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そうりんはぎにわ
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1 /Si FET /Si FET Improvement of tunnel FET performance using narrow bandgap semiconductor silicide Improvement /Si hetero-structure of tunnel FET performance source electrode using narrow bandgap semiconductor silicide /Si hetero-structure source electrode 1, 1, 1, 2, 2, 2, 2, 2, 2, 1, 1 1, 2 H. Hasegawa 1, Y. Wu 1, J. Song 1, K. Kakushima 2, Y.Kataoka 2, A. Nishiyama 2, N. Sugii 2, H. Wakabayashi 2, K. Tsutsui 2, K. Natori 1, H. Iwai 1 Tokyo Tech. FRC 1, IGSSE 2 1

2 MOSFET 60mV/decade S = = 2.3 ln(10) kt q C d dv ( ln I ) + C C ox ox G d d > 60mV / decade Source Channel Drain Conventional MOSFET ON/OFF 2

3 Tunnel FET T. Schulz, MOS AK/GSA Workshop, Apl P source N channel Tunneling injection BTBT p + in + Si TFET ON 3

4 ON Mg 2 Si FET ON p + E g Ψ Surface FET E G, ε E G =1.12eV 0.67eV 0.75eV 0.85eV 1.3eV n p + Ec Ev Ψ Surface n Semiconductor Basic Data 2nd Edition, O.Madelung, Springer M. Baleva et al., ECSTransaction 8,1 (2007) p.151 T. Suemasu, et al., JJAP 45 (2006) L519 E G E V n FET source D.K.Mohata, S.Datta, et al., IEDM Tech. digest, (2011)

5 Si Tunnel FET Mg 2 Si/Si p + Mg 2 Si/n Si p + Si/n Si n channel Tunnel FET 5

6 Conductor L g Gate Source Channel p Mg 2 Si n Si BOX t ox Si sub Ohmic contact Conductor source concentration cm 3 channel concentration ~10 18 cm 3 oxide thickness : t ox 0.3 ~ 1.0 nm SOI thickness 10nm gate length : L g 100nm p + -Mg 2 Si 0.75eV 0.42eV n -Si p+-mg 2 Si n-si p + Mg 2 Si/n Si p + Si/n Si 0.48eV 1.12eV V g t ox 6

7 p + Mg 2 Si-nSi p + Si-nSi TFET Drain current (A/um) V D =1.0V p + Mg 2 Si/n Si ON p + Si/n Si V th =V g Id=1x10 8 (A/µm) Vth=0.6V,1.1V SS(mV/dec.)=7.1, Gate voltage(v) Gate voltage(v) Subthreshold Slope, SS (mv/dec.) p + Mg 2 Si/n Si SS p + Si/n Si p + Mg 2 Si/n Si p + Si/n Si ON SS 7

8 Drain current (A/µm) p + Mg 2 Si/n Si p + Si/n Si channel conc. cm 3 V D =1.0V Gate voltage(v) ON Current (A/µm) p + Mg 2 Si/n Si 1.38 V th =V g Id=1x10 8 (A/µm) V g V th +0.5V p + Si/n Si channel concentration(cm 3 ) ON p + Mg 2 Si/n Si 10 17

9 Drain current (A/µm) V D =1.0V t ox (nm) p + Mg 2 Si/n Si p + Si/n Si SS(mV/dec.) (T ox =1.0nm) p + Mg 2 Si: 12.2 p + Si: Gate voltage(v) ON Current (A/µm) p + Mg 2 Si/n Si V th =V g 9 Id=1x10 (A/µm) V g V th +0.5V p + Si/n Si Oxide thickness (nm) t ox ON p + Mg 2 Si ON SS t ox p + -Mg 2 Si/n-Si TFET 9

10 Tunnel FET p + Mg 2 Si/n Si p + Si/n Si ON SS Mg 2 Si Tunnel FET source 10

13 Simulation model Material material=polysilicon EG300=0.77 permittivity=20 affinity= ni=1e14 models cvt consrh auger bgn fermi ni.fermi print temp=300 models bbt.nonlocal qtunn.dir=1 bbt.nlderivs Nonlocal band to band tunneling: x end x start J(E) 13

14 cvt, consrh, auger, bgn, Fermi, ni.fermi, Lombardi CVT Model: Matthiessen s rule µ AC scattering with acoustic phonons: µ sr The second component, µsr, is the surface roughness factor µ b scattering with optical intervalley phonons Lombardi et al, A Physically Based Mobility Model for Numerical Simulation of Non Planar Devices, IEEE Trans. on CAD (Nov. 1988):

15 cvt, consrh, auger, bgn, Fermi, ni.fermi, Shockley Read Hall (SRH) Recombination SRH Concentration Dependent Lifetime Model carrier lifetimes, Roulston, D.J., N.D. Arora, and S.G. Chamberlain, Modeling and Measurement of Minority Carrier Lifetime versus Doping in Diffused Layers of n p Silicon Diodes, IEEE Trans. Electron Devices Vol. 29 (Feb. 1982): Law, M.E. et. al., Self Consistent Model of Minority Carrier Lifetime, Diffusion Length, and Mobility, IEEE Electron Device Letters Vol. 12, No. 8, Fossum, J.G. and D.S. Lee, A Physical Model for the Dependence of Carrier Lifetime on Doping Density in Nondegenerate Silicon, Solid State Electronics Vol. 25 (1982):

16 cvt, consrh, auger, bgn, Fermi, ni.fermi, Trap Assisted Auger Recombination 16

17 cvt, consrh, auger, bgn, Fermi, ni.fermi, semiconductor bandgap narrowing cvt, consrh, auger, bgn, Fermi, ni.fermi, Includes the effects of Fermi statistice into the calculation of the intrinsic concentration in expressions for SRH recombination. 17

18 D.K.Mohata, S.Datta, et al., IEDM Tech. digest, (2011)

19 19

MOSFET HiSIM HiSIM2 1

MOSFET HiSIM HiSIM2 1 MOSFET 2007 11 19 HiSIM HiSIM2 1 p/n Junction Shockley - - on-quasi-static - - - Y- HiSIM2 2 Wilson E f E c E g E v Bandgap: E g Fermi Level: E f HiSIM2 3 a Si 1s 2s 2p 3s 3p HiSIM2 4 Fermi-Dirac Distribution