Removable reaction part

Abstract

To provide a reaction chamber having a removable reaction part that is used for a hot wall reactor in order to accumulate a SiC or GaN film on a semiconductor substrate of the same or different material.SOLUTION: A reaction chamber 100 that is suitable for epitaxial deposition of a semiconductor film on a substrate, comprises: a hollow sensibility casing 200 that is extended along a long direction; and a removable reaction part 300 that includes an inner surface and an outer surface to the inner surface 250 of the sensibility casing, and contains an upstream side and a downstream side 360 that is parallel to four walls 310 to 340 extended along the long direction and a cross-sectional surface vertical to the long direction. The reaction part is mechanically connected to the sensibility casing via integrated means 331 and 332 that can be cancelled, and can be integrally moved to the sensibility casing.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to the field of epitaxial deposition of semiconductor films on substrates, and more particularly to a reaction chamber featuring a removable reaction section and a reactor incorporating the above reaction chamber. The present invention further relates to components and methods adapted to reduce the preventive maintenance time of the reactor.

[0002] Furthermore, the present invention relates to the field of depositing silicon carbide films and gallium nitride films on semiconductor substrates, although not exclusively, in hot-wall cross-flow homoepitaxial or heteroepitaxial reactors.

Background Art

[0003] Semiconductor films produced by epitaxial growth, also known as epi-layers, are formed by deposition within the reaction chamber of a reactor. The deposited material may be the same as the substrate or may include different semiconductors with specific desired qualities. Epitaxial technology controls the crystal structure formed on the substrate, improves the characteristics of the epi-layer surface, and makes it suitable for the manufacture of very complex microprocessors and memory devices.

[0004] Typically, the reaction chamber is heated to a desired temperature before film deposition and then the temperature is maintained substantially constant throughout the deposition process. For this purpose, an insulation system is used to reduce the energy required to achieve and maintain the nominal temperature of the deposition process.

[0005] Epitaxial growth apparatuses for SiC industry include a reactor that houses a reaction / deposition chamber where a chemical vapor deposition process occurs. As a result of the deposition process, some parts of the chamber will be subject to the accumulation of unwanted products and will require cleaning or replacement after reaching a certain thickness in order to avoid affecting the quality and performance of the reaction and deposition processes.

[0006] These device consumable parts are usually made of graphite, either coated or uncoated with a protective layer, and the number of times they can be cleaned before disposal can vary. It should be noted that the amount of unwanted accumulation varies between different consumable parts and within the same part due to location and shape, as in some parts, the deposited material may adhere more stubbornly / strongly.

[0007] As a result, the consumable parts within the reaction chamber, as well as the walls and components that make up the reaction chamber itself, require preventive maintenance operations that necessarily involve regular access to the chamber for removal, maintenance, or replacement of the above-mentioned parts and components.

[0008] These operations can significantly affect the reactor downtime and its throughput, as can be observed in advantageous reactor designs used in the art, such as those described in European Patent Application Publication No. 1570107 and International Publication No. 2021105841 pamphlets.

[0009] In these cases, the removal, cleaning, and replacement of the corresponding parts of the reaction chamber are time-consuming processes that are mainly carried out manually. In fact, the replacement or cleaning of parts requires the operator to access the individual parts located within the reaction chamber from within the machine.

[0010] Overall, the process requires complete cooling of the reactor and the reaction chamber, unwanted exposure of the latter to air, and the presence of an operator at all stages.

[0011] In the best-case scenario where the reactor is of the removable type, it is possible to avoid the operator entering the reactor machinery due to the time-consuming and cumbersome extraction of the individual components from the reaction chamber. This is done by providing means to completely withdraw the reactor from the machinery. However, the process still presents the above-mentioned drawbacks. That is, the entry into the chamber is not fully automated or is not automatable, the reactor is exposed to air, and its movement (and handling) is cumbersome. In particular, the downtime is still long, as it takes at least 8 hours for all the necessary operations to be completed and requires the presence of an operator.

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

[0013] This application claims priority to Italian Patent Application No. 102023000024660, filed on November 21, 2023, the entire content of which is incorporated herein by reference. In particular, but not by way of limitation, the incorporation by reference is made with respect to claims 1-22, Figures 1-4, and the corresponding sections of the specification of Italian Patent Application No. 102023000024660.

[0014] This application also claims priority to Italian Patent Application No. 102023000024663, filed on November 21, 2023, the entire content of which is incorporated herein by reference. In particular, but not by way of limitation, the incorporation by reference is made with respect to claims 1-16, Figures 1-3, and the corresponding sections of the specification of Italian Patent Application No. 102023000024663. SUMMARY OF THE INVENTION

Problems to be Solved by the Invention

[0015] The object of the present invention is to overcome the drawbacks of the prior art. More specifically, the object of the present invention is, inter alia, but not limited thereto, to provide a reaction chamber with a removable reaction section for use in a hot wall reactor for the deposition of SiC and GaN films on semiconductor substrates of the same or different materials.

