Reactor with removable reaction unit

Abstract

The invention relates to a reaction chamber (100) comprising a removable reaction unit (300) and a sensitive housing (200). The invention also relates to a reactor (1000) incorporating said reaction chamber, and to an assembly (2000) comprising said reactor. Furthermore, the invention relates to a method suitable for reducing the preventive maintenance time of the reactor described above, and to the use of the reactor in the homoepitaxial or heteroepitaxial deposition of a silicon carbide or gallium nitride film on a semiconductor substrate.

Description

Technical Field

[0001] The present invention relates to the field of epitaxial deposition of semiconductor films on substrates, and in particular to a reaction chamber with a removable reaction unit and a reactor incorporating the reaction chamber. The present invention also relates to an assembly and a method suitable for reducing the preventive maintenance time of a reactor.

[0002] Additionally, although not exclusively, the present invention relates to the field of deposition of silicon carbide and gallium nitride films on semiconductor substrates in hot wall, lateral flow, homoepitaxial or heteroepitaxial reactors. Background Art

[0003] Semiconductor films made by epitaxial growth, also called epilayers, are formed by deposition in a reaction chamber of a reactor. The deposited material can be the same as the substrate, or include a different semiconductor with specific desired qualities. Epitaxy techniques allow control of the crystal structure formed on the substrate and improvement of the characteristics of the epilayer surface, making them suitable for the manufacture of highly complex microprocessors and memory devices.

[0004] Typically, the reaction chamber is heated to the desired temperature prior to film deposition and then kept substantially constant throughout the deposition process. To this end, an insulation system is used to reduce the energy required to reach and maintain the nominal temperature for the deposition process.

[0005] Epitaxial growth equipment for the SiC industry typically includes a reactor containing a reaction and deposition chamber where the chemical vapor deposition process occurs. As a result of the deposition process, various parts of the chamber will experience unwanted product buildup and will need to be cleaned or replaced after reaching a certain thickness to avoid affecting the quality and performance of the reaction and deposition process.

[0006] These consumables are typically made of graphite with or without a protective coating and may require varying amounts of cleaning before being discarded. It should be noted that the amount of undesirable buildup varies between different consumable parts as well as within the same part, as some parts may experience more stubborn / intense latching of deposited material due to location and shape.

[0007] As a result, consumable components within the reaction chamber, as well as the walls and parts that make up the reaction chamber itself, require preventative maintenance operations that require periodic entry into the reaction chamber to remove, maintain, or replace the components and parts.

[0008] These operations severely impact the downtime of the reactor and its output, which can also be observed from the advantageous reactor designs used in the art, such as those described in EP1570107 and WO2021105841.

[0009] In these cases, removing, cleaning and replacing the relevant parts of the reaction chamber is a time-consuming process, mostly done manually. In fact, the replacement or cleaning of parts requires an operator to access the various components located inside the reaction chamber from within the machine.

[0010] In general, the process requires complete cooling of the reactor and the reaction chamber, does not wish to expose the latter to air, and requires the presence of an operator during all stages.

[0011] In the best case, where the reactor is of the removable type, it is possible to avoid the operator having to enter the reactor machine to carry out the time-consuming and uncomfortable removal of individual components from the reaction chamber. This is achieved by providing means for pulling the reactor as a whole out of the machine. However, this process still suffers from the above-mentioned disadvantages: entry into the chamber is not fully automated or automatable, the reactor is exposed to the air, and its displacement (and handling) is cumbersome. Most importantly, the downtime is still disadvantageously long, since it takes at least eight hours to complete all the necessary operations and requires the presence of an operator.

[0012] It is therefore desirable to reduce the downtime of an epitaxial deposition reactor during preventive maintenance operations of the reaction chamber and its consumable parts. Furthermore, it is desirable to automate the removal of those parts of the reaction chamber where deposition occurs, as well as the insertion and replacement processes. Furthermore, during such processes, it is desirable to avoid exposure of the chamber to air, to facilitate its handling, and to avoid the presence of an operator. Summary of the invention

[0013] This application claims priority to IT application 102023000024660 filed on November 21, 2023, the entire contents of which are incorporated herein by reference. In particular, but not exclusively, the following are incorporated by reference: claims 1-22, Figure 1-4 and the corresponding parts of the description.

[0014] This application also claims priority to IT application 102023000024663 filed on November 21, 2023, the entire contents of which are incorporated herein by reference. In particular, but not exclusively, the following are incorporated by reference: claims 1-16, Figure 1-3 and the corresponding parts of the description.

[0015] An object of the present invention is to overcome the disadvantages of the prior art. More specifically, an object of the present invention is to provide a reaction chamber equipped with a removable reaction unit, in particular, but not exclusively, for use in a hot wall reactor for depositing SiC and GaN films on semiconductor substrates of the same or different materials.

[0016] Another object of the invention is to provide a reactor equipped with a reaction chamber having the above characteristics, as well as an assembly and a method suitable for preventive maintenance operations on the reactor with reduced downtime. The reaction chamber, reactor, assembly and method allow avoiding exposure of the reaction chamber to the air while providing the optional opportunity to handle the removable reaction unit with a fully automated system.

