Expansion of effective channel width for MOSFETs defined by novel T-shaped shallow trench isolation fabricated with SiON spacers and liners

A new fabrication process for realising T-shaped shallow trench isolation by the use of SiON spacers and liners is presented. This technique makes it possible to significantly increase the effective channel width of a metal oxide semiconductor field effect transistor (MOSFET), enhancing its drivability together with improving its subthreshold characteristics, without degrading fundamental isolation characteristics.