JP2983084B2 - Thin film forming method and vacuum film forming apparatus using this method - Google Patents
Thin film forming method and vacuum film forming apparatus using this methodInfo
- Publication number
- JP2983084B2 JP2983084B2 JP3212696A JP21269691A JP2983084B2 JP 2983084 B2 JP2983084 B2 JP 2983084B2 JP 3212696 A JP3212696 A JP 3212696A JP 21269691 A JP21269691 A JP 21269691A JP 2983084 B2 JP2983084 B2 JP 2983084B2
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- JP
- Japan
- Prior art keywords
- vacuum
- substrate
- thin film
- holding means
- film forming
- Prior art date
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Description
【０００１】[0001]
【産業上の利用分野】本発明は、薄膜形成方法および、
この方法を用い、基板上に半導体フィルムのエピタキシ
ャル成長等を行わせるために真空槽内に基板加熱装置を
備えた真空成膜装置に関する。The present invention relates to a method for forming a thin film, and
The present invention relates to a vacuum film forming apparatus including a substrate heating device in a vacuum chamber for performing epitaxial growth of a semiconductor film on a substrate by using this method.
【０００２】[0002]
【従来の技術】このような真空成膜装置について多くの
提案がなされている。例えば下記の文献はいずれも基板
加熱が必要なＣＶＤについて記述されている。アーサ
Ｐ．ヘイル等のＣＶＤに関する米国特許３，１５６，５
９１号記載の「ＣＶＤにおける２酸化シリコンのマスク
を用いたエピタキシャル成長」Ｔ．オーミ等のアプライ
ドフィジックス・レター５２（１４）１９８８年４月４
日発行の「低温における自由ジェット分子流を用いた高
速成長・表面反応フイルム形成技術」キヨシ，フジナガ
等のジャーナル，オブ，バキューム，ソサイアテイ，テ
クノールＢ５（６）１９８７年１１／１２月発行記載の
「低圧ＣＶＤにおけるＳｉＨ4 を用いてゲルマニュームの上のシリコンのエピタキシ
−」 特開平１−２５７３２２号，発明の名称 半導体の製造
方法 特開平１−２３０２２５号，発明の名称 半導体製造装
置 特開平１−２３０２２６号，発明の名称 半導体製造装
置2. Description of the Related Art Many proposals have been made for such a vacuum film forming apparatus. For example, the following documents all describe CVD requiring substrate heating. Artha P. US Patent 3,156,5 for CVD of Hale et al.
No. 91, "Epitaxial growth using a mask of silicon dioxide in CVD". Applied Physics Letter 52 (14) by Ohmi et al. April 4, 1988
"High-speed growth and surface-reaction film forming technology using free jet molecular flow at low temperature", published by Kiyoshi, Fujinaga, and other journals, Ob, Vacuum, Society, Technol B5 (6) November / December 1987. Epitaxy of silicon on germanium using SiH 4 in low-pressure CVD ”JP-A-1-257322, title of the invention Semiconductor manufacturing method JP-A-1-230225, title of the invention Semiconductor manufacturing apparatus JP-A-1-230226 Title of the Invention Semiconductor Manufacturing Equipment
【０００３】これらの基板加熱を必要とする従来のガス
ソースエピタキシー装置において、基板を加熱するため
の熱源を真空槽内に置く構造のものは基板とともに熱源
もソースガスに曝されるようになっている。そのため上
記従来装置では、ガスを処理槽内に導入して基板加熱を
行うと、熱源および熱源周囲でガスが分解して処理の対
象である基板以外に付着物が発生することとなる。基板
加熱装置に付着物が発生した場合には、基板加熱装置の
絶縁性が劣化し、熱源であるヒータに通電できなくなっ
たり、熱源の熱輻射に強度変化が生じたり、さらには熱
輻射の均一性が悪化するという問題が生じていた。ま
た、基板加熱装置その他に付着した付着物が塵の原因に
なり、薄膜形成の歩留りを低下させていた。この他に、
ヒータを加熱した際にヒータからの炭素等の不純物が基
板に飛来するという問題もあった。In such a conventional gas source epitaxy apparatus requiring substrate heating, a structure in which a heat source for heating a substrate is placed in a vacuum chamber is such that the heat source is exposed to the source gas together with the substrate. I have. Therefore, in the above-described conventional apparatus, when the substrate is heated by introducing the gas into the processing tank, the gas is decomposed around the heat source and the heat source, and deposits are generated other than the substrate to be processed. If deposits occur on the substrate heating device, the insulation of the substrate heating device will deteriorate, and it will be impossible to energize the heater that is the heat source, the heat radiation of the heat source will change in intensity, and the heat radiation will be even. However, there has been a problem that the properties are deteriorated. In addition, the deposits attached to the substrate heating device and the like cause dust and reduce the yield of thin film formation. In addition,
Another problem is that impurities such as carbon from the heater fly to the substrate when the heater is heated.
【０００４】[0004]
【発明が解決しようとする課題】本発明の目的は、真空
排気手段により排気される真空容器の基板保持手段に基
板を設置し、この基板を基板加熱手段により加熱しつつ
真空容器内に原料ガスを供給して薄膜を堆積する薄膜形
成方法において、ソースガスに原因する生成物が基板保
持手段に付着し剥離することによる塵の発生を防止でき
る薄膜形成方法を提供することにある。本発明の他の目
的は、熱源および熱源周囲へのソースガスによる生成物
の付着を防ぎ、基板表面には熱源からのソースガス以外
のガスが飛来することを防止し、ソースガスに原因する
生成物が基板保持手段に付着し剥離することによる塵の
発生を防止できる真空成膜装置を提供することにある。SUMMARY OF THE INVENTION An object of the present invention is to place a substrate on a substrate holding means of a vacuum vessel evacuated by vacuum evacuation means, and to heat the substrate by a substrate heating means and to place a raw material gas in the vacuum vessel. The object of the present invention is to provide a method for forming a thin film in which a product caused by a source gas adheres to a substrate holding means and peels off, thereby preventing generation of dust. Another object of the present invention is to prevent the deposition of products due to a heat source and a source gas around the heat source, to prevent a gas other than the source gas from the heat source from flying to the substrate surface, and to prevent generation of a gas caused by the source gas. An object of the present invention is to provide a vacuum film forming apparatus capable of preventing generation of dust due to an object adhering to a substrate holding means and peeling off.
