CN117926210A

CN117926210A - MOCVD equipment for preheating reaction gas

Info

Publication number: CN117926210A
Application number: CN202410269457.6A
Authority: CN
Inventors: 徐国强; 张丽娜; 闻洁
Original assignee: Hangzhou Longsheng Extension Technology Co ltd
Current assignee: Hangzhou Longsheng Extension Technology Co ltd
Priority date: 2024-03-10
Filing date: 2024-03-10
Publication date: 2024-04-26

Abstract

The invention provides MOCVD equipment preheated by reaction gas, which comprises the following components: a reaction chamber housing for providing an environment in which the reaction gases chemically react; an air inlet and an air outlet for supplying and exhausting a reaction gas into and from the reaction chamber housing, respectively; and an inner cylinder (41) disposed within the reaction chamber housing, and a reaction gas channel (51) is formed between the inner cylinder (41) and the reaction chamber housing, wherein the MOCVD apparatus is configured such that the inner cylinder (41) and the reaction chamber housing can relatively rotate; and wherein the MOCVD apparatus is configured such that the reactant gases are preheated prior to entering the reaction chamber housing through the gas inlet. The reaction gas preheated MOCVD equipment can reduce the huge energy consumption of the MOCVD equipment, reduce the running cost of the equipment, improve the temperature uniformity, the gas flow uniformity and/or the gas concentration uniformity, improve the deposition quality of semiconductor devices and increase the productivity.

Description

MOCVD equipment for preheating reaction gas

Technical Field

The invention relates to the technical field of semiconductors, in particular to a semiconductor epitaxial thin film vapor deposition technology, and specifically relates to novel reaction gas preheated MOCVD (metal organic chemical vapor deposition) equipment.

Background

MOCVD (metal organic chemical vapor deposition) is a key device for manufacturing semiconductor epitaxial wafers, the performance and the productivity of the epitaxial wafers are one of key determinants of the performance and the yield of semiconductor chips, and the preparation of epitaxial films by adopting MOCVD technology has the advantages of being capable of accurately controlling the components and the flow of reactants, accurately controlling the thickness of films, easily preparing uniform films with larger areas and being suitable for industrial production.

The MOCVD reaction chamber commonly used in the market at present mainly comprises a planetary reaction chamber, a vertical near-coupling spraying reaction chamber, a vertical high-speed rotating disk reaction chamber and the like. These types of MOCVD reaction chambers are characterized in that the substrates to be deposited are all horizontally placed on a horizontal disk, and the reaction gases enter the reaction chamber to deposit the resulting products on the horizontally placed substrates. Taking a German AIXTRON planetary reaction chamber as an example, a rotatable graphite base is arranged in the reaction chamber, the graphite base is disc-shaped, a plurality of substrates form a group, the plurality of substrate groups are circumferentially and uniformly arranged on the graphite base, the graphite base can revolve, meanwhile, each substrate group rotates, III-group and V-group reactants enter from the center of an upper cover, flow horizontally along the annular space between the graphite base and a ceiling in a radial manner through a grid, and the uniform growth speed of each substrate surface is obtained by utilizing rotation and revolution.

As the deposition of the semiconductor film has higher requirements on the temperature field, the speed field and the concentration field of the reaction gas, the requirement on multi-field uniformity is continuously improved along with the improvement on the performance requirement of the semiconductor chip. Meanwhile, the demand of the semiconductor industry for a large-area, high-productivity and high-quality thin film deposition apparatus is urgent. The limitation of the existing reaction chamber structure is that it is difficult to increase the productivity because the size of the reaction chamber needs to be increased to increase the productivity, and the uniformity of the temperature field, the velocity field and the concentration field is reduced with the increase of the size of the reaction chamber, so that it is very difficult to achieve higher productivity.

In addition, when the MOCVD equipment in the prior art is used, after the gas enters the internal channel, the gas needs to be heated through the wall surface of the high-temperature graphite base, so that the temperature of the gas is very high at the outlet position, and the gas is directly discharged to the environment, so that great energy waste is generated.

Disclosure of Invention

The invention aims to at least partially overcome the defects of the prior art and provide a novel MOCVD equipment. The object of the present invention may be plural, but it is not intended to solve all problems, and achieve all objects, and the object of the present invention is achieved by solving one of the technical problems.

The invention also aims to provide the MOCVD equipment preheated by the reaction gas, so that the huge energy consumption of the MOCVD equipment is reduced, and the running cost of the equipment is reduced.

It is also an object of the present invention to provide a reactive gas pre-heated MOCVD tool having improved temperature uniformity, gas flow uniformity and/or gas concentration uniformity.

The invention also aims to provide MOCVD equipment preheated by the reaction gas, which can improve the deposition quality of the semiconductor device.

The invention also aims to provide the MOCVD equipment preheated by the reaction gas, which can increase the productivity, or can easily increase the productivity while obtaining high-quality and high-performance deposition products.

In order to achieve one of the above objects or purposes, the technical solution of the present invention is as follows:

a reactive gas pre-heated MOCVD tool, said MOCVD tool comprising:

a reaction chamber housing for providing an environment in which the reaction gases chemically react;

An air inlet and an air outlet for supplying and exhausting a reaction gas into and from the reaction chamber housing, respectively; and

An inner cylinder arranged in the reaction chamber shell, and a reaction gas channel is formed between the inner cylinder and the reaction chamber shell,

Wherein the MOCVD equipment is configured to enable relative rotation between the inner cylinder and the reaction cavity shell; and

Wherein the MOCVD apparatus is configured such that the reaction gas is preheated before entering the reaction chamber housing through the gas inlet.

According to a preferred embodiment of the present invention, the inner cylinder is configured to be rotatable about a longitudinal axis of the inner cylinder, and the reaction chamber shell is configured to remain stationary during operation of the MOCVD tool; or alternatively

At least a portion of the reaction chamber housing is configured to be rotatable about a longitudinal axis of the reaction chamber housing, and the inner barrel is configured to remain stationary during operation of the MOCVD tool; or alternatively

At least a portion of the reaction chamber housing and the inner tube are configured to be rotatable simultaneously, but the rotational direction or rotational speed of the inner tube and the reaction chamber housing is different.

According to a preferred embodiment of the present invention, the MOCVD equipment further comprises a heat exchanger provided on the gas supply line communicating with the gas inlet and the gas exhaust line communicating with the gas outlet.

