Abstract: A barrier for terminating the edge of a semiconductor die such as a dynamic random access memory device is disclosed. The barrier reduces contamination of the dielectric layers such as TEOS and BPSG from mobile ions which are inherent in fabrication materials. While the barrier can be formed at many points in the die fabrication process, its formation is preferably incorporated into the Metal1 mask, thereby preventing the need for an additional mask step. The barrier, if formed with the Metal1 mask, would therefore be formed from the material of the Metal1, conventionally tungsten, a tungsten alloy, or other metals.