CN115712000A - Speed measuring equipment for tray base - Google Patents

Abstract

The invention discloses a speed measuring device for a tray base. The two ends of the epitaxial reaction chamber are respectively provided with an air inlet port, an air outlet port, an air flow channel communicated with the air inlet port and the air outlet port and used for flowing of reaction gas; the tray base is rotatably arranged in the epitaxial reaction chamber, the airflow channel flows through the tray base, a speed measuring impeller which synchronously rotates along with the tray base is arranged below the tray base, and the speed measuring impeller is positioned outside the airflow channel; the speed measuring device comprises a signal emitter and a signal receiver, wherein the signal emitter and the signal receiver are respectively arranged at two ends of the epitaxial reaction chamber. The speed measuring impeller of the speed measuring equipment for the tray base is arranged below the tray base and positioned outside the airflow channel, so that the influence of the speed measuring impeller on the airflow of reaction gas is avoided, the rotating speed of the tray base is measured, and the quality of epitaxially grown crystals is improved.

Description

Speed measuring equipment for tray base

Technical Field

The invention relates to the technical field of semiconductors, in particular to a speed measuring device for a tray base.

Background

Epitaxial growth refers to the growth of a single crystal layer having a certain required crystal orientation with respect to a substrate on a substrate or a base wafer, and is one of the important processes in the manufacture of semiconductor devices. Different types of silicon carbide power devices require epitaxial layers of different thicknesses and doping concentrations, and the quality of the epitaxially grown crystal directly affects the performance of the silicon carbide power device. A widely used method for preparing the silicon carbide epitaxial layer at present is a CVD (Chemical Vapor Deposition) technique, in which a carrier gas is used to smoothly and uniformly transport a reaction gas to an epitaxial growth reaction chamber, and a substrate is generally continuously rotated on a tray base placed in the epitaxial growth reaction chamber to ensure uniformity of temperature and uniformity of Chemical Deposition, and the rotation rate of the tray base is crucial to the quality of an epitaxially grown crystal.

The existing speed measurement technology for the tray base is characterized in that a speed measurement detection hole is formed in a quartz heat insulation layer with light-tight property and a graphite layer, the speed measurement processing is performed on the tray base through the speed measurement detection hole, but the heat insulation capacity of the quartz heat insulation layer and the heating capacity of the graphite layer can be influenced by the processing mode, and the crystal growth is influenced by the fact that the temperature distribution in an epitaxial reaction chamber is uneven easily.

In another existing tray base speed measurement technology (CN 113945728), a positioner for speed measurement is disposed on a tray base, and the positioner rotates along with the tray base to perform circular motion, and since the crystal grown by the epitaxial growth process needs to have a stable and uniform airflow passing through the substrate, the positioner in this technology causes unstable airflow when performing circular motion, so that a large number of defects are generated in the epitaxially grown crystal, and the quality of the epitaxially grown crystal is directly affected.

Therefore, how to measure the rotation speed of the tray base and reduce the influence on the quality of the epitaxially grown crystal becomes a technical problem to be solved urgently by those skilled in the art.

Disclosure of Invention

In view of this, the present invention provides a speed measuring apparatus for a tray base, so as to measure the rotation speed of the tray base and reduce the influence on the quality of the epitaxially grown crystal.

In order to achieve the purpose, the invention provides the following technical scheme:

a tray base speed measurement device, comprising:

the epitaxial reaction chamber is provided with a gas inlet port, a gas outlet port and a gas flow channel which is communicated with the gas inlet port and the gas outlet port and is used for flowing reaction gas, wherein the gas inlet port and the gas outlet port are respectively arranged at two ends of the epitaxial reaction chamber;

the epitaxial reaction chamber comprises a tray base, a speed measurement impeller and a reaction chamber, wherein the tray base is used for bearing a substrate and is rotatably arranged in the epitaxial reaction chamber, the airflow channel flows through the tray base, the speed measurement impeller which synchronously rotates along with the tray base is arranged below the tray base, and the speed measurement impeller is positioned outside the airflow channel;

the speed measuring device comprises a signal transmitter and a signal receiver, the signal transmitter and the signal receiver are respectively arranged at two ends of the epitaxial reaction chamber, and the signal receiver is used for receiving signals periodically shielded by the speed measuring impeller.

