甚高频高速沉积微晶硅薄膜的研究

采用甚高频化学气相沉积(VHF-PECVD)技术制备了系列微晶硅(μc-Si:H)薄膜样品,重点研究了硅烷浓度、功率密度、沉积气压和气体总流量对薄膜沉积速率和结晶状态的影响,绘制了沉积气压和功率密度双因素相图. 以0.75nm/s的高速沉积了器件质量级的微晶硅薄膜,并以该沉积速率制备出了效率为5.5%的单结微晶硅薄膜电池. 关键词： 微晶硅薄膜 高速沉积 甚高频化学气相沉积     

Preparing Cu2ZnSnS4 films using the co-electro-deposition method with ionic liquids

Cu2ZnSnS4（CZTS） films are successfully prepared by co-electrodeposition in aqueous ionic solution and sulfurized in elemental sulfur vapor ambient at 400 C for 30 min using nitrogen as the protective gas.It is found that the CZTS film synthesized at Cu/（Zn＋Sn）=0.71 has a kesterite structure,a bandgap of about 1.51 eV,and an absorption coefficient of the order of 10 4 cm 1.This indicates that the co-electrodeposition method with aqueous ionic solution is a viable process for the growth of CZTS films for application in photovoltaic devices.     

无铅和少铅的有机-无机杂化钙钛矿太阳电池研究进展

基于有机-无机杂化卤化铅材料的钙钛矿太阳电池的转换效率在短短几年内已迅速突破22%,为未来能源问题的解决带来了曙光,同时也引起了高度重视.但紧随其后的商品化、产业化发展需求极大地增加了对绿色、无毒的高效无铅钙钛矿太阳电池进行研究和开发的重要性和紧迫性.为进一步加快环境友好型钙钛矿太阳电池的研发进度,对目前无铅和少铅钙钛矿太阳电池的发展现状进行了综述.着重讨论了替代元素种类及其浓度、制备工艺等对薄膜和电池性能的影响,以期对电池的工作机理、替代元素的作用机理有更加深刻的认识,为新型环保、高效的钙钛矿太阳电池的制备提供指导.     

ZnO/SnO2复合透明导电膜性能的研究

采用直流磁控溅射工艺在SnO:透明导电玻璃上沉积一层ZnO膜,制备出ZnO/SnO2复合透明导电膜,作为硅薄膜太阳电池前电极.比较了具有不同ZnO厚度的复合膜氢轰击前后的光电性能,发现适当控制ZnO膜的厚度至关重要.研究了快速热退火(RTA)对薄膜的结构及光电性能的影响,发现400℃退火能够改善薄膜的光学性能.     

沉积速率对甚高频等离子体增强化学气相沉积制备微晶硅薄膜生长标度行为的影响

本文采用甚高频等离子体增强化学气相沉积技术制备了沉积速率系列不同生长阶段的微晶硅薄膜,通过椭圆偏振技术研究了生长过程中微晶硅薄膜表面粗糙度的演化.实验结果表明:沉积速率为0.08和0.24nm/s的低速沉积时,硅薄膜表面粗糙度接近,生长指数分别为β=0.21和β=0.20,对应有限扩散生长模式,此时沉积速率对硅薄膜生长影响不大,原因是低速沉积时成膜先驱物有足够时间迁移到能量低的位置;当沉积速率增加到0.66nm/s时,硅薄膜表面粗糙度明显增加,生长指数β=0.81,大于0.5,出现了异常标度行为,与低速沉积的生长模式明显不同,原因是高速沉积时成膜前驱物来不及扩散就被下一层前驱物覆盖,降低了成膜前驱物在薄膜表面的扩散,使表面粗糙度增加和生长指数β增大.β大于0.5的异常标度行为与阴影效应有关.     

高效平面异质结有机-无机杂化钙钛矿太阳电池的质量管理

基于有机-无机杂化钙钛矿材料的太阳电池具有能量转换效率高和制备工艺简单等优点,引起了学术界的高度关注.其中平面异质结结构太阳电池具有结构简单,可与其他类型电池相兼容以构筑叠层电池设计,以及可低温制备等诸多优点,成为当前的一个重要研究方向.然而,电池性能的优劣与钙钛矿薄膜质量的高低有着直接的联系.本文对钙钛矿材料的特性、一步溶液法制备薄膜的成核-生长机理、电池结构的演变等进行了概述,其中重点介绍了高质量钙钛矿薄膜溶液法制备过程的一些最新的质量控制方法;最后对钙钛矿太阳电池的发展及存在问题进行了总结和展望,为今后的研究提供参考.     

微晶硅薄膜的结构及光学性质的研究

借助RF-PECVD辅助RTP技术，采用高沉积气压的技术路线制备了优质的微晶硅薄膜，并利用拉曼光谱、反射谱和透射谱分别研究了微晶硅的晶化率和光学性质.实验中发现微晶硅的吸收边出现了相对红移，此相对红移可归结于薄膜晶化率的提高和带尾态密度的降低. 关键词： 微晶硅 拉曼光谱 快速热处理 红移     

The high deposition of microcrystalline silicon thin film by very high frequency plasma enhanced chemical vapour deposition and the fabrication of solar cells

