JPH09110594A - Heterogeneous epitaxial growth of aluminum oxide single crystal film on silicon substrate and device used for the method - Google Patents
Heterogeneous epitaxial growth of aluminum oxide single crystal film on silicon substrate and device used for the methodInfo
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- JPH09110594A JPH09110594A JP29328595A JP29328595A JPH09110594A JP H09110594 A JPH09110594 A JP H09110594A JP 29328595 A JP29328595 A JP 29328595A JP 29328595 A JP29328595 A JP 29328595A JP H09110594 A JPH09110594 A JP H09110594A
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- substrate
- single crystal
- crystal film
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- Crystals, And After-Treatments Of Crystals (AREA)
- Physical Deposition Of Substances That Are Components Of Semiconductor Devices (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】この発明は、半導体製造工業
に於いて、ＬＳＩ等の基板として使用されるＳＯＩ（Ｓ
ｉ ｏｎ Ｉｎｓｕｌａｔｏｒ）基板の絶縁膜となるＡ
ｌ2Ｏ3単結晶膜のヘテロエピタキシャル成長方法及び該
方法に使用する装置に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an SOI (S) used as a substrate for LSI or the like in the semiconductor manufacturing industry.
Ion Insulator) A as the insulating film of the substrate
The present invention relates to a heteroepitaxial growth method for an l 2 O 3 single crystal film and an apparatus used for the method.
【０００２】[0002]
【従来の技術】従来、Ｓｉ基板上にＡｌ2Ｏ3単結晶膜を
ヘテロエピタキシャル成長させるには、材料アルミニウ
ム（Ａｌ）源として、トリメチルアルミニウムガス（Ｔ
ＭＡ：Ａｌ（ＣＨ3）3）、酸素（Ｏ）源としてＮ2Ｏガ
スを使用し、ガスソ−ス分子線エピタキシャルまたは減
圧気相成長法により行っていた。2. Description of the Related Art Conventionally, in order to heteroepitaxially grow an Al 2 O 3 single crystal film on a Si substrate, trimethylaluminum gas (T) is used as a material aluminum (Al) source.
MA: Al (CH 3) 3 ), using oxygen (O) source as the N 2 O gas, Gasuso - has been performed by the scan molecular beam epitaxy or vacuum vapor deposition.
【０００３】[0003]
【発明が解決しようとする課題】前述した従来の方法で
は、Ａｌ源に有機金属ガスのＴＭＡを使用しているた
め、Ｓｉ基板とＡｌ2Ｏ3単結晶膜との界面において、Ｔ
ＭＡの分解による副産物として生成した炭素の混入が避
けられなかった。この界面への炭素混入は、従来法で
は、成長方法の改良などで多少減少させることは可能で
あったが、分析装置の検出限界以下までの減少は極めて
困難であった。In the above-mentioned conventional method, since TMA which is an organometallic gas is used as the Al source, T at the interface between the Si substrate and the Al 2 O 3 single crystal film is used.
Incorporation of carbon generated as a by-product due to the decomposition of MA was unavoidable. In the conventional method, it was possible to reduce the amount of carbon mixed into the interface to some extent by improving the growth method, but it was extremely difficult to reduce the amount of carbon to below the detection limit of the analyzer.
