JPH08213326A - Manufacture of iii-v compound semiconductor crystal - Google Patents
Manufacture of iii-v compound semiconductor crystalInfo
- Publication number
- JPH08213326A JPH08213326A JP31967294A JP31967294A JPH08213326A JP H08213326 A JPH08213326 A JP H08213326A JP 31967294 A JP31967294 A JP 31967294A JP 31967294 A JP31967294 A JP 31967294A JP H08213326 A JPH08213326 A JP H08213326A
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- Japan
- Prior art keywords
- group
- compound semiconductor
- crystal
- substrate
- gas
- Prior art date
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- Physical Deposition Of Substances That Are Components Of Semiconductor Devices (AREA)
- Led Devices (AREA)
- Drying Of Semiconductors (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は３族元素として少なくと
もＧａ、５族元素として少なくともＮを含有する３−５
族化合物半導体を製造するに際して、目的の結晶とは異
なる材料の基板上にエピタキシャル結晶成長させて３−
５族化合物半導体を製造する方法に関する。The present invention relates to 3-5 containing at least Ga as a Group 3 element and at least N as a Group 5 element.
When a Group III compound semiconductor is manufactured, epitaxial crystal growth is performed on a substrate made of a material different from that of the target crystal.
The present invention relates to a method for manufacturing a Group 5 compound semiconductor.
【０００２】[0002]
【従来の技術】近年、紫外から可視までの発光領域をも
つ発光デバイス用素材としてＧａＮ、ＡｌＮ、ＩｎＮ又
はこれらの混晶である窒化ガリウム系化合物半導体が注
目されている。この窒化ガリウム系化合物半導体の結晶
成長方法としてはハイドライド気相成長（ＨＶＰＥ）
法、分子線エピタキシー（ＭＢＥ）法、そして有機金属
気相成長法（ＭＯＣＶＤ）法が知られている。2. Description of the Related Art In recent years, gallium nitride compound semiconductors, which are GaN, AlN, InN or a mixed crystal thereof, have been receiving attention as materials for light emitting devices having a light emitting region from ultraviolet to visible. As a crystal growth method for this gallium nitride-based compound semiconductor, hydride vapor phase epitaxy (HVPE) is used.
Methods, molecular beam epitaxy (MBE) method, and metal organic chemical vapor deposition (MOCVD) method are known.
【０００３】一方、窒化ガリウム系化合物半導体はバル
ク成長では良好な結晶が得られないため、そのものを基
板材料として用いるホモエピタキシャル成長は困難であ
る。従って成長させる膜とは異なる基板上に結晶成長を
行うヘテロエピタキシャル成長が好ましい。しかし、格
子整合する基板も少ないため一般的には大きな格子不整
合を持つα−アルミナ（１３．８％の格子不整合）、炭
化珪素（３．４％の格子不整合）、ＺｎＯ（２．０％の
格子不整合）、シリコン（２０．４％の格子不整合）等
の基板が用いられているのが実情である。On the other hand, a gallium nitride-based compound semiconductor cannot obtain a good crystal by bulk growth, so that it is difficult to perform homoepitaxial growth using itself as a substrate material. Therefore, heteroepitaxial growth in which crystal growth is performed on a substrate different from the film to be grown is preferable. However, since few substrates are lattice-matched, generally α-alumina (13.8% lattice mismatch), silicon carbide (3.4% lattice mismatch), ZnO (2. In reality, substrates such as 0% lattice mismatch) and silicon (20.4% lattice mismatch) are used.
【０００４】成長した結晶はヘテロエピタキシャル成長
であるため大面積の単結晶成長が非常に難しく、また多
くの欠陥を含んでいることが知られていた。一般に半導
体材料を発光デバイスとして用いる場合、結晶欠陥や不
純物は非発光中心となり発光効率等の特性に悪影響を及
ぼすこととなる。従って、結晶欠陥や不純物を極力低減
し、結晶性を向上させることが発光デバイスとして用い
る上で不可欠である。ところで先に述べた結晶成長方法
の中でＭＯＣＶＤ法では低温成長によるごく薄いＡｌＮ
又はＧａＮバッファ層を成長した上に、高温で本成長を
行う２段階成長が結晶性の改善に大きな影響を持つこと
が報告されている（特開平２−２２９４７６号、特公平
４−１５２００号、特開平４−２９７０２３号）。Since the grown crystal is heteroepitaxial, it has been known that it is very difficult to grow a large area single crystal and it contains many defects. In general, when a semiconductor material is used as a light emitting device, crystal defects and impurities become non-emissive centers and adversely affect characteristics such as light emission efficiency. Therefore, it is indispensable to reduce crystal defects and impurities as much as possible and improve the crystallinity for use as a light emitting device. By the way, among the crystal growth methods described above, in the MOCVD method, very thin AlN formed by low temperature growth is used.
Alternatively, it is reported that the two-step growth in which the GaN buffer layer is grown and then the main growth is carried out at a high temperature has a great influence on the improvement of crystallinity (Japanese Patent Laid-Open No. 2-229476, Japanese Patent Publication No. 4-15200). JP-A-4-297023).
【０００５】また、α−アルミナ基板の前処理法として
は成長開始前に水素雰囲気中で基板を１０００〜１２０
０℃の高温で処理することにより表面欠陥を無くす水素
クリーニング法が一般に用いられている。As a pretreatment method for the α-alumina substrate, the substrate is 1000 to 120 in a hydrogen atmosphere before the growth is started.
A hydrogen cleaning method, which eliminates surface defects by treating at a high temperature of 0 ° C., is generally used.
