SEMINAR LMGP - 19.05.2020 - Pierre GAFFURI
Eco-efficient oxide materials for white LED
Pierre GAFFURI
PhD student / LMGP & Institut Néel – CDP EcoSESA
Abstract
Phosphor-converted white-emitting diodes (wLED dominate the lighting market due to their outstanding efficiency, long lifetime and ease of integration into electrical networks. They combine the excellent optoelectronic properties of InGaN-based blue LED and YAG:Ce phosphors. After an in-depth description of the criticality of such materials, I will present new substitution path toward eco-efficient lighting: ZnO NWs grown by low cost and low temperature chemical bath deposition (CBD), acting as the n-type semiconductor in the LED, as well as metal-aluminoborate micropowders synthesized by the low cost polymeric precursor (PP) method, acting as rare-earth-free phosphor. The implementation of ZnO NWs into LED requires i) to understand their doping mechanisms by CBD, ii) to identify the resulting defects that define their electrical and optical properties, and iii) to master their growth on p-type semiconductor (GaN) and their device integration. On the other hand, the development of rare-earth-free aluminoborate phosphors requires iv) to understand the role of the chemical composition and thermal treatments on their structure, v) to assess the resulting photoluminescence, vi) and to identify the nature of the emitters. These points will be thoroughly covered, providing key elements on the integration of eco-efficient oxide materials into wLEDs. Finally, economically wise, consumers’ willingness to pay for such eco-efficient devices will be discussed.Date infos
at 2 p.m. - by visioconference