Low-frequency noise in nFinFETs of different dimensions processed in strained and non-strained SOI wafers
The results of low-frequency noise investigation in fully-depleted (FD) nFinFETs of Weff = 0.02 to 9.87 µm, Leff = 0.06 to 9.9 µm, processed on standard (SOI) and strained (sSOI) wafers are presented. It is shown that the McWhorter noise is typical at zero back gate voltage for the devices studie...
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Інститут фізики напівпровідників імені В.Є. Лашкарьова НАН України
2008
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| Zitieren: | Low-frequency noise in nFinFETs of different dimensions processed in strained and non-strained SOI wafers / N. Lukyanchikova, N. Garbar, V. Kudina, A. Smolanka, E. Simoen, C. Claeys // Semiconductor Physics Quantum Electronics & Optoelectronics. — 2008. — Т. 11, № 3. — С. 203-208. — Бібліогр.: 9 назв. — англ. |
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irk-123456789-1190492017-06-04T03:03:35Z Low-frequency noise in nFinFETs of different dimensions processed in strained and non-strained SOI wafers Lukyanchikova, N. Garbar, N. Kudina, V. Smolanka, A. Simoen, E. Claeys, C. The results of low-frequency noise investigation in fully-depleted (FD) nFinFETs of Weff = 0.02 to 9.87 µm, Leff = 0.06 to 9.9 µm, processed on standard (SOI) and strained (sSOI) wafers are presented. It is shown that the McWhorter noise is typical at zero back gate voltage for the devices studied and the density of the corresponding noisy traps in the SiO₂ portion of the gate oxide is, as a rule, much higher than that in the HfO2 portion. The results on the McWhorter noise are used for studying the behavior of the electron mobility µ and the free electron density NS in the channel at V* ≥ 0.4 V where V* is the gate overdrive voltage. It is also shown that the Linear Kink Effect (LKE) Lorentzians appear in the low-frequency noise spectra at an accumulation back gate voltage and that the parameters of those Lorentzians are different for the sSOI and SOI nFinFETs. This is the first observation of the LKE noise under a back-gate accumulation bias for sufficiently wide nMuGFET. 2008 Article Low-frequency noise in nFinFETs of different dimensions processed in strained and non-strained SOI wafers / N. Lukyanchikova, N. Garbar, V. Kudina, A. Smolanka, E. Simoen, C. Claeys // Semiconductor Physics Quantum Electronics & Optoelectronics. — 2008. — Т. 11, № 3. — С. 203-208. — Бібліогр.: 9 назв. — англ. 1560-8034 PACS 73.50.Td, 85.30.Tv http://dspace.nbuv.gov.ua/handle/123456789/119049 en Semiconductor Physics Quantum Electronics & Optoelectronics Інститут фізики напівпровідників імені В.Є. Лашкарьова НАН України |
| institution |
Digital Library of Periodicals of National Academy of Sciences of Ukraine |
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DSpace DC |
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English |
| description |
The results of low-frequency noise investigation in fully-depleted (FD)
nFinFETs of Weff = 0.02 to 9.87 µm, Leff = 0.06 to 9.9 µm, processed on standard (SOI)
and strained (sSOI) wafers are presented. It is shown that the McWhorter noise is typical
at zero back gate voltage for the devices studied and the density of the corresponding
noisy traps in the SiO₂ portion of the gate oxide is, as a rule, much higher than that in the
HfO2 portion. The results on the McWhorter noise are used for studying the behavior of
the electron mobility µ and the free electron density NS in the channel at V* ≥ 0.4 V where
V*
is the gate overdrive voltage. It is also shown that the Linear Kink Effect (LKE)
Lorentzians appear in the low-frequency noise spectra at an accumulation back gate
voltage and that the parameters of those Lorentzians are different for the sSOI and SOI
nFinFETs. This is the first observation of the LKE noise under a back-gate accumulation
bias for sufficiently wide nMuGFET. |
| format |
Article |
| author |
Lukyanchikova, N. Garbar, N. Kudina, V. Smolanka, A. Simoen, E. Claeys, C. |
| spellingShingle |
Lukyanchikova, N. Garbar, N. Kudina, V. Smolanka, A. Simoen, E. Claeys, C. Low-frequency noise in nFinFETs of different dimensions processed in strained and non-strained SOI wafers Semiconductor Physics Quantum Electronics & Optoelectronics |
