Size dependence of III-nitride microdisk light-emitting diode characteristics

Individual microdisk blue-light-emitting diodes (mu -LEDs) of varying diame ters from 5 to 20 mum have been fabricated from InGaN/GaN quantum wells. Si ze effects on the mu -LED characteristics, including I-V and L-I characteri stics, have been measured. The transient behavior of the mu -LEDs has also been studied. It was found that the turn-on time is on the order of our sys tem response (30 ps) and the turn-off time is on the order of 0.2 ns and sh ows a strong size dependence. The ability of two-dimensional array integrat ion with advantages of high speed, high resolution, low temperature sensiti vity, and applicability under versatile conditions make III-nitride mu -LED s a potential candidate for light sources in short-distance optical communi cations. (C) 2001 American Institute of Physics.