EP0338113A1 - Method for the adaptation of a 2-stage cryogenic pump to a specific gas - Google Patents

Method for the adaptation of a 2-stage cryogenic pump to a specific gas Download PDF

Info

Publication number
EP0338113A1
EP0338113A1 EP88106497A EP88106497A EP0338113A1 EP 0338113 A1 EP0338113 A1 EP 0338113A1 EP 88106497 A EP88106497 A EP 88106497A EP 88106497 A EP88106497 A EP 88106497A EP 0338113 A1 EP0338113 A1 EP 0338113A1
Authority
EP
European Patent Office
Prior art keywords
stage
cryopump
gas
temperature
cold
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.)
Granted
Application number
EP88106497A
Other languages
German (de)
French (fr)
Other versions
EP0338113B1 (en
Inventor
Hans-Ulrich Dr. Häfner
Hans-Joachim Dr. Forth
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Balzers und Leybold Deutschland Holding AG
Original Assignee
Leybold AG
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Leybold AG filed Critical Leybold AG
Priority to AT88106497T priority Critical patent/ATE72301T1/en
Priority to EP88106497A priority patent/EP0338113B1/en
Priority to DE8888106497T priority patent/DE3868264D1/en
Priority to US07/338,606 priority patent/US4953359A/en
Priority to JP1097712A priority patent/JP2668261B2/en
Publication of EP0338113A1 publication Critical patent/EP0338113A1/en
Application granted granted Critical
Publication of EP0338113B1 publication Critical patent/EP0338113B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B37/00—Pumps having pertinent characteristics not provided for in, or of interest apart from, groups F04B25/00 - F04B35/00
    • F04B37/06—Pumps having pertinent characteristics not provided for in, or of interest apart from, groups F04B25/00 - F04B35/00 for evacuating by thermal means
    • F04B37/08—Pumps having pertinent characteristics not provided for in, or of interest apart from, groups F04B25/00 - F04B35/00 for evacuating by thermal means by condensing or freezing, e.g. cryogenic pumps
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S417/00—Pumps
    • Y10S417/901—Cryogenic pumps

Definitions

  • the invention relates to a method for adapting a two-stage refrigerator cryopump to a specific gas; the cryopump has a first cooling stage, to which pumping surfaces are attached and which is equipped with a heating device; in addition, the cryopump has a second cooling stage, to which the pumping surfaces are attached and which takes on a temperature between approx. 10 and 20 K during operation. Furthermore, the invention relates to cryopumps suitable for carrying out this method.
  • the first stage can vary depending on the pump size, type, process and external load in a wide range from approx. 50 K to 150 k.
  • Gases the vapor pressure curves of which lie between the previously mentioned condensable first gases and the condensable second gases, can therefore condense at sufficiently high process pressures at sufficiently cold points in the first stage. If you subsequently want to pump down to lower pressures, this is sometimes not possible because the first stage is not cold enough for this.
  • the gas previously frozen on the first stage slowly migrates over to the second stage at a pressure between 10 ⁇ 3 and 10 utilise mbar. H. the pressure remains at an intermediate pressure; the pump no longer seems to be pumping.
  • Another disadvantage of the passive load is that it is always present and thus extends the cold running time of the cryopump.
  • the present invention is based on the object of specifying a method of the type mentioned at the outset and a cryopump for carrying out this method, which enable optimum pump behavior in the case of gases with different vapor pressures and in which the cold driving time is not impaired.
  • this object is achieved in that the heating device of the first stage is controlled in such a way that the coldest point of the first cold stage or its pumping surfaces assumes a temperature which is approximately 5 to 10 K higher than the temperature at which the vapor pressure of the respective gas is just equal to the highest occurring process pressure.
  • the temperature of the first stage can also be kept constant regardless of varying external loads, since less heating power is used when the external load increases.
  • the temperature control according to the invention can be used to observe the load condition of the pump. The higher the load, the less often the heater switches on. Generally speaking, the state of the pump is also stabilized against changing external loads by the actively controlled heating load.
  • the cryopumps 1 with the housing 2 each shown in the figures each comprise the only partially illustrated two-stage refrigerator cold head 3, the cooling stages of which are designated 4 (first stage) and 5 (second stage).
  • the cup-shaped pump surface or shield 6 is fastened in a heat-conducting manner, so that it encloses the interior 8 of the pump together with the baffle 7 carried and cooled by the shield 6.
  • the pumping surfaces 10 of the second stage which are connected to the second cold head stage with good thermal conductivity.
  • the inlet opening 9 of the pump equipped with the baffle 7 is preceded by a valve 11 only shown in FIG. It comprises a fixed disk 12 and a rotatable disk 13, each of which has essentially radial slot openings. The valve can be actuated by rotating the disk 13.
  • the housing 2 of the cryopump 1 has a connecting piece 14 at approximately the level of the stage 4 of the first refrigerator stage, which supports a monitoring device denoted by 15.
  • a monitoring device denoted by 15.
  • this device there is a circuit for supplying heating devices 16 and 17 with which the cold heads 4 and 5 of the two-stage cold head 3 are equipped.
  • a vacuum-tight bushing 23 is provided for the connecting lines 18 and 19 between the supply unit 15 and the heating devices 16, 17 in the region of flanges 21, 22 on the supply unit 15 and on the connecting piece 14.
  • the cryopump there is also a temperature sensor 24, which is provided at the cold stage 4 and whose measuring line 26 also leads to the monitoring device 15.
  • a supply unit 27, shown as a block, is connected to this monitoring device 15.
  • the monitoring device In addition to its function as overtemperature protection when regenerating with electric heaters, the monitoring device also serves 15 to ensure the setting of the desired temperature of the cold stage 4 and the pumping surfaces or shields 6, 7 carried by it.
  • the temperature of the cold stage 4 is measured using the sensor 24.
  • This measured value is fed to the monitoring device 15. There, this measured value is compared with a target value, which depends on the gas to be pumped. If the temperature of the cold head is below this target value, the heating device 16 switches on until the target temperature has been reached, and then off again, etc.
  • the vapor pressure curves of various gases are shown in FIG. Since, according to the teaching of the invention, the heating device is to be controlled in such a way that the coldest point of the first cooling stage or its pumping surfaces has a temperature which is 5 to 10 K higher than the vapor pressure temperature of the gas to be pumped which corresponds to the highest process pressure the target temperature to be set can be read from the family of curves shown.
  • the process gases usually occur (e.g. in sputter processes) initially with a pressure of a few 10 ⁇ 3 mbar.
  • the 10 ⁇ 3 mbar line intersects the vapor pressure curves shown.
  • the temperature to be set is therefore a value that is 5 to 10 K to the right of the intersection of the 10 ⁇ 3 mbar line with the associated vapor pressure curve.
  • the temperature of the first stage or its pumping surfaces to a value of about 55 to 60 K. Is preferably NH 3 to be pumped, then a temperature should be selected which is about 130 to 135 K. With such a choice of temperature, it is ensured that the gas considered in each case does not accumulate on the first pump stage, but is pumped directly by the pump surfaces of the second stage. Rearrangements that interfere with a pressure reduction during later pumping to ⁇ 10 ⁇ 3 mbar no longer occur.
  • both pump stages are equipped with a heating device 16, 17.
  • they serve to regenerate the pump surfaces of both stages by heating these pump surfaces to room temperature.
  • the first stage is counter-heated by heat radiation onto a section of the shield 6.
  • the housing 2 of the cryopump 1 is equipped with a further connecting piece 31.
  • a radiation source 32 which, for. B. can be a high-energy light source or the like.
  • suitable optics 35 the holder of which simultaneously forms the vacuum-tight seal of the interior 8 of the housing 2, the radiation emanating from the radiation source is concentrated on the outer surface of the pump surface 6, which is expediently blackened at this point.
  • a temperature sensor 24 is again provided on the cold stage 4, which supplies its measured values to the control unit 27. This is where the comparison with the set target temperature value takes place. Accordingly, the radiation source 32 is switched on and off or its luminosity is regulated. It is useful with this solution that live lines do not have to be laid inside the cryopump.
  • FIG. 4 shows an embodiment in which the cooling stage 4 is equipped with a heat exchanger, here in the form of a pipe coil 41. Through this coil, 4 warm gas, for. B. from the helium circuit of the refrigerator. An external heat exchanger 42 with an electric heater 43, which is supplied by the control unit 15, serves to heat the gas. This heat exchanger is located together with the valve 44 in the gas supply line.
  • This arrangement enables two methods of adjusting the temperature of the cold stage 4. Either the gas flow can be controlled if the valve 44 is designed as a metering control valve. Another option is to get one supply a constant gas flow and heat the temperature of the gas in a controlled manner with the help of the heat exchanger.
  • a component 51 is fastened to the cold stage 4 and has a downwardly directed threaded bore 52.
  • a rod 53 can be screwed into this threaded bore 52, the free end of which has room temperature or is heated.
  • the screw thread forms a heat exchange surface, the size of which can be regulated by changing the screw-in length.
  • the screw-in depth can be regulated with the aid of a gearwheel system 54 and a motor 55.
  • the motor is again controlled via the control unit 15, to which the values supplied by the temperature sensor 24 are fed.
  • the screw thread is expediently encapsulated in relation to the rest of the vacuum space in order to avoid contamination, or is protected against inert gas.
  • FIG. 6 shows a solution in which a plate system 61 is connected both to the cold head 4 and to a warm place.
  • the plates 62 are alternately connected to the cold head 4 and to the warm point 63.
  • the variation of the heat transfer for the purpose of keeping the target temperature constant takes place by a variation of the gas filling pressure by increasing the filling pressure in the plate system 61 if the temperature is too low.
  • the filling pressure can be applied with the aid of a bellows 64 and a motor 65, the motor 65 again being controlled as a function of the values supplied by the sensor 24.
  • a heat flow switch 71 is provided. It comprises the hollow rod 72, which is connected to the cold stage 4 and contains gas. Depending on the temperature, the gas expands or contracts the bellows attached to the lower end of the rod, the stamp 73 of which is assigned to the rod 74 connected to a hot spot. The contact of the heat flow switch is actuated by expansion or contraction of the gas in the rod 72.
  • a suitable bimetallic element or a suitable magneto- or electrostrictive element can also be present.
  • a hollow rod 81 which is filled with a suitably selected gas, is arranged between the cold stage 4 and a warm place.
  • a suitably selected gas which is preferably to be pumped under an increased pressure. It condenses in the area of cold level 4, then flows downwards and evaporates again in the area of the warm place.
  • a load on the cold stage 4 is achieved via this circuit. This load can be adjusted via the pressure or preferably by selecting suitable gases.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Compressors, Vaccum Pumps And Other Relevant Systems (AREA)

