(October 12, 2026) New progress has been made in the field of high-vacuum supporting materials in China. The new generation of high-purity vacuum diffuser oils have passed multiple batches of on-site tests by customers. These oils have been continuously improved in terms of extreme vacuum levels, low oil return rates, and thermal stability. This has further promoted the localization of core high-vacuum components, helping industries such as semiconductors, optical coating, vacuum metallurgy, and precision scientific instruments to reduce costs and increase efficiency.

Vacuum diffuser oils are the essential working media of oil diffusers. They achieve high-vacuum conditions through the principle of steam jets and are indispensable basic materials for various high-vacuum devices. The mainstream products in this industry include mineral-based diffuser oils and synthetic silicone-based diffuser oils (Series 704 and 705). Among them, benzene-based silicone diffuser oils are preferred for use in high-end applications such as semiconductor manufacturing, aerospace simulation chambers, electron microscopes, and mass spectrometers due to their extremely low saturated vapor pressure, excellent oxidation resistance, and low gas emission rates. In conventional industrial applications such as vacuum coating and vacuum melting, mineral-based diffuser oils remain in demand because of their cost-effective nature.

According to industry research data, with the expansion of N-type coating production in the photovoltaic sector and the acceleration of the localization of semiconductor equipment in China, the market for high-vacuum diffuser oils has seen steady growth. Previously, high-purity diffuser oils were mainly supplied by foreign manufacturers. In recent years, Chinese material companies have achieved breakthroughs in key processes such as molecular directed synthesis, advanced purification, and control of metal impurities. As a result, domestic diffuser oils have become qualified suppliers for domestic vacuum equipment manufacturers, wafer factories, and optical coating enterprises, enabling them to replace imported materials and breaking the long-term monopoly on imported materials.

The new generation of diffuser oils developed this time focus on two main areas of improvement: first, strict control of metal ion impurities to reduce the risk of gas emissions and chamber contamination, making them suitable for the highly clean semiconductor thin-film processes; second, enhancing the thermal oxidation stability of the oils, prolonging their service life, reducing the frequency of equipment downtime for oil replacement, and lowering operational costs. Test results show that these silicone-based diffuser oils can achieve extreme vacuum levels between 10⁻⁷ and 10⁻¹⁰ Torr, have controllable oil return rates, and are not prone to cracking under continuous high-temperature conditions, thus being suitable for long-term uninterrupted production operations.

Technical experts in the vacuum industry say that the selection of diffuser oils directly affects the stability of vacuum systems and the yield of finished products. Different application scenarios have different requirements for oil quality: general coating and vacuum metallurgy can use standard diffuser oils; however, for front-end semiconductor processing, space simulation, and high-end analytical instruments, ultra-high-purity benzene-based silicone diffuser oils are required, with very strict requirements for impurity levels and oil return control.

On the market level, there are two trends: on one hand, downstream customers now pay more attention to the total cost of ownership over the entire lifecycle of materials. They no longer simply compare purchase prices; instead, the lifespan of the oils, maintenance costs, and supply stability become key considerations. On the other hand, due to green manufacturing and chemical compliance requirements, environmentally friendly vacuum fluids that have low volatility, low toxicity, and are recyclable are becoming a focus of research and development. Both domestic and foreign manufacturers are developing new generations of low-VOC products.

Industry professionals believe that as high-end manufacturing in China continues to develop, the demand for high-vacuum industry supporting materials will continue to grow. As one of the “critical” materials in vacuum equipment, companies need to continue improving purity, batch stability, and overseas compliance certifications, and continuously refine their product portfolio, thereby providing supporting materials for domestic vacuum equipment to be used abroad. At the same time, companies also need to implement effective recycling and regeneration solutions for oils, aligning with the green and low-carbon development goals of the industrial sector.