JPH0789764A - Silicon carbide heating element - Google Patents
Silicon carbide heating elementInfo
- Publication number
- JPH0789764A JPH0789764A JP5257760A JP25776093A JPH0789764A JP H0789764 A JPH0789764 A JP H0789764A JP 5257760 A JP5257760 A JP 5257760A JP 25776093 A JP25776093 A JP 25776093A JP H0789764 A JPH0789764 A JP H0789764A
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- silicon carbide
- heating element
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- temperature
- resistance
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Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、炭化珪素質の電気抵抗
発熱体に係り、詳しくは常温から約８００℃の温度域に
おける比抵抗の下降変動が小さい炭化珪素発熱体に関す
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a silicon carbide-based electric resistance heating element, and more particularly to a silicon carbide heating element with a small variation in the decrease in resistivity in the temperature range from room temperature to about 800 ° C.
【０００２】[0002]
【従来の技術】炭化珪素は、良電導性の化合物半導体で
あって、材質的に優れた耐熱性および化学的安定性を具
備していることから、高温電気炉用等の通電発熱体とし
て古くから有用されている。2. Description of the Related Art Silicon carbide is a compound semiconductor having a good electric conductivity, and has excellent heat resistance and chemical stability in terms of material. Therefore, it has long been used as an electric heating element for high temperature electric furnaces. Has been useful from.
【０００３】一般に炭化珪素には、通電発熱による温度
上昇に伴って比抵抗が急激に降下し、約８００℃付近を
極小として上昇に転じて最高使用可能の温度域まで持続
するという抵抗変動を示す性癖がある。この理由は、炭
化珪素は半導体であるため不純物準位から伝導帯へ励起
できる伝導電子の数が温度上昇に伴って増大し、この挙
動によって常温から約８００℃までは抵抗が低下する
が、約８００℃以降は格子の熱振動により伝導電子の移
動度が低下するため抵抗が若干上昇傾向を示すことに基
づくものと解釈されている。しかし、このように常温〜
約８００℃の範囲で比抵抗の温度変化が負特性を示す
と、発熱体にした場合に電流急増による熱暴走を招き易
く、またこの変化率が大きいものは温度制御が極めて困
難となる。In general, in silicon carbide, the specific resistance sharply drops as the temperature rises due to the heat generated by energization, and changes to increase with a minimum at around 800 ° C. and continues to the maximum usable temperature range. I have a propensity. The reason for this is that since silicon carbide is a semiconductor, the number of conduction electrons that can be excited from the impurity level to the conduction band increases as the temperature rises, and this behavior reduces the resistance from room temperature to about 800 ° C. After 800 ° C., it is interpreted that the resistance tends to increase slightly because the mobility of conduction electrons decreases due to thermal vibration of the lattice. However, at room temperature
When the temperature change of the specific resistance shows a negative characteristic in the range of about 800 ° C., thermal runaway is apt to occur due to a rapid increase in current when used as a heating element, and if the rate of change is large, temperature control becomes extremely difficult.
【０００４】このため、炭化珪素発熱体における抵抗の
負特性を減少させる目的で従来から種々の試みが提案さ
れている。例えば特公昭５１−４５３３９号公報には、
炭化珪素焼結体をケイ石、炭素、窒化珪素を含む混合粉
末で包み二次焼成する方法が開示されている。特公昭６
１−５６１８７号公報には、炭化珪素粉末にホウ素と炭
素などを添加し、真空中で１次焼成したのち１〜２００
気圧の窒素雰囲気中で２次焼結する方法が示されてい
る。特開昭５８−２０９０８４号公報には炭化珪素に炭
化ジルコニウムや硼化ジルコニウムを添加して焼結した
抵抗温度係数が正の直線形ヒータ材が、また特開昭５９
−１１１２８９号公報には炭化珪素ウイスカとモリブデ
ン粉末および炭素粉末を混合し焼結した所望の固有抵抗
をもつ発熱体が提案されている。Therefore, various attempts have heretofore been proposed for the purpose of reducing the negative resistance characteristic of the silicon carbide heating element. For example, in Japanese Patent Publication No. 51-45339,
A method of wrapping a silicon carbide sintered body with a mixed powder containing silica stone, carbon, and silicon nitride and performing secondary firing is disclosed. Tokusho Sho 6
In JP-A 1-56187, boron and carbon are added to silicon carbide powder, and primary firing is performed in a vacuum, and then 1 to 200.