[0017] The primary objectives set out above are achieved by the invention as described in the accompanying claims, which form an integral part of the present description.

[0018] Please note that the use of reference signs in the claims does not limit their scope. The only purpose of reference signs is to make the claims easier to understand.

[0019] This summary is provided to introduce some concepts in a simplified form. These concepts are further described in the detailed description of the example embodiments disclosed below. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A simplified schematic diagram of a reaction chamber according to an embodiment of the present invention is provided.

[0021] Figure 2 I and II in FIG. 1 respectively show simplified schematic diagrams of a base and a removable reaction unit of a reactor according to an embodiment of the present invention.

[0022] Figure 3 A schematic diagram of a reaction chamber according to another embodiment of the present invention is provided.

[0023] Figure 4 A simplified schematic diagram of components according to one aspect of the present invention is provided.

[0024] Figure 5 I and II in Figures provide simplified schematic diagrams of reaction chambers according to embodiments of the present invention.

[0025] Figure 6 A simplified schematic diagram of a sensitive housing of a reaction chamber according to an embodiment of the present invention is provided.

[0026] Figure 7 A simplified schematic diagram of a sensitive housing of a reaction chamber according to an embodiment of the present invention is provided.

[0027] Figure 8 A simplified schematic diagram of a reaction chamber according to an embodiment of the present invention is provided.

[0028] It should be understood that the elements in the drawings are shown for simplicity and clarity and have been omitted and / or not drawn to scale. For example, the size of some elements in the drawings may be reduced or enlarged relative to other elements to help improve the understanding of the illustrated embodiments of the present disclosure. DETAILED DESCRIPTION

[0029] Although certain embodiments and examples are disclosed below, those skilled in the art will appreciate that the invention extends beyond the specifically disclosed embodiments and / or uses of the invention and their obvious modifications and equivalents. Therefore, it is intended that the scope of the disclosed invention should not be limited by the specifically disclosed embodiments described below.

[0030] Cylindrical epitaxial reactors, such as those described in EP1570107 and US2022411961, have proven commercially successful due to the uniformity and efficiency of chamber heating, simplicity of construction, and quality of deposited films. They can operate at temperatures between 1000-1800°C for SiC and GaN epitaxial film deposition.

[0031] These cylindrical reactors usually extend fairly uniformly in the longitudinal horizontal direction and present a substantially circular cross section.

[0032] They comprise a reaction chamber formed by one or more structural elements. Two of these structural elements may exhibit high sensitivity, for example they may be made of graphite and exhibit a half-moon shape. They may be heated via induction means, for example one or more induction coils wound around the reactor. The other structural elements of the reaction chamber may be made of the same or different material, for example SiC, to give preferential current flow in the sensitive elements and to accelerate their inductive heating. In this text and hereinafter, the term "sensitive element" refers to an element made of a material having high sensitivity, i.e. an element that can be effectively heated by induction.

[0033] The reaction chamber described in EP1570107 and US2022411961 is formed via the assembly of the above-mentioned components. This assembly creates an internal space of substantially parallelepiped shape in which the actual reaction takes place. This simple parallelepiped shape cannot be separated and moved as a whole from the constituting sensitive element; in general, the chamber presents a complex profile of substantially circular cross-section and cross-lines, because it is the result of the combination of all the above-mentioned elements.

[0034] The above reaction chamber is usually surrounded by an upper shell and a lower shell made of a thermally insulating material. For this purpose, porous carbonaceous materials can be used, such as carbon composites made of chopped carbon fibers, optionally interconnected or pressed together in a matrix.

[0035] The above-mentioned cylindrical reactor can be surrounded by a housing, which can be made of quartz or other materials that are relatively transparent to induction heating and resistant to high temperatures. The housing can have a double wall and can be cooled with a cooling fluid, such as water flowing in the gap between its two walls. This enables the housing to maintain its structural properties even when exposed to high temperatures.

[0036] A cylindrical reactor as described in the above non-limiting example (provided for illustrative purposes only) requires long downtime for preventive maintenance operations, which are necessary due to the accumulation of deposited materials on the inner surface of the reaction chamber (including the surfaces of disposable or removable components - such as components for rotating, supporting, and aligning the substrate, and / or components for improving the fluid dynamics inside the reaction chamber (guiding the carrier gas, precursor gas, and waste gas flow)).

[0037] In one aspect, the present invention relates to a reaction chamber for epitaxially depositing a semiconductor film on a substrate, comprising:

[0038] (a) A substantially hollow sensitive housing that extends along a longitudinal direction (x) and has an inner surface and an outer surface; and

[0039] (b) A removable reaction unit that has an inner surface and an outer surface and includes at least four walls that are connected or connectable to each other and extend along the longitudinal direction. The reaction unit also has two open or partially open sides: an upstream side and a downstream side. These sides are parallel to a transverse plane (yz) perpendicular to the longitudinal direction.

[0040] The expression "connected to each other" means that one or more of the at least four walls are either integral with each other (e.g., they can be made as a single piece) or connected together by permanent or releasable means (e.g., they can be permanently connected by welding or releasably connected by a mechanical interlocking system, rivets, or screws).

[0041] The removable reaction unit can have a box-like shape with four walls substantially parallel to the longitudinal direction. However, they can also converge slightly towards the upstream or downstream side. The cross-section of each wall in the transverse plane can present a straight profile or be curved or bent.

