Classifications

• • 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
  • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
  • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
  • H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
  • H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
  • H01L21/302—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to change their surface-physical characteristics or shape, e.g. etching, polishing, cutting
  • H01L21/306—Chemical or electrical treatment, e.g. electrolytic etching
  • H01L21/3065—Plasma etching; Reactive-ion etching
• • 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
  • C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
  • C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
  • C23C16/448—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating characterised by the method used for generating reactive gas streams, e.g. by evaporation or sublimation of precursor materials
  • C23C16/452—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating characterised by the method used for generating reactive gas streams, e.g. by evaporation or sublimation of precursor materials by activating reactive gas streams before their introduction into the reaction chamber, e.g. by ionisation or addition of reactive species
• • 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

Definitions

• the present invention relates to a method of surface treatment, in particular of hard body surfaces and sensitive media. It also relates to a device for implementing the method
• the method and the device according to the invention can be used in particular in electrical engineering, electronics, chemistry, the food industry, macro-tools, medicine, pharmaceuticals, in particular to carry out cleaning and sterilization operations. , pickling, film deposition, surface alloys, etc.
• a process for the treatment of solid surfaces by vacuum plasma is known, during which a flow of active particles is formed at low pressure. This process is described in the document "The ionoplasmic treatment of materials", Ivanovskn GF and Petrov VI, Moscow 1986 This flow of particles acts on the surface of the solid body and the volatile products resulting from the interaction of the plasma are removed from the reaction zone.
• the plasma composition is chosen according to the destination of the treatment. To increase the efficiency of the vacuum plasma operation, the kinetic energy of the particles is increased to 100 eV and more, which causes the appearance of defects due to destructive bombardments of the treated surface structure.
• This treatment which requires maintaining the vacuum, is preferably used where the surfaces to be treated are of limited dimensions, in particular in the electronic industry.
• DPO Dynamic Plasma Operation
• the interaction of the plasma with the surface can only be momentary and does not exceed 10 ms.
• the treated object passes through the plasma flow at a controlled speed ( ⁇ 1 m / s) in such a way that in non-stationary thermal conduction conditions the maximum surface temperature does not exceed a given limit.
• this temperature level can be several tens of degrees or even several hundred degrees.
• the DPO treatment Since the duration of the DPO treatment is shorter than the characteristic diffusion time in the solid body, the DPO treatment does not cause defects in the structure of the solid body treated.
• the main physical energy of the DPO method is expressed by the two inequalities
• l r is the average length of the free path of the plasma particles
• d the thickness of the boundary layer at the critical point
• l ⁇ n the average length of diffusion of the active particles of the plasma.
• the DPO method is easy to use, especially at atmospheric pressure.
• the change to atmospheric pressure increases the productivity of the treatment from 10 to 100 times, compared to the vacuum plasma process.
• the quality of the treatment is superior and the technology simplified
• the DPO method can only be used under the following conditions
• the treatment is done by a high enthalpy plasma jet.
• the aim of the present invention is to widen the choice of treatable materials, to make possible new ones. surface treatments thanks to the separate control of activated and modifying flow thermal functions and also to enlarge the ranges of the physical parameters of the flows used for the treatment.
• the present invention relates to a method of surface treatment, in particular of surfaces of hard bodies and of condensed media, during which one or more fluxes of active particles are created, they are directed onto the surface to be treated and interact the flow of particles with the surface, and in which the flow (s) of active particles is (are) composed of activated particles, forming chemically active centers on the surface, and of modifying particles occupying these centers, the energy of activated particles being greater than the rupture energy of the inhibited surface bonds of the treated surface and less than the energy of formation of the radiative defects on the surface, the intensity, at the level of the treated surface, of the flux of the activated particles and of the flux of modifying particles being greater than the quantity N / t where N is the surface density of the inhibited bonds to break, and t is the time of presence of a po any int of the treated surface, under the flux.
• the invention also relates to a surface treatment device for implementing the method, comprising a device for introducing the active product of a flow generator of active particles containing an energy source, a reactor creating the flow of active particles, a silver for transporting the active particles generated at the treated surface and an agent for removing the residual products from the treatment, and in which the active particle generator comprises.
