JPH05200271A - Method for growing iib type diamond single crystal - Google Patents
Method for growing iib type diamond single crystalInfo
- Publication number
- JPH05200271A JPH05200271A JP4011117A JP1111792A JPH05200271A JP H05200271 A JPH05200271 A JP H05200271A JP 4011117 A JP4011117 A JP 4011117A JP 1111792 A JP1111792 A JP 1111792A JP H05200271 A JPH05200271 A JP H05200271A
- Authority
- JP
- Japan
- Prior art keywords
- diamond
- crystal
- boron
- carbon source
- iib
- 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.)
- Pending
Links
Landscapes
- Crystals, And After-Treatments Of Crystals (AREA)
- Carbon And Carbon Compounds (AREA)
Abstract
Description
【0001】[0001]
【産業上の利用分野】本発明は、サーミスタやトランジ
スタなどに用いられる半導体特性を有する大型のIIb型
ダイヤモンド単結晶の育成方法に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for growing a large IIb type diamond single crystal having semiconductor characteristics used for thermistors and transistors.
【0002】[0002]
【従来の技術】ダイヤモンドは、SiやGaAsなどの
従来の半導体材料に比較してバンドギャップが大きく、
また熱伝導率が高いため、作動温度域が広く、かつ放熱
特性に優れた半導体デバイス、半導体基板が期待でき
る。ダイヤモンド合成時にホウ素(B)を添加すること
で、p型の半導体特性を示すIIb型と呼ばれる青色を呈
するダイヤモンド結晶が合成できることが知られてい
る。たとえば特公昭38−9552号公報には、高温高
圧下で、触媒を用いて非ダイヤモンド炭素質物質をダイ
ヤモンドに変換する際に、ホウ素もしくは炭化ホウ素、
酸化ホウ素、窒化ホウ素、ホウ化ニッケル、水素化ホウ
素リチウムなどを添加することにより、導電性に優れた
IIb型ダイヤモンドを製造することを開示している。さ
らに、The Journal of Physical Chemistry, Vol.75, N
o.12, (1971)1838には、温度差法により溶媒中に微量の
ホウ素を添加して育成された1カラット級のIIb型ダイ
ヤモンドが示されている。2. Description of the Related Art Diamond has a larger band gap than conventional semiconductor materials such as Si and GaAs.
Further, since the thermal conductivity is high, a semiconductor device and a semiconductor substrate having a wide operating temperature range and excellent heat dissipation characteristics can be expected. It is known that by adding boron (B) at the time of diamond synthesis, it is possible to synthesize a blue-colored diamond crystal called IIb type that exhibits p-type semiconductor characteristics. For example, Japanese Examined Patent Publication No. 38-9552 discloses that when a non-diamond carbonaceous material is converted to diamond by using a catalyst under high temperature and high pressure, boron or boron carbide,
Excellent conductivity by adding boron oxide, boron nitride, nickel boride, lithium borohydride, etc.
Disclosed is the manufacture of type IIb diamond. In addition, The Journal of Physical Chemistry, Vol.75, N
o.12, (1971) 1838 shows a 1-ct class IIb diamond grown by adding a trace amount of boron to a solvent by a temperature difference method.
【0003】[0003]
【発明が解決しようとする課題】しかし、従来の合成方
法で得られるIIb型ダイヤモンド結晶は、実際に半導体
材料として使用することは不可能であった。その最大の
理由は、結晶中のホウ素の分布がかなり不均一であり、
電気的特性が、結晶の場所や方向により大きく異なるた
めである。ホウ素の分布が不均一となる理由はよく解っ
ていないが、現象として、ダイヤモンド結晶成長中に、
結晶中に取り込まれるホウ素の量が成長面によって大き
く異なることが知られている。たとえば、ダイヤモンド
の(111)面にはホウ素が取り込まれ易く、(10
0)面や(110)面、(113)面などの成長面には
殆どホウ素は取り込まれない。また、合成条件によって
は同一成長面内でもホウ素の濃度分布にかなりの濃淡が
見られることもある。また、通常のダイヤモンド合成で
は、溶媒中の微量の窒素が、結晶成長中に置換型で取り
込まれ、Ib型と呼ばれる黄色味を帯びた結晶(この場
合の窒素のドナー準位は深く、半導体特性は示さない)
となるが、この窒素の分布も、結晶内でかなり不均一で
ある。このように窒素が結晶成長中に結晶内に取り込ま
れるような状態でホウ素を添加した場合は、結晶内のホ
ウ素の濃度分布はより不均一なものとなり、また、ホウ
素は窒素と共存することにより電気的に中和され、ダイ
ヤモンド結晶の半導体特性はさらに不安定で不均一なも
のになる。以上のようなホウ素の濃度分布の不均一性
は、結晶が大型になるにつれ顕著になり、また合成温度
条件の微妙な変化の影響を受け易くなる。本発明は上記
のような問題点を解決して、結晶内のホウ素の分布が均
一で半導体特性の優れたIIb型ダイヤモンド単結晶の育
成方法を課題とするものである。However, the IIb type diamond crystal obtained by the conventional synthesis method cannot be actually used as a semiconductor material. The main reason for this is that the distribution of boron in the crystal is quite uneven,
This is because the electrical characteristics greatly differ depending on the place and direction of the crystal. The reason why the distribution of boron is non-uniform is not well understood, but as a phenomenon, during diamond crystal growth,
