Electron beam device for surface treatment

Abstract

The present description relates to an electron beam device (100) comprising: - a treatment chamber (130) having a longitudinal direction (Z); - at least one electron beam source (110), each source being suitable for emitting an electron beam in a beam plane (PF) substantially transverse to the longitudinal direction so as to induce a plasma or an evaporation point in the treatment chamber for the treatment of a surface of a workpiece (106), said at least one electron beam source being external to the treatment chamber; - a pumping chamber (120) connected to a first vacuum pump (126), to the treatment chamber and to the at least one electron beam source, the pumping chamber being positioned between said treatment chamber and said at least one electron beam source, and being suitable for performing differential vacuum pumping of said treatment chamber; - at least one first port (122) for passing the electron beam between the treatment chamber and the pumping chamber; and - at least one second port (124) for passing the electron beam between the pumping chamber and the at least one electron beam source.

Description

DESCRIPTION TITLE: Electron beam device for surface treatment technical field

[0001] This description relates in general to an electron beam device for surface processing, for example for thin film deposition on a surface, cleaning, layer densification and / or surface etching. Previous technique

[0002] Surface treatment, for example a substrate surface or, more generally, a part surface, typically refers to a mechanical, chemical, electrochemical, and / or physical operation that modifies the surface's appearance or function to adapt it to specific operating conditions. By extension, the following description includes etching techniques within the definition of surface treatment.

[0003] Surface treatment includes surface coating techniques, for example metallic coating techniques, and in particular thin film deposition techniques on a surface.

[0004] There are various techniques for depositing a thin film onto a surface, for example a substrate surface, including physical vapor deposition (PVD) techniques.

[0005] Among these techniques, electron beam physical vapor deposition (EBPVD) is a physical vapor deposition technique in which a target under high vacuum is bombarded by an electron beam, usually emitted by a tungsten filament. The beam The electron beam causes the atoms or molecules of the target to transition into the gaseous phase. At least some of these atoms or molecules then precipitate as a solid onto the surface to be treated, coating the surface with a thin layer of these precipitated atoms or molecules. One drawback of this technique is filament degradation, which can, for example, lead to a non-uniform evaporation rate. Furthermore, a constraint is the need for a high vacuum, sometimes less than 10⁻¹⁰ m³. 4 mbar.

[0006] The sputtering technique involves directing a plasma containing relatively heavy charged particles, such as argon ions (Ar+) from at least partially ionized argon gas (Ar), towards a target to sputter particles of the target material(s). At least some of these sputtered particles are deposited onto a surface, such as a substrate, to form a thin layer of the material(s). The plasma can be generated, for example, by applying electromagnetic radiation to the gas to be ionized at low pressure. One constraint of this technique is to avoid contamination between the plasma source and the area where the particles are sputtered onto the surface; another constraint is maintaining a relatively high vacuum, for example, less than or equal to 10⁻¹² m³ / s. 2 mbar.

[0007] Furthermore, these different techniques, as well as others not described but known to the person in the profession, are implemented by dedicated devices, which are generally not versatile, that is to say, which generally do not allow switching from one technique to another. Summary of the invention

[0008] There is a need for a device adapted to surface treatment that is capable of implementing different techniques (multipurpose surface treatment device), for example to implement different thin film deposition techniques, but also to clean a surface, to densify a surface layer, and / or to perform an engraving from a surface.

[0009] In particular, it would be desirable to have an electron beam device for surface treatment, in which the electron beam can be formed without a filament.

[0010] One embodiment overcomes all or part of the disadvantages of known surface treatment devices, and in particular of known thin film deposition devices.

[0011] One embodiment provides for an electron beam device comprising: a treatment chamber having a longitudinal direction; - at least one electron beam source, each source being adapted to emit an electron beam in a beam plane substantially transverse to the longitudinal direction so as to induce a plasma or an evaporation point in the treatment chamber for the treatment of a surface of a part; at least one first orifice for passage of the electron beam in said treatment chamber, the diameter of the minimum circle in which said first orifice is inscribed being less than or equal to one-eighth, for example less than or equal to one-tenth, of the smallest dimension of a cross-section of the treatment chamber taken in the beam plane.

[0012] According to one embodiment, the treatment chamber includes a target.

[0013] According to one embodiment, the treatment chamber includes a first support base adapted to support the target.

[0014] According to a particular embodiment, the first support base is mobile.

[0015] According to one embodiment, the first support base comprises, or consists of, a crucible, for example a cooled crucible.

[0016] According to one embodiment, the treatment chamber includes a second support base adapted to support the part to be treated.

[0017] According to a particular embodiment, the second support base is mobile.

[0018] According to one embodiment, at least one electron beam source is external to the treatment chamber

[0019] According to one embodiment, the device includes a deflection device, such as an electromagnet or a permanent magnet, adapted to deflect the electron beam in the treatment chamber.