Abstract

The cryogenic pump (1) has a first refrigeration stage (4) to which pump faces (6, 7) are fixed and which is equipped with a heating device; in addition the cryogenic pump (1) has a second refrigeration stage (5) to which pump faces (10) are fixed and which during operation assumes a temperature of up to 20 K; in order to permit optimum pump characteristics with gases of differing vapour pressures, it is proposed that the heating device be controlled in such a way that the coldest point on the first refrigeration head (4) and/or its pump faces (6, 7) has a temperature which is 5 to 10 K higher than the vapour pressure temperature of the respective gas at maximum process pressure. <IMAGE>

Description

Die Erfindung bezieht sich auf ein Verfahren zur Adaption einer zweistufigen Refrigerator-Kryopumpe an ein bestimmtes Gas; die Kryopumpe weist eine erste Kältestufe auf, an der Pumpflächen befestigt sind und die mit einer Heizeinrichtung ausgerüstet ist; außerdem weist die Kryopumpe eine zweite Kältestufe auf, an der Pumpflächen befestigt sind und die während des Betriebes eine Temperatur zwischen ca. 10 und 20 K annimmt. Weiterhin bezieht sich die Erfindung auf zur Durchführung dieses Verfahrens geeig­nete Kryopumpen.The invention relates to a method for adapting a two-stage refrigerator cryopump to a specific gas; the cryopump has a first cooling stage, to which pumping surfaces are attached and which is equipped with a heating device; in addition, the cryopump has a second cooling stage, to which the pumping surfaces are attached and which takes on a temperature between approx. 10 and 20 K during operation. Furthermore, the invention relates to cryopumps suitable for carrying out this method.

Bei Kryopumpen dieser Art werden zum Einfangen von Gasen haupt­sächlich die physikalischen Vorgänge "Adsorption" und "Kondensa­tion" benutzt. Aufgrund dieser Vorgänge pumpt eine unkondi­tionierte, zweistufige Refrigerator-Kryopumpe problemlos in allen Druckbereichen unter 10⁻² mbar, solange sich die auftretenden Gase in drei Klassen einteilen lassen:

  • a) adsorbierbare Gase (H₂, Ne, He), bei T ≦ 20 K auf Adsorptionsflächen
  • b) kondensierbare erste Gase (N₂, O₂, Ar), bei T ≦ 20 K
  • c) kondensierbare zweite Gase (typisch: H₂O), bei T ≦ 150 K.
In cryopumps of this type, the physical processes "adsorption" and "condensation" are mainly used to trap gases. Due to these processes, an unconditioned, two-stage refrigerator cryopump can easily pump in all pressure ranges below 10⁻² mbar, as long as the gases can be divided into three classes:
  • a) adsorbable gases (H₂, Ne, He), at T ≦ 20 K on adsorption surfaces
  • b) condensable first gases (N₂, O₂, Ar), at T ≦ 20 K.
  • c) condensable second gases (typically: H₂O), at T ≦ 150 K.

Während beim Betrieb einer Kryopumpe für die zweite Stufe T₂ ≦ 20 K praktisch Betriebsvorschrift ist, kann sich die erste Stufe je nach Pumpengröße, -typ, Prozeß und je nach äußerer Belastung in weiten Bereichen von ca. 50 K bis 150 k einstellen.While the operation of a cryopump for the second stage T₂ ≦ 20 K is practical, the first stage can vary depending on the pump size, type, process and external load in a wide range from approx. 50 K to 150 k.

