Effects of thermal annealing on photoluminescence and structural properties of (ZnSe)2(CdSe)n short-period-superlattices multiple quantum wells
| Autor: | Yan-Kuin Su, R. C. Tu, S. T. Chou |
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| Rok vydání: | 1999 |
| Předmět: | |
| Zdroj: | Journal of Applied Physics. 85:2398-2401 |
| ISSN: | 1089-7550 0021-8979 |
| DOI: | 10.1063/1.369556 |
| Popis: | This work investigates how thermal annealing affects the optical and structural properties of (ZnSe)2(CdSe)n short-period-superlattices multiple quantum wells (SPS MQW) grown by molecular beam epitaxy using photoluminescence (PL) and high-resolution transmission electron microscopy (HRTEM) techniques. A characteristic that differentiates annealed SPS MQW from annealed conventional quantum wells is that much greater blueshifts can be observed in annealed SPS MQW as the annealing temperature rises above 400 °C. We attribute the larger blueshifts to thermally induced interdiffusion of Zn and Cd atoms between alternate ZnSe and CdSe layers. Furthermore, the PL emission in annealed (ZnSe)2(CdSe)n SPS MQW quenches at higher temperatures and yields a larger value for the activation energy than in as-grown SPS MQW. HRTEM images of samples annealed at 450 °C for 30 min clearly indicate that SPS structures remain in the quantum well regions of as-grown SPS MQW, but intermix and disappear in the well regions of anne... |
| Databáze: | OpenAIRE |
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