Substrate temperature monitoring structure and substrate temperature monitoring method in MBE equipment

Abstract

The invention provides a substrate temperature monitoring structure and a substrate temperature monitoring method in MBE equipment, the substrate temperature monitoring structure comprises a substrate bearing structure, a measuring structure and a data processing module, the substrate bearing structure comprises a magnetic source part and a bearing part used for bearing a substrate, and the magnetic source part is embedded in a preset position of the bearing part; the measuring structure is fixed in a magnetic field generated by the magnetic source part right above the bearing part, and a preset distance is formed between the measuring structure and the upper surface of the bearing part; the measuring structure comprises a field intensity measuring part and a temperature measuring part fixed on the surface of the field intensity measuring part; the data processing module receives potential difference signals of the two poles of the field intensity measuring part and the temperature measuring part in real time and processes the two received potential difference signals in real time. The magnetic source part is arranged at the center of the bearing part, and the field intensity measuring part for measuring the magnetic field intensity and the temperature measuring part for measuring the temperature of the field intensity measuring part are arranged above the magnetic source part, so that the temperature of the substrate is accurately monitored in real time, and the cost is low.

Description

Technical Field

[0001] The invention belongs to the technical field of molecular beam epitaxy, and relates to a substrate temperature monitoring structure and a substrate temperature monitoring method in an MBE device. Background Art

[0002] Molecular Beam Epitaxy (MBE) is an epitaxial growth technology performed in an ultra-high vacuum environment. It has the characteristics of low-temperature growth and good quality of grown films. In addition, the crystallization state of the film can be monitored in real time during the film growth process.

[0003] At present, in MBE equipment, the substrate wafer is usually heated by thermal radiation, and the temperature of the substrate wafer is monitored by using a C-type thermocouple located directly below the heating structure and at a preset distance directly above the substrate wafer, such as Figure 1 and Figure 2 As shown, they are the structural diagram of the MBE equipment and the structural diagram of the heating structure, C-type thermocouple and wafer tray area in the MBE equipment, including process chamber 01, material source 02, wafer supporting structure 03, wafer tray 04, heating structure 05 and C-type thermocouple 06. The C-type thermocouple usually infers the temperature at the C-type thermocouple based on the potential difference between the two poles of the C-type thermocouple, and uses this temperature as the temperature of the substrate wafer. However, there is a certain deviation between this temperature and the actual temperature of the substrate wafer on the wafer tray in the wafer supporting structure. At the same time, as the power of the heating wire in the heating structure increases, the temperature difference between the measured temperature and the actual temperature of the substrate wafer on the wafer tray becomes larger and larger, and the change of this temperature difference is nonlinear, which makes it difficult to accurately correct the deviation of the monitored temperature, resulting in poor repeatability of the process; in addition, the measurement of the temperature of the substrate wafer can also The temperature of the substrate wafer can be measured by using an infrared temperature sensor or band-edge absorption spectrum, but the infrared light radiated by the heating wire will penetrate the sample, causing the infrared thermometer to measure it, making the measured temperature inaccurate and of little practical use. Although the non-contact measurement method of measuring temperature by band-edge absorption spectrum can monitor the temperature of the substrate wafer surface in real time, the temperature after correction is very accurate, but its supporting instruments are expensive and need to be equipped with a corresponding spectrometer according to the band gap of the sample being tested. At the same time, if the grown structure is relatively complex, it will affect the absorption spectrum, which will also affect the temperature measurement, resulting in large errors.

[0004] Therefore, there is an urgent need to find a substrate temperature monitoring structure that is low-cost, easy to operate, and capable of real-time and accurate measurement. Summary of the invention

[0005] In view of the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a substrate temperature monitoring structure and a substrate temperature monitoring method in an MBE device, so as to solve the problem that the low-cost temperature measurement structure in the prior art MBE device has a large measurement error, while the precise temperature measuring device is expensive and cumbersome to operate.

[0006] To achieve the above objectives and other related objectives, the present invention provides a substrate temperature monitoring structure, comprising:

[0007] A substrate carrying structure, comprising a magnetic source portion and a carrying portion for carrying the substrate, wherein the magnetic source portion is embedded in a preset position of the carrying portion;

[0008] A measuring structure, fixed in the magnetic field generated by the magnetic source part just above the carrying part and spaced a preset distance from the upper surface of the carrying part, the measuring structure comprising a field strength measuring part and a temperature measuring part fixed on the surface of the field strength measuring part;

[0009] The data processing module receives in real time the potential difference signal of the two poles of the field intensity measurement part and the potential difference signal of the two poles of the temperature measurement part in the measurement structure, and processes the received potential difference signal in real time.

[0010] Optionally, the bearing portion rotates around a central axis of the bearing portion, and the measuring structure is in a stationary state relative to the magnetic source portion.