[0016] A further object of the present invention is to provide a reactor equipped with a reaction chamber having the above characteristics, and assemblies and methods suitable for performing preventive maintenance operations on a reactor with reduced downtime. The above reaction chamber, reactor, assemblies, and methods make it possible to avoid exposure of the reaction chamber to air and provide an optional opportunity to handle the removable reaction section using a fully automated system.

[0017] The above-described main object is achieved by the present invention as described in the appended claims, which form an essential part of this specification.

[0018] It should be noted that the use of reference signs in the claims does not limit their scope. The sole purpose of the reference signs is to make it easier to understand the claims.

[0019] This summary is provided to introduce selected concepts in a simplified form. These concepts are further described in the detailed description of exemplary embodiments of the following disclosure. This summary is not intended to identify key features or essential features of the subject matter described in the claims, nor is it intended to be used to limit the scope of the subject matter described in the claims.

Brief Description of the Drawings

[0020]

Figure 1

Figure 2

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Figure 5

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Figure 8

DETAILED DESCRIPTION OF THE INVENTION

[0021] Of course, the elements in the figures are illustrated for simplicity and clarity and are omitted and / or not necessarily drawn to scale. For example, the dimensions of some of the elements in the figures may be reduced or exaggerated relative to other elements to aid in the understanding of the disclosed embodiments of the present disclosure.

[0022] Certain embodiments and examples are disclosed below, but it will be understood by those skilled in the art that the present invention extends beyond the specifically disclosed embodiments and / or uses of the present invention, as well as their obvious modifications and equivalents. Accordingly, it is intended that the scope of the disclosed invention should not be limited by the specific disclosed embodiments described hereinafter.

[0023] Cylindrical epitaxial reactors such as those described in European Patent Application Publication No. 1570107 and US Patent Application Publication No. 2022411961 have proven commercially successful due to the uniformity and efficiency of heating of the reaction chamber, the simplification of the structure, and the quality of the deposited film. For SiC and GaN epitaxial film deposition, they can operate at temperatures of 1000~°C to 1800°C.

[0024] These cylindrical reactors typically extend somewhat uniformly along the long axis in the horizontal direction and exhibit a substantially circular cross-section.

[0025] They comprise a reaction chamber formed by one or more structural elements. Two of these structural elements can exhibit high sensitivity and can be made of, for example, graphite and can exhibit a semi-circular shape. These may be heated by induction means such as one or more induction coils wound around the reactor. Other structural elements of the reaction chamber can be made of the same or different materials such as SiC to provide a preferential current flow to the sensitive elements and facilitate their induction heating. When using the term sensitive element, here and hereinafter, it means an element made of a material having high sensitivity, i.e., an element that can be efficiently heated by induction.

[0026] The reaction chamber described in European Patent Application Publication No. 1570107 and US Patent Application Publication No. 2022411961 is formed by the assembly of the above components. The assembly creates an internal space that is basically parallelepiped-shaped where the actual reaction occurs. This simple parallelepiped shape cannot be moved integrally separately from the constituent sensitive elements, and since the chamber is the result of the combination of all the above elements as a whole, it exhibits a substantially circular cross-section and a complex contour of intersection lines.

[0027] The above reaction chamber is typically enclosed by an upper casing and a lower casing made of a heat insulating material. For this purpose, a porous carbonaceous material, for example, a carbon composite made of randomly interconnected or pressed together short carbon fibers, can be used optionally.

[0028] The above cylindrical reactor may be enclosed by a housing made of quartz or other materials that are relatively permeable to induction heating and resistant to high temperatures. This housing may show a double wall and can be cooled by a cooling fluid such as water flowing in the gap between the two walls. Thereby, the housing can maintain its structural properties even when exposed to high temperatures.

[0029] The cylindrical reactor as described in the above non-limiting examples is provided for illustrative purposes only, and long downtimes are required for preventive maintenance operations that may become necessary due to the accumulation of deposited material on the inner surface of the reaction chamber. This inner surface includes the surface of disposable or removable parts, for example, those used to rotate, support, and align the substrate and / or to improve the hydrodynamics inside the reaction chamber (directing the flow of the carrier gas, precursor gas, and exhaust gas).

[0030] In one aspect, the present invention relates to a reaction chamber for the epitaxial deposition of a semiconductor film on a substrate, (a) an essentially hollow susceptor casing extending along the longitudinal direction (x) and characterized by an inner surface and an outer surface, (b) a removable reaction part having an inner surface and an outer surface, interconnected or connectable to each other, and including at least four walls extending along the longitudinal direction. The reaction part is also characterized by two open or partially open sides, an upstream side and a downstream side. These sides are parallel to the cross-section (yz) perpendicular to the above longitudinal direction.

[0031] When using the expression "mutually connected", it means that one or more of at least four walls are integral (e.g., they can be integrally manufactured) or can be joined together via permanent or releasable means (e.g., they can be permanently joined by welding or can be removably connected by a mechanical interlocking system, rivets, or screws).

[0032] The removable reaction part may have a box-shaped configuration in which the four walls are basically parallel in the longitudinal direction. However, they may also taper slightly towards the upstream or downstream side. The cross-section of each wall in the cross-section may present a straight contour, or may be curved, or may be bent.

