本文使用有限元素數值分析方法探討磊晶過程中矽基板晶邊接觸應力問題。為了改善基板與載台在磊晶過程中，因接觸應力導致矽基板產生缺陷，設計了四種晶邊幾何形狀，並使用ABAQUS有限元素法分析軟體進行動態分析，建立數值模型模擬磊晶過程中載台旋轉與基板接觸之運動，得到矽基板應力分佈與歷程。透過座標轉換將數值分析之結果轉換至滑移系統上之分解剪應力，並觀察表面分解剪應力的大小與分佈，以此為準則判斷晶邊幾何形狀的優劣。我們發現當矽基板之斜切長度較長時，表面分解剪應力之大小與分佈範圍會比斜切長度較短者小。斜切角度對於表面分解剪應力的影響較小，然而仍須有適當的斜切角度，不可有過大角度，使得矽基板邊緣出現過大的應力集中現象。

In the epitaxial process, the silicon substrate rotates at a high speed and hence its edge is in contact with the carrier of epitaxial machine. The contact stress often cause slip lines and crack on the surface of silicon substrate near the edge of contact. Those defects can affect the quality of epitaxy. In this research, we designed four different edge geometries of silicon wafer, and analyzed the stress field of silicon wafers during the rotation process. The analyses were carried out by finite element models of the dynamic contact process between silicon water and carrier. The simulated results were then transformed to the slip coordinate systems of silicon to obtain the resolved shear stress (RSS) field in each slip system. The influence of the edge design on the magnitude and distribution of RSS on the surface of silicon wafers are discussed. The longer cutting length, the lower RSS values are. Also, the cutting length reduces the magnitudes of RSS more effectively than the cutting angle. Besides, two-point contact condition is better than one-point contact condition. At last, the best edge geometry of the wafer is model 3.

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