RT journal article
T1 Growth interruption strategies for interface optimization in GaAsSb/GaAsN type-II superlattices
A1 Braza Blanco, María Verónica
A1 Ben Fernández, Teresa
A1 Flores Gallegos, Sara
A1 Fernández de los Reyes, Daniel
A1 Gallego-Carro, A.
A1 Stanojevic, L.
A1 Gacevic, Z.
A1 Ruiz Marín, Nazaret
A1 Ulloa, J.M.
A1 González Robledo, David
A2 Ciencia de los Materiales e Ingeniería Metalúrgica y Química Inorgánica
K1 Sb segregation
K1 Growth interruptions
K1 Superlattices
K1 Soaking
K1 And desorption
AB Recently, GaAsSb/GaAsN type II short-period superlattices (SLs) have been proposed as suitable structures to be implemented in the optimal design of monolithic multi-junction solar cells. However, due to strong surface Sb segregation, experimental Sb composition profiles differ greatly from the nominal square-wave design. In this work, the improvement of the interface quality of these SLs in terms of compositional abruptness and surface roughness has been evaluated by implementing different growth interruption times under Sb4/As4 (soaking) and As4 (desorption) overpressure conditions before and after the growth of GaAsSb layers, respectively. The com-bined effects of both processes enhance Sb distribution, achieving squarer compositional profiles with reduced surface roughness interfaces. It has been found that the improvement in compositional abruptness is quantita-tively much higher at the lower interface, during soaking, than at the upper interface during desorption. Conversely, a larger decrease in surface roughness is achieved at the upper interface than at the lower interface. Fitting of the Sb segregation profiles using the 3-layer kinetic fluid model has shown that the increase in Sb incorporation rate is due to the decrease in segregation energy, presumably to changes in the surface recon-struction of the floating layer at the surface.
PB ELSEVIER
SN 0169-4332
YR 2022
FD 2022-12
LK http://hdl.handle.net/10498/27523
UL http://hdl.handle.net/10498/27523
LA eng
DS Repositorio Institucional de la Universidad de Cádiz
RD 08-nov-2026