JPS63208691A - Operation of inverter-driven oil-free screw vacuum pump - Google Patents
Operation of inverter-driven oil-free screw vacuum pumpInfo
- Publication number
- JPS63208691A JPS63208691A JP4338187A JP4338187A JPS63208691A JP S63208691 A JPS63208691 A JP S63208691A JP 4338187 A JP4338187 A JP 4338187A JP 4338187 A JP4338187 A JP 4338187A JP S63208691 A JPS63208691 A JP S63208691A
- Authority
- JP
- Japan
- Prior art keywords
- pressure
- reaction tank
- vacuum pump
- inverter
- rotation speed
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000000034 method Methods 0.000 claims abstract description 27
- 238000006243 chemical reaction Methods 0.000 claims abstract description 25
- 230000003247 decreasing effect Effects 0.000 claims abstract description 3
- 238000004519 manufacturing process Methods 0.000 claims description 7
- 239000004065 semiconductor Substances 0.000 claims description 5
- 230000006835 compression Effects 0.000 claims description 2
- 238000007906 compression Methods 0.000 claims description 2
- 238000010521 absorption reaction Methods 0.000 claims 1
- 238000007789 sealing Methods 0.000 claims 1
- 230000006837 decompression Effects 0.000 abstract 1
- 235000012431 wafers Nutrition 0.000 description 5
- 230000001105 regulatory effect Effects 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 230000001276 controlling effect Effects 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000000428 dust Substances 0.000 description 2
- 238000011017 operating method Methods 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 239000006227 byproduct Substances 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000003584 silencer Effects 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Applications Or Details Of Rotary Compressors (AREA)
- Chemical Vapour Deposition (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、スクリュ式真空ポンプの運転方法に係り、特
に大気圧から１０””Ｔｏｒｒレベルの低・中真空領域
に好適な作動室に油の混入のないスクリュ式真空ポンプ
を半導体製造ラインのＣＶＤ装置の反応槽内圧力を変化
させるために用いる際の運転方法に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of operating a screw type vacuum pump, and in particular, the present invention relates to a method of operating a screw type vacuum pump, and in particular, the present invention relates to a method for operating a screw type vacuum pump, and in particular, the present invention relates to a method for operating a screw type vacuum pump, and in particular, the present invention relates to a method for operating a screw type vacuum pump. The present invention relates to an operating method when using a screw-type vacuum pump without contamination to change the pressure inside a reaction tank of a CVD device in a semiconductor manufacturing line.
従来の半導体製造ラインの一例を第５図に示す。 An example of a conventional semiconductor manufacturing line is shown in FIG.
この従来例はＣＶＤ装置のラインの一例で、■の反応槽
、２のスロー排気弁、３のメイン弁、４の自動圧力調整
弁・、５のルーツタイプのメカニカルブースタポンプ、
６の油回転ポンプより構成されており、第５図矢印の方
向よりプロセスガスが１の反応槽内に導入される。This conventional example is an example of a CVD equipment line, which includes a reaction tank (2), a slow exhaust valve (2), a main valve (3), an automatic pressure adjustment valve (4), a roots-type mechanical booster pump (5),
The process gas is introduced into the reaction tank 1 from the direction of the arrow in FIG. 5.
プロセスは以下の手順で進行していく。The process proceeds in the following steps.
■ 反応槽内に被加工物であるウェハを設置する。■ Place the wafer, which is the workpiece, in the reaction tank.
■ 初めに６の油回転ポンプＲＰを運転し、次に排気系
全体がある圧力に低下したら５のメカニカルブースタポ
ンプＭＢＰを運転し、反応槽１内をある圧力以下（ベー
ス圧力）に減圧する。(1) First, the oil rotary pump RP (No. 6) is operated, and then, when the pressure of the entire exhaust system drops to a certain level, the mechanical booster pump MBP (No. 5) is operated to reduce the pressure inside the reaction tank 1 to below a certain pressure (base pressure).