| author_facet |
Lukyanchikova, N. Garbar, N. Kudina, V. Smolanka, A. Simoen, E. Claeys, C. |
| author_sort |
Lukyanchikova, N. |
| title |
Low-frequency noise in nFinFETs of different dimensions processed in strained and non-strained SOI wafers |
| title_short |
Low-frequency noise in nFinFETs of different dimensions processed in strained and non-strained SOI wafers |
| title_full |
Low-frequency noise in nFinFETs of different dimensions processed in strained and non-strained SOI wafers |
| title_fullStr |
Low-frequency noise in nFinFETs of different dimensions processed in strained and non-strained SOI wafers |
| title_full_unstemmed |
Low-frequency noise in nFinFETs of different dimensions processed in strained and non-strained SOI wafers |
| title_sort |
low-frequency noise in nfinfets of different dimensions processed in strained and non-strained soi wafers |
| publisher |
Інститут фізики напівпровідників імені В.Є. Лашкарьова НАН України |
| publishDate |
2008 |
| url |
http://dspace.nbuv.gov.ua/handle/123456789/119049 |
| citation_txt |
Low-frequency noise in nFinFETs of different dimensions processed in strained and non-strained SOI wafers / N. Lukyanchikova, N. Garbar, V. Kudina, A. Smolanka, E. Simoen, C. Claeys // Semiconductor Physics Quantum Electronics & Optoelectronics. — 2008. — Т. 11, № 3. — С. 203-208. — Бібліогр.: 9 назв. — англ. |
| series |
Semiconductor Physics Quantum Electronics & Optoelectronics |
| work_keys_str_mv |
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| first_indexed |
2025-07-08T15:08:50Z |
| last_indexed |
2025-07-08T15:08:50Z |
| _version_ |
1837091868121235456 |
| fulltext |
Semiconductor Physics, Quantum Electronics & Optoelectronics, 2008. V. 11, N 3. P. 203-208.
© 2008, V. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine
203
PACS 73.50.Td, 85.30.Tv
Low-frequency noise in nFinFETs of different
dimensions processed in strained and non-strained SOI wafers
N. Lukyanchikova1, N. Garbar1, V. Kudina1, A. Smolanka1, E. Simoen2 and C. Claeys2,3
1V. Lashkaryov Institute of Semiconductor Physics, NAS of Ukraine
45, prospect Nauky, 03028 Kyiv, Ukraine
Phone: +380445256453; e-mail: natali@isp.kiev.ua, kudinavaleriya@yahoo.com
2IMEC,75, Kapeldreef, B-3001 Leuven, Belgium
3KU Leuven, 10, Kasteelpark Arenberg, B-3001 Leuven, Belgium
E-mail: simoen@imec.be, claeys@imec.be
Abstract. The results of low-frequency noise investigation in fully-depleted (FD)
nFinFETs of Weff = 0.02 to 9.87 µm, Leff = 0.06 to 9.9 µm, processed on standard (SOI)
and strained (sSOI) wafers are presented. It is shown that the McWhorter noise is typical
at zero back gate voltage for the devices studied and the density of the corresponding
noisy traps in the SiO2 portion of the gate oxide is, as a rule, much higher than that in the
HfO2 portion. The results on the McWhorter noise are used for studying the behavior of
the electron mobility µ and the free electron density NS in the channel at V* ≥ 0.4 V where
V* is the gate overdrive voltage. It is also shown that the Linear Kink Effect (LKE)
Lorentzians appear in the low-frequency noise spectra at an accumulation back gate
voltage and that the parameters of those Lorentzians are different for the sSOI and SOI
nFinFETs. This is the first observation of the LKE noise under a back-gate accumulation
bias for sufficiently wide nMuGFET.
Keywords: low-frequency noise, FinFET, fully-depleted, SOI, sSOI, Linear Kink Effect.
Manuscript received 09.06.08; accepted for publication 20.06.08; published online 15.09.08.
1. Introduction
In order to overcome the current limitations of
traditional dimensional scaling, performance boosters
like strain and multiple gate architectures are currently
of strong interest. The combination of both by
fabricating for example n-channel FinFETs on strained-
Silicon-on-Insulator (sSOI) substrates may yield
additional drive current improvement compared with
standard SOI substrates. While this is aiming in the first
place to digital applications, the question arises what the
analog potential of such technologies is. An important
aspect there is the low-frequency (LF) noise behavior.