Preferably, in the above-mentioned tray base tachometer apparatus, the tachometer impeller comprises:

the central rotating shaft is arranged below the tray base and is coaxial with the rotating center of the tray base;

the blade tests the speed, the blade that tests the speed set up in on the central pivot, and be for following two of the axis central symmetry of central pivot.

Preferably, in the above tray base speed measuring device, a surface of the central rotating shaft is coated with a high temperature resistant coating; and/or the presence of a gas in the atmosphere,

the surface of the speed measuring blade is coated with a high-temperature resistant coating.

Preferably, in the above tray substrate speed measurement apparatus, the epitaxial reaction chamber includes an upper graphite layer and a lower graphite layer;

the utility model discloses an impeller speed measuring device, including upper portion graphite layer, lower part graphite layer, tray base, speed measuring impeller, upper portion graphite layer with form between the graphite layer of lower part the air current passageway, just the graphite layer of lower part faces one side on graphite layer of upper portion has the tray mounting surface that is used for installing the tray base, the graphite layer of lower part is formed with and is used for holding speed measuring impeller's lower part graphite cavity.

Preferably, in the above tray base speed measuring device, the upper graphite layer and the lower graphite layer are both in a trapezoidal cavity structure, the bottom with the larger length of the upper graphite layer is a first channel side wall, the bottom with the larger length of the lower graphite layer is a second channel side wall, and the first channel side wall and the second channel side wall are arranged in parallel and form the airflow channel therebetween.

Preferably, in the above tray base speed measuring device, the first channel side wall and the second channel side wall are connected by a sealing end plate, the sealing end plate includes a first sealing end plate and a second sealing end plate, the first sealing end plate is respectively connected with a first side of the first channel side wall and a first side of the second channel side wall in a sealing manner, and the first side of the first channel side wall and the first side of the second channel side wall are located on the same side of the rotation center of the tray base;

the second sealing end plate is respectively connected with the second side of the first channel side wall and the second side of the second channel side wall in a sealing manner, and the second side of the first channel side wall and the second side of the second channel side wall are positioned on the same side of the rotation center of the tray base;

the first sealing end plate and the second sealing end plate are arranged along the extending direction of the airflow channel.

Preferably, in the above tray substrate velocimetry apparatus, the epitaxial reaction chamber further comprises:

the heat preservation felts are arranged on the outer surfaces of the upper graphite layer and the lower graphite layer;

the upstream heat shield is arranged at one end of an air inlet port of the epitaxial reaction chamber and is connected with the heat preservation felt, and a heat shield air inlet communicated with the air inlet port and a first signal through hole for a signal sent by the signal transmitter to pass through are formed in the upstream heat shield;

the downstream heat shield is arranged at one end of the air outlet port of the epitaxial reaction chamber and connected with the heat preservation felt, and a heat shield air outlet communicated with the air outlet port and a second signal via hole for passing a signal sent by the signal transmitter are formed in the downstream heat shield. .

Preferably, in the above tray base speed measuring device, the thermal insulation blanket includes:

the upper heat-preservation felt is sleeved on the upper graphite layer, and the inner surface of the upper heat-preservation felt is a surface matched with the outer surface of the upper graphite layer;

and the lower heat-preservation felt is sleeved on the lower graphite layer, and the inner surface of the lower heat-preservation felt is matched with the outer surface of the lower graphite layer.

Preferably, in the tray base speed measuring device, the outer surfaces of the upper heat-insulating felt and the lower heat-insulating felt are both semi-cylindrical surfaces.

Preferably, in the above tray base speed measurement device, the speed measurement device further includes a speed counter for calculating the rotation speed of the tray base at the frequency of the signal periodically blocked by the speed measurement impeller.