この■の過程でいきなり３のメイン弁を開くのではなく
、まず、よりサイズの小さな弁すなわち２のスロー排気
弁を開くことにより、１の反応槽内の圧力を徐々に低く
する。その理由は、急激に反応槽１内を低くすることに
より、反応槽１内にゴミ （各種の副生成物・５ｉ０２
等）をまい上らせウェハー」−に付着することを防ぐた
めである。In the process (2), instead of suddenly opening the main valve 3, first open a smaller valve, that is, the slow exhaust valve 2, to gradually lower the pressure inside the reaction tank 1. The reason for this is that by suddenly lowering the inside of the reaction tank 1, dirt (various by-products, 5i02
This is to prevent the wafer from sticking to the wafer.
そして、反応槽１内をある圧力Ｐｃｒ以下になったとこ
ろで、３のメイン弁が開くことになる。Then, when the pressure inside the reaction tank 1 falls below a certain pressure Pcr, the main valve 3 opens.
■ 次に、さらに７の弁を開き、必要量のプロセスガス
８を導入し、ウェハーに所定の薄膜を生成する。(2) Next, valve 7 is further opened, and the required amount of process gas 8 is introduced to form a predetermined thin film on the wafer.
また、この■の過程では、プロセスガス導入中の１の反
応槽内の圧力を一定の圧力を調節する必要がある。この
圧力調整は、４の自動圧力調整弁ＡＰＣが行っている。Further, in the process (2), it is necessary to adjust the pressure in the first reaction tank to a constant pressure while the process gas is being introduced. This pressure adjustment is performed by automatic pressure regulating valve APC 4.
以］二、述べたように、このような−プロセス中にスロ
ー排気弁、メイン弁および自動圧力調整弁の３個の弁を
有効的に作動させる複雑なコントロールが必要となる。Second, as mentioned above, complex controls are required to effectively operate three valves: the slow exhaust valve, the main valve, and the automatic pressure regulating valve during such a process.
また、これらの弁の合計価格は非常に高いものとなって
いる。Additionally, the total price of these valves is very high.
上記第５図の如き従来技術は−プロセス中で３個の精密
で高価な弁をプロセスに合わせてコントロールする必要
があり、それだけ故障も多く、信頼性の低いものであっ
た。The prior art as shown in FIG. 5 above requires three precise and expensive valves to be controlled in accordance with the process, which causes many failures and low reliability.
また、圧力レベルの違いにより、メカニカルブースタポ
ンプＭＢＰ、油回転ポンプＲＰの二種類のポンプを必要
とした。また、これらポンプの起動・停止のためのセン
サーやコントローラ（図示せず）が必要であった。Furthermore, due to differences in pressure levels, two types of pumps were required: a mechanical booster pump MBP and an oil rotary pump RP. Additionally, sensors and controllers (not shown) were required to start and stop these pumps.
本発明は、これら三つの弁をなくし装置全体を簡略化す
ることを目的とする。The present invention aims to eliminate these three valves and simplify the entire device.
上記目的は、メカニカルブースタポンプＭＢＰ、油回転
ポンプＲＰを低回転速度でも圧力がでる高性能タイプの
スクリュ真空ポンプに置きかえ、尚かつ、このポンプを
インバータにより可変速駆動し、ポンプの圧力を制御す
ることにより達成される。The above purpose is to replace the mechanical booster pump MBP and oil rotary pump RP with high-performance screw vacuum pumps that can generate pressure even at low rotational speeds, and to control the pump pressure by driving these pumps at variable speeds with an inverter. This is achieved by
ここにいう高性能タイプのスクリュ真空ポンプは、すで
に出願人が開発し出願しているスクリュ真空ポンプ（特
開昭６１−１５２９９０号、特開昭６０−２１６０８９
号）を指すが、詳しくは。The high-performance type screw vacuum pump mentioned here is the screw vacuum pump that the applicant has already developed and applied for (Japanese Patent Application Laid-Open No. 61-152990, Japanese Patent Application Laid-open No. 60-216089).