The fact that the sidewall channels are on (110) faces for
a standard (100) SOI substrate raises concerns regarding
a higher density of interface and bulk oxide traps, and,
hence, the LF noise. Another concern may be the
application of strain on the quality of the gate
oxide/silicon interface, which can be addressed by noise
measurements. It is the aim of the present work to
investigate the noise in n-channel triple gate MuGFETs
with a SiO2/HfO2/TiN gate stack, fabricated on sSOI and
SOI substrates, as a function of the device dimensions
and bias conditions. It is shown that for most devices
studied, a higher trap density is derived in the vicinity of
the SiO2/HfO2 interface compared with the bulk HfO2.
Only a minor impact of the strain has been noted. In
addition and maybe more of academic value is the first
observation of the Linear Kink Effect (LKE) noise under
a back-gate accumulation bias for sufficiently wide
nMuGFETs. In this case, a different behavior is found
between SOI and sSOI devices.
2. Experimental
The investigated devices were n-channel fully-depleted
(FD) FinFETs processed on both the standard (SOI) and
strained (sSOI) SOI wafers. The parameters of the
devices were as follows: h = 65 nm and 55 nm for SOI
and sSOI nFinFETs, respectively, Weff = 0.02 to
9.87 µm, Leff = 0.06 to 9.9 �m, where h is the fin height,
Weff and Leff are the effective fin width and length,
respectively. In the case of Weff = 0.02 µm the multiple
fin configuration was used where the fin number Nfin
was equal to 30. The full device width Z has been
calculated by the formula Z = Nfin·(2h + Weff). The gate
stack consisted of 2 nm HfO2 on the top of 1 nm
interfacial SiO2, so that one has for the equivalent oxide
Semiconductor Physics, Quantum Electronics & Optoelectronics, 2008. V. 11, N 3. P. 203-208.
© 2008, V. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine
204
thickness: tEOT = 1.9 nm. The gate electrode was 5 nm
MOCVD TiN with a 100 nm poly-Si cap. No channel
doping was used.
The drain current noise spectral density SI(f) within
the frequency range f = 0.7 Hz to 100 kHz was measured
on wafer at 0.3 V ≤ VGF ≤ 1.6 V, and VDS = 25 mV for
VGB = 0 (an accumulation back-gate voltage) where VGF,
VDS and VGB are the front gate, back gate and drain
voltage, respectively.
3. Results and discussions
1. The families of the drain current noise spectra
SI(f) measured at different VGF and VGB = 0 for the sSOI
and relatively long SOI devices of Weff = 0.02 µm are
shown in Fig. 1. It is seen that for the SOI FinFETs the
noise spectra are of the 1/f type up to sufficiently high
frequencies where the 1/f component is lost in the
Nyquist noise. It is also seen that for the sSOI FinFETs
the 1/f portion of the noise spectra is observed only at
f > 400 Hz while SI ~ (1/f)0.7 takes place at f < 400 Hz.
Therefore, an essential difference in the shape of the
noise spectra for the standard and strained devices of
Weff = 0.02 µm shows itself at f < 400 Hz. At the same
time, it has been found that for the SOI FinFETs of
Weff ≥ 0.12 µm the spectra similar to those shown in
Fig. 1b are typical. It should be noted that similar spectra
are also observed for short (Leff ≤ 0.16 µm) SOI devices
of Weff = 0.02 µm.
Fig. 2 demonstrates the dependences of SI
normalized for Leff and Z on the gate overdrive voltage
V* measured at f = 3 kHz (curves 1 to 3) at which the 1/f
noise prevails for both the sSOI and SOI FinFETs and at
f = 10 Hz (curves 4 and 5) that corresponds to the (1/f)0.7
noise. It is seen that SI does not depend on V* at
V* > (0.2–0.8) V for both the 1/f and (1/f)0.7 noise
components. It should be noted that such a behavior is
typical for the low-frequency noise of the McWhorter
type [1, 2].
