| Title |
The crystalline structure of thin bismuth layers grown on silicon (111) substrates / |
| Authors |
Stanionytė, Sandra ; Malinauskas, Tadas ; Niaura, Gediminas ; Skapas, Martynas ; Devenson, Jan ; Krotkus, Arūnas |
| DOI |
10.3390/ma15144847 |
| Full Text |
|
| Is Part of |
Materials.. Basel : MDPI AG. 2022, vol. 15, iss. 14, art. no. 4847, p. 1-12.. eISSN 1996-1944 |
| Keywords [eng] |
bismuth thin film ; molecular beam epitaxy ; high-resolution X-ray diffraction |
| Abstract [eng] |
Bismuth films with thicknesses between 6 and ∼30 nm were grown on Si (111) substrate by molecular beam epitaxy (MBE). Two main phases of bismuth — α-Bi and β-Bi — were identified from high-resolution X-ray diffraction (XRD) measurements. The crystal structure dependencies on the layer thicknesses of these films were analyzed. β-Bi layers were epitaxial and homogenous in lateral regions that are greater than 200 nm despite the layer thickness. Further, an increase in in-plane 2θ values showed the biaxial compressive strain. For comparison, α-Bi layers are misoriented in six in-plane directions and have β-Bi inserts in thicker layers. That leads to smaller (about 60 nm) lateral crystallites which are compressively strained in all three directions. Raman measurement confirmed the XRD results. The blue-sift of Raman signals compared with bulk Bi crystals occurs due to the phonon confinement effect, which is larger in the thinnest α-Bi layers due to higher compression. |
| Published |
Basel : MDPI AG |
| Type |
Journal article |
| Language |
English |
| Publication date |
2022 |
| CC license |
|