[0042] For example, the reaction chamber can be elliptical.

[0043] One of the four walls of the reaction unit is a bottom wall that is provided with a receiving area adapted to receive a substrate holder. The side (upstream or downstream) of the reaction unit can be completely open or have upstream and / or downstream walls.

[0044] In any case, the upstream side includes upstream holes adapted to receive the flow of carrier and precursor gases for epitaxial deposition. Similarly, the downstream side includes downstream holes adapted to discharge the exhaust gas flow. The holes may occupy the entire upstream / downstream side, or may be holes that pass through the respective upstream and / or downstream walls.

[0045] The reaction unit according to the present invention is mechanically connected to the sensitive housing via a releasable coupling device, which can be used to support and / or fasten and / or align the reaction unit with / to the sensitive housing. The reaction unit and the releasable coupling device are suitable for removing the reaction unit from the sensitive housing or inserting it into the sensitive housing as a whole.

[0046] This allows the reaction unit to be removed and replaced in a simple manner without having to reach inside the reactor machine, or without having to move the entire reactor and sensitive elements outside the machine to access its internal surfaces and any internal parts and components (if any), thereby exposing them to the air.

[0047] The sensitive housing is suitable for being heated by induction, for which purpose it may advantageously be made of graphite. The reaction unit is heated by the sensitive housing primarily by radiation from the sensitive housing.

[0048] The sensitive housing may be in the form of a hollow prism or cylinder with a polygonal, circular, oval or elliptical cross section in a transverse plane. A substantially circular cross section may allow an advantageously uniform heat distribution.

[0049] The sensitive housing can advantageously be opened on one or both sides of the transverse plane (yz) to facilitate access to the reaction unit. During operation, the opening can advantageously be closed with an insulating cover.

[0050] To further adjust the thermal radiation distribution, the sensitive housing may present a variable thickness in the longitudinal direction (x) and / or in the transverse plane (yz), e.g. Figure 5 , Figure 6 and Figure 7 discussed in.

[0051] In another embodiment of the present invention, the four walls of the reaction unit include a top wall and two side walls. The top wall or bottom wall can be advantageously connected to the two side walls and the upstream and downstream sides by a releasable coupling device. This embodiment allows easy access to the internal components of the chamber (disposable graphite components and / or the inner surface of the wall) for maintenance and / or replacement.

[0052] In another embodiment of the present invention, the releasable coupling means is a non-permanent mechanical interlock or fastening mechanism, such as a hook and loop mechanism, snap or any other female-male fastening / connecting means suitable for quick and easy release.

[0053] In another embodiment of the present invention, the inner surface of the sensitive housing is provided with grooves or protrusions which are suitable for supporting, positioning and / or releasably fastening the reaction unit thereto.

[0054] The reaction unit may also advantageously be provided with projections or recesses on its outer surface, which are adapted to releasably engage with recesses or projections on the inner surface of the sensitive housing by a non-permanent mechanical interlocking or fastening mechanism. Such a mechanism particularly includes any joint with a releasable, i.e. non-permanent, interlocking shape, such as any mechanism in which a projection is adapted to latch onto a corresponding notch or hoop, and includes hook-and-loop mechanisms, buckles, etc.

[0055] In another embodiment, the top and bottom walls of the reaction unit of the invention are made of graphite, while the side walls and / or the upstream and downstream sides (if they are only partially open) are made of graphite or silicon carbide.

[0056] Advantageously, each wall of the reaction chamber may be made of graphite, but the interior surfaces of the reaction unit may be covered or coated in whole or in part with SiC, TaC or other materials to protect the graphite components during deposition or during cleaning operations.

[0057] According to a further embodiment, the reaction unit further comprises a removable cover of thermally insulating material, which is located above the downstream hole and is provided with at least one opening which is fully or partially aligned with the downstream hole and is adapted to discharge the exhaust gas flow. The opening of the cover and the downstream hole may optionally be further adapted to allow insertion and removal of the substrate holder. The removable cover may also be coupled to at least one of the four walls via a releasable fastening device.

[0058] According to another embodiment, the reaction unit may further comprise an upstream insulation element, optionally removable, located on the top and / or bottom wall at a distance ≤ 20% L from the upstream side; wherein L is the minimum distance between the downstream side and the upstream side in the longitudinal direction.

[0059] The insulating material used in the above embodiments may be a carbonaceous material, preferably a porous material. For example, a carbon composite material made of chopped carbon fibers, optionally interconnected or pressed together in a matrix, may be advantageously selected. The surfaces of these materials may be coated to increase their compactness and reduce the risk of debris generated by separation of fibers or other fragments.

[0060] According to another embodiment, the reaction unit further comprises a first transition piece, optionally removable, located above the upstream hole and adapted to be coupled to the precursor gas liner.

[0061] In another embodiment, the reaction unit of the reaction chamber according to the present invention may further include an engagement device, such as a notch, a protrusion, a hook, a ring or a sliding piece, which is suitable for mechanically coupling with the end effector of an automated handling machine so as to be integrally removed from / inserted into the sensitive housing in an automated manner. This allows the removal of the reactor unit to be upgraded from manual to automated means.

