Ultra high performance planar InGaAsPIN photodiodes for high speed optical fiber communication

This paper reports a front-illuminated planar InGaAs PIN photodiode with very low dark current, very low capacitance and very high responsivity on S-doped InP substrate. The presented device which has a thick absorption layer of 2.92 mu m and a photosensitive area 73 mu m in diameter exhibited the high performance of a very low capacitance of 0.47 pF, a very low dark current of 0.041 nA, a very high responsivity of 0.99 A/W (79% quantum efficiency) at gamma=1.55 mu m, the 3 dB bandwidths of 6.89 GHz (-5V), 7.48 GHz (-12V) for bare chips and 4.48 GHz (-5V), 5.02 GHz (-12V) for the devices packaged in TO can, respectively. Furthermore, the developed PIN photodiodes possess high breakdown voltage of less than -25V. (c) 2006 Elsevier B.V. All rights reserved.