JP3081886B2 - Film formation method - Google Patents
Film formation methodInfo
- Publication number
- JP3081886B2 JP3081886B2 JP05189395A JP18939593A JP3081886B2 JP 3081886 B2 JP3081886 B2 JP 3081886B2 JP 05189395 A JP05189395 A JP 05189395A JP 18939593 A JP18939593 A JP 18939593A JP 3081886 B2 JP3081886 B2 JP 3081886B2
- Authority
- JP
- Japan
- Prior art keywords
- reaction vessel
- gas
- temperature
- nitriding
- oxide film
- 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.)
- Expired - Fee Related
Links
Landscapes
- Formation Of Insulating Films (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は、成膜方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film forming method.
【０００２】[0002]
【従来の技術】従来から、半導体デバイスの製造工程に
おいて、ポリシリコン膜、アモルファスシリコン膜等の
シリコン被膜、ＰＳＧ膜、ＢＰＳＧ膜等のシリコン酸化
膜、あるいはシリコン窒化膜等の被膜を減圧ＣＶＤや常
圧ＣＶＤ等の処理によって半導体ウエハ等の被処理体へ
成膜することが広く行なわれている。2. Description of the Related Art Conventionally, in the process of manufacturing a semiconductor device, a silicon film such as a polysilicon film or an amorphous silicon film, a silicon oxide film such as a PSG film or a BPSG film, or a film such as a silicon nitride film has been conventionally subjected to a low pressure CVD or a conventional method. 2. Description of the Related Art Film formation on an object to be processed such as a semiconductor wafer by a process such as pressure CVD is widely performed.
【０００３】このような成膜工程では、例えば、熱処理
装置などによる半導体ウエハのバッチ処理が広く行なわ
れている。例えばＭＯＳトランジスタのゲート酸化膜を
成膜する際には熱処理装置が用いられる。この熱処理装
置を用いる場合には、所定の熱処理温度に保持された反
応容器内に多数枚の半導体ウエハ等の被処理体を石英等
のセラミックスからなる熱処理ボートを介して収納し、
常圧下で反応容器内へ酸素ガスあるいは水蒸気を導入
し、ドライ酸化あるいはウェット酸化によってゲート酸
化膜としてシリコン酸化膜の成膜が行なわれている。ま
た、一方では最近の半導体装置の高集積化によりその配
線構造が微細化、薄膜化し、ＭＯＳトランジスタにおけ
るゲート酸化膜も益々薄膜化して来ているため、ゲート
酸化膜の絶縁耐性が重要な課題になっている。そこで、
酸化処理後の半導体ウエハの酸化膜を更に窒素ガス雰囲
気あるいはアンモニアガス雰囲気下でアニール処理して
酸化膜中に窒素原子を拡散させ、ゲート酸化膜の絶縁耐
性等の電気的特性を高めるためることがある。In such a film forming process, for example, batch processing of a semiconductor wafer by a heat treatment apparatus or the like is widely performed. For example, when forming a gate oxide film of a MOS transistor, a heat treatment apparatus is used. When using this heat treatment apparatus, a large number of objects to be processed such as semiconductor wafers are accommodated in a reaction vessel maintained at a predetermined heat treatment temperature via a heat treatment boat made of ceramics such as quartz,
Oxygen gas or water vapor is introduced into a reaction vessel under normal pressure, and a silicon oxide film is formed as a gate oxide film by dry oxidation or wet oxidation. On the other hand, the wiring structure has become finer and thinner due to the recent high integration of semiconductor devices, and the gate oxide film in MOS transistors has become increasingly thinner. Has become. Therefore,
The oxide film of the oxidized semiconductor wafer may be further annealed in a nitrogen gas atmosphere or an ammonia gas atmosphere to diffuse nitrogen atoms in the oxide film and to improve electrical characteristics such as insulation resistance of the gate oxide film. is there.
【０００４】[0004]
【発明が解決しようとする課題】しかしながら、従来の
成膜方法は、酸化処理後の半導体ウエハを熱処理装置か
ら一旦外部にアンロードし、酸化処理後の半導体ウエハ
を別の熱処理装置で窒化処理するようにしているため、
アンロード時に半導体ウエハが空気に触れ、空気中の不
純物あるいはパーティクルが混入する虞があり、ゲート
酸化膜の膜質が劣化するなどという課題があった。However, in the conventional film forming method, the oxidized semiconductor wafer is temporarily unloaded from the heat treatment apparatus to the outside, and the oxidized semiconductor wafer is nitrided by another heat treatment apparatus. So that
At the time of unloading, the semiconductor wafer may come into contact with air and impurities or particles in the air may be mixed into the semiconductor wafer, causing a problem that the quality of the gate oxide film is deteriorated.
【０００５】また、従来の成膜方法として、マルチチャ
ンバーからなる真空処理装置による枚葉処理により半導
体ウエハにゲート酸化膜を形成する方法もあるが、この
方法では熱酸化処理と比較して低温下で半導体ウエハを
処理するため、酸化膜の膜質が緻密でないなど必ずしも
良好なものとは言い難く、それだけ絶縁耐性等の電気的
特性に劣り、今後の超薄膜化傾向に対処できないという
課題があった。As a conventional film forming method, there is also a method of forming a gate oxide film on a semiconductor wafer by single-wafer processing using a vacuum processing apparatus comprising a multi-chamber. In order to process a semiconductor wafer, it is difficult to say that the quality of the oxide film is not very good, for example, the film quality is not dense, and the electrical characteristics such as insulation resistance are inferior. .
【０００６】本発明は、上記課題を解決するためになさ
れたもので、被処理体に対して酸化処理、窒化処理及び
脱水素処理を短時間で行なうことができ、しかも空気中
のパーティクル等の不純物がゲート酸化膜等の酸化膜中
に混入することがなく極薄且つ緻密な膜質で絶縁耐性等
の電気的特性に優れた酸化膜を被処理体に形成すること
ができる成膜方法を提供することを目的としている。[0006] The present invention has been made to solve the above problems, the oxidation process to the object to be processed, nitriding and
Dehydrogenation process can be performed in a short time, and in the air
Impurities such as particles in oxide film such as gate oxide film
It is an object of the present invention to provide a film formation method capable of forming an oxide film having an extremely thin and dense film quality and excellent in electrical characteristics such as insulation resistance on a processing object without being mixed into a substrate.
