride with ammonia, was placed in a tubular furnace made of quartz and heated at a temperature of 1000°C in an ammonia stream. The mixture was kept under vacuum for 10 hours for dechlorination to obtain a white amorphous powder. Chemical analysis revealed that the composition of this powder was Si 2 N 3 H.
次に上記のSi2N3H粉末5gをモリブデン製ボー
トに充填し、あらかじめ水素ガスを満した管状炉
に装入して水素ガス（99.9vol％）を毎分300mlの
割合で管状炉内に流通しながら1350℃に加熱し
た。この状態で１時間保持することによつてフエ
ルト状の白色粉体を得た。Ｘ線粉末回折の結果、
この粉末はα型窒化珪素であることがわかつた。
またこの粉末の電子顕微鏡写真（3000倍）を第１
図に示した。この写真に見るように、生成物のほ
とんどは径が約0.1μm、長さが数μmの繊維状又
は針状の窒化珪素であつた。 Next, 5g of the above Si 2 N 3 H powder was filled into a molybdenum boat and charged into a tube furnace previously filled with hydrogen gas, and hydrogen gas (99.9vol%) was fed into the tube furnace at a rate of 300ml per minute. It was heated to 1350°C while flowing. By maintaining this state for 1 hour, a felt-like white powder was obtained. As a result of X-ray powder diffraction,
This powder was found to be α-type silicon nitride.
In addition, the first electron micrograph (3000x) of this powder is
Shown in the figure. As seen in this photo, most of the products were fibrous or acicular silicon nitride with a diameter of about 0.1 μm and a length of several μm.
実施例 ２
四塩化珪素とアンモニアを反応させて得た反応
生成物であるSi（NH）2、NH4Clの混合粉末を−
70℃の液体アンモニアで洗浄し、副生した
NH4Clを除去しSi（NH）2を単離した。Example 2 A mixed powder of Si(NH) 2 and NH 4 Cl, which is a reaction product obtained by reacting silicon tetrachloride with ammonia, was
Cleaned with liquid ammonia at 70℃ and produced as a by-product
NH 4 Cl was removed and Si(NH) 2 was isolated.
次に上記のSi（NH）2粉末5gをモリブデン製ボ
ートに充填しあらかじめ水素ガスを満した管状炉
に装入し、水素含有ガス（H2：90vol％）を毎分
300mlの割合で管状炉内に流通しながら1400℃に
加熱した。この状態で１時間保持することによつ
てフエルト状の白色粉体を得た。Ｘ線粉末回折の
結果この粉末はα型窒化珪素であることがわかつ
た。また電子顕微鏡による観察の結果、生成物の
ほとんどが径約0.1μm、長さが数μmの繊維状又
は針状の窒化珪素であつた。 Next, 5 g of the above Si(NH) 2 powder was filled into a molybdenum boat and charged into a tube furnace filled with hydrogen gas in advance, and hydrogen-containing gas (H 2 : 90 vol%) was supplied every minute.
It was heated to 1400°C while flowing through a tube furnace at a rate of 300ml. By maintaining this state for 1 hour, a felt-like white powder was obtained. As a result of X-ray powder diffraction, this powder was found to be α-type silicon nitride. Further, as a result of observation using an electron microscope, most of the products were fibrous or needle-like silicon nitride with a diameter of about 0.1 μm and a length of several μm.
比較例 １
実施例１と同様にして得たSi2N3H粉末5gをモ
リブデン製ボートに充填、あらかじめ１：１の水
素、窒素混合ガスを毎分300mlの割合で管状炉内
に流通しながら管状炉によつて1350℃に加熱し
た。この状態で１時間保持することにより窒化珪
素粉末を得た。得られた窒化珪素粉末の電子顕微
鏡写真（10000倍）を第２図に示した。この写真
に見るように生成物は繊維状又は針状の窒化珪素
の他に粒状の窒化珪素を含んでいた。Comparative Example 1 5 g of Si 2 N 3 H powder obtained in the same manner as in Example 1 was filled into a molybdenum boat, and a 1:1 hydrogen/nitrogen mixed gas was passed through the tube furnace at a rate of 300 ml per minute. It was heated to 1350°C by a tube furnace. By maintaining this state for 1 hour, silicon nitride powder was obtained. An electron micrograph (10,000 times magnification) of the obtained silicon nitride powder is shown in FIG. As seen in this photograph, the product contained granular silicon nitride in addition to fibrous or acicular silicon nitride.
第１図及び第２図は本発明の実施例１及び比較
例１で得た窒化珪素の電子顕微鏡写真を夫々示
す。
FIGS. 1 and 2 show electron micrographs of silicon nitride obtained in Example 1 of the present invention and Comparative Example 1, respectively.
Claims (1)
を含み、窒素含有量が０〜10容量％である雰囲気
下で、1300℃〜1400℃で１時間以上加熱分解する
ことを特徴とする繊維状窒化珪素の製造方法。1. A fibrous material characterized by thermally decomposing a nitrogen-containing silane compound at 1300°C to 1400°C for 1 hour or more in an atmosphere containing 80% by volume or more hydrogen and a nitrogen content of 0 to 10% by volume. Method for manufacturing silicon nitride.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP56173086A JPS5874598A (en) | 1981-10-30 | 1981-10-30 | Manufacture of fibrous silicon nitride |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP56173086A JPS5874598A (en) | 1981-10-30 | 1981-10-30 | Manufacture of fibrous silicon nitride |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5874598A JPS5874598A (en) | 1983-05-06 |
| JPS6343360B2 true JPS6343360B2 (en) | 1988-08-30 |
Family
ID=15953938
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP56173086A Granted JPS5874598A (en) | 1981-10-30 | 1981-10-30 | Manufacture of fibrous silicon nitride |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5874598A (en) |
-
1981
- 1981-10-30 JP JP56173086A patent/JPS5874598A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5874598A (en) | 1983-05-06 |
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