Design and evaluation of a minienvironment for semiconductor manufacture processes

A new minienvironment for controlling the process area from ambient air contamination was designed and evaluated. The new design has a buffer zone between the ambient and the process zones. A parametric study of this design using a Computational Fluid Dynamics (CFD) method was conducted for various cases. A full-scale experimental model was fabricated. The evaluation was completed by measurements of airflow patterns, zone pressure differentials and particle concentration levels for the fabricated minienvironment. It is concluded that this new minienvironment is capable of maintaining a cleanliness of less than one particle per cubic meter, and the buffer zone is effective in preventing cross contamination between the process and the ambient zones.