Optimization of Packaging for PIN Photodiode Modules for 100Gbit/s Ethernet Applications

In this paper the packaging of optical components is investigated employing a conductor backed coplanar waveguide (CBCPW). The study is performed using 3D electromagnetic (EM) simulations in a broadband range up to 110 GHz. Higher-order resonances are observed in both measurement and simulation results. Based on the verified EM simulation setup, the origin of resonances is identified and remedies are suggested in the paper. Several optimization schemes for achieving good transmission characteristics for the planar structure as well as for the coax-CPW transition are proposed such as properly coating side metallization on the CPW, substrate spacing to the metal housing, and developing metal posts in the substrate of the CPW.