【０００６】[0006]
【発明が解決しようとする課題】一般にＨＶＰＥ法やＭ
ＯＣＶＤ法等の気相成長法では、結晶成長時に反応管壁
サセプタ表面等にも堆積物が生じる。この堆積物は、次
の結晶成長時に異物として悪影響を及ぼす為、得られる
結晶の結晶性は発光デバイスとして用いる上で不十分な
ものとなる。堆積物を除去するために成長毎に反応管を
洗浄することも考えられるがこれは生産性、安定性の点
で問題となることは明らかである。Generally, the HVPE method and the M method are used.
In vapor phase growth methods such as the OCVD method, deposits are also produced on the surface of the susceptor of the reaction tube wall during crystal growth. This deposit adversely affects foreign matter during the next crystal growth, and thus the crystallinity of the obtained crystal is insufficient for use as a light emitting device. It is possible to clean the reaction tube after each growth to remove the deposits, but it is clear that this is a problem in terms of productivity and stability.
【０００７】従って生産性、製品物性の安定性を損なわ
ず再現性良く結晶性の高い結晶を成長することは難し
く、このため得られる結晶性は発光デバイスとして用い
るには不十分なものであった。本発明の目的は、生産
性、製品物性の安定性を損なわず再現性良く、結晶性及
び表面モルフォロジーの優れたエピタキシャル結晶を得
る３−５族化合物半導体結晶の製造方法を提供すること
にある。Therefore, it is difficult to grow a crystal with high reproducibility and high crystallinity without impairing the stability of productivity and physical properties of products, and thus the crystallinity obtained is insufficient for use as a light emitting device. . An object of the present invention is to provide a method for producing a Group 3-5 compound semiconductor crystal, which obtains an epitaxial crystal having excellent reproducibility and excellent crystallinity and surface morphology without impairing the stability of productivity and product physical properties.
【０００８】[0008]
【課題を解決するための手段】本発明者らは、鋭意検討
した結果、窒化ガリウム系化合物半導体の結晶成長開始
前にエッチングガスを反応管へ導入し、基板や反応管を
気相エッチングした後、そのまま結晶成長を行うことに
より、前記の問題点を解決できることを見出し本発明に
到達した。Means for Solving the Problems As a result of intensive studies, the present inventors have found that after an etching gas is introduced into a reaction tube before the crystal growth of a gallium nitride-based compound semiconductor is started and the substrate or the reaction tube is vapor-phase etched. The inventors have found that the problems described above can be solved by performing crystal growth as it is, and arrived at the present invention.
【０００９】本発明は、分子中に少なくともＧａを有す
る３族有機金属化合物と分子中にＮを有する化合物とを
原料とし、反応管内で３−５族化合物半導体結晶を成長
させ、成長させる化合物半導体結晶とは異なる材料の基
板上に該結晶を成長させる、３族元素として少なくとも
Ｇａ、５族元素として少なくともＮを含有する３−５族
化合物半導体結晶の製造方法において、化合物半導体結
晶の成長開始前に、ハロゲン元素と５族元素を含む化合
物及びハロゲン化水素からなる群から選ばれた少なくと
も１種のガスを導入し、反応管内壁を気相エッチングす
ることを特徴とする３−５族化合物半導体結晶の製造方
法に関する。また、本発明は、分子中に少なくともＧａ
を有する３族有機金属化合物と分子中にＮを有する化合
物とを原料とし、反応管内で３−５族化合物半導体結晶
を成長させ、成長させる化合物半導体結晶とは異なる材
料の基板上にバッファー層を成長させ、その上に該結晶
を成長させる、３族元素として少なくともＧａ、５族元
素として少なくともＮを含有する３−５族化合物半導体
結晶の製造方法において、バッファー層の成長開始前
に、ハロゲン元素と５族元素を含む化合物及びハロゲン
化水素からなる群から選ばれた少なくとも１種のガスを
導入し、反応管内壁を気相エッチングすることを特徴と
する３−５族化合物半導体結晶の製造方法に関する。The present invention uses a Group 3 organometallic compound having at least Ga in the molecule and a compound having N in the molecule as raw materials to grow a Group 3-5 compound semiconductor crystal in a reaction tube and grow the compound semiconductor. In a method for producing a 3-5 group compound semiconductor crystal containing at least Ga as a group 3 element and at least N as a group 5 element, which comprises growing the crystal on a substrate made of a material different from that of the crystal, before starting the growth of the compound semiconductor crystal. To at least one gas selected from the group consisting of a compound containing a halogen element and a Group 5 element and hydrogen halide, and vapor-phase etching the inner wall of the reaction tube. The present invention relates to a method for producing crystals. The present invention also provides at least Ga in the molecule.
