Abstract
Optical properties of Ge/Si superlattices grown at low temperatures with strain-induced ripple structures were characterized by electroreflectance (ER) and resonance Raman spectroscopy. There were three types of samples under investigation. The growth temperatures of the Ge layers were 250, 300, and 350 °C. The diffusion length of Ge atom at such low temperatures is considerably smaller, and three-dimensional island growth is kinetically delayed or frozen out. The cross-sectional transmission electron microscope (TEM) image of the sample showed that strain-induced Ge/Si intermixing forms stacked SiGe-alloy ripples in the Si layers to release the strain in the Ge layers. When the Ge growth temperature decreases, the spectral feature of the Ge E1 transition is shifted and enhanced because the three-dimensional island growth is kinetically suppressed, the Ge/Si intermixing formation of strain relieving stacking ripples is in favor, and the optical transition is enhanced. The same optical transition and enhancement is confirmed by the resonance Raman spectroscopy.
| Original language | English |
|---|---|
| Pages (from-to) | 490-492 |
| Number of pages | 3 |
| Journal | Journal of Physics and Chemistry of Solids |
| Volume | 69 |
| Issue number | 2-3 |
| DOIs | |
| Publication status | Published - 2008 Jan 1 |
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Keywords
- A. Semiconductors
- D. Optical properties
- D. Superlattices
ASJC Scopus subject areas
- Chemistry(all)
- Materials Science(all)
- Condensed Matter Physics
Cite this
Optical characterization of Ge/Si superlattices with stacked nanoripples. / Lee, J. R.; Lin, S. C.; Lu, Chien-Rong; Lin, J. H.; Chia, Chi-Ta; Chang, H. H.
In: Journal of Physics and Chemistry of Solids, Vol. 69, No. 2-3, 01.01.2008, p. 490-492.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Optical characterization of Ge/Si superlattices with stacked nanoripples
AU - Lee, J. R.
AU - Lin, S. C.
AU - Lu, Chien-Rong
AU - Lin, J. H.
AU - Chia, Chi-Ta
AU - Chang, H. H.
PY - 2008/1/1
Y1 - 2008/1/1
N2 - Optical properties of Ge/Si superlattices grown at low temperatures with strain-induced ripple structures were characterized by electroreflectance (ER) and resonance Raman spectroscopy. There were three types of samples under investigation. The growth temperatures of the Ge layers were 250, 300, and 350 °C. The diffusion length of Ge atom at such low temperatures is considerably smaller, and three-dimensional island growth is kinetically delayed or frozen out. The cross-sectional transmission electron microscope (TEM) image of the sample showed that strain-induced Ge/Si intermixing forms stacked SiGe-alloy ripples in the Si layers to release the strain in the Ge layers. When the Ge growth temperature decreases, the spectral feature of the Ge E1 transition is shifted and enhanced because the three-dimensional island growth is kinetically suppressed, the Ge/Si intermixing formation of strain relieving stacking ripples is in favor, and the optical transition is enhanced. The same optical transition and enhancement is confirmed by the resonance Raman spectroscopy.
AB - Optical properties of Ge/Si superlattices grown at low temperatures with strain-induced ripple structures were characterized by electroreflectance (ER) and resonance Raman spectroscopy. There were three types of samples under investigation. The growth temperatures of the Ge layers were 250, 300, and 350 °C. The diffusion length of Ge atom at such low temperatures is considerably smaller, and three-dimensional island growth is kinetically delayed or frozen out. The cross-sectional transmission electron microscope (TEM) image of the sample showed that strain-induced Ge/Si intermixing forms stacked SiGe-alloy ripples in the Si layers to release the strain in the Ge layers. When the Ge growth temperature decreases, the spectral feature of the Ge E1 transition is shifted and enhanced because the three-dimensional island growth is kinetically suppressed, the Ge/Si intermixing formation of strain relieving stacking ripples is in favor, and the optical transition is enhanced. The same optical transition and enhancement is confirmed by the resonance Raman spectroscopy.
KW - A. Semiconductors
KW - D. Optical properties
KW - D. Superlattices
UR - http://www.scopus.com/inward/record.url?scp=38749122074&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=38749122074&partnerID=8YFLogxK
U2 - 10.1016/j.jpcs.2007.07.034
DO - 10.1016/j.jpcs.2007.07.034
M3 - Article
VL - 69
SP - 490
EP - 492
JO - Journal of Physics and Chemistry of Solids
JF - Journal of Physics and Chemistry of Solids
SN - 0022-3697
IS - 2-3
ER -