Reaction chamber assembly

Abstract

The present invention relates to the field of reactors for the epitaxial growth of films on substrates.SOLUTION: A reaction chamber assembly of a reactor for epitaxial deposition of semiconductor films on at least two substrates, the reaction chamber assembly comprising: (a) an enclosure; (b) at least two casings contained within the enclosure; (c) at least two deposition units; and (d) an isolation system. Each casing houses at least one deposition unit. Each deposition unit is provided with at least one receiving area adapted to receive a substrate holder and suitable for epitaxial deposition of a semiconductor film on a substrate. The insulation system comprises an intermediate insulation element positioned between the at least two casings.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to the field of reactors for the epitaxial growth of films on substrates. [Background technology]

[0002] Semiconductor films produced by epitaxial growth, also known as epilayers, are formed by deposition within a reaction chamber in a reactor. The deposited material may be the same as the substrate or may contain a different semiconductor with specific desired qualities. Epitaxial growth techniques allow for control over the crystalline structure formed on the substrate and improved surface characteristics of the epilayer, making them suitable for the fabrication of highly complex microprocessors and memory devices.

[0003] Typically, the reaction chamber is heated to a desired temperature prior to film deposition, and the temperature is then maintained substantially constant throughout the deposition process. To this effect, an isolation system is used to reduce the energy required to achieve and maintain the nominal temperature of the deposition process.

[0004] An SiC (silicon carbide) industrial epitaxial growth apparatus comprises a reactor that houses a reaction and deposition chamber where the deposition process occurs.

[0005] The reaction chamber and deposition chamber often comprise a single deposition region, i.e., the space where epitaxial reaction and deposition take place (referred to herein as a "deposition unit"). This region can be configured for either epitaxial deposition on a single substrate or simultaneous deposition on multiple substrates. Thus, the deposition processes are defined as single-wafer or batch processes, respectively.

[0006] In single wafer processes such as those described in WO 2004 / 053187 A1, deposition conditions can be precisely controlled because the dimensions of the deposition area are relatively small and the resulting deposition quality can be very good. However, throughput is inherently limited by the single wafer approach.

[0007] Conversely, batch processes allow for improved throughput compared to their single-wafer counterparts, but are detrimental to film quality due to the inability to precisely and independently control the temperature and rotation speed of multiple substrates, which also results from the increased size of the deposition area, as the latter must accommodate multiple substrates simultaneously.

[0008] Alternatively, some reactors feature multiple reaction chambers, each hosting one deposition region. These designs increase throughput at the expense of a larger footprint on the manufacturing floor. These cumbersome solutions therefore increase the cost of ownership.

[0009] Furthermore, during the epitaxial deposition process, the deposition area may be subject to parasitic deposition. This undesirable phenomenon is particularly prevalent in silicon carbide epitaxy due to the material's superior hardness, which makes removal extremely difficult, especially compared to silicon or other common silicon-based compounds. This leads to frequent maintenance and replacement of components, requires reactor shutdowns for maintenance work, and impacts throughput in both single-wafer and batch-type processes due to the reaction chamber's exposure to air during the process.

[0010] It would therefore be desirable to provide a reaction chamber assembly designed to process at least two substrates at once in separate deposition zones without compromising deposition quality and in a compact design.

[0011] It would further be desirable to provide a reaction chamber assembly in which each deposition zone is integrally removable for easy preventative maintenance thereon.

[0012] Additionally, it would be desirable to provide a reactor that is adapted to provide different heat to different deposition units. Summary of the Invention [Means for solving the problem]

[0013] This summary is provided to introduce some concepts in a simplified form that are described in more detail below in the detailed description of exemplary embodiments of this disclosure. 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.

[0014] SUMMARY OF THE INVENTION It is an object of the assembly of the present invention to provide a reaction chamber assembly and reactor for epitaxial deposition of semiconductor films on substrates that overcomes the shortcomings of the prior art.

[0015] In particular, it is an object of the present invention to provide a reaction chamber assembly adapted to process at least two substrates at a time in separate deposition units without compromising deposition quality and without presenting a compact design.

[0016] Another object of the present invention is to provide a reaction chamber assembly in which each deposition unit is removable as a unit for simple preventative maintenance.

[0017] Another object of the present invention is to provide a reactor adapted to provide different heat to different deposition units.

[0018] The above-mentioned main object is achieved by the invention as set forth in the appended claims, which form an integral part of this specification.

