Molecular dynamics study on channeling and lateral straggle for sharp shallow junction formation: Low energy As-ion implantation

Abstract

We have investigated low-energy As-ion implantation by using an upgraded MDRANGE code to study the formation of sharp shallow junction depths. Simulations of 0.1 - 50 keV As-ion implantation into Si in the [100] direction and a 7 degrees tilt from the [100] direction show that channeling effects become unimportant below 2 keV. Even at the low energies considered in this work, it is shown that channeling must be carefully considered and that implantations into the [100] channel give sharp junctions close to the end of the range. Below 10 keV, As-ion implantation at a 7 degrees tilt is necessary for shallower junctions, because the profiles are estimated to be dominated more by channeling in the depth direction than by straggles in the lateral direction.