EP0145722B1 - Verfahren zum herstellen von schichten aus verbundwerkstoffen - Google Patents
Verfahren zum herstellen von schichten aus verbundwerkstoffen Download PDFInfo
- Publication number
- EP0145722B1 EP0145722B1 EP84901357A EP84901357A EP0145722B1 EP 0145722 B1 EP0145722 B1 EP 0145722B1 EP 84901357 A EP84901357 A EP 84901357A EP 84901357 A EP84901357 A EP 84901357A EP 0145722 B1 EP0145722 B1 EP 0145722B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- layer
- layers
- deposited
- spraying
- tin
- 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
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Classifications
-
- 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
- C23C18/00—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating
Definitions
- the present invention relates to a process for producing composite layers. It applies in particular to the production of electrodes for display cells with liquid medium and to the production of transparent heating parts allowing the defrosting of the panes for example.
- Methods for producing composite layers, for example constituted by a first layer of indium oxide doped with tin, deposited on a substrate for example of glass, and by a second layer of tin oxide doped with fluorine or antimony, deposited on the first layer.
- a first method known from French patent application No. 7,733,383 of November 7, 1977 (FR-A-2407,746), consists in depositing the first layer by radiofrequency sputtering, then annealing this first layer under vacuum. , then to deposit the second layer also by radiofrequency sputtering.
- This first method has the drawback of requiring a heat treatment (vacuum annealing) after the deposition of the first layer, so as to lower the resistivity of this layer to values compatible with the applications envisaged for the composite layers considered.
- the purpose of this vacuum thermal annealing is to increase the difference in stoichiometry, the main element of the conductivity of these oxides.
- a second method known from French patent application No. 7,038,371 of October 23, 1970 (FR-A-2 110 622), consists in depositing the first layer, by reactive chemical spraying of aerosols obtained by ultrasonic or pneumatic means, on the substrate, in a known device, provided for this purpose, and at a temperature above ambient temperature, the latter being of the order of 20 ° C; then to leave the device in question the assembly constituted by the substrate and the first layer, to bring this assembly to the open air and cool it down to ambient temperature; then replacing said assembly in the device; and depositing the second layer also by reactive chemical spraying of aerosols obtained by ultrasonic or pneumatic means, after having previously heated the substrate and the first layer.
- This second method has the disadvantage of requiring devices which are separate from the two layers, with return to air (at room temperature), after having deposited the first layer, and therefore due to the devices known for its implementation. not to allow to obtain indium oxide doped with tin of low electrical resistivity, that is to say electrical resistivity at most equal to 2,5-10- 4 ohm-cm.
- the electrical properties of the first layer are affected by the reduction in the stoichiometric difference of indium oxide, caused by the oxidation in air of this first layer during its cooling or its reheating prior to the deposition of the second layer.
- the object of the present invention is to remedy the above drawbacks by proposing a method which makes it possible to develop conductive composite layers of low electrical resistivity without heat treatment.
- Document FR-A-2 043 511 also discloses a system for the continuous treatment of parts, comprising a plurality of chambers containing determined atmospheres, as well as a plurality of transition zones, each zone being intended to isolate the one from the other two adjacent atmospheres.
- Said transition zone comprises, by means of introduction of another atmosphere which does not react with said atmospheres, and, on either side of the introduction means, means of evacuation of said other atmosphere.
- the ends of the transition zone are provided with openings for the passage of the pieces, the size of which is complementary to the section of these pieces.
- the present invention relates to a process for producing conductive composite layers, consisting of a first layer and a second layer, produced from chemical compounds, the layers being superimposed, this process consisting in depositing the first layer on a substrate then the second layer on the first layer, the first layer being made of indium oxide doped with tin, the second layer being made of tin oxide doped with one of the two fluorine or antimony elements, the layers being deposited by reactive chemical spraying at temperatures determined by the compounds to be deposited, a process characterized in that the second layer is deposited immediately after the first and in that a chemically inert atmosphere and a temperature close to the processing temperature of the first layer are maintained between each deposition, so that the first layer has a final electrical resistivity at most equal to 2 , 5.10-4 ohm - cm.
- chemically inert atmosphere or medium is meant, for example, an atmosphere of nitrogen or a rare gas.
- predetermined temperatures is meant the temperatures at which the reactive chemical sprays must be carried out and which are of course a function of the compounds to be deposited and the nature of the substrate or of the layers previously deposited.
- the deposition of the last layer is followed by cooling in ambient air of the composite layers obtained, the last layer acting as a protective barrier for all the other layers deposited before it.
