Photothermal characterrization by atomic force microscopy around grain boundary in multicrystalline silicon material

Abstract

Nonradiative recombination of photocarriers around grain boundaries is important property in multicrystalline silicon material, and has been investigated through local photothermal (PT) measurements by atomic force microscopy. We found that the PT signal was apparently enhanced near the grain boundary, which is probably due to fast nonradiative recombination at the boundary. In addition, relationship between the dependence of PT signal on incident photon energy and the minority carrier diffusion length is discussed.