[0033] For example, the reaction chamber may exhibit an oval shape.

[0034] One of the four walls of the reaction part is a bottom wall provided with a receiving area adapted to receive a substrate holder. The side (upstream or downstream) of the reaction part can be completely openable or can be characterized by an upstream wall and / or a downstream wall.

[0035] In any case, the upstream side is provided with an upstream opening suitable for receiving the flow of carrier gas and precursor gas for epitaxial deposition. Similarly, the downstream side is provided with a downstream opening suitable for sending out the flow of exhaust gas. These openings can occupy the entire upstream / downstream side or can be holes crossing the corresponding upstream wall and / or downstream wall.

[0036] The reaction part according to the present invention is mechanically connected to the sensitive casing by releasable coupling means, which can be used to support and / or fix and / or align the reaction part with respect to the sensitive casing. The reaction part and the releasable coupling means are adapted to withdraw the reaction part from the sensitive casing or insert it into the sensitive casing.

[0037] This makes it unnecessary to reach inside the reactor machine from the outside, or to move the entire reactor and the sensitive elements outside the machine, and enter its inner surface, and any internal parts and components, if present, and expose them to air, enabling the reaction section to be easily removed and replaced.

[0038] The sensitive casing is adapted to be heated by induction, and for this effect, it can advantageously be made of graphite. The reaction section is mainly heated by the sensitive casing through irradiation from the sensitive casing.

[0039] The sensitive casing can show a hollow prismatic or cylindrical shape with a cross-section that is polygonal, circular, oval, or elliptical in cross-section. A basically circular cross-section can advantageously allow for a uniform heat distribution.

[0040] The sensitive casing can advantageously be open on one or both sides of the cross-section (yz) to facilitate access to the reaction section. The opening can advantageously be closed with a heat-insulating lid during operation.

[0041] To further adapt the heat irradiation profile, as considered in FIGS. 5, 6, and 7, the sensitive casing can show a variable thickness either in the longitudinal direction (x) and / or in the cross-section (yz).

[0042] In another embodiment of the present invention, the four walls of the reaction section comprise a top wall and two side walls. Either the top wall or the bottom wall can be beneficially connected to the two side walls, as well as upstream and downstream, via releasable coupling means. This embodiment allows for easy access to the inner part of the chamber (the disposable graphite part and / or the inner surface of the wall) for maintenance and / or replacement.

[0043] In another embodiment of the present invention, the releasable coupling means is a non-permanent mechanical interlocking or fastening mechanism such as a hook and loop mechanism, a snap fastener, or any other male-female fastening / joining means suitable for quick and easy release.

[0044] In another embodiment of the present invention, the inner surface of the sensitive casing may be provided with grooves or protrusions adapted to support, position, and / or removably fix the reaction part.

[0045] The reaction part may also advantageously be provided on its outer surface with protrusions or grooves adapted to releasably engage with the grooves or protrusions on the inner surface of the sensitive casing through a non-permanent mechanical interlocking or fastening mechanism. Such mechanisms include, inter alia, any joint having a releasable, i.e., non-permanent, connection shape, such as a mechanism where the protruding part is adapted to latch onto a corresponding recess or hoop, including any mechanism such as a hook and loop mechanism, a snap fastener, etc.

[0046] In another embodiment, the top and bottom walls of the reaction part of the present invention can be made of graphite, but the side walls and / or the upstream and downstream sides when only partially open are made of graphite or silicon carbide.

[0047] Advantageously, all the walls of the reaction chamber can be made of graphite, but the inner surface of the reaction part may be entirely or partially covered or coated with SiC, TaC, or other materials to protect the graphite part during deposition or cleaning operations.

[0048] According to yet another embodiment, the reaction section further comprises a removable cover of heat insulating material located above the downstream opening, aligned with the downstream opening either wholly or partially, and provided with at least one opening suitable for delivering the exhaust gas flow. The cover opening and the downstream opening may optionally be further adapted to allow insertion and extraction of the substrate holder. The removable cover may further be coupled to at least one of the four walls via releasable fastening means.

[0049] According to another embodiment, the reaction section may further comprise an upstream heat insulating element, optionally detachable, positioned on the top wall and / or the bottom wall at a distance L ≤ 20% from the upstream side, where L is the minimum distance between the downstream side and the upstream side in the longitudinal direction.

[0050] The heat insulating material used in the above embodiments may be a carbonaceous, preferably porous material. For example, a carbon composite made from short cut carbon fibers, optionally interconnected in a matrix or pressed together, may be advantageously selected. The surface of these materials may be coated to improve their density and reduce the risk of debris resulting from separating fibers or other sections.

[0051] According to another embodiment, the reaction section further comprises a first transition part, optionally detachable, positioned on the upstream opening adapted to be coupled to the precursor gas liner.

[0052] In a further embodiment, the reaction section of the reaction chamber according to the invention may further comprise engaging means such as indentations, protrusions, hooks, loops, or slides adapted to be mechanically coupled to the end effector of an automatic handling machine so as to be withdrawn / inserted integrally and automatically from / into the sensitive casing. Thereby, the removal of the reaction section can be upgraded from manual means to automated means.

