GaAs-based LED on Si substrate with GaAs islands active region by droplet-epitaxy

Using droplet-epitaxy, self-formed GaAs islands were successfully grown onGaAs/Si substrates by metalorganic chemical vapor deposition (MOCVD). The shapes and sizes of the islands were observed by atomic force microscope (AFM). In addition, a GaAs-based light emitting diode (LED) on Si with self-formed GaAs islands active region was fabricated for the first time. This LED was operated up to 27μW at 190 mA under room-temperature direct current (dc) conditions. Compared with a GaAs-based LED on Si with a GaAs quantum well active region, the reliability of this LED was much superior because of low dislocation density due to reduction of the active region by use of a GaAs island structure.