Using a Group 3 organometallic compound having N and a compound having N in the molecule as raw materials, grow a Group 3-5 compound semiconductor crystal in a reaction tube, and form a buffer layer on a substrate made of a material different from the compound semiconductor crystal to be grown. In a method for producing a Group 3-5 compound semiconductor crystal containing at least Ga as a Group 3 element and at least N as a Group 5 element, the halogen element is grown before starting the growth of the buffer layer. And a group 5 element-containing compound and at least one gas selected from the group consisting of hydrogen halides is introduced, and the inner wall of the reaction tube is vapor-phase etched, and a method for producing a Group 3-5 compound semiconductor crystal is characterized. Regarding
【００１０】本発明における３族元素として少なくとも
Ｇａ、５族元素として少なくともＮを含有する３−５族
化合物半導体結晶としては、ＧａＮ、ＧａX Ａｌ1-X Ｎ
（式中、０＜Ｘ＜１）、ＧａX Ｉｎ1-X Ｎ（式中、０＜
Ｘ＜１）、ＧａX ＡｌY Ｉｎ 1-X-Y Ｎ（式中、０＜Ｘ＜
１、０＜Ｙ＜１、０＜Ｘ＋Ｙ＜１）、ＧａＮY Ｐ
1-Y（式中、０＜Ｙ＜１）もしくはＧａＮY Ａｓ
1-Y （式中、０＜Ｙ＜１）又は前記の化合物半導体の少
なくとも２層の積層である化合物半導体結晶が挙げられ
る。At least the Group 3 element in the present invention
Ga 3-5 group containing at least N as a group 5 element
Compound semiconductor crystals include GaN and GaXAl1-XN
(Wherein 0 <X <1), GaXIn1-XN (where 0 <
X <1), GaXAlYIn 1-XYN (in the formula, 0 <X <
1, 0 <Y <1, 0 <X + Y <1), GaNYP
1-Y(Wherein 0 <Y <1) or GaNYAs
1-Y(In the formula, 0 <Y <1) or a small amount of the compound semiconductor
There is at least a compound semiconductor crystal which is a stack of two layers.
It
【００１１】本発明の３−５族化合物半導体結晶の製造
方法においては、分子中に少なくともＧａを有する３族
有機金属化合物と分子中にＮを有する化合物とを原料と
する。本発明における３族有機金属化合物としては、ト
リメチルガリウム、トリエチルガリウム、ジエチルガリ
ウムアジド、トリメチルアミンガラン、ジエチルガリウ
ムクロライド、トリネオペンチルガリウム、トリメチル
アルミニウム、トリエチルアルミニウム、トリメチルア
ミンアラン、トリイソブチルアルミニウム、ジメチルア
ルミニウムハイドライド、ジメチルアルミニウムクロラ
イド、トリメチルインジウム、トリエチルインジウム、
エチルジメチルインジウム、トリイソプロピルインジウ
ムなどが挙げられる。これらの中でトリメチルガリウ
ム、トリエチルガリウム、トリメチルアルミニウム、ト
リエチルアルミニウム、トリメチルインジウム、トリエ
チルインジウムが好ましい。In the method for producing a Group 3-5 compound semiconductor crystal of the present invention, a Group 3 organometallic compound having at least Ga in the molecule and a compound having N in the molecule are used as raw materials. Examples of the Group 3 organometallic compound in the present invention include trimethylgallium, triethylgallium, diethylgallium azide, trimethylamine galane, diethylgallium chloride, trineopentylgallium, trimethylaluminum, triethylaluminum, trimethylaminealane, triisobutylaluminum, dimethylaluminum hydride, Dimethyl aluminum chloride, trimethyl indium, triethyl indium,
Examples thereof include ethyl dimethyl indium and triisopropyl indium. Of these, trimethylgallium, triethylgallium, trimethylaluminum, triethylaluminum, trimethylindium and triethylindium are preferable.
【００１２】本発明における分子中に窒素原子を含有す
る化合物としては、アンモニア、ヒドラジン、メチルヒ
ドラジン、１、１−ジメチルヒドラジン、１、２−ジメ
チルヒドラジン、ｔ−ブチルアミン、エチレンジアミン
などが挙げられる。Examples of the compound containing a nitrogen atom in the molecule of the present invention include ammonia, hydrazine, methylhydrazine, 1,1-dimethylhydrazine, 1,2-dimethylhydrazine, t-butylamine and ethylenediamine.
【００１３】本発明の３−５族化合物半導体結晶の製造
方法は、反応管内で３−５族化合物半導体結晶を成長さ
せ、成長させる化合物半導体結晶とは異なる材料の基板
上に該結晶を成長させる気相成長方法である。本発明に
おける成長させる化合物半導体結晶とは異なる材料の基
板としては、具体的にはα−アルミナ基板、炭化珪素基
板又はシリコン基板が挙げられる。良好な品質の基板が
得られるという点でα−アルミナ基板とシリコン基板が
好ましく、格子不整合の程度がより小さいという点でα
−アルミナ基板が好ましい。In the method for producing a Group 3-5 compound semiconductor crystal of the present invention, a Group 3-5 compound semiconductor crystal is grown in a reaction tube, and the crystal is grown on a substrate made of a material different from the compound semiconductor crystal to be grown. It is a vapor growth method. Specific examples of the substrate of a material different from the compound semiconductor crystal to be grown in the present invention include an α-alumina substrate, a silicon carbide substrate or a silicon substrate. The α-alumina substrate and the silicon substrate are preferable in that a substrate of good quality can be obtained, and α is preferable in that the degree of lattice mismatch is smaller.
-Alumina substrates are preferred.
【００１４】本発明におけるハロゲン元素と５族元素を
含む化合物としては、三塩化砒素、三塩化リンなどが挙
げられる。ハロゲン化水素としては、塩化水素、臭化水
素、ヨウ化水素が挙げられる。これらのガスの中では塩
化水素が好ましい。本発明におけるハロゲン元素と５族
元素を含む化合物は、高温で反応管内壁に堆積した３−
５族化合物半導体又はその分解生成物などを分解するの
で、好ましいエッチング効果が得られるものと考えられ
る。このようにして、反応管内壁を気相エッチングして
から基板をサセプタに搭載して結晶成長させることがで
きる。また、ハロゲン元素と５族元素を含む化合物は、
α−アルミナ、炭化珪素又はシリコンに対しては反応性
が低いので、基板をサセプタに搭載したままエッチング
しても好ましいエッチング効果が得られるものと考えら
れ、反応管内壁と基板を気相エッチングするのは、生産
性が向上するので好ましい。Examples of the compound containing a halogen element and a Group 5 element in the present invention include arsenic trichloride and phosphorus trichloride. Examples of the hydrogen halide include hydrogen chloride, hydrogen bromide and hydrogen iodide. Of these gases, hydrogen chloride is preferred. The compound containing a halogen element and a Group 5 element in the present invention is deposited on the inner wall of the reaction tube at a high temperature.
