Due to the advances in device miniaturization it is often necessary to get a better understanding of the physical fabrication processes by applying advanced physical models. Since existing process modeling programs can handle only specific physical quantities, we have developed general purpose solvers for one and two space dimensions which are able to treat an arbitrary number of coupled partial differential equations for physical quantities. In the paper we will show the general formulation of the equations which can be solved. We deal with the user-interface of the programs and the numerical problems one has to face. To demonstrate the capabilities of the programs we will show typical applications.