EP0359336B1 - Dispositif pour la transmission des micro-ondes - Google Patents

Dispositif pour la transmission des micro-ondes Download PDF

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Publication number
EP0359336B1
EP0359336B1 EP89202301A EP89202301A EP0359336B1 EP 0359336 B1 EP0359336 B1 EP 0359336B1 EP 89202301 A EP89202301 A EP 89202301A EP 89202301 A EP89202301 A EP 89202301A EP 0359336 B1 EP0359336 B1 EP 0359336B1
Authority
EP
European Patent Office
Prior art keywords
waveguide
arrangement
microwave
pumping stage
pressure
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 - Lifetime
Application number
EP89202301A
Other languages
German (de)
English (en)
Other versions
EP0359336A2 (fr
EP0359336A3 (fr
Inventor
Georg Dr. Gärtner
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.)
Philips Intellectual Property and Standards GmbH
Koninklijke Philips NV
Original Assignee
Philips Patentverwaltung GmbH
Koninklijke Philips Electronics NV
Philips Electronics NV
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 Philips Patentverwaltung GmbH, Koninklijke Philips Electronics NV, Philips Electronics NV filed Critical Philips Patentverwaltung GmbH
Publication of EP0359336A2 publication Critical patent/EP0359336A2/fr
Publication of EP0359336A3 publication Critical patent/EP0359336A3/fr
Application granted granted Critical
Publication of EP0359336B1 publication Critical patent/EP0359336B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
    • H01P1/00—Auxiliary devices
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
    • H01P1/00—Auxiliary devices
    • H01P1/30—Auxiliary devices for compensation of, or protection against, temperature or moisture effects ; for improving power handling capability

