High reliability planar InGaAs avalanche photodiodes

The reliability of planar buried-structure InGaAs APDs (avalanche photodiodes) for long-wavelength optical transmission systems was investigated. High-temperature aging tests were performed at 150 degrees C, 175 degrees C, and 200 degrees C, and two distinctive failure distributions (early failure and wear-out failure) were observed. The early failure is predicted to be caused by microplasma at the periphery of the guard ring junction, and the wear-out failure is related to the InP/SiN/sub x/ interface degradation by hot hole injection. The activation energy of the wear-out failure is estimated to be 1.15 eV, and the extrapolated median life at 50 degrees C exceeds 10/sup 8/ h. In the second step of the life testing, burn-in screening at 200 degrees C was shown to be effective in removing early failure and achieving long-term stability. 750000 h of device operation has been achieved without any failure at test temperatures of 125 degrees C and 150 degrees C, which indicates high reliability of the APDs.<>