The invention provides a speed measuring device for a tray base. Two ends of the epitaxial reaction chamber are respectively provided with an air inlet port, an air outlet port, an air flow channel communicated with the air inlet port and the air outlet port and used for flowing of reaction gas; the tray base is used for bearing the substrate and is rotationally arranged in the epitaxial reaction chamber, the airflow channel flows through the tray base and is used for providing a stable and uniform airflow environment required by epitaxial reaction on the substrate, the speed measuring impeller synchronously rotating along with the tray base is arranged below the tray base and is positioned outside the airflow channel, and the influence of the speed measuring impeller on the airflow of the reaction gas is avoided; the speed measuring device comprises a signal transmitter and a signal receiver, the signal transmitter and the signal receiver are respectively arranged at two ends of the epitaxial reaction chamber, and the signal receiver is used for receiving signals periodically shielded by the speed measuring impeller so as to realize measurement of the rotating speed of the tray base. Compared with the prior art that the speed measuring detection hole is formed in the epitaxial reaction chamber or the positioner is arranged on the tray base, the speed measuring impeller of the speed measuring equipment for the tray base is arranged below the tray base and outside the airflow channel, so that the rotating speed of the tray base is measured, the influence of the speed measuring impeller on the airflow of the reaction gas is avoided, and the quality of the epitaxial growth crystal is improved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a side view of a speed measuring device for a base of a tray according to an embodiment of the present invention;

fig. 2 is a cross-sectional view of a speed measuring device for a base of a tray according to an embodiment of the present invention;

FIG. 3 is a side view of an upper insulation blanket provided by an embodiment of the present invention;

FIG. 4 is a cross-sectional view of an upper insulation blanket provided in accordance with an embodiment of the present invention;

FIG. 5 is a side view of an upper graphite layer provided by an embodiment of the present invention;

FIG. 6 is a cross-sectional view of an upper graphite layer provided by an embodiment of the present invention;

FIG. 7 is a top view of an upper graphite layer provided by an embodiment of the present invention;

FIG. 8 is a side view of a lower graphite layer provided by an embodiment of the present invention;

FIG. 9 is a cross-sectional view of a lower graphite layer provided in accordance with an embodiment of the present invention;

FIG. 10 is a top view of a lower graphite layer provided by an embodiment of the present invention;

FIG. 11 is a side view of a lower insulation blanket provided in accordance with an embodiment of the present invention;

FIG. 12 is a cross-sectional view of a lower insulation blanket provided in accordance with an embodiment of the present invention;

FIG. 13 is a top view of a retaining member according to an embodiment of the present invention;

FIG. 14 is a cross-sectional view of a retaining member according to an embodiment of the present invention;

FIG. 15 is a front view of a central spindle provided in accordance with an embodiment of the present invention;

FIG. 16 is a cross-sectional view of a central spindle according to an embodiment of the present invention;

FIG. 17 is a top view of a tachometer blade provided in accordance with an embodiment of the present invention;

FIG. 18 is a front view of a tachometer blade provided in accordance with an embodiment of the present invention;

FIG. 19 is a side view of an upstream heat shield provided by an embodiment of the present invention;

FIG. 20 is a front view of an upstream heat shield provided by an embodiment of the present invention;

FIG. 21 is a schematic diagram of a signal transmitter according to an embodiment of the present invention;

FIG. 22 is a side view of a downstream heat shield provided by an embodiment of the present invention;

FIG. 23 is a front view of a downstream heat shield provided by an embodiment of the present invention;

FIG. 24 is a side view of a tray base provided by an embodiment of the present invention;

FIG. 25 is a cross-sectional view of a base of a tray provided in accordance with an embodiment of the present invention;

FIG. 26 is a schematic diagram of a signal receiver provided in an embodiment of the present invention;

FIG. 27 is a top view of a centering shaft provided in accordance with an embodiment of the present invention;

fig. 28 is a side view of a centering shaft provided in accordance with an embodiment of the present invention.

Wherein 10 is an upper heat preservation felt, 11 is an upper graphite layer, 12 is a first sealing end plate, 13 is a lower graphite layer, 14 is a lower heat preservation felt, 15 is a locking piece, 16 is a central rotating shaft, 17 is a speed measuring blade, 18 is a lower graphite cavity, 19 is a gas flow channel, 20 is a second sealed end plate, 21 is an upper graphite cavity, 22 is an upstream heat shield, 23 is a signal emitter, 24 is a downstream heat shield, 25 is a tray base, 26 is a signal receiver, and 27 is a centering shaft.

