For optimizing the performance of tungsten oxide (WO_x)/c-Si heterojunction solar cells, it is important to understand the carrier transport process within the device. Recently, several studies examined transport mechanisms; but yet reported not apparently. In this study, the fundamental carrier transport mechanisms in WO_x/c-Si heterojunction solar cells and their effects on the device characteristics are investigated. Our results indicate that the trap-assisted-tunneling (TAT) process is the dominant carrier transport mechanism in the forward-bias voltage regime, while the generation of current in the space-charge region is dominant in the reverse-bias voltage regime. Interestingly, it was found that the hole-selective contact with lower oxygen-to-tungsten ratios, which is related to that of high trap densities, can assist the TAT process and increase the fill factor of the device regardless of the film conductivity. This finding is inconsistent with those of previous experiments but is consistent with those of previous simulations. Finally, this confirmation can help with optimization of WO_x/c-Si heterojunction solar-cell efficiencies.

为了优化氧化钨（WO _x）/ c-Si异质结太阳能电池的性能，重要的是要了解器件内的载流子传输过程。最近，一些研究检查了运输机制。但尚未见报道。在这项研究中，WO _x中的基本载流子传输机制研究了/ c-Si异质结太阳能电池及其对器件特性的影响。我们的结果表明，陷阱辅助隧穿（TAT）过程是正向偏压状态下的主要载流子传输机制，而空间电荷区中的电流生成在反向偏压状态下是主要的。有趣的是，发现与高陷阱密度相关的具有较低氧钨比的空穴选择性接触可以协助TAT工艺并增加器件的填充系数，而与薄膜电导率无关。该发现与先前的实验不一致，但是与先前的模拟一致。最后，此确认可以帮助优化WO _x/ c-Si异质结太阳能电池效率。