A cryopump is a type of vacuum pump that uses extremely low temperatures to capture and remove gas molecules from a vacuum chamber. By cooling surfaces to cryogenic temperatures, typically below -150°C, gases like nitrogen and oxygen condense and freeze onto these surfaces, effectively creating a vacuum. Cryopumps are commonly used in various applications, including semiconductor manufacturing and particle accelerators. They are efficient and can achieve very low pressures, making them ideal for environments where high vacuum levels are necessary for processes like thin film deposition or surface analysis.