JPH05148091A - Method for treating rutile single crystal - Google Patents
Method for treating rutile single crystalInfo
- Publication number
- JPH05148091A JPH05148091A JP31905191A JP31905191A JPH05148091A JP H05148091 A JPH05148091 A JP H05148091A JP 31905191 A JP31905191 A JP 31905191A JP 31905191 A JP31905191 A JP 31905191A JP H05148091 A JPH05148091 A JP H05148091A
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- Japan
- Prior art keywords
- single crystal
- thin film
- rutile single
- axis
- wafer
- 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.)
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- Crystals, And After-Treatments Of Crystals (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、融液、溶液、気体から
成長したルチル単結晶の品質をより向上させるための処
理方法に関するものである。TECHNICAL FIELD The present invention relates to a treatment method for further improving the quality of a rutile single crystal grown from a melt, a solution or a gas.
【０００２】[0002]
【従来の技術】方解石の代替品として、偏光プリズムな
ど高精度光学機器部品に利用されるルチル単結晶は、結
晶内でサブグレインなどの格子欠陥を発生しやすく、従
来は、単結晶育成時の条件を調節したり、その後の熱処
理を慎重に制御することで、このような格子欠陥を抑
え、高品質の結晶を得るように試みられていた。2. Description of the Related Art As a substitute for calcite, rutile single crystals used in high-precision optical equipment parts such as polarizing prisms are liable to cause lattice defects such as subgrains in the crystals, and are conventionally used during single crystal growth. Attempts have been made to suppress such lattice defects and obtain high quality crystals by adjusting the conditions and carefully controlling the subsequent heat treatment.
【０００３】[0003]
【発明が解決しようとする課題】しかしながら、従来行
われてきたやり方では、単結晶中の格子欠陥を完全に除
去することができていない。However, the conventional method cannot completely remove the lattice defects in the single crystal.
【０００４】本発明は、このような事情に鑑みてなされ
たもので、格子欠陥のない高品質のルチル単結晶を効率
よく得ることができるルチル単結晶処理方法を提供する
ことを課題としている。The present invention has been made in view of such circumstances, and an object of the present invention is to provide a rutile single crystal processing method capable of efficiently obtaining a high quality rutile single crystal having no lattice defect.
【０００５】[0005]
【課題を解決するための手段】本発明は上記の課題を、
ルチル単結晶を、その結晶軸のｃ軸、即ち、（００１）
面を切るようにウエハ状に切断し、その面上にＴｉ
Ｏ2、Ａｌ2Ｏ3、ＳｉＯ2、Ｇａ2Ｏ3、Ｋ2ＣＯ3、Ｎａ2
ＣＯ3、ＺｒＯ2のいずれか一種を薄膜コーティングした
後、所定条件で熱処理することにより、解決した。The present invention solves the above problems by
The rutile single crystal is represented by the c-axis of its crystal axis, that is, (001)
Cut into wafers so that the surface is cut, and Ti
O 2 , Al 2 O 3 , SiO 2 , Ga 2 O 3 , K 2 CO 3 , Na 2
The problem was solved by applying a thin film coating of one of CO 3 and ZrO 2 and then heat treating it under predetermined conditions.
【０００６】また、一旦熱処理して、割れやサブグレイ
ンを生じたルチル単結晶のウエハに対して、その表面に
ＴｉＯ2、Ａｌ2Ｏ3、ＳｉＯ2、Ｇａ2Ｏ3、Ｋ2ＣＯ3、Ｎ
ａ2ＣＯ3、ＺｒＯ2のいずれか一種を薄膜コーティング
した後、所定条件で再び熱処理することによっても、上
記課題を解決することができる。[0006] Further, a rutile single crystal wafer which has once been heat-treated and has cracks and subgrains has TiO 2 , Al 2 O 3 , SiO 2 , Ga 2 O 3 and K 2 CO 3 on its surface. N
The above problem can also be solved by applying a thin film coating of any one of a 2 CO 3 and ZrO 2 and then performing heat treatment again under predetermined conditions.
【０００７】[0007]
【作用】薄膜コーティングした上で熱処理することで、
薄膜成分が作用して、ルチル単結晶の原子配列が理想的
に整理され直され、格子欠陥が除去される。また、熱処
理中に発生する格子欠陥の発生を防止することもでき
る。[Function] By applying a thin film coating and heat treatment,
The thin film components act to ideally rearrange the atomic arrangement of the rutile single crystal and remove lattice defects. It is also possible to prevent the occurrence of lattice defects that occur during heat treatment.
