掺杂对GaN晶体力学性能影响的研究

人工晶体学报 ›› 2023, Vol. 52 ›› Issue (2): 229-234.

掺杂对GaN晶体力学性能影响的研究

王海笑^1,2, 李腾坤¹, 夏政辉^1,2, 陈科蓓¹, 张育民^1,3, 王鲁华¹, 高晓东¹, 任国强¹, 徐科^1,3,4

1.中国科学院苏州纳米技术与纳米仿生研究所,苏州 215123;
2.中国科学技术大学纳米科学与技术学院,合肥 230026;
3.苏州纳维科技有限公司,苏州 215123;
4.江苏第三代半导体研究院,苏州 215000

收稿日期:2022-10-31 出版日期:2023-02-15 发布日期:2023-03-08
通信作者: 任国强,博士,研究员。E-mail:gqren2008@sinano.ac.cn徐科,博士,研究员。E-mail:kxu2006@sinano.ac.cn
作者简介:王海笑(1996—),男,安徽省人,硕士研究生。E-mail:hxwang2020@sinano.ac.cn
基金资助:
国家重点研发计划(2022YFB3605202,2021YFB3602000);江苏省重点研发计划(BE2021008);国家自然科学基金(62074157, 62104246);中科院关键技术人才计划(2021000052)

Effect of Doping on the Mechanical Properties of GaN Crystals

WANG Haixiao^1,2, LI Tengkun¹, XIA Zhenghui^1,2, CHEN Kebei¹, ZHANG Yumin^1,3, WANG Luhua¹, GAO Xiaodong¹, REN Guoqiang¹, XU Ke^1,3,4

1. Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China;
2. School of Nano Science and Technology Institute, University of Science and Technology of China, Hefei 230026, China;
3. Suzhou Nanowin Science and Technology Co., Ltd., Suzhou 215123, China;
4. Jiangsu Institute of Advanced Semiconductors, Ltd., Suzhou 215000, China

Received:2022-10-31 Online:2023-02-15 Published:2023-03-08

摘要/Abstract

摘要： 对GaN单晶力学性能的研究有助于解决其在生长、加工和器件应用中的开裂问题。本文围绕掺杂对GaN单晶力学性能的影响,通过纳米压痕法测试了不同掺杂类型(非掺、Si掺和Fe掺)GaN单晶的弹性模量和硬度,测试结果表明掺杂对GaN单晶的硬度有重要影响。Si掺、Fe掺GaN较非掺样品硬度有所提升,用重掺杂的氨热GaN单晶作为对照,也证明了这一结论。通过高分辨X射线衍射分析和原子力显微镜表征实验发现,晶体结晶质量、接触面积等因素对GaN单晶硬度的影响较小。对GaN表面纳米压痕滑移带长度和晶体晶格常数进行测试,结果表明,掺杂影响GaN单晶硬度的主要原因是缺陷对GaN位错增殖、滑移的阻碍作用和掺杂引起的GaN晶格常数的变化。

关键词: GaN单晶, 弹性模量, 硬度, 纳米压痕, 氨热法, 掺杂

Abstract: The study of the mechanical properties of GaN single crystals can help to solve the problem of cracking in the growth, processing and device applications. In this paper, the elastic modulus and hardness of GaN single crystals with different doping types (undoped, Si-doped and Fe-doped) were tested by nanoindentation method to explore the effect of doping on the mechanical properties of GaN single crystals. The test results show that doping has an important effect on the hardness of GaN single crystals. The hardness of Si-doped and Fe-doped GaN samples are higher than that of undoped sample, this conclusion was also proved by the comparison of heavily doped ammonothermal GaN single crystals. Through high-resolution X-ray diffraction analysis and atomic force microscopy characterization, it is found that factors such as crystal crystalline quality and contact area have less influence on the hardness of GaN single crystals. The nanoindentation slip band length and crystal lattice constant of GaN surface were measured. The results show that, the main reasons for doping affecting the hardness of GaN single crystals are the hindering effect of defects on GaN dislocation multiplication and slip, and the change of GaN lattice constant caused by doping.

Key words: GaN single crystal, elastic modulus, hardness, nanoindentation, ammonothermal method, doping

中图分类号:

王海笑, 李腾坤, 夏政辉, 陈科蓓, 张育民, 王鲁华, 高晓东, 任国强, 徐科. 掺杂对GaN晶体力学性能影响的研究[J]. 人工晶体学报, 2023, 52(2): 229-234.

WANG Haixiao, LI Tengkun, XIA Zhenghui, CHEN Kebei, ZHANG Yumin, WANG Luhua, GAO Xiaodong, REN Guoqiang, XU Ke. Effect of Doping on the Mechanical Properties of GaN Crystals[J]. JOURNAL OF SYNTHETIC CRYSTALS, 2023, 52(2): 229-234.

