FR2655059A1 - Process and device for reactive cathode sputtering - Google Patents
Process and device for reactive cathode sputtering Download PDFInfo
- Publication number
- FR2655059A1 FR2655059A1 FR8915623A FR8915623A FR2655059A1 FR 2655059 A1 FR2655059 A1 FR 2655059A1 FR 8915623 A FR8915623 A FR 8915623A FR 8915623 A FR8915623 A FR 8915623A FR 2655059 A1 FR2655059 A1 FR 2655059A1
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- Prior art keywords
- sample
- reactive
- reactive gas
- gas
- plasma
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Classifications
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
- C23C14/22—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the process of coating
- C23C14/34—Sputtering
- C23C14/3464—Sputtering using more than one target
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
- C23C14/0021—Reactive sputtering or evaporation
- C23C14/0036—Reactive sputtering
- C23C14/0042—Controlling partial pressure or flow rate of reactive or inert gases with feedback of measurements
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
- C23C14/0021—Reactive sputtering or evaporation
- C23C14/0036—Reactive sputtering
- C23C14/0063—Reactive sputtering characterised by means for introducing or removing gases
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
- C23C14/0021—Reactive sputtering or evaporation
- C23C14/0036—Reactive sputtering
- C23C14/0073—Reactive sputtering by exposing the substrates to reactive gases intermittently
- C23C14/0078—Reactive sputtering by exposing the substrates to reactive gases intermittently by moving the substrates between spatially separate sputtering and reaction stations
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- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Physical Vapour Deposition (AREA)
Abstract
Description
La présente invention a pour objet un procédé de pulvérisation cathodique réactive d'une surface d'un échantillon. The present invention relates to a reactive cathodic sputtering process of a surface of a sample.
Un tel procédé est connu notamment pour déposer des films minces d'oxyde de cuivre présentant une quantité déterminée d'oxygène. L'article "Diode R.F. Sputtering of copper and copper oxide thin films and multilayers" de Pierre BOHER et al. paru dans Thin Solid Films 174 (1989) (compte-rendu de
Symposium on Trends and New Applications in Thin FilmslRatisbonne (RFA) 27 février - 3 mars 1989).Such a method is known in particular for depositing thin films of copper oxide having a determined quantity of oxygen. The article "Diode RF Sputtering of copper and copper oxide thin films and multilayers" by Pierre BOHER et al. published in Thin Solid Films 174 (1989) (review of
Symposium on Trends and New Applications in Thin FilmslRatisbonne (RFA) February 27 - March 3, 1989).
Selon la technique précitée, le plasma utilisé contient une certaine quantité d'oxygène, ce qui pose des problèmes d'oxydation de la cible, et impose en particulier de maintenir faible la teneur en oxygène. According to the aforementioned technique, the plasma used contains a certain amount of oxygen, which poses problems of oxidation of the target, and requires in particular to keep the oxygen content low.
L'invention se propose d'améliorer les paramètres de réaction de manière à obtenir des vitesses de croissance plus élevées sans que la cible réagisse avec le plasma réactif. The invention proposes to improve the reaction parameters so as to obtain higher growth rates without the target reacting with the reactive plasma.
Le procédé selon l'invention est ainsi caractérisé en ce que la plasma est essentiellement non réactif et en ce que du gaz réactif est introduit au voisinage de l'échantil- lon. The method according to the invention is thus characterized in that the plasma is essentially non-reactive and in that reactive gas is introduced in the vicinity of the sample.
Le plasma non réactif peut être un plasma argon. Le gaz réactif peut être de l'oxygène. The non-reactive plasma can be an argon plasma. The reactive gas can be oxygen.
L'invention concerne également un dispositif de pulvérisation cathodique réactive d'une surface d'un échantillon dans un plasma à partir d'une cible et comportant une chambre à vide, une installation de pompage, un premier dispositif d'introduction d'un premier gaz et un premier dispositif d'asservissement de la pression du premier gaz. The invention also relates to a device for reactive cathode sputtering of a surface of a sample in a plasma from a target and comprising a vacuum chamber, a pumping installation, a first device for introducing a first gas and a first device for controlling the pressure of the first gas.
Selon l'invention, le premier gaz est non réactif, et le dispositif comporte un deuxième dispositif d'introduction d'un gaz réactif au voisinage de l'échantillon. Il peut avantageusement comporter un deuxième dispositif d'asservissement de la pression partielle du gaz réactif. According to the invention, the first gas is non-reactive, and the device comprises a second device for introducing a reactive gas in the vicinity of the sample. It can advantageously include a second device for controlling the partial pressure of the reactive gas.
