The development of 300mm metal and polysilicon plasma etch systems presents numerous technical challenges. The main efforts can be delineated as mainframe and integration, chamber development, and process characterization and development. With respect to system mainframe and integration, we discuss wafer handling in detail. Discussion of the chamber design effort includes decoupled plasma source development, the electrostatic wafer chuck, and gas feed and distribution as guided by the use of fluid flow simulation. Process and hardware performance data are presented as they illustrate design success.