[0011] Optionally, the magnetic source portion is embedded in the center of the bearing portion, and a magnetic pole of the magnetic source portion is exposed on the upper surface of the bearing portion.

[0012] Optionally, the relationship between the magnetic field intensity generated by the magnetic source part and the temperature of the surface of the bearing part is B=f(T 实 ), where T 实 is the surface temperature of the bearing portion, and B is the magnetic field intensity generated by the magnetic source portion.

[0013] Optionally, the magnetic source unit includes a permanent magnet; the field intensity measurement unit includes a Hall element; and the temperature measurement unit includes a temperature measuring thermocouple.

[0014] Optionally, the relationship between the potential difference signal between the two electrodes of the field intensity measurement unit and the magnetic field strength generated by the magnetic source unit is V=k(T)B, wherein V is the potential difference of the field intensity measurement unit under temperature T and magnetic field B, T is the actual temperature of the field intensity measurement unit obtained by the data processing unit based on the potential difference signal between the two electrodes of the temperature measurement unit, and K H (T) is the relationship between the sensitivity of the field intensity measuring unit and the temperature T.

[0015] Optionally, the substrate supporting structure is further provided with a heat source portion fixed above the supporting portion and spaced a preset distance from the supporting portion.

[0016] Optionally, the heat source portion includes a heating wire.

[0017] The present invention also provides a method for monitoring substrate temperature in an MBE device, comprising the following steps:

[0018] Providing an MBE device, wherein the substrate temperature monitoring structure in the MBE device adopts the substrate temperature monitoring structure described above;

[0019] The MBE device is turned on, and the data processing module receives and processes the potential difference signal between the two electrodes of the temperature measuring part in real time to obtain the real-time temperature of the field intensity measuring part;

[0020] The data processing module collects the potential difference signal between the two poles of the field strength measurement unit in real time and processes it in combination with the obtained real-time temperature of the field strength measurement unit to obtain the real-time field strength generated by the magnetic source unit;

[0021] The data processing module performs processing based on the relationship between the real-time magnetic field intensity and the temperature generated by the magnetic source part to obtain the real-time temperature of the magnetic source part and the substrate.

[0022] Optionally, the MBE device is further provided with a display unit, and the display unit is used to display in real time the real-time temperature of the substrate obtained by the data processing module.

[0023] As described above, the substrate temperature monitoring structure and the substrate temperature monitoring method in the MBE device of the present invention are achieved by improving the substrate temperature monitoring structure, setting a magnetic source part at the center of the bearing part, and setting a measuring structure in the magnetic field at a preset distance directly above the magnetic source part, and the temperature measuring part in the measuring structure is fixed on the field strength measuring part, and a data processing module is used to receive the potential difference signal between the two poles of the field strength measuring part and the potential difference signal between the two poles of the temperature measuring part in real time, and the difference between the two received potential signals is processed to obtain the magnetic field strength generated by the magnetic source part, and then the temperature of the substrate is obtained based on the relationship between the magnetic field strength generated by the magnetic source part and the temperature, thereby realizing real-time and accurate monitoring of the substrate temperature, providing convenience for process debugging, ensuring the repeatability of the process, improving the process yield, and facilitating the growth of batch film layers, and each component of the structure is low in price and simple to operate, and has high industrial utilization value. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Shown is a block diagram of the MBE device.

[0025] Figure 2A structural diagram showing the area where the heating structure, thermocouples, and wafer tray are located in the MBE equipment.

[0026] Figure 3 Shown is a schematic structural diagram of the substrate temperature monitoring structure of the present invention.

[0027] Figure 4 It is a three-dimensional structural schematic diagram showing a partial structure of the substrate temperature monitoring structure of the present invention.

[0028] Figure 5 A top view of a substrate supporting structure of the substrate temperature monitoring structure of the present invention is shown.

[0029] Figure 6 Shown is a process flow chart of a substrate temperature monitoring method in an MBE device of the present invention.

[0030] Description of Figure Numbers

[0031] 01 Process Chamber

[0032] 02 Material Source

[0033] 03 Wafer support structure

[0034] 04 Wafer Tray

[0035] 05 Heating structure

[0036] 06 Thermocouple

[0037] 1 Substrate support structure

[0038] 11 Load-bearing unit

[0039] 12 Magnetic source

[0040] 121 N pole

[0041] 122 S pole

[0042] 13 Substrate placement hole

[0043] 2 Measurement structure

[0044] 21 Field Strength Measurement Department

[0045] 22. Temperature measurement unit

[0046] 3 Data Processing Module DETAILED DESCRIPTION

[0047] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0048] See also Figures 3 to 6 It should be noted that the illustrations provided in this embodiment are only used to illustrate the basic concept of the present invention in a schematic manner, and the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0049] Embodiment 1

