US3394066A - Method of anodizing by applying a positive potential to a body immersed in a plasma - Google Patents

Method of anodizing by applying a positive potential to a body immersed in a plasma Download PDF

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US3394066A
US3394066A US654009A US65400967A US3394066A US 3394066 A US3394066 A US 3394066A US 654009 A US654009 A US 654009A US 65400967 A US65400967 A US 65400967A US 3394066 A US3394066 A US 3394066A
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film
barrier
aluminum
plasma
anodizing
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John L Miles
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Arthur D Little Inc
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Arthur D Little Inc
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Priority to NL298098D priority Critical patent/NL298098A/xx
Priority to GB1052029D priority patent/GB1052029A/en
Priority to FR947995A priority patent/FR1375295A/fr
Priority to DE19631521815 priority patent/DE1521815A1/de
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Priority to US654009A priority patent/US3394066A/en
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
    • H01G9/00—Electrolytic capacitors, rectifiers, detectors, switching devices, light-sensitive or temperature-sensitive devices; Processes of their manufacture
    • H01G9/0029—Processes of manufacture
    • H01G9/0032—Processes of manufacture formation of the dielectric layer
    • 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
    • C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
    • C23C8/06—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases
    • C23C8/08—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases only one element being applied
    • C23C8/10—Oxidising
    • 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
    • C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
    • C23C8/06—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases
    • C23C8/36—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases using ionised gases, e.g. ionitriding
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B1/00—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B1/00—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
    • H01B1/02—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors mainly consisting of metals or alloys
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01C—RESISTORS
    • H01C17/00—Apparatus or processes specially adapted for manufacturing resistors
    • H01C17/06—Apparatus or processes specially adapted for manufacturing resistors adapted for coating resistive material on a base
    • H01C17/075—Apparatus or processes specially adapted for manufacturing resistors adapted for coating resistive material on a base by thin film techniques
    • H01C17/12—Apparatus or processes specially adapted for manufacturing resistors adapted for coating resistive material on a base by thin film techniques by sputtering
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N97/00—Electric solid-state thin-film or thick-film devices, not otherwise provided for

Definitions

  • ABSTRACT OF THE DISCLOSURE A method of forming a resistive barrier film on an electrically conducting body of an anodizable material through reaction of negative ions with the positive ions of the anodizable material. After the formation of a thin priming layer, the resistive barrier is caused to increase to a desired thickness by impressing an electrical potential across the priming layer.
  • This invention relates to a method for forming a resistive barrier film and to the resulting film produced thereby.
  • this invention relates to forming films capable of controlling the passage of electricity in circuits.
  • a layer of aluminum oxide having a consistent thickness throughout it is customary to anodize it.
  • the now-well-known process of anodizing comprises immersing the aluminum article in a liquid electrolyte and applying a potential across it such that negatively charged oxygen ions, derived from the electrolyte, are directed to the surface of the aluminum article serving as the anode in the circuit.
  • this type of oxidation which may be termed wet anodization to contrast with the method described herein, has been applied successfully to many other metals including, but not limited to, tantalum, titanium, zirconium, niobium, uranium, berryllium, manganese, magnesium and the like.
  • tantalum, titanium, zirconium, niobium, uranium, berryllium, manganese, magnesium and the like there are certain inherent disadvantages in forming oxide films on many of these metals by the wet anodization process.
  • aluminum oxide appears very attractive as an electron barrier material (either as an insulation or as a dielectric layer for tunneling).
  • an electron barrier material either as an insulation or as a dielectric layer for tunneling.
  • the former technique it carried out at room temperature, limits the ultimate thickness of the aluminum oxide film; and if carried out at elevated temperature requires intense heating of the device being formed.
  • wet anodizing offers the possibility of forming thicker films of aluminum oxide, of controlling the thickness of the oxide, and of making a film of uniform thickness there are associated with this process a number of inherent disadvantages.
