JP2006062931A - Sapphire substrate and its heat treatment method, and method of crystal growth - Google Patents

Sapphire substrate and its heat treatment method, and method of crystal growth Download PDF

Info

Publication number
JP2006062931A
JP2006062931A JP2004250092A JP2004250092A JP2006062931A JP 2006062931 A JP2006062931 A JP 2006062931A JP 2004250092 A JP2004250092 A JP 2004250092A JP 2004250092 A JP2004250092 A JP 2004250092A JP 2006062931 A JP2006062931 A JP 2006062931A
Authority
JP
Japan
Prior art keywords
sapphire substrate
heat treatment
main surface
treatment method
nitride
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
Application number
JP2004250092A
Other languages
Japanese (ja)
Inventor
Michinobu Tsuda
道信 津田
Motoaki Iwatani
素顕 岩谷
Satoshi Kamiyama
智 上山
Hiroshi Amano
浩 天野
Isamu Akasaki
勇 赤崎
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Kyocera Corp
Original Assignee
Kyocera Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Kyocera Corp filed Critical Kyocera Corp
Priority to JP2004250092A priority Critical patent/JP2006062931A/en
Publication of JP2006062931A publication Critical patent/JP2006062931A/en
Pending legal-status Critical Current

Links

Images

Landscapes

  • Crystals, And After-Treatments Of Crystals (AREA)
  • Semiconductor Lasers (AREA)

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that it is difficult to obtain a high quality epitaxial thin film by a sapphire substrate (0001) used conventionally because the surface begins to roughen by a thermal treatment in a hydrogen atmosphere before epitaxial growth of a crystal. <P>SOLUTION: The sapphire substrate has a principal surface which is a surface (11-20), wherein a thermal treatment in a hydrogen atmosphere is given to the above principal surface for which surface planarization is performed by grinding. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

本発明は、窒化物系半導体を成長させるためのサファイア基板、その熱処理方法、及び、窒化物系半導体の結晶成長方法に関するものである。   The present invention relates to a sapphire substrate for growing a nitride semiconductor, a heat treatment method therefor, and a crystal growth method for a nitride semiconductor.

窒化アルミニウム（以下、ＡｌＮという。）、窒化ガリウム（以下、ＧａＮという。）、窒化インジウム（以下、ＩｎＮという。）、あるいは、それらの混晶である窒化アルミニウムガリウムインジウム（以下、ＡｌｘＧａ１−ｘ−ｙＩｎｙＮ（0≦x,y、0≦x+y≦1）という。）などの窒化物系半導体は受発光素子や電子走行素子に用いることができるため、近年、その結晶成長や半導体装置への応用について、幅広く研究がなされている。 Aluminum nitride (hereinafter referred to as AlN), gallium nitride (hereinafter referred to as GaN), indium nitride (hereinafter referred to as InN), or a mixed crystal of them, aluminum gallium indium nitride (hereinafter referred to as Al x Ga 1−). Since nitride-based semiconductors such as xy In y N (0 ≦ x, y, 0 ≦ x + y ≦ 1) can be used for light emitting / receiving devices and electron transit devices, their crystal growth has recently been increased. In addition, extensive research has been conducted on application to semiconductor devices.

窒化物系半導体は大型のバルク単結晶が成長できないため、一般的にはサファイアなどの異種基板を半導体成長用基板に用いてヘテロエピタキシャル成長させている。エピタキシャル成長の方法としては、有機金属気相成長(ＭＯＶＰＥ) 法、分子線エピタキシー(ＭＢＥ)法、ハライド気相成長(ＨＶＰＥ)法などがあるが、実用化の面で最も一般的なのはＭＯＶＰＥ法である。   Since nitride-based semiconductors cannot grow large bulk single crystals, they are generally heteroepitaxially grown using a heterogeneous substrate such as sapphire as a substrate for semiconductor growth. Epitaxial growth methods include metalorganic vapor phase epitaxy (MOVPE), molecular beam epitaxy (MBE), and halide vapor phase epitaxy (HVPE). The most common method for practical use is MOVPE. .

サファイア基板は、窒化物系半導体のみならず、その他の半導体材料や超伝導材料など、様々な材料の薄膜を堆積するために、広く用いられる。   Sapphire substrates are widely used for depositing thin films of various materials such as nitride semiconductors, other semiconductor materials, and superconducting materials.