- the substrate is for example made of an electrically insulating material such as glass.
- the composite layers obtained have a very low resistivity and also a high optical transmission.
- said reactive chemical spraying is an ultrasonic spraying.
- said reactive chemical spraying is a pneumatic spraying.
- the processing device used in the invention makes it possible to deposit the layers immediately one after the other, at temperatures suitable for each compound to be deposited, and to be able to maintain each layer, after its deposition and until the deposition of the next layer, in a chemically inert medium, so as to avoid any modification of the properties of the previous layers during their passage through the heating transfer means.
- FIG 1 there is shown schematically a particular embodiment of a device for implementing the method object of the invention, for producing composite layers constituted for example by a first electrically conductive layer 2, made of indium oxide doped with tin and deposited on an electrically insulating substrate 3 such as a glass plate, and by a second electrically conductive layer 4 made of tin oxide doped with fluorine or antimony and deposited on the first layer 2.
- a first electrically conductive layer 2 made of indium oxide doped with tin and deposited on an electrically insulating substrate 3 such as a glass plate
- a second electrically conductive layer 4 made of tin oxide doped with fluorine or antimony and deposited on the first layer 2.
- the device represented in FIG. 1 essentially comprises a first chamber 5a provided for the deposition of the first layer 2, a second chamber 5b provided for the deposition of the second layer 4, a heating transfer means 6 by means of which communicate the two chambers 5a and 5b, and means 7 for moving the substrate 3 from the first enclosure 5a to the second enclosure 5b via the transfer means 6.
- Each chamber 5a or 5b is provided with means 8a or 8b for depositing by spray layer 2 or 4 which corresponds to it.
- the device shown in FIG. 1 can be produced using a scrolling oven 9 which is arranged horizontally for example and on which are mounted vertically and one after the other, the two chambers 5a and 5b, so that they communicate with the scrolling oven 9. Said transfer means 6 is then constituted by the part of the scrolling oven 9 comprised between the two chambers 5a and 5b.
- the scroll furnace 9 naturally includes an inlet 10 and an outlet 11 respectively provided for the introduction of the substrate 3 into this furnace 9 and for the recovery of the substrate 3 provided with layers 2 and 4 once the latter has been formed.
- the scroll oven 9 further comprises a conveyor belt which constitutes said means 7 of movement.
- the scroll oven 9 could have more than two chambers communicating with it and placed one after the other, if it was desired to deposit more than two layers on said substrate.
- the scrolling oven 9 and the chambers 5a and 5b are provided with heating means 12, known in the prior art, for example electrical resistors, allowing the chambers and the scrolling oven, in particular in part 6 of that -between the two chambers, to be maintained at specified temperatures.
- heating means 12 known in the prior art, for example electrical resistors
- the transfer means 6 is filled with an inert atmosphere, for example constituted by nitrogen.
- the transfer means 6 is provided with conduits 13 which allow the introduction of nitrogen into said transfer means.
- Baffles 14 are arranged inside the transfer means 6 so that the layers are constantly bathed in a nitrogen atmosphere between the two consecutive chambers.
- Each chamber 5a or 5b has a shape, for example parallelepipedal, and laterally comprises a double wall 15a or 15b forming a pipe intended for the recovery of the reaction gases and of the nitrogen which are then evacuated by pipes 16 which open on either side. 'other of each room and which are connected to pumping means not shown. These conduits 16 also make it possible to evacuate other gases capable of being used in the invention as will be seen later.
- Each chamber 5a or 5b is connected by its lower part to the scrolling oven 9 and is closed at its upper part by a plug 17a or 17b which is crossed by a thermocouple 18a or 18b making it possible to control the temperature prevailing in the corresponding chamber 5a or 5b, and which is also provided with a window 19a or 19b making it possible to observe what is happening in said chamber 5a or 5b.
- the means 8a and 8b making it possible to deposit the layers 2 and 4 respectively are for example ultrasonic spraying means both constituted in the same way. It will be recalled that the ultrasonic spraying process is known in the state of the art under the name of "PYROSOL" and was the subject in particular of French patent 2110 622 filed on October 25, 1970 in the name of the French Atomic Energy Commission. .
- the spraying means 8a or 8b comprise a nozzle 20a or 20b constituted by a tube closed at its two ends and arranged horizontally inside the chamber 5a or corresponding 5b, towards the top thereof and perpendicular to the direction of movement of the treadmill 7. This tube is pierced with a plurality of holes 21 (FIG.
