Taking cues from the evolution of the electronic IC technologies, the future development of opto-electronic integrated circuit's (OEICs) needs CAD models and tools, in addition to developing better and more devices. It is our aim to investigate the whole component integration chain from the optoelectronic device to the micro-opto-mechanical components constituting the interconnect module. We use both a sensitivity analysis to misalignment errors and Monte Carlo simulations. We furthermore give special attention to the optical tolerancing and the opto-mechanical integration of the components. We will address more specifically in this paper the following components: 1) out-of-plane couplers for optical wave-guides embedded in PCB, 2) peripheral fiber ribbons and two dimensional single- and multimode fiber connectors for high-speed parallel optical connections, and 3) intra-MCM level optical interconnections via free-space optical modules. In our labs at the Vrije Universiteit Brussel we are therefore focusing on the continuous development of a rapid prototyping technology for micro-optical interconnect modules, which we call Deep Proton Writing (DPW).The special feature of this prototyping technology is that it is compatible with commercial low-cost mass replication techniques such as micro injection moulding and hot embossing.
One of the grand challenges in solving the interconnection bottlenecks at the Printed Circuit Board (PCB) and Multi-Chip-Module (MCM) level, is to adequately replace the PCB and intra-MCM galvanic interconnects with high-performance, low-cost, compact and reliable micro-photonic alternatives. We determined that controlling the adhesive bonding of the opto-mechanical structures and the opto-electronic device to minimize tilt errors will be of utmost importance in a real-world assembly process. We have been able to integrate our module in a demonstrator with a large opto-electronic device containing Vertical Surface Emitting Lasers and Resonant Cavity Photodetectors. In addition the technique can create microlenses with various lens diameters and sag on the top surface of the substrate. DPW is able to define sidewall surfaces with optical quality in 500 μm tick Polymethyl Metacrylate (PMMA) samples. We have used the opto-mechanical simulation framework to predict the process yield of our in-house micro-optomechanical fabrication technology, which we call Deep Proton Writing (DPW). We will detail an approach to optimize the fabrication and assembly yield. Scaling these variances allows us to asses the effect of a technology accuracy enhancement on the number of fabricated systems that comply with the performance specifications. We subsequently simulate the random combination of errors on all parameters in a Monte Carlo simulation in which the variances of the random errors are set to to a fraction of the sensitivity limits. Sensitivity limits are set depending on the minimum performance specifications of the module. Our design methodology starts with an analysis of the sensitivity of each parameter on the optical efficiency and cross-talk of the module. The model allows us to examine the optical performance of the interconnect system under various fabrication and assembly errors using a Monte Carlo simulation. To this aim we have built an opto-mechanical model of the complete interconnect. We report on the opto-mechanical design and performances of an intra-multi-chip-module free-space optical interconnect, integrating microlenses and a deflection prism above a dense opto-electronic chip, under various fabrication and assembly errors.
0 kommentar(er)