Dieser Sachverhalt ist beim Pumpen von Gasen wie Wasserdampf ohne direkte Auswirkung, kann aber beim Vorkommen von Gasen mit Dampfdruckkurven zwischen der von H₂O und der von O₂ und N₂ von besonderer Wichtigkeit sein. Beispiele für solche Gase sind CO, N₂O, CH₄ usw. Besonders kritisch wird es, wenn diese Gase unter variierenden Druckverhältnissen anfallen (10⁻³ bis 10⁻⁷ mbar). Ein in die Kryopumpe einfallendes Gasteilchen kondensiert nämlich auf seinem Weg innerhalb der Kryopumpe an der ersten Stelle, die gerade kalt genug ist, um das Teilchen zu binden. Aus der Dampf­druckkurve des jeweiligen Gases ist ablesbar, daß z. B. zur Bindung eines Gases bei einem Druck ≦ 10⁻⁷ mbar eine tiefere Temperatur erforderlich ist, als bei einem Druck von 10⁻³ mbar. Gase, deren Dampfdruckkurven zwischen den zuvor genannten kon­densierbaren ersten Gasen und den kondensierbaren zweiten Gasen liegen, können daher bei zunächst höherem Prozeßdruck an hinrei­chend kalten Stellen der ersten Stufe kondensieren. Will man anschließend zu tieferen Drücken abpumpen, dann gelingt dieses zum Teil nicht, da hierzu die erste Stufe nicht kalt genug ist. Das auf der ersten Stufe zuvor angefrorene Gas wandert bei einem Druck zwischen 10⁻³ und 10⁻⁷ mbar langsam hinüber zur zweiten Stufe, d. h. der Druck bleibt bei einem Zwischendruck stehen; die Pumpe scheint nicht mehr zu pumpen.This situation is of no direct effect when pumping gases such as water vapor, but can be of particular importance in the presence of gases with vapor pressure curves between that of H₂O and that of O₂ and N₂. Examples of such gases are CO, N₂O, CH₄ etc. It becomes particularly critical if these gases occur under varying pressure conditions (10⁻³ to 10⁻⁷ mbar). A gas particle falling into the cryopump condenses on its way inside the cryopump at the first point that is just cold enough to bind the particle. It can be read from the vapor pressure curve of the respective gas that, for. B. to bind a gas at a pressure ≦ 10⁻⁷ mbar, a lower temperature is required than at a pressure of 10⁻³ mbar. Gases, the vapor pressure curves of which lie between the previously mentioned condensable first gases and the condensable second gases, can therefore condense at sufficiently high process pressures at sufficiently cold points in the first stage. If you subsequently want to pump down to lower pressures, this is sometimes not possible because the first stage is not cold enough for this. The gas previously frozen on the first stage slowly migrates over to the second stage at a pressure between 10⁻³ and 10 zweiten mbar. H. the pressure remains at an intermediate pressure; the pump no longer seems to be pumping.

Aus der EU-PS 126 909 ist es bekannt, den Pumpflächen der ersten Stufe eine passive Wärmebelastung zu geben, indem die äußere Oberfläche des Strahlungsschirmes geschwärzt ist. Durch eine passive Last dieser Art läßt sich zwar die Temperatur der ersten Stufe auf einen Wert anheben, der oberhalb einer bestimmten Temperatur liegt; die Einhaltung eines festen Temperaturwertes ist jedoch nicht möglich. Mit steigender Belastung der Pumpe wird deshalb auch die ohnehin schon relativ hohe Temperatur der ständig belasteten ersten Stufe ansteigen, so daß die Effektivi­tät des Pumpverhaltens negativ beeinflußt wird. Weiterhin ist die passive Last nicht veränderbar, so daß eine Kryopumpe mit einer solchen Last zwar für das Pumpen von z. B. Argon geeignet sein mag, für Gase mit höheren Dampfdrücken jedoch nicht mehr. Bei diesen treten die beschriebenen Umlagerungen nach wie vor ein.From EU-PS 126 909 it is known to give the pumping surfaces of the first stage a passive heat load by blackening the outer surface of the radiation shield. A passive load of this type can indeed raise the temperature of the first stage to a value which is above a certain temperature; however, it is not possible to maintain a fixed temperature. With an increasing load on the pump, the already relatively high temperature of the constantly loaded first stage will therefore increase, so that the effectiveness of the pump behavior is negatively influenced. Furthermore, the passive load can not be changed, so that a cryopump with such a load for pumping z. B. argon may be suitable, but no longer for gases with higher vapor pressures. The described rearrangements still occur in these.

Ein weiterer Nachteil der passiven Last besteht darin, daß sie ständig vorhanden ist und damit die Kaltfahrzeit der Kryopumpe verlängert.Another disadvantage of the passive load is that it is always present and thus extends the cold running time of the cryopump.

Der vorliegenden Erfindung leigt die Aufgabe zugrunde, ein Verfahren der eingangs genannten Art sowie eine Kryopumpe zur Durchführung dieses Verfahrens anzugeben, welche bei Gasen mit unterschiedlichen Dampfdrücken ein optimales Pumpverhalten ermöglichen und bei denen die Kaltfahrzeit nicht beeinträchtigt ist.The present invention is based on the object of specifying a method of the type mentioned at the outset and a cryopump for carrying out this method, which enable optimum pump behavior in the case of gases with different vapor pressures and in which the cold driving time is not impaired.

Erfindungsgemäß wird diese Aufgabe dadurch gelöst, daß die Heizeinrichtung der ersten Stufe derart gesteuert wird, daß die kälteste Stelle der ersten Kältestufe bzw. ihrer Pumpflächen eine Temperatur annimmt, die um ca. 5 bis 10 K höher ist als die Temperatur, bei der der Dampfdruck des jeweiligen Gases gerade gleich dem höchsten vorkommenden Prozeßdruck ist. Diese Maßnahmen ermöglichen es ohne weiteres, die Temperatur der Pumpflächen der ersten Stufe auf ± 2 K genau konstant zu halten. Außerdem kann die Temperatur der ersten Stufe variiert werden, so daß jeder Pumpentyp an jedes Prozeßgas in gleicher Weise anpaßbar ist. Einen nachteiligen Einfluß auf die Kaltfahrzeit haben die erfin­dungsgemäßen Maßnahmen nicht, da die Steuerung erst bei der Soll-Temperatur einsetzt. Die Temperatur der ersten Stufe kann außerdem unabhängig von variierenden äußeren Belastungen konstant gehalten werden, da bei externer Belastungszunahme entsprechend weniger Heizleistung eingesetzt wird. Schließlich läßt sich die erfindungsgemäße Temperatursteuerung dazu verwenden, den Bela­stungszustand der Pumpe zu beobachten. Je höher die Belastung ist, desto seltener schaltet sich die Heizeinrichtung ein. Allgemein gesagt wird durch die aktive gesteuerte Heizbelastung der Zustand der Pumpe auch gegenüber wechselnder äußerer Bela­stung stabilisiert.According to the invention, this object is achieved in that the heating device of the first stage is controlled in such a way that the coldest point of the first cold stage or its pumping surfaces assumes a temperature which is approximately 5 to 10 K higher than the temperature at which the vapor pressure of the respective gas is just equal to the highest occurring process pressure. These measures make it possible without further ado to keep the temperature of the pumping surfaces of the first stage constant to within ± 2 K. In addition, the temperature of the first stage can be varied so that each type of pump can be adapted in the same way to each process gas. The measures according to the invention do not have an adverse influence on the cold driving time, since the control only starts at the target temperature. The temperature of the first stage can also be kept constant regardless of varying external loads, since less heating power is used when the external load increases. Finally, the temperature control according to the invention can be used to observe the load condition of the pump. The higher the load, the less often the heater switches on. Generally speaking, the state of the pump is also stabilized against changing external loads by the actively controlled heating load.

