FR2579486A1 - METHOD FOR ADJUSTING THE SPEED OF FINE PARTICLES - Google Patents

Abstract

THE INVENTION RELATES TO A METHOD FOR ADJUSTING THE SPEED OF FINE PARTICLES BY MEANS OF A TUBE. IT CONSISTS OF PLACING A CONVERGENT-DIVERGENT PIPE 1 IN THE FLOW PATH OF THE FINE PARTICLES BETWEEN AN UPSTREAM CHAMBER 3 AND A DOWNSTREAM CHAMBER 4 IN EACH OF WHICH A VACUUM IS ESTABLISHED BY MEANS OF A PUMP 5, AND GIVE THE PP REPORT FROM A PRESSURE P GOING FROM A DOWNSTREAM SIDE TO A PRESSURE P FROM AN UPPER SIDE, A VALUE AT OR LESS THAN A CRITICAL PRESSURE RATIO. FIELD OF APPLICATION: PROJECTION OF FINE AND ULTRA-FINE PARTICLES TO FORM FILMS, FILMS, COMPOSITE MATERIALS, TO MAKE DOPING, ETC.

Description

The invention relates to a method for controlling particle velocity

  fines, used for the transport or projection of fine particles and which can be adapted to the formation of a film or film, the formation of a composite material, doping, etc., with the aid of fine particles , or to a field of training

fine particles.

  As used herein, fine particles include atoms, molecules, ultra-fine particles, and general fine particles. The

  ultra-fine particles are those generally

  0,5 ppm, obtained, for example, by gas evaporation, plasma evaporation, chemical vapor reaction, colloidal precipitation in a liquid or pyrolysis of a spray of

  liquid. The general fine particles are the

  fines obtained by normal processes such as

  mechanical grinding, crystallization or precipitation.

  A beam is a flow or flow of trans-

  substantially constant in the direction of flow, regardless of the geometry of this

cross section.

  Fine particles are usually dispersed

  and suspended in a carrier gas and are

  transported by the flow of this carrier gas.

  Conventionally, the regulation or regulation of the speed of the fine particles during their transport is simply obtained by a definition of the entire flow of the fine particles flowing with the carrier gas, by means of a pipe or an envelope and, in addition, by adjusting the pressure difference between

the upstream and downstream sides.

  In the case of the projection of fine particles onto a substrate, the particles are generally ejected from a nozzle with the carrier gas. The nozzle used in such a projection of fine particles is a straight or convergent nozzle, and the adjustment of the speed of the ejected fine particles is simply achieved by adjusting the difference between the pressures prevailing before and behind the nozzle. However, with the conventional speed setting simply relying on the pressure difference, it is difficult to predict the speed setting of the entire flow of fine particles as this flow becomes dispersed with a wider density distribution. . Furthermore, in the case of flow control based solely on the pressure difference, no fine adjustment of the speed of the fine particles can be expected because the amplitude of the pressure difference is not always in direct relationship with the amplitude of the speed. The speed depends rather on a factor other than the pressure difference. If the speed of the fine particles can not be exactly adjusted, for example, the fine particles are deactivated by a delay in the transport and formation of the film, etc., by projection of the fine particles is then easily inhibited by kinetic energy. excessive or insufficient

fine particles ejected.

  The present invention is intended to solve

the problems described above.

  More particularly, an object of the invention is to propose a new method for adjusting the speed

fine particles.

  The object mentioned above can be realized

  according to the invention as described below.

  According to one aspect of the invention, there is provided a method for controlling the rate of fine particles, comprising placing a convergent-divergent nozzle on the flow path of said fine particles, and carrying a pressure ratio P / P0 a pressure P prevailing on the downstream side at a prevailing P0 pressure of the upstream side, to

  a critical value or below this value.