A method of performing secondary sintering in a nitrogen atmosphere at atmospheric pressure is shown. JP-A-58-209084 discloses a linear heater material having a positive temperature coefficient of resistance, which is obtained by adding zirconium carbide or zirconium boride to silicon carbide and sintering.
Japanese Patent Laid-Open No. -1112989 proposes a heating element having a desired specific resistance obtained by mixing silicon carbide whiskers with molybdenum powder and carbon powder and sintering them.
【０００５】[0005]
【発明が解決しようとする課題】本発明者らは、従来技
術では注目されていなかった炭化珪素の結晶相と抵抗の
温度変化との関係について多くの研究を重ねたところ、
特定量のβ−ＳｉＣ結晶を含む窒素固溶型の炭化珪素は
発熱体とした場合に比抵抗の負特性を効果的に減少し得
ることを確認した。DISCLOSURE OF INVENTION Problems to be Solved by the Invention The present inventors have conducted many studies on the relationship between the crystal phase of silicon carbide and the temperature change of resistance, which has not received attention in the prior art.
It was confirmed that nitrogen solid solution type silicon carbide containing a specific amount of β-SiC crystal can effectively reduce the negative characteristic of the resistivity when used as a heating element.
【０００６】本発明は前記の知見に基づいて開発された
もので、その目的は、常温から約８００℃範囲における
比抵抗の下降が少ない安定した発熱性能を有する炭化珪
素発熱体を提供することにある。The present invention was developed on the basis of the above findings, and an object thereof is to provide a silicon carbide heating element having a stable heating performance with a small decrease in the specific resistance in the range of room temperature to about 800 ° C. is there.
【０００７】[0007]
【課題を解決するための手段】上記の目的を達成するた
めの本発明による炭化珪素発熱体は、窒素が固溶したＮ
型半導体であって、β−ＳｉＣ結晶粒を少なくとも１０
％含有する炭化珪素質焼結体からなることを構成上の特
徴とする。The silicon carbide heating element according to the present invention for attaining the above object is formed of N dissolved in nitrogen.
Type semiconductor having at least 10 β-SiC crystal grains.
The constitutional feature is that it is made of a silicon carbide-based sintered body containing 100% by weight.
【０００８】炭化珪素は化合物半導体であるが、そのバ
ンドギャップは２〜３ｅＶと非常に広いため抵抗を通電
発熱可能なレベルまで下げるためには III族元素または
Ｖ族元素を固溶させ、ドナーまたはアクセプター準位を
形成させる必要がある。炭化珪素が常温から約８００℃
の範囲において示す抵抗の負の変化率は固溶させるドナ
ーまたはアクセプター準位に依存し、ドナー準位と伝導
帯またはアクセプター準位と価電子帯とのエネルギーギ
ャップが大きいほど比抵抗の温度変化は大きくなる。炭
化珪素に固溶可能な III族またはＶ族元素としてはホウ
素、窒素、アルミニウム、リンなどがあるが、この中で
も窒素固溶により形成されたドナー準位が最も伝導帯と
のエネルギーギャップが小さい。本発明の炭化珪素発熱
体を構成する窒素を固溶したＮ型半導体は、抵抗の温度
変化を小さくするための前提条件となる。Silicon carbide is a compound semiconductor, but its bandgap is as wide as 2 to 3 eV. Therefore, in order to reduce the resistance to a level at which heat can be generated by energization, a group III element or a group V element is solid-dissolved and a donor or It is necessary to form an acceptor level. Silicon carbide is about 800 ℃ from room temperature
The negative rate of change in resistance shown in the range of depends on the donor or acceptor level to be solid-solved, and the larger the energy gap between the donor level and the conduction band or the acceptor level and the valence band, the more the temperature change of the specific resistance. growing. Group III or V elements that can be solid-dissolved in silicon carbide include boron, nitrogen, aluminum, and phosphorus. Among them, the donor level formed by solid solution of nitrogen has the smallest energy gap with the conduction band. The N-type semiconductor containing nitrogen as a solid solution which constitutes the silicon carbide heating element of the present invention is a prerequisite for reducing the temperature change of resistance.