【０００８】薄膜コーティングは、結晶軸のｃ軸に平行
でない、即ち、ｃ軸を切るような面に施す。とりわけ、
ｃ軸に対して４５度以上の角度をもって切るのがよい。
これは、ルチルの原子密度に関し（００１）面が極端に
小さく、そのために原子が拡散し易く、薄膜成分がウエ
ハ表面に効果的に作用すると考えられるからである。The thin film coating is applied to a surface that is not parallel to the c-axis of the crystal axis, that is, cuts the c-axis. Above all,
It is better to cut at an angle of 45 degrees or more with respect to the c-axis.
This is because the (001) plane is extremely small with respect to the atom density of rutile, which makes it easy for atoms to diffuse, and the thin film component is considered to act effectively on the wafer surface.
【０００９】薄膜コーティングに用いる成分は、ＴｉＯ
2、Ａｌ2Ｏ3、ＳｉＯ2、Ｇａ2Ｏ3、Ｋ2ＣＯ3、Ｎａ2Ｃ
Ｏ3、ＺｒＯ2のいずれか一種であるが、特に好ましく
は、Ａｌ2Ｏ3、Ｇａ2Ｏ3、Ｋ2ＣＯ3である。The component used for thin film coating is TiO.
2 , Al 2 O 3 , SiO 2 , Ga 2 O 3 , K 2 CO 3 , Na 2 C
One of O 3 and ZrO 2 , but particularly preferably Al 2 O 3 , Ga 2 O 3 and K 2 CO 3 .
【００１０】薄膜の形成方法は限定されず、例えば、薄
膜原料を水溶媒に懸濁させ、刷毛で塗ったり、ディップ
コーティングする。またゾル-ゲル法やスパッタ法等で
薄膜を形成させるのも有効である。The method for forming the thin film is not limited, and for example, the thin film raw material is suspended in a water solvent and applied with a brush or dip coating. It is also effective to form a thin film by a sol-gel method or a sputtering method.
【００１１】熱処理の際の温度とその保持時間について
は、処理温度を変化させると適切な保持時間も変化す
る。例えば、８００℃の処理温度であれば、３０時間程
度、当該温度を保持する必要があるが、１０００℃にす
れば、１０時間程度の保持で足りる。Regarding the temperature and the holding time during the heat treatment, when the processing temperature is changed, the appropriate holding time also changes. For example, if the treatment temperature is 800 ° C., it is necessary to hold the temperature for about 30 hours, but if the treatment temperature is 1000 ° C., the holding for about 10 hours is sufficient.
【００１２】薄膜コーティングするウエハの面は、コー
ティングの際、薄膜との密着性がよくなる程度に研磨す
るのがよい。The surface of the wafer to be coated with the thin film is preferably polished to such an extent that the adhesion with the thin film is improved during coating.
【００１３】[0013]
【実施例】以下に本発明の実施例をあげてさらに具体的
に説明する。EXAMPLES The present invention will be described in more detail below with reference to examples.
【００１４】実施例１ フローティングゾーン法で育成した直径２５ｍｍ、長さ
１３０ｍｍのルチル単結晶を、結晶軸のｃ軸に垂直に切
断し、厚さ２ｍｍのウエハを複数作製し、それぞれの両
端面を鏡面研磨した。 Example 1 A rutile single crystal having a diameter of 25 mm and a length of 130 mm grown by the floating zone method was cut perpendicularly to the c-axis of the crystal axis to prepare a plurality of wafers having a thickness of 2 mm, and both end faces were formed. It was mirror-polished.
【００１５】一方、純度が９９％以上のＴｉＯ2、Ａｌ2
Ｏ3、ＳｉＯ2、Ｇａ2Ｏ3、Ｋ2ＣＯ3、Ｎａ2ＣＯ3、Ｍｇ
Ｏ、ＣａＣＯ3、Ｆｅ2Ｏ3、ＺｒＯ2のそれぞれの粉末５
ｇを、それぞれ１０ｃｃの純水に混入して、ガラス棒で
撹拌させた後、１０分間超音波洗浄器で分散させて、懸
濁液を調製した。On the other hand, TiO 2 and Al 2 having a purity of 99% or more are used.