  According to another aspect of the invention there is provided a method for controlling the rate of fine particles, of placing a convergent-divergent nozzle on the flow path of said fine particles, to carry a P / P ratio of pressure P reigning from a downstream side to a pressure P prevailing from an upstream side to a value o

  critical or below this value, and to choose

  the ratio of the area of the section of an opening

to that of a throat of the nozzle.

  According to another object of the invention,

  a method is proposed for adjusting the speed of

  thin layers, consisting of placing a convergent nozzle

  divergence in the flow path of the fine particles, and to bring the ratio P / P0 of a pressure P prevailing of a

  downstream at a pressure P prevailing from an upstream side to-

o

above a critical value.

  According to another aspect of the invention,

  a method is proposed for adjusting the speed of

  thin layers, consisting of placing a convergent nozzle

  diverging in the flow path of said fine particles, to bring the P / P ratio of a prevailing pressure P

  downstream side at a prevailing pressure P0 from the upstream side to

  above a critical value, and to properly choose the ratio of the area of the section of an opening to that

a throat of the nozzle.

  The invention will be described in more detail with reference to the appended drawings by way of non-limiting examples and in which: FIG. 1 is a schematic view showing the basic principle of the present invention; FIG. 2 is a diagrammatic view, partly in section, of a film-forming apparatus, using ultra-fine particles according to the invention; FIGS. 3A to 3C are partial perspective views, with tearing away; partially, of several embodiments of gas excitation means; FIGS. 4A to 4D are, respectively, longitudinal sections and a perspective view of convergent-divergent nozzle shapes; and - Figure 5 is a schematic view in

perspective of a diaphragm.

  Figure I is a schematic view showing

  the fundamental principle of the present invention, that is,

  of a method for controlling the rate of fine particles, of placing a convergent-divergent nozzle in the flow path of the fine particles and giving the P / P0 ratio of a pressure P prevailing from a downstream side to a pressure P0 prevailing on an upstream side a value greater than or not exceeding a critical pressure ratio. A convergent-divergent nozzle 1 used in the present invention has an opening cross-section which, as shown in FIG.

  progressively from an entrance to an

  mediator 2, then gradually widens towards an exit

  lb. For ease of description, in Figure 1, the entrance

  and the outlet of the convergent-divergent nozzle I are respectively connected to a closed upstream chamber 3 and a closed downstream chamber 4. However, the inlet and the outlet of the convergent-divergent nozzle I according to the invention can be connected to closed or open circuits provided that the fine particles are circulated in the nozzle with a carrier gas, by a difference of

  pressure between the inlet and the outlet.

  In the present invention, an optimum state of expansion means that the pressure P1 at the outlet 1b of the nozzle is equal to the pressure P prevailing in the downstream chamber 4, so that the outflow from the

  nozzle has the characteristic of a beam.

  In a state of -sous-détente P> P, the

  Ejected fluid or fluid diverges rapidly outwardly from the outlet of the nozzle, which does not allow to obtain a uniform flow. Furthermore, in a state of over-expansion P1 <P, the flow or flow may have a detachment inside the nozzle, thus becoming unstable and it also tends to produce a

  shock wave and is not suitable for the present purposes.

  To achieve optimum expansion flow, pressure sensors are provided at or around the outlet of the nozzle and the downstream chamber, respectively, and the pressures P at the upstream portion and P at the downstream portion are adjusted so that the pressures detected by the sensors can be approximately equal to each other. In the present invention, a pressure difference between the upstream chamber 3 and the downstream chamber 4

  is established, as shown in Figure 1, by the food

  the upstream chamber 3 into a carrier gas in which the fine particles are dispersed in a state of suspension, and by the evacuation of the downstream chamber 4 by means of a vacuum pump 5 so that the carrier gas supplied , containing the fine particles, flows from the upstream chamber 3 to the downstream chamber 4 through the convergent-divergent nozzle. The convergent-divergent nozzle I serves not only to eject the fine particles with the carrier gas, depending on the pressure difference between the upstream and downstream sides, but also

  make uniform the ejected flow of carrier gas and parti-

  fine cules. This uniform flow or flow of fine particles can result in easy adjustment of the

  speed of the entire flow.

