报告摘要：

由于二维材料特有的物理性质，其带隙可以从0变化到6eV,所以基于它的高性能多色探测器一直是人们追求的目标。首先通过对二维晶体金属半导体光电探测器光响应度随电极间距的变化规律系统研究，发现光响应度随着电极间距的增大而非线性衰减，并发展了理论模型来很好地解释了两种器件结构中光响应度与电极间距之间的依赖关系。通常金属电极光电探测器的速度为ms到几十毫秒量级，为了获得速度更高的光电探测器，我们利用单层石墨烯作为电极，发现可以将光探测器的速度提高到微秒量级。基于此我们研制了石墨烯作为电极的不同二维晶体p-n异质结光电探测器，实现演示了从紫外到近红外的高性能（高速度、高响应）光电探测器。

报告人简介：

王开友，中国科学院半导体所研究员/中国科学院大学岗位教授，博士生导师，国家杰出青年基金获得者，半导体超晶格国家重点实验室副主任。 2005年在英国诺丁汉大学天文物理学院获得哲学博士学位。2005年3月－5月在诺丁汉大学作研究助理， 2005年6月－2009年3月在日立剑桥研究实验室作Researcher。曾经两次在波兰科学院物理研究所做访问研究，并作为访问教授在丹麦玻尔研究所进行短期访问研究。2009年得到中国科学院"百人计划"的资助，加入半导体研究所超晶格国家重点实验室工作，迄今合作发表了90多篇科技论文，发表的文章被引用3000多次。 在27届国际半导体会议上被国际纯物理和应用物理组织（IUPAP）评为“青年优秀作者奖”； 且获得第二届“中国海外优秀自费留学生奖”；2012年获得“国家杰出青年基金”资助；2014年获得“中国侨界（创新人才）贡献奖”，并获得百人计划终期评估优秀。当前的研究兴趣主要是自旋电子学器件及低维纳米器件的物理特性研究。

报告摘要：

Black phosphorus (BP), as a fast-emerging two-dimensional (2D) material, stands out from other members in 2D family such as graphene and transition metal dichalcogenides (TMDs), and attracts substantial research interests attributed to its remarkably unique fundamental properties and versatile device applications. In this talk, I will summarize and discuss our recent work for interface engineered 2D materials phosphorene based field-effect-transistors (FETs) and photo-transistors, through the combination of in-situ FET device evaluation and photoelectron spectroscopy investigation. We will particularly emphasize on the electron and hole doping effect on the transport properties and optoelectronic response of phosphorene devices.

References

(1) “Surface Transfer Doping Induced Effective Modulation on Ambipolar Characteristics of Few-layer Black Phosphorus” Xiang D, Han C, Wu J, Zhong S, Liu YY, Lin JD, Zhang XA, Hu WP, Özyilmaz B, Castro Neto AH, Wee ATS, Chen Wei*, Nature Communication 6, 6485 (2015)

(2) “Epitaxial Growth of Single Layer Blue Phosphorene: A New Phase of Two-Dimensional Phosphorus" JL, Zhao ST, Han C, Wang ZZ, Zhong S, Sun S, Guo R, Zhou X, Gu CD, Yuan KD, Li ZY*, Chen Wei*, Nano Letter 16, 4903-4908 (2016)

(3) “Growth of quasi-free-standing single layer blue phosphorus on Tellurium monolayer functionalized Au(111)” Gu CD, Zhao ST, Zhang JL, Sun S, Yuan KD, Hu ZH, Han C, Ma ZR, Wang L, Huo FW, Huang W, Li ZY*, Chen Wei*, ACS NANO 11, 4943–4949 (2017)

(4) “Oxygen Induced Strong Mobility Modulation in Few-layer Black Phosphorus” Han C, Hu ZH, Carvalho A, Guo N, Zhang JL, Hu F, Xiang D, Wu J, Lei B, Wang L, Zhang C, Castro-Neto AH, Chen Wei*, 2D Materials 4 021007 (2017)

报告人简介：

Dr. CHEN Wei is currently an Associate Professor (2013 - ) in both Chemistry Department and Physics Department at National University of Singapore (NUS). He received his Bachelor’s degree in Chemistry from Nanjing University (China) in 2001, Ph.D. degree from Chemistry Department at NUS in 2004 under the supervision of Prof Loh Kian Ping and Prof Andrew T. S. Wee. His current research interests include Molecular-scale Interface Engineering for Molecular, Organic and 2D Materials-based Electronics, and Interface-Controlled Nanocatalysis for Energy and Environmental Research.