cryopump

A cryopump is a type of vacuum pump that operates by freezing and adsorbing gases onto extremely cold surfaces. This process removes gases from a system, creating a vacuum. Cryopumps can achieve very high pumping speeds across a wide range of pressures, from 10^-3 torr down to below 10^-10 torr. They typically use helium to achieve the necessary low temperatures, around 15 K for gaseous helium or 4.2 K for liquid helium. However, cryopumps are less effective at pumping gases like helium and hydrogen, which have high vapor pressures even at these low temperatures. Therefore, they are often used in conjunction with other pumps, such as diffusion or sputter ion pumps, to create a complete vacuum system. These pumps are commonly employed in applications like space simulation chambers.12