(No.), but for more details.
スクリュロータには、一対ロータの術数が、雄ロータの
それが、雌ロータのそれの一枚少くなっているもので構
成し、その溝部に沿って少くとも一対の作ｉｌ！ｊノ室
を、１油記両ロータとケーシングとによって形成し、こ
の一対の作動室の−っは、圧縮・吐水作用を有し、残り
の作動室は吸入・移送作用を有するロータを採用したス
クリュ真空ポンプをいう（特開昭６１−４５２９９０号
参照）。そして、まず反応槽内の圧力を減圧する際には
ある圧力Ｐｃｒになるまでは所定の回転速度より小さな
回転速度で減圧し、ある圧力Ｐｃｒになった後は所定の
回転速度より大きな回転速度で減圧し、次に減圧後にプ
ロセスガスを導入する際にはプロセスガス流量の変化に
応じて回転速度を増減して反応槽内の圧力を一定に保つ
。The screw rotor is composed of a pair of rotors, the number of which is one less than that of the male rotor and that of the female rotor, and at least one pair of rotors are formed along the groove. The two working chambers are formed by a rotor and a casing, and one of the working chambers has a compression and water discharging function, and the remaining working chambers have a rotor that has a suction and transfer function. Refers to a screw vacuum pump (see JP-A-61-452990). First, when reducing the pressure inside the reaction tank, the pressure is reduced at a rotation speed lower than the predetermined rotation speed until a certain pressure Pcr is reached, and after the pressure reaches a certain pressure Pcr, the rotation speed is higher than the predetermined rotation speed. When the pressure is reduced and then a process gas is introduced after the pressure reduction, the rotational speed is increased or decreased in accordance with changes in the flow rate of the process gas to keep the pressure inside the reaction tank constant.
反応槽内の圧力を減圧する際に、ある圧力Ｐｃｒになる
までは所定の回転速度より小さな回転速度で減圧し、あ
る圧力Ｐｃｒになった後は所定の回転速度より大きな回
転速度で減圧することにより、従来のスロー排気弁とメ
イン弁の働きができ、これらの弁を省くことができる。When reducing the pressure in the reaction tank, the pressure is reduced at a rotational speed lower than a predetermined rotational speed until a certain pressure Pcr is reached, and after the pressure reaches a certain pressure Pcr, the pressure is reduced at a rotational speed higher than the predetermined rotational speed. This enables the function of the conventional slow exhaust valve and main valve, and these valves can be omitted.
また減圧後にプロセスガスを導入する際に、プロセスガ
ス流ｂｔの変化に応じて回転速度を増減して反応槽内の
圧力を一定に保つことにより、圧力調整弁（Ａ Ｐ Ｃ
） を省くことができる。In addition, when introducing process gas after pressure reduction, the pressure regulating valve (A P C
) can be omitted.
以下、本発明の一実施例を第１図〜第４図に示す。 An embodiment of the present invention is shown in FIGS. 1 to 4 below.
まず、第４図でスクリュ真空ポンプ外観を示す。First, Fig. 4 shows the external appearance of the screw vacuum pump.
１１のポンプ本体にスクリュが内蔵され、１２のギヤケ
ース内蔵の増速ギヤで増減速がされる。また、１３は起
動盤で各種押しボタンが設置され、起動、停止、及び、
回転速の調整をしている。A screw is built into the pump body 11, and speeding up and deceleration is performed by a speed increasing gear built into the gear case 12. In addition, 13 is a starting board with various push buttons installed, starting, stopping, and
Adjusting the rotation speed.
１４はインバータである。プロセスガスは、１５の吸気
管より吸引され、排気管を兼ねている１６のサイレンサ
を介し、さらに、下流へと導かれる。14 is an inverter. The process gas is sucked in through 15 intake pipes, passes through 16 silencers that also serve as exhaust pipes, and is guided further downstream.
