隨著晶錠尺寸的擴大，切割後晶圓表面不平整的問題日益顯著，這不僅增加了後續半導體製程的難度與成本，還可能導致材料浪費並降低製程效率。根據本研究的觀察，晶圓翹曲主要由熱膨脹不均與銅線震動兩個因素引起。其中，熱膨脹不均是由於不同深度的晶錠在切割過程中受熱和散熱不均，導致各區域的熱膨脹程度不同，進而使晶圓表面產生高低不平的形變。鋸線震動則會在切割過程中引起晶圓表面的局部不平整，但其影響範圍較小，主要造成局部形貌的變異。本研究認為熱膨脹不均是導致晶圓整體表面形變的主要原因，並因此著重探討了不同切割條件下的熱膨脹行為及其對晶圓表面的影響。
研究採用了直徑300mm、長度180mm的晶錠模型，通過數值模擬工具分析了切割過程中的溫度分布，並且將模擬結果與實驗數據進行比對。模擬過程中，調整外圍漿料噴灑流速，研究了其對不同切割深度下的溫度影響。最終，研究表明改變漿料噴灑流速能顯著改善晶錠表面的溫度分布，從而減少熱膨脹不均對晶圓表面翹曲的影響。此外，結合下方主輪的熱膨脹效應，綜合考量了整個系統中的熱力學影響，進一步提高了模擬結果的準確性。這些結果有助於理解並提出改善晶圓切割過程中翹曲問題的策略，有效降低材料浪費並減少製程成本。

As the size of the ingot increases, the issue of uneven wafer surfaces after cutting has become increasingly pronounced. This not only raises the difficulty and cost of subsequent semiconductor processes but also leads to material waste and reduces production efficiency. According to observations from this study, wafer warping is primarily caused by two factors: uneven thermal expansion and wire vibration. Uneven thermal expansion occurs due to inconsistent heating and cooling of different depths of the ingot during the cutting process, resulting in varying degrees of thermal expansion across regions, which in turn causes surface height variations on the wafer. Wire vibration can also induce localized surface irregularities during cutting; however, its overall impact is limited and primarily affects localized morphology. This study posits that uneven thermal expansion is the primary reason for overall surface deformation of the wafer, and thus focuses on investigating the thermal expansion behavior under different cutting conditions and its effects on wafer surface quality.
The research employed a model with a diameter of 300 mm and a length of 180 mm, analyzing the temperature distribution during the cutting process using numerical simulation tools and comparing the simulation results with experimental data. Throughout the simulation, the spray flow rate of the slurry was adjusted to study its impact on temperature at various cutting depths. Ultimately, the study demonstrated that altering the slurry spray flow rate significantly improves the temperature distribution on the ingot surface, thereby mitigating the impact of uneven thermal expansion on wafer warping. Additionally, by incorporating the thermal expansion effects of the lower main wheel and considering the thermodynamic influences throughout the entire system, the accuracy of the simulation results was further enhanced. These findings contribute to understanding and developing strategies to address the warping issues encountered during the wafer cutting process, effectively reducing material waste and lowering production costs.

[1] T. Liedke and M. Kuna, "A macroscopic mechanical model of the wire sawing process," International Journal of Machine Tools and Manufacture, vol. 51, no. 9, pp. 711-720, 2011.
[2] H. J. Möller, "Basic mechanisms and models of multi‐wire sawing," Advanced engineering materials, vol. 6, no. 7, pp. 501-513, 2004.
[3] T. Yamada, M. Fukunaga, T. ICHIKAWA, K. FURUNO, K. MAKINO, and A. YOKOYAMA, "Prediction of warping in silicon wafer slicing with wire-saw machine," Theoretical and Applied Mechanics Japan, vol. 51, pp. 251-258, 2002.
[4] S. Bhagavat and I. Kao, "A finite element analysis of temperature variation in silicon wafers during wiresaw slicing," International Journal of Machine Tools and Manufacture, vol. 48, no. 1, pp. 95-106, 2008.
[5] X. Huang, H. Huang, and H. Guo, "Simulation and experimental research on the slicing temperature of the sapphire with diamond wire," International Journal of Computational Methods, vol. 16, no. 04, p. 1843003, 2019.
[6] L. Johnsen, J. E. Olsen, T. Bergstrøm, and K. Gastinger, "Heat transfer during multiwire sawing of silicon wafers," 2012.
[7] M. Bhagavat, V. Prasad, and I. Kao, "Elasto-hydrodynamic interaction in the free abrasive wafer slicing using a wiresaw: modeling and finite element analysis," J. Trib., vol. 122, no. 2, pp. 394-404, 2000.
[8] T. L. Bergman, Fundamentals of heat and mass transfer. John Wiley & Sons, 2011.