According to a preferred embodiment of the present invention, the gas supply pipe is provided with a flow valve for controlling the flow rate of the reaction gas supplied into the reaction chamber housing; and/or

And a pressure control valve is arranged on the exhaust pipeline.

According to a preferred embodiment of the invention, a filter and/or a gas reservoir is provided on the exhaust gas conduit upstream of the heat exchanger.

According to a preferred embodiment of the present invention, a filter, an air tank and a pressure control valve are provided in this order in the exhaust direction on the exhaust pipe.

According to a preferred embodiment of the invention, downstream of the heat exchanger, the exhaust gas conduit is connected to an exhaust gas treatment unit.

According to a preferred embodiment of the present invention, the gas inlet is provided with a gas inlet element configured to guide the reaction gas into the reaction gas channel and along the reaction gas channel to the gas outlet.

According to a preferred embodiment of the present invention, the gas outlet of the gas inlet element is a longitudinal gas outlet, and the gas outlet is located in the reaction gas channel and extends along the longitudinal axis direction of the inner cylinder; or alternatively

The number of the air inlet elements is multiple, the air outlets of the air inlet elements are positioned in the reaction gas channel, and the air inlet elements are uniformly distributed along the longitudinal axis direction of the inner cylinder.

According to a preferred embodiment of the present invention, the reaction chamber housing is provided with an air inlet element, an air outlet element and a partition element; the air inlet element and the air outlet element penetrate through the cavity wall of the reaction cavity shell and extend into the reaction gas channel; the partition member is located in the reaction gas channel between the gas inlet member and the gas outlet member.

Compared with the prior art, the invention has the following beneficial effects: according to the MOCVD equipment preheated by the reaction gas, the regenerator/heat exchanger and the like are additionally arranged in the system, so that the gas in the reaction chamber shell is discharged through the exhaust port, solid particles are filtered out and then enter the heat exchanger through the pressure control valve to serve as hot side gas, cold side gas (the reaction gas to be entered into the reaction gas channel) is heated, and the heat of the high Wen Duoyu at about thousands of degrees is transferred to the cold side gas, so that the cold side gas in a normal temperature state can be preheated to a higher temperature meeting the process requirement, the heating power of a heating element is greatly reduced, the huge energy consumption of the MOCVD equipment is greatly reduced, the operation cost of the equipment is reduced, and the equipment has great advantages in improving the operation cost and the temperature uniformity of the MOCVD equipment.

Further, according to the reactive gas preheating MOCVD apparatus of the present invention, the inner cylinder is provided in the reaction chamber housing, the reactive gas passage is formed between the inner cylinder and the reaction chamber housing, the reactive gas passage having a constant cross section is easily obtained based on the shapes of the inner cylinder and the inner wall surface of the reaction chamber housing, and therefore, the reactive gas supplied into the reactive gas passage through the gas inlet can maintain a uniform velocity field and concentration field, and the layout of the heating element in the circumferential direction in the inner cylinder or the cavity wall of the reaction chamber housing is also easily obtained with a uniform temperature field, and therefore, the reactive gas preheating MOCVD apparatus of the present invention has improved temperature uniformity, gas flow uniformity and/or gas concentration uniformity, and thus can improve the deposition quality of the semiconductor device. More importantly, the inner cylinder and the reaction cavity shell are coaxially arranged, the increase of the productivity can be easily realized by increasing the axial and radial dimensions of the equipment (the area capable of bearing the substrate is increased), and the increase of the size of the equipment has no influence on the uniformity of the speed field, the concentration field and the temperature field of the gas in the reaction cavity shell, so that the problem that the mass production of epitaxial equipment in the semiconductor industry is limited at present can be well solved. Therefore, the reactive gas preheated MOCVD apparatus of the present invention can increase productivity and can simultaneously ensure high quality and high performance of deposition products.

Drawings

FIG. 1 is a schematic cross-sectional view of a planetary reaction chamber of the prior art;

FIG. 2 is a top view of a graphite susceptor of the planetary reaction chamber of FIG. 1;

FIG. 3 is a schematic cross-sectional view of an MOCVD apparatus according to one embodiment of the present invention;

FIG. 4 is a cross-sectional view of MOCVD apparatus according to FIG. 3;

fig. 5 shows an MOCVD tool according to another embodiment of the present invention, corresponding to fig. 4;

FIG. 6 is a schematic cross-sectional view of an MOCVD apparatus according to an embodiment of the present invention, wherein the substrate is mounted on the outer circumference of the inner cylinder;

FIG. 7 is a C-C cross-sectional view of the MOCVD apparatus of FIG. 6;

FIG. 8 is a schematic cross-sectional view of an MOCVD apparatus according to an embodiment of the present invention, wherein the substrate is mounted on the outer circumference of the inner cylinder and the inner side of the reaction chamber housing at the same time;

FIG. 9 is a D-D sectional view of the MOCVD apparatus of FIG. 8;

Fig. 10 shows a MOCVD tool according to another embodiment of the present invention, corresponding to fig. 9, but with a different arrangement of the second heating element;

FIG. 11 is a schematic cross-sectional view of an MOCVD apparatus according to an embodiment of the present invention, wherein the substrate is mounted on the inner side of the reaction chamber housing;

FIG. 12 is an E-E cross-sectional view of the MOCVD apparatus of FIG. 11;

FIG. 13 shows one arrangement of mounting locations on the outer cartridge for mounting substrates;

FIG. 14 is a schematic cross-sectional view of an MOCVD apparatus according to an embodiment of the present invention;

fig. 15 is an enlarged view of region K in fig. 14;

FIG. 16 is a schematic cross-sectional view of an MOCVD apparatus according to an embodiment of the present invention;

FIG. 17 is a schematic cross-sectional view of an MOCVD apparatus according to an embodiment of the present invention;

FIG. 18 is a schematic cross-sectional view of an MOCVD apparatus according to an embodiment of the present invention;

FIG. 19 is a G-G cross-sectional view of the MOCVD apparatus of FIG. 18;

FIG. 20 is a schematic cross-sectional view of an MOCVD apparatus according to an embodiment of the present invention;

FIG. 21 is a H-H cross-sectional view of the MOCVD apparatus of FIG. 20;

FIG. 22 is a schematic cross-sectional view of a spindle of a MOCVD apparatus according to an embodiment of the present invention;

FIG. 23 is a schematic cross-sectional view of an MOCVD apparatus according to an embodiment of the present invention;

Fig. 24 is a schematic cross-sectional view of an MOCVD tool according to one embodiment of the present invention.