Definitions

  • the invention relates to a waveguide for microwave transmission, the beginning of which is open to a room of high pressure and the end of which is open to a room of lower pressure.
  • the two spaces connected by the waveguide can contain different gas compositions.
  • DE-OS 36 22 614 discloses a process for the production of electrically conductive molded articles by reactive deposition from a gas phase which is activated by a microwave plasma.
  • high-power microwaves are coupled in via a gastightly insulating microwave window made of dielectric material into a microwave resonator serving as a reaction chamber, in which a plasma is formed and electrically conductive layers are deposited.
  • the microwave window arranged at the coupling point is usually covered with an electrically conductive layer on its surface facing the reaction chamber, ie on its inside, as a result of which the coupling is prevented.
  • this problem is solved either by flushing the inside of the microwave window with an inert gas or by choosing a dielectric material for the microwave window that is electrically conductive due to an etching reaction with one of the reactants Layer growth is kept free.
  • microwave powers of the order of 0.1 to 1 MW the thermal load on the known materials used for microwave windows becomes too great, as a result of which the output power is limited.
  • a maximum output of 0.3 MW one helps to widen the waveguide and the window, which e.g. consists of Al2O3, in addition to cooling.
  • means for maintaining a gas flow in the waveguide system are provided for ventilating a waveguide system, the gas flowing from the center of the waveguide system in opposite directions to both the beginning and the end of the waveguide system.
  • the invention has for its object to improve the microwave transmission between waveguide areas of different internal gas pressure and / or different filling gas composition.
  • the waveguide device has at least one low-radiation opening to which a pump is connected.
  • a pump stage is to be understood as a pump connection with a pump and pressure control, the pump always being outside the waveguide.
  • gas is pumped out at least at one point between the waveguide regions.
  • the pump stages can preferably be pressure-controlled, the flow resistances of the waveguide sections between the Pump stages, the suction power of the pumps and the pressure controls are dimensioned or adjustable in such a way that a predetermined pressure difference between the waveguide areas is generated and maintained - in other words: the suction power of the respective pump in the target pressure area is greater than or equal to the flow resistance of the waveguide section between the inlet or the pump stage with higher pressure and the pump-down point and the pressure control is set for the target pressure range at the pump-off point (at which there is also a pressure sensor or a manometer).
  • the respective pump stage is preferably in the immediate vicinity of the low-pressure side.
  • the waveguide guiding a particular microwave mode is provided with a slot or with slots at successive locations, the slot or slots having a very weak or negligible coupling-out of the microwave mode and the waveguide via the slot with the pump stage or is connected via the slots to successive pump stages with adapted pumping power.
  • This embodiment is based on the basic idea of differential pumping.
  • the waveguide is pumped out through the slots in successive pumping stages, so that the microwave is either guided from an area of high internal gas pressure (e.g. air under atmospheric pressure) to an area of low internal gas pressure (e.g. 10 hpa) in the waveguide or in the opposite direction from an area low is led into an area of high internal gas pressure.
  • an area of high internal gas pressure e.g. air under atmospheric pressure
  • an area of low internal gas pressure e.g. 10 hpa
  • the waveguide preferably has a rectangular cross section and is coiled several times.
  • the slots are preferably made in the waveguide side walls, namely in the narrow sides, and have the shape of vertical rectangles.
  • the distances between the slots are preferably integer multiples of half the waveguide wavelength.
  • resonance diaphragms are arranged in the waveguide.
  • a microwave window is arranged between the waveguide region connected to a microwave oscillator and the vacuum region generated by the (first) pump stage, the first pump stage being designed in such a way that it is able to generate such a low final pressure that no discharge is ignited.
  • a second pump stage is arranged between the first pump stage and a reaction chamber designed as a microwave resonator, in order to relieve the first pump stage and to remove gas from the reaction chamber.
  • the waveguide in the region of the first pump stage is filled with a gas with a high dielectric strength.
  • the pump stage consists of a double-walled resonance diaphragm, which is designed as a nozzle for a flat liquid jet of high speed.
