Patent ID: 12195875

DETAILED DESCRIPTION OF THE EMBODIMENTS

Reference will now be made in detail to the embodiments of the present invention, examples of which are illustrated in the accompanying drawings. It is to be understood that the present invention is to be considered as illustrative and not restrictive. All other embodiments obtained by persons of ordinary skill in the art based on the embodiments of the present invention without inventive efforts shall belong to the scope of protection of the present invention.

Referring toFIGS.1-9, the laser processing system integrated with an MBE device of the present invention comprises an MBE growth chamber1and a sample table2. An opening is formed on one side of the MBE growth chamber1. The sample table2is fixed within the MBE growth chamber1, aligning with the opening, and is used to hold a substrate sample material.

In the prior art, a substrate sample material is typically placed on a sample table2inside an MBE growth chamber1. Then, an external laser is directed by an optical path system, and light enters the MBE growth chamber1through a reserved window, focusing on the sample stage2for processing. However, the distance from the refracted optical path to the silicon-based substrate is long, resulting in poor laser focusing capability and inadequate processing precision, thereby affecting the quality of laser processing.

In the present embodiment, an optical path mechanism3, a heat insulation mechanism4, and a cooling mechanism5are incorporated. The optical path mechanism3is arranged adjacent to a side of the MBE growth chamber1and is equipped with a light emitting end. The light emitting end penetrates through the opening of the MBE growth chamber1, extends inside, and is spaced apart from the sample table2. The optical path mechanism3is hermetically sealed to the opening of the MBE growth chamber1. The heat insulation mechanism4is positioned on the side of the light emitting end of the optical path mechanism3to reduce heat radiation reaching the lens of the optical path mechanism3. The cooling mechanism5is placed on the outer side of the optical path mechanism3and includes a cooling channel through which a heat exchange medium flows, quickly dissipating the accumulated heat from the optical path mechanism3to the outside.

It's essential to note that when the MBE device grows a thin film material, it operates in an ultra-high vacuum environment of 10-7 Pa, and the temperature of the substrate sample material may reach up to 1000° C. However, the operational temperature range of an existing laser processing system is generally between −5-50° C., which is unsuitable for operation in a vacuum high-temperature environment.

The light emitting end of the optical path mechanism3extends 20 mm into the MBE growth chamber1from the substrate sample material on the sample table2.

In this embodiment, by extending the light emitting end of the optical path mechanism3into the MBE growth chamber1and sealing it with the opening of the MBE growth chamber1, the MBE growth chamber1maintains a vacuum environment. Furthermore, by minimizing heat radiation and conducting heat dissipation from the light emitting side of the optical path mechanism3through the heat insulation mechanism4and cooling mechanism5, the temperature of the light emitting end of the optical path mechanism3remains within the normal operating range. Therefore, the optical path mechanism3is integrated into the MBE device, enhancing laser focusing capability through direct laser writing, and ensuring precision and quality in laser processing.

As the laser processing system is integrated with the MBE device, the available space within the MBE device is limited, posing challenges for installation.

In this embodiment, the optical path mechanism3comprises an external optical path assembly31, an internal optical path assembly32, and an objective lens33. The external optical path assembly31penetrates through the opening of the MBE growth chamber1and extends inside, connecting to an external laser device. The internal optical path assembly32is concentrically arranged within the external optical path assembly31, extending into the MBE growth chamber1. The objective lens33, positioned at the end of the internal optical path assembly32away from the external optical path assembly31, serves as the light emitting end of the optical path mechanism3. A laser from the external laser device is reflected into the internal optical path assembly32through the external optical path assembly31, and the substrate sample material is processed through the objective lens33.

Importantly, since it's not convenient to observe the thin film material within the MBE growth chamber1, the optical path mechanism3integrates a laser processing optical path, a microscopic imaging optical path, and an ultrafast imaging optical path. The laser processing optical path is used for laser processing of the sample material, while the microscopic imaging optical path is for microscopic imaging of the material sample's surface, and the ultrafast imaging optical path is for imaging the sample with ultra-high temporal resolution.

The internal optical path assembly32in this embodiment comprises a first cylinder321, within which a first dichroscope322, a second dichroscope323, a first reflector324, a second reflector325, and a first planoconvex lens326are fixedly mounted. The first dichroscope322and the second dichroscope323are arranged in a V shape in the middle of a mounting cavity. The first reflector324is positioned adjacent to the first dichroscope322, parallel to it, while the second reflector325is placed on the opposite side of the first dichroscope322, also parallel to it. The first planoconvex lens326is positioned to correspond to the second reflector325, with a line drawn from the center point of the first planoconvex lens326to the center point of the second reflector325being parallel to the axial horizontal line of the optical path mechanism3.

