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Title: Mechanism for persistent hexagonal island formation in AlN buffer layer during growth on Si (111) by plasma-assisted molecular beam epitaxy

Abstract

The characteristics of structure and morphology of AlN grown by a growth interruption method on Si (111) with plasma-assisted molecular beam epitaxy are investigated. It is found that the growth interruption method would improve the surface flatness of the AlN layer without the formation of Al droplets. However, AlN hexagonal islands were present and persistent throughout the entire growth owing to effective strain relaxation and Eherlich-Schowebel barrier effect of preexistent surface islands grown on higher terraces of the Si substrate. The density of threading dislocations underneath the hexagonal islands is much less than elsewhere in the film, which is presumably due to dislocation annihilation during the island growth process.

Authors:
; ; ;  [1];  [2]
  1. Department of Materials Science and Engineering, National Cheng Kung University, Tainan, 70101, Taiwan (China) and Frontier Material and Micro/Nano Science and Technology Center, National Cheng Kung University, Tainan, 70101 Taiwan (China)
  2. (China) and Center for Nanoscience and Nanotechnology, National Sun Yat-Sen University, Kaohsiung, 80424 Taiwan (China)
Publication Date:
OSTI Identifier:
20971934
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 90; Journal Issue: 21; Other Information: DOI: 10.1063/1.2741054; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALUMINIUM NITRIDES; CRYSTAL GROWTH; DISLOCATIONS; DROPLETS; LAYERS; MOLECULAR BEAM EPITAXY; MORPHOLOGY; PLASMA; SEMICONDUCTOR MATERIALS; STRESS RELAXATION; SUBSTRATES; THIN FILMS

Citation Formats

Hsu, K.-Y., Chung, H.-C., Liu, C.-P., Tu, L.-W., and Department of Physics, National Sun Yat-Sen University, Kaohsiung, 80424 Taiwan. Mechanism for persistent hexagonal island formation in AlN buffer layer during growth on Si (111) by plasma-assisted molecular beam epitaxy. United States: N. p., 2007. Web. doi:10.1063/1.2741054.
Hsu, K.-Y., Chung, H.-C., Liu, C.-P., Tu, L.-W., & Department of Physics, National Sun Yat-Sen University, Kaohsiung, 80424 Taiwan. Mechanism for persistent hexagonal island formation in AlN buffer layer during growth on Si (111) by plasma-assisted molecular beam epitaxy. United States. doi:10.1063/1.2741054.
Hsu, K.-Y., Chung, H.-C., Liu, C.-P., Tu, L.-W., and Department of Physics, National Sun Yat-Sen University, Kaohsiung, 80424 Taiwan. Mon . "Mechanism for persistent hexagonal island formation in AlN buffer layer during growth on Si (111) by plasma-assisted molecular beam epitaxy". United States. doi:10.1063/1.2741054.
@article{osti_20971934,
title = {Mechanism for persistent hexagonal island formation in AlN buffer layer during growth on Si (111) by plasma-assisted molecular beam epitaxy},
author = {Hsu, K.-Y. and Chung, H.-C. and Liu, C.-P. and Tu, L.-W. and Department of Physics, National Sun Yat-Sen University, Kaohsiung, 80424 Taiwan},
abstractNote = {The characteristics of structure and morphology of AlN grown by a growth interruption method on Si (111) with plasma-assisted molecular beam epitaxy are investigated. It is found that the growth interruption method would improve the surface flatness of the AlN layer without the formation of Al droplets. However, AlN hexagonal islands were present and persistent throughout the entire growth owing to effective strain relaxation and Eherlich-Schowebel barrier effect of preexistent surface islands grown on higher terraces of the Si substrate. The density of threading dislocations underneath the hexagonal islands is much less than elsewhere in the film, which is presumably due to dislocation annihilation during the island growth process.},
doi = {10.1063/1.2741054},
journal = {Applied Physics Letters},
number = 21,
volume = 90,
place = {United States},
year = {Mon May 21 00:00:00 EDT 2007},
month = {Mon May 21 00:00:00 EDT 2007}
}
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