[0020] According to a particular embodiment, the deflection device is mobile.

[0021] According to one embodiment, the device comprises a pumping chamber connected to a first vacuum pump and to the treatment chamber, the pumping chamber being adapted to perform differential vacuum pumping of said treatment chamber.

[0022] According to one embodiment, the treatment chamber is delimited by walls forming a cylindrical or parallelepiped body, and the pumping chamber is positioned against a lateral wall of the body, inside or outside said body.

[0023] According to a particular embodiment, the pumping chamber is coaxial with the treatment chamber.

[0024] According to one embodiment, at least one first orifice is between the pumping chamber and the treatment chamber, and the device includes at least one second electron beam passage orifice between the pumping chamber and at least one electron beam source.

[0025] According to one embodiment, the diameter of the minimum circle in which at least one second orifice is inscribed is less than or equal to one eighth, for example less than or equal to one tenth, of the smallest dimension of the cross-section of the treatment chamber taken in the beam plane.

[0026] According to one embodiment, at least one electron beam source comprises an electron generation chamber and a tube between the electron generation chamber and the processing chamber.

[0027] According to one embodiment, the tube is connected to the electron generation chamber and the pumping chamber, and at least one second orifice is between the pumping chamber and the tube.

[0028] According to one embodiment, at least one electron beam source includes a focusing device, such as an electromagnet, adapted to focus the electron beam, and for example to direct it towards the treatment chamber.

[0029] According to one embodiment, the device includes a second vacuum pump connected to the treatment chamber and / or a third vacuum pump connected to at least one electron beam source.

[0030] According to one embodiment, the device includes several electron beam sources external to the treatment chamber.

[0031] According to a particular embodiment, at least two of the electron beam sources are adapted to emit electrons along two beam planes parallel to each other.

[0032] According to one embodiment, at least one first orifice, and in some cases, at least one second orifice, corresponds to an orifice of a diaphragm.

[0033] According to one embodiment, the device comprises: a target biasing source at a voltage between 0 and 10 kV, preferably between 2 and 5 kV; and / or - a target cooling element.

[0034] One embodiment provides for an electron beam device comprising: a treatment chamber having a longitudinal direction; - at least one electron beam source, each source being adapted to emit an electron beam in a beam plane substantially transverse to the longitudinal direction so as to induce a plasma or an evaporation point in the treatment chamber for the treatment of a surface of a part; said at least one electron beam source being external to the treatment chamber; - a pumping chamber connected to a first vacuum pump, to the treatment chamber and to at least one electron beam source, the pumping chamber being positioned between said treatment chamber and said at least one electron beam source, and being adapted to perform differential vacuum pumping of said chamber treatment; at least one first electron beam passage orifice between the treatment chamber and the pumping chamber; and at least one second electron beam passage orifice between the pumping chamber and at least one electron beam source.

[0035] According to one embodiment, - the diameter of the minimum circle in which at least one first orifice is inscribed is less than or equal to one-eighth, for example less than or equal to one-tenth, of the smallest dimension of a cross-section of the treatment chamber taken in the beam plane; and / or - the diameter of the minimum circle in which at least one second orifice is inscribed is less than or equal to one eighth, for example less than or equal to one tenth, of the smallest dimension of the cross-section of the treatment chamber taken in the beam plane.

[0036] According to one embodiment, at least one first orifice is positioned in a side wall of the treatment chamber so that an electron beam emitted by at least one electron beam source can penetrate through said at least one first orifice into said treatment chamber.

[0037] According to one embodiment, at least a second orifice is positioned in a side wall of the pumping chamber such that an electron beam emitted by at least one electron beam source can penetrate through said at least a second orifice into said pumping chamber.

[0038] According to one embodiment, at least one electron beam source, the treatment chamber and the pumping chamber form a closed assembly.

[0039] According to one embodiment, the treatment chamber includes a target adapted to, under the effect of the electron beam or plasma, emit particles towards the part in order to induce a thin film deposition process on said part by a sputtering technique or an electron beam evaporation technique.

[0040] According to one embodiment, the treatment chamber includes a first support base adapted to support the target, said first support base being, for example, movable

[0041] According to one embodiment, the first support base comprises, or consists of, a crucible, for example a cooled crucible.

[0042] According to one embodiment, the device further comprises: a target biasing source at a voltage between 0 and 10 kV, preferably between 2 and 5 kV; and / or - a target cooling element.

[0043] According to one embodiment, the treatment chamber includes a second support base adapted to support the part to be treated, said second support base being for example mobile.

[0044] According to one embodiment, the device includes a deflection device, such as an electromagnet or a permanent magnet, adapted to deflect the electron beam in the treatment chamber, said deflection device being for example mobile.