The objective lens33is composed of a third cylinder331, within which a fourth cylinder332and a fifth cylinder333are securely mounted. Successively fixed within the fourth cylinder332are a first biconcave lens334, a first biconvex lens335, a second biconvex lens336, a second biconcave lens337, and a second biconvex lens338. The first biconcave lens334is positioned closest to the internal optical path assembly32. Within the fifth cylinder333, a first concave lens339, a second planoconvex lens3310, and a second concave lens3311are sequentially fixed. The first concave lens339is situated near the second biconcave lens337.

The external optical path assembly31consists of a sixth cylinder311, a seventh cylinder312, an eighth cylinder313, and a ninth cylinder314. Within the sixth cylinder311, a series of optical components are arranged, including a first optical fiber coupling lens3111, a second optical fiber coupling lens3112, a third reflector3113, a first beam splitter3114, an eyepiece3115, a second beam splitter3116, a fourth reflector3117, a third beam splitter3118, and a fifth reflector3119. The first optical fiber coupling lens3111corresponds to the first reflector324, while the second optical fiber coupling lens3112corresponds to the third reflector3113. The first beam splitter3114is centrally located within the sixth cylinder311, aligned with the eyepiece3115. Positioned close to the first beam splitter3114is the third reflector3118, which reflects a laser beam to the center point of the first beam splitter3114. The second beam splitter3116corresponds to the fourth reflector3117, reflecting light back from the sample table2. The third beam splitter3118corresponds to both the fourth reflector3117and the fifth reflector3119. Additionally, a set of optical components are arranged within the seventh cylinder312, including a third optical fiber coupling lens3121, a sixth reflector3122, a grating3123, a third planoconvex lens3124, a fourth optical fiber coupling lens3125, a fourth planoconvex lens3126, and a fifth planoconvex lens3127. Furthermore, a sixth planoconvex lens3131, a CCD camera3132, and a diaphragm3133are arranged within the eighth cylinder313, while a seventh planoconvex lens3141is placed within the ninth cylinder314.

The external optical path assembly31also incorporates an external laser device, a frequency multiplier, and a photonic crystal transmission optical fiber.

In the laser processing optical path, a laser is emitted by its laser device, transmitted to the first optical fiber coupling lens315via the photonic crystal optical fiber, and then directed towards the first dichroscope322after reflection by the first reflector324. It passes through the second dichroscope323after reflection by the first dichroscope322, and finally reaches the objective lens33for processing the substrate sample material.

For the microscopic imaging optical path, red illumination light is transmitted via the optical fiber to the second optical fiber coupling lens3112and reflected by the third reflector3113towards the first beam splitter3114. Light separated by the first beam splitter3114passes through the first dichroscope322, the second dichroscope323, and the objective lens33successively, reaching the substrate sample material. After reflecting off the sample material, the light passes back through the objective lens33, the second dichroscope323, the first dichroscope322, and the first beam splitter3114, some of it passing through the eyepiece3115before reaching the CCD camera3132for imaging.

The reflectors within the optical path mechanism3are made of fused quartz and coated with dielectric films to increase laser reflectivity and reduce loss. The first dichroscope322utilizes a 500 nm dichroic long-pass filter to reflect the laser used for processing, while the second dichroscope323employs a 700 nm dichroic short-pass filter to transmit the laser used for processing and reflect the laser used for ultrafast imaging.

It's worth noting that due to the flexibility of optical fibers, the arrangement of optical paths can be conveniently achieved. The bulky and heavy external laser device is situated outside an adjusting mechanism6, ensuring the transmission of laser beams even when the adjusting mechanism6moves the optical path mechanism3.

Notably, the first beam splitter3314is an ultraviolet quartz broadband beam splitter with a model BSW05, featuring a 50:50 beam splitting ratio and a wavelength range of 400-700 nm. The eyepiece3115adopts a symmetric design, consisting of two identically structured double-glued lenses with a focal length of 135 mm, effectively correcting chromatic aberration and astigmatism to ensure that the observed surface image of the sample remains undistorted. The CCD camera3132is of model 1500M-CL-TE.

