Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7999103 | Journal of Alloys and Compounds | 2015 | 23 Pages |
Abstract
This study discovered the origin of deep level emission in zinc-blende ZnCdSe thin films grown by molecular beam epitaxy, in which a localization behavior was noticed. Pronounced deep level emission observed in films grown under a VI/II ratio of 1.74 (Se-accumulated regime) could be suppressed by a lower VI/II ratio of 1.04 (intermediate regime) and 0.74 (metal-rich regime). Hence the localized states could be correlated to excess selenium accumulated at the growth surface. The localized states also influence the carrier relaxation process of self-assembled ZnTe quantum dots embedded in a ZnCdSe matrix. Once quantum dots surmount the wetting layer, localized electrons in the capping layer dominate the type-II transition and exhibit size-independent lifetimes.
Keywords
Related Topics
Physical Sciences and Engineering
Materials Science
Metals and Alloys
Authors
Ling Lee, Yue-Ru Dai, Chu-Shou Yang, Wen-Chung Fan, Wu-Ching Chou,