Effect of Heat Shield Structure on the Distribution of Oxygen Content in 200 mm Semiconductor-Grade Czochralski Monocrystalline Silicon

Abstract

Abstract: Semiconductor-grade monocrystalline silicon is the basic material for the integrated circuit industry and its quality determines the performance of chips. The distribution of oxygen content in Czochralski (Cz) silicon crystals has an important impact on the quality of silicon wafers. The oxygen content distribution during crystal growth can be effectively controlled by optimizing the heat shield structure of the furnace, but it is difficult to investigate the intrinsic mechanism through experiments. In this study, effect of the structure of heat shield on the distribution of oxygen content in 200 mm semiconductor-grade Cz monocrystalline silicon was investigated by ANSYS finite element analysis. Single-section and two-section heat shield structures are widely used in commercial furnace, by comparison, the distribution of temperature and flow fields, the temperature gradient at the solid-liquid interface and the radial oxygen content distribution for different stages of body growth (300, 800, 1 000 mm) were analyzed. The simulation results demonstrate that the temperature field uniformity of the single-section heat shield structure is better than that of the two-section heat shield structure, the temperature gradient at the solid-liquid interface in the former is smaller. Also, the low argon flow rate is favorale to the volatilization of SiO gas, and weakening the shear convection of the melt, leading to an inhibition of diffusion movement of oxygen from melt to crystal. Therefore, the radial oxygen content distribution at the solid-liquid interface is more uniform and the oxygen content in the crystal is lower under the condition of the single-section heat shield structure than that of the two-section heat shield structure.

Key words: semiconductor-grade monocrystalline silicon, oxygen content, finite element analysis, heat shield structure, temperature field, flow field

CLC Number:

RUI Yang, WANG Zhongbao, SHENG Wang, NI Haoran, XIONG Huan, ZOU Qipeng, CHEN Weinan, HUANG Liuqing, LUO Xuetao. Effect of Heat Shield Structure on the Distribution of Oxygen Content in 200 mm Semiconductor-Grade Czochralski Monocrystalline Silicon[J]. Journal of Synthetic Crystals, 2023, 52(6): 1110-1119.