[0053] The reaction section according to the present invention is compact and adapted to be handled. For example, the reaction section can be 200 mm to 400 mm × 30 mm to 50 mm in cross-section and 200 mm to 500 mm in the longitudinal direction. The reaction section can typically have a weight of 2 kg to 10 kg, preferably 2.5 kg to 6 kg. The susceptor casing may be 200 mm to 500 mm in the longitudinal direction and may have a diameter in the transverse direction and / or its main length of 210 mm to 450 mm.

[0054] The reaction section includes a plurality of inner linings adapted to be fastened around the receiving area to control the exposure of the precursor gas of the substrate holder to the flow and / or protect the exposed bottom surface of the reaction section from parasitic accumulation. These inner linings can be easily collected from the reaction section during preventive maintenance for cleaning or replacement. These inner linings are made of graphite and coated with SiC and / or TaC.

[0055] According to a second aspect, the present invention relates to a reactor suitable for epitaxial deposition of a semiconductor film on a substrate, comprising: (i) at least one reaction chamber according to any of the above embodiments; (ii) a thermal insulation system enclosing the reaction chamber, including one or more thermal insulation components; and (iii) a liner suitable for directing the process gas at the reaction section and connected to the reaction section using releasable coupling means.

[0056] Advantageously, the reactor may include 1 to 8 reaction chambers, preferably 2 to 6 reaction chambers.

[0057] The liner may include a (second) transition component that can be coupled to a first transition component attached to the upstream side of the reaction section.

[0058] One or more insulation components should be made of a rigid material suitable for withstanding the high temperatures reached by the reactor. For example, but not exclusively, they can be made of a rigid carbonaceous material (such as a material containing short cut carbon fibers, optionally interconnected in a matrix or pressed together).

[0059] All surfaces of the insulation components can advantageously be coated to improve their tightness and to reduce the formation of debris that can result from the separation of fibers or other particles from the bulk insulation material. The coating used can be a graphite-based coating.

[0060] The reactor can advantageously include an enclosure such as a double-walled quartz tube suitable for having a flow of cooling fluid in the gap between its two walls. Other elements typically used in a reactor as described above can be present, as will be apparent to those skilled in the art.

[0061] One or more induction coils or capacitors can be located outside the reactor to heat the susceptor casing and, directly or indirectly, the reaction part of each reaction chamber.

[0062] In a third aspect, the invention relates to an assembly for moving and handling the reaction part for preventive maintenance operations of the reactor. The assembly comprises the reactor, the transfer chamber, and the unit handling chamber described above.

[0063] The transfer chamber is characterized by a first opening provided with a first shut-off valve adapted to receive or send out the reaction part from / to the reactor via one or more automated machines or via manual means, and a second opening provided with a second shut-off valve.

[0064] The unit handling chamber is installed in communication with the transfer chamber through the second opening and the second shut-off valve and is adapted to receive or send out the reaction part from / to the transfer chamber via electromechanical means.

[0065] The unit handling chamber is adapted to regulate the reaction section and is provided with a resealable access path such as a door, hatch, port hole, or valve suitable for removal and insertion of the reaction section by an operator or by automated handling means.

[0066] When using the term "regulate", it means various operations or cycles suitable for preparing the reaction section prior to insertion into the reactor. Additionally or alternatively, the operations or cycles are adapted to make the reaction section suitable for access by an operator or machine and to be removed from the assembly for removal or cleaning of parts of the reaction section. Possible cycles may include creating a vacuum of less than 10 millibars and performing a refill under an inert gas such as argon, nitrogen, helium, or xenon. In addition to or instead of inert gas refill, the reaction section may be purged with an inert gas, with argon being the preferred inert gas. Alternative cycles suitable for performing on a new / clean reaction section prior to insertion into the reactor may include a heating step and a vacuum degassing step (in this case, the vacuum is preferably less than 1 millibar, even more preferably less than 10 -3 millibars).

[0067] In the assembly according to the present invention, the transfer chamber may also advantageously be adapted to receive or send out the substrate holder from / to the reactor through a first opening via electromechanical means. The assembly according to this embodiment may optionally and advantageously comprise a load lock chamber installed in communication with the transfer chamber through a third opening and a third shut-off valve.

[0068] Thus, the load lock chamber can receive or send out the substrate holder from / to the transfer chamber through the third opening via electromechanical means.

[0069] The load lock chamber may further comprise a resealable access path suitable for removal and insertion of the substrate holder by an operator or by automated handling means.

[0070] 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 with the reaction part to extract it from the sensitive casing and insert it into the transfer chamber, and vice versa. The first end effector may be advantageously adapted to couple through the reaction part and, if present, engaging means present on the reaction part.

[0071] The first automated handling machine may also optionally be provided with a second end effector adapted to engage with the substrate holder to insert or extract it into / from the reaction part.

[0072] These embodiments enable automated handling of both the reaction part and the substrate.

