TY - GEN

T1 - Stress-induced indirect to direct band gap transition in β -FeSi2 nanocrystals embedded in Si

AU - Shevlyagin, A. V.

AU - Goroshko, D. L.

AU - Chusovitin, E. A.

AU - Balagan, S. A.

AU - Dotsenko, S. A.

AU - Galkin, K. N.

AU - Galkin, N. G.

AU - Shamirzaev, T. S.

AU - Gutakovskii, A. K.

AU - Iinuma, M.

AU - Terai, Y.

PY - 2017/9/14

Y1 - 2017/9/14

N2 - Embedded in silicon β-FeSi2 nanocrystals (NCs) were grown on Si(111) by solid phase epitaxy of a thin iron film followed by Si molecular beam epitaxy. After solid phase epitaxy, a mixture of β-FeSi2 and ϵ-FeSi nanocrystals is formed on the surface, sometimes β and ϵ phases coexist inside one nanocrystal. During initial stage of Si molecular beam epitaxy all ϵ-FeSi transforms into β-FeSi2. β-FeSi2 nanocrystals tend to move following Si growth front. By adjusting growth condition, we manage to prevent the nanocrystals from moving and to fabricate 7-layer n-Si(111)/β-FeSi2-NCs/p+-Si silicon heterostructure with embedded β-FeSi2 NCs. An epitaxial relationship and a stress induced in the nanocrystals by silicon matrix were found to be suitable for indirect to direct band gap transition in β-FeSi2. Of the heterostructure, a n-i-p avalanche photodetector and a light-emitting diode were formed. They have shown relatively good performance: ultrabroadband photoresponse from the visible (400 nm) to short-wavelength infrared (1800 nm) ranges owing to quantum-confined Stark effect in the nanocrystals and optical emission power of up to 25 μW at 9 A/cm2 with an external quantum efficiency of 0.009% at room temperature owing to a direct fundamental transition in stressed β-FeSi2 nanocrystals.

AB - Embedded in silicon β-FeSi2 nanocrystals (NCs) were grown on Si(111) by solid phase epitaxy of a thin iron film followed by Si molecular beam epitaxy. After solid phase epitaxy, a mixture of β-FeSi2 and ϵ-FeSi nanocrystals is formed on the surface, sometimes β and ϵ phases coexist inside one nanocrystal. During initial stage of Si molecular beam epitaxy all ϵ-FeSi transforms into β-FeSi2. β-FeSi2 nanocrystals tend to move following Si growth front. By adjusting growth condition, we manage to prevent the nanocrystals from moving and to fabricate 7-layer n-Si(111)/β-FeSi2-NCs/p+-Si silicon heterostructure with embedded β-FeSi2 NCs. An epitaxial relationship and a stress induced in the nanocrystals by silicon matrix were found to be suitable for indirect to direct band gap transition in β-FeSi2. Of the heterostructure, a n-i-p avalanche photodetector and a light-emitting diode were formed. They have shown relatively good performance: ultrabroadband photoresponse from the visible (400 nm) to short-wavelength infrared (1800 nm) ranges owing to quantum-confined Stark effect in the nanocrystals and optical emission power of up to 25 μW at 9 A/cm2 with an external quantum efficiency of 0.009% at room temperature owing to a direct fundamental transition in stressed β-FeSi2 nanocrystals.

KW - SI(001)

UR - http://www.scopus.com/inward/record.url?scp=85030632924&partnerID=8YFLogxK

U2 - 10.1063/1.4998036

DO - 10.1063/1.4998036

M3 - Conference contribution

AN - SCOPUS:85030632924

VL - 1874

T3 - AIP Conference Proceedings

BT - Proceedings of International Conference on Metamaterials and Nanophotonics, METANANO 2017

PB - American Institute of Physics Inc.

T2 - International Conference on Metamaterials and Nanophotonics, METANANO 2017

Y2 - 18 September 2017 through 22 September 2017

ER -