title: X-ray fluorescence at nanoscale resolution for multicomponent layered structures: a solar cell case study.
abstract: The study of a multilayered and multicomponent system by spatially resolved X-ray fluorescence microscopy poses unique challenges in achieving accurate quantification of elemental distributions. This is particularly true for the quantification of materials with high X-ray attenuation coefficients, depth-dependent composition variations and thickness variations. A widely applicable procedure for use after spectrum fitting and quantification is described. This procedure corrects the elemental distribution from the measured fluorescence signal, taking into account attenuation of the incident beam and generated fluorescence from multiple layers, and accounts for sample thickness variations. Deriving from Beer-Lambert's law, formulae are presented in a general integral form and numerically applicable framework. The procedure is applied using experimental data from a solar cell with a Cu(In,Ga)Se2absorber layer, measured at two separate synchrotron beamlines with varied measurement geometries. This example shows the importance of these corrections in real material systems, which can change the interpretation of the measured distributions dramatically.
authors.affiliation: School of Electrical, Computer, and Energy Engineering, Arizona State University, 551 E Tyler Mall, Tempe, AZ 85281, USA.
authors.forename: Bradley M
authors.initials: BM
authors.lastname: West
authors.affiliation: School of Electrical, Computer, and Energy Engineering, Arizona State University, 551 E Tyler Mall, Tempe, AZ 85281, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Stuckelberger
authors.affiliation: School for Engineering of Matter, Transport, and Energy, Arizona State University, 551 E Tyler Mall, Tempe, AZ 85281, USA.
authors.forename: April
authors.initials: A
authors.lastname: Jeffries
authors.affiliation: School of Electrical, Computer, and Energy Engineering, Arizona State University, 551 E Tyler Mall, Tempe, AZ 85281, USA.
authors.forename: Srikanth
authors.initials: S
authors.lastname: Gangam
authors.affiliation: Advanced Photon Source, Argonne National Laboratory, Lemont, IL 60439, USA.
authors.forename: Barry
authors.initials: B
authors.lastname: Lai
authors.affiliation: Advanced Photon Source, Argonne National Laboratory, Lemont, IL 60439, USA.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Stripe
authors.affiliation: Advanced Photon Source, Argonne National Laboratory, Lemont, IL 60439, USA.
authors.forename: Jörg
authors.initials: J
authors.lastname: Maser
authors.affiliation: Advanced Photon Source, Argonne National Laboratory, Lemont, IL 60439, USA.
authors.forename: Volker
authors.initials: V
authors.lastname: Rose
authors.affiliation: Advanced Photon Source, Argonne National Laboratory, Lemont, IL 60439, USA.
authors.forename: Stefan
authors.initials: S
authors.lastname: Vogt
authors.affiliation: School of Electrical, Computer, and Energy Engineering, Arizona State University, 551 E Tyler Mall, Tempe, AZ 85281, USA.
authors.forename: Mariana I
authors.initials: MI
authors.lastname: Bertoni
keywords: CIGS; X-ray fluorescence; multilayered structure; solar cell; thin film characterization