Influences of annealing conditions on flatband voltage properties using continuously workfunction-tuned metal electrodes

Abstract

This paper reports a systematic investigation of flatband voltage (Vfb), properties for HfO2-SiO2-Si capacitors using metal alloy electrodes of Pt-W alloy as a means of tuning work function (WF). It was found that the value of Vfb, for W (lower WF) is retained after forming gas annealing (FGA) and oxidizing gas annealing (OGA) processes, while that for Pt (higher WF) strongly depends on the annealing condition. The difference in Vfb, between Pt and W is 0.34 V at most, which is smaller compared with the WF difference of 0.8 eV.