Detailed Description

The core of the invention is to disclose a speed measuring device for a tray base, so as to realize the measurement of the rotating speed of the tray base and reduce the influence on the quality of the epitaxial growth crystal.

Hereinafter, embodiments will be described with reference to the drawings. The embodiments described below are not intended to limit the scope of the present invention as set forth in the claims. The entire contents of the configurations shown in the following embodiments are not limited to those required as solutions of the inventions described in the claims.

With reference to fig. 1 and 2, the speed measuring apparatus of the tray base disclosed in the present invention includes an epitaxial reaction chamber, a tray base 25 and a speed measuring device.

The two ends of the epitaxial reaction chamber are respectively provided with an air inlet port and an air outlet port, and an air flow channel 19 which is communicated with the air inlet port and the air outlet port and used for flowing the reaction gas.

Tray base 25 is used for the bearing substrate, and rotates and set up in epitaxial reaction chamber, airflow channel 19 flows through tray base 25 for provide the required steady even airflow environment of epitaxial growth on the substrate, the below of tray base 25 is provided with the impeller that tests the speed along with tray base 25 synchronous rotation, and the impeller that tests the speed is located airflow channel 19's outside, has guaranteed the steady homogeneity of reaction gas air current, has avoided the disturbance of impeller that tests the speed to reaction gas air current. Meanwhile, compared with the prior art that a locator for speed measurement is arranged on the upper surface of the tray base 25, the speed measurement equipment for the tray base disclosed by the invention can avoid the damage of the speed measurement impeller to the substrate caused by misoperation when the substrate is placed on the tray base 25, and the production cost is reduced.

The tray base 25 can be driven to rotate by a rotation driving mechanism. Specifically, the output end of the rotation driving mechanism is connected to the tray base 25, and drives the tray base 25 to rotate by gas. The driving principle of the rotary driving mechanism is the same as that of the prior art, the focus of the present application is not to change the driving manner of the tray base 25, and the detailed structure of the rotary driving mechanism is not described herein.

The speed measuring device comprises a signal emitter 23 and a signal receiver 26, the signal emitter 23 and the signal receiver 26 are respectively arranged at two ends of the epitaxial reaction chamber, and in combination with the graph 21 and the graph 26, the signal receiver 26 is used for receiving signals which are emitted by the signal emitter 23 and are periodically shielded by the speed measuring impeller so as to measure the rotating speed of the tray base.

In particular, the signal emitter 23 may be a laser emitter for emitting a laser signal, and the signal receiver 26 may be a laser receiver for receiving a laser signal periodically blocked by the tachometer impeller.

Compared with the prior art that the speed measuring detection hole is formed in the epitaxial reaction chamber or the positioner is arranged on the tray base, the speed measuring impeller of the speed measuring equipment for the tray base provided by the invention is arranged below the tray base 25 and outside the airflow channel 19, so that the rotating speed of the tray base is measured, the influence of the speed measuring impeller on the airflow of the reaction gas is avoided, and the quality of the epitaxial growth crystal is improved.

In order to better enable the measurement of the rotational speed of the tray base 25, the tachometer impeller comprises a central shaft 16 and a tachometer blade 17.

With reference to fig. 17 and 18, the speed measuring blades 17 are two blades that are disposed on the central rotating shaft 16 and are centrosymmetric along the axis of the central rotating shaft 16, and the symmetric arrangement can balance the stress on the central rotating shaft 16. The position of the signal emitter 23 is adjusted so that the signal emitted therefrom passes through the center of the speed measuring blade 17 in the vertical direction, thereby improving the accuracy of the measurement.

