The impacts of grain boundary character and impurity contamination level on the H passivation of grain boundaries in multi-crystalline Si were studied by means of an electron-beam-induced current technique. In mc-Si with a low contamination of Fe, the 300K electron-beam-induced current contrast of all kinds of grain boundaries in the H-passivated state was weak and similar to that in the as-grown state. The 100K electron-beam-induced current contrast of Σ (= 3, 9 or 27) grain boundaries decreased by 75 to 80%, whereas that of random and small-angle grain boundaries decreased about 35–40%. Due to the different impurity gettering ability of different grain boundaries, the variation in 100K electron-beam-induced current contrast had suggested that the effect of H-passivation depended upon both the grain boundary character and impurity contamination level. In multi-crystalline Si with heavy contamination of Fe, at both 300 and 100K, the electron-beam-induced current contrast of both Σ (= 3) and random grain boundaries decreased but the ratio was <40%, suggesting that the H-passivation was mainly affected by the impurity contamination level.

Electron-Beam-Induced Current Study of Hydrogen Passivation on Grain Boundaries in Multicrystalline Silicon - Influence of GB Character and Impurity Contamination. J.Chen, D.Yang, Z.Xi, T.Sekiguchi: Physica B, 2005, 364[1-4], 162-9