  The convergent-divergent nozzle 1 is capable of controlling the speed of the fine particles ejected with the carrier gas, by a suitable choice of a P / P ratio of the pressure P prevailing in the downstream chamber 4 to the pressure P 0 prevailing in the upstream chamber, and a ratio A / A * of the cross-sectional area of the opening A of the outlet lb to that A * of the groove 2. If the ratio P / P0 of the pressures prevailing in the chambers upstream and downstream 3, 4 is greater than a critical pressure ratio, the flow rate at the outlet of the nozzle i becomes subsonic or less, and the fine particles and the carrier gas are ejected at a reduced speed. On the other hand, if the pressure ratio P / P. is equal to or less than the critical pressure ratio, the outlet flow velocity becomes supersonic, so that fine particles and the carrier gas are ejected

at a supersonic speed.

  Assuming that the flow of the fine particles is a one-dimensional compressive flow with adiabatic expansion, the Mach number M that can be reached by this flow is determined by the pressure P of the upstream chamber and the pressure P of the downstream chamber. , o according to the formula: yl

M U [() Y-1] 2 (1)

  where u is the speed of the flow of

  fine cules, a is the local acoustic velocity at this point, and y is the ratio of the specific heats of the fluid; M exceeds I when the ratio P / Po is equal to the critical pressure ratio, or less, and M is less than 1 when the ratio P / Po is greater than the critical ratio

pressure.

  The acoustic velocity can be determined by the formula: a = vYRT where T is the local temperature and R is the gas constant. There is also the following relationship between the opening transverse sections A, A * of the outlet 1b of the groove 2 and the Mach number M: A _ ir (2 1, y -i1.2) 2 (y + 1 )

A * M + + M (2)

  It is therefore possible to regulate the speed of the flow of the fine particles ejected from the nozzle I by choosing the opening ratio A / A * as a function of the Mach M number determined by the equation (1) from the ratio pressure P / P0 of the upstream and downstream chambers, or by regulating the ratio P / P0 as a function of the value M

  determined by equation (2) from the opening report

  A / A *. The velocity u of the flow of the fine particles can be determined by the following equation (3): M) 1

/ 7 =, (1 + I .-! 2- M) (3)

  in which T represents the temperature of the chamber

upstream 3.

  When the ratio P / Po is greater than the critical value or critical pressure ratio, the speed of the fine particles rises to the number of Mach M according to the preceding formula (1), in the groove 2 of the convergent nozzle. divergent 1. Then, the flow of

  Fine particles are ejected from the nozzle while slowing down.

  The mode of slowing down between the passage in the groove 2 and the ejection varies according to the ratio A / A * of the area of the opening section A of the output lb to that A * of the groove 2. Consequently, the speed of fine particles ejected with the carrier gas can be adjusted by adjusting the A / A ratio * below a subsonic state. In addition, the flow of fine particles can be achieved under

the shape of a beam.

  TO In the ejection of fine particles to the ratio P / Po above the critical pressure ratio gas

  carrier and the fine particles then constitute a listening

  distributed uniformly. Although the flow is diffused, the density distribution of the fine particles is uniform and the degree of diffusion can be regulated by the ratio A / A * of the areas of the opening sections in the convergent-divergent nozzle I. Therefore, fine particles having a desired degree of diffusion can be

  transported in the downstream chamber 4, in a spatial state-

  independently and the speed of fine particles can

  therefore be set accurately.

  On the other hand, the carrier gas and fine particles, if ejected in one direction in the form of a high velocity flow when the P / P0 ratio is equal to or less than the critical pressure ratio.

  to this report, constitute a beam, retaining

  its cross-section immediately after ejection.

