SBIR Phase I: Advanced Nanomaterials Based on Quantum Dots with Built-in Charge for Sensing and Photovoltaics

这个小企业创新研究第一阶段项目将重点开发具有长光载流子寿命、低复合损耗和增强红外（IR）辐射耦合的新型光电纳米材料。实现这一目标的创新是使用内置电荷的量子点（QD）来创建指定的三维电位分布，其中红外吸收区域（QD， QD行和QD簇）通过电位屏障与导电通道分开。通过对点间空间的选择性掺杂来实现点的充电。由此产生的长光电子寿命将提高基于该创新的传感器的光导增益和响应性。这种结构还可以降低产生复合噪声，提高光电探测器的灵敏度。低复合损耗和增强对红外辐射的耦合将提高量子点太阳能电池的光电效率。第一阶段的研究包括纳米级设计，生长和加工技术的发展，以及测试结构和原型设备的综合分析。通过提供所需的基础和技术基础，该计划将开发具有许多光电应用的先进纳米材料。该项目更广泛的影响/商业潜力将是开发新型光电纳米材料，这将导致红外传感和光伏技术的潜在突破。通过适当的修改，该技术几乎适用于所有以任何方法制造的量子点材料和结构。光电纳米材料结合了强耦合辐射和光载流子寿命长和可控的特点，对下一代红外传感器的发展至关重要。在室温下工作的敏感探测器将大大增加红外技术的商业市场，红外技术的应用包括工业和环境监测、化学传感、医疗诊断和爆炸物探测。这些结构的高可扩展性为成像应用提供了广泛的机会。当集成到p-i-n结中用于太阳能收集时，这些结构将提供额外的约20%的转换效率提高（允许45-50%的总效率没有聚光器）。在第一期项目中，我们将证明以这种方式收集和转换红外辐射可使总转换效率至少增加7%。潜在的高效率和相对较低的成本（与高效的多结电池相比）使该技术在各种光伏应用中具有商业可行性。

This Small Business Innovation Research Phase I project will focus on development of novel optoelectronic nanomaterials with long photocarrier lifetimes, low recombination losses, and enhanced coupling to infrared (IR) radiation. The innovation which will enable this is the employment of quantum dots (QDs) with built-in charge to create specified three-dimensional potential profiles, where the areas of IR absorption (QDs, QD rows, and QD clusters) are separated from the conducting channels by potential barriers. The charging of dots is realized by selective doping of the interdot space. The resulting long photoelectron lifetime will increase the photoconductive gain and responsivity of sensors based on this innovation. This structure will also decrease the generation-recombination noise and improve the sensitivity of photodetectors. Low recombination losses and enhanced coupling to IR radiation will improve the photovoltaic efficiency of quantum dot solar cells. The Phase I research includes nanoscale design, development of growth and processing technologies, and comprehensive analyses of the test structures and prototype devices. By providing the needed fundamental and technological basis, this program will develop advanced nanomaterials with a number of optoelectronic applications.The broader impact/commercial potential of this project will be development of novel optoelectronic nanomaterials, which will lead to potential breakthroughs in IR sensing and photovoltaics. With appropriate modifications, the technology is applicable to practically all QD materials and structures fabricated by any method. Optoelectronic nanomaterials that combine strong coupling to radiation with long and manageable photocarrier lifetime are crucial for the development of next generation IR sensors. Sensitive detectors operating at room temperature will significantly increase the commercial market of IR technologies, which have applications including industrial and environmental monitoring, chemical sensing, medical diagnostics, and detection of explosives. The high scalability of these structures provides a wide opportunity for imaging applications. When integrated into in p-i-n junctions for solar energy harvesting, these structures will provide an additional ~20% improvement in the conversion efficiency (allowing 45-50% total efficiency without concentrators). In the Phase I project, we will demonstrate that harvesting and conversion of IR radiation in this way adds at least an additional 7% to the total conversion efficiency. The potential high efficiency and relatively low cost (as compared with efficient multi-junction cells) make this technology commercially viable for various photovoltaic applications.