表面鈍化用於增強太陽能電池的性能是必要的過程，在所有的鈍化材料中，氧化鋁(Al2O3)已證實為優質的鈍化層，基於其高密度的固定負電荷。本研究使用陽極氧化法所形成的氧化鋁，製備出局部背面接觸（PERC）的矽晶太陽能電池，並以鋁漿直接燒穿方式取代傳統的雷射開孔。
首先，藉由尋找最佳化的陽極氧化時間、熱退火溫度、熱退火時段等參數，使氧化鋁層在矽表面上表現完美的場效鈍化能力，為了探討氧化鋁退火前與退火後的材料特性，由C-V測量來分析其負電荷密度，利用XPS與TEM來量測其元素的組成與薄膜的型態。
最後，歸因於Al2O3鈍化太陽能電池背面的良好特性，與圖案的鋁漿背接觸做整合，此局部背面接觸的太陽能電池，其最佳的填充因子F.F.為73.1%、轉換效率為16.13%，與參考片電池相比其效率提升0.21%。

Surface passivation is the essential process for enhancing the performance of silicon solar cells. Among all the passivation materials, aluminum oxide (Al2O3) has proved to be a high quality passivationmaterial due to its high density of negative fixed charges. In this study, we form the Al2O3 film by anodization and apply this passivation layer onto the rear side of PERC solar cell. Moreover, the aluminum back contact are formed by making aluminum electrode penetrate the Al2O3 layer at high temperature instead of the conventional laser ablation process.
By finding the optimum anodization time period, thermal annealing temperature and annealing time, Al2O3 layer shows a perfect field-effect passivation on the silicon surface. In order to investigate the material characteristics of Al2O3 before and after annealing, the negative charge density is analyzed by C-V measurement. Then, the elemental composition and the film thickness are measured by XPS and TEM, respectively.
Finally, we integrate the Al2O3 rear passivation effect with a patterned aluminum paste back contact in fabricating a PERC multi-crystalline silicon solar cell. The PERC solar cell shows a fill facor of 73.1% and a conversion efficiency of 16.13%, which gives an efficiency improvement of 0.21% absolute in comparison with the reference cell.

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