A demonstration of donor passivation through direct formation of V-As_i complexes in As-doped Ge_1−xSn_x

Afrina Khanam, Anurag Vohra, Jonatan Slotte, Ilja Makkonen, Roger Loo, Geoffrey Pourtois

Research output: Contribution to journalArticleScientificpeer-review

Abstract

Positron annihilation spectroscopy in the Doppler and coincidence Doppler mode was applied on Ge_1−xSn_x epitaxial layers, grown by chemical vapor deposition with different total As concentrations (∼10^19–10^21 cm−3), high active As concentrations (∼10^19 cm−3), and similar Sn concentrations (5.9%–6.4%). Positron traps are identified as mono-vacancy complexes. Vacancy-As complexes, V-As_i, formed during the growth were studied to deepen the understanding of the electrical passivation of the Ge_1−xSn_x:As epilayers. Larger mono-vacancy complexes, V-As_i (i≥2), are formed as the As doping increases. The total As concentration shows a significant impact on the saturation of the number of As atoms (i=4) around the vacancies in the sample epilayers. The presence of V-As_i complexes decreases the dopant activation in the Ge_1−xSn_x:As epilayers. Furthermore, the presence of Sn failed to hinder the formation of larger V-As_i complexes and thus failed to reduce the donor-deactivation
Original languageEnglish
Pages (from-to)0-7
Number of pages7
JournalJournal of Applied Physics
Volume127
Issue number9
DOIs
Publication statusPublished - 15 May 2020
MoE publication typeA1 Journal article-refereed

Fingerprint Dive into the research topics of 'A demonstration of donor passivation through direct formation of V-As_i complexes in As-doped Ge_1−xSn_x'. Together they form a unique fingerprint.

  • Cite this