1 research outputs found
Grazing Incidence Cross-Sectioning of Thin-Film Solar Cells via Cryogenic Focused Ion Beam: A Case Study on CIGSe
Cryogenic
focused ion beam (Cryo-FIB) milling at near-grazing angles
is employed to fabricate cross-sections on thin CuÂ(In,Ga)ÂSe<sub>2</sub> with >8x expansion in thickness.
Kelvin probe force microscopy (KPFM) on sloped cross sections showed
reduction in grain boundaries potential deeper into the film. Cryo
Fib-KPFM enabled the first determination of the electronic structure
of the Mo/CIGSe back contact, where a sub 100 nm thick MoSe<sub><i>y</i></sub> assists hole extraction due to 45 meV higher work
function. This demonstrates that CryoFIB-KPFM combination can reveal
new targets of opportunity for improvement in thin-films photovoltaics
such as high-work-function contacts to facilitate hole extraction
through the back interface of CIGS