TY - JOUR

T1 - Raman and photoluminescence spectroscopy of SiGe layer evolution on Si(100) induced by dewetting

AU - Shklyaev, A. A.

AU - Volodin, V. A.

AU - Stoffel, M.

AU - Rinnert, H.

AU - Vergnat, M.

PY - 2018/1/7

Y1 - 2018/1/7

N2 - High temperature annealing of thick (40-100 nm) Ge layers deposited on Si(100) at ∼400 °C leads to the formation of continuous films prior to their transformation into porous-like films due to dewetting. The evolution of Si-Ge composition, lattice strain, and surface morphology caused by dewetting is analyzed using scanning electron microscopy, Raman, and photoluminescence (PL) spectroscopies. The Raman data reveal that the transformation from the continuous to porous film proceeds through strong Si-Ge interdiffusion, reducing the Ge content from 60% to about 20%, and changing the stress from compressive to tensile. We expect that Ge atoms migrate into the Si substrate occupying interstitial sites and providing thereby the compensation of the lattice mismatch. Annealing generates only one type of radiative recombination centers in SiGe resulting in a PL peak located at about 0.7 and 0.8 eV for continuous and porous film areas, respectively. Since annealing leads to the propagation of threading dislocations through the SiGe/Si interface, we can tentatively associate the observed PL peak to the well-known dislocation-related D1 band.

AB - High temperature annealing of thick (40-100 nm) Ge layers deposited on Si(100) at ∼400 °C leads to the formation of continuous films prior to their transformation into porous-like films due to dewetting. The evolution of Si-Ge composition, lattice strain, and surface morphology caused by dewetting is analyzed using scanning electron microscopy, Raman, and photoluminescence (PL) spectroscopies. The Raman data reveal that the transformation from the continuous to porous film proceeds through strong Si-Ge interdiffusion, reducing the Ge content from 60% to about 20%, and changing the stress from compressive to tensile. We expect that Ge atoms migrate into the Si substrate occupying interstitial sites and providing thereby the compensation of the lattice mismatch. Annealing generates only one type of radiative recombination centers in SiGe resulting in a PL peak located at about 0.7 and 0.8 eV for continuous and porous film areas, respectively. Since annealing leads to the propagation of threading dislocations through the SiGe/Si interface, we can tentatively associate the observed PL peak to the well-known dislocation-related D1 band.

KW - DISLOCATION-RELATED PHOTOLUMINESCENCE

KW - OPTICAL-PROPERTIES

KW - SILICON

UR - http://www.scopus.com/inward/record.url?scp=85041485209&partnerID=8YFLogxK

U2 - 10.1063/1.5009720

DO - 10.1063/1.5009720

M3 - Article

AN - SCOPUS:85041485209

VL - 123

JO - Journal of Applied Physics

JF - Journal of Applied Physics

SN - 0021-8979

IS - 1

M1 - 015304

ER -