The ultrafast imaging optical path operates by emitting a laser from the external laser device to the sixth reflector3122, refracting it towards the grating3123. After passing through the grating3123, the laser is dispersed into different wavelengths, forming a high-speed time series in the time domain. Subsequently, the laser traverses the third planoconvex lens3124, the second beam splitter3116, the first planoconvex lens326, the second reflector325, and the second dichroscope323in sequence before focusing on the sample surface through the objective lens33. The laser reflected by the sample surface then follows a reverse path through the optical components before reaching the external ultrafast imaging system. This setup allows for imaging with ultrahigh temporal resolution, enabling the observation of sample changes over extremely short time periods.

By integrating the laser processing, microscopic imaging, and ultrafast imaging optical paths, the system simplifies optical path structures, reduces the number of devices required, and allows for modular interchangeability. Additionally, during sample processing, the surface of the sample can be imaged microscopically, facilitating observation of the laser's effects. The cylindrical design of the outer contour of the optical path mechanism3maximizes integration while occupying minimal space, meeting the mounting requirements of the confined MBE internal space.

In a preferred embodiment, the heat insulation mechanism4comprises a shield body41and heat-insulation light-transmission members42. The shield body41, cylindrical and internally hollow, is positioned on the side of the external optical path assembly31near the sample table2. It surrounds the external side of the internal optical path assembly32and the objective lens33, with a light transmission hole on the side facing the sample table2. Heat-insulation light-transmission members42are situated within the shield body41, concentrically aligned with the objective lens33and positioned away from the internal optical path assembly32.

The objective lens33, being closest to the surface of the sample table2, receives the largest area of heat radiation among all components in the optical path mechanism3. Therefore, in this embodiment, a shield body41is added to the outer sides of the objective lens33and the internal optical path assembly32to block a significant portion of the radiation. This helps reduce the amount of heat absorbed by the objective lens33and lowers its temperature.

The shield body41has a thickness of 2 mm and is made of alloy steel with a smooth surface. A gold film is applied to the outer surface of the shield body41to facilitate rapid heat conduction. The outer surface of the shield body41undergoes high-level polishing to minimize surface emissivity, and then the gold film is applied to further reduce emissivity and increase heat conductivity, which enhances heat conduction efficiency.

At least two heat-insulation light-transmission members42, made of quartz glass, are spaced apart within the shield body41along its axial direction. Quartz glass has a high melting point (>1000° C.) and can function normally under high-temperature vacuum conditions. The surface of the quartz glass is plated to further reduce heat radiation transmissivity, minimizing the amount of radiation reaching the lens on the objective lens33.

Preferably, two heat-insulation light-transmission members42are used to achieve effective heat insulation for the objective lens33. While increasing the number of heat-insulation light-transmission members42may further reduce the temperature of the objective lens surface, too many members can affect the design of the objective lens optical system and compromise laser quality, leading to increased laser loss during transmission.

Since the objective lens33remains within the MBE growth chamber1, heat radiation absorbed by its shield body41is conducted towards the external optical path assembly31. If heat conduction is slow, heat may accumulate over time, raising the temperature of internal optical devices and potentially causing damage.

In this embodiment, the cooling mechanism5comprises a sleeve member51and an internal support member52. The sleeve member51is fixed on the outer side of the external optical path assembly31, away from the internal optical path assembly32, by a flange. It features at least two symmetrically distributed liquid passage openings on its outer side. The internal support member52divides the sleeve member51's internal space into a first cavity510, serving as the cooling channel, and a second cavity520, which accommodates the external optical path assembly31. Heat exchange medium flows through the liquid passage openings and the first cavity510, carrying away heat conducted by the objective lens33.

The liquid passage openings connect to the liquid outlet and inlet ends of external cooling circulating equipment, allowing circulating liquid to flow into the first cavity510. This effectively removes heat, preventing heat accumulation and facilitating heat dissipation and temperature reduction.

Additionally, an adjusting mechanism6is included, fixed relative to the ground and spaced apart from the MBE growth chamber1. It features a movable portion capable of multidimensional movement. The sleeve member51is fixed to the center of the movable portion via a flange on the side away from the internal optical path assembly32. This adjusting mechanism6enables multidimensional adjustment of the optical path mechanism3connected to the sleeve member51, allowing the laser's position focused on the surface of the substrate sample material to be adjusted.

Specifically, the adjusting mechanism6in this embodiment is a six-degree-of-freedom motion platform, such as model H-850.G2A.