  • these disadvantages may be listed the necessity for immersing the article in an electrolyte, the possibility that the film formed is soluble or partially soluble in the electrolyte, the strong probability that the film will have included within it constituents derived from the electrolyte that leave weak spots, and finally the limitation on the type of negatively charged ions which can be furnished by the electrolyte and hence upon the chemical characteristics of the barrier film itself.
  • both the metal and the barrier film surface are limited in quality and kind.
  • the invention accordingly comprises the several steps and the relation of one or more of such steps with respect to each of the others, and the article possesses the features, properties and relation of elements which are exemplified in the following detailed disclosure, and the scope of the invention will be indicated in the claims.
  • FIG. 1 is one modification of an apparatus suitable for carrying out the method of this invention
  • FIG. 2 is a diagrammatic representation showing the formation of a barrier film
  • FIG. 3 is a series of plots of current versus voltage for four aluminum oxide films of varying thickness formed by thermal oxidation and by the method of this invention using an external voltage source;
  • FIG. 4 is another modification of the apparatus showing the use of liquid nitrogen for condensation of moisture
  • FIG. 5 illustrates an evaporated test pattern
  • FIG. 6 is a much enlarged view of one of the crossovers in the test pattern of FIG. 5;
  • FIG. 7 is a much enlarged cross-sectional view of the actual cross-over
  • FIG. 8 is a plot of barrier thickness buildup vs. discharge exposure time
  • FIGS. 9a and 9b are contour maps of resistances with and without the use of an extremely thin layer of aluminum under the test pattern
  • FIG. 10 is a top plan view of a cryotron formed using the method of this invention.
  • FIG. 11 is a cross-sectional view showing the construction of the cryotron of FIG. 10.
  • the method of this invention can be briefly described as comprising the steps of forming a priming barrier on the surface of an electrically conducting body by reaction with a gaseous reactant, exposing the barrier to a plasma comprising negatively charged ions of the gaseous reactant, and impressing across the priming barrier an electrical potential to increase the thickness of the priming barrier and form the resistive barrier film which is characterized as being the reaction product of the negatively charged ions and the conducting material.
  • negatively charged ions are of a species which form with the conducting body material a compound which in film form is capable of controlling the passage of electricity.
  • the step of impressing an electrical potential across the priming barrier may be accomplished either by providing an external source of electrical current such as by contact with an electrode which is part of a suitable circuit for supplying an electron current, or by providing a sufficient supply of negatively charged ions on the priming barrier surface to establish a potential between these negative ions and the positive ions within the conducting body.
  • the resulting resistive barrier is characterized as being of consistent thickness throughout, essentiall free of occluded materials, and completely controllable with respect to its thickness.
  • the film need not be an oxide and the surface on which it is formed need not be a metal or be restricted as heretofore was the case.
  • FIG. 1 shows a bell jar 10 which defines within its interior an atmosphere of reduced pressure or plasma 11.
  • the bell jar is evacuated to from about 10* to 10 mm. mercury.
  • a vacuum line 12 with a suitable check valve 12a connects the bell jar to a vacuum pump (not shown).
  • the bell jar itself rests upon a metal electrically grounded base 20 which in turn sits upon a base support 21 and is afiixed to a foundation 22. Any other suitable ground other than base 20 may be supplied if it is not convenient to use the base as the ground.
  • the required negative ions of the gaseous reactant are provided in the necessary ionized state through the establishment of an electrical field which in FIG. 1 is formed between the high voltage electrode 24 and the electrically grounded base 20.
  • the high voltage electrode 24 is in turn connected through the wall of the bell jar by means of a vacuum-tight seal through a high voltage line 25 to a suitable power source 26.
  • a switch 27 is provided in high voltage line 25.
  • the electrode 28 (which for convenience is referred to as the anodizing electrode) enters the interior of the bell jar through a vacuum'tight seal, and through power line 29 is connected to a power source 30.
  • FIG. 1 illustrates the use of DC power.
  • An AC source of electricity may be used equally well for the anodizing electrode 28 and high voltage electrode 24; but the DC source is preferred inasmuch as deposition of the film barrier will of course take place only during half of the AC cycle.