【０００５】[0005]
【課題を解決するための手段】前記目的を達成するため
に本発明による薄膜形成方法は、真空排気手段により排
気される真空容器の基板保持手段に基板を設置し、当該
基板を基板加熱手段により加熱しつつ前記真空容器内に
原料ガスを供給して薄膜を堆積する薄膜形成方法におい
て、堆積する薄膜と同じ物質で構成された基板保持手段
を用いて薄膜の堆積を行うように構成されている。In order to achieve the above object, a thin film forming method according to the present invention comprises the steps of: mounting a substrate on a substrate holding means of a vacuum vessel evacuated by an evacuating means; In the thin film forming method of depositing a thin film by supplying a raw material gas into the vacuum vessel while heating, the thin film is deposited using a substrate holding means made of the same material as the thin film to be deposited. .
【０００６】前記他の目的を達成するために本発明によ
る真空成膜装置は、真空排気手段により排気される真空
容器中に、基板保持手段と、当該基板保持手段に保持さ
れた基板を加熱する基板加熱手段とを有し、前記基板保
持手段を形成する材料は、前記基板上に堆積する薄膜と
同じ物質で構成されている。また、本発明は、第１およ
び第２の真空槽空間を有する真空容器と、前記第１の真
空槽と前記第２の真空槽それぞれに連通する第１および
第２の真空排気手段と、前記第１の真空槽に設けられた
基板加熱手段と、前記第２の真空槽に設けられたガス供
給手段と、基板の薄膜形成面を第２の真空槽に向けて保
持し、前記基板とともに前記第１および第２の真空槽を
分離する位置に配置される基板保持手段とから構成さ
れ、前記基板保持手段を形成する材料は、その基板上に
堆積する薄膜と同じ物質で構成されている。前記基板保
持手段は前記基板を密着保持し，上下方向に移動可能で
あり、前記真空容器の内壁に設けられた前記第１および
第２の真空槽を分離する仕切り位置に設けられた仕切り
用の部材に密着させられる部材とすることができる。前
記基板保持手段を移動し基板を交換するために前記真空
容器の大気側で操作可能に設けられた運動導入手段を設
置することができる。前記基板加熱手段は電気ヒータで
構成することができる。前記ガス供給手段は前記基板に
向けてガスを放出するノズルとすることができる。前記
第１の真空槽と前記第２の真空槽のそれぞれに設置され
た各真空排気手段は、ターボ分子ポンプとすることがで
きる。前記第１の真空槽に設置された真空排気手段の排
気能力は、前記第２の真空槽に配置された前記真空槽排
気手段の排気能力より小さいものとすることができる。
前記基板上に堆積する薄膜は、エピタキシャルＳｉ薄膜
とすることができる。このような構成によれば、基板処
理面側に向けて導入されたガスは基板裏面側に配置され
た基板加熱装置には至らない。したがって、基板加熱装
置そのものには生成物は発生しない。また、熱源加熱の
際発生する炭素等の不純物も基板の処理面側に飛来する
ことはない。そして基板保持手段等は基板同様加熱され
るため生成物の付着が起こるが、基板保持手段等を成膜
材料と同じものを用いていることにより、付着物と基板
保持手段間の熱応力の違いによる付着物の剥離が起こり
難く、この剥離に原因する塵の発生を防止することがで
きる。In order to achieve the above object, a vacuum film forming apparatus according to the present invention heats a substrate holding means and a substrate held by the substrate holding means in a vacuum vessel evacuated by vacuum evacuation means. A substrate heating means, and a material forming the substrate holding means is made of the same substance as a thin film deposited on the substrate. The present invention also provides a vacuum vessel having first and second vacuum vessel spaces, first and second vacuum exhaust means communicating with the first vacuum vessel and the second vacuum vessel, respectively, The substrate heating means provided in the first vacuum chamber, the gas supply means provided in the second vacuum chamber, and the thin film forming surface of the substrate is held toward the second vacuum chamber, and the substrate is held together with the substrate. And a substrate holding means disposed at a position separating the first and second vacuum chambers, and a material forming the substrate holding means is made of the same substance as a thin film deposited on the substrate. The substrate holding means holds the substrate in close contact, is vertically movable, and has a partitioning position provided at a partitioning position separating the first and second vacuum tanks provided on the inner wall of the vacuum vessel. It can be a member that is brought into close contact with the member. A movement introducing means operably provided on the atmosphere side of the vacuum vessel may be provided for moving the substrate holding means and exchanging the substrate. The substrate heating means can be constituted by an electric heater. The gas supply means may be a nozzle for discharging gas toward the substrate. Each of the vacuum evacuation means provided in each of the first vacuum chamber and the second vacuum chamber may be a turbo-molecular pump. The evacuation capacity of the evacuation means provided in the first vacuum chamber may be smaller than the evacuation capacity of the evacuation means provided in the second vacuum chamber.
The thin film deposited on the substrate may be an epitaxial Si thin film. According to such a configuration, the gas introduced toward the substrate processing surface does not reach the substrate heating device arranged on the substrate rear surface. Therefore, no product is generated in the substrate heating device itself. Further, impurities such as carbon generated at the time of heat source heating do not fly to the processing surface side of the substrate. The substrate holding means and the like are heated similarly to the substrate, so that the product adheres.However, since the same material is used for the substrate holding means and the like as the film forming material, the difference in thermal stress between the attached matter and the substrate holding means is caused. This makes it difficult for the adhered material to peel off, thereby preventing the generation of dust due to the peeling.
