Fabrication of MFISFETs with Pt/SrBi2Ta2O9/Y2O3/Si gate structure by developing an etch-stop process

Abstract

A metal-ferroelectric-insulator-semiconductor field-effect transistor (MFISFET) was fabricated with an etch-stop process based on the selectivity between SrBi2Ta2O9 (SBT) and Y2O3. Depending on the selectivity with various Ar/Cl-2 gas mixture, we could find the acceptable thickness of Y2O3 for a successful etch-stop process. The electrical characteristics of the MFISFET fabricated with the developed etch-stop process showed no damage of the silicon surface of source/drain regions, resulting in good ferroelectric memory characteristics and programmable operation.