Cooled manipulator for ultrahigh vacuum-compatible process device, ultrahigh-vacuum-compatible process device, and ultrahigh vacuum deposition method

Abstract

The invention relates to a cooled manipulator (10) for an ultrahigh-vacuum-compatible process device for a structure comprising one or more layers. According to the invention, the cooled manipulator for an ultrahigh-vacuum-compatible process device comprises: - a cooling device (12) comprising a solid material; - a rotating support (14) secured to the cooling device; - a tank (16) fed by a flow of a cryogenic fluid, configured to be moved between two positions (P1) and (P2), the first in which the tank is in contact with the cooling device, the second in which the tank is not in contact with the cooling device.

Description

Cooled manipulator for ultra-high vacuum process device, ultra-high vacuum process device, and ultra-high vacuum deposition method technical field

[0001] The present invention relates generally to a cooled manipulator.

[0002] It relates more specifically to a cooled manipulator usable in a device for implementing a treatment process (in particular deposition or engraving) under vacuum, compatible with ultra-high vacuum, of a structure comprising one or more layers.

[0003] The invention finds a particularly advantageous application in the deposition of materials under vacuum and more particularly under ultra-high vacuum.

[0004] It also relates to a device for implementing an ultra-high vacuum process and an ultra-high vacuum deposition method. Technological background

[0005] Vacuum processing methods for structures comprising one or more layers (or "vacuum processes") include, in particular, material deposition processes, dry etching processes, heat treatment processes, oxidation processes, and nitriding processes. Deposition processes include, in particular, sputtering, molecular beam epitaxy, chemical vapor deposition, and atomic layer deposition. Etching processes include, in particular, reactive ion etching and plasma etching.

[0006] Combined with lithography and wet etching techniques, vacuum processes enable the creation of micro and nanometric structures with applications in diverse fields such as microelectronics, optoelectronics and biotechnology.

[0007] The quality of the vacuum used during these vacuum processes is essential to ensure the conformity of the deposits, including in particular the purity and crystalline structure of the deposit, and the quality of the etchings, including in particular the Directionality and homogeneity of the engraving. The vacuum quality of an environment is represented by the amount of material remaining in that environment. This amount of material remaining is measured by pressure. In practice, the higher the vacuum quality of an environment, the lower the pressure, and the less material remains.

[0008] Depending on the deposition techniques used (etching, heat treatment, oxidation, nitriding) and the desired quality of the resulting deposits (etching, heat treatment, oxidation, nitriding), different vacuum levels are required. A high vacuum, meaning a vacuum at a pressure between 10⁻³ and 10⁻⁹ mbar, is sufficient for standard-quality deposition, etching, heat treatment, oxidation, and nitriding. In other words, standard-quality deposition, etching, heat treatment, oxidation, and nitriding can be carried out in a chamber, known as a vacuum chamber, where the measured pressure is between 10⁻³ and 10⁻⁹ mbar.Ultra-high vacuum, meaning a vacuum at a pressure below 10⁻⁹ mbar, is necessary for high-quality deposition, etching, heat treatment, oxidation, and nitriding, such as in molecular beam epitaxy. To achieve these high-quality depositions, etchings, heat treatments, oxidations, and nitridings, it is therefore necessary to operate in an environment where the pressure is below 10⁻⁹ mbar, i.e., an ultra-high vacuum environment.

[0009] To achieve a pressure of 10⁻⁹ mbar, the chamber must be compatible with oven heating performed prior to reaching ultra-high vacuum. Oven heating is a process of heating the chamber to desorb and remove, by pumping, molecules present on the surface of the chamber's internal walls, such as water or carbon dioxide molecules, which could contaminate the substrates placed inside the chamber during the deposition, etching, heat treatment, oxidation, or nitriding process. To be compatible with an oven heating process, the chamber materials must be able to withstand a temperature, for example, above 150°C for a period of time. several hours without being subject to outgassing phenomena that could contaminate the substrate during the deposition, etching, heat treatment, oxidation, or nitriding process. This condition specifically excludes the presence of polymer materials or other materials with high vapor pressure within the enclosure. To create an ultra-high vacuum enclosure compatible with ultra-high vacuum, all seals must be metallic, and sealing is achieved using metal membranes as well as metal-to-metal, metal-to-ceramic, or ceramic-to-ceramic contacts. The term "ultra-high vacuum compatible" is assigned to a mechanical component (for example, the enclosure and its accessories) that meets the requirements for obtaining an ultra-high vacuum environment, i.e., a pressure below 10⁻⁹ mbar, and that can be used in such an environment without causing pollution.Materials that cannot be oven-cured, and that are likely to release matter into the environment, are therefore unsuitable for such constraints.

