Packaging Technology for Ultra-Small Variable Optical Attenuator Multiplexer (V-AWG) With Multichip PLC Integration Structure Using Chip-Scale-Package PD Array

We have developed an ultra-small 16-channel variable optical attenuator (VOA) multiplexer (V-AWG) with excellent optical performance by using multichip planar lightwave circuit (PLC) integration technology. The insertion loss is 3.2 dB, and the polarization-dependent loss (PDL) at 25 dB attenuation is less than 0.3 dB. The module size is 90 mmtimes55 mmtimes14 mm. We describe our concept and developed techniques as regards to the design, fabrication, and packaging of the module, focusing particularly on a chip-scale-packaged monitor photodiode array (CSP-PD) that we developed as a key component of our technique