Study of the solidification front of Si films in lamp zone melting controlled by patterning the underlying SiO2

Abstract
A periodic heat‐sink structure has been tested in lamp recrystallization of thin polycrystalline silicon films deposited on oxidized wafers. The defects generally encountered in this type of recrystallization, grain and subgrain boundaries, are localized in specifically designed areas. This localization technique and especially the occurrence of unlocalized defects are interpreted taking into account the breakdown of the solidification front. Beside faceting effects, constitutional supercooling due to impurity segregation is found to play a major role in this type of recrystallization.