Since a Group 5 compound semiconductor or a decomposition product thereof is decomposed, it is considered that a preferable etching effect can be obtained. In this manner, the inner wall of the reaction tube can be vapor-phase etched, and then the substrate can be mounted on the susceptor for crystal growth. Further, the compound containing a halogen element and a Group 5 element is
Since it has low reactivity with α-alumina, silicon carbide or silicon, it is thought that a preferable etching effect can be obtained even when the substrate is mounted on the susceptor, and the inner wall of the reaction tube and the substrate are vapor-phase etched. Is preferable because productivity is improved.
【００１５】本発明において気相エッチングする反応管
内壁とは、反応管の内壁全体でなくてもよく、基板を搭
載するサセプタの表面及びその周辺の反応管内壁並びに
気流の上流側の反応管内壁などを意味する。さらに具体
的には、基板の上流側に気流を適切に基板上に導くため
の吹きつけ管などを設けたときは、これらの表面をも意
味する。本発明における気相エッチングについては、反
応管内壁にさらに加えて基板を気相エッチングすること
が好ましい。本発明におけるバッファー層としては、Ｇ
ａZ Ａｌ1-Z Ｎ（式中、０≦Ｚ≦１）またはＺｎＯから
選ばれたものからなる層が挙げられる。ＧａZ Ａｌ1-Z
Ｎからなるバッファー層は、公知の成長方法によって製
造される。該バッファー層の成長温度は、３００〜８０
０℃が好ましく、４００〜７００℃がさらに好ましく、
５００〜６５０℃が特に好ましい。バッファー層の成長
温度が３００℃より低い場合は成長速度が遅くなり実用
的でなく、８００℃より高い場合は、バッファー層とし
ての効果が顕著でなくなるので好ましくない。該バッフ
ァー層の膜厚は、１００〜１０００Åが好ましく、２０
０〜８００Åがさらに好ましい。膜厚が１００Åより小
さい場合にはバッファー層の効果が顕著でなく、１００
０Åより大きい場合には、かえって効果が損なわれるの
で好ましくない。また、ＺｎＯからなるバッファー層
は、例えばα−アルミナを基板としてＺｎＯのＭＯＣＶ
Ｄによる成長法によって製造される。具体的には、ジエ
チル亜鉛〔（Ｃ2 Ｈ5 ）2 Ｚｎ〕などの有機金属化合物
と、水蒸気、炭酸ガス、Ｎ2 Ｏなどの酸素を含む化合物
を原料として用いる方法が挙げられる。該バッファー層
の成長温度は、４００〜８００℃が好ましく、該バッフ
ァー層の膜厚は、５０Å〜３μｍが好ましい。In the present invention, the inner wall of the reaction tube for vapor phase etching does not have to be the entire inner wall of the reaction tube, but the surface of the susceptor on which the substrate is mounted, the inner wall of the reaction tube on the periphery thereof, and the inner wall of the reaction tube on the upstream side of the air flow. And so on. More specifically, when a blowing tube or the like for appropriately guiding the airflow onto the substrate is provided on the upstream side of the substrate, these surfaces are also meant. Regarding the vapor phase etching in the present invention, it is preferable that the substrate is vapor phase etched in addition to the inner wall of the reaction tube. As the buffer layer in the present invention, G
(wherein, 0 ≦ Z ≦ 1) a Z Al 1-Z N include or layer made of one selected from ZnO. Ga Z Al 1-Z
The buffer layer made of N is manufactured by a known growth method. The growth temperature of the buffer layer is 300-80.
0 degreeC is preferable, 400-700 degreeC is more preferable,
500-650 degreeC is especially preferable. When the growth temperature of the buffer layer is lower than 300 ° C., the growth rate becomes slow and not practical, and when it is higher than 800 ° C., the effect as the buffer layer becomes unnoticeable, which is not preferable. The thickness of the buffer layer is preferably 100 to 1000Å, 20
0 to 800Å is more preferable. When the film thickness is less than 100Å, the effect of the buffer layer is not remarkable and
When it is larger than 0Å, the effect is rather deteriorated, which is not preferable. The buffer layer made of ZnO has a MOCV of ZnO using α-alumina as a substrate, for example.
It is manufactured by the growth method according to D. Specifically, a method of using as a raw material an organometallic compound such as diethylzinc [(C 2 H 5 ) 2 Zn] and a compound containing oxygen such as water vapor, carbon dioxide gas, and N 2 O is used. The growth temperature of the buffer layer is preferably 400 to 800 ° C., and the film thickness of the buffer layer is preferably 50Å to 3 μm.