  As a result, the fine particles transported by the carrier gas also constitute a beam which is transported at a high speed in the downstream chamber 4,

  with minimal diffusion and spatially

  With the walls of the downstream chamber 4, the exit velocity of the particles can be precisely adjusted. It has therefore become possible to capture active fine particles on the substrate 6 placed in the downstream chamber 4 in a satisfactory active state, by generating said active fine particles in the upstream chamber 3 and transporting them with the aid of the nozzle 1 , or by generating the active fine particles in or immediately after the nozzle I and transporting them, in the form of a spatially independent beam, while regulating

  the speed of the fine particles to a supersonic state.

  In addition, the kinetic energy of fine particles

  they are projected can be easily regulated because the fine particles are projected onto the substrate 6 in the form of a beam whose speed is set. In a subsonic state too, similar results can be obtained. FIG. 2 schematically shows an embodiment of the invention applied to an apparatus for

  film or film formation with the help of

  ultra-thin cells, this figure illustrating a convergentdispersion nozzle 1, an upstream chamber 3, a first

  downstream chamber 4a and a second downstream chamber 4b.

  The upstream chamber 3 and the first downstream chamber 4a are made of a single block and are connected by

  detachably, at the first downstream chamber 4a, a dia-

  7, a valve 8 and the second downstream chamber 4b which are similarly formed in a single block structure, the connection being effected by means of flanges of a common diameter, which will be called hereinafter common flanges . The upstream chamber 3, the first downstream chamber 4a and the second downstream chamber 4b are held at higher and higher degrees of vacuum by a vacuum circuit described below. It is connected, by means of a common flange, to one side of the upstream chamber 3, gas excitation means 9 which generate active ultrafine particles, by plasma, and direct the particles towards the convergent nozzle. divergent I which faces them, at the same time as a carrier gas such as hydrogen) helium, argon or nitrogen. The inner walls of the

  upstream chamber 3 may receive anti-

  adherent to pocket the ultrafine particles thus produced adhere to said inner walls. Due to the pressure difference between the upstream chamber 3 and the first downstream chamber 4a due to the higher vacuum in the latter, the ultra-fine particles produced flow, with the carrier gas, through the nozzle I to the

first downstream chamber 4a.

  As shown in FIG. 3A, the gas excitation device 9 comprises a first bar-shaped electrode 9a housed in a second tubular electrode 9b in which the carrier gas and the material

  first gas are introduced, and an electric discharge

  It is induced between the electrodes 9a and 9b. The gas excitation device 9 may also be made as shown in FIG. 3B, with a first porous electrode 9a for the supply of carrier gas and of gaseous raw material to the space between the first and second electrodes, or, as shown

  in FIG. 3C, with a tube composed of semi-electrodes

  circular 9a, 9b, separated by insulators 9c and wherein the carrier gas and the gaseous raw material

are introduced.

  The convergent-divergent nozzle I is mounted by means of a common flange on a lateral end of the first downstream chamber 4a directed towards the upstream chamber 3 in order to enter the upstream chamber 3, the inlet being open in the upstream chamber. 3 and the output lb opened in the first downstream chamber 4a. The nozzle I may also be mounted so as to project into the first downstream chamber 4a. The direction in which the nozzle 1 exceeds depends on the size, the quantity and the quantity.

  of the nature of ultra-fine particles to be transported.

  As explained above, the cross section of the convergent-divergent nozzle 1 decreases progressively from the inlet 1a to the groove 2, then progressively widens towards the outlet 1b, and the derivative of the profile of the channel changes continuously and reaches zero at groove 2, thereby minimizing the formation of growth limit layers in the nozzle 1. In the present invention, the curve or curvature of the flow path in the

  nozzle 1 means the curve presented by the wall

  in a section along the axis of the direction of flow. It is thus possible, thus, to choose the useful cross section of the flow in the nozzle I so that it is close to the nominal value, and

