FIB-SEM based 3D tomography of micro-electronic components: Application to automotive high-definition LED lighting systems

In new high definition lighting modules, assembling more than thousand elements (pixels) with a single mm-sized motherboard is achieved by reflow soldering. Lead-free solders may constitute weak part of electronic components and LED assemblies. During reflow, the distance between pixels controls solder heights (10 μm). After assembly, all are in plane. To ensure constant heights, this plane has to be parallel motherboard. A small disorientation during lead severe damage prior any use opto-electronic component. Present work presents novel non-destructive method for characterizing chosen assembled component without unpacking latter. femtosecond motorized laser source used digging hole above selected solder. Then Focused Ion Beam facility allows mill around specific The same FIB making several hundred slices controlled thickness orientation material. slicing operation, high-resolution inspection done FEG-SEM (Field Emission Gun - Scanning Electron Microscope) imaging. 3D tomographic reconstruction obtained classical commercial software AVIZO. Finally, material illustrated example results.