Light emitting diodes (LEDs) have been fabricated, with an overcut sidehole (OS) structure in the LED mesa. The OSs with 57 angle has been perfectly formed by wet-etching with a simple and controllable process. Lateral light that is guided along the GaN epilayer in the OS-LEDs is found to be significantly redirected by the OS structure as a reflector, and can be extracted from the LEDs. The performance of the OS-LEDs is compared with that of conventional LEDs and the light output power of the OS-LED is enhanced by 49% over that obtained from conventional LEDs. It is noticed that wet etching does not degrade the electrical properties of the devices. (C) 2009 Elsevier Ltd. All rights reserved.