8英寸SiC晶圆制备与外延应用

摘要/Abstract

摘要： 碳化硅(SiC)是制作高温、高频、大功率电子器件的理想电子材料之一,近20年来随着SiC材料加工技术的不断提升,其应用领域不断扩大。目前SiC芯片的制备仍然以6英寸(1英寸=25.4 mm)晶圆为主,但是行业龙头企业已经开始研发基于8英寸SiC晶圆的下一代器件和芯片。本研究联合国内SiC产业链上、下游龙头企业,推进8英寸SiC芯片国产研发,尤其是关键的晶圆制备和外延应用环节。本文采用扩径生长法制备了8英寸导电型4H-SiC衬底晶圆,其平均基平面位错(BPD)密度低至251 cm^-2,平均螺位错(TSD)密度小于1 cm^-2,实现了近“零TSD”和低BPD密度的8英寸导电型4H-SiC衬底晶圆的制备,可以满足生产需要。采用国产8英寸外延设备和开发工艺包,实现了速率为68.66 μm/h的快速外延生长,厚度不均匀性为0.89%,掺杂不均匀性为2.05%,这两个指标已经达到了优良6英寸外延膜的水平,完全可以满足生产需要。与国外已发布的8英寸外延结果对比,厚度和掺杂均匀性均优于国外数据,而缺陷密度只有国外数据的1/4。本文设计和实施了多片重复性试验,验证了8英寸外延的稳定性。

关键词: 碳化硅, 8英寸, 晶圆, 外延, 缺陷密度, 掺杂均匀性

Abstract: Silicon carbide (SiC) is one of the superior materials used in the manufacture of electronic components designed to work at high temperatures, high frequencies and high-power. In the past two decades, the application of SiC materials has been expanding as a result of much improved production and processing techniques. Although most SiC chips are still mainly made from 6 inch (1 inch=25.4 mm) wafers, leading manufacturers have begun developing next-generation parts and chips based upon 8 inch SiC wafers. This study collaborates with leading enterprises in the upstream and downstream of the domestic silicon carbide industry chain in order to facilitate domestic production of 8 inch SiC chips, with the focus being wafer preparation and epitaxial growth. In this work, 8 inch conductive 4H-SiC substrate wafer was prepared by diameter expansion growth, with low average base plane dislocation (BPD) density (251 cm^-2) and virtually ‘zero threading screw dislocation (TSD)’ density (<1 cm^-2) that meet the production requirements. Based on these 8 inch substrates, we achieve fast epitaxial growth (68.66 μm/h) with domestically produced 8 inch epitaxy equipment and processing packages. The thickness uniformity of the resultant wafers is 0.89% and the doping uniformity is 2.05%. These parameters, as well as the defect density, are on par with those of high-quality 6-inch wafers, fully meeting production requirements. The 8 inch wafers prepared in this paper are better than those described in international publications in terms of thickness and doping uniformity. The defect density is only 1/4 of international data. In this paper, multi-wafer repetative text was designed and executed, to verify the stability of 8 inch epitaxy.

Key words: silicon carbide, 8 inch, wafer, epitaxy, defect density, doping uniformity

中图分类号:

TN05
TQ050.5

韩景瑞, 李锡光, 李咏梅, 王垚浩, 张清纯, 李达, 施建新, 闫鸿磊, 韩跃斌, 丁雄杰. 8英寸SiC晶圆制备与外延应用[J]. 人工晶体学报, 2024, 53(10): 1712-1719.

HAN Jingrui, LI Xiguang, LI Yongmei, WANG Yaohao, ZHANG Qingchun, LI Da, SHI Jianxin, YAN Honglei, HAN Yuebin, TING Hungkit. Preparation and Epitaxy Application of 8 Inch SiC Wafers[J]. JOURNAL OF SYNTHETIC CRYSTALS, 2024, 53(10): 1712-1719.

