In the helium mass spectrometry leak detection technology, the multi-port composite molecular pump can meet different leak detection requirements by connecting to different air extraction ports, which broadens the application scope of traditional molecular pump. The location of the gas extraction port affects the pumping capacity of the molecular pump, which determines the performance of the leak detector. Based on the basic theory of molecular pump pumping, the calculation model of multi-port compound molecular pump is established. The pumping ports of medium check valve are set at different positions in the drag stage of molecular pump. The pumping characteristics are studied by combining with the actual use of mass spectrometer, and the influence of medium check position on helium leakage is analyzed. The optimal opening position under different leak detection conditions is obtained, which provides a theoretical basis for the structural optimization design of multi port composite molecular pump for leak detection. The results show that, when the medium detection port is set at the height between 15mm and 20mm, it can not only obtain better detection performance, but also ensure the allowable pressure of mass spectrometry chamber, and has a wide working pressure range.

The TVS-2M high burnup nuclear fuel rods should be dried at high temperature and then vacuum helium leak detection should be conducted. The original technology requires anodic oxidation process, which has disadvantages of high cost and high transportation risk. Therefore, the feasibility of removing the anodic oxidation process is explored. The effect of canceling anode oxidation and the feasibility of helium leak detection at high temperature were analyzed. The design scheme of drying and leak detection equipment was determined, and the process flow was formulated. The system detection feasibility and simulation experiment were verified. The results show that the new high temperature helium leak detection equipment with heating and leak detection functions can meet the tightness test of the TVS-2M fuel rod without affecting the quality of fuel rod. It is verified that the helium leakage detection output value of TVS-2M fuel rod can be kept true and reliable without anodic oxidation, reflecting whether there is leakage point.

Atomic layer deposition(ALD) technology is a thin film growth technology based on self-limiting interfacial reaction. The atomic layer technology can prepare thin films with dense structure, high conformal, low defect density, excellent performance and great uniformity. Alumina is the most common thin film deposited by atomic layer deposition（ALD-Al₂O₃）. Al₂O₃ film has high transparency, high band gap width, high dielectric constant, and high barrier properties as well as good chemical and thermal stability. As a passivation layer, gas permeation barrier layer and grid dielectric layer, alumina is widely used in solar cell passivation layer, OLED packaging, organic solar cell dielectric layer, printed electronics and microelectronic device encapsulation. This article reviews the principle, online diagnosis and application development status of ALD-Al₂O₃, including the growth mechanism, monomer selection, deposition method, and in-situ diagnosis of alumina film. The application and the future development trend of ALD-Al₂O₃ film are predicted.

The metallization coating of the hemispherical resonator is an important process in the development of the hemispherical resonator gyroscope. For the requirement of maintaining a high Q value after the metallization of the hemispherical resonator, the high-precision preparation of nano metal films is required. In this paper, nano aluminum films were prepared on quartz glass substrates by DC magnetron sputtering with high purity Al as target material and high purity Ar as sputtering gas. The thickness, surface roughness and surface morphology of the films deposited under different sputtering power and chamber pressure were measured and characterized. The effects of process parameters on deposition rate, surface roughness and micro morphology of the Al films were discussed. The results show that the deposition rate of Al films increases with the increase of sputtering power. With the increase of chamber pressure, the deposition rate shows a trend of first increasing and then decreasing. With the increase of sputtering power, the grain size of the films increases, and with the increase of the chamber pressure, the particle diameter of the film increases first and then decreases. The as-coated film was the most uniform and compact under the condition of 100W sputtering power and 1.6Pa chamber pressure. The above conclusions have important guiding significance for the high-quality preparation of hemispherical harmonic oscillator curved nano films.

When glassy carbons crucible and electron beam evaporation equipment are used for coating, with the consumption of gold material, more particles on the surface of gold film are obtained at the same deposition rate, which seriously affects the flatness and local uniformity of the film. In this work, the phenomenon was explained by the theory that the corona discharge of spherical droplet on the crucible wall caused by thermally electron emission from liquid metal surface led to material splashing.At the same deposition rate, two kinds of gold films were obtained by changing the volume proportion of gold materials in the crucible, and their surface morphology and infrared spectral transmission properties were compared and analyzed. The results showed that when the material volume accounted for about 26% of the crucible volume, there were many black particles on the gold film surface, which were approximately spherical or ellipsoidal in shape, and the main component is still gold. When the material volume accounted for about 26% of the crucible volume,there were no black particles on the gold film surface, and the infrared spectral transmittance is 5% lower than the former.

The barrel is made of composite materials and metal flexible components. The cylinder can not directly contact with the working medium, and thus a protective film needs to be deposited onto the inner wall. In this paper, through the screening of different material pretreatment processes of the cylinder, the magnetron sputtering process is used for process research and trial production. Finally, the integrated coating process route is determined and the corresponding process parameters are developed. The process parameters were used to realize one-time coating on the inner wall of the cylinder successfully. The as-prepared film is complete and has a certain binding force and film thickness.

In this paper, based on the structured film system and using the film system software to optimize the design, a multilayer medium film system is designed to meet the requirements of wide angle incidence near ultraviolet reflector used in the UV system of the projection photolithography machine. Based on the planet-type rotating mechanism, the film thickness distribution within 400mm in the diameter of the plane near-ultraviolet reflector was calculated. Through the research on the film thickness uniformity correction technology, the spectral curve deviation of the film thickness on the lens surface was realized to be less than 5nm.