[0050] This embodiment provides a substrate temperature monitoring structure. Figures 3 to 5 ,like Figure 3 and Figure 4 As shown, they are respectively a structural schematic diagram of the substrate temperature monitoring structure and a three-dimensional structural schematic diagram of a partial structure of the substrate temperature monitoring structure, including a substrate supporting structure 1, a measuring structure 2 and a data processing module 3, wherein the substrate supporting structure 1 includes a magnetic source part 12 and a supporting part 11 for supporting a substrate, and the magnetic source part 12 is embedded in a preset position of the supporting part 11; the measuring structure 2 is fixed in the magnetic field generated by the magnetic source part 12 directly above the supporting part 11 and is spaced a preset distance from the upper surface of the supporting part 11, and the measuring structure 2 includes a field strength measuring part 21 and a temperature measuring part 22 fixed on the surface of the field strength measuring part 21; the data processing module 3 receives in real time the potential difference signals of the two poles of the field strength measuring part 21 and the potential difference signals of the two poles of the temperature measuring part 22 in the measuring structure 2, and processes the received potential difference signals in real time.

[0051] Specifically, the substrate supporting structure 1 is mainly used to support the substrate for molecular beam epitaxy process. Since the material source of MBE is usually at the bottom, the side of the substrate to be grown with the film layer needs to face downward, that is, the process side of the substrate faces downward, to facilitate the epitaxial process.

[0052] As an example, Figure 5 As shown, it is a top view of the substrate supporting structure 1 , the supporting part 11 rotates around the central axis of the supporting part 11 , and the measuring structure 2 is in a stationary state relative to the magnetic source part 12 , so as to facilitate the measurement of the magnetic field strength generated by the magnetic source part 12 by the measuring structure 2 .

[0053] It should be noted that the supporting part 11 is used to fix the substrate. During the molecular beam epitaxy process, in order to achieve uniformity of composition and temperature of the sample, the supporting part 11 needs to be rotating. Therefore, while the supporting part 11 carries the substrate, the substrate it carries also needs to be fixed so that the substrate rotates at a uniform speed with the supporting part 11.

[0054] Specifically, the carrying part 11 is fixed to the bottom end of the substrate carrying structure 1, and the carrying part 11 can rotate at a uniform speed around the central axis of the carrying part 11 along with the substrate carrying structure 1. Then, driven by the carrying part 11, the substrate rotates at a uniform speed around the central axis of the carrying part 11 along with the substrate carrying structure 1.

[0055] It should be noted that the method of fixing the bearing part 11 to the substrate bearing structure 1 can be selected according to actual conditions. For example, in order to facilitate the disassembly of the bearing part 11, a structure for fixing the bearing part 11 can be provided at the bottom end of the substrate bearing structure 1 to achieve the fixation of the bearing part 11. Preferably, a plurality of hooks for fixing the bearing part 11 are provided at the edge of the bottom end of the substrate bearing structure 1, and the bearing part 11 is fixed by the hooks.

[0056] Specifically, the carrying portion 11 includes at least one substrate placement hole 13 that penetrates the carrying portion 11, the substrate placement hole 13 is spaced a preset distance from the center of the carrying portion 11, and the substrate placement hole 13 is spaced a preset distance from the magnetic source portion 12. Penetration here means penetrating the carrying portion 11 in a direction perpendicular to the upper surface of the carrying portion 11, that is, penetrating the carrying portion 11 from top to bottom or from bottom to top.

[0057] Specifically, the size, shape and thickness of the bearing part 11 are related to the process requirements and are not limited here; the distance between the substrate placement hole 13 and the center of the bearing part 11 can be selected according to actual conditions; the size, number, shape and distribution of the substrate placement holes 13 can be selected according to actual conditions; the distance between the substrate placement holes 13 and the magnetic source part 12 can be selected according to actual conditions. In this embodiment, the bearing part 11 is disc-shaped, and the bearing part 11 is provided with 4 substrate placement holes 13 that surround the center of the bearing part 11 and are evenly distributed.

[0058] As an example, the magnetic source portion 12 is embedded in the center of the carrier portion 11 , and a magnetic pole of the magnetic source portion 12 is exposed on the upper surface of the carrier portion 11 .

[0059] Specifically, since the bearing part 11 rotates around its central axis, the center position of the bearing part 11 does not shift relative to the central axis of the bearing part 11. The magnetic source part 12 is arranged at the center of the bearing part 11 so that the position of the magnetic source part 12 does not change, thereby ensuring the stability of the magnetic field provided by the magnetic source part 12.

[0060] Specifically, a magnetic pole of the magnetic source portion 12 is exposed on the upper surface of the carrier portion 11 to prevent the material of the carrier portion 11 from affecting the strength of the magnetic field generated by the magnetic source portion 12, and then affecting the potential difference signal generated between the two poles of the field strength measurement portion 21 in the measurement structure 2, thereby resulting in a large error between the substrate temperature processed by the data processing module 3 and the actual temperature of the substrate.

