STTR Phase I: P-Type CdSe for Thin-Film Top Cells Enabling High-Efficiency Monolithic Tandem Photovoltaics

STTR 第一阶段：用于薄膜顶部电池的 P 型 CdSe，实现高效单片串联光伏发电

• 批准号: 0320375
• 负责人: Lawrence Woods
• 金额: $ 9.99万
• 依托单位: ITN ENERGY SYSTEMS, INC.
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-07-01 至 2004-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0320375&HistoricalAwards=false
• 关键词: STTR; Phase; Type; CdSe; Thin

This Small Business Technology Transfer (STTR) Phase I project will develop a wide-bandgap, thin-film semiconductor to enable a high-efficiency light-absorber layer for the top cell in monolithic tandem or multi-junction thin-film photovoltaics. Because of relatively high device packaging costs, tandem junction thin-film photovoltaic devices can offer higher watt per square meter and lower cost per watt than their single junction counterparts. In order to overcome the current low thin-film device efficiencies for materials with bandgaps greater than 1.6 eV, it is proposed to use CdSe, with a bandgap of 1.72 eV, which is an optimum bandgap for a top cell of a tandem junction device when sharing the solar spectrum with an existing high-efficiency thin-film bottom cell. However CdSe likes to be an n-type semiconductor, which does not allow for its use as a top cell with the correct polarity on the high-efficiency p-type bottom cell for monolithically integrated (two-terminal) tandem devices. In this project an innovative approach to overcome this problem is proposed which involves using existing low-cost deposition techniques with added doping capability to fabricate p-type thin-films of CdSe. The retention of this conductivity type after high-temperature device processing will also be confirmed so as to enable high-efficiency devices as needed for application in the monolithic tandem device. Commercially, two of the most important near-term markets for high-efficiency flexible lightweight tandem-junction photovoltaics are space and high-altitude airships (HAA). In addition it is possible to leverage the monolithic tandem PV space/HAA product technology for the implementation of a low-cost monolithic tandem PV terrestrial product. The terrestrial product is anticipated to have a significant impact toward reducing the cost of alternative energy (solar electric).

这个小企业技术转让（STTR）第一阶段项目将开发一种宽带隙薄膜半导体，以实现单片串联或多结薄膜光电子器件中顶部电池的高效光吸收层。 由于相对较高的器件封装成本，串联结薄膜光伏器件可以提供比它们的单结对应物更高的每平方米瓦特数和更低的每瓦特成本。 为了克服当前对于带隙大于1.6eV的材料的低薄膜器件效率，提出使用具有1.72eV的带隙的CdSe，当与现有的高效薄膜底部电池共享太阳光谱时，这是串联结器件的顶部电池的最佳带隙。 然而，CdSe喜欢是n型半导体，这不允许其用作单片集成（双端子）串联器件的高效p型底部电池上的具有正确极性的顶部电池。 在这个项目中，提出了一种创新的方法来克服这个问题，它涉及到使用现有的低成本的沉积技术与添加掺杂能力，以制造p型薄膜的CdSe。还将确认高温器件处理后这种导电类型的保持，以便能够实现单片串联器件中应用所需的高效率器件。 在商业上，两个最重要的近期市场的高效率的灵活的轻型串联结光电子学是空间和高空飞艇（HAA）。 此外，还可以利用单片串联PV空间/HAA产品技术来实现低成本单片串联PV地面产品。预计该陆地产品将对降低替代能源（太阳能发电）的成本产生重大影响。