Nanoscale Growth Kinetics of Cu(In,Ga)Se2 Absorbers

Autor: Michael Stuckelberger, Barry Lai, Mariana I. Bertoni, Jörg Maser, Bradley West
Rok vydání: 2018
Předmět:
Zdroj: The Journal of Physical Chemistry C. 122:22897-22902
ISSN: 1932-7455
1932-7447
Popis: We investigate the kinetics of elemental segregation during the synthesis of Cu(In1−x,Gax)Se2 (CIGS) thin films via a rapid thermal growth process. Changes in elemental concentration are mapped rapidly via in situ X-ray fluorescence (XRF) microscopy. In situ XRF enables the quantification of Cu, In, Ga, and Se concentrations with 200 nm spatial resolution over a region of 7 μm × 7 μm, large enough to map multiple CIGS grains. Reacting elemental precursor stacks at 500, 550, and 600 °C, we find that copper is the driving force for α-CIGS phase formation at a rate of 17 nmol/cm2/min at 500 °C. Because of the thermal expansion of the substrate, cluster analysis and classification algorithms were employed to track compositionally similar regions over time and across samples measured at different temperatures. Beyond the direct application of these results for the optimization of CIGS manufacturing, these in situ experiments demonstrate the feasibility of quantitative compositional evaluation at the nanoscale ...
Databáze: OpenAIRE