List of reference numerals:

11 actuation means; 12 transmission shafts; 13 an active rotation unit; 14 a driven rotation unit; a 15-axis rotation; a 16 bearing; 17 a support element; 31 a first housing; 32 a second housing; 41 inner cylinder; 42 a first insulating material; 43 a first heating element; 44 an outer cylinder; 45 a second insulating material; 46 heating element support rods; 47 an annular heating belt; 48 end insulation; 49 a central support ring; 50 fixing the assembly; 51 a reaction gas channel; 52 an air intake element; 53 exhaust element; 54 a separation element; 55 a central support shaft; 56 insulating sheets; 57 a support cylinder; 58 struts; a 59 flange; 60 rotating the seal; 64 fixing grooves; 66 double-layer water cooling pipes; 67 outside channels; 68 an inboard channel; 69 collector rings; 70 wires; 71 a first mounting location; a 72 substrate; 73 a second heating element; 74 heating element fixing portion; 75 a second mounting location; 101 a lifting assembly; 102 a first housing coupling member; 103a second housing coupling member; 121 air storage tanks; 122 a filter; 123 pressure control valve; 124 heat exchanger; 125 exhaust duct; 126 flow valve; 127 air supply line; 128 tail gas treatment unit.

Detailed Description

Exemplary embodiments of the present invention are described in detail below with reference to the attached drawing figures, wherein the same or similar reference numerals denote the same or similar elements. Furthermore, in the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the embodiments of the present disclosure. It may be evident, however, that one or more embodiments may be practiced without these specific details. In other instances, well-known structures and devices are shown in the drawings in order to simplify the drawings.

Fig. 3 and 4 show the basic structure of an MOCVD equipment according to an embodiment of the present invention, which is a rotary MOCVD equipment, which is called a rotary type because the inner cylinder and the reaction chamber housing of the MOCVD equipment can be relatively rotated, as will be described later. As shown in the figure, the MOCVD apparatus mainly comprises a reaction chamber shell, an air inlet and an air outlet, an inner cylinder 41, an actuating device 11 and a transmission mechanism. The reaction chamber housing is used for providing an environment for the reaction gas to chemically react, and typically, the environment is a high-temperature and low-pressure environment; the inner tube 41 is disposed in the reaction chamber housing, and a reaction gas channel 51 is formed between the inner tube 41 and the reaction chamber housing, as shown in fig. 3 to 4, the inner tube 41 is substantially cylindrical, and the inner wall surface of the reaction chamber housing is also substantially cylindrical, and the inner tube 41 and the reaction chamber housing are coaxially arranged, so that the reaction gas channel 51 is substantially annular. In addition to the above parts, the complete MOCVD apparatus also includes a gas delivery system, a base support, an exhaust gas treatment system, and the like.

The reaction chamber housing is hollow, so that the inner cylinder 41 can be placed in the reaction chamber housing, and the reaction chamber housing is mainly composed of a chamber wall, wherein the chamber wall comprises: a housing; an outer cylinder 44 provided in the housing and fixed with respect to the housing; and a second heat insulating material 45 provided between the housing and the outer cylinder 44. The outer case, which is the outermost layer of the reaction chamber case, includes a first case 31 and a second case 32, the first case 31 and the second case 32 being changeable between a first state of being coupled to each other to close the inner tube 41 and a second state of being separated from each other to expose the inner tube 41, the first case 31 and the second case 32 ensuring sealability of the reaction chamber case interior from the external environment. Since the outer shell is divided into two parts, the outer shell 44 and the second insulation material 45 between the outer shell and the outer shell 44 should also be composed of two parts, accordingly. Optionally, end covers are arranged at two ends of the outer cylinder to form a cavity, so that the air tightness inside the reaction cavity shell is ensured.

At least the portions of the inner cylinder 41 or the reaction chamber housing facing each other include a graphite material, or a tungsten material, or a molybdenum material, surface-coated with a SiC coating. For the inner cylinder 41 and the outer cylinder 44 to resist high temperature, they are usually graphite cylinders coated with SiC coating, or metal materials such as high temperature resistant tungsten, molybdenum and the like can be adopted, and the thickness of the coating can be determined according to the mechanical properties of the materials.

An inlet and an outlet are provided on the reaction chamber housing for supplying and discharging the reaction gas into and from the reaction chamber housing, respectively, in this embodiment an inlet element 52 is provided on the inlet and an outlet element 53 is provided on the outlet, said inlet element 52 and outlet element 53 extending from outside the reaction chamber housing through the chamber wall of the reaction chamber housing into the reaction gas channel 51, said inlet element 52 being configured to guide the reaction gas into the reaction gas channel 51 and along the reaction gas channel 51 to the outlet, as indicated by the arrow in fig. 4, the exhaust gas after reaction in the reaction gas channel 51 being discharged from the outlet element 53. In addition to the gas inlet element 52 and the gas outlet element 53, a partition element 54 is provided on the reaction chamber housing, and the partition element 54 is located in the reaction gas channel 51 between the gas inlet element 52 and the gas outlet element 53 for preventing the back flow of the exhaust gas to the gas inlet side.

As shown in fig. 4, the gas inlet element 52 and the gas outlet element 53 extend into the reaction gas channel 51 from outside the reaction chamber housing through the chamber wall of the reaction chamber housing in the radial direction of the inner cylinder 41, and the gas inlet element 52 and the gas outlet element 53 are disposed adjacently in the circumferential direction of the reaction chamber housing. The gas inlet element 52, the gas outlet element 53, and the partition element 54 between the gas inlet element 52 and the gas outlet element 53 adjacent in the circumferential direction of the reaction chamber housing form a set of venting elements, and in the embodiment of fig. 4, the MOCVD equipment includes only one set of venting elements (full-circle flow). In this group of aeration elements, the outlet of the inlet element 52 may be an elongated outlet, i.e. there is only one inlet element and one outlet located in the reaction gas channel 51 and extending in the direction of the longitudinal axis of the inner cylinder 41, preferably over the entire longitudinal length of the inner cylinder 41, in order to ensure the uniformity of the reaction gas in the reaction gas channel 51. Or alternatively, in the group of ventilation elements, the number of the gas inlet elements 52 may be plural, the gas outlets of the plurality of gas inlet elements 52 are located in the reaction gas passage 51, and the plurality of gas inlet elements 52 are uniformly distributed along the longitudinal axis direction of the inner cylinder 41 so as to ensure uniformity of the reaction gas in the reaction gas passage 51. The exhaust element 53 may have the same form and arrangement as the intake element 52.

