Printed Assemblies of Inorganic Light-Emitting Diodes for Deformable and Semitransparent Displays

TLDR

The authors use specialized epitaxial semiconductor layers to produce ultrathin LEDs that can be printed onto glass, plastic, or rubber substrates in arbitrary layouts over large areas, and then interconnected with conventional planar processing. They demonstrate that microscale inorganic LEDs can be fabricated and assembled into flat or wavy displays and lighting elements ranging from micrometers to millimeters, providing novel mechanical and optical properties.

Abstract

We have developed methods for creating microscale inorganic light-emitting diodes (LEDs) and for assembling and interconnecting them into unusual display and lighting systems. The LEDs use specialized epitaxial semiconductor layers that allow delineation and release of large collections of ultrathin devices. Diverse shapes are possible, with dimensions from micrometers to millimeters, in either flat or "wavy" configurations. Printing-based assembly methods can deposit these devices on substrates of glass, plastic, or rubber, in arbitrary spatial layouts and over areas that can be much larger than those of the growth wafer. The thin geometries of these LEDs enable them to be interconnected by conventional planar processing techniques. Displays, lighting elements, and related systems formed in this manner can offer interesting mechanical and optical properties.