摘要: | 研究期間:10108~10207;In this three-year project, we aim to explore cutting-edge fabrication technologies for realizing novel and advanced quantum dot (QD) optoelectronic devices, such as single-electron transistors (SETs), QD photosensitive transistors (PTs), and rainbow solar cells. In addition, we will engage in a deep understanding of QD mesoscopic electricallyand optically driven quantum transports as well as quantum optical effects, which are fundamental but very crucial for QD nano-optoelectronics from functional prototypes into the realm of real application. Motivation to employ QDs in advanced optoelectronic devices is strong in light of its distinctive features of quantum confinement and Coulomb blockade effects. Accordingly we intend to make progresses in the innovation of device functionalities, the improvement of device performance, and even the breakthrough of traditional fabrication bottlenecks and classical physical limitation if possible. The research scheme of this three-year project is proposed to be as follows. In the 1st year, we will demonstrate high performance Ge QD SETs by integrating Ge QDs precise placement and self-aligned electrode technologies. A high performance SET would provide a superior test platform for characterizing QD internal structure properties (crystallinity, morphology, strain, and composition), QD electronic structure (charging energy, energy level separation, coupling strength, and oscillator strength), inter-particles Coulomb interactions, as well as steady-state and transient quantum transports wherein. The capability of QD placement and the knowledge of QD basic internal and electronic structures would lay nature cornerstones for the 2nd and 3rd year research themes “QD phototransistors” and “QD solar cells”. The developed high density QD growth technology and the understanding of exxitons Coulomb interactions in the 2nd year will be a natural extension to realm of QD solar cells in the 3rd year. The proposed research themes in each year are: 1st year: Ge QD single electron transistors (1) Demonstrating high performance Ge QD SETs (2) Investigation of steady-state tunneling spectroscopy. (3) Investigation of photoexcited tunneling spectroscopy. (4) Investigation of transient quantum transport and carrier lifetime. 2nd year: Ge QD phototransistors (1) Developing high density Ge QD stacks growth technology (2) Design of QD interface engineering. (3) Demonstratinghigh performance QD phototransistors (4) Investigation of quantum optical effects in QD phototransistors 3rd year: QD solar cells (1) Developing SiGe QD 3D arrays with grading composition and dot size (2) Investigation of carrier generation/recombination and multi-exciton generation (3) Investigation of intermediate band formation between QDs (4) Demonstrating high performance QD solar cells in PIN or MOS structure There are scientific and technologic significances involved in this proposed project. The research of SETs, phototransistors, and solar cells are closely related to quantum optoelectronics, which is a frontier research field. The implementation of SETs, phototransistors, and solar cells demands smart device design, precise QD growth and placement, and process integration, which will become the key technologies for the industry of nano-optoelectronics. |