The relentless demand for smaller and lighter products with faster and more powerful processing capabilities continues to be the overarching trend across nearly every sector of the electronics market: from telecom systems to medical sensors, image processing, and of course smart phones and devices. Today, advanced package integration (API) is arguably the key technological enabler supporting this trend, with a focus on vertical stacking platform – so-called 2.5D and 3D architectures – or fan-out wafer level packaging (FOWLP) as preferred in high bandwidth memory (HBM). An example of a true 3D package is where two (or more) thinned chips are stacked on top of each other in the same molded package, such as several memory chips or the combination of a logic chip and a memory chip. Excimer laser structuring offers multiple advantages in advanced packaging applications including ablation of vias and trenches, seed layer removal, and debonding. This technology is proven to provide a cost advantage for both current and future packaging applications. Whereas lithographic patterning involves photographic exposure of a resist, the excimer laser pulses directly remove material with virtually no peripheral thermal effects. A proven means to increase achievable field size is overlaying time-synchronized combined beams. Therefore, a sensitivity analysis of applying 308-nm excimer laser double pulses using various pulse delays on the key ablation parameters has been conducted.
|