Strain relaxation in Si/Ge/Si nanoscale bars from molecular dynamics simulations

被引:15
作者
Park, Yumi [1 ]
Atkulga, Hasan Metin [2 ]
Grama, Ananth [2 ]
Strachan, Alejandro [1 ,3 ]
机构
[1] Purdue Univ, Sch Mat Engn, W Lafayette, IN 47907 USA
[2] Purdue Univ, Dept Comp Sci, W Lafayette, IN 47907 USA
[3] Purdue Univ, Birck Nanotechnol Ctr, W Lafayette, IN 47907 USA
基金
美国国家科学基金会;
关键词
elemental semiconductors; germanium; molecular dynamics method; nanostructured materials; potential energy functions; semiconductor heterojunctions; silicon; stress relaxation; FIELD-EFFECT TRANSISTORS; REACTIVE FORCE-FIELD; P-TYPE; SILICON; HETEROSTRUCTURES; POTENTIALS; INSULATOR; SHEAR;
D O I
10.1063/1.3168424
中图分类号
O59 [应用物理学];
学科分类号
摘要
We use molecular dynamics (MD) with the reactive interatomic potential ReaxFF to characterize the local strains of epitaxial Si/Ge/Si nanoscale bars as a function of their width and height. While the longitudinal strain (along the bars length) is independent of geometry, surface relaxation leads to transverse strain relaxation in the Ge section. This strain relaxation increases with increasing height of the Ge section and reduction in its width and is complete (i.e., zero transverse strain) for roughly square cross sections of Ge leading to a uniaxial strain state. Such strain state is desirable in some microelectronics applications. From the MD results, which are in excellent agreement with experiments, we derive a simple model to predict lateral strain as a function of geometry for this class of nanobars.
引用
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页数:6
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共 24 条
[1]   Ultrathin-body strained-Si and SiGe heterostructure-on-insulator MOSFETs [J].
Åberg, I ;
Ni Chléirigh, C ;
Hoyt, JL .
IEEE TRANSACTIONS ON ELECTRON DEVICES, 2006, 53 (05) :1021-1029
[2]   Heteroepitaxial integration of metallic nanowires: transition from coherent to defective interfaces via molecular dynamics [J].
Arumbakkam, Arvind ;
Davidson, Eric ;
Strachan, Alejandro .
NANOTECHNOLOGY, 2007, 18 (34)
[3]   MODIFIED EMBEDDED-ATOM POTENTIALS FOR CUBIC MATERIALS AND IMPURITIES [J].
BASKES, MI .
PHYSICAL REVIEW B, 1992, 46 (05) :2727-2742
[4]   MOLECULAR-DYNAMICS WITH COUPLING TO AN EXTERNAL BATH [J].
BERENDSEN, HJC ;
POSTMA, JPM ;
VANGUNSTEREN, WF ;
DINOLA, A ;
HAAK, JR .
JOURNAL OF CHEMICAL PHYSICS, 1984, 81 (08) :3684-3690
[5]   Atomistic simulations of solid-phase epitaxial growth in silicon [J].
Bernstein, N ;
Aziz, MJ ;
Kaxiras, E .
PHYSICAL REVIEW B, 2000, 61 (10) :6696-6700
[6]   Multiparadigm modeling of dynamical crack propagation in silicon using a reactive force field [J].
Buehler, MJ ;
van Duin, ACT ;
Goddard, WA .
PHYSICAL REVIEW LETTERS, 2006, 96 (09) :1-4
[7]   Comparison between classical potentials and ab initio methods for silicon under large shear [J].
Godet, J ;
Pizzagalli, L ;
Brochard, S ;
Beauchamp, P .
JOURNAL OF PHYSICS-CONDENSED MATTER, 2003, 15 (41) :6943-6953
[8]   Fabrication of strained-Si/strained-Ge heterostructures on insulator [J].
Gomez, Leonardo ;
Canonico, Michael ;
Kim, Meekyung ;
Hashemi, Pouya ;
Hoyt, Judy L. .
JOURNAL OF ELECTRONIC MATERIALS, 2008, 37 (03) :240-244
[9]   Asymmetric strain in nanoscale patterned strained-Si/strained-Ge/strained-Si heterostructures on insulator [J].
Hashemi, Pouya ;
Gomez, Leonardo ;
Hoyt, Judy L. ;
Robertson, Michael D. ;
Canonico, Michael .
APPLIED PHYSICS LETTERS, 2007, 91 (08)
[10]   CANONICAL DYNAMICS - EQUILIBRIUM PHASE-SPACE DISTRIBUTIONS [J].
HOOVER, WG .
PHYSICAL REVIEW A, 1985, 31 (03) :1695-1697