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

Abstract

Individual microdisk blue-light-emitting diodes (μ-LEDs) of varying diameters from 5 to 20 μm have been fabricated from InGaN/GaN quantum wells. Size effects on the μ-LED characteristics, including I–V and L–I characteristics, have been measured. The transient behavior of the μ-LEDs has also been studied. It was found that the turn-on time is on the order of our system response (30 ps) and the turn-off time is on the order of 0.2 ns and shows a strong size dependence. The ability of two-dimensional array integration with advantages of high speed, high resolution, low temperature sensitivity, and applicability under versatile conditions make III-nitride μ-LEDs a potential candidate for light sources in short-distance optical communications.

Fabrication of Two-Dimensional InGaN-Based Micro-LED Arrays

“…Compared to the conventional broad area LED, this kind of micro-device was found to have quite a high turn-on voltage ranging from 8.0 to 8.8 V. Although this range of operating voltages is comparable to that reported by Jin et al [2], who have used the same p-contact scheme as ours, we are not sure if the increase is due to the micro-size effect. In fact, we did not detect any differences from the turn-on voltages of the 8 mm and 12 mm micro-LEDs.…”

“…Recently, concepts in microcavity and microsize InGaN LED arrays have begun to be explored [1][2]. One of the potential applications of the microsize semiconductor display is in use as a synthetic cornea which can be implanted in a damaged eye, as has been anounced by a German research consortium [3].…”

Emission aperture size limited the guided mode extraction characteristics of GaN-based ultrathin-film photonic crystal micro-light-emitting diodes

“…These experimental results of absolute output power are better than the literature shows. [3][4][5] The output power enhancement of varying PhC emission aperture size is caused by the limited the finite extraction length of PhC. Recently, double-embedded PhCs (DPhCs) for extraction of the guided mode in LEDs have been shown to have an extraction length of the fundamental mode of approximately 21-39 lm.…”

“…Therefore, the microdisplays based on monochromatic GaN l-LED arrays that are driven in the passive and active mode have been developed. [1][2][3] The GaN l-LEDs have a number of advantages, such as brightness and high efficiency, over conventional size LEDs, which have been obtained by several groups 4,5 and are suitable for numerous potential applications, such as biophotonics and visible light communications. 6 A pico-projector using the l-LED array as the optical engine must be provided with directional far-field distribution, to enhance the light output efficiency and avoid crosstalk.…”

Mask-free photolithographic exposure using a matrix-addressable micropixellated AlInGaN ultraviolet light-emitting diode

“…We believe that this application demonstration opens up exciting directions for AlInGaN micropixellated emitters. Operation much deeper into the ultraviolet is possible using recent materials advances, 13 and the device may also be pulsed in subnanosecond duration 14 for nonlinear thresholding exposure effects. We note, furthermore, that self-aligned fabrication of integrated micro-optical elements is in principle possible using these methods.…”