Abstract. An indium arsenide photovoltaic cell with gold front contacts is designed for use in a near-field thermophotovoltaic (NF-TPV) device consisting of millimeter-size surfaces separated by a nanosize vacuum gap. The device operates with a doped silicon radiator maintained at a temperature of 800 K. The architecture of the photovoltaic cell, including the emitter and base thicknesses, the doping level of the base, and the front contact grid parameters, is optimized to maximize NF-TPV power output. This is accomplished by solving radiation and charge transport in the cell via fluctuational electrodynamics and the minority charge carrier continuity equations, in addition to accounting for the shading losses due to the front contacts and additional series resistance losses introduced by the front contacts and the substrate. The results reveal that these additional loss mechanisms negatively affect NF-TPV performance in a non-negligible manner and that the maximum power output is a trade-off between shading losses and series resistance losses introduced by the front contacts. For instance, when the cell is optimized for a 1 × 1 mm2 device operating at a vacuum gap of 100 nm, the losses introduced by the front contacts reduce the maximum power output by a factor of ∼2.5 compared with the idealized case when no front contact grid is present. If the optimized grid for the 1 × 1 mm2 device is scaled up for a 5 × 5 mm2 device, the maximum power output is only increased by a factor of ∼1.08 with respect to the 1 × 1 mm2 case despite an increase of the surface area by a factor of 25. This work demonstrates that the photovoltaic cell in a NF-TPV device must be designed not only for a specific radiator temperature but also for a specific gap thickness and device surface area.

中文翻译：

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用于近场热光伏器件的砷化铟电池的设计

摘要。具有金前触点的砷化铟光伏电池设计用于近场热光伏 (NF-TPV) 设备，该设备由由纳米级真空间隙隔开的毫米级表面组成。该器件使用温度保持在 800 K 的掺杂硅辐射器工作。光伏电池的架构，包括发射极和基极厚度、基极掺杂水平和前接触栅极参数，都经过优化，以最大限度地提高 NF- TPV 功率输出。这是通过通过波动电动力学和少数电荷载流子连续性方程求解电池中的辐射和电荷传输来实现的，此外还要考虑由于前触点和由前触点和基板引入的附加串联电阻损耗造成的遮蔽损失。结果表明，这些额外的损耗机制以不可忽略的方式对 NF-TPV 性能产生负面影响，并且最大功率输出是前触点引入的遮蔽损耗和串联电阻损耗之间的权衡。例如，当电池针对在 100 nm 真空间隙下运行的 1 × 1 mm2 器件进行优化时，与没有前部的理想情况相比，前部触点引入的损耗使最大功率输出降低了约 2.5 倍。存在接触网格。如果将 1 × 1 mm2 器件的优化网格放大到 5 × 5 mm2 器件，尽管表面积增加，但相对于 1 × 1 mm2 的情况，最大功率输出仅增加了约 1.08 倍面积乘以 25。