参考文献

[1] CASADY J, JOHNSON R. Status of silicon carbide (SiC) as a wide-bandgap semiconductor for high-temperature applications: a review[J]. Solid State Electron, 1996, 39(10): 1409-1422.
[2] MORKOÇ H, STRITE S, GAO G B, et al. Large-band-gap SiC, III-V nitride, and II-VI ZnSe-based semiconductor device technologies[J]. Journal of Applied Physics, 1994, 76(3): 1363-1398.
[3] EDDY C R Jr, GASKILL D K. Silicon carbide as a platform for power electronics[J]. Science, 2009, 324(5933): 1398-1400.
[4] LEE T H, BHUNIA S, MEHREGANY M. Electromechanical computing at 500 ℃ with silicon carbide[J]. Science, 2010, 329(5997): 1316-1318.
[5] 韩跃斌, 蒲勇, 施建新. 化学气相沉积法碳化硅外延设备技术进展[J]. 人工晶体学报, 2022, 51(7): 1300-1308.
HAN Y B, PU Y, SHI J X. Advances in chemical vapor deposition equipment used for SiC epitaxy[J]. Journal of Synthetic Crystals, 2022, 51(7): 1300-1308 (in Chinese).
[6] WELLMANN P J. Review of SiC crystal growth technology[J]. Semiconductor Science and Technology, 2018, 33(10): 103001.
[7] SHE X, HUANG A Q, LUCÍA Ó, et al. Review of silicon carbide power devices and their applications[J]. IEEE Transactions on Industrial Electronics, 2017, 64(10): 8193-8205.
[8] Semiconductor engineering. SiC demand growing faster than supply[EB/OL].(2019-05-23)[2024-06-01]. https://semiengineering.com/sic-demand-growing-faster-than-supply/.
[9] Compound semiconductor. Infineon tackles SiC supply shortages[EB/OL].(2018-12-19)[2024-06-01]. https://compoundsemiconductor.net/article/106023/Infineon_Tackles_SiC_Supply_Shortages%7BfeatureExtra%7D/.
[10] MUSOLINO M, XU X P, WANG H, et al. Paving the way toward the world’s first 200 mm SiC pilot line[J]. Materials Science in Semiconductor Processing, 2021, 135: 106088.
[11] Semiconductor TODAY. II-VI Advanced materials demos first 200 mm SiC wafer[EB/OL].(2015-07-17)[2024-06-01].http://www.semiconductor-today.com/news_items/2015/jul/iivi_170715.shtml.
[12] Wolfspeed, Inc. Wolfspeed opens the world’s largest 200 mm silicon carbide fab enabling highly anticipated device production[EB/OL].(2022-04-22)[2024-06-01]. https://www.wolfspeed.com/company/news-events/news/wolfspeed-opens-the-worlds-largest-200mm-silicon-carbide-fab-enabling-highly-anticipated-device-production/.
[13] REACTION-KDT JU. Reaction project introduction[EB/OL][2024-06-01]. http://www.reaction-ecsel.eu/.
[14] CRIPPA D, AZADMAND M, MAUCERI M, et al. Opening through 200 mm silicon carbide epitaxy[J]. Materials Science Forum, 2022, 1062: 146-151.
[15] 艾邦半导体网. 10余家企业参与,5年内碳化硅(SiC)将全面入8英寸时代[EB/OL].(2023-09-13)[2024-06-01]. https://www.ab-sm.com/a/39340.
AiBang Semiconductor Network. With more than 10 companies participating, will fully enter the 8-inch era of silicon carbide (SiC) within 5 years[EB/OL]. (2023-09-13)[2024-06-01]. https://www.ab-sm.com/a/39340 (in Chinese).
[16] 娄艳芳, 巩拓谌, 张文, 等. 8英寸导电型4H-SiC单晶衬底制备与表征[J]. 人工晶体学报, 2022, 51(12): 2131-2136.
LOU Y F, GONG T C, ZHANG W, et al. Fabrication and characterizations of 8-inch n type 4H-SiC single crystal substrate[J]. Journal of Synthetic Crystals, 2022, 51(12): 2131-2136 (in Chinese).
