Effects of switching from <110> to <100> channel orientation and tensile stress on n-channel and p-channel metal-oxide-semiconductor transistors

摘要

We investigate the effects of switching from <110> to <100> channel orientation on NMOS and PMOS transistors. For NMOS transistors, we have experimentally demonstrated that there is negligible electron mobility degradation after the switching. The decrease in on-current (I_(on)) of <100> NMOS transistors is caused by an increase in the effective channel length due to a reduction in the lateral ion channeling of the source/drain extension implants and the halo implants. For PMOS transistors, the increase in hole mobility dominates over the reduction of lateral ion channeling, and thus I_(on) of <100> PMOS transistor increases. By exploiting the stress insensitivity of <100> PMOS transistors, we can use a single tensile liner to improve NMOS transistors while not degrading PMOS transistors instead of using a more complicated process involving a tensile stress liner for NMOS transistors and a compressive liner for PMOS transistors.