作为太阳能光伏系统中普遍使用的一种结构材料, 多晶硅一直是人们研究的焦点。为了研究不同波长激光与多晶硅材料相互作用的机理, 分别采用波长为532、1 064 nm单脉冲激光辐射多晶硅表面, 并用光学显微镜对不同激光能量密度表面烧蚀形貌进行了观察, 探究了导致材料表面裂纹萌生的物理机制。研究结果表明: 波长1 064 nm的激光辐照下, 随着激光能量密度的增大, 烧蚀面积大小先呈指数分布后呈线性分布, 而在波长为532 nm下, 烧蚀面积大小呈线性分布; 高斯型激光辐照多晶硅时, 光斑中心环向热应力最大, 最易发生应力损伤; 两种波长激光辐照多晶硅材料的主要损伤机制为热熔损伤和带有瞬态热冲击引发的解理破坏且前者更易发生。

As a kind of the common used structural material in solar PV system, Polycrystalline silicon had always been studied as a focus. In order to study the interaction mechanism between different laser wavelengths and polycrystalline silicon, polycrystalline silicon surface was respectively irradiated by the single pulse laser with wavelengths of 532 nm & 1064 nm in this paper. The surface ablation morphology was observed by the optical microscope and analyzed under the different laser energy density. The physical mechanism of the crack initiation of material surface was explored. The results indicate that: under the wavelength of 1064 nm laser, firstly ablation area size is exponential distribution and then fits a linear distribution with the increasing of the laser energy density .And in the wavelength of 532 nm, ablation area size is linear distribution; Thermal stress is the largest in spot center and the most vulnerable to stress damage as irradiated by Gaussian laser; Two wavelengths laser irradiation Polycrystalline Silicon mainly damage mechanism are hot melting damage and the dissociation damage caused by transient thermal shock. Meanwhile, the former is more likely to happen.