A method and apparatus is provided for fabricating a damascene interconnection. The method begins by forming on a substrate an organosilicate dielectric layer, a capping layer on the organosilicate dielectric layer, and a resist pattern over the capping layer to define a first interconnect opening. The capping layer is etched through the resist pattern using a first etchant. The resist pattern is removed after etching the capping layer. The dielectric layer is etched through the capping layer using a second etchant different from the first etchant to form the first interconnect opening. An interconnection is completed by filling the first interconnect opening with conductive material.