  • the aluminum 16 After the aluminum 16 has been deposited upon the slide it is raised in position so that that film which is to be coated is brought into contact with the anodizing electrode 28. A small amount of dry purified oxygen gas is then introduced through line into the bell jar. It has been found that the oxygen pressure in the bell jar has two optimum values namely about 1 mm. mercury and about 50 microns mercury. Either of these pressure levels may be used in the process. Other pressures may also of course be used but these have been found to be optimum for oxygen and aluminum. If desired, an inert gas such as argon may be mixed with the ionized reactant gas in the bell jar. The oxygen present is then ionized by connecting the high voltage electrode 24 to the power source 26 through switch 27 and the anodizing circuit is completed by closing switch 33 making the necessary connection between the power source 30 and the anodizing electrode 28.
  • an inert gas such as argon
  • the thickness of the barrier film is controlled by the amount of voltage supplied by power source 30.
  • the anodizing voltage In the operation of the apparatus of FIG. 1, it has been found convenient to increase the anodizing voltage gradually, or by increments. Normally it is preferred to start with a low voltage, for example of the order of 1.5 volts, and observe the current flow. When this has decreased to a small value the voltage is increased by another increment and the process repeated until the desired thickness of barrier film has been built up.
  • FIG. 2 it will be seen that there is provided a conducting body of a material M having a surface S on which the protective barrier is to be built.
  • the barrier film itself has a surface S
  • the positive ions can readily diffuse in the resistive barrier and, under the influence of the field or concentration gradient, are capable of drifting across the barrier to combine with the negative ions on the surface.
  • the field across the resistive barrier becomes insufiicient to effect any further solubility of the positively charged ions in the barrier it is necessary to increase the field strength to force more of the positive ions to diffuse through the barrier.
  • This is readily shown (as indicated above in connection with the description of the operation of the apparatus of FIG. 1) by the necessity for periodically increasing the anodizing voltages.
  • the barrier has reached a thickness where the potential across it no longer causes solubility and diffusion of the positive ions in it, no more positive ions are available at surface S for reaction with negative ions.
  • application of additional potential will enable the barrier formation to begin again.
  • the physical properties of the aluminum oxide films formed in accordance with this invention were evaluated to compare with films formed by other techniques. To do this, aluminum oxide films were formed on pure aluminurn surfaces which in turn had been deposited by vacuum deposition techniques on a glass microscope slide. All samples were formed by depositing a 1 mm. wide strip of aluminum on the slide, then forming the oxide layer as indicated and finally depositing another 1 mm. wide strip of aluminum at right angles to the first. Voltagecurrent characteristics were measured by a four-probe method. Table 1 summarizes the data obtained and FIG. 3 is a plot of selected data obtained on samples prepared in the same manner. In FIG. 3 curves 2, 3 and 4 repre sent performances for Examples 12, 3 and 8 respectively; while curve 1 represents the performance of a typical thermally produced oxide film.
  • Examples 1-9 were formed using DC current while Examples 1012 were formed using AC current.
  • Examples 5, 6, 8 and 9 were formed using an oxygen plasma pressure of 1 mm. mercury and Examples 14, 7 and 10-12 using a plasma pressure of 50 microns mercury.
  • FIG. 1 illustrates an apparatus wherein this potential is applied from an external source.
  • FIG. 4 illustrates apparatus wherein such an external source of current is not employed.
  • an oxygen (or other gaseous) plasma negatively charged ions are furnished at the surface S of the resistive barrier as shown in FIG. 2. If a sufiicient number of these negatively charged ions are present at surface S then an external current is not necessary since the required electrical potential will be established between these negative ions and the positive ions in the conducting body. It is, therefore, not necessary in the apparatus of FIG. 4 to supply the external circuitry or the anodizing electrode 28.
  • FIG. 4 illustrates an additional feature, that of the use of a well 40 extending into the evacuated bell jar 10 and containing a cryogenic fluid such as liquid nitrogen 41.
  • a well 40 extending into the evacuated bell jar 10 and containing a cryogenic fluid such as liquid nitrogen 41.
