A semiconductor structure having improved adhesion between a low-k dielectric layer and the underlying layer and a method for forming the same are provided. The semiconductor substrate includes a dielectric layer over a semiconductor substrate, an adhesion layer on the dielectric layer wherein the adhesion layer comprises a transition sub-layer over an initial sub-layer, and wherein the transition sub-layer has a composition that gradually changes from a lower portion to an upper portion. A low-k dielectric layer is formed on the adhesion layer. Damascene openings are formed in the low-k dielectric layer. A top portion of the transition sub-layer has a composition substantially similar to a composition of the low-k dielectric layer. A bottom portion of the transition sub-layer has a composition substantially similar to a composition of the initial sub-layer.