A diagnostic device for diagnosing a state of a semiconductor manufacturing apparatus including a processing chamber in which a sample is processed, a transfer unit that is connected to the processing chamber and transfers the sample to the processing chamber, a valve that is disposed between the processing chamber and the transfer unit, an exhaust unit connected to the processing chamber via an exhaust pipe for exhausting the processing chamber, a first pressure gauge connected to the exhaust pipe and configured to measure a first pressure value of the exhaust pipe, and a second pressure gauge connected to the transfer unit and configured to measure a second pressure value of the transfer unit, the diagnostic device comprising:
- an external interface circuit connected to the semiconductor manufacturing apparatus via a network;
- and
- a processor configured to
- receive the first pressure value and the second pressure value from the semiconductor manufacturing apparatus via the external interface at a first time;
- receive the first pressure value and the second pressure value from the semiconductor manufacturing apparatus again via the external interface at a second time which is later than the first time by a predetermined period after the valve is opened;
- and
- determine wherein whether or not there is an anomaly in the exhaust unit or the exhaust pipe regarding the exhaust unit on the basis of the first pressure value at the second time regarding the exhaust unit during the predetermined period after the valve is opened.