Applied Nanoscience

, Volume 8, Issue 4, pp 891–903 | Cite as

Spectroscopic and microscopic investigation of MBE-grown CdTe (211)B epitaxial thin films on GaAs (211)B substrates

  • Selin Özden
  • Mumin Mehmet Koc
Original Article


CdTe epitaxial thin films, for use as a buffer layer for HgCdTe defectors, were grown on GaAs (211)B using the molecular beam epitaxy method. Wet chemical etching (Everson method) was applied to the epitaxial films using various concentrations and application times to quantify the crystal quality and dislocation density. Surface characterization of the epitaxial films was achieved using Atomic force microscopy and Scanning electron microscopy (SEM) before and after each treatment. The Energy Dispersive X-Ray apparatus of SEM was used to characterize the chemical composition. Untreated CdTe films show smooth surface characteristics with root mean square (RMS) roughnesses of 1.18–3.89 nm. The thicknesses of the CdTe layers formed were calculated via FTIR spectrometry and obtained by ex situ spectroscopic ellipsometry. Raman spectra were obtained for various temperatures. Etch pit densities (EPD) were measured, from which it could be seen that EPD changes between 1.7 × 108 and 9.2 × 108 cm−2 depending on the concentration of the Everson etch solution and treatment time. Structure, shape and depth of pits resulting from each etch pit implementation were also evaluated. Pit widths varying between 0.15 and 0.71 µm with heights varying between 2 and 80 nm were observed. RMS roughness was found to vary by anything from 1.56 to 26 nm.


CdTe films CdTe buffer layer Etch pit density Raman spectroscopy Atomic force microscopy Scanning electron microscopy 



This study was supported by the Gediz Project at Izmir Institute of Technology. The authors would like to thank all supporters for their assistance with the project. This paper is dedicated to the memory of Prof Yusuf Selamet, who sadly passed away in 2016. We are grateful to him for his guidance, endless support and giving us the chance to work with him. In addition, we would like to thank Elif Bilgilisoy for helping in etching CdTe epitaxial films and also Merve Karakaya for Spectroscopic Ellipsometry analysis. Use of facilities at the IZTECH Material Research Center for scanning electron microscopy is acknowledged.

Compliance with ethical standards

Conflict of interest

On behalf of all authors, the corresponding author states that there is no conflict of interest.


