本文中应用全部PECVD工艺沉积a-SiOx:H、a-SiNx:H,和a-SiOx:H/a-SiNx:H叠层系统,比较了不同钝化膜对多晶硅太阳能电池发射极和背面钝化效果,应用FGA、RTP等热处理方法对钝化膜进行处理,重点讨论了FGA(Forming gas annealing)温度和时间...本文中应用全部PECVD工艺沉积a-SiOx:H、a-SiNx:H,和a-SiOx:H/a-SiNx:H叠层系统,比较了不同钝化膜对多晶硅太阳能电池发射极和背面钝化效果,应用FGA、RTP等热处理方法对钝化膜进行处理,重点讨论了FGA(Forming gas annealing)温度和时间的长短对钝化的影响。结果表明:低温FGA对只有单面钝化膜的硅片钝化效果不明显,而在800℃下FGA有明显作用,而且钝化效果随着时间的增加呈现出先增大后减小然后再增大的现象;退火后降温环境中是否有H和降温时间对钝化效果有很大的影响,但是对于双面膜无论FGA温度高低对钝化都有帮助,文中对上述现象做了合理的解释。最后利用双面叠层钝化膜经过FGA处理后得到的多晶硅片的少子寿命达到14.2μs,比镀膜之前的3.0μs提高了11.2μs,使多晶硅太阳能电池暗电压Voc达到630mV。展开更多
We investigate a passivation scheme using hydrogenated amorphous silicon suboxide （a-SiOx ：H） film for industrial solar cell application. The a-SiOx ：H films were deposited using plasma-enhanced chemical vapor dep...We investigate a passivation scheme using hydrogenated amorphous silicon suboxide （a-SiOx ：H） film for industrial solar cell application. The a-SiOx ：H films were deposited using plasma-enhanced chemical vapor deposition （PECVD） by decomposing nitrous oxide, helium and silane at a substrate temperature of around 250 ℃. An extensive study has been carried out on the effect of thermal annealing on carrier lifetime and surface recombination velocity, which affect the final output of the solar cell. Minority carrier lifetimes for the deposited a-SiOx ：H films without and with the thermal annealing on 4 Ω-cm p-type float-zone silicon wafers are 270 μs and 670μs, respectively, correlating to surface recombination velocities of 70 cm/s and 30 cm/s. Optical analysis has revealed a distinct decrease of blue light absorption in the a-SiOx ：H films compared to the commonly used intrinsic amorphous silicon passivation used in solar cells. This paper also reports that the low cost and high quality passivation fabrication sequences employed in this study are suitable for industrial processes.展开更多
A set of a-SiOx:H (0.52 <x< 1.58) films are fabricated by plasma-enhanced-chemical-vapor-deposition (PECVD) method at the substrate temperature of 250°C. The microstructure and local bonding configurations ...A set of a-SiOx:H (0.52 <x< 1.58) films are fabricated by plasma-enhanced-chemical-vapor-deposition (PECVD) method at the substrate temperature of 250°C. The microstructure and local bonding configurations of the films are investigated in detail using micro-Raman scattering, X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). It is found that the films are structural inhomogeneous, with five phases of Si, Si2O:H, SiO:H, Si2O3:H and SiO2 that coexist. The phase of Si is composed of nonhydrogenated amorphous silicon (a-Si) clusters that are spatially isolated. The average size of the clusters decreases with the increasing oxygen concentration x in the films. The results indicate that the structure of the present films can be described by a multi-shell model, which suggests that a-Si cluster is surrounded in turn by the subshells of Si2O:H, SiO:H, Si2O3:H, and SiO2.展开更多
文摘本文中应用全部PECVD工艺沉积a-SiOx:H、a-SiNx:H,和a-SiOx:H/a-SiNx:H叠层系统,比较了不同钝化膜对多晶硅太阳能电池发射极和背面钝化效果,应用FGA、RTP等热处理方法对钝化膜进行处理,重点讨论了FGA(Forming gas annealing)温度和时间的长短对钝化的影响。结果表明:低温FGA对只有单面钝化膜的硅片钝化效果不明显,而在800℃下FGA有明显作用,而且钝化效果随着时间的增加呈现出先增大后减小然后再增大的现象;退火后降温环境中是否有H和降温时间对钝化效果有很大的影响,但是对于双面膜无论FGA温度高低对钝化都有帮助,文中对上述现象做了合理的解释。最后利用双面叠层钝化膜经过FGA处理后得到的多晶硅片的少子寿命达到14.2μs,比镀膜之前的3.0μs提高了11.2μs,使多晶硅太阳能电池暗电压Voc达到630mV。
文摘We investigate a passivation scheme using hydrogenated amorphous silicon suboxide （a-SiOx ：H） film for industrial solar cell application. The a-SiOx ：H films were deposited using plasma-enhanced chemical vapor deposition （PECVD） by decomposing nitrous oxide, helium and silane at a substrate temperature of around 250 ℃. An extensive study has been carried out on the effect of thermal annealing on carrier lifetime and surface recombination velocity, which affect the final output of the solar cell. Minority carrier lifetimes for the deposited a-SiOx ：H films without and with the thermal annealing on 4 Ω-cm p-type float-zone silicon wafers are 270 μs and 670μs, respectively, correlating to surface recombination velocities of 70 cm/s and 30 cm/s. Optical analysis has revealed a distinct decrease of blue light absorption in the a-SiOx ：H films compared to the commonly used intrinsic amorphous silicon passivation used in solar cells. This paper also reports that the low cost and high quality passivation fabrication sequences employed in this study are suitable for industrial processes.
基金This work was supported by the National Natural Science Foundation of China (Grant Nos. 69976028, 29890217) the State Key Development Program of Basic Research of China (Grant No. 2000028201).
文摘A set of a-SiOx:H (0.52 <x< 1.58) films are fabricated by plasma-enhanced-chemical-vapor-deposition (PECVD) method at the substrate temperature of 250°C. The microstructure and local bonding configurations of the films are investigated in detail using micro-Raman scattering, X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). It is found that the films are structural inhomogeneous, with five phases of Si, Si2O:H, SiO:H, Si2O3:H and SiO2 that coexist. The phase of Si is composed of nonhydrogenated amorphous silicon (a-Si) clusters that are spatially isolated. The average size of the clusters decreases with the increasing oxygen concentration x in the films. The results indicate that the structure of the present films can be described by a multi-shell model, which suggests that a-Si cluster is surrounded in turn by the subshells of Si2O:H, SiO:H, Si2O3:H, and SiO2.