[0045] In one embodiment, the treatment chamber is delimited by the walls of a cylindrical or parallelepiped-shaped body, and the pumping chamber is positioned against a lateral wall of the body, inside or outside the exterior of said body; the pumping chamber being, for example, coaxial with the treatment chamber.

[0046] According to one embodiment, the at least one electron beam source comprises an electron generation chamber and a tube between the electron generation chamber and the processing chamber; each tube being connected to the pumping chamber; and the at least one second orifice being between the pumping chamber and the tube of the at least one electron beam source.

[0047] According to one embodiment, at least one electron beam source includes a focusing device, such as an electromagnet, adapted to focus the electron beam, and for example to direct it towards the treatment chamber.

[0048] According to one embodiment, the device includes a second vacuum pump connected to the treatment chamber and / or a third vacuum pump connected to at least one electron beam source.

[0049] According to one embodiment, the device includes several electron beam sources external to the treatment chamber.

[0050] According to one embodiment, at least two of the electron beam sources are adapted to emit electrons along the same beam plane or along two beam planes parallel to each other.

[0051] According to one embodiment, at least one first orifice, and / or at least one second orifice, corresponds to an orifice of a diaphragm.

[0052] According to one embodiment, the device is adapted to be implemented: - thin film deposition by cathodic sputtering; - thin film deposition by beam evaporation of electrons in vapor phase; - plasma cleaning; - plasma layer densification; and / or - Plasma engraving. Brief description of the drawings

[0053] These features and advantages, as well as others, will be described in detail in the following description of particular embodiments, given by way of non-limiting example, in relation to the attached figures, among which:

[0054] Figure 1 is a schematic cross-sectional view of an electron beam device according to a first embodiment;

[0055] Figure 2 is a schematic cross-sectional view of an electron beam device according to a second embodiment;

[0056] Figure 3 is a top view of an electron beam device similar to the device in Figure 2; and

[0057] Figure 4 is a top view of an electron beam device according to a third embodiment. Description of the implementation methods

[0058] The same elements have been designated by the same reference numerals in the different figures. In particular, structural and / or functional elements common to the different embodiments may have the same reference numerals and may have identical structural, dimensional and material properties.

[0059] For the sake of clarity, only the steps and elements necessary for understanding the described embodiments have been shown and are detailed. In particular, the current or voltage supply systems, the systems Regarding the gas supply, the systems for potentially polarizing the target and / or the surface to be treated are not detailed, as the described embodiments are, unless otherwise specified, compatible with standard systems. Similarly, the supply current or voltage levels, or the polarization voltage, are not detailed.

[0060] Unless otherwise specified, when referring to two connected elements, this means directly connected without any intermediate elements other than conductors, and when referring to two coupled elements, this means that these two elements can be connected or linked through one or more other elements.

[0061] In the description that follows, when referring to absolute position qualifiers, such as "front", "back", "top", "bottom", "left", "right", etc., or relative position qualifiers, such as "above", "below", "superior", "inferior", etc., or to orientation qualifiers, such as "horizontal", "vertical", etc., unless otherwise specified, reference is made to the orientation of the figures or to an electron beam device in a normal operating position.

[0062] In the following description, when referring to an electron beam plane, or beam plane, it refers to the plane of emission of one or more electron beams by one or more electron beam sources. When there are multiple electron beam sources, they can be configured to emit electron beams along a single beam plane or along several substantially parallel beam planes. When referring to a longitudinal direction, it refers to the direction perpendicular to the beam plane(s). A cross-section of a chamber of The treatment corresponds to a section of the treatment chamber along a plane perpendicular (transverse plane) to the longitudinal direction. When the transverse plane corresponds to a beam plane, it is referred to as a cross-section taken in a beam plane.

[0063] Unless otherwise specified, the expressions "approximately", "roughly", "about", and "on the order of" mean within 10%, preferably within 5%.

[0064] Figure 1 is a schematic cross-sectional view of an electron beam device 100 according to a first embodiment.

[0065] Device 100 comprises three separate chambers: - an electron generation chamber 112 having a first volume VI; - a pumping chamber 120 having a second volume V2; and - a 130 treatment chamber having a third volume V3.

[0066] The electron generation chamber 112 is part of an electron beam source 110, or electron source, which is adapted to emit at least one electron beam F in one direction of a beam plane PF.

[0067] The electron beam source 110, the treatment chamber 130 and the pumping chamber 120 form a closed, preferably sealed, assembly.

[0068] The pumping chamber 120 is connected to the treatment chamber 130 and to the electron beam source 110, and positioned between the treatment chamber 130 and the electron beam source 110. For example, a common wall separates the pumping chamber 120 and the treatment chamber 130 and another common wall separates the pumping chamber 120 and the electron beam source 110.

