应中国科学院上海微系统所“千人计划”王庶民研究员邀请，瑞典查尔姆斯理工大学赵欢博士将于8月31日来微系统所访问，并作学术报告，具体信息如下： 

　　报告题目：Molecular beam epitaxy of catalyst-free InAs nanowires on Silicon 

　　报告人：赵欢 副教授 

　　报告时间：8月31日（（星期一）13:30 

　　报告地点：8号楼6楼会议室 

　　报告摘要：Semiconductor nanowires (NWs) represent a unique system for exploring phenomena at the nanoscale and are also expected to play a critical role in future electronic and optoelectronic devices. For some functional NW devices it is essential to have control over position, size and directionality of the NWs for homogenous and predictive performance. Moreover, the growth of device-quality nanowires with high purity should abstain from conventional nucleation schemes that employ foreign catalysts such as gold. Recent progress in selective-area epitaxy (SAE) technique has allowed position controlled catalyst-free growth of NWs, where semiconductor substrates are masked by dielectrics with nanoholes pattern. This is a kind of template method, which involves a combination of bottom up (epitaxial growth) and top down (lithography) approaches. However, current approaches for the nano-patterning are mainly based on electron beam lithography (e-beam), which is expensive and not suitable for large scale productions. 

　　In this work, two approaches are used to grow catalyst-free InAs NWs on Si by molecular beam epitaxy (MBE). In the first approach, a fully bottom-up strategy for selective-area epitaxy of nanowires using templates by bottom-up colloidal lithography is presented. The colloidal lithography presents a short-range ordered nanoholes patterned template with controlled pattern, size and nanoholes spacing, thereby opening perspectives for mass production of high-performance nanowire-based devices.  In the second approach, epitaxy of non-ordered catalyst-free InAs NWs was demonstrated on substrates without lithography patterning. This is realized by generating pinholes in the SiO₂ layer with wet etching. High density and high aspect ratio InAs NWs were obtained using this method. 

　　报告人简介：

      赵欢，女，1982年出生于河南。2002 年7月于郑州大学物理系获得学士学位。2008 年12月获中国科学院半导体所工学博士学位，2009年4月获瑞典查尔姆斯理工大学工学博士学位。2009-2011年于瑞典查尔姆斯理工大学太赫兹与微波实验室做博士后, 2011-2015年任助理教授, 2015年被提升为副教授。于2012 年获得瑞典研究委员会（VR）青年基金,　瑞典国家航天局科研基金，2013年获Hasselblad女科学家发展基金。已在国际权威刊物和会议发表论文70余篇。同时已成为IEEE和AIP等多个出版社的多种刊物的审稿人。自2011年以来任欧盟EU-FP7-FET-open，EU-FP7-ICT-2013-XTrack项目申请评委(已参评七十多个项目申请)。 

　　早期从事研究包括：1分子束外延生长GaInNAsSb量子阱,In(Ga)As量子点及其光学性质；2半导体边发射激光器,垂直腔面发射激光器,半导体光探测器及其在光纤通讯方面的应用。 

　　目前研究方向为：1分子束外延高迁移率半导体电子材料,异变材料；2分子束外延新型纳米材料; 3新型太赫兹电子器件研究。 

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