It is known that the amount of boron taken into the crystal varies greatly depending on the growth surface. For example, boron is easily incorporated into the (111) plane of diamond,
Boron is hardly incorporated into the growth planes such as the (0) plane, the (110) plane, and the (113) plane. Further, depending on the synthesis conditions, there may be a case where a considerable concentration is observed in the boron concentration distribution within the same growth plane. Further, in normal diamond synthesis, a trace amount of nitrogen in a solvent is taken in by substitution during crystal growth, and a yellowish crystal called Ib type (in this case, the nitrogen donor level is deep, Is not shown)
However, the distribution of nitrogen is also quite uneven within the crystal. When boron is added in such a state that nitrogen is taken into the crystal during crystal growth, the concentration distribution of boron in the crystal becomes more non-uniform, and boron coexists with nitrogen. Being electrically neutralized, the semiconductor properties of diamond crystals become more unstable and non-uniform. The non-uniformity of the boron concentration distribution as described above becomes more remarkable as the size of the crystal becomes larger, and is more susceptible to the subtle changes in the synthesis temperature conditions. An object of the present invention is to solve the above problems and to provide a method for growing a IIb type diamond single crystal having a uniform distribution of boron in the crystal and excellent semiconductor characteristics.
【0004】[0004]
【課題を解決するための手段】本発明は、高温部に炭素
源、低温部にダイヤモンドの種結晶を配し、該炭素源と
該種結晶の間に溶媒を配して、該溶媒が溶解する温度以
上、ダイヤモンドか熱的に安定となる圧力以上の条件で
保持し、該種結晶上に新たなダイヤモンド結晶を育成す
る方法において、該炭素源としてホウ素を孤立置換型不
純物として結晶内に含むIIb型ダイヤモンドを用いて、
該種結晶上に、少なくとも該炭素源に用いたIIb型ダイ
ヤモンドより大きく結晶内部のホウ素濃度分布が均一で
あるIIb型ダイヤモンド結晶を育成することを特徴とす
る。また、前記ダイヤモンド育成条件下でダイヤモンド
が種結晶上に育成される際に、窒素および該炭素源のII
b型ダイヤモンド中のホウ素以外のホウ素が結晶内に取
り込まれない状態で育成することが特に好ましい。図1
は本発明の試料室構成の一例を示す概略説明図であり、
1は炭素源であって孤立置換型不純物としてホウ素を含
有するIIb型ダイヤモンドであり、2は溶媒、3はダイ
ヤモンド種結晶、4は絶縁体、5は黒鉛ヒーター、6は
圧力媒体を示す。According to the present invention, a carbon source is placed in a high temperature portion and a diamond seed crystal is placed in a low temperature portion, and a solvent is placed between the carbon source and the seed crystal, and the solvent is dissolved. In the method of growing a new diamond crystal on the seed crystal by holding the diamond at a temperature equal to or higher than the temperature at which the diamond is thermally stable or at a pressure equal to or higher than the pressure, boron is contained in the crystal as an isolated substitution impurity as the carbon source With IIb type diamond,
On the seed crystal, a IIb type diamond crystal is grown, which is larger than the IIb type diamond used as the carbon source and has a uniform boron concentration distribution inside the crystal. In addition, when diamond is grown on the seed crystal under the above-mentioned diamond growing conditions, the amount of nitrogen and the carbon source II
It is particularly preferable to grow the b-type diamond in a state where boron other than boron in the crystal is not taken into the crystal. Figure 1
Is a schematic explanatory view showing an example of a sample chamber configuration of the present invention,
1 is a IIb type diamond containing a carbon source and containing boron as an isolated substitution type impurity, 2 is a solvent, 3 is a diamond seed crystal, 4 is an insulator, 5 is a graphite heater, and 6 is a pressure medium.
