(September 7, 2026) With the continuous expansion of domestic semiconductor, photovoltaic thin-film, and optical coating industries, the market for vacuum diffusion pump oils—which serve as the essential components in high-vacuum systems—is experiencing structural growth. Domestic products have made significant improvements in terms of purity, thermal stability, and low oil return, thereby facilitating their integration into high-end manufacturing supply chains.

Vacuum diffusion pump oils are crucial materials that enable oil diffusers to operate in high-vacuum environments. They are widely used in semiconductor PVD coating processes, heterojunction photovoltaic cell deposition, optical lens coating, electron beam melting, and scientific research facilities. The performance of these oils directly affects the ultimate vacuum level of the chamber, the efficiency of air removal, and the product yield. Key characteristics such as extremely low saturated vapor pressure, resistance to cracking at high temperatures, and low oil contamination are essential criteria for high-end products. For a long time, domestic high-ultra-vacuum applications relied primarily on foreign brands. However, with the advancement of silicone synthesis and molecular distillation techniques, local companies have gradually overcome their technical shortcomings. Several silicon-based diffusion pump oils have passed long-term performance tests by equipment manufacturers and can compete with international standards, making them suitable for various diffusion pump devices both domestically and internationally.

From a market perspective, the domestic vacuum diffusion pump oil sector continued to grow steadily in 2026. Expansion in semiconductor wafer production, the construction of N-type photovoltaic lines, and investment in scientific research vacuum equipment were the main drivers of this growth. Industry surveys show that downstream customers’ purchasing decisions have changed; they now focus more on the consistency of oil batches, its lifespan at high temperatures, maintenance requirements, and overall cost. The market share of high-purity synthetic diffusion pump oils is increasing, while the growth rate of traditional mineral-based diffusion pump oils is slowing down, leading to a trend of replacement of existing products.

In terms of competitive landscape, leading companies are investing heavily in research and development, conducting product certification and equipment compatibility tests. More and more domestic diffusion pump oils have become qualified suppliers for semiconductor equipment and leading photovoltaic companies. At the same time, the industry is developing in a hierarchical manner: top companies focus on high-end semiconductor and aerospace research fields, while smaller manufacturers concentrate on general vacuum applications such as industrial coating and heat treatment. By offering customized services and rapid delivery, they try to gain market share, but a monopolistic situation has not yet emerged.

Industry experts say that domestic diffusion pump oils have achieved initial success in mid-to-high-end applications. However, for some highly stringent ultra-high-vacuum scenarios, further accumulation of long-term operating data is still needed. In the future, as domestic high-end equipment becomes more widespread, along with the continuous improvement of environmental and safety regulations, diffusion pump oils with high purity, long lifespan, and complete compliance credentials will have greater market potential. The level of self-sufficiency in the domestic vacuum materials industry will also increase.