NaF/RbF-Treated Cu(In,Ga)Se2 Thin-Film Solar Cell Absorbers: Distinct Surface Modifications Caused by Two Different Types of Rubidium Chemistry.
ACS Appl Mater Interfaces
; 12(31): 34941-34948, 2020 Aug 05.
Article
en En
| MEDLINE
| ID: mdl-32633119
ABSTRACT
The underlying beneficial mechanism of heavy alkali postdeposition treatment (PDT) of Cu(In,Ga)Se2 thin-film solar cell absorbers that led to new record efficiencies in recent years is studied using photoelectron spectroscopy. Excitation energies between 40.8 eV and 6 keV were used to examine the near-surface region of Cu(In,Ga)Se2 thin-film solar cell absorbers that underwent NaF and combined NaF/RbF PDT. The already Cu-deficient surface region after NaF PDT, which is modeled as a Cu(In + Ga)Se = 158 phase, shows further depletion after NaF/RbF PDT and seems to incorporate some Rb. Additionally, we have found strong indications for the NaF/RbF PDT-induced formation of a Rb-In-Se-type compound with a 112 stoichiometry partially covering the absorber surface. The electronic Cu(In,Ga)Se2 structure is modified due to the RbF treatment, with a pronounced shift in the valence band maximum away from the Fermi level in the immediate vicinity of the surface.
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Idioma:
En
Revista:
ACS Appl Mater Interfaces
Asunto de la revista:
BIOTECNOLOGIA
/
ENGENHARIA BIOMEDICA
Año:
2020
Tipo del documento:
Article
País de afiliación:
Alemania