【０００４】Ｓｉ基板とＡｌ2Ｏ3単結晶膜との界面に混
入した炭素は、成長させたＡｌ2Ｏ3単結晶膜の結晶性、
表面平坦性等を劣化させるので、ＳＯＩ基板として用い
てその上に素子を作成したとき、所望の特性が得られな
い等の欠点を招来する。この発明は、このような点に着
目してなされたものであり、界面への炭素混入量を極端
に低減させ、Ｓｉ基板上のＡｌ2Ｏ3単結晶膜の結晶性、
表面平滑性等の種々の特性劣化を改善したＳｉ基板上へ
のＡｌ2Ｏ3単結晶膜のヘテロエピタキシャル成長方法及
び該方法に使用する装置を提供することを目的とする。The carbon mixed in the interface between the Si substrate and the Al 2 O 3 single crystal film causes the crystallinity of the grown Al 2 O 3 single crystal film,
Since the surface flatness and the like are deteriorated, when an element is formed on the SOI substrate by using it as an SOI substrate, there arises a defect that desired characteristics cannot be obtained. The present invention has been made paying attention to such a point, the amount of carbon mixed into the interface is extremely reduced, and the crystallinity of the Al 2 O 3 single crystal film on the Si substrate,
An object of the present invention is to provide a method for heteroepitaxial growth of an Al 2 O 3 single crystal film on a Si substrate in which deterioration of various characteristics such as surface smoothness is improved, and an apparatus used for the method.
【０００５】[0005]
【課題を解決するための手段】上記目的を達成するた
め、本発明者は、鋭意研究の結果、従来の方法でＡｌ源
として用いたＴＭＡの代わりに、固体Ａｌを使用するこ
とによって、Ｓｉ基板とＡｌ2Ｏ3単結晶膜との界面への
炭素混入が低減し、その結果、Ｓｉ基板上のＡｌ2Ｏ3単
結晶膜の結晶性、表面平滑性等の種々の特性劣化が著し
く改善することを見いだし、本発明に到達した。In order to achieve the above object, the inventors of the present invention have earnestly studied, and as a result, by using solid Al instead of TMA used as an Al source in the conventional method, a Si substrate was obtained. Of carbon at the interface between the Al 2 O 3 single crystal film and Al 2 O 3 is reduced, and as a result, deterioration of various characteristics such as crystallinity and surface smoothness of the Al 2 O 3 single crystal film on the Si substrate is remarkably improved. Then, the present invention was reached.
【０００６】即ち、本発明の成長方法は、真空装置内に
Ｓｉ基板を配置し、該Ｓｉ基板上へアルミニウム分子線
とＮ2Ｏガスとを照射することを特徴とする。また、本
発明の成長装置は、真空装置内に配置したＳｉ基板と、
該真空装置に取着したＮ2Ｏガス導入管及び固体アルミ
ニウムを内装したクヌ−センセルと、アルミニウム分子
線を発生させるため該クヌ−センセルを加熱する手段と
を具備してなることを特徴とする。That is, the growth method of the present invention is characterized in that a Si substrate is placed in a vacuum apparatus, and the Si molecular substrate is irradiated with an aluminum molecular beam and N 2 O gas. The growth apparatus of the present invention includes a Si substrate arranged in a vacuum apparatus,
The vacuum device is equipped with a N 2 O gas introduction pipe and a Knu-Sensel containing solid aluminum, and means for heating the Knu-Sensel to generate an aluminum molecular beam. .
【０００７】[0007]
【発明の実施の形態】次に、本発明の実施例を図面に基
づいて説明する。図１は、本発明の成長装置の該略図で
あり、円筒形の内部を真空にする真空装置５と、該真空
装置５内の中央に配置したＳｉ基板３と、該真空装置５
に取着したＮ2Ｏガス導入管１と、内部に固体アルミニ
ウムを内装したステンレス製クヌ−センセル２とから構
成した例を示す。尚、図中６は、タ−ボ分子ポンプであ
り、７はロ−タリ−ポンプであり、真空装置５内を高度
の真空状態にするため、このように両ポンプを併用して
いる。Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic view of a growth apparatus of the present invention, which is a vacuum apparatus 5 for evacuating a cylindrical shape, a Si substrate 3 arranged in the center of the vacuum apparatus 5, and the vacuum apparatus 5.
An example constituted by a N 2 O gas introduction pipe 1 attached to the above and a stainless steel Knu-Sensel 2 having solid aluminum inside is shown. In the figure, 6 is a turbo molecular pump, 7 is a rotary pump, and both pumps are used together in this way in order to bring the inside of the vacuum device 5 to a high vacuum state.