【０００７】[0007]
【課題を解決するための手段】本発明の請求項１に記載
の成膜方法は、外部ヒータにより加熱して所定の酸化処
理温度まで昇温させた反応容器内へ所定の酸化処理用ガ
スを供給する工程と、上記反応容器内で保持具により保
持された複数の被処理体の表面を酸化処理用ガスにより
酸化させて酸化膜を形成する工程と、上記反応容器内の
酸化処理用ガスを所定の窒化処理用ガスで置換する工程
と、上記外部ヒータにより上記反応容器内を所定の窒化
処理温度まで加熱して上記酸化膜に窒化処理を施す工程
と、上記反応容器内の窒化処理用ガスを塩化水素ガスを
含む酸素ガスと置換する工程と、上記外部ヒータにより
上記反応容器内を上記窒化処理温度より高い温度まで加
熱して窒化処理により上記酸化膜に混入した水素原子を
除去する脱水素処理を施す工程とを備え、上記反応容器
内からその外部へ上記各被処理体を取り出すことなく上
記各工程を連続して行うようにしたものである。According to a first aspect of the present invention, there is provided a film forming method, wherein a predetermined oxidizing treatment is performed by heating with an external heater.
A step of supplying the physical temperature to warm to cause the reaction vessel to a predetermined oxidation gas, and a surface of the plurality of the object held by the holder in the reaction vessel was oxidized by oxidizing processing gas forming an oxide film, in the reaction vessel
A step of replacing the oxidizing gas with a predetermined nitriding gas
And a step of performing a nitriding treatment on the oxide film is heated by the external heater the reaction vessel to a predetermined nitriding temperature
And the nitriding gas in the reaction vessel is replaced with hydrogen chloride gas.
Replacing with oxygen gas containing, and the above-mentioned external heater
The inside of the reaction vessel is heated to a temperature higher than the nitriding temperature.
Hydrogen atoms mixed into the above oxide film by heating and nitriding
Performing a dehydrogenation treatment for removing the reaction vessel,
Without removing each of the above objects from inside to outside
Each of the steps is performed continuously .
【０００８】[0008]
【作用】本発明の請求項１に記載の発明によれば、外部
ヒータにより反応容器を加熱してその内部を所定の酸化
処理温度まで昇温し、次いで反応容器内へ所定の酸化処
理用ガスを供給すると、反応容器内で保持具により保持
された複数の被処理体の表面で酸化処理用ガスによりシ
リコンを酸化してシリコン酸化膜を形成し、その後、被
処理体を反応容器から取り出すことなく窒化処理用ガス
で置換した後、外部ヒータにより反応容器内を加熱して
内部を所定温度（窒化処理温度）まで昇温すると、シリ
コン酸化膜内に窒素原子が熱拡散してシリコン酸化膜の
表面に窒化膜を形成する。引き続き、被処理体を反応容
器から取り出すことなく反応容器内の窒化処理用ガスを
塩化水素を含む酸素ガスで置換した後、外部ヒータによ
り反応容器内を加熱して窒化処理温度よりも高い温度ま
で昇温すると、酸素ガスにより窒化処理後に酸化膜に混
入している水素原子を表面から酸化し、更に酸化膜内の
水素原子を表面へ熱拡散させて酸化し、酸化膜内の水素
原子を除去する。According to the first aspect of the present invention, the reaction vessel is heated by the external heater to oxidize the inside of the reaction vessel to a predetermined level.
Until the processing temperature was heated, then it is supplied a predetermined oxidation gas into the reaction vessel, the interest by the plurality of surface oxidation gas of the workpiece held by the holder in a reaction vessel <br /> oxidizing the silicon to form a silicon oxide film, then the
After the treated body is replaced with the nitriding gas without being taken out of the reaction vessel, the inside of the reaction vessel is heated to a predetermined temperature (nitriding temperature) by heating the inside of the reaction vessel with an external heater, and nitrogen atoms are contained in the silicon oxide film. Thermal diffusion forms a nitride film on the surface of the silicon oxide film. Subsequently, the object to be treated is
The nitriding gas in the reaction vessel without taking it out of the reactor.
After replacing with oxygen gas containing hydrogen chloride, an external heater
Heating the reaction vessel to a temperature higher than the nitriding temperature.
When the temperature is increased by nitriding with oxygen gas,
Oxidizes the entered hydrogen atoms from the surface and further oxidizes
Hydrogen atoms are thermally diffused to the surface and oxidized, resulting in hydrogen in the oxide film.
Remove atoms .
【０００９】[0009]
【実施例】以下、図１〜図４に示す実施例に基づいて本
発明を説明する。まず、本実施例に好適に用いられる熱
処理装置について図１、図２を参照しながら説明する。
この熱処理装置は、図１に示すように、基台１０に垂直
に配設された加熱炉２０と、この加熱炉２０の内部に軸
芯を一致させて挿入、配置され且つ下端部が開口した反
応容器３０と、この反応容器３０内にロードされてこの
反応容器３０を封止し且つ例えば３０枚前後の被処理体
（以下、「半導体ウエハ」で代表する）Ｗを熱処理に供
する保持具（以下、「熱処理ボート」と称す）４０と、
この熱処理ボート４０で保持された半導体ウエハＷを反
応容器３０の外側から強制冷却する冷却装置５０とを備
えて構成されている。そして、この熱処理ボート４０
は、半導体ウエハＷの熱処理時に図示しない昇降機構を
介して矢印Ａ方向に昇降して反応容器３０内にロードさ
れ、半導体ウエハＷの熱処理後には反応容器３０からア
ンロードされるように構成されている。DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the embodiments shown in FIGS. First, a heat treatment apparatus suitably used in the present embodiment will be described with reference to FIGS.