[0062] The reaction unit according to the invention is compact and suitable for handling. For example, its dimensions in the transverse plane are 200-400 mm by 30-50 mm and in the longitudinal direction are 200-500 mm. The reaction unit may typically weigh 2-10 kg, preferably 2.5-6 kg. The sensitive housing has dimensions in the longitudinal direction of 200-500 mm and a diameter and / or a main length in the transverse direction of 210-450 mm.

[0063] The reaction cell can be equipped with a plurality of inner covers adapted to be fixed around the receiving area to control the exposure of the substrate holder to the precursor gas flow and / or to protect the exposed bottom surface of the reaction cell from parasitic accumulation. During preventive maintenance, these inner covers can be easily collected from the reaction cell for cleaning or replacement. These inner covers are made of graphite and coated with SiC and / or TaC.

[0064] According to a second aspect, the present invention relates to a reactor suitable for epitaxial deposition of semiconductor films on a substrate, comprising: (i) at least one reaction chamber according to any of the preceding embodiments; (ii) an insulation system, comprising one or more insulation components, enclosing the reaction chamber; (iii) a liner suitable for guiding process gases in the reaction unit and connected to the reaction unit by a releasable connection device.

[0065] The reactor may advantageously comprise 1 to 8 reaction chambers, preferably 2 to 6 reaction chambers.

[0066] The liner may comprise a (second) transition piece which may be coupled to a first transition piece attached to the upstream side of the reaction unit.

[0067] The one or more insulating components should be made of a rigid material suitable for withstanding the high temperatures reached by the reactor. For example, although not exclusively, they may be made of a rigid carbonaceous material (e.g. a material comprising chopped carbon fibers, optionally interconnected or pressed together in a matrix).

[0068] All surfaces of the insulation components may advantageously be coated to improve their compactness and reduce the formation of debris which may result from fibers or other particles detaching from the bulk insulation material. The coating used may be a graphite-based coating.

[0069] The reactor may also advantageously comprise an outer shell, such as a double-walled quartz tube, suitable for allowing a cooling fluid to flow in the space between its two walls. It will be apparent to a person skilled in the art that other elements commonly used in a reactor as described above may be present.

[0070] One or more induction coils and / or capacitors may be located outside the reactor to heat the sensitive housing and directly or indirectly heat the reaction cells of each reaction chamber.

[0071] In a third aspect, the present invention relates to an assembly for displacing and transporting a reaction unit for preventive reactor maintenance operations. The assembly comprises the reactor described above; a transfer chamber and a unit transport chamber.

[0072] The transfer chamber has a first port provided with a first gate valve adapted to receive or unload a reaction unit from / to the reactor via one or more automated machines or via manual means, and a second port provided with a second gate valve.

[0073] The unit handling chamber is placed in communication with the transfer chamber through the second hole and the second gate valve, and is adapted to receive or unload the reaction unit from / to the transfer chamber via a motorized mechanical device.

[0074] The unit handling chamber is suitable for accommodating the reaction unit and is provided with a resealable access, such as a door, hatch, porthole or valve, suitable for removal and insertion of the reaction unit by an operator or an automated handling device.

[0075] The term "conditioning" refers to various operations or cycles suitable for preparing the reaction unit before inserting the reactor. In addition or alternatively, the operation or cycle is suitable for making the reaction unit suitable for being approached by an operator or machine, and is suitable for taking out from the assembly to remove or clean its parts. Possible cycles may include the step of generating a vacuum less than 10 mbar, and refilling under an inert gas such as argon, nitrogen, helium or xenon. In addition or in lieu of inert gas refilling, the reaction unit may undergo an inert gas purge, preferably an inert gas is argon. Before inserting the reactor, an alternative cycle suitable for performing on a new / cleaned reaction unit may include the step of heating and vacuum degassing (in this case, the vacuum should preferably be less than 1 mbar, even more preferably less than 10 -3 millibar).

[0076] In an assembly according to the invention, the transfer chamber may advantageously be adapted to also receive or unload a substrate holder from / to the reactor via the first aperture via a motorized mechanical device. The assembly according to this embodiment may optionally and advantageously include a load lock chamber placed in communication with the transfer chamber via a third aperture and a third gate valve.

[0077] Thus, the load lock chamber may receive or unload a substrate holder from / to the transfer chamber via the motorized robot through the third aperture.

[0078] The load lock chamber may additionally include a resealable access port adapted for removal and insertion of a substrate holder by an operator or an automated handling device.

[0079] According to another embodiment, the assembly according to the invention further comprises a first automated handling machine provided with a first end effector. The first end effector is adapted to engage the reaction unit to remove it from the sensitive housing and insert it into the transfer chamber, and vice versa. The first end effector may advantageously be adapted to be coupled to the reactor unit by means of engagement means present on the reactor unit, if any.

[0080] The first automated handler may also optionally be provided with a second end effector adapted to engage with the substrate holder to insert it into or remove it from the reaction unit.

[0081] These embodiments allow for automated handling of reaction cells and substrates.