In a specific embodiment of the present disclosure, when the tray base 25 rotates, the speed measurement blade 17 rotates synchronously, and each time the tray base 25 rotates a circle, the signal is blocked by the speed measurement blade 17 twice, and the speed of the tray base 25 rotating a circle is calculated according to the time when the speed measurement impeller blocks the signal. Therefore, the rotating speed of the tray base 25 can be accurately controlled without influencing the smoothness of the airflow in the airflow channel 19, and the epitaxial growth crystal with high quality can be obtained.

The central rotating shaft 16 is arranged below the tray base 25, so that the speed measuring blade 17 arranged on the central rotating shaft 16 is positioned outside the airflow channel 19, the disturbance to the airflow of the reaction gas is avoided, and the influence on the epitaxial reaction carried out on the substrate is prevented.

Specifically, with reference to fig. 24 and 25, a mounting matching hole is formed in a rotation center of one end of the tray base 25 away from the surface of the supporting substrate, and the mounting matching hole may be a blind hole, and with reference to fig. 15 and 16, one end of the central rotating shaft 16 is in threaded fit with the mounting matching hole, so that the central rotating shaft 16 rotates along with the tray base 25; the other end of the central rotating shaft 16 is fixed with a speed measuring blade 17, and the speed measuring blade 17 is locked with the central rotating shaft through a locking piece 15, and the locking piece 15 can be a nut in combination with fig. 13 and 14.

The central rotating shaft 16 is coaxial with the rotation center of the tray base 25, that is, the speed measuring blade 17 rotates with the tray base 25 by using the rotation center of the tray base 25 as the rotation center, so that the stress of the tray base 25 can be balanced.

It will be appreciated by those skilled in the art that the signal from the signal emitter 23 will pass through the area covered by the tachometer blade 17 as it rotates. When the speed measuring blade 17 rotates along with the tray base 25, the speed measuring blade 17 periodically shields the signal sent by the signal transmitter 23, and the signal receiver 26 receives the signal periodically shielded by the speed measuring blade 17. The rotation speed of the tray base 25 can be obtained by calculating the signal received by the signal receiver 26.

Because the epitaxial reaction needs to be carried out in a high-temperature environment, in order to protect the central rotating shaft 16 and the speed measuring impeller to a certain extent, the surface of the central rotating shaft 16 is coated with a high-temperature resistant coating, and the surface of the speed measuring impeller is coated with a high-temperature resistant coating. Specifically, the high temperature resistant coating may be a SIC (silicon carbide), TAC (triacetyl cellulose film), or the like coating.

To provide the environment required for epitaxial growth, the epitaxial reaction chamber includes an upper graphite layer 11 and a lower graphite layer 13.

As shown in fig. 2, a gas flow channel 19 is formed between the upper graphite layer 11 and the lower graphite layer 13, and a side of the lower graphite layer 13 facing the upper graphite layer 11 has a tray mounting surface for mounting a tray base 25, and the gas flow channel 19 flows through the tray base 25 provided on the tray mounting surface and provides a reaction gas atmosphere necessary for epitaxial growth of a substrate held by the tray base 25.

The tray mounting surface of the lower graphite layer 13 is provided with a through hole, a centering shaft 27 is sleeved in the through hole, the central rotating shaft 16 arranged below the tray base 25 passes through the through hole, and the centering shaft 27 is used for preventing the lower graphite layer 13 from being worn when the central rotating shaft 16 rotates in combination with fig. 27 and 28.

The lower graphite layer 13 is also formed with a lower graphite chamber 18 for accommodating a speed measuring impeller, which is located in the lower graphite chamber 18 to avoid damage to the smooth uniformity of the reactant gas flow in the gas flow channel 19.

As will be understood by those skilled in the art in conjunction with fig. 5 to 10, in order to provide the temperature environment required for epitaxial growth, both the upper graphite layer 11 and the lower graphite layer 13 have a trapezoidal cavity structure, the upper graphite layer 11 has an upper graphite cavity 21, and the lower graphite layer 13 has a lower graphite cavity 18. In the prior art, the outer surfaces of the graphite layer and the heat-insulating layer are cylindrical surfaces, so that the problem of inaccurate positioning exists between the graphite layer and the heat-insulating layer during installation.