To ensure sealing between the optical path mechanism3and the MBE growth chamber1during movement driven by the adjusting mechanism6, a telescopic sleeving member7is employed. Positioned on the outer side of the sleeve member51and located within the MBE growth chamber1, the telescopic sleeving member7, typically a bellows, connects to both the sleeve member51and the opening of the MBE growth chamber1via flanges. This arrangement maintains movement sealing between the optical path mechanism3and the MBE growth chamber1, allowing the sleeve member51to move with the adjusting mechanism6while ensuring a sealed environment.

In this embodiment, the telescopic sleeving member7is specifically designed as a bellows due to its elasticity. This design allows the sleeve member51to move along with the adjusting mechanism6, enabling both horizontal and vertical movement of the optical path mechanism3within the second cavity520. The upper and lower ends of the telescopic sleeving member7are sealedly connected to the MBE growth chamber1and the sleeve member51respectively using flanges. This arrangement ensures proper sealing between the MBE growth chamber1and the optical path mechanism3while the adjusting mechanism6drives the optical path mechanism3to move.

To ensure sealing between the internal optical path assembly32and the external optical path assembly31, a sealing assembly8is further incorporated. The sealing assembly8is sealedly connected to the internal optical path assembly32and the external optical path assembly31at their respective side ends using flanges. Additionally, the sealing assembly8features a light transmission portion that facilitates the transmission of light from the side of the external optical path assembly31to the side of the internal optical path assembly32, accommodating a laser source. This setup allows the internal optical path assembly32to maintain a vacuum environment within the MBE growth chamber1through the sealing assembly8.

It's important to note that the sealing between the internal optical path assembly32and the MBE growth chamber1is achieved through the coordinated efforts of the sealing assembly8and the telescopic sleeving member7. This sealing mechanism enables the optical path mechanism3to execute laser processing in a high-vacuum environment. Furthermore, the light transmission part is constructed using quartz material light-transmission glass.

Once a model is designed, it undergoes necessary simulations to verify its compliance with requirements and to develop improvement solutions based on simulation results. In this design, the structural model requires insulation to address heat transfer issues. Temperature changes induce thermal stress within a structure, leading to deformation, while the design of the optical system and the objective involves ray tracing of geometric optics.

The present invention also provides a method for optimizing a laser processing system integrated with an MBE device, outlined in the following steps:Step 1: Establish a geometric model of the optical path mechanism and employ simulation software, such as COMSOL, to conduct a heat-transfer analog simulation on the model;Step 2: Analyze the analog simulation result, correlating the temperature of the objective lens33with received heat radiation;Step 3: Based on the analysis result, add a radiation prevention structure to the outer side of the objective in the geometric model of the optical path mechanism. Then, employ simulation software again to conduct a heat-transfer analog simulation on the model;Step 4: Analyze the analog simulation result to assess the impact of the radiation prevention structure on heat radiation. Assume heat conduction and dissipation occur in a heat conduction mode;Step 5: Based on the analysis result, add a water cooling mechanism to the geometric model of the optical path mechanism. Conduct an analog simulation for heat-transfer analog simulation of the geometric model under different flow rates;Step 6: Analyze the analog simulation result to verify the reliability of the assumption made in Step 4;Step 7: Perform a structural-thermal-optical (STOP) multi-physical field coupling simulation analysis on the optimized solution structure using COMSOL. Judge whether the optimized solution structure can operate normally under a vacuum high-temperature environment based on changes in the root-mean-square radius value of a plot diagram;Step 8: Obtain an optimized solution.

In Step 1, COMSOL is used as the simulation software. To simplify the simulation, the geometric model of the objective lens33and the optical path mechanism3is streamlined. Specifically, the internal optical path assembly32, external optical path assembly31, telescopic sleeving member7, and objective lens33structures are simplified. Only the second concave lens3311closest to the sample table2is retained in the objective lens33, referencing the structure inFIG.10.

It's worth noting that since this lens is closest to the high-temperature sample, where the temperature is highest, if the temperature of this lens remains below 50° C., the remaining lenses will undoubtedly operate within the normal operating temperature range.

Given that the high-temperature sample is in a vacuum environment with the objective lens33and the internal optical path assembly32, heat energy transfer occurs solely via heat radiation. Consequently, the objective lens33and the internal optical path assembly32are subjected to heat radiation from the high-temperature sample, resulting in temperature increases. Additionally, since these components are in contact with each other and with the external environment, heat energy transfer via conduction and convection occurs. In the simulation model, heat radiation from the high-temperature sample to the laser processing system structure is simulated using the surface-to-surface radiation module of COMSOL. Heat transfer within the sleeve member51and the external optical path assembly31, as well as heat transfer with air, is simulated using the heat transfer module. A convective heat conductivity coefficient with the external environment is set to 10 W/(m2K).