元来、サファイア基板は、特定の結晶面を表面に露出させた後、機械研磨、及び化学機械研磨によって鏡面状態に研磨され、この上に素子構造を成長させる。従って、サファイア基板は表面形態が不均一であってはならないが、化学機械研磨を行っただけではサファイア基板上はｎｍオーダーで表面状態に凹凸がみられる。このため、高品質の半導体を成長させる技術として、サファイア基板の主面を所定の面方位から若干ずらして作製（オフアングル）した後、何らか処理を行い、主面に微小なステップ／テラス構造を形成させることが特許文献１〜３に提案されている。ここで、ステップ／テラス構造は、図３に示すように、原子層オーダーで階段状に原子が整列してステップ１１とテラス１２が形成されている状態を指す。ステップ／テラス構造を有する基板表面に結晶薄膜をエピタキシャル成長させると、所謂ステップフロー成長が起こり、高品質な結晶が成長できる。
特開平１１−７４５６２号 特開２０００−１５９６００号 特開２００２−２９３６９２号 Originally, a sapphire substrate is exposed to a specific crystal plane on the surface, and then polished to a mirror state by mechanical polishing and chemical mechanical polishing, and an element structure is grown thereon. Therefore, the surface form of the sapphire substrate should not be non-uniform, but the surface state of the sapphire substrate is uneven in the order of nm only by chemical mechanical polishing. For this reason, as a technology for growing high-quality semiconductors, the main surface of the sapphire substrate is slightly shifted from the predetermined plane orientation (off-angle), and then some processing is performed to form a micro step / terrace structure on the main surface. It is proposed in Patent Documents 1 to 3 to form. Here, as shown in FIG. 3, the step / terrace structure indicates a state in which the steps 11 and the terrace 12 are formed by arranging atoms in a stepped manner in the atomic layer order. When a crystal thin film is epitaxially grown on the surface of a substrate having a step / terrace structure, so-called step flow growth occurs, and a high-quality crystal can be grown.
Japanese Patent Laid-Open No. 11-74562 JP 2000-159600 A JP 2002-293692 A

しかし、従来の窒化物系半導体をエピタキシャル成長には下記のような問題があり、期待されているような高品質な窒化物系半導体を得ることができなかった。   However, epitaxial growth of a conventional nitride-based semiconductor has the following problems, and a high-quality nitride-based semiconductor as expected cannot be obtained.

ＭＯＶＰＥ法による窒化物系半導体のエピタキシャル成長の場合、低温バッファ層を介して窒化物系半導体を成長させることが一般的であるが、その低温バッファ層の堆積前に、エピタキシャル成長装置内でサファイア基板を水素雰囲気中での熱処理を行う。その時の熱処理温度は１１００〜１２００℃の高温で行われる。   In the case of epitaxial growth of a nitride-based semiconductor by the MOVPE method, it is common to grow a nitride-based semiconductor through a low-temperature buffer layer. Heat treatment is performed in an atmosphere. The heat treatment temperature at that time is performed at a high temperature of 1100 to 1200 ° C.

また、サファイア基板上へ窒化物系半導体をエピタキシャル成長させる場合、主に（０００１）面が主面として用いられる。この場合、前述の熱処理による表面ラフニングの影響があり、表面粗さが増大してしまう。図４は、熱処理時間５分の場合の、熱処理温度とサファイア基板表面の二乗根平均表面粗さＲｒｍｓの関係である。Ｒｒｍｓは、原子間力顕微鏡(ＡＦＭ)で評価した。 When a nitride semiconductor is epitaxially grown on a sapphire substrate, the (0001) plane is mainly used as the main surface. In this case, there is an influence of surface roughening due to the heat treatment described above, and the surface roughness increases. FIG. 4 shows the relationship between the heat treatment temperature and the root mean square surface roughness R rms of the sapphire substrate surface when the heat treatment time is 5 minutes. R rms was evaluated with an atomic force microscope (AFM).

このため、予め何らかの処理を行ってサファイア基板の表面粗さを小さく抑えたとしても、低温バッファ層を堆積する直前のサファイア基板の表面粗さは増大してしまい、予め基板に対して行ったステップ／テラス構造の形成の効果が失われていた。しかしながら、低温バッファ層堆積前の熱処理は、その後の低温バッファ層の品質を左右する重要な工程であり省略できない。   For this reason, even if the surface roughness of the sapphire substrate is kept small by performing some kind of treatment in advance, the surface roughness of the sapphire substrate immediately before depositing the low-temperature buffer layer increases, and the steps performed on the substrate in advance / The effect of forming the terrace structure was lost. However, the heat treatment before the deposition of the low temperature buffer layer is an important process that affects the quality of the subsequent low temperature buffer layer and cannot be omitted.

同様の熱処理工程は、他の材料をサファイア基板上に形成する場合にも行われ、窒化物系半導体と同様の問題を抱えていた。   The same heat treatment process was performed when other materials were formed on the sapphire substrate, and had the same problems as the nitride-based semiconductor.

