Trident Solar (www.tridentsolarcell.com ), a division of Trident ITW, and Alpha (www.alpha.cooksonelectronics.com ), a Cookson Electronics company, have announced a new collaboration bringing innovative, additive, non-contact inkjet deposition technologies to the solar market.
Trident Solar and Alpha have worked together to bring a complete solution to photovoltaic cell manufacturers for direct pattern printing and etching using Trident's inert 256Jet-S™ inkjet printhead and Alpha's line of jettable solar materials including both p and n dopants, dielectric, silver conductive metallic inks and etchants. Together, these additive, non-contact inkjet technologies provide enhanced production yields and have the potential to increase cell efficiency up to 1% when compared to the use of traditional screen printing technologies.
"With a truly global presence and well-known reputation as a world class supplier to the electronics industry, Cookson Electronics/Alpha was the ideal company for Trident to collaborate with in order to bring the performance and production benefits of the additive, non-contact inkjet process to the photovoltaic market," explained Steve Liker, Business Manager at Trident Solar. "Alpha has created high performance jettable photovoltaic materials that provide unprecedented performance in the photovoltaic market."
"Alpha is proud of the collaboration with Trident Solar as their inkjet technology stands out for solar applications," said Mike Marczi, Director of Business Development at Alpha. "Whereas other inkjet companies simply adapt existing printheads for the photovoltaic market, Trident Solar has developed repairable, inert, stainless steel printhead technology that is specifically designed to provide reliable performance with the aggressive materials used in solar technologies. Trident printheads have 10x the life expectancy of other inkjet printheads when printing acid and alkaline solutions for solar applications and are well suited for jetting Alpha's etchant inks."
Inkjet deposition allows for etching of very narrow feature line widths with SiNx, a-Si or c-Si. The new technology has demonstrated an etched feature line width of 100 microns with technology development roadmap to enable production of etched features as narrow as 40 microns.
Cell efficiency is further enhanced through inkjet's capability to etch away SiNx reflective material on photovoltaic cells in the valleys and peaks of the silicon active layer, ensuring minimal resistivity of the contact to the silicon.
Inkjet can also be used to jet conductive metal inks (such as silver ink) to digitally produce contact lines with thickness, 2x-3x finer than can be produced with silver paste and rotary screen printing. The reduced contact line width reduces shadowing on the active layer enabling increased cell efficiency.
This high-resolution, direct-write printing method offered by the new Trident/Alpha partnership also saves in process steps, speeds set-up time, eliminates waste, reduces cost through automation, and enables non-contact printing for thin, sensitive substrates. Lines or holes can be produced without the damage and defects associated with lasers. Digital printing is non-contact so breakage and resulting scrap are eliminated. The additive inkjet process allows manufacturers to print exactly the amount of material they need exactly where they need it, saving significant time, expense, and waste.
The collaboration between Trident Solar and Alpha was formally announced at the 25th Annual European Photovoltaic Solar Energy Conference (September 6-10, 2010 - Valencia, Spain) where Trident showcased inkjet technologies for solar applications at booth H4/L3/B7 and Alpha highlighted their jettable photovoltaic materials at booth H2/L2/C7.
For more read : Energy Harvesting and Storage for Electronic Devices 2010-2020