Memory device including a perforated dielectric bridge layer and method for forming the same

A method of forming a device structure, comprising:

• forming a plurality of alternating stacks of insulating layers and sacrificial material layers that are laterally spaced apart from each other by lateral isolation trenches that laterally extend along a first horizontal direction;
• forming sacrificial lateral isolation wall structures in the lateral isolation trenches;
• forming a perforated dielectric bridge layer over the plurality of alternating stacks and sacrificial lateral isolation wall structures, wherein the perforated dielectric bridge layer comprises rows of elongated openings therethrough, and wherein each row of elongated openings overlies a respective one of the sacrificial lateral isolation wall structures and is arranged along the first horizontal direction;
• removing the sacrificial lateral isolation wall structures through the rows of elongated openings without removing the plurality of alternating stacks or the perforated dielectric bridge layer;
• and
• replacing the sacrificial material layers with at least electrically conductive layers.