IR characterization of hydrogen in crystalline silicon solar cells

Abstract Hydrogen is commonly introduced into silicon solar cells to reduce the deleterious effects of defects and to increase cell efficiency. A process that is widely used by industry to introduce hydrogen is by the post-deposition annealing of a hydrogen-rich SiN x layer that is used as an anti-reflection coating. A number of questions about this hydrogen introduction process and hydrogen's subsequent interactions with defects have proved difficult to address because of the low concentration of hydrogen that is introduced into the Si bulk. We have used the fundamental knowledge of hydrogenated defects that has been revealed by recent investigations of impurity–H complexes to develop strategies by which hydrogen in silicon can be detected by IR spectroscopy with high sensitivity. The introduction of hydrogen into Si by the post-deposition annealing of a SiN x coating has been investigated.