Planar InP-InGaAs single-growth avalanche photodiodes with no guard rings

A novel single-growth planar avalanche photodiode (APD) structure without guard rings is described. InP-InGaAs separate absorption, charge sheet, grading, and multiplication (SAGCM) APD's have been fabricated using the new edge breakdown suppression method. A very low, dark current of 0.6 nA at 0.98 of the breakdown voltage (BV) was measured for a 30-μm-diameter device. The maximum -3-dB electrical bandwidth was 6.1 GHz, and in the absence of obvious inductive peaking.