Presentation Details
| Femtosecond UV-Laser Contact Opening for LECO Metallization in TOPCon Solar Cells Thien Truong, William Nemeth, Steve Johnston, Jacob Slifka, David Young, Paul Stradins. National Laboratory of the Rockies, Golden, CO, USA |
Abstract
Laser-enhanced contact optimization (LECO) is a key technology for the fabrication of high-efficiency silicon (Si) solar cells. In this work, we demonstrate, for the first time, the use of a femtosecond ultraviolet laser to facilitate contact opening between the Ag metal paste and the Si substrate. This approach allows precise control of contact resistivity and passivation through laser parameters, rather than relying on a compromise between LECO settings and firing conditions. We show that ~1 µm laser-opened pinholes patterned with 20 µm spacing beneath the finger grid effectively improve the J–V characteristics of finished devices, even without LECO treatment. Subsequent LECO processing may further enhance cell performance, requiring significantly lower laser power and applied voltages compared to conventional cells without laser-assisted contact pre-opening. This work provides a promising pathway to improve metallization in TOPCon cells, with potential for reduced LECO-associated processing costs.
No part of this publication may be reproduced, distributed, or transmitted in any form or by any means, including photocopying, recording, or other electronic or mechanical methods, without the prior written permission of the author.
No part of this publication may be reproduced, distributed, or transmitted in any form or by any means, including photocopying, recording, or other electronic or mechanical methods, without the prior written permission of the author.