【０００７】[0007]
【実施例】以下、図面等を参照して本発明をさらに詳し
く説明する。だだし、これらの図面は、この発明が理解
できる程度に各構成部分の大きさ，形状および配置関係
を概略的に示してあるにすぎない。図１は本発明による
薄膜形成方法および真空成膜装置の実施例を説明するた
めの図で、真空成膜装置を一部断面で示した正面図であ
る。この実施例はＳｉ2 Ｈ6（ジシラン）を用いて基板
上にシリコン膜を成長させる真空成膜装置について示さ
れている。本装置の真空容器６は上部のヒータ側真空槽
（第１の真空槽）６ａと下部の処理側真空槽（第２の真
空槽）６ｂの空間を備えている。真空容器６の内周に
は、容器内を真空槽６ａと６ｂの空間に分割する位置を
決める仕切り用のリム６ｃが設けられている。これら真
空槽６ａ，６ｂ間は被熱処理基板であるシリコン基板２
およびシリコン基板２を搭載する基板保持手段１により
前記リム６ｃの位置で仕切られるようになっている。真
空槽６ａおよび６ｂには排気のためのターボ分子ポンプ
７および９がそれぞれ独立に各真空槽６ａおよび６ｂの
空気を排気することができる。この実施例ではターボ分
子ポンプ７の排気能力は３００リットル／ｓｅｃおよび
ターボ分子ポンプ９の排気能力は１０００リットル／ｓ
ｅｃである。真空槽６ａの中央部には筒状のホルダ１１
で基板加熱用ヒータ３を含む基板加熱装置が支持されて
いる。ヒータ３は外部に配置された直流電源１０より給
電されて加熱されるようになっている。なお、ランプヒ
ータを真空容器６の外部に設置して、真空容器６に取り
付けられた石英製のビューイングポートを介して、基板
２を輻射熱で加熱してもよい。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in more detail with reference to the drawings. However, these drawings only schematically show the size, shape and arrangement of each component so that the present invention can be understood. FIG. 1 is a view for explaining an embodiment of a thin film forming method and a vacuum film forming apparatus according to the present invention, and is a front view showing a partial cross section of the vacuum film forming apparatus. This embodiment shows a vacuum film forming apparatus for growing a silicon film on a substrate using Si 2 H 6 (disilane). The vacuum vessel 6 of the present apparatus has a space for an upper heater-side vacuum tank (first vacuum tank) 6a and a lower processing-side vacuum tank (second vacuum tank) 6b. On the inner periphery of the vacuum container 6, a partitioning rim 6c for determining a position at which the inside of the container is divided into vacuum chambers 6a and 6b is provided. Between these vacuum chambers 6a and 6b, a silicon substrate 2 which is a substrate to be heat-treated is provided.
And a substrate holding means 1 on which a silicon substrate 2 is mounted. Turbo molecular pumps 7 and 9 for exhausting the vacuum chambers 6a and 6b can independently exhaust the air from the vacuum chambers 6a and 6b, respectively. In this embodiment, the exhaust capacity of the turbo-molecular pump 7 is 300 l / sec, and the exhaust capacity of the turbo-molecular pump 9 is 1000 l / s.
ec. A cylindrical holder 11 is provided at the center of the vacuum chamber 6a.
Supports a substrate heating apparatus including the substrate heating heater 3. The heater 3 is heated by being supplied with power from a DC power supply 10 arranged outside. Note that a lamp heater may be provided outside the vacuum vessel 6 and the substrate 2 may be heated by radiant heat via a quartz viewing port attached to the vacuum vessel 6.
【０００８】図６に基板加熱装置の外観を示してある。
筒１１と一体の容器１２の下端に石英製の皿状の受け皿
１３が着脱可能に設けられ前述したヒータ３は前述した
受け皿の底面に配置され石英を介して熱線を基板２に向
けて放射する。一方、真空槽６ｂには側部よりガスノズ
ル８が導入されており、ガスノズル８の先端は真空槽６
ｂの中央部より基板に向けて配置されている。FIG. 6 shows the appearance of the substrate heating apparatus.
A dish-shaped tray 13 made of quartz is detachably provided at a lower end of a container 12 integrated with the cylinder 11, and the heater 3 is disposed on the bottom of the tray and emits heat rays toward the substrate 2 via quartz. . On the other hand, a gas nozzle 8 is introduced into the vacuum chamber 6b from the side.
It is arranged toward the substrate from the center of b.
【０００９】Ｓｉ基板２を保持するための基板保持手段
１は輪形状をしており、内周側および外周側にそれぞれ
段差部１ａ，１ｂを有し、段差部１ａ部分でＳｉ基板２
を受けるように構成されている。基板保持手段１は複数
本の支柱４の先端部に固定され、支柱４の他方端は図示
しない部材で真空槽６ａに固定されたガイド板２２のガ
イド孔２２ａを貫通するようにガイド孔２２ａに案内さ
れる。支柱４の内、１本は真空槽６ａの上壁を貫通して
延長され、真空容器６の外部に設けた直線導入機５に結
合されている。直線導入機５を動作させ前記支柱４を昇
降させることにより、前記支柱の下端に設けられている
基板保持手段１を昇降させることができる。図１は、図
示の位置よりも下方でＳｉ基板２を搭載した基板保持手
段１を直線導入機５を動作させて上昇させ、基板保持手
段１の段差部１ｂと前記仕切り用のリム６ｃの内周下端
とを密着係合させて真空槽６ａ，６ｂを仕切った状態を
示している。The substrate holding means 1 for holding the Si substrate 2 has a ring shape, and has step portions 1a and 1b on the inner peripheral side and the outer peripheral side, respectively.
