Double Printing nPERT Cells with Narrow Contact Layers

Abstract Screen printing of two different paste layers on top of each other is used for reducing the detrimental effect of the p+ contact to nPERT cells. For the contacting layer, a line width between 15 μm and 30 μm is used. In a second print step, using a wider opening, these contacting layers are augmented by a non-contacting paste layer to form a line of sufficient conductivity. Reduced shading and a smaller contact area lead to increased JSC and VOC. Still, an excessive reduction of the contact area causes an increase of contact resistivity compensating the gain. For an optimum configuration, an efficiency gain of up to 0.2%abs and a reduction of paste consumption by 10 mg are demonstrated on precursors from industrial production.