[0061] Specifically, under the condition that the magnetic source part 12 is exposed on the upper surface of the bearing part 11, the upper surface of the magnetic source part 12 can be lower than the upper surface of the bearing part 11, or it can be flush with the upper surface of the bearing part 11, or it can protrude from the upper surface of the bearing part 11 by a preset distance; the magnetic source part 12 can penetrate the bearing part 11, or it can be embedded only in the upper surface layer at the center of the bearing part 11. In this embodiment, the upper and lower surfaces of the magnetic source part 12 are flush with the upper and lower surfaces of the bearing part 11, that is, the magnetic source part 12 penetrates the center of the bearing part 11, so that the temperature of the entire bearing part 11 is the same as that of the magnetic source part 12, thereby reducing the temperature difference between the two and reducing the measurement error.

[0062] It should be noted that the magnetic source part 12 usually works in a high temperature environment. In order to ensure the measurement accuracy, the magnetic source part 12 needs to have high temperature resistance and be able to generate a magnetic field of stable strength in a high temperature environment, so as to determine the temperature of the environment in which the magnetic source part 12 is located through the magnetic field strength.

[0063] As an example, the magnetic source 12 includes a permanent magnet or other magnetic field generating components suitable for working in a high temperature environment. For example, a cylindrical magnetic steel (also called aluminum nickel cobalt alloy or AlNiCo magnet) is used as the magnetic source 12, wherein the residual magnetism temperature coefficient of the magnetic steel is Among them, α(T) is the residual magnetism temperature coefficient, T is the temperature value of the magnetic steel, T0 is the reference temperature value, B r (T) is the remanence value at temperature T, B r (T0) is the residual magnetism value at reference temperature T0. The high temperature environment here refers to a temperature environment of not less than 400°C.

[0064] Specifically, the size and shape of the magnetic source part 12 can be selected according to actual conditions while ensuring that the magnetic source part 12 can generate a magnetic field of stable strength; the operating temperature range of the magnetic source part 12 can be selected according to actual conditions. Preferably, the magnetic source part 12 is cylindrical.

[0065] Specifically, the magnetic pole exposed on the upper surface of the carrying portion 11 can be selected according to actual conditions, for example, it can be an N pole or an S pole. In this embodiment, the magnetic source portion 12 runs through the central area of ​​the carrying portion 11, the magnetic pole exposed on the upper surface of the carrying portion 11 is an N pole 121, and the magnetic pole exposed on the lower surface of the carrying portion 11 is an S pole 122.

[0066] Specifically, the field strength measuring unit 21 in the measurement structure 2 is used to measure the field strength generated by the magnetic source unit 12. While ensuring the uniformity of the magnetic field strength of the environment in which the field strength measuring unit 21 is located, the distance between the magnetic source unit 12 and the field strength measuring unit 21 can be selected according to actual conditions.

[0067] Specifically, the field strength measuring unit 21 usually has two poles for measuring the potential difference signal, and the two poles are respectively connected to the data processing module 3 to achieve the transmission of the potential difference signal between the two poles of the field strength measuring unit 21.

[0068] As an example, the field strength measuring unit 21 includes a Hall element or other magnetic field strength measuring devices suitable for high temperature environments. Preferably, a Hall element capable of operating at high temperatures is used as the field strength measuring unit 21. For example, a gallium nitride Hall element.

[0069] Specifically, the field strength measuring unit 21 is used to measure the magnetic field strength in a high temperature environment. Its electrical properties in a high temperature environment are known or can be obtained through experimental tests. While ensuring the accuracy of the field strength measured by the field strength measuring unit 21, the size and shape of the field strength measuring unit 21 can be selected according to actual conditions.

[0070] Specifically, the temperature measuring unit 22 is used to measure the temperature at the field strength measuring unit 21 . The temperature measuring unit 22 is fixed to the surface of the field strength measuring unit 21 to measure the temperature of the field strength measuring unit 21 in real time.

[0071] As an example, the temperature measuring unit 22 includes a temperature measuring thermocouple or other suitable real-time temperature measuring devices. Preferably, a C-type thermocouple is used as the temperature measuring unit 22 .

[0072] Specifically, while ensuring the accuracy of the temperature measured in a high temperature environment, the size and shape of the temperature measuring portion 22 can be selected according to actual conditions. For example, it can be cylindrical.

[0073] It should be noted that when a thermocouple is used as the temperature measuring part 22 to measure temperature, the temperature measuring part 22 usually has two poles for measuring the potential difference signal, and the two poles are respectively connected to the data processing module 3 to realize the transmission of the potential difference signal between the two poles of the temperature measuring part 22.

