The cover shows a tool operator measuring the total thickness variation of an adhesive interlayer of a temporary bonded wafer by taking 280,000 measurement points. For thickness measurements,a high number of measurement points is needed to achieve proper accuracy. Local deviations,such as particles within the bond interface, have a significant effect on the subsequent thinning process, which can lead to wafer breakage and tool downtime.
The cover shows two different optoelectronic interconnection methods developed to enable photon and electron conversion at the level of the microelectronic (logic) chip. Parallelized optical fibers (front) and lithographically-defined compliant polymer waveguides (behind) carry data in optical form to/from the IC. The flip-chip bumps on each die form the electrical connections to the package substrate. As optoelectronic conversion moves closer to the chip, improved data transfer speeds, bandwidth and power efficiencies are expected.