定向凝固多晶硅在微纳尺度下的力学性能研究

发布时间：2018-04-28 10:48

本文选题：纳米压痕测试系统 + 多晶硅　；参考：《材料导报》2017年14期

【摘要】：采用纳米压痕测试系统测试了定向凝固多晶硅沿晶体生长方向横/纵截面的硬度与弹性模量,分析了其受组织各向异性影响的变化规律。使用连续刚度方法借助玻氏压头采集压痕开裂前的硬度与弹性模量,并测量压痕开裂后裂纹尖端到压痕中心点的距离,一次性计算出材料的断裂韧性,避免了开裂对硬度以及弹性模量的影响。结果表明:横截面(110)面的硬度与弹性模量均低于纵截面(111)面,但断裂韧性呈现相反趋势。借助3D原位扫描功能扫描压痕裂纹的三维形貌,发现裂纹主要由剪切滑移台阶所形成。拟合不同载荷下的裂纹长度以及压痕尺寸得出临界压痕尺寸,该值与运用理论推导得出的临界压痕尺寸的结果一致。
[Abstract]:The hardness and elastic modulus of directionally solidified polysilicon along the transverse / longitudinal section along the crystal growth direction were measured by nano-indentation test system. The continuous stiffness method is used to collect the hardness and elastic modulus before indentation cracking with the help of Bohl indentation head, and the distance from the crack tip to the indentation center after indentation cracking is measured, and the fracture toughness of the material is calculated at one time. The effect of cracking on hardness and elastic modulus is avoided. The results show that the hardness and elastic modulus of cross section (110) plane are lower than that of longitudinal section (111) plane, but the fracture toughness shows the opposite trend. It is found that the crack is mainly formed by shear-slip step with the help of 3D in-situ scanning function to scan the three-dimensional morphology of indentation crack. The critical indentation size is obtained by fitting the crack length and indentation size under different loads, which is consistent with the critical indentation size obtained by theoretical derivation.
【作者单位】：太原理工大学材料科学与工程学院;新材料界面科学与工程教育部重点实验室;先进镁基材料山西省重点实验室;
【基金】：山西省回国留学人员科研资助项目(2013-029)
【分类号】：TN304.12

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