TY - JOUR
T1 - Investigation of the effect of substrate orientation on the structural, electrical and optical properties of n-type GaAs1−xBix layers grown by Molecular Beam Epitaxy
AU - Alhassan, Sultan
AU - de Souza, Daniele
AU - Alhassni, Amra
AU - Almunyif, Amjad
AU - Alotaibi, Saud
AU - Almalki, A.
AU - Alhuwayz, M.
AU - Kazakov, Igor P.
AU - Klekovkin, Alexey V.
AU - Tsekhosh, Vladimir I.
AU - Likhachev, Igor A.
AU - Pashaev, Elkhan M.
AU - Souto, Sergio
AU - Gobato, Yara Galvão
AU - Saqri, N. Al
AU - Galeti, Helder Vinicius Avanço
AU - Al mashary, Faisal
AU - Albalawi, Hind
AU - Alwadai, Norah
AU - Henini, Mohamed
N1 - Funding Information:
The work has been supported by “ Fundação de Amparo a Pesquisa do Estado de São Paulo ” ( Fapesp) (grants no. 19/23488–5 and 19/07442–5 ) and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPQ) (grants 426634/2018–7 and 311678/2020–3 ). S. Alhassan would like to acknowledge support from Jouf University, Aljouf, Saudi Arabia for providing scholarship for his PhD degree. D de Souza acknowledges the financial support of “ Coordenação de Aperfeiçoamento de Pessoal de Nível Superior ” (Capes) for her PhD scholarship. M. Henini, H. Albalawi and N. Alwadai acknowledge the support by a grant from the deanship of scientific research, Princess Nourah bint Abdulrahman University, Riyadh, KSA.
Publisher Copyright:
© 2021 Elsevier B.V.
PY - 2021/12/10
Y1 - 2021/12/10
N2 - Current-Voltage (I-V), Capacitance-Voltage (C-V), Deep Level Transient Spectroscopy (DLTS), Laplace DLTS, Photoluminescence (PL) and Micro-Raman techniques have been employed to investigate the effect of the orientation of the substrates on the structural, electrically and optically active defects in dilute GaAs1−xBix epilayers structures having a Bi composition x = ~5.4%, grown by Molecular Beam Epitaxy (MBE) on (100) and (311)B GaAs planes. X-ray diffraction results revealed that the in-plane strain in the Ga(As,Bi) layer of the samples grown on (100)-oriented substrate (−0.0484) is significantly larger than that of the samples grown on (311)B-oriented substrate. The substrate orientation is found to have a noticeable impact on the Bi incorporation and the electrical properties of dilute GaAsBi Schottky diodes. The I-V characteristics showed that (100) Schottky diodes exhibited a larger ideality factor and higher barrier height compared with (311)B samples. The DLTS measurements showed that the number of electrically active traps were different for the two GaAs substrate orientations. In particular, three and two electron traps are detected in samples grown on (100) and (311)B GaAs substrates, respectively, with activation energies ranging from 0.12 to 0.41 eV. Additionally, one hole trap was observed only in sample grown on (100) substrates with activation energy 0.24 eV. The observed traps with small activation energies are attributed to Bi pair defects. The photoluminescence (PL) and Raman spectra have evidenced different compressive strain which affects considerably the optical properties. Furthermore, the PL spectra were also affected by different contributions of Bi- related traps which are different for different substrate orientation in agreement with DLTS results.
AB - Current-Voltage (I-V), Capacitance-Voltage (C-V), Deep Level Transient Spectroscopy (DLTS), Laplace DLTS, Photoluminescence (PL) and Micro-Raman techniques have been employed to investigate the effect of the orientation of the substrates on the structural, electrically and optically active defects in dilute GaAs1−xBix epilayers structures having a Bi composition x = ~5.4%, grown by Molecular Beam Epitaxy (MBE) on (100) and (311)B GaAs planes. X-ray diffraction results revealed that the in-plane strain in the Ga(As,Bi) layer of the samples grown on (100)-oriented substrate (−0.0484) is significantly larger than that of the samples grown on (311)B-oriented substrate. The substrate orientation is found to have a noticeable impact on the Bi incorporation and the electrical properties of dilute GaAsBi Schottky diodes. The I-V characteristics showed that (100) Schottky diodes exhibited a larger ideality factor and higher barrier height compared with (311)B samples. The DLTS measurements showed that the number of electrically active traps were different for the two GaAs substrate orientations. In particular, three and two electron traps are detected in samples grown on (100) and (311)B GaAs substrates, respectively, with activation energies ranging from 0.12 to 0.41 eV. Additionally, one hole trap was observed only in sample grown on (100) substrates with activation energy 0.24 eV. The observed traps with small activation energies are attributed to Bi pair defects. The photoluminescence (PL) and Raman spectra have evidenced different compressive strain which affects considerably the optical properties. Furthermore, the PL spectra were also affected by different contributions of Bi- related traps which are different for different substrate orientation in agreement with DLTS results.
KW - Defects
KW - Dilute bismides
KW - Doped semiconductor
KW - Electrical properties
KW - Optical properties
KW - Structural disorder
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U2 - 10.1016/j.jallcom.2021.161019
DO - 10.1016/j.jallcom.2021.161019
M3 - Article
AN - SCOPUS:85109162394
SN - 0925-8388
VL - 885
JO - Journal of Alloys and Compounds
JF - Journal of Alloys and Compounds
M1 - 161019
ER -