[0069] The electron beam source 110 is preferably filament-free. The beam source The electron 110 may include, or consist of, for example, a plasma source in which the plasma is obtained by interaction between high-frequency electromagnetic radiation and a low-pressure gas, such as the plasma source described in patent application FR3062770A1. In this way, the electron-generating plasma source, and thus forming an electron source, can be placed in a vacuum different from that of the treatment chamber, offering freedom in the choice of pressure and / or nature of the gas for both the treatment chamber and the plasma source.

[0070] In the embodiment of Figure 1, the treatment chamber 130 is located between a cylinder 10 (cylindrical body) and the pumping chamber 120.

[0071] The treatment chamber 130 is closed by a lower wall 131, corresponding to a central portion of the lower base of the cylinder 10, an upper wall 133, corresponding to the upper base of the cylinder 10, and a side wall 132, having a first portion common with an upper portion of the side wall of the cylinder 10 connecting the lower and upper bases of said cylinder, a second portion common with an upper wall 128 of the pumping chamber 120, and a third portion common with a first side wall 121 (internal side wall) of the pumping chamber 120.

[0072] In this embodiment, the pumping chamber 120 is positioned inside the cylinder 10 and has a crown shape with the same axis as the cylinder.

[0073] The pumping chamber 120 is closed by a second side wall 123 (external side wall) common with a lower portion of the side wall of the cylinder 10, the internal side wall 121, the upper wall 128, and a lower wall 129, the upper and lower walls of The pumping chamber connects the internal and external side walls of the pumping chamber. The internal side wall 121 and the upper wall 128 of the pumping chamber 120 are common with the side wall 132 of the treatment chamber 130. The lower wall 129 of the pumping chamber 120 corresponds to a peripheral portion of the lower base of the cylinder 10.

[0074] Thus, the treatment chamber 130 is defined by the space between the cylinder 10 and the pumping chamber 120. In other words, the volume V3 of the treatment chamber 130 corresponds approximately to the volume of the cylinder 10 minus the volume V2 of the pumping chamber 120.

[0075] The upper wall 128 of the pumping chamber 120 is shown oblique to the beam plane PF. Alternatively, the upper wall 128 of the pumping chamber 120 could be substantially parallel to the beam plane PF. According to another alternative, the upper wall 128 of the pumping chamber 120 could correspond to a portion of the upper base of the cylinder 10, i.e., the internal wall 121 of the pumping chamber 120 could extend to the upper base of the cylinder 10.

[0076] Cylinder 10 is represented as a right circular cylinder, as can also be seen in the top view in Figure 3 described later. The longitudinal direction Z (or axial direction) of the treatment chamber 130 corresponds in this mode to the axis of the circular cylinder 10. D3 denotes the smallest cross-sectional diameter of the portion of treatment chamber 130 enclosed by the pumping chamber (small diameter), and D4 denotes the cross-sectional diameter of the portion of treatment chamber 130 not enclosed by the pumping chamber (large diameter). D3 is smaller than D4.

[0077] Other shapes and configurations of the treatment chamber and pumping chamber are possible. For example, the body can be cylindrical (not circular), or parallelepiped-shaped, as illustrated in Figure 4 described later, or even any other suitable shape. The pumping chamber can be positioned inside or outside this cylindrical or parallelepiped-shaped body. For example, the pumping chamber can be positioned outside the body, against a side wall of the body, which then corresponds to a side wall of the treatment chamber.

[0078] The pumping chamber 120 is connected to a first vacuum pump 126. The use of a pumping chamber separate from the treatment chamber allows for differential pumping.

[0079] Furthermore, the fact that the pumping chamber 120 is positioned between the processing chamber 130 and the electron beam source 110 creates an intermediate pumping chamber 120 between the electron generation chamber 112 and the processing chamber 130. For example, the pumping chamber 120 has a pressure P2 intermediate between the pressure PI in the electron generation chamber 112 and the pressure P3 in the processing chamber 130. This allows for differentiated pressure control in the electron generation chamber 112, for electron production, and in the processing chamber 130 for processing a substrate 106, as explained later, and thus optimizes the operating pressures in the electron generation chamber 112 and in the processing chamber 130.

[0080] The treatment chamber 130 includes a process gas inlet 138, connected to a process gas supply (not shown). Examples of gases Treatment involves rare gases such as He, Ne, Ar, Kr or Xe or reactive gases such as O2, N2, F2, CH4, SF6.

[0081] A second vacuum pump 142 can be connected to the treatment chamber 130, for example, to control an ultimate vacuum in said treatment chamber, particularly in evaporation mode. The deposition of thin films by evaporation sometimes requires very low vacuums (typically less than 10⁻¹¹ Å). 5 mbar), which may require the presence of a reinforced pump dedicated to the treatment chamber.