【０００９】炭化珪素の結晶には数多くの多形が存在す
るが、これを大別すると立方晶のβ−ＳｉＣと六方晶、
菱面体のα−ＳｉＣに分類される。窒素固溶によるドナ
ー準位はこの結晶形に依存し、β型（３Ｃ）の準位は
０．０３〜０．０５ｅＶと小さいのに対して、α型（６
Ｈ）の準位は０．０７〜０．１ｅＶと大きい。つまりβ
−ＳｉＣの結晶系で発熱体を構成すれば抵抗の温度変化
を小さくすることが可能となる。本発明の炭化珪素発熱
体は、β−ＳｉＣ結晶粒を少なくとも１０％含有してお
り、この組成がβ−ＳｉＣ結晶粒を経由した電気伝導を
支配的にして抵抗の温度変化を低減させ、温度制御を容
易にするために効果的に機能する。しかしβ−ＳｉＣ結
晶粒の含有率が１０％未満の組成になると、他の結晶相
による導電が支配的となって、抵抗の温度変化を小さく
することができなくなる。There are many polymorphs in silicon carbide crystals, which are roughly classified into cubic β-SiC and hexagonal crystals.
It is classified as a rhombohedral α-SiC. The donor level due to the solid solution of nitrogen depends on this crystal form, and the level of β-type (3C) is as small as 0.03 to 0.05 eV, while that of α-type (6
The level of H) is as large as 0.07 to 0.1 eV. That is β
If the heating element is made of a -SiC crystal system, the temperature change of resistance can be reduced. The silicon carbide heating element of the present invention contains at least 10% of β-SiC crystal grains, and this composition predominantly conducts electric conduction via the β-SiC crystal grains to reduce the temperature change of the resistance. Works effectively for ease of control. However, if the composition ratio of β-SiC crystal grains is less than 10%, the conductivity due to other crystal phases becomes dominant and the temperature change of resistance cannot be reduced.
【００１０】本発明の炭化珪素発熱体は、上記の組成性
状を有する炭化珪素質焼結体からなる。該炭化珪素質焼
結体は、β−ＳｉＣ結晶系を主体とする炭化珪素粉末を
原料とし、これを常法により所望の形状に成形したのち
窒素雰囲気に保持された加熱炉中で焼結処理することに
よって製造することができる。炭化珪素原料粉の結晶系
はβ型を主体とするが、焼結条件によってはβ型からα
型への転移あるいはα型からβ型への逆転移が生じるた
め、この現象を配慮して原料系組成を設定する必要があ
る。炭化珪素原料には、所望によりホウ素や炭素などの
成分を添加することができ、反応によりβ−ＳｉＣが生
成するような成分系を介在させることもできる。焼結の
方法には特に限定はなく、昇華再結晶法や反応結晶法、
焼結助剤を添加した常圧焼結などいずれの方法であって
もよい。焼結温度は２０００〜２２００℃の範囲に設定
することが好ましく、２２００℃を越えるとβ−ＳｉＣ
からα−ＳｉＣへの結晶相転移が大きくなってβ−Ｓｉ
Ｃ結晶粒１０％以上の含有率が確保できないことがあ
る。The silicon carbide heating element of the present invention is composed of a silicon carbide based sintered body having the above compositional characteristics. The silicon carbide-based sintered body is made of silicon carbide powder having a β-SiC crystal system as a main material, shaped into a desired shape by an ordinary method, and then sintered in a heating furnace kept in a nitrogen atmosphere. Can be manufactured. The crystal system of the silicon carbide raw material powder is mainly β type, but depending on the sintering conditions,
Since the transition to the mold or the reverse transition from the α type to the β type occurs, it is necessary to set the raw material system composition in consideration of this phenomenon. If desired, components such as boron and carbon can be added to the silicon carbide raw material, and a component system in which β-SiC is produced by the reaction can be interposed. The sintering method is not particularly limited, and includes a sublimation recrystallization method and a reaction crystal method,
