氮化銦鎵的能隙範圍涵蓋大部分的太陽光譜，若以此種三元化合物製作太陽能電池，在理論上可達到幾近全光譜的吸收，產生極高的能量轉換效率。在吸光層結構的設計中，氮化銦鎵/氮化鎵多重量子井是很受歡迎的一種，這是因為氮化銦鎵量子井具備兼顧晶格品質及可見光吸收能力的優點。有鑑於矽基板的低成本與良好的散熱性，我們使用金屬有機化學氣相沉積法，在矽基板上成長氮化銦鎵多重量子井太陽能電池。 在本篇研究中，我們製作了三種不同銦含量的氮化銦鎵/氮化鎵多重量子井太陽能電池。在AM 1.5G的模擬光源照射下，元件的轉換效率最高為0.133%；而當聚光倍率增加為105倍時，轉換效率可達0.168%，效率提升幅度則是接近23%，此效率提升可歸功於矽基板良好的散熱性。 在元件的製程上，我們也探討Ni/Au透明導電層及n-GaN蝕刻深度對元件特性的影響。就量測結果來看，Ni/Au透明導電層能幫助元件蒐集光電子，而適當的n-GaN蝕刻深度，則能幫助電池得到較高的填充因子。 The wide bandgap span (0.7 – 3.4 eV) of InGaN has drawn increasing research interest in photovoltaics due to its potential to realize nearly full absorption of the entire solar spectrum. In the structure design for light-absorbing layers, InGaN/GaN multiple quantum wells (MQW) are among the most popular because of their superior crystal qualities and visible-wavelength absorption capabilities. In light of the low cost and the excellent heat dissipation of silicon substrates, we have grown and fabricated InGaN-based MQW solar cells on silicon substrates using metal organic chemical vapor deposition. In this project, we studied three types of InGaN/GaN MQW solar cells with different indium contents. The highest conversion efficiency was 0.133% under the illumination of AM 1.5G. As the concentration ratios increased from 1-sun to 105-sun, the efficiency went up to 0.168%. The result was attributed to the efficient heat sinking of the Si substrate. In addition, we also investigated the effects of Ni/Au transparent conductive layer and the etching depth of n-GaN on the performances of the devices. The results indicate that the transparent conductive layer is beneficial to carrier collection efficiencies, and a proper etching depth of n-GaN can maximize the fill factor of the solar cells.