It is known that the McWhorter model ascribes the
noise to the fluctuations of the number of electrons in the
channel accompanying the electron exchange between
the channel and the slow traps located in the gate
dielectric at various distances x from the Si/SiO2
interface. If those traps are distributed homogeneously
over x, the 1/f noise has to be observed. However, if the
density of the noisy traps, Not, decreases with increasing
x, the noise spectrum has to be of the (1/f)m shape where
m < 1 [1, 3]. Then the dependences SI ~ (1/f)0.7
considered above and observed at f < 400 Hz can be
explained by the decrease of Not with increasing x at
x > x0. The value of x0 can be estimated using the
formula x0 = λln[(2πf0τmin)–1] where λ = 0.1 nm is the
tunneling parameter, f0 = 400 Hz and τmin = 10–10 s [3],
which gives x0 = 1.5 nm. As to the 1/f noise showing
itself at f > 400 Hz in the sSOI devices, this noise
corresponds to the traps located at x < x0, i.e. more close
to the Si/SiO2 interface.
Fig. 1. Spectra of the drain current noise for the SOI (a) and
sSOI (b) FD nFinFETs of Weff = 0.02 µm measured at VGB = 0.
Fig. 2. Dependences of the drain current noise spectral density
normalized for Leff and Z on the gate overdrive voltage
measured at f = 3 kHz (1-3) and 10 Hz (4 and 5) for SOI (1)
and sSOI (2-5) nFinFETs of Weff = 0.02 µm (1, 2 and 4) and
9.87 µm (3 and 5); VGB = 0.
Semiconductor Physics, Quantum Electronics & Optoelectronics, 2008. V. 11, N 3. P. 203-208.
© 2008, V. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine
205
Fig. 4. Density of traps for SOI and sSOI nFinFETs of
different Leff and Weff located in the gate oxide at various
distances x from the SiO2 interface.
Fig. 3. Equivalent gate voltage noise normalized for Leff and Z
at different gate overdrive voltages for SOI nFinFETs of
Weff = (0.12–9.87) µm and Leff = 0.9 µm (a) and sSOI
nFinFETs of Weff = 0.02 µm and Leff = (0.16-2.9) µm (b)
measured at f = 3 kHz (1) and 10 Hz (2); VGB = 0.
The dependences of the value of SVGLeffZ on V*
where SVG is the spectral density of the equivalent gate
voltage noise determined by SVG = [SI / (gm)2], where gm
is the transconductance are shown in Fig. 3. As is seen,
the typical for the McWhorter noise plateaus where SVG
is independent of the gate overdrive voltage manifest
themselves in the range 0 < V* ≤ 0.4 V for both 1/f noise
(curve 1) and (1/f )0.7 noise (curve 2).
Fig. 4 presents the values of Not calculated by the
formula Not = ( fSVGLeffZC0
2) / q2kTλ, where SVG
corresponds to the above mentioned plateau, C0 is the
capacitance of the gate oxide per cm2, q is the electron
charge, k is the Boltzmann constant and T is the
temperature. The open circles and triangles in Fig. 4
correspond to the 1/f noise component and relate to the
traps located at x < x0 in the sSOI FinFETs and in the
SOI ones of some dimensions (Weff = 9.87 µm or
Weff = 0.02 µm and Leff = 0.16 µm) as well as to the traps
distributed homogeneously over x in the SOI FinFETs of
Weff = 0.02 µm and Leff > 0.16 µm. The data shown in
Fig. 4 by the dot center circles and triangles have been
found by application of the formula
Not = ( fSVGLeffZC0
2) / q2kTλ to the results measured for
the (1/f )0.7 noise at f = 10 Hz. Note that the frequency
f = 10 Hz corresponds to x = 1.93 nm.
It is seen from Fig. 4 that Not = (2 to 3)×1019 cm–
3eV–1 at x < x0 ≈ 1.5 nm while the lower values of Not
[Not = (4 to 8)×1018 cm–3eV–1] have been found at x > x0
for the sSOI devices and the SOI ones of Weff = 9.87 µm.
It is also seen that the values of Not responsible for both
the 1/f and (1/f)0.7 noise in the devices of those types are
practically independent of Weff and Leff. It should be
noted that the estimated value of x0 (1.5 nm) is close to
the thickness of the interfacial oxide layer (1 nm) used in
the gate stack. This suggests that the traps characterized
by the above mentioned higher density are located just in
that oxide.