[0073] In a fourth aspect, the invention relates to a method for preventive maintenance of a reaction part of a previously disclosed reactor, comprising: (a) releasing the liner from the reaction part; (b) decoupling the reaction part from the sensitive casing; (c) integrally withdrawing the reaction part from the sensitive casing and then from the reactor via manual or automated means.

[0074] Advantageously, step (c) comprises: (c1) withdrawing the reaction part from the sensitive casing and then from the reactor via a first automated handling machine; (c2) installing the reaction part into the transfer chamber through a first opening via the first automated handling machine or a second automated handling machine. (c3) It may be carried out according to a sub-step of transporting a reaction part in a unit handling chamber installed in communication with a transport chamber through a second opening and valves for adjustment and entry.

[0075] Therefore, in the reaction chamber design of the present invention, a reactor and an assembly adapted to easily access the reaction part for preventive maintenance operations and to remove or insert the reaction part from / to a sensitive casing and the reactor through manual or automated means are fabricated, and before cleaning, an adjustment operation is carried out without exposing the chamber to air, thereby ensuring safe working conditions for the operator handling the reaction part thereafter. By this process, the preventive maintenance time can be shortened by 70%.

[0076] Furthermore, through possible automation of the process and specific use of connected chambers (transport chamber and unit handling chamber), it is possible to avoid the simultaneous presence of an operator during the movement of the reaction part and / or the assembly within the reactor.

[0077] According to a fifth aspect, the present invention relates to the use of the reactor described above for hot-wall cross-flow epitaxial deposition of silicon carbide or gallium nitride.

[0078] (Description of the Drawings) The examples presented in this specification do not mean the actual form of any specific material, structure, or device, but are merely idealized representations used to describe embodiments of the present disclosure. Specifically, they are not intended to limit the scope of aspects and implementations in any way. In fact, for the sake of brevity, conventional manufacturing, related, preparation, and other functional aspects of the system may not be described in detail. Furthermore, the connection lines shown in the various figures 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 the actual system and / or may not exist in some embodiments.

[0079] Figure 1 schematically shows a cross-section (yz) of an embodiment of the reaction chamber (100) of the present invention. The reaction chamber is suitable for the epitaxial deposition of a semiconductor film on a substrate and includes a hollow sensitive casing (200) and a reaction section (300).

[0080] The sensitive casing extends along a longitudinal direction (x) perpendicular to the cross-section. The sensitive casing is characterized by an inner surface (250) and an outer surface, and houses a removable reaction section (300).

[0081] The reaction section (300) has a box-like shape. This includes four walls (310, 320, 330, 340) that extend along the longitudinal direction. The four walls include a top wall (320), two side walls (330, 340), and a bottom wall (310). The latter is provided with a receiving area (311) adapted to receive a substrate holder (315).

[0082] The reaction section further includes an upstream side (not shown) and a downstream side (360) parallel to the cross-section (yz). In this embodiment, the downstream side is a wall provided with a downstream opening (361) suitable for receiving the flow of carrier gas and precursor gas for epitaxial deposition. The upstream side is completely open and corresponds to an upstream opening indicated by a dashed line (351). The upstream opening is suitable for sending out the flow of exhaust gas. The reaction section is mechanically connected to the sensitive casing via releasable coupling means (331, 332). This reaction section can be movable integrally with respect to the sensitive casing, thereby facilitating its insertion and extraction from / to the sensitive casing and shortening the time required for preventive maintenance operations.

[0083] To further facilitate preventive maintenance operations, the top wall (320) is connected to the two side walls and the upstream and downstream sides via releasable coupling means (321) such as a male-female interlocking mechanism.

[0084] The handling of the reaction part can be facilitated and automated by providing engagement means such as depressions (371, 372) adapted to be coupled to the end effector of the automatic handling machine on this reaction part. The end effector may have a shape like a fork provided with two prongs adapted to be coupled to the depressions (371, 372).

[0085] FIG. 2 shows a schematic isometric view of the sensitive casing (panel I) and the reaction part (panel II) of the reaction chamber (100) of FIG. 1.

[0086] Panel I of FIG. 2 shows a sensitive casing (200) having a hollow cylindrical shape and extending along a longitudinal direction (x) perpendicular to the cross section (yz). The sensitive casing is characterized by an inner surface (250) and an outer surface and is adapted to accommodate the removable reaction part (300) of panel II.

[0087] The sensitive casing is provided with protrusions (251, 252) extending from its inner surface and adapted to support the reaction part and position it on the above-mentioned surface. The reaction part can slide onto these protrusions both inside and outside the sensitive casing. Grooves (253, 254) can be used to further guide and more accurately position the reaction part on the inner surface. These can be shaped to engage corresponding protrusions on the outer surface of the reaction part, such as the protrusions (331, 332) shown in panel II of FIG. 2, to create an interlocking system.

[0088] Panel II of FIG. 2 shows the reaction part (300) of FIG. 1 with the open upstream side (350) and the corresponding opening (351) made more visible.

[0089] FIG. 3 provides a schematic isometric view of the reaction part shown in panel II of FIG. 2 according to a second embodiment. In this case, the reaction part further comprises a removable cover (400) of heat insulating material located across the downstream side (360) and provided with one opening (401). This opening is aligned with the downstream opening (361) and is suitable for sending out the flow of exhaust gas.

