雷射切片(laser slicing)為一種精密加工技術，透過雷射聚焦於內部加熱，從而在內部產生熱應力來切片。在半導體晶圓切片應用中，這種小加工損失的技術對於價格高昂的半導體材料便非常適合，但此技術必須精確控制雷射加工過程中所產生的裂紋，以降低後續拋光與研磨產生的材料損耗。而本研究透過實驗數據發現，當裂紋長度足以使相鄰雷射路徑上的裂紋彼此串聯時，晶圓切片成功機率大幅提升。同時，在雷射加工後因加熱效應形成改質區，實驗數據也顯示改質區大小與裂紋長度呈正相關，因此本文分析以改質區大小與雷射參數、材料熱傳性質間的關係為主。
在目前的研究成果中，本研究以四種不同材料性質之N型4H-SiC進行實驗，並根據實驗試片的尺寸建立數值模型，進而推導簡化之無窮域瞬熱解析解，以熱分析的方式計算熱改質區在不同材質的變化，最後據此推估其等效熱傳係數。本研究使用的四種N型4H-SiC預測等效熱傳導係數在250~350 W/m∙K之間，略低於常溫下純SiC的熱傳導係數，與N型4H-SiC在溫度上升時其熱傳導能力降低的實際特性相符。並且藉由這個分析發現，雷射的功率可以影響材料對雷射能量的吸收係數，而相同功率下，熱傳導係數低的N型4H-SiC能夠產生更大的改質區。
在實際應用上，以本研究分析結果，可以測量不同性質之N型4H-SiC電阻率，獲得對應等效熱傳係數，根據所需熱改質區的大小，進一步推估所需的加工功率。
同時，在合作夥伴的研究中，因需要進行二維熱應力的分析，故本研究以二維無窮域解析解為基礎，提供特徵長度與修正係數，協助以二維類比三維的脈衝雷射熱場計算，作為後續切片預測、裂紋長度與雷射參數等一系列熱應力計算分析的基礎。

Laser slicing is a precision processing technique that utilizes focused laser energy to heat material internally and generate thermal stress for controlled material separation. In semiconductor wafer applications, this low-damage method is particularly suitable for high-cost materials. However, the process parameter setting must be carefully tuned so as to control the crack formation and propagation during laser heating, which is critical to minimizing the material loss during subsequent polishing and grinding. Meanwhile, existing experimental data suggest that when the laser-induced cracks are long enough to connect across adjacent laser paths, the success rate of wafer separation increases substantially. Additionally, it is clearly observed that a thermally modified zone (TMZ) forms after laser processing. And the experimental data exhibit a positive correlation between the TMZ size and crack length. Therefore, in this thesis we focus our analysis on how the size of the TMZ is affected by laser parameters and the thermophysical properties of the material being processed.
In particular, the analysis is based on the experiments conducted by our industrial collaborators at ITRI on four N-type 4H-SiC samples with slightly differing thermophysical characteristics. Technically, based on the sample dimensions, a computational model is constructed for the calculation of the thermal conduction characteristics of the samples under laser heating. Meanwhile, an analytic solution also is obtained for the ideal case of impulsive laser heating (taking place in zero time) at a point (of zero size) in a material of infinite extent. As it turns out, for practical laser heating parameter settings, the predictions of the TMZ characteristics by the analytic solution are in satisfactory agreement with the full numerical results, so that we can conveniently uses the analytic solution to estimate the size of the TMZ. Based upon the analytic solution, a systematic methodology then is developed for deducing the actual laser power absorbed by the material and the effective thermal conductivity for each sample. It transpires that the thermal conductivities of the four samples studied here fall within the range of 250-350 W/m-K, which are slightly lower than the thermal conductivity of pure SiC at room temperature. And this trend is consistent with the known behavior of N-type 4H-SiC at elevated temperatures.
