Screen-printed silicon solar cell with novel rear-surface
20.1 percent efficiency with a typical industrial process and production sequences.
20.1 percent efficiency with a typical industrial process and production sequences.
The Institute for Solar Energy Research Hameln (ISFH) increases in co-operation with Singulus Technologies AG, the efficiency of screen-printed silicon solar cells of the PV industry today in the usual 17.0 percent to 18.5 percent to a record breaking 20.1 percent. This was confirmed by the Fraunhofer ISE in an independent measurement. An improved cell back with an ICP-AlO x / SiN y bilayer made this progress without the "selective emitter" technology. 20.1 percent is one of the world's highest measured efficiencies for industrial-type solar cells with Siebdruckmetallisierung (only Schott Solar and Q-Cells achieved with 20.2 percent more efficient).
Two technological improvements allow for increased efficiency: First, the back of the solar cells with an ICP-AlO x / SiN y double layer passivated. ICP stands for "Inductively Coupled Plasma" and called for the AlO x novel ISFH Singulus developed in cooperation with deposition method. The contact on the back of the cell is carried out with prepared by laser ablation, line-shaped contact openings. The modified cells back reflects sunlight better and also reduces the charge carrier recombination, thereby improving the current and voltage of the cell. On the other hand, the cell front by double printing (print-on-print), metallized contact fingers which allows smaller and therefore less shading.
In addition, the solar cell made with typical industrial process sequences, in particular with a homogeneous phosphorus-doped emitter as well as with a 156 x 156 square millimeters Czochralski (Cz) silicon wafer. About 80 percent of today's industrially produced solar cells using p-type crystalline 156 x 156 square-millimeter silicon wafers in combination with screen printing for metallization. Increases in efficiency of such cells therefore have a particularly high relevance for the manufacturing industry and are a subject of extensive research worldwide.
ISFH / PH