[0010] For the implementation of certain processes, in particular the deposition of thin films of materials with a certain crystalline structure, the deposition must be carried out at cryogenic temperatures, that is to say between -273 degrees Celsius and -150 degrees Celsius.

[0011] Furthermore, to ensure the homogeneity of the processes put in place, the substrate on which the deposit is made must be able to be rotated, for example to guarantee the uniformity of the deposited material.

[0012] For the process in question to be industrially compatible, it must also be able to be carried out on substrates of a minimum size, for example, with a diameter greater than or equal to two inches. An ultra-high vacuum-compatible manipulator is subject to the same design restrictions as an ultra-high vacuum-compatible chamber.

[0013] For the deposition of certain materials in thin films, for example thin films with superconducting properties, while meeting industrial requirements, the above problems are cumulative:

[0014] - during deposition, the substrate must be cooled to cryogenic temperatures, i.e. below -150°C;

[0015] - during deposition, it is necessary to rotate the substrate to ensure homogeneous growth;

[0016] - The manipulator must be ultra-high vacuum compatible.

[0017] - The manipulator must be compatible with the specific requirements of an industrial process, in particular the processing of several substrates in succession with the shortest possible process reset time between processes. To ensure this time is as short as possible, the temperature of the substrate holder must not exceed the cryogenic temperature limit and a pressure below 10⁻⁹ mbar must be maintained.

[0018] The vacuum manipulators and process devices known to those skilled in the art cannot address all these issues simultaneously. In particular, the prior art currently exists for vacuum manipulators and process devices that only reconcile two of the following three aspects: rotation, ultra-high vacuum compatibility (i.e., being oven-safe and suitable for use in an ultra-high vacuum environment), and cooling. One of these aspects is systematically disregarded because it is presumed incompatible with the other two in a combined application. Thus, manipulators and devices that are cooled and ultra-high vacuum compatible, or cooled and rotating manipulators and devices, are primarily known, but not ultra-high vacuum compatible, cooling, and rotating manipulators, and even less so those adapted to industrial requirements.Indeed, use in an industrial environment entails additional constraints in terms of time, cost, quality, ease of maintenance, and / or productivity. In particular, to work on large substrates (greater than 2 inches in diameter), it becomes crucial to have a manipulator capable of rotation; otherwise, structures of inconsistent thickness will result. This requirement is compounded by the need for cryogenic cooling and an ultra-high vacuum environment, both essential for the quality of the processing.

[0019] In the document "An Ultra-High-Vacuum Rotating Sample Manipulator with Cryogenic Cooling," the described manipulator is not compatible with ultra-high vacuum (lower than 10⁻⁹ mbar) because PTFE is used, and it is not suitable for industrial deposition. In document US4459823, the disclosed manipulator is also not compatible with ultra-high vacuum. Furthermore, it is not suitable for industrial production, partly because the manipulator requires manual refilling with cryogenic liquid. Document US2023 / 0249306 describes a manipulator that is indeed cooled and rotating, but incompatible with a vacuum quality corresponding to a pressure below 10⁻⁹ mbar due to the presence of a rotating shaft passing through the chamber walls. The air-vacuum interface between the shaft and the chamber therefore includes a magnetic fluid seal to ensure airtightness.However, since this material cannot be oven-cured, a pressure below 10⁻⁹ mbar cannot be achieved within the chamber. Furthermore, there are also examples of cooled manipulators compatible with a vacuum quality corresponding to a pressure below 10⁻⁹ mbar, generally called "cryostat" manipulators. An example of such a cryostat is given in the document "Test cavity and cryostat for SFR thin film evaluation" by Goudket, Philippe et al., 2015.

[0020] The numerous and long-standing studies on the subject demonstrate that there is therefore a need for an ultra-high vacuum compatible manipulator that addresses all these issues at once. Summary of the invention

[0021] The invention aims to provide a solution to these problems by proposing a cooled manipulator for a device implementing an ultra-high vacuum treatment process (or "process device"), with a structure comprising one or more layers. The manipulator includes a cooling device comprising a solid material, a rotating support integral with the cooling device, and a reservoir supplied by a circulating cryogenic fluid, configured to be moved between two positions, the first in which the reservoir is in contact with the device. cooling, the second in which the tank is not in contact with the cooling device.

[0022] The manipulator is ultra-high vacuum compatible in that it contains no polymer or high vapor pressure materials. For example, it is made entirely of metal or ceramic. Advantageously, the manipulator is therefore compatible with oven curing at 150 degrees Celsius. In particular, the manipulator is compatible with this 150-degree Celsius (or higher) curing because it is made of materials capable of withstanding such temperatures for several hours. Specifically, such materials must not be subject to outgassing, especially during the curing stage, which could degrade the quality of the processing.