Multilayer films with different structures(TiW/Ni/Au & Ti/Ni/Au) and thicknesses were deposited on ceramic substrates (96Al₂O₃) by magnetron sputtering. The gold film thickness was controlled by adjusting the sputtering time. The multilayer films were used to simulate the gold wire bonding in optical communication modules, and their bonding performance were evaluated. The results show that Ti/Ni/Au structure has better bonded effect than that of the TiW/Ni/Au. In the experiment of gold wire bonding with different thickness, the magnitude of pull and thrust strength changes with the increase of gold layer thickness. The pull strength is kept in 7.5gf±3% when the thickness is less than 2μm(1gf=9.81× 10^-3N）. When the thickness of the gold film is 930 nm, the thrust strength is the maximum(78.68gf), and it decreases with the increase of the thickness. Then, the thrust strength is kept in 72.03gf±1.8%. The results of statistical analysis show that the dispersion degree of push and thrust strength decreases first and then increases with the increase of thickness. Therefore, there is a certain relationship between the bonding properties and the structure and thickness of the bonding film layer. The results show that the thickness is too thin to bond with the gold wire, while the thicker film reduces the matching with the bonding process. This indicates that the bonding quality can be controlled and the cost can be saved by reducing the thickness of the gold layer.

During arc ion plating process, the macroparticle defects are focused in recent years. The relationship between Ti macroparticle size, velocity and energy change in the spatial transmission was calculated, which was used to account for the main change reasons of the macroparticle morphology in the coatings surface. During the transmission process, the density of ions and electrons changed at different working distances. The Ti macroparticles were affected by the collisions of ions and electrons, which caused the velocity and energy changes of Ti macroparticles. The Ti macroparticles remained semi-solid and liquid when reaching the substrate surface. The morphologies of Ti macroparticles showed flat oval and strip after the collision with the substrate surface.

In order to simulate the monitoring environment of the concentration of carbon dioxide in the atmosphere, a U-shaped gas pool with large diameter and long pipeline was designed, which can control the temperature of the gas pool at 20~40℃, the temperature control accuracy can reach ±0.5℃, and the pressure control accuracy is 2mbar. This article briefly describes the overall design of the system, and conducts temperature and pressure stability tests to verify the structure. The test results show that it has high-precision temperature control capability without forced cooling background, and the temperature control accuracy is better than ±0.5℃. At the same time, the vacuum degree is accurately controlled according to the pressure feedback closed loop, and the control accuracy meets the test requirements.

In this paper, the background of isolation valve for vacuum induction furnace is elaborated briefly. The function in varied situations is thoroughly probed. Then the structure and feature of several different kinds of isolation valves used worldside are described. At last, the developing direction of the structure and function of isolation valve in the future is prospected.

In this paper, the starting temperature of various reactions in vacuum carbothermal reduction of titanium oxide is discussed from the point of thermodynamics. The results of thermodynamic calculation show that the order of carbothermal reduction of titanium ore and ilmenite in vacuum is TiO₂→Ti₃O₅→Ti₂O₃→TiO→Fi and FeTiO₃→TiO₂→Ti₃O₅→Ti₂O₃→TiO→Ti. The different content ratio of TiO₂ and C results in different substances when TiO₂ and C occurs the carbothermal reduction reaction. It produces Ti₂O₃ when the molar ratio of TiO₂ to C is 2∶1. It produces Ti₃O₅ when the molar ratio of TiO₂ to C is 3∶1. It produces TiO when the molar ratio of TiO₂ to C is 1∶1. It produces Ti when the molar ratio of TiO₂ to C is 1∶2. It produces TiC when the molar ratio of TiO₂ to C is 1∶3.

The crucible for vacuum electron beam melting works in high vacuum and high temperature environment, and needs to be cooled sufficiently to ensure its normal operation. The closed cycle water supply device for crucible cooling is non-nuclear safety seismic category equipment with special requirements. It must be ensured that the device is undamaged and can supply water normally under earthquake conditions. Therefore, it is great useful to do anti-seismic analysis. The frame of equipment is the most important part in anti-seismic analysis. Based on ANSYS, the modal of frame was calculated, the seismic performance was analyzed with response spectrum analysis method. The safety capability of the frame under earthquake load is evaluated, which provides a reference for anti-seismic design and seismic experiment of the device. The research results have important reference for production practice.

Currently, countries around the world are actively responding to the impact of the COVID-19 epidemic. The development and production of COVID-19 vaccines have become the focus of research institutes and medical enterprises. Compared with liquid vaccines, lyophilized vaccines can be transported and stored easily, which provides a feasible solution to solve the problem of cold chain transportation of vaccines. Vacuum freeze-drying technology is a key link in the production of lyophilized vaccines, which plays a vital role in the safety and efficacy of vaccines. In this paper, the basic principle of freeze-drying and the main structure of the freeze dryer are introduced firstly. Then, the freeze-drying process of vaccine and the advantages and disadvantages of freeze-drying vaccine are described. Furthermore, the main factors affecting the quality of freeze-drying vaccine(including the selection of protective agent and the design of freeze-drying parameters) are also discussed. The authors hope that this article may contribute to the development and production of COVID-19 vaccines.

In order to improve the freeze-drying efficiency and quality of kiwifruit slices, the effect of slice thickness, pre-freezing method and drying time on the drying rate and quality of kiwifruit slices during freeze-drying process was studied by single factor experiment. The interaction between various factors was analyzed and the regression model of the drying rate of kiwifruit slices is obtained by the response surface method. The results show that the influencing order on the drying rate is drying time, slice thickness, and pre-freezing method. Among them, there was significant interaction between slice thickness and drying time, while there was no significant interaction between slice thickness and freezing mode, freezing mode and drying time. When the traditional single side drying method is used in the experimental freeze-drying equipment, the freeze-drying process of kiwifruit slices is as follows: slice thickness of 5mm, pre-freezing at -20℃, drying for 10h. After the optimization of double-sided drying, the slice thickness can be increased to 7mm, and the drying efficiency can be increased by about 11% at most.