  1. Abbott P, Pillans L, Knowles P, McEwen RK (2010) Advances in dual-band IRFPAs made from HgCdTe grown by MOVPE. Soc Photo Optical Instrum Eng SPIE Conf Ser 7660:1–11Google Scholar
  2. Badano G, Robin IC, Amstatt B, Gemain F, Baudry X (2010) Reduction of the dislocation density in molecular beam epitaxial CdTe(2 1 1)B on Ge(2 1 1). J Cryst Growth 312(10):1721–1725CrossRefGoogle Scholar
  3. Benson JD et al (2008) Structural analysis of CdTe hetero-epitaxy on (211) Si. J Electron Mater 37(9):1231–1236CrossRefGoogle Scholar
  4. Benson JD et al (2012) Growth and analysis of HgCdTe on alternate substrates. J Electron Mater 41(10):2971–2974CrossRefGoogle Scholar
  5. Bilgilisoy E, Özden S, Bakali E, Karakaya M, Selamet Y (2015) Characterization of CdTe growth on GaAs using different etching techniques. J Electron Mater 44(9):3124–3133CrossRefGoogle Scholar
  6. Capper P (1994) Properties of narrow gap cadmium-based compoundsGoogle Scholar
  7. Chen JS (1990) U.S. Patent No. 4,897,152. U.S. Patent and Trademark Office, Washington, DCGoogle Scholar
  8. Cheung JT, Khoshnevisan M, Magee T (1983) Heteroepitaxial growth of CdTe on GaAs by laser assisted deposition. Appl Phys Lett 43(5):462–464CrossRefGoogle Scholar
  9. Dhar NK, Boyd PR, Martinka M, Dinan JH, Almeida LA, Goldsman N (2000) CdZnTe heteroepitaxy on 3 (112) Si: interface, surface, and layer characteristics. J Electron Mater 29(6):748–753CrossRefGoogle Scholar
  10. Everson WJ, Ard CK, Sepich JL, Dean BE, Neugebauer GT, Schaake HF (1995) Etch pit characterization of CdTe and CdZnTe substrates for use in mercury cadmium telluride epitaxy. J Electron Mater 24(5):505–510CrossRefGoogle Scholar
  11. Farrell S et al (2011) Effect of cycle annealing parameters on dislocation density reduction for HgCdTe on Si. J Electron Mater 40(8):1727–1732CrossRefGoogle Scholar
  12. Farrow RFC, Jones GR, Williams GM, Young IM (1981) Molecular beam epitaxial growth of high structural perfection, heteroepitaxial CdTe films on InSb (001). Appl Phys Lett 39(12):954–956CrossRefGoogle Scholar
  13. Guo SP, Zhang JM, Liu PL, Shen XC, Yuan SX, Tomm JW (1996) Study of molecular beam epitaxial growth and optical characteristics of HgCdTe. Acta Physica Sincia (Overseas Edition) 5(5):370CrossRefGoogle Scholar
  14. Hähnert I, Schenk M (1990) New defect etchants for CdTe and Hg1-xCdxTe. J Cryst Growth 101:251–255CrossRefGoogle Scholar
  15. He L et al (2007) MBE HgCdTe on Si and GaAs substrates. J Cryst Growth 301–302(SPEC. ISS):268–272CrossRefGoogle Scholar
  16. He L et al (2008) MBE HgCdTe on alternative substrates for FPA applications. J Electron Mater 37(9):1189–1199CrossRefGoogle Scholar
  17. Jacobs RN et al (2012) Development of MBE II-VI epilayers on GaAs (211)B. J Electron Mater 41(10):2707–2713CrossRefGoogle Scholar
  18. Jin L et al (2014) Fabrication, mechanical properties, and biocompatibility of reduced graphene oxide-reinforced nanofiber mats. RSC Adv 4(66):35035–35041CrossRefGoogle Scholar
  19. Johnson SM et al (1993) MOCVD grown CdZn Te/GaAs/Si substrates for large-area HgCdTe IRFPAs. J Electron Mater 22(8):835–842CrossRefGoogle Scholar
  20. Johnson SM et al (1995) Direct growth of CdZnTe/Si substrates for large-area HgCdTe infrared focal plane arrays. J Electron Mater 24(5):467–473CrossRefGoogle Scholar
  21. Kasap S, Willoughby A (2011) Mercury cadmium telluride: growth, properties and applications. In: Mercury cadmium telluride: growth, properties and applications, vol. 38Google Scholar
  22. Krishnamurthy M, Petroff PM, Arias JM (1993) P on n heterostructures in HgCdTe on GaAs analyzed by transmission electron microscopy. J Appl Phys 73(11):7952–7954CrossRefGoogle Scholar
  23. Lawson WD, Nielsen S, Putley EH, Young AS (1959) Preparation and properties of HgTe and mixed crystals of HgTe-CdTe. J Phys Chem Solids 9(3–4):325–329CrossRefGoogle Scholar
  24. Lu YC, Route RK, Elwell D, Feigelson RS (1985) Etch pit studies in CdTe crystals. J Vac Sci Technol A Vac Surf Film 3(1):264–270CrossRefGoogle Scholar
  25. Myers TH, Lo Y, Bicknell RN, Schetzina JF (1983) Growth of CdTe films on sapphire by molecular beam epitaxy. Appl Phys Lett 42(3):247–248CrossRefGoogle Scholar
  26. Nishitani K, Ohkata R, Murotani T (1983) Molecular beam epitaxy of CdTe and Hg1-xCdxTe ON GaAs (100). J Electron Mater 3(12):619–635CrossRefGoogle Scholar
  27. Tian Y et al (2017) Carbon nanotube/polyurethane films with high transparency, low sheet resistance and strong adhesion for antistatic application. RSC Adv 7(83):53018–53024CrossRefGoogle Scholar
  28. Yang S, Wang Y, Liu P, Cheng Y-B, Zhao HJ, Yang HG (2016) Functionalization of perovskite thin films with moisture-tolerant molecules. Nat Energy 1(2):15016CrossRefGoogle Scholar
  29. Zanatta JP et al (2006) Molecular beam epitaxy growth of HgCdTe on Ge for third-generation infrared detectors. J Electron Mater 35(6):1231–1236CrossRefGoogle Scholar

Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of PhysicsKirklareli UniversityKirklareliTurkey
  2. 2.School of EngineeringUniversity of PortsmouthPortsmouthUK

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