Direct-write techniques for maskless production of microelectronics: a review of current state-of-the-art technologies

Recently, there has been growing interest in direct-write methods for the manufacturing of microelectronic products, as the entire electronics industry sector is aiming towards low cost, rapid manufacturing and shorter time-to-market, as well as reduced environmental impacts. This paper will review the main direct-write techniques, most of which have been invented or seen significant development during the last decade. These techniques include droplet-based direct writing, such as inkjet printing, filament-based direct writing, such as the Micropen and nScrypt processes, tip based directwrite methods, and laser beam direct writing. For each category, only a few examples are presented, although there are a number of specific methods and variants within each of these categories.