Furthermore, to assist a study focused on two-dimensional (2D) thermal stress analysis by our colleagues, in this thesis we also discuss how the characteristic length (i.e., the effective length over which the actual power is uniformly distributed in an equivalent 2D model) can be set such that the 2D temperature distribution can properly represent the actual 3D temperature distribution. This discussion is expected to be useful for analysis of slicing performance, crack lengths, and laser parameter optimization.

[1] P. R. Morris, “A History of the World Semiconductor Industry,” A History of the World Semiconductor Industry, Jan. 1990, doi: 10.1049/PBHT012E.
[2] 藍芳華, “產業經濟統計簡訊113年上市櫃公司及獲利表現.” Accessed: Jul. 05, 2025. [Online]. Available: https://www.moea.gov.tw/Mns/dos/bulletin/Bulletin.aspx?kind=9&html=1&menu_id=18808&bull_id=16610
[3] S. M. Sze and K. K. Ng, Physics of Semiconductor Devices. 2006. doi: 10.1002/0470068329.
[4] “臺灣2024年電動車市場現況及發展趨勢.” Accessed: Jun. 08, 2025. [Online]. Available: https://www.artc.org.tw/tw/knowledge/articles/13790
[5] S. E. Schulz, “Exploring the High-Power Inverter: Reviewing critical design elements for electric vehicle applications,” IEEE Electrification Magazine, vol. 5, no. 1, pp. 28–35, Mar. 2017, doi: 10.1109/MELE.2016.2644281.
[6] 許志雄, “碳化矽材料於功率元件之應用.” [Online]. Available: https://www.google.com/search?sca_esv=62911980d9683afe&q=%E7%A2%B3%E5%8C%96%E7%9F%BD%E6%9D%90%E6%96%99%E6%96%BC%E5%8A%9F%E7%8E%87%E5%85%83%E4%BB%B6%E4%B9%8B%E6%87%89%E7%94%A8(%E8%A8%B1%E5%BF%97%E9%9B%84)-&sa=X&ved=2ahUKEwjNn6-NsN6KAxUxjq8BHRQUAnUQ7xYoAHoECA0QAQ&biw=1920&bih=911&dpr=1
[7] Y. Développement, “Yole Développement - Power SiC 2022 - Product Brochure.”
[8] S. Zhang, Y. Ren, X. Yang, W. Ma, H. Chen, G. Lv, Y. Lei, Y. Zeng, Z. Wang,B. Yu, “Crystal growth principles, methods, properties of silicon carbide and its new process prepared from silicon cutting waste,” Journal of Materials Research and Technology, vol. 34, pp. 2593–2608, Jan. 2025, doi: 10.1016/J.JMRT.2024.12.239.
[9] H. Wu, “Wire sawing technology: A state-of-the-art review,” Precis Eng, vol. 43, pp. 1–9, Jan. 2016, doi: 10.1016/J.PRECISIONENG.2015.08.008.
[10] R. Buchwald, K. Fröhlich, S. Würzner, T. Lehmann, K. Sunder, and H. J. Möller, “Analysis of the sub-surface damage of mc- and Cz-Si wafers sawn with diamond-plated wire,” Energy Procedia, vol. 38, pp. 901–909, 2013, doi: 10.1016/j.egypro.2013.07.363.
[11] P. Wang, P. Ge, Y. Gao, and W. Bi, “Prediction of sawing force for single-crystal silicon carbide with fixed abrasive diamond wire saw,” Mater Sci Semicond Process, vol. 63, pp. 25–32, Jun. 2017, doi: 10.1016/J.MSSP.2017.01.014.
[12] 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 Tribol, vol. 122, no. 2, pp. 394–404, Apr. 2000, doi: 10.1115/1.555375.
[13] C. Chung, G. D. Tsay, and M. H. Tsai, “Distribution of diamond grains in fixed abrasive wire sawing process,” International Journal of Advanced Manufacturing Technology, vol. 73, no. 9–12, pp. 1485–1494, May 2014, doi: 10.1007/S00170-014-5782-Y/METRICS.
[14] T. A. Friedmann, W. C. Sweatt, and B. H. Jared, “Laser wafering for silicon solar.,” Mar. 2011, doi: 10.2172/1011705.
