Issue link: https://iconnect007.uberflip.com/i/636678
56 The PCB Magazine • February 2016 by Osamu Sekine nAno SYSTEM InC. The trend for laser-drilled microvias keeps moving toward smaller diameters for higher- density PCB design. Along with the smaller mi- crovias, demands for laser-drilling technologies will begin to shift further from CO 2 laser sys- tems to UV laser (3 rd and possibly 4 th harmon- ics UV DPSS lasers) or combination tools such as UV/CO 2 dual laser systems. Our team sees the current needs within the U.S. marketplace heading towards modular platforms allowing for upgrades as technology shifts to reduce capital costs for companies operating within the U.S.; such upgrades include precision op- tics, faster scanning technology, and new laser wavelengths and properties, as well as material handling needs. There are continuous demands of laser- drilled microvias on PCBs from smart electronic devices, or products that fall within the realm of the Internet of Things (IoT). Smart electronic devices require implementing and integrating various types of PCBs such as HDI boards, pack- aging substrate boards and/or flexible circuit boards within limited space in a flexible layout. CO 2 laser systems have been considered the main tools to produce 60–100 mm diameter vias on HDI or packaging substrate boards because of the strong advantages of high throughput and effective cost. Flexible circuit board fabrication has mainly utilized UV laser systems to drill 75– 100 mm diameter microvias; however, flex cir- cuits need fewer laser vias compared with other applications. The development of smaller mi- crovias continues towards <50 mm in diameter, with smaller vias earmarked for next-generation applications within the next two to five years. Smaller via sizes overall may push laser system capital investments from CO 2 laser products to exclusively UV lasers, which normally drill the smaller vias. The problem UV currently faces is the comparison to CO 2 laser systems, which of- fer advantages in terms of throughput and total cost of ownership. UV laser drilling technology has been utiliz- ing trepanning motion, driven by galvanometer scanners or other scanning devices with a tight- ly focused laser spot size, 25 mm or smaller. Due feature