The embodiment shown in fig. 4 may be derived from an arrangement of the vent elements, and as such, the inlet element 52, the outlet element 53, and the partition element 54 between the inlet element 52 and the outlet element 53 adjacent in the circumferential direction of the reaction chamber housing form one set of vent elements, and the MOCVD equipment includes a plurality of sets of vent elements, for example, two or three sets, which are uniformly distributed in the circumferential direction of the reaction chamber housing, and if three sets of vent elements are provided on the reaction chamber housing at an angular interval of 120 degrees in the case of three sets, the reaction gas introduced from the inlet element 52 of the first set of vent elements is discharged from the outlet element 53 of the second set of vent elements after flowing through an angle of 120 degrees in the reaction gas passage 51; the reaction gas introduced from the gas inlet element 52 of the second group of ventilation elements flows through an angle of 120 degrees in the reaction gas channel 51 and is discharged from the gas outlet element 53 of the third group of ventilation elements; the reaction gas introduced from the gas inlet element 52 of the third group of ventilation elements flows through an angle of 120 degrees in the reaction gas channel 51 and is discharged from the gas outlet element 53 of the first group of ventilation elements.

Fig. 5 shows an embodiment of another arrangement (half-turn flow) of the intake element 52 and the exhaust element 53, as shown, the intake element 52 comprising a first intake element and a second intake element (intake element 52 on the left and intake element 52 on the right in fig. 5) adjacent in the circumferential direction of the reaction chamber housing, and a partition element 54 being provided between the first intake element and the second intake element; the exhaust element 53 includes a first exhaust element and a second exhaust element (the left exhaust element 53 and the right exhaust element 53 in fig. 5) that are adjacent in the circumferential direction of the reaction chamber housing, and a partition element 54 is provided between the first exhaust element and the second exhaust element; the intake element 52 and the exhaust element 53 are disposed substantially opposite each other in the radial direction of the reaction chamber housing. In this way, the reactant gas introduced from the first gas inlet element flows through the reactant gas passage 51 at an angle of 180 degrees and is discharged from the first gas outlet element, and the reactant gas introduced from the second gas inlet element flows through the reactant gas passage 51 at an angle of 180 degrees in the opposite direction and is discharged from the second gas outlet element.

The position of the air inlet element 52 can be designed at different positions according to the working environment and specific working conditions, and can be arranged at a position of the lower part of the outer shell of the reaction cavity shell in actual use, so that natural convection in the channel can be restrained. The reaction gas enters the reaction gas channel through the gas inlet element, is heated in the channel and causes chemical reaction to carry out film deposition. Since the sectional area of the passage in the process of flowing the reaction gas remains unchanged, the uniformity of the flow of the gas is very good. Since the inner tube and the reaction chamber housing can rotate relatively, when the inner tube 41 rotates, a gap is provided between the partition member 54 and the inner tube 41, which is a minute gap, so as to prevent the inner tube from being affected by the rotation. The separating element 54 may be a thin wall baffle, and is fixed on the outer cylinder, and the separating element 54 is used for preventing air intake and exhaust from being mixed. In a preferred embodiment, the divider member 54 may be provided with air holes on both sides thereof, into which a carrier gas (nitrogen) is injected at a certain velocity to form a gas barrier. On one hand, the air hole at the air inlet side is used for blocking the flow of the air inlet flow to the direction of the air outlet flow, so that the waste of an organic metal source is avoided; on the other hand, the air hole at the exhaust side is used for blocking the flow of exhaust air flow to the direction of inlet air flow, so that the source gas is prevented from being polluted.

Advantageously, the channels at the outlet of the inlet element 52 are curved with respect to the axial direction of the inlet element 52, so that the flow direction of the reactive gases supplied from the outlet is substantially tangential to a circle centered on a point on the longitudinal axis of the inner cylinder 41, furthermore the inlet element 52 is an inlet element with multiple channels, which are present in the form of a sleeve. The multiple channels are three or more channels because the reactant gas has multiple gases, with each layer of the sleeve running a different gas.

Further, the portion of the gas inlet element 52 protruding into the reaction gas channel 51 includes a radial section and a bent section bent with respect to the radial section; the bending section is provided with a first air outlet and a second air outlet, the flowing direction of the reaction gas supplied from the first air outlet is approximately tangential to a circle taking a point on the longitudinal axis of the inner cylinder 41 as a center, and the flowing direction of the reaction gas supplied from the second air outlet is approximately directed to the longitudinal axis of the inner cylinder 41 to form an air curtain. The exhaust gas is prevented from leaking to the air intake portion by these nozzles (second air outlets) whose air intake side is vertically downward, and an air curtain is formed to block the exhaust gas from entering the air intake side from the gap of the partition member 54.

Advantageously, the MOCVD apparatus is configured to enable relative rotation between the inner barrel 41 and the reaction chamber housing. This relative rotation may be achieved in several ways: the inner cylinder 41 is configured to be rotatable about a longitudinal axis of the inner cylinder 41, and the reaction chamber housing is configured to remain stationary during operation of the MOCVD apparatus; or at least a portion of the reaction chamber housing (outer cylinder or entire reaction chamber housing) is configured to be rotatable about a longitudinal axis of the reaction chamber housing, and the inner cylinder 41 is configured to remain stationary during operation of the MOCVD tool; or at least a part of the reaction chamber housing (the outer cylinder or the entire reaction chamber housing) and the inner cylinder 41 are configured to be rotatable at the same time, but the rotation direction or rotation speed of the inner cylinder 41 and the reaction chamber housing is different. Taking the embodiment shown in FIG. 3 as an example, the inner cylinder 41 can be actively rotated while the reaction chamber housing remains stationary.

It should be noted that the relative rotation of the inner tube 41 and the reaction chamber shell is not essential, and both may be kept relatively stationary, for example, they may be kept absolutely stationary during the operation of the MOCVD equipment, which also achieves the effect of the present invention to some extent, as long as it is possible to ensure that the reaction gas passages 51 have substantially the same cross section in the traveling direction of the reaction gas. In the case where the reactant gas channels are of uniform cross section, the flow velocity of the reactant gas in the channels is maintained substantially unchanged, so that a uniform flow field in the flow direction can be obtained. But the relative rotation can make the concentration of carrier gas/reactant gas in contact with the wafer substrate more uniform.