It is configured to receive. The substrate holding means 1 is fixed to the tip of a plurality of columns 4, and the other end of the column 4 is inserted into a guide hole 22 a through a guide hole 22 a of a guide plate 22 fixed to a vacuum chamber 6 a by a member (not shown). You will be guided. One of the columns 4 extends through the upper wall of the vacuum chamber 6 a and is connected to a linear introduction device 5 provided outside the vacuum vessel 6. By operating the linear introduction device 5 to move the support 4 up and down, the substrate holding means 1 provided at the lower end of the support can be moved up and down. FIG. 1 shows a state in which the substrate holding means 1 on which the Si substrate 2 is mounted is raised below the position shown in the drawing by operating the linear introduction device 5, and the stepped portion 1b of the substrate holding means 1 and the rim 6c for partitioning the substrate. A state is shown in which the vacuum chambers 6a and 6b are partitioned by closely engaging the lower peripheral edge.
【００１０】ガス供給手段から前記第２の真空槽６ｂに
ガスソース（Ｓｉ2 Ｈ6 ）を供給し基板にＳｉの薄膜を
形成する処理を終了し、基板保持手段１は下降させら
れ、基板保持手段１に搭載させられているＳｉ基板は図
示しない搬送アームにより，同じく図示しない基板交換
室に搬送され取り出される。そして次に処理すべきＳｉ
基板が真空容器６まで搬送され、搬送アームにより下降
した状態にある基板保持手段１の段差部１ａに搭載さ
れ、基板保持手段１は図１のようにセットされる。な
お、搬送の際は仕切り板としてのＳｉ基板２が無いた
め、真空槽６ａと６ｂの間の圧力は同じになる。搬送ア
ームおよび基板交換室は図１の紙面の後方または前方に
設置される。この実施例は真空容器の上面形状を円形と
した場合を示してあるが、他の形状であっても良い。The process of supplying a gas source (Si 2 H 6 ) from the gas supply means to the second vacuum chamber 6b to form a thin film of Si on the substrate is completed, and the substrate holding means 1 is lowered to hold the substrate. The Si substrate mounted on the means 1 is transferred to a substrate exchange chamber (not shown) by a transfer arm (not shown) and is taken out. And Si to be processed next
The substrate is transported to the vacuum vessel 6, and is mounted on the stepped portion 1a of the substrate holding means 1 which is lowered by the transport arm, and the substrate holding means 1 is set as shown in FIG. During the transfer, the pressure between the vacuum chambers 6a and 6b is the same because there is no Si substrate 2 as a partition plate. The transfer arm and the substrate exchange chamber are installed behind or in front of the plane of FIG. This embodiment shows a case where the top surface of the vacuum vessel is circular, but may have another shape.
【００１１】図２は図１の装置において、ガス供給手段
であるガスノズル８を通じて処理側真空槽６ｂにチッソ
ガスを導入した場合のヒータ側真空槽６ａと処理側真空
槽６ｂの圧力変化を示したグラフである。図２におい
て、○は室温で圧力測定を行った場合、×は基板温度を
９００℃に加熱して圧力測定を行った場合をそれぞれ示
しており、縦軸は真空槽６ａ，横軸は真空槽６ｂの圧力
をそれぞれ示している。この図から明らかなように真空
槽６ａと６ｂとでは２桁以上の差圧が生じることが理解
できる。さらに基板加熱を行うという条件を加えても基
板および基板保持手段による仕切り板効果が充分あるこ
とが判明した。さらに、ヒータ側真空槽６ａに設置され
たターボ分子ポンプ７の排気能力は、処理側真空槽６ｂ
に設置されたターボ分子ポンプの排気能力より小さい。
それにもかかわらずヒータ側真空槽６ａの方が２桁も真
空度が高い。このことからも基板２および基板保持手段
１による仕切りによる効果が大きいことが伺える。この
ような測定結果より、導入ガスが基板加熱装置周辺に回
り込む量が非常に少なく、基板加熱装置の寿命および熱
輻射の均一性が保たれることは明白である。FIG. 2 is a graph showing pressure changes in the heater-side vacuum tank 6a and the processing-side vacuum tank 6b when nitrogen gas is introduced into the processing-side vacuum tank 6b through the gas nozzle 8 as gas supply means in the apparatus of FIG. It is. 2. In FIG. 2, .largecircle. Indicates the case where the pressure was measured at room temperature, and x indicates the case where the pressure was measured by heating the substrate to 900.degree. C., the vertical axis being the vacuum chamber 6a, and the horizontal axis being the vacuum chamber. 6b respectively. As is apparent from this figure, it can be understood that a pressure difference of two digits or more occurs between the vacuum chambers 6a and 6b. It has been found that the partition plate effect by the substrate and the substrate holding means is sufficient even when the condition of heating the substrate is added. Further, the exhaust capacity of the turbo-molecular pump 7 installed in the heater-side vacuum tank 6a depends on the processing-side vacuum tank 6b.
Smaller than the pumping capacity of the turbo-molecular pump installed in
Nevertheless, the heater-side vacuum chamber 6a has a two-digit higher degree of vacuum. This also indicates that the effect of the partition by the substrate 2 and the substrate holding means 1 is large. From these measurement results, it is clear that the amount of the introduced gas flowing around the substrate heating device is extremely small, and the life of the substrate heating device and the uniformity of heat radiation are maintained.