  • the purpose of the well is to afford a refrigerated surface within the bell jar on which moisture vapor will condense. This has been found to be one effective way of reducing the moisture content within the bell jar. Of course other ways of reducing or minimizing water vapor content may be used, such as baking the system at elevated temperatures.
  • a resistive barrier layer in apparatus of FIG. 4 the same steps are performed as in the use of the apparatus of FIG. 1, beginning with the step of building up a priming layer on the conducting body surface, and then impressing an electrical potential across the priming layer to effect the growth of the resistive barrier.
  • the priming layer forms spontaneously with the introduction of the plasma or spontaneously with the residual gases present in the vacuum system.
  • the following description will again be given in terms of an aluminum oxide barrier layer on an aluminum surface. However, it is not meant to restrict the process of this invention to the formation of aluminum oxide on aluminum.
  • the oxygen plasma discharge was turned on by closing switch 27 for two minutes.
  • the discharge was turned oif two rows comprising 20 electrodes were then completed by evaporating conducting metal strips 48 to intersect lower electrodes 46 and form cross-over test areas 49 having A1 0 barrier layers.
  • the plasma discharge was turned on again for a brief period and an additional 20 cross-over areas completed by forming upper electrodes 48 on them.
  • five different data points were obtained each represented by 20 individual crossings having A1 0 layers of increasing thicknesses.
  • the resistances of each of the cross-over areas (A1 0 barrier films) were measured by applying current and measuring the voltage as indicated in FIG. 6.
  • Thicknesses of the A1 0 films formed were then calculated from these resistances and plotted against time of exposure to the oxygen plasma in FIG. 8. These data illustrates that it is possible to build up resistive barrier layers in this manner, and to control thicknesses very accurately and conveniently.
  • FIGS. 57 In constructing a number of test patterns such as illusstrated is FIGS. 57 it was found that in general the resistances of the cross-over areas near the edges and in the corners of the patterns were higher for a given discharge exposure time. It is believed that the presence of water vapor exerts some influence on the growth of the barrier films, particularly on those specimens close to the edges where it would have a lesser distance to travel to the films. Thus it is preferable in some applications to remove or counteract the effect of the water vapor to minimize the variation in aluminum oxide thickness and hence resistivity of the barrier.
  • the glass substrate (or any other substrate) also has water vapor associated with it and it has been found that a major portion of this water vapor can be removed or at least partially counteracted by baking or by depositing an extremely small amount of aluminum on the substrate surface before depositing the conducting body on which the resistive barrier is to be built.
  • this initial alumin um film is sufiiciently thin so that it is nonconducting. Hence, it need not be a continuous film.
  • FIG. 9a represents the resistances measured over that portion of the slide which contained the initial nonconducting layer of aluminum. It will be seen that the maximum variation in resistance lay between 8 and 12 ohms.
  • FIG. 9b resistances were plotted as a contour map for the lower half which did not receive the initial nonconducting aluminum film. Here it will be seen that resistance varied between 15 and 40 ohms, or by a factor of three.
  • the materials on which the barrier films may be built may be defined as those which are capable of conducting an electrical current. This means that they will normally be metals, although they are not limited to metals since non-metallic materials such as silicon and germanium are conductors.
  • the electrically conducting materials must also be capable of forming with the negatively charged ions a compound which itself, in film form, is capable of controlling the passage of an electrical current. Normally this means that the film barriers will be insulators, although when sufiiciently high voltages are applied su stantially tunneling or field emission currents may flow.
  • the materials from which the electrically conducting body may be formed include, but are not limited to, aluminum, magnesium, antimony, bismuth, tantalum, chromium, beryllium, niobium, titanium, zirconium, tungsten, boron, lead, silicon and germanium.
  • the negative ions may be any ions which are capable of reacting with the conducting metal to form a compound which in film form is capable of controlling the passage of an electron current.
  • the most common of these are, of course, oxygen ions.