As shown in FIG. 1, this heat treatment apparatus is provided with a heating furnace 20 disposed vertically to the base 10 and inserted and arranged inside the heating furnace 20 with their axes aligned and opened at the lower end. A reaction vessel 30 and a holder (for example, about 30 wafers (hereinafter, referred to as “semiconductor wafers”) W which are loaded into the reaction vessel 30 to seal the reaction vessel 30, and to perform heat treatment. Hereinafter, referred to as “heat treatment boat”) 40,
A cooling device 50 for forcibly cooling the semiconductor wafer W held by the heat treatment boat 40 from outside the reaction vessel 30 is provided. And this heat treatment boat 40
Is configured to be lifted and lowered in the direction of arrow A via a lifting mechanism (not shown) during the heat treatment of the semiconductor wafer W and loaded into the reaction vessel 30, and to be unloaded from the reaction vessel 30 after the heat treatment of the semiconductor wafer W. I have.
【００１０】上記加熱炉２０は、上端部が閉塞し、下端
部が開口した筒状体として形成されている。即ち、この
加熱炉２０は、図１に示すように、筒状体の直胴部内面
に取り付けられ且つ例えば二珪化モリブデン等からなる
外部ヒータ（例えば、コイル状の抵抗発熱体２１）と、
この抵抗発熱体２１を保持すると共に筒状体の直胴部及
び上端部の内面全面を被覆する断熱材２２と、この断熱
材２２の外面全面を被覆するステンレス等からなるシェ
ル（図示せず）とを備え、発熱量の大きな二珪化モリブ
デン等からなる抵抗発熱体２１によって反応容器３０内
の温度を例えば、５００〜１２００℃の範囲まで短時間
で加熱、制御し、その内部の半導体ウエハＷに対して所
定の熱処理を短時間で行なうように構成されている。ま
た、例えば二珪化モリブデンからなる抵抗発熱体２１
は、５０〜２００℃／分の平均昇温速度（以下、単に
「昇温速度」と称す。）で反応容器３０内を加熱できる
ように構成されている。昇温速度が５０℃／分未満では
不要な熱を長く印加する虞があって好ましくなく、ま
た、昇温速度が２００℃／分を超えると後述のリング状
支持体４１を介して半導体ウエハＷ全面を均等に加熱す
ることができず、面内に温度勾配が生じる虞があって好
ましくない。また、この二珪化モリブデンからなる抵抗
発熱体２１は、例えば１２００℃で２０Ｗ／cm２ とい
う大きな表面発熱負荷 を得ることができる。従って、
例えば線径が３.５mmという細い線であっても１ ００℃
／分の昇温速度で反応容器３０内を加熱することがで
き、また、細い線径のため後述する冷却装置５０による
強制冷却を併用することにより５０℃／分という平均降
温速度（以下、単に「降温速度」と称す。）で反応容器
３０内を冷却することができる。The heating furnace 20 is formed as a tubular body whose upper end is closed and whose lower end is open. That is, as shown in FIG. 1, the heating furnace 20 includes an external heater (for example, a coil-shaped resistance heating element 21) attached to the inner surface of a cylindrical body and made of, for example, molybdenum disilicide.
A heat insulating material 22 that holds the resistance heating element 21 and covers the entire inner surface of the cylindrical body and the upper end portion, and a shell (not shown) made of stainless steel or the like that covers the entire outer surface of the heat insulating material 22. The temperature inside the reaction vessel 30 is heated and controlled in a short time to, for example, a range of 500 to 1200 ° C. by the resistance heating element 21 made of molybdenum disilicide or the like having a large calorific value. On the other hand, a predetermined heat treatment is performed in a short time. Further, for example, the resistance heating element 21 made of molybdenum disilicide is used.
Is configured such that the inside of the reaction vessel 30 can be heated at an average heating rate of 50 to 200 ° C./min (hereinafter, simply referred to as “heating rate”). If the rate of temperature rise is less than 50 ° C./min, unnecessary heat may be applied for a long time, which is not preferable. If the rate of temperature rise is more than 200 ° C./min, the semiconductor wafer W is formed via a ring-shaped support 41 described later. It is not preferable because the entire surface cannot be heated evenly and a temperature gradient may occur in the surface. The resistance heating element 21 made of molybdenum disilicide can obtain a large surface heating load of, for example, 20 W / cm 2 at 1200 ° C. Therefore,
For example, even if the wire diameter is as thin as 3.5 mm, it is 100 ° C.
The temperature inside the reaction vessel 30 can be heated at a rate of temperature rise of 50 ° C./min, and the average temperature drop rate of 50 ° C./minute (hereinafter simply referred to as “ The inside of the reaction vessel 30 can be cooled by using a “cooling rate”.
【００１１】また、上記反応容器３０は、図１に示すよ
うに、上端部が閉塞し且つ下端部が開口した石英等の耐
熱、耐食性材料によって形成されている。そして、その
開口下端のやや上方に酸素ガス、水蒸気など酸化処理用
ガスあるいはアンモニアガス、亜酸化窒素ガスなどの窒
化処理用ガスを導入する、石英等の耐熱、耐食性の材料
からなるガス導入管３１が取り付けられ、このガス導入
管３１から酸化処理用ガスあるいは窒化処理用ガスを反
応容器３０内に供給してして半導体ウエハＷを酸化処理
あるいは窒化処理を施すように構成されている。このガ
ス導入管３１は反応容器３０の内面に沿って立ち上が
り、反応容器３０の直胴部の上端近傍でドーム状上面の
中心に向けて屈曲形成され、この中心部に酸化処理用ガ
スあるいは窒化処理用ガスを吹付け、ドーム状上面を介
して各処理用ガスを反応容器３０内全体に均等に拡散さ
せるように構成されている。また、この反応容器３０の
下端のやや上方にはガスを排気する排気管３２が取り付
けられており、この排気管３２を介して処理後のガスな
どを外部へ排気するように構成されている。As shown in FIG. 1, the reaction vessel 30 is made of a heat-resistant and corrosion-resistant material such as quartz having a closed upper end and an open lower end. A gas introduction pipe 31 made of a heat-resistant and corrosion-resistant material such as quartz for introducing an oxidizing gas such as oxygen gas or water vapor or a nitriding gas such as ammonia gas or nitrous oxide gas slightly above the lower end of the opening. A gas for oxidation treatment or a gas for nitridation treatment is supplied from the gas introduction pipe 31 into the reaction vessel 30 so that the semiconductor wafer W is subjected to oxidation treatment or nitridation treatment. The gas inlet tube 31 rises along the inner surface of the reaction vessel 30 and is bent toward the center of the dome-shaped upper surface in the vicinity of the upper end of the straight body of the reaction vessel 30. The processing gas is blown, and each processing gas is uniformly diffused throughout the reaction vessel 30 via the dome-shaped upper surface. An exhaust pipe 32 for exhausting gas is attached slightly above the lower end of the reaction vessel 30, and the processed gas and the like are exhausted to the outside via the exhaust pipe 32.