[0074] Specifically, the data processing module 3 is used to process the potential difference signal fed back in real time by the field strength measurement unit 21 and the temperature measurement unit 22 in the measurement structure 2. The data processing module 3 usually receives the potential difference signal fed back by the temperature measurement unit 22 and the field strength measurement unit 21 through a high temperature resistant connecting line.

[0075] Specifically, the data processing module 3 includes a chip circuit, a computer or other suitable signal processing device with signal processing capability; while ensuring the signal processing capability of the data processing module 3, the position and size of the data processing module 3 can be selected according to actual conditions.

[0076] As an example, the relationship between the magnetic field intensity generated by the magnetic source portion 12 and the surface temperature of the carrying portion 11 is B=f(T 实 ), where T 实 is the surface temperature of the carrier portion 11 , and B is the magnetic field intensity generated by the magnetic source portion 12 .

[0077] It should be noted that the relationship between the temperature of the magnetic source part 12 and the surface of the carrier part 11 is determined by the temperature characteristics of the magnetic source part 12, and the temperature characteristics of the magnetic source part 12 are usually affected by the material, size, shape and annealing temperature of the magnetic source part 12. The temperature characteristics of the magnetic source part 12 of the same shape and size but different materials are usually different, but the magnetism of the magnetic source part 12 decreases with the increase of temperature. Based on the material, size, shape and annealing temperature of the magnetic source part 12, it can be obtained through experiments. The relationship between the specific magnetic field intensity generated by the magnetic source part 12 and the ambient temperature in which it is located is not listed one by one here. The annealing temperature here refers to the annealing temperature of the magnetic source part 12.

[0078] Specifically, through the relationship between the magnetic field strength generated by the magnetic source part 12 and the temperature environment in which it is located, the temperature of the environment in which the magnetic source part 12 is located, that is, the temperature of the bearing part 11, can be reversely deduced based on the magnetic field strength measured by the field strength measuring part 21.

[0079] As an example, the relationship between the potential difference signal between the two electrodes of the field intensity measurement unit 21 and the magnetic field intensity generated by the magnetic source unit 12 is V=K H (T)B, where V is the potential difference between the two electrodes of the field strength measuring unit 21 under temperature T and magnetic field B, T is the actual temperature of the field strength measuring unit 21 obtained by the data processing unit 3 based on the potential difference signal between the two electrodes of the temperature measuring unit 22, and K H (T) is the relationship between the sensitivity of the field intensity measuring unit 21 and the temperature T.

[0080] It should be noted that the relationship between the potential difference signal between the two electrodes of the field strength measuring unit 21 and the sensitivity of the field strength measuring unit 21 at the temperature and the magnetic field strength generated by the magnetic source unit 12 is determined by the material of the field strength measuring unit 21 and the temperature characteristics of its sensitivity. The temperature characteristics of the sensitivity of the field strength measuring unit 21 of different materials are usually different. Based on the material, size and related structural characteristics of the field strength measuring unit 21, the relationship between the sensitivity and temperature of the field strength measuring unit 21 can be obtained through experiments, and then based on the sensitivity of the field strength measuring unit 21 and the potential difference signal between the two poles of the field strength measuring unit 21 received by the data processing module 3, the magnetic field strength generated by the magnetic source unit 12 can be reversed. Since the potential difference between the two electrodes of the field strength measuring unit 21 is related to the material of the field strength measuring unit 21 and the temperature characteristics of its sensitivity, the relationship between the potential difference signal between the two electrodes of the field strength measuring unit 21 and the magnetic field strength generated by the magnetic source unit 12 will not be listed one by one here.

[0081] Specifically, the data processing module 3 is also provided with a display unit for displaying the received potential difference signal (the potential difference signal between the two poles of the field strength measuring part 21 and the potential difference signal between the two poles of the temperature measuring part 22) and the signal processing result, so as to facilitate the visual monitoring of the substrate temperature of the epitaxial process, and at the same time, the substrate temperature can be timely adjusted based on the processing result displayed by the display unit.

[0082] It should be noted that a prompt alarm unit may also be provided in the data processing module 3. When the temperature of the load-bearing part 11 is lower than a preset value or exceeds a preset value after processing by the data processing module 3, the alarm unit is triggered to give an alarm prompt to remind the operator.

[0083] As an example, the substrate supporting structure 1 is further provided with a heat source portion fixed above the supporting portion 11 and spaced apart from the supporting portion 11 by a preset distance.

[0084] Specifically, since the substrate usually needs to be heated by thermal radiation during the process of growing the film layer by the molecular beam epitaxy process, a heat source is provided above the carrier 11 to heat the substrate by thermal radiation generated by the heat source.

[0085] As an example, the heat source portion includes a heating wire or other suitable heating devices. Preferably, a heating wire is used as the heat source portion.