To achieve the operating temperature of MOCVD, the MOCVD apparatus further comprises heating elements, which may be disposed inside the inner barrel 41 and/or within the chamber walls of the reaction chamber housing. In general, the heating element may comprise: a plurality of heating strips arranged in parallel, each parallel to the longitudinal axis of the inner barrel 41 and distributed circumferentially with respect to the longitudinal axis of the inner barrel 41, as shown in fig. 3-4; or a plurality of annular heating bands arranged in parallel, which are distributed axially with respect to the longitudinal axis of the inner drum 41, as shown in fig. 23; or a plurality of heating blocks, not shown, uniformly distributed on a selected circumferential surface about the longitudinal axis of the inner barrel 41; or a combination of any two of a plurality of heating strips, a plurality of endless heating strips, and a plurality of heating blocks, as shown in fig. 18-21. The heating element can be a silicon molybdenum rod, a tungsten wire or a molybdenum wire, the material can be silicon molybdenum, tungsten or molybdenum, and the shape can be a block, a belt, a strip or the like. The heating power can be uniform or nonuniform, the size of the heating element is designed according to the gas temperature in the reaction gas channel, the heating power can be adjusted, and the temperature difference of the substrate surface is ensured to be less than 1 ℃.

Since both the reaction chamber housing and the inner tube 41 are substantially cylindrical, the heating elements are substantially uniformly disposed inside the inner tube 41 and/or in the chamber wall of the reaction chamber housing, so that heat generated by the heating elements is transferred to the reaction gas channel 51 in the radial direction of the reaction chamber housing or the inner tube 41. The heating element is preferably a silicon molybdenum rod, tungsten wire or molybdenum wire.

The inner cylinder 41 and the inner wall of the reaction cavity shell are both provided with heat insulating materials, as shown in fig. 3-4, the center of the inner cylinder 41 is penetrated by the rotating shaft 15, the inner cylinder 41 and the rotating shaft 15 are relatively fixed so that the inner cylinder 41 and the rotating shaft 15 can rotate together, the heat insulating materials are arranged between the outer wall of the inner cylinder 41 and the rotating shaft 15, and the inner cylinder 41 connects and fixes the inner cylinder 41 with the first heating element 41, the first heat insulating material 42 and the rotating shaft 15 into a whole through the supporting element 17; the supporting element 17 should be made of a material with good rigidity and small thermal conductivity, such as zirconia, which is resistant to high temperature and does not decompose. The first heating element 41 and the first heat insulating material 42 are combined in a mechanical connection manner, and are fixedly connected with the high-temperature-resistant rotary inner cylinder through the supporting element 17, and meanwhile, the other side of the supporting element 17 is fixedly connected with the rigid rotary shaft 15 through mechanical connection. The bearing 16 is installed on the rotating shaft 15, the whole inner cylinder 41 is supported and fixed through the left bearing 16 and the right bearing 16, the rotating shaft 15 can be made of stainless steel or other materials, a cooling structure is arranged in the rotating shaft, and the rigid rotating shaft is efficiently cooled in a liquid cooling or air cooling mode.

Referring to the embodiment of fig. 3-7, it can be seen that the inner cylinder 41 is a hollow inner cylinder, and the heating element is disposed inside the inner cylinder 41; the heating element comprises a plurality of heating strips arranged in parallel, each parallel to the longitudinal axis of the inner barrel 41 and distributed circumferentially with respect to the longitudinal axis of the inner barrel 41; and both ends of each heating strip are fixed to both ends of the inner tube 41 along the longitudinal axis. In the embodiment of fig. 8-12, the heating element is also provided in the chamber wall of the reaction chamber housing, the heating element being a second heating element 73, the second heating element 73 also comprising a plurality of heating strips arranged in parallel, each of the plurality of heating strips being parallel to and circumferentially distributed with respect to the longitudinal axis of the reaction chamber housing, and each of the plurality of heating strips being secured in the chamber wall of the reaction chamber housing by a heating element securing portion 74.

The heating strips can be designed in a combined mode in series and parallel according to process requirements, and the design has the following advantages: firstly, the energy consumption can be reduced to the maximum extent, and a series-parallel scheme with the minimum energy consumption is selected according to each working condition; secondly, the uniformity of the temperature fields at different positions of the inner cylinder has different requirements, so that the electric heating power can be adjusted in a targeted manner through the design. The heating element is arranged in the inner cylinder of the bearing substrate to uniformly heat the inner cylinder, and meanwhile, the double heat-preservation heat-insulation structure design of the two sides of the inner cylinder and the outer cylinder is adopted, so that the heat of the heating element is hardly dissipated into the external environment, the energy loss of equipment is reduced to the minimum, compared with the traditional MOCVD equipment at present, the energy consumption is reduced by at least one order of magnitude, and the equipment operation cost and the substrate epitaxial deposition cost are greatly reduced from the operation angle.

The following describes a transmission mechanism, which may be a simple transmission shaft or a magnetic coupling, for driving the inner cylinder 41 in rotation, such that the actuation device 11 is in transmission connection with the inner cylinder 41 via the magnetic coupling, as shown in fig. 3, or such that the actuation device 11 is in transmission connection with the inner cylinder 41 via a transmission shaft 12, as shown in fig. 23, the transmission shaft 12 is connected with the rotation shaft 15, and a rotary seal 60 is provided at the portion of the transmission shaft 12 passing through the reaction chamber housing. The transmission mechanism may have other structures. The magnetic coupler comprises a driving rotation unit 13 arranged outside the reaction cavity shell and a driven rotation unit 14 arranged in the reaction cavity shell, wherein the driving rotation unit 13 drives the driven rotation unit 14 in a non-contact mode; the driving rotation unit 13 is connected to the actuator 11, and the driven rotation unit 14 is connected to the inner cylinder 41.

As shown in fig. 6 and 7, a first mounting position 71 for mounting the substrate 72 is provided on the outer circumference of the inner tube 41, as shown in fig. 11 and 12, a second mounting position 75 for mounting the substrate 72 is provided on the inner side of the reaction chamber housing (outer tube 44), specifically, the mounting position is provided on the surface of the outer tube 44 facing the inner tube 41, as shown in fig. 8 to 10, a first mounting position 71 for mounting the substrate 72 is provided on the outer circumference of the inner tube 41, and a second mounting position 75 for mounting the substrate 72 is provided on the inner side of the reaction chamber housing (outer tube 44).

