3-dB Bandwidth Enhancement via Mesa-Diameter Reduction in a InGaAs/InP Modified Uni-Travelling Carrier Photodiode Structure

Lens-integrated InGaAs/InP photodiodes whose mesa diameters range from 7 to 25 micrometers were fabricated by applying a wet-etch photodiode-mesa forming process to a 2-inch semi-insulating InP wafer with a modified uni-travelling carrier epitaxial structure. It was experimentally confirmed that the mesa diameters less than 14 micrometers produce a saturated maximum 3-dB bandwidth of about 45 GHz.