[0019] It should be noted that the use of reference signs in the claims does not limit their scope: their sole purpose is to make the claims easier to understand. [Brief explanation of the drawings]

[0020] The examples presented in this disclosure are not meant to be actual representations of any particular materials, structures, or devices, but are merely idealized representations used to describe embodiments of the present disclosure.

[0021] [Figure 1] 1 is an orthographic three-dimensional view of a reaction chamber assembly according to an embodiment of the present invention. [Figure 2] FIG. 2 is a plan view of a reactor section in cross-section (yz) according to an embodiment of the present invention. [Figure 3] FIG. 2 is a plan view of a reactor section in cross-section (yz) according to an embodiment of the present invention. [Figure 4] 1 is an orthographic three-dimensional view of a deposition unit according to the invention; [Figure 5] 1 is an orthographic three-dimensional view of a deposition unit according to the invention; [Figure 6] FIG. 2 is an orthographic three-dimensional view of a section of a reactor in the longitudinal direction, according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0022] While certain specific embodiments and examples are disclosed below, it will be understood by those skilled in the art that the scope of the invention extends beyond the specifically disclosed embodiments and / or uses of the invention, and obvious variations and equivalents thereof. Accordingly, it is not intended that the scope of the disclosed invention should be limited by the specific disclosed embodiments described below.

[0023] Reference will now be made to the drawings in which like reference numbers identify similar structural features or aspects of the present disclosure.

[0024] It will be understood that elements in the figures are illustrated for simplicity and clarity. In particular, some elements may be omitted or may not necessarily be drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help improve understanding of the illustrated embodiments of the present disclosure.

[0025] According to a first aspect, the present invention relates to a reaction chamber assembly 1 of a reactor 2 for epitaxial deposition of semiconductor films on at least two substrates.

[0026] The reaction chamber assembly 1 comprises an enclosure 3 and at least two casings 4 housed within the enclosure.

[0027] The reaction chamber assembly 1 further comprises at least two deposition units 5 and an insulation system.

[0028] Specifically, at least two deposition units 5 are arranged such that each casing 4 houses at least one deposition unit 5 .

[0029] Each deposition unit 5 is provided with at least one receiving area 6 adapted to receive a substrate holder 7 and suitable for epitaxial deposition of a semiconductor film on the substrate.

[0030] The insulation system comprises an intermediate insulation element 11 positioned between at least two casings 4 .

[0031] Thus, at least two casings are positioned facing each other and at least an intermediate insulating element 11 is positioned between them.

[0032] Advantageously, the intermediate insulating element 11 may make it possible to thermally separate at least two casings 4 from one another.

[0033] For example, the intermediate insulating element 11 may be made of a porous carbonaceous material.

[0034] For example, carbon composites made from short cut carbon fibers, optionally interconnected or pressed together in a matrix, have been observed to work particularly well in the practice of the present invention.

[0035] Advantageously, the reaction chamber assembly according to the present invention allows for the processing of at least two substrates at once.

[0036] The presence of at least two deposition units, each dedicated to one or more substrates, may provide a particularly compact design, with all deposition units housed in one and the same enclosure.

[0037] According to one embodiment, the deposition unit 5 is provided with one receiving area 6 adapted to receive a substrate holder 7 designed to hold a single substrate.

[0038] Advantageously, the present invention according to this embodiment makes it possible to provide deposition quality comparable to single wafer reactors with increased throughput.

[0039] According to one embodiment, the deposition unit 5 comprises a container, optionally comprising a removable lid 16 releasably connected to the container.

[0040] For example, the vessel defining the exterior of the deposition unit may provide an essentially closed surface around the receiving area, except for a certain number of openings. The openings may be through-holes designed for the insertion and removal of substrate holders and / or the inflow and outflow of gases. Furthermore, they may be designed for monitoring systems or for the insertion of mechanical / automated systems. In a non-limiting example, the vessel may have a box-like shape, as shown in Figures 1-6.

[0041] Advantageously, the vessel can provide a closed space of relatively small size, so that all relevant parameters of the epitaxial deposition (such as temperature and pressure) can be easily controlled and kept uniform over the receiving area, thereby improving the quality of the deposited film.