Weitere Vorteile und Einzelheiten der Erfindung sollen anhand von in den Figuren 1 bis 8 dargestellten Ausführungsbeispielen dargestellt werden.Further advantages and details of the invention are to be illustrated on the basis of the exemplary embodiments illustrated in FIGS. 1 to 8.

Die in den Figuren jeweils dargestellten Kryopumpen 1 mit dem Gehäuse 2 umfassen jeweils den nur teilweise dargestellten, zweistufigen Refrigerator-Kaltkopf 3, dessen Kältestufen mit 4 (erste Stufe) und 5 (zweite Stufe) bezeichnet sind. An der ersten Stufe 4 ist die topfförmige Pumpfläche bzw. Abschirmung 6 gut wärmeleitend befestigt, so daß diese gemeinsam mit dem von der Abschirmung 6 getragenen und gekühlten Baffle 7 den Innenraum 8 der Pumpe umschließt. Im Innenraum 8 befinden sich die Pumpflä­chen 10 der zweiten Stufe, welche gut wärmeleitend mit der zweiten Kaltkopfstufe verbunden sind. Der mit dem Baffle 7 ausgerüsteten Eintrittsöffnung 9 der Pumpe ist ein nur in Figur 1 dargestelltes Ventil 11 vorgelagert. Es umfaßt eine feste Scheibe 12 und eine drehbare Scheibe 13, welche jeweils im wesentlichen radiale Schlitzöffnungen aufweisen. Durch Drehen der Scheibe 13 kann das Ventil betätigt werden.The cryopumps 1 with the housing 2 each shown in the figures each comprise the only partially illustrated two-stage refrigerator cold head 3, the cooling stages of which are designated 4 (first stage) and 5 (second stage). At the first stage 4, the cup-shaped pump surface or shield 6 is fastened in a heat-conducting manner, so that it encloses the interior 8 of the pump together with the baffle 7 carried and cooled by the shield 6. In the interior 8 there are the pumping surfaces 10 of the second stage, which are connected to the second cold head stage with good thermal conductivity. The inlet opening 9 of the pump equipped with the baffle 7 is preceded by a valve 11 only shown in FIG. It comprises a fixed disk 12 and a rotatable disk 13, each of which has essentially radial slot openings. The valve can be actuated by rotating the disk 13.

Beim Ausführungsbeispiel nach Figur 1 weist das Gehäuse 2 der Kryopumpe 1 etwa in Höhe der Stufe 4 der ersten Refrigeratorstufe einen Anschlußstutzen 14 auf, der ein mit 15 bezeichnetes Über­wachungsgerät trägt. In diesem Gerät befindet sich eine Schaltung zur Versorgung von Heizeinrichtungen 16 und 17, mit denen die Kaltköpfe 4 und 5 des zweistufigen Kaltkopfes 3 ausgerüstet sind. Für die Verbindungsleitungen 18 und 19 zwischen dem Versorgungs­gerät 15 und den Heizeinrichtungen 16, 17 im Bereich von Flan­schen 21, 22 am Versorgungsgerät 15 bzw. am Anschlußstutzen 14 einen vakuumdichte Durchführung 23 vorgesehen.In the exemplary embodiment according to FIG. 1, the housing 2 of the cryopump 1 has a connecting piece 14 at approximately the level of the stage 4 of the first refrigerator stage, which supports a monitoring device denoted by 15. In this device there is a circuit for supplying heating devices 16 and 17 with which the cold heads 4 and 5 of the two-stage cold head 3 are equipped. A vacuum-tight bushing 23 is provided for the connecting lines 18 and 19 between the supply unit 15 and the heating devices 16, 17 in the region of flanges 21, 22 on the supply unit 15 and on the connecting piece 14.

In der Kryopumpe befindet sich ferner ein Temperatursensor 24, der an der Kältestufe 4 vorgesehen ist und dessen Meßleitung 26 ebenfalls zum Überwachungsgerät 15 führt. Mit diesem Überwa­chungsgerät 15 ist eine als Block dargestellte Versorgungseinheit 27 verbunden. Neben ihrer Funktion als Übertemperaturschutz beim Regenerieren mit elektrischen Heizern dient das Überwachungsgerät 15 dazu, die Einstellung der gewünschten Temperatur der Kälte­stufe 4 und der davon getragenen Pumpflächen bzw. Abschirmungen 6, 7 zu gewährleisten.In the cryopump there is also a temperature sensor 24, which is provided at the cold stage 4 and whose measuring line 26 also leads to the monitoring device 15. A supply unit 27, shown as a block, is connected to this monitoring device 15. In addition to its function as overtemperature protection when regenerating with electric heaters, the monitoring device also serves 15 to ensure the setting of the desired temperature of the cold stage 4 and the pumping surfaces or shields 6, 7 carried by it.

Dazu wird die Temperatur der Kältestufe 4 mit Hilfe des Sensors 24 gemessen. Dieser Meßwert wird dem Überwachungsgerät 15 zuge­führt. Dort wird dieser Meßwert mit einem Soll-Wert verglichen, der sich nach dem zu pumpenden Gas richtet. Liegt die Temperatur des Kaltkopfes unter diesem Soll-Wert, dann schaltet sich die Heizeinrichtung 16 so lange ein, bis die Soll-Temperatur erreicht ist, und anschließend wieder ab etc.For this purpose, the temperature of the cold stage 4 is measured using the sensor 24. This measured value is fed to the monitoring device 15. There, this measured value is compared with a target value, which depends on the gas to be pumped. If the temperature of the cold head is below this target value, the heating device 16 switches on until the target temperature has been reached, and then off again, etc.