As to the SOI FinFETs of Weff = 0.02 µm, it is seen
from Fig. 4 that in the case where Leff > 0.16 µm and the
traps are distributed homogeneously over x, the value of
Not decreases from 7×1018 cm–3eV–1 to 3×1018 cm–3eV–1
as far as Leff decreases from 2.9 to 0.4 µm. It is also seen
from Fig. 4 that in the case where Leff = 0.16 µm and the
values of Not are different at x < x0 and x > x0, they
appear to be relatively low, namely: Not = 2×1018 cm–
3eV–1 and Not = 9×1017 cm–3eV–1 for x < x0 and x > x0,
respectively.
2. The obtained noise results can be used when
considering the dimension behavior of the electron
mobility µ as well as the behavior of the dependences
I(V*) in the devices studied.
The values of µm corresponding to maximal values
of the transconductance are shown in Fig. 5 for the
devices of different types and dimensions. It is seen that:
(i) µm decreases with decreasing Leff (Fig. 5a); (ii) at not
too small Leff the values of µm for the sSOI devices are
higher than those for SOI (Fig. 5a and b); (iii) µm
increases with decreasing Weff at Weff > 0.9 µm and
becomes practically independent of Weff at Weff < 0.9 µm
(Fig. 5b). Note that the same features have been
observed previously in the 65 nm FD planar SOI
nMOSFETs [4].
It is known that the decrease of µm with decreasing
Leff can be connected with increasing Not [5]. The
increase of Not with increasing Weff could be also
responsible for the corresponding decrease of µm.
However, a comparison of Fig. 5 with Fig. 4 shows that
there is no correlation between µm(Leff, Weff) and
Not(Leff, Weff). Therefore, the dimension dependences of
µm observed are not connected with the dimension
dependences of Not.
Semiconductor Physics, Quantum Electronics & Optoelectronics, 2008. V. 11, N 3. P. 203-208.
© 2008, V. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine
206
Fig. 5. Electron mobility corresponding to the maximum of the
transconductance at different Leff (a) for SOI (1 and 3) and
sSOI (2 and 4) nFinFETs of Weff = 0.02 µm (1 and 2) and
9.87 µm (3 and 4) and at various Weff (b) for SOI (1) and sSOI
(2) nFinFETs of Leff = 0.9 µm; VGB = 0.
It should be noted that the higher values of µm in
FinFETs where Weff = 0.02 µm << 2h than in FinFETs
where Weff = 9.87 �m >> 2h (Fig. 5a) can be explained
by µside > µtop [6], where µside and µtop are the values of
µm for the sidewall and top portions of the channel.
However, it has been found that µside < µtop for nFinFETs
[7]. Moreover, the method proposed in [6] can be used
only in the case where µ ≠ µ(Weff). At the same time,
Fig. 5b demonstrates the increase of µm with decreasing
Weff at Weff > 0.9 µm for the FinFETs, where Weff >> 2h
and, hence, µm = µtop. Therefore, like for the 65 nm FD
planar SOI nMOSFETs [4], the increase of µtop with
decreasing Weff takes place in the FinFETs considered.
Then such an increase of µtop at Weff < 0.9 µm could be
responsible for the higher values of µm in the FinFETs of
Weff = 0.02 µm even under conditions where µside < µtop.
Fig. 6. Dependences of the drain current normalized for Leff
and Z on the gate overdrive voltage for sSOI FinFETs of
Leff = 0.9 µm and Weff = 0.02 µm (1) and 9.87 µm (2) measured
at VGB = 0.
As to the behavior of I with V*, it has been found
that the increase of I with increasing V* becomes
sublinear at V* ≥ 0.4 V (Fig. 6) that is at rather low V*
where such an effect cannot be related to the influence of
the series resistance and usually is attributed to the
decrease of the electron mobility with increasing V*. At
the same time, our noise measurements have shown that
SI ≠ SI(V*) at 0.1 V≤ V* ≤ 0.8 V (Fig. 2). Since for the
McWhorter noise SI ~ µ2, this suggests that µ ≠ µ(V*) in
the above mentioned range of V* and, hence, the
sublinear behavior of I(V*) at V* ≥ 0.4 V is not explained
by a decrease of µ. The possible reason for this effect is
the sublinear increase of the free electron density in the
channel NS with increasing V*. A similar situation has
been observed previously for the planar nMOSFETs [2].
