Schottky barrier height modulation of NiGe/Ge junction by P and chalcogen (S, Se, or Te) co-introduction for metal source/drain Ge nMOSFETs

The profiles and J-V characteristics of P- and/or chalcogen (S, Se, or Te)-introduced Ge substrates and NiGe/Ge diodes have been investigated for a Ge nMOSFET with a NiGe source/drain. We found that chalcogen and P co-introduction caused a greater increase in the number of electrons in Ge than only P introduction. Moreover, P introduction and P and chalcogen co-introduction resulted in lower (higher) Schottky barrier height (SBH) values for NiGe/nGe (NiGe/pGe) diodes than no impurity introduction. Te and P co-introduction was most effective in modulating the SBH.