This study characterizes the stress-induced subthreshold degradation effect in low-temperature polycrystalline silicon thin-film transistors (LTPS-TFTs) formed using sequential lateral solidified (SLS) crystallization on a glass substrate. The SLS process is adopted to improve carrier mobility by increasing the grain size. The deterioration of the innate subgrain boundaries that are induced by channel hot-electron stress causes these transistors to exhibit double-hump subthreshold characteristics which become more prominent as the width of the channel increases. A physical theory and a proposed transistor network model accurately explain and predict the width-dependent subthreshold degradation characteristics of these stress LTPS-TFTs.

1.
K.
Yoneda
,
R.
Yokoyama
, and
T.
Yamada
,
Tech. Dig. VLSI Symp.
2001
,
85
.
2.
Y.
Nakajima
,
Y.
Kida
,
M.
Murase
,
Y.
Toyoshima
, and
Y.
Maki
,
SID Int. Symp. Digest Tech. Papers
,
35
,
864
(
2004
).
3.
S.-W.
Lee
and
S.-K.
Joo
,
IEEE Electron Device Lett.
17
,
160
(
1996
).
4.
M.
Hatano
,
T.
Shiba
, and
M.
Ohkura
,
SID Int. Symp. Digest Tech. Papers
,
33
,
158
(
2002
).
5.
J. S.
Im
,
M. A.
Crowder
,
R. S.
Sposili
,
J. P.
Leonard
,
H. J.
Kim
,
J. H.
Yoon
,
V. V.
Gupta
,
H. J.
Song
, and
H. S.
Cho
,
Solid State Phys.
166
,
603
(
1998
).
6.
Y.
Uraoka
,
T.
Hatayama
,
T.
Fuyuki
,
T.
Kawamura
, and
Y.
Tsuchihashiet
,
Jpn. J. Appl. Phys., Part 1
40
,
2833
(
2001
).
7.
T.
Yoshida
,
Y.
Ebiko
,
M.
Takei
,
N.
Sasaki
, and
T.
Tsuchiya
,
Jpn. J. Appl. Phys., Part 1
42
,
1999
(
2003
).
8.
M.
Kimura
,
R.
Nozawa
,
S.
Inoue
, and
T.
Shimoda
,
Jpn. J. Appl. Phys., Part 2
40
,
L26
(
2001
).
9.
W. Y.
Huang
,
C. S.
Chang
, and
W. T.
Wang
,
Proc. Workshop on Active Matrix Liquid Crystal Display
(
2001
),
159
.
10.
Star-Hspice Manual
(
Avant! Corp.
,
California
,
2001
), Chap. 22, p.
182
.
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