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Large-area p-type HIP-MWT silicon solar cells with screen printed contacts exceeding 20% efficiency

physica status solidi (RRL) - Rapid Research Letters (Impact Factor: 2.34). 08/2011; 5:286-8. DOI: 10.1002/pssr.201105311

ABSTRACT The MWT-PERC (metal wrap through passivated emitter and rear cell) concept introduced in 2006 [1, 2] combines the advantages of surface passivation [3] and the metal wrap through approach [4], resulting in an increased conversion efficiency. However, due to the required structuring of the emitter on the rear side, the process sequence is rather complex. Our simplified structure for passivated MWT solar cells, called HIP-MWT (high-performance metal wrap through), maintains the gain in efficiency while reducing the process complexity to a minimum. The simplified structure omits the formation of an emitter region on the rear surface. Therefore no structuring steps are required. Within this work, we present solar cells based on the simplified HIP-MWT structure and non-simplified MWT-PERC reference cells. The cells of both concepts are processed in parallel to enable a direct comparison.

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Available from: Daniel Biro, Jun 29, 2015
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