正型鍺之鈀金歐姆接觸結構及其應用於雙結太陽能電池之研究

Study of Pd/Au Ohmic Contact on P-Type Ge and Its Application to GaAs/Ge Dual-Junction Solar Cells

楊智超(Chih-Chao Yang)

中原大學/工學院/電子工程研究所/碩士(2011年)

https://doi.org/10.6840/CYCU.2011.00203

摘要

摘要 在本論文中，我們將會先從探討鈀的厚度在鈀/金以及鈀/銀/金沉積在正型鍺當作歐姆接觸金屬結構之影響，為了得到最低的特徵阻值ρc，我們尋求最佳之鈀的金屬厚度還有最佳的回火條件，並且運用傳輸線模型法(TLM)計算出鈀/金金屬材料在正型鍺的特徵阻值。實驗結果顯示，在鍺(30nm)/金(60nm)在350℃兩分鐘的回火條件下，能夠形成此系列之最佳特徵阻值( ρc=6×10-6 Ω-cm2 )。接著，利用相同方式找尋鈀/銀/金金屬材料在正型鍺的特徵阻值，發現當鈀(20nm)/銀(60nm)/金(20nm) 在350℃兩分鐘的回火條件下，也能形成此系列之最佳特徵阻值 ( ρc=3.9×10-5 Ω-cm2 )。 緊接著，將具有最低特徵阻值的歐姆接觸金屬組成結構(亦即鈀 (30nm)/金(60nm)以及鈀(20nm)/銀(60nm)/金(20nm)) 蒸鍍在雙接面(GaAs/Ge)太陽能電池當作背電極，來探討鈀/金姆接觸金屬材料應用於元件上之後的元件特性，如同歐姆接觸金屬蒸鍍在正型鍺基板上的結果，太陽能電池的效率(Eff)、填充因子(FF)、短路電流(Isc)、開路電壓(Voc)皆在最佳歐姆接觸金屬組成的最佳條件下有最好的表現。

關鍵字

毆姆接觸 ； 鈀/金

並列摘要

Abstract
In this dissertation, we discussed the effects of thickness Pd on the Pd / Au and Pd / Ag / Au ohmic contact metallurgical structure deposited on P-Ge material. At first ,we studied the optimum thickness of the Pd layer and the suitable annealing temperature and time for obtaining the lowest specific contact resistance ρc on P-Ge by transmission line model method (TLM).We found out that the optimum metallurgical structure is Pd (30 nm) / Au (60 nm) after annealed at 350 ℃ for 2 minutes. The lowest value ρc=6×10-6 Ω-cm2 of specific contact resistance could be attained. Then, we used the same method to study the optimum thickness of the Pd、Ag and Au layers and the suitable annealing temperature and time for the lowest specific contact resistance ρc. We found out that the optimum metallurgical structure is Pd (20 nm) / Ag (60 nm) / Au (20 nm), in which the lowest specific contact resistance value ρc=3.9×10-5 Ω-cm2 could be attained when the sample is annealed at 350℃ for 2 minutes.
Then, we applied the optimum ohmic contact metallurgical structure Pd (30 nm) /Au (60 nm) and Pd (20 nm) / Ag (60 nm) / Au (20nm), respectively, as the p-type ohmic contact of dual-junction (DJ) solar cells. After that, we measured the efficiency (Eff), fill factor (FF), open circuit voltage (Voc) and short circuit current (Isc) of solar cells. The measured results indicate that solar cells had the best performance when having the ohmic contact fabricated at the optimum conditions.

並列關鍵字

ohmic contact ； Pd/Au

參考文獻

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