Abstract
High-resolution X-ray diffraction in coplanar and noncoplanar geometries has been used to investigate the influence of an SiN x nano-mask in the reduction of the threading dislocation (TD) density of high-quality AlGaN epitaxial layers grown on sapphire substrates. Our developed model, based on a Monte Carlo method, was applied to the simulation of the reciprocal-space maps of a two-layer system. Good agreement was found between the simulation and the experimental data, leading to an accurate determination of the dislocation densities as a function of the overgrowth layer thickness. The efficiency of the SiN x nano-mask was defined as the ratio of the TD densities in the AlGaN layers below and above the mask. A significant improvement in the AlGaN layer quality was achieved by increasing the overgrowth layer thickness, and a TD density reduction scaling law was established.
| Original language | English |
|---|---|
| Pages (from-to) | 120-127 |
| Number of pages | 8 |
| Journal | Journal of Applied Crystallography |
| Volume | 46 |
| Issue number | 1 |
| DOIs | |
| Publication status | Published - Feb 2013 |
| Externally published | Yes |
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Keywords
- epitaxial layers
- high-resolution X-ray diffraction
- nano-masking
- threading dislocation density
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)
Cite this
Study of threading dislocation density reduction in AlGaN epilayers by Monte Carlo simulation of high-resolution reciprocal-space maps of a two-layer system. / Lazarev, S.; Barchuk, M.; Bauer, S.; Forghani, K.; Holý, V.; Scholz, F.; Baumbach, T.
In: Journal of Applied Crystallography, Vol. 46, No. 1, 02.2013, p. 120-127.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Study of threading dislocation density reduction in AlGaN epilayers by Monte Carlo simulation of high-resolution reciprocal-space maps of a two-layer system
AU - Lazarev, S.
AU - Barchuk, M.
AU - Bauer, S.
AU - Forghani, K.
AU - Holý, V.
AU - Scholz, F.
AU - Baumbach, T.
PY - 2013/2
Y1 - 2013/2
N2 - High-resolution X-ray diffraction in coplanar and noncoplanar geometries has been used to investigate the influence of an SiN x nano-mask in the reduction of the threading dislocation (TD) density of high-quality AlGaN epitaxial layers grown on sapphire substrates. Our developed model, based on a Monte Carlo method, was applied to the simulation of the reciprocal-space maps of a two-layer system. Good agreement was found between the simulation and the experimental data, leading to an accurate determination of the dislocation densities as a function of the overgrowth layer thickness. The efficiency of the SiN x nano-mask was defined as the ratio of the TD densities in the AlGaN layers below and above the mask. A significant improvement in the AlGaN layer quality was achieved by increasing the overgrowth layer thickness, and a TD density reduction scaling law was established.
AB - High-resolution X-ray diffraction in coplanar and noncoplanar geometries has been used to investigate the influence of an SiN x nano-mask in the reduction of the threading dislocation (TD) density of high-quality AlGaN epitaxial layers grown on sapphire substrates. Our developed model, based on a Monte Carlo method, was applied to the simulation of the reciprocal-space maps of a two-layer system. Good agreement was found between the simulation and the experimental data, leading to an accurate determination of the dislocation densities as a function of the overgrowth layer thickness. The efficiency of the SiN x nano-mask was defined as the ratio of the TD densities in the AlGaN layers below and above the mask. A significant improvement in the AlGaN layer quality was achieved by increasing the overgrowth layer thickness, and a TD density reduction scaling law was established.
KW - epitaxial layers
KW - high-resolution X-ray diffraction
KW - nano-masking
KW - threading dislocation density
UR - http://www.scopus.com/inward/record.url?scp=84872720760&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84872720760&partnerID=8YFLogxK
U2 - 10.1107/S0021889812043051
DO - 10.1107/S0021889812043051
M3 - Article
AN - SCOPUS:84872720760
VL - 46
SP - 120
EP - 127
JO - Journal of Applied Crystallography
JF - Journal of Applied Crystallography
SN - 0021-8898
IS - 1
ER -