Abstract: Methods for doping a subfin region of a semiconductor fin structure include forming a fin on a substrate; forming an oxide material on the substrate and a portion of the fin that corresponds to a sub-fin region of the fin; forming a hard mask on a top-fin region of the fin that is disposed above the sub-fin region; exposing a surface of the sub-fin region by removing the oxide material from a surface of the sub-fin region and leaving a layer of the oxide material on the substrate; depositing a dopant material on the hard mask, the surface of the subfin region, and the layer of the oxide material on the substrate; and removing the hard mask from the top-fin region to expose a surface of the top-fin region. Devices constructed using the disclosed methods are also provided, and other embodiments are discussed.

Abstract: Direct focused ion beam (FIB) mixing is given as a method for patterning of metal silicide structures on a silicon surface. This technique allows the fabrication of submicron structures without the use of resist-based lithography methods. VLSI containing metal silicide connects, interconnects and structures may be prepared by the method. Fast semiconductor devices having good circuit speed and reduced RC time delay including the technologies MEMS, MOSFET, CMOS, pMOS, nMOS and BiCMOS result.