Patent ID: 8999861
Filing Date: 2015-04-07
Classification: H01L

Abstract:
1. A method for fabricating a semiconductor structure on a semiconductor substrate, comprising: masking portions of the substrate to form a pattern of transistors; performing a pre-amorphization implant into selected open areas defining a channel stack underlying a gate for a plurality of transistor elements of a similar type; performing a carbon ion implantation into the selected open areas in addition to the pre-amorphization implant; performing a boron ion implantation into the selected open areas in addition to the carbon ion implantation so as to form a screening region for the transistor element; performing a solid phase epitaxy after the carbon and boron ion implantations to cause the amorphized portions to transform into crystalline structures; performing an activation anneal to activate the boron by rendering the boron substitutional; forming a threshold voltage control layer on the boron screening region of the transistor element; and forming an epitaxial channel layer on the threshold control layer of the transistor element.