【００１６】本発明の３−５族化合物半導体結晶の製造
方法を具体的に説明する。反応管にα−アルミナ、炭化
珪素又はシリコン等の成長させる化合物半導体膜とは異
なる材料の基板をセット後、水素等のキャリアガスを流
し、加熱した状態で、ハロゲン元素と５族元素を含む化
合物及びハロゲン化水素からなる群から選ばれた少なく
とも１種以上のガスを導入する。該ガスにより分解され
た堆積物は、キャリアガスとともに排気される。その後
結晶成長を行うことで、堆積物による結晶性の低下はな
くなり、良好な単結晶が得られる。The method for producing a Group 3-5 compound semiconductor crystal of the present invention will be specifically described. After setting a substrate made of a material different from the compound semiconductor film, such as α-alumina, silicon carbide or silicon, to be grown in the reaction tube, a carrier gas such as hydrogen is caused to flow, and a compound containing a halogen element and a Group 5 element in a heated state. And at least one gas selected from the group consisting of hydrogen halide. The deposit decomposed by the gas is exhausted together with the carrier gas. After that, by performing crystal growth, deterioration of crystallinity due to deposits is eliminated, and a good single crystal can be obtained.
【００１７】次に、具体的に本発明においてバッファー
層を用いる３−５族化合物半導体結晶の製造方法を例示
する。 １．（エッチング）水素を供給しながら洗浄した基板を
１０００〜１２００℃まで加熱し、塩化水素ガスを供給
して反応炉および基板をエッチングする。エッチング終
了後５〜１０分保持する。 ２．（バッファ層成長）基板温度を５００〜６００℃ま
で下げ、アンモニアとトリメチルガリウム（以下、ＴＭ
Ｇと記すことがある）を供給し、３００〜５００ÅのＧ
ａＮバッファ層を形成する。 ３．（昇温）ＴＭＧの供給を停止し、成長温度（８００
〜１２００℃）まで昇温する。 ４．（本成長）トリメチルガリウムを供給し、３μｍ厚
み程度のＧａＮ層を形成する。 ５．（冷却）ＴＭＧの供給、基板の加熱を停止し、基板
温度が６００℃程度まで下がったらアンモニアの供給を
停止する。Next, a method for manufacturing a Group 3-5 compound semiconductor crystal using a buffer layer in the present invention will be specifically illustrated. 1. (Etching) The substrate washed while supplying hydrogen is heated to 1000 to 1200 ° C., and hydrogen chloride gas is supplied to etch the reaction furnace and the substrate. Hold for 5 to 10 minutes after completion of etching. 2. (Buffer layer growth) The substrate temperature is lowered to 500 to 600 ° C., and ammonia and trimethylgallium (hereinafter, TM
(Sometimes referred to as G), and G of 300 to 500Å
An aN buffer layer is formed. 3. (Temperature increase) TMG supply is stopped and growth temperature (800
Up to 1200 ° C). 4. (Main growth) Trimethylgallium is supplied to form a GaN layer having a thickness of about 3 μm. 5. (Cooling) The supply of TMG and the heating of the substrate are stopped, and when the substrate temperature drops to about 600 ° C., the supply of ammonia is stopped.
【００１８】[0018]
【実施例】以下、本発明を具体的な実施例に基づいて説
明する。なお、本発明はこれらに限定されるものではな
い。 実施例１ 図１に本発明の３−５族化合物半導体結晶の製造方法で
用いる装置の一例の概略図を示す。α−アルミナ基板が
カーボンサセプタ上に載せられ、反応管外側に巻かれた
コイルによる高周波誘導加熱で温度コントロールを行っ
た。次に窒化ガリウム系化合物半導体の結晶成長工程に
ついて示す。 １．反応管サセプタ上に洗浄されたα−アルミナ基板を
セットし、反応管内を真空排気した後水素で置換した。 ２．ガス導入管１より水素を２リットル／分で供給しな
がら、高周波誘導加熱により基板温度を１１００℃まで
加熱した。 ３．ガス導入管２より１０％に水素希釈した塩化水素ガ
スを１００ｃｃ／分で導入した。 ４．この状態を５、１０、１５又は２０分保持し、反応
管等の堆積物を気相反応によって除去した。 ５．ガス導入管２からの塩化水素ガスの供給を中止し、
水素雰囲気中で５分間保持し、α−アルミナ基板表面を
改質した。 ６．基板温度を６００℃まで下げ、２リットル／分の水
素ガスに加え、ガス導入管１から２リットル／分のアン
モニアガス及び７×１０-6モル／分のトリメチルガリウ
ムガスを供給し、膜厚約５００ÅのＧａＮバッファ層を
形成した。 ７．ＴＭＧガスの供給のみを止め、基板の温度を１１０
０℃まで上昇させた。 ８．次に４．５×１０-5モル／分のトリメチルガリウム
ガスをガス導入管１から供給し、膜厚３μｍのＧａＮエ
ピタキシャル層を成長させた。 以上の工程によってエピタキシャル成長させたＧａＮ結
晶の室温での移動度をホール効果測定法によって評価し
た。結果を図２に示す。EXAMPLES The present invention will be described below based on specific examples. The present invention is not limited to these. Example 1 FIG. 1 shows a schematic view of an example of an apparatus used in the method for producing a 3-5 group compound semiconductor crystal of the present invention. The α-alumina substrate was placed on the carbon susceptor, and the temperature was controlled by high-frequency induction heating using a coil wound outside the reaction tube. Next, a crystal growth process of a gallium nitride-based compound semiconductor will be described. 1. The cleaned α-alumina substrate was set on the reaction tube susceptor, and the inside of the reaction tube was evacuated and then replaced with hydrogen. 2. The substrate temperature was raised to 1100 ° C. by high frequency induction heating while supplying hydrogen at 2 liter / min from the gas introduction pipe 1. 3. Hydrogen chloride gas diluted with hydrogen to 10% was introduced from the gas introduction pipe 2 at 100 cc / min. 4. This state was maintained for 5, 10, 15 or 20 minutes, and the deposits on the reaction tube and the like were removed by a gas phase reaction. 5. Stop the supply of hydrogen chloride gas from the gas introduction pipe 2,
The surface of the α-alumina substrate was modified by holding it in a hydrogen atmosphere for 5 minutes. 6. The substrate temperature is lowered to 600 ° C., 2 liter / min of hydrogen gas is added, 2 liter / min of ammonia gas and 7 × 10 −6 mol / min of trimethylgallium gas are supplied from the gas introduction pipe 1, and the film thickness is about A 500 Å GaN buffer layer was formed. 7. Stop the supply of TMG gas only and set the substrate temperature to 110
Raised to 0 ° C. 8. Next, 4.5 × 10 −5 mol / min of trimethylgallium gas was supplied from the gas introduction tube 1 to grow a GaN epitaxial layer having a film thickness of 3 μm. The mobility at room temperature of the GaN crystal epitaxially grown by the above steps was evaluated by the Hall effect measuring method. The results are shown in Figure 2.
【００１９】比較例１ 実施例１の結晶成長工程の３項の塩化水素ガスを導入す
ることを除いて、他は実施例１に準じてＧａＮエピタキ
シャル層を成長させた。実施例１と同様にＧａＮ結晶の
室温での移動度をホール効果測定法によって評価した。
結果を図２（エッチング時間０分に記載）に示す。一般
にノンドープ成長層では移動度が大きいほど結晶性がよ
いことがわかる。本発明により得られたＧａＮ化合物半
導体結晶では塩化水素ガスでエッチング処理した場合、
移動度が２００ｃｍ2 ／Ｖｓを超えるものが得られ、エ
ッチング時間が長くなるにつれて移動度は低下する傾向
が見られるが、それでも塩化水素ガスによるエッチング
を行わない場合の１００ｃｍ2 ／Ｖｓに比べて大きく結
晶性が向上していることがわかる。また表面モルフォロ
ジーに関しても、塩化水素ガスによる熱処理で平坦性が
飛躍的に向上した。Comparative Example 1 A GaN epitaxial layer was grown in the same manner as in Example 1 except that hydrogen chloride gas was introduced in the item 3 of the crystal growth step of Example 1. In the same manner as in Example 1, the mobility of the GaN crystal at room temperature was evaluated by the Hall effect measuring method.
The results are shown in FIG. 2 (etching time 0 minutes). It is generally understood that the higher the mobility, the better the crystallinity in the non-doped growth layer. When the GaN compound semiconductor crystal obtained by the present invention is etched with hydrogen chloride gas,
A mobility of more than 200 cm 2 / Vs is obtained, and the mobility tends to decrease as the etching time increases, but it is still higher than 100 cm 2 / Vs when etching with hydrogen chloride gas is not performed. It can be seen that the crystallinity is improved. Regarding the surface morphology, the flatness was dramatically improved by the heat treatment with hydrogen chloride gas.
【００２０】実施例２ 実施例１に記載の窒化ガリウム結晶成長において、３か
ら５の工程を以下のように変更し結晶成長を行った。１
１００℃、水素雰囲気中で５分間保持し、その後１０％
に希釈した塩化水素ガスをガス導入管２より１００ｃｃ
／分で導入し１分間保持する。塩化水素ガスの導入を中
止し、再び水素雰囲気中で５分間保持する。以上の工程
によるエピタキシャル成長により、再現性よく安定して
表面モルフォロジーのよいＧａＮ結晶が得られた。Example 2 In the gallium nitride crystal growth described in Example 1, the steps 3 to 5 were changed as follows to carry out the crystal growth. 1
Hold at 100 ℃ in hydrogen atmosphere for 5 minutes, then 10%
Hydrogen chloride gas diluted to 100 cc from the gas inlet pipe 2
/ Min and hold for 1 minute. The introduction of hydrogen chloride gas is stopped, and the atmosphere is maintained again for 5 minutes in a hydrogen atmosphere. By the epitaxial growth through the above steps, a GaN crystal with good reproducibility and stable surface morphology was obtained.
【００２１】実施例３ バッファ層として、トリメチルガリウムのかわりにトリ
メチルアルミニウムを用いてＡｌＮ層を成長させたこと
以外を除いては、実施例１と同様の手順によりエピタキ
シャル成長を行なった。以上の工程によるエピタキシャ
ル成長によっても、再現性良く安定して結晶性と表面モ
ルフォロジーの良いＧａＮ結晶が得られた。Example 3 Epitaxial growth was carried out in the same procedure as in Example 1 except that an AlN layer was grown using trimethylaluminum instead of trimethylgallium as the buffer layer. Also by the epitaxial growth by the above steps, a GaN crystal having good reproducibility and stable crystallinity and surface morphology was obtained.
【００２２】実施例４ 実施例１、２又は３の窒化ガリウム結晶成長において、
基板として炭化珪素を用いても、同様に結晶性と表面モ
ルフォロジーのよい結晶が得られる。Example 4 In the gallium nitride crystal growth of Example 1, 2 or 3,
Even if silicon carbide is used as the substrate, a crystal having good crystallinity and surface morphology can be obtained.
【００２３】実施例５ 実施例１、２又は３の窒化ガリウム結晶成長において、
基板としてシリコンを用いても、同様に結晶性と表面モ
ルフォロジーのよい結晶が得られる。Example 5 In the gallium nitride crystal growth of Example 1, 2 or 3,
Even if silicon is used as the substrate, a crystal having good crystallinity and surface morphology can be obtained.
