FR2839459A1 - Reactor for the deposition of a metal or ceramic coating under a rarefied atmosphere which can be applied in a sealed manner over a predefined zone on the surface of a substrate - Google Patents

Abstract

A reactor (1) for the deposition of a metal or ceramic coating on a substrate in a rarefied atmosphere is made up of a chamber (2) with its inner volume (10) connected by an outlet (3) to a air pumping unit. This volume is open in the sense that the wall incorporates an opening (4) of which the edge (5): (a) is able to be totally applied on a predefined zone (7) of the surface (8) of the substrate; (b) is equipped with a joint able to assure sealing between the external atmosphere (9) and the inner volume of the reactor whilst it is put in depression by the pumping unit. An Independent claim is also included for a machine for the deposition of a metal or ceramic coating from a source or target on a substrate under a rarefied atmosphere.

Description

<Desc / Clms Page number 1>

 The present invention relates to a new device for depositing a coating on a substrate, this coating possibly being metallic or ceramic.

 More particularly, the invention sees its application in the processes for depositing a coating in a rarefied atmosphere known under the names PVD (physical vapor deposition) CVD (chemical vapor deposition) or thermochemical treatment under partial vacuum.

 In particular, the physical vapor deposition or PVD which brings together a significant amount of these processes takes place in three stages: creation of a metallic vapor from a source (or target), transport of said vapor within a reactor and then condensation thereof on the surface of a substrate to be coated. This designation brings together three main categories according to the process for obtaining steam: by thermal effect (we speak of evaporation), by mechanical effect (we speak of spraying), by combination of the thermal effect and the mechanical effect (case of the cathode arc under vacuum).

 PVD processes are increasingly used for many applications.

 For all the applications and whatever the process, the substrate or substrates to be treated are placed in a reactor which can be in the batch (that is to say with introduction supplied by batch with breaking of the vacuum) or in the process (it that is to say with the use of successive airlocks to maintain an acceptable vacuum in the treatment chamber.

 Considering that the treatment of large parts requires the passage of the entire part in the machine, this leads to a very high cost of treatments (batch) and / or the need to build a very expensive specific machine which cannot be used profitably only for very large series.

 This is even more true when the treatment should only be applied locally on a large room. In this case, although the treated surface may be very small, it is the entire part which must be placed in the oven, taking care to protect the areas not to be covered.

 The objective of the invention is to remedy these drawbacks in order to reduce the dimensions and the cost of the machine to be used.

 The inventive idea consists in considering that the zone to be treated constitutes one of the walls of the reactor, which makes it possible to use a small machine, less expensive than those of the prior art, for the localized treatment of large surfaces. .

<Desc / Clms Page number 2>

 More particularly, the invention consists of a reactor for depositing a metallic or ceramic coating on a substrate under a rarefied atmosphere, a reactor consisting of a chamber, or enclosure, the internal volume of which communicates via an outlet to a pumping group of air not shown, characterized in that this volume is open in the sense that the wall or one of the walls of the chamber has an opening, flat or not, the border of which: - is capable of being applied entirely on an area predefined surface of the substrate, - and is equipped with a seal capable of ensuring the seal between the external atmosphere and the internal volume of the reactor when the latter is placed under vacuum by the pumping unit.

 The invention also relates to a machine for implementing a method of depositing a metallic or ceramic coating originating from a source or target on a substrate under a rarefied atmosphere, for example but not limited to a method of physical deposition in the vapor phase comprising a pumping group for the suction of the air contained in the chamber of a reactor of the machine in which the deposition takes place, characterized in that the reactor where the deposition takes place is a reactor as specified above, and in that the source (or target) as well as the vaporization means are provided inside the volume of said reactor.

 The invention will be better understood with the aid of the description below made with reference to the following appended figures: FIG. 1: view in vertical section of a reactor according to the invention according to a first variant of implementation for flat surfaces to be treated, - Figure 2: vertical sectional view of a reactor according to the invention according to a second implementation variant for non-flat surfaces to be treated, - Figure 3: in vertical section of a reactor of the Figure 1 used on a thin substrate, - Figure 4: vertical sectional view of a reactor according to the invention, according to a third variant of #uvre implementation for thin sheets.

 Reference is first made to FIGS. 1 and 2 showing a first and a second variant of implementation.

 A reactor (1) according to the invention consists of a chamber, or enclosure (2), the interior volume (10) of which communicates via an outlet (3) to an air pumping group, not shown.

<Desc / Clms Page number 3>

 The chamber constitutes an open volume which can be cylindrical as in the figure but could have other shapes (spherical shape or parallelepiped shape).

 This volume is open in the sense that the wall or one of the walls of the chamber has an opening (4), which can be plane (case of FIG. 1) or non-plane (case of FIG. 2).

