US 9,214,377: Methods for Silicon Recess Structure in a Substrate by Utilizing a Doping Layer

Embodiments of the present invention provide a methods for forming silicon recess structures in a substrate with good process control, particularly suitable for manufacturing three dimensional (3D) stacking of fin field effect transistor (FinFET) for semiconductor chips. In one embodiment, a method of forming recess structures in a substrate includes etching a first portion of a substrate defined by a second portion formed in the substrate until a doping layer formed in the substrate is exposed.