Abstract: Flip-chip truncated-pyramid-shaped bluemicro-light-emitting diodes (-LEDs), with different
inclinations of the mesa facets to the epitaxial layer plane, are studied by simulations, implementing
experimental information on temperature-dependent parameters and characteristics of large-size
devices. Strong non-monotonous dependence of light extraction efficiency (LEE) on the inclination
angle is revealed, affecting, remarkably, the overall emission efficiency. Without texturing of emitting
surfaces, LEE to air up to 54.4% is predicted for optimized shape of the -LED dice, which is
higher than that of conventional large-size LEDs. The major factors limiting the -LED performance
are identified, among which, the most critical are the optical losses originated from incomplete
light reflection from metallic electrodes and the high p-contact resistance caused by its small area.
Optimization of the p-electrode dimensions enables further improvement of high-current wall-plug
efficiency of the devices. The roles of surface recombination, device self-heating, current crowding,
and efficiency droop at high current densities, in limitation of the -LED efficiency, are assessed.
A novel approach implementing the characterization data of large-size LED as the input information
for simulations is tested successfully.
