The growing need for integrated circuits for special applications in industries such as the automotive industry has motivated the development of CAE tools to aid in the complex task of IC design. These tools use standard cells or gate arrays as building blocks. Using CAE tools, the designer enters a logic description of the desired circuit, and the tools can automatically generate and verify the mask design. Logic and circuit simulators, design verification and mask preparation tools, all interfaced to a common design database, provide for design checking before fabrication. Silicon processing facilities provide fabrication of standard cell or gate array designs based on state-of-the-art MOS processes.