【0005】[0005]
【作用】本発明者等は、窒素が結晶中に少しでも残留す
るとホウ素の分布や電気的特性にムラが生じることか
ら、窒素を完全に除去した状態でホウ素を添加すること
を試み、さらにホウ素の添加方法を種々検討して、ホウ
素を結晶中に均一に添加するのに有効な方法を探索し
た。その結果、温度差法によるダイヤモンド育成におい
て、炭素源にホウ素を孤立置換型不純物として含むIIb
型ダイヤモンドを用いて、このダイヤモンド中のホウ素
のみをドーパントとして育成結晶中に添加する方法をと
ると、ホウ素が均一に分布した大型のIIb型ダイヤモン
ド単結晶が安定して得られることを見い出した。孤立置
換型でホウ素を結晶格子内に含むダイヤモンドを炭素源
とすると、これが溶媒中に溶解しても、ホウ素元素はダ
イヤモンド結晶中で隣接している炭素元素とは完全に分
離せずに、クラスター状態(注:溶媒中に溶け込んで液
体となっても各炭素元素,ホウ素元素が微視的に原料の
ダイヤモンドの構造を保っている状態)で炭素元素とと
もに、溶媒中を拡散し、成長するダイヤモンド結晶上に
組み込まれていくものと考えられ、そのため、ホウ素が
凝集したり、成長面によってムラが生じたりせず、均一
に育成結晶中に取り込まれていくものと考えられる。こ
うして育成されたIIb型ダイヤモンド結晶は1カラット
級の大型結晶でも成長面や成長温度条件の違いによるホ
ウ素の濃度の差がほとんどなく、従来のものに比べ、か
なり安定した半導体特性を有することを確認し、本発明
を完成した。The inventors of the present invention tried to add boron in a state where nitrogen was completely removed, because the distribution and electrical characteristics of boron become uneven if nitrogen remains in the crystal even a little. The various addition methods were investigated to find an effective method for uniformly adding boron into the crystal. As a result, in the diamond growth by the temperature difference method, IIb containing boron as an isolated substitution impurity as a carbon source.
It has been found that a large IIb type diamond single crystal in which boron is uniformly distributed can be stably obtained by adopting a method in which only boron in the diamond is added as a dopant to the grown crystal using a type diamond. When diamond, which is an isolated substitution type and has boron in the crystal lattice, is used as the carbon source, the boron element does not completely separate from the adjacent carbon element in the diamond crystal even if it dissolves in the solvent, Diamond that diffuses in the solvent together with the carbon element in the state (Note: each carbon element and boron element microscopically retains the structure of the starting diamond even if it dissolves in the solvent to become a liquid) It is considered that they are incorporated into the crystal, and therefore, it is considered that the boron is uniformly incorporated into the grown crystal without aggregating or causing unevenness on the growth surface. It has been confirmed that the IIb type diamond crystal thus grown has a substantially stable semiconductor characteristic compared to the conventional one, with almost no difference in the boron concentration due to the difference in the growth surface or the growth temperature condition even with a 1-carat large crystal. Then, the present invention has been completed.
【0006】本発明において炭素源に用いるホウ素含有
のIIb型ダイヤモンドとしては、通常の高圧高温合成法
においては炭素源もしくは触媒(溶媒)中にホウ素を添
加することにより、あるいはCVDなどの気相合成法に
おいてはホウ素を含むガスを原料として用いることによ
り、ホウ素を所定量結晶中にドープして得られたIIb型
ダイヤモンドの粉末や粒状体あるいは多結晶体を所定の
形状に成形、加工したもの、もしくは粒状や多結晶体状
のIIb型ダイヤモンドを粉砕した粉末を型押し成形ある
いは高温高圧下で焼成した焼結体など、いずれの形態の
ものも使用することができる。但し、ホウ素はすべて孤
立置換型不純物としてダイヤモンド結晶中に含まれてい
る必要があり、それ以外の形態のホウ素不純物を含むも
のは好ましくない。本発明において炭素源として用いる
ダイヤモンド中のホウ素の含有量は1ppm以上である
ことが好ましい。1ppmより少ないと目的とする半導
体特性を有するダイヤモンドを得ることが困難となる。
また結晶中で凝集しないかぎりホウ素含有量に上限値は
ない。一般的にはホウ素含有量が1000ppmを越え
るダイヤモンドでは、部分的にホウ素が凝集し易くなる
ため好ましくない。また、炭素源ダイヤモンド中の孤立
置換型以外のホウ素不純物の含有量は具体的には1pp
m以下であることが好ましい。As the boron-containing IIb type diamond used as a carbon source in the present invention, boron is added to a carbon source or a catalyst (solvent) in a usual high-pressure high-temperature synthesis method, or vapor phase synthesis such as CVD. In the method, by using a gas containing boron as a raw material, IIb type diamond powder or granules or polycrystals obtained by doping a predetermined amount of boron into a crystal are molded and processed into a predetermined shape, Alternatively, any form such as a powder obtained by crushing granular or polycrystalline IIb type diamond powder by embossing or sintered at high temperature and high pressure can be used. However, it is necessary that all the boron is contained in the diamond crystal as an isolated substitution type impurity, and it is not preferable to contain boron impurities in other forms. The content of boron in diamond used as a carbon source in the present invention is preferably 1 ppm or more. If it is less than 1 ppm, it will be difficult to obtain a diamond having desired semiconductor characteristics.