【００１２】上記熱処理ボート４０は、例えば、石英等
の耐熱性、耐食性に優れた材料によって形成され且つ３
０枚の半導体ウエハＷを１枚ずつ個別に支持する支持部
材（リング状支持体４１）（図２参照）と、これらのリ
ング状支持体４１を上下方向で等間隔を隔てて平行に支
持、固定する複数の支持棒４２と、これらの支持棒４２
の下端に接続され且つ石英等の耐熱性、耐食性に優れた
材料によって形成された保温体４３とを備え、この保温
体４３の底面４３Ａが上記反応容器３０の下端開口を閉
止するように構成されている。The heat treatment boat 40 is made of a material having excellent heat resistance and corrosion resistance such as quartz, for example.
A support member (ring-shaped support 41) (see FIG. 2) for individually supporting the zero semiconductor wafers W one by one, and these ring-shaped supports 41 are supported in parallel at equal intervals in the vertical direction. A plurality of support rods 42 to be fixed, and these support rods 42
And a heat insulator 43 formed of a material having excellent heat resistance and corrosion resistance such as quartz, and a bottom surface 43A of the heat insulator 43 is configured to close a lower end opening of the reaction vessel 30. ing.
【００１３】また、上記リング状支持体４１は、図２に
示すように、半導体ウエハＷを周縁部で支承する平坦面
を有する支承部４１Ａと、この支承部４１Ａと一体化し
て支持棒４２に固定される固定部４１Ｂとから形成され
ている。そして、上下のリング状支持体４１、４１の間
隔は、上下の半導体ウエハＷ（厚さ０.７mm）の肉厚方
向の中心間の距離が例えば９.５２５mmに設定されてい
る。また、上記支承部４１Ａは内径から外方へ行くほど
肉厚が漸次厚く形成され、外周ほど熱容量が大きくなる
ように構成されている。従って、従来のようにリング状
支持体４１がない場合には、反応容器３０の周側面から
の輻射熱が上下の半導体ウエハＷにより遮蔽され、輻射
熱が半導体ウエハＷの内方に入射せず、周縁部のみに入
射し、周縁部が内方より温度が高くなって面内で温度勾
配ができ、逆に、冷却時には加熱時と同様に隣合う上下
の半導体ウエハＷにより半導体ウエハＷ内方からの放熱
が阻害され、周縁部からの放熱が促進され、やはり面内
で温度勾配ができ、半導体ウエハＷにスリップや反りを
生じさせる。ところが、このリング状支持体４１がある
場合には、加熱時にはリング状支持体４１が徐々に加熱
されて半導体ウエハＷの周縁部の急激な温度上昇を抑制
して内方まで均等に加熱し、また冷却時にはリング状支
持体４１の蓄熱により周縁部の急激な冷却がなく、その
結果、半導体ウエハＷの面内で温度勾配を生じることな
く面内を均等に加熱、冷却できる。As shown in FIG. 2, the ring-shaped support 41 includes a support 41A having a flat surface for supporting the semiconductor wafer W at a peripheral portion, and a support rod 42 integrated with the support 41A. It is formed from a fixed portion 41B to be fixed. The distance between the upper and lower ring-shaped supports 41 is set such that the distance between the centers of the upper and lower semiconductor wafers W (thickness: 0.7 mm) in the thickness direction is, for example, 9.525 mm. The thickness of the support portion 41A is gradually increased from the inner diameter toward the outer side, and the heat capacity is increased toward the outer periphery. Therefore, when the ring-shaped support 41 is not provided as in the related art, the radiant heat from the peripheral side surface of the reaction vessel 30 is shielded by the upper and lower semiconductor wafers W, and the radiant heat does not enter the inside of the semiconductor wafer W. And the peripheral edge portion has a higher temperature than the inner side and a temperature gradient is formed in the plane. Conversely, when cooling, the upper and lower semiconductor wafers W are adjacent to each other in the same manner as during heating. The heat radiation is hindered, the heat radiation from the peripheral portion is promoted, and a temperature gradient also occurs in the plane, causing the semiconductor wafer W to slip or warp. However, when the ring-shaped support 41 is provided, the ring-shaped support 41 is gradually heated at the time of heating to suppress a rapid rise in the temperature of the peripheral portion of the semiconductor wafer W and heat the semiconductor wafer W evenly inward. Further, at the time of cooling, there is no rapid cooling of the peripheral portion due to the heat storage of the ring-shaped support body 41. As a result, the semiconductor wafer W can be uniformly heated and cooled without causing a temperature gradient within the surface.
