This contribution presents near-field scanning optical microscope (NSOM) in illumination mode as effective tool for semiconductor device surface patterning. Though the effect of periodic structure application on the light emitting diode (LED) surface is well known, for the first time, the effect of irregular structure is investigated. The non-contact mode of the NSOM lithography was used to pattern two-dimensional irregular structure on the emitting surface of GaAs/AlGaAs-based LED. The structure was patterned in the upper confinement AlGaAs layer and the enhancement of radiation 1.2-1.5 times from the patterned air holes in comparison with the surrounding surface was proven, which is similar to the enhancement of light extraction efficiency published for periodic structure application. (C) 2012 Elsevier B. V. All rights reserved.