【００１２】図３はジシランガスを用いてシリコンのエ
ピタキシャル成長を行わせた場合、その成長回数に対す
る基板表面上の塵の数の変化を測定したグラフである。
この測定に使用した基板は実際の生産で用いられる酸化
膜によるパターン付きのものである。この基板を用いた
理由は基板保持手段と基板の付着を回避するためであ
る。図３において、白い丸は基板保持手段１として、基
板２と同じ材料のＳｉを用い完全に仕切られている場合
についての成長回数の増加に対する塵の数の変化、黒い
丸は比較のために基板保持手段１として石英を用い、仕
切り部材６ｃを除去し他は全く同じ条件で処理を行った
結果を示している。この図からＳｉの基板保持手段を用
い，仕切られている場合には塵の数が成長を繰り返して
もほとんど変化が観られないのに対し、仕切りのない場
合はある成長回数を越えると塵の数が急激に増加すると
いうことが理解できる。すなわち図３は、基板保持手段
１を石英とし，仕切り板のない場合Ｓｉ薄膜の成長回数
が１４０回程度を越えると塵の数が急増することを示し
ている。FIG. 3 is a graph showing a change in the number of dusts on the substrate surface with respect to the number of times of growth when silicon is epitaxially grown using disilane gas.
The substrate used for this measurement is provided with a pattern of an oxide film used in actual production. The reason for using this substrate is to avoid adhesion between the substrate holding means and the substrate. In FIG. 3, white circles indicate changes in the number of dusts with respect to an increase in the number of times of growth in the case where the substrate holding means 1 is completely partitioned using Si of the same material as the substrate 2, and black circles indicate the substrate for comparison. This shows the result obtained by using quartz as the holding means 1, removing the partition member 6c, and performing the processing under exactly the same conditions. From this figure, the Si substrate holding means is used, and when the partition is used, the number of dusts hardly changes even if the growth is repeated, whereas when no partition is used, the number of dusts increases when the number of growth exceeds a certain number of times. It can be seen that the number increases rapidly. That is, FIG. 3 shows that when the substrate holding means 1 is made of quartz and there is no partition plate, when the number of times of growth of the Si thin film exceeds about 140 times, the number of dust increases rapidly.
【００１３】仕切り板のない場合、図６に示したような
石英製の受け皿１３（ヒータ３を保持するためのもの）
に第１の空間に回り込んだジシランガスが付着してＳｉ
薄膜が成長する。３００回繰替えしの成長を行ったあと
で前記石英製の受け皿１３を外して検討した結果、均一
に付着した銀色の膜が部分的に剥離して一部は欠け落ち
ている様子が観察できた。このＳｉ膜の剥離したもの
が、塵の原因であるといえる。図３に示すように、１４
０回以上の成長回数を越えると塵の数が急増するのは、
石英製受皿１３に堆積したＳｉ薄膜がある膜厚に達した
ときに欠け落ちを開始することによると考えられる。つ
まり、Ｓｉと石英の材質の相違により、応力が生じ、そ
れが剥離の原因となると考えられる。石英上では異質物
であるため、ある厚さを越えると膨張係数の差等に原因
して薄膜形成の一回ごとに異質物間で発生する歪み応力
でＳｉ膜にひびがはいり剥離が始まる。石英基板保持手
段１３から剥離しＳｉ薄膜が塵の発生する原因となる。
しかし、成長する薄膜が堆積する下地とが同質であれば
同化して応力が生じることはない。すなわち、Ｓｉ基板
保持手段上に付着したＳｉは、エピタキシャル成長して
基板保持手段と同化してしまうことによると考えられ
る。したがって、堆積した薄膜が剥離することはない。
このことは図３に示すように、仕切りがあり、かつシリ
コン製の支持部材の場合は非常に塵の発生が少ないこと
により裏付けられる。When there is no partition plate, a quartz tray 13 as shown in FIG. 6 (for holding the heater 3)
Disilane gas that has entered the first space adheres to the
A thin film grows. 300 times Kurikae Shi result after performing the growth was studied by removing the quartz pan 13, how the silver-colored film was uniformly adhered is down missing some partially peeling observed did it. It can be said that the delamination of the Si film is the cause of the dust. As shown in FIG.
When the number of times of growth exceeds zero or more, the number of dust increases rapidly.
It is considered that chipping starts when the Si thin film deposited on the quartz tray 13 reaches a certain film thickness. That is, it is considered that stress is generated due to the difference in the material of Si and quartz, and this causes peeling. Since the material is a foreign material on quartz, if the thickness exceeds a certain thickness, the Si film is cracked by a strain stress generated between the foreign materials each time a thin film is formed due to a difference in expansion coefficient or the like, and peeling starts. The Si thin film peeled off from the quartz substrate holding means 13 causes dust to be generated.
However, if the underlying film on which the growing thin film is deposited is of the same quality, no assimilation occurs and no stress is generated. That is, it is considered that Si attached to the Si substrate holding means is epitaxially grown and assimilated with the substrate holding means. Therefore, the deposited thin film does not peel off.
This is supported by the fact that there is a partition as shown in FIG. 3, and in the case of a support member made of silicon, the generation of dust is very small.
【００１４】図４はシリコンのエピタキシャル成長膜中
のカーボン濃度の深さ方向ＳＩＭＳ（２次イオン質量分
析）分析を行った結果を示すグラフである。図４（ａ）
は本発明装置による場合を示すもので、比較のために図
４（ｂ）に従来装置による場合を示している。両者を比
較すると、Ｂ（ボロン）、Ｏ（酸素）濃度はともに同じ
曲線になるが、Ｃ（炭素）濃度は仕切り板のある方が明
らかに少なく、基板加熱装置側から飛来するＣ（炭素）
の遮蔽に効果があるといえる。FIG. 4 is a graph showing the results of SIMS (secondary ion mass spectrometry) analysis of the carbon concentration in the silicon epitaxially grown film in the depth direction. FIG. 4 (a)
FIG. 4B shows a case using the apparatus of the present invention, and FIG. 4B shows a case using the conventional apparatus for comparison. Comparing the two, the B (boron) and O (oxygen) concentrations both have the same curve, but the C (carbon) concentration is clearly lower with the partition plate, and the C (carbon) flying from the substrate heating apparatus side is lower.
