0000000000955214
AUTHOR
D. Kieven
Preparation and properties of radio-frequency-sputtered half-Heusler films for use in solar cells
Abstract The class of half-Heusler compounds opens possibilities to find alternatives for II–VI or III–V compound semiconductors. We aim to find suitable substitutes for the cadmium sulphide buffer layer in chalcopyrite-based thin film solar cells, where the buffer layer is located between the p-type chalcopyrite absorber and an n-type transparent window layer. We report here the preparation of radio-frequency-sputtered lithium copper sulphide “LiCuS” and lithium zinc phosphide “LiZnP” films. The optical analysis of these films revealed band gaps between 1.8 and 2.5 eV, respectively. Chemical properties of the film surface and both interfaces between the film and a Cu ( In , Ga ) Se 2 layer…
I-II-V half-Heusler compounds for optoelectronics:Ab initiocalculations
Half-Heusler compounds $XYZ$ crystallize in the space group $F\overline{4}3m$ and can be viewed as a zinc-blende-like ${(YZ)}^{\ensuremath{-}}$ lattice partially filled with He-like ${X}^{+}$ interstitials. In this work, we investigated I-II-V (eight-electrons) half-Heusler compounds by first-principles calculations in order to find suitable semiconductors for optoelectronics such as Cd-free buffer layer materials for chalcopyrite-based thin-film solar-cell devices. We report a systematic examination of band gaps and lattice parameters, depending on the electronegativities and the ion radii of the involved elements. Half-Heusler buffer materials should have a band gap of more than 2 eV to a…