A concept for the assembly and alignment of arrayed microelectronic and micro-optical systems for optical multi-gigabit communication

In the first part of this contribution we present a concept for the fabrication, assembly and alignment of a multichannel micro optical-coupler and arrayed microelectronic devices placed on a PCB. This concept is based on a micro opticalcoupler that integrates several optical sub-systems in a monolithic substrate in order to simplify adjustment processes. The optical-coupler is fabricated by plastic replication of a metal master with the negative shape of the coupler. For the fabrication on the PCB, only one alignment step is necessary. By placing markers on the PCB it is possible to position the coupler over the VCSEL or photodiode array. The placement and connections between the electronic devices on the PCB are taken into account in the design of the coupler. The mechanical assemblies for populating PCBs with electronic devices have an accuracy of a few micrometers. Using these techniques an optimal position of the coupler relative to the VCSEL or photodiode array can be found. In the second part we examine with the help of simulations the effect of misalignment and tilt of the optical surfaces and possible differences between the optical fibers like decentering. Bitrates of 120 Gbps in a 12-channel system can be reached using this coupler with commercial electronic devices. Applications for this system are active optical cables and ultra wide-band board to board communication systems. A FPGA-board for the test of this concept is in the design phase and will be reported.