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In this work, we show the integration of polysilicon‐based passivating contacts in plated bifacial n‐type PERT (passivated emitter and rear totally diffused) solar cells. We show the viability of n‐PERT cells using two‐side passivating contacts with two‐side plated nickel/silver metallization. Compared with commercially available "TOPCon" cells with rear side passivated contacts only, n‐PERT cells with both side passivated contacts should enable the exploitation of the full potential of passivated contacts. We show that both n‐poly and p‐poly were applied and co‐plated successfully on both sides of n‐PERT solar cells. Considering the potential parasitic absorption losses on the front side of the device originating from p‐poly, we applied selective p‐poly by patterning. We compared two patterning methods for front side polysilicon: the masking and etch approach using inkjet printing and a simple and cost‐effective patterning method using UV laser oxidation. A best efficiency of 22.7% has been achieved with these cells so far on large area (244.3 cm2) n‐type Cz, with a potential efficiency above 24%. Some of these co‐plated bifacial cells have been processed into one‐cell laminates using smart wire interconnection (SWCT) technology. These have passed thermal cycling (TC) tests as defined in IEC61215. [ABSTRACT FROM AUTHOR]

We report on the progress of imec's n-type passivated emitter, rear totally diffused rear junction silicon solar cells. Selective laser doping has been introduced in the flow, allowing the implementation of a shallow diffused front surface field and a reduction of the recombination current in the contact area. Simplifications have been implemented towards a more industrial annealing sequence, by replacing expensive forming gas annealing steps with a belt furnace annealing. By applying these improvements, together with an advanced texturing process and emitter passivation by atomic layer deposition of Al2O3, 22.5% efficient cells (three busbars) have been realized on commercial 156 · 156 mm2 Czochralski-Si. This result has been independently confirmed by ISE CalLab. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

n-type silicon wafer solar cells are receiving increasing attention for industrial application in recent years, such as the n-type rear-junction Passivated Emitter Rear Totally-diffused (PERT) solar cells. One of the main challenges in fabricating the n-PERT solar cells is the opening of the rear dielectric for localized contacts. In this work laser ablation is applied to locally ablate the rear dielectric. We investigate the laser damage to the emitter at the laser-ablated regions using the emitter saturation current density, Joe,laser, extracted by two approaches. Joe,laser is observed to be injection dependent due to high Jo2 recombination caused by laser damage to the space charge region. By using the optimized laser ablation parameters, n-PERT solar cells with an efficiency of up to 21.0% are realized. [ABSTRACT FROM AUTHOR]