We describe the optimization of an ultra-thin silicon oxynitride (SiO_xN_y) layer deposited by plasma enhanced chemical vapor deposition (PECVD) as an interfacial layer for phosphorus doped polysilicon (poly-Si) passivating contacts. Our results demonstrate the possibility of depositing the thin interfacial layer and the intrinsic amorphous silicon (a-Si) film in a single PECVD process. We found that the gas flow rates strongly influence the properties of the SiO_xN_y layers, such as the refractive indices, chemical bond compositions and structural stabilities, which significantly affect the properties of the resulting polysilicon passivating contact structures. The passivation quality initially increased and then decreased with a decreasing N₂O/SiH₄ flow ratio, in the gas flow range of uniform deposition, while the contact resistivity decreased significantly. We found an optimal gas flow ratio of N₂O:SiH₄:N₂ = 25:9:361, with which we obtained uniform polysilicon passivating contacts with a high implied open-circuit voltage (iV_oc) of 711 mV and a low contact resistivity ρ_c of 6.6 mΩ cm².

我们描述了通过等离子体增强化学气相沉积 (PECVD) 沉积的超薄氮氧化硅 (SiO _x N _y ) 层作为掺磷多晶硅 (poly-Si) 钝化触点的界面层的优化。我们的结果证明了在单个 PECVD 工艺中沉积薄界面层和本征非晶硅 (a-Si) 膜的可能性。我们发现气体流速对 SiO _x N _y的性质有很大影响层，例如折射率、化学键组成和结构稳定性，它们显着影响所得多晶硅钝化接触结构的性能。在均匀沉积的气体流量范围内，随着N ₂ O/SiH ₄流量比的减小，钝化质量先升高后降低，而接触电阻率显着降低。我们发现了 N ₂ O:SiH ₄ :N ₂  = 25:9:361的最佳气体流量比，由此我们获得了具有711 mV的高隐含开路电压 ( iV _oc ) 和低的均匀多晶硅钝化触点。6.6 mΩ cm 的接触电阻率ρ _c² .