Applying of a phase-shifting digital holography combined with compressive sensing to inspect the soldering quality of
surface mount technology (SMT) which is a method for producing electronic circuits. In SMT, the components are
mounted and connected with each other directly onto the surface of printed circuit boards (PCBs). By reconstructing the
multidimensional images from a few samples of SMT, the results are solved by an optimization problem. In this paper,
two problems have been concerned. The first one is to examine the devices and the soldering quality of connections
between them, which are in micro-scaled. The second is to observe the effect of heat treatment of soldering material and
devices on the surface mount board.
In this paper we propose a modern technique to evaluate the shape changes of solder paste by using double-view in-line digital holography. We observed the transformation of three different kinds of solder paste composition: pure solder paste, solder paste mixed with 0.02%, 0.05%, 0.10% graphene (GPN) and 0.02%, 0.05%, 0.10% graphene oxide (GPNO), respectively. The shape of the solder pastes was investigated at different melt temperatures (i.e. 200°C, 250°C, and 300°C) for 30 seconds using a collimated beam propagating through the solder paste, then being double reflected on a mirror and second incident on another sides of the solder paste. The double images bearing beams were recorded with a CCD sensor simultaneously. The single recorded digital hologram from double view technique was reconstructed using digital holography. The results show that the double-view technique provides reliably data. Moreover, it would be developed for observing more than two images by single holography writing in the future.