Poswal H K, Garg Nandini, Sharma Surinder M, Busetto E, Sikka S K, Gundiah Gautam, Deepak F L, Rao C N R
Synchrotron Radiation Section, Bhabha Atomic Research Centre, Mumbai 400085, India.
J Nanosci Nanotechnol. 2005 May;5(5):729-32. doi: 10.1166/jnn.2005.109.
High-pressure structural behavior of silicon nanowires is investigated up to approximately 22 GPa using angle dispersive X-ray diffraction measurements. Silicon nanowires transform from the cubic to the beta-tin phase at 7.5-10.5 GPa, to the Imma phase at approximately 14 GPa, and to the primitive hexagonal structure at approximately 16.2 GPa. On complete release of pressure, it transforms to the metastable R8 phase. The observed sequence of phase transitions is the same as that of bulk silicon. Though the X-ray diffraction experiments do not reveal any size effect, the pressure dependence of Raman modes shows that the behavior of nanowires is in between that of the bulk crystal and porous Si.
利用角散射X射线衍射测量，研究了硅纳米线在高达约22吉帕斯卡压力下的高压结构行为。硅纳米线在7.5 - 10.5吉帕斯卡时从立方相转变为β-锡相，在约14吉帕斯卡时转变为Imma相，在约16.2吉帕斯卡时转变为原始六方结构。在压力完全释放时，它转变为亚稳的R8相。观察到的相变顺序与块状硅相同。虽然X射线衍射实验未揭示任何尺寸效应，但拉曼模式的压力依赖性表明纳米线的行为介于块状晶体和多孔硅之间。