The number of the mounting sites on the inner tube 41 or the reaction chamber shell is plural, and the plurality of the mounting sites are uniformly distributed, specifically, the plurality of the mounting sites may be arranged in a matrix as shown in fig. 13, or the plurality of the mounting sites may be formed in a plurality of rows, and the mounting sites of adjacent rows are arranged to be staggered from each other. Each mounting location may be a securing recess 64 as shown in fig. 13, which may act to secure the substrate in place during rotation of the inner barrel about the axis.

Taking the rotation of the inner cylinder as an example, in the working process, the inner cylinder is rotated at a constant speed, so that the temperature uniformity of the large-size cylinder wall can be ensured, and the deposition uniformity of the surface of the wafer substrate is realized. In practice, the rotational speed of the inner barrel can be adjusted as required, or the inner barrel can be selected to be stationary and not rotated. The annular reaction gas channel of the cylindrical reaction chamber has the constant cross section along the flowing direction, thereby ensuring the uniformity of a gas velocity field, and simultaneously, the inner cylinder for bearing the substrate adopts a rotary design, thereby ensuring the uniformity of the temperature of the inner cylinder and the surface of the substrate, the uniformity of reactants on the surface of the substrate, and solving the problem of uneven deposition on the surface of the substrate after the MOCVD equipment is enlarged. Meanwhile, the increase of the size of the reaction cavity shell along the axial direction hardly has obvious influence on the temperature field, the speed field and the reactant diffusion concentration field of the film deposition reaction gas of the MOCVD equipment, so that the productivity of the MOCVD epitaxial wafer can be greatly improved, simultaneously, the very high epitaxial deposition quality is ensured, and the restriction of the production capacity of the MOCVD equipment in the semiconductor industry is effectively broken through.

Preferably, the distribution density or power density of the heating element at a location near the air inlet or outlet is greater than the distribution density or power density at a location remote from the air inlet or outlet. Referring to fig. 9 and 10, the distribution density of the second heating element 73 is greater near the inlet and outlet (inlet element 52 and outlet element 53) than at other locations because, in some arrangements, the lower inlet air temperature results in a lower temperature of the substrate 72 on the outer barrel 44 near the inlet, and therefore, a special heating element needs to be provided or added near the inlet of the outer barrel 44 to increase the local temperature of the outer barrel and ensure temperature uniformity across the 360 ° circumference of the outer barrel. Because the annular reaction gas channel is very small, the overall difference of the temperature of the inner cylinder and the outer cylinder is not large, and other positions of the outer cylinder can be provided with the outer cylinder heating element according to the temperature requirement, or the outer cylinder heating element is not provided, or only the outer cylinder heating element is provided locally (as shown in figure 10), so that the inner cylinder and the outer cylinder are heated by the heating element in the inner cylinder, and only the heating element is provided locally near the air inlet of the outer cylinder for compensation, so that the temperature difference of the whole outer cylinder is within 1 ℃, and the temperature range required by the deposition of the high-quality thin film of the outer cylinder substrate is satisfied.

Even if the outer cylinder 44 is not provided with a substrate, the outer cylinder 44 can be heated, so as to compensate the cooling effect of the reaction gas with lower temperature on the inner cylinder, the heating power of the heating element of the outer cylinder can be uniformly heated or non-uniformly heated along the circumferential direction, and the non-uniform heating is generally realized at the lower temperature part of the reaction gas inlet, and larger compensating heating power or denser heating wire design is adopted; along the movement direction of the reaction gas in the gas channel, the gas temperature gradually rises, and the heating element of the outer cylinder gradually reduces the compensation heating power so as to ensure that the temperature of the surfaces of all the substrates is more uniform and create a more uniform temperature environment for the reaction chamber. The other function of the auxiliary heating element of the outer cylinder is to accelerate the system response speed of MOCVD in temperature switching, and the power and the switch of the auxiliary heating element are controlled in advance according to the surface temperature condition of the inner cylinder and the temperature switching requirement, so that the system is ensured to realize the heating or cooling process in a faster time.

The embodiment of fig. 14, 15 shows the structure of the chamber wall of the reaction chamber housing, which is composed of the outer case (first case 31 and second case 32), the outer case 44, and the second heat insulating material 45 provided therebetween, and in addition, the chamber wall of the reaction chamber housing includes a support tube 57 provided between the outer case and the outer case 44; the support tube 57 is provided with a flange 59, the support tube 57 is fixed on the outer shell through the flange 59, a plurality of struts 58 are arranged between the support tube 57 and the outer barrel 44, the struts 58 extend along the radial direction of the reaction chamber shell, and the plurality of struts 58 are uniformly distributed along the circumferential direction of the reaction chamber shell. The support tube 57 and the support rod 58 are provided so that the outer tube is not directly contacted with the outer shells (the first shell 31 and the second shell 32) of the reaction chamber shell when the outer tube is fixed, and the direct contact connection has a large heat conduction and transfer amount because the temperature of the outer tube is very high above 1200 ℃, so that the support tube 57 and the support rod 58 are used for fixing the outer tube and reducing the heat transfer amount.

In fig. 14, the first housing 31 is located on the vertically upper side of the second housing 32, the second housing 32 is kept fixed, and the first housing 31 is configured to be movable with respect to the second housing 32; the first housing 31 is provided with two first housing coupling elements 102, the second housing 32 is provided with two second housing coupling elements 103, and the first housing coupling elements 102 are configured to be coupled with the second housing coupling elements 103; the MOCVD tool further comprises two lifting assemblies 101, said lifting assemblies 101 being connected to the first housing coupling member 102 for lifting or lowering the first housing 31. The lifting assembly 101 may be a hydraulic lever, and the lifting assembly 101 drives the first housing 31 to be lifted upward during loading and unloading of the substrates, thereby opening the reaction chamber housing, leaving a space for loading/unloading the wafer substrates.

