太陽能矽晶片目前已普遍被使用，大量的使用以及逐漸普及化造成矽材料的短缺，使得矽晶片的薄型化越來越重要。薄型化的過程中以及薄試片之加工過程中都容易造成試片表面之缺陷，在缺陷處容易有應力集中之現象，此缺陷也成為試片破裂之起始點。本研究利用有限單元分析軟體，首先探討奈米孔洞結構對於表面缺陷處應力集中現象之影響，再對不同形貌之奈米孔洞結構以及不同表面缺陷分別做不同參數之模擬分析。由於本研究中著重在探討缺陷附近之應力變化情形，因此採用局部法，只在缺陷附近建立奈米結構來模擬缺陷附近之情形。另外以銀當作正電極、鋁當作負電極建立太陽能電池疊層板結構，探討不同形式的疊層板結構是否對奈米結構的效果有所影響。實驗方面，我們可以由四點彎矩實驗中看出奈米結構的效果，並且由實驗結果去對分析結果作驗證。期望本研究之結果能在矽晶片薄型化之相關製程上提供參考。

Increasing uses of silicon chip in solar cell makes the thinning of silicon chip necessary. Surface defects are easily induced on chip during the thinning and machining processes. The stress concentration resulted from defects would be the source of crack and failure of silicon chips.
In this research, the finite element analysis was first used to investigate the effect of nano-structure on stress concentration caused by surface defect with different parameters for silicon chip. Since we focused on the stress distribution near the defect, nano-structures were introduced in the nearby area of defect in the analysis. The four-point bending tests of silicon chip were also performed to access the effect of nano-structure on the strength of silicon chip and compared with the results from simulation. For the solar cell models, positive silver and negative aluminum electrodes were added, and the effect of nano-structure with different patterns of solar cell were discussed. The results obtained in this research can provide some useful suggestions in the process of thinning silicon chip.

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