Extraction of Channel Electron Effective Mobility in InGaAs/Al $_{\bf 2}$O$_{\bf 3}$ n-FinFETs

A compact set of equations based on the multiple subbands quasi-ballistic transport theory is developed, and is used to investigate the channel electron effective mobility in recently reported In<sub>0.53</sub>Ga<sub>0.47</sub>As/Al<sub>2</sub>O<sub>3</sub> tri-gate n-FinFET. The extracted electron effective mobility μn is around 370 cm<sup>2</sup>/V·s at low V<sub>g</sub> - V<sub>th</sub> bias at room temperature and decreases with increasing V<sub>g</sub>, and increases with increasing temperature (240-332K). It is very different from the case of Si n-MOSFETs, where the electron mobility decreases with increasing temperature. The low channel effective mobility and the ab-normal temperature dependence of μ<sub>n</sub> are ascribed to the high acceptor interface trap and border trap energy densities in the conduction band energy of InGaAs. The ballistic channel resistance R<sub>Ball</sub> at low Vds is calculated and compared with the measured channel resistance R<sub>CH</sub>. The low transmission coefficient T = R<sub>Ball</sub>/R<sub>CH</sub> ≈ 0.06 to 0.05 indicates that there is a large room to improve the InGaAs/Al<sub>2</sub>O<sub>3</sub> n-FinFET performance.

[1]  S. Luryi.  Quantum capacitance devices , 1988 .

[2]  F. Hsu,et al.  Relationship between MOSFET degradation and hot-electron-induced interface-state generation , 1984, IEEE Electron Device Letters.

[3]  P. D. Ye,et al.  Positive bias temperature instability degradation of InGaAs n-MOSFETs with Al2O3 gate dielectric , 2011, 2011 International Electron Devices Meeting.

[4]  M. Lundstrom,et al.  A compact scattering model for the nanoscale double-gate MOSFET , 2002 .

[5]  P. D. Ye,et al.  First experimental demonstration of gate-all-around III–V MOSFETs by top-down approach , 2011, 2011 International Electron Devices Meeting.

[6]  D. Schroder.  Semiconductor Material and Device Characterization , 1990 .

[7]  J. S. Blakemore.  Approximations for Fermi-Dirac integrals, especially the function F12(η) used to describe electron density in a semiconductor , 1982 .

[8]  Jerry R. Meyer,et al.  Band parameters for III–V compound semiconductors and their alloys , 2001 .

[9]  J.D. Plummer,et al.  Electron mobility in inversion and accumulation layers on thermally oxidized silicon surfaces , 1980, IEEE Transactions on Electron Devices.

[10]  S. Takagi,et al.  On the Universality of Inversion Layer Mobility in Si Mosfet's: Part 11-effects of Surface Orientation , 1994 .

[11]  Yuan Taur,et al.  A Distributed Model for Border Traps in Al 2 O 3 − InGaAs MOS Devices , 2011 .

[12]  M. Shur,et al.  Low ballistic mobility in submicron HEMTs , 2002, IEEE Electron Device Letters.

[13]  T. Numata,et al.  Experimental study on carrier transport mechanism in ultrathin-body SOI nand p-MOSFETs with SOI thickness less than 5 nm , 2002, Digest. International Electron Devices Meeting,.

[14]  S. Takagi,et al.  Impact of Fermi level pinning inside conduction band on electron mobility of InxGa1−xAs MOSFETs and mobility enhancement by pinning modulation , 2011, 2011 International Electron Devices Meeting.

[15]  S. Takagi,et al.  On the universality of inversion layer mobility in Si MOSFET's: Part I-effects of substrate impurity concentration , 1994 .

[16]  A. Hikavyy,et al.  Advancing CMOS beyond the Si roadmap with Ge and III/V devices , 2011, 2011 International Electron Devices Meeting.

[17]  G. Bersuker,et al.  InGaAs MOSFET performance and reliability improvement by simultaneous reduction of oxide and interface charge in ALD (La)AlOx/ZrO2 gate stack , 2009, 2009 IEEE International Electron Devices Meeting (IEDM).

[18]  A. Toriumi,et al.  Accurate characterization of electron and hole inversion-layer capacitance and its impact on low voltage operation of scaled MOSFETs , 1998, International Electron Devices Meeting 1998. Technical Digest (Cat. No.98CH36217).

[19]  P. Ye,et al.  First experimental demonstration of 100 nm inversion-mode InGaAs FinFET through damage-free sidewall etching , 2009, 2009 IEEE International Electron Devices Meeting (IEDM).

[20]  T. Ma,et al.  Mobility measurement and degradation mechanisms of MOSFETs made with ultrathin high-k dielectrics , 2004, IEEE Transactions on Electron Devices.

[21]  S. T. Ng,et al.  Impact of surface roughness on silicon and germanium ultra-thin-body MOSFETs , 2004, IEDM Technical Digest. IEEE International Electron Devices Meeting, 2004..

[22]  G. Dewey,et al.  Advanced High-K Gate Dielectric for High-Performance Short-Channel In 0 . 7 Ga , 2009 .

[23]  S. M. Sze,et al.  Physics of semiconductor devices , 1969 .

[24]  W. Shockley,et al.  Diffusion and Drift of Minority Carriers in Semiconductors for Comparable Capture and Scattering Mean Free Paths , 1962 .