Any method such as atmospheric pressure sintering in which a sintering aid is added may be used. The sintering temperature is preferably set in the range of 2000 to 2200 ° C, and when it exceeds 2200 ° C, β-SiC
Crystal phase transition from α to α-SiC becomes large and β-Si
In some cases, the content of C crystal grains of 10% or more cannot be secured.
【００１１】[0011]
【作用】本発明の炭化珪素発熱体によれば、窒素による
置換固溶したＮ型半導体の組成が伝導帯とのエネルギー
ギャップを最小にするドナー準位を形成し、抵抗の温度
変化幅を縮小させる前提的な機能を果たす。これに加え
てβ−ＳｉＣ結晶粒を１０％以上含む結晶組成系が、通
電時においてβ−ＳｉＣ結晶相を経由する電気伝導ルー
トを支配的とし、この作用が前記した前提的機能に相乗
して抵抗の温度変化を効果的に低減化すると共に、温度
制御の容易な発熱体性能を付与する。したがって、常温
から約８００℃の温度域において生じる抵抗の負特性は
改善され、広い温度範囲において常に安定した比抵抗を
示す高性能の炭化珪素発熱体を供給することが可能とな
る。According to the silicon carbide heating element of the present invention, the composition of the N-type semiconductor that is solid-dissolved by substitution with nitrogen forms a donor level that minimizes the energy gap with the conduction band and reduces the temperature change width of the resistance. Performs a pre-requisite function. In addition to this, a crystal composition system containing 10% or more of β-SiC crystal grains dominates the electric conduction route via the β-SiC crystal phase during energization, and this action synergizes with the above-mentioned presupposed function. It effectively reduces the temperature change of the resistance and imparts the performance of a heating element whose temperature can be easily controlled. Therefore, the negative characteristic of resistance that occurs in the temperature range from room temperature to about 800 ° C. is improved, and it becomes possible to supply a high-performance silicon carbide heating element that always exhibits stable specific resistance in a wide temperature range.
【００１２】[0012]
【実施例】以下、本発明の実施例を比較例と対比しなが
ら詳細に説明する。EXAMPLES Examples of the present invention will be described in detail below in comparison with comparative examples.
【００１３】実施例１ 平均粒子径１μm 以下のβ−ＳｉＣ粉末〔イビデン
（株）製、商品名“ベータランダム”〕にバインダーお
よび水を加え、常法により直径１５mm、長さ５０mmの円
柱状に押出成形した。成形体を乾燥したのち、窒素雰囲
気１．３atm の加熱炉内に入れ、２０００℃の温度で１
時間焼結して炭化珪素質焼結体を得た。得られた炭化珪
素質焼結体の窒素固溶量は０．０５％であり、ＰＮ判別
試験をおこなったところＮ型半導体であることが確認さ
れた。また、β−ＳｉＣ結晶粒の含有率を粉末Ｘ線回折
法により得られる回折プロファイルを河村の式（窯業協
会誌，87, 〔11〕,576-82,1979) に従って解析する方法
で定量したところ、８０％であった。これは原料として
用いたβ−ＳｉＣ結晶粒の一部が焼結時に高温安定型で
あるα−ＳｉＣに転移したためである。Example 1 A binder and water were added to β-SiC powder having an average particle size of 1 μm or less [trade name “Beta Random” manufactured by Ibiden Co., Ltd.], and a columnar shape having a diameter of 15 mm and a length of 50 mm was prepared by a conventional method. Extruded. After the molded product is dried, it is placed in a heating furnace with a nitrogen atmosphere of 1.3 atm and heated at 2000 ° C. for 1 hour.