従って、水素雰囲気中での熱処理を行っても、表面粗さが増大しないようなサファイア基板や、それを用いた結晶成長方法が望まれていた。   Therefore, there has been a demand for a sapphire substrate that does not increase the surface roughness even when heat treatment is performed in a hydrogen atmosphere, and a crystal growth method using the sapphire substrate.

上記に鑑みて、本発明は、主面上に結晶成長させるためのサファイア基板において、主面が（１１−２０）面であり、研磨によって表面平坦化を行った上記主面に対し、水素雰囲気中で熱処理を施したことを特徴とする。   In view of the above, the present invention provides a sapphire substrate for crystal growth on a main surface, wherein the main surface is a (11-20) surface, and a hydrogen atmosphere is applied to the main surface subjected to surface planarization by polishing. It is characterized by being heat-treated in the inside.

また、上記主面にステップ／テラス構造が形成されていることを特徴とする。さらに、上記主面の二乗平均平方根の表面粗さが０．１ｎｍ未満であることを特徴とする。   Further, a step / terrace structure is formed on the main surface. Furthermore, the surface roughness of the root mean square of the main surface is less than 0.1 nm.

また、上記主面上にAlxGa1-x-y InyN（0≦x, y、0≦x+y≦1）で表される窒化物系半導体層を成長させることを特徴とする。 In addition, a nitride-based semiconductor layer represented by Al x Ga 1-xy In y N (0 ≦ x, y, 0 ≦ x + y ≦ 1) is grown on the main surface.

本発明は、主面が（１１−２０）面であるサファイア基板の熱処理方法において、水素雰囲気中で、熱処理温度が９００℃以上２０００℃以下であることを特徴とする。   The present invention is characterized in that in the heat treatment method for a sapphire substrate whose main surface is a (11-20) surface, the heat treatment temperature is 900 ° C. or more and 2000 ° C. or less in a hydrogen atmosphere.

また、水素を常に供給し、かつ排気しながら熱処理することを特徴とする。さらに、熱処理を行う空間の単位断面積当たりの水素流量が、５〜１００００ＳＣＣＭ／ｃｍ２であることを特徴とする。 Further, the heat treatment is performed while hydrogen is always supplied and exhausted. Furthermore, the hydrogen flow rate per unit cross-sectional area of the space for heat treatment is 5 to 10000 SCCM / cm 2 .

また、上記の熱処理方法により予め熱処理を行ったサファイア基板を用い、エピタキシャル成長装置内ではサファイア基板の熱処理を施すことなく、成長プロセスを開始する結晶成長方法を特徴とする。さらにAlxGa1-x-yIn y N（0≦x,y、0≦x+y≦1）で表される窒化物系半導体を成長させることを特徴とする。 Further, the present invention is characterized by a crystal growth method in which a sapphire substrate that has been heat-treated in advance by the above-described heat treatment method is used, and the growth process is started without performing heat treatment of the sapphire substrate in the epitaxial growth apparatus. Furthermore, a nitride semiconductor represented by Al x Ga 1-xy In y N (0 ≦ x, y, 0 ≦ x + y ≦ 1) is grown.

（１１−２０）面のサファイア基板は、（０００１）面サファイア基板とは異なり、水素雰囲気中での熱処理を行っても表面ラフニングが生じないだけでなく、表面にステップ／テラス構造を形成し得る。これにより高品質な窒化物系半導体のエピタキシャル成長が可能となる。   Unlike the (0001) plane sapphire substrate, the (11-20) plane sapphire substrate does not cause surface roughening even when heat treatment is performed in a hydrogen atmosphere, and can form a step / terrace structure on the surface. . Thereby, epitaxial growth of a high-quality nitride-based semiconductor becomes possible.

以下に、本発明の実施の形態について説明する。   Embodiments of the present invention will be described below.

本発明のサファイア基板は、（１１−２０）面を主面として用い、機械研磨や化学機械研磨によって表面平坦化を行った上記主面に対し、水素雰囲気中で熱処理を施したものである。図１にＡＦＭで評価したサファイア表面の二乗根平均表面粗さＲｒｍｓと熱処理温度との関係を示す。熱処理は水素雰囲気中で行い、温度が安定した後５分間保持した。 The sapphire substrate of the present invention is obtained by performing heat treatment in a hydrogen atmosphere on the main surface that has been subjected to surface flattening by mechanical polishing or chemical mechanical polishing using the (11-20) surface as a main surface. FIG. 1 shows the relationship between the root mean square surface roughness R rms of the sapphire surface evaluated by AFM and the heat treatment temperature. The heat treatment was performed in a hydrogen atmosphere and held for 5 minutes after the temperature was stabilized.

