TOPCON Is Canceling The Full-scale Introduction of SE in Favor of LECO, Which Can Increase Efficiency by 0.2-0.5%

LECO (Laser-enhanced contact optimization) can improve efficiency by 0.2-0.5% by reducing contact resistance and enhancing cell efficiency.

LECO is an advanced laser sintering technique used to improve the contact between metal electrodes and silicon wafers in solar cells. In LECO processing, lasers are used for non-destructive carrier injection, with the driving force of the process induced by LECO-generated currents. This occurs after the rapid firing process in screen-printed solar cells. Following LECO treatment, the contact resistance of solar cells is significantly reduced, allowing for contact formation even on lightly doped emitters.

In the manufacturing process of photovoltaic cells, especially for TOPCon (Tunnel Oxide Passivated Contact) solar cells, LECO technology can precisely disrupt the passivation layer on the silicon wafer's surface, forming an optimized metal/silicon contact point. For TOPCon cells, the structural design requires finding a balance between surface passivation and metal contact to minimize electron-hole recombination while maintaining good current collection.

LECO technology allows for high-quality metal contact points to be achieved without compromising passivation layer characteristics. It can selectively disrupt the passivation layer in a highly precise manner, facilitating electron transfer between metal and silicon. TOPCon solar cells using LECO technology can enhance their conversion efficiency, typically resulting in efficiency improvements of 0.2% to 0.5%.