SBIR Phase I: Integration of Langmuir-Blodgett Quantum Dot Films Into Optoelectronic Device Heterostructures

这项小型企业创新研究第一阶段项目名为“将朗缪尔-布洛杰特量子点薄膜集成到光电器件异质结构中”，将推动将胶体半导体量子点（SQD）纳入无机半导体光电器件。纳米结构在IIInitride发光二极管在从紫色到蓝绿色的范围内的高效率操作中起着关键作用。Dot Technologies拥有新颖的知识产权，通过集成II-VI SQD层，将III族氮化物LED颜色扩展到深绿色。具有低壁插塞效率的电致发光器件已经由DMT和其他人证明。迄今为止用于存款SQD的滴铸和旋铸方法导致SQD的不均匀层，降低了通过异质结构的垂直电子输运的均匀性。在这个项目中，标准的朗缪尔-布洛杰特单层膜沉积技术将被用来存款单层的SQD。以这种方式，SQD有源层将与III族氮化物LED中的量子威尔斯具有相同的厚度。利用分子束磊晶技术将量子点封装成异质结构元件，并将制造出发光二极体，并进行测试，此计画的广泛影响是重大的。接近人眼响应峰值的深绿色光是“白色光”和彩色显示器的基本组成部分。通常，通过有损磷光体下转换产生深绿色。该项目将通过直接对SQD进行电抽，实现更高效率的深绿色发电。由此产生的设备将是高度适销对路，因此，这项工作将吸引更多的资金从非SBIR来源完成后。而且，对深绿色的直接电控制允许对主观色彩质量的更好控制，从而导致更高质量的照明和显示，并且还节省能量。SQD与传统半导体外延的集成本身是一种有市场的工艺，可能适用于其他类型的光电器件，如探测器或太阳能电池。迄今为止，DMT已经执行了另外四个SBIR项目，虽然还没有产品商业化，但已经取得了重大的技术进展，与这项工作有关的许多出版物证明了这一点

This Small Business Innovation Research Phase I project, entitled "Integration of Langmuir- Blodgett quantum dot films into optoelectronic device heterostructures", will drive incorporation of colloidal semiconductor quantum dots (SQD) into inorganic semiconductor optoelectronic devices. Nanostructure plays a critical role in high efficiency operation of IIInitride light emitting diodes over a range from violet to blue-green. Dot Metrics Technologies has novel intellectual property to extend III-nitride LED color to the deep green through integration of II-VI SQD layers. Electroluminescent devices with low wall plug efficiency have been demonstrated by DMT and others. Drop casting and spin casting methods used so far to deposit SQD result in non-uniform layers of SQDs, degrading uniformity of vertical electronic transport through the heterostructures. In this project, standard Langmuir-Blodgett monolayer film deposition techniques will be employed to deposit single layers of SQD. In this way, SQD active layers will be on the order of the same thickness as quantum wells in III-nitride LEDs. Molecular beam epitaxy (MBE) will be used to encapsulate SQD to form device heterostructures, and light emitting diodes will be fabricated and tested.The broader impact of this project is significant. Deep green light, near the human eye response peak, is an essential component of "white light" and multicolor displays. Typically, deep green is generated through lossy phosphor down-conversion. This project will result in higher efficiency generation of deep green through direct electrical pumping of SQD. Resulting devices will be highly marketable; thus, the work will attract further funding from non-SBIR sources upon completion. Also, direct electrical control of deep green allows better control of subjective color quality, resulting in higher quality lighting and displays, and also energy savings. Integration of SQD with traditional semiconductor epitaxy is itself a marketable process, potentially applicable to other types of optoelectronic devices such as detectors or solar cells. DMT has executed four other SBIR projects to date, and while no products have yet been commercialized, significant technical progress has been made as evidenced by the numerous publications associated with this work