図４に示す（０００１）面の場合は１０００℃を超える熱処理温度では面粗さが増大していたが、図１に示す（１１−２０）面の場合は、その面粗さはほぼ一定値であった。ＡＦＭ像から、９００℃を超えると表面形態が荒れたものになる（０００１）面とは異なり、（１１−２０）面ではステップ／テラス構造が観察された。図２に、ステップ／テラス構造が形成された（１１−２０）サファイア基板の表面ＡＦＭ像を示す。   In the case of the (0001) plane shown in FIG. 4, the surface roughness increased at a heat treatment temperature exceeding 1000 ° C., but in the case of the (11-20) plane shown in FIG. Met. From the AFM image, a step / terrace structure was observed on the (11-20) plane, unlike the (0001) plane where the surface morphology became rough when it exceeded 900 ° C. FIG. 2 shows a surface AFM image of a (11-20) sapphire substrate on which a step / terrace structure is formed.

これらの結果より、本発明者らは（１１−２０）面は、水素雰囲気中での熱処理を行っても、その表面は安定しており、表面ラフニングが生じないだけでなく、表面にステップ／テラス構造が生成することを、見出した。これは、還元雰囲気である水素雰囲気中では、同じサファイア結晶であっても面方位によって熱エネルギーによる原子の挙動がことなることを示している。その理由についてはまだ明確ではないが、熱エネルギーにより、アルミニウム原子、及び、酸素原子が、共にマイグレーションしていることは確かである。   From these results, the present inventors have found that the (11-20) plane has a stable surface even when heat treatment is performed in a hydrogen atmosphere, and surface roughening does not occur. It has been found that a terrace structure is generated. This shows that in a hydrogen atmosphere, which is a reducing atmosphere, the behavior of atoms due to thermal energy differs depending on the plane orientation even for the same sapphire crystal. The reason for this is not clear yet, but it is certain that both aluminum atoms and oxygen atoms have migrated due to thermal energy.

このように、（１１−２０）面を主面とするサファイア基板に水素雰囲気中で熱処理を行うと、ステップ／テラス構造を生じるが、その時の熱処理温度は、９００℃以上でなければならない。また、ステップ高さは、０．２ｎｍ以下であり、それ以上の高さを持つステップは重合していることが多く、均一性に乏しい表面となる。   Thus, when heat treatment is performed in a hydrogen atmosphere on a sapphire substrate having a (11-20) plane as a main surface, a step / terrace structure is produced, and the heat treatment temperature at that time must be 900 ° C. or higher. Further, the step height is 0.2 nm or less, and steps having a height higher than that are often polymerized, resulting in a surface with poor uniformity.

なお、サファイアの融点が２０５３℃であるので、熱処理温度は２０００以下、好ましくは、１５００℃以下であるのが良い。   Since the melting point of sapphire is 2053 ° C., the heat treatment temperature is 2000 or less, preferably 1500 ° C. or less.

次に、本発明のサファイア基板の熱処理方法について説明する。   Next, the heat treatment method for the sapphire substrate of the present invention will be described.

まず、熱処理装置内にサファイア基板を設置し、処理室内雰囲気を真空排気した後、水素を流し続ける。水素を密閉した状態で加熱しても上記のような効果は得られないので、水素は常に供給し、かつ排気を行う。その時の水素流量は、処理室の断面積に応じて５〜１００００ＳＣＣＭ／ｃｍ２とすればよい。５ＳＣＣＭ／ｃｍ２より流量が少ないと水素雰囲気の効果が得られないし、また、１００００ＳＣＣＭ／ｃｍ２より多いと水素流量が大きすぎて排気が困難となる問題が生じる。熱処理温度は、９００℃以上２０００℃以下、好ましくは１５００℃以下であれば良い。 First, a sapphire substrate is installed in a heat treatment apparatus, and after the atmosphere in the processing chamber is evacuated, hydrogen is kept flowing. Even if hydrogen is heated in a sealed state, the above effect cannot be obtained, so hydrogen is always supplied and exhausted. The hydrogen flow rate at that time may be 5 to 10,000 SCCM / cm 2 depending on the cross-sectional area of the processing chamber. If the flow rate is less than 5 SCCM / cm 2 , the effect of the hydrogen atmosphere cannot be obtained, and if it exceeds 10000 SCCM / cm 2 , the hydrogen flow rate is too large and exhausting becomes difficult. The heat treatment temperature may be 900 ° C. or higher and 2000 ° C. or lower, preferably 1500 ° C. or lower.