O 3 , SiO 2 , Ga 2 O 3 , K 2 CO 3 , Na 2 CO 3 , Mg
Powders of O, CaCO 3 , Fe 2 O 3 and ZrO 2 5
g was mixed with 10 cc of pure water, stirred with a glass rod, and then dispersed with an ultrasonic cleaner for 10 minutes to prepare a suspension.
【００１６】これらの調製液を刷毛でそれぞれウエハの
両面に塗り、室温２０℃、湿度５５％の部屋で自然乾燥
させた。完全に乾燥させてから、これら薄膜コーティン
グ済みウエハと表面をコーティングしていないウエハと
を電気炉に入れ、酸素雰囲気中で１００℃／ｈｒで温度
を上昇させ、１０００℃で１２時間保持した後、１００
℃／ｈｒで常温まで温度を下降させた。Each of these prepared solutions was applied onto both sides of the wafer with a brush and naturally dried in a room at a room temperature of 20 ° C. and a humidity of 55%. After completely drying, the thin film-coated wafer and the surface-uncoated wafer were placed in an electric furnace, the temperature was raised at 100 ° C./hr in an oxygen atmosphere, and the temperature was kept at 1000 ° C. for 12 hours. 100
The temperature was lowered to room temperature at ° C / hr.
【００１７】熱処理後のこれらのウエハの両面を再び鏡
面研磨して、レンズで５ｍｍの直径に集光した白色光を
ウエハの研磨面に対して平行に照射し、白濁並びにサブ
グレイン（小傾角粒界）の程度を観察した。その結果を
表１に示す。After the heat treatment, both surfaces of these wafers are mirror-polished again, and white light condensed by a lens to a diameter of 5 mm is irradiated parallel to the polished surface of the wafer to give white turbidity and subgrains (small-angle grains). The degree of (field) was observed. The results are shown in Table 1.
【００１８】[0018]
【表１】 [Table 1]
【００１９】実施例２ 実施例１と同様に、フローティングゾーン法で育成した
直径２５ｍｍ、長さ１３０ｍｍのルチル単結晶を、結晶
軸のｃ軸に垂直に切断し、厚さ２ｍｍのウエハを複数作
製し、それぞれの両端面を鏡面研磨した。これらのウエ
ハを薄膜コーティングすることなく、実施例１と同じ条
件で熱処理を行い、ウエハに白濁とサブグレインとを生
成させた。 Example 2 In the same manner as in Example 1, a rutile single crystal having a diameter of 25 mm and a length of 130 mm grown by the floating zone method was cut perpendicularly to the c-axis of crystal axes to prepare a plurality of wafers having a thickness of 2 mm. Then, both end faces of each were mirror-polished. These wafers were heat-treated under the same conditions as in Example 1 without being coated with a thin film to generate white turbidity and subgrains on the wafers.
【００２０】一方、純度が９９％以上のＴｉＯ2、Ａｌ2
Ｏ3、ＳｉＯ2、Ｇａ2Ｏ3、Ｋ2ＣＯ3、Ｎａ2ＣＯ3、Ｚｒ
Ｏ2のそれぞれについて、実施例１と同様にして、懸濁
液を調製した。On the other hand, TiO 2 and Al 2 having a purity of 99% or more are used.
O 3 , SiO 2 , Ga 2 O 3 , K 2 CO 3 , Na 2 CO 3 , Zr
A suspension was prepared in the same manner as in Example 1 for each of O 2 .
【００２１】これらの調製液を、実施例１と同様にウエ
ハ両面にコーティングし、室温２０℃、湿度５５％の部
屋で自然乾燥させた後、電気炉に入れ、酸素雰囲気中で
１０００℃で１２時間の間、再熱処理した。熱処理温度
までの加温速度、及び熱処理後の冷却速度は、実施例１
の熱処理工程と同じく、１００℃／ｈｒである。Both surfaces of the wafer were coated with these prepared liquids in the same manner as in Example 1, naturally dried in a room at a room temperature of 20 ° C. and a humidity of 55%, and then placed in an electric furnace at 1000 ° C. in an oxygen atmosphere at 12 ° C. Reheated for a period of time. The heating rate up to the heat treatment temperature and the cooling rate after the heat treatment were the same as those in Example 1.
It is 100 ° C./hr as in the heat treatment step.