[0023] Advantageously, the ultra-high vacuum compatible manipulator allows processes to be carried out at cryogenic temperatures, at pressures below 10-9 mbar (10-7 Pa) and to rotate a substrate in order to ensure the homogeneity of the process applied to the substrate carried by the manipulator, while allowing the process to be carried out on several substrates in succession with a very short process reset time between processes.

[0024] The combination of these three features on the manipulator—namely, ultra-high vacuum compatibility, cooling, and substrate rotation—while respecting industrial constraints, is advantageous because it enables high-quality processing. This particularly beneficial combination of features contradicts established preconceptions in the technical field, which led manufacturers to systematically neglect one of the three characteristics.

[0025] Due to the short reset time, several successive iterations of processing techniques are possible within a given timeframe, while maintaining stable temperature conditions inside the chamber. This ensures homogeneity between the structures obtained after different iterations, in addition to resulting in significant time savings. The manipulator described is therefore This process is particularly well-suited for industrial use. The combination of the aforementioned characteristics allows for processing industrial-sized substrates (larger than 2 inches) while ensuring good spatial homogeneity across the substrate through rotation, a desired crystalline structure, and superior quality structures. Good spatial homogeneity is defined as uniformity within ±1% of the substrate surface, or even less than ±1%.

[0026] The manipulator is compatible with different types of vacuum material processing methods, for example material deposition processes or dry etching processes.

[0027] Other advantageous and non-limiting features of the manipulator according to the invention, taken individually or in all technically possible combinations, are as follows: - the manipulator is made of materials that can be oven-baked at a temperature greater than or equal to 150 degrees Celsius. - the material of the cooling device includes copper, silver or gold. - the heat capacity of the cooling device is greater than or equal to 1000 J. Kl. - the surface of the tank opposite the cooling device comprises a thermally conductive material covered with a layer of a ductile and thermally conductive material, the layer of ductile and thermally conductive material being in contact with the cooling device in the first position. - The manipulator also includes: - a substrate support tray, - a fixing device mounted on the cooling device, configured to keep the substrate support tray in contact with the cooling device. - The substrate support tray is configured to accommodate a substrate with a diameter greater than or equal to 2 inches.

[0028] The invention also proposes a process implementation device (or "process device") under ultra-high vacuum compatible comprising: - a vacuum deposition chamber, - a cooled manipulator according to one of the embodiments of the invention.

[0029] Other advantageous and non-limiting features of the vacuum process device according to the invention, taken individually or in all technically possible combinations, are as follows: - the device further comprises a double-walled enclosure positioned within the ultra-high vacuum deposition chamber, the volume separating the two walls of the double-walled enclosure being supplied with cryogenic fluid, comprising: - a first opening allowing the passage of the cooled manipulator so that the cooling device is located within the double-walled enclosure, and - a second opening allowing the transfer of the substrate support tray between the inside of the double-walled enclosure and the outside of the double-walled enclosure, - a third opening allowing the passage of a stream of atoms or molecules during deposition under ultra-high vacuum. - the device also includes effusion cells. - The device also includes instruments for monitoring the vacuum process.

[0030] The invention also proposes a method of deposition under ultra-high vacuum using a process device according to one of the embodiments of the invention, comprising the following steps: - E21) reduction of the pressure within the process device to reach a pressure less than or equal to 10-9 mbar, - E31) cooling of the cooling device by bringing the tank into contact with the cooling device and transferring a substrate-carrying tray carrying a substrate into the process device and maintaining the substrate-carrying tray in contact with the cooling device by means of the fastening device, - E41) removal of the tank, - E51) rotation of the cooling device, - E61) deposition of the material onto the substrate.

[0031] Other advantageous and non-limiting features of the vacuum deposition method according to the invention, taken individually or in all technically possible combinations, are as follows: - the deposition method further includes an oven step Eli) preceding step E21) or carried out during step E21), during which the process device is oven-cured at a temperature greater than or equal to 150 degrees Celsius.

[0032] Of course, the different features, variants and embodiments of the invention can be combined with each other in various ways as long as they are not incompatible or mutually exclusive. Brief description of the figures

[0033] The description that follows, with regard to the attached drawings, given by way of non-limiting examples, will make it clear what the invention consists of and how it can be carried out.

[0034] Regarding the attached drawings:

[0035] Figure 1 is a functional diagram of an ultra-high vacuum compatible cooled manipulator according to an embodiment of the invention;

[0036] Figure 2a and Figure 2b are functional diagrams of a cooled manipulator according to the embodiment shown in Figure 1, in two possible configurations of the invention. Figure 2a shows the cooling device in contact with the reservoir. Figure 2b shows the cooling device at a distance from the reservoir;

[0037] Figure 3 is a summary diagram of an ultra-high vacuum compatible process device according to an embodiment of the invention and comprising a cooled manipulator shown in Figure 1.

