CN-224227287-U - Beam source furnace capable of displaying temperature distribution

CN224227287UCN 224227287 UCN224227287 UCN 224227287UCN-224227287-U

Abstract

The utility model relates to the technical field of molecular beam epitaxial film growth equipment, in particular to a beam source furnace capable of displaying temperature distribution, which mainly comprises a crucible, a heat insulation layer, a crucible supporting table and a heating sleeve arranged around the crucible, wherein a fiber bragg grating temperature sensor is arranged between the crucible and the heating sleeve and is used for monitoring temperature data of the crucible in parallel along the axis direction of the crucible, gratings are inscribed on fiber cores of the fiber bragg grating temperature sensor, the number of the gratings is set according to the length requirement of the crucible and used for obtaining temperature distribution conditions of different height areas of the crucible in a segmented or continuous mode, and the fiber bragg grating temperature sensor is connected with a multichannel spectrum demodulator and used for analyzing wavelength changes of the gratings in real time and generating longitudinal temperature distribution data of the crucible. The comprehensive monitoring of the temperature distribution of the beam source furnace is realized, and the quality and the process stability of the epitaxial film are improved by aid of power.

Inventors

WANG SHANLI
TAO XIANTONG
LI ZHUANGZHUANG
Duan Yingrui
SONG LIYUAN
YANG CHUNZHANG
JI RONGBIN
ZHAO JUN
YANG JIN
Cheng Zengci
LI YANHUI
KONG JINCHENG

Assignees

昆明物理研究所

Dates

Publication Date: 20260512
Application Date: 20250428

Claims (9)

1. The beam source furnace capable of displaying temperature distribution comprises a crucible (1), a heat insulation layer, a crucible supporting table (2) and a heating sleeve (4) arranged around the crucible (1), and is characterized in that a fiber bragg grating temperature sensor (13) is arranged between the crucible (1) and the heating sleeve (4), and the fiber bragg grating temperature sensor (13) is arranged in parallel along the axis direction of the crucible (1) and is used for monitoring temperature data of the crucible (1); A grating (1301) is inscribed on the fiber core of the fiber grating temperature sensor (13), and the grating (1301) is used for acquiring temperature data of different height areas of the crucible (1) in a segmented or continuous mode; The fiber grating temperature sensor (13) is connected with a multichannel spectrum demodulator and is used for analyzing the wavelength change of the grating (1301) in real time and generating longitudinal temperature distribution data of the crucible (1).
2. The beam source furnace capable of displaying temperature distribution according to claim 1, wherein the fiber bragg grating temperature sensors (13) are distributed in a staggered manner along the axis direction of the crucible (1) and cover different longitudinal detection areas of the crucible (1); The grating (1301) spacing of the plurality of fiber grating temperature sensors (13) can be independently adjusted, and the fiber grating temperature sensors are used for realizing segmented or continuous temperature monitoring and synchronously analyzing through a multichannel spectrum demodulator to generate high-density axial temperature distribution data.
3. The beam source furnace capable of displaying temperature distribution according to claim 1, wherein the heat insulation layer comprises a first layer heat insulation sleeve (5), a second layer heat insulation sleeve (6), a third layer heat insulation sleeve (7), a first layer heat insulation sheet (8), a second layer heat insulation sheet (9) and a third layer heat insulation sheet (10); The first layer of heat-insulating sleeve (5), the second layer of heat-insulating sleeve (6) and the third layer of heat-insulating sleeve (7) are sequentially sleeved on the outer side of the heating sleeve (4) and used for reducing heat radiation outwards; The first layer of heat insulation sheet (8), the second layer of heat insulation sheet (9) and the third layer of heat insulation sheet (10) are respectively arranged at the bottoms of the first layer of heat insulation sleeve (5), the second layer of heat insulation sleeve (6) and the third layer of heat insulation sleeve (7) and form a heat insulation cavity through welding; A supporting part (501) of a heating sleeve fixing ring is fixed on the inner side of the first layer of heat insulation sleeve (5) and is used for supporting the heating sleeve (4); The top of the first layer of heat insulation sleeve (5), the top of the second layer of heat insulation sleeve (6) and the top of the third layer of heat insulation sleeve (7) are welded with top plates (18) to form a closed heat insulation structure; And PBN insulating pieces (12) are arranged between the layers of heat insulating sleeves and between the layers of heat insulating sheets for reducing heat transfer.
4. The beam source furnace capable of displaying temperature distribution according to claim 3, wherein a heating sleeve fixing ring (401) is fixedly connected to a supporting part (501) of a heating sleeve fixing ring of the first layer of heat insulation sleeve (5), and the heating sleeve fixing ring (401) is used for installing a heating sleeve (4) and a fiber bragg grating temperature sensor (13); The heating sleeve fixing ring (401) is fixedly connected with a heat insulation material, a through hole is formed in the heating sleeve fixing ring (401), and the fiber bragg grating temperature sensor (13) is arranged in the through hole in a penetrating mode.
5. The beam source furnace capable of displaying temperature distribution according to claim 1, wherein the crucible supporting table (2) comprises a supporting rod (201) and a supporting base (202); The top of the supporting rod (201) is connected with the crucible supporting table (2), the bottom of the supporting rod is connected with the supporting base (202), and the supporting rod (201) sequentially penetrates through the third layer of heat insulation sheet (10), the second layer of heat insulation sheet (9) and the first layer of heat insulation sheet (8) to locate the crucible supporting table (2) inside the heating sleeve (4).
6. The beam source furnace capable of displaying temperature distribution according to claim 5, wherein the support base (202) is fixedly connected with a flange (3) to provide support for the whole beam source furnace.
7. The beam source furnace capable of displaying temperature distribution according to claim 6, wherein one end of the fiber bragg grating temperature sensor (13) sequentially penetrates through the flange (3), the supporting base (202), the bottom heat insulation layer and the heating sleeve fixing ring (401) and is connected with the top plate (18), the other end of the fiber bragg grating temperature sensor is connected with the multichannel spectrum demodulator, and the fiber bragg grating temperature sensor (13) is fixed between the crucible (1) and the heating sleeve (4) through a fixing piece (17) and is prevented from being in direct contact with the heating sleeve (4) or the crucible (1).
8. The beam source furnace capable of displaying temperature distribution according to claim 7, wherein the heating sleeve (4) is connected with a lead (402), and the lead (402) sequentially passes through the flange (3), the supporting base (202) and the bottom heat insulation layer and is connected with the bottom of the heating sleeve (4) to provide a heating power supply; The lead (402) is internally coated with a lead protecting sleeve (403) in the heat insulation layer, and is used for isolating heat and preventing damage to the lead (402).
9. The beam source furnace capable of displaying temperature distribution according to claim 8, wherein a fixing piece (17) is arranged at the joint of the fiber bragg grating temperature sensor (13) and the lead wire (402) and the flange (3), the fixing piece (17) is a sealing fixing piece, and sealing is formed between the fiber bragg grating temperature sensor (13) and the lead wire (402) and the flange (3).