[0086] It should be noted that, generally during the molecular epitaxial process, the substrate needs to be heated uniformly, so the heater in the heat source part usually needs to be evenly distributed directly above the carrier part 11 so that the heat radiated by the heat source part to each area of ​​the carrier part 11 is uniform.

[0087] Specifically, under the condition of ensuring uniform heating of the substrate by the heat source part 12, the distribution mode of the heaters in the heat source part, the size of the heaters, the number of heaters and the shape of the heaters can be selected according to actual conditions and are not limited here.

[0088] Specifically, by improving the structure of the carrying part 11, a magnetic source part 12 is set at the center position of the carrying part 11, and a measuring structure 2 is set at a preset distance directly above the magnetic source part 12. The data processing module 3 obtains the real temperature of the field strength measurement part 21 based on the potential difference signal fed back by the temperature measurement part 22, and obtains the magnetic field strength generated by the magnetic source part 12 based on the relationship between the field strength measurement part 21 and the temperature and the magnetic field strength generated by the magnetic source part 12 and the potential difference signal fed back by the field strength measurement part 21. The data processing module 3 then obtains the real temperature of the carrying part 11 based on the relationship between the magnetic field strength generated by the magnetic source part 12 and the temperature, thereby realizing the accurate measurement of the real temperature of the substrate.

[0089] Specifically, through the combination of the magnetic source unit 12, the field strength measurement unit 21, the temperature measurement unit 22 and the data processing unit 3, real-time monitoring of the actual temperature of the substrate is achieved, which makes the debugging of the molecular beam epitaxy process more convenient and ensures the repeatability of the molecular beam epitaxy process. At the same time, the yield of the process is improved, the operation is simple, and the price of each component in the monitoring structure is low, which reduces the cost of realizing real-time monitoring.

[0090] The substrate temperature monitoring structure of the present embodiment is achieved by setting a magnetic source part 12 at the center of the carrier part 11, and setting a measuring structure 2 directly above the magnetic source part 12. The data processing module 3 processes the potential difference signal fed back by the temperature measuring part 22 to obtain the actual temperature of the field strength measuring part 21. The data processing module 3 then processes the magnetic field strength generated by the magnetic source part 12 based on the potential difference signal between the two poles of the field strength measuring part 21, the relationship between the actual temperature of the field strength measuring part 21 and the sensitivity of the field strength measuring part 21, and the received potential difference signal between the two poles of the field strength measuring part 21. At the same time, the data processing module 3 processes the temperature of the carrier part 11 based on the relationship between the magnetic field strength generated by the magnetic source part 12 and the temperature and the magnetic field strength generated by the magnetic source part 12 obtained based on the potential difference signal fed back by the field strength measuring part 21, thereby realizing the accurate measurement of the actual temperature of the substrate fixed on the carrier part 11, making process debugging more convenient, ensuring the repeatability of the process, and improving the yield of the process. In addition, its components are low in price and simple to operate.

[0091] Embodiment 2

[0092] This embodiment provides a substrate temperature monitoring method in an MBE device, such as Figure 6 FIG. 1 is a process flow chart of a substrate temperature monitoring method in an MBE device, comprising the following steps:

[0093] S1: providing an MBE device, wherein the substrate temperature monitoring structure in the MBE device adopts the substrate temperature monitoring structure described above;

[0094] S2: Turn on the MBE device, and the data processing module receives and processes the potential difference signal between the two electrodes of the temperature measuring part in real time to obtain the real-time temperature of the field intensity measuring part;

[0095] S3: the data processing module receives the potential difference signal between the two poles of the field strength measuring unit in real time and processes it in combination with the real-time temperature of the field strength measuring unit to obtain the real-time field strength generated by the magnetic source unit;

[0096] S4: The data processing module performs processing based on the relationship between the real-time magnetic field intensity and temperature generated by the magnetic source part to obtain the real-time temperature of the magnetic source part and the substrate.

[0097] Specifically, perform step S1 and step S2: provide an MBE device, in which the substrate temperature monitoring structure adopts the substrate temperature monitoring structure described above; turn on the MBE device, and the data processing module 3 receives the potential difference signal between the two poles of the temperature measuring part 22 in real time and processes it to obtain the real-time temperature of the field strength measuring part 21.

[0098] It should be noted that the MBE device is a common molecular beam epitaxy device, and its model and components will not be introduced in detail here.

[0099] Specifically, when the film is grown using the molecular beam epitaxy process, it needs to be carried out in an ultra-high vacuum (UHV) environment to avoid interference from external impurities, improve the quality of the epitaxy, ensure the cleanliness of the grown film, and reduce the contamination of the film by residual gases in the process chamber. Usually, before the molecular beam epitaxy process is carried out, the vacuum degree of the process chamber needs to reach 10 -10 Torr magnitude.