[0082] In a fourth aspect, the present invention relates to a preventive maintenance method for a reaction unit of a reactor disclosed previously and comprising the steps of:

[0083] (a) releasing the liner from the reaction unit;

[0084] (b) separating the reaction unit from the sensitive housing;

[0085] (c) The reaction unit is removed from the sensitive housing as a whole by manual or automated means and then removed from the reactor.

[0086] Advantageously, step (c) may be performed according to the following sub-steps:

[0087] (c1) removing the reaction unit from the sensitive housing and then from the reactor via a first automated handling machine;

[0088] (c2) placing the reaction unit in the transfer chamber through the first hole via the first or second automated transporter;

[0089] (c3) The reaction unit is transferred to a unit transport chamber, which is placed in communication with the transfer chamber through the second hole and the valve for regulation and access.

[0090] Thus, with the reaction chamber design of the present invention, it is possible to manufacture reactors and assemblies adapted to allow easy access to the reaction unit for preventive maintenance operations, allowing its removal from or insertion into sensitive housings and reactors by manual or automatic means, and conditioning operations prior to cleaning, without exposing the chamber to the air, and ensuring safe working conditions for operators who subsequently handle the unit. This process can reduce preventive maintenance time by 70%.

[0091] Furthermore, the possible automation of the process and the specific use of connecting chambers (transfer chamber and unit handling chamber) make it possible to avoid the simultaneous presence of an operator during the displacement of a reactor and / or a reaction unit within an assembly.

[0092] According to a fifth aspect, the invention relates to the use of the reactor described above for hot-wall, lateral-flow, epitaxial deposition of silicon carbide or gallium nitride.

[0093] The illustrations presented herein are not meant to be actual views of any particular material, structure or equipment, but are merely idealized representations for describing embodiments of the present disclosure. Specifically, they are not intended to limit the scope of these aspects and embodiments in any way. In fact, for the sake of brevity, the traditional manufacture, connection, preparation and other functional aspects of the system may not be described in detail. In addition, the connecting lines shown in each figure are intended to represent exemplary functional relationships and / or physical connections between various elements. Many alternative or additional functional relationships or physical connections may exist in actual systems, and / or may not exist in some embodiments.

[0094] Figure 1 A cross section in a transverse plane (yz) of an embodiment of a reaction chamber 100 of the invention is schematically depicted. The reaction chamber is suitable for epitaxial deposition of semiconductor films on a substrate and comprises a hollow sensitive housing 200 and a reaction cell 300.

[0095] The sensitive housing extends along a longitudinal direction (x) perpendicular to the transverse plane. The sensitive housing has an inner surface 250 and an outer surface and contains a removable reaction unit 300.

[0096] The reaction unit 300 has a box-like shape. It includes four walls 310, 320, 330, 340 extending in the longitudinal direction. The four walls include a top wall 320, two side walls 330, 340 and a bottom wall 310. The bottom wall 310 is provided with a receiving area 311 suitable for receiving a substrate holder 315.

[0097] The reaction unit also includes an upstream side (not shown) and a downstream side 360 ​​parallel to the transverse plane (yz). In this embodiment, the downstream side is a wall provided with a downstream hole 361, which is suitable for receiving a flow of carrier gas and precursor gas for epitaxial deposition. The upstream side is completely open and corresponds to the upstream hole shown by the dashed line 351. The upstream hole is suitable for discharging the exhaust gas flow. The reaction unit is mechanically connected to the sensitive housing via releasable coupling devices 331, 332. It can be moved integrally relative to the sensitive housing, thereby facilitating its insertion and removal from / to the sensitive housing and reducing the time required for preventive maintenance operations.

[0098] To further facilitate preventive maintenance operations, the top wall 320 is connected to the two side walls and the upstream and downstream sides by releasable coupling means 321, such as a female-male interlocking mechanism.

[0099] By providing the reaction unit with an engagement device, such as notches 371, 372, the handling of the reaction unit can be facilitated and automated, the engagement device being suitable for coupling with the end effector of an automated handling machine. The end effector can have a fork shape, which is provided with two prongs suitable for coupling with notches 371, 372.

[0100] Figure 2 I and II in FIG. Figure 1 Schematic isometric view of the sensitive housing and reaction unit of the reaction chamber 100

[0101] Figure 2 I in FIG. 1 shows a sensitive housing 200 having a hollow cylindrical shape and extending along a longitudinal direction (x) perpendicular to the transverse plane (yz). The sensitive housing has an inner surface 250 and an outer surface and is suitable for accommodating Figure 2 The removable reaction unit 300 of II.

[0102] The sensitive housing is provided with protrusions 251, 252 extending from its inner surface and adapted to support and position the reaction unit on said surface. The reaction unit can slide in and out of the sensitive housing on these protrusions. In order to further guide and more accurately position the reaction unit with the inner surface, grooves 253, 254 can be used. These can be shaped to engage with corresponding protrusions on the outer surface of the reaction unit, e.g. Figure 2 The protrusions 331, 332 depicted in II in the figure are arranged to create an interlocking system.

[0103] Figure 2 II shows Figure 1 The reaction unit 300 , wherein the open upstream side 350 and the corresponding holes 351 are more clearly visible.

