报道了管式等离子体增强化学气相沉积（PECVD）的各项沉积参数对硅太阳电池重掺杂多晶硅钝化接触（SiOx/Poly-Si（n+））的影响。TOPCon太阳电池的掺杂多晶硅是通过对沉积的非晶硅高温晶化来实现的,通过改变PECVD的沉积温度、Ar和PH3的流量、沉积功率等沉积参数,可获得不同厚度、结晶度和掺杂浓度的掺杂非晶硅（a-Si（n+））薄膜,然后通过高温退火得到不同的Poly-Si（n+）薄膜,从而导致SiOx/Poly-Si（n+）钝化接触在钝化质量和载流子选择性等方面的不同特性。最后在沉积温度480 ℃、Ar流量8 L/min、PH3流量0.8 L/min、沉积功率12000 W、退火温度920 ℃的条件下获得最佳双面SiOx/Poly-Si（n+）/SiNx钝化接触,少子寿命达到6445 μs,隐含开路电压（iVoc）达到742.7 mV以上,单面饱和电流密度J0低至4.2 fA/cm2。
Abstract
The effects of deposition parameters of tube plasma enhanced chemical vapor deposition （PECVD） on the heavily doped polysilicon passivated contact （SiOx/Poly-Si（n+）） of silicon solar cells are reported. The doped polysilicon of TOPCon solar cells is achieved by high temperature crystallization of deposited amorphous silicon. a-Si （n+） films with different thickness, crystallinity and doping concentration can be obtained by changing the deposition temperature, the flow rate of Ar and PH3, deposition RF power and other deposition parameters of PECVD. Then different Poly-Si（n+） films are obtained by annealing at high temperature, resulting in different characteristics of SiOx/Poly-Si（n+） passivated contact in terms of passivating quality and carrier selectivity. Finally, under the deposition temperature of 480 °C, Ar flow rate of 8 L/min, PH3 flow rate of 0.8 L/min, deposition RF power of 12000 W, annealing temperature of 920℃, the optimal double-side SiOx/Poly-Si（n+）/SiNx passivated contact is obtained. The minority lifetime reaches to 6445 μs, the implied open circuit voltage （iVoc） reaches to 742.7 mV, and the single-side saturation current density J0 is as low as 4.2 fA/cm2.
关键词
硅基太阳电池 /
钝化 /
多晶硅 /
掺杂 /
等离子增强化学气相沉积
Key words
silicon solar cells /
passivation /
polycrystalline silicon /
doping /
plasma enhanced chemical vapor deposition
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参考文献
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