title: GaAs photovoltaics and optoelectronics using releasable multilayer epitaxial assemblies.
abstract: Compound semiconductors like gallium arsenide (GaAs) provide advantages over silicon for many applications, owing to their direct bandgaps and high electron mobilities. Examples range from efficient photovoltaic devices to radio-frequency electronics and most forms of optoelectronics. However, growing large, high quality wafers of these materials, and intimately integrating them on silicon or amorphous substrates (such as glass or plastic) is expensive, which restricts their use. Here we describe materials and fabrication concepts that address many of these challenges, through the use of films of GaAs or AlGaAs grown in thick, multilayer epitaxial assemblies, then separated from each other and distributed on foreign substrates by printing. This method yields large quantities of high quality semiconductor material capable of device integration in large area formats, in a manner that also allows the wafer to be reused for additional growths. We demonstrate some capabilities of this approach with three different applications: GaAs-based metal semiconductor field effect transistors and logic gates on plates of glass, near-infrared imaging devices on wafers of silicon, and photovoltaic modules on sheets of plastic. These results illustrate the implementation of compound semiconductors such as GaAs in applications whose cost structures, formats, area coverages or modes of use are incompatible with conventional growth or integration strategies.
authors.affiliation: Department of Materials Science and Engineering, Beckman Institute for Advanced Science and Technology, and Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
authors.forename: Jongseung
authors.initials: J
authors.lastname: Yoon
authors.forename: Sungjin
authors.initials: S
authors.lastname: Jo
authors.forename: Ik Su
authors.initials: IS
authors.lastname: Chun
authors.forename: Inhwa
authors.initials: I
authors.lastname: Jung
authors.forename: Hoon-Sik
authors.initials: HS
authors.lastname: Kim
authors.forename: Matthew
authors.initials: M
authors.lastname: Meitl
authors.forename: Etienne
authors.initials: E
authors.lastname: Menard
authors.forename: Xiuling
authors.initials: X
authors.lastname: Li
authors.forename: James J
authors.initials: JJ
authors.lastname: Coleman
authors.forename: Ungyu
authors.initials: U
authors.lastname: Paik
authors.forename: John A
authors.initials: JA
authors.lastname: Rogers