[0038] Figure 4 is a set of curves representing the evolution of the temperature at different points of an ultra-high vacuum compatible process device shown in Figure 3 during several consecutive material deposition processes.

[0039] A cooled manipulator 10 for an ultra-high vacuum compatible process device is shown in Figure 1. A manipulator is a mechanical assembly generally comprising several degrees of freedom which allows a substrate (or sample) to be held in the vacuum chamber.

[0040] The cooled manipulator 10 includes a cooling device 12 comprising a solid material, a rotating support 14 integral with the cooling device 12, and a reservoir 16 supplied by a circulation of a cryogenic fluid, for example, liquid nitrogen. The reservoir 16 is configured to be moved between two positions P1 and P2: the first P1 in which the reservoir 16 is in contact with the cooling device 12, and the second P2 in which the reservoir 16 is not in contact with the cooling device 12.

[0041] In position PI, the reservoir 16 cools the cooling device 12 by conduction. In position P2, the cooling device 12 can be rotated with the rotating support 14 as explained below.

[0042] Vacuum processes include, for example, material deposition, material etching, heat treatment, oxidation, and nitriding. Material deposition includes, for example, sputtering and molecular beam epitaxy. Material etching includes, for example, dry etching processes.

[0043] In the embodiment considered, all the elements of the cooled manipulator 10 inside the vacuum chamber in which it is used are made of materials that can be oven-cured at a temperature of 150 degrees Celsius or higher. Therefore, the manipulator 10 is not equipped with polymer seals and does not contain any high vapor pressure materials. On the contrary, the cooled manipulator 10 comprises only static seals, in particular metallic seals. Furthermore, the cooled manipulator 10 includes only low vapor pressure materials (also called, equivalently, "low vapor pressure materials"). In this way, the cooled manipulator 10 does not risk contaminating the vacuum environment by releasing material during the implementation of a processing procedure. Thus, the cooled manipulator 10 is compatible with ultra-high vacuum. In particular, the cooled manipulator 10 is compatible with an ultra-high vacuum corresponding to a pressure below 10⁻⁹ mbar, or even below 10⁻¹⁰ mbar, or even below 10⁻¹¹ mbar.

[0044] The tank 16 is, for example, made of steel and has, for example, the general shape of a hollow cylinder, having, for example, an internal volume greater than or equal to 250 cm³ and less than or equal to 1000 cm³, for example, 450 cm³, and containing the cryogenic fluid. In the embodiment considered, the tank 16 includes a supply for the circulation of the cryogenic fluid consisting of an inlet and an outlet for the circulation of the cryogenic fluid within the tank 16. In the embodiment considered, the tank 16 is configured to be continuously supplied by the circulation of the cryogenic fluid. The cooled manipulator 10 is thus usable under industrial conditions.

[0045] The tank 16 is configured to be moved from position P1 to position P2 and from position P2 to position P1 by a linear motion actuated, for example, by a pneumatic cylinder. The cylinder force reaches, for example, 1800 N. The tank 16 is, for example, mounted on bellows. When the tank 16 is brought into contact with the cooling device 12, the contact force is, for example, greater than or equal to 20 N / cm². 2 in order to obtain good thermal contact between the reservoir 16 and the cooling device 12.

[0046] Heat transfer between the reservoir 16 and the cooling device 12 is not achieved here by brush contacts. Brush contacts, through wear, create highly polluting particles, for example in the context of semiconductors. Advantageously, since the rotation of the cooling device 12 is only carried out in position P2, in which the cooling device 12 and the reservoir 16 are not in contact, there is no particles emitted by friction, ensuring ultra-high vacuum compatibility of the cooled manipulator 10.

[0047] In the embodiment considered, in order to improve the thermal contact between the reservoir 16 and the cooling device 12, the surface of the reservoir 16 opposite the cooling device 12 comprises a thermally conductive material covered with a layer of a ductile and thermally conductive material 16a, the layer of ductile and thermally conductive material 16a being in contact with the cooling device 12 in the first position. Advantageously, the ductility of the material 16a enables good mechanical contact, and consequently, good thermal contact between the reservoir 16 and the cooling device 12. The material 16a comprises, for example, a copper base coated with gold to increase its effusivity and to prevent the formation of oxides on the surface of the material 16a that would impair the mechanical and thermal performance of the material 16a.

