Solderjet bumping for the assembly of optical fibers

Further miniaturization of 3D-integrated hybrid optical systems on smart system platforms requires a fast and flexible joining technology that overcomes limitations of standard bonding processes in optics. Laser-based solder bumping with its complete integration of solder alloy preform handling, reflowing and application of the solder volume simplifies the joining process and enables for flux-free soldering of micro-optical components with localized and time restricted energy input within a local nitrogen atmosphere. Solder joints provide increased mechanical strength, a higher long term, thermal and radiation stability and good thermal and electrical conductivity compared to polymeric adhesives commonly used for optical bonding. A demonstrator system of a fiber-coupling unit using a polarization maintaining optical fiber (PMF) that is soldered to a V-groove by solderjet bumping with submicron accuracy is described in this work. The development of a device for batch PVD-metallization of the fibers for the creation of necessary wetting surfaces and a miniaturized mechanical gripper enabling for both translational adjustment and the axial alignment of the fiber at the joining geometry is reported.

Further miniaturization of 3D-integrated hybrid optical systems on smart system platforms requires a fast and flexible joining technology that overcomes limitations of standard bonding processes in optics. Laser-based solder bumping with its complete integration of solder alloy preform handling, reflowing and application of the solder volume simplifies the joining process and enables for flux-free soldering of micro-optical components with localized and time restricted energy input within a local nitrogen atmosphere. Solder joints provide increased mechanical strength, a higher long term, thermal and radiation stability and good thermal and electrical conductivity compared to polymeric adhesives commonly used for optical bonding. A demonstrator system of a fiber-coupling unit using a polarization maintaining optical fiber (PMF) that is soldered to a V-groove by solderjet bumping with submicron accuracy is described in this work. The development of a device for batch PVD-metallization of the fibers for the creation of necessary wetting surfaces and a miniaturized mechanical gripper enabling for both translational adjustment and the axial alignment of the fiber at the joining geometry is reported.