[0090] The reaction section includes a first transition component (500) positioned over the upstream opening (351) and adapted to be coupled to the precursor gas liner.

[0091] FIG. 4 shows a simplified schematic view of an assembly (2000) according to an embodiment of the present invention. The assembly is designed to facilitate the movement and handling of a reaction section, such as but not limited to those illustrated in FIGS. 1 - 3, for preventive maintenance operations of the reactor. The assembly comprises a reactor (1000) coupled to a system of connection chambers (2100, 2200, 2300).

[0092] The reactor comprises a double - walled quartz tube around which an induction coil (not shown) for heating is wound. The reactor further comprises a thermal insulation system (1100) wound around the reaction chamber. The latter includes a susceptor casing (200) and a reaction section (300).

[0093] The reaction section is characterized by a first transition component (500) positioned over the upstream opening (351) and coupled to a liner (1200). The reaction section further comprises a removable cover (400) of thermal insulation material having one opening (401) located over the downstream side (360) and aligned with the downstream opening (361). The reaction section comprises engagement means (371, 372) adapted to be coupled to the end effector of an automatic handling machine (not shown).

[0094] The reactor is connectable to a system of connection chambers (2100, 2200, 2300) via a downstream drum (700). The system of chambers comprises a transfer chamber (2100) having a first partition valve (2111) and a first opening (2110) adapted to receive or deliver the reaction section from / to the reactor through the downstream drum via one or more automated machines (or, if possible to avoid, manually). The transfer chamber is also characterized by a second opening (2120) provided with a second partition valve (2121).

[0095] The system of connection chambers (2100, 2200, 2300) also comprises a unit handling chamber (2200) installed in communication with the transfer chamber through a second opening (2120) and a second shut-off valve (2121). The unit handling chamber is adapted to receive / send out reaction parts from / to the transfer chamber via electromechanical means, and is provided with a resealable access path (2210) suitable for extraction and insertion of the reaction part (300) by an operator or by automatic handling means.

[0096] The unit handling chamber may be used to adjust the reaction part before pulling it out of the assembly or before inserting it into the reactor through the transfer chamber.

[0097] The system of connection chambers (2100, 2200, 2300) also comprises a load lock chamber (2300) installed in communication with the transfer chamber through a third opening (2130) and a third shut-off valve (2131). The load lock chamber is adapted to receive / send out a substrate holder from / to the transfer chamber through the third opening via electromechanical means (not shown).

[0098] Advantageously, the assembly according to this embodiment may comprise a first automatic handling machine (not shown) provided with a first end effector suitable for engaging with the reaction part to pull it out of the sensitive casing and insert it into the transfer chamber, and vice versa.

[0099] The first automatic handling machine is also provided with a second end effector (3200) suitable for engaging with the substrate holder to insert / pull it into / out of the reaction part, thereby providing a fully automated system.

[0100] FIG. 5 schematically shows cross-sections in the longitudinal plane (xz) and the cross-sectional plane (yz) of an embodiment of the reaction chamber (100) of the present invention. The two cross-sections are shown in panels I and II respectively.

[0101] The reaction chamber includes a hollow sensitive casing (200) and a reaction section (300). The reaction section (300) has a box-like shape and includes a top wall (320), two side walls, and a bottom wall (310).

[0102] The sensitive casing is characterized by an inner surface (250) that extends along a longitudinal direction (x) perpendicular to the cross-section and has protrusions (251, 252) adapted to support and position the reaction section (300). The reaction section is provided with releasable coupling means (331, 332) configured to engage with the protrusions (251, 252).

[0103] Referring to Panel I, the sensitive casing is characterized by a non-uniform thickness along the longitudinal direction. In this case, the upper portion of the sensitive casing is characterized by a decrease in thickness corresponding to a central portion (B) along the longitudinal direction x with respect to the peripheral portion (A). This configuration will cause a higher temperature in the central portion (B) where the receiving region (not shown) is located. Note that the receiving region and the substrate holder can be substantially parallel to the horizontal plane (xy).

[0104] Naturally, there may be situations where the achieved technical effect is reversed, and in this case, the thickness of the central portion (B) can be increased with respect to the thickness of the peripheral portion (A). Adjusting the thickness of the sensitive casing along the longitudinal direction enables controlling the temperature gradient in the longitudinal (upstream - downstream) direction, i.e., the direction in which the process gas flows. This temperature gradient can affect the quality of the film deposited on the substrate, for example, from the viewpoints of thickness and doping uniformity.

[0105] Generally, it is advantageous to control the longitudinal temperature gradient of the reaction chamber according to any embodiment of the present invention by modifying the thickness of the sensitive casing in the longitudinal direction, particularly in a portion positioned corresponding to the receiving region. The portion with variable thickness may be limited to the upper chord and / or lower chord of the sensitive casing.

[0106] Referring to Panel II, the sensitive casing is characterized by a non-uniform thickness in cross-section. Specifically, one section of the sensitive casing is thicker at an angle composed of 0 to θ, and the above angle is preferably formed in the direction y passing through the center of the reaction part and is symmetric with respect to the xz plane.

