Optimizing etch uniformity for alternating aperture phase shift masks on Etec Systems ' Tetra TM photomask etch system

A simple method for minimizing the glass etch non-uniformity in the Etec Systems’ TetraTM etch tool will be presented along with etch rate performance stability results. In this triple etch process, the final phase uniformity was improved from ± 5 o to ± 1.3 o phase shift at 248 nm without changing either processing chemistry or any other process parameters… CONTINUE READING