[0082] The processing chamber 130 is adapted to support a target 104, for example, by means of a first support base 134 assembled inside the processing chamber. The first support base 134 can be movable along the longitudinal Z direction, for example, by means of a first motor 135. This can allow a first distance ZI to be varied in the longitudinal direction between the target 104 and the beam plane PF. More generally, the target can be movable in translation and / or rotation, for example, to control the position and shape of the target's wear zone. Only one target is shown, but the processing chamber could contain several targets, for example, several targets on the first support base.

[0083] The target 104 can be placed in a crucible which can constitute or form part of the first support base 134, particularly if used in an evaporation deposition technique.

[0084] The treatment chamber 130 is adapted to support a workpiece, for example a substrate 106, at least one surface of which is to be treated. A second support base 136 can be assembled inside said treatment chamber to support the substrate 106. The second support base 136 can be movable along the longitudinal Z direction, for example by means of a second motor 137. This can allow to vary a second distance Z2 in the longitudinal direction between the substrate 106 and the beam plane PF. More generally, the part to be treated can be mobile in translation and / or rotation.

[0085] The pumping chamber 120 communicates with the treatment chamber 130 via a first port 122, and with the electron beam source 110 via a second port 124. The first and second ports are preferably aligned in the direction of emission of the electron beam (direction X in Figure 1). Thus, the electron beam emitted by the electron beam source 110 in the X direction enters the treatment chamber 130 via the pumping chamber 120 through the first and second ports 122 and 124.

[0086] In the case where there are several directions of emission of electron beam in the PF beam plane, several first and second orifices are then preferably provided, each first orifice being then preferably aligned with a second orifice along one of the emission directions, so that each electron beam emitted in a given emission direction can enter the treatment chamber via the pumping chamber through first and second orifices aligned in said emission direction.

[0087] The first orifice 122 can be positioned in the inner side wall 121 of the pumping chamber 120, i.e. in the side wall 132 of the treatment chamber 130, and the second orifice 124 can be positioned in the outer side wall 123 of the pumping chamber 120. The inner and outer side walls of the pumping chamber are opposite in the X emission direction of the electron beam.

[0088] There may be several first and second orifices, particularly if there are multiple sources of electron beam, as illustrated later in relation to figure 2.

[0089] In the case where there are several first and second orifices, the first orifices can be positioned along a first circumference of the inner side wall 121 of the pumping chamber 120, corresponding to a first circumference of the side wall 132 of the treatment chamber 130, and the second orifices can be positioned along a second circumference of the outer side wall 123 of the pumping chamber 120. For example, the first and second circumferences are concentric.

[0090] More generally, for example in a variant where the pumping chamber is external to the cylindrical or parallelepiped body, each first orifice can be positioned in a wall common to the treatment chamber and the pumping chamber, and each second orifice can be positioned in another wall common to the pumping chamber and an electron beam source.

[0091] Alternatively, each first orifice can be an orifice of a first diaphragm assembled to the inner side wall of the pumping chamber, i.e., the side wall of the treatment chamber, and / or each second orifice can be an orifice of a second diaphragm assembled to the outer side wall of the pumping chamber. The inner side wall can then have a larger opening than the first orifice to accommodate the first diaphragm, and / or the outer side wall can have a larger opening than the second orifice to accommodate the second diaphragm. This variant allows, in particular, for variable orifice sizes depending on the intended application, for example, to adjust the fluidic conductance of the orifice.

[0092] The minimum diameter circle in which each first orifice 122 is inscribed is adapted to the dimensions of the treatment chamber 130, preferably to the dimensions of the treatment chamber's cross-section in the beam plane. The same conditions can be applied to the minimum diameter circle in which the second orifice 124 is inscribed.

[0093] An opening can be circular. In this case, the diameter of this circle is taken as the dimension of the opening.

[0094] Preferably, the diameter of the minimum circle in which the first orifice 122 is inscribed is less than or equal to 1 / 8, for example less than or equal to 1 / 10, for example less than or equal to 1 / 12, of the smallest dimension of the cross-section of the treatment chamber 130 taken in the beam plane PF. In the example shown, this corresponds to the small diameter D3 of the treatment chamber 130. The same conditions can be applied to the diameter of the minimum circle in which the second orifice 124 is inscribed.

[0095] Such a ratio for an orifice makes it possible to ensure a differential vacuum between the electron beam source 110, and in particular the electron generation chamber 112, and the treatment chamber 130, while minimizing contamination of the treatment chamber towards the electron generation chamber 112. Trade-offs can be found between the quantity of electrons injected into a beam of a given diameter, after focusing, and the maximum dimension of the orifice which itself controls the differential pumping.

