Hideki Tsunetsugu

Packaging technology for 40-Gb/s optical receiver module with an MU-connector interface

A compact 40-Gb/s optical receiver module with an MU-connector interface has been developed. Its packaging has three main technical features. (1) Coplanar waveguide (CPW) patterns of the waveguide photodiode (WG-PD) and of the preamplifier IC in the facing area of the flip-chip structure are optimized for impedance matching. (2) A film carrier is used to connect the preamplifier IC to an electrical coaxial connector for electrical signal output. (3) An MU-connector is used as the optical interface to reduce the module size. Optimum design enabled a module size of 14.0 mm wide, 40.4 mm long, and 9.65 mm high. Measurements showed a 3-dB down bandwidth of the optical/electrical response of at least 50 GHz and a clear open eye pattern for a 40-Gb/s nonreturn-to-zero (NRZ) signal input. This optical receiver module is suitable for large-capacity communication network systems.

A new packaging technology for high-speed photoreceivers using micro-solder bumps

A novel packaging technology for high-speed photoreceivers with a photodiode and a preamplifier is presented. This technology features micro-solder bumps, an impedance-matched film (IPF) carrier, and an optical fiber unit. Micro-solder bumps eliminate parasitic elements of the interconnection between the photodiode and the preamplifier. The IPF carrier drastically reduces the parasitic inductive elements of the interconnection between the preamplifier and the package, and provides an impedance-matched interconnection. The optical fiber unit with hemispherical-lensed fibers carries out high-efficiency optical coupling. The photoreceiver using these technologies achieves 10 Gbit/s optical heterodyne transmission.<<ETX>>