Abstract: A method includes receiving a wafer, measuring a surface topography of the wafer; calculating a topographical variation based on the surface topography measurement performing a single-zone alignment compensation when the topographical variation is less than a predetermined value or performing a multi-zone alignment compensation when the topographical variation is greater than the predetermined value; and performing a wafer alignment according to the single-zone alignment compensation or the multi-zone alignment compensation.

Abstract: A method includes forming a low-k dielectric layer over a substrate of a wafer, forming a first dielectric layer over the low-k dielectric layer, forming a second dielectric layer over the first dielectric layer, forming a stress tuning dielectric layer over the second dielectric layer, forming an opening in the stress tuning dielectric layer to expose a top surface of the second dielectric layer, and etching the stress tuning dielectric layer and the second dielectric layer to form a trench. The formation of the opening and the etching of the stress tuning dielectric layer are performed in separate etching steps. The method further includes etching the first dielectric layer to form a via opening connected to the trench, and filling the trench and the via opening to form a metal line and a via, respectively.

Abstract: A method includes forming a low-k dielectric layer over a substrate of a wafer, forming a first dielectric layer over the low-k dielectric layer, forming a second dielectric layer over the first dielectric layer, forming a stress tuning dielectric layer over the second dielectric layer, forming an opening in the stress tuning dielectric layer to expose a top surface of the second dielectric layer, and etching the stress tuning dielectric layer and the second dielectric layer to form a trench. The formation of the opening and the etching of the stress tuning dielectric layer are performed in separate etching steps. The method further includes etching the first dielectric layer to form a via opening connected to the trench, and filling the trench and the via opening to form a metal line and a via, respectively.

Abstract: An integrated circuit structure includes a substrate, a plurality of low-k dielectric layers over the substrate, a first dielectric layer over the plurality of low-k dielectric layers, and a metal line in the first dielectric layer. A stress tuning dielectric layer is over the first dielectric layer, wherein the stress tuning dielectric layer includes a first opening and a second opening. The metal line extends into the first opening. The second opening has a bottom substantially level with a top surface of the first dielectric layer. A second dielectric layer is over the first dielectric layer.

Abstract: An integrated circuit structure includes a substrate, a plurality of low-k dielectric layers over the substrate, a first dielectric layer over the plurality of low-k dielectric layers, and a metal line in the first dielectric layer. A stress tuning dielectric layer is over the first dielectric layer, wherein the stress tuning dielectric layer includes a first opening and a second opening. The metal line extends into the first opening. The second opening has a bottom substantially level with a top surface of the first dielectric layer. A second dielectric layer is over the first dielectric layer.