Silicon thickness monitoring strategy for FD-SOI 28nm technology

Abstract

The silicon thickness (Tsi) fluctuation monitoring on FD-SOI 28nm technology process is addressed by 2 different electrical characterization techniques. The first, capacitive, is adapted to within wafer variations and lot/wafer variations monitoring. The second, using the Idsat sensitivity to the Tsi in an addressable transistors array, allows to measure the local variations in the range of few tens of microns.