Optoelectronic components such as laser diodes and light-emitting diodes are vulnerable to electrostatic discharge
(ESD) and electrical overstress (EOS). In this paper, we extensively study the size effect on ESD performance of
buried heterostructure (BH) distributed feedback (DFB) InGaAsP/InP lasers. We show that the ESD threshold and degradation
behavior of BH lasers are correlated with the cavity length and contact width. The ESD threshold increases linearly
with increasing cavity length and contact width. For the ESD degradation behavior, the occurrence frequency of hard degradation,
a behavior characterized with a sudden jump in threshold current during the ESD voltage ramp, decreases with
increasing cavity length. We also show that the dielectric layer is influential in ESD performance. The physical mechanisms
of the ESD behavior will also be discussed.