Laboratory for Chalcogenide Photovoltaics, Energy and Semiconductor Research Laboratory, Institute of Physics, Carl von Ossietzky University of Oldenburg, Oldenburg, Lower Saxony, Germany.
PLoS One. 2021 Jan 12;16(1):e0245390. doi: 10.1371/journal.pone.0245390. eCollection 2021.
The formation of molybdenum diselenide (MoSe2) 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 MoSe2 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 MoSe2, thin diffusion barrier layers of silicon oxynitride (SiOxNy) 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 MoSe2 layers is achieved. In terms of energy conversion efficiency (η), CZTSe solar cells grown on Mo/SiOxNy back contacts suffer a deterioration as the SiOxNy layers get thicker. CZTSe solar cells grown on Mo/SiOxNy/Mo back contacts preserve their efficiencies at ≈ 11% with thin 10 nm SiOxNy layers.
二硒化钼（MoSe2）的形成在铜锌锡硒（CZTSe）薄膜太阳能电池的背接触界面广泛存在。取决于硒（Se）的供应情况以及在钼（Mo）衬底上形成 CZTSe 吸收体的热条件，MoSe2 的厚度可以从几百纳米到约 1 微米不等，这与通常采用的 1 到 1.5 微米厚的 CZTSe 吸收体相当。在这项研究中，为了控制界面 MoSe2 的厚度，在制备过程中，在生长 CZTSe 吸收体之前，将薄薄的氮化硅氧（SiOxNy）扩散阻挡层沉积在 Mo 层上。结果，MoSe2 层的厚度减少了。就能量转换效率（η）而言，在 Mo/SiOxNy 背接触上生长的 CZTSe 太阳能电池随着 SiOxNy 层变厚而恶化。在 Mo/SiOxNy/Mo 背接触上生长的 CZTSe 太阳能电池在具有 10nm 厚 SiOxNy 层的情况下，效率保持在约 11%。