Selon un mode de réalisation avantageux, le deuxième dispositif d'introduction présente une section plate et évasée débouchant au voisinage de l'échantillon. According to an advantageous embodiment, the second introduction device has a flat and flared section opening out in the vicinity of the sample.
Le deuxième dispositif d'introduction peut avantageusement présenter un dispositif d'aiguillage ayant une première position pour laquelle le gaz réactif est dirigé vers la chambre à vide et une deuxième position pour laquelle le gaz réactif est dirigé vers l'installation de pompage. The second introduction device can advantageously have a switching device having a first position for which the reactive gas is directed towards the vacuum chamber and a second position for which the reactive gas is directed towards the pumping installation.
Selon un mode de réalisation préféré, le deuxième dispositif d'asservissement comporte un moyen pour mesurer la pression partielle de gaz réactif au voisinage de ladite cible, l'échantillon pouvant avantageusement être disposé entre la cible et l'installation de pompage. According to a preferred embodiment, the second control device comprises means for measuring the partial pressure of reactive gas in the vicinity of said target, the sample advantageously being able to be placed between the target and the pumping installation.
L'invention sera mieux comprise à la lecture de la description qui va suivre, donnée à titre d'exemple non limitatif, en liaison avec les dessins qui représentent - la figure 1 un schéma d'un dispositif selon l'invention. The invention will be better understood on reading the description which follows, given by way of nonlimiting example, in conjunction with the drawings which represent - FIG. 1 a diagram of a device according to the invention.
- la figure 2 une coupe verticale partielle d'un dispositif pour la mise en oeuvre de l'invention.- Figure 2 a partial vertical section of a device for the implementation of the invention.
- et la figure 3 une vue de dessus d'un bras d'introduction de gaz réactif selon un mode de réalisation particulièrement avantageux de l'invention.- And Figure 3 a top view of a reactive gas introduction arm according to a particularly advantageous embodiment of the invention.
Selon la figure 1, un dispositif de pulvérisation cathodique réactive comporte une chambre à vide 1 dans laquelle le vide est effectué par une pompe à diffusion 2. Un porte-échantillon(s) 3 sur lequel est disposé au moins un échantillon 4, peut être actionné à rotation autour de son axe pour mettre par exemple l'échantillon 4 en face de cibles successives 5 et 6 alimentées chacune par une installation radio-fréquence respectivement RF1 et RF2. According to FIG. 1, a reactive sputtering device comprises a vacuum chamber 1 in which the vacuum is produced by a diffusion pump 2. A sample holder (s) 3 on which is placed at least one sample 4, can be actuated in rotation about its axis to put for example the sample 4 in front of successive targets 5 and 6 each supplied by a radio-frequency installation RF1 and RF2 respectively.
En outre, des caches amovibles 7 et 8 permettent d'isoler temporairement un échantillon de la cible respectivement 5 et 6. In addition, removable covers 7 and 8 make it possible to temporarily isolate a sample from the target 5 and 6 respectively.
Un tuyau d'alimentation 11 comportant une vanne de régulation RV1 permet d'introduire dans l'enceinte à vide I par son extrémité 12 un gaz non réactif. La pression dans l'enceinte est mesurée par une sonde 10 qui fournit un signal à une entrée d'un dispositif de régulation de pression PR1 dont la sortie commande le degré d'ouverture de la vanne de régulation RV1. A supply pipe 11 comprising a regulation valve RV1 makes it possible to introduce a non-reactive gas into the vacuum enclosure I through its end 12. The pressure in the enclosure is measured by a probe 10 which supplies a signal to an input of a pressure regulating device PR1, the output of which controls the degree of opening of the regulating valve RV1.
Un tuyau d'alimentation 22 comportant une vanne de régulation RV2 permet d'introduire dans l'enceinte à vide 1 un gaz réactif par son extrémité 23 qui débouche en 24 à proximité de l'échantillon 4. A supply pipe 22 comprising a regulation valve RV2 makes it possible to introduce into the vacuum enclosure 1 a reactive gas by its end 23 which opens at 24 near the sample 4.
Un tuyau 29 associé à une micro-vanne V alimente un analyseur quadripolaire 20 comportant une pompe à vide 21. A pipe 29 associated with a micro-valve V feeds a quadrupole analyzer 20 comprising a vacuum pump 21.
