SHALLOW TRENCH ISOLATION ETCH PROCESS

Methods for fabricating one or more shallow trench isolation (STI) structures are provided herein. In some embodiments, a method for fabricating one or more shallow trench isolation (STI) structures may include providing a substrate having a patterned mask layer disposed thereon to define one or more STI structures. The substrate may be etched using a plasma formed from a process gas mixture to form one or more STI structures on the substrate, wherein the process gas mixture comprises a fluorine-containing gas and either a fluorocarbon-containing gas or a hydrofluorocarbon-containing gas.