[15] 王俊智, 陳峻明, 黃建融, 林于中, and 陳易呈, “碳化矽（SiC）之雷射切片技術,” 機械工業雜誌, no. 91, pp. 32–38, Feb. 2024. [Online]. Available: https://www.airitilibrary.com/Article/Detail/P20171221002-N202402070013-00007
[16] “SILTECTRATM - Innovative splitting Technologies.”. Available: https://www.infineon.com/cms/en/about-infineon/company/siltectra/
[17] L. Jiang, Zhao S, Han S, Liang H, Du J, Yu H, Lin X, “CW laser-assisted splitting of SiC wafer based on modified layer by picosecond laser,” Opt Laser Technol, vol. 174, p. 110700, Jul. 2024, doi: 10.1016/J.OPTLASTEC.2024.110700.
[18] B. Lv, L. Ye, X. Zhu, Y. Liu, S. Chuai, and Z. Wang, “Ultrasonic-assisted stripping of single-crystal SiC after laser modification,” Ceram Int, vol. 50, no. 22, pp. 48517–48525, Nov. 2024, doi: 10.1016/J.CERAMINT.2024.09.200.
[19] Savas Mitridis, “Physics of Advanced Materials Winter School 2008 Determination of lattice site location of impurities in compound semiconductors, by transmission electron microscopy,” 2008
[20] Gerald Rescher, “Behavior of SiC-MOSFETs under Temperature and Voltage Stress,” eingereicht an der Technischen Universität Wien, 2018. [Online]. Available: https://www.iue.tuwien.ac.at/phd/rescher/index.html
[21] E. Fred Schubert, “Doping in III-V Semiconductors.” Accessed: Jun. 08, 2025. [Online]. Available: https://books.google.com.tw/books?hl=zh-TW&lr=&id=Y6xhCgAAQBAJ&oi=fnd&pg=PR11&dq=how+doped+semiconductor+work+&ots=ryZq1o5WU4&sig=F0Yq2mS0w8G6eMT4E1gNv6IDnxc&redir_esc=y#v=onepage&q&f=false
[22] Q. Chen, Y. Yao, J. Zhang, B. Li, L. Che, X. Zhang, H. Fan, J. Tian, Y. Peng, X. Xie, B. Zhang, R. Wang, “Effect of nitrogen doping concentration on 4H-SiC laser slicing,” Journal of the American Ceramic Society, vol. 108, no. 8, p. e20555, Aug. 2025, doi: 10.1111/JACE.20555;JOURNAL:JOURNAL:15512916;WGROUP:STRING:PUBLICATION.
[23] A. K. Nath, “High Power Lasers in Material Processing Applications: An Overview of Recent Developments,” Springer Series in Materials Science, vol. 161, pp. 69–111, 2013, doi: 10.1007/978-3-642-28359-8_2/FIGURES/31.
[24] R. L.-C. Bulletin and undefined 1969, “Controlled separation of brittle materials using a laser,” American Ceramic Society Bulletin, pp. 850–854, 1969. [Online]. Available: https://cir.nii.ac.jp/crid/1570854174493273472
[25] K. F.-P. of the 4th International. C. on and undefined 2006, “The mechanism of semiconductor wafer dicing by stealth dicing technology,” cir.nii.ac.jp. [Online]. Available: https://cir.nii.ac.jp/crid/1570009750625390592
[26] E. Ohmura, K. Fukumitsu, M. Kumagai, and H. Morita, “ナノ秒レーザによる単結晶シリコンの内部改質層形成機構の解析,” 日本機械学会論文集 C編, vol. 74, no. 738, pp. 446–452, Feb. 2008, doi: 10.1299/KIKAIC.74.446.
[27] T. A. Friedmann, W. C. Sweatt, and B. H. Jared, “Laser wafering for silicon solar.,” Mar. 2011, doi: 10.2172/1011705.