It can be said that it is effective in shielding the air.
【００１５】図７にさらに他の基板保持手段の実施例を
示す。この実施例では基板保持手段は基板２を支える支
持リング１ｄと基板２を上方向に移動させるためのキャ
リッジ１ｅから構成されている。支持リング１ｄは前述
した仕切り用のリム６ｃと同様な働きをする６ｄにより
支持される。キャリッジ１ｅに結合されている支柱４は
図１を参照して説明した支柱と同様に真空容器６の外部
に設けられた直線導入機５により昇降させられる。なお
この場合加熱手段も上方に退避できるようにしてある。
この構成によれば、支持リング１ｄと基板２との接触部
Ａは、基板２の自重により密着させられる。仕切り用の
リム６ｄと支持リング１ｄとの接触部Ｂも、１ｄと基板
との重さにより密着させることができる。図１の基板保
持手段の構造では、基板保持手段１の位置を正確に保
ち，６ｃと１ｂを密着させ密封度を向上させるために、
直線導入機５を微妙に制御する必要が合ったがこの実施
例ではそれほど精密に直線導入機５を制御する必要がな
い。FIG. 7 shows still another embodiment of the substrate holding means. In this embodiment, the substrate holding means comprises a support ring 1d for supporting the substrate 2 and a carriage 1e for moving the substrate 2 upward. The support ring 1d is supported by 6d having the same function as the above-described partition rim 6c. The column 4 connected to the carriage 1e is moved up and down by a linear introducer 5 provided outside the vacuum vessel 6, similarly to the column described with reference to FIG. In this case, the heating means can also be retracted upward.
According to this configuration, the contact portion A between the support ring 1d and the substrate 2 is brought into close contact with the substrate 2 by its own weight. The contact portion B between the partitioning rim 6d and the support ring 1d can also be brought into close contact with each other due to the weight of the substrate 1d and the weight. In the structure of the substrate holding means of FIG. 1, in order to maintain the position of the substrate holding means 1 accurately, to bring 6c and 1b into close contact with each other, and to improve the degree of sealing,
Although it was necessary to finely control the straight line introducing machine 5, in this embodiment, it is not necessary to control the straight line introducing machine 5 so precisely.
【００１６】[0016]
【発明の効果】以上、説明したように本発明による薄膜
形成方法は、真空排気手段により排気される真空容器の
基板保持手段に基板を設置し、基板を基板加熱手段によ
り加熱しつつ真空容器内に原料ガスを供給して薄膜を堆
積する薄膜形成方法において、堆積する薄膜と同じ物質
で構成された基板保持手段を用いて薄膜の堆積を行うも
のである。また、本発明による真空成膜装置は、真空槽
を加熱装置側と処理側に分け、それらの間を基板および
基板保持手段で隔て、加熱装置側真空槽と処理側真空槽
とを別々に排気してそれらの間に差圧を作り、基板保持
手段を形成する材料には、その基板上に堆積する薄膜と
同じ物質で構成したものである。したがって、本発明に
よれば、1)ソースガスの基板加熱装置側への飛来を防
ぎ、2)基板加熱周囲への生成物の付着を防ぎ、3)基板加
熱装置に生成物が付着しなくなる結果、基板加熱装置の
寿命が伸び、4)膜の付着によって生じる輻射の不均一性
がなくなり、均一な膜厚の薄膜が得られるとともに5)塵
の発生を無くすことができる。図５にジシラン（Ｓｉ2
Ｈ6 ）ガスの流量が変化したときのヒータ側真空槽６ａ
と処理側真空槽６ｂの圧力変化を示してある。基板加熱
用ヒータ３によりＳｉ基板２を約８６０℃に加熱した。
Ｓｉ2 Ｈ6 ガスの流量を変化させたときに、Ｓｉ基板２
上にＳｉ薄膜がエピタキシャル成長した。このような処
理（反応ガスの導入）を行っていてもヒータ側真空槽６
ａと処理側真空槽６ｂとに２桁以上の差圧が生じてい
る。このことから、Ｓｉ2 Ｈ6 ガスがヒータ側真空槽６
ａにまわり込む可能性が非常に少ないといえる。したが
って、基板加熱用ヒータ３に薄膜が生成し、ヒータの性
能が劣化することはない。なお、図３に比べて、ヒータ
側真空槽６ｂは３桁程圧力が高い。これは、Ｓｉ2Ｈ6
ガスが基板の熱によって分解反応し、その際Ｈ2 分子が
発生するからである。分解反応により発生したＨ2 分子
が、Ｓｉ基板２と基板保持手段１との間のすきまからヒ
ータ側真空槽６ｂに侵入するからと考えられる。さらに
本発明で加熱手段を有する真空槽に排気手段を有するこ
とには下記の特徴があると考える。1)加熱部に飛来する
ソースガス分子を低減できる。したがって、付着物を生
成するようなソースガス（特に熱分解して付着物を生成
するソースガス）を用いた場合、基板加熱まわりへの付
着物を少なくすることができる。2)加熱部より発生する
ガス分子の基板への回り込みを低減化できる。As described above, according to the thin film forming method of the present invention, the substrate is set on the substrate holding means of the vacuum vessel evacuated by the vacuum evacuation means, and the substrate is heated by the substrate heating means while the inside of the vacuum vessel is heated. In a thin film forming method for depositing a thin film by supplying a raw material gas to the thin film, the thin film is deposited using a substrate holding means made of the same substance as the thin film to be deposited. Further, in the vacuum film forming apparatus according to the present invention, the vacuum chamber is divided into a heating apparatus side and a processing side, and the space therebetween is separated by a substrate and a substrate holding means, and the heating apparatus side vacuum chamber and the processing side vacuum chamber are separately evacuated. Then, a differential pressure is created between them, and the material forming the substrate holding means is made of the same substance as the thin film deposited on the substrate. Therefore, according to the present invention, 1) preventing the source gas from coming to the substrate heating device side, 2) preventing the product from adhering around the substrate heating, and 3) preventing the product from adhering to the substrate heating device. In addition, the life of the substrate heating device is extended, 4) non-uniformity of radiation caused by film adhesion is eliminated, a thin film having a uniform thickness is obtained, and 5) generation of dust can be eliminated. FIG. 5 shows disilane (Si 2
H 6 ) Heater side vacuum tank 6a when gas flow rate changes
And the pressure change in the processing-side vacuum tank 6b. The Si substrate 2 was heated to about 860 ° C. by the substrate heating heater 3.