[0107] In this case, the thickness variation is configured to control the temperature gradient in the y direction, that is, the direction perpendicular to the longitudinal direction, and within the horizontal plane. In fact, a small gradient in this direction can make it possible to reduce the possibility of sublimation of the SiC film deposited on the substrate holder. This undesirable effect may occur when the periphery of the substrate in the y direction is very hot, which can cause trace residues and quality problems.

[0108] The embodiments discussed in relation to Panel I and Panel II can be implemented simultaneously or separately without departing from the scope of the present invention.

[0109] FIG. 6 schematically shows a cross-section of a hollow sensitive casing (200) in a cross-section (yz) according to an embodiment of the reaction chamber of the present invention.

[0110] The sensitive casing basically shows a cylindrical shape and extends along the longitudinal direction (x) perpendicular to the cross-section.

[0111] The sensitive casing is characterized by an inner surface (250) provided with protrusions (251, 252) adapted to support and position the reaction part.

[0112] Even if there are protrusions (251, 252), the sensitive casing has a first average thickness t 1 and a second average thickness t 2 >t 1 in the cross-section. Generally, it is advantageous for t 1 to show a thickness increased by 20% to 80%, preferably 30% to 60%, with respect to t 2 .

[0113] Average thickness t 2 The portion of the susceptive casing having it is positioned symmetrically in the cross-section (yz) with respect to the vertical direction z, forming an angle of α to θ in the horizontal direction y, where α = -45 degrees to 0 degrees, and θ = 5 degrees to -45 degrees.

[0114] FIG. 7 schematically shows a cross-section of a hollow susceptive casing (200) in a cross-section (yz) according to an embodiment of the reaction chamber of the present invention.

[0115] The susceptive casing basically shows a cylindrical shape and extends along the longitudinal direction (x) perpendicular to the cross-section (yz). To reduce heating corresponding to the central portion of the reaction portion (not shown), the casing features an opening on the upper portion of the susceptor.

[0116] Alternatively, it should be understood that the casing may show a plurality of openings that may be symmetric with respect to a horizontal plane (xy) parallel to the substrate to be processed. Advantageously, the openings may be located in a substantially central portion of the susceptive casing in the longitudinal direction.

[0117] FIG. 8 shows an embodiment of a reaction chamber (100) according to the present invention presenting a cross-section in a cross-section (yz) perpendicular to the longitudinal direction.

[0118] The reaction chamber includes a hollow susceptive casing (200) and a reaction portion (300). The susceptive casing extends along the longitudinal direction and features an inner surface (250) with protrusions (251, 252) adapted to support and position the reaction portion (300). The reaction portion is provided with releasable coupling means (331, 332) configured to engage with the protrusions (251, 252).

[0119] Both the susceptive casing and the reaction portion feature an oval cross-section in the cross-section. The similar flat shape of both elements improves heat transfer between the susceptive casing and the reaction portion by irradiation.

[0120] The reaction section (300) features a top wall (320), two curved side walls (330, 340), and a bottom wall (310). The bottom wall has a receiving area (311) adapted to fixedly rotate a substrate holder (315) that supports a substrate.

[0121] The subject matter of the present disclosure includes not only all novel and non-obvious combinations and sub-combinations of the various processes, systems, and configurations disclosed herein, as well as other features, functions, operations, and / or characteristics, but also all equivalents thereof.

[0122] In the specification and claims of this application, the term "comprise" and its variations such as "comprising" and "comprises" do not exclude the presence of other additional elements, components, or steps.

[0123] The discussion of documents, acts, materials, devices, articles, etc. is included in the text only for the purpose of providing a background to the present invention, but this material or a part thereof should not be understood as constituting general knowledge in the field of the present invention prior to the priority date of each of the claims appended to this application.

Claims

1. A reaction chamber (100) for epitaxial deposition of a semiconductor film on a substrate, comprising: an essentially hollow sensitive casing (200) extending along a longitudinal direction (x) and characterized by an inner surface (250) and an outer surface; a removable reaction section (300) having an inner surface and an outer surface, and including (i) four walls (310, 320, 330, 340) extending along said longitudinal direction, and (ii) upstream and downstream sides (350, 360) parallel to a transverse plane (yz) perpendicular to said longitudinal direction; A reaction chamber, the four walls of which comprise a bottom wall (310) provided with a receiving area (311) adapted to receive a substrate holder, the upstream side having an upstream opening (351) suitable for receiving a flow of carrier gas and precursor gas for the epitaxial deposition, and the downstream side having a downstream opening (361) suitable for delivering a flow of exhaust gas, the reaction chamber being mechanically connected to the sensitive casing via releasable coupling means (331, 332) and movable integrally with respect to the sensitive casing.

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

3. 3. The reaction chamber of claim 1 or 2, wherein the releasable coupling means is a non-permanent mechanical interlocking or fastening mechanism.