[0042] Advantageously, the removable lid allows for easy access to the consumable parts surrounding the receiving area of ​​the deposition unit for preventive maintenance work. To facilitate access, the removable lid may be a removable wall of the container and may be positioned on the opposite side of the receiving area. The removable lid may be secured and released from the rest of the container via a non-permanent mechanical interlocking or fastening mechanism, such as a hook and loop mechanism, a snap fastener, or any other suitable male-female fastening / jointing means for quick and easy fastening and release.

[0043] According to one embodiment, each deposition unit 5 is mechanically connected to the casing 4 via releasable coupling means 10 and is movable integrally with respect to the casing 4 .

[0044] Advantageously, this embodiment makes it possible to access areas subject to parasitic deposition for cleaning in a simple manner by simply removing the relatively small deposition unit from the reactor, either manually or via automated means. In principle, the design makes it possible to carry out this operation without exposing the deposition unit to air.

[0045] By great advantage, this design avoids the need to displace a more cumbersome reaction chamber assembly and / or require an operator to enter the reactor machine to access the associated parts for preventative maintenance.

[0046] According to one embodiment, the releasable coupling means 10 is a non-permanent mechanical interlocking, support, or fastening mechanism. Non-limiting examples of releasable coupling means include grooves or protrusions formed on the deposition unit (particularly the container) and / or the casing, and suitable for supporting, releasably securing, and / or orienting the deposition unit on / within the casing. See, for example, Figures 1 and 3.

[0047] According to one embodiment, the deposition unit 5 comprises (a) an inlet 8 suitable for introducing a gas flow into the deposition unit, and (b) an outlet 9 suitable for discharging the gas flow out of the deposition unit 5.

[0048] Inlet 8 and outlet 9 may comprise or consist of one or more openings formed on the vessel of deposition unit 5 to allow entry of precursor, process, cleaning, and exhaust gases, respectively.

[0049] The inlet 8 may be connected or releasably connected to a transition piece 15 positioned above the upstream opening of the vessel and optionally adapted to couple with a precursor gas liner 17 .

[0050] The transition piece 15 may optionally be removable to facilitate removal of the deposition unit 5 .

[0051] The outlet 9 may also be connected to an exhaust gas collecting element, removably or permanently attached to the downstream opening and optionally provided with a filter.

[0052] According to one embodiment, the insulation system comprises at least one insulating cover 12 adapted to fully or partially cover at least one casing 4, without prejudice to the fact that both may be covered simultaneously. The insulation system may comprise at least three (or four) insulating covers 12, which may be movable relative to one another. For example, if the reaction chamber assembly extends along the longitudinal direction (x), two insulating covers 12 may extend along the longitudinal direction (x) as shown in FIG. 1, and the two insulating covers 12 may be arranged on either side of a (yz) plane perpendicular to (x), as shown in FIG. 2 (showing only one insulating cover).

[0053] Advantageously, this embodiment allows the reaction chamber assembly to be thermally insulated from its surroundings, thereby increasing its heating efficiency and reducing operating costs.

[0054] For example, the insulating system or insulating cover 12 may be made of a porous carbonaceous material.

[0055] For example, carbon composites made from short cut carbon fibers, optionally interconnected or pressed together in a matrix, have been observed to work particularly well in the practice of the present invention.

[0056] According to one embodiment, the casing 4 is essentially hollow and extends along a longitudinal direction (x).

[0057] Thus, according to this embodiment, the casing features an inner and outer surface, the inner surface may easily include grooves or protrusions or stands adapted to engage with grooves, protrusions, hooks, catches or fasteners on the deposition unit to collectively function as a connecting means.

[0058] Advantageously, the hollow casing design is lighter than bulk designs, easier to handle, and may provide an improved heating profile for the array unit.

[0059] According to one embodiment, the casing 4 has an essentially hollow prismatic, cylindrical or semi-cylindrical shape with a polygonal, circular, semi-circular, oval or elliptical cross section in a transverse plane (yz) perpendicular to the longitudinal direction (x).

[0060] The inventors have observed that the use of two casings having semicircular cross sections in the transverse plane (yz), with each casing positioned with its flat side facing the other, can advantageously provide a compact design and produce a desirable uniform thermal profile within the deposition unit.

[0061] Examples of the above designs are provided in Figures 1, 2, 3, and 6.

[0062] According to one embodiment, enclosure 3 is made of a non-susceptible material (i.e., substantially transparent or transparent to electromagnetic induction heating), such as quartz, and is optionally cooled with a cooling fluid, such as water. For example, enclosure 3 may be a double-walled quartz tube with one or more cooling fluid inlets and outlets to allow fluid to flow within the gap between the tubes.