[0104] Figure 3 According to the second embodiment, Figure 2Schematic isometric view of the reaction unit depicted in II in FIG. In this case, the reaction unit is also provided with a removable cover 400 of insulating material located above the downstream side 360 ​​and provided with an opening 401. The opening is aligned with the downstream orifice 361 and is suitable for discharging the exhaust gas flow.

[0105] The reaction unit further includes a first transition piece 500 located above the upstream aperture 351 and adapted to couple with the precursor gas liner.

[0106] Figure 4 A simplified schematic diagram of an assembly 2000 according to an embodiment of the present invention is shown. The assembly is designed to facilitate the displacement and handling of the reaction unit, for example but not limited to Figure 1-3 The reactor unit shown is used for preventive reactor maintenance operations. The assembly includes a reactor 1000 coupled to a system of connecting chambers 2100, 2200, 2300.

[0107] The reactor comprises a double-walled quartz tube and is wrapped with an induction coil (not shown) for heating. The reactor also comprises an insulation system 1100 wrapped around the reaction chamber. The reaction chamber comprises a sensitive housing 200 and a reaction unit 300.

[0108] The reaction unit has a first transition piece 500 positioned above the upstream hole 351 and coupled to the liner 1200. The reaction unit also comprises a removable cover 400 of thermally insulating material, located above the downstream side 360 ​​and provided with an opening 401 aligned with the downstream hole 361. The reaction unit is equipped with engagement means 371, 372 suitable for coupling with an end effector of an automated handling machine (not shown).

[0109] The reactor can be connected to a system of connecting chambers 2100, 2200, 2300 via a downstream roller 700. The chamber system comprises a transfer chamber 2100 having a first hole 2110 provided with a first gate valve 2111 and adapted to receive or unload reaction units from / to the reactor via one or more automated machines (or, less preferably, via manual means) via a downstream roller. The transfer chamber also has a second hole 2120 provided with a second gate valve 2121.

[0110] The system of connecting chambers 2100, 2200, 2300 also includes a unit handling chamber 2200 placed in communication with the transfer chamber through a second hole 2120 and a second gate valve 2121. The unit handling chamber is suitable for receiving or unloading reaction units from / to the transfer chamber via a motorized mechanical device, and is provided with a resealable inlet 2210 suitable for taking out and inserting the reaction unit 300 by an operator or an automated handling device.

[0111] The unit handling chamber may be used to condition the reaction unit before it is removed from an assembly or inserted into a reactor via a transfer chamber.

[0112] The system of connected chambers 2100, 2200, 2300 also includes a load lock chamber 2300 placed in communication with the transfer chamber through a third aperture 2130 and a third gate valve 2131. The load lock chamber is adapted to receive or unload substrate holders from / to the transfer chamber through the third aperture via a motorized mechanism (not shown).

[0113] Advantageously, the assembly according to this embodiment may be equipped with a first automated handler (not shown) provided with a first end effector suitable for engaging the reaction unit to remove it from the sensitive housing and insert it into the transfer chamber, and vice versa.

[0114] The first automated handler may also be provided with a second end effector 3200 adapted to engage with the substrate holder to insert or remove it from the reaction unit, thereby providing a fully automated system.

[0115] Figure 5 Schematically depicts cross sections in a longitudinal plane (xz) and a transverse plane (yz) of an embodiment of a reaction chamber 100 of the present invention. The two cross sections are respectively Figure 5 I and II are shown in FIG.

[0116] The reaction chamber includes a hollow sensitive housing 200 and a reaction unit 300. The reaction unit 300 has a box-like shape and includes a top wall 320, two side walls, and a bottom wall 310.

[0117] The sensitive housing extends along a longitudinal direction (x) perpendicular to the transverse plane and has an inner surface 250 provided with protrusions 251,252 adapted to support and position the reaction unit 300. The reaction unit is provided with releasable coupling means 331,332 configured to engage with the protrusions 251,252.

[0118] Reference Figure 5 In the embodiment of the invention, the sensitive housing has a non-uniform thickness in the longitudinal direction. In this case, the upper part of the sensitive housing has a reduced thickness corresponding to the central part (B) along the longitudinal direction x relative to the peripheral part (A). This configuration will result in a higher temperature in the central part (B) where the receiving area (not shown) is located. Note that the receiving area and the substrate holder can be substantially parallel to the horizontal plane (xy).

[0119] It should be understood that there may be cases where the technical effect to be achieved should be the opposite, in which case the thickness of the central portion (B) can be increased relative to the thickness of the peripheral portion (A). Tailoring the thickness of the sensitive housing along the longitudinal direction allows controlling the temperature gradient in the longitudinal (upstream-downstream) direction, i.e. the flow direction of the process gas. This temperature gradient may affect the quality of the deposited film on the substrate, for example in terms of thickness and doping uniformity.

[0120] In general, according to any embodiment of the invention, it is advantageous to control the temperature gradient in the longitudinal direction of the reaction chamber by varying the thickness of the sensitive housing in the longitudinal direction, in particular in the portion corresponding to the receiving area. The variable thickness portion may be limited to the upper and / or lower arc of the sensitive housing.

[0121] Reference Figure 5 II, the sensitive housing has a non-uniform thickness in the transverse plane. Specifically, the cross section of the sensitive housing is thicker at an angle between 0-θ, which is formed by the direction y passing through the center of the reaction unit and is preferably symmetrical with respect to the xz plane.