【００１４】また、上記冷却装置５０は、上記加熱炉２
０と上記反応容器３０間の空隙部６０で冷気を流通させ
て反応容器３０内を強制冷却するように構成されてい
る。即ち、この冷却装置５０は、上記加熱炉２０の上面
中央に形成された排気口２３に排気ダクト５１を介して
連結された排気ファン５２と、上記空隙部６０の下端で
且つ加熱炉２０の下端周縁に等間隔に形成された複数の
吸気口５３と、これらの吸気口５３に連通する連通ダク
ト５４と、この連通ダクト５４に接続され、外部の空気
を連通ダクト５４を介して吸気口５３へ給気する給気フ
ァン５５とを備え、上記排気ファン５２及び上記給気フ
ァン５５の協働作用により上記空隙部６０内に図１の矢
印Ｂで示すように空気の上昇気流を形成し、この上昇気
流により例えば３０〜１００℃／分の降温速度で反応容
器３０内を冷却するように構成されている。降温速度が
３０℃／分未満では冷却速度が遅く、不要な熱を半導体
ウエハＷに印加する虞があって好ましくなく、また、降
温速度が１００℃／分を超えると上記リング状支持体４
１を介して半導体ウエハＷ全面を均等に強制冷却するこ
とができず、面内に温度勾配が生じる虞があって好まし
くない。また、上記各吸気口５３にはそれぞれ熱処理ボ
ート４０の最下段のリング状支持体４１まで達する給気
ノズル５６が取り付けられ、これらの給気ノズル５６に
より空隙部６０の周囲で均等な上昇気流を形成するよう
に構成されている。また、上記排気ダクト５１は工場内
の共用ダクト７０に連通し、上記排気ファン５２及び給
気ファン５５によって空隙部６０から排気された高温空
気を熱交換器５７で冷却しながら排気ダクト７０の排気
ファン７１によって図１の矢印Ｃで示すように外部へ排
出するように構成されている。また、上記排気口２３及
び上記吸気口５３にはそれぞれシャッター５８、５９が
配設され、熱処理時にはこれらのシャッター５８、５９
を閉じて空隙部６０を密閉し、反応容器３０を効率良く
加熱できるように構成されている。尚、上記排気口２３
のシャッター５８は例えば石英等の耐熱性材料によって
形成され、また、上記給気口５３のシャッター５９は例
えばステンレス、フッ素系樹脂等よって形成されてい
る。The cooling device 50 includes the heating furnace 2.
It is configured such that cool air is circulated through a gap 60 between the reaction vessel 30 and the reaction vessel 30 to forcibly cool the inside of the reaction vessel 30. That is, the cooling device 50 includes an exhaust fan 52 connected to an exhaust port 23 formed at the center of the upper surface of the heating furnace 20 via an exhaust duct 51, a lower end of the gap 60 and a lower end of the heating furnace 20. A plurality of intake ports 53 formed at equal intervals on a peripheral edge, a communication duct 54 communicating with these intake ports 53, and an external air connected to the communication duct 54 to the intake ports 53 via the communication duct 54. An air supply fan 55 for supplying air is formed, and an ascending airflow of air is formed in the gap portion 60 as shown by an arrow B in FIG. 1 by the cooperation of the exhaust fan 52 and the air supply fan 55. The inside of the reaction vessel 30 is configured to be cooled at a temperature decreasing rate of, for example, 30 to 100 ° C./min by the rising airflow. If the cooling rate is less than 30 ° C./min, the cooling rate is low, and there is a risk that unnecessary heat may be applied to the semiconductor wafer W, which is not preferable.
1 cannot uniformly cool the entire surface of the semiconductor wafer W, and there is a possibility that a temperature gradient may occur in the surface, which is not preferable. An air supply nozzle 56 is attached to each of the intake ports 53 to reach the lowermost ring-shaped support member 41 of the heat treatment boat 40, and these air supply nozzles 56 provide an even ascending airflow around the gap 60. It is configured to form. Further, the exhaust duct 51 communicates with a common duct 70 in the factory, and the exhaust duct 70 exhausts the high-temperature air exhausted from the gap 60 by the exhaust fan 52 and the air supply fan 55 while being cooled by the heat exchanger 57. The fan 71 is configured to discharge the air to the outside as shown by an arrow C in FIG. Further, shutters 58 and 59 are provided at the exhaust port 23 and the intake port 53, respectively.
Is closed so that the space 60 is sealed and the reaction vessel 30 can be efficiently heated. The exhaust port 23
The shutter 58 is formed of a heat-resistant material such as quartz, and the shutter 59 of the air supply port 53 is formed of, for example, stainless steel, fluorine-based resin, or the like.
【００１５】次に、上記熱処理装置を用いて半導体ウエ
ハＷのシリコンを酸化処理及び窒化処理する場合につい
て本実施例の成膜方法について説明する。本実施例の成
膜方法では図３で示すように熱処理を行なう。それには
まず、常圧下で加熱炉２０によって反応容器３０を加熱
してその内部温度を例えば４００℃に設定し、反応容器
３０内に熱処理ボート４０をロードして反応容器３０内
を熱処理ボート４０の底面４３Ａのフランジ部で封止
し、例えば２５枚の半導体ウエハＷ及び上下両端部のダ
ミーウエハを反応容器３０内に設置する。引き続いて反
応容器３０内の温度を二珪化モリブデンの抵抗発熱体２
１により図３ので示すように例えば１００℃／分の昇
温速度で加熱して図３に示すように内部温度を８５０℃
に設定する。この温度下でガス導入管３１から水蒸気を
供給して水蒸気圧を常圧（７６０Torr）に保持した状態
で図３ので示すように半導体ウエハＷのシリコンを１
５分間ウェット酸化して１００オングストロームのシリ
コン酸化膜（ＳｉＯｘ）を形成する。Next, a description will be given of a film forming method according to the present embodiment in a case where silicon of a semiconductor wafer W is oxidized and nitrided by using the above heat treatment apparatus. In the film forming method of this embodiment, heat treatment is performed as shown in FIG. First, the reaction vessel 30 is heated at normal pressure by the heating furnace 20 to set its internal temperature to, for example, 400 ° C., the heat treatment boat 40 is loaded into the reaction vessel 30, and the inside of the reaction vessel 30 is Sealing is performed with the flange portion of the bottom surface 43A, and for example, 25 semiconductor wafers W and dummy wafers at both upper and lower ends are placed in the reaction vessel 30. Subsequently, the temperature in the reaction vessel 30 is adjusted to the resistance heating element 2 of molybdenum disilicide.
1, the internal temperature is increased to 850 ° C. as shown in FIG.
Set to. At this temperature, water vapor is supplied from the gas introduction pipe 31 to maintain the water vapor pressure at normal pressure (760 Torr), and as shown in FIG.
A 100 Å silicon oxide film (SiO x ) is formed by wet oxidation for 5 minutes.
