Tuning of the work function of bilayer metal gate by in-situ atomic layer lamellar doping of AlN in TiN interlayer
Journal
Journal of Applied Physics
Journal Volume
122
Journal Issue
9
Date Issued
2017
Author(s)
Abstract
A thin TiN interlayer doped with AlN was introduced between the Pt and gate oxide to tailor the work function of the Pt/Ti1-xAlxNy bilayer metal gate electrode. Using the in-situ atomic layer lamellar doping technique, the AlN doping concentration in the thin Ti1-xAlxNy interlayer can be precisely controlled. With the increase in the nominal AlN lamellar doping percentage (DPAlN) from 0% to 50%, the work function of the Pt/Ti1-xAlxNy bilayer metal gate decreases from 4.49 eV and reaches a minimum of 4.19 eV as the DPAlN equals to 6.25%, and then increases to 4.59 eV with the DPAlN of 50%. The low work function (4.19 eV) of the Pt/Ti1-xAlxNy bilayer metal gate is appropriate for n-MOSFETs, which demonstrates a feasible way to achieve the low work function engineering of metal gate.
Publisher
American Institute of Physics Inc.
Type
journal article