• a device for relative displacement of the treated surface with respect to the fluxes of activated and modifying particles ensuring that the period of time between the actions of activating and modifying the same area of the treated surface is less than the time of life of the activated centers created by the activated particles and that the areas of the surface to be treated are first in contact with the flow of activated particles and then only with the flow of modifying particles,
• the activated particles coincide with the modifying particles, which makes it possible to reduce the generator device to an introduction device, a reactor, a transport device, a device for relative displacement of the surface, and an evacuation device.
• the reactor, the transport and evacuation devices may be common for the activated particles and the modifying particles.
• the evacuation device can be common for the activated particles and for the residual products.
• FIG. 1 is a general diagram illustrating the process
• FIG. 2 is a first embodiment of the device according to the invention. the marks relative to the figure
• Diterbutil vapor heaters ((H3 C) 3 C Mg C (0.3) 3) diluted in a neutral gas flow (Ar). Heating temperature: 1000 K
• Distribution tube transport of the modifying particles fig
• FIG. 3 is a second embodiment of the device according to the invention. the marks relative to the figure
• FIG. 4 is a third embodiment of the device according to the invention.
• the references relating to FIG. 4 are as follows:
• Reactor used to heat and activate the oxygen and nitrogen molecules in the air at T ⁇ 1000 K 2 Nozzle forming the jet of excited air and directing it towards the surface of iridium
• Ventilation device for removing residual products
• the solution consists in creating one or more particles flows, in directing them towards the treated surface, in making these particles interact with the surface, so that, according to the invention.
• the flow of activated particles is formed of particles which, once activated by the plasma, form active chemical centers on the surface,
• the energy of the activated particles is greater than the energy of rupture of the inhibited bonds of the treated surface and smaller than the energy of formation of the radiative defects
• N is the surface density of the inhibited bonds of the treated surface and t the time of presence of a point on the treated surface under the flux.
• the essence of the invention consists in that, unlike the DPO method, one or more fluxes are created containing specially chosen particles, some activated, the other modifiers, whose functions are different:
• the role of the flow of activated particles is to transfer the treated surface into an activated state, that is to say to create chemically active centers by breaking the inhibited surface bonds, for example
• the activated particles In order for the activated particles to play their role, their energy E a must be greater than the breaking energy of the mnibé link.
• the energy E a must on the other hand be smaller than the energy of formation of the radiative defects in order to preserve the quality and the structure of the surface layer of the body treated.
• the intensity of the flow of the activated particles falling, the treated surface must be greater than the quantity N / t where N is the surface density of the inhibited bonds to break, and t the duration of presence of any point of the treated surface under the flow.
• the quantity N can be less than the total number of inhibited bonds of the treated surface in the case where the desired treatment does not import the rupture of all the inhibited bonds of the surface.
• the role of the flux of modifying particles is to occupy the chemically active centers, result of the impact of the activated particles, that is to say to use the activated state of the surface, created by the activated particles to efficiently operate the desired treatment, such as depositing films (with optimal chemical adhesion), pickling (with the formation of volatile, chemically solid molecules), etc.
• the processes of formation and binding of the chemically active centers of the treated surface can be developed in parallel.
• the modifying particles can be used in an activated state.
• the intensity of the flux of the modifying particles on the treated surface is chosen which is greater than the quantity N / t, so as to use all the activated centers created by the activated particles. In this case the treatment is optimal.
• the activated and modifying particles can coincide, being of the same chemical nature.
• the physico-chemical mechanism of surface treatment therefore consists of the following.
• the atoms on the surface acquire chemical properties which may have been obtained for example by suddenly removing a surface layer of macroscopic thickness from the material to be treated. It is this layer which, under usual conditions, prevents the appearance of chemical activity on the surface.
• the effect of the action of the activated particles is to create chemically active centers on the surface (radicals).
• the modifying particles bind to these centers, which makes it possible to carry out the desired surface treatment effectively. Since the activation state of the surface has a limited lifetime, the bonding process with these centers must be carried out in a shorter time than this lifetime.
• the particles can be activated by different means, not necessarily by the heating of the gas they form up to the temperature of (10 to 15) -10 3 K and the formation of a plasma, as is the case. in the DPO method.
• the activation of the particles and the heating of the gas which they form are entirely separate and independent processes. It is therefore possible to control the heating, that is to say the thermal function of the flux, separately, according to the requirements imposed on the desired treatment.
• the particles can be activated, for example by radiation or as a result of collisions with a flow of charged particles, accelerated in an electromagnetic field. It is also possible to control the fluxes of activated and modifying particles by rapidly decreasing or increasing the pressure of the gas they form.
• the field of physical parameters of the flux acting on the treated surface can therefore be greatly enlarged and enriched.