これらの部品は、キャスタ１７付のコモンベース１８上
に合理的に配置されている。These parts are rationally arranged on a common base 18 with casters 17.
第１図は、このスクリュ真空ポンプを使用した場合のＣ
ＶＤＩＵ置ライ装の一例を示す。第２図及び第３図はス
クリュ真空ポンプの回転速度をあられす。Figure 1 shows C when using this screw vacuum pump.
An example of a VDIU device is shown. Figures 2 and 3 show the rotational speed of the screw vacuum pump.
この場合のプロセスは以下のように進行する。The process in this case proceeds as follows.
■ まず反応槽１内のベース圧まで、２１のオイルフリ
ースクリュ真空ポンプＳＰを低回転速度Ｎ１で運転し徐
々に減圧させる。そして、ゴミ（生成物）かまい上がら
ない程度の圧力Ｐｃｒまでに圧力が下がったら、回転速
度を徐々にＮ２にまで上げていく。(2) First, the oil-free screw vacuum pump SP 21 is operated at a low rotational speed N1 to gradually reduce the pressure in the reaction tank 1 to the base pressure. Then, when the pressure drops to a level Pcr that does not allow dust (products) to rise, the rotational speed is gradually increased to N2.
この■の過程を第２図によってさらに詳しく説明する。This process (2) will be explained in more detail with reference to FIG.
図は横軸に時間、縦軸に圧力をとり、スクリュ真空ポン
プの回転速度による、反応槽内の圧力変化を示す。反応
槽内の圧力変化は、ある圧力Ｐｃｒまでは検尺に下げる
必要がある。その理由は、Ｐｃｒよりも高い圧力で急速
に減圧すると、反応槽内のゴミ、生成物をまい上げる力
となり、被加工物（ｉｃウェハー）の歩留り等に多大な
影響を及ぼす。しかし、Ｐｃｒよりも低い圧力では、そ
のようなまい上らせる力は発生しないので、生産能率の
観点から減圧する速さは早ければ早いほどよい。そして
、従来は既に述べたように減圧する速さの３１１整を、
配管に口径小のスロー排気弁、口径大のメイン弁を設け
て行っていた。ところが本実施例ならば、圧力計Ｐによ
るコントロールによりある圧力Ｐｃｒよりも高い圧力で
は１回転速度Ｎ１の低いところで運転し、ある圧力Ｐｃ
ｒよりも低いところでは、Ｎ２を高くすることにより対
処が可能となる。The figure shows time on the horizontal axis and pressure on the vertical axis, showing the change in pressure inside the reaction tank depending on the rotation speed of the screw vacuum pump. The pressure change inside the reaction tank must be reduced to a certain pressure Pcr. The reason for this is that if the pressure is rapidly reduced to a pressure higher than Pcr, it will cause a force to blow up dust and products in the reaction tank, which will have a great effect on the yield of the workpieces (IC wafers). However, such an upward force is not generated at a pressure lower than Pcr, so from the viewpoint of production efficiency, the faster the pressure is reduced, the better. Conventionally, as already mentioned, the speed of depressurization is 311,
A small-diameter slow exhaust valve and a large-diameter main valve were installed in the piping. However, in this embodiment, when the pressure is higher than a certain pressure Pcr by controlling the pressure gauge P, the operation is performed at a low 1 rotational speed N1, and when the certain pressure Pc
If it is lower than r, it can be dealt with by increasing N2.
■ また、プロセスガスの流量の変化に対し、反応槽１
内圧力を調整するのも、スクリュ真空ポンプＳ Ｉ）の
回転速度をインバータにより微調整しながら行うことが
できる。■ Also, in response to changes in the flow rate of process gas,
The internal pressure can also be adjusted while finely adjusting the rotational speed of the screw vacuum pump SI) using an inverter.