次に、本発明のサファイア基板を用いた結晶成長方法について説明する。水素雰囲気中の熱処理を事前に行っておけば、その後に行う結晶成長についてはエピタキシャル成長炉内では、熱処理を割愛することができる。水素熱処理の効果は、一度大気に曝しても保持される。一律な熱処理を同時に大量に行うことができるため、結晶成長の度に熱処理を行う場合に比べ、製造時間の短縮の他、品質を安定化できる。この方法は、特に、AlxGayIn1-x-yN（0≦x,y、0≦x+y≦1）で表される窒化物系半導体からなる結晶をサファイア基板上に成長させる場合は有効である。 Next, a crystal growth method using the sapphire substrate of the present invention will be described. If heat treatment in a hydrogen atmosphere is performed in advance, the subsequent crystal growth can be omitted in the epitaxial growth furnace. The effect of hydrogen heat treatment is retained even after being exposed to the atmosphere. Since uniform heat treatment can be performed in large quantities at the same time, the manufacturing time can be shortened and the quality can be stabilized as compared with the case where the heat treatment is performed every time the crystal grows. This method is particularly suitable when a crystal made of a nitride semiconductor represented by Al x Ga y In 1-xy N (0 ≦ x, y, 0 ≦ x + y ≦ 1) is grown on a sapphire substrate. It is valid.

本発明で用いるサファイア基板は、公知の結晶成長方法を用いて製造したものでよく、EFG法やチョクラルスキー法など種々の方法が挙げられる。   The sapphire substrate used in the present invention may be manufactured using a known crystal growth method, and various methods such as an EFG method and a Czochralski method may be used.

まず、（１１−２０）面を主面とするサファイア基板を、銅板を用いてダイヤモンドスラリーにより機械研磨した。その後、研磨パッドを用いてコロイダルシリカにより化学機械研磨を行った。そのサファイア基板の主面が、サファイア基板の配置用治具に触れないよう注意しつつ、熱処理装置に設置した。   First, a sapphire substrate having a (11-20) plane as a main surface was mechanically polished with diamond slurry using a copper plate. Thereafter, chemical mechanical polishing was performed with colloidal silica using a polishing pad. The main surface of the sapphire substrate was placed in a heat treatment apparatus, being careful not to touch the sapphire substrate placement jig.

次に、処理室内雰囲気を真空排気し、水素を処理室に導入した。流量２０００ＳＣＣＭの水素を流し続けた。この時の処理室の断面積が１０ｃｍ２であったので、単位断面積当たりでは、２００ＳＣＣＭ／ｃｍ２である。まず、１１５０℃まで昇温し、安定してから5分の間保持した。その後、室温まで温度を下げ、処理室内雰囲気を窒素で置換してサファイア基板を取り出した。このようにして、主面の表面部が還元されたサファイア基板を得た。室温まで冷却してサファイア基板を取り出した後、ＡＦＭにより表面形態を測定したところ、ステップ／テラス構造が形成されており、表面粗さＲｒｍｓは０．０５ｎｍであった。 Next, the atmosphere in the processing chamber was evacuated and hydrogen was introduced into the processing chamber. The flow of 2000 SCCM of hydrogen was continued. Since the cross-sectional area of the processing chamber at this time was 10 cm 2, it was 200 SCCM / cm 2 per unit cross-sectional area. First, the temperature was raised to 1150 ° C. and held for 5 minutes after stabilization. Thereafter, the temperature was lowered to room temperature, the atmosphere in the processing chamber was replaced with nitrogen, and the sapphire substrate was taken out. In this way, a sapphire substrate in which the surface portion of the main surface was reduced was obtained. After cooling to room temperature and taking out the sapphire substrate, the surface morphology was measured by AFM. As a result, a step / terrace structure was formed, and the surface roughness R rms was 0.05 nm.

以下、上記と同様な評価を、条件を変化させて比較するために、表１に示すような条件で実施例１〜６、及び、比較例１を作成して評価した。   Hereinafter, Examples 1 to 6 and Comparative Example 1 were prepared and evaluated under the conditions shown in Table 1 in order to compare the same evaluation as described above while changing the conditions.

まず、比較例１に示すように、（０００１）を主面とするサファイア基板を用いたところ、表面ラフニングが生じ、表面粗さＲｒｍｓは０．２５ｎｍであり、表面平坦性に乏しかった。 First, as shown in Comparative Example 1, when a sapphire substrate having (0001) as the main surface was used, surface roughening occurred, the surface roughness R rms was 0.25 nm, and the surface flatness was poor.

次に、熱処理温度を変化させ、（１１−２０）面を主面とするサファイア基板を熱処理したところ、すべての場合において表面粗さＲｒｍｓは０．１ｎｍ以下であった。表面形態に関しては、９００℃以上の場合においてステップ／テラス構造が観察された。 Next, when the heat treatment temperature was changed and the sapphire substrate having the (11-20) plane as the main surface was heat treated, the surface roughness R rms was 0.1 nm or less in all cases. Regarding the surface morphology, a step / terrace structure was observed in the case of 900 ° C. or higher.

