Laser bending of silicon sheet is a process to form three-dimensional microstructural silicon elements in an ambient environment. This study aims to investigate the process mechanism with the aid of both experimental and numerical analyses. To this end, a thin-film thermocouple was prepared to capture the temperature field within the heating zone of the laser beam. A new method was then developed to precisely determine the absorption factor by coupling numerical simulation of the laser bending results with the experimental results. It was found that each laser pulse causes a cycle of sharp temperature rise-drop in a silicon sheet. When the temperature in the heating zone is low, the sheet deforms elastically. When it is beyond the brittle–ductile transition temperature of silicon, however, plastic deformation in the sheet takes place and bending occurs. The bending angle becomes larger with increasing the number of laser beam scanning, once the temperature gradient in the scanning area is large enough.

Reference

Reference
1.
Chuang
,
W. C.
,
Lee
,
H. L.
,
Chang
,
P. Z.
, and
Hu
,
Y. C.
,
2010
, “
Review on the Modeling of Electrostatic MEMS
,”
Sensors
,
10
(
6
), pp.
6149
6171
.10.3390/s100606149
2.
Petersen
,
K. E.
,
1982
, “
Silicon as a Mechanical Material
,”
Proc. IEEE
,
70
(
5
), pp.
420
457
.10.1109/PROC.1982.12331
3.
Fruhauf
,
J.
,
Gartner
,
E.
, and
Jansch
,
E.
,
1999
, “
Silicon as a Plastic Material
,”
J. Micromech. Microeng.
,
9
(
4
), pp.
305
312
.10.1088/0960-1317/9/4/304
4.
Exner
,
H.
, and
Loschner
,
U.
,
2003
, “
Contactless Laser Bending of Silicon Microstructures
,”
Proc. SPIE
,
5116
, pp.
383
392
.10.1117/12.498961
5.
Nakajima
,
K.
,
Fujiwara
,
K.
, and
Pan
,
W. G.
,
2004
, “
Wave-Shaped Si Crystal Wafers Obtained by Plastic Deformation and Preparation of Their Solar Cells
,”
Appl. Phys. Lett.
,
85
(
24
), pp.
5896
5898
.10.1063/1.1834719
6.
Chen
,
G. F.
,
Xu
,
X. F.
,
Poon
,
C. C.
, and
Tam
,
A. C.
,
1998
, “
Laser-Assisted Microscale Deformation of Stainless Steels and Ceramics
,”
Opt. Eng.
,
37
(
10
), pp.
2837
2842
.10.1117/1.601821
7.
Chan
,
K. C.
,
Yau
,
C. L.
, and
Lee
,
W. B.
,
2000
, “
Laser Bending of Thin Stainless Steel Sheets
,”
J. Laser Appl.
,
12
(
1
), pp.
34
40
.10.2351/1.521911
8.
Shi
,
Y. J.
,
Yao
,
Z. Q.
,
Shen
,
H.
, and
Hu
,
J.
,
2006
, “
Research on the Mechanisms of Laser Forming for the Metal Plate
,”
Int. J. Mach. Tools Manuf.
,
46
(
12–13
), pp.
1689
1697
.10.1016/j.ijmachtools.2005.09.016
9.
Tongxi
,
X. Y.
, and
Zhang
,
L.
,
1996
,
Plastic Bending: Theory and Applications
,
World Scientific Publishing Co. Pvt. Ltd.
,
Singapore
, pp.
468
523
.
10.
Kaushish
,
J.
,
2010
,
Manufacturing Processes
,
2nd ed.
,
PHI Learning Pvt. Ltd.
,
New Delhi, India
, pp.
624
692
.
11.
Shen
,
H.
, and
Vollertsen
,
F.
,
2009
, “
Modelling of Laser Forming—An Review
,”
Comput. Mater. Sci.
,
46
(
4
), pp.
834
840
.10.1016/j.commatsci.2009.04.022
12.
Gartner
,
E.
,
Fruhauf
,
J.
,
Loschner
,
U.
, and
Exner
,
H.
,
2001
, “
Laser Bending of Etched Silicon Microstructures
,”
Microsyst. Technol.
,
7
(
1
), pp.
23
26
.10.1007/s005420000065
13.
Loschner
,
U.
,
Exner
,
H.
,
Gartner
,
E.
, and
Fruhauf
,
J.
,
2003
, “
Laser Bending of Silicon
,”
Photon Processing in Microelectronics and Photonics II
, Vol.
4977
, pp.
86
93
.
14.
Zhang
,
R. X.
, and
Xu
,
X. F.
,
2002
, “
Microscale Bending of Brittle Materials Using Pulsed and CW Lasers
,”
Photon Processing in Microelectronics and Photonics
, Vol.
