TY - JOUR
T1 - Atomic-scale silicidation of low resistivity Ni-Si system through in-situ TEM investigation
AU - Hou, An Yuan
AU - Ting, Yi Hsin
AU - Tai, Kuo Lun
AU - Huang, Chih Yang
AU - Lu, Kuo Chang
AU - Wu, Wen-Wei
N1 - Publisher Copyright:
© 2020 Elsevier B.V.
Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2021/2/1
Y1 - 2021/2/1
N2 - Nickel silicide has many advantages, such as low resistivity and low formation temperature; therefore, it has been widely used in the fields of solar cells, transistors and complementary metal-oxidesemiconductor (CMOS) devices. To obtain high-quality nickel-silicide thin film, solid-state reaction is a convenient and efficient fabrication method. For better understanding of the dynamic formation mechanism, we used in-situ transmission electron microscopy (TEM) to record the diffusion behavior during the heating process. In this work, three-steps annealing process to synthesize different nickel silicides corresponding to the various formation temperatures were investigated systematically. At 250 °C, the product of the first-step annealing was inverted-triangle Ni2Si, embedded in the Si substrate. Then, well-distributed NiSi thin film was synthesized, having the lowest resistivity among Ni-Si system at 400 °C. Finally, NiSi2, a Si-rich product, would form during the third-step annealing at 600 °C. NiSi2 product and Si substrate have small lattice mismatch; thus, the epitaxial relationship would be observed. We provide the evidence of diffusion behaviors and structural identification of Ni-Si system. Furthermore, these results are beneficial for the formation of specific nickel silicides, which is expected to optimize the fabrication of microelectronics.
AB - Nickel silicide has many advantages, such as low resistivity and low formation temperature; therefore, it has been widely used in the fields of solar cells, transistors and complementary metal-oxidesemiconductor (CMOS) devices. To obtain high-quality nickel-silicide thin film, solid-state reaction is a convenient and efficient fabrication method. For better understanding of the dynamic formation mechanism, we used in-situ transmission electron microscopy (TEM) to record the diffusion behavior during the heating process. In this work, three-steps annealing process to synthesize different nickel silicides corresponding to the various formation temperatures were investigated systematically. At 250 °C, the product of the first-step annealing was inverted-triangle Ni2Si, embedded in the Si substrate. Then, well-distributed NiSi thin film was synthesized, having the lowest resistivity among Ni-Si system at 400 °C. Finally, NiSi2, a Si-rich product, would form during the third-step annealing at 600 °C. NiSi2 product and Si substrate have small lattice mismatch; thus, the epitaxial relationship would be observed. We provide the evidence of diffusion behaviors and structural identification of Ni-Si system. Furthermore, these results are beneficial for the formation of specific nickel silicides, which is expected to optimize the fabrication of microelectronics.
KW - In-situ TEM
KW - Ni-Si system
KW - Nickel silicide
KW - Silicidation
KW - Solid-state reaction
UR - http://www.scopus.com/inward/record.url?scp=85092490588&partnerID=8YFLogxK
U2 - 10.1016/j.apsusc.2020.148129
DO - 10.1016/j.apsusc.2020.148129
M3 - Article
AN - SCOPUS:85092490588
VL - 538
JO - Applied Surface Science
JF - Applied Surface Science
SN - 0169-4332
M1 - 148129
ER -