A process control method used in a production process of a semiconductor device, comprising the steps of:
- performing a process over a substrate;
- measuring an in-plane distribution over the substrate;
- calculating a model formula of the in-plane distribution from measurement data obtained by measurement;
- comparing the measurement data with the model formula to calculate a set of parameters of the model formula;
- storing the parameters as data of the in-plane distribution over the substrate;
- comparing the measurement data with the model formula to detect measurement data which is inconsistent with the model formula;
- performing remeasurement for the inconsistent measurement data to update the inconsistent measurement data;
- and
- determining an abnormality in a semiconductor device production apparatus from a variation in the stored parameters,
- wherein the measurement data includes measurement coordinates over the substrate, and
- the model formula is obtained by modeling the tendency that the in-plane distribution concentrically varies and the tendency that the in-plane distribution varies along a diameter direction and along a tilt of the substrate.