References

[1] KAKIMOTO K, GAO B, LIU X, et al. Growth of semiconductor silicon crystals[J]. Progress in Crystal Growth and Characterization of Materials, 2016, 62(2): 273-285.
[2] 刘立军. 晶体生长数值模拟领域的若干研究进展[J]. 中国材料进展, 2019, 38(5): 523-527.
LIU L J. Some research progress in the field of numerical simulation of crystal growth[J]. Materials China, 2019, 38(5): 523-527 (in Chinese).
[3] 张西亚, 高德东, 王珊, 等. 热屏下降式单晶炉设计与研究[J]. 人工晶体学报, 2021, 50(6): 987-995.
ZHANG X Y, GAO D D, WANG S, et al. Design and research on descended heat shield of the single crystal furnace[J]. Journal of Synthetic Crystals, 2021, 50(6): 987-995 (in Chinese).
[4] SONG D W, LEE S H, MUN Y H, et al. Oxygen content increasing mechanism in Czochralski (CZ) silicon crystals doped with heavy antimony under a double-typed heat shield[J]. Journal of Crystal Growth, 2011, 325(1): 27-31.
[5] 滕冉, 常青, 吴志强, 等. 热屏结构对大直径单晶硅生长影响的数值分析[J]. 人工晶体学报, 2014, 43(3): 508-512.
TENG R, CHANG Q, WU Z Q, et al. Numerical analysis of the effect of heat shield structure on growth of large diameter monocrystalline silicon[J]. Journal of Synthetic Crystals, 2014, 43(3): 508-512 (in Chinese).
[6] KUMAR M A, SRINIVASAN M, RAMASAMY P. Reduction of carbon and oxygen impurities in mc-silicon ingot using molybdenum gas shield in directional solidification process[J]. Silicon, 2021, 13(12): 4535-4544.
[7] ZHANG J, LIU D, ZHAO Y, et al. Impact of heat shield structure in the growth process of Czochralski silicon derived from numerical simulation[J]. Chinese Journal of Mechanical Engineering, 2014, 27(3): 504-510.
[8] 李进, 张洪岩, 高忙忙, 等. 氩气流速对400 mm大直径磁场直拉单晶硅固液界面、热应力及氧含量的影响[J]. 人工晶体学报, 2014, 43(5): 1193-1198+1211.
LI J, ZHANG H Y, GAO M M, et al. Influence of argon flow rate on the solid/liquid interface, thermal stress and oxygen concentration in the 400 mm CZ silicon with a magnetic field[J]. Journal of Synthetic Crystals, 2014, 43(5): 1193-1198+1211 (in Chinese).
[9] JANA S, DOST S, KUMAR V, et al. A numerical simulation study for the Czochralski growth process of Si under magnetic field[J]. International Journal of Engineering Science, 2006, 44(8/9): 554-573.
[10] MUKAIYAMA Y, SUEOKA K, MAEDA S, et al. Numerical analysis of effect of thermal stress depending on pulling rate on behavior of intrinsic point defects in large-diameter Si crystal grown by Czochralski method[J]. Journal of Crystal Growth, 2020, 531: 125334.
[11] 谭建国. 使用ANSYS6.0进行有限元分析[M]. 北京: 北京大学出版社, 2002.
TAN J G. Finite element analysis using ANSYS 6.0[M]. Beijing: Peking University Press, 2002 (in Chinese).
[12] 巴特 K J, 威尔逊 E L. 有限元分析中的数值方法[M]. 林公豫, 罗恩, 译. 北京: 科学出版社, 1985.
BATHE K J, WILSON E L. Numerical method in finite element analysis[M]. LIN G Y, LUO E, Transl. Beijing: Science Press, 1985 (in Chinese).
[13] 帕斯卡S V. 传热与流体流动的数值计算[M]. 张政, 译. 北京: 科学出版社, 1984.
PATANKAR S V. Numerical Heat Transfer and Fluid Flow[M]. ZHANG Z, Transl. Beijing: Science Press, 1984 (in Chinese).
[14] 唐兴伦, 范群波, 张朝辉,等. ANSYS工程应用教程(热与电磁篇)[M]. 北京: 中国铁道出版社, 2003.
TANG X L, FAN Q B, ZHANG C H, et al. Application of ANSYS on the engineering of heat and magnetism[M]. Beijing: China Railway Publishing House, 2003 (in Chinese).
[15] 俞昌铭. 热传导及其数值分析[M]. 北京: 清华大学出版社, 1981.
YU C M. Heat transfer and numerical analysis[M]. Beijing: Tsinghua University Press,1981 (in Chinese).
[16] 孔祥谦, 王传溥. 有限元在传热学中的应用[M]. 北京: 科学出版社, 1981.
KONG X Q, WANG C P. Application of finite element in heat transfer[M]. Beijing: Science Press, 1981 (in Chinese).
[17] KALAEV V. Computer modeling of HMCz Si growth[J]. Journal of Crystal Growth, 2020, 532: 125413.
[18] SMIRNOV A D, KALAEV V V. Development of oxygen transport model in Czochralski growth of silicon crystals[J]. Journal of Crystal Growth, 2008, 310(12): 2970-2976.
[19] 林明献. 硅晶圆半导体材料技术[M]. 全华图书股份有限公司, 2020.
LIN M X. Silicon wafer semiconductor[M]. Chuan Hwa Book Co., Ltd., 2020 (in Chinese).
[20] DING J L, LI Y Q, LIU L J. Effect of cusp magnetic field on the turbulent melt flow and crystal/melt interface during large-size Czochralski silicon crystal growth[J]. International Journal of Thermal Sciences, 2021, 170: 107137.
[21] JOMÂA M, M′HAMDI M, HU Y, et al. Numerical analysis of oxygen control during growth of Czochralski silicon single crystals[C]//2014 IEEE 40th Photovoltaic Specialist Conference (PVSC). June 8-13, 2014, Denver, CO, USA. IEEE, 2014: 3521-3525.
[22] CHEN J C, CHIANG P Y, NGUYEN T H T, et al. Numerical simulation of the oxygen concentration distribution in silicon melt for different crystal lengths during Czochralski growth with a transverse magnetic field[J]. Journal of Crystal Growth, 2016, 452: 6-11.
[23] LIU X, HARADA H, MIYAMURA Y, et al. Transient global modeling for the pulling process of Czochralski silicon crystal growth. II. Investigation on segregation of oxygen and carbon[J]. Journal of Crystal Growth, 2019, 532: 125404.
[24] GENG X, WU X B, GUO Z Y. Numerical simulation of combined flow in Czochralski crystal growth [J]. Journal of Crystal Growth, 1997, 179(1/2): 309-319.
[25] TENG Y Y, CHEN J C, HUANG C C, et al. Numerical investigation of the effect of heat shield shape on the oxygen impurity distribution at the crystal-melt interface during the process of Czochralski silicon crystal growth [J]. Journal of Crystal Growth, 2012, 352(1): 167-172.