Sintering was carried out for a time to obtain a silicon carbide based sintered body. The nitrogen solid solution amount of the obtained silicon carbide sintered body was 0.05%, and it was confirmed by a PN discrimination test that it was an N-type semiconductor. In addition, the content of β-SiC crystal grains was quantified by the method of analyzing the diffraction profile obtained by the powder X-ray diffraction method according to Kawamura's formula (Chemical Industry Association Journal, 87, [11], 576-82, 1979). , 80%. This is because a part of the β-SiC crystal grains used as the raw material was transformed into α-SiC which is a high temperature stable type during sintering.
【００１４】上記の炭化珪素質焼結体を発熱体とし、通
電発熱させて比抵抗の温度変化を測定した。その結果を
図１に示したが、常温から約８００℃での抵抗の下降変
動は殆ど認められなかった。また、全体としての発熱特
性を評価した結果を発熱体組成と対比させて表１に示し
た。The above-mentioned silicon carbide based sintered body was used as a heating element and was heated by energization to measure the temperature change of the specific resistance. The results are shown in FIG. 1, but almost no change in resistance drop was observed from room temperature to about 800 ° C. In addition, the results of evaluating the heat generation characteristics as a whole are shown in Table 1 in comparison with the composition of the heating element.
【００１５】実施例２ 焼結温度を２２００℃に変えたほかは全て実施例１と同
一条件により炭化珪素質焼結体を作製した。この炭化珪
素焼結体の窒素固溶量は０．０３％であり、Ｎ型を呈す
るものであった。β−ＳｉＣ結晶粒の含有率は１５％で
あったが、透過型電子顕微鏡にて組織観察したところβ
−ＳｉＣとみられる針状結晶により導電経路が形成され
ていることが確認された。実施例１と同様に発熱体とし
ての試験評価をおこない、結果をそれぞれ図１および表
１に併載した。Example 2 A silicon carbide sintered body was produced under the same conditions as in Example 1 except that the sintering temperature was changed to 2200 ° C. The nitrogen solid solution amount of this silicon carbide sintered body was 0.03%, and it was N type. The content of β-SiC crystal grains was 15%, but when the structure was observed with a transmission electron microscope, β
It was confirmed that the conductive path was formed by needle-like crystals that were considered to be —SiC. Test evaluation as a heating element was performed in the same manner as in Example 1, and the results are shown in FIG. 1 and Table 1, respectively.
【００１６】比較例１ 焼結温度を２３００℃に高めたほかは、全て実施例１と
同一条件により炭化珪素質焼結体を作製した。この炭化
珪素質焼結体の窒素固溶量は０．０２％で、Ｎ型半導体
であったが、高温焼結のためβ型結晶粒の大半がα型へ
相転移した関係でβ−ＳｉＣ結晶粒の含有率は５％と少
なかった。発熱体としての試験評価結果を図１および表
１に併載したが、比抵抗の温度変化は比較的大きく、ま
た発熱分布を不良で発熱体には不適であった。Comparative Example 1 A silicon carbide based sintered body was produced under the same conditions as in Example 1 except that the sintering temperature was raised to 2300 ° C. This silicon carbide sintered body had a nitrogen solid solution amount of 0.02% and was an N-type semiconductor. However, due to the high temperature sintering, most of β-type crystal grains were phase-transformed to α-type, so β-SiC The content of crystal grains was as small as 5%. The results of the test evaluation as a heating element are also shown in FIG. 1 and Table 1, but the temperature change of the specific resistance was relatively large, and the heat generation distribution was poor, which was not suitable for the heating element.