[0048] The cooling device 12 is made of a solid material, for example, in the shape of a disc. In the embodiment considered, the solid material of the cooling device 12 comprises a material having a high specific heat capacity and good thermal conductivity, such as copper, silver, or gold. Here, good thermal conductivity is given, for example, as being greater than or equal to 200 W / m / K, or even greater than or equal to 300 W / m / K (as is the case for the aforementioned materials). In the embodiment considered, the solid material has a specific heat capacity greater than or equal to 3850 J / K.Advantageously, the use of a material with these characteristics makes it possible to extend the cooling capacity of the cooling device 12, thus ensuring a capacity for a large number of successive iterations of the treatment process before having to cool the cooling device 12 again by flipping the cooled manipulator back into the PI position, and to ensure rapid cooling of an element, for example a substrate or a substrate holder, brought into contact with the cooling device 12.

[0049] The rotating support 14 can be rotated, for example, at a speed greater than or equal to 5 revolutions per minute and less than or equal to 20 revolutions per minute. The rotational motion is transmitted, for example, by means of a rotating magnetic feedthrough. Such a rotating magnetic feedthrough is an example of a mechanism included in the cooled manipulator 10 that allows the rotating support 14 to be rotated by means of a magnetic coupling.

[0050] In the example shown, the mechanism for rotating the rotating support 14 consists of moving parts that are either inside or outside the vacuum chamber. No rotating part passes through the air-vacuum interface, and therefore no dynamic seal (such as a friction seal) is required. "Air-vacuum" is understood to mean the interface between a zone at ambient pressure and a zone at a pressure below 10⁻⁹ mbar. Thus, advantageously, to rotate the rotating support 14, the cooled manipulator 10 does not have any moving parts configured to pass through the walls of the vacuum enclosure that defines the vacuum chamber. In other words, the moving parts of the cooled manipulator 10, particularly those of the mechanism for rotating the rotating support 14, are contained within the vacuum enclosure or located outside the vacuum enclosure.The rotating support 14 is entirely within the vacuum enclosure in this example.

[0051] Indeed, here, the rotating magnetic feed consists of an association of two magnetic elements (in practice, magnets). The first of these magnetic elements is located outside the enclosure in which the rotating support 14 is placed. This first magnetic element is attached to a rotating shaft driven by a motor, the shaft and the motor also being located outside the enclosure.

[0052] A second of these magnetic elements is placed inside the vacuum chamber. The first magnetic element and the second magnetic element interact exclusively through magnetic coupling across the walls of the vacuum chamber, so that the second magnetic element follows the movements imposed by the first magnetic element (in this case, a rotational movement). The second magnetic element is mechanically coupled to the rotating support 14 and thus causes the rotating support 14 to rotate. In the illustrated example, the rotating support 14 is rotated by the second magnetic element via a gear.

[0053] To rotate the rotating support 14, the cooled manipulator 10 does not include any moving mechanical actuation parts that would pass through the chamber walls. Therefore, the rotating support 14 is rotated by a mechanism that does not include any dynamic seals such as elastomeric or ferrofluidic seals (also called magnetic seals), which would be incompatible with the requirements of an ultra-high vacuum environment with a pressure below 10⁻⁹ mbar. A dynamic seal is defined as a joint that maintains a seal between a static element and an element moving relative to the static element. The cooled manipulator 10 includes only static seals, that is, joints that maintain a seal between two elements that are stationary relative to each other. For example, the seals of the cooled manipulator 10 are metallic seals.

[0054] Alternatively, the rotating support 14 can be rotated by a mechanism comprising an arched rod hermetically sealed within a metal bellows and a ball bearing system. The arched rod, whose movement is assisted by the ball bearing system, acts as an intermediary to rotate a rotating shaft connected to the rotating support. In such a mechanism, known as a "cattail," the transmission of rotational motion is achieved through the oscillation of the flexible metal bellows, which is actuated from outside the chamber. This metal bellows hermetically seals the arched rod. The interior of the metal bellows, including the arched rod, is therefore located within the vacuum chamber.This mechanism is therefore ultra-high vacuum compatible due to the absence of passage through the chamber by moving parts and, consequently, the absence of a dynamic sealing joint, the sealing being ensured in this case exclusively by static metal seals.

[0055] In the embodiment considered, the rotating support 14 is cooled by an additional reservoir 22 containing a cryogenic fluid, for example liquid nitrogen. Advantageously, this limits the heat input to the cooling device 12 by radiation and conduction.

[0056] The cooling device 12, being fixed to the rotating support 14, can be rotated around the same axis of rotation Al as that of the rotating support 14. The axis of rotation Al corresponds to the main axis of rotation of the cooling device 12.

