Edge transistor elimination in oxide trench isolated N-channel metal-oxide-semiconductor field effect transistors

摘要

Bulk N-channel metal-oxide-semiconductor field effect transistors (MOSFETs) can suffer from parasitic edge transistor effects, unless several extra processing and masking steps are used. These edge devices increase the off-state current and degrade subthreshold slope for the N-MOSFETs. Parasitic edge transistors in oxide trench isolated N-MOSFETs, formed using selective epitaxial Growth of silicon, were caused by the boron ou-diffusion during high temperature process steps.