Printed Assembly of Micro/Nanomaterials with Silicon and Gallium Arsenide Based Compound Semiconduct

Printed Assembly of Micro/Nanomaterials with Silicon and Gallium Arsenide Based Compound Semiconductors for High Performance Photovoltaics and OptoelectronicsDr. Jongseung Yoon
Beckman Institute for Advanced Science and Technology
UIUCAbstract
In the first part of my talk, I will present our recent work that explores techniques to exploit silicon for unusual photovoltaic module designs. Silicon, in amorphous or various crystalline forms, is used in >90% of all installed photovoltaic (PV) capacity. The high natural abundance of silicon, with the excellent reliability and good efficiency of solar cells made with it, suggest its continued use, on massive scales, for the foreseeable future. As a result, although there is significant promise for organics, nanocrystals, nanowires and other new materials for photovoltaics, many opportunities continue to exist for research into unconventional means for using silicon in advanced PV systems. We developed new approaches to exploit printed arrays of ultrathin, monocrystalline Si solar microcells for unconventional photovoltaic modules. The resulting devices can offer many useful features, including high degrees of mechanical flexibility, user-definable levels of transparency, ultra-thin form factor micro-optic concentrator designs, together with the potential for high efficiency and low cost.In the second part of my presentation, I will discuss about releasable epitaxial multilayer assemblies of gallium arsenide (GaAs) based compound semiconductors for high performance photovoltaics and optoelectronics. Compound semiconductors such as GaAs provide unmatched performance in photovoltaic and optoelectronic devices. Current methods for growing and fabricating these materials are incompatible with the most important modes of use, particularly in photovoltaics, where large quantities of material must be distributed over large areas on low cost, amorphous foreign substrates. We developed new methods that address many of these challenges, through cost effective production of bulk quantities of high quality functional films of GaAs from thick, epitaxial assemblies formed in a single deposition sequence on a growth wafer. Specialized designs enabled separation, release and assembly of individual active layers in these stacks to create devices on substrates ranging from glass, to silicon and plastic, in quantities and over areas that exceed possibilities with conventional approaches.

Location: Hedco Pertroleum and Chemical Engineering Building (HED) - 116

Audiences: Everyone Is Invited

Contact: Petra Pearce Sapir