Cryopump, cryopump system, and cryopump regeneration method

A cryopump comprising:

• a cryopanel;
• an adsorption area provided on the cryopanel and capable of adsorbing a non-condensable gas, the adsorption area including a non-combustible adsorbent containing silica gel as a main component thereof;
• a cryopump housing in which the cryopanel having the adsorption area is disposed in an interior thereof;
• a pressure sensor that generates a pressure measurement signal indicating an internal pressure of the cryopump housing;
• a rough valve mounted to the cryopump housing and connecting the cryopump housing to a rough pump;
• a memory that stores a first threshold value of pressure rise rate being a positive value and a second threshold value of pressure rise rate being a negative value;
• being smaller than the first threshold value;
• and
• a regeneration controller configured to:
• open the rough valve for a certain opening period in regeneration of the cryopump, wherein the rough valve remains continuously open throughout the certain opening period,
• receive a first pressure measurement signal from the pressure sensor measured during the certain opening period of the rough valve,
• compare a first pressure rise rate of the cryopump housing with the first threshold value based on the first pressure measurement signal,
• receive a second pressure measurement signal from the pressure sensor after it is determined that the first pressure rise rate is larger than the first threshold value based on the comparison, wherein the second pressure measurement signal is measured during the certain opening period of the rough valve,
• compare a second pressure rise rate of the cryopump housing with the second threshold value based on the second pressure measurement signal, and
• close the rough valve when the second pressure rise rate is smaller than the second threshold value.