  • some nitrides and sulfides are known to be resistive and thus nitrogen ions and sulfide ions are within the scope of this inven- TABLE 2.-FORMATION OF MAGNESIUM OXIDE FILMS Calculated MgO Measured Measured Example N0. Film Thickness, Capacitance, tan loss 1 A. rt/cm. l
  • an antimony oxide barrier film was formed on an antimony surface and a tantalum oxide barrier film on tantalum.
  • the antimony oxide film had a capacitance value of 0.5 af/cm. and a tan 6 loss of 0.08.
  • the tantalum oxide film exhibited the normal interference colors associated with tantalum oxide formed by anodization using a liquid electrolyte.
  • an electrical resistive barrier film of lead oxide was formed on a lead film and of silver oxide on a silver film.
  • the lead or silver film was deposited on a glass slide from the vapor phase.
  • dry oxygen was continuously circulated through the vacuum bell jar at a pressure of 50' microns. This continual pumping of oxygen through the system serves to flush out at least :a portion of any moisture present in the system. While oxygen was thus being supplied the switch 27 was closed to ionize the oxygen and provide the necessary oxygen ion plasma.
  • the resistive barrier films were allowed to build up for about 30 minutes under the conditions described.
  • the lead oxide film thus formed had a breakdown voltage of about 0.5 volt.
  • the ability to form an insulation layer of lead oxide directly on the lead film takes on great significance and offers a materially improved technique in the formation of these thin film circuits.
  • the resistive barrier layer of silver oxide on silver film grew very thick and very rapidly in these experiments.
  • the barrier of silver oxide thus formed had a breakdown voltage of about 2 volts and proved to be an electrical resistive film.
  • An electrically resistive barrier film was also formed on silicon by the process of this invention.
  • this barrier film a single silicon crystal was used and the silicon oxide was formed on one of its faces.
  • the apparatus of FIG. 1 was used and an anodizing electrode was brought into contact with the surface of the silicon crystal.
  • the oxygen pressure within the bell jar was maintained at 50 microns and after the priming layer of silicon oxide was formed the required electrical potential was applied to generate an oxygen ion-containing plasma, and the external electrical current to the anodizing electrode was started at 2 volts.
  • this externally applied voltage was increased by increments of between 2 and 3 volts. Such stepwise voltage increases were continued until the voltage across the resistive barrier film of silicon oxide reached 12 volts. This required about 20 minutes.
  • an electrically resistive barrier film was formed on a semiconductor material.
  • the ability to form an insulation layer of silicon oxide on a silicon body by the method disclosed herein is an important improvement over the present method of heating the silicon body at high temperatures for an extended period of time.
  • the sili con oxide is formed at room temperature in a relatively short time and within a vacuum system in which other steps in the construction of an integrated circuit may be accomplished.
  • the resistive barrier layer which is to serve as insulation between gate 50 and control 51 should preferably extend only over the crossover area 52 or just beyond it, leaving sufiicient surface areas on the gate 50 to electrically connect leads 53 which in turn may lead to soldering points 54.
  • a stencil 56 FIG.
  • a film of aluminum was deposited on a glass slide by vacuum deposition.
  • a stencil in which a pattern (including very fine lines) had been cut out was placed adjacent the aluminum film surface and after a priming layer had been formed on the film, the stencil-covered film was exposed to an oxygen plasma (50 microns pressure) for 30 minutes.
  • Samples were made with and without the use of an anodizing electrode. Examination of all of the samples showed that the aluminum oxide electrical resistive barrier layer grew only in those areas of the aluminum film where the pattern was cut through the stencil exposing the film. Sharp lines off-demarcation defining the patterns were observed by means of an ellipsometer, an instrument described in the literature.
  • a stencil may also be used in a manner to build up low resistance contact areas on the electrically conducting film prior to the formation of the electrically resistive barrier films in areas where they are required. Then, in the subsequent formation of the barrier films the stencil or mask need not be used.
  • a cryotron in which aluminum is to be used as the gate element and lead as the control.
  • a film of aluminum is deposited on a substrate in a pattern which consists of a strip having circular contact areas at each end.
