Microcavity LEDs with an overall efficiency of 4% into a numerical aperture of 0.5

Summary form only given. Microcavity LEDs were optimised for optical interconnect requirements. Overall quantum efficiency of up to 4.3% into a numerical aperture of 0.5 and a FWHM beam divergence angle of 105 degrees at a drive current of 1 mA was achieved. Microcavity LEDs with one gold and one GaAs-AlAs DBR-mirror have been optimized for efficiency into a limited NA of 0.5. Simulations indicate that an efficiency of 8% can be achieved. Experimental devices give a best value of 3.7%.