[0063] Advantageously, a cooled, double-walled quartz enclosure effectively shields the surrounding environment from the heat generated by the reaction chamber assembly during operation. For example, in a silicon carbide reactor, temperatures inside the reaction chamber assembly can be in the range of 1200°C to 1700°C, and therefore it is desirable to protect the environment from the effects of such temperatures. The use of quartz is particularly appreciated because it is transparent to induction heating means and does not impede visual inspection of the casing.

[0064] According to one embodiment, each casing 4 is made of a sensitive material suitable for being heated via the induction system 13. Preferably, the sensitive material is graphite.

[0065] 1 to 6, the reaction chamber assembly 1 comprises two essentially semi-cylindrical casings 4 facing each other on their flat sides. The enclosure 3 is an essentially cylindrical tube that surrounds the two casings 4. This design is particularly compact and advantageous in terms of heating, especially when the casings 4 are made of a sensitive material and the heating system is an induction system 13.

[0066] According to one embodiment, the deposition unit 5 also comprises engagement means 14 adapted to couple with an end effector of an automatic processing machine to enable the deposition unit 5 to be automatically and integrally extracted / inserted from / into its casing 4.

[0067] It should be noted that the engagement means 14 may be a groove or protrusion adapted to mechanically couple with an end effector, for example, an end effector having a "Y-like" shape, as shown in Figures 4 and 5.

[0068] Advantageously, this embodiment makes it possible to implement automated solutions for accessing the deposition unit for preventive maintenance operations, thereby simplifying and automating these operations.

[0069] According to a second aspect, the invention relates to a reactor 2 for the epitaxial deposition of semiconductor films on at least two substrates.

[0070] The reactor 2 comprises (a) at least one reaction chamber assembly 1 according to any one of the above embodiments, (b) a heating system adapted to heat the at least two substrates, and (c) gas lines adapted to flow gases in and out of each deposition unit 5.

[0071] Advantageously, the reactor according to the present invention is characterized by a compact batch design and can provide a "single wafer"-like deposition environment, thus positively impacting the quality of the processed substrate.

[0072] For example, the reactor may advantageously comprise two or three reaction chamber assemblies for processing at least four or six substrates at a time.

[0073] According to one embodiment, the heating system of the reactor 2 is an induction system 13 .

[0074] For example, in a non-limiting embodiment, the induction system 13 comprises one or more solenoids wrapped around the reaction chamber assembly 1, preferably around the enclosure 3 of the reaction chamber assembly 1, as shown in FIG.

[0075] According to one embodiment, the heating system is configured to heat at least two substrates to the same and / or different temperatures relative to each other, meaning that the heating system is configured to heat the receiving areas of two deposition units arranged in different casings to different temperatures.

[0076] For example, the heating system can be connected to a displacement mechanism such that the heating system can be displaced relative to the reaction chamber assembly such that one deposition unit is subjected to different heating conditions than another deposition unit.

[0077] In the case of the induction system described above and shown in Figure 2, the heating system can be displaced along the z-direction relative to the enclosure. To maximize this effect, the heating system can be asymmetric, such as an elliptical shape as shown in Figure 3. Alternatively, the heating system can be significantly larger than the enclosure to allow sufficient displacement and to adapt the heating conditions to each deposition unit.

[0078] Advantageously, the magnetic flux coupled to the substrate holder can be adjusted to compensate for differences in the temperature of the casing, which makes it possible to have independently controlled deposition units.

[0079] To this effect, the guidance system 13 can advantageously be connected to a servo control: the average temperature can be used to control the total power, while the actual temperature difference within the deposition unit controls the position of the coil.

[0080] According to one embodiment, the heating system comprises at least two independent heating elements, for example, two separate induction structures, curved or flat, may be used.

[0081] In this way, each heating element can independently control the temperature of the deposition unit. In this case, the two induction elements can be fixed in space but independently powered.

[0082] The present invention can be implemented independently in a horizontal or vertical reactor.

[0083] According to one embodiment, reactor 2 is a horizontal cross-flow reactor for the deposition of silicon carbide.

[0084] An example of the above embodiment is provided in FIG.

[0085] It is understood that reactor 2 according to any one of the above embodiments may comprise many additional elements other than those explicitly listed herein, which one of ordinary skill in the art may recognize as desirable or implicit in the definition.

