报告题目: Rare Earth-doped Oxide for Silicon Photonics

报 告 人: Prof. Yusui Nakamura（Computer Science and Electrical Engineering

Graduate School of Science and Technology, Kumamoto University）

时间: 2012年6月4日(星期一) 下午 14:00

地点: 中国科学院半导体研究所学术沙龙室

Abstract:Clockspeed of microprocessors has saturated around 4GHz because of serious problems in electrical wiring such as cross talks and clock skews. In addition, utilization of multi-core microprocessors producesbusy parallel processing. In order to make a breakthrough in the intra-chip communication, a silicon-based optical interconnection technology (silicon photonics) is highly required, but realisticlight sources are not developed yet because of an indirect bandgap property of Si. Recently, much attention has been attracted to erbium (Er)-doped silicon suboxide (SiOX) since its application to on-chip light source is promising in the 1.5μm band. Castagna et al have reported a high-efficiencyelectroluminescence from Er-doped SiOX (X~2) sandwiched by n-Si and p-Si.  However, there exist two critical problems: electrical breakdown of the SiOX layers and fairly high operation voltage (30~50V). To overcome the problems, we have proposed a combination of a lower oxygen composition (x~1.3) in Er-doped SiOX with a narrower optical bandgap of ~2eV and n-type SnO2 as a current injection layer. We have observed infrared electroluminescencefrom the device at low operation voltage less than 10V without the breakdown of the devices. Furthermore, we are studying Er-doped SnO2 to realize high-performance devices with lower operation voltage and higher stability using SnO2-based p-i-n structure.

Biography: Prof.Yusui Nakamura received the master’s degree from Tohoku University, Japan, in 1989 and Ph.D. degree from University of Tokyo, Japan, in 1999, both in electronics engineering. He joined the Quantum Wave Project (1989-1993) and the Quantum Transition Project (1994-1998) of Japan Science and Technology Corporation. Then, he worked in Max-Planck-Institute, Stuttgart, Germany, as a guest scientist (1999-2001). After that, he worked in the Femtosecond Technology Research Association, Japan. Since 1989, he studied on semiconductor nanostructures such as quantum wires, lateral superlattices, and quantum dots based on III-V materials. In 2004, he became a professor in the Faculty of Engineering, Kumamoto University, Japan. Then, he started a research on oxide semiconductors for new-type optical devices.