There is no upper limit to the boron content as long as it does not aggregate in the crystal. In general, diamond having a boron content of more than 1000 ppm is not preferable because boron is likely to partially aggregate. Further, the content of boron impurities other than the isolated substitution type carbon source diamond is specifically 1 pp.
It is preferably m or less.
【0007】本発明においては、ダイヤモンド育成条件
下でダイヤモンドが種結晶上に育成される際に、炭素源
のIIb型ダイヤモンド中のホウ素以外のホウ素が結晶内
に取り込まれない状態を実現するためには、前記のよう
に炭素源としてのIIb型ダイヤモンド中の孤立置換型不
純物としてのホウ素以外のホウ素不純物が実質的にない
状態にすることに加え、溶媒の中に不純物としてホウ素
を殆ど含まないことが必要であり、溶媒中の不純物ホウ
素の含有量が1ppm以下であることが好ましい。溶媒
中に1ppmをこえるホウ素が含まれていると、そのホ
ウ素が育成中のダイヤモンド結晶中に取り込まれるよう
になり、育成したダイヤモンド結晶中のホウ素の分布の
不均一性が目立ち、電気的特性が結晶の場合や方向によ
り違ったものとなり、半導体材料としては使用できなく
なる。本発明の溶媒としては通常のダイヤモンド合成の
触媒もしくは溶媒としてよく用いられる金属、たとえば
Fe,Co,Ni,Mn,Crなど、もしくはこれら金
属からなる合金、のいずれをも用いることができる。In the present invention, in order to realize a state where boron other than boron in the carbon source IIb type diamond is not taken into the crystal when the diamond is grown on the seed crystal under the diamond growing condition. As described above, in addition to the condition that there is substantially no boron impurity other than boron as an isolated substitutional impurity in type IIb diamond as a carbon source, the solvent contains almost no boron as an impurity. Is necessary, and the content of the impurity boron in the solvent is preferably 1 ppm or less. When the solvent contains more than 1 ppm of boron, the boron is taken into the growing diamond crystal, and the unevenness of the boron distribution in the grown diamond crystal is noticeable, and the electrical characteristics are improved. It becomes different depending on the case and direction of crystals, and cannot be used as a semiconductor material. As the solvent of the present invention, any of the metals that are often used as a catalyst or solvent for ordinary diamond synthesis, such as Fe, Co, Ni, Mn, Cr, etc., or alloys of these metals can be used.
【0008】また、ダイヤモンド育成条件下でダイヤモ
ンドが種結晶上に育成される際に、窒素が成長結晶内に
取り込まれない状態を実現するためには、溶媒および炭
素源に窒素不純物を含まないものを用いて、試料室全体
を真空脱気して試料室内の窒素ガスを十分除去した状態
でダイヤモンドを育成するか、あるいは溶媒中に窒素ゲ
ッターを必要量添加しておく。窒素ゲッターとしては、
たとえばAl,Ti,Zr,Hr,V,Nb,Taなど
の金属、もしくはこれらの元素の2種以上からなる合金
など、窒素との反応性の高い物質でダイヤモンドの結晶
成長を阻害しないものはすべて用いることができる。こ
れら窒素ゲッターを用いる場合は育成ダイヤモンド結晶
中に窒素が殆ど残留しない程度の十分な量を添加する必
要がある。本発明者らの実験によれば、窒素ゲッターの
添加量は溶媒に対し、1〜5重量%が一般的であった。
以上のような構成で、図1において炭素源(1)部と種
結晶(3)部の間に、炭素源側が高温となるように適当
な温度勾配をつけ、溶媒の融点以上の温度で、ダイヤモ
ンドが熱的に安定な領域となるような高圧高温条件で、
長時間保持することにより、1カラット級もしくはそれ
以上の大型でなおかつホウ素が均一に分布したIIb型ダ
イヤモンド単結晶を育成することができる。Further, in order to realize a state in which nitrogen is not taken into the grown crystal when diamond is grown on the seed crystal under the diamond growing condition, the solvent and the carbon source do not contain nitrogen impurities. Using, the diamond sample is grown in a state where the entire sample chamber is vacuum degassed and nitrogen gas in the sample chamber is sufficiently removed, or a necessary amount of nitrogen getter is added to the solvent. As a nitrogen getter,
For example, all metals that have high reactivity with nitrogen, such as Al, Ti, Zr, Hr, V, Nb and Ta, or alloys consisting of two or more of these elements, that do not inhibit diamond crystal growth Can be used. When these nitrogen getters are used, it is necessary to add a sufficient amount such that nitrogen hardly remains in the grown diamond crystal. According to the experiments conducted by the present inventors, the amount of the nitrogen getter added is generally 1 to 5% by weight based on the solvent.
