Long-lasting constant loading commonly exists in silicon-based microelectronic contact and can lead to the appearance of plastic deformation.Stress relaxation behaviors of monocrystalline silicon coated with amorphous...Long-lasting constant loading commonly exists in silicon-based microelectronic contact and can lead to the appearance of plastic deformation.Stress relaxation behaviors of monocrystalline silicon coated with amorphous SiO_(2)film during nanoindentation are probed using molecular dynamics simulation by varying the indenter’s size.The results show that the indentation force(stress)declines sharply at the initial and decreases almost linearly toward the end of holding for tested samples.The amount of stress relaxation of SiO_(2)/Si samples indented with different indenters during holding increases with growing indenter size,and the corresponding plastic deformation characteristics are carefully analyzed.The deformation mechanism for confined amorphous SiO_(2)film is depicted based on the amorphous plasticity theories,revealing that the more activated shear transformation zones(STZs)and free volume within indented SiO_(2)film promote stress relaxation.The phase transformation takes place to monocrystalline silicon,the generated atoms of Si-II and bct-5 phases within monocrystalline silicon substrate during holding are much higher than those for smaller indenter.展开更多
基金the National Natural Science Foundation of China(Nos.51375364,51575372)Doctor Funds of Taiyuan University of Science and Technology(No.20202004)。
文摘Long-lasting constant loading commonly exists in silicon-based microelectronic contact and can lead to the appearance of plastic deformation.Stress relaxation behaviors of monocrystalline silicon coated with amorphous SiO_(2)film during nanoindentation are probed using molecular dynamics simulation by varying the indenter’s size.The results show that the indentation force(stress)declines sharply at the initial and decreases almost linearly toward the end of holding for tested samples.The amount of stress relaxation of SiO_(2)/Si samples indented with different indenters during holding increases with growing indenter size,and the corresponding plastic deformation characteristics are carefully analyzed.The deformation mechanism for confined amorphous SiO_(2)film is depicted based on the amorphous plasticity theories,revealing that the more activated shear transformation zones(STZs)and free volume within indented SiO_(2)film promote stress relaxation.The phase transformation takes place to monocrystalline silicon,the generated atoms of Si-II and bct-5 phases within monocrystalline silicon substrate during holding are much higher than those for smaller indenter.