Description

Beam source furnace capable of displaying temperature distribution Technical Field The utility model relates to the technical field of molecular beam epitaxy film growth equipment, in particular to a beam source furnace capable of displaying temperature distribution. Background In molecular beam epitaxy (Molecular Beam Epitaxy, MBE) film growth techniques, a beam source furnace serves as a core component, carrying the critical function of heating and evaporating solid source material to produce a directed beam. The traditional beam source furnace is generally composed of a cylindrical crucible, a heating wire wound outside the crucible, a metal heat insulation cylinder wrapping the heating wire, a metal thermocouple for measuring temperature and a supporting structure. The working principle is that the crucible is heated by applying electric power to the heating wire, the internal source material is evaporated to form beam flow after obtaining enough energy, and the beam flow is sprayed to the surface of the substrate through the furnace mouth of the beam source furnace to finish the epitaxial growth of the film. In this process, the thermocouple is usually fixed at a position (such as the bottom or the side wall) outside the crucible, and the heating power is regulated by a single-point temperature feedback signal, so as to control the temperature of the beam source furnace and the beam intensity. Such beam source furnaces have evolved over the years to become a standardized component of molecular beam epitaxy thin film growth equipment, each of which is typically configured with multiple beam source furnaces to accommodate different material systems. The beam current directly determines the component proportion and the growth rate of the epitaxial film, and the beam current regulation and control mainly depends on the temperature of a beam source furnace and the state of endogenous materials in a crucible. However, the prior art has the following problems: 1. The traditional thermocouple can only acquire temperature data of a certain local position of the crucible, and cannot reflect the longitudinal or radial temperature distribution of the beam source furnace. With the consumption of source materials, the form of the evaporation surface and the distribution of the thermal field can be dynamically changed, so that the single-point temperature measurement value has deviation from the actual working condition. Such deviations tend to induce beam fluctuations that in turn affect film composition uniformity and growth rate stability. 2. During long-term use, the endogenous material of the crucible is gradually reduced, and the evaporation surface can be recessed or agglomerated, so that the evaporation dynamics are changed. The prior art lacks an effective monitoring means for the state change of the source material, can only be indirectly inferred through experience or post analysis, and is difficult to realize real-time optimization of the process. 3. The furnace mouth of the beam source furnace continuously radiates heat to the cavity in the high-temperature evaporation process, and residues are easily formed at the furnace mouth of the beam source furnace which is not provided with a high-temperature protection device. Such residues not only interfere with the beam path, but also may contaminate the film surface, but at present, only can be inspected manually and visually through a viewing window, and have the problems of strong subjectivity, delayed response and the like. 4. In order to acquire temperature distribution information, the prior art tries to arrange a plurality of thermocouples at different positions of a beam source furnace, but is limited by flange space and lead installation difficulty, and practical implementation is difficult. The layout of the thermocouples not only increases the structural complexity, but also can introduce risks such as lead interference, insulation failure and the like, and reduces the reliability of the system. In summary, the shortcomings of the conventional beam source furnace in temperature monitoring and state feedback severely restrict the precise control and repeatability of the MBE process. Therefore, an integrated technology capable of comprehensively acquiring the temperature distribution of the beam source furnace in real time and synchronously monitoring the source material state and the furnace mouth working condition is required to be developed, and the quality and the process stability of the epitaxial film are improved. Disclosure of Invention In order to solve the defects in the prior art, the utility model provides a beam source furnace capable of displaying temperature distribution. Through arranging fiber bragg grating temperature sensors between the crucible and the heating sleeve, the fiber bragg gratings are arranged in parallel along the axis, the fiber bragg gratings are inscribed in the fiber cores, the temperature data of different height