With the above-described structure, an appropriate temperature gradient is provided between the carbon source (1) portion and the seed crystal (3) portion in FIG. 1 so that the carbon source side has a high temperature, and at a temperature equal to or higher than the melting point of the solvent, Under high pressure and high temperature conditions where diamond is in a thermally stable region,
By holding for a long time, it is possible to grow a IIb type diamond single crystal having a large size of 1 carat or more and having a uniform distribution of boron.
【0009】[0009]
実施例1 炭素源として、孤立置換型不純物としてホウ素(B)を
約5ppm含む粒径約20μmのIIb型ダイヤモンド粉
末を、直径20mm、厚み5mmに型押し成形したもの
を用いた。溶媒金属として高純度のFe−40Co合金
(重量比でFe:Co=60:40、直径20mm、厚
み10mm)を用い、これに窒素ゲッターとしてAlお
よびTiをそれぞれ1.0重量%添加した。溶媒金属中
のB含有量は化学分析(ICP発光分光分析)の結果
0.1ppm以下(検出限界)でほとんど含まれていな
かった。種結晶には直径約500μmのダイヤモンド結
晶3個を用いた。そして、図1に示す試料室構成で、炭
素源と種結晶部に約30℃の温度差がつくように加熱ヒ
ーター内にセットし、超高圧発生装置を用いて、圧力
5.5Pa、温度1300℃で70時間保持し、ダイヤ
モンドの育成を行った。その結果、0.7〜0.9カラ
ットの薄く青色がかった良質なIIb型ダイヤモンド単結
晶が得られた。これらの結晶を中央部でレーザーでスラ
イスカットしたのち研磨し、結晶断面を観察すると、青
色の濃淡は殆ど見られなかった。また結晶内各所でのB
含有量をSIMS(二次イオン質量分析)により分析し
た結果、B含有量の場所による違いは殆ど観察されず、
いずれの場所でもB含有量は1.3ppmを示した。四
探針法により測定した抵抗率は220Ω・cmで、場所
および方向による違いは殆ど認められなかった。Example 1 As a carbon source, IIb type diamond powder having a particle size of about 20 μm and containing about 5 ppm of boron (B) as an isolated substitution type impurity was pressed and shaped into a diameter of 20 mm and a thickness of 5 mm. A high-purity Fe-40Co alloy (weight ratio of Fe: Co = 60: 40, diameter: 20 mm, thickness: 10 mm) was used as a solvent metal, and 1.0% by weight of Al and Ti were added thereto as a nitrogen getter. The content of B in the solvent metal was 0.1 ppm or less (detection limit) as a result of chemical analysis (ICP emission spectroscopic analysis) and was hardly contained. Three diamond crystals with a diameter of about 500 μm were used as seed crystals. Then, in the sample chamber configuration shown in FIG. 1, the carbon source and the seed crystal part were set in a heater so that there was a temperature difference of about 30 ° C., and a pressure of 5.5 Pa and a temperature of 1300 were used by using an ultrahigh pressure generator. The diamond was grown by holding at 70 ° C. for 70 hours. As a result, a good blue-tinted IIb type diamond single crystal of 0.7 to 0.9 carat was obtained. When these crystals were slice-cut at the center with a laser and then polished, and the crystal cross section was observed, almost no shade of blue was observed. In addition, B in various places in the crystal
As a result of analyzing the content by SIMS (secondary ion mass spectrometry), almost no difference in B content depending on the location was observed,
The B content was 1.3 ppm at any of the locations. The resistivity measured by the four-point probe method was 220 Ω · cm, and almost no difference due to location or direction was observed.
【0010】実施例2 炭素源として、孤立置換型不純物としてBを約25pp
m含むIIb型ダイヤモンド粉末を用いた以外は、実施例
1と同様にして、ダイヤモンドの育成を行った。その結
果、0.7〜0.9カラットの青色の良質なIIb型のダ
イヤモンド単結晶が得られた。結晶断面の観察では、青
色の濃淡は殆ど見られなかった。また結晶内各所でのB
含有量をSIMSにより分析した結果、B含有量の場所
による違いはほとんど観察されず、いずれの場所でもB
含有量は7ppmを示した。四探針法により測定した抵
抗率は80Ω・cmで、場所および方向による違いは殆
ど認められなかった。Example 2 About 25 pp of B as an isolated substitution type impurity as a carbon source
Diamond was grown in the same manner as in Example 1 except that IIb type diamond powder containing m was used. As a result, a good blue IIb type diamond single crystal of 0.7 to 0.9 carat was obtained. In the observation of the crystal cross section, almost no shade of blue was seen. In addition, B in various places in the crystal
As a result of analyzing the content by SIMS, almost no difference in B content depending on the location was observed, and B content was B at any location.