In Figur 2 sind die Dampfdruckkurven verschiedener Gase darge­stellt. Da nach der Lehre der Erfindung die Heizeinrichtung derart zu steuern ist, daß die kälteste Stellt der ersten Kälte­stufe bzw. ihrer Pumpflächen eine Temperatur hat, die um 5 bis 10 K höher ist als die dem höchsten Prozeßdruck entsprechende Dampfdruck-Temperatur des zu pumpenden Gases, läßt sich aus der dargestellten Kurvenschar die jeweils einzustellende Soll-Tempe­ratur ablesen. Die Prozeßgase fallen in der Regel (z. B. bei Sputterprozessen) zunächst mit einem Druck von einigen 10⁻³ mbar an. Die 10⁻³ mbar-Linie schneidet die dargestellten Dampfdruck­kurven. Die einzustellende Temperatur ist deshalb ein Wert, der um 5 bis 10 K rechts vom Schnittpunkt der 10⁻³ mbar-Linie mit der zugehörigen Dampfdruckkurve liegt. Soll z. B. CH₄ gepumpt werden, dann ist die Temperatur der ersten Stufe bzw. ihrer Pumpflächen auf einen Wert von etwa 55 bis 60 K. Ist vorzugsweise NH₃ zu pumpen, dann ist eine Temperatur zu wählen, die bei etwa 130 bis 135 K liegt. Bei einer derartigen Temperaturwahl ist sicherge­stellt, daß das jeweils berücksichtigte Gas sich nicht auf der ersten Pumpstufe anlagert, sondern direkt von den Pumpflächen der zweiten Stufe gepumpt wird. Umlagerungen, die einen Druckabbau beim späteren Abpumpen auf < 10₋₃ mbar stören, treten nicht mehr auf.The vapor pressure curves of various gases are shown in FIG. Since, according to the teaching of the invention, the heating device is to be controlled in such a way that the coldest point of the first cooling stage or its pumping surfaces has a temperature which is 5 to 10 K higher than the vapor pressure temperature of the gas to be pumped which corresponds to the highest process pressure the target temperature to be set can be read from the family of curves shown. The process gases usually occur (e.g. in sputter processes) initially with a pressure of a few 10⁻³ mbar. The 10⁻³ mbar line intersects the vapor pressure curves shown. The temperature to be set is therefore a value that is 5 to 10 K to the right of the intersection of the 10⁻³ mbar line with the associated vapor pressure curve. Should z. B. CH₄ are pumped, then the temperature of the first stage or its pumping surfaces to a value of about 55 to 60 K. Is preferably NH 3 to be pumped, then a temperature should be selected which is about 130 to 135 K. With such a choice of temperature, it is ensured that the gas considered in each case does not accumulate on the first pump stage, but is pumped directly by the pump surfaces of the second stage. Rearrangements that interfere with a pressure reduction during later pumping to <10₋₃ mbar no longer occur.

Beim Ausführungsbeispiel nach Figur 1 sind beide Pumpstufen mit einer Heizeinrichtung 16, 17 ausgerüstet. Sie dienen - neben der Einstellung der Temperatur der Kältestufe 4 durch die Heizein­richtung 16 - der Regenerierung der Pumpflächen beider Stufen, indem diese Pumpflächen auf Zimmertemperatur aufgeheizt werden.In the exemplary embodiment according to FIG. 1, both pump stages are equipped with a heating device 16, 17. In addition to the setting of the temperature of the cooling stage 4 by the heating device 16, they serve to regenerate the pump surfaces of both stages by heating these pump surfaces to room temperature.

Beim Ausführungsbeispiel nach Figur 3 erfolgt die Gegenheizung der ersten Stufe durch Wärmestrahlung auf einen Ausschnitt der Abschirmung 6. Dazu ist das Gehäuse 2 der Kryopumpe 1 mit einem weiteren Anschlußstutzen 31 ausgerüstet. In diesem Anschluß­stutzen befindet sich eine Strahlungsquelle 32, die z. B. eine energiereiche Lichtquelle oder dergleichen sein kann. Durch eine geeignete Optik 35, deren Halterung gleichzeitig den vakuum­dichten Abschluß des Innenraumes 8 des Gehäuses 2 bildet, wird die von der Strahlungsquelle ausgehende Strahlung auf die äußere Oberfläche der Pumpfläche 6 konzentriert, welche zweckmäßig an dieser Stelle geschwärzt ist. Zur Steuerung der Strahlungsenergie ist wieder ein Temperatursensor 24 auf der Kältestufe 4 vorge­sehen, der seine Meßwerte an die Steuereinheit 27 liefert. Dort findet der Vergleich mit dem eingestellen Soll-Temperaturwert statt. Dementsprechend wird die Strahlungsquelle 32 ein- und ausgeschaltet oder in ihrer Leuchtkraft geregelt. Zweckmäßig an dieser Lösung ist, daß spannungsführenden Leitungen nicht im Innenraum der Kryopumpe verlegt werden müssen.In the exemplary embodiment according to FIG. 3, the first stage is counter-heated by heat radiation onto a section of the shield 6. For this purpose, the housing 2 of the cryopump 1 is equipped with a further connecting piece 31. In this connection piece there is a radiation source 32 which, for. B. can be a high-energy light source or the like. By suitable optics 35, the holder of which simultaneously forms the vacuum-tight seal of the interior 8 of the housing 2, the radiation emanating from the radiation source is concentrated on the outer surface of the pump surface 6, which is expediently blackened at this point. To control the radiation energy, a temperature sensor 24 is again provided on the cold stage 4, which supplies its measured values to the control unit 27. This is where the comparison with the set target temperature value takes place. Accordingly, the radiation source 32 is switched on and off or its luminosity is regulated. It is useful with this solution that live lines do not have to be laid inside the cryopump.

Figur 4 zeigt ein Ausführungsbeispiel, bei dem die Kältstufe 4 mit einem Wärmetauscher, hier in Form einer Rohrschlange 41 ausgerüstet ist. Durch diese Rohrschlange kann zur Gegenheizung der Kältestufe 4 warmes Gas, z. B. aus dem Helium-Kreislauf des Refrigerators, geführt werden. Der Aufheizung des Gases dient ein externer Wärmetauscher 42 mit einer elektrischen Heizung 43, die von der Steuereinheit 15 versorgt wird. Dieser Wärmetauscher liegt gemeinsam mit dem Ventil 44 in der Gaszuführungsleitung. Diese Anordnung ermöglicht zwei Verfahrensweisen zur Einstellung der Temperatur der Kältestufe 4. Entweder kann der Gasstrom geregelt werden, wenn das Ventil 44 als Dosierregelventil ausge­bildet ist. Eine andere Möglichkeit besteht darin, einen konstanten Gasstrom zuzuführen und die Temperatur des Gases mit Hilfe des Wärmetauschers geregelt aufzuheizen.Figure 4 shows an embodiment in which the cooling stage 4 is equipped with a heat exchanger, here in the form of a pipe coil 41. Through this coil, 4 warm gas, for. B. from the helium circuit of the refrigerator. An external heat exchanger 42 with an electric heater 43, which is supplied by the control unit 15, serves to heat the gas. This heat exchanger is located together with the valve 44 in the gas supply line. This arrangement enables two methods of adjusting the temperature of the cold stage 4. Either the gas flow can be controlled if the valve 44 is designed as a metering control valve. Another option is to get one supply a constant gas flow and heat the temperature of the gas in a controlled manner with the help of the heat exchanger.