【００１６】その後、１００℃／分の昇温速度で図３の
で示すように加熱して内部温度を９００℃に設定し、
ガス導入管３１からアンモニアガス（ＮＨ３）を２ｌ／
分で３０分間あるいは亜酸化窒素（Ｎ２Ｏ）を５ｌ／分
で３０分間供給して図３ので示すようにシリコン酸化
膜を窒化処理してシリコン酸化膜中に窒素原子を熱拡散
させてシリコン酸化膜の表面にシリコン窒化膜（ＳｉＯ
ｘＮｙ）を形成する。更に引き続いて１００℃／分の昇
温速度で図３ので示すように加熱して内部温度を１０
００〜１１００℃に設定し、この温度下で例えば塩化水
素ガスを数％含有した酸素ガスを１０ｌ／分で３０分間
供給して図３ので示すようにシリコン窒化膜（ＳｉＯ
ｘＮｙ）に混入している水素原子を酸化処理により除去
して高集積化に適した極薄で絶縁耐性等の電気的特性に
優れた膜質のゲート酸化膜を成膜することができる。Thereafter, heating is performed at a heating rate of 100 ° C./min as shown in FIG. 3 to set the internal temperature to 900 ° C.
Ammonia gas (NH 3 ) was supplied at a rate of 2 l /
For 30 minutes or by supplying nitrous oxide (N 2 O) at 5 l / min for 30 minutes to nitride the silicon oxide film as shown in FIG. 3 and thermally diffuse nitrogen atoms into the silicon oxide film to form silicon. A silicon nitride film (SiO 2) is formed on the surface of the oxide film.
x N y) to form. Subsequently, the internal temperature is increased by 10 ° C./min to 10 ° C. as shown in FIG.
The temperature is set to 100 to 1100 ° C., and at this temperature, for example, an oxygen gas containing several percent of hydrogen chloride gas is supplied at a rate of 10 l / min for 30 minutes, and as shown in FIG.
By removing the hydrogen atoms mixed in xN y ) by oxidation treatment, a very thin gate oxide film suitable for high integration and having excellent electrical characteristics such as insulation resistance can be formed.
【００１７】その後シャッター５８、５９を開放すると
共に排気ファン５２及び給気ファン５５を駆動させ、連
通ダクト５４、複数の吸気口５３及び複数の給気ノズル
５６を介して加熱炉２０内に常温の空気を空隙部６０内
へ供給して反応容器３０の全周囲で均等な上昇気流を図
１の矢印Ｂで示すように形成すると共に、内部で昇温し
た空気を排気口２３、排気ダクト５１及び熱交換器５７
を介して排気ダクト７０へ冷却しながら排出し、排気フ
ァン７１により外部へ排出する。このように加熱炉２０
と反応容器３０間の空隙部６０全体に冷気を均等に流通
させて反応容器３０全体を均等に強制冷却して反応容器
３０内を図３ので示すよう例えば５０℃／分の降温速
度で冷却して１０００〜１１００℃から６００℃まで強
制冷却する。その後、熱処理ボート４０をアンロード
し、この熱処理ボート４０の半導体ウエハＷを未処理の
ものと交換した後、この熱処理ボート４０をロードす
る。この際６００℃の加熱炉２０が放熱して略４００℃
に降温し、次の半導体ウエハＷのロード後には上述の一
連の動作を同一条件で繰り返すことができる。After that, the shutters 58 and 59 are opened, and the exhaust fan 52 and the air supply fan 55 are driven, so that the room temperature of the heating furnace 20 is set in the heating furnace 20 through the communication duct 54, the plurality of air inlets 53 and the plurality of air supply nozzles 56. Air is supplied into the gap 60 to form a uniform rising airflow around the entire periphery of the reaction vessel 30 as shown by an arrow B in FIG. Heat exchanger 57
The air is discharged to the exhaust duct 70 while being cooled through the air outlet, and is exhausted to the outside by the exhaust fan 71. Thus, the heating furnace 20
Cooling air is evenly circulated through the entire gap 60 between the reaction vessel 30 and the reaction vessel 30 to forcibly cool the entire reaction vessel 30 to cool the inside of the reaction vessel 30 at a temperature decreasing rate of, for example, 50 ° C./min, as shown in FIG. Forcibly from 1000 to 1100 ° C to 600 ° C. Thereafter, the heat treatment boat 40 is unloaded, the semiconductor wafer W of the heat treatment boat 40 is replaced with an unprocessed one, and then the heat treatment boat 40 is loaded. At this time, the heating furnace 20 at 600 ° C. radiates heat to approximately 400 ° C.
After loading the next semiconductor wafer W, the above-described series of operations can be repeated under the same conditions.
【００１８】以上説明したように本実施例によれば、反
応容器３０から半導体ウエハＷをアンロードすることな
く、同一反応容器３０内で酸化処理、窒化処理及び脱水
素処理を連続的に行なうため、空気中のパーティクル等
の不純物がゲート酸化膜中に混入することがなく極薄且
つ緻密な膜質で絶縁耐性等の電気的特性に優れたゲート
酸化膜を短時間で成膜することができる。As described above, according to the present embodiment, the oxidizing process, the nitriding process, and the dehydrogenating process are continuously performed in the same reaction vessel 30 without unloading the semiconductor wafer W from the reaction vessel 30. , ultrathin without impurities such as particles in the air is mixed into the gate oxide film 且
A gate oxide film having a dense film quality and excellent electrical characteristics such as insulation resistance can be formed in a short time.
【００１９】また、本実施例では外部ヒータとして二珪
化モリブデンの抵抗発熱体２１を用いて１００℃／分の
昇温速度で加熱し、また冷却装置５０により空隙部６０
に冷気の上昇気流を作って５０℃／分の降温速度で強制
冷却するようにしたため、酸化処理、窒化処理及び脱水
素処理に要する時間を従来に比べて格段に短縮すること
ができ、熱処理のスループットを向上させることができ
る。尚、従来の熱処理装置の場合には、そのヒータはそ
の昇温速度が例えば５℃／分程度であり、冷却能力も十
分でなく、本実施例のような反応容器３０内の昇降温を
短時間で行なうことができず、従って、複数回に分けた
成膜操作を行なうことが難しかった。Further, in this embodiment, heating is performed at a heating rate of 100 ° C./min by using a resistance heating element 21 of molybdenum disilicide as an external heater.