The upper graphite layer 11 and the lower graphite layer 13 are symmetrically arranged, so that the temperature distribution in the gas flow channel 19 can be balanced, and a stable temperature condition required for epitaxial growth of the substrate arranged on the tray base 25 is provided. Meanwhile, since the reaction gas may generate a certain pressure on the sidewalls of the upper graphite layer 11 and the lower graphite layer 13 forming the gas flow channel 19 when flowing through the gas flow channel 19, a certain amount of argon gas may be introduced into the chambers of the upper graphite layer 11 and the lower graphite layer 13 in order to balance the gas pressure of the reaction gas.

Specifically, the bottom with the larger length of the upper graphite layer 11 is a first channel side wall, the bottom with the larger length of the lower graphite layer 13 is a second channel side wall, and the first channel side wall and the second channel side wall are arranged in parallel to form an air flow channel 19 therebetween.

The quality of the epitaxially grown crystal has a direct influence on the quality of the crystal due to whether the reaction gas uniformly passes through the substrate. In order to adjust and restrict the shape of the reaction gas flow, the first channel side wall and the second channel side wall are connected by a sealing end plate, so that the gas flow channel 19 is in a pipe shape having only an inlet port and an outlet port, and the reaction gas smoothly flows through the tray base 25 along the gas flow channel 19, thereby preventing the reaction gas from flowing into other parts of the epitaxial reaction chamber.

Specifically, the sealing end plate includes a first sealing end plate 12 and a second sealing end plate 20, the first sealing end plate 12 is hermetically connected to a first side of the first channel side wall and a first side of the second channel side wall, respectively, the first side of the first channel side wall and the first side of the second channel side wall are located on the same side of the rotation center of the tray base 25; the second sealing end plate 20 is respectively connected with the second side of the first channel side wall and the second side of the second channel side wall in a sealing way, and the second side of the first channel side wall and the second side of the second channel side wall are positioned on the same side of the rotation center of the tray base 25; meanwhile, the first and second seal end plates 12 and 20 are disposed along the extending direction of the gas flow channel 19 so that the reaction gas flowing through the gas flow channel 19 has a certain trajectory.

In order to keep the epitaxial reaction chamber warm, the epitaxial reaction chamber is also provided with a thermal insulation layer, specifically comprising a thermal insulation felt, an upstream thermal shield 22 and a downstream thermal shield 24.

The heat preservation felt is arranged on the outer surfaces of the upper graphite layer 11 and the lower graphite layer 13, and is used for preserving heat of the upper graphite layer 11 and the lower graphite layer 13.

The outer surfaces of the upper graphite layers 11 are specifically the bottom of the upper graphite layers 11 having a small length and the outer surfaces of the two sloping side walls, and the outer surfaces of the lower graphite layers 13 are specifically the bottom of the lower graphite layers 13 having a small length and the outer surfaces of the two sloping side walls.

The upstream heat shield 22 is disposed at one end of the air inlet of the epitaxial reaction chamber and connected to the heat-insulating felt, and with reference to fig. 19 and 20, the upstream heat shield 22 is provided with a heat shield air inlet communicated with the air inlet and a first signal via hole for passing a signal emitted by the signal emitter 23.

The downstream heat shield 24 is disposed at one end of the air outlet of the epitaxial reaction chamber and connected to the heat insulation felt, and with reference to fig. 22 and 23, the downstream heat shield 24 is provided with a heat shield air outlet communicated with the air outlet and a second signal via hole for passing a signal emitted by the signal emitter 23.

When the tray base 25 is speed-measured, a signal from the signal transmitter 23 passes through the first signal via hole and the second signal via hole to pass through the rotation coverage area of the speed measuring blade 17 located in the lower graphite chamber 18, and is received by the signal receiver 26. Specifically, the first signal via and the second signal via may be circular holes.

When speed measuring devices are installed at two ends of the epitaxial reaction chamber, the signal emitter 23 is opened from the first signal through hole, the receiving position of the signal is observed at the second signal through hole, the signal receiver 26 is placed, after the tray base 25 is driven to operate, the signal receiving frequency displayed on a software interface connected with the speed measuring device is checked, if the frequency is found not to change, the position of the signal receiver 26 is checked and adjusted, and the signal receiver 26 is fixed after the frequency is adjusted. In practical use, the size of the speed measuring blade 17 can be increased properly to ensure the accuracy of calibration and speed measurement.