When the flow rate of the Si 2 H 6 gas is changed, the Si substrate 2
An Si thin film was epitaxially grown thereon. Even if such processing (introduction of reaction gas) is performed, the heater side vacuum tank 6
a and a pressure difference of two digits or more is generated between the processing-side vacuum chamber 6b and the processing-side vacuum chamber 6b. From this, the Si 2 H 6 gas is supplied to the heater side vacuum tank 6.
It can be said that there is a very low possibility of going around a. Therefore, a thin film is not formed on the substrate heating heater 3 and the performance of the heater does not deteriorate. It should be noted that the pressure in the heater-side vacuum chamber 6b is higher by about three digits than in FIG. This is Si 2 H 6
This is because the gas undergoes a decomposition reaction due to the heat of the substrate, generating H 2 molecules at that time. It is considered that H 2 molecules generated by the decomposition reaction enter the heater-side vacuum tank 6b from the gap between the Si substrate 2 and the substrate holding means 1. Further, it is considered that the present invention has the following features in having the exhaust means in the vacuum chamber having the heating means. 1) Source gas molecules flying to the heating section can be reduced. Therefore, when a source gas that generates an adhering substance (particularly, a source gas that generates an adhering substance by thermal decomposition) is used, the amount of the adhering substance around the substrate can be reduced. 2) It is possible to reduce the gas molecules generated from the heating section from flowing into the substrate.
【図１】本発明による薄膜形成方法および真空成膜装置
の実施例を説明するための図で、真空成膜装置を一部断
面で示した正面図である。FIG. 1 is a view for explaining an embodiment of a thin film forming method and a vacuum film forming apparatus according to the present invention, and is a front view showing a partial cross section of the vacuum film forming apparatus.
【図２】ガスノズルより第２の真空槽に空気を導入した
場合の第１，第２の真空槽の圧力変化を示すグラフであ
る。FIG. 2 is a graph showing pressure changes in the first and second vacuum tanks when air is introduced from a gas nozzle into a second vacuum tank.
【図３】ジシランガスを用いてシリコンのエピタキシャ
ル成長を行わせた場合、その成長回数に対する基板表面
上の塵の数を示したグラフである。FIG. 3 is a graph showing the number of dusts on the substrate surface with respect to the number of times that silicon is epitaxially grown using disilane gas.
【図４】シリコンのエピタキシャル成長膜中のカーボン
濃度の深さ方向ＳＩＭＳ分析を行った結果を示すグラフ
で、（ａ）は本発明の装置による場合を、（ｂ）は従来
装置による場合をそれぞれ示している。4A and 4B are graphs showing the results of a SIMS analysis of the carbon concentration in a silicon epitaxially grown film in the depth direction. FIG. 4A shows the case of the apparatus of the present invention, and FIG. 4B shows the case of the conventional apparatus. ing.
【図５】ジシランガスの流量を変化させたときの第１お
よび第２の真空槽の圧力変化を示すグラフである。FIG. 5 is a graph showing pressure changes in first and second vacuum tanks when a flow rate of disilane gas is changed.
【図６】加熱手段の実施例の外観を示す図である。FIG. 6 is a view showing the appearance of an embodiment of a heating means.
【図７】基板保持手段の他の実施例を示す図である。FIG. 7 is a view showing another embodiment of the substrate holding means.
１ 基板保持手段 ２ 基板 ３ 基板加熱用ヒータ ４ 支柱 ５ 直線導入機 ６ 真空容器 ７，９ ターボ分子ポンプ ８ ガスノズル １０ 直流電源 １１ ホルダ １２ 容器 １３ 受け皿 ２２ ガイド板 DESCRIPTION OF SYMBOLS 1 Substrate holding means 2 Substrate 3 Heater for substrate heating 4 Prop 5 Linear introduction machine 6 Vacuum container 7, 9 Turbo molecular pump 8 Gas nozzle 10 DC power supply 11 Holder 12 Container 13 Receiving tray 22 Guide plate
───────────────────────────────────────────────────── フロントページの続き (72)発明者 村上 俊一 東京都府中市四谷５丁目８番１号 日電 アネルバ株式会社内 (72)発明者 室田 裕義 東京都府中市四谷５丁目８番１号 日電 アネルバ株式会社内 (72)発明者 辰己 徹 東京都港区芝五丁目７番１号 日本電気 株式会社内 (56)参考文献 特開 昭64−11320（ＪＰ，Ａ) (58)調査した分野(Int.Cl.6，ＤＢ名) H01L 21/205 C30B 25/12 C30B 25/18 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Shunichi Murakami 5-8-1, Yotsuya, Fuchu-shi, Tokyo Nidec Anelva Co., Ltd. (72) Inventor Hiroyoshi Murota 5-81-1, Yotsuya, Fuchu-shi, Tokyo Nidec Anelva (72) Inventor Toru Tatsumi 5-7-1 Shiba, Minato-ku, Tokyo NEC Corporation (56) References JP-A-64-11320 (JP, A) (58) Fields surveyed (Int .Cl. 6 , DB name) H01L 21/205 C30B 25/12 C30B 25/18
Claims (10)
の基板保持手段に基板を設置し、当該基板を基板加熱手
段により加熱しつつ前記真空容器内に原料ガスを供給し
て薄膜を堆積する薄膜形成方法において、 堆積する薄膜と同じ物質で構成された基板保持手段を用
いて薄膜の堆積を行うことを特徴とする薄膜形成方法。1. A thin film for depositing a thin film by placing a substrate on a substrate holding means of a vacuum vessel evacuated by a vacuum exhaust means and supplying a source gas into the vacuum vessel while heating the substrate by a substrate heating means. A method for forming a thin film, comprising: depositing a thin film using a substrate holding means made of the same substance as the thin film to be deposited.