Beim Ausführungsbeispiel nach Figur 5 ist an der Kältestufe 4 ein Bauteil 51 befestigt, das eine nach unten gerichtete Gewindeboh­rung 52 aufweist. In diese Gewindebohrung 52 ist ein Stab 53 ein­schraubbar, dessen freies Ende Zimmertemperatur hat oder aufge­heizt wird. Das Schraubgewinde bildet eine Wärmeaustauschfläche, deren Größe durch Veränderung der Einschraublänge regelbar ist. Mit Hilfe eines Zahnradsystems 54 und eines Motors 55 ist die Einschraubtiefe regelbar. Die Steuerung des Motors erfolgt wieder über die Steuereinheit 15, der die vom Temperaturfühler 24 gelie­ferten Werte zugeführt werden. Sinnvollerweise ist das Schraubge­winde zur Vermeidung von Kontaminationen gegenüber dem übrigen Vakuumraum verkapselt, bzw. inertgasgeschützt.In the exemplary embodiment according to FIG. 5, a component 51 is fastened to the cold stage 4 and has a downwardly directed threaded bore 52. A rod 53 can be screwed into this threaded bore 52, the free end of which has room temperature or is heated. The screw thread forms a heat exchange surface, the size of which can be regulated by changing the screw-in length. The screw-in depth can be regulated with the aid of a gearwheel system 54 and a motor 55. The motor is again controlled via the control unit 15, to which the values supplied by the temperature sensor 24 are fed. The screw thread is expediently encapsulated in relation to the rest of the vacuum space in order to avoid contamination, or is protected against inert gas.

Figur 6 zeigt eine Lösung, bei der ein Plattensystem 61 sowohl mit dem Kaltkopf 4 als auch mit einer warmen Stelle verbunden ist. Die Platten 62 sind abwechselnd mit dem Kaltkopf 4 und mit der warmen Stelle 63 verbunden. Die Variation des Wärmeüberganges zwecks Konstanthalten der Soll-Temperatur erfolgt durch eine Variation des Gasfülldruckes, indem bei zu niedriger Temperatur der Fülldruck im Plattensystem 61 erhöht wird. Der Fülldruck kann mit Hilfe eines Balges 64 und eines Motors 65 aufgebracht werden, wobei der Motor 65 wieder in Abhängigkeit von den vom Sensor 24 gelieferten Werten gesteuert wird.FIG. 6 shows a solution in which a plate system 61 is connected both to the cold head 4 and to a warm place. The plates 62 are alternately connected to the cold head 4 and to the warm point 63. The variation of the heat transfer for the purpose of keeping the target temperature constant takes place by a variation of the gas filling pressure by increasing the filling pressure in the plate system 61 if the temperature is too low. The filling pressure can be applied with the aid of a bellows 64 and a motor 65, the motor 65 again being controlled as a function of the values supplied by the sensor 24.

Beim Ausführungsbeispiel nach Figur 7 ist ein Wärmeflußschalter 71 vorgesehen. Er umfaßt den hohlen Stab 72, der mit der Kälte­stufe 4 verbunden ist und Gas enthält. Das Gas dehnt oder kontra­hiert je nach Temperatur den am unteren Ende des Stabes befe­stigten Balg, dessen Stempel 73 dem mit einer warmen Stelle verbundenen Stab 74 zugeordnet ist. Durch Ausdehnung bzw. Kon­traktion des Gases im Stab 72 wird der Kontakt des Wärmefluß­schalters betätigt.In the exemplary embodiment according to FIG. 7, a heat flow switch 71 is provided. It comprises the hollow rod 72, which is connected to the cold stage 4 and contains gas. Depending on the temperature, the gas expands or contracts the bellows attached to the lower end of the rod, the stamp 73 of which is assigned to the rod 74 connected to a hot spot. The contact of the heat flow switch is actuated by expansion or contraction of the gas in the rod 72.

Anstelle des Balges kann auch ein geeignetes Bimetallelement oder ein geeignetes magneto- oder elektrostriktives Element vorhanden sein.Instead of the bellows, a suitable bimetallic element or a suitable magneto- or electrostrictive element can also be present.

Bei der Kryopumpe nach Figur 8 ist zwischen der Kältestufe 4 und einer warmen Stelle ein Hohlstab 81 angeordnet, der mit einem geeignet ausgewählten Gas gefüllt ist. Dieses ist zweckmäßig das vorzugsweise zu pumpende Gas unter einem erhöhten Druck. Es kondensiert im Bereich der Kältestufe 4, fließt dann abwärts und verdampft wieder im Bereich der warmen Stelle. Über diesen Kreislauf wird eine Belastung der Kältestufe 4 erzielt. Über den Druck bzw. vorzugsweise durch Wahl geeigneter Gase ist diese Belastung einstellbar.In the cryopump according to FIG. 8, a hollow rod 81, which is filled with a suitably selected gas, is arranged between the cold stage 4 and a warm place. This is expediently the gas which is preferably to be pumped under an increased pressure. It condenses in the area of cold level 4, then flows downwards and evaporates again in the area of the warm place. A load on the cold stage 4 is achieved via this circuit. This load can be adjusted via the pressure or preferably by selecting suitable gases.

Claims (11)

