The mesa width of green light-emitting diodes (LEDs) was scaled from the micrometer to the nanometer range. The devices were patterned by electron beam lithography and dry etching and contained up to 100 parallel nano-stripe LEDs connected to one common contact area. The mesa width was varied over 1 µm, 200 nm, and 50 nm. The LEDs were characterized electrically and optically, and the peak emission wavelength was found to depend on the lateral structure size. Light emission from the patterned region was found to be 4 times brighter than from the un-patterned regions. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)