[0100] Specifically, after starting the MBE equipment and before film growth, preparatory work needs to be performed, for example, fixing the substrate on the carrier 11, evacuating the process chamber, heating the substrate, etc.

[0101] It should be noted that, in the process of heating and molecular beam epitaxy of the substrate, in order to ensure the uniformity of the substrate temperature, the component that fixes the supporting part 11 in the substrate supporting structure 1 usually drives the supporting part 11 to rotate around the center of the supporting part 11, while the heat source part in the substrate supporting structure 1 is fixed. Under the condition of ensuring the uniformity of substrate heating, the rotation speed of the supporting part 11 can be selected according to actual conditions.

[0102] Specifically, the temperature measuring unit 22 is fixed on the field strength measuring unit 21, and the temperature measured by the temperature measuring unit 22 is the temperature of the field strength measuring unit 21. Under the condition of ensuring the accuracy of the actual temperature of the field strength measuring unit 21 measured by the temperature measuring unit 22, the position where the temperature measuring unit 22 is fixed on the field strength measuring unit 21 can be selected according to actual conditions. Preferably, the temperature measuring unit 22 is fixed at the center of the upper surface of the field strength measuring unit 21.

[0103] Specifically, after the device is started, the temperature measuring unit 22 usually starts to transmit the potential difference signal between its two poles to the data processing module 3 in real time. The data processing module 3 receives the potential difference signal between the two poles of the temperature measuring unit 22 fed back by the temperature measuring unit 22 in real time, and based on the relationship between the temperature of the temperature measuring unit 22 and the potential difference between its two poles, processes it to obtain the real-time temperature of the field strength measuring unit 21.

[0104] It should be noted that the potential difference signal between the two poles of the field strength measuring unit 21 usually needs to be measured by a potential difference measuring device, and the data processing module 3 performs processing based on the feedback result of the potential difference measuring device (the data of measuring the potential difference between the two poles of the temperature measuring unit 22), and the device for measuring the potential difference signal between the two poles of the field strength measuring unit 21 can be selected according to actual conditions.

[0105] Specifically, please execute step S3 and step S4: the data processing module 3 receives the potential difference signal between the two poles of the field strength measuring part 21 in real time and processes it in combination with the real-time temperature of the field strength measuring part 21 to obtain the real-time field strength generated by the magnetic source part 12; the data processing module 3 processes based on the relationship between the real-time magnetic field strength and temperature generated by the magnetic source part 12 to obtain the real-time temperature of the magnetic source part 12 and the substrate.

[0106] Specifically, after the MBE device is started, the field strength measuring unit 21 feeds back the potential difference signal between its two poles to the data processing module 3 in real time. The data processing module 3 receives the potential difference signal between the two poles of the field strength measuring unit 21 in real time, and based on the real-time temperature value of the field strength measuring unit 21 and the relationship between the sensitivity of the field strength measuring unit 21 and the temperature, obtains the sensitivity of the field strength measuring unit 21. Based on the relationship between the potential difference signal between the two poles of the field strength measuring unit 21, the sensitivity of the field strength measuring unit 21 and the magnetic field strength, obtains the real-time magnetic field strength generated by the magnetic source unit 12.

[0107] It should be noted that the potential difference signal between the two poles of the field strength measuring unit 21 usually needs to be measured by a potential difference measuring device, and the data processing module 3 performs processing based on the feedback result of the potential difference measuring device (the data of measuring the potential difference between the two poles of the field strength measuring unit 21), and the device for measuring the potential difference signal between the two poles of the field strength measuring unit 21 can be selected according to actual conditions.

[0108] Specifically, after the data processing module 3 obtains the real-time magnetic field strength generated by the magnetic source part 12, it obtains the real-time temperature of the magnetic source part 12, that is, the real-time temperature of the supporting part 11 and the substrate, based on the relationship between the magnetic field strength generated by the magnetic source part 12 and the temperature, thereby realizing real-time monitoring of the substrate temperature.

[0109] As an example, the MBE device is also provided with a display unit, which is used to display the real-time temperature of the substrate processed by the data processing module 3 in real time, so as to facilitate visual real-time monitoring of the temperature of the substrate and facilitate process debugging.

[0110] Specifically, through the combination of the temperature measuring unit 22 for measuring the temperature of the field strength measuring unit 21, the field strength measuring unit 21 for measuring the magnetic source unit 12, the magnetic source unit 12 embedded in the carrier unit 11 and the data processing module 3, real-time and high-precision monitoring of the substrate temperature is achieved, which provides convenience for process debugging, ensures the repeatability of the process, improves the yield of the process, and facilitates the growth of batch film layers.