[0096] The first vacuum pump 126 creates a vacuum in the pumping chamber 120, as well as in the treatment chamber 130 via the first orifice 122.

[0097] Thus, the first vacuum pump 126, the injection of treatment gas, and in some cases the second vacuum pump 142, allow the pressure in the treatment chamber 130 to be controlled.

[0098] The pressure in the treatment chamber 130 can be adjusted according to the treatment technique implemented in the device, for example: - between 10~ 3 mbar and 10 -1 mbar for sputtering deposition; - between 10~ 6 mbar and 10 -1 mbar for deposition by electron beam vapor phase evaporation.

[0099] In the embodiment shown in Figure 1, the electron generation chamber 112 is located at a distance from the pumping chamber 120 and the processing chamber 130. The electron beam source 110 comprises a tube 114, preferably hollow, connecting the electron generation chamber 112 and the pumping chamber 120. The second orifice 124 is then positioned between the pumping chamber 120 and the tube 114. A third passage orifice 113 is formed between the electron generation chamber 112 and the tube 114. The third orifice 113 is preferably aligned with the first and second orifices 122, 124 in the X-ray emission direction of the electron beam.

[0100] Alternatively, the electron generation chamber 112 could be attached to the pumping chamber 120 and / or the treatment chamber 130. For example, the electron generation chamber 112 could not include a tube.

[0101] The electron beam chamber 112 further includes a source gas inlet 118 connected to a source gas supply (not shown). Examples of source gases are noble gases He, Ne, Ar, Kr or Xe or reactive gases such as O2, N2, F2, CH4, SF6.

[0102] The electron beam source 110 preferably also includes an electron beam focusing device. This may be an electrostatic or magnetic focusing device, for example, an electromagnet 116 positioned around the tube 114 and connected to a coil power supply (power supply not shown). The focusing device, for example the electromagnet 116, is preferably adapted to produce a magnetic field parallel to the path of the electron beam in the tube 114, and may be adapted to guide said electron beam towards the treatment chamber 130.

[0103] Although not shown, the electron beam source 110 may include an extraction grid and / or an acceleration grid, for example between the electron generation chamber 112 and the electromagnet 116.

[0104] The first vacuum pump 126 can be adapted to create a vacuum in the electron generation chamber 112 via the pumping chamber 120 and the second orifice 124. It is possible to size the first vacuum pump 126 as well as the second orifice 124 according to the desired vacuum.

[0105] Alternatively, or as a complement, the electron beam source 110 may include a third vacuum pump 115 connected to the electron generation chamber 112, and adapted to form a higher vacuum in said chamber, and / or to compensate for any backflow from the treatment chamber 130.

[0106] In tube 114, the emitted electron beam F is directed in the X direction of the beam plane PF, perpendicular to the longitudinal direction Z.

[0107] For certain applications, the trajectory Fl of the electron beam in the treatment chamber 130 can The electron beam must follow the same direction as the emitted electron beam, or at least not be directed in any particular direction. For example, the electron beam is not directed towards target 104. The electron beam can be adapted to create a plasma using a treatment gas introduced into the treatment chamber, for example, noble gases such as He, Ne, Ar, Kr, or Xe, or reactive gases such as O2, N2, F2, CH4, or SFg. The plasma can be directed towards substrate 106 to clean and / or etch it. The plasma can also be directed towards target 104 to remove particles, and the particles directed towards substrate 106 to perform thin-film deposition using the sputtering technique.

[0108] For other applications, the electron beam trajectory F2 in the treatment chamber 130 can be deflected to follow a given direction within the treatment chamber. For example, the electron beam can be directed towards the target 104. The electron beam can, for instance, be adapted to transform molecules of the target into the gaseous phase. At least some of these molecules then precipitate as solids onto the substrate 106 to achieve thin-film deposition by the electron vapor deposition technique.

[0109] The device may include an electron beam deflection device, for example an electromagnet or a permanent magnet 140, adapted to deflect the electron beam into the treatment chamber 130. The deflection device may be at least partially positioned within the treatment chamber. Alternatively, the deflection device may be positioned entirely outside the treatment chamber.

[0110] The deflection device, for example the permanent magnet 140, can be movable along the longitudinal direction Z, for example by means of a third motor 139. More generally, the deflection device can be mobile in translation and / or rotation, and therefore be able to control or not the trajectory of electron beams over a very wide energy range of these, for example between 100 V and 50 kV.

[0111] The focusing device, for example the electromagnet 126, and the deflection device, for example the permanent magnet 140, are preferably adapted to form magnetic fields having transverse directions, for example perpendicular, to each other.

[0112] The target may be copper, tantalum or a copper or tantalum oxide, or any other solid or even liquid material capable of inducing a spraying or evaporation process, for example a metallic material or oxide.