別の実施例として、上記の実施例１〜６と同様の熱処理をサファイア基板上で行ったサファイア基板を用いてGaNの結晶成長を行い、評価を行った。その結果を表２に示す。実施例７〜１２に示すように、熱処理温度が８００℃の場合には、表面にピットを生じ、表面の粗い結晶が成長したが、９００℃以上では、平滑な結晶成長を行うことができた。

Figure 2006062931
Figure 2006062931
 As another example, GaN crystal growth was performed using a sapphire substrate that was subjected to the same heat treatment as in Examples 1 to 6 above, and evaluation was performed. The results are shown in Table 2. As shown in Examples 7 to 12, when the heat treatment temperature was 800 ° C., pits were generated on the surface, and a crystal with a rough surface grew, but at 900 ° C. or higher, smooth crystal growth could be performed. .
Figure 2006062931
Figure 2006062931

本発明のサファイア基板の、熱処理温度と表面粗さの関係を示す図である。It is a figure which shows the relationship between the heat processing temperature and surface roughness of the sapphire substrate of this invention. 本発明のサファイア基板の表面状態を示す図である。It is a figure which shows the surface state of the sapphire substrate of this invention. 本発明のサファイア基板のステップ／テラス構造を説明する概略図である。It is the schematic explaining the step / terrace structure of the sapphire substrate of this invention. 従来のサファイア基板の、熱処理温度と表面粗さの関係を示す図である。It is a figure which shows the relationship between the heat processing temperature and surface roughness of the conventional sapphire substrate.

符号の説明Explanation of symbols

１１ ステップ
１２ テラス 11 Step 12 Terrace

Claims (9)

主面が（１１−２０）面であり、研磨によって表面平坦化を行った上記主面に対し、水素雰囲気中で熱処理を施したことを特徴とするサファイア基板。 A sapphire substrate, wherein the main surface is a (11-20) surface, and the main surface subjected to surface planarization by polishing is heat-treated in a hydrogen atmosphere. 上記主面にステップ／テラス構造が形成されていることを特徴とする請求項１に記載のサファイア基板。 The sapphire substrate according to claim 1, wherein a step / terrace structure is formed on the main surface. 上記主面の二乗平均平方根の表面粗さが０．１ｎｍ未満であることを特徴とする請求項１〜２のいずれかに記載のサファイア基板。 3. The sapphire substrate according to claim 1, wherein a surface roughness of a root mean square of the main surface is less than 0.1 nm. 上記主面上にAlxGa1-x-y InyN（0≦x, y、0≦x+y≦1）で表される窒化物系半導体層を成長させることを特徴とする請求項１〜３のいずれかに記載のサファイア基板。 A nitride-based semiconductor layer represented by Al x Ga 1-xy In y N (0 ≦ x, y, 0 ≦ x + y ≦ 1) is grown on the main surface. 4. The sapphire substrate according to any one of 3. 主面が（１１−２０）面であるサファイア基板の熱処理方法において、水素雰囲気中で、熱処理温度が９００℃以上２０００℃以下であることを特徴とするサファイア基板の熱処理方法。 A heat treatment method for a sapphire substrate, wherein a heat treatment temperature is 900 ° C. or more and 2000 ° C. or less in a hydrogen atmosphere in a heat treatment method for a sapphire substrate whose main surface is a (11-20) surface. 水素を常に供給し、かつ排気しながら熱処理することを特徴とする請求項５記載のサファイア基板の熱処理方法。 6. The heat treatment method for a sapphire substrate according to claim 5, wherein the heat treatment is performed while hydrogen is always supplied and exhausted. 熱処理を行う空間の単位断面積当たりの水素流量が、５〜１００００ＳＣＣＭ／ｃｍ２であることを特徴とする請求項５または６記載のサファイア基板の熱処理方法。 Hydrogen flow rate per unit cross-sectional area of the space for performing the heat treatment, the heat treatment method of the sapphire substrate according to claim 5 or 6, wherein it is 5~10000SCCM / cm 2. 請求項５〜７のいずれかに記載の熱処理方法により予め熱処理を行ったサファイア基板を用い、エピタキシャル成長装置内ではサファイア基板の熱処理を施すことなく、成長プロセスを開始することを特徴とする結晶成長方法。 A crystal growth method comprising using a sapphire substrate that has been heat-treated in advance by the heat treatment method according to claim 5, and starting a growth process without performing heat treatment of the sapphire substrate in an epitaxial growth apparatus. . AlxGa1-x-yIn y N（0≦x,y、0≦x+y≦1）で表される窒化物系半導体を成長させることを特徴とする請求項８記載の結晶成長方法。 9. The crystal growth method according to claim 8, wherein a nitride-based semiconductor represented by Al x Ga 1-xy In y N (0 ≦ x, y, 0 ≦ x + y ≦ 1) is grown.
JP2004250092A 2004-08-30 2004-08-30 Sapphire substrate and its heat treatment method, and method of crystal growth Pending JP2006062931A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2004250092A JP2006062931A (en) 2004-08-30 2004-08-30 Sapphire substrate and its heat treatment method, and method of crystal growth

