论文部分内容阅读
多晶硅是目前应用最广泛的太阳能电池材料。为了降低硅片切割带来的损耗,直拉带状硅片的开发和应用引起业内广泛关注但电池制备过程中较高的碎片率会成为其应用的一大障碍。线带多晶硅片晶粒形状与分布与目前产线使用铸造多晶硅片截然不同,为此可通过研究直拉多晶硅片的力学性能来分析其相对易碎的原因,为改善其力学性能提供一定的指导依据。本文采用分子动力学理论研究线带多晶硅片的力学性能,并与常规的铸造多晶硅片进行了对比。研究了硅片尺寸、晶粒大小和空位对硅片力学性能的影响。对于两种硅片,减小硅片尺寸或者增加晶粒尺寸,可以改善多晶硅的力学性能。空位对线带多晶硅和铸造多晶硅的力学性能都有影响,空位缺陷越多,力学性能越差。其中空位缺陷对线带多晶硅片的断裂强度影响较大,对铸造多晶硅片的强度影响较小。
Polysilicon is currently the most widely used solar cell materials. In order to reduce the loss caused by the silicon wafer cutting, the development and application of the straight-pull ribbon wafer industry has drawn wide attention in the industry but the higher fragment rate in the battery preparation process will become a major obstacle for its application. The shape and distribution of the polycrystalline silicon wafers are quite different from those of the currently used polycrystalline silicon wafers. Therefore, the reasons for the relatively brittleness of the polycrystalline silicon wafers can be analyzed by studying the mechanical properties of the polycrystalline silicon wafers, which will provide some guidance for improving the mechanical properties. in accordance with. In this paper, molecular dynamics theory is used to study the mechanical properties of polycrystalline silicon wafers, which are compared with the conventional polycrystalline silicon wafers. The influence of the size of silicon wafer, grain size and vacancy on the mechanical properties of silicon wafers was investigated. For both wafers, reducing the size of the wafers or increasing the grain size can improve the mechanical properties of polycrystalline silicon. The vacancy affects the mechanical properties of both polysilicon and cast polysilicon. The more vacancies, the worse the mechanical properties. The vacancy defects have a great influence on the breaking strength of the polycrystalline silicon wafers, and have little effect on the strength of the polycrystalline silicon wafers.