Preparation And Performance Study Of Silicon Nanowires/Silicon Thin Film Heterojunciton Solar Cell

Photovoltaic technology is considered to be the main way of solving theglobal energy crisis and environmental pollution. Currently, expensive costs of thepreparation of silicon-based solar cells make large-scale use of photovoltaic powergeneration become impossible. But nanowire radial junction cells have excellentanti-reflection performance and highly efficient carrier separating mechanism, sothey are considered to have much broad developing prospects for achievinglow-cost and efficient batteries. Therefore, a research of silicon nanowire radialjunction cells has been very meaningful. This paper mainly studies preparationprocess and performance optimization of the silicon nanowires/silicon thin filmheterojunction solar cell.Firstly, metal-assisted chemical etching method was used to prepare siliconnanowire arrays. Then, the plasma enhanced chemical vapor deposition (PECVD)technique was used to prepare the intrinsic and p-type doping hydrogenatedamorphous silicon films for forming the radial p-i-n junction. Finally, in order toconduct and collect carriers, aluminum-doped zinc oxide (AZO) transparentconductive films was deposited on the surface of amorphous silicon films by usingmagnetron sputtering technique. First, in order to prepare amorphous silicon andAZO film of conformal deposition to form the radial cell structure of goodmorphology, the deposition morphology of amorphous silicon and AZO films onnanowires was studied. On the one hand, the influence of silicon nanowire lengthand amorphous silicon deposition time on the deposition morphology ofamorphous silicon films were studied; on the other hand, the influence of AZOdeposition time and potassium hydroxide etching time on the depositionmorphology of AZO films were studied, and the optical properties of siliconnanowire arrays was discussed by uv-visible spectrophotometer. thereby, theoptimal preparation plan of radial cell structure has been determined. Furthermore,in order to reduce the carrier recombination of heterojunction interface, based onthe existing equipment, by changing the concentration of the silane and thedeposition pressure and other deposition parameters influenced the properties ofthe intrinsic film, a series of intrinsic hydrogenated amorphous silicon film wasprepared, and a series of characterization methods were used for characterizationthe properties of thin films and the influence of different process parameters on thefilm properties was summarized, therefore the optimal preparation plan of intrinsicthin films has been determined to prepare intrinsic hydrogenated amorphoussilicon film suitable as a passivation layer in solar cell. Finally, based on the previous studies, a series of battery devices were prepared and used to docomparative study. The results have showed that: after adding the intrinsicpassivation layer, the performance of nanotaper battery by potassium hydroxideetching has had greatly improvement.