【００２２】再熱処理後のこれらのウエハの両面を再び
鏡面研磨して、実施例１と同様にして白濁並びにサブグ
レインの程度を観察したところ、Ａｌ2Ｏ3、Ｇａ2Ｏ3、
Ｋ2ＣＯ3のウエハにおいては、白濁、サブグレインが完
全に消滅していた。またＴｉＯ2、ＳｉＯ2、Ｎａ2Ｃ
Ｏ3、ＺｒＯ2のそれぞれについても、ほとんど白濁、サ
ブグレインが存在していなかった。After the re-heat treatment, both surfaces of these wafers were mirror-polished again, and the degree of cloudiness and subgrains was observed in the same manner as in Example 1. Al 2 O 3 , Ga 2 O 3 ,
In the K 2 CO 3 wafer, white turbidity and subgrains were completely disappeared. In addition, TiO 2 , SiO 2 , Na 2 C
Almost no white turbidity or subgrain was present in each of O 3 and ZrO 2 .
【００２３】実施例３ 実施例１で用いたと同じルチル単結晶を、結晶軸のｃ軸
に対して垂直、４５度及び平行にそれぞれ切断し、それ
ぞれ厚さ２ｍｍのウエハとし、両端面を鏡面研磨した。
それぞれのウエハに対して、純度９９％以上のＴｉ
Ｏ2、Ａｌ2Ｏ3、Ｋ2ＣＯ3から実施例１と同様に調製し
た懸濁液を薄膜コーティングし、実施例１と同じ条件で
乾燥、熱処理、鏡面研磨した。そして実施例１と同様に
して白濁並びにサブグレインの程度を観察した。その結
果を表２に示す。 Example 3 The same rutile single crystal used in Example 1 was cut into a wafer having a thickness of 2 mm, which was cut perpendicularly to the c-axis of the crystal axis at an angle of 45 degrees and parallel to each other, and both end surfaces were mirror-polished. did.
Ti with a purity of 99% or more for each wafer
A suspension prepared from O 2 , Al 2 O 3 and K 2 CO 3 in the same manner as in Example 1 was thin film coated, dried under the same conditions as in Example 1, heat-treated and mirror-polished. Then, in the same manner as in Example 1, the degree of white turbidity and subgrain was observed. The results are shown in Table 2.
【００２４】[0024]
【表２】 [Table 2]
【００２５】この結果から、薄膜コーティングを施すこ
とによる効果は、結晶軸のｃ軸を切る方向でコーティン
グ処理するときに得られることが判明する。ルチルの原
子密度は（００１）面が極端に小さいことが知られてお
り、そのため原子が拡散し易く、薄膜とウエハ表面とで
反応が促進されると考えられる。From these results, it is clear that the effect of applying the thin film coating is obtained when the coating treatment is performed in the direction of cutting the c-axis of the crystal axis. It is known that the atomic density of rutile on the (001) plane is extremely small, and therefore atoms are likely to diffuse, and the reaction between the thin film and the wafer surface is considered to be promoted.
【００２６】実施例４ 熱処理温度及びその保持時間の変化による薄膜コーティ
ング処理の効果の程度を知るために、Ａｌ2Ｏ3につい
て、熱処理温度及びその保持時間を変えて、実験を行っ
た。その結果を表３に示す。なお、熱処理温度及びその
保持時間以外の条件は、実施例１と同じである。 Example 4 In order to know the degree of the effect of the thin film coating treatment by the change of the heat treatment temperature and the holding time thereof, an experiment was conducted for Al 2 O 3 while changing the heat treatment temperature and the holding time thereof. The results are shown in Table 3. The conditions other than the heat treatment temperature and the holding time were the same as in Example 1.
【００２７】[0027]
【表３】 [Table 3]
【００２８】[0028]
【発明の効果】請求項１の処理方法においては、ルチル
単結晶を、その結晶軸のｃ軸を切るようにウエハ状に切
断し、その面上に所定成分を薄膜コーティングした後、
所定条件で熱処理するので、ルチルの原子密度が小さい
方向に対して薄膜成分が効果的に作用して、ルチル単結
晶の原子配列が理想的に整理され、格子欠陥が防止さ
れ、また除去される。According to the processing method of the present invention, the rutile single crystal is cut into a wafer so as to cut the c-axis of its crystal axis, and a predetermined component is thinly coated on the surface thereof,
Since the heat treatment is performed under predetermined conditions, the thin film component effectively acts in the direction in which the rutile atomic density is low, and the atomic arrangement of the rutile single crystal is ideally arranged, and lattice defects are prevented and removed. ..
