Method for determining an endpoint and semiconductor wafer

A method for determining an endpoint during chemical-mechanical polishing of a semiconductor wafer (100, 200) is disclosed. The method comprises the steps of depositing on a first layer (106, 206) to be polished a second (sacrificial) layer (108, 208), the physical properties of the first layer (106, 206) being different from the physical properties of the second layer (108, 208). After that, the wafer (100, 200) is polished by chemical-mechanical polishing. Due to the different physical properties of the layers, a variation of the physical properties can be detected, and an endpoint can be determined on the basis of the detected variation. Further, a semiconductor wafer for use in a chemical-mechanical polishing process is disclosed.