As a result, the time required for oxidation treatment, nitriding treatment and dehydrogenation treatment can be shortened remarkably compared with the conventional method, so that the time required for the heat treatment can be reduced. Throughput can be improved. In the case of the conventional heat treatment apparatus, the heater has a heating rate of, for example, about 5 ° C./min, does not have a sufficient cooling capacity, and shortens the heating and cooling in the reaction vessel 30 as in this embodiment. It cannot be performed in a long time, and therefore, it is difficult to perform the film forming operation divided into a plurality of times.
【００２０】また、本実施例では半導体ウエハＷの周縁
部を熱容量の大きなリング状支持体４１で支持し、この
リング状支持体４１を介して半導体ウエハＷを加熱、冷
却するようにしたため、各リング状支持体４１で支持さ
れた半導体ウエハＷが隣合う上下の半導体ウエハＷによ
って加熱及び放熱作用が阻害されても、熱容量の大きな
リング状支持体４１によって半導体ウエハＷ周縁部の昇
温速度及び降温速度を遅延させて面内を均一に加熱、冷
却することができ、その結果、半導体ウエハＷを短時間
で均一なゲート酸化膜を成膜することができる。In the present embodiment, the periphery of the semiconductor wafer W is supported by the ring-shaped support 41 having a large heat capacity, and the semiconductor wafer W is heated and cooled via the ring-shaped support 41. Even if the semiconductor wafers W supported by the ring-shaped support 41 are obstructed by the upper and lower semiconductor wafers W from heating and radiating the heat, the ring-shaped support 41 having a large heat capacity allows the temperature rise rate of the peripheral portion of the semiconductor wafer W to be increased. It is possible to uniformly heat and cool the surface by delaying the temperature drop rate, and as a result, a uniform gate oxide film can be formed on the semiconductor wafer W in a short time.
【００２１】尚、上記実施例では酸化処理、窒化処理及
び脱水素処理をそれぞれ８５０℃、９００℃、１０００
〜１１００℃で行なう場合について説明したが、各処理
温度は必要に応じて適宜変更することができる。また、
それぞれの処理に用いられるガスも必要に応じて変更す
ることができる。In the above embodiment, the oxidation treatment, the nitridation treatment and the dehydrogenation treatment are carried out at 850 ° C., 900 ° C. and 1000 ° C., respectively.
Although the description has been given of the case where the treatment is performed at a temperature of 1100 ° C., the respective processing temperatures can be appropriately changed as needed. Also,
The gas used for each process can also be changed as needed.
【００２２】また、外部ヒータとして二珪化モリブデン
の抵抗発熱体２１を用いて昇温速度を速くしたものにつ
いて説明したが、抵抗発熱体の材料は二珪化モリブデン
に制限されるものではなく、例えば１００℃／分の昇温
速度のように短時間で反応容器３０内を昇温できるもの
であれば良い。また、冷却装置５０は上記実施例の構造
に制限されるものではなく、例えば５０℃／分の降温速
度のように短時間で降温できるものであれば良い。Further, the description has been given of the case where the heating rate is increased by using the molybdenum disilicide resistance heating element 21 as the external heater. However, the material of the resistance heating element is not limited to molybdenum disilicide. What is necessary is just to be able to raise the temperature inside the reaction vessel 30 in a short time, such as a heating rate of ° C./min. Further, the cooling device 50 is not limited to the structure of the above embodiment, but may be any device that can lower the temperature in a short time, for example, at a cooling rate of 50 ° C./min.
【００２３】また、半導体ウエハＷを支持する支持部材
は、上記実施例のリング状支持体４１に制限されるもの
ではなく、本発明における支持部材は熱容量が大きな材
料、形状として形成されたものであれば良い。Further, the support member for supporting the semiconductor wafer W is not limited to the ring-shaped support member 41 of the above embodiment, and the support member in the present invention is formed of a material and a shape having a large heat capacity. I just want it.
【００２４】[0024]
【発明の効果】本発明の請求項１に記載の発明によれ
ば、反応容器内から被処理体を取り出すことなく酸化処
理、窒化処理及び脱水素処理を連続的に行なうようにし
たため、被処理体に対して酸化処理、窒化処理及び脱水
素処理を短時間で行なうことができ、しかも空気中のパ
ーティクル等の不純物がゲート酸化膜等の酸化膜中に混
入することがなく極薄且つ緻密な膜質で絶縁耐性等の電
気的特性に優れた酸化膜を被処理体に形成することがで
きる成膜方法を提供することができる。According to the first aspect of the present invention, the oxidation , nitriding, and dehydrogenation treatments are continuously performed without removing the object from the reaction vessel . Oxidation , nitriding and dehydration of body
Can be performed hydrogen processing in a short time, moreover Pa in the air
Impurities in the oxide film such as the gate oxide film
It is possible to provide a film formation method capable of forming an oxide film having extremely thin and dense film quality and excellent electrical characteristics such as insulation resistance on a processing object without entering the film.
【図１】本発明の成膜方法に好適に用いられる熱処理装
置の一例の要部を示す断面図である。FIG. 1 is a cross-sectional view showing a main part of an example of a heat treatment apparatus suitably used in a film forming method of the present invention.
【図２】図１に示す熱処理装置の熱処理ボートの半導体
ウエハの支持部材を拡大して示す断面図である。2 is an enlarged sectional view showing a support member for a semiconductor wafer of a heat treatment boat of the heat treatment apparatus shown in FIG.
【図３】本発明の成膜方法に好ましい一実施例を示す処
理温度の経過を示す図である。FIG. 3 is a diagram showing the progress of a processing temperature showing one preferred embodiment of the film forming method of the present invention.
