Novel Packaging Structure Using VCSEL Array and Multi-Core Fiber for Co-Packaged Optics

A novel packaging structure for high-speed and high-density optical transceiver module sufficient for co-packaged optics is proposed. The optical transceiver module consists of a bottom-emitting 16-channel VCSEL array, a back-illuminated 16-channel PD array, a driver array, and TIA array. A multi-core fiber is used for each optical interface of optical transmitter and receiver, and a high-density LGA of 0.3 mm pitch is used for the electrical interface. In order to achieve high-speed and high-density CPO transceiver module, a core-less build-up multi-layer substrate manufactured by modified semi-additive process is used as an interposer. Low loss and low crosstalk characteristics up to several tens of GHz of fine pitch wirings enable to accommodate 25-Gbps x 16-channel optical transceiver in a 7.8 x 10 mm interposer.