L'analyseur quadripolaire 20 délivre un signal de sortie représentatif de la pression partielle de gaz réactif dans l'enceinte. Ce signal de sortie alimente un dispositif de régulation de pression PR2 dont la sortie commande le degré d'ouverture de la vanne de régulation RV2. The quadrupole analyzer 20 delivers an output signal representative of the partial pressure of reactive gas in the enclosure. This output signal feeds a pressure regulation device PR2, the output of which controls the degree of opening of the regulation valve RV2.
Deux vannes PV1 et PV2 commandées en alternance sont situées respectivement en amont du tuyau 23 et d'un tuyau 19 qui débouche dans la pompe à vide 2. Lorsque la vanne PV1 est ouverte et la vanne PV2 fermée (état 1), le système travaille en régulation de pression partielle de gaz réactif et un dépôt réactif peut être obtenu (p. ex. Cu0 avec une cible en Cu et 2 comme gaz réactif). Lorsque la vanne PV1 est fermée et la vanne PV2 ouverte (état 2), le système travaille en milieu non réactif et le système peut effectuer par exemple un dépôt métallique (p. ex. Cu). Le passage de l'état 1 à l'état 2 est rapide, car l'évacuation du gaz réactif ou bien la régulation de pression partielle prennent environ 1 à 3 secondes ce qui permet d'obtenir des couches alternées avec des interfaces bien définis. Two valves PV1 and PV2 controlled alternately are located respectively upstream of the pipe 23 and of a pipe 19 which opens into the vacuum pump 2. When the valve PV1 is open and the valve PV2 closed (state 1), the system works in partial pressure regulation of reactive gas and a reactive deposition can be obtained (eg Cu0 with a Cu target and 2 as reactive gas). When the PV1 valve is closed and the PV2 valve open (state 2), the system works in a non-reactive medium and the system can, for example, carry out a metallic deposition (eg Cu). The transition from state 1 to state 2 is rapid, since the evacuation of the reactive gas or else the partial pressure regulation takes approximately 1 to 3 seconds, which makes it possible to obtain alternating layers with well-defined interfaces.
On remarquera qu'il est particulièrement avantageux de disposer l'échantillon 4 entre la pompe à vide 2 et la cible 5 et de faire déboucher le tuyau 29 au voisinage de la ci ble 5 de manière à mesurer la pression partielle au niveau de la cible 5. C'est en effet la pression partielle au niveau de la cible 5 qui doit être maintenue suffisamment basse pour éviter sa réaction avec le gaz réactif (oxydation avec 2 comme gaz réactif, ou bien nitruration avec N2 comme gaz réactif). It will be noted that it is particularly advantageous to have the sample 4 between the vacuum pump 2 and the target 5 and to open the pipe 29 in the vicinity of the target 5 so as to measure the partial pressure at the target 5. It is indeed the partial pressure at the level of target 5 which must be kept low enough to avoid its reaction with the reactive gas (oxidation with 2 as reactive gas, or nitriding with N2 as reactive gas).
En outre, la proximité de la pompe à vide et de l'échantillon permet d'obtenir localement au niveau de l'échantillon 4 une pression partielle de gaz réactif plus élevée qu'au niveau de la cible 5. En d'autres termes, si on régule la pression partielle en gaz réactif au niveau de la cible 5 à une valeur voisine de la valeur maximale pour laquelle il n'y a pas de réaction de celle-ci avec le gaz réactif, on obtient au niveau de l'échantillon 4 une pression partielle de gaz réactif plus élevée et donc une vitesse de réaction accrue. Un résultat optimal est obtenu avec la pompe à vide 2 disposée au voisinage de l'échantillon 4 du fait de la conjugaison du flux de gaz réactif dirigé par l'extrémité 24 de tube 23 vers l'échantillon et le pompage 2 assure qu'une quantité minimale de gaz réactif se trouve au voisinage de la cible 5. In addition, the proximity of the vacuum pump and of the sample makes it possible to locally obtain at the level of the sample 4 a higher partial pressure of reactive gas than at the level of the target 5. In other words, if the partial pressure of reactive gas is regulated at target 5 to a value close to the maximum value for which there is no reaction of the latter with the reactive gas, one obtains at the level of the sample 4 a higher reactive gas partial pressure and therefore an increased reaction speed. An optimal result is obtained with the vacuum pump 2 placed in the vicinity of the sample 4 due to the combination of the flow of reactive gas directed by the end 24 of tube 23 towards the sample and the pumping 2 ensures that a minimum quantity of reactive gas is in the vicinity of target 5.