Further, in connection with fig. 1, in order to better arrange the insulation blanket on the outer surfaces of the upper graphite layer 11 and the lower graphite layer 13, the insulation blanket comprises an upper insulation blanket 10 and a lower insulation blanket 14.

As shown in fig. 3 and 4, the upper insulation blanket 10 is sleeved on the upper graphite layer 11, and the inner surface of the upper insulation blanket is a surface matched with the outer surface of the upper graphite layer 11. As shown in fig. 11 and 12, the lower insulation blanket 14 is sleeved on the lower graphite layer 13, and the inner surface is a surface matched with the outer surface of the lower graphite layer 13.

Because the epitaxial reaction chamber needs to be placed into the epitaxial reaction equipment for reaction, in order to match the circular bell jar structure of the epitaxial reaction equipment, the outer surfaces of the upper heat preservation felt 10 and the lower heat preservation felt 14 are both semi-cylindrical surfaces.

When the upper heat preservation felt 10 and the lower heat preservation felt 14 are respectively sleeved on the outer surfaces of the upper graphite layer 11 and the lower graphite layer 13, the end surfaces of the upper heat preservation felt 10 and the lower heat preservation felt 14, which are positioned at the air inlet port of the air flow channel 19, are connected with the upstream heat insulation cover 22, and the end surfaces of the upper heat preservation felt 10 and the lower heat preservation felt 14, which are positioned at the air outlet port of the air flow channel 19, are connected with the downstream heat insulation cover 24. The upper blanket 10, lower blanket 14, upstream heat shield 22 and downstream heat shield 24 collectively form a surface that mates with the circular bell of an epitaxial reactor apparatus.

In a specific embodiment of the present disclosure, the upstream heat shield 22 and the downstream heat shield 24 are both provided with a plurality of circular through holes for inserting the quartz tubules and fixing the quartz tubules to the circular bell jar structure of the epitaxial reaction apparatus. The heat shield air inlets formed on the upstream heat shield 22 and the downstream heat shield 24 are both square grooves for connecting quartz square tubes for reaction air inlet and outlet, and can also play a role in fixing the extension reaction chamber, so that the extension reaction chamber cannot swing left and right.

In order to obtain the rotation speed of the tray base 25 directly, the speed measuring device further includes a speed counter for calculating the rotation speed of the tray base 25 at the frequency of the signal periodically blocked by the speed measuring impeller. The speedometer can be provided separately or can be coupled to the signal receiver 26. The tray base speed measuring equipment disclosed by the invention can obtain accurate rotating speed information of the tray base 25, so that quick information feedback can be conveniently made on epitaxial growth reaction on the tray base 25, and the tray base speed measuring equipment has the characteristics of high adjusting precision, sensitive reaction and simple structure.

The terms "first" and "second," and the like in the description and claims of the present invention and the above-described drawings are used for distinguishing between different objects and not for describing a particular order. Furthermore, the terms "include" and "have," as well as any variations thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not set forth for a listed step or element but may include steps or elements not listed.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (10)

1. A tray base speed measuring equipment, characterized by comprising:

the epitaxial reaction chamber is provided with an air inlet port, an air outlet port and an air flow channel (19) which is communicated with the air inlet port and the air outlet port and used for flowing of reaction gas, wherein the air inlet port and the air outlet port are respectively arranged at two ends of the epitaxial reaction chamber;

the epitaxial reaction chamber comprises a tray base (25) used for bearing a substrate and rotatably arranged in the epitaxial reaction chamber, the airflow channel (19) flows through the tray base (25), a speed measuring impeller synchronously rotating with the tray base (25) is arranged below the tray base (25), and the speed measuring impeller is positioned outside the airflow channel (19);

the speed measuring device comprises a signal transmitter (23) and a signal receiver (26), wherein the signal transmitter (23) and the signal receiver (26) are respectively arranged at two ends of the epitaxial reaction chamber, and the signal receiver (26) is used for receiving signals periodically shielded by the speed measuring impeller.