[0057] The tank 16 cannot be rotated. Therefore, in the PI configuration, rotation of the cooling device is impossible due to the contact between the cooling device 12 and the tank 16. To allow rotation of the cooling device 12, the cooled manipulator 10 must be switched to the P2 configuration.

[0058] Figures 2a and 2b show the cooled manipulator 10 in the two possible configurations P1 and P2. Figure 2a shows the P1 configuration, in which the reservoir 16 is in contact with the cooling device 12. In the P1 position, the reservoir 16 is configured to cool the cooling device 12 by contact. Through heat conduction, the reservoir 16, supplied with the cryogenic fluid, lowers the temperature of the cooling device 12.

[0059] In the embodiment considered, the temperature of the reservoir 16, and that of the cooling device 12 when the reservoir 16 is in contact with the cooling device 12, are lowered to cryogenic temperatures, i.e., to temperatures below -150 degrees Celsius (below 123.15 K), for example, to temperatures less than or equal to -180 degrees Celsius (below 93.15 K). Figure 2b shows configuration P2, in which the reservoir 16 is not in contact with the cooling device 12. In this configuration, the device 12 is not cooled by the reservoir 16.

[0060] Advantageously, the configuration of the cooled manipulator 10 allows for limiting the number of moving mechanical parts. The reservoir 16 is not in During rotation, it can be continuously supplied with cryogenic fluid without requiring complex parts with polymer seals that would make the cooled manipulator 10 incompatible with ultra-high vacuum. Instead, the reservoir 16 is held within the cooled manipulator 10 via metal-to-metal contacts.

[0061] In the embodiment considered, the cooled manipulator 10 further comprises: - a substrate support tray 18, - a fixing device 20 mounted on the cooling device 12, configured to keep the substrate support tray 18 in contact with the cooling device 12.

[0062] The substrate support platform 18 is configured to accommodate a substrate on which the process is carried out in a compatible ultra-high vacuum process chamber including the cooled manipulator 10.

[0063] The substrate support plate 18 is, for example, configured to accommodate a substrate with a diameter greater than or equal to 1 inch, for example, 2 inches. The substrate support plate 18 is, for example, made of a highly conductive material such as molybdenum or an alloy such as stainless steel. The substrate is, for example, made of single-crystal sapphire. In the embodiment considered, a spring ring is used on the back of the substrate to firmly press the substrate against the substrate support plate 18. The use of a single-crystal sapphire substrate and a spring ring on the back of the substrate reduces the thermal resistance between the substrate and the substrate support plate 18 and, consequently, allows for a smaller temperature difference between the substrate and the substrate support plate 18.

[0064] The fastening device 20 is configured to firmly hold the substrate support tray 18 in contact with the cooling device 12, thus reducing the thermal resistance between these two elements. In the open position, the fastening device 20 allows the substrate support tray 18 to be transferred from a loading chamber. When the fastening device 20 is in the closed position, the substrate support tray 18 is firmly pressed against the A cooling device 12 cools and maintains the substrate tray 18 and the substrate it holds. In this embodiment, a single actuator controls both the linear movement of the reservoir 16 and the opening of the clamping device 20. In configuration P1, the reservoir 16 is in contact with the cooling device 12, and the clamping device 20 is in the open position. In configuration P2, the reservoir 16 is not in contact with the cooling device 12, and the clamping device 20 is in the closed position.

[0065] The cooled manipulator 10 described above comprises only ultra-high vacuum compatible components, specifically, only metallic components with low vapor pressure. More specifically, the seals of the cooled manipulator 10 are exclusively metallic. These characteristics make the cooled manipulator 10 compatible with the requirements of an ultra-high vacuum environment, i.e., an environment with a pressure below 10⁻⁹ mbar, or even below 10⁻¹⁰ mbar, or even below 10⁻¹¹ mbar. Furthermore, the fact that the seals of the cooled manipulator 10 are exclusively metallic is advantageous for the maintenance and / or durability of the cooled manipulator 10, in addition to representing a favorable cost-effectiveness ratio from an industrial perspective.

[0066] Thus, the cooled manipulator 10 is both ultra-high vacuum compatible, configured to cool a substrate (thanks to the presence of the cooling device 12) and to rotate this same substrate relative to the enclosure inside the chamber (using the rotating support 14).

[0067] Advantageously, the cooled manipulator 10 simultaneously combines ultra-high vacuum compatibility, cooling, and substrate rotation. It is also particularly well-suited for use in an industrial environment.

[0068] Figure 3 represents a vacuum process device compatible with ultra-high vacuum 100 comprising: - a vacuum deposition chamber 40, - a cooled manipulator 10 according to one of the embodiments of the invention.

