Influence of As-N Interstitial Complexes on Strain Generated in GaAsN Epilayers Grown by AP-MOVPE

Energies

Wojciech Dawidowski¹  Damian Radziewicz¹  Beata Ściana¹  Joanna Jadczak²  Mercedes Gabás³  Mari Cruz López-Escalante⁴  Victor González de la Cruz⁴ 

[1] Faculty of Electronics, Photonics and Microsystems, Wrocław University of Science and Technology, Janiszewskiego 11/17, 50-372 Wrocław, Poland;Faculty of Fundamental Problems of Technology, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland;Instituto de Energía Solar, ETSIT—Universidad Politécnica de Madrid, Avda. Complutense 30, 28040 Madrid, Spain;The Nanotech Unit, Departamento de Física Aplicada I, Andalucía Tech, Universidad de Málaga, Campus de Teatinos s/n, 29071 Málaga, Spain;

关键词: III-V semiconductors;    dilute nitrides;    AP-MOVPE;    nitrogen interstitial complexes;    HRXRD;    XPS;   

DOI  :  10.3390/en15093036

来源: DOAJ

【 摘 要 】

This work presents an investigation of the fully strained GaAsN/GaAs heterostructures obtained by atmospheric pressure metalorganic vapor phase epitaxy, focusing on the analysis of the strain generated in the GaAsN epilayers and its correlation with the formation of split interstitial complexes (N-As)_As. We analyzed strained GaAsN epilayers with nitrogen contents and thicknesses varying from 0.93 to 1.81% and 65 to 130 nm, respectively. The composition and thickness were determined by high resolution X-ray diffraction, and the strain was determined by Raman spectroscopy, while the N-bonding configurations were determined by X-ray photoelectron spectroscopy. We found that the strain generated in the GaAsN epilayers is mainly caused by a lattice mismatch with the GaAs substrate. This macroscopic strain is independent of the amount of (N-As)_As interstitial defects, while the local strain, induced by an alloying effect, tends to decrease with an increasing ratio of (N-As)_As interstitial defects to substitutional nitrogen atoms incorporated into an arsenic sublattice—N_As. Here, we show experimentally, for the first time, a correlation between the strain in the GaAsN epilayers, caused by an alloying effect determined by Raman spectroscopy, and the (N-As)_As/N_As ratio estimated by the XPS method. We found out that the (N-As)_As interstitials compensate the local strain resulting from the presence of N in the GaAs matrix, if their amount does not exceed ~65% of the substitutional introduced nitrogen N_As.

【 授权许可】

Unknown