Methods of fabricating a multi-layer semiconductor device such as a multi-layer damascene or inverted multi-layer damascene structure using only a single or reduced number of exposure steps. The method may include etching a precursor structure formed of materials with differential removal rates for a given removal condition. The method may include removing material from a multi-layer structure under different removal conditions. Further disclosed are multi-layer damascene structures having multiple cavities of different sizes. The cavities may have smooth inner wall surfaces. The layers of the structure may be in direct contact. The cavities may be filled with a conducting metal or an insulator. Multi-layer semiconductor devices using the methods and structures are further disclosed.