cmosfet $ h - ocw.nagoya-u.jp
TRANSCRIPT
3-1
CMOSFET
3-2nMOSFET
GS T DSV V V
212D GS T DS DSI V V V V
0DS GS TV V V
2 12D GS T DSI V V V
n oxW CL
2 22 A S F BS
T FB Fox
qN VV V
C
C FiFB M F
E EVq
VB
VS VG VD
VB
VS
VG
VD
p
LW
n n
3-3
0GS TV V
VT
VGS
ID
0 VTVGS
log( ID )
subthreshold
3-40GS TV V
S G D
x
y0n+ n+
p
B
qVBE
E
EC
EV
y
x = 0
MOS MOS (VG, VB
EC
EV-qVG
-q S
x0
EFi-q F
E
-qVB-qVGB
3-50GS TV V
npn
npn2
exp expn i BCBEC
B A B B
qD n qVqVI AW N k T k T
npn nMOS
IC ID
A W d
WB L
NA NA= ni exp(q F /kBT )
VBE S + VBS
VBC S + VBD
dexpi F
B
qn nk T
0
SS S
x S
Qd x xdx
0
0B S
S
ndx k Tdn x qQ
3-6
2S A SQ qN S 2S S
SS S
Q QC
2
exp 2 1 expS DSBD S F BS
ox B B
C qVk T qI VC q k T k T
Bn n
k TDq
2 2S S S F S S FQ Q C
0 1 2S SGS FB S BS T BS S F
ox ox
Q CV V V V VC C
1 S
ox
CnC
2
011 exp 1 exp DSB
D GS T BSB B B
qVk T q n qI n V V Vq nk T n k T k T
subthreshold1
ln(10)kTs nq
, ,
0GS TV V
VT 0 VT VBS = 0
3-7
nJ qR
OFFI q RdV
R :
-R
Jn
source drain
IOFF
R :
VGS [V]
I D[A
]
Subthershold
I D[A
]
EC
EV
3-8Shockley-Read-Hall (SRH)
1n T Tc nN f n T Te N f p T Tc pN f 1p T Te N f
ET
EC
EV
phononET
NT :
n p n pT
n p n p
c c np e eR N
c n c p e e
n n thc v
T Fi BE E k Tn n ie c n e
p p thc v
T Fi BE E k Tp p ie c n e
n, p : vth
E
k
2
T Fi B T Fi B
iE E k T E E k T
p i n i
np nRn n e p n e
1 7~ 10p T pN c s 1 7~ 10n T nN c s
fT :
1n T T n T TR c nN f e N f
1p T T p T Tc pN f e N f
n pT
n p n p
c n ef
c n c p e e
1n T T n T Tc nN f E e N f E1p T T p T Tc pN f E e N f E
/
11F BE E k Tf E
e *3 Bk T m
3-9SRH
OFF
, ~ 0n p
1 1T Fi B T Fi B
i TE E k T E E k T
p n
n NRc e c e
1 1T Fi B T Fi B
i TOFF E E k T E E k T
p n
qn NI dVc e c e
cn ~ cp
2coshi T
OFFT Fi B
qcn NI dVE E k T
1/co
sh(x
)
(ET EFi)/kBT
( EFi )
(deep level)
3-10
EC
EV
trap Coulomb
(trap-assisted band-to-band tunneling)
Acceptor Donor
ep : Dirac wellen : Coulomb well
2
1
T Fi B T Fi B
iAT E E k T E E k T
i iCoul Dirac
p F p n n
np nR Nn n e p n ec c
2
1
T Fi B T Fi B
iDT E E k T E E k T
i iDirac Coul
p p n F n
np nNn n e p n e
c c
fp BE k TF e fp SE q qF
1 5 33 2, , exp 1b
a b K a au Ku b u du
* 34 2, ,
3fp n nCoul n
nn
E m EEkT E q E
* 34 2,0,
3n nDirac n
n
m EEkT q E
* 34 2, ,
3p pp fpCoul
pp
m EE EkT E q F
* 34 2,0,
3p ppDirac
p
m EEkT q F
n C TE E E
p T VE E E
F : E F