[0111] The substrate temperature monitoring method in the MBE device of this embodiment realizes real-time and high-precision monitoring of the substrate temperature by adopting the substrate temperature monitoring structure described in Example 1, which provides convenience for process debugging, ensures the repeatability of the process, improves the process yield, and facilitates the growth of batch film layers.

[0112] In summary, the substrate temperature monitoring structure and the substrate temperature monitoring method in the MBE device of the present invention improve the temperature measurement structure, embed the magnetic source part in the center of the bearing part, and set the field strength measurement part for measuring the magnetic field strength in the magnetic field at a preset distance directly above the magnetic source part, and at the same time set the temperature measurement part for measuring the temperature of the field strength measurement part on the field strength measurement part, and use the data processing module to receive the potential difference signal between the two poles of the field strength measurement part and the potential difference signal between the two poles of the temperature measurement part in real time, and obtain the magnetic field strength generated by the magnetic source part based on the difference of the two received potential signals, and then obtain the temperature of the substrate based on the relationship between the magnetic field strength generated by the magnetic source part and the temperature, so as to realize the real-time and accurate monitoring of the temperature of the substrate, ensure the repeatability of the process, improve the yield of the process, facilitate the growth of batch film layers, and provide convenience for the debugging of the process, and the price of each component in the monitoring structure is low and the operation is simple. Therefore, the present invention effectively overcomes the various shortcomings in the prior art and has a high industrial utilization value.

[0113] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A substrate temperature monitoring structure, characterized in that: include: A substrate carrying structure, comprising a magnetic source portion and a carrying portion for carrying the substrate, wherein the magnetic source portion is embedded in a preset position of the carrying portion; A measuring structure, fixed in the magnetic field generated by the magnetic source part just above the carrying part and spaced a preset distance from the upper surface of the carrying part, the measuring structure comprising a field strength measuring part and a temperature measuring part fixed on the surface of the field strength measuring part; The data processing module receives in real time the potential difference signal of the two poles of the field intensity measurement part and the potential difference signal of the two poles of the temperature measurement part in the measurement structure, and processes the received potential difference signal in real time.

2. The substrate temperature monitoring structure according to claim 1, characterized in that: The bearing portion rotates around a central axis of the bearing portion, and the measuring structure is in a stationary state relative to the magnetic source portion.

3. The substrate temperature monitoring structure according to claim 1, characterized in that: The magnetic source part is embedded in the center of the carrying part, and a magnetic pole of the magnetic source part is exposed on the upper surface of the carrying part.

4. The substrate temperature monitoring structure according to claim 1, wherein: The relationship between the magnetic field intensity generated by the magnetic source and the temperature of the surface of the bearing portion is B=f(T 实 ), where T 实 is the surface temperature of the bearing portion, and B is the magnetic field intensity generated by the magnetic source portion.

5. The substrate temperature monitoring structure according to claim 1, characterized in that: The magnetic source unit includes a permanent magnet; the field intensity measurement unit includes a Hall element; and the temperature measurement unit includes a temperature measuring thermocouple.

6. The substrate temperature monitoring structure according to claim 1, characterized in that: The relationship between the potential difference signal between the two poles of the field intensity measurement unit and the magnetic field strength generated by the magnetic source unit is V=k(T)B, wherein V is the potential difference of the field intensity measurement unit under temperature T and magnetic field B, T is the actual temperature of the field intensity measurement unit obtained by the data processing unit based on the potential difference signal between the two poles of the temperature measurement unit, and K H (T) is the relationship between the sensitivity of the field intensity measuring unit and the temperature T.

7. The substrate temperature monitoring structure according to claim 1, characterized in that: The substrate supporting structure is also provided with a heat source portion which is fixed above the supporting portion and is spaced a preset distance from the supporting portion.

8. The substrate temperature monitoring structure according to claim 7, characterized in that: The heat source portion includes a heating wire.

9. A method for monitoring substrate temperature in an MBE device, characterized in that: The following steps are involved: Provide an MBE device, wherein the substrate temperature monitoring structure in the MBE device adopts the substrate temperature monitoring structure according to any one of claims 1 to 8; The MBE device is turned on, and the data processing module receives and processes the potential difference signal between the two electrodes of the temperature measuring part in real time to obtain the real-time temperature of the field intensity measuring part; The data processing module receives the potential difference signal between the two poles of the field strength measurement unit in real time and processes it in combination with the real-time temperature of the field strength measurement unit to obtain the real-time field strength generated by the magnetic source unit; The data processing module performs processing based on the relationship between the real-time magnetic field intensity and the temperature generated by the magnetic source part to obtain the real-time temperature of the magnetic source part and the substrate.

10. The method for monitoring substrate temperature in an MBE device according to claim 9, characterized in that: The MBE device is also provided with a display unit, and the display unit is used to display the real-time temperature of the substrate obtained by the data processing module in real time.

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