在本論文中，吾人討論不同金屬電極對於氮化銦鎵系列太陽能電池在電性上和功率損失上的影響。利用有機金屬化學氣相沉積系統成長氮化銦鎵系列太陽能電池。吾人設計、製作各種不同指叉電極並計算每一個電極圖型的功率損失。在電極設計中有三根、六根以及十二根類型的指叉電極，將其命名為Therr-Fingers, Six-Fingers, Twelve-Fingers。在電極圖型的設計中，變化指叉的寬度從10μm變化至30μm。由實驗中可以發現太陽能電池的電特性會隨著指叉根數和寬度的減少而變較佳，短路電流密度會隨著指叉電極的根數和寬度減少而增加。開路電壓和填充因子並不會因為不同的電極圖型而有所變化。根據功率損失的計算，金屬電極遮蔽造成的功率損失為最大，依序為片電阻的功率損失、金屬和半導體接面的功率損失、副柵線電極的功率損失和主柵線電極的功率損失在我們設計的指叉電極中。總功率損失會隨著指叉電極的根數和寬度減少而變小。由此可知指叉電極的最佳參數可以從功率損失的計算而獲得，且計算的結果和實際元件的量測有很好的一致性。而最佳的指叉電極為3根其指叉寬度為10μm。並且片電阻的功率損失為影響總功率損失的重要因素之一。片電阻的阻值會直接影響片電阻的功率損失。如能有效地降低片電阻值，以致片電阻的功率損失減少。依據這樣的概念，我們成長了具有較低片電阻的C試片比起原來的A試片。C試片的片電阻為 6.38×104 Ω/□; A試片的片電阻 2.27×105 Ω/□。經由功率損失的計算可得，C試片和A試片的片電阻的功率損失為2.24×10-5 mW/cm2 和1.4×10-4 mW/cm2。當片電阻被改善71%，其功率損失可以被改善84%。
利用功率損失的模擬，我們可以預測不同指叉電極的功率損失和輸出功率並且找尋最佳的指叉電極。由於太陽能電池操作在不同的最大電流情況下，其電極的最佳設計是需要被調整的。利用模擬的方式來討論這個現象，目的是找尋出各別電流下的最佳電極。而操作在不同的最大電流下，應用其最佳化電極，其各別的輸出功率百分比可以達七十以上。

In this thesis, we discuss the influences of various contact patterns on electrical characteristics and power loss for InGaN-based solar cells grown. by Metal organic chemical vapor deposition (MOCVD). Solar cells with various interdigitated electrodes are fabricated and calculated the power loss for each contact pattern. The contact patterns are applied to solar cells with 3, 6 , 12 fingers in a bus bar, denoted as Three-Fingers, Six-Fingers , and Twelve-Fingers. The finger width (wf) is varied from 10 to 30 μm. It is found that decreasing number and width of fingers improve the electrical performance. The short-circuit current density increases with the decreasing number and width of fingers, whereas the open-circuit voltage and fill factor did not significantly vary. According to calculation of power loss, it found that Pshadow is larger than Psheet, Pcontact, Pfinger, and Pbus in these various patterns samples. Total power loss decreases with the finger width and finger number decreasing. Therefore, the best contact pattern is Three-Fingers with finger width of 10μm. The best contact pattern obtained from calculation of power loss is in agreement with that obtained from the electrical analyses. From the calculation of power loss for various contact patterns, Psheet is one of important factors in total power loss. The sheet resistance affects Psheet, and we can decrease the sheet resistance in diffused layer to low the Psheet. From the concept, we grow the sample C with lower sheet resistance compared to sample A. The sheet resistance of sample A is 2.27×105 Ω/□. The sheet resistance of sample C is 6.38×104 Ω/□. From the calculation of sheet resistance loss, Psheet of sample A and sample C is 1.4×10-4 and 2.24×10-5, respectively. When the sheet resistance is improved 71%, and Psheet can be improved 84%.
By simulation of power loss, we can predict the total power loss and power output with various contact patterns, and find optimization of front contact. Since solar cells work at different maximum current density (Jm), the optimization of front contact is need to be adjusted. We will discuss the phenomenon by simulation, in order to find the optimal front contact at each Jm. With the optimization of front contact, the percentage of power output is larger than 70% at each different Jm.

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