TFET (HfO2 insulated dopingless field effect transistor with(metal implant) silvaco simulation)-1

why we need TFET?

TFET are attracting wide attention because of their low subthreshold swing and low OFF-state leakage current. Since the channel current is controlled by the tunneling mechanism on the source side, TFETs are more immune to short-channel effects (such as VT roll-off) unlike the conventional nanoscale MOSFETs . However, the low ON-state current in Si TFETs, due to poor band-to-band tunneling efficiency, is a major challenge to be overcome. This problem is being extensively studied using strain, hetero-structures, low bandgap materials, high-k gate insulators and nanowires. The other problem with the TFET is that in aggressively scaled devices, random variability in transistor performance due to random dopant fluctuations (RDF) can become significant. The effects of RDF, such as an unacceptably large increase in the OFF-state current, have recently been demonstrated in TFETs.

So now my code and parameter:-

first simulation parameter (i don't write simulation parameter you can extract from below figure)

code:-

go atlas

mesh space.mult=1

#

x.mesh loc=0 spac=.005

x.mesh loc=.002 spac=.005

x.mesh loc=.052 spac=.0005

x.mesh loc=.057 spac=.00005

x.mesh loc=.077 spac=.0005

x.mesh loc=.079 spac=.0005

x.mesh loc=.129 spac=.0005

x.mesh loc=.131 spac=.005

#

y.mesh loc=0 spac=.0005

y.mesh loc=.001 spac=.00005

y.mesh loc=.003 spac=.0005

y.mesh loc=.013 spac=.0005

y.mesh loc=.015 spac=.00005

y.mesh loc=.016 spac=.0005

# region

region num=1 material=air x.min=0 y.min=0

region num=2 material=silicon x.min=0.002 x.max=.052 y.min=.003 y.max=.013 ACCEPTORS=1e15

region num=3 material=silicon x.min=.052 x.max=.079 y.min=.003 y.max=.013 ACCEPTORS=1e15

region num=4 material=silicon x.min=.079 x.max=.129 y.min=.003 y.max=.013 ACCEPTORS=1e15

region num=5 material=HfO2 x.min=0.002 x.max=.129 y.min=.001 y.max=.003

region num=6 material=HfO2 x.min=0.002 x.max=.129 y.min=.013 y.max=.015

region num=7 material=AlN x.min=0.077 x.max=.079 y.min=.003 y.max=.013

qtx.mesh loc=0.04 spac=0.001

qtx.mesh loc=0.052 spac=0.0005

qtx.mesh loc=0.057 spac=0.0005

qtx.mesh loc=0.077 spac=0.0005

qtx.mesh loc=0.079 spac=0.0005

qtx.mesh loc=0.102 spac=0.001

qty.mesh loc=0.00 spac=0.005

qty.mesh loc=0.002 spac=0.0005

qty.mesh loc=0.003 spac=0.0005

qty.mesh loc=0.008 spac=0.0005

qty.mesh loc=0.012 spac=0.005

#electrode

electrode name=gate x.min=.057 x.max=.077 y.min=0 y.max=.001

electrode name=gate2 x.min=.057 x.max=.077 y.min=.015 y.max=.016

electrode name=drain x.min=0.002 x.max=.052 y.min=0.0 y.max=0.001

electrode name=drain2 x.min=0 x.max=.002 y.min=0.003 y.max=0.013 user.material=hafnium

electrode name=drain3 x.min=0.002 x.max=.052 y.min=0.015 y.max=0.016

electrode name=source x.min=.079 x.max=.129 y.min=0.0 y.max=0.001

electrode name=source2 x.min=.129 x.max=.131 y.min=0.003 y.max=0.013 material=platinum

electrode name=source3 x.min=.079 x.max=.129 y.min=0.015 y.max=0.016

#

MATERIAL MATERIAL=silicon me.tunnel=.44 mh.tunnel=.52 NC300=1e15 NV300=1e15

material material=hfo2 permittivity=21

material material=platinum eg300=5.93

material material=hafnium EG300=3.9 user.group=conductor user.default=SiO2

#

#doping uniform conc=1e17 p.type reg=4

#doping uniform conc=1e17 n.type reg=2

#contact

contact name=gate workfun=4.6

contact name=gate2 workfun=4.6 common=gate

contact name=drain2 workfun=3.9

contact name=source2 workfun=5.93

#model

models bbt.nonlocal bbt.forward bgn srh auger conmob fldmob CVT print

#

output val.band con.band qfn qfp e.field j.electron j.hole j.conduction j.total ex.field ey.field e.mobility h.mobility qss e.temp.h.temp j.disp

#method

method newton autonr itlimit=10 trap maxtrap=10

tonyplot nw_hidl_eq.str

#solve

solve init

solve vdrain=0.0

solve vdrain=0.01

solve vdrain=0.02

solve vdrain=0.03

solve vdrain=0.04

solve vdrain=0.05

log outf=nw_hidl.log

solve freq=1e6 name=gate vgate=0 vstep=0.05 vfinal=1

tonyplot nw_hidl.log

tonyplot nw_hidl_eq.str

quit

Simulation Result:-