4637
, pp.
291
296
.
15.
Zhang
,
X. R.
, and
Xu
,
X. F.
,
2005
, “
Laser Bending for High-Precision Curvature Adjustment of Microcantilevers
,”
Appl. Phys. Lett.
,
86
(
2
), p.
021114
.10.1063/1.1851617
16.
Wu
,
D. J.
,
Ma
,
G. Y.
,
Liu
,
S. A.
,
Wang
,
X. Y.
, and
Guo
,
D. M.
,
2010
, “
Experiments and Simulation on Laser Bending of Silicon Sheet With Different Thicknesses
,”
Appl. Phys. A: Mater. Sci. Process.
,
101
(
3
), pp.
517
521
.10.1007/s00339-010-5889-4
17.
Wu
,
D. J.
,
Zhang
,
Q.
,
Ma
,
G. Y.
,
Guo
,
Y. Q.
, and
Guo
,
D. M.
,
2010
, “
Laser Bending of Brittle Materials
,”
Opt. Lasers Eng.
,
48
(
4
), pp.
405
410
.10.1016/j.optlaseng.2009.09.009
18.
Wang
,
X. Y.
,
Xu
,
W. X.
,
Xu
,
W. J.
,
Hu
,
Y. F.
,
Liang
,
Y. D.
, and
Wang
,
L. J.
,
2011
, “
Simulation and Prediction in Laser Bending of Silicon Sheet
,”
Trans. Nonferrous Met. Soc. China
,
21
, pp.
S188
S193
.10.1016/S1003-6326(11)61086-8
19.
Suzaki
,
Y.
, and
Tachibana
,
A.
,
1975
, “
Measurement of the μM Sized Radius of Gaussian Laser Beam Using the Scanning Knife-Edge
,”
Appl. Opt.
,
14
(
12
), pp.
2809
2810
.10.1364/AO.14.002809
20.
Siethoff
,
H.
,
Brion
,
H. G.
, and
Schroter
,
W.
,
1999
, “
A Regime of the Yield Point of Silicon at High Temperatures
,”
Appl. Phys. Lett.
,
75
(
9
), pp.
1234
1236
.10.1063/1.124652
21.
Sumino
,
K.
,
1999
, “
Deformation Behavior of Silicon
,”
Metall. Mater. Trans. A
,
30
(
6
), pp.
1465
1479
.10.1007/s11661-999-0084-y
22.
Nakao
,
S.
,
Ando
,
T.
,
Shikida
,
M.
, and
Satol
,
K.
,
2006
, “
Mechanical Properties of a Micron-Sized SCS Film in a High-Temperature Environment
,”
J. Micromech. Microeng.
,
16
(
4
), pp.
715
720
.10.1088/0960-1317/16/4/007
23.
Roberts
,
S. G.
, and
Hirsch
,
P. B.
,
2006
, “
Modelling the Upper Yield Point and the Brittle–Ductile Transition of Silicon Wafers in Three-Point Bend Tests
,”
Philos. Mag.
,
86
(
25–26
), pp.
4099
4116
.10.1080/14786430600643308
24.
He
,
S. H.
,
Mench
,
M. M.
, and
Tadigadapa
,
S.
,
2006
, “
Thin Film Temperature Sensor for Real-Time Measurement of Electrolyte Temperature in a Polymer Electrolyte Fuel Cell
,”
Sens. Actuators A
,
125
(
2
), pp.
170
177
.10.1016/j.sna.2005.05.021
25.
Choi
,
H.
, and
Li
,
X. C.
,
2007
, “
Fabrication and Application of Micro Thin Film Thermocouples for Transient Temperature Measurement in Nanosecond Pulsed Laser Micromachining of Nickel
,”
Sens. Actuators A
,
136
(
1
), pp.
118
124
.10.1016/j.sna.2007.01.007
26.
Lingenfelser
,
D.
, and
Hess
,
P.
,
2007
, “
Laser-Induced Thermal Desorption Mass Spectrometry of Functionalized Silicon Surfaces
,”
Appl. Surf. Sci.
,
253
(
19
), pp.
7749
7754
.10.1016/j.apsusc.2007.02.169
27.
Willardson
,
R. K.
, and
Beer
,
A. C.
,
1977
,
Semiconductors & Semimetals
,
Academic Press
,
New York
, pp.
42
76
.
28.
Steen
,
W. M.
, and
Mazumder
,
J.
,
2010
,
Laser Material Processing
,
Springer
,
London
, pp.
89
127
.
You do not currently have access to this content.