Luo Junxian, Zhou Kanghu, Ma Yingqing, Lei Yu, Liu Hanwen, Tong Hongwei, Xiao Richard, Wang Yuwen, Chen Ye, Chen Zhuo, Xu Fei
Opt Express. 2022 Nov 7;30(23):41092-41100. doi: 10.1364/OE.472518.
Driven by the increasing demand for faster high-performance computing (HPC) networks and higher data center fabric transmission bandwidth, to favorite the needs of machine learning, data training, and computing, the adoption of co-packaged optics (CPO) and near-packaged optics (NPO) is one of the innovations to mitigate the slowing down of Moore's law. Because of the high temperature generated by the next generation of high-speed chips like switch ASICs, CPUs, and GPUs, coupling fibers to photonic integrated circuit (PIC) with traditional epoxy-based fiber arrays is becoming more challenging and problematic. Therefore, an epoxy-free bonding method using femtosecond laser welding borosilicate glass 3.3 and optical fibers is proposed and demonstrated. Then, a low loss and polarization independent fiber to fiber coupling was demonstrated to show the reliability of bonding. In the experiment, a V groove is used for aligning and positioning two fibers. After welding, the minimum coupling loss and polarization dependent loss is 0.347 dB and below 0.1 dB respectively. The average shear force limit of the welded samples with 0.5 mm welding length is measured to be as high as ∼0.719 N. This technology could be used for epoxy-free based edge coupling the high density multi-fibers with PIC and has potential of scalable manufacturability through automation.
受对更快的高性能计算（HPC）网络和更高数据中心架构传输带宽日益增长的需求驱动，为满足机器学习、数据训练和计算的需求，采用共封装光学（CPO）和近封装光学（NPO）是缓解摩尔定律放缓的创新之一。由于诸如交换ASIC、CPU和GPU等下一代高速芯片产生的高温，使用传统基于环氧树脂的光纤阵列将光纤耦合到光子集成电路（PIC）变得越来越具有挑战性和问题。因此，提出并演示了一种使用飞秒激光焊接硼硅酸盐玻璃3.3和光纤的无环氧树脂键合方法。然后，演示了低损耗和偏振无关的光纤到光纤耦合，以展示键合的可靠性。在实验中，使用V形槽对两根光纤进行对准和定位。焊接后，最小耦合损耗和偏振相关损耗分别为0.347 dB和低于0.1 dB。测量了焊接长度为0.5 mm的焊接样品的平均剪切力极限高达约0.719 N。该技术可用于将高密度多光纤与PIC进行无环氧树脂边缘耦合，并具有通过自动化实现可扩展制造性的潜力。
