Abstract
The strain relaxation mechanism in III-N materials is occurred through the motion of dislocations that generated at III-N/Si interface as a result of large mismatch in lattice and thermal expansion coefficients. As a result of the large lattice mismatch between different layers, the upper layer gets strained and with thicker layers, the strain energy increases until a thickness limit called the critical material thickness. Most of such dislocations (threading dislocations ) penetrate the top surface forming V-pits defects at the top surface that relax the material. These V-pits directly affect the device efficiency, performance, and reliability. Therefore, in this paper, a thermodynamics-based model will be used to study the V-pits formulation and growth in the III-N (especially, InGaN-based materials). In this model, three types of energies are used under a balanced system to model the V-pit formation and growth. These energies are the strain energy in the InGaN epilayer, the destruction energy as a result of dislocation to form the V-pit, and the strain energy of the V-pits facets that generated during the facet nucleation .
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Similar content being viewed by others
References
Cheng J, Yang X, Sang L, Guo L, Zhang J, Wang J, He C, Zhang L, Wang M, Xu F, Tang N (2016) Growth of high quality and uniformity AlGaN/GaN heterostructures on Si substrates using a single AlGaN layer with low Al composition. Sci Rep 6:23020
Kukushkin SA, Osipov AV, Bessolov VN, Medvedev BK, Nevolin VK, Tcarik KA (2008) Substrates for epitaxy of gallium nitride: new materials and techniques. Rev Adv Mater Sci 17(1/2):1–32
Khafagy KH, Hatem TM, Bedair SM (2018) Impact of embedded voids on thin-films with high thermal expansion coefficients mismatch. Appl Phys Lett 112(4):042109
Khafagy KH, Hatem TM, Bedair SM (2018) Three-dimensional crystal-plasticity based model for intrinsic stresses in multi-junction photovoltaic. In: TMS annual meeting & exhibition. Springer, Cham, pp 453–461
Khafagy KH, Hatem TM, Bedair SM (2019) Modelling of III-Nitride epitaxial layers grown on silicon substrates with low dislocation-densities. MRS Adv 4(13):755–760
Salah SI, Hatem TM, Khalil EE, Bedair SM (2019) Embedded void approach effects on intrinsic stresses in laterally grown GaN-on-Si substrate. Mater Sci Eng B 242:104–110
Hatem TM, Zikry MA (2011) A model for determining initial dislocation-densities associated with martensitic transformations. Mater Sci Eng 27(10):1570–1573
El-Etriby AE, Abdel-Meguid ME, Shalan KM, Hatem TM, Bahei-El-Din YA (2015) A multi-scale based model for composite materials with embedded PZT filaments for energy harvesting. In: TMS middle east—mediterranean materials congress on energy and infrastructure systems (MEMA 2015). Springer, Cham, pp 361–379
Hatem TM, Zikry MA (2010) Deformation and failure of single-packets in martensitic steels. Comput Mater Continua 17(2):127–147
Hatem TM (2009) Microstructural modeling of heterogeneous failure modes in martensitic steels. North Carolina State University, North Carolina
Northrup JE, Romano LT, Neugebauer J (1999) Surface energetics, pit formation, and chemical ordering in InGaN alloys. Appl Phys Lett 74(16):2319–2321
Northrup JE, Neugebauer J (1999) Indium-induced changes in GaN (0001) surface morphology. Phys Rev B 60(12):R8473
Lobanova AV, Kolesnikova AL, Romanov AE, Karpov SY, Rudinsky ME, Yakovlev EV (2013) Mechanism of stress relaxation in (0001) InGaN/GaN via formation of V-shaped dislocation half-loops. Appl Phys Lett 103(15):152106
Qi W, Zhang J, Mo C, Wang X, Wu X, Quan Z, Wang G, Pan S, Fang F, Liu J, Jiang F (2017) Effects of thickness ratio of InGaN to GaN in superlattice strain relief layer on the optoelectrical properties of InGaN-based green LEDs grown on Si substrates. J Appl Phys 122(8):084504
Wu XH, Elsass CR, Abare A, Mack M, Keller S, Petroff PM, DenBaars SP, Speck JS, Rosner SJ (1998) Structural origin of V-defects and correlation with localized excitonic centers in InGaN/GaN multiple quantum wells. Appl Phys Lett 72(6):692–694
Kim J, Cho YH, Ko DS, Li XS, Won JY, Lee E, Park SH, Kim JY, Kim S (2014) Influence of V-pits on the efficiency droop in InGaN/GaN quantum wells. Opt Express 22(103):A857–A866
Frank FC (1951) LXXXIII. Crystal dislocations—elementary concepts and definitions. Lond Edinb Dublin Philos Mag J Sci 42(331):809–819
Van der Merwe JH, Ball CAB, Matthews JW (1975) Epitaxial growth. In: Matthews JW (ed) Part B. Academic, New York, p 493
Song TL (2005) Strain relaxation due to V-pit formation in In x Ga 1–x N/GaN epilayers grown on sapphire. J Appl Phys 98(8):084906
Suhir E (1997) Predicted thermal mismatch stresses in a cylindrical bi-material assembly adhesively bonded at its ends. J Appl Mech 64(1):15–22
Acknowledgements
The support from the Young Investigators Research Grant (No. YIRG05) at the British University in Egypt and Research Grant from the Academy of Scientific Research and Technology (ASRT) are greatly appreciated.
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2020 The Minerals, Metals & Materials Society
About this paper
Cite this paper
Khafagy, K.H., Hatem, T.M., Bedair, S.M. (2020). Dislocation-Based Thermodynamic Models of V-Pits Formation and Strain Relaxation in InGaN/GaN Epilayers on Si Substrates. In: TMS 2020 149th Annual Meeting & Exhibition Supplemental Proceedings. The Minerals, Metals & Materials Series. Springer, Cham. https://doi.org/10.1007/978-3-030-36296-6_188
Download citation
DOI: https://doi.org/10.1007/978-3-030-36296-6_188
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-030-36295-9
Online ISBN: 978-3-030-36296-6
eBook Packages: Chemistry and Materials ScienceChemistry and Material Science (R0)