Open AccessSiOxNy back-contact barriers for CZTSe thin-film solar cells
Author(s) -
Wenjian Chen,
Hippolyte Hirwa,
J. Ohland,
Teoman Taskesen,
Ulf Mikolajczak,
Devendrá Pareek,
J. Parisi,
Levent Gütay
Publication year - 2021
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0245390
Subject(s) - materials science , thin film , molybdenum , fabrication , silicon , layer (electronics) , solar cell , nanotechnology , energy conversion efficiency , czts , copper indium gallium selenide solar cells , diffusion barrier , optoelectronics , metallurgy , medicine , alternative medicine , pathology
The formation of molybdenum diselenide (MoSe 2 ) is widely observed at the back-contact interface for copper zinc tin selenide (CZTSe) thin-film solar cells. Depending on individual selenium (Se) supply and thermal conditions for forming CZTSe absorbers on molybdenum (Mo) substrates, the thickness of MoSe 2 can vary from a few hundreds of nanometers up to ≈ 1 μm, which is comparable to the commonly adopted thickness of 1 ~ 1.5 μm for CZTSe absorbers. In this study, for controlling the thickness of interfacial MoSe 2 , thin diffusion barrier layers of silicon oxynitride (SiO x N y ) are deposited onto Mo layers prior to the growth of CZTSe absorbers in the fabrication process. As a result, a reduction in the thicknesses of MoSe 2 layers is achieved. In terms of energy conversion efficiency ( η ), CZTSe solar cells grown on Mo/SiO x N y back contacts suffer a deterioration as the SiO x N y layers get thicker. CZTSe solar cells grown on Mo/SiO x N y /Mo back contacts preserve their efficiencies at ≈ 11% with thin 10 nm SiO x N y layers.