Silver Nano 2.0

Cima NanoTech made the first public announcement this week of what I like to think of as “silver nano 2.0.” By that I mean that Cima’s product is a “second generation” of silver-based transparent conductor, potentially surpassing Cambrios Technologies’ original (1.0) silver nanowires that were first shipped in 2011. Except that it’s not nanowires; it’s a self-assembling silver mesh made from a liquid containing silver nanoparticles.

Cima’s product, named SANTE, is an entirely new form of transparent-conductor film aimed at replacing ITO in p-cap touchscreens. (SID named it one of four Best in Show winners on Wednesday, May 22.) It starts with an opaque liquid that’s coated on PET, PC, glass, or any other substrate using industry-standard roll-to-roll film-coating equipment. Within 30 seconds, the liquid dries into a mesh consisting of 200-300 micron open spaces with 3-to-5 micron connecting conductors (see the figures below). The transparency and sheet resistivity of the film are fairly competitive with those of (typically) copper-based metal mesh, which means the film offers better performance in both areas than silver nanowires. Since the mesh openings are randomly shaped, there is no relationship between the LCD pixel structure and the silver mesh pattern. This means that unlike with metal mesh, there is no possibility of moiré patterns and the sensor layout can be designed (or modified) by the touchscreen module-supplier rather than the touchscreen controller-supplier. The mesh can be patterned into drive and sense electrodes using conventional wet (chemical) or dry (laser) etching.

In addition to the touchscreen market, Cima is also planning to use different formulations of the product to address the EMI shielding, transparent heater, photovoltaic, OLED lighting, and flexible-electronics markets. First shipments of the touchscreen film are planned for 3Q-2013. – Geoff Walker