  • the waveguide is filled with a purge gas, an extinguishing gas or reactive gases. This is explained in more detail below.
  • microwave transmission devices it is expedient to also provide at least one EH tuner and / or a pin transformer in the waveguide in order to carry out a phase or length adjustment and to tune for optimal power transmission.
  • the directional coupler areas lying between the waveguide areas each having short-circuit slides at the ends and one EH tuner each are provided to coordinate the transmission link. This is explained in more detail below.
  • a waveguide area with high pressure (e.g. air, 1000 hpa) is designated with a and a waveguide area with low pressure with b.
  • a microwave of the TE 10 type is guided either from a to b or from b to a in a multi-spiral curved rectangular waveguide line 1.
  • Pump nozzles 6, 7, 8, 9 are attached to the outside of these slots, via which the line in direction b is successively evacuated to a lower pressure using various vacuum pumps (not shown).
  • the pressure difference ⁇ p p a - p b to be set between a and b is determined by the suction power and the final pressure of the pumps, the number of pump stages, the spacing of the slots and the cross section of the respective waveguide type.
  • a large pressure difference is easier to achieve, for example, for the E-band (60 to 90 GHz) than for the X-band (8 to 12 GHz), because of the sharp reduction in cross-section of the E-band waveguide compared to the X-band Waveguide.
  • the device according to FIG. 1 is used for the microwave plasma-activated CVD of electrically conductive substances.
  • an X-band waveguide 1 is filled with air under p a ⁇ normal pressure and connected to an X-band microwave transmitter with a CW power of 300 W.
  • the spatial extent of this arrangement for the X-band is still quite compact with an outer diameter of approximately 37 cm and a height of approximately 30 cm.
  • Example 1 it is expedient to use a throttle valve or a pressure control in front of the pump to adjust p b in order to be able to adjust p b to the respective desired value.
  • another pump can be used for gas removal from the reaction chamber, which relieves the rotary vane pump at b.
  • a microwave coupling pressure lock according to FIG. 1 looks much cheaper for the E band (60 to 90 GHz). With a microwave transmission direction from b to a, it is also excellently suited for windowless coupling of microwaves of high power, for example 200 kW, from a 70 GHz gyrotron. Because of the already relatively small waveguide transverse dimensions, no resonance diaphragms are required in such an arrangement.
  • the arrangement shown in Fig. 3 relates to the use with a microwave plasma reactor.
  • the microwave transmission takes place through a Waveguide 1, which is sealed airtight at one point with a microwave window 11 made of dielectric material, for example glass, quartz, PTFE, against the vacuum side 12.
  • a working pressure of, for example, 10 hPa in the reaction chamber designed as a microwave resonator.
  • Another rotary vane pump pumps at two further opposite slots 4 and 5 at a distance L between the pump connection 13 and the coupling point into the reaction chamber (arrow 15) and serves both to relieve the pump at 13 and for gas disposal, ie for removal of the gaseous PCVD end products.
  • one or more resonance diaphragms 10 can be used in the (eg X-band) waveguide.
  • a gas prevents a plasma from forming in the waveguide in spite of the low gas pressure and thus almost no microwave power reaching the reaction chamber.
  • the microwaves are coupled into the reaction chamber via a coupling hole or via an antenna pin through a coupling hole.
  • the pump connection 13 is omitted and, for example, WF6 or SF6 is introduced at this point.
  • WF6 which serves for the tungsten deposition in the reaction chamber
  • the pump connection 14 and the slots 4 and 5 are also dispensed with, and the gas is disposed of at an outlet opening from the reaction chamber.
  • a further possibility is the use of one or more low-damping directional couplers with rectangular waveguides arranged in parallel, which are pumped or gas-purged separately and in which the coupling holes represent an additional flow resistance ("orifice plate").
  • an additional flow resistance orifice plate
  • a third embodiment of the invention is the jet microwave window.
  • Fig. 4 shows such an arrangement.
  • the microwaves (arrow 16) are radiated through a double-walled resonance aperture 17, which is designed as a nozzle 18 for a flat liquid jet (arrows 19 and 20) at high speed, again from an inner waveguide area of approximately atmospheric pressure into a low-pressure area.
  • nozzle jet microwave window is, inter alia, that no additional window cooling is required and that there is no longer any limitation at high microwave powers.
  • pumping action of the nozzle jet can also be exploited here, as is used, for example, in water jet pumps or in diffusion pumps. There is one Microwave transmission through a pump. In a further stage in the transition to high vacuum, a steam jet nozzle can then be used instead of a liquid jet nozzle.