1. Verfahren zur Adaption einer zweistufigen Refrigerator-­Kryopumpe (1) an ein bestimmtes Gas; die Kryopumpe weist eine erste Kältestufe (4) auf, an der Pumpflächen (6, 7) befestigt sind und die mit einer Heizeinrichtung ausgerüstet ist; außerdem weist die Kryopumpe (1) eine zweite Kältestufe (5) auf, an der Pumpflächen (10) befestigt sind und die während des Betriebes eine Temperatur von bis zu 20 K annimmt, dadurch gekennzeichnet, daß die Heizeinrichtung derart gesteuert wird, daß die kälteste Stelle des ersten Kaltkopfes (4) bzw. seiner Pumpflächen (6, 7) eine Temperatur hat, die um 5 bis 10 K höher ist als die zum maximalen Prozeßdruck gehörende Dampfdruck-Tempera­tur des jeweiligen Gases.1. Method for adapting a two-stage refrigerator cryopump (1) to a specific gas; the cryopump has a first cooling stage (4), to which the pump surfaces (6, 7) are attached and which is equipped with a heating device; in addition, the cryopump (1) has a second cooling stage (5), to which the pumping surfaces (10) are attached and which takes on a temperature of up to 20 K during operation, characterized in that the heating device is controlled in such a way that the coldest Place of the first cold head (4) or its pumping surfaces (6, 7) has a temperature which is 5 to 10 K higher than the vapor pressure temperature of the respective gas belonging to the maximum process pressure. 2. Kryopumpe zur Durchführung des Verfahrens nach Anspruch 1, dadurch gekennzeichnet, daß die Kälte­stufe (4) mit einem Temperatursensor (24) ausgerüstet ist und daß eine Steuereinheit (15) vorgesehen ist, die dem Vergleich des vom Temperatursensor gelieferten Signales mit einem Temperatur-Sollwert dient und die Heizeinrichtung entsprechend steuert.2. Cryopump for performing the method according to claim 1, characterized in that the cold stage (4) is equipped with a temperature sensor (24) and that a control unit (15) is provided, which the comparison of the signal supplied by the temperature sensor with a temperature Setpoint serves and controls the heating device accordingly. 3. Kryopumpe nach Anspruch 2, dadurch gekenn­zeichnet, daß eine von der Steuereinheit (15) ge­steuerte Strahlungsquelle (32) in einem Anschlußstutzen (31) am Gehäuse (2) der Kryopumpe (1) untergebracht ist.3. Cryopump according to claim 2, characterized in that a radiation source (32) controlled by the control unit (15) is accommodated in a connecting piece (31) on the housing (2) of the cryopump (1). 4. Kryopumpe nach Anspruch 3, dadurch gekenn­zeichnet, daß sich zwischen Strahlenquelle (32) und Pumpfläche (6) eine Optik (35) befindet.4. Cryopump according to claim 3, characterized in that there is an optics (35) between the radiation source (32) and pump surface (6). 5. Kryopumpe nach Anspruch 2, dadurch gekenn­zeichnet, daß der Kältestufe (4) ein Wärmetauscher (41) zugeordnet ist.5. Cryopump according to claim 2, characterized in that the cooling stage (4) is associated with a heat exchanger (41). 6. Kryopumpe nach Anspruch 2, dadurch gekenn­zeichnet, daß der Kältestufe (4) mit einem Bauteil (51) mit Gewindebohrung (52) ausgerüstet ist, in welchem ein an seinem freien Ende warmer Stab unterschiedlich tief ein­schraubbar ist.6. Cryopump according to claim 2, characterized in that the cooling stage (4) is equipped with a component (51) with a threaded bore (52) in which a warm rod at its free end can be screwed in at different depths. 7. Kryopumpe nach Anspruch 2, dadurch gekenn­zeichnet, daß der Kältestufe (4) ein Plattensystem (61) zugeordnet ist, dessen Platten (62) abwechselnd mit dem Kaltkopf (4) und mit einem warmen Abschnitt verbunden sind, un daß eine Vorrichtung zur Einstellung des Gasfülldruckes in dem Plattensystem vorgesehen ist.7. Cryopump according to claim 2, characterized in that the cold stage (4) is associated with a plate system (61), the plates (62) of which are alternately connected to the cold head (4) and to a warm section, so that a device for adjustment of the gas filling pressure is provided in the plate system. 8. Kryopumpe nach Anspruch 2, dadurch gekenn­zeichnet, daß der Kältestufe ein mechanischer Wärme­flußschalter zugeordnet ist, der je nach Schaltzustand die Kältestufe 4 mit einer wärmeren Stelle verbindet oder diese Verbindung unterbricht.8. Cryopump according to claim 2, characterized in that the cold stage is assigned a mechanical heat flow switch which, depending on the switching state, connects the cold stage 4 to a warmer point or interrupts this connection. 9. Kryopumpe nach Anspruch 8, dadurch gekenn­zeichnet, daß der Wärmeflußschalter durch ein geeig­netes in einen Zylinder oder Balg eingeschlossenes Gas betätigt wird, welches aufgrund seiner Kontraktion bei Abkühlung den Kontakt des Wärmeschalters betätigt.9. cryopump according to claim 8, characterized in that the heat flow switch is actuated by a suitable gas enclosed in a cylinder or bellows, which actuates the contact of the heat switch due to its contraction when cooling. 10. Kryopumpe nach Anspruch 2, dadurch gekenn­zeichnet, daß der Wärmetransport zur Kältestufe durch einen gasgefüllten, abgeschlossenen Wärmetransportstab ("Heat pipe") erfolgt, in dem sich ein geeignet ausgewähltes Gas befindet, das in dem Rohr so zirkuliert, daß es an der kalten Stelle zu Flüssigkeit kondensiert und von dort zur warmen Stelle zurückfließt und über diesen Kreislauf eine Belastung der Kältestufe (4) bewirkt.10. Cryopump according to claim 2, characterized in that the heat transport to the cold stage is carried out by a gas-filled, closed heat transport rod ("heat pipe") in which there is a suitably selected gas which circulates in the tube so that it is cold Place condenses to liquid and flows back from there to the warm place and causes a load on the cold stage (4) via this circuit. 11. Kryopumpe nach Anspruch 10, dadurch gekenn­zeichnet, daß das Gas im Wärmetransportstab das vorzugsweise zu pumpende Gas ist.11. Cryopump according to claim 10, characterized in that the gas in the heat transport rod is the gas which is preferably to be pumped.
EP88106497A 1988-04-22 1988-04-22 Method for the adaptation of a 2-stage cryogenic pump to a specific gas Expired - Lifetime EP0338113B1 (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
AT88106497T ATE72301T1 (en) 1988-04-22 1988-04-22 METHOD OF ADAPTING A TWO-STAGE REFRIGERATOR CRYOPUMP TO A SPECIFIC GAS.
EP88106497A EP0338113B1 (en) 1988-04-22 1988-04-22 Method for the adaptation of a 2-stage cryogenic pump to a specific gas
DE8888106497T DE3868264D1 (en) 1988-04-22 1988-04-22 METHOD FOR ADAPTING A TWO-STAGE REFRIGERATOR CRYOPUMP TO A PARTICULAR GAS.
US07/338,606 US4953359A (en) 1988-04-22 1989-04-14 Method of adapting a two-stage refrigerator cryopump to a specific gas
JP1097712A JP2668261B2 (en) 1988-04-22 1989-04-19 Method for adapting a two-stage refrigerator cryopump to a predetermined gas and a cryopump suitable for implementing the method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP88106497A EP0338113B1 (en) 1988-04-22 1988-04-22 Method for the adaptation of a 2-stage cryogenic pump to a specific gas

Publications (2)

Publication Number Publication Date
EP0338113A1 true EP0338113A1 (en) 1989-10-25
EP0338113B1 EP0338113B1 (en) 1992-01-29

Family

ID=8198909

Family Applications (1)

Application Number Title Priority Date Filing Date
EP88106497A Expired - Lifetime EP0338113B1 (en) 1988-04-22 1988-04-22 Method for the adaptation of a 2-stage cryogenic pump to a specific gas

Country Status (5)