- An ultrasonic generator not shown, produces an aerosol transported by a carrier gas in the nozzle 20a or 20b provided with the row of holes 21 placed along a generator of the nozzle 20a or 20b. This aerosol is introduced into the nozzle 20a or 20b through a pipe 24 and exits through the holes 21.
- FIGS. 1 and 2 it can also be seen that the spraying means 8a or 8b are partly surrounded by a heat shield 27a or 27b.
- indium acetylacetonate is dissolved in indium acetylacetonate is dissolved in acetylacetone so as to give a solution 0.1 N.
- This solution is transformed into an aerosol thanks to an ultrasonic generator (frequency 800 kHz).
- This aerosol is directed by a stream of air (having a flow rate of approximately 10 liters per minute) in the nozzle 20a of the chamber 5a.
- the deposition temperature is about 500 ° C.
- the indium acetylacetonate solution used is doped with tin so that the Sn / In ratio is equal to 2.5 atom%.
- a 0.1 N tin tetrachloride solution in methanol is transformed into an aerosol as above by means of an ultrasonic generator (frequency 800 kHz).
- This aerosol is transported by a stream of air (having a flow rate of approximately 10 liters per minute) in the nozzle 20b of the chamber 5b.
- the operating temperature here is of the order of 450 ° C.
- the tin tetrachloride solution used is doped with fluorine so that the F / Sn ratio is equal to 5 atom%.
- the speed of the treadmill 7 is, in this example, of the order of 1 cm per minute.
- the composite layers are produced in the following way, again referring to FIG. 1: the substrate 3 is introduced into the scroll oven 9 through the inlet 10 thereof, brought in by the conveyor belt 7 to the first chamber 5a, in which it will be coated with the first layer 2 and then transported, still by the conveyor belt 7, to the second chamber 5b by the part 6 of the scrolling oven 9, intermediate between the two chambers, the first layer 2 being maintained in this case, at a temperature close to the temperature at which it had been produced (ie approximately 500 ° C.), until the time of the deposition of the second layer 4 carried out at approximately 450 ° C. .
- the substrate 3 provided with the first layer 2 is then covered with the second layer 4 during the travel in the second chamber 5b then evacuated by the conveyor belt 7 towards the outlet 11 where it is recovered, the cooling of the composite layers obtained then being able to s '' perform in air, up to room temperature.
- the second layer plays the role of protective layer of the first layer and prevents the oxidation of this first layer which could occur during said cooling.
- the respective thicknesses of the layers are determined by the quantities of the products respectively sprayed to obtain said layers in each of the two chambers and by the speed of travel of the conveyor belt 7.
- composite layers were obtained having the following characteristics:
- a layer of indium oxide doped with tin, 0.2 ⁇ m thick, deposited on a glass substrate, has a square resistance of the order of 25 Q (resistance of a square portion of layer any side for a current flowing between the two opposite sides of this square) and a resistivity of the order of 5 ⁇ 10 -4 ⁇ ⁇ cm.
- a layer of tin oxide doped with fluorine, 0.2 ⁇ m thick, on the preceding layer composite layers are obtained which have an overall square resistance of the order of 7 , 5 Q, therefore an overall resistivity of the order of 3.0 ⁇ ⁇ cm. Taking the resistivity of the fluorine-doped tin oxide layer the value of 6.1 10- 4 O.
- the tin-doped indium oxide layer the value of 2 10 -4 Q.cm. Indeed, in the first case, the indium oxide layer doped with tin oxidizes when it is cooled in air after its deposition and its resistivity increases, as a result of a reduction in the deviation from stoichiometry. On the contrary, in the second case, the fluorine-doped tin oxide layer prevents this oxidation in air and the resistivity of the protected layer remains low.
- the present invention therefore has advantages over the known methods for developing composite layers because it allows the protection of the covered materials against any degradation: for example the tin oxide layer deposited on the oxide layer. indium protects it from oxidation.
- the invention also makes it possible to permanently retain certain physical properties thanks to said protection: for example, thanks to the tin oxide layer, the resistivity of the indium oxide layer is kept constant and low.
- the superposition of the layers allows the creation of an interface which can be imposed by technology: for example, in the field of certain digital display cells in liquid medium, it is necessary to deposit the oxide layer. tin above the indium oxide layer.
- the products obtained can receive many applications: display cells, transparent heating parts, window insulation (reflection of infrared radiation).