【００１７】比較例２ 実施例１と同一の成形体を、アルゴン雰囲気１．３atm
の加熱炉中で２０００℃の温度で焼結した。得られた炭
化珪素質焼結体に占めるβ−ＳｉＣ結晶粒の含有率は８
０％であったが、固溶窒素は検出されなかった。その発
熱体としての試験評価結果を図１および表１に併載し
た。この場合の比抵抗の温度変化は高温域で直線的に降
下し、また発熱状態も不良であった。COMPARATIVE EXAMPLE 2 The same molded body as in Example 1 was used in an argon atmosphere of 1.3 atm.
Sintered at a temperature of 2000 ° C. The content rate of β-SiC crystal grains in the obtained silicon carbide sintered body was 8
Although it was 0%, solute nitrogen was not detected. The test evaluation results as the heating element are also shown in FIG. 1 and Table 1. The temperature change of the specific resistance in this case dropped linearly in the high temperature region, and the heat generation state was also poor.
【００１８】比較例３ 平均粒径１μm 以下のα−ＳｉＣ粉末〔大平洋ランダム
（株）製、ＧＭＦ〕を原料として、実施例１と同一操作
により成形、焼結して炭化珪素質焼結体を作製した。得
られた炭化珪素質焼結体にはβ−ＳｉＣ結晶が検出され
なかった。発熱体としての試験評価結果を図１および表
１に併載したが、比抵抗の温度変化は大きく、発熱分布
も不良であった。Comparative Example 3 An α-SiC powder having an average particle diameter of 1 μm or less [GMF manufactured by Taiheiyo Random Co., Ltd.] was used as a raw material and molded and sintered by the same operation as in Example 1 to obtain a silicon carbide sintered body. Was produced. No β-SiC crystal was detected in the obtained silicon carbide sintered body. The test evaluation results as a heating element are also shown in FIG. 1 and Table 1, but the temperature change of the specific resistance was large and the heat generation distribution was also poor.
【００１９】実施例３ 比較例３の焼結処理を、窒素雰囲気圧３０atm の加熱炉
中で２０００℃の温度で１時間加熱する条件でおこない
炭化珪素質焼結体を得た。この例では、炭化珪素焼結体
は窒素固溶量が０．０８％のＮ型半導体で、β−ＳｉＣ
結晶含有率は２５％であった。これは窒素雰囲気圧が高
圧であるためα型からβ型へ逆転移したものと推測され
た。発熱体としての試験評価も図１および表１に併載し
たように良好な結果を示した。Example 3 The sintering treatment of Comparative Example 3 was carried out under the conditions of heating at a temperature of 2000 ° C. for 1 hour in a heating furnace having a nitrogen atmosphere pressure of 30 atm to obtain a silicon carbide based sintered body. In this example, the silicon carbide sintered body is an N-type semiconductor with a nitrogen solid solution amount of 0.08%, and is made of β-SiC.
The crystal content was 25%. It was speculated that this was due to a high nitrogen atmosphere pressure, which caused a reverse transition from α-type to β-type. The test evaluation as a heating element also showed good results as shown in FIG. 1 and Table 1.
