Threshold voltage Vth variations in scaled (110) n/pMOSFETs are systematically investigated. Vth variations in (110) nMOSFETs and pMOSFETs with high channel dose are larger than those in (100) nMOSFETs and pMOSFETs, respectively. Physical origins of Vth variation enhancement in (110) MOSFETs are analyzed on the basis of the substrate impurity concentration dependence of the body effect and S factor variations. It is found that the depletion width variations due to boron ion channeling and the interface trap density variations enhance Vth variations in boron-doped (110) nMOSFETs and that the interface fixed charge variations enhance Vth variations in arsenic-doped (110) pMOSFETs. An undoped channel combined with a steep boron profile and moderate phosphorus doping into the surface are desirable to minimize Vth variations in (110) nMOSFETs and pMOSFETs, respectively.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering