Recovery of microstructure and surface topography of grinding-damaged silicon wafers by nanosecond-pulsed laser irradiation
Recovery of microstructure and surface topography of grinding-damaged silicon wafers by nanosecond-pulsed laser irradiation
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DOI：
10.1088/0268-1242/24/10/105018
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发表时间：
2009-10-01
影响因子：
1.9
通讯作者：
Izunome, Koji
中科院分区：
文献类型：
--
作者：
Yan, Jiwang;Sakai, Shin;Izunome, Koji
用纳秒脉冲Nd:YAG激光照射表面经金刚石磨削加工的单晶硅片。通过透射电镜和原子力显微镜观察了表面形貌和表面结晶度的变化。结果表明，磨削过程中产生了非晶层、位错和微裂纹。然而，所有这些损伤都可以通过适当能量密度的单一激光脉冲消除，这也导致了晶圆表面的显著平滑。当使用过高的能量密度时，晶圆表面会形成微小的颗粒。据推测，这些粒子是在激光脉冲作用下从晶圆片表面蒸发的硅重新凝聚而产生的。用简化模型估计了激光辐照过程中的温升。研究结果表明，纳秒脉冲激光照射可能是处理磨削损伤硅片的有效方法。
Single crystalline silicon wafers whose surfaces were machined by diamond grinding were irradiated by a nanosecond-pulsed Nd:YAG laser. Changes in the subsurface crystallinity and surface topography were investigated by transmission electron microscopy and atomic force microscopy. It was found that the grinding process gave rise to amorphous layers, dislocations and micro cracks. However, all of this damage could be eliminated by a single laser pulse of suitable energy density, which also led to a remarkable amount of smoothing of the wafer surface. When excessively high energy densities were used, tiny particles were found to form on the wafer surface. It is speculated that these particles are produced by the recondensation of silicon boiled away from the wafer surface during the laser pulse. The temperature rise during laser irradiation was estimated using a simplified model. The results obtained in this study suggest that nanosecond-pulsed laser irradiation may be an effective approach for processing grinding-damaged silicon wafers.