Growth and characterization of multi-crystalline silicon ingots


Growth and characterization of multi-crystalline silicon ingots

Schmid, E.; Funke, C.; Behm, T.; Würzner, S.; Pätzold, O.; Galindo, V.; Stelter, M.; Möller, H.-J.

This paper summarizes studies in the field of growth and characterization of multi-crystalline (mc) silicon ingots performed within the Cluster of Excellence "Structure Design of Novel High-Performance Materials via Atomic Design and Defect Engineering (ADDE)". Experimental results on the interaction between impurities, inclusions, dislocations and grain boundaries in multi-crystalline (mc) silicon ingots grown from well-mixed and poorly mixed melts in graphite-containing and graphite free configurations are presented. The ingots were grown in a high-vacuum induction furnace by the vertical Bridgman (VB) method and the degree of impurity mixing within the melt was modified by changing the growth configuration and the growth rate. Vertical and horizontal slices were prepared from the ingots and analyzed by Fourier transform IR spectroscopy, as well as reflected-light and IR transmission microscopy to measure the axial carbon concentration and the distribution of dislocations or inclusions, respectively. The correlation between individual inclusions and dislocations has been investigated by correlative reflected-light/IR transmission and scanning electron microscopy in both setups. The influence of the melt mixing on the segregation of carbon is demonstrated and discussed with respect to the consequences for the formation of inclusions and dislocation clusters in multi-crystalline silicon. Additionally the alignment of dislocations in samples from VB-grown ingots and wafers from edge-defined film-fed (EFG) growth are investigated. Crystallographic orientations of single grains and dislocation structures are analyzed by electron backscatter diffraction and by the "traces on two parallel surfaces" method. The influence of the growth and cooling conditions on the final alignment of dislocations in mc-Si is discussed and explained.

Keywords: multi-crystalline (mc) silicon ingots

  • Contribution to external collection
    Rafaja, David: Functional structure design of new high-performance materials via atomic design and defect engineering (ADDE), Freiberg: Saxonia, 2016, 978-3-934409-68-2, 26-41

Permalink: https://www.hzdr.de/publications/Publ-23471
Publ.-Id: 23471