 In all cases, the entire border (5) of the opening (4): - is capable of being applied entirely on a predefined area (7) of the surface (8) of the substrate, - and is equipped with a seal (6) suitable for ensuring the seal between the external atmosphere (9) and the internal volume (10) of the reactor when the latter is placed under vacuum by the pumping unit.

 The opening (4) of the substrate is provided in its shape and dimensions to completely cover the predefined area (7), which may be identical or smaller than the area to be treated, in the case where several deposits are provided successive of the same color or different colors to cover the entire area to be treated, which itself only represents part of the surface of the substrate.

 The reactor (1) behaves like a suction cup with respect to the surface to be treated and / or the predefined surface.

 The variant of FIG. 1 with planar opening applies to all flat substrates or with a large radius of curvature with regard to the area to be treated.

 The variant of FIG. 2 with non-planar opening consists in giving the joint surface the non-planar shape of the predefined zone and may be necessary for specific applications.

 The variants of FIGS. 1 and 2 can be used for solid substrates whose mechanical properties of the material and of the zone placed under vacuum support the evacuation of the interior volume (10).

 Otherwise, for example for plate-shaped substrates (11) (see FIG. 3), placing the volume (10) under vacuum can lead to rupture or irreversible deformation of the substrate.

 To overcome this drawback, a third implementation variant shown in FIG. 4 is provided.

 According to this variant of FIG. 4, the reactor further comprises a counter suction cup (12) evacuated before the interior volume (10) is evacuated, and produced so as to oppose the deflection of the shaped substrate of plate

<Desc / Clms Page number 4>

A primary vacuum (approximately 10 Pa) is then sufficient to ensure the resistance of the plate during the placing under secondary vacuum (approximately 0.01 Pa) of the reactor, generally necessary for most usable processes, prior to the treatment phase. strictly speaking.

 The counter suction cup (12) of FIG. 4 is for example a plate applying by depression on the second face (13) of the plate (11), the enclosure (2) applying on the first face (14) of said plate and covering the predefined area (7).

 The counter sucker has an outlet (15) to a pumping unit not shown in communication with a plurality of suction openings (16) each opening against the second face of the plate (11).

 For all the variant embodiments and for all the vaporization processes, the sources (or targets) as well as the vaporization means are provided inside the volume (10). It is also possible to provide means for moving the source or sources in translation or in rotation in order to increase the surface to be treated.

 More particularly, in the case of PVD processes, these may be stationary or mobile sources, knowing that the mobile sources, in particular in translation, allow a significant saving in treatment time and a uniformity in increased thickness. The case of CVD layers and thermochemical treatment does not require any additional accessories. In all cases, the arrival of the gases and the situation of the pumping unit are adapted accordingly.

 The targeted applications are not exhaustive: decoration, mechanics, optics, electronics, nuclear, aeronautics ... Depending on the applications, various masking techniques intended to precisely limit the surface treated can also be implementation (lithography, transfer, metal mask, ceramic or polymer, ink).

 Any substrate capable of sealing the system, localized evacuation and heating can be treated by these methods. Materials such as metals, ceramics, polymers, minerals, glass, wood (steamed) are thus likely to be treated using this new device.

Claims (5)

1. Reactor for depositing a metallic or ceramic coating on a substrate in a rarefied atmosphere, reactor consisting of a chamber, or enclosure (2), the internal volume (10) of which communicates via an outlet (3) to a group air pump not shown characterized in that this volume is open in the sense that the wall or one of the walls of the chamber has an opening (4), planar or not, the edge (5): - is able to be applied entirely on a predefined area (7) of the surface (8) of the substrate, - and is equipped with a seal (6) capable of ensuring the seal between the external atmosphere (9) and the internal volume (10) of the reactor when the latter is placed under vacuum by the pumping unit. 2. Reactor according to claim 1 characterized in that it further comprises a suction cup (12) evacuated prior to the evacuation of the interior volume (10), and produced so as to oppose the arrow of the plate-shaped substrate (11). 3. Reactor according to one of claims 1 to 2, characterized in that the sources or targets as well as the vaporization means are arranged in the interior volume (10). 4. Reactor according to claim 3, characterized in that it comprises means for moving the source or sources. 5. Machine for implementing a process for depositing a metallic or ceramic coating coming from a source or target on a substrate under a rarefied atmosphere, for example but not limited to a process for physical deposition in the vapor phase comprises a pumping group for the suction of the air contained in the chamber of a reactor of the machine in which the deposition takes place, characterized in that the reactor where the deposition takes place is a reactor according to one of the claims 1 to 2, and in that the source (or target) as well as the vaporization means are provided inside the volume (10).