Realization of highly efficient and high-speed resonant cavity LED for coupling to plastic optical fibers

Planar Resonant Cavity LEDs (RCLEDs) are suitable light sources for parallel interchip interconnect links, due to their high efficiency, zero-threshold, low voltage, high reliability and high speed characteristics. The through- substrate emitting RCLEDs, optimized for Polymer Optical Fiber (POF) coupling, consist of an InGaAs quantum sandwiched between a metal mirror and a distributed Bragg reflector. The RCLEDs are arranged in 8 X 8 arrays with 250 um pitch. The arrays have been mounted onto glass carriers, and the coupling efficiency into POF, the far- field pattern and the modulation characteristics are measured. The overall quantum efficiency of the devices with 50 um diameter was found to be 13.4%, the QE into POF was 3.7%. The large-signal transient behavior of the devices has been investigated. Using a high-speed pulse source, nanosecond rise and fall times have been measured. Wide open eye diagrams at 1 Gbit/s were obtained using voltage pulse drivers. These data were compared to theoretical results based on a non-linear rate equations model.