Optoelectronic Characterization and Device Considerations of Next-generation Semiconductors

Title: Optoelectronic Characterization and Device Considerations of Next-generation Semiconductors.  

Speaker:  Professor Qianqian Lin, School of Physics and Technology, Wuhan University, China

Abstract: Along with the remarkable progress in the field of organic, quantum dot based- and recently emerged perovskite optoelectronics, solution-processed semiconductors have shown unprecedented successes. However, the characterization of these novel semiconductors is very challenging due to the highly disordered structure, low conductivity and relatively short charge carrier lifetimes. In this talk, I will present the optoelectronic characterization of these novel materials systems, mainly via time-resolved photoluminescence (TRPL), time-resolved microwave conductivity (TRMC) and optical-pump terahertz-probe (OPTP) spectroscopy. I will also introduce deep-level transient spectroscopy (DLTS), transient photovoltage (TPV) and Charge extraction by linearly increasing voltage (CELIV) to evaluate the fundamental properties of trap states, charge recombination and extraction based on operational devices. I will start with the basic principles and the set-up of these techniques. Then, the obtained optoelectronic properties, including real and imaginary conductivity, mobility, recombination rates, trap density and carrier lifetime, will be introduced for design and optimization of various devices. At the end, I will discuss the key challenges facing optoelectronic characterization and will also point out the opportunities, which are promising to explore and may require more research activities.

Bio: Qianqian Lin is currently a professor of materials physics at the School of Physics and Technology, Wuhan University, China. He received his PhD degree (Dean’s Award) from The University of Queensland in 2016 under the support of International Postgraduate Research Scholarship (IPRS, Australia). In 2016, he also received Materials Research Society (MRS) Graduate Student Gold Award (globally only selected 7 Awardees). After a postdoc in the Clarendon Laboratory at University of Oxford (Marie Skłodowska-Curie ITN fellowship, EU), he joined Wuhan University as a principal investigator in 2017. He was supported by the Chinese outstanding young researcher fellowship (>1 million AUD, China) in 2018. His research focuses on functional materials and optoelectronic devices. He has published more than 110 papers in high impact journals, such as Nat. Photonics(2), Nat. Energy (5), Nat. Commun.(3), Appl. Phys. Rev.(3), Matter,  Adv. Mater.(3), Adv. Energy Mater.(2), ACS Energy Lett. and Adv. Funct. Mater.(5), with a citation of >7200 and h-index of 31. He has also served as a guest editor of JPhys Photonics and reviewer of Nat. Electron., Nat. Commun., Joule, Adv. Mater., Nano Lett. etc.