E-type electron gun electron beam evaporation coating machine coating optical components sna emiconductor optical components

E-type electron gun: The core evaporation source is composed of a cathode, a focusing electrode, and an accelerating anode. The electron beam presents a nearly circular spot and is equipped with a rapid scanning function. It can precisely bombshell coating materials and is suitable for the evaporation of various high-melting-point materials. It is also a key component that distinguishes it from other types of electron beam coating machines.

Vacuum system: It includes a vacuum chamber, a composite molecular pump, a mechanical pump, a gate valve, etc. The vacuum chamber often adopts a U-shaped box design, which can ensure a clean coating environment. The vacuuming system can achieve a vacuum degree of ≤6.67×10⁻⁵Pa (after baking degassing), reducing the interference of air on the purity of the film.

Evaporation and carrying components: Mostly water-cooled multi-cell crucibles (commonly designed with four or six cells), which prevent the crucible from melting itself and contaminating the coating material, and can hold multiple different materials simultaneously. When paired with a rotating substrate heating stage, the maximum substrate heating temperature can reach 800℃±1℃. It can also adjust the distance between the substrate and the evaporation source to ensure the uniformity of the film layer.

Measurement and control as well as electrical control system: Equipped with a quartz crystal oscillator film thickness controller, the film thickness display range is 0-99.9999 μm, and some can be optionally equipped with optical film thickness automatic control. The entire process of vacuum, baking, evaporation, etc. is automatically controlled through PLC and industrial control computer, and it also includes auxiliary control modules such as vacuum measurement and working gas path.

After the equipment is started, the pumping system first evacuates the vacuum chamber to a high vacuum state to reduce the scattering and contamination of the evaporated particles by gas molecules.

1. The cathode of the E-type electron gun is heated and emits electrons. These electrons are focused by the focusing electrode and accelerated at the anode to form a high-energy electron beam, which precisely bombards the coating material inside the crucible with the assistance of a magnetic field.
2. After absorbing the high energy of the electron beam, the material rapidly heats up to the evaporation or sublimation temperature, forming gaseous particles.
3. Gaseous particles move upward towards the substrate in a vacuum environment. Due to the small resistance to particle movement under vacuum, they can be uniformly condensed on the substrate surface.
4. During the coating process, the film thickness controller monitors the film layer thickness in real time, and the electrical control system adjusts parameters such as the electron beam power to ensure that the film layer thickness meets the preset requirements. After the coating is completed, the crucible can be switched to achieve multi-layer film deposition without destroying the vacuum environment.

During the coating process, the film thickness controller monitors the film layer thickness in real time, and the electrical control system adjusts parameters such as the electron beam power to ensure that the film layer thickness meets the preset requirements. After the coating is completed, the crucible can be switched to achieve multi-layer film deposition without destroying the vacuum environment.

• Concentrated and controllable energy: The electron beam has a high energy density and can directly act on materials. Combined with a rapid scanning function, it can not only evaporate materials with melting points over 3000℃ such as tungsten and molybdenum, but also prevent local overheating and damage to low thermal conductivity materials. Moreover, the evaporation rate can be controlled by adjusting the electron beam current.
• Strong film layer adaptability: It supports single-source, dual-source or triple-source evaporation. By placing different materials in adjacent crucibles, various types of films such as alloy films and composite films can be prepared, and the refractive index stability of the film layer is high (δn≤0.005).
• It combines professionalism and flexibility: It is suitable for small-batch experiments in university research and can also meet the requirements of industrial-grade small-batch production such as 6-inch wafers. It can be operated manually or semi-automatically. Some models support program control to meet the needs of different scenarios.

The purity and quality of the film layer are high: The vacuum environment combined with water-cooled crucibles reduces contamination, and the purity of the film layer can reach 99.99% (4N grade). Moreover, the density of the film layer is 30% higher than that of the ordinary evaporation method, with strong adhesion and excellent anti-deliquescence performance.

Good evaporation efficiency and repeatability: The deposition rate range is wide (0.1μm/min - 100μm/min), capable of both thin layer preparation and thick film deposition. The process repeatability of the coating process is high (CPK≥1.67), and a consistent film layer can be stably produced under the same parameters.

High material utilization rate: Compared with technologies such as magnetron sputtering, electron beam evaporation has a higher material utilization rate, reducing material loss. Meanwhile, multi-cell crucibles can avoid frequent material replacement, thereby enhancing the coating efficiency.

In the field of optics, it is the core equipment for coating optical components such as laser lenses, spectacle lenses, and architectural glass. It can prepare optical films such as SiO₂ and TiO₂, enhancing the light transmission, reflection or filtering performance of the components.

In the field of semiconductors and electronics: It is used for the preparation of thin films for semiconductor optical components, MEMS devices, photodiodes, etc., as well as the production of conductive glass and semiconductor thin films, and is compatible with industrial-grade processes such as 6-inch wafers.

In the field of new energy and sensing: Anti-reflection films for photovoltaic devices and functional films for precision sensors (such as metal oxide sensors, ultraviolet/infrared sensors) are prepared to ensure the photoelectric conversion efficiency and detection sensitivity of the devices.

In the fields of scientific research and teaching: It has become an important device for colleges and universities as well as research institutions to study ferroelectric thin films, piezoelectric materials, etc. It can carry out preparation experiments of single-layer films, multi-layer films and doped films, and assist in the research and development of new materials.