This paper reports that the intrinsic microcrystalline silicon ($\mu $c-Si:H) films are prepared with plasma enhanced chemical vapour deposition from silane/hydrogen mixtures at 200\du\ with the aim to increase the deposition rate. An increase of the deposition rate to 0.88\,nm/s is obtained by using a plasma excitation frequency of 75\,MHz. This increase is obtained by the combination of a higher deposition pressure, an increased silane concentration, and higher discharge powers. In addition, the transient behaviour, which can decrease the film crystallinity, could be prevented by filling the background gas with Hchemical vapour deposition, plasma deposition, solar cells, crystallinityProgram supported by the State Key Development Program for Basic Research of China (Grant No 2006CB202601), and Basic Research Project of Henan Province in China (Grant No 072300410140).7280N, 7830G, 8115HThis paper reports that the intrinsic microcrystalline silicon ($\mu $c-Si:H) films are prepared with plasma enhanced chemical vapour deposition from silane/hydrogen mixtures at 200\du\ with the aim to increase the deposition rate. An increase of the deposition rate to 0.88\,nm/s is obtained by using a plasma excitation frequency of 75\,MHz. This increase is obtained by the combination of a higher deposition pressure, an increased silane concentration, and higher discharge powers. In addition, the transient behaviour, which can decrease the film crystallinity, could be prevented by filling the background gas with Hchemical vapour deposition, plasma deposition, solar cells, crystallinityProgram supported by the State Key Development Program for Basic Research of China (Grant No 2006CB202601), and Basic Research Project of Henan Province in China (Grant No 072300410140).7280N, 7830G, 8115HThis paper reports that the intrinsic microcrystalline silicon ($\mu $c-Si:H) films are prepared with plasma enhanced chemical vapour deposition from silane/hydrogen mixtures at 200\du\ with the aim to increase the deposition rate. An increase of the deposition rate to 0.88\,nm/s is obtained by using a plasma excitation frequency of 75\,MHz. This increase is obtained by the combination of a higher deposition pressure, an increased silane concentration, and higher discharge powers. In addition, the transient behaviour, which can decrease the film crystallinity, could be prevented by filling the background gas with Hchemical vapour deposition, plasma deposition, solar cells, crystallinityProgram supported by the State Key Development Program for Basic Research of China (Grant No 2006CB202601), and Basic Research Project of Henan Province in China (Grant No 072300410140).7280N, 7830G, 8115HThis paper reports that the intrinsic microcrystalline silicon ($\mu $c-Si:H) films are prepared with plasma enhanced chemical vapour deposition from silane/hydrogen mixtures at 200\du\ with the aim to increase the deposition rate. An increase of the deposition rate to 0.88\,nm/s is obtained by using a plasma excitation frequency of 75\,MHz. This increase is obtained by the combination of a higher deposition pressure, an increased silane concentration, and higher discharge powers. In addition, the transient behaviour, which can decrease the film crystallinity, could be prevented by filling the background gas with Hchemical vapour deposition, plasma deposition, solar cells, crystallinityProgram supported by the State Key Development Program for Basic Research of China (Grant No 2006CB202601), and Basic Research Project of Henan Province in China (Grant No 072300410140).7280N, 7830G, 8115HThis paper reports that the intrinsic microcrystalline silicon ($\mu $c-Si:H) films are prepared with plasma enhanced chemical vapour deposition from silane/hydrogen mixtures at 200\du\ with the aim to increase the deposition rate. An increase of the deposition rate to 0.88\,nm/s is obtained by using a plasma excitation frequency of 75\,MHz. This increase is obtained by the combination of a higher deposition pressure, an increased silane concentration, and higher discharge powers. In addition, the transient behaviour, which can decrease the film crystallinity, could be prevented by filling the background gas with H$_{2}$ prior to plasma ignition, and selecting proper discharging time after silane flow injection. Material prepared under these conditions at a deposition rate of 0.78\,nm/s maintains higher crystallinity and fine electronic properties. By H-plasma treatment before i-layer deposition, single junction $\mu $c-Si:H solar cells with 5.5{\%} efficiency are fabricated.     

Raman散射和AFM对多晶硅薄结晶状况的研究

采用等离子体增强化学气相沉积(PECVD)法在普通玻璃衬底上制备了多晶硅(p-si)薄膜。利用拉曼(Raman)散射谱、原子力显微镜(AFM)研究了衬底温度、射频功率和SiH4浓度对薄膜晶化的影响,并对其结果进行分析讨论。研究结果表明,当衬底温度从200℃逐渐提高到400℃、SiH4浓度从5%降到1%,硅膜的晶化率逐渐提高,结构逐渐由非晶向多晶转变,射频功率对薄膜的晶化状况也有很大影响。     

非晶硅太阳电池宽光谱陷光结构的优化设计

陷光是改善薄膜太阳电池光吸收进而提高其效率的关键技术之一. 以非晶硅（α-Si）薄膜太阳电池为例,设计了一种新的复合陷光结构：在Ag背电极与硅薄膜之间制备一维Ag纳米光栅,并通过保形生长在电池前表面沉积织构的减反膜. 采用有限元数值模拟方法,研究了该复合陷光结构对电池光吸收的影响,并对Ag纳米光栅的结构参数进行了优化. 模拟结果表明：该复合陷光结构可在宽光谱范围内较大地提高太阳电池的光吸收;当Ag纳米光栅的周期P为600 nm,高度H为90 nm,宽度W为180 nm时,在AM1.5光谱垂直入射条件下α-Si薄膜电池在300–800 nm波长范围内总的光吸收较无陷光结构的参考电池提高达103%,其中在650–750 nm长波范围内的光子吸收率提高达300%以上. 结合电场强度分布,对电池在各个波段光吸收提高的物理机制进行了分析. 另外,该复合陷光结构的引入,还较大地改善了非晶硅电池对太阳光入射角度的敏感性. 关键词： 非晶硅太阳电池 陷光 银纳米光栅 数值模拟