【００２０】実施例４ 平均粒径１μm 以下のβ−ＳｉＣ粉末〔イビデン
（株）、商品名“ベータランダム”〕に非晶質ホウ素粉
末〔Ｈ．Ｃシュタルク製〕０．２重量％およびカーボン
ブラック〔東海カーボン（株）製〕２重量％を添加混合
し、ＣＩＰ成形した。この成形体をアルゴン雰囲気中１
９００℃で予備焼結し、ついで窒素雰囲気に保持された
加熱炉に移し２０００℃の温度で焼結処理した。得られ
た炭化珪素質焼結体は、窒素固溶量０．０４％のＮ型半
導体で、β−ＳｉＣ結晶粒の含有率は６０％であった。
図１および表１に発熱体としての試験評価を併載した
が、良好な結果を示した。Example 4 β-SiC powder having an average particle size of 1 μm or less [Ibiden Co., Ltd., trade name “Beta random”] was added to amorphous boron powder [H. C Stark] 0.2 wt% and carbon black [Tokai Carbon Co., Ltd.] 2 wt% were added and mixed, and CIP molding was performed. This molded body 1 in an argon atmosphere
It was pre-sintered at 900 ° C., then transferred to a heating furnace kept in a nitrogen atmosphere and sintered at a temperature of 2000 ° C. The obtained silicon carbide sintered body was an N-type semiconductor with a nitrogen solid solution amount of 0.04%, and the β-SiC crystal grain content was 60%.
The test evaluation as a heating element is also shown in FIG. 1 and Table 1, and a good result was shown.
【００２１】実施例５ 平均粒径５μm のα−ＳｉＣ粉末〔大平洋ランダム
（株）製、ＧＭＦ〕にカーボンブラック〔東海カーボン
（株）製〕３０重量％を添加混合し、成形後、Ｓｉ塊中
に包埋した状態で窒素雰囲気中２０００℃で反応焼結し
た。得られた炭化珪素質焼結体の窒素固溶量は０．０８
％であり、またＣとＳｉの反応により生成されたＳｉＣ
がβ型であった関係で原料がα−ＳｉＣ粉末であるにも
拘わらずβ−ＳｉＣ結晶粒の含有率は４０％であった。
発熱体としての試験評価結果は、図１および表１に併載
したように極めて良好なものであった。Example 5 30% by weight of carbon black [Tokai Carbon Co., Ltd.] was added to and mixed with α-SiC powder having an average particle size of 5 μm [GMF manufactured by Taiheiyo Random Co., Ltd.], and molded into a Si mass. It was reaction-sintered at 2000 ° C. in a nitrogen atmosphere while being embedded therein. The amount of nitrogen solid solution of the obtained silicon carbide sintered body was 0.08.
%, And SiC produced by the reaction of C and Si
However, the content of β-SiC crystal grains was 40% even though the raw material was α-SiC powder.
The test evaluation results for the heating element were extremely good as shown in FIG. 1 and Table 1.
【００２２】[0022]
【表１】 [Table 1]
【００２３】[0023]
【発明の効果】以上のとおり、本発明によれば炭化珪素
発熱体を窒素固溶したＮ型半導体であって、β−ＳｉＣ
結晶粒が少なくとも１０％含有する炭化珪素質焼結体で
構成することにより、常温から約８００℃範囲における
負の抵抗変動を効果的に減少させ、安定した発熱特性を
付与することができる。したがって、温度制御が容易な
高品質の炭化珪素発熱体を供給することが可能となる。As described above, according to the present invention, an N-type semiconductor in which a silicon carbide heating element is solid-dissolved in nitrogen, wherein β-SiC is used.
By using a silicon carbide-based sintered body containing at least 10% of crystal grains, it is possible to effectively reduce the negative resistance variation in the range of normal temperature to about 800 ° C., and to provide stable heat generation characteristics. Therefore, it becomes possible to supply a high-quality silicon carbide heating element whose temperature is easily controlled.
【図１】実施例および比較例における温度と比抵抗の関
係を示したグラフである。FIG. 1 is a graph showing the relationship between temperature and specific resistance in Examples and Comparative Examples.