[0069] The ultra-high vacuum compatible process device 100 is configured to perform the deposition of materials onto the substrate carried by the substrate carrier platform 18. The deposition of materials can be carried out, for example, by sputtering or by molecular beam epitaxy.

[0070] In the context of the invention, the air-vacuum connection between the cooled manipulator 10 and the enclosure 40 to which the cooled manipulator 10 is attached is advantageously achieved by metal-to-metal contacts, i.e., metal seals. These metal-to-metal contacts are adapted to the requirements of an ultra-high vacuum environment.

[0071] Indeed, as detailed previously, using a rotating magnetic bushing to rotate the rotating support 14 of the cooled manipulator 10 advantageously eliminates the need for moving parts passing through the walls of the enclosure 40. This eliminates the need for dynamic seals (such as elastomeric or magnetic seals) and allows the use of metallic seals on the air-vacuum connection located at the level of the cooled manipulator 10 mounted on the enclosure 40. These metallic seals ensure airtightness within the enclosure 40 and therefore maintain vacuum quality. The use of metallic seals is advantageous from an industrial perspective because it guarantees the airtightness of the assembly with a solution that is resistant to high temperatures (above 150 degrees Celsius), inexpensive, and easy to maintain.

[0072] By vacuum-air connection, it is understood that there is a connection between a part of the implementation device 100 at a pressure equal to atmospheric pressure, e.g. 1 atm (i.e. about 1 bar) and a part of the implementation device 100 at a pressure less than 10-9 mbar (i.e. an ultra-high vacuum environment, inside the enclosure 40).

[0073] In the embodiment considered, the ultra-high vacuum process device 100 also includes: - a double-walled enclosure 42 positioned within the vacuum deposition enclosure 40, the volume separating the two walls of the double-walled enclosure 42 being supplied with cryogenic fluid, comprising: - a first opening 42a allowing the passage of the cooled manipulator 10 so that the cooling device 12 is located within the double-walled enclosure 42, and - a second opening 42b allowing the transfer of the substrate-carrying tray 18 between the inside of the double-walled enclosure 42 and the outside of the double-walled enclosure 42, - a third 42c opening allowing the passage of a flow of atoms or molecules during deposition under ultra-high vacuum.

[0074] Supplying cryogenic fluid to the volume separating the two walls of the double-walled enclosure 42 helps to limit heat input by radiation.

[0075] The first opening 42a, the second opening 42b and the third opening 42c also help to limit heat input by radiation by limiting the space required for, respectively, the passage of the cooled manipulator 10, the transfer of the substrate carrier platform 18 and the passage of the flow of atoms or molecules during deposition under ultra-high vacuum.

[0076] In the embodiment considered, the ultra-high vacuum compatible process device 100 includes effusion cells 50. The ultra-high vacuum compatible process device 100 is in this embodiment a molecular beam epitaxy frame enabling the epitaxial growth of thin films on the substrate.

[0077] In the embodiment considered, the ultra-high vacuum process device 100 includes vacuum process monitoring instruments. These measuring instruments allow, among other things, the measurement of the thickness of material deposited on the substrate, the measurement of the growth rate of the deposited material, the characterization of the crystallographic structure of the deposited material, and the determination of the composition of the deposited material.

[0078] Figure 4 shows the substrate temperature during the growth of an aluminum layer on it, using the device according to one of the described embodiments. The graph also shows the cell temperatures of aluminum effusion used. As these graphs show, a temperature below 110K on the substrate can be maintained for 20 minutes during deposition. Advantageously, this temperature below 110K is maintained even during operation of the effusion cell placed in the ultra-high vacuum 100 compatible process device, even when this cell reaches temperatures on the order of several hundred degrees Celsius and is located close to the substrate.

[0079] This ability to maintain the substrate at a lower temperature than that of the effusion cell is advantageous for industrial applications of the device. Indeed, thanks in particular to the use of a bulk material with a specific heat capacity greater than or equal to 3850 JK⁻¹, the substrate temperature remains low (below 110 K) for a sufficient period to perform several successive iterations of the vacuum treatment process.

[0080] The invention also relates to ultra-high vacuum deposition methods. The ultra-high vacuum compatible vacuum process device 100 can, for example, be advantageously used for implementing such methods.

[0081] The invention also relates to a method of deposition under ultra-high vacuum using a process device, and comprising the following steps: - a step E21) of reducing the pressure within the process device 100 to reach a pressure less than or equal to 10-9 mbar, - a step E31) of cooling the cooling device 12 by bringing the reservoir 16 into contact with the cooling device 12 and transferring a substrate-carrying tray 18 carrying a substrate within the process device 100 and maintaining the substrate-carrying tray 18 in contact with the cooling device 12 by means of the fastening device 20, - a step E41) of removing tank 16, - a step E51) of rotating the cooling device 12, - a step E61) of depositing the material onto the substrate.

