RT journal article
T1 Suppressing the Effect of the Wetting Layer through AlAs Capping in InAs/GaAs QD Structures for Solar Cells Applications
A1 Ruiz Marín, Nazaret
A1 Fernández de los Reyes, Daniel
A1 Stanojevic, Lazar
A1 Ben Fernández, Teresa
A1 Flores Gallegos, Sara
A1 Braza Blanco, María Verónica
A1 Gallego-Carro, A.
A1 Luna, Esperanza
A1 Ulloa, José María
A1 González Robledo, David
A2 Ciencia de los Materiales e Ingeniería Metalúrgica y Química Inorgánica
A2 Física de la Materia Condensada
K1 InAs quantum dots solar cells
K1 AlAs capping
K1 (S)TEM
AB Recently, thin AlAs capping layers (CLs) on InAs quantum dot solar cells (QDSCs) have been shown to yield better photovoltaic efficiency compared to traditional QDSCs. Although it has been proposed that this improvement is due to the suppression of the capture of photogenerated carriers through the wetting layer (WL) states by a de-wetting process, the mechanisms that operate during this process are not clear. In this work, a structural analysis of the WL characteristics in the AlAs/InAs QD system with different CL-thickness has been made by scanning transmission electron microscopy techniques. First, an exponential decline of the amount of InAs in the WL with the CL thickness increase has been found, far from a complete elimination of the WL. Instead, this reduction is linked to a higher shield effect against QD decomposition. Second, there is no compositional separation between the WL and CL, but rather single layer with a variable content of InAlGaAs. Both effects, the high intermixing and WL reduction cause a drastic change in electronic levels, with the CL making up of 1-2 monolayers being the most effective configuration to reduce the radiative-recombination and minimize the potential barriers for carrier transport.
PB MDPI
SN 2079-4991
YR 2022
FD 2022-04
LK http://hdl.handle.net/10498/26961
UL http://hdl.handle.net/10498/26961
LA eng
NO The work has been co-financed by the Spanish National Research Agency (AEI projects MAT2016-77491-C2-2-R and PID2019-106088RB-C33), Regional Government of Andalusia (project FEDER-UCA18-108319) and the European Regional Development Fund (ERDF).
DS Repositorio Institucional de la Universidad de Cádiz
RD 11-nov-2026