3. It has been found that under conditions where an
accumulation voltage is applied to the back gate, the
LKE Lorentzians [8] appear in the noise spectra
measured at 1 V ≤ VGF ≤ 1.6 V for the sSOI and SOI
nFinFETs of Weff ≥ 0.9 µm (Fig. 7). It should be noted
that this is the first observation of the LKE noise under a
back-gate accumulation bias for sufficiently wide
nMuGFETs. The behavior of the parameters of those
LKE Lorentzians (the Lorentzian plateau [SI(0)]LKE and
time constant τLKE) are shown in Fig. 8. It is seen from
Fig. 8a that [SI(0)]LKE ~ τLKE that is typical for the LKE
Lorentzians [8] and that {[SI(0)]LKE/τLKE} ~ (Leff)–n
where n < 3 while n = 3 has been observed for planar
MOSFETs with similar lengths as in Fig. 8a [8]. Since
[SI(0)]LKE ~ µ2 [8], one of the reasons for this effect is the
decrease of µ with decreasing Leff.
As to the behavior of τLKE with VGF, it is seen from
Fig. 8b that: (i) the sSOI FinFETs are characterized by
much higher values of τLKE at one and the same values of
VGF; (ii) τLKE ≠ τLKE (Leff) at Leff ≥ 0.9 µm while the
values of τLKE for Leff = 0.4 µm appear to be lower than
for Leff ≥ 0.9 µm, and this effect is more strong for the
sSOI FinFETs than for the SOI ones. Since the
considered LKE Lorentzians have been observed at
Semiconductor Physics, Quantum Electronics & Optoelectronics, 2008. V. 11, N 3. P. 203-208.
© 2008, V. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine
207
Fig. 7. Spectra of the drain current noise measured at accumulation back-gate voltage VGB = –9.48 V for the SOI (a) and sSOI (b)
FD nFinFETs of Weff = 9.87 µm and Leff = 0.9 µm.
Fig. 8. Dependences of the LKE Lorentzian plateau on the time constant (a) and of the LKE Lorentzian time constant on the front
gate voltage (b) measured at VGB = –9.48 V for sSOI nFinFETs of Weff = 9.87 µm and Leff = 2.9 µm (1), 0.9 (2), and 0.4 (3).
V* < 1 V, where the values of τLKE are determined by the
electron valence band tunneling not only through the
gate oxide but also through the silicon film depletion
layer [9], this effect can be related with different
conditions for such tunneling in sSOI and SOI FinFETs.
4. Conclusions
1. The low-frequency noise of the McWhorter type
is typical at VGB = 0 for the nFinFETs investigated. For
the sSOI devices, the densities of the noisy traps located
in the gate oxide at x < 1.5 nm and x > 1.5 nm, where x
is the distance from the Si/SiO2 interface into the oxide,
are found to be Not = (2 to 3)×1019 cm–3eV–1 and Not = (4
to 8)×1018 cm–3eV–1, respectively, the values of Not are
practically independent of Weff and Leff; for the SOI ones
of Weff = 0.02 µm, the values of Not appear to be lower.
2. The LKE Lorentzians have been revealed in the
low-frequency noise spectra for the devices of
Weff ≥ 0.9 µm at 1 V ≤ VGF ≤ 1.6 V when measuring at an
Semiconductor Physics, Quantum Electronics & Optoelectronics, 2008. V. 11, N 3. P. 203-208.
© 2008, V. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine
208
accumulation back-gate voltage, and the parameters of
those Lorentzians are found to be different for the sSOI
and SOI nFinFETs.
3. The results obtained for the McWhorter noise
suggest that: (i) the dependences of µm and Not on the
device dimensions do not correlate; (ii) the reason for
the sublinear increase of I with increasing VGF observed
for the nFinFETs at V* ≥ 0.4 V is the sublinear increase
of NS but not the decrease of the electron mobility.
References
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submicron silicon MOSFETs // Solid-State
Electronics 43(5), p. 865-882 (1999).
2. N. Lukyanchikova, N. Garbar, V. Kudina,
A. Smolanka, M. Lokshin, E. Simoen and C.
Claeys, High gate voltage drain current leveling off
and its low-frequency noise in 65 nm fully-depleted
strained and non-strained SOI nMOSFETs // Solid-
State Electronics 52(5), p. 801-807 (2008).
3. R. Jayaraman and C. Sodini, A 1/f technique to
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