【０００８】Ｎ2Ｏガス導入管１及びクヌ−センセル２
は、Ｓｉ基板３に、それぞれＮ2Ｏガス及びアルミニウ
ム分子線を照射し得るように、照射口がＳｉ基板３に対
向配置されている。クヌ−センセル２の照射口には、シ
ャッタ−４が開閉自在に取着され、アルミニウム分子線
を照射するときは、シャッタ−４を閉じるようになって
いる。クヌ−センセル２内には、ヒ−タ−（図示せず）
が内装され、該ヒ−タ−によって、固体アルミニウムを
１１００℃前後に加熱し、アルミニウムを溶解、蒸発さ
せ、アルミニウム分子線を生成させるようになってい
る。N 2 O gas introduction tube 1 and Knu-Sensel 2
In order to irradiate the Si substrate 3 with the N 2 O gas and the aluminum molecular beam, the irradiation port is arranged to face the Si substrate 3. A shutter 4 is attached to the irradiation opening of the Knu-Sensel 2 so as to be openable and closable, and the shutter 4 is closed when the aluminum molecular beam is irradiated. A heater (not shown) is provided in the Knu-Sensel 2.
, The solid aluminum is heated by the heater to around 1100 ° C. to dissolve and evaporate the aluminum to generate an aluminum molecular beam.
【０００９】次に、上記本発明の装置を使用して、Ｓｉ
基板上へＡｌ2Ｏ3単結晶膜をヘテロエピタキシャル成長
させる方法を、図１に基づいて説明する。まず最初に、
Ｓｉ基板３を化学洗浄した後、真空装置（成長室）５内
に配置する。ついで、タ−ボ分子ポンプ６とロ−タリ−
ポンプ７とによって、真空装置５内を１×１０-7Ｐａの
真空度とし、空気等に含まれている不純物を除去する。
それから、真空装置５内の真空度を３×１０-2Ｐａに落
とし、温度を８５０℃とし、クヌ−センセル２のヒ−タ
−で固体アルミニウムを１１００℃に加熱して、アルミ
ニウムを溶解、蒸発させ、Ａｌ分子線を生成させる。Next, using the above apparatus of the present invention, Si
A method of heteroepitaxially growing an Al 2 O 3 single crystal film on a substrate will be described with reference to FIG. First of all,
After the Si substrate 3 is chemically cleaned, it is placed in a vacuum device (growth chamber) 5. Next, the turbo molecular pump 6 and rotary
With the pump 7, the inside of the vacuum device 5 is set to a vacuum degree of 1 × 10 −7 Pa to remove impurities contained in air and the like.
Then, the degree of vacuum in the vacuum device 5 is reduced to 3 × 10 -2 Pa, the temperature is set to 850 ° C., and the solid aluminum is heated to 1100 ° C. by the heater of the Knu-Sensel 2 to dissolve and evaporate the aluminum. Then, an Al molecular beam is generated.
【００１０】Ｓｉ基板上へのＡｌ分子線の照射は、クヌ
−センセル２の照射口に取着したシャッタ−４の開閉に
よって制御される。シャッタ−４を開けて、Ｓｉ基板上
へＡｌ分子線を照射し、同時にＮ2ＯガスをＮ2Ｏガス導
入管１からＳｉ基板上へ照射する。このように８５０℃
で３０分間処理して、Ｓｉ基板上へＡｌ2Ｏ3単結晶膜を
ヘテロエピタキシャル成長させる。The irradiation of the Al molecular beam on the Si substrate is controlled by opening and closing the shutter-4 attached to the irradiation port of the Knu-Sensel cell 2. The shutter-4 is opened, and the Al molecular beam is irradiated onto the Si substrate, and at the same time, the N 2 O gas is irradiated from the N 2 O gas introduction pipe 1 onto the Si substrate. 850 ℃ like this
For 30 minutes to heteroepitaxially grow an Al 2 O 3 single crystal film on a Si substrate.
