Patent ID: 7948307
Filing Date: 2011-05-24
Classification: H01L

Abstract:
1. A dual dielectric tri-gate field effect transistor comprising: a semiconductor substrate; an insulating layer on said substrate; at least one semiconductor fin on and extending upward from said insulating layer, said fin including first and second sidewalls and a top surface; a first dielectric layer having a first dielectric constant extending over the first and second sidewalls of the fin; a metal layer extending over the first dielectric layer; a second dielectric layer having a second dielectric constant, different than the first dielectric constant, on the top surface of the fin; and a gate electrode extending over the fin and the first and second dielectric layers, wherein the gate electrode and the first dielectric layer form first and second gates having a threshold voltage Vt1, and the gate electrode and the second dielectric layer form a third gate having a threshold voltage Vt2 different than Vt1.