ep : Coulomb wellen : Dirac well
3-11
(trap-assisted band-to-band tunneling)
(band-to-band tunneling)
0F FR BF e= 5/2
F0 = 1.9 x 107 V/cm
B = 4 x 1014 cm-1/2V-5/2s-1
Si :
y
x
x y
p
n+VD
G. A. M. Hurkx, et al., IEEE Trans. Electron Devices vol. 39, p. 331, 1992
3-12
GIDL (Gate Induced Drain Leakage)
VGS [V]
I D[A
/m
] trap-assisted band-to-band tunneling
band-to-band tunneling
total
no electron-hole generation
Simulation (L = 0.13 m, tox = 4 nm)VDS = 3V
3-13
Auger
EC
EV
2 2n i p iR a n np n a p np n
an ~ 8.3 x 10-32 cm6/sap ~ 1.8 x 10-31 cm6/s
3
3-14
EC
EV
- breakdown
Impact ionization
3-15Impact IonizationEC
EV
Egimpact ionization
n n p pG J J
n, p : impact ionization
nb En na e pb E
p pa e
F (V/cm) <2.4x105 5.3x105 <
an (cm-1) 2.6x106 6.2x105 5.0x105
bn (V/cm) 1.43x106 1.08x106 9.9x106
ap (cm-1) 2.0x106 5.6x105
bp (V/cm) 1.97x106 1.32x106
Eg
3-16
DAHCDrain Avalanche Hot Carrier injection
CHEChannel Hot Electron injection
SGHESecondary Generated Hot Electron injection
SHESubstrate Hot Electron injection
VB
VG VD
VG = VD
Source Drain
Gate
VB
VG VD
VG < VD
Source Drain
Gate
VB
Source Drain
Gate VB >> 0
VB
VG VD
Source Drain
GateVG < VD
|VB | > 0
3-17(Breakdown Voltage)Avalanche Breakdown (Bipolar Breakdown)
Impact ionization
Breakdown
+
ISUB
VDS
I D
VGS
1
1 2
2
33
4
4
5
5 6
6
n+ n+
S
B
DG
3-18
EC ~ 104 V/cm~ 5 x 104 V/cm
> (Ep~ 0.063 eV)
*
83
pS
Ev
m
107
106
105
102 103 104 105
(cm
/s)
106
( V/cm)
v = n E v = p E
3-19
0
01
nn
n
sat
EE
v
0n nE
n satv E E v
E
E
n n ox GS TdVI W C V V Vdy
0
01
nn ox GS T
n
sat
dVI W C V V VdV dyv dy
20
0
12
n oxD GS T DS DS
nDS
sat
W CI V V V VL V
v
0D
DS
IV
001 1 11 22 2
GS T GS TDsat
nnGS TGS T
satsat
V V V VVV VV V v Lv L
2012
n oxD Dsat
W CI VL
3-20
RS RD
RG
CGS CGD
CGB
Body
Drain
Gate
CSB CDB
Source
n+ n+
GateSource Drain
Body
3-21
RS RD
RG
CGS CGD
CGBCSB CDB
Body
Source Drain
Gate
DS DS D S DV V I R R
GS GS D SV V I R
VDS
ID
DS D S DV I R R
VGS
ID
GS D SV I R
3/ 22D S DI R I
RDRSRG
3/ 22D S DI R I
3-22
DI
ID
VGS = VDS
0
2 GSV
GS D GSD
V I dVI
=2VT
2GS T D DV V I I
VGS=VDS
RS
RD+RS
1 GS T D SV V I R
DS DV I
= 1/
RS, VT
VDS ~ 0.02V
F. J. G. Sanchez, et al., IEEE Trans. Electron Devices, vol. 49, p. 82, 2002
H. Katto, IEEE Electron Device Lett. vol. 18, p. 408, 1997
3-23
RS RD
RG
