High-precision 2-D SM fiber connectors fabricated through deep proton writing

High-precision two-dimensional (2-D) fiber alignment modules would offer great benefits for high-density photonic interconnects at the multichip-module level, where parallel light signals have to be transferred between integrated dense 2-D emitter and detector arrays, or for massive parallel sensing applications. In telecom, the availability of highly accurate low-cost field installable 2-D fiber couplers would boost the further integration of fiber optics in future fiber-to-the-home networks. We present deep proton writing as a prototyping technology for the mastering of small-form-factor 2-D fiber connector components. The alignment components, which we present here, consist of 4 times 8 arrays of circular conically shaped holes for single-mode fibers and feature average insertion losses of 0.062 dB and a maximum loss of 0.15 dB, when used in a fiber butt-coupling configuration