2. The tray base velocimetry apparatus of claim 1, wherein said velocimetry impeller comprises:

a central rotating shaft (16) which is arranged below the tray base (25) and is coaxial with the rotating center of the tray base (25);

the speed measuring blades (17) are arranged on the central rotating shaft (16) and are two blades which are centrosymmetric along the axis of the central rotating shaft (16).

3. The tray base velocimetry apparatus according to claim 2, characterized in that the surface of said central spindle (16) is coated with a high temperature resistant coating; and/or the presence of a gas in the gas,

the surface of the speed measuring blade (17) is coated with a high-temperature resistant coating.

4. The apparatus according to claim 1, wherein said epitaxial reaction chamber comprises an upper graphite layer (11) and a lower graphite layer (13);

the airflow channel (19) is formed between the upper graphite layer (11) and the lower graphite layer (13), a tray mounting surface for mounting the tray base (25) is arranged on one side, facing the upper graphite layer (11), of the lower graphite layer (13), and a lower graphite cavity (18) for accommodating the speed measuring impeller is formed in the lower graphite layer (13).

5. The tray base velocimetry apparatus according to claim 4, wherein said upper graphite layer (11) and said lower graphite layer (13) are both of a trapezoidal cavity structure, the bottom of said upper graphite layer (11) with a larger length is a first channel side wall, the bottom of said lower graphite layer (13) with a larger length is a second channel side wall, said first channel side wall and said second channel side wall are arranged in parallel, and said air flow channel (19) is formed therebetween.

6. The tray base velocimetry device of claim 5, wherein the first channel side wall and the second channel side wall are connected by a sealing end plate, the sealing end plate comprising a first sealing end plate (12) and a second sealing end plate (20), the first sealing end plate (12) being sealingly connected to a first side of the first channel side wall and a first side of the second channel side wall, respectively, the first side of the first channel side wall and the first side of the second channel side wall being on the same side of the centre of rotation of the tray base (25);

the second sealing end plate (20) is respectively connected with the second side of the first channel side wall and the second side of the second channel side wall in a sealing way, and the second side of the first channel side wall and the second side of the second channel side wall are positioned on the same side of the rotation center of the tray base (25);

the first sealing end plate (12) and the second sealing end plate (20) are arranged along the extending direction of the airflow channel (19).

7. The tray substrate velocimetry apparatus of claim 5, wherein the epitaxial reaction chamber further comprises:

the heat preservation felt is arranged on the outer surfaces of the upper graphite layer (11) and the lower graphite layer (13);

the upstream heat shield (22) is arranged at one end of an air inlet port of the epitaxial reaction chamber and is connected with the heat preservation felt, and a heat shield air inlet communicated with the air inlet port and a first signal through hole for a signal sent by the signal transmitter (23) to pass through are formed in the upstream heat shield (22);

the downstream heat shield (24) is arranged at one end of the air outlet port of the epitaxial reaction chamber and is connected with the heat preservation felt, and a heat shield air outlet communicated with the air outlet port and a second signal through hole for passing a signal sent by the signal transmitter (23) are formed in the downstream heat shield (24).

8. The tray base velocimetry apparatus of claim 7 in which said insulation blanket comprises:

the upper heat-preservation felt (10) is sleeved on the upper graphite layer (11), and the inner surface of the upper heat-preservation felt is a surface matched with the outer surface of the upper graphite layer (11);

and the lower heat-preservation felt (14) is sleeved on the lower graphite layer (13), and the inner surface of the lower heat-preservation felt is matched with the outer surface of the lower graphite layer (13).

9. The tray base velocimetry apparatus of claim 8, characterized in that the outer surfaces of said upper insulation blanket (10) and said lower insulation blanket (14) are both semi-cylindrical surfaces.

10. A pallet base tachometer apparatus according to any of claims 1 to 9 wherein the tachometer means further comprises a tachometer for calculating the rotational speed of the pallet base (25) at the frequency of the signal periodically obscured by the tachometer impeller.

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