[0113] Depending on the processing techniques implemented in the device, the target and / or the substrate can be polarized. The polarization can typically be a few tens of volts for the substrate, for example in plasma cleaning or plasma layer densification mode, and / or, for the target, any polarization voltage that allows energies to be obtained above a sputtering or evaporation threshold, typically between 100 V and 10 kV.

[0114] Figure 2 is a schematic cross-sectional view of an electron beam device 200 according to a second embodiment, which differs from the device 100 of Figure 1 in that it comprises several electron beam sources, a first source 110 and a second source 210 shown in Figure 2. A first permanent magnet 140 can be adapted to deflect an electron beam from the first source 110, and a second permanent magnet 240 can be adapted to deflect an electron beam from the second source 210. The permanent magnets can be positioned either individually on a support or on a support common 241, as illustrated, each support being, for example, movable, for example by means of a motor 239 (common in the illustrated mode). The permanent magnets can be positioned under the target 104.

[0115] Pumping chamber 120 is positioned between processing chamber 130 and each of the first 110 and second 210 electron beam sources.

[0116] A fourth vacuum pump 226 can be connected to the pumping chamber 120 near the second source 210, in addition to the first vacuum pump 126 which is preferably connected near the first source 110.

[0117] The electron beam device 200 comprises at least two first orifices 122, 222 and two second orifices 124, 224. The first orifices 122, 222 are positioned in the inner side wall 121 of the pumping chamber 120, i.e., in the side wall 132 of the treatment chamber 130 in the configuration shown. The second orifices 124, 224 are positioned in the outer side wall 123 of the pumping chamber 120.

[0118] The first and second orifices 122, 124 associated with the first electron beam source 110 are preferably aligned in the direction of emission of the electron beam by said first source. The first and second orifices 222, 224 associated with the second electron beam source 210 are preferably aligned in the direction of emission of the electron beam by said second source.

[0119] Each of the first and second electron beam sources can be similar to electron beam source 110 in Figure 1, but the volume V4 of the second electron generation chamber 212 is not necessarily equal to volume VI of the first electron generation chamber 112.

[0120] In the mode shown, the electron beam sources are positioned to emit electrons substantially along the same beam plane PF. Alternatively, electron beam sources can be positioned to emit electrons along different parallel beam planes.

[0121] The other features of device 200 in Figure 2 may be similar to those of device 100 in Figure 1. Variants are described in connection with the figure. 1 can also be applied to device 200 in the figure 2.

[0122] It is possible to have more than two electron beam sources, as well as additional vacuum pumps associated with other electron beam sources. The pumping chamber is then positioned between the treatment chamber and each of the electron beam sources. The first and second orifices associated with each electron beam source are preferably aligned in the direction of electron beam emission from that source.

[0123] For example, Figure 3 shows a top view of a device similar to the device in Figure 2, in which a third electron beam source 310 can optionally be positioned.

[0124] At least one electron beam source can be adapted to form low-energy electrons, typically between 0.1 and 2 keV, suitable for plasma cleaning, plasma layer densification, plasma etching and / or sputtering, and to form high-power electrons, typically between 2 keV and 30 keV with an intensity typically between 10 and 200 mA per source, more suitable for vapor phase electron beam evaporation.

[0125] By multiplying the electron beam sources assembled around the treatment chamber, the overall intensity of the electrons formed can be multiplied accordingly.

[0126] Figure 4 is a top view of an electron beam device 400 according to a third embodiment, which differs from devices 100 and 200 in Figures 1 to 3 primarily in that the body 40 is parallelepiped-shaped, rather than cylindrical. The treatment chamber 430 is delimited by walls of this parallelepiped-shaped body and by the pumping chamber 420, which forms a parallelepiped-shaped ring positioned within the parallelepiped-shaped body. According to an alternative (not shown), the pumping chamber can be positioned outside the parallelepiped-shaped body against one or more lateral walls of said body.

[0127] The smallest dimension of a cross-section of the treatment chamber 430 taken in the beam plane then corresponds to the width L3, which corresponds to the width of the body L4 less the width of the pumping chamber.

[0128] The electron beam sources 110, 210, 310 shown can be similar to the sources described previously and can be positioned to emit electrons along several directions X, X', Y of the same beam plane PF, or along several directions of several parallel beam planes. Furthermore, sources can be positioned on two different lateral walls of the body, for example, two parallel walls and / or two perpendicular walls. Tl

[0129] Various embodiments and variants have been described. A person skilled in the art will understand that certain features of these various embodiments and variants could be combined, and other variants will become apparent to a person skilled in the art.

[0130] Finally, the practical implementation of the described methods and variants is within the reach of a person in the trade, based on the functional indications given above.

