A light emitting device including a transistor structure formed on a semiconductor substrate. The transistor structure having a source region, a drain region, a channel region between the source and drain regions, and a gate oxide on the channel region. The light emitting device including a plurality of nanocrystals embedded in the gate oxide, and a gate contact made of semitransparent or transparent material formed on the gate oxide. The nanocrystals are adapted to be first charged with first type charge carriers, and then provided second type charge carriers, such that the first and second type charge carriers form excitons used to emit light.