Linear InGaAsP edge-emitting LED´s for single-mode fiber communications

A 1.3-μm edge-emitting diode with a linear radiance and high coupled power into a fiber is described. The LED yields 60 μW of coupled power into a single-mode fiber at a driving current of 100 mA and an ambient temperature of 25°C. A V-groove structure with an optical absorption region separated from an active region is used. At active layer thicknesses below 0.14 μm, linear current-light output characteristics are obtained. The spectral modulation depth is 0% over the entire emission spectral width of 75 nm, and coherence length is 22.5 μm. LED characteristics are achieved in the range from -30 to 85°C at a driving current of 100 mA. The LEDs exhibit a cutoff frequency of 250 MHz. LED reliability is discussed using results of accelerated aging carried out at the ambient temperatures of 50, 125, and 200°C. The activation energy of degradation is determined to be 0.63 eV, and LED half-lives are estimated to be in excess of 10⁶ h