Claims

CLAIMS Electron beam device (100; 200; 400) comprising: - a treatment chamber (130; 430) having a longitudinal direction (Z); - at least one electron beam source (110, 210, 310), each source being adapted to emit an electron beam in a beam plane (PF) substantially transverse to the longitudinal direction (Z) so as to induce a plasma or an evaporation point in the treatment chamber (130; 430) for the treatment of a surface of a part (106); said at least one electron beam source being external to the treatment chamber; - a pumping chamber (120; 420) connected to a first vacuum pump (126), to the treatment chamber and to at least one electron beam source, the pumping chamber being positioned between said treatment chamber and said at least one electron beam source, and being adapted to perform differential vacuum pumping of said treatment chamber; - at least one first orifice (122; 222) for the passage of the electron beam between the treatment chamber and the pumping chamber; and - at least one second orifice (124; 224) for the passage of the electron beam between the pumping chamber and at least one electron beam source. Device according to claim 1, wherein: - the diameter of the minimum circle in which at least one first orifice is inscribed is less than or equal to one-eighth, for example less than or equal to one-tenth, of the smallest dimension (D3, L3) of a cross-section of the treatment chamber (130) taken in the beam plane; and / or - the diameter of the minimum circle in which the at least one second orifice (124) is inscribed is less than or equal to one-eighth, for example less than or equal to one-tenth, of the smallest dimension of the cross-section of the treatment chamber (130) taken in the beam plane. Device according to claim 1 or 2, wherein the at least one first orifice (122; 222) is positioned in a side wall (132) of the treatment chamber such that an electron beam emitted by the at least one electron beam source can penetrate through said at least one first orifice into said treatment chamber.A device according to any one of claims 1 to 3, wherein at least one second orifice (124; 224) is positioned in a side wall (123) of the pumping chamber such that an electron beam emitted by at least one electron beam source can penetrate through said at least one second orifice into said pumping chamber. A device according to any one of claims 1 to 4, wherein the at least one electron beam source, the treatment chamber, and the pumping chamber form a closed assembly. A device according to any one of claims 1 to 5, wherein the treatment chamber (130; 430) comprises a target (104) adapted to emit particles toward the part (106) under the effect of the electron beam or plasma in order to induce a thin-film deposition process on said part by a sputtering technique or an electron beam evaporation technique. A device according to claim 6, wherein the treatment chamber (130; 430) comprises a first support base (134) adapted to support the target (104), said first support base being, for example, movable. A device according to claim 7, wherein the first support base comprises, or consists of, a crucible, for example, a cooled crucible. A device according to any one of claims 6 to 8, further comprising: - a target biasing source (104) at a voltage between 0 and 10 kV, preferably between 2 and 5 kV; and / or - a target cooling element. A device according to any one of claims 1 to 9, wherein the treatment chamber (130; 430) comprises a second support base (136) adapted to support the part (106) to be treated, said second support base being, for example, movable. A device according to any one of claims 1 to 10, comprising a deflection device (140, 240), such as an electromagnet or a permanent magnet, adapted to deflect the electron beam in the treatment chamber (130; 430), said deflection device being, for example, movable. A device according to any one of claims 1 to 11, wherein the treatment chamber (130; 430) is delimited by walls of a cylindrical or parallelepiped-shaped body, and the pumping chamber (120; 420) is positioned against a lateral wall of the body, either inside or outside said body; the chamber of pumping being, for example, coaxial with the treatment chamber. Device according to any one of claims 1 to 12, wherein at least one electron beam source (110, 210, 310) comprises an electron generation chamber (112, 212) and a tube (114, 214) between the electron generation chamber and the treatment chamber (130; 430); each tube being connected to the pumping chamber (120; 420); and at least one second orifice (124) being between the pumping chamber and the tube of at least one electron beam source. Device according to any one of claims 1 to 13, wherein at least one electron beam source (110, 210, 310) comprises a focusing device (116, 216), such as an electromagnet, adapted to focus the electron beam, and for example to direct it towards the treatment chamber (130; 430).A device according to any one of claims 1 to 14, comprising a second vacuum pump (142) connected to the treatment chamber (130; 430) and / or a third vacuum pump (115) connected to at least one electron beam source (110, 210, 310). A device according to any one of the claims. 1 to 15, comprising several electron beam sources (110, 210, 310) external to the treatment chamber (130; 430). . Device according to claim 16, wherein at least two of the electron beam sources are adapted to emit electrons along the same beam plane or along two beam planes parallel to each other. Device according to any one of the claims 1 to 17, wherein at least one first orifice, and / or at least one second orifice, corresponds to an orifice of a diaphragm. Device according to any one of the claims 1 to 18, in which the device is adapted to be implemented: - thin film deposition by cathodic sputtering; - thin film deposition by electron beam vapor phase evaporation; - plasma cleaning; - plasma layer densification; and / or - Plasma engraving.

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