【００２４】[0024]
【発明の効果】本発明の化合物半導体結晶の製造方法に
よれば、反応管内壁又は反応管内壁と基板の堆積物を除
去することで従来に比べて、生産性、製品物性の安定性
を損なわず、再現性良く結晶性及び表面モルフォロジー
の優れたエピタキシャル結晶層を得ることができる。本
発明の化合物半導体結晶の製造方法により得られた、３
族元素として少なくともＧａ、５族元素として少なくと
もＮを含有する３−５族化合物半導体結晶は良好な発光
素子材料として用いることができる。According to the method for producing a compound semiconductor crystal of the present invention, the deposits on the inner wall of the reaction tube or on the inner wall of the reaction tube and the substrate are removed, so that the productivity and the stability of the physical properties of the product are impaired as compared with the prior art. Therefore, an epitaxial crystal layer having good reproducibility and excellent crystallinity and surface morphology can be obtained. 3 obtained by the method for producing a compound semiconductor crystal of the present invention
A Group 3-5 compound semiconductor crystal containing at least Ga as a group element and at least N as a group 5 element can be used as a good light emitting element material.
【図１】３−５族化合物半導体結晶の製造方法において
用いる装置の概略図。FIG. 1 is a schematic view of an apparatus used in a method for producing a Group 3-5 compound semiconductor crystal.
【図２】基板のエッチング時間と移動度の関係を示す
図。FIG. 2 is a diagram showing a relationship between substrate etching time and mobility.
１・・・ガス導入管１ ２・・・ガス導入管２ ３・・・反応管 ４・・・サセプタ ５・・・基板 ６・・・真空ポンプ 1 ... Gas introduction pipe 1 2 ... Gas introduction pipe 2 3 ... Reaction pipe 4 ... Susceptor 5 ... Substrate 6 ... Vacuum pump
Claims (6)
金属化合物と分子中にＮを有する化合物とを原料とし、
反応管内で３−５族化合物半導体結晶を成長させ、成長
させる化合物半導体結晶とは異なる材料の基板上に該結
晶を成長させる、３族元素として少なくともＧａ、５族
元素として少なくともＮを含有する３−５族化合物半導
体結晶の製造方法において、化合物半導体結晶の成長開
始前に、ハロゲン元素と５族元素を含む化合物及びハロ
ゲン化水素からなる群から選ばれた少なくとも１種のガ
スを導入し、反応管内壁を気相エッチングすることを特
徴とする３−５族化合物半導体結晶の製造方法。1. A raw material of a Group 3 organometallic compound having at least Ga in the molecule and a compound having N in the molecule,
Growing a Group 3-5 compound semiconductor crystal in a reaction tube and growing the crystal on a substrate made of a material different from the compound semiconductor crystal to be grown. Containing at least Ga as a Group 3 element and at least N as a Group 5 element 3. In the method for producing a Group 5 compound semiconductor crystal, at least one gas selected from the group consisting of a compound containing a halogen element and a Group 5 element and hydrogen halide is introduced before the growth of the compound semiconductor crystal, and the reaction is performed. A method for producing a 3-5 group compound semiconductor crystal, characterized in that the inner wall of the tube is vapor-phase etched.
金属化合物と分子中にＮを有する化合物とを原料とし、
反応管内で３−５族化合物半導体結晶を成長させ、成長
させる化合物半導体結晶とは異なる材料の基板上にバッ
ファー層を成長させ、その上に該結晶を成長させる、３
族元素として少なくともＧａ、５族元素として少なくと
もＮを含有する３−５族化合物半導体結晶の製造方法に
おいて、バッファー層の成長開始前に、ハロゲン元素と
５族元素を含む化合物及びハロゲン化水素からなる群か
ら選ばれた少なくとも１種のガスを導入し、反応管内壁
を気相エッチングすることを特徴とする３−５族化合物
半導体結晶の製造方法。2. A raw material is a Group 3 organometallic compound having at least Ga in the molecule and a compound having N in the molecule,
Growing a Group 3-5 compound semiconductor crystal in a reaction tube, growing a buffer layer on a substrate made of a material different from that of the compound semiconductor crystal to be grown, and growing the crystal thereon.
In a method for producing a 3-5 group compound semiconductor crystal containing at least Ga as a group element and at least N as a group 5 element, a compound containing a halogen element and a group 5 element and hydrogen halide are included before the start of growth of a buffer layer. A method for producing a Group 3-5 compound semiconductor crystal, which comprises introducing at least one gas selected from the group and vapor-phase etching the inner wall of the reaction tube.
中、０≦Ｚ≦１）またはＺｎＯから選ばれたものからな
ることを特徴とする請求項２記載の３−５族化合物半導
体結晶の製造方法。3. The 3-5 group compound according to claim 2, wherein the buffer layer is made of Ga Z Al 1 -Z N (wherein 0 ≦ Z ≦ 1) or ZnO. Method for manufacturing semiconductor crystal.
えて基板を気相エッチングすることを特徴とする３−５
族化合物半導体結晶の製造方法。4. The method according to claim 1, wherein the substrate is vapor-phase etched in addition to the inner wall of the reaction tube.
Method for producing group compound semiconductor crystal.
えて基板を気相エッチングすることを特徴とする３−５
族化合物半導体結晶の製造方法。5. The method according to claim 2, wherein the substrate is vapor-phase etched in addition to the inner wall of the reaction tube.
