METHODS FOR FORMING DEVICE ISOLATION FOR SEMICONDUCTOR APPLICATIONS

The present disclosure provide methods for forming nanowire structures with desired materials horizontal gate-all-around (hGAA) structures field effect transistor (FET) for semiconductor chips. In one example, a method of forming nanowire structures on a substrate includes forming a multi-material layer on a bottom structure on a substrate, wherein the multi-material layer includes repeating pairs of a first layer and a second layer, selectively removing the second layer from the multi-material layer from the substrate, and selectively oxidizing the bottom structure on the substrate after removing the second layer from the multi-material layer.