[0122] In this case, the thickness variation is configured to control the temperature gradient in the y-direction, i.e. in the direction perpendicular to the longitudinal direction and in the horizontal plane. In fact, a small gradient in this direction may allow reducing the possible sublimation of the SiC film deposited on the substrate holder. This undesirable effect may occur if the periphery of the substrate in the y-direction is very hot, which may lead to marking and quality problems.

[0123] Without departing from the scope of the present invention, Figure 5 The embodiments discussed in I and II may be implemented simultaneously or separately.

[0124] Figure 6 A cross section of a hollow sensitive housing 200 in a transverse plane (yz) is schematically depicted according to an embodiment of a reaction chamber of the present invention.

[0125] The sensitive housing presents a substantially cylindrical shape and extends along a longitudinal direction (x) perpendicular to the transverse plane.

[0126] The sensitive housing has an inner surface 250 provided with protrusions 251, 252 suitable for supporting and positioning the reaction unit.

[0127] Despite the protrusions 251, 252, the sensitive housing has a first average thickness t in the transverse plane. 1 and the second average thickness t 2 >t 1 . Usually, relative to t 2 , so that t 1 It is advantageous to exhibit a thickness increase of 20-80%, preferably 30-60%.

[0128] The sensitive shell has an average thickness t 2 The portion is located symmetrically in a transverse plane (yz) relative to the vertical direction z and forms an angle between α and θ with the horizontal direction y; wherein α=-45°-0°; and θ=5°-45°.

[0129] Figure 7 A cross section of a hollow sensitive housing 200 in a transverse plane (yz) is schematically depicted according to an embodiment of a reaction chamber of the present invention.

[0130] The sensitive housing presents a substantially cylindrical shape and extends along a longitudinal direction (x) perpendicular to the transverse plane (yz). In order to reduce heating of the central part (not shown) corresponding to the reaction unit, the housing has an opening in the upper part of the base.

[0131] It will be appreciated that, as an alternative, the housing may have a plurality of openings, which may be symmetrical with respect to a horizontal plane (xy), parallel to the substrate to be processed. The opening may advantageously be located in a substantially central portion of the sensitive housing in the longitudinal direction.

[0132] Figure 8 An embodiment of a reaction chamber 100 according to the invention is shown, presenting a cross section in a transverse plane (yz) perpendicular to the longitudinal direction.

[0133] The reaction chamber comprises a hollow sensitive housing 200 and a reaction unit 300. The sensitive housing extends in the longitudinal direction and has an inner surface 250 provided with protrusions 251, 252 suitable for supporting and positioning the reaction unit 300. The reaction unit is provided with releasable coupling means 331, 332 configured to engage with the protrusions 251, 252.

[0134] The cross-section of both the sensitive housing and the reaction is elliptical. The similar flat shape of the two elements improves the heat transfer between the sensitive housing and the reaction by radiation.

[0135] The reaction unit 300 has a top wall 320, two curved side walls 330, 340 and a bottom wall 310. The bottom wall is provided with a receiving area 311 adapted to accommodate and rotationally support a substrate holder 315.

[0136] The subject matter of the present disclosure includes all novel and nonobvious combinations and subcombinations of the various processes, systems and configurations, and other features, functions, acts, and / or properties disclosed herein, as well as any and all equivalents thereof.

[0137] In the description and claims of the present application, the word "comprise" and variations thereof, such as "comprising", do not exclude the presence of other additional elements, components or stages.

[0138] The discussion of documents, contracts, materials, devices, articles etc. is included in the text solely for the purpose of providing a background to the present invention; however, it should not be construed that such material or parts thereof constitute common general knowledge in the field relevant to the present invention before the priority date of each claim attached to this application.

Claims

1. A reaction chamber (100) for epitaxially depositing a semiconductor film on a substrate, comprising: - a substantially hollow sensitive housing (200) extending along a longitudinal direction (x) and having an inner surface (250) and an outer surface; as well as - a removable reaction unit (300) having an inner surface and an outer surface and comprising: (i) four walls (310, 320, 330, 340) extending along a longitudinal direction, and (ii) an upstream side and a downstream side (350, 360) parallel to a transverse plane (yz) perpendicular to said longitudinal direction; The four walls of the reaction unit include a bottom wall (310) which is provided with a receiving area (311) suitable for receiving a substrate holder; the upstream side includes an upstream hole (351) suitable for receiving a carrier gas and a precursor gas flow for epitaxial deposition; the downstream side includes a downstream hole (361) suitable for discharging an exhaust gas flow; the reaction unit is mechanically connected to the sensitive housing via a releasable coupling device (331, 332) and is movable in an integral manner relative to the sensitive housing.

2. The reaction chamber according to claim 1, wherein: The four walls of the reaction unit include: a top wall (320) and at least two side walls (330, 340); the top wall or the bottom wall is mechanically connected to the two side walls and the upstream side and the downstream side via a releasable coupling device (321).

3. The reaction chamber according to claim 1 or 2, wherein: The releasable coupling means is a non-permanent mechanical interlock or fastening mechanism.