  • a stencil which covers the strip and exposes the circular areas is then placed adjacent the substrate and a low resistance metal film which is not subject to any appreciable anodization, e.g., gold or tin, is deposited on the exposed circular areas.
  • the method of this invention provides the possibility of forming improved barrier films in greater variety. It also provides for forming improved circuit elements.
  • a method of forming an electrically resistive barrier film of controlled thickness comprising the steps of (a) forming on the surface of an electrically conducting body of anodizable material a thin priming layer of the resistive barrier film to be formed, said priming layer being the product resulting from a chemical reaction between said body and a gaseous reactant;
  • a method in accordance with claim 1 including the step of placing a stencil adjacent to the surface of said electrically conducting body whereby said electrically resistive barrier is formed on said body in a pattern.
  • a method in accordance with claim 1 further characterized by the additional steps of (d) increasing said electrical potential to a higher level;
  • step (e) repeating step (d) until an electrical resistive barrier film of a desired thickness is formed.
  • a method in accordance with claim 1 including the step of encapsulating at least said resistive barrier film thereby to prevent any appreciable change in the properties of said film.
  • a method in accordance with claim 1 including the step of controlling the water vapor content of said atmosphere.
  • a method of forming an electronic circuit element incorporating an aluminum oxide film on an aluminum surface comprising the steps of (a) depositing an aluminum film on an electrically nonconducting substrate;
  • a method of forming a silicon oxide film on a silicon surface comprising the steps of (a) exposing the surface of a silicon body to a gaseous atmosphere containing oxygen thereby to form on said silicon surface a priming coat of silicon oxide;

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US654009A 1962-09-20 1967-07-17 Method of anodizing by applying a positive potential to a body immersed in a plasma Expired - Lifetime US3394066A (en)

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NL298098D NL298098A (enrdf_load_stackoverflow) 1962-09-20
GB1052029D GB1052029A (enrdf_load_stackoverflow) 1962-09-20
FR947995A FR1375295A (fr) 1962-09-20 1963-09-19 Procédé pour réaliser une couche d'arrêt électriquement résistive
DE19631521815 DE1521815A1 (de) 1962-09-20 1963-09-20 Verfahren zum Herstellen einer elektrischen Sperrschicht
US654009A US3394066A (en) 1962-09-20 1967-07-17 Method of anodizing by applying a positive potential to a body immersed in a plasma

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Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3436327A (en) * 1966-07-18 1969-04-01 Collins Radio Co Selective sputtering rate circuit forming process
US3658672A (en) * 1970-12-01 1972-04-25 Rca Corp Method of detecting the completion of plasma anodization of a metal on a semiconductor body
US3673071A (en) * 1968-08-08 1972-06-27 Texas Instruments Inc Process for preparation of tunneling barriers
US3863074A (en) * 1972-08-30 1975-01-28 Ibm Low temperature plasma anodization apparatus
US3957608A (en) * 1974-01-15 1976-05-18 Cockerill-Ougree-Providence Et Esperance-Longdoz, En Abrege "Cockerill" Process for the surface oxidisation of aluminum
US3962988A (en) * 1973-03-05 1976-06-15 Yoichi Murayama, Nippon Electric Varian Ltd. Ion-plating apparatus having an h.f. electrode for providing an h.f. glow discharge region
US4091145A (en) * 1975-01-23 1978-05-23 Ricoh Co., Ltd. Support for electrophotographic sensitive plate
EP0010138A1 (en) * 1978-09-25 1980-04-30 International Business Machines Corporation A method of treating aluminium microcircuits
EP0039406A3 (en) * 1980-05-07 1982-04-28 International Business Machines Corporation Process and apparatus for plasma oxidizing substrates