２０ 加熱炉 ２１ 抵抗発熱体（外部ヒータ、二珪化モリブデン） ３０ 反応容器 ４０ 熱処理ボート（保持具） ５０ 冷却装置 ６０ 空隙部 Reference Signs List 20 heating furnace 21 resistance heating element (external heater, molybdenum disilicide) 30 reaction vessel 40 heat treatment boat (holding tool) 50 cooling device 60 void
フロントページの続き (72)発明者 池川 寛晄 神奈川県津久井郡城山町町屋１丁目２番 41号 東京エレクトロン東北株式会社 相模事業所内 (56)参考文献 特開 昭54−163679（ＪＰ，Ａ) 特開 平３−257828（ＪＰ，Ａ) 特開 昭51−122180（ＪＰ，Ａ) 特開 平２−310924（ＪＰ，Ａ) (58)調査した分野(Int.Cl.7，ＤＢ名) H01L 21/318 Continuation of the front page (72) Inventor Hiroko Ikegawa 1-241 Machiya, Shiroyama-cho, Tsukui-gun, Kanagawa Prefecture Inside the Sagami Plant of Tokyo Electron Tohoku Co., Ltd. (56) References JP-A-54-163679 (JP, A) JP-A-3-257828 (JP, A) JP-A-51-122180 (JP, A) JP-A-2-310924 (JP, A) (58) Fields investigated (Int. Cl. 7 , DB name) H01L 21 / 318
Claims (1)
理温度まで昇温させた反応容器内へ所定の酸化処理用ガ
スを供給する工程と、上記反応容器内で保持具により保
持された複数の被処理体の表面を酸化処理用ガスにより
酸化させて酸化膜を形成する工程と、上記反応容器内の
酸化処理用ガスを所定の窒化処理用ガスで置換する工程
と、上記外部ヒータにより上記反応容器内を所定の窒化
処理温度まで加熱して上記酸化膜に窒化処理を施す工程
と、上記反応容器内の窒化処理用ガスを塩化水素ガスを
含む酸素ガスと置換する工程と、上記外部ヒータにより
上記反応容器内を上記窒化処理温度より高い温度まで加
熱して窒化処理により上記酸化膜に混入した水素原子を
除去する脱水素処理を施す工程とを備え、上記反応容器
内からその外部へ上記各被処理体を取り出すことなく上
記各工程を連続して行うことを特徴とする成膜方法。1. A method for heating a semiconductor device by a predetermined oxidation treatment by heating with an external heater.
A step of supplying the physical temperature to warm to cause the reaction vessel to a predetermined oxidation gas, and a surface of the plurality of the object held by the holder in the reaction vessel was oxidized by oxidizing processing gas forming an oxide film, in the reaction vessel
A step of replacing the oxidizing gas with a predetermined nitriding gas
And a step of performing a nitriding treatment on the oxide film is heated by the external heater the reaction vessel to a predetermined nitriding temperature
And the nitriding gas in the reaction vessel is replaced with hydrogen chloride gas.
Replacing with oxygen gas containing, and the above-mentioned external heater
The inside of the reaction vessel is heated to a temperature higher than the nitriding temperature.
Hydrogen atoms mixed into the above oxide film by heating and nitriding
Performing a dehydrogenation treatment for removing the reaction vessel,
Without removing each of the above objects from inside to outside
A film forming method, wherein each step is performed continuously .
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP05189395A JP3081886B2 (en) | 1993-06-30 | 1993-06-30 | Film formation method |
| KR1019940001926A KR950001882A (en) | 1993-06-30 | 1994-02-02 | Heat treatment method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP05189395A JP3081886B2 (en) | 1993-06-30 | 1993-06-30 | Film formation method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0786264A JPH0786264A (en) | 1995-03-31 |
| JP3081886B2 true JP3081886B2 (en) | 2000-08-28 |
Family
ID=16240586
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP05189395A Expired - Fee Related JP3081886B2 (en) | 1993-06-30 | 1993-06-30 | Film formation method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3081886B2 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TW577129B (en) | 1997-03-05 | 2004-02-21 | Hitachi Ltd | Method for fabricating semiconductor integrated circuit device |
| JP3472482B2 (en) * | 1998-06-30 | 2003-12-02 | 富士通株式会社 | Semiconductor device manufacturing method and manufacturing apparatus |
| JP4606600B2 (en) * | 2001-01-09 | 2011-01-05 | 東京エレクトロン株式会社 | Process air supply apparatus and method |
-
1993
- 1993-06-30 JP JP05189395A patent/JP3081886B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0786264A (en) | 1995-03-31 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP3504784B2 (en) | Heat treatment method | |
| JP3421660B2 (en) | Heat treatment apparatus and method | |
| JP3474258B2 (en) | Heat treatment apparatus and heat treatment method | |
| JP3578402B2 (en) | Wafer processing system and wafer processing method | |
| JP2002075890A (en) | Heat treatment system and control method of decreasing temperature rate thereof | |
| JP3910151B2 (en) | Heat treatment method and heat treatment apparatus | |
| JP2003133284A (en) | Batch type vacuum treatment equipment | |
| US5500388A (en) | Heat treatment process for wafers | |
| US20030221623A1 (en) | Fabricating a semiconductor device | |
| JP3081886B2 (en) | Film formation method | |
| KR100248566B1 (en) | Heat treating method | |
| JP3207402B2 (en) | Semiconductor heat treatment apparatus and semiconductor substrate heat treatment method | |
| JP4553227B2 (en) | Heat treatment method | |
| JP4218360B2 (en) | Heat treatment apparatus and heat treatment method | |
| JPH11260744A (en) | Heat treating furnace | |
| JPH07153695A (en) | Method of forming film | |
| JP2004311648A (en) | Substrate processing equipment | |
| JP2001156011A (en) | Heat treatment equipment for semiconductor wafer | |
| JP3173698B2 (en) | Heat treatment method and apparatus | |
| JP3340147B2 (en) | Processing equipment | |
| JP3464505B2 (en) | Heat treatment method | |
| JP3118741B2 (en) | Heat treatment method and heat treatment apparatus | |
| JP2693465B2 (en) | Semiconductor wafer processing equipment | |
| JPH1167782A (en) | Heat treatment | |
| JPH11111709A (en) | Heat treatment |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| LAPS | Cancellation because of no payment of annual fees |