The content was 7 ppm. The resistivity measured by the four-point probe method was 80 Ω · cm, and almost no difference due to location or direction was recognized.
【0011】実施例3 炭素源として、孤立置換型不純物としてBを約200p
pm含むIIb型ダイヤモンド粉末を用いた以外は、実施
例1と同様にして、ダイヤモンドの育成を行った。その
結果、0.7〜0.9カラットの深青色の良質なIIb型
のダイヤモンド単結晶が得られた。結晶断面の観察で
は、青色の濃淡は殆ど見られなかった。また結晶内各所
でのB含有量をSIMSにより分析した結果、B含有量
の場所による違いはほとんど観察されず、いずれの場所
でもB含有量は48ppmを示した。四探針法により測
定した抵抗率は20Ω・cmで、場所および方向による
違いは殆ど認められなかった。Example 3 As a carbon source, B as an isolated substitution type impurity of about 200 p
Diamond was grown in the same manner as in Example 1 except that IIb type diamond powder containing pm was used. As a result, a 0.7 to 0.9 carat deep blue good quality IIb type diamond single crystal was obtained. In the observation of the crystal cross section, almost no shade of blue was seen. Moreover, as a result of analyzing the B content at various points in the crystal by SIMS, almost no difference in the B content depending on the location was observed, and the B content was 48 ppm at any location. The resistivity measured by the four-point probe method was 20 Ω · cm, and almost no difference due to location or direction was observed.
【0012】比較例1 炭素源としてBを殆ど含まない(含有量0.1ppm以
下〔検出限界以下〕)ダイヤモンド粉末を用いた以外は
実施例1と同様にしてダイヤモンドの育成を行った。そ
の結果、約0.8カラットの無色透明なダイヤモンド結
晶(IIa型)が得られた。ESRにより、得られたダイ
ヤモンド結晶の窒素濃度を測定するといずれも0.1p
pm以下であった。SIMSによる分析では、Bは殆ど
検出されなかった。電気伝導性はほとんどなく、絶縁体
であった。Comparative Example 1 Diamond was grown in the same manner as in Example 1 except that diamond powder containing almost no B (content less than 0.1 ppm [below detection limit]) was used as a carbon source. As a result, colorless and transparent diamond crystals (type IIa) of about 0.8 carat were obtained. The nitrogen concentration of the obtained diamond crystal was measured by ESR and found to be 0.1 p
It was pm or less. Almost no B was detected by SIMS analysis. It had little electrical conductivity and was an insulator.
【0013】比較例2 炭素源としてBを殆ど含まない(含有量0.1ppm以
下〔検出限界以下〕)ダイヤモンド粉末に0.1重量%
のホウ素粉末を添加したものをを用いた以外は実施例1
と同様にしてダイヤモンドの育成を行った。 その結
果、約0.7〜0.9カラットの青色のIIb型ダイヤモ
ンド単結晶が得られたが、結晶の断面を観察すると、成
長面によって、青色の濃度の違いが見られた。すなわ
ち、(111)成長面はや濃淡はあるものの一面青色を
呈してしたのに対し、(100)成長面は無色に近かっ
た。各所でのB含有量をSIMSにより分析した結果、
(111)成長面では0.9〜1.5ppm、(10
0)成長面では約0.1ppmと成長面により大きく異
なり、また同一成長面内でもバラツキが大きかった。四
探針法により測定した抵抗率も200〜10000Ω・
cmと、結晶の場所によって大きく異なっていた。Comparative Example 2 0.1% by weight of diamond powder containing almost no B as a carbon source (content 0.1 ppm or less [below detection limit])
Example 1 except that the boron powder of Example 1 was used.
Diamonds were grown in the same manner as in. As a result, a blue IIb type diamond single crystal of about 0.7 to 0.9 carat was obtained, but when the cross section of the crystal was observed, a difference in blue concentration was observed depending on the growth surface. That is, although the (111) growth surface was slightly shaded, one surface was blue, while the (100) growth surface was nearly colorless. As a result of analyzing the B content in each place by SIMS,
In the (111) growth plane, 0.9-1.5 ppm, (10
0) The growth surface was about 0.1 ppm, which was greatly different depending on the growth surface, and the variation was large even within the same growth surface. The resistivity measured by the four-point probe method is also 200 to 10,000 Ω.
cm and the location of the crystal greatly differed.
