Following the planarization of the first metal layer and the deposition of the initial ILD 1-1 capping layer, the ILD 1-2 deposition serves as the primary bulk insulating matrix for the subsequent Via 1 (V1) integration A2.The preceding ILD 1-1 typically functions as a thin etch stop and copper diffusion barrier, comparable to the ultra-thin etch stop layers utilized in advanced nodes to shorten the electric field path while maintaining reliability P3.ILD 1-2 provides the critical vertical separ