碩士 長庚大學 電子工程研究所 92 The most popular epitaxial technique of creating quantum-dot heterostructure nowadays is utilizing the strain stored in the interface of two lattice-mismatched materials to form self-assembled quantum dots. Thus it is thought that the strain will be an important issue in the electronic and physical characteristics of quantum dot heterostructure. In this article, five multi-layer quantum dot samples grown on substrates with different vicinal angle were chosen to investigate their strain properties. To examine the strain property of these samples, two kinds of experiment techniques, temperature- and polarization-dependent photoluminescence, were performed. And the results will be discussed here to deduce geometric and strain properties of these samples.