There is provided a system including a monitoring unit that analyzes, using a sensor, components of a first gas which may include first components and a pre-separation unit disposed upstream of the monitoring unit. The pre-separation unit includes: a first supply line that supplies the first gas to the monitoring unit; a second supply line that supplies a second gas, which includes components obtained by removing the first components from the first gas using a first separator, to the monitoring unit; and an automatic valve station that periodically switches between the first supply line and the second supply line to alternately supply the first gas and the second gas to the monitoring unit.

There is provided a system including a monitoring unit that analyzes, using a sensor, components of a first gas which may include first components and a pre-separation unit disposed upstream of the monitoring unit. The pre-separation unit includes: a first supply line that supplies the first gas to the monitoring unit; a second supply line that supplies a second gas, which includes components obtained by removing the first components from the first gas using a first separator, to the monitoring unit; and an automatic valve station that periodically switches between the first supply line and the second supply line to alternately supply the first gas and the second gas to the monitoring unit.

A substrate drying method for drying a front surface of a substrate having a pattern includes a sublimation-agent-liquid-film placing step of placing a liquid film of a liquid sublimation-agent on the front surface of the substrate, a high vapor-pressure liquid placing step of placing a liquid film of a high vapor-pressure liquid that has vapor pressure higher than the sublimation agent and that does not include water on the liquid film of the sublimation-agent placed on the front surface of the substrate, a vaporizing/cooling step of losing vaporization heat in response to vaporization of the high vapor-pressure liquid, and, cooling the sublimation-agent, and, as a result, solidifying the liquid film of the sublimation-agent, and, forming a sublimation-agent film on the front surface of the substrate, and a sublimating step of sublimating the sublimation-agent film.

A substrate drying method for drying a front surface of a substrate having a pattern includes a sublimation-agent-liquid-film placing step of placing a liquid film of a liquid sublimation-agent on the front surface of the substrate, a high vapor-pressure liquid placing step of placing a liquid film of a high vapor-pressure liquid that has vapor pressure higher than the sublimation agent and that does not include water on the liquid film of the sublimation-agent placed on the front surface of the substrate, a vaporizing/cooling step of losing vaporization heat in response to vaporization of the high vapor-pressure liquid, and, cooling the sublimation-agent, and, as a result, solidifying the liquid film of the sublimation-agent, and, forming a sublimation-agent film on the front surface of the substrate, and a sublimating step of sublimating the sublimation-agent film.