【００１１】上記のようにして成長させたＡｌ2Ｏ3単結
晶膜を、Ｘ線光電子分光法によって組成分析した。結果
のチャ−トを図２に示す。図２より明らかなように、Ａ
ｌと酸素（Ｏ）との化学量論比は、サフアイアと一致
し、炭素は検出限界以下であった。The composition of the Al 2 O 3 single crystal film grown as described above was analyzed by X-ray photoelectron spectroscopy. The resulting chart is shown in FIG. As is clear from FIG.
The stoichiometric ratio of 1 to oxygen (O) was consistent with sapphire and carbon was below the detection limit.
【００１２】また、反射高速電子線回折によって、成長
膜の結晶性を観測した。結果の反射高速電子線回折像を
図３に示す。図３より明らかなように、回折像はストリ
−クパタ−ンとなった。このことは、Ａｌ2Ｏ3単結晶膜
の結晶性及び表面平坦性が、従来の方法によって成長さ
せたＡｌ2Ｏ3単結晶膜よりも、はるかに良質であること
を示すものである。Further, the crystallinity of the grown film was observed by reflection high-energy electron diffraction. The resulting reflection high-energy electron diffraction image is shown in FIG. As is clear from FIG. 3, the diffraction pattern became a strike pattern. This crystallinity and surface flatness Al 2 O 3 single crystal film, than Al 2 O 3 single crystal film grown by a conventional method, showing that it is a much more good.
【００１３】[0013]
【発明の効果】以上述べた如く、本発明によれば、Ｓｉ
基板とＡｌ2Ｏ3単結晶膜との界面に混入する炭素量をな
くすか、若しくは著しく低減させることができるので、
従来法と比べて、Ａｌ2Ｏ3単結晶膜の結晶性及び平坦性
が格段に改善されると共に、このことによって、ＳＯＩ
基板としての素子を作成する際に、素子の特性劣化を防
ぎ、高性能な素子の作成が可能となる等の画期的な効果
が得られる。As described above, according to the present invention, Si
Since the amount of carbon mixed in the interface between the substrate and the Al 2 O 3 single crystal film can be eliminated or significantly reduced,
Compared with the conventional method, the crystallinity and flatness of the Al 2 O 3 single crystal film are remarkably improved.
In producing an element as a substrate, epoch-making effects such as prevention of characteristic deterioration of the element and production of a high-performance element can be obtained.
【００１４】[0014]
【図１】本発明の成長装置の概略図である。FIG. 1 is a schematic view of a growth apparatus of the present invention.
【図２】本発明の方法により得たＡｌ2Ｏ3単結晶膜のＸ
線光電子分光法による組成分析チャ−トである。FIG. 2 is an X of an Al 2 O 3 single crystal film obtained by the method of the present invention.
It is a composition analysis chart by a line photoelectron spectroscopy.
【図３】本発明の方法により得たＡｌ2Ｏ3単結晶膜の反
射高速電子線回折像である。FIG. 3 is a reflection high-energy electron diffraction image of an Al 2 O 3 single crystal film obtained by the method of the present invention.
１ Ｎ2Ｏガス導入管 ２ クヌ−センセル ３ Ｓｉ基板 ４ クヌ−センセルの照射口に設けた
シャッタ− ５ 真空装置1 N 2 O gas introduction tube 2 Knu-Sensel 3 Si substrate 4 Shutter provided at irradiation port of Knu-Sensel 5 Vacuum device
─────────────────────────────────────────────────────
────────────────────────────────────────────────── ───
【手続補正書】[Procedure amendment]
【提出日】平成８年３月２２日[Submission date] March 22, 1996
【手続補正１】[Procedure amendment 1]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】図面の簡単な説明[Correction target item name] Brief description of drawings
【補正方法】変更[Correction method] Change
【補正内容】[Correction contents]
【図面の簡単な説明】[Brief description of the drawings]
【図１】本発明の成長装置の概略図である。FIG. 1 is a schematic view of a growth apparatus of the present invention.