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- Chemical & Material Sciences (AREA)
- General Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Surface Treatment Of Glass (AREA)
- Manufacturing Of Electric Cables (AREA)
- Chemically Coating (AREA)
- Other Surface Treatments For Metallic Materials (AREA)
Claims (3)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR8304565 | 1983-03-21 | ||
FR8304565A FR2543165B1 (fr) | 1983-03-21 | 1983-03-21 | Procede et dispositif d'elaboration de couches composites, par superposition, en continu et en atmosphere controlee |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0145722A1 EP0145722A1 (de) | 1985-06-26 |
EP0145722B1 true EP0145722B1 (de) | 1988-11-17 |
Family
ID=9287050
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP84901357A Expired EP0145722B1 (de) | 1983-03-21 | 1984-03-21 | Verfahren zum herstellen von schichten aus verbundwerkstoffen |
Country Status (6)
Country | Link |
---|---|
US (1) | US4618508A (de) |
EP (1) | EP0145722B1 (de) |
JP (1) | JPH0686655B2 (de) |
DE (1) | DE3475210D1 (de) |
FR (1) | FR2543165B1 (de) |
WO (1) | WO1984003720A1 (de) |
Families Citing this family (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4553853A (en) * | 1984-02-27 | 1985-11-19 | International Business Machines Corporation | End point detector for a tin lead evaporator |
FR2661623B1 (fr) * | 1989-04-04 | 1992-07-17 | Commissariat Energie Atomique | Systeme d'injection d'aerosol pour elaboration de couches composites par pyrolyse. |
US5190592A (en) * | 1990-05-02 | 1993-03-02 | Commissariat A L'energie Atomique | Aerosol injection system for producing composite layers by pyrolysis |
US20030070920A1 (en) * | 1997-05-01 | 2003-04-17 | Ashish Shah | Electrode for use in a capacitor |
US5920455A (en) * | 1997-05-01 | 1999-07-06 | Wilson Greatbatch Ltd. | One step ultrasonically coated substrate for use in a capacitor |
KR100477717B1 (ko) * | 1997-07-02 | 2005-07-12 | 삼성에스디아이 주식회사 | 산화인듐 입자의 제조방법 |
Family Cites Families (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR1353049A (fr) * | 1963-01-12 | 1964-02-21 | Saint Gobain | Procédé et dispositifs pour le traitement des articles en verre au cours de leur fabrication |
NL127687C (de) * | 1963-04-10 | |||
GB1307216A (en) * | 1969-04-23 | 1973-02-14 | Pilkington Brothers Ltd | Treating glass |
ES378214A1 (es) * | 1969-05-19 | 1973-01-01 | Ibm | Un sistema para tratar material, especialmente semiconduc- tor. |
JPS523418U (de) * | 1975-06-24 | 1977-01-11 | ||
US4048955A (en) * | 1975-09-02 | 1977-09-20 | Texas Instruments Incorporated | Continuous chemical vapor deposition reactor |
JPS52116896A (en) * | 1976-03-29 | 1977-09-30 | Matsushita Electric Ind Co Ltd | Electrode plate and its preparation |
FR2380997A1 (fr) * | 1977-02-16 | 1978-09-15 | Saint Gobain | Procede de fabrication de vitrages protegeant de la chaleur |
BE879189A (fr) * | 1978-10-19 | 1980-04-04 | Bfg Glassgroup | Procede de formation d'un revetement d'oxyde d'etain sur un support de verre chaud et produits ainsi obtenus |
GB2068935B (en) * | 1980-01-31 | 1983-11-30 | Bfg Glassgroup | Coating hot glass with metals or metal compounds especially oxides |
JPH05259888A (ja) * | 1992-03-13 | 1993-10-08 | Toshiba Corp | エミッタフォロア出力回路 |
-
1983
- 1983-03-21 US US06/682,352 patent/US4618508A/en not_active Expired - Fee Related
- 1983-03-21 FR FR8304565A patent/FR2543165B1/fr not_active Expired
-
1984
- 1984-03-21 JP JP59501346A patent/JPH0686655B2/ja not_active Expired - Lifetime
- 1984-03-21 DE DE8484901357T patent/DE3475210D1/de not_active Expired
- 1984-03-21 EP EP84901357A patent/EP0145722B1/de not_active Expired
- 1984-03-21 WO PCT/FR1984/000073 patent/WO1984003720A1/fr active IP Right Grant
Also Published As
Publication number | Publication date |
---|---|
JPH0686655B2 (ja) | 1994-11-02 |
DE3475210D1 (en) | 1988-12-22 |
FR2543165B1 (fr) | 1987-08-14 |
JPS60501115A (ja) | 1985-07-18 |
FR2543165A1 (fr) | 1984-09-28 |
EP0145722A1 (de) | 1985-06-26 |
WO1984003720A1 (fr) | 1984-09-27 |
US4618508A (en) | 1986-10-21 |
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