Cathodoluminescence study of dislocation-related luminescence from small-angle grain boundaries in multicrystalline silicon

Dislocation-related luminescence from small-angle grain boundaries (SA-GBs) in multicrystalline Si was investigated by cathodoluminescence. D3 and D4 emissions were detected at SA-GBs with a misorientation angle of around 1°–1.5°, and D1 and D2 at SA-GBs with a misorientation angle of around 2°–2.5°. Electron beam-induced current investigations indicate that the former SA-GBs possess only shallow energy levels, while the latter possess both deep and shallow levels. The origins of D-line luminescence at SA-GBs are discussed in terms of dislocation structures.