• the density of the flow of particles falling on the treated surface must be large enough, otherwise the activated centers can spontaneously relax, that is, return to their initial state before modifying particles have fixed them.
• the second way is to increase the density of the particles in the stream. An increase in density leads to the transition from flux, which goes from molecular to viscous flux. In this case, between the falling flux and the treated surface forms a boundary layer, the thickness of which can be varied to vary the intensity of the desired treatment.
• the boundary layer plays a triple role in the present invention.
• the boundary layer is a useful obstacle against the return and redeposition on the treated surface of the residual molecules, resulting from the surface treatment (for example, during pickling).
• the boundary layer can play an active role, generating activated particles.
• the hydrodynamic parameters of the flow are chosen so as to satisfy the inequality: d x ⁇ 6D t ⁇ n
• d] _ is the distance from the treated surface to the generation area of the activated particles.
• the present invention makes it possible to carry out, in addition to the technologies known and produced by the DPO method, technologies not yet carried out: bonding or welding at the molecular level of pairs of uniform or heterogeneous materials, bondable or msoudable with one another by known methods, the treatment of non-regular organic polycondensates, in particular natural polycondensates, which is obtained by separately controlling the activating and modifying thermal functions of the flux and by widening the range of physical parameters of the flux used for the treatment.
• the present invention can be used in particular for disinfection and sterilization of surfaces, for film deposition operations, pickling, cleaning, surface alloys in the semiconductor industry, to make surfaces bactericidal, create coatings for various uses, etc.
• the flow of activated particles is formed of activated particles creating chemically active centers on the surface and the flow of particles modifying particles occupy these centers,
• the intensity at the treated surface of the flow of activated particles, as well as of modifying particles is greater than the quantity N / t where N is the surface density of the inhibited bonds to break and t the duration of presence of a point any of the surface treated under the flux.
• the method of the present invention and its implementation device can be carried out on equipment of different types. Since this process makes it possible to carry out very diverse surface treatments, only the essential parts necessary for any equipment for carrying out the invention will be cited. - a generator of flow of activated particles, a generator of flow of particles modifiers (the two generators, in certain particular cases being able to be reduced to only one), devices for making contact of the particle flows with the treated surface, transport devices ensuring the relative movement of the treated surface and the flows activators and modifiers, devices for removing residual products from the process.
• the general scheme of the process is shown in Figure 1.
• the energy of the inhibited bonds is equal to 4 eV, the surface density of these bonds being 10 15 cm 2 , the part of the surface bonds to be broken being 10%.
• the duration of the treatment does not must not exceed 10 ⁇ 3 s. So the density of the flow of activated particles must not be less than 10 17 cm -2 s -1 .
• activated particles we choose the excited molecules of nitrogen N2 (B 3 fig, A 3 ⁇ + a , a ⁇ " u , with activation energies within the limits of 6 to
• magnesium atoms obtained thanks to the thermal decomposition of ditertbutil vapors ((H3 C) 3 C Mg C (01.3) 3) diluted in a neutral gas flow, heated to 1000 K.
• the density of the flux of modifying particles must be greater than 10 17 cm -2 s -1 .
• the energy of the inhibited bonds of silicon is approximately 1 eV, - the total surface density of these bonds is approximately ÎO 1 ⁇ cm " 2 , the part of the surface bonds to be broken is 100%.
• the time t of presence under the flux for an atomic layer must be approximately 3-10 -3 s. So the flow of activated particles must not be less than 3-10 ⁇ - 8 cm “2 s" 1 .
• activated particles we choose fluorine atoms, obtained thermally thanks to the decomposition of carbon tetrafluoride (CF 4 ) in the flow of gas heated to more than 2000 K.
• the energy of activation in this case is l affinity energy of electrons to fluorine atoms and is 3.4 eV.
• modifying particles fluorine atoms are also used. In this example the activated and modifying particles coincide.
• the energy of the inhibited bonds is equal to 0.1 eV, the total surface density of these bonds being 3-10 15 cm “2 , the part of the surface bonds to be broken being 100%.
• the time t is order of 10 ⁇ 2 s.
• the flux of the activated particles must not be less than 3.10 : L7 cm “2 s " *.
• the oxygen and nitrogen molecules of the heated air are chosen.
• the activation energy in this case is the thermal energy of the molecules.
• oxygen molecules are used.
• the flux of modifying particles cannot be less than 3 • 10 17 cm " 2 s -1 . In this example, the actual flux of activated particles, given the use of air, greatly exceeds the limit requirements of the method.
• the method according to the invention makes it possible to widen the areas of use of the DPO method, and in particular to create new treatment methods, such as for example the formation of solidifying metallic layers on the polymers, while reducing energy costs, thanks in particular to the decrease in the processing temperature.
• the corresponding device is illustrated in Figure 4.

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• 1996
  • 1996-11-12 WO PCT/CH1996/000400 patent/WO1997018344A1/fr not_active Application Discontinuation
  • 1996-11-12 US US09/068,695 patent/US6365235B2/en not_active Expired - Fee Related
  • 1996-11-12 EP EP96934312A patent/EP0861338A1/de not_active Withdrawn

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