Claims (1)
−ＳｉＣ結晶粒を少なくとも１０％含有する炭化珪素質
焼結体からなることを特徴とする炭化珪素発熱体。1. An N-type semiconductor having a solid solution of nitrogen, wherein β
-A silicon carbide heating element comprising a silicon carbide-based sintered body containing at least 10% of SiC crystal grains.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5257760A JPH0789764A (en) | 1993-09-21 | 1993-09-21 | Silicon carbide heating element |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5257760A JPH0789764A (en) | 1993-09-21 | 1993-09-21 | Silicon carbide heating element |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0789764A true JPH0789764A (en) | 1995-04-04 |
Family
ID=17310721
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5257760A Pending JPH0789764A (en) | 1993-09-21 | 1993-09-21 | Silicon carbide heating element |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0789764A (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2000007959A1 (en) * | 1998-08-07 | 2000-02-17 | Bridgestone Corporation | Silicon carbide sinter and process for producing the same |
| US6090733A (en) * | 1997-08-27 | 2000-07-18 | Bridgestone Corporation | Sintered silicon carbide and method for producing the same |
| JP2005219937A (en) * | 2004-02-03 | 2005-08-18 | Bridgestone Corp | Silicon carbide sintered compact containing phosphorus, silicon carbide powder to be raw material of the same, and method of manufacturing these |
| WO2012043749A1 (en) | 2010-09-29 | 2012-04-05 | 日本碍子株式会社 | Silicon carbide ceramic and honeycomb structure |
| WO2012043752A1 (en) | 2010-09-29 | 2012-04-05 | 日本碍子株式会社 | Method for producing silicon carbide ceramic and method for producing honeycomb structure |
| JP2014187112A (en) * | 2013-03-22 | 2014-10-02 | Toshiba Corp | Semiconductor device and method for manufacturing the same |
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-
1993
- 1993-09-21 JP JP5257760A patent/JPH0789764A/en active Pending
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6090733A (en) * | 1997-08-27 | 2000-07-18 | Bridgestone Corporation | Sintered silicon carbide and method for producing the same |
| US6214755B1 (en) | 1997-08-27 | 2001-04-10 | Bridgestone Corporation | Method for producing sintered silicon carbide |
| WO2000007959A1 (en) * | 1998-08-07 | 2000-02-17 | Bridgestone Corporation | Silicon carbide sinter and process for producing the same |
| US6695984B1 (en) | 1998-08-07 | 2004-02-24 | Bridgestone Corporation | Silicon carbide sinter and process for producing the same |
| JP2005219937A (en) * | 2004-02-03 | 2005-08-18 | Bridgestone Corp | Silicon carbide sintered compact containing phosphorus, silicon carbide powder to be raw material of the same, and method of manufacturing these |
| WO2012043752A1 (en) | 2010-09-29 | 2012-04-05 | 日本碍子株式会社 | Method for producing silicon carbide ceramic and method for producing honeycomb structure |
| WO2012043749A1 (en) | 2010-09-29 | 2012-04-05 | 日本碍子株式会社 | Silicon carbide ceramic and honeycomb structure |
| US8859075B2 (en) | 2010-09-29 | 2014-10-14 | Ngk Insulators, Ltd. | Silicon carbide ceramic and honeycomb structure |
| US9120706B2 (en) | 2010-09-29 | 2015-09-01 | Ngk Insulators, Ltd. | Method for producing silicon carbide ceramic and method for producing honeycomb structure |
| JP2014187112A (en) * | 2013-03-22 | 2014-10-02 | Toshiba Corp | Semiconductor device and method for manufacturing the same |
| JP2016183081A (en) * | 2015-03-26 | 2016-10-20 | 東京窯業株式会社 | Manufacturing method of conductive silicon carbide sintered body and conductive silicon carbide sintered body |
| JP2019172495A (en) * | 2018-03-28 | 2019-10-10 | 東京窯業株式会社 | Manufacturing method of conductive carbonized silicon sintered body and conductive carbonized silicon sintered body |
| DE102021213628A1 (en) | 2021-03-03 | 2022-09-08 | Ngk Insulators, Ltd. | Honeycomb structure, electric heater and emission control device |
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