Fig. 16 shows an example of a MOCVD equipment for preheating a reaction gas, in which the structure of a reaction chamber housing is the same as that of fig. 14, with which the reaction gas is preheated before entering the reaction chamber housing through a gas inlet. The MOCVD apparatus comprises a heat exchanger 124, the heat exchanger 124 is arranged on a gas supply pipeline 127 communicated with a gas inlet and an exhaust pipeline 125 communicated with a gas outlet, a flow valve 126 is arranged on the gas supply pipeline 127 and used for controlling the flow of the reaction gas supplied into the reaction chamber shell, and a pressure control valve 123 is arranged on the exhaust pipeline 125. A filter 122, an air tank 121, and the pressure control valve 123 are provided in this order in the exhaust direction on the exhaust pipe 125 upstream of the heat exchanger 124, and the exhaust pipe 125 is connected to an exhaust gas treatment unit 128 downstream of the heat exchanger 124.

Working principle and use flow of MOCVD equipment preheated by reaction gas: when in use, reaction gas enters the heat exchanger 124 from the gas supply pipeline 127, after being heated in the heat exchanger 124, the reaction gas enters the gas inlet element 52 after the flow and the pressure are controlled by the flow valve 126, and starts to react in the vapor deposition reaction chamber shell, and after the gas in the vapor deposition reaction chamber shell is reacted and discharged by the gas discharge element 53, the reaction gas does not directly enter the tail gas treatment system 128, but firstly enters the filter 122 to filter out solid particles, then enters the gas storage tank 121, enters the heat exchanger 124 through the pressure control valve 123 to serve as hot side gas, the cold side gas entering from the gas supply pipeline 127 is heated, and the high Wen Duoyu heat of about thousands of degrees is transferred to the cold side gas, so that the cold side gas entering the heat exchanger 124 in a normal temperature state can be preheated to a higher temperature, thereby greatly reducing the heating power of the heating element in the later stage, greatly reducing the energy consumption of MOCVD equipment and the whole operation cost; the invention utilizes the heat energy of the gas exhausted from the vapor deposition reaction cavity shell to heat the normal-temperature reaction gas, preheats the reaction gas to 200 ℃, can reach higher temperature according to the process requirement, reduces the temperature difference between the gas and the inner cylinder, and has great benefit for improving the uniformity of the temperature of the inner cylinder.

Figures 17-21, 23 show several different forms, arrangements and support of the heating elements, which are several embodiments of the zoned arrangement of the heating elements, the interior of the inner barrel 41 or the interior of the chamber wall of the reaction chamber shell being divided into different zones, the heating elements being present in at least two zones in different forms, in different distribution densities or in different power densities. In particular, the distribution density or power density of the heating element at a location proximate to the air inlet or outlet may be greater than the distribution density or power density at a location distal from the air inlet or outlet, or the heating element may have a different distribution density or power density at a location proximate to the end of the inner barrel 41 along the longitudinal axis and a location proximate to the center of the longitudinal axis of the inner barrel 41. For example, the heating element is disposed inside the inner barrel 41, and the inner barrel 41 includes a first region near the center of the longitudinal axis of the inner barrel 41 and two second regions near the ends of the inner barrel 41 along the longitudinal axis, while the heating element has a different form and arrangement in the first and second regions.

In the embodiment of fig. 17-19, the rotational shafts 15 are disposed on both ends of the inner barrel 41 along the longitudinal axis, the rotational shafts 15 do not pass through the center of the inner barrel 41, and the inner barrel 41 and the rotational shafts 15 are relatively fixed so that the inner barrel 41 and the rotational shafts 15 can rotate together. The heating elements are fixedly arranged inside the inner drum 41, the heating elements comprising a first heating element 43 and an annular heating band 47, the first heating element 43 being in a first region, which is designed as a plurality of heating strips arranged in parallel, which are each parallel to the longitudinal axis of the inner drum 41 and distributed circumferentially with respect to the longitudinal axis of the inner drum 41, the annular heating band 47 being arranged in a second region, the axis of which is parallel to the longitudinal axis of the inner drum 41. The outside of the annular heating belt 47 is provided with end heat insulating materials 48, two are axially arranged, and the end heat insulating materials 48 are vertically arranged at two ends of the inner cylinder and closely attached to the end covers of the inner cylinder, and can be connected together through mechanical devices. The end insulation 48 may be comprised of one to several layers of insulation or radiant heat shields, each layer being optimally designed to achieve an optimal insulation thickness at the temperatures to which it is subjected. The annular heating belt 47 is positioned between the end insulating material 48 and the heating strip with a certain spacing therebetween, which can be determined from the results of the simulation calculation. Furthermore, in the figures, the heating strip is a single row, but it may also be arranged in multiple rows.

The plurality of heating strips and the annular heating belt may be fixed within the inner tube 41 in various ways to rotate with the inner tube 41, for example, the plurality of heating strips are fixed on the inner circumferential surface of the inner tube 41, or the annular heating belt is fixed on the inner circumferential surface of the inner tube 41 or on both ends of the inner tube 41 along the longitudinal axis or on the end heat insulating material 48. The design of the annular heating belt is also used for guaranteeing the temperature uniformity of the reaction chamber, so that the temperature fields at the two ends of the inner cylinder and the middle position have smaller phase difference, and the deposition of epitaxial wafers at the two ends is guaranteed to be of high quality.

In the embodiment of fig. 20-21, the heating elements are identical in form, combination and location to the previous embodiments, including a plurality of heating strips and endless heating belts, but in a different manner of support and securement. A center support shaft 55 penetrates through the center of the inner cylinder 41 and protrudes from both ends of the inner cylinder 41 along the longitudinal axis, the center support shaft 55 being configured to be fixed with respect to the reaction chamber housing such that the inner cylinder 41 can rotate with respect to the center support shaft 55, for example, the center support shaft 55 is directly fixed to the outer housing of the reaction chamber housing, the center support shaft 55 is supported at the center of the rotation shaft 15 by a bearing such that the rotation shaft 15 can rotate around the center support shaft 55; the plurality of heating strips and the annular heating belt are fixed by the central support shaft 55 so that the plurality of heating strips and the annular heating belt do not rotate with the inner cylinder 41 during the operation of the MOCVD equipment.

The central support shaft 55 is provided with a plurality of central support rings 49, each central support ring 49 is provided with a plurality of heating element support rods 46 extending along the radial direction of the central support ring 49, and the plurality of heating element support rods 46 are uniformly distributed along the circumferential direction of the central support ring 49; the plurality of heating strips and the annular heating band are each directly or indirectly secured to the end of the heating element support rod 46 remote from the central support ring 49. The end of the heating element support bar 46 remote from the central support ring 49 is provided with a fixing plate on which the heating strips or the endless heating belt are fastened by screws, the fixing plate and screws constituting a fixing assembly 50. An insulating sheet 56 is provided between the heating strip and the end of the heating element support rod 46 (the fixing assembly 50), and an insulating sheet 56 is provided between the annular heating belt and the end of the heating element support rod 46. The material of the center support ring 49 may be selected from stainless steel or other nickel-based metals.

