Lithium Coating to Remove Impurities in Vacuum Systems

Web Published:

Princeton Docket # 18-3401


Removing water and impurities from the walls of the chamber of is an important consideration in sensitive high vacuum systems. Researchers at the Princeton Plasma Physics Lab have invented a new process to quickly release lithium vapor into these systems, using a porous stainless steel tube containing liquid lithium and a heating element. Designed to control impurities in fusion reactors, this invention also has immediate application in chemical and physical vapor deposition industries.


Traditionally, these industries use getter materials such as titanium to remove impurities, which results in coatings on chamber walls that are hard to remove. By using a liquid lithium process, lithium coating can be applied onto the vacuum vessel wall uniformly in all directions in a very timely and efficient way. As an alkali metal, lithium is more reactive and tends to pump impurities such as water, oxygen, nitrogen, etc. more efficiently. It is also easier to clean the lithium compound coating off the vacuum vessel walls after use. 



•       Chemical vapor deposition

•       Physical vapor deposition

•       Semiconductor industry

•       High vacuum systems



•       Easy to remove lithium from vacuum chamber

•       High heating efficiency

•       No dripping from device

•       Uniform coating


Stage of Development

A prototype device has been created and loaded with lithium in an argon glove box. Tests show 100% filling and no liquid lithium dripping at 500ᵒC.


Intellectual Property & Development Status

Patent protection is pending.

Princeton is currently seeking commercial partners for the further development and commercialization of this opportunity.



Chris Wright

Princeton University Office of Technology Licensing • (609) 258-6762  •



Dang Cai is a responsible engineer at Princeton Plasma Physics Lab. He obtained his Ph.D in Mechanical Engineering from Stony Brook University in 2006. He has been working as an engineer since 2007.


Princeton Plasma Physics Laboratory         

Princeton Plasma Physics Laboratory (PPPL) is a United States Department of Energy National Laboratory managed by Princeton University. PPPL is collaborative national center for fusion energy research. The Laboratory advances the coupled fields of fusion energy and plasma physics research, and, with collaborators, is developing the scientific understanding and key innovations needed to realize fusion as an energy source for the world. An associated mission is providing the highest quality of scientific education.


Patent Information:
For Information, Contact:
Chris Wright
Licensing Associate
Princeton University
Dang Cai
Robert Kaita
Richard Majeski