  fully exploit the functional characteristics of

  As shown in the enlarged view of FIG. 4A, the inner periphery, close to the portion 1b, is advantageously substantially parallel to the central axis, or has a derivative equal to zero, in order to facilitate the formation of a flow or parallel flow,

  because the flow direction of the carrier gas and the

  The ejected fines are affected, to some degree, by the direction of the inner periphery near the exit 1b. However, if the angle X formed by the bottom wall, from the groove 2 to the outlet lb, with the axis

  central is chosen to be less than 7,

  5s or less as shown in FIG. 4B, it is possible to prevent the peeling phenomenon and to keep the carrier gas and the ejected ultrafine particles in a substantially uniform state. As a result, in

  In this case, the inner peripheral wall can be dispensed with.

  Parallel parallel mentioned above and the manufacture of the nozzle 1 can be facilitated by the removal of this parallel wall. In addition, ejection in the form of brush or slot, carrier gas and ultrafine particles,

  can be obtained by using a rectangular nozzle

  gullet I as shown in Figure 4C.

  The phenomenon of separation mentioned above

  above means the formation of an enlarged boundary layer between the inner wall of the nozzle I and the circulating fluid, due, for example, to the presence of a projection on the inner wall, giving rise to uneven flow and this phenomenon tends to occur more frequently when the flow velocity is greater. To prevent this phenomenon of separation, the angle c above is advantageously chosen to be smaller when the inner wall of the nozzle I has a less precise finish. The inner wall of the nozzle I must be finished to a precision indicated by three, and advantageously by four, triangular markers returned, as defined in JIS B 0601. As the peeling phenomenon in the divergent part of the nozzle I significantly affects the flow of carrier gas and ultrafine particles, the surface finish is important for said divergent portion, to facilitate the manufacture of the nozzle 1. In addition, to prevent the phenomenon of delamination, it is necessary to give the groove 2 a gentle curvature and to avoid the presence of an infinitely large derivative in the rate of variation of the

the cross section.

  Examples of material suitable for producing the convergent-divergent nozzle I include metals such as iron and stainless steel, plastics such as acrylic resin, polyvinyl chloride, polyethylene, polystyrene and polypropylene, ceramic materials, quartz, glass, etc. The material can be chosen taking into account the absence of reaction with the ultrafine particles to be produced, the ease of mechanical machining, the emission of gas in the vacuum circuit. In addition, the inner wall of the nozzle I may be plated or coated with a material preventing adhesion of or reaction with the particles.

  ultrafine. An example of such a material is a coating

  polyfluoroethylene. The length of the convergent divergent nozzle I can be arbitrarily set taking into account, for example, the length of the apparatus. Thermal energy is converted into kinetic energy as the gas passes

  Carrier and fine particles in the nozzle 1.

  In the case of a subsonic ejection, the thermal energy is significantly reduced to approach a supercooled state. Therefore, if the carrier gas contains condensable constituents, it is also possible to

  form the ultra-fine particles by condensing these

  by such supercooling. This process makes it possible to obtain homogeneous ultra-fine particles, because of the formation of homogeneous nucleation. In that case,

  also, the convergent-divergent nozzle I must preferably

  to be longer to obtain a condensa-

  sufficient. On the other hand, this condensation increases the thermal energy and reduces the kinetic energy. As a result, to maintain high speed ejection,

  the nozzle I must be advantageously shortened.

  At the passage of the carrier gas flow, containing ultrafine particles, in the aforementioned convergent-divergent nozzle 1, with an appropriate choice of the P / Po ratio of the pressures prevailing in the upstream chamber 3 and in the downstream chamber 4, and the ratio A / A * of the openings of the groove 2 and the outlet 1b, the flow velocity is set, the flow taking place at a speed determined by the pressure ratio and the ratio of the areas of opening of the first downstream chamber 4a to the second downstream chamber 4b. In particular, when the P / P ratio is equal to or less than the critical pressure ratio o, the flow of the carrier gas

  is established as a high-speed beam.