この■の過程を第３図によってさらに詳しく説明する。This process (2) will be explained in more detail with reference to FIG.
１図は１回転速度Ｎと圧力Ｐの関係を示す。Figure 1 shows the relationship between one rotational speed N and pressure P.
回転速度Ｎを高くすると圧力Ｐは低くなる。この関係は
、ガス流量を変化させても基本的には変らない。したが
って、プロセスガス流量Ｑが変化しても、圧力計Ｐから
発する信号によって回転速度Ｎを変化させることにより
、反応槽内の圧力Ｐをある一定の圧力に保持できること
になる。As the rotational speed N increases, the pressure P decreases. This relationship basically does not change even if the gas flow rate is changed. Therefore, even if the process gas flow rate Q changes, by changing the rotational speed N based on the signal issued from the pressure gauge P, the pressure P in the reaction tank can be maintained at a certain constant pressure.
本発明によれば、反応槽内の圧力をスクリュ真空ポンプ
の回転速度により調節することができるので、スロー排
気弁、メイン弁、圧力調整弁（ＡＰＣ）、及びこれらを
コントロールする複雑なシステムを省くことができる。According to the present invention, the pressure inside the reaction tank can be adjusted by the rotational speed of the screw vacuum pump, thereby eliminating the need for a slow exhaust valve, a main valve, a pressure control valve (APC), and a complicated system for controlling these. be able to.
また、故障しやすい自動圧力調節弁（ＡＰＣ）を省くこ
とにより、半導体製造装置の信頼性を向−ヒすることが
でき、配管が大幅に簡素化されるので、半導体製造ライ
ンが存在するスクリュルームの省スペースにもなる。In addition, by eliminating automatic pressure control valves (APCs) that are prone to failure, the reliability of semiconductor manufacturing equipment can be improved, and piping can be greatly simplified, allowing screw rooms where semiconductor manufacturing lines are located. It also saves space.
第１図は本発明の運転方法を使用した場合のＣＶＤ装置
製造ラインを示す図、第２図及び第３図は第４図のスク
リュ真空ポンプの回転速度Ｎの増減を示す図、第４図は
本発明に使用されるスクリュ真空ポンプの外観を示す全
体図、第５図は従来のＣＶＤ装置′ＩＡ造のラインを示
す図である。
１・・・反応槽、 ２・・・スロー排気弁、
３・・メイン弁、 ４・・・自動圧力調整弁、５
・・メカニカルブースタポンプ、
６・・油回転ポンプ、 ７・・・弁。
１１・・・ポンプ本体、 １２・・ギヤケース、１
３・・・起動盤、 １４・・インバータ、１５
・・・吸気管、 １６・・サイレンサ。
１７・・・キャスタ、 １８・・・コモンベース
、２１・・・オイルフリースクリュ真空ポンプ。FIG. 1 is a diagram showing a CVD device manufacturing line when the operating method of the present invention is used, FIGS. 2 and 3 are diagrams showing increases and decreases in the rotational speed N of the screw vacuum pump in FIG. 4, and FIG. 5 is an overall view showing the external appearance of the screw vacuum pump used in the present invention, and FIG. 5 is a view showing the line of conventional CVD apparatus 'IA construction. 1... Reaction tank, 2... Slow exhaust valve,
3... Main valve, 4... Automatic pressure regulating valve, 5
...Mechanical booster pump, 6.Oil rotary pump, 7.Valve. 11...Pump body, 12...Gear case, 1
3... Starting board, 14... Inverter, 15
...Intake pipe, 16...Silencer. 17...Casters, 18...Common base, 21...Oil-free screw vacuum pump.
