A method and system for integrated circuit fabrication is disclosed. In an example, the method includes determining a first process parameter of a wafer and a second process parameter of the wafer, the first process parameter and the second process parameter corresponding to different wafer characteristics; determining a variation of a device parameter of the wafer based on the first process parameter and the second process parameter; constructing a model for the device parameter as a function of the first process parameter and the second process parameter based on the determined variation of the device parameter of the wafer; and performing a fabrication process based on the model.