参考文献

[1] PEARTON S J, REN F, ZHANG A P, et al. Fabrication and performance of GaN electronic devices[J]. Materials Science and Engineering: R: Reports, 2000, 30(3/4/5/6): 55-212.
[2] EFTHYMIOU L, LONGOBARDI G, CAMUSO G, et al. On the physical operation and optimization of the p-GaN gate in normally-off GaN HEMT devices[J]. Applied Physics Letters, 2017, 110(12): 123502.
[3] ANDERSON T J, CHOWDHURY S, AKTAS O, et al. GaN power devices-current status and future directions[J]. The Electrochemical Society Interface, 2018, 27(4): 43-47.
[4] KRUSZEWSKI P, PRYSTAWKO P, KASALYNAS I, et al. AlGaN/GaN HEMT structures on ammono bulk GaN substrate[J]. Semiconductor Science and Technology, 2014, 29(7): 075004.
[5] WOJTASIAK W, GÓRALCZYK M, GRYGLEWSKI D, et al. AlGaN/GaN high electron mobility transistors on semi-insulating ammono-GaN substrates with regrown ohmic contacts[J]. Micromachines, 2018, 9(11): 546.
[6] LI T K, REN G Q, SU X J, et al. Growth behavior of ammonothermal GaN crystals grown on non-polar and semi-polar HVPE GaN seeds[J]. CrystEngComm, 2019, 21(33): 4874-4879.
[7] LI T K, REN G Q, YAO J J, et al. Study of stress in ammonothermal non-polar and semi-polar GaN crystal grown on HVPE GaN seeds[J]. Journal of Crystal Growth, 2020, 532: 125423.
[8] CHENG Y T, CAI D J, WANG H, et al. Anisotropic fracture toughness of bulk GaN[J]. Physica Status Solidi (b), 2018, 255(5): 1700515.
[9] DRORY M D, AGER J W, SUSKI T, et al. Hardness and fracture toughness of bulk single crystal gallium nitride[J]. Applied Physics Letters, 1996, 69(26): 4044-4046.
[10] NAKAMURA S, SENOH M, NAGAHAMA S I, et al. InGaN multi-quantum-well-structure laser diodes with cleaved mirror cavity facets[J]. Japanese Journal of Applied Physics, 1996, 35(2B): L217.
[11] FUJIKANE M, INOUE A, YOKOGAWA T, et al. Mechanical properties characterization of c-plane (0001) and m-plane (10-10) GaN by nanoindentation examination[J]. Physica Status Solidi C, 2010, 7(7/8): 1798-1800.
[12] KAVOURAS P, RATSCHINSKI I, DIMITRAKOPULOS G P, et al. Deformation and fracture in (0001) and (10-10) GaN single crystals[J]. Materials Science and Technology, 2018, 34(13): 1531-1538.
[13] HUANG J, XU K, FAN Y M, et al. Nanoscale anisotropic plastic deformation in single crystal GaN[J]. Nanoscale Research Letters, 2012, 7(1): 150.
[14] OLIVER W C, PHARR G M. An improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments[J]. Journal of Materials Research, 1992, 7(6): 1564-1583.
[15] OLIVER W C, PHARR G M. Measurement of hardness and elastic modulus by instrumented indentation: advances in understanding and refinements to methodology[J]. Journal of Materials Research, 2004, 19(1): 3.
[16] MORAM M A, VICKERS M E. X-ray diffraction of Ⅲ-nitrides[J]. Reports on Progress in Physics, 2009, 72(3): 036502.
[17] BAXEVANI E A, GIANNAKOPOULOS A E. The modified Rockwell test: a new probe for mechanical properties of metals[J]. Experimental Mechanics, 2009, 49(3): 371-382.
[18] TSUI T Y, OLIVER W C, PHARR G M. Influences of stress on the measurement of mechanical properties using nanoindentation: part I. Experimental studies in an aluminum alloy[J]. Journal of Materials Research, 1996, 11(3): 752-759.
[19] BOLSHAKOV A, OLIVER W C, PHARR G M. Influences of stress on the measurement of mechanical properties using nanoindentation: part Ⅱ. Finite element simulations[J]. Journal of Materials Research, 1996, 11(3): 760-768.
[20] CARLSSON S, LARSSON P L. On the determination of residual stress and strain fields by sharp indentation testing[J]. Acta Materialia, 2001, 49(12): 2193-2203.
[21] LARSSON P L. On the invariance of hardness at vickers indentation of pre-stressed materials[J]. Metals, 2017, 7(7): 260.
[22] HUANG J, XU K, GONG X J, et al. Dislocation cross-slip in GaN single crystals under nanoindentation[J]. Applied Physics Letters, 2011, 98(22): 221906.
[23] JIAN S. Mechanical deformation induced in Si and GaN under berkovich nanoindentation[J]. Nanoscale Research Letters, 2007, 3(1): 6-13.
[24] FUJIKURA H, OSHIMA Y, MEGRO T, et al. Hardness control for improvement of dislocation reduction in HVPE-grown freestanding GaN substrates[J]. Journal of Crystal Growth, 2012, 350(1): 38-43.
[25] EVTIMOVA S, ARNAUDOV B, PASKOVA T, et al. Effect of carrier concentration on the microhardness of GaN layers[J]. Journal of Materials Science: Materials in Electronics, 2003, 14(10): 771-772.