Back contact transparent conductive electrodes are essential components of semi-transparent perovskite solar cells, which are especially beneficial for tandem photovoltaics. In this Letter, we present a way to realize ultrathin metal layers in ITO-metal-ITO (IMI) electrode stacks, which are characterized by the superior infrared transmittance and electrical conductivity. The metal layers are deposited by the co-sputtering technique, which enables the realization of smooth metallic films, as thin as 5 nm. We applied the IMI electrodes to flexible high bandgap perovskite solar cells and demonstrated that the IMI electrodes based on the co-sputtered metals are outperforming the standard ITO electrodes in terms of cell performance, while maintaining similar transmission values. Furthermore, we show that the IMI electrodes are significantly more flexible than the standard ITO and, thus, are more suitable for flexible optoelectronic devices. The co-sputtering technique is compatible with the industrial production process. Overall, the co-sputtered IMI stack presented in this work paves the way for the commercial utilization of semi-transparent (visible or near-infrared range) photovoltaic devices, including high-efficiency tandem applications and window-integrated photovoltaics.

中文翻译：

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基于共溅射超薄金属层的透明导电电极用于半透明钙钛矿太阳能电池

背接触透明导电电极是半透明钙钛矿太阳能电池的重要组成部分，特别有利于串联光伏。在这封信中，我们提出了一种在 ITO-金属-ITO (IMI) 电极堆叠中实现超薄金属层的方法，其特点是具有优异的红外透射率和导电性。金属层通过共溅射技术沉积，可实现薄至 5 nm 的光滑金属薄膜。我们将 IMI 电极应用于柔性高带隙钙钛矿太阳能电池，并证明基于共溅射金属的 IMI 电极在电池性能方面优于标准 ITO 电极，同时保持相似的透射值。此外，我们表明 IMI 电极明显比标准 ITO 更灵活，因此更适用于柔性光电器件。共溅射技术与工业生产过程兼容。总的来说，这项工作中提出的共溅射 IMI 堆栈为半透明（可见光或近红外范围）光伏器件的商业利用铺平了道路，包括高效串联应用和窗口集成光伏器件。