TY - JOUR

T1 - Ultrafast Infrared Laser Crystallization of Amorphous Si/Ge Multilayer Structures

AU - Bulgakov, Alexander V

AU - Beránek, Jiří

AU - Volodin, Vladimir A

AU - Cheng, Yuzhu

AU - Levy, Yoann

AU - Nagisetty, Siva S

AU - Zukerstein, Martin

AU - Popov, Alexander A

AU - Bulgakova, Nadezhda M

N1 - Funding: A.V.B., Y.L., J.B., M.Z. and N.M.B. acknowledge the support of the European Regional Development Fund and the state budget of the Czech Republic (project BIATRI: no. CZ.02.1.01/0.0/0.0/15_003/0000445). J.B. also acknowledges the support of the Grant Agency of the Czech Technical University in Prague, grant no. SGS23/188/OHK4/3T/14. The study of V.A.V. and Y.C. was supported by the Ministry of Science and Higher Education of the Russian Federation, grant no. FSUS-2020-0029. A.A.P. acknowledges the program no. FFNN-2022-0018 of the Ministry of Science and Higher Education of Russia. The authors are grateful to “VTAN” NSU for providing equipment for Raman spectroscopy and HRTEM image analysis.

PY - 2023/5/6

Y1 - 2023/5/6

N2 - 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. Similar crystallization regimes were observed for both single-shot and multi-shot conditions, although at lower fluences and with a lower selectivity in the latter case. A theoretical analysis was carried out based on the laser energy absorption mechanisms, thermal stresses, and non-thermal effects.

AB - 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. Similar crystallization regimes were observed for both single-shot and multi-shot conditions, although at lower fluences and with a lower selectivity in the latter case. A theoretical analysis was carried out based on the laser energy absorption mechanisms, thermal stresses, and non-thermal effects.

UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-85159364096&origin=inward&txGid=aa91ec02fc939b05ca228f5480ccd90e

U2 - 10.3390/ma16093572

DO - 10.3390/ma16093572

M3 - Article

C2 - 37176457

VL - 16

JO - Materials

JF - Materials

SN - 1996-1944

IS - 9

M1 - 3572

ER -