中に、基板保持手段と、当該基板保持手段に保持された
基板を加熱する基板加熱手段とを有し、前記基板保持手
段を形成する材料は、前記基板上に堆積する薄膜と同じ
物質で構成されていることを特徴とする真空成膜装置。2. A material for forming the substrate holding means, comprising a substrate holding means and a substrate heating means for heating a substrate held by the substrate holding means in a vacuum container evacuated by the vacuum evacuation means. Is formed of the same material as the thin film deposited on the substrate.
空容器と、 前記第１の真空槽と前記第２の真空槽それぞれに連通す
る第１および第２の真空排気手段と、 前記第１の真空槽に設けられた基板加熱手段と、 前記第２の真空槽に設けられたガス供給手段と、 基板の薄膜形成面を第２の真空槽に向けて保持し、前記
基板とともに前記第１および第２の真空槽を分離する位
置に配置される基板保持手段とから構成され、前記基板
保持手段を形成する材料は、その基板上に堆積する薄膜
と同じ物質で構成されていることを特徴とする真空成膜
装置。3. A vacuum vessel having first and second vacuum vessel spaces; first and second vacuum exhaust means communicating with the first vacuum vessel and the second vacuum vessel, respectively; A substrate heating means provided in the first vacuum chamber; a gas supply means provided in the second vacuum chamber; and a thin film forming surface of the substrate held toward the second vacuum chamber. Substrate holding means arranged at a position separating the first and second vacuum chambers, wherein the material forming the substrate holding means is formed of the same substance as the thin film deposited on the substrate. Characteristic vacuum film forming equipment.
し，上下方向に移動可能であり、前記真空容器の内壁に
設けられた前記第１および第２の真空槽を分離する仕切
り位置に設けられた仕切り用の部材に密着させられる部
材である請求項３記載の真空成膜装置。4. The substrate holding means holds the substrate in close contact and is movable in a vertical direction, and is provided at a partition position for separating the first and second vacuum tanks provided on the inner wall of the vacuum vessel. The vacuum film forming apparatus according to claim 3, wherein the vacuum film forming apparatus is a member that is brought into close contact with the provided partitioning member.
るために前記真空容器の大気側で操作可能に設けられた
運動導入手段を設置した請求項３記載の真空成膜装置。5. The vacuum film forming apparatus according to claim 3, further comprising a motion introducing means operably provided on the atmosphere side of said vacuum vessel for moving said substrate holding means and exchanging substrates.
求項３記載の真空成膜装置。6. The vacuum film forming apparatus according to claim 3, wherein said substrate heating means is an electric heater.
スを放出するノズルである請求項３記載の真空成膜装
置。7. The vacuum film forming apparatus according to claim 3, wherein said gas supply means is a nozzle for discharging a gas toward said substrate.
それぞれに設置された真空排気手段は、ターボ分子ポン
プである請求項３記載の真空成膜装置。8. The vacuum film forming apparatus according to claim 3, wherein the vacuum exhaust means provided in each of the first vacuum chamber and the second vacuum chamber is a turbo molecular pump.
手段の排気能力は、前記第２の真空槽に配置された前記
真空槽排気手段の排気能力より小さいものである請求項
３記載の真空成膜装置。9. The exhaust capacity of the vacuum exhaust means provided in the first vacuum chamber is smaller than the exhaust capacity of the vacuum exhaust means arranged in the second vacuum chamber. Vacuum deposition equipment.
キシャルＳｉ薄膜である請求項３記載の真空成膜装置。10. The vacuum film forming apparatus according to claim 3, wherein the thin film deposited on the substrate is an epitaxial Si thin film.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3212696A JP2983084B2 (en) | 1990-09-21 | 1991-07-30 | Thin film forming method and vacuum film forming apparatus using this method |
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2-253191 | 1990-09-21 | ||
| JP25319190 | 1990-09-21 | ||
| JP3212696A JP2983084B2 (en) | 1990-09-21 | 1991-07-30 | Thin film forming method and vacuum film forming apparatus using this method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH053161A JPH053161A (en) | 1993-01-08 |
| JP2983084B2 true JP2983084B2 (en) | 1999-11-29 |
Family
ID=26519370
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3212696A Expired - Fee Related JP2983084B2 (en) | 1990-09-21 | 1991-07-30 | Thin film forming method and vacuum film forming apparatus using this method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2983084B2 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06244269A (en) * | 1992-09-07 | 1994-09-02 | Mitsubishi Electric Corp | Semiconductor manufacturing apparatus, wafer vacuum chuck device thereof, and gas cleaning and nitride film formation therefor |
| KR970066703A (en) * | 1996-03-05 | 1997-10-13 | 이우복 | Hard mask aligner |
| JP3796030B2 (en) | 1997-11-16 | 2006-07-12 | キヤノンアネルバ株式会社 | Thin film production equipment |
-
1991
- 1991-07-30 JP JP3212696A patent/JP2983084B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH053161A (en) | 1993-01-08 |
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