[0086] For example, reactor 2 may include one or more pumps, one or more vacuum systems, one or more outer cabinets, one or more ports, one or more monitoring systems, one or more automation systems, and / or one or more security systems.

[0087] The subject matter of the present disclosure includes all novel and non-obvious combinations and sub-combinations of the various processes, systems, and configurations, as well as other features, functions, operations and / or properties disclosed herein, and any and all equivalents thereof. [Explanation of symbols]

[0088] 1. Reaction Chamber Assembly 2. Reactor 3 Enclosure 4 Casing 5 Sedimentary Unit 6 Receptive Area 7 Substrate holder 8 Entrance 9 exit 10 Connection means 11 Intermediate insulating element 12 Insulation cover 13 Guidance System 14 Engagement means 15 Transitional Parts 16 Removable Lid 17 Gas Liner

Claims

1. A reaction chamber assembly (1) of a reactor (2) for epitaxial deposition of semiconductor films onto at least two substrates, comprising: an enclosure (3), - at least two casings (4) housed within said enclosure (3); at least two stacking units (5), an insulation system, Each casing (4) houses at least one deposition unit (5); Each deposition unit (5) is provided with at least one receiving area (6) adapted to receive a substrate holder (7) and suitable for epitaxial deposition of a semiconductor film on said substrate; A reaction chamber assembly (1), wherein the insulation system comprises an intermediate insulation element (11) positioned between the at least two casings (4).

2. 2. The reaction chamber assembly (1) according to claim 1, wherein each deposition unit (5) is provided with one receiving area (6) adapted to receive a substrate holder (7) for a single substrate.

3. 3. The reaction chamber assembly (1) of claim 1 or 2, wherein the deposition unit (5) comprises a container, optionally comprising a removable lid (16) releasably connected to the container.

4. The reaction chamber assembly (1) according to any one of claims 1 to 3, wherein each deposition unit (5) is mechanically connected to the casing (4) via a releasable coupling means (10) and is movable integrally with the casing (4).

5. The reaction chamber assembly (1) according to any one of claims 1 to 4, wherein said releasable coupling means (10) is a non-permanent mechanical interlocking mechanism, a support mechanism and / or a fastening mechanism.

6. The deposition unit (5) an inlet (8) suitable for introducing a gas flow into said deposition unit (5); A reaction chamber assembly (1) according to any one of claims 1 to 5, comprising: an outlet (9) suitable for discharging said gas flow outside said deposition unit (5).

7. The reaction chamber assembly (1) according to any one of claims 1 to 6, wherein the insulation system comprises at least one insulating cover (12) adapted to fully or partially cover at least one of the casings (4).

8. The reaction chamber assembly (1) according to any one of claims 1 to 7, wherein the casing (4) is essentially hollow and extends along a longitudinal direction (x).

9. 9. The reaction chamber assembly (1) of claim 8, wherein the casing (4) has an essentially hollow prismatic, cylindrical, or semi-cylindrical shape with a polygonal, circular, semi-circular, oval, or elliptical cross section in a transverse plane (yz) perpendicular to the longitudinal direction (x).

10. The reaction chamber assembly (1) according to any one of claims 1 to 9, wherein the enclosure (3) is made of quartz.

11. A reaction chamber assembly (1) according to any one of claims 1 to 10, wherein each casing (4) is made of a sensitive material suitable for being heated via an induction system (13).

12. The reaction chamber assembly (1) according to any one of claims 1 to 11, further comprising an engagement means (14) adapted to couple with an end effector of an automatic processing machine so that the deposition unit (5) is automatically and integrally pulled out / inserted into the casing (4).

13. A reactor (2) for epitaxial deposition of semiconductor films onto at least two substrates, comprising: - at least one reaction chamber assembly (1) according to any one of claims 1 to 12, a heating system adapted to heat said at least two substrates; a reactor (2) comprising gas lines adapted to flow gases into and out of each deposition unit (5).

14. 14. The reactor (2) according to claim 13, wherein the heating system is an induction system (13).

15. 15. The reactor (2) according to claim 13 or 14, wherein the heating system is configured to heat the at least two substrates to the same temperature and / or to different temperatures relative to each other.

16. 16. The reactor (2) according to claim 15, wherein the heating system is displaceable with respect to at least two of the deposition units (5) and / or comprises at least two independent heating elements.

17. The reactor (2) according to any one of claims 13 to 16, wherein the reactor (2) is a cross-flow reactor for the deposition of silicon carbide.

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