【作者】 陈斌；

【导师】 杜国平；

【作者基本信息】 南昌大学 ， 材料物理与化学， 2012， 硕士

【摘要】 目前,晶体硅太阳能电池生产已经趋向于薄片化,目的是降低电池成本,为了降低非平衡载流子在扩散过程中的复合率,因此硅太阳电池背表面的处理在太阳电池生产制造中占有极为重要的地位¨。本文通过配制一种新型的硅基太阳电池背场用硼铝导电浆来改善现存铝导电浆的不足,通过电池性能的测试及对比,印证了该新型铝硼导电浆的优越性能。首先,利用四点探针测试仪、Ⅰ-Ⅴ曲线测试仪及二次离子质谱(SIMS)研究分析了背表面场的制备工艺对单晶硅背表面的方块电阻和掺杂浓度及太阳电池电池光电转换效率等电学性能的影响。相较于常规铝导电浆制备的背表面场,新型铝硼导电浆制备的单晶硅背表面场的各项电学性能都得到了优化；当热处理温度为850。C时,铝硼导电浆(铝硼合金粉中硼含量为1wt%)制备的铝背场最大掺杂浓度大约为4.21×1019atoms/cm3,而常规铝导电浆的最大掺杂浓度只有3.05×1018atoms/cm3,同时太阳电池铝背场的方块电阻从11.63Ω/(?)降低到了5.22Ω/(?),此时单晶硅太阳电池的开路电压、短路电流密度、填充因子及光电转换效率都得到提高。随着硼含量的增加和热处温度的提高,单晶硅铝背场的方块电阻都呈现下降趋势。然后,采用扫描电子显微镜(SEM)对不同工艺制备的单晶硅铝背场表面及截面形貌的进行表征及分析。通过SEM图片我们发现,在磁控溅射制备铝背场的过程中,需要得到致密的导电铝层,在单晶硅背表面中铝膜的溅射厚度必须要大于1μm；同时总结了不同的铝膜溅射厚度制备的铝背场的表面形貌的变化及规律；观察还得到了采用丝网印刷硼铝导电浆所制备的太阳电池背表面场、铝硅硼合金层及铝层的厚度分布情况。最后,通过透射电镜(TEM)对丝网印刷制备的铝硼背场和铝硼硅合金接触面形貌及铝层内部颗粒结构进行观察分析。更多还原

【Abstract】 At present, the production of crystalline silicon solar cells tends to use thinner silicon wafers. The purpose is to reduce the cost and recombination of non-equilibrium carriers in the diffusion process, so the treatment of back surface field (BSF) plays an extremely important role in the solar cell manufacturing. In this work, in order to improve the deficiencies of the conventional aluminum conductive paste, a new type of aluminum boron conductive paste used for solar cells BSF is prepared. Testing and comparison of solar cells performance confirms the superiority of the new aluminum boron conductive paste.Firstly, through four-point probe measurements, the IV curve test instrument and secondary ion mass spectrometry (SIMS), we measured the electrical properties of the back surface field, the doping concentration in the BSF, and the photovoltaic properties of solar cells. Compared with the back surface field prepared by the conventional aluminum conductive paste, the electrical properties of the back surface field prepared by the new aluminum boron conductive paste were improved. When the BSF was sintered at850℃, the alloyed aluminum boron conductive paste with the B content at1.0wt%in Al-B alloy powders, the B concentration reached about4.21×1019atoms/cm3within the BSF, while the highest Al concentration was about3.05x1018atoms/cm3. Meanwhile the BSF sheet resistance was11.6Ω/□for the paste without containing B, and it quickly dropped to about5.2Ω/□for B at1.0wt%. In the meantime, the open circuit voltage, short circuit current density and fill factor of monocrystalline silicon solar cell were improved. Along with the increase of boron content and sintering temperature, the sheet resistance of monocrystalline aluminum back surface field has showed a downward trend.Secondly, we used scanning electron microscopy (SEM) to characterize and analyze the surface and cross section morphologies of the back surface field. Through these SEM images, we found that the sputtering thickness of the aluminum must be greater than1μm to make sure that we had a dense conductive aluminum layer in the process of magnetron sputtering back surface field. The variation of the morphology of the back surface field along with the thickness of sputtering aluminum was studied.Finally, We used transmission electron microscopy (TEM) to observe and analyze the microstructures of back surface field and Al-Si alloy, and the particle structure within the aluminum electrode.更多还原