Alignment Control and Electrical Coupling of High-density Si-based Quantum Dots

2014 Fiscal Year Final Research Report

• Project/Area Number: 24246054
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Electronic materials/Electric materials
• Research Institution: Nagoya University
• Principal Investigator: SEIICHI Miyazaki 名古屋大学, 工学(系)研究科(研究院), 教授 (70190759)
• Co-Investigator(Kenkyū-buntansha): MAKIHARA Katsunori 名古屋大学, 大学院工学研究科, 准教授 (90553561)
• Co-Investigator(Renkei-kenkyūsha): MURAKAMI Hideki 広島大学, 大学院先端物質科学研究科, 助教 (70314739)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: Si系量子ドット / スーパーアトム

Outline of Final Research Achievements

Si-QDs with doped Ge core were self-assembled on thermally grown SiO2. PL spectra peaked at ~0.70 eV were observed, even at room temperature. The observed PL band suggested that radiative recombination of photo-generated carriers through quantized states of the Ge core is the dominant pathway for the emission from the dots, reflecting the type II energy band discontinuity between the Si clad and Ge core. We also found that, for P-delta doping to the Ge core, an ionized P donor is responsible for the efficient PL from the P-doped Ge core Si-QDs. In addition, multiple-stacked Si-QDs with ultrathin SiO2 interlayers were formed on ultrathin SiO2 layers. The kinetic energy of emitted electrons shows a peak at ~2.5 eV and less dependent on applied bias but a bias dependent tail toward the higher energy side. These results suggest that ballistical tunneling from the second and/or third topmost Si-QDs is maily responsible for observed electron emission.

Free Research Field

半導体工学