Ren, Liming
Assistant Professor
Research Interests: Graphene nanodevices, modeling and simulation
Office Phone: 86-10-6275 2549
Email: renlm@ime.pku.edu.cn
Ren, Liming is an assistant professor in the Department of Microelectronics, School of Electronics Engineering and Computer Science, Peking University. She obtained her B.S. in 1994 and M.S. in 1999 from Shandong University, and Ph.D. from Institute of Microelectronics of Chinese Academy of Sciences in 2002 respectively. Her research interests include Graphene nanodevices and Monte Carlo simulation of Electron Beam Lithography (EBL).
Dr. Ren has finished two NSFC research projects. And she has taken part in more than ten research projects including NSFC, 973 programs, 863 project, etc. She has published more than 30 research papers and patents as the first author and co-authors. Her main research achievements are summarized as follows:
1) Graphene nanodevices: Graphene has emerged as a promising material for the next generation electronic devices benefiting from its exceptionally high crystal, electronic, optical and thermal qualities. She and her research team focused on the research of graphene nanodevices, including graphene material synthesis, transfer and characterization. They proposed a laser-induced PMMA residues removal technique. With proper exposure power and time, PMMA residues left on graphene surfaces can be substantially reduced without introducing any defects. By applying this technique to graphene devices, higher carrier mobility and lower contact resistance can be readily realized. Graphene-based field effect transistors with high properties have been fabricated. And bright visible light emission from electrically biased graphene has been successfully achieved.
2) Monte Carlo simulation of EBL: EBL is an important tool for nanostructure fabrication and nanodevice manufacturing . The proximity effect is the key factor influencing the resolution of EBL. And the random electron scattering phenomenon is the source of the proximity effect. Monte Carlo simulation is a proper method to simulate random events. She proposed a proper physical model and efficient Monte Carlo calculating model to simulate the electron scattering processes and the proximity effect in EBL. The influence of process conditions were simulated such as incident beam energy, resist thickness, substrate material, etc. The simulation efficiently helped to optimize process conditions and improve the exposure resolution of EBL.