Selon les figures 2 et 3, le tube 23 se compose de trois sections, une section proximale 231 à laquelle est fixée un raccord 27 et une bride de maintien 25, une section centrale inclinée 232 en direction de l'échantillon 4 et une section distale 233 également inclinée en direction de l'échantillon 4 et formant un coude avec la section centrale 232. La section distale 233 se termine par un profil plat et évasé 24 qui permet de canaliser le flux de gaz réactif pratiquement parallèlement à la surface de l'échantillon 4. A cet effet la paroi 241 est pratiquement parallèle à l'échantillon 4. According to Figures 2 and 3, the tube 23 consists of three sections, a proximal section 231 to which is fixed a connector 27 and a retaining flange 25, a central section inclined 232 towards the sample 4 and a distal section 233 also inclined towards the sample 4 and forming an elbow with the central section 232. The distal section 233 ends in a flat and flared profile 24 which makes it possible to channel the flow of reactive gas practically parallel to the surface of the sample 4. For this purpose the wall 241 is practically parallel to the sample 4.
A la figure 2, on a représenté le porte-échantillon 31 qui pivote autour de l'axe 40 et le cache 7 qui pivote autour de l'axe 30. FIG. 2 shows the sample holder 31 which pivots around the axis 40 and the cover 7 which pivots around the axis 30.
Claims (11)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
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FR8915623A FR2655059A1 (en) | 1989-11-28 | 1989-11-28 | Process and device for reactive cathode sputtering |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR8915623A FR2655059A1 (en) | 1989-11-28 | 1989-11-28 | Process and device for reactive cathode sputtering |
Publications (1)
Publication Number | Publication Date |
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FR2655059A1 true FR2655059A1 (en) | 1991-05-31 |
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Application Number | Title | Priority Date | Filing Date |
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FR8915623A Withdrawn FR2655059A1 (en) | 1989-11-28 | 1989-11-28 | Process and device for reactive cathode sputtering |
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FR (1) | FR2655059A1 (en) |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4392931A (en) * | 1981-03-30 | 1983-07-12 | Northern Telecom Limited | Reactive deposition method and apparatus |
JPS6256570A (en) * | 1985-09-06 | 1987-03-12 | Tdk Corp | Reactive sputtering method |
GB2181461A (en) * | 1985-10-10 | 1987-04-23 | Canadian Patents Dev | Depositing semiconductor compounds by reactive sputtering |
JPS63151355A (en) * | 1986-12-16 | 1988-06-23 | Fuji Electric Co Ltd | Apparatus for preparing compound membrane |
-
1989
- 1989-11-28 FR FR8915623A patent/FR2655059A1/en not_active Withdrawn
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4392931A (en) * | 1981-03-30 | 1983-07-12 | Northern Telecom Limited | Reactive deposition method and apparatus |
JPS6256570A (en) * | 1985-09-06 | 1987-03-12 | Tdk Corp | Reactive sputtering method |
GB2181461A (en) * | 1985-10-10 | 1987-04-23 | Canadian Patents Dev | Depositing semiconductor compounds by reactive sputtering |
JPS63151355A (en) * | 1986-12-16 | 1988-06-23 | Fuji Electric Co Ltd | Apparatus for preparing compound membrane |
Non-Patent Citations (4)
Title |
---|
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A, vol. 3, no. 6, novembre/décembre 1985, pages 2129-2134, American Vacuum Society, New York, US; P.K. SRIVASTAVA et al.: "High rate reactive magnetron sputtered tungsten carbide films" * |
PATENT ABSTRACTS OF JAPAN, vol. 11, no. 251 (C-440)[2698], 14 août 1987; & JP-A-62 56 570 (TDK CORP.) 12-03-1987 * |
PATENT ABSTRACTS OF JAPAN, vol. 12, no. 421 (C-541)[3268],, 8 novembre 1988; & JP-A-63 151 355 (FUJI ELECTRIC CO., LTD) 23-06-1988 * |
THIN SOLID FILMS, vol. 128, no. 1/2, juin 1985, pages 149-159, Elsevier Sequoia, Lausanne, CH; G. SOBE et al.: "Deposition of Cr-Si thin films by reactive plasmatron-magnetron sputtering" * |
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