[28] R. A. Richter et al., “Sub-surface modifications in silicon with ultra-short pulsed lasers above 2 µm,” JOSA B, Vol. 37, Issue 9, pp. 2543-2556, vol. 37, no. 9, pp. 2543–2556, Sep. 2020, doi: 10.1364/JOSAB.396074.
[29] 洋平山田, 知陽池田, and 順一池野, “SiCの精密レーザスライシング 第１報：カーフロスを考慮したスライシング法の検討,” 砥粒加工学会誌, vol. 64, no. 12, pp. 635–642, Dec. 2020, doi: 10.11420/JSAT.64.635.
[30] 洋平山田, 知陽池田, 伶美小松崎, and 順一池野, “SiCの精密レーザスライシング 第2報：走査方向とへき開伸展・連結の関係性,” 砥粒加工学会誌, vol. 65, no. 10, pp. 549–555, Oct. 2021, doi: 10.11420/JSAT.65.549.
[31] 洋平山田, 伶美小松崎, 拓菊池, and 順一池野, “SiCの精密レーザスライシング 第3報：改質とへき開伸展のパルス幅依存性,” 砥粒加工学会誌, vol. 67, no. 7, pp. 401–406, Jul. 2023, doi: 10.11420/JSAT.67.401.
[32] 山田 洋平小松崎 伶美, 菊池 拓, 池野 順一, “SiCの精密レーザスライシング(第4報)短パルスレーザによる高速・高安定加工の検討,” Abrasive technology : 砥粒加工学会誌 : journal of the Japan Society for Abrasive Technology, vol. 67, no. 11, pp. 600–605, 2023, Accessed: Jun. 11, 2025. [Online]. Available: https://cir.nii.ac.jp/crid/1520861074055147776
[33] 蘇志宏, “水輔助雷射加工之熱流分析,” 國立成功大學, 2006.
[34] 陳光迪, “透過暫態溫度場變化特性探討超薄玻璃雷射劈裂機制,” 國立成功大學, 2013.
[35] 林上棋, “雷射玻璃裂片製程參數及其熱場特性之關聯性研究,” 國立成功大學, 2017.
[36] 鄭兆廷, “複合材料雷射熱黏合製程之建模與分析,” 國立成功大學, 2017.
[37] 黃鈺庭, “雷射切割玻璃之熱應力分析,” 國立成功大學, 2021.
[38] R. Zhang, C. Huang, J. Wang, H. Zhu, P. Yao, and S. Feng, “Micromachining of 4H-SiC using femtosecond laser,” Ceram Int, vol. 44, no. 15, pp. 17775–17783, Oct. 2018, doi: 10.1016/J.CERAMINT.2018.06.245.
[39] “Talon® Q-Switched Laser.” Accessed: Jan. 06, 2025. [Online]. Available: https://www.spectra-physics.com/en/f/talon-q-switched-laser
[40] X. Liu, J. Zhang, B. Xu, Y. Lu, Y. Zhang, R. Wang, D. Yang, X. Pi, “Deformation of 4H-SiC: The role of dopants,” Appl Phys Lett, vol. 120, no. 5, p. 52105, Jan. 2022, doi: 10.1063/5.0083882/2832932.
[41] B. Adelmann and R. Hellmann, “SiC absorption of near-infrared laser radiation at high temperatures,” Appl Phys A Mater Sci Process, vol. 122, no. 7, pp. 1–7, Jul. 2016, doi: 10.1007/S00339-016-0173-X/FIGURES/5.
[42] N. H. Protik, A. Katre, L. Lindsay, J. Carrete, N. Mingo, and D. Broido, “Phonon thermal transport in 2H, 4H and 6H silicon carbide from first principles,” Materials Today Physics, vol. 1, pp. 31–38, Jun. 2017, doi: 10.1016/J.MTPHYS.2017.05.004.
[43] X. Qian, P. Jiang, and R. Yang, “Anisotropic thermal conductivity of 4H and 6H silicon carbide measured using time-domain thermoreflectance,” Materials Today Physics, vol. 3, pp. 70–75, Dec. 2017, doi: 10.1016/J.MTPHYS.2017.12.005