[0082] Preferably, the ultra-high vacuum deposition method also includes an oven step (Eli) preceding step E21) or carried out during step E21), during in which the process device 100 is baked at a temperature greater than or equal to 150 degrees Celsius.

[0083] Of course, the different features, variants and embodiments of the invention can be combined with each other in various ways as long as they are not incompatible or mutually exclusive.

[0084] The present invention is in no way limited to the embodiment described and represented, but a person skilled in the art will be able to make any variation in accordance with the invention.

[0085] Alternatively, the material of the cooling device 12 includes aluminum, silver, or gold.

[0086] Alternatively, the ultra-high vacuum process device compatible with 100 includes: - a vacuum engraving chamber, - a cooled manipulator 10 according to one of the embodiments of the invention.

[0087] Alternatively, the ultra-high vacuum process device compatible with 100 includes: - a spray chamber, - a cooled manipulator 10 according to one of the embodiments of the invention.

Claims

Demands 1. Cooled manipulator (10) for an implementation device (100) of an ultra-high vacuum processing method, compatible with ultra-high vacuum, of a structure comprising one or more layers, the manipulator comprising: - a cooling device (12) comprising a solid material, - a rotating support (14) attached to the cooling device (12), - a tank (16) supplied by a circulation of a cryogenic fluid, configured to be moved between two positions (PI) and (P2), of which a first position in which the tank (16) is in contact with the cooling device (12) and a second in which the tank (16) is not in contact with the cooling device (12).

2. Cooled manipulator (10) according to claim 1, wherein the manipulator (10) is made of materials that can be oven-baked at a temperature greater than or equal to 150 degrees Celsius.

3. Cooled manipulator (10) according to any one of claims 1 and 2, wherein the material of the cooling device (12) comprises copper, silver, aluminum or gold.

4. Cooled manipulator (10) according to any one of claims 1 to 3, wherein the heat capacity of the cooling device (12) is greater than or equal to 1000 JK-1.

5. Cooled manipulator (10) according to any one of claims 1 to 4, wherein the surface of the reservoir (16) opposite the cooling device (12) comprises a thermally conductive material covered with a layer of a ductile and thermally conductive material (16a), the layer of ductile and thermally conductive material (16a) being in contact with the cooling device (12) in the first position.

6. Cooled manipulator (10) according to any one of claims 1 to 5, further comprising: - a substrate support tray (18), - a fixing device (20) mounted on the cooling device (12) and configured to keep the substrate support tray (18) in contact with the cooling device (12).

7. Cooled manipulator (10) according to claim 6, wherein the substrate-holding tray (18) is configured to accommodate a substrate with a diameter greater than or equal to 2 inches.

8. Device for implementing (100) an ultra-high vacuum treatment process, compatible with ultra-high vacuum, of a structure comprising one or more layers and comprising: - a vacuum deposition chamber (40), - a cooled manipulator (10) according to any one of claims 1 to 7.

9. Implementation device (100) according to claim 8, further comprising: - a double-walled enclosure (42) positioned within the vacuum deposition enclosure (40), the volume separating the two walls of the double-walled enclosure (42) being supplied with cryogenic fluid, comprising: - a first opening (42a) allowing the passage of the cooled manipulator (10) so that the cooling device (12) is located within the double-walled enclosure (42), and - a second opening (42b) allowing the transfer of the substrate-carrying tray (18) between the inside of the double-walled enclosure (42) and the outside of the double-walled enclosure (42), - a third opening (42c) allowing the passage of a flow of atoms or molecules during deposition under ultra-high vacuum.

10. Implementation device (100) according to claim 8 or 9, further comprising effusion cells (50).

11. Implementation device (100) according to any one of claims 8 to 10, further comprising vacuum process monitoring measurement instruments.

12. Method of deposition under ultra-high vacuum using an implementing device (100) according to any one of claims 8 to 11, comprising the following steps: - E21) reduction of pressure within the process implementation device to reach a pressure less than or equal to 10-9 mbar, - E31) cooling of the cooling device by bringing the tank into contact with the cooling device and transferring a substrate-carrying tray carrying a substrate into the process implementation device and maintaining the substrate-carrying tray in contact with the cooling device by means of the fastening device, - E41) removal of the tank, - E51) rotation of the cooling device, - E61) deposition of the material onto the substrate.

13. Ultra-high vacuum deposition method according to claim 12, further comprising an oven step Eli) preceding step E21) or carried out during step E21), during which the process implementation device is oven-cured at a temperature greater than or equal to 150 degrees Celsius.

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