Simple assembly scheme of a corner-illuminated PD on a hybridly integrated planar lightwave circuit (PLC) platform

We report a planar integration scheme for a corner-illuminated photodiode (PD) on a planar lightwave circuit (PLC) platform for highly uniform optical coupling for receiver-PDs and monitor-PDs. We adjusted the marker on the PD to the waveguide on the PLC and the marker on the platform, and deviations from the center position are small, to within /spl plusmn/10 /spl mu/m. The corner-illuminated PD has large lateral tolerance of 65 /spl mu/m for the receiver-PD and 160 /spl mu/m for the monitor-PD. These result in high monitor current uniformity. High average coupling efficiency was obtained for the receiver-PD, with a loss of 0.7/spl plusmn/0.3 dB. As for the monitor-PD, uniform currents of 312/spl plusmn/45 /spl mu/A (/spl plusmn/0.7 dB in optical power) at -2 dBm optical power was obtained. The deviation of optical coupling between the LD and monitor-PD is estimated to be almost 0 dB, judging from deviation of the optical coupling between the LD and the PLC waveguide which is evaluated to be /spl plusmn/0.7 dB. We have confirmed that the corner-illuminated PD and its alignment method are promising for highly uniform characteristics with a surface mounting configuration.