We have enhanced the process simulator CODEF (1996) into a tool called CARAMEL (Contamination And Reliability Analysis of MicroElectromechanical Layout) for analyzing the impact of contamination particles on the geometrical and material properties of microelectromechanical systems (MEMS). CARAMEL accepts as input a microelectromechanical layout, a particulate description, and a process recipe. CARAMEL produces a mesh description of the defective layout that is completely compatible with the electromechanical simulator ABAQUS (1995). Analysis of CARAMEL's output indicates that a wide range of defective structures are possible due to the presence of contaminations. Moreover, electromechanical simulations of CARAMEL's mesh representations of defective layout has revealed that a wide variety of faulty behaviors are associated with these defects. In this paper, we describe CARAMEL and its application to the development of realistic fault models for MEMS.

The chip database (CDB) and the hierarchical chip database (HCDB) and their uses in a wafer representation server are described. The server provides data types and methods for hierarchically representing the three-dimensional geometry and fields of a semiconductor wafer during process, device, and yield simulation. The basic database data types and the general attribute mechanism have been used to create database extensions. These extensions implement operations frequently used by process and device simulation models. The combination of the databases and extensions forms a CDB/HCDG server that greatly reduces the effort required to create new statistical process, device, and yield simulation models. Examples of using the server to implement new models are described. Performance data demonstrate that the server is fast enough for use by analytical models during statistical simulation of macrocells, and is able to meet the representation needs of numerical simulation.>

geometry and field Database (CDB), for representing the results of IC process and device simulation, and its use in the PREDITOR process editor and statistical simulator.Using fast analytical models, process simulation and device parameter extraction for a CMOS inverter takes 1.3sec on a DECstation 3100, with database access taking 14-34% of that time.