[17] 山东大学. 徐现刚教授团队在8英寸导电型碳化硅衬底制备技术领域取得重要突破[EB/OL].(2022-09-26)[2024-06-01]. https://dpt.sdu.edu.cn/info/1037/2081.htm?eqid=e15ca135000614b300000004645369fb.
Shandong University. Professor Xu Xingang′s team has made significant breakthroughs in the field of 8-inch conductive silicon carbide substrate preparation technology[EB/OL].(2022-09-26)[2024-06-01]. https://dpt.sdu.edu.cn/info/1037/2081.htm?eqid=e15ca135000614b300000004645369fb (in Chinese).
[18] 深圳市电子商会. 即将量产8英寸碳化硅衬底,天科合达的技术有多拔尖？碳化硅成为最热赛道之一[EB/OL].(2022-11-25)[2024-06-01]. https://wap.seccw.com/Document/detail/id/16618.html.
Shenzhen Electronic Chamber of Commerce. How advanced is Tianke Heda′s technology in the upcoming mass production of 8-inch silicon carbide substrates? Silicon carbide becomes one of the hottest tracks[EB/OL].(2022-11-25)[2024-06-01]. https://wap.seccw.com/Document/detail/id/16618.html (in Chinese).
[19] ZHANG S T, FU G Q, CAI H D, et al. Design and optimization of thermal field for PVT method 8-inch SiC crystal growth[J]. Materials, 2023, 16(2): 767.
[20] XU B J, HAN X F, XU S C, et al. Optimization of the thermal field of 8-inch SiC crystal growth by PVT method with ‘3 separation heater method’[J]. Journal of Crystal Growth, 2023, 614: 127238.
[21] 厦门大学物理学系. 国内首家！厦门大学实现8英寸碳化硅外延生长[EB/OL].[2024-06-01].https://phys.xmu.edu.cn/info/1023/6156.htm.
Department of Physics, Xiamen University. The first in China! Xiamen University achieves 8-inch silicon carbide epitaxial growth[EB/OL].[2024-06-01].https://phys.xmu.edu.cn/info/1023/6156.htm (in Chinese).
[22] 杨祥龙, 陈秀芳, 谢雪健, 等. 8英寸导电型4H-SiC单晶的生长[J]. 人工晶体学报, 2022, 51(9): 1745-1748.
YANG X L, CHEN X F, XIE X J, et al. Growth of 8 inch conductivity type 4 H-SiC single crystals[J]. Journal of Synthetic Crystals, 2022, 51(9): 1745-1748 (in Chinese).
[23] 熊希希, 杨祥龙, 陈秀芳, 等. 低位错密度8英寸导电型碳化硅单晶衬底制备[J]. 无机材料学报, 2023, 38(11): 1371-1372.
XIONG X X, YANG X L, CHEN X F, et al. Fabrication of 8-inch N-type 4H-SiC single crystal substrate with low dislocation density[J]. Journal of Inorganic Materials, 2023, 38(11): 1371-1372 (in Chinese).
[24] 第三代半导体产业技术创新战略联盟标准化委员会. 碳化硅晶片位错密度检测方法KOH腐蚀结合图像识别法: T/CASA 013—2021[S]. 2021. http://www.casa-china.cn/uploads/soft/211101/12_1417272332.pdf.
CASAS. Measuring method for testing the density of dislocation in SiC crystal combined KOH etching and image recognition methods: T/CASA 013—2021[S]. 2021. http://www.casa-china.cn/uploads/soft/211101/12_1417272332.pdf (in Chinese).
[25] ZHANG Z, SUDARSHAN T S. Evolution of basal plane dislocations during 4H-silicon carbide homoepitaxy[J]. Applied Physics Letters, 2005, 87(16): 161917.
[26] 韩跃斌, 蒲勇, 施建新, 等. 高速旋转垂直热壁CVD外延生长n型4H-SiC膜的研究[J]. 人工晶体学报, 2023, 52(5): 918-924.
HAN Y B, PU Y, SHI J X, et al. Epitaxial growth study of n-type 4H-SiC films by high-speed wafer rotation vertical hot-wall CVD equipment[J]. Journal of Synthetic Crystals, 2023, 52(5): 918-924 (in Chinese).