Record Efficiency Photovoltaic Heterostructures

在过去的3年里，Fafard的团队在光电器件方面取得了突破性的进展，目前在任何类型的器件中都具有最高的光到电转换效率。最近在几次受邀的国际演讲和最新的科学论文中介绍了这一进展。最近在先进III-V异质结构领域的发展使得实现大于65%的光电转换效率。目前的建议是进一步推进对这些新型III-V半导体光换能器的理解和发展。记录效率器件基于一种新颖的垂直外延异质结构（VEHSA）设计。由于通过金属有机化学气相沉积外延或化学束外延生长的薄半导体层的精确控制，可以通过适合各种应用的定制输出电压获得前所未有的性能。因此，提出的研究是在纳米级p/n结领域，并将揭示超薄基底光伏器件的非常有趣的特性，包括光子回收效应。异质结构设计为实验研究的所有结构提供了高外量子效率（EQE）值，迄今为止多达20个超薄亚电池（PT20器件）。所有结构的转换效率都超过60%，包括最近的pt20。此外，这些高效率可以保持高电输出功率，达到大于3W的芯片只有几毫米

In the past 3 years, Fafard’s team made breakthrough optoelectronic device advancements, now featuring the highest optical to electrical conversion efficiency ever for any type of devices. The progress has been presented recently at several invited international presentations and late-news scientific papers. This recent development in the area of advanced III-V heterostructures allowed attaining greater than 65% optical to electrical conversion efficiencies. The current proposal is to further advance the understanding and the development with these novel III-V semiconductor phototransducers. The record-efficiency devices are based on a novel vertical epitaxial heterostructure architecture (VEHSA) design. Thanks to a precise control of thin semiconductor layers grown by Metal-Organic Chemical Vapor Deposition epitaxy or by chemical beam epitaxy, the unprecedented performance can be obtained with tailored output voltages adapted for various applications. The proposed research is therefore in the area of nanoscale p/n junctions and will reveal very interesting properties for photovoltaic devices engineered with ultra-thin bases, including photon recycling effects. The heterostructure designs yielded high external quantum efficiency (EQE) values for all the structures studied experimentally, up to 20 ultra-thin subcells (PT20 devices) to date. Conversion efficiencies greater than 60% were confirmed for all structures, including recently the PT20s. Additionally, these high efficiencies can be maintained for high electrical output powers, reaching greater than 3W for chips only a few mm