【００２９】請求項２の処理方法においては、一旦熱処
理して格子欠陥を生じたルチル単結晶のウエハに対し
て、その表面に所定成分を薄膜コーティングした後、所
定条件で再び熱処理するので、薄膜成分が作用して、ル
チル単結晶の原子配列が理想的に整理され直し、格子欠
陥が除去される。In the processing method of the second aspect, a rutile single crystal wafer that has once undergone heat treatment to generate lattice defects is thin-film coated with a predetermined component on the surface thereof, and then heat-treated again under predetermined conditions. The components act to ideally rearrange the atomic arrangement of the rutile single crystal and remove lattice defects.
Claims (2)
るようにウエハ状に切断し、その面上にＴｉＯ2、Ａｌ2
Ｏ3、ＳｉＯ2、Ｇａ2Ｏ3、Ｋ2ＣＯ3、Ｎａ2ＣＯ3、Ｚｒ
Ｏ2のいずれか一種を薄膜コーティングした後、所定条
件で熱処理することを特徴とするルチル単結晶の処理方
法。1. A rutile single crystal is cut into a wafer so as to cut the c-axis of its crystal axis, and TiO 2 , Al 2 is cut on the surface thereof.
O 3 , SiO 2 , Ga 2 O 3 , K 2 CO 3 , Na 2 CO 3 , Zr
A method for treating a rutile single crystal, which comprises applying a thin film coating of any one of O 2 and then performing heat treatment under predetermined conditions.
ｉＯ2、Ａｌ2Ｏ3、ＳｉＯ2、Ｇａ2Ｏ3、Ｋ2ＣＯ3、Ｎａ
2ＣＯ3、ＺｒＯ2のいずれか一種を薄膜コーティングし
た後、所定条件で再熱処理することを特徴とするルチル
単結晶の処理方法。2. The surface of the heat-treated rutile single crystal wafer is provided with T
iO 2 , Al 2 O 3 , SiO 2 , Ga 2 O 3 , K 2 CO 3 , Na
A method for treating a rutile single crystal, which comprises coating a thin film of one of 2 CO 3 and ZrO 2 and then performing heat treatment again under predetermined conditions.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3319051A JP2735422B2 (en) | 1991-12-03 | 1991-12-03 | Rutile single crystal processing method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3319051A JP2735422B2 (en) | 1991-12-03 | 1991-12-03 | Rutile single crystal processing method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH05148091A true JPH05148091A (en) | 1993-06-15 |
| JP2735422B2 JP2735422B2 (en) | 1998-04-02 |
Family
ID=18105961
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3319051A Expired - Fee Related JP2735422B2 (en) | 1991-12-03 | 1991-12-03 | Rutile single crystal processing method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2735422B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| MD4010G2 (en) * | 2007-12-12 | 2010-08-31 | Технический университет Молдовы | Method for obtaining thin films of oxide semiconductors of In2O3 |
| US8747553B2 (en) | 2003-02-24 | 2014-06-10 | Waseda University | β-Ga2O3 single crystal growing method including crystal growth method |
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| JPS63142301A (en) * | 1986-12-04 | 1988-06-14 | Nikon Corp | Optical thin film influenced only slightly by cummulative effect |
| JPH0197902A (en) * | 1987-10-12 | 1989-04-17 | Mitsubishi Electric Corp | Optical device having antireflection film |
| JPH02255531A (en) * | 1989-03-30 | 1990-10-16 | Mazda Motor Corp | Production of lead titanate thin film |
-
1991
- 1991-12-03 JP JP3319051A patent/JP2735422B2/en not_active Expired - Fee Related
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63142301A (en) * | 1986-12-04 | 1988-06-14 | Nikon Corp | Optical thin film influenced only slightly by cummulative effect |
| JPH0197902A (en) * | 1987-10-12 | 1989-04-17 | Mitsubishi Electric Corp | Optical device having antireflection film |
| JPH02255531A (en) * | 1989-03-30 | 1990-10-16 | Mazda Motor Corp | Production of lead titanate thin film |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8747553B2 (en) | 2003-02-24 | 2014-06-10 | Waseda University | β-Ga2O3 single crystal growing method including crystal growth method |
| TWI450865B (en) * | 2003-02-24 | 2014-09-01 | Univ Waseda | Β-ga2o3 type single crystal growth method |
| MD4010G2 (en) * | 2007-12-12 | 2010-08-31 | Технический университет Молдовы | Method for obtaining thin films of oxide semiconductors of In2O3 |
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| JP2735422B2 (en) | 1998-04-02 |
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