Claims (1)
るポンプケーシングと、両端部が軸支され同期して回転
するように前記ポンプケーシング内に配置された互いに
噛み合う一対のロータと、それぞれのロータ軸支部に設
けられた軸封装置とを備えてなり、前記一対のロータの
歯数が雄ロータのそれが、雌ロータのそれの一枚少なく
なっているもので構成し、その溝部に沿って少くとも一
対の作動室の一つは、圧縮・吐出作用を有し、残りの作
動室は吸収・移動作用を有するスクリュポンプを利用し
て半導体製造ラインのＣＶＤ装置の反応槽内圧力を変化
させる場合に、 インバータを使用して該スクリュポンプを可変速で運転
し、まず反応槽内の圧力を減少する際にはある圧力Ｐｃ
ｒになるまでは所定の回転速度より小さな回転速度で減
圧し、ある圧力Ｐｃｒになった後は所定の回転速度より
大きな回転速度で減圧し、次に、減圧後にプロセスガス
を導入する際にはプロセスガス流量の変化に応じて回転
速度を増減して反応槽内の圧力を一定に保つことを特徴
とするインバータ駆動オイルフリースクリュ真空ポンプ
の運転方法。(1) A pump casing in which a suction port and a discharge port are formed, a pair of rotors that mesh with each other and are disposed within the pump casing so that both ends are pivotally supported and rotate synchronously, and each rotor and a shaft sealing device provided on the shaft support, and the pair of rotors have one tooth less than that of the male rotor than that of the female rotor, and the number of teeth of the pair of rotors is one less than that of the female rotor, and At least one of the pair of working chambers has a compression/discharge function, and the remaining working chambers use a screw pump to have an absorption/transfer function to change the pressure inside a reaction tank of a CVD device in a semiconductor manufacturing line. In this case, the screw pump is operated at variable speed using an inverter, and the pressure in the reaction tank is first reduced to a certain pressure Pc.
The pressure is reduced at a rotation speed lower than the predetermined rotation speed until the pressure reaches r, and after reaching a certain pressure Pcr, the pressure is reduced at a rotation speed higher than the predetermined rotation speed. Next, when introducing the process gas after pressure reduction, A method of operating an inverter-driven oil-free screw vacuum pump characterized by increasing or decreasing the rotational speed in response to changes in process gas flow rate to maintain constant pressure within a reaction tank.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4338187A JPS63208691A (en) | 1987-02-26 | 1987-02-26 | Operation of inverter-driven oil-free screw vacuum pump |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4338187A JPS63208691A (en) | 1987-02-26 | 1987-02-26 | Operation of inverter-driven oil-free screw vacuum pump |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS63208691A true JPS63208691A (en) | 1988-08-30 |
Family
ID=12662237
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4338187A Pending JPS63208691A (en) | 1987-02-26 | 1987-02-26 | Operation of inverter-driven oil-free screw vacuum pump |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS63208691A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09209949A (en) * | 1996-02-02 | 1997-08-12 | Hitachi Ltd | Screw compressor, and control method thereof |
| CN105649986A (en) * | 2014-11-10 | 2016-06-08 | 中国科学院沈阳科学仪器股份有限公司 | Anti-impact structure used for multi-level vacuum pump and multi-stage vacuum pump comprising same |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS59142621A (en) * | 1983-02-02 | 1984-08-15 | Canon Inc | Pressure adjusting method of vacuum device |
-
1987
- 1987-02-26 JP JP4338187A patent/JPS63208691A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS59142621A (en) * | 1983-02-02 | 1984-08-15 | Canon Inc | Pressure adjusting method of vacuum device |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09209949A (en) * | 1996-02-02 | 1997-08-12 | Hitachi Ltd | Screw compressor, and control method thereof |
| CN105649986A (en) * | 2014-11-10 | 2016-06-08 | 中国科学院沈阳科学仪器股份有限公司 | Anti-impact structure used for multi-level vacuum pump and multi-stage vacuum pump comprising same |
| CN105649986B (en) * | 2014-11-10 | 2018-07-20 | 中国科学院沈阳科学仪器股份有限公司 | Impact-proof structure for multistage vacuum pump and the multistage vacuum pump with the structure |
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