4. The reaction chamber according to any one of claims 1 to 3, wherein: The inner surface of the sensitive housing is provided with grooves or protrusions (251, 252, 253, 254) suitable for supporting, positioning and / or releasably fastening the reaction unit to the inner surface.

5. The reaction chamber according to claim 4, wherein: The reaction unit is provided with protrusions or grooves (331, 332) on its outer surface, which are adapted to releasably engage with the grooves or protrusions on the inner surface of the sensitive housing through a non-permanent mechanical interlocking or fastening mechanism.

6. A reaction chamber according to any one of the preceding claims, wherein: The reaction unit further comprises a removable cover (400) of insulating material, located above the downstream side and provided with at least one opening (401); the opening is fully or partially aligned with the downstream orifice and is suitable for discharging the exhaust gas flow.

7. A reaction chamber according to any one of the preceding claims, wherein: The reaction unit further comprises a first transition piece (500) located above the upstream hole and adapted to be coupled to the precursor gas liner, wherein the first transition piece is optionally detachable.

8. A reaction chamber according to any one of the preceding claims, wherein: The reaction unit further comprises an upstream insulation element (600), which is optionally detachable and is located on the top wall and / or the bottom wall at a distance ≤ 20% L from the upstream side; Wherein L is the minimum distance between the downstream side and the upstream side in the longitudinal direction.

9. A reaction chamber according to any one of the preceding claims, wherein: The top wall and the bottom wall of the reaction unit are made of graphite, and the side wall is made of graphite or silicon carbide.

10. The reaction chamber according to claim 9, wherein: The side walls are made of graphite, and the inner surface of the reaction unit is fully or partially covered or coated with SiC or TaC.

11. A reaction chamber according to any one of the preceding claims, wherein: The sensitive housing is made of graphite.

12. A reaction chamber according to any one of the preceding claims, wherein: The sensitive housing has a substantially hollow prism or cylindrical shape with a polygonal, circular, oval or elliptical cross section in a transverse plane (yz).

13. A reaction chamber according to any one of the preceding claims, wherein: The sensitive housing is open on at least one side in the transverse plane (yz).

14. A reaction chamber according to any one of the preceding claims, wherein: The sensitive housing is characterized by a variable thickness in the longitudinal direction and / or in the transverse plane (yz).

15. A reaction chamber according to any one of the preceding claims, wherein: The reaction unit further comprises a coupling device (371, 372) which is suitable for coupling with an end effector of an automatic handling machine so as to be integrally removed from / inserted into the sensitive housing.

16. A reactor (1000) suitable for epitaxially depositing a semiconductor film on a substrate, comprising: - at least one reaction chamber (100) according to any one of claims 1 to 15; - a thermal insulation system (1100) comprising one or more insulating components surrounding at least one reaction chamber; - a liner (1200) adapted to conduct process gases in a reaction unit of at least one reaction chamber and connected to the reaction unit by releasable coupling means.

17. An assembly (2000) for displacing and transporting a reaction unit for preventive reactor maintenance operations, comprising: - A reactor (1000) according to claim 16; a transfer chamber (2100) comprising a first aperture (2110) provided with a first gate valve (2111) adapted to receive or unload a reaction unit from / to a reactor via one or more automated machines or via manual means; and a second aperture (2120) provided with a second gate valve (2121); and - a unit handling chamber (2200) placed in communication with the transfer chamber through a second hole (2120) and a second gate valve (2121), and adapted to receive or unload reaction units from / to the transfer chamber via a motorized mechanical device; The unit handling chamber is suitable for adjusting the reaction unit and is provided with a resealable entrance (2210) suitable for an operator or an automated handling device to remove and insert the reaction unit.

18. The assembly of claim 17, wherein: The transfer chamber is also suitable for receiving or unloading a substrate holder from / to the reactor through the first hole via a motorized mechanical device; the assembly also includes a load lock chamber (2300), which is placed in communication with the transfer chamber through a third hole (2130) and a third gate valve (2131); the load lock chamber is suitable for receiving or unloading a substrate holder from / to the transfer chamber through the third hole via a motorized mechanical device.

19. The assembly according to claim 17 or 18 further comprises a first automated handling machine (3000) provided with a first end effector (3100), the first end effector (3100) being suitable for engaging the reaction unit to remove it from the sensitive housing and insert it into the transfer chamber, and vice versa.

20. The assembly of claim 19, wherein: The first automated transporter is provided with a second end effector (3200) adapted to engage with a substrate holder to insert it into or remove it from the reaction unit.

21. A preventive maintenance method for a reaction unit of a reactor according to claim 15, comprising the following steps: (a) releasing the liner (1200) from the reaction unit (300); (b) separating the reaction unit (300) from the sensitive housing (200); (c) The reaction unit is removed from the sensitive housing as a whole by manual or automated means and then removed from the reactor.

22. The method according to claim 21, wherein: Step (c) comprises the following additional steps: (c1) removing the reaction unit from the sensitive housing and then from the reactor via a first automated transporter (3000); (c2) placing the reaction unit in the transfer chamber (2100) through the first hole (2110) via the first or second automated transporter; (c3) The reaction unit is transferred to the unit transport chamber (2200), which is placed in communication with the transfer chamber through the second hole (2120) and the valve (2121) for regulation and access.

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