Country Link
US (1) US4953359A (en)
EP (1) EP0338113B1 (en)
JP (1) JP2668261B2 (en)
AT (1) ATE72301T1 (en)
DE (1) DE3868264D1 (en)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4918930A (en) * 1988-09-13 1990-04-24 Helix Technology Corporation Electronically controlled cryopump
US6022195A (en) * 1988-09-13 2000-02-08 Helix Technology Corporation Electronically controlled vacuum pump with control module
US5157928A (en) * 1988-09-13 1992-10-27 Helix Technology Corporation Electronically controlled cryopump
US6318093B2 (en) * 1988-09-13 2001-11-20 Helix Technology Corporation Electronically controlled cryopump
US5305612A (en) * 1992-07-06 1994-04-26 Ebara Technologies Incorporated Cryopump method and apparatus
US6902378B2 (en) * 1993-07-16 2005-06-07 Helix Technology Corporation Electronically controlled vacuum pump
JP4927642B2 (en) * 2007-05-28 2012-05-09 キヤノンアネルバ株式会社 Operation control method for two-stage refrigerator, operation control method for cryopump using two-stage refrigerator, two-stage refrigerator and cryopump
JP4686572B2 (en) * 2008-05-14 2011-05-25 住友重機械工業株式会社 Cryopump, vacuum exhaust system, and diagnostic method thereof

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1508542A (en) * 1966-01-17 1968-01-05 Little Inc A Cryogenic pumps for very high vacuum
FR1553094A (en) * 1967-11-30 1969-01-10
WO1982003993A1 (en) * 1981-05-22 1982-11-25 Tech Corp Helix Improved cryopump
WO1984000404A1 (en) * 1982-07-06 1984-02-02 Helix Tech Corp Means for periodic desorption of a cryopump
EP0126909A2 (en) * 1983-04-04 1984-12-05 Helix Technology Corporation Cryopump with rapid cooldown and increased pressure stability
FR2572794A1 (en) * 1984-11-06 1986-05-09 Commissariat Energie Atomique Method for increasing the absorption capacity of a cryopumping pump and associated cryopumping pump
US4614093A (en) * 1985-04-06 1986-09-30 Leybold-Heraeus Gmbh Method of starting and/or regenerating a cryopump and a cryopump therefor

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4667477A (en) * 1985-03-28 1987-05-26 Hitachi, Ltd. Cryopump and method of operating same
US4679401A (en) * 1985-07-03 1987-07-14 Helix Technology Corporation Temperature control of cryogenic systems
DE3680335D1 (en) * 1986-06-23 1991-08-22 Leybold Ag Cryopump and method for operating this cryopump.

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1508542A (en) * 1966-01-17 1968-01-05 Little Inc A Cryogenic pumps for very high vacuum
FR1553094A (en) * 1967-11-30 1969-01-10
WO1982003993A1 (en) * 1981-05-22 1982-11-25 Tech Corp Helix Improved cryopump
WO1984000404A1 (en) * 1982-07-06 1984-02-02 Helix Tech Corp Means for periodic desorption of a cryopump
EP0126909A2 (en) * 1983-04-04 1984-12-05 Helix Technology Corporation Cryopump with rapid cooldown and increased pressure stability
FR2572794A1 (en) * 1984-11-06 1986-05-09 Commissariat Energie Atomique Method for increasing the absorption capacity of a cryopumping pump and associated cryopumping pump
US4614093A (en) * 1985-04-06 1986-09-30 Leybold-Heraeus Gmbh Method of starting and/or regenerating a cryopump and a cryopump therefor

Also Published As

Publication number Publication date
EP0338113B1 (en) 1992-01-29
JP2668261B2 (en) 1997-10-27
US4953359A (en) 1990-09-04
ATE72301T1 (en) 1992-02-15
DE3868264D1 (en) 1992-03-12
JPH01305173A (en) 1989-12-08

Similar Documents

Publication Publication Date Title
DE3427601C2 (en)
DE102006046688B3 (en) Cooling system, e.g. for super conductive magnets, gives a non-mechanical separation between the parts to be cooled and the heat sink
DE2802550A1 (en) EQUIPMENT FOR DRYING AIR BY THE CONDENSATION PROCESS
DE3333907C2 (en)
EP0338113B1 (en) Method for the adaptation of a 2-stage cryogenic pump to a specific gas
DE2147837B2 (en) COOLING DEVICE
DE1934938C3 (en) High vacuum pumping arrangement
EP0445503A1 (en) Two stage cryopump
DE1903643A1 (en) Method for cooling a consumer consisting of a partially stabilized superconducting magnet
DE3046458A1 (en) REFRIGERATOR CRYOSTAT
DE3229779C2 (en)
DE102004034729B4 (en) Cryostat arrangement with cryocooler and gas gap heat exchanger
DE1151261B (en) Device in a refrigerator to regulate the temperature of a cooling chamber independently of the temperatures in the other cooling chambers
DE4128881C2 (en) Device and method for reducing the temperature
DE2543075A1 (en) Cooling system for several grouped circuit components - has liquid evaporating in heat sink cavities and recondensing in external condenser
DE4114700A1 (en) METHOD FOR CONTROLLING THE TEMPERATURE OF A MEDIUM BY MEANS OF A TEMPERATURE CONTROL CIRCUIT AND TEMPERATURE CONTROL DEVICE FOR CARRYING OUT THE METHOD
EP0866291B1 (en) Compression heat pump or compression cooling machine and control method therefor
DE4409866C2 (en) Electric moisture sensor
DE19620105A1 (en) Operation of refrigerating plant
DE3801711A1 (en) METHOD FOR OPERATING A REFRIGERATION SYSTEM AND REFRIGERATION SYSTEM FOR IMPLEMENTING THE PROCESS
DE4321135A1 (en) Method for depositing a superconducting thin film
EP0705907B1 (en) Process and installation for cooling workpieces with gases
DE102020123960B4 (en) Method for operating a heat pump and heat pump
WO1989006335A1 (en) Refrigerating unit for refrigerator
EP3309478B1 (en) Method for operating a cooling circuit

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH DE FR GB IT LI NL

17P Request for examination filed

Effective date: 19900201

17Q First examination report despatched

Effective date: 19901108

ITF It: translation for a ep patent filed

Owner name: DE DOMINICIS & MAYER S.R.L.

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AT BE CH DE FR GB IT LI NL

REF Corresponds to:

Ref document number: 72301

Country of ref document: AT

Date of ref document: 19920215

Kind code of ref document: T

GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)
REF Corresponds to:

Ref document number: 3868264

Country of ref document: DE

Date of ref document: 19920312

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: NL

Payment date: 19920430

Year of fee payment: 5

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: AT

Payment date: 19930311

Year of fee payment: 6

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: CH

Payment date: 19930315

Year of fee payment: 6

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: BE

Payment date: 19930329

Year of fee payment: 6

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: NL

Effective date: 19931101

NLV4 Nl: lapsed or anulled due to non-payment of the annual fee
PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: AT

Effective date: 19940422

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LI

Effective date: 19940430

Ref country code: CH

Effective date: 19940430

Ref country code: BE

Effective date: 19940430

BERE Be: lapsed

Owner name: LEYBOLD A.G.

Effective date: 19940430

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 19970307

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 19970319

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 19970321

Year of fee payment: 10

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 19980422

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: THE PATENT HAS BEEN ANNULLED BY A DECISION OF A NATIONAL AUTHORITY

Effective date: 19980430

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 19980422

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 19990202

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20050422