A technology that uses tiny droplets of metallic ink to draw circuit lines could halve the cost of making circuit boards.
Just about every electronics device in the world uses one or more circuit boards to create a base for different chips and electronics devices to sit on and to link them together. As a result the new inkjet technology, developed by Seiko Epson, could drive down the cost of notebook computers and mobile phones.
The technology draws patterns and connections in layer after layer using an ink that conducts electricity and an ink that acts as an insulator. The process is similar to that used by inkjet printers
Akio Mori, head of Seiko Epson's production engineering and development division, said the droplets of silver conductive ink ranged in size from about 10 nanometers to several tens of nanometers in diameter - on a par with the dimensions of boards made by today's electronics companies.
Seiko Epson has made a 20-layer circuit board 20mm square and 200 microns thick. The circuit lines are 50 microns wide and about four microns high, with 110 microns spacing between the lines. Current circuit boards use roughly the same measurements and spacing, according to the company. As the droplets of ink are so small, Seiko Epson believes it can eventually make lines 15 microns wide.
Multilayer circuit boards are normally produced by coating a board in copper and then using chemicals to etch the lines. The process uses patterning masks and involves drenching the boards in acid.
But Seiko Epson's process doesn't need a patterning mask and avoids the use of a number of industrial chemicals. "This is an extremely simple, maskless technology," said Mori.
As well as silver, lines can be made of aluminium, nickel or magnesium. The insulator ink is made of an organic material that Seiko Epson won't disclose.
The process is similar to the inkjet technology the company developed to make very large organic light-emitting diode (OLED) screens. In May it developed an OLED screen with a 40in diagonal, and hopes to produce TV screens using the technology commercially in 2007.
Seiko Epson hopes to begin commercial production of circuit boards using inkjet technology in 2007.
Paul Kallender writes for IDG News Service