【0014】比較例3 溶媒金属として、Bを5ppm含むものを用いたこと以
外は実施例1と同様にしてダイヤモンドの育成をおこな
った。その結果、約0.7〜0.9カラットの薄く青色
がかったIIb型ダイヤモンド単結晶が得られた。結晶の
断面を観察すると、成長面によって、青色の濃度の違い
が見られた。すなわち、(111)成長面はやや濃淡は
あるものの一面薄く青色を呈していたのに対し、(10
0)成長面とほとんど無色であった。各所でのB含有量
をSIMSにより分析した結果、(111)成長面では
0.2〜0.3ppm、(100)成長面ではBは検出
されなかった。また(111)成長面内でもB濃度のバ
ラツキがと大きかった。四探針法により抵抗率の測定を
試みたが、結晶の場所による違いが大きく、場合によっ
ては電気伝導性が見られなかった。Comparative Example 3 Diamond was grown in the same manner as in Example 1 except that a solvent metal containing B of 5 ppm was used. As a result, a thin bluish IIb type diamond single crystal of about 0.7 to 0.9 carat was obtained. When the cross section of the crystal was observed, a difference in blue concentration was observed depending on the growth surface. That is, although the (111) growth surface was slightly shaded, it was pale blue on one side,
0) It was almost colorless with the growth surface. As a result of analyzing the B content in each place by SIMS, 0.2 to 0.3 ppm was detected on the (111) growth surface, and B was not detected on the (100) growth surface. In addition, the variation in B concentration was large even in the (111) growth plane. An attempt was made to measure the resistivity by the four-point probe method, but there was a large difference depending on the location of the crystal, and in some cases no electrical conductivity was observed.
【0015】[0015]
【発明の効果】以上説明したように、本発明によれば、
ホウ素が均一に分散した大型のIIb型ダイヤモンド結晶
が得られる。本発明による合成ダイヤモンドは、サーミ
スタやトランジスタなどの半導体材料として利用するこ
とができる。As described above, according to the present invention,
A large IIb type diamond crystal in which boron is uniformly dispersed can be obtained. The synthetic diamond according to the present invention can be used as a semiconductor material such as a thermistor or a transistor.
【図1】 本発明の一具体例であって、ダイヤモンド単
結晶育成用の試料室構成の概略説明図である。FIG. 1 is a schematic explanatory diagram of a sample chamber configuration for growing a diamond single crystal, which is one specific example of the present invention.
1 炭素源 2 溶媒金属 3 種結晶 4 絶縁体 5 黒鉛ヒーター 6 圧力媒体 1 carbon source 2 solvent metal 3 seed crystal 4 insulator 5 graphite heater 6 pressure medium
Claims (2)
の種結晶を配し、該炭素源と該種結晶の間に溶媒を配し
て、該溶媒が溶解する温度以上、ダイヤモンドか熱的に
安定となる圧力以上の条件で保持し、該種結晶上に新た
なダイヤモンド結晶を育成する方法において、該炭素源
としてホウ素を孤立置換型不純物として結晶内に含むII
b型ダイヤモンドを用いて、該種結晶上に、少なくとも
該炭素源に用いたIIb型ダイヤモンドより大きく結晶内
部のホウ素濃度分布が均一であるIIb型ダイヤモンド結
晶を育成することを特徴とする上記方法。1. A carbon source is placed in a high temperature part and a seed crystal of diamond is placed in a low temperature part, and a solvent is placed between the carbon source and the seed crystal, and the temperature is higher than the temperature at which the solvent is dissolved, and the diamond or the thermal In a method of maintaining a pressure equal to or higher than a stable pressure to grow a new diamond crystal on the seed crystal, boron is contained as an isolated substitution type impurity in the crystal in the crystal II
The method as described above, wherein b-type diamond is used to grow, on said seed crystal, a IIb-type diamond crystal having at least a larger concentration distribution of boron inside the crystal than the IIb-type diamond used as the carbon source.