【図２】本発明の方法により得たＡｌ２Ｏ３単結晶膜の
Ｘ線光電子分光法による組成分析チヤ−トである。FIG. 2 is a composition analysis chart of an Al 2 O 3 single crystal film obtained by the method of the present invention by X-ray photoelectron spectroscopy.
【図３】本発明の方法により得たＡｌ２Ｏ３単結晶膜の
結晶構造を示す反射高速電子線回折像である。FIG. 3 is a reflection high-energy electron diffraction image showing the crystal structure of an Al 2 O 3 single crystal film obtained by the method of the present invention.
Claims (4)
板上へアルミニウム分子線とＮ2Ｏガスとを照射するこ
とを特徴とするＳｉ基板上へのＡｌ2Ｏ3単結晶膜のヘテ
ロエピタキシャル成長方法。1. An Al 2 O 3 single crystal film on a Si substrate, characterized in that a Si substrate is placed in a vacuum apparatus, and the Si substrate is irradiated with an aluminum molecular beam and N 2 O gas. Heteroepitaxial growth method.
ウムを前記真空装置内で加熱蒸発させて生成させたもの
である請求項１に記載のヘテロエピタキシャル成長方
法。2. The heteroepitaxial growth method according to claim 1, wherein the aluminum molecular beam is generated by heating and evaporating solid aluminum in the vacuum apparatus.
装置に取着したＮ2Ｏガス導入管及び固体アルミニウム
を内装したクヌ−センセルと、アルミニウム分子線を発
生させるため該クヌ−センセルを加熱する手段とを具備
してなることを特徴とするＳｉ基板上へのＡｌ2Ｏ3単結
晶膜のヘテロエピタキシャル成長装置。3. A Si substrate placed in a vacuum apparatus, a Knu-Sens cell fitted with the vacuum apparatus and containing a N 2 O gas introducing tube and solid aluminum, and the Knu-Sens cell for generating an aluminum molecular beam. A device for heteroepitaxial growth of an Al 2 O 3 single crystal film on a Si substrate, characterized by comprising:
なシャッタ−を取着し、該シャッタ−を開口させること
によって、前記アルミニウム分子線を前記Ｓｉ基板に照
射するように構成してなる請求項３に記載のヘテロエピ
タキシャル成長装置。4. A structure in which an openable and closable shutter is attached to the irradiation opening of the Knu-Sens cell and the aluminum molecular beam is irradiated to the Si substrate by opening the shutter. The heteroepitaxial growth apparatus according to claim 3.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP29328595A JP3841111B2 (en) | 1995-10-17 | 1995-10-17 | Heteroepitaxial growth of Al2O3 single crystal film on Si substrate, and apparatus used in the method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP29328595A JP3841111B2 (en) | 1995-10-17 | 1995-10-17 | Heteroepitaxial growth of Al2O3 single crystal film on Si substrate, and apparatus used in the method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH09110594A true JPH09110594A (en) | 1997-04-28 |
| JP3841111B2 JP3841111B2 (en) | 2006-11-01 |
Family
ID=17792860
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP29328595A Expired - Lifetime JP3841111B2 (en) | 1995-10-17 | 1995-10-17 | Heteroepitaxial growth of Al2O3 single crystal film on Si substrate, and apparatus used in the method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3841111B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2007029754A1 (en) * | 2005-09-06 | 2007-03-15 | National Institute For Materials Science | Alumina film substrate and its fabrication method |
-
1995
- 1995-10-17 JP JP29328595A patent/JP3841111B2/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2007029754A1 (en) * | 2005-09-06 | 2007-03-15 | National Institute For Materials Science | Alumina film substrate and its fabrication method |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3841111B2 (en) | 2006-11-01 |
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