Landscapes

  • Plasma Technology (AREA)
  • Drying Of Semiconductors (AREA)
  • Other Liquid Machine Or Engine Such As Wave Power Use (AREA)
  • Physical Or Chemical Processes And Apparatus (AREA)
  • Treatments Of Macromolecular Shaped Articles (AREA)
  • Waveguide Connection Structure (AREA)

Claims (16)

  1. Dispositif guide d'ondes pour la transmission de micro-ondes, dont l'entrée débouche sur un espace de haute pression et dont l'extrémité débouche sur un espace de basse pression, caractérisé en ce que le dispositif guide d'ondes présente au moins une ouverture exempte de rayonnement à laquelle une pompe est raccordée.
  2. Dispositif selon la revendication 1, caractérisé en ce que les étages de pompage (6, 7, 8, 9) sont réglables en pression, étant entendu que les résistances à l'écoulement des tronçons de guide d'ondes entre les étages de pompage, les puissances d'aspiration des pompes et les régulations de pression sont dimensionnées ou réglables, de telle sorte qu'une différence de pression prédéterminée soit produite et maintenue entre les zones (a, b) du guide d'ondes.
  3. Dispositif selon la revendication 1 ou 2, caractérisé en ce que l'étage de pompage respectif (6, 7, 8, 9) se trouve au voisinage le plus proche du côté de basse pression.
  4. Dispositif selon la revendication 1, 2 ou 3, caractérisé en ce que le guide d'ondes (1) acheminant un mode de micro-ondes déterminé est pourvu d'une fente ou, dans des endroits successifs, de plusieurs fentes (2, 3, 4, 5), la ou les fentes effectuant un découplage du mode de micro-ondes très faible voire même négligeable et le guide d'ondes étant raccordé, via la fente, à l'étage de pompage ou, via les fentes, à des étages de pompage successifs (6, 7, 8, 9) d'une puissance de pompage adaptée.
  5. Dispositif selon la revendication 4, caractérisé en ce que le guide d'ondes (1) a de préférence une section transversale rectangulaire et est enroulé en plusieurs hélices.
  6. Dispositif selon la revendication 4 ou 5, caractérisé en ce que les fentes (2, 3, 4, 5) sont de préférence ménagées dans les parois latérales du guide d'ondes, en fait dans les petits côtés, et ont la forme de rectangles verticaux.
  7. Dispositif selon la revendication 4, 5 ou 6, caractérisé en ce que les distances entre les fentes (2, 3, 4, 5) sont de préférence des multiples entiers de la demi-longueur d'onde du guide d'ondes.
  8. Dispositif selon la revendication 4, 5, 6 ou 7, caractérisé en ce que des écrans de résonance (10) soit agencés dans le guide d'ondes (1).
  9. Dispositif selon la revendication 1 ou 2, caractérisé en ce qu'une fenêtre à micro-ondes (11) est disposée entre la zone (16) du guide d'ondes raccordée à un oscillateur de micro-ondes et la zone de dépression (12) produite par l'étage (ou le premier étage) de pompage (13), le premier étage de pompage étant dimensionné, de telle sorte qu'il soit en mesure de produire une pression finale si basse qu'aucune décharge ne soit amorcée.
  10. Dispositif selon la revendication 9, caractérisé en ce qu'un deuxième étage de pompage (14) est agencé entre le premier étage de pompage (13) et une chambre réactionnelle qui se présente sous la forme d'un résonateur de micro-ondes pour décharger le premier étage de pompage et évacuer le gaz de la chambre réactionnelle.
  11. Dispositif selon la revendication 10, caractérisé en ce qu'au moins un écran de résonance (10) est disposé entre le premier étage de pompage (13) et le deuxième étage de pompage (14).
  12. Variante du dispositif selon la revendication 9, 10 ou 11, caractérisée en ce que le guide d'ondes (1) est rempli d'un gaz de haute rigidité diélectrique dans la zone du premier étage de pompage (13).
  13. Dispositif selon la revendication 1, caractérisé en ce que l'étage de pompage est constitué d'un écran de résonance (17) à double paroi, qui se présente sous la forme d'une buse pour injecter un flux de liquide étendu (19, 20) à grande vitesse.
  14. Dispositif selon la revendication 1, 2, 3 et/ou 10, caractérisé en ce que le guide d'ondes (1) est rempli d'un gaz de balayage, d'un gaz de coupage ou de gaz réactifs.
  15. Dispositif selon la revendication 1, 2 ou 8 caractérisé en ce qu'il est prévu dans le guide d'ondes (1) au moins un tuner EH et/ou un transformateur à pointes.
  16. Dispositif selon la revendication 1 ou 2, caractérisé en ce qu'entre les zones (a, b) du guide d'ondes sont agencées plusieurs coupleurs directifs successifs de faible amortissement, qui sont raccordés respectivement à une pompe pour régler une pression prédéterminée, les zones des coupleurs directifs situées entre les zones (a, b) du guide d'ondes étant équipées respectivement de pistons à piège aux extrémités et d'un tuner EH respectif pour accorder les tronçons de transmission.
EP89202301A 1988-09-16 1989-09-13 Dispositif pour la transmission des micro-ondes Expired - Lifetime EP0359336B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3831453A DE3831453A1 (de) 1988-09-16 1988-09-16 Vorrichtung zur mikrowellenuebertragung
DE3831453 1988-09-16

