Ultrafast infrared laser crystallization of amorphous Si/Ge multilayer structures

0571963 - FZÚ 2024 RIV CH eng J - Journal Article
Bulgakov, Alexander - Beránek, Jiří - Volodin, V.A. - Cheng, Y. - Levy, Yoann - Nagisetty, S.S. - Zukerstein, Martin - Popov, A. A. - Bulgakova, Nadezhda M.
Ultrafast infrared laser crystallization of amorphous Si/Ge multilayer structures.
Materials. Roč. 16, č. 9 (2023), č. článku 3572. E-ISSN 1996-1944
R&D Projects: GA MŠMT EF15_003/0000445
Grant - others:OP VVV - BIATRI(XE) CZ.02.1.01/0.0/0.0/15_003/0000445
Institutional support: RVO:68378271
Keywords : silicon–germanium multilayer structures * thin films * ultrashort infrared laser annealing * selective crystallization * defect accumulation * Raman spectroscopy
OECD category: Optics (including laser optics and quantum optics)
Impact factor: 3.4, year: 2022
Method of publishing: Open access

Silicon–germanium multilayer structures consisting of alternating Si and Ge amorphous nanolayers were annealed by ultrashort laser pulses at near-infrared (1030 nm) and mid-infrared (1500 nm) wavelengths. In this paper, we investigate the effects of the type of substrate (Si or glass), and the number of laser pulses (single-shot and multi-shot regimes) on the crystallization of the layers. Based on structural Raman spectroscopy analysis, several annealing regimes were revealed depending on laser fluence, including partial or complete crystallization of the components and formation of solid Si–Ge alloys. Conditions for selective crystallization of germanium when Si remains amorphous and there is no intermixing between the Si and Ge layers were found. Femtosecond mid-IR laser annealing appeared to be particularly favorable for such selective crystallization.
Permanent Link: https://hdl.handle.net/11104/0342818