Imec and BESI Successfully Demonstrate Long-Term Reliability of PV Module Based on Ni-Cu-Ag Plated Solar Cells

Recently, at the SiliconPV conference, nano-electronic research center imec and Besi, a leading manufacturer of assembly equipment for the semiconductor industry, announced that they have demonstrated long-term reliability of their 60-cells Ni/Cu/Ag plated solar module, passing 600 thermal cycles, three times the IEC61215 specification, with only minimal power loss of one percent.

The module consists of 60 front side laser ablated and Ni-Cu-Ag plated p-type Cz-Si cells. The plating was done in an industrial Meco vertical plating tool (Direct Plating Line) followed by annealing in an inline belt furnace. Cells were interconnected using a standard solder and lamination process. Thermal cycling tests (-40°C to + 85°C) carried out on the full 60 cell module resulted in an overall power loss of only one percent after 600 hours—three times the standard IEC61215 test protocol. Previous damp heat testing on 30 cells in mini modules successfully passed 1.5X standard IEC61215 specification. These test results prove the long-term reliability potential of imec’s and Besi’s Cu-plated cells and modules, as they have now outperformed the industrial standard for reliability, which requires less than five percent loss relative to initial power after 200 thermal cycles or 1000hrs damp heat testing.

“We are very pleased with this superb result”, says Richard Russell, prinicpal scientist at imec. “It proofs our unique and excellent know how on how to make reliable Ni-Cu-Ag plated solar cells and modules with an industrial manufacturing process.”

“These results confidently prove that modules featuring on-copper plated cells are reliable and outperform IEC61215 life test criteria,” stated Martijn Zwegers, product manager solar at Besi. “This breakthrough gives further momentum to the industry acceptance of Ni-Cu-Ag plating as a low-cost alternative to front side screen printing of Ag pastes.”