Method for producing group compound semiconductor crystal.
ｌ1-X Ｎ（式中、０＜Ｘ＜１）、ＧａX Ｉｎ1-X Ｎ（式
中、０＜Ｘ＜１）、ＧａX ＡｌY Ｉｎ1-X-YＮ（式中、
０＜Ｘ＜１、０＜Ｙ＜１、０＜Ｘ＋Ｙ＜１）、ＧａＮY
Ｐ1-Y （式中、０＜Ｙ＜１）もしくはＧａＮY Ａｓ1-Y
（式中、０＜Ｙ＜１）又は前記の化合物半導体の少なく
とも２層の積層であることを特徴とする請求項１ないし
５のいずれかに記載の３−５族化合物半導体結晶の製造
方法。6. The compound semiconductor of Group 3-5 is GaN, Ga x A.
l 1-X N (in the formula, 0 <X <1), Ga X In 1-X N (in the formula, 0 <X <1), Ga X Al Y In 1-XY N (in the formula,
0 <X <1, 0 <Y <1, 0 <X + Y <1), GaN Y
P 1-Y (where 0 <Y <1) or GaN Y As 1-Y
(In the formula, 0 <Y <1) or a laminate of at least two layers of the compound semiconductor, and the method for producing a Group 3-5 compound semiconductor crystal according to any one of claims 1 to 5.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP31967294A JP3673541B2 (en) | 1993-12-22 | 1994-12-22 | Method for producing group 3-5 compound semiconductor crystal |
Applications Claiming Priority (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP32533393 | 1993-12-22 | ||
| JP30602794 | 1994-12-09 | ||
| JP5-325333 | 1994-12-09 | ||
| JP6-306027 | 1994-12-09 | ||
| JP31967294A JP3673541B2 (en) | 1993-12-22 | 1994-12-22 | Method for producing group 3-5 compound semiconductor crystal |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2002126237A Division JP3770199B2 (en) | 1993-12-22 | 2002-04-26 | Method for producing group 3-5 compound semiconductor crystal |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH08213326A true JPH08213326A (en) | 1996-08-20 |
| JP3673541B2 JP3673541B2 (en) | 2005-07-20 |
Family
ID=27338806
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP31967294A Expired - Lifetime JP3673541B2 (en) | 1993-12-22 | 1994-12-22 | Method for producing group 3-5 compound semiconductor crystal |
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| Country | Link |
|---|---|
| JP (1) | JP3673541B2 (en) |
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
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| JPH08264836A (en) * | 1995-03-27 | 1996-10-11 | Sumitomo Electric Ind Ltd | Light emitting compound semiconductor element and manufacture thereof |
| JPH08264835A (en) * | 1995-03-27 | 1996-10-11 | Sumitomo Electric Ind Ltd | Light emitting compound semiconductor element and manufacture thereof |
| KR100304664B1 (en) * | 1999-02-05 | 2001-09-26 | 윤종용 | Method for fabricating a GaN film |
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Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
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| JPH08264836A (en) * | 1995-03-27 | 1996-10-11 | Sumitomo Electric Ind Ltd | Light emitting compound semiconductor element and manufacture thereof |
| JPH08264835A (en) * | 1995-03-27 | 1996-10-11 | Sumitomo Electric Ind Ltd | Light emitting compound semiconductor element and manufacture thereof |
| KR100450785B1 (en) * | 1997-12-23 | 2004-11-16 | 삼성전기주식회사 | Method of manufacturing GaN thick film |
| US6528394B1 (en) | 1999-02-05 | 2003-03-04 | Samsung Electronics Co., Ltd. | Growth method of gallium nitride film |
| KR100304664B1 (en) * | 1999-02-05 | 2001-09-26 | 윤종용 | Method for fabricating a GaN film |
| US6569238B2 (en) | 2000-05-31 | 2003-05-27 | Matsushita Electric Industrial Co., Ltd. | Apparatus and method for depositing semi conductor film |
| KR100477075B1 (en) * | 2002-01-14 | 2005-03-17 | 엘지이노텍 주식회사 | Nitride semiconductor fabrication method |
| JP2004128504A (en) * | 2002-09-30 | 2004-04-22 | Agilent Technol Inc | Highly efficient semiconductor laser manufacturing system and method using precursor having direct bonding between group iii atom and nitrogen atom |
| JP2007176777A (en) * | 2005-12-28 | 2007-07-12 | Mitsubishi Chemicals Corp | METHOD FOR PRODUCING Ga-CONTAINING NITRIDE SEMICONDUCTOR |
| JP2007320811A (en) * | 2006-06-01 | 2007-12-13 | Mitsubishi Chemicals Corp | Method for producing nitride semiconductor substrate |
| JP4665837B2 (en) * | 2006-06-01 | 2011-04-06 | 三菱化学株式会社 | Manufacturing method of nitride semiconductor substrate |
| JP2013187366A (en) * | 2012-03-08 | 2013-09-19 | Hitachi Cable Ltd | Nitride semiconductor manufacturing method |
| JP2016171171A (en) * | 2015-03-12 | 2016-09-23 | 新日鐵住金株式会社 | Method for producing silicon carbide single crystal substrate |
| JPWO2021117728A1 (en) * | 2019-12-09 | 2021-06-17 | ||
| WO2021117728A1 (en) * | 2019-12-09 | 2021-06-17 | 株式会社Ｋｏｋｕｓａｉ Ｅｌｅｃｔｒｉｃ | Semiconductor device manufacturing method, substrate treatment device, and program |
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