  The diaphragm 7 is a variable opening that can be adjusted externally so as to vary step by step the area of the opening between the first

  downstream chamber 4a and the second downstream chamber 4b for main-

  hold a higher degree of vacuum in the second chamber

  downstream 4b than in the first chamber 4a. More specifically

  The diaphragm is composed, as shown in FIG. 7A, of two adjustable plates 11, 11 'which respectively have notches 10, 10' and which are slidably mounted so that the notches 10, 10 'are mutually opposed. The adjustable plates or plates 11, 11 'can be moved from the outside,

  and the notches 10, 10 'cooperate to define an opening

  which allows the passage of the beam while being able to maintain a sufficient degree of vacuum in the second downstream chamber. In addition, the shape of the notches 10, diaphragm 7 and adjustable plates 11, 11 'is not limited to the V-shape shown above and shown in FIG. 5, but this shape may be semicircular.

Or other.

  The valve 8 comprises a shutter member 13 in the form of a barrier, open or closed by means of a handle 12, and it is completely open when the beam passes. By closing the valve 8, it is possible to replace the block of the second valve chamber 4b, while maintaining the vacuum in the upstream chamber 3 and in the first downstream chamber 4a. In the case where the ultrafine particles are easily oxidizable metal particles,

  it is possible to replace the block without risk of oxidation.

  quickly using a spherical or

  instead of valve 8 and replacing the

  second valve chamber 4b with the spherical valve.

  In the second downstream chamber 4b, it is

  placed a substrate 6 for picking up the ultrafine particles

  transported in the form of a beam, so that these particles form a film or film. The substrate is mounted on a substrate holder 16 at one end of a sliding rod 15 which is mounted in the second downstream chamber 4b by means of a common flange and which is displaced by a cylinder 14. It is provided in front of the substrate 6, a shutter] 7 intended to intercept the beam when necessary. The substrate holder 16 is furthermore capable of heating or cooling the substrate 6 to a state

  optimal for capturing ultra-fine particles.

  Glass windows 18 are mounted by means of common flanges, as illustrated, on the upper and lower walls of the upstream chamber 3 and the second downstream chamber 4b, so that it is possible to observe the interior. Although not illustrated, similar glass windows are mounted by means of common flanges on the front and rear walls of the upstream chamber 3, the

  first downstream chamber 4a and the second downstream chamber 4b.

  These glass windows, when removed, may be used for mounting various measuring instruments or a load chamber, using the

common flanges.

  Here will be described a vacuum circuit to

  use in the present embodiment.

  The upstream chamber 3 is connected to a main valve 20a via a pressure regulator 19. The first downstream chamber 4a is connected directly to the main valve 20a which is itself connected to a vacuum pump 5a. The second downstream chamber

  4b is connected to a main valve 20b which is itself

  even connected to a vacuum valve 5b. General pumps 21a, 21b are respectively connected to the upstream sides of the main valves 20a, 20b via general vacuum valves 22a, 22b, and are also connected to the vacuum pumps 5a, 5b via auxiliary valves. 23a, 23b. The general pumps 21a, 21b are used to establish the preliminary vacuum in the upstream chamber 3, the first downstream chamber 4a and the second downstream chamber 4b. 24a-24h leak / purge valves are provided for chambers 3, 4a, 4b and

pumps 5a, 5b, 21a, 21b.