In the embodiment of fig. 23, unlike the embodiment shown in fig. 18, the heating elements in the inner cylinder 41 are all composed of annular heating belts, a certain distance is left between two adjacent annular heating belts, and the size and heating power of the annular heating belts can be adjusted according to the process requirements. The arrangement of the annular heating belt can be divided into a middle area and an edge area according to the temperature uniformity of the inner cylinder, different powers can be loaded in the areas due to different heat dissipation losses between the edges and the middle, the surface temperature of the inner cylinder is ensured to be more uniform through the areas with different axial directions, and the surface temperature difference between the two ends and the middle substrate is less than 1 ℃.

Furthermore, the heating strips can be designed in a partitioned manner along the circumferential direction, and the design can enable the electric heating power of different partitions to be independently adjusted. If the temperature of the air inlet is lower, the temperature field of the area is greatly different from the temperature field of the middle position of the reaction chamber, and the electric heating power of the partition heating strip can be independently regulated and increased at the moment so as to ensure the uniformity of the temperature field of the whole reaction chamber.

In addition, in the case where the center of the inner tube 41 is penetrated by the rotation shaft 15 and the inner tube 41 is relatively fixed to the rotation shaft 15 so that the inner tube 41 and the rotation shaft 15 can rotate together, a plurality of heating strips and/or an endless heating belt may be directly fixed to the rotation shaft 15.

As shown in fig. 22, a water cooling passage is provided in the rotary shaft 15, the water cooling passage is a double-layer water cooling passage, and includes an outer passage 67 and an inner passage 68 which are communicated, the outer passage 67 coaxially surrounds the outer periphery of the inner passage 68, the outer passage 67 is used for water supply, and the inner passage 68 is used for water drainage. The rotating shaft 15 is a hollow rotating shaft, the double-layer water cooling channel exists in the form of a double-layer water cooling pipe 66, and the double-layer water cooling pipe 66 is arranged in the hollow part of the rotating shaft 15.

As shown in fig. 24, the heating element of the MOCVD equipment is in an electric heating mode, the heating element is connected with an external power supply, and when the inner cylinder 41 rotates, the power supply of the first heating element 43 fixedly arranged on the inner cylinder 41 is realized in the following mode: a collecting ring 69 is arranged at the end part of the rotating shaft 15, the collecting ring 69 is connected with an external power supply through a wire 70, and the first heating element 43 is connected with the collecting ring 69 through a wire penetrating through the center of the rotating shaft 15, so that dynamic and static conversion is realized.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention. The scope of applicability of the present invention is defined by the appended claims and equivalents thereof.

Claims

1. A reactive gas pre-heated MOCVD tool, said MOCVD tool comprising:

An inner tube (41) disposed in the reaction chamber housing, and a reaction gas passage (51) is formed between the inner tube (41) and the reaction chamber housing,

Wherein the MOCVD apparatus is configured such that relative rotation is possible between the inner cylinder (41) and the reaction chamber housing; and

2. The reactive gas pre-heated MOCVD tool according to claim 1, wherein:

The inner barrel (41) is configured to be rotatable about a longitudinal axis of the inner barrel (41), and the reaction chamber housing is configured to remain stationary during operation of the MOCVD tool; or alternatively

At least a portion of the reaction chamber housing is configured to be rotatable about a longitudinal axis of the reaction chamber housing, and the inner barrel (41) is configured to remain stationary during operation of the MOCVD tool; or alternatively

At least a part of the reaction chamber housing and the inner tube (41) are configured to be rotatable at the same time, but the rotation direction or rotation speed of the inner tube (41) and the reaction chamber housing is different.

3. The reactive gas pre-heated MOCVD tool according to claim 1, wherein:

The MOCVD apparatus further comprises a heat exchanger (124), and the heat exchanger (124) is arranged on a gas supply pipeline (127) communicated with the gas inlet and a gas exhaust pipeline (125) communicated with the gas outlet.

4. A reactive gas pre-heated MOCVD tool according to claim 3, wherein:

The gas supply pipeline (127) is provided with a flow valve (126) for controlling the flow rate of the reaction gas supplied into the reaction cavity shell; and/or

The exhaust pipe (125) is provided with a pressure control valve (123).

5. A reactive gas pre-heated MOCVD tool according to claim 3, wherein:

A filter (122) and/or a gas storage tank (121) are/is arranged on the exhaust pipeline (125) and upstream of the heat exchanger (124).

6. A reactive gas pre-heated MOCVD tool according to claim 3, wherein:

a filter (122), an air tank (121), and a pressure control valve (123) are provided in this order along the exhaust direction in the exhaust pipe (125).

7. A reactive gas pre-heated MOCVD tool according to claim 3, wherein:

Downstream of the heat exchanger (124), the exhaust line (125) is connected to an exhaust gas treatment unit (128).

8. The reactive gas preheated MOCVD tool according to any of claims 1 to 7, wherein:

The gas inlet is provided with a gas inlet element (52), and the gas inlet element (52) is configured to guide the reaction gas into the reaction gas channel (51) and flow along the reaction gas channel (51) to the gas outlet.

9. The reactive gas pre-heated MOCVD tool according to claim 8, wherein:

The gas outlet of the gas inlet element (52) is a longitudinal gas outlet, and the gas outlet is positioned in the reaction gas channel (51) and extends along the longitudinal axis direction of the inner cylinder (41); or alternatively

The number of the air inlet elements (52) is multiple, the air outlets of the air inlet elements (52) are positioned in the reaction gas channel (51), and the air inlet elements (52) are uniformly distributed along the longitudinal axis direction of the inner cylinder (41).

10. The reactive gas pre-heated MOCVD tool according to claims 1 to 7, wherein:

An air inlet element (52), an air outlet element (53) and a separation element (54) are arranged on the reaction cavity shell; the air inlet element (52) and the air outlet element (53) penetrate through the cavity wall of the reaction cavity shell and extend into the reaction gas channel (51); the partition member (54) is located in the reaction gas channel (51) between the gas inlet member (52) and the gas outlet member (53).