Metal Halide Perovskites: Toward CMOS- Compatible Light Emitters

Abstract: Metal halide perovskite semiconductors are a proposed new generation of light emitting devices featuring high color quality, energy efficiency and low manufacturing cost. For example, perovskite LEDs with external quantum efficiencies above 20% have been realized. Despite rapid advances in performance of devices in the laboratory, better understanding of their fundamental properties is crucial for their optimization and commercial realization.

In this seminar, I will describe research in our group on fundamental properties of metal halide perovskite semiconductors, and on how that understanding can be deployed to immediately benefit device performance. First, I will discuss principles for perovskite semiconductors to be used as efficient light emitters, and will suggest a strategy to achieve stable bandgap tunability for wavelength-tunable LEDs and lasers. Next, I will present our work on improving the mechanical stability of perovskite semiconductors through molecular engineering for flexible applications, and on thermal management strategies for high-power applications. Third, I will describe our advances in using perovskite light emitters for high-speed applications and will discuss the path forward for developing CMOS-compatible light sources (e.g., thin film laser diodes). Finally, I will describe our findings on intrinsic chemical properties of metal halide perovskite semiconductors (e.g., redox and photoelectrochemical properties); this understanding is important for the development of stable perovskite devices for practical use.

Lianfeng Zhao is currently a Postdoctoral Research Associate at Princeton University. He received his Ph.D. from Princeton University in 2019, M.S. from Tsinghua University in 2014, and B.E. from Xidian University in 2012. His research focuses on optoelectronic thin-film materials, devices, and applications. His work has been recognized by a number of awards including the Princeton Wallace Memorial Honorific Fellowship and the Princeton School of Engineering and Applied Science Award for Excellence.