Optical and Far Infrared Studies of Semiconductor Heterostructures

这是对半导体异质结构研究的一个更新的建议。分子束外延（MBE）将用于制造三种新的半导体系统：II-VI自组装量子点（QDs）；稀释磁性III-V半导体；II- VI型半导体微腔。自组装量子点项目将重点研究在ZnSe上生长的CdSe量子点。III-V型磁性体系的形成将通过MBE生长III-V型化合物和锰硫族化合物（如MnTe）的固溶体来尝试。最后，II-VI微腔的制备将重点放在ZnSe/ZnCdSe量子阱结构的分布式Bragg反射器的MBE制备上。上述系统将通过光致发光光谱、光吸收和磁光方法进行研究。这三个项目都涉及与半导体异质结构光电应用相关的基本问题。这是对半导体异质结构研究的一个更新建议。薄膜系统由不同半导体（异质结构）的交替层组成，在技术上重要的器件中起着关键作用，如发光二极管、半导体激光器和传感器。分子束外延是一种形成这种多层膜的方法，具有前所未有的原子尺度的完美性。目前的项目将把这种方法应用到三个新的领域：在三个方向上形成100个原子规模的半导体结构（“量子点”）；技术上重要的磁性半导体的形成，其特性可以随着磁场的变化而变化；“微腔”的制造对蓝光发射器的工作具有直接的重要性。这些系统的光学研究有望为新的光电应用铺平道路。* * *

9705064 Dobrowolska This is a renewal proposal to study semiconductor heterostructures. Molecular beam epitaxy (MBE) will be used to fabricate three new semiconductor systems: II-VI self-assembled quantum dots (QDs); diluted magnetic III-V semiconductors; and II- VI semiconductor microcavities. The self-assembled QD project will focus on investigation of CdSe QDs grown on ZnSe. Formation of III-V magnetic systems will be attempted by MBE growth of solid solutions of III-V compounds and Mn chalcogenides (e.g., MnTe). Finally, fabrication of II-VI microcavities will focus on MBE fabrication of distributed Bragg reflectors for ZnSe/ZnCdSe quantum well structures. The above systems will be investigated by photoluminescence spectroscopy, optical absorption, and magneto-optical methods. All three projects address fundamental issues relevant to optoelectronic applications of semiconductor heterostructures. %%% This is a renewal proposal to study semiconductor heterostructures. Thin film systems consisting of alternating layers of dissimilar semiconductors ("heterostructures") play a critical role in technologically important devices, such as light emitting diodes, semiconductor lasers, and sensors. Molecular beam epitaxy is a method of forming such multilayers with unprecedented atomic-scale perfection. The present project will apply this method to three new frontiers: the formation of semiconductor structures on the scale of 100 atoms in all three directions ("quantum dots"); the formation of technologically important magnetic semiconductors whose properties can be varied by magnetic field; and fabrication of "microcavities" of immediate importance to the operation of blue light emitters. Optical studies of these systems are expected to pave the way toward new optoelectronic applications. ***