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2004250092A JP2006062931A (en) 2004-08-30 2004-08-30 Sapphire substrate and its heat treatment method, and method of crystal growth

Publications (1)

Publication Number Publication Date
JP2006062931A true JP2006062931A (en) 2006-03-09

Family

ID=36109726

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2004250092A Pending JP2006062931A (en) 2004-08-30 2004-08-30 Sapphire substrate and its heat treatment method, and method of crystal growth

Country Status (1)

Country Link
JP (1) JP2006062931A (en)

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2007123093A1 (en) * 2006-04-17 2007-11-01 Inter Optec Co., Ltd. Single crystal sapphire substrate
JP2008254941A (en) * 2007-04-02 2008-10-23 Sumitomo Metal Mining Co Ltd Sapphire single crystal substrate and method for manufacturing the same
US9154678B2 (en) 2013-12-11 2015-10-06 Apple Inc. Cover glass arrangement for an electronic device
US9225056B2 (en) 2014-02-12 2015-12-29 Apple Inc. Antenna on sapphire structure
US9221289B2 (en) 2012-07-27 2015-12-29 Apple Inc. Sapphire window
US9232672B2 (en) 2013-01-10 2016-01-05 Apple Inc. Ceramic insert control mechanism
WO2016153070A1 (en) * 2015-03-26 2016-09-29 京セラ株式会社 Sapphire member and method for manufacturing sapphire member
US9632537B2 (en) 2013-09-23 2017-04-25 Apple Inc. Electronic component embedded in ceramic material
US9678540B2 (en) 2013-09-23 2017-06-13 Apple Inc. Electronic component embedded in ceramic material
US10052848B2 (en) 2012-03-06 2018-08-21 Apple Inc. Sapphire laminates
JP2019046984A (en) * 2017-09-04 2019-03-22 株式会社Flosfia Method for manufacturing semiconductor device, and semiconductor device
US10406634B2 (en) 2015-07-01 2019-09-10 Apple Inc. Enhancing strength in laser cutting of ceramic components

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001185499A (en) * 2000-10-16 2001-07-06 Toyoda Gosei Co Ltd Manufacture of gallium nitride-based compound semiconductor
JP2002255694A (en) * 2001-02-26 2002-09-11 Kyocera Corp Substrate for semiconductor and producing method thereof
JP2004111848A (en) * 2002-09-20 2004-04-08 Kyocera Corp Sapphire substrate, epitaxial substrate using it, and its manufacturing method

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001185499A (en) * 2000-10-16 2001-07-06 Toyoda Gosei Co Ltd Manufacture of gallium nitride-based compound semiconductor
JP2002255694A (en) * 2001-02-26 2002-09-11 Kyocera Corp Substrate for semiconductor and producing method thereof
JP2004111848A (en) * 2002-09-20 2004-04-08 Kyocera Corp Sapphire substrate, epitaxial substrate using it, and its manufacturing method

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5129740B2 (en) * 2006-04-17 2013-01-30 株式会社 斉藤光学製作所 Single crystal sapphire substrate
WO2007123093A1 (en) * 2006-04-17 2007-11-01 Inter Optec Co., Ltd. Single crystal sapphire substrate
JP2008254941A (en) * 2007-04-02 2008-10-23 Sumitomo Metal Mining Co Ltd Sapphire single crystal substrate and method for manufacturing the same
US10052848B2 (en) 2012-03-06 2018-08-21 Apple Inc. Sapphire laminates
US9221289B2 (en) 2012-07-27 2015-12-29 Apple Inc. Sapphire window
US9232672B2 (en) 2013-01-10 2016-01-05 Apple Inc. Ceramic insert control mechanism
US9632537B2 (en) 2013-09-23 2017-04-25 Apple Inc. Electronic component embedded in ceramic material
US9678540B2 (en) 2013-09-23 2017-06-13 Apple Inc. Electronic component embedded in ceramic material
US9154678B2 (en) 2013-12-11 2015-10-06 Apple Inc. Cover glass arrangement for an electronic device
US10386889B2 (en) 2013-12-11 2019-08-20 Apple Inc. Cover glass for an electronic device
US10324496B2 (en) 2013-12-11 2019-06-18 Apple Inc. Cover glass arrangement for an electronic device
US9225056B2 (en) 2014-02-12 2015-12-29 Apple Inc. Antenna on sapphire structure
US9692113B2 (en) 2014-02-12 2017-06-27 Apple Inc. Antenna on sapphire structure
US9461357B2 (en) 2014-02-12 2016-10-04 Apple Inc. Antenna on sapphire structure
WO2016153070A1 (en) * 2015-03-26 2016-09-29 京セラ株式会社 Sapphire member and method for manufacturing sapphire member
US10406634B2 (en) 2015-07-01 2019-09-10 Apple Inc. Enhancing strength in laser cutting of ceramic components
JP2019046984A (en) * 2017-09-04 2019-03-22 株式会社Flosfia Method for manufacturing semiconductor device, and semiconductor device
JP7065440B2 (en) 2017-09-04 2022-05-12 株式会社Flosfia Manufacturing method of semiconductor device and semiconductor device