ンドが種結晶上に育成される際に、窒素および該炭素源
のIIb型ダイヤモンド中のホウ素以外のホウ素が結晶内
に取り込まれない状態で育成することを特徴とする請求
項1記載の上記方法。2. When the diamond is grown on the seed crystal under the diamond growing conditions, it is grown in a state in which nitrogen and boron other than boron in the carbon source IIb type diamond are not taken into the crystal. The method according to claim 1, characterized in that
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP4011117A JPH05200271A (en) | 1992-01-24 | 1992-01-24 | Method for growing iib type diamond single crystal |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP4011117A JPH05200271A (en) | 1992-01-24 | 1992-01-24 | Method for growing iib type diamond single crystal |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH05200271A true JPH05200271A (en) | 1993-08-10 |
Family
ID=11769070
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP4011117A Pending JPH05200271A (en) | 1992-01-24 | 1992-01-24 | Method for growing iib type diamond single crystal |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH05200271A (en) |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0894766A1 (en) * | 1997-08-01 | 1999-02-03 | Tokyo Gas Co., Ltd. | Boron-doped isotopic diamond and process for producing the same |
US6433474B1 (en) | 1997-12-29 | 2002-08-13 | Tokyo Gas Co., Ltd. | Current injection-type diamond ultraviolet light-emitting device |
JP2008522807A (en) * | 2004-12-09 | 2008-07-03 | エレメント シックス (プロダクション)(プロプライエタリィ) リミテッド | Diamond synthesis |
US7404399B2 (en) | 2003-10-10 | 2008-07-29 | Sumitomo Electric Industries, Ltd. | Diamond tool, synthetic single crystal diamond and method of synthesizing single crystal diamond, and diamond jewelry |
JP2017160089A (en) * | 2016-03-10 | 2017-09-14 | 並木精密宝石株式会社 | Diamond substrate and method for manufacturing the same |
CN107824128A (en) * | 2017-10-31 | 2018-03-23 | 江苏西玉钻石科技有限公司 | A kind of double carbon source synthesis of artificial diamond preparation facilities and preparation method |
-
1992
- 1992-01-24 JP JP4011117A patent/JPH05200271A/en active Pending
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0894766A1 (en) * | 1997-08-01 | 1999-02-03 | Tokyo Gas Co., Ltd. | Boron-doped isotopic diamond and process for producing the same |
US6433474B1 (en) | 1997-12-29 | 2002-08-13 | Tokyo Gas Co., Ltd. | Current injection-type diamond ultraviolet light-emitting device |
US7404399B2 (en) | 2003-10-10 | 2008-07-29 | Sumitomo Electric Industries, Ltd. | Diamond tool, synthetic single crystal diamond and method of synthesizing single crystal diamond, and diamond jewelry |
EP2468392A2 (en) | 2003-10-10 | 2012-06-27 | Sumitomo Electric Industries, Ltd. | Diamond tool, synthetic single crystal diamond and method for synthesizing single crystal diamond, and diamond jewelry |
JP2008522807A (en) * | 2004-12-09 | 2008-07-03 | エレメント シックス (プロダクション)(プロプライエタリィ) リミテッド | Diamond synthesis |
JP2017160089A (en) * | 2016-03-10 | 2017-09-14 | 並木精密宝石株式会社 | Diamond substrate and method for manufacturing the same |
CN107824128A (en) * | 2017-10-31 | 2018-03-23 | 江苏西玉钻石科技有限公司 | A kind of double carbon source synthesis of artificial diamond preparation facilities and preparation method |
CN107824128B (en) * | 2017-10-31 | 2024-04-16 | 王国伟 | Preparation device and preparation method for double-carbon-source synthetic artificial diamond |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP5068423B2 (en) | Silicon carbide single crystal ingot, silicon carbide single crystal wafer, and manufacturing method thereof | |
Werner et al. | Growth and application of undoped and doped diamond films | |
US8216369B2 (en) | System for forming SiC crystals having spatially uniform doping impurities | |
EP2330236B1 (en) | METHOD AND APPARATUS FOR MANUFACTURING SiC SINGLE CRYSTAL FILM | |
US4152182A (en) | Process for producing electronic grade aluminum nitride films utilizing the reduction of aluminum oxide | |
CN101965419B (en) | Method for growing silicon carbide single crystal | |
JP5293732B2 (en) | Method for producing silicon carbide single crystal | |
JPH05200271A (en) | Method for growing iib type diamond single crystal | |
CN110284195A (en) | Boron phosphide single crystal and preparation method and application thereof | |
TWI785467B (en) | Semi-insulating single crystal silicon carbide wafer with high purity and silicon carbide crystal | |
JP5761264B2 (en) | Method for manufacturing SiC substrate | |
Ohtani et al. | Impurity incorporation kinetics during modified-Lely growth of SiC | |
JP3128179B2 (en) | Method for producing n-type silicon carbide single crystal | |
EP0894766B1 (en) | Boron-doped isotopic diamond and process for producing the same | |
US20010001385A1 (en) | Boron-doped isotopic diamond and process for producing the same | |
JP5487888B2 (en) | Method for producing n-type SiC single crystal | |
EP3072995A1 (en) | Method for producing silicon carbide crystals from vapour phase | |
JP2662608B2 (en) | Synthesis method of diamond single crystal film | |
JP3590464B2 (en) | Method for producing 4H type single crystal silicon carbide | |
JP3848446B2 (en) | Method for growing low resistance SiC single crystal | |
Semmelroth et al. | Growth of cubic SiC single crystals by the physical vapor transport technique | |
JP5794276B2 (en) | N-type SiC single crystal and use thereof | |
JP2003137694A (en) | Seed crystal for growing silicon carbide single crystal, silicon carbide single crystal ingot and method of producing the same | |
JP2002293694A (en) | Silicon carbide single crystal ingot and method of manufacturing for the same | |
JP5880200B2 (en) | Single crystal diamond and method for producing the same |