Title :
Impact of a Nonideal Metal Gate on Surface Optical Phonon-Limited Mobility in High- κ Gated MOSFETs
Author :
Shah, Raheel ; De Souza, Maria Merlyne
Author_Institution :
De Montfort Univ., Leicester
Abstract :
The effects of surface phonon scattering in an nMOSFET with a high-k gate insulator and a nonideal metal gate are examined. The nonideal metal gate model depends on three parameters: (1) the density of electrons in the gate; (2) the electron effective mass; and (3) the high-frequency dielectric constant associated with the choice of gate metal. The impact of these parameters on surface optical (SO) mobility is demonstrated using TiN as an example. For the selected choice of parameters and Landau damping limits, the results indicate that SO phonon scattering does not seem to play a significant role in the mobility degradation of TiN/HfO2 MOSFETs for the entire range of sheet concentration.
Keywords :
Landau levels; MOSFET; electron density; electron mobility; electron-phonon interactions; hafnium compounds; high-k dielectric thin films; oxygen compounds; permittivity; semiconductor device models; surface phonons; titanium compounds; Landau damping limits; TiN-HfO2; electron effective mass; electrons density; high-frequency dielectric constant; high-k gate insulator; high-k gated MOSFET; mobility degradation; nMOSFET; nonideal metal gate model; sheet concentration; surface optical phonon-limited mobility; surface phonon scattering; Dielectrics and electrical insulation; Effective mass; Electron optics; High K dielectric materials; High-K gate dielectrics; MOSFET circuits; Metal-insulator structures; Optical scattering; Phonons; Tin; MOSFET; Metal gate; mobility; surface optical (SO) phonons;
Journal_Title :
Electron Devices, IEEE Transactions on
DOI :
10.1109/TED.2007.907135