  Firstly, the general vacuum valves 22a, 22b and the pressure regulator 19 are opened to establish the preliminary vacuum in the upstream chamber 3 and the first and second downstream chambers 4a, 4b by means of the general pumps 21a, 21b. Then the preparatory vacuum valves 22a, 22b are closed and the auxiliary valves 23a, 23b and the main valves 20a, 20b are opened to establish a sufficient vacuum in the upstream chamber 3 and the first and second downstream chambers 4a, 4b by means of the vacuum pumps a, 5b. In this state, the opening of the pressure regulator 19 is set to establish a higher degree of vacuum in the first downstream chamber 4a than in the upstream chamber 3, then the carrier gas and the raw material gas are supplied and the diaphragm 16 is regulated so as to establish an even greater vacuum in the second downstream chamber 4b than in the first downstream chamber 4a. This regulation can also be carried out by means of the main valve 20b. Another adjustment is made so that each of the chambers 3, 4a, 4b is kept at a constant degree of vacuum during the generation of the ultrafine particles and the formation of a film by ejection of the beam. This adjustment can be done manually or automatically by a pressure detection

  in rooms 3, 4a, 4b and a commu-

  the pressure regulator 19, the main valves

blades 20a, 20b and diaphragm 7.

  The upstream chamber 3 and the first downstream chamber 4a can be equipped with independent vacuum pumps for the vacuum control mentioned above. However, if a single vacuum pump 4a is used, as explained previously, to establish the vacuum in the flow direction of the beam to adjust the fluid levels in the upstream chamber 3 and in the first downstream chamber 4a, the difference The pressure between them can be kept constant even when the vacuum pump 5a has a certain pulsation. It is therefore easier to maintain a steady state of flow that is easily

  affected by a variation of the pressure difference.

  The suction established by the pumps 5a, 5b is advantageously applied from above, in particular in the first and second downstream chambers 4a, 4b, because this suction from the top prevents to a certain extent

  the descent of the beam under the effect of gravity.

  The following modifications can be made to the apparatus embodiment described above. First, the convergent-divergent nozzle 1 may be inclined vertically or horizontally, or may be designed to perform a scanning movement over a certain interval to form a film on a larger surface. This inclination or sweeping motion is advantageous when associated

  to the rectangular nozzle shown in Figure 4C.

  It is also possible to make the nozzle 1 of an insulating material such as quartz and to apply microwaves to it, so as to produce active ultra-thin particles, or to form the nozzle in a translucent material and irradiating the flow with light of various wavelengths, such as ultraviolet light, infra-red light or laser light. In addition, several nozzles 1 can be used to generate several beams simultaneously. In particular, the connection of several nozzles 1 to

  independent upstream chambers 3 allows simultaneous generation

  This is done by bundling of different fine particles, thus producing a stratification or mixed capture of different fine particles or even the generation of new fine particles by cross-beam collisions. The substrate 6 may be designed to be vertically or horizontally movable, or rotatably supported to receive the beam over a large area. The substrate may also be unwound and advanced from a coil to receive the beam, to subject a band-shaped substrate to treatment with the fine particles. The treatment with fine particles may furthermore be applied to

  a substrate 6 in the form of a rotating drum.

  The embodiment described above comprises the upstream chamber 3, the first downstream chamber 4a and the second downstream chamber 4b, but it is also possible to remove the second downstream chamber 4b or to connect additional downstream chambers or other chambers. at the second downstream chamber. The first downstream chamber 4a can be implemented in an open circuit and the upstream chamber 3 is pressurized, or the upstream chamber 3 can be implemented in an open circuit if the pressure is reduced in the first downstream chamber 4a. . It is also possible to pressurize the upstream chamber 3, for example in an autoclave, and to establish a depression in the first downstream chamber and

in the following downstream rooms.

  In the preceding explanation, the active ultra-fine particles are generated in the upstream chamber 3, but they can also be generated elsewhere and supplied to said chamber with the carrier gas. It is furthermore possible to provide a valve for opening and closing the throttling nozzle I and for intermittently opening and closing this nozzle in order to store

  momentarily the fine particles in the upstream chamber 3.

  The energy supply on the downstream side, including the groove 2, of the nozzle 1 can be synchronized with the opening and closing of the nozzle to significantly reduce the charge of the vacuum circuit and to obtain a flow

  pulsation of fine particles, while making efficient use of

  the gaseous raw material. For a given vacuum state, it is easier to obtain a higher vacuum

  on the downstream side by these intermittent openings and closings.