CGS CGD
CGBCSB CDB
Body
Source Drain
Gate
N N
P
N N
P
N N
P
Subthreshold
2oxWLC CGS
CGD
VGS > VT
DS
GS T
VV V1
23
oxWLCCGC
VGSVT
2oxWLC
oxWLC
CGB
VDS > 0
CGC
VT+VDS
CGD
CGS
23
oxWLC
CGSO CGDO
CGC
CGC CGSO, CGDO
22 113 2GS ox
XC WLCX
22 113 2GD oxC WLC
X
DS
GS T
VXV V
3-24
factor
tox, L, W 1/KV 1/K Subthreshold
NA KI 1/KC 1/Ktd 1/KPd 1/K2
R K
j K electro-migration
/(ns)
(V)( m)
tox (nm)
103
251210
120
5 x 104
15550
106
0.053.55-5
115
5 x 107
0.010.9-1.8
0.255
1970 1980 1990 2000
1/K
3-25
L
VT
VDS
VT
Drain Induced Barrier Lowering (DIBL)
n+ n+
n+ n+
punchthroughL
VDS
3-26
W
VT
W
2 BTT fb F
ox
QV VC
B W WBT B
Q WL Q L QQ QWL W
QBT , QB , QW < 0
QBT (QBT < 0 (nMOS
3-27(lightly doped drain)
SiO2
SiO2
SiO2
n+n+
n
GIDL
n+n+
N N
LDD
LDD
E y[V
/cm
]
y [ m]
LDDLDD
3-28(Halo)
n+n+
n n
p+
p
p+
V T/
V DS
H.-S. Huang, et al. International Symposium on Nano Science and Technology, 2004
3-29
thermionic emission (RLD:Richardson-Laue-Dushman)
Fowler-Nordheim
3 24 22 23
216
b
ox
mqEox
b
q Ej e
b Vox
oxox
ox
VEt
2 2
2 32
b
Bk TBmqk Tj e
bVox
EF
EF
3 23 24 22 2 1 1
3216
box b
ox
mqV
Eox
b
q Ej e
3-30
A. Gupta, et al. IEEE Electron Device Lett. vol.18, p. 580, 1997
tox
3-31High-k
tox
oxox
ox
Ct
tox
S. H. Lo et al., IEEE Electron Device Lett. Vol. 18, No. 5, p. 209, 1997
10-12A0.1 mx0.1 m
3-32
Sitox
pMOSFET
EC
EV
4.05eV
5.17eV
Nb 3.99-4.3Al 4.06-4.2Ta 4.12-4.25Mo 4.3-4.6Zr 3.9-4.05V 4.12-4.3Ti 3.95-4.33TaN 4.2-3.9
Re 4.72-5.0Ir 5.-5.7Pt 5.32-5.5RuO2 4.9-5.2
nMOS
pMOS
Co 4.41-5.0W 4.1-5.2Os 4.7-4.83Cr 4.5-4.6Ru 4.60-4.71Rh 4.60-4.71Au 4.52-4.77Pd 4.8-5.22Ni 4.5-5.3
WNx, TNxp+ polySi
n+ polySin+ polySiGe
p+ polySiGe0-0.51
High-k Si
3-33(silicon on insulator)
n+ n+ D < Wmax = Fully-depleted
D > Wmax Partially-depleted
D
subthreshold(W/Km)
Si 140SiO2 1.1
3-34SOI
N+ N+
A. Wei, M. Sherony, and D. A. Antoniadis, IEEE Trans. Electron Devices, vol. 45, p. 430, 1998.
3-35SOI Dynamic Pass Gate Leakage
n+ n+
0 VVCC VCC
n+ n+
0 VVCC0 V
VS = VCC 0
Ip
In
MOS subthreshold
Bipolar ID ~ hFE Ip
MOS
1~10 ns
VGS = VCC
3-36SiSi
SiGe SiGe
n+ n+
p- relaxed Si1-xGex
p- graded buffer Si1-yGey
P-Si substrate
strained Si
y = 0 x
SiO2
Si
Si
SiO2
http://www.miraipj.jp/ja/result/030704/06.pdf
3-37
Double-gate FIN-FET Surrounding gate
UC Berkeley
SiO2
Si
n+
n+
Si
LDD
W(