FR2648478A1 (fr) * 1989-06-15 1990-12-21 Siderurgie Fse Inst Rech Procede de coloration de la surface de materiaux metalliques et produits obtenus par sa mise en oeuvre
US5391281A (en) * 1993-04-09 1995-02-21 Materials Research Corp. Plasma shaping plug for control of sputter etching
WO1997019203A1 (de) * 1995-11-22 1997-05-29 Balzers Aktiengesellschaft Verfahren zur plasma-thermochemischen oberflächenbehandlung, anlage hierfür sowie verwendungen des verfahrens bzw. der anlage
US5785838A (en) * 1993-02-26 1998-07-28 Nikon Corporation By Hiroyuki Sugimura Method for producing an oxide film
US20070194245A1 (en) * 2004-02-04 2007-08-23 Veeco Instruments Inc. Ion sources and methods for generating an ion beam with a controllable ion current density distribution
US20080179284A1 (en) * 2004-02-04 2008-07-31 Veeco Instruments Inc. Methods of operating an electromagnet of an ion source
US10077717B2 (en) 2014-10-01 2018-09-18 Rolls-Royce Corporation Corrosion and abrasion resistant coating

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US2346483A (en) * 1942-08-07 1944-04-11 Gen Electric Chargeproof cover glass
US3035205A (en) * 1950-08-03 1962-05-15 Berghaus Elektrophysik Anst Method and apparatus for controlling gas discharges
US2955998A (en) * 1953-02-17 1960-10-11 Berghaus Bernhard Process for carrying out technical operations in a glow discharge
US3077444A (en) * 1956-06-13 1963-02-12 Siegfried R Hoh Laminated magnetic materials and methods
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Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3436327A (en) * 1966-07-18 1969-04-01 Collins Radio Co Selective sputtering rate circuit forming process
US3673071A (en) * 1968-08-08 1972-06-27 Texas Instruments Inc Process for preparation of tunneling barriers
US3658672A (en) * 1970-12-01 1972-04-25 Rca Corp Method of detecting the completion of plasma anodization of a metal on a semiconductor body
US3863074A (en) * 1972-08-30 1975-01-28 Ibm Low temperature plasma anodization apparatus
US3962988A (en) * 1973-03-05 1976-06-15 Yoichi Murayama, Nippon Electric Varian Ltd. Ion-plating apparatus having an h.f. electrode for providing an h.f. glow discharge region
US3957608A (en) * 1974-01-15 1976-05-18 Cockerill-Ougree-Providence Et Esperance-Longdoz, En Abrege "Cockerill" Process for the surface oxidisation of aluminum
US4091145A (en) * 1975-01-23 1978-05-23 Ricoh Co., Ltd. Support for electrophotographic sensitive plate
EP0010138A1 (en) * 1978-09-25 1980-04-30 International Business Machines Corporation A method of treating aluminium microcircuits
EP0039406A3 (en) * 1980-05-07 1982-04-28 International Business Machines Corporation Process and apparatus for plasma oxidizing substrates
FR2648478A1 (fr) * 1989-06-15 1990-12-21 Siderurgie Fse Inst Rech Procede de coloration de la surface de materiaux metalliques et produits obtenus par sa mise en oeuvre
US5785838A (en) * 1993-02-26 1998-07-28 Nikon Corporation By Hiroyuki Sugimura Method for producing an oxide film
US5391281A (en) * 1993-04-09 1995-02-21 Materials Research Corp. Plasma shaping plug for control of sputter etching
WO1997019203A1 (de) * 1995-11-22 1997-05-29 Balzers Aktiengesellschaft Verfahren zur plasma-thermochemischen oberflächenbehandlung, anlage hierfür sowie verwendungen des verfahrens bzw. der anlage
US20070194245A1 (en) * 2004-02-04 2007-08-23 Veeco Instruments Inc. Ion sources and methods for generating an ion beam with a controllable ion current density distribution
US20080179284A1 (en) * 2004-02-04 2008-07-31 Veeco Instruments Inc. Methods of operating an electromagnet of an ion source
US7557362B2 (en) 2004-02-04 2009-07-07 Veeco Instruments Inc. Ion sources and methods for generating an ion beam with a controllable ion current density distribution
US8158016B2 (en) 2004-02-04 2012-04-17 Veeco Instruments, Inc. Methods of operating an electromagnet of an ion source
US10077717B2 (en) 2014-10-01 2018-09-18 Rolls-Royce Corporation Corrosion and abrasion resistant coating

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