Publications (3)

Publication Number Publication Date
EP0359336A2 EP0359336A2 (fr) 1990-03-21
EP0359336A3 EP0359336A3 (fr) 1991-03-27
EP0359336B1 true EP0359336B1 (fr) 1995-12-06

Family

ID=6363043

Family Applications (1)

Application Number Title Priority Date Filing Date
EP89202301A Expired - Lifetime EP0359336B1 (fr) 1988-09-16 1989-09-13 Dispositif pour la transmission des micro-ondes

Country Status (4)

Country Link
US (1) US5028897A (fr)
EP (1) EP0359336B1 (fr)
JP (1) JPH02147847A (fr)
DE (2) DE3831453A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102011111884B3 (de) * 2011-08-31 2012-08-30 Martin Weisgerber Verfahren und Vorrichtung zur Erzeugung von thermodynamisch kaltem Mikrowellenplasma

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19529760C1 (de) * 1995-08-12 1996-11-14 Alcatel Kabel Ag Anordnung zur Übertragung von Hochfrequenz-Energie
EP1087458A3 (fr) * 1999-09-17 2002-08-07 Spinner GmbH Elektrotechnische Fabrik Filtre passe-bande
JP4636663B2 (ja) * 2000-10-11 2011-02-23 四国計測工業株式会社 高温高圧容器への化学反応促進用マイクロ波供給装置
DE102012204447B4 (de) 2012-03-20 2013-10-31 Forschungsverbund Berlin E.V. Vorrichtung und Verfahren zur Erzeugung eines Plasmas
US9928993B2 (en) * 2015-01-07 2018-03-27 Applied Materials, Inc. Workpiece processing chamber having a rotary microwave plasma antenna with slotted spiral waveguide

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2407069A (en) * 1942-09-15 1946-09-03 Gen Electric Dielectric wave guide system
GB644749A (en) * 1948-09-08 1950-10-18 Standard Telephones Cables Ltd Improvements in or relating to electromagnetic wave guides
DE1031383B (de) * 1956-04-19 1958-06-04 Philips Nv Vorrichtung zum Ventilieren eines Wellenleitersystems
US3287674A (en) * 1964-07-16 1966-11-22 Jr George H Stiegler Pressurized waveguide shut-off
US3778799A (en) * 1972-03-28 1973-12-11 Cables De Lyon Geoffroy Delore Safety device for pipe lines under gas pressure
US4286240A (en) * 1979-12-03 1981-08-25 Varian Associates, Inc. Circular electric mode microwave window
JPS60244102A (ja) * 1984-05-18 1985-12-04 Mitsubishi Electric Corp 導波管加圧装置
US4688007A (en) * 1985-09-03 1987-08-18 The Johns Hopkins University Air inlet for internal cooling of overmoded waveguide
DE3622614A1 (de) * 1986-07-05 1988-01-14 Philips Patentverwaltung Verfahren zur herstellung von elektrisch leitenden formkoerpern durch plasmaaktivierte chemische abscheidung aus der gasphase

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102011111884B3 (de) * 2011-08-31 2012-08-30 Martin Weisgerber Verfahren und Vorrichtung zur Erzeugung von thermodynamisch kaltem Mikrowellenplasma
WO2013029593A2 (fr) 2011-08-31 2013-03-07 Martin Weisgerber Dispositif de production de plasma micro-ondes thermodynamiquement froid

Also Published As

Publication number Publication date
DE58909526D1 (de) 1996-01-18
EP0359336A2 (fr) 1990-03-21
EP0359336A3 (fr) 1991-03-27
US5028897A (en) 1991-07-02
DE3831453A1 (de) 1990-03-22
JPH02147847A (ja) 1990-06-06

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