Variation of dislocation etch-pit geometry: An indicator of bulk microstructure and recombination activity in multicrystalline siliconShow others and affiliations
2014 (English)In: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 115, no 18, p. 1-7, article id 183511Article in journal (Refereed) Published
Abstract [en]
Dislocation clusters in multicrystalline silicon limit solar cell performance by decreasing minoritycarrier diffusion length. Studies have shown that the recombination strength of dislocation clusterscan vary by up to two orders of magnitude, even within the same wafer. In this contribution, wecombine a surface-analysis approach with bulk characterization techniques to explore theunderlying root cause of variations in recombination strength among different clusters. We observethat dislocation clusters with higher recombination strength consist of dislocations with a largervariation of line vector, correlated with a higher degree of variation in dislocation etch-pit shapes(ellipticities). Conversely, dislocation clusters exhibiting the lowest recombination strength containmostly dislocations with identical line vectors, resulting in very similar etch-pit shapes. Thedisorder of dislocation line vector in high-recombination clusters appears to be correlated withimpurity decoration, possibly the cause of the enhanced recombination activity. Based on ourobservations, we conclude that the relative recombination activity of different dislocation clustersin the device may be predicted via an optical inspection of the distribution and shape variation ofdislocation etch pits in the as-grown wafer.
Place, publisher, year, edition, pages
American Institute of Physics (AIP), 2014. Vol. 115, no 18, p. 1-7, article id 183511
Keywords [en]
etching, dislocations, solar cell, TEM, µ-XRF, silicon, copper
National Category
Electrical Engineering, Electronic Engineering, Information Engineering Materials Engineering Condensed Matter Physics
Research subject
Physics
Identifiers
URN: urn:nbn:se:kau:diva-33996DOI: 10.1063/1.4876445ISI: 000336919400015Scopus ID: 2-s2.0-84901483994OAI: oai:DiVA.org:kau-33996DiVA, id: diva2:752464
2014-10-032014-10-032019-08-14Bibliographically approved