Measurement apparatus and measurement method

A measurement apparatus, comprising:

• a measurement unit that includes one or more semiconductor sensors each including an adsorption layer formed of metal oxide, a measurement chamber that houses the semiconductor sensor, and a heating unit that heats the semiconductor sensor to a first temperature, a second temperature, or a third temperature, the second temperature and the third temperature being higher than the first temperature;
• a gas supply unit that includes a first gas supply line and a second gas supply line, the first gas supply line supplying a first gas that does not contain a reducing gas to be detected to the measurement chamber, the second gas supply line supplying a second gas that contains the reducing gas to the measurement chamber;
• and
• a control unit that controls the measurement unit and the gas supply unit,
• the control unit being capable of executing
• refresh treatment for cleaning the adsorption layer while heating the semiconductor sensor to the third temperature in an atmosphere of the first gas,
• low-temperature measurement treatment for measuring a resistance value of the semiconductor sensor while heating the semiconductor sensor to the first temperature in an atmosphere of the second gas, and
• high-temperature measurement treatment for measuring the resistance value of the semiconductor sensor while heating the semiconductor sensor to the second temperature in the atmosphere of the second gas,
• the control unit executing the low-temperature measurement treatment as a process following the refresh treatment.