4. The reaction chamber according to any one of claims 1 to 3, wherein the inner surface of the sensitive casing is provided with grooves or protrusions (251, 252, 253, 254) adapted to support, position and / or releasably secure the reaction portion on the inner surface.

5. 5. The reaction chamber of claim 4, wherein the reaction section is provided on its outer surface with protrusions or grooves (331, 332) adapted to releasably engage with the grooves or protrusions on the inner surface of the susceptible casing through a non-permanent mechanical interlocking or fastening mechanism.

6. 6. The reaction chamber of claim 1, wherein the reaction section further comprises a removable cover (400) of insulating material located over the downstream side and provided with at least one opening (401), said opening being fully or partially aligned with the downstream opening and suitable for delivering a flow of exhaust gas.

7. 7. The reaction chamber of claim 1, wherein the reaction section further comprises a first transition piece (500) positioned on the upstream opening and adapted to be coupled with a precursor gas liner, the first transition piece being optionally removable.

8. 8. The reaction chamber according to any one of claims 1 to 7, wherein the reaction section further comprises an upstream insulating element (600), optionally removable, positioned on the top wall and / or the bottom wall at a distance L of ≦20% from the upstream side, L being the minimum distance between the downstream side and the upstream side in the longitudinal direction.

9. The reaction chamber of any one of claims 1 to 8, wherein the top and bottom walls of the reaction section are made from graphite and the side walls are made from graphite or silicon carbide.

10. 10. The reaction chamber of claim 9, wherein the sidewalls are made of graphite and the inner surface of the reactor is covered or coated, in whole or in part, with SiC or TaC.

11. The reaction chamber according to any one of claims 1 to 10, wherein the susceptible casing is made from graphite.

12. 12. The reaction chamber according to any one of claims 1 to 11, wherein said sensitive casing presents an essentially hollow prismatic or cylindrical shape in said transverse plane (yz) with a polygonal, circular, oval or elliptical cross section.

13. The reaction chamber according to any one of claims 1 to 12, wherein said susceptible casing is open on at least one side of said transverse plane (yz).

14. The reaction chamber according to any one of claims 1 to 13, wherein the susceptibility casing is characterized by a variable thickness in the longitudinal direction and / or in the transverse plane (yz).

15. The reaction chamber according to any one of claims 1 to 14, further comprising engagement means (371, 372) adapted to couple with an end effector of an automatic handler so that the reaction part is pulled out / inserted integrally from / into the sensitive casing.

16. A reactor (1000) suitable for epitaxial deposition of a semiconductor film on a substrate, comprising: At least one reaction chamber (100) according to any one of claims 1 to 15, an insulation system (1100) including one or more insulation components enclosing the at least one reaction chamber; a liner (1200) suitable for directing process gas in the reaction portion of the at least one reaction chamber and connected to the reaction portion by means of a releasable coupling means.

17. An assembly (2000) for moving and handling a reaction section for preventive maintenance operations of a reactor, comprising: The reactor (1000) according to claim 16; a transfer chamber (2100) including a first opening (2110) provided with a first gate valve (2111) adapted to receive or deliver said reaction parts from / to said reactor via one or more automated machines or via manual means, and a second opening (2120) provided with a second gate valve (2121); a unit handling chamber (2200) located in communication with the transfer chamber through the second opening (2120) and the second gate valve (2121) and adapted to receive or deliver the reaction parts from / to the transfer chamber via electromechanical means; An assembly, wherein the unit handling chamber is adapted to accommodate the reaction parts and is provided with a resealable access (2210) suitable for the removal and insertion of the reaction parts by an operator or by automated handling means.

18. 18. The assembly of claim 17, wherein the transport chamber is further adapted to receive or deliver a substrate holder from / to the reactor through the first opening via motorized mechanical means, and the assembly further comprises a load lock chamber (2300) installed in communication with the transport chamber through a third opening (2130) and a third gate valve (2131), the load lock chamber being adapted to receive or deliver the substrate holder from / to the transport chamber via motorized mechanical means through the third opening.

19. 19. An assembly as described in claim 17 or 18, further comprising a first automatic handler (3000) provided with a first end effector (3100) suitable for engaging the reaction portion to extract it from the susceptibility casing and insert it into the transport chamber, and vice versa.

20. 20. The assembly of claim 19, wherein the first automated handler is provided with a second end effector (3200) suitable for engaging a substrate holder to insert or remove it from the reaction section.

21. 16. A method for preventative maintenance of a reaction chamber according to claim 15, comprising the steps of: (a) releasing the liner (1200) from the reaction chamber (300); (b) decoupling the reaction portion (300) from the susceptor casing (200); (c) withdrawing said reaction section in one piece from said susceptibility casing and then from said reactor via manual or automated means.

22. Step (c) further comprises the additional steps of: (c1) extracting the reaction part from the susceptor casing and then from the reactor via a first automated handling machine (3000); (c2) placing the reaction unit in a transfer chamber (2100) through a first opening (2110) via the first automated handler or a second automated handler; The method of claim 21, further comprising: (c2) transporting the reaction part in a unit handling chamber (2200) that is placed in communication with the transport chamber through a second opening (2120) and an adjustment and entry valve (2121).

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