摘 要
本文探討在藍寶石基板上成長具有超晶格結構作為吸收層之光伏元件，其於照光情況下，光載子的傳輸特性與材料品質相關且載子生命期也主導光伏元件的電流收集效率。本研究之元件磊晶層成長在藍寶石基板後，於製程時設計不同的元件平台高度，來探討具有高缺陷密度n+-GaN層的等效厚度對元件特性之影響。初步結果顯示，當平台高度為300奈米時，其元件光電轉換效率與平台高度為1000奈米的元件比較起來約可提升35%。
關鍵詞：光伏、氮化銦鎵、電流收集
Abstract
InGaN-based photovoltaic devices that incorporate a p-i-n design with GaN/InGaN superlattice absorption layers epitaxially grown on sapphire substrates by metal-organic vapor phase epitaxy techniques are produced. The stacked superlattice structure with thin barrier and well layers is applied and used as the absorption layer. Since the carrier lifetime can dramatically dominate the current collection’s efficiency of a photovoltaic device, the devices are designed in this study to have different mesa heights for evaluating the effect of effective thickness of n+-GaN layer with high-density defects (i.e., short diffusion length of carriers) on device performance. The conversion efficiency of the devices with a mesa height as low as 300 nm can be improved by around 35% as compared to that of devices with a mesa height of 1000 nm.
Keywords: Photovoltaic, InGaN, Current Collection.