Similar Documents

Publication Publication Date Title
JP4849296B2 (en) GaN substrate
JP4581490B2 (en) III-V group nitride semiconductor free-standing substrate manufacturing method and III-V group nitride semiconductor manufacturing method
US7687824B2 (en) Method of improving surface flatness of group-III nitride crystal, substrate for epitaxial growth, and semiconductor device
JP5236148B2 (en) EPITAXIAL SUBSTRATE, SEMICONDUCTOR DEVICE, METHOD FOR MANUFACTURING EPITAXIAL SUBSTRATE, METHOD FOR MANUFACTURING SEMICONDUCTOR DEVICE, AND METHOD FOR ALIGNING DISLOCATION IN GROUP III NITRIDE CRYSTAL
JP5371430B2 (en) Semiconductor substrate, method for manufacturing a self-supporting semiconductor substrate by hydride vapor phase epitaxy, and mask layer used therefor
TWI437637B (en) Method for manufacturing gallium nitride single crystalline substrate using self-split
WO2010087518A1 (en) Epitaxial silicon carbide single crystal substrate and mehtod for producing same
GB2440484A (en) Group 3-5 nitride semiconductor multilayer substrate, method for manufacturing group 3-5 nitride semiconductor free-standing substrate
JP2008290898A (en) Low-resistivity silicon carbide single crystal substrate
JP2007197276A (en) Group iii-v nitride-based semiconductor substrate, its manufacturing method, and group iii-v nitride-based light emitting element
JP2004319711A (en) Porous substrate for epitaxial growth and its manufacturing method, and method of manufacturing group iii nitride semiconductor substrate
JP4150527B2 (en) Crystal production method
WO2012043885A1 (en) Method for producing substrate for group iii nitride semiconductor element fabrication, method for producing group iii nitride semiconductor free-standing substrate or group iii nitride semiconductor element, and group iii nitride growth substrate
JP2006062931A (en) Sapphire substrate and its heat treatment method, and method of crystal growth
JP2004111848A (en) Sapphire substrate, epitaxial substrate using it, and its manufacturing method
JP2005306680A (en) Semiconductor substrate, stand-alone substrate, and method for manufacturing these, as well as method for polishing substrate
JP2011051849A (en) Nitride semiconductor self-supporting substrate and method for manufacturing the same
JP2009023853A (en) Group iii-v nitride semiconductor substrate, method for manufacturing the same, and group iii-v nitride semiconductor device
JP2004269313A (en) Method for manufacturing gallium nitride crystal substrate
JP2009114061A (en) Method for manufacturing self-supporting substrate of group iii-v nitride-based semiconductor
JP6052465B2 (en) Method for manufacturing epitaxial silicon carbide wafer
JP2005064336A (en) Method for manufacturing group iii nitride compound semiconductor substrate
JP2005183524A (en) Epitaxial substrate and its manufacturing method, and method of reducing dislocation
JP3870259B2 (en) Nitride semiconductor laminate and growth method thereof
WO2003056073A1 (en) Group iii nitride semiconductor substrate and its manufacturing method

Legal Events

Date Code Title Description
A621 Written request for application examination

Effective date: 20070718

Free format text: JAPANESE INTERMEDIATE CODE: A621

A977 Report on retrieval

Effective date: 20090407

Free format text: JAPANESE INTERMEDIATE CODE: A971007

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20101214

A521 Written amendment

Effective date: 20110214

Free format text: JAPANESE INTERMEDIATE CODE: A523

A02 Decision of refusal

Free format text: JAPANESE INTERMEDIATE CODE: A02

Effective date: 20110426