Referring toFIG.11, the temperature distribution diagram of the model on the leftmost side indicates that the highest temperature is concentrated in the objective lens portion, particularly on the upper surface of the first lens. This temperature, reaching 195.2° C., significantly exceeds the operating temperature of the lens. Without appropriate protective measures, the objective lens33cannot function properly and may even sustain damage. The radiation diagram on the rightmost side illustrates that the upper surface of the objective lens33, facing the sample surface directly, receives the most radiation. The maximum radiance received by the upper surface of the lens barrel is 46538.8 W/m2, while the maximum radiance received by the upper surface of the lens is 4366.8 W/m2. This difference is primarily due to the materials used; the lens barrel, made of alloy steel, is opaque and absorbs significant heat radiation, whereas the lens, made of ZF6 glass, is semi-transparent and possesses high surface transmittance in certain bands, potentially exceeding 99%.

In Step 3, the radiation prevention structure consists of a shield body41and a heat-insulation light-transmission member42, designed to block most of the radiation and reduce the radiance received by the objective lens, thus lowering its temperature.

Referring toFIG.12, the maximum temperature of the shield body41is observed on the upper surface of the quartz glass, reaching 327.0° C., while the maximum temperature of the objective lens33is on its upper surface at 83.1° C. Although the radiation prevention shield body significantly reduces the temperature of the objective lens, it remains slightly higher than its operating temperature. Additionally, one heat-insulation light-transmission member42is added to the shield body41, maintaining a thickness of 2 mm and positioned 0.5 mm from the first piece of heat-insulation light-transmission member42. Simulation results of this structure's heat radiation at vacuum high temperatures reveal that the maximum temperature of the upper layer of quartz glass is 358.7° C., the maximum temperature of the lower layer of quartz glass is 232.0° C., and the maximum temperature of the objective lens is 62.3° C. Although the maximum temperature of the objective lens still slightly exceeds its operating temperature, it's noticeably lower.

Step 3 further involves simulating the number of heat-insulation light-transmission members42to be installed and selecting the optimal number based on simulation data.

If the number of heat-insulation light-transmission members42is continually increased, the maximum temperature of the objective lens33will remain within its operating temperature range. However, excessive installation may impact the optical system design of the objective lens33, affect laser quality, and increase laser loss during transmission, ultimately affecting the laser system's processing and imaging capabilities. By limiting the heat radiation blocked by the shield body41, the accumulated heat in the objective lens33, the internal optical path assembly32, and the external optical path assembly31can be rapidly transmitted to the external environment through increased heat transmission, thereby reducing the objective lens33's structural temperature.

Common cooling methods in this embodiment include air cooling and water cooling, each with its advantages and disadvantages. Air cooling structures are simple to install and primarily enhance convective heat dissipation by blowing air to remove radiator heat. However, their effectiveness is inferior to water cooling. The cooling pipeline design favors water cooling heat dissipation, requiring circulating cooling water through a water cooling box to dissipate heat.

In Step 5, as depicted inFIG.13, analog simulations are conducted for temperature distributions of the laser processing system structure under three different cooling water flow rates (0.05 m/s, 0.08 m/s, and 0.10 m/s) with a cooling water temperature of 20° C. When the cooling water flow rate is 0.05 m/s, the maximum temperatures of the upper and lower layers of the heat-insulation light-transmission member42on the shield body41and the second concave lens3311of the objective lens33are 350.2° C., 223.9° C., and 42.3° C., respectively. Notably, the maximum temperature of the second concave lens3311remains below 50° C., ensuring the entire objective lens33stays within its normal operating temperature range.

Subsequently, an optimized solution is achieved, incorporating a shield body41and cooling mechanism5. The shield body41blocks a significant amount of heat radiation, while the cooling mechanism5facilitates the timely conduction of accumulated heat to the external environment. Thus, even in a vacuum high-temperature environment, the objective lens33maintains its normal operating temperature range.

When the cooling water flow rate is 0.08 m/s, the maximum temperatures of the upper and lower layers of the heat-insulation light-transmission member42on the shield body41and the second concave lens3311of the objective lens33are 349.1° C., 222.3° C., and 39.2° C., respectively. At a cooling water flow rate of 0.10 m/s, these temperatures further decrease to 348.7° C., 221.7° C., and 38.1° C., respectively. Clearly, higher cooling water flow rates result in lower structure temperatures. At all three cooling water flow rates, the most significant temperature reduction is observed in the objective lens, followed by the lower layer of the heat-insulation light-transmission member42on the shield body41, and then the upper layer of the heat-insulation light-transmission member42.

