Process simulation is the conversion of multiple two-dimensional layout geometries and process information into a three dimensional representation of the output shape. It is used to provide feedback in the design/fabrication loop before the full commitment to build a prototype is made. In the present state of MEMS technology it is used to reduce the number of trial and error physical fabrication iterations required to converge on the final design, masks and processes. In the future, it will also be used to guide the development of improved processes and to assess the sensitivity of the design to normal process variations. It can also play a role in developing design rules.

• Finding: While a "clean separation" between design and fabrication is one ideal, the current state of MEMS developments will greatly benefit from accurate, efficient simulation of fabrication processes. The primary benefit will be a reduction in the number of prototype cycles required.
• Recommendation: Evaluate process simulators currently available (both for VLSI and MEMS) and support research efforts to advance the state of fabrication process simulation, including continuous-time simulations, process variations, second- and third-order fabrication effects, and performance metrics.
• Finding: Process simulation supports fabricators in building a science underlying their empirical results and it supports designers working on new processes who are seldom able to use detailed formulations for specific regions of design space.
• Recommendation: Support the basic science underlying the simulation of classes of processes rather than the definition of detailed empirical relations in any narrow process region. Support process simulation capability and process sensitivity studies for the industry standard processes where there can be rapid prototyping to move the technology ahead.