Michael D. Wheeler, News Editor
In the fledgling days of the semiconductor industry, chip makers encoded serial numbers and dates on integrated circuit packages using conventional pad printed or ink-jet techniques. These methods offered users a high-contrast mark at a relatively affordable cost, but they also resulted in fumes, occasional smudging and the tedious task of refilling vast ink reservoirs.
As incidents of counterfeit chips surfaced, so did concerns over ink's permanence. This spurred the industry to look for alternatives, and by the early 1980s the photonics sector took its cue and rolled out the first laser marking systems.
Much has changed over the last tow decades. Now chip makers can choose sealed or transversely excited atmospheric pressure CO2 system. Solid-state technology arrived about 15 years ago -- first the flashlamp-pumped Nd:YAGs and, recently, the diode-pumped version. These new systems offer excellent beam quality and low maintenance, but both carry heftier price tags.