Intraband Processes and New Device Concepts in SemiconductorHomo and Hetero Junctions

9412248佩雷拉研究新的半导体器件的概念和带内过程导致主要在高性能红外成像和发射系统的潜在应用将被执行，其中独特的尺寸和成分控制能力提供了最近新兴的分子束外延生长技术将被修改，以发展特殊类型的新型结和多量子阱（MQW）格式。 在一个这样的格式，根据以前的NSF计划开发，在p-i-n同质结的界面功函数被控制在低值（对应于在VLWIR到FIR范围的光能）的注入或MBE生长的光发射区的重掺杂。 分析和实验的方法，旨在了解临界掺杂和尺寸参数的影响，以及偏置条件，对检测器和阵列的性能，建议MBE生长的多结结构，在更高的低温下的性能更高的潜力。 这项工作的主要意义是在建立一个技术基础的发展大面积，均匀的探测器阵列与多个特殊的能力，大大提高了NE T响应。 VLWIR MQW（A1，Ga，As）探测器的最新成功将被利用，通过将光电导和光伏（微带）结构的截止波长扩展到16 μ m以上，并检查瞬态操作模式作为提高响应和探测率的一种手段。 与康奈尔大学，NRC，UCLA和JPL的MBE专家合作，还将研究提高（Al，Ga）As势垒生长质量的可行性，作为降低较长波长暗电流的一种手段。 与Si同质结的情况一样，其固有的均匀性和低功率要求应使其能够在较长波长下超越HgCdTe探测器阵列。 多量子阱红外发射器结构的令人鼓舞的结果将提供一个很好的基础，进一步的建模工作和实验devices结合三能级和三重势垒功能作为一种手段，以提高粒子数反转的效率。 其他材料系统（例如InGaAs/InA 1As）也将被检查在MWIR范围内的高IR发射的潜力。 MQW发射器技术应导致稳定的，可集成的，大面积红外光源的波长从MWIR延伸到FIR，目前正在解决的小面积化学不稳定的碲镉汞和碲锡铅激光二极管的应用。 ***

9412248 Perera Research on novel semiconductor device concepts and intraband processes leading to potential applications primarily in high-performance infrared imaging and emitter systems will be performed in which the unique dimensional and compositional control capability offered by recently emerging MBE growth technology will be revised to evolve special types of novel junction and multi-quantum well (MQW) formats. In one such format, developed under a previous NSF program, the interfacial work function in p-i-n homojunctions is controlled at low values (corresponding to optical energies in the VLWIR to FIR range) by heavy doping of the implanted or MBE-grown photo-emitter region. Analytical and experimental approaches aimed at understanding the influence of critical doping and dimensional parameters, and of bias conditions, on detector and array performance be employed to suggest MBE-grown multi-junction structures with the potential for higher performance at more elevated cryogenic temperatures. The main significance of this work is in establishing a technology base for the evolution of large area, uniform detector arrays with a multi-special capability for greatly improved NE T responsivity. Recent successes with VLWIR MQW (A1, Ga, As) detectors will be exploited by extending the cutoff for both photoconductive and photovoltaic (miniband) structures to wavelengths beyond 16 um, and examining transient operation modes as a means of improving response and detectivity. Working in conjunction with MBE experts at Cornell, NRC, UCLA and JPL the feasibility of improved quality of (A1,Ga)As barrier growth, as a means of lowering dark current at longer wavelengths will also be studied. As is the case for Si homojunctions, the inherent uniformity, and their low power requirements, should enable them to out perform HgCdTe detector arrays at longer wavelengths. Encouraging results for MQW IR emitter structures will provide an excellent basis for further modeling efforts and experimental d evices incorporating three-level and triple-barrier features as a means to improve efficiency of population inversion. Other material systems (e.g. InGaAs/InA1As) will also be examined for the potential of high IR emission in the MWIR range. The MQW emitter technology should lead to stable, integratable, large area IR sources at wavelengths extending from MWIR to FIR, for applications currently being addressed by small-area chemically unstable HgCdTe and PbSnTe laser diodes. ***