Additionally, since the MBE device requires internal baking for 2-3 days before powering up, maintaining an internal temperature of 300° C., even during this period when the objective lens33is inactive, its temperature must not be excessively high to prevent damage.

As illustrated inFIG.14, during sample baking, the MBE growth chamber1temperature reaches 300° C. Under these conditions, with a cooling water flow rate set to 0.20 m/s, the simulation model reaches a stable state. The maximum temperatures of the upper and lower layers of the heat-insulation light-transmission member42on the shield body41and the second concave lens3311of the objective lens33are 141.7° C., 138.0° C., and 46.2° C., respectively. Consequently, the temperature of the objective lens33remains within its normal operating range. The maximum temperature of the cooling water is 38.0° C. Based on the simulation result, the objective lens33maintains a temperature within its normal range when the MBE growth chamber1bakes the sample at 300° C.

It's important to note that while the shield body41and the objective lens33experience high temperatures in the laser processing system, the internal and external optical paths and the sleeve member51are farther from the high-temperature sample, receive less intense heat radiation, and are closer to the cooling channel. Consequently, these components effectively reduce their temperature through the water-cooling channel. Compared to the shield body41temperature, the temperatures of the internal and external optical path structures and the sleeve member51are significantly lower, resulting in minimal thermal stresses and displacements. Therefore, the structural-thermal-optical performance analysis primarily focuses on the shield body41and the objective lens33.

As depicted inFIG.15, the analysis process in Step 7 involves using solid mechanics, solid heat transfer, and geometric optics modules in COMSOL. To simplify the simulation process, surface-to-surface radiation is not directly used to simulate heat radiation when analyzing the structure thermally. Instead, temperature results from the heat radiation simulation in Step 5 are utilized as temperature conditions in solid heat transfer. Additionally, simulation results of the cooling water at a flow rate of 0.1 m/s are employed. Maximum temperatures at specific positions are as follows: 348.7° C. for the shield body41, 221.7° C. for the upper layer of the heat-insulation light-transmission member42, 38.1° C. for the lower layer of the heat-insulation light-transmission member42, 34.5° C. for the lens of the objective lens33, and 93.3° C. for the rear end face of the objective lens33, and for the rear end face of the shield body41. These simulations simplify the process without compromising accuracy. In the solid mechanics module, fixed constraints are applied to the rear end faces of the objective lens33and the shield body41, and the structure parts are unified. This setup is configured similarly in the geometric optics module for ray tracing simulations described above.

After establishing the geometric structure and setting boundary conditions using COMSOL, simulations are conducted on the objective lens33and the shield body41. Stress primarily accumulates in the connection between the shield body41and the heat-insulation light-transmission members42due to their disparate thermal expansion coefficients—the shield body, made of alloy steel, expands more than the light-transmission members. The maximum displacement occurs at the top of the shield body due to its higher thermal expansion coefficient, reaching 97.5 μm, while the displacement is smaller on the objective lens33due to its lower temperature. Temperature-induced thermal stresses alter the geometry of the structure and the position of the lens, impacting the optical system. The right figure illustrates the results of ray tracing based on temperature and structural fields. As shown inFIG.16, root-mean-square radius values of the plot diagram at wavelengths of 400 nm, 635 nm, and 800 nm are 4.06 μm, 6.59 μm, and 4.08 μm, respectively. In comparison, without temperature equalization, these values are 1.808 μm, 3.365 μm, and 2.548 μm, respectively. Despite increased values due to the coupling effect of temperature and structure, they remain within an acceptable range, ensuring normal operation of the objective under vacuum high-temperature conditions.

Operating Principle:

The optical path mechanism3is inserted into the MBE growth chamber1through its opening, where the telescopic sleeving member is affixed to the MBE growth chamber1via a flange in a sealed connection. This seals the MBE growth chamber1with the optical path mechanism3, leaving the internal optical path assembly32partially exposed to vacuum. The shield body41and heat-insulation light-transmission member42work together to reduce radiance received by the objective lens33and lower its temperature. Simultaneously, circulating liquid from external cooling equipment flows through the first cavity510, dissipating heat and preventing its accumulation.

These embodiments represent the invention's preferred embodiments and should not limit its scope. Any modifications, equivalent replacements, improvements, etc., made within the spirit and principles of the invention should be considered within the protection scope of the invention.