  In this case, a chamber can be provided for temporarily storing fine particles between the upstream chamber

  3 and the throttling-spreading nozzle 1.

  It is furthermore possible to use a plurality of jet nozzles I in series and to regulate the ratio between the upstream side pressure and the nozzle side pressure of each nozzle in order to maintain a constant beam speed, and to use a spherical chamber to prevent

the formation of dead spaces.

  According to the invention, fine particles can be transported in a flow or ejection stream, in uniform dispersion, or in the form of a supersonic beam. Supersonic or subsonic transport of fine particles can therefore be achieved in a spatially independent state, while regulating

  surely the speed. It is therefore possible to trans-

  safely carrying the active fine particle particles to the sensing position in the active state, and accurately adjusting the kinetic energy at the time of sensing, at ejection. It is furthermore planned to achieve a new reaction domain, realized by the presence of a beam in the form of an extremely high velocity flow, and by the conversion of thermal energy into kinetic energy at beam formation. , in order to keep the fine particles in an energetically frozen state. Furthermore, by using the energetically frozen state mentioned above, it is possible to offer the speed control method according to the invention the possibility of defining a microscopic state of the molecules present in the fluid to treat a transition of one state to another. More particularly, it opens up the possibility of a new gaseous chemical reaction in which the molecule is defined at its energy level and receives an energy corresponding to this level. It is planned a new area of energy transfer that can be

  easily used to obtain international compounds

  Molecules formed with relatively weak intermolecular forces, such as a hydrogen bond

or a van der Waals force.

  It goes without saying that many modifications can be made to the method described and shown

  without departing from the scope of the invention.

Claims (10)

  1. A method for controlling the speed of fine particles, characterized in that it consists in placing a   convergent-divergent nozzle (1) in the flow path   finely particulate matter and to give a P / Po0 ratio a pressure P of a downstream side at a pressure Po of an upstream side, the value of a critical pressure ratio, or a lower value.   2. Method according to claim 1, characterized in that the nozzle is implemented in a state of optimal relaxation.   3. Method according to claim 1, characterized in that the derivative of the profile of the inner channel of the nozzle varies continuously and is zero at the throat (2) of the nozzle.   4. Method for adjusting the speed of   cules, characterized in that it consists in placing a   convergent-divergent nozzle (1) on the flow path   fine particles, to give the ratio P / Po of a pressure P of a downstream side at a pressure Po of an upstream side, a value equal to a critical pressure ratio, or a lower value, and to choose appropriately the ratio of the area of the section of an opening to that a throat (2) of the nozzle.   5. Process according to claim 4, characterized   in that the nozzle is operated in a state optimal relaxation.   6. Process according to claim 4, characterized   in that the derivative of the profile of the internal channel of the nozzle varies continuously and is equal to zero at the throat (2) of the nozzle.   7. Method for adjusting the speed of   cules, characterized in that it consists in placing a   convergent-divergent nozzle (1) on the flow path   thin particles and to give a P / Po0 ratio of a pressure P of a downstream side at a pressure P of an o upstream side a value greater than a critical ratio pressure.   8. Process according to claim 7, characterized   in that the derivative of the profile of the inner channel of the nozzle varies continuously and is zero to one throat (2) of the nozzle.   9. A method for controlling the speed of fine particles, characterized in that it consists in placing a convergent-divergent nozzle (1) on the flow path of the fine particles, to give a P / Po ratio of a pressure P from a downstream side at a Po0 pressure on an upstream side a value greater than a critical pressure ratio, and to properly select the ratio of the area of the